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1
Edgington-Mitchell, Laura E. "Pathophysiological roles of proteases in gastrointestinal disease". American Journal of Physiology-Gastrointestinal and Liver Physiology 310, n. 4 (15 febbraio 2016): G234—G239. http://dx.doi.org/10.1152/ajpgi.00393.2015.
Abstract (sommario):
Gastrointestinal diseases, such as irritable bowel syndrome, inflammatory bowel disease, and colorectal cancer, affect a large proportion of the population and are associated with many unpleasant symptoms. Although the causes of these diseases remain largely unknown, there is increasing evidence to suggest that dysregulated protease activity may be a contributing factor. Proteases are enzymes that cleave other proteins, and their activity is normally very tightly regulated. During disease, however, the balance between proteases and their inhibitors is often shifted, leading to altered spatial and temporal control of substrate cleavage. Evaluating protease levels in normal physiology and disease has relied heavily on the use of chemical tools. Although these tools have greatly advanced the field, they are not without caveats. This review provides an introduction to these tools, their application in the gut, and a summary of the current knowledge on the contribution of protease activity to gastrointestinal disease.
2
Kryukov, V. S., S. V. Zinoviev e R. V. Nekrasov. "Proteases in the diet of monogastric animals". Agrarian science 344, n. 1 (13 marzo 2021): 30–38. http://dx.doi.org/10.32634/0869-8155-2021-344-1-30-38.
Abstract (sommario):
There are many proteases, and about 2% of the human genome is involved in the regulation of their formation. The share of proteases involved in digestion accounts for only a small part. Despite this, the mechanisms of action of digestive proteases are less studied than carbohydrases and lipases. The incorporation of exogenous proteases into young animal feeds is often accompanied by improved utilization of protein and other nutrients. Exogenous proteases degrade inhibitors of the endogenous protease and lectins in feed. Alkaline proteases are of interest due to their broader substrate specificity and activity throughout the entire gastrointestinal tract. This group includes keratinases, which digest proteins inaccessible for cleavage by proteases and peptidases of animals. Keratinases digest agglutinins, glycinin and b-conglycinin and connective tissue proteins, which are resistant to the action of gastrointestinal enzymes and a number of exogenous proteases. The alleged reasons for the inconsistent results when using feed proteases are described. Their mediated positive effects not associated with proteolysis are indicated. It is advisable to use proteases with keratinolytic activity as fodder proteases.
3
Jones, Jennifer C., Shelly Rustagi e Peter J. Dempsey. "ADAM Proteases and Gastrointestinal Function". Annual Review of Physiology 78, n. 1 (10 febbraio 2016): 243–76. http://dx.doi.org/10.1146/annurev-physiol-021014-071720.
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Herszényi, László, Mario Plebani, Paolo Carraro, Massimo De Paoli, Giovanni Roveroni, Romilda Cardin, Francesca Foschia, Zsolt Tulassay, Remo Naccarato e Fabio Farinati. "Proteases in gastrointestinal neoplastic diseases". Clinica Chimica Acta 291, n. 2 (febbraio 2000): 171–87. http://dx.doi.org/10.1016/s0009-8981(99)00227-2.
5
González-Páez, Gonzalo E., Emily J. Roncase e Dennis W. Wolan. "X-ray structure of an inactive zymogen clostripain-like protease from Parabacteroides distasonis". Acta Crystallographica Section D Structural Biology 75, n. 3 (28 febbraio 2019): 325–32. http://dx.doi.org/10.1107/s2059798319000809.
Abstract (sommario):
The clostripain-like (C11) family of cysteine proteases are ubiquitously produced by the vast majority of the bacterial strains that make up the human distal gut microbiome. Recent reports show that some C11 proteases promote host immune responses and bacterial pathogenesis, including the induction of neutrophil phagocytosis and the activation of bacterial pathogenic toxins, respectively. The crystal structure of distapain, the only C11 protease predicted within the genome of the commensal bacterium Parabacteroides distasonis, was determined in the inactive zymogen state to 1.65 Å resolution. This is the first C11 protease structure of a zymogen, and the structure helped to uncover key unique conformations among critical active-site residues that are likely to assist in preserving the inactive protease. His135, a member of the catalytic dyad, is repositioned approximately 5.5 Å from the orientation found in active C11 structures and forms a hydrogen bond to Asp180 and a π-stacking interaction with Trp133. The structure sheds light on the potential importance of Asp180 and Trp133, as these residues are highly conserved across C11 proteases. Structure elucidation of C11 proteases will ultimately help to identify new ways to chemically and/or biologically regulate this family of enzymes, which represent potential drug-discovery targets in microbiome-related gastrointestinal diseases.
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Lebuan, Urbanus Yustus, Roga Florida Kembaren, Merry Meryam Martgrita e Cut Rizlani Kholibrina. "Thrombolytic protease characterization from leaves and fruit flesh of the jernang rattan plant (Daemonorops draco)". Indonesian Journal of Biotechnology 28, n. 4 (30 dicembre 2023): 248. http://dx.doi.org/10.22146/ijbiotech.82390.
Abstract (sommario):
Thrombolytic agents are used for thrombolytic therapy to dissolve blood clots that form in a blood vessel. All currently used thrombolytic agents have unfavorable shortcomings, such as gastrointestinal bleeding, allergic reactions, and thrombolytic agent resistance, treatment for some of which can be quite expensive. As a result, the search for thrombolytic agents derived from plants is currently taking place. Some plants have been discovered to contain protease enzymes with thrombolytic activity; pharmaceuticals derived from plants are believed to be safer. Jernang rattan (Daemonorops draco) is a plant of the Arecaceae family and is known to produce resin. Jernang rattan resin is also known to have antioxidant, antiseptic, antitumor, antimicrobial, and cytotoxic activity, but very limited information on proteolytic activity of the protease from this plant. This research aims to isolate proteases from the leaves and fruit flesh of the rattan jernang plant (D. draco) and to investigate the proteolytic activity of the isolated proteases. The protease was isolated from the leaves and the fruit flesh, and then partially purified by ammonium sulfate precipitation. The radial caseinolytic assay showed that protease in a 60% ammonium sulfate fraction gave a clear zone, with diameters of 1.4 cm and 1.8 cm for the protease isolated from leaves and fruit flesh, respectively. A Folin‐Ciocalteau assay showed that the enzymes isolated were able to hydrolyze casein and release L‐tyrosine, with activity of 0.158 U/mL and 0.174 U/mL for the protease from the leaves and fruit flesh, respectively. A fibrinogenolytic assay showed that the protease from the fruit flesh hydrolyzed the A‐α, B‐β and the γ chain of human fibrinogen, while the protease from the leaves hydrolyzed the A‐α and γ chain. Both proteases were inhibited by 56% by phenylmethylsulfonyl fluoride (PMSF), indicating that the enzymes are serine proteases. Based on the assay results obtained, it can be concluded that proteases isolated from the leaves and fruit flesh have potential as thrombolytic proteases.
7
Linz, Bodo, Irshad Sharafutdinov, Nicole Tegtmeyer e Steffen Backert. "Evolution and Role of Proteases in Campylobacter jejuni Lifestyle and Pathogenesis". Biomolecules 13, n. 2 (8 febbraio 2023): 323. http://dx.doi.org/10.3390/biom13020323.
Abstract (sommario):
Infection with the main human food-borne pathogen Campylobacter jejuni causes campylobacteriosis that accounts for a substantial percentage of gastrointestinal infections. The disease usually manifests as diarrhea that lasts for up to two weeks. C. jejuni possesses an array of peptidases and proteases that are critical for its lifestyle and pathogenesis. These include serine proteases Cj1365c, Cj0511 and HtrA; AAA+ group proteases ClpP, Lon and FtsH; and zinc-dependent protease PqqE, proline aminopeptidase PepP, oligopeptidase PepF and peptidase C26. Here, we review the numerous critical roles of these peptide bond-dissolving enzymes in cellular processes of C. jejuni that include protein quality control; protein transport across the inner and outer membranes into the periplasm, cell surface or extracellular space; acquisition of amino acids and biofilm formation and dispersal. In addition, we highlight their role as virulence factors that inflict intestinal tissue damage by promoting cell invasion and mediating cleavage of crucial host cell factors such as epithelial cell junction proteins. Furthermore, we reconstruct the evolution of these proteases in 34 species of the Campylobacter genus. Finally, we discuss to what extent C. jejuni proteases have initiated the search for inhibitor compounds as prospective novel anti-bacterial therapies.
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Weiss, Stefanie A. I., Salome R. T. Rehm, Natascha C. Perera, Martin L. Biniossek, Oliver Schilling e Dieter E. Jenne. "Origin and Expansion of the Serine Protease Repertoire in the Myelomonocyte Lineage". International Journal of Molecular Sciences 22, n. 4 (7 febbraio 2021): 1658. http://dx.doi.org/10.3390/ijms22041658.
Abstract (sommario):
The deepest evolutionary branches of the trypsin/chymotrypsin family of serine proteases are represented by the digestive enzymes of the gastrointestinal tract and the multi-domain proteases of the blood coagulation and complement system. Similar to the very old digestive system, highly diverse cleavage specificities emerged in various cell lineages of the immune defense system during vertebrate evolution. The four neutrophil serine proteases (NSPs) expressed in the myelomonocyte lineage, neutrophil elastase, proteinase 3, cathepsin G, and neutrophil serine protease 4, collectively display a broad repertoire of (S1) specificities. The origin of NSPs can be traced back to a circulating liver-derived trypsin-like protease, the complement factor D ancestor, whose activity is tightly controlled by substrate-induced activation and TNFα-induced locally upregulated protein secretion. However, the present-day descendants are produced and converted to mature enzymes in precursor cells of the bone marrow and are safely sequestered in granules of circulating neutrophils. The potential site and duration of action of these cell-associated serine proteases are tightly controlled by the recruitment and activation of neutrophils, by stimulus-dependent regulated secretion of the granules, and by various soluble inhibitors in plasma, interstitial fluids, and in the inflammatory exudate. An extraordinary dynamic range and acceleration of immediate defense responses have been achieved by exploiting the high structural plasticity of the trypsin fold.
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Durán-Pérez, Sergio A., José G. Rendón-Maldonado, Lucio de Jesús Hernandez-Diaz, Annete I. Apodaca-Medina, Maribel Jiménez-Edeza e Julio Montes-Avila. "In Silico Identification and Molecular Characterization of Extracellular Cathepsin L Proteases from Giardia duodenalis". Current Proteomics 17, n. 4 (29 giugno 2020): 342–51. http://dx.doi.org/10.2174/1570164617666191016170628.
Abstract (sommario):
Background: The protozoan Giardia duodenalis, which causes giardiasis, is an intestinal parasite that commonly affects humans, mainly pre-school children. Although there are asymptomatic cases, the main clinical features are chronic and acute diarrhea, nausea, abdominal pain, and malabsorption syndrome. Little is currently known about the virulence of the parasite, but some cases of chronic gastrointestinal alterations post-infection have been reported even when the infection was asymptomatic, suggesting that the cathepsin L proteases of the parasite may be involved in the damage at the level of the gastrointestinal mucosa. Objective: The aim of this study was the in silico identification and characterization of extracellular cathepsin L proteases in the proteome of G. duodenalis. Methods: The NP_001903 sequence of cathepsin L protease from Homo sapienswas searched against the Giardia duodenalisproteome. The subcellular localization of Giardia duodenaliscathepsin L proteases was performed in the DeepLoc-1.0 server. The construction of a phylogenetic tree of the extracellular proteins was carried out using the Molecular Evolutionary Genetics Analysis software (MEGA X). The Robetta server was used for the construction of the three-dimensional models. The search for possible inhibitors of the extracellular cathepsin L proteases of Giardia duodenaliswas performed by entering the three-dimensional structures in the FINDSITEcomb drug discovery tool. Results: Based on the amino acid sequence of cathepsin L from Homo sapiens, 8 protein sequences were identified that have in their modular structure the Pept_C1A domain characteristic of cathepsins and two of these proteins (XP_001704423 and XP_001704424) are located extracellularly. Threedimensional models were designed for both extracellular proteins and several inhibitory ligands with a score greater than 0.9 were identified. In vitrostudies are required to corroborate if these two extracellular proteins play a role in the virulence of Giardia duodenalisand to discover ligands that may be useful as therapeutic targets that interfere in the mechanism of pathogenesis generated by the parasite. Conclusion: In silicoanalysis identified two proteins in the Giardia duodenalisprotein repertoire whose characteristics allowed them to be classified as cathepsin L proteases, which may be secreted into the extracellular medium to act as virulence factors. Three-dimensional models of both proteins allowed the identification of inhibitory ligands with a high score. The results suggest that administration of those compounds might be used to block the endopeptidase activity of the extracellular cathepsin L proteases, interfering with the mechanisms of pathogenesis of the protozoan parasite Giardia duodenalis.
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Upadhyay, Ratna, Mihir Gadan, Supriya Raut e Sneha Badak. "Evaluation of Proprietary MDZenPro Formulation by Zenherb Labs in Mediating Protein Digestion under INFOGEST in-vitro Simulated Gastrointestinal Conditions". International Journal For Multidisciplinary Research 04, n. 04 (2022): 129–38. http://dx.doi.org/10.36948/ijfmr.2022.v04i04.012.
Abstract (sommario):
Protein breakdown by endogenous enzymes in the gastrointestinal (GI) tract results in generation of peptides and amino acids that act as building blocks in essential biological functions. Exogenous proteases possess immense potential as digestive enzyme supplements that can assist protein digestion in the GI system. Plant proteases, in addition to their promising activity, are considered to be safe in nature. The present study evaluated the potential application of a plant protease based proprietary formulation - MDZenPro in digesting raw whey protein, whey protein isolate and plant protein under INFOGEST simulated GI conditions. The gastric and GI digested protein products were analyzed for determining the degree of hydrolysis. The protein profiles were evaluated using SDS-PAGE. The results of the degree of hydrolysis study revealed that MDZenPro facilitated gastric and GI digestion of proteins. This increase in degree of hydrolysis was noted to be higher than that observed in proteins that were not treated with MDZenPro. The SDS-PAGE profile further supported these findings wherein, the MDZenPro treated protein samples displayed low molecular weight fragmented peptides in contrast to the profile of undigested proteins. The present study thus highlights the promising application of ‘MDZenPro’ as an effective supplement for protein digestion.
11
Kirkland, Jacob G., Graeme S. Cottrell, Nigel W. Bunnett e Carlos U. Corvera. "Agonists of protease-activated receptors 1 and 2 stimulate electrolyte secretion from mouse gallbladder". American Journal of Physiology-Gastrointestinal and Liver Physiology 293, n. 1 (luglio 2007): G335—G346. http://dx.doi.org/10.1152/ajpgi.00425.2006.
Abstract (sommario):
Cholecystitis is one of the most common gastrointestinal diseases. Inflammation induces the activation of proteases that can signal to cells by cleaving protease-activated receptors (PARs) to induce hemostasis, inflammation, pain, and repair. However, the distribution of PARs in the gallbladder is unknown, and their effects on gallbladder function have not been fully investigated. We localized immunoreactive PAR1 and PAR2 to the epithelium, muscle, and serosa of mouse gallbladder. mRNA transcripts corresponding to PAR1 and PAR2, but not PAR4, were detected by RT-PCR and sequencing. Addition of thrombin and a PAR1-selective activating peptide (TFLLRN-NH2) to the serosal surface of mouse gallbladder mounted in an Ussing chamber stimulated an increase in short-circuit current in wild-type but not PAR1 knockout mice. Similarly, serosally applied trypsin and PAR2 activating peptide (SLIGRL-NH2) increased short-circuit current in wild-type but not PAR2 knockout mice. Proteases and activating peptides strongly inhibited electrogenic responses to subsequent stimulation with the same agonist, indicating homologous desensitization. Removal of HCO3− ions from the serosal buffer reduced responses to thrombin and trypsin by >80%. Agonists of PAR1 and PAR2 increase intracellular Ca2+ concentration in isolated and cultured gallbladder epithelial cells. The COX-2 inhibitor meloxicam and an inhibitor of CFTR prevented the stimulatory effect of PAR1 but not PAR2. Thus PAR1 and PAR2 are expressed in the epithelium of the mouse gallbladder, and serosally applied proteases cause a HCO3− secretion. The effects of PAR1 but not PAR2 depend on generation of prostaglandins and activation of CFTR. These mechanisms may markedly influence fluid and electrolyte secretion of the inflamed gallbladder when multiple proteases are generated.
12
Keppler, Daniel, Mansoureh Sameni, Kamiar Moin, Bonnie F. Sloane, Tom Mikkelsen e Clement A. Diglio. "Tumor progression and angiogenesis: cathepsin B &Co." Biochemistry and Cell Biology 74, n. 6 (1 dicembre 1996): 799–810. http://dx.doi.org/10.1139/o96-086.
Abstract (sommario):
Experimental and clinical evidence reveals that the growth of solid tumors is dependent on angiogenesis. Proteolytic enzymes such as plasminogen activators and matrix metalloproteinases have been implicated in this neovascularization. The role of lysosomal proteases in this process has yet to be explored. Increased expression of the lysosomal cysteine protease cathepsin B has been observed in many etiologically different tumors, including human brain, prostate, breast, and gastrointestinal cancers. Immunohistochemical and in situ histochemical studies have demonstrated expression of cathepsin B in neovessels induced during malignant progression of human glioblastoma and prostate carcinomas. In these two tumor types, neovessels stain strongly for cathepsin B compared with the normal microvasculature. As an initial point to elucidate whether cathepsin B is an important component of the angiogenic response in tumours, we analyzed expression of cathepsin B in endothelial cells during neovessel formation. We present evidence for strong immunostaining of cathepsin B in rat brain microvascular endothelial cells as they form capillary tubes in vitro. This finding is discussed within the general framework of the role of proteolytic enzymes in tumor invasion and angiogenesis.Key words: proteases, lysosomes, microvasculature, neovessels, tumor invasion.
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Cotton, James A., Amol Bhargava, Jose G. Ferraz, Robin M. Yates, Paul L. Beck e Andre G. Buret. "Giardia duodenalis Cathepsin B Proteases Degrade Intestinal Epithelial Interleukin-8 and Attenuate Interleukin-8-Induced Neutrophil Chemotaxis". Infection and Immunity 82, n. 7 (14 aprile 2014): 2772–87. http://dx.doi.org/10.1128/iai.01771-14.
Abstract (sommario):
ABSTRACTGiardia duodenalis(syn.G. intestinalis,G. lamblia) infections are a leading cause of waterborne diarrheal disease that can also result in the development of postinfectious functional gastrointestinal disorders via mechanisms that remain unclear. Parasite numbers exceed 106trophozoites per centimeter of gut at the height of an infection. Yet the intestinal mucosa ofG. duodenalis-infected individuals is devoid of signs of overt inflammation.G. duodenalisinfections can also occur concurrently with infections with other proinflammatory gastrointestinal pathogens. Little is known of whether and how this parasite can attenuate host inflammatory responses induced by other proinflammatory stimuli, such as a gastrointestinal pathogen. Identifying hitherto-unrecognized parasitic immunomodulatory pathways, the present studies demonstrated thatG. duodenalistrophozoites attenuate secretion of the potent neutrophil chemoattractant interleukin-8 (CXCL8); these effects were observed in human small intestinal mucosal tissues and from intestinal epithelial monolayers, activated through administration of proinflammatory interleukin-1β orSalmonella entericaserovar Typhimurium. This attenuation is caused by the secretion ofG. duodenaliscathepsin B cysteine proteases that degrade CXCL8 posttranscriptionally. Furthermore, the degradation of CXCL8 viaG. duodenaliscathepsin B cysteine proteases attenuates CXCL8-induced chemotaxis of human neutrophils. Taken together, these data demonstrate for the first time thatG. duodenalistrophozoite cathepsins are capable of attenuating a component of their host's proinflammatory response induced by a separate proinflammatory stimulus.
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Clemente, Alfonso, M. Carmen Marín-Manzano, Elisabeth Jiménez, M. Carmen Arques e Claire Domoney. "The anti-proliferative effect of TI1B, a major Bowman–Birk isoinhibitor from pea (Pisum sativum L.), on HT29 colon cancer cells is mediated through protease inhibition". British Journal of Nutrition 108, S1 (23 agosto 2012): S135—S144. http://dx.doi.org/10.1017/s000711451200075x.
Abstract (sommario):
Bowman–Birk inhibitors (BBI) from legumes, such as soyabean, pea, lentil and chickpea, are naturally occurring plant protease inhibitors which have potential health-promoting properties within the mammalian gastrointestinal tract. BBI can survive both acidic conditions and the action of proteolytic enzymes within the stomach and small intestine, permitting significant amounts to reach the large intestine in active form to exert their reported anti-carcinogenic and anti-inflammatory properties. In a previous study, we reported the ability of a recombinant form of TI1B (rTI1B), representing a major BBI isoinhibitor from pea, to influence negatively the growth of human colorectal adenocarcinoma HT29 cells in vitro. In the present study, we investigate if this effect is related directly to the intrinsic ability of BBI to inhibit serine proteases. rTI1B and a novel engineered mutant, having amino acid substitutions at the P1 positions in the two inhibitory domains, were expressed in the yeast Pichia pastoris. The rTI1B proved to be active against trypsin and chymotrypsin, showing Ki values at nanomolar concentrations, whereas the related mutant protein was inactive against both serine proteases. The proliferation of HT29 colon cancer cells was significantly affected by rTI1B in a dose-dependent manner (IC50 = 31 (sd 7) μm), whereas the inactive mutant did not show any significant effect on colon cancer cell growth. In addition, neither recombinant protein affected the growth of non-malignant colonic fibroblast CCD-18Co cells. These findings suggest that serine proteases should be considered as important targets in investigating the potential chemopreventive role of BBI during the early stages of colorectal carcinogenesis.
15
Schumacher, Neele, Stefan Rose-John e Dirk Schmidt-Arras. "ADAM-Mediated Signalling Pathways in Gastrointestinal Cancer Formation". International Journal of Molecular Sciences 21, n. 14 (20 luglio 2020): 5133. http://dx.doi.org/10.3390/ijms21145133.
Abstract (sommario):
Tumour growth is not solely driven by tumour cell-intrinsic mechanisms, but also depends on paracrine signals provided by the tumour micro-environment. These signals comprise cytokines and growth factors that are synthesized as trans-membrane proteins and need to be liberated by limited proteolysis also termed ectodomain shedding. Members of the family of A disintegrin and metalloproteases (ADAM) are major mediators of ectodomain shedding and therefore initiators of paracrine signal transduction. In this review, we summarize the current knowledge on how ADAM proteases on tumour cells but also on cells of the tumour micro-environment contribute to the formation of gastrointestinal tumours, and discuss how these processes can be exploited pharmacologically.
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Wang, Qiuting, Gongming Wang, Chuyi Liu, Zuli Sun, Ruimin Li, Jiarun Gao, Mingbo Li e Leilei Sun. "The Structural Characteristics and Bioactivity Stability of Cucumaria frondosa Intestines and Ovum Hydrolysates Obtained by Different Proteases". Marine Drugs 21, n. 7 (6 luglio 2023): 395. http://dx.doi.org/10.3390/md21070395.
Abstract (sommario):
The study aimed to investigate the effects of alcalase, papain, flavourzyme, and neutrase on the structural characteristics and bioactivity stability of Cucumaria frondosa intestines and ovum hydrolysates (CFHs). The findings revealed that flavourzyme exhibited the highest hydrolysis rate (51.88% ± 1.87%). At pH 2.0, the solubility of hydrolysate was the lowest across all treatments, while the solubility at other pH levels was over 60%. The primary structures of hydrolysates of different proteases were similar, whereas the surface hydrophobicity of hydrolysates was influenced by the types of proteases used. The hydrolysates produced by different proteases were also analyzed for their absorption peaks and antioxidant activity. The hydrolysates of flavourzyme had β-fold absorption peaks (1637 cm−1), while the neutrase and papain hydrolysates had N-H bending vibrations. The tertiary structure of CFHs was unfolded by different proteases, exposing the aromatic amino acids and red-shifting of the λ-peak of the hydrolysate. The alcalase hydrolysates showed better antioxidant activity in vitro and better surface hydrophobicity than the other hydrolysates. The flavourzyme hydrolysates displayed excellent antioxidant stability and pancreatic lipase inhibitory activity during gastrointestinal digestion, indicating their potential use as antioxidants in the food and pharmaceutical industries.
17
Kriaa, Aicha, Amin Jablaoui, Héla Mkaouar, Nizar Akermi, Emmanuelle Maguin e Moez Rhimi. "Serine proteases at the cutting edge of IBD: Focus on gastrointestinal inflammation". FASEB Journal 34, n. 6 (19 aprile 2020): 7270–82. http://dx.doi.org/10.1096/fj.202000031rr.
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Shigemori, Suguru, Kazushi Oshiro, Pengfei Wang, Yoshinari Yamamoto, Yeqin Wang, Takashi Sato, Yutaka Uyeno e Takeshi Shimosato. "Generation of Dipeptidyl Peptidase-IV-Inhibiting Peptides fromβ-Lactoglobulin Secreted byLactococcus lactis". BioMed Research International 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/393598.
Abstract (sommario):
Previous studies showed that hydrolysates ofβ-lactoglobulin (BLG) prepared using gastrointestinal proteases strongly inhibit dipeptidyl peptidase-IV (DPP-IV) activityin vitro. In this study, we developed a BLG-secretingLactococcus lactisstrain as a delivery vehicle andin situexpression system. Interestingly, trypsin-digested recombinant BLG fromL. lactisinhibited DPP-IV activity, suggesting that BLG-secretingL. lactismay be useful in the treatment of type 2 diabetes mellitus.
19
Chen, Guan-Wen, e Meng-Hsuan Yang. "Production and Purification of Novel Hypocholesterolemic Peptides from Lactic Fermented Spirulina platensis through High Hydrostatic Pressure-Assisted Protease Hydrolysis". Catalysts 11, n. 8 (21 luglio 2021): 873. http://dx.doi.org/10.3390/catal11080873.
Abstract (sommario):
This research focuses on the proteolytic capacity of Spirulina platensis and their hypocholesterolemic activity via the 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGR) inhibitory activity. To select suitable proteases for releasing peptides with high HMGR-inhibiting activity from S. platensis, eight commonly used commercial proteases were used in protease hydrolysis under high hydrostatic pressure (HHP, 100 MPa or 0.1 MPa) at 50 °C for 24 h. The Peptidase R group had the highest inhibitory capacity (67%). First, S. platensis was fermented with seven mixed lactic acid bacteria for 5 h at 42 °C. This was followed by the addition of Peptidase R under high hydrostatic pressure (100 MPa at 50 °C) for 0–6 h of enzymatic hydrolysis (HHP-FH-PR6) to determine the hydrolytic capacity of S. platensis protein. As the hydrolysis time extended to 6 h, the peptide content increased from 96.8 mg/mL to 339.8 mg/mL, and the free amino acid content increased from 24 mg/mL to 115.2 mg/mL, while inhibition of HMGR increased from 67.0% to 78.4%. In an experimental simulation of in vitro gastrointestinal digestion, the IC50 of HHP-FH-PR6G on HMGR was 3.5 μg peptide/mL. Peptides with inhibitory activity on HMGR were purified, and their sequences were identified as Arg-Cys-Asp and Ser-Asn-Val (IC50: 6.9 and 20.1 μM, respectively).
20
Sabir Mustafayeva, Rugiya. "EFFECT OF STRAIN ENTEROCOCCUS FAECALIS AN1 ON RELEASE OF BIOACTIVE PEPTIDES FROM WHEY PROTEINS IN IN VITRO SIMULATED GASTROINTESTINAL CONDITIONS". NATURE AND SCIENCE 03, n. 04 (27 ottobre 2020): 64–68. http://dx.doi.org/10.36719/2707-1146/04/64-68.
Abstract (sommario):
The aim of the study was to study the potential of the proteolytic strain Enterococcus faecalis AN1 to generate inhibition of angiotensin converting enzyme (ACE), as well as to determine the effect of subsequent hydrolysis with pepsin and pancreatin in vitro simulated gastrointestinal system on this activity. Analysis of substrate hydrolysis and peptide formation was performed using SDS-PAGE and electrophoresis by RP-HPLC. Casein hydrolyzate with proteases of the strain showed the ability to produce peptides with ACE inhibition activity, which shows the use of these strains in the development of functional dairy products with antihypertensive properties. The studied strain has the potential to produce functional dairy products. Key words: lactic acid bacteria, proteases, caseins, bioactive peptides, angiotensin converting enzyme
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Aufy, Mohammed, Ahmed M. Hussein, Tamara Stojanovic, Christian R. Studenik e Mohamed H. Kotob. "Proteolytic Activation of the Epithelial Sodium Channel (ENaC): Its Mechanisms and Implications". International Journal of Molecular Sciences 24, n. 24 (16 dicembre 2023): 17563. http://dx.doi.org/10.3390/ijms242417563.
Abstract (sommario):
Epithelial sodium channel (ENaC) are integral to maintaining salt and water homeostasis in various biological tissues, including the kidney, lung, and colon. They enable the selective reabsorption of sodium ions, which is a process critical for controlling blood pressure, electrolyte balance, and overall fluid volume. ENaC activity is finely controlled through proteolytic activation, a process wherein specific enzymes, or proteases, cleave ENaC subunits, resulting in channel activation and increased sodium reabsorption. This regulatory mechanism plays a pivotal role in adapting sodium transport to different physiological conditions. In this review article, we provide an in-depth exploration of the role of proteolytic activation in regulating ENaC activity. We elucidate the involvement of various proteases, including furin-like convertases, cysteine, and serine proteases, and detail the precise cleavage sites and regulatory mechanisms underlying ENaC activation by these proteases. We also discuss the physiological implications of proteolytic ENaC activation, focusing on its involvement in blood pressure regulation, pulmonary function, and intestinal sodium absorption. Understanding the mechanisms and consequences of ENaC proteolytic activation provides valuable insights into the pathophysiology of various diseases, including hypertension, pulmonary disorders, and various gastrointestinal conditions. Moreover, we discuss the potential therapeutic avenues that emerge from understanding these mechanisms, offering new possibilities for managing diseases associated with ENaC dysfunction. In summary, this review provides a comprehensive discussion of the intricate interplay between proteases and ENaC, emphasizing the significance of proteolytic activation in maintaining sodium and fluid balance in both health and disease.
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SUHAIMI, AISHAH, AMIZA MAT AMIN, NORIZAH MHD SARBON, MOHD EFFENDY ABD. WAHID e ZALIHA HARUN. "PURIFICATION AND CHARACTERISATION OF ANGIOTENSIN I CONVERTING ENZYME (ACE) INHIBITORY PEPTIDE FROM BLOOD COCKLE (Anadara granosa) MEAT HYDROLYSATE". Malaysian Applied Biology 49, n. 1 (30 giugno 2020): 13–21. http://dx.doi.org/10.55230/mabjournal.v49i1.1649.
Abstract (sommario):
Blood cockle (Anadara granosa) is the most abundant and available bivalves in Malaysia. Blood cockles meat has high protein content and has potential to generate bioactive peptides. To date, no study has been reported on purification and identification of angiotensin I converting enzyme (ACE) inhibitory peptides from blood cockle meat. Thus, the objectives of this study were to purify and characterize ACE inhibitory peptide from blood cockle meat hydrolysate. ACE inhibitory peptides from blood cockle meat hydrolysate (CMH) were prepared by enzymatic protein hydrolysis using Protamex®. Crude CMH was characterized for its stability against gastrointestinal proteases, at varying pH (2–11) and temperature (4–90°C). Next, crude CMH was purified by ultrafiltration, ion exchange chromatography and reverse-phase chromatography and its amino acid sequence was identified. It was found that crude CMH was highly stable at low pH and temperature, and was resistant to gastrointestinal proteases (pepsin and trypsin). A three-step purification increased the inhibitory activity of CMH, reducing its IC50 from 0.35 mg/ml to 0.0094 mg/ml. The amino acid sequence of the purified peptide was determined as VNDLLSGSFKHFLY, with a molecular weight of 1621.88 Da. This study suggested the potential of ACE inhibitory peptide derived from cockle meat as a nutraceutical ingredient in functional food
23
Morgavi, D. P., K. A. Beauchemin, V. L. Nsereko, L. M. Rode, T. A. McAllister, A. D. Iwaasa, Y. Wang e W. Z. Yang. "Resistance of feed enzymes to proteolytic inactivation by rumen microorganisms and gastrointestinal proteases." Journal of Animal Science 79, n. 6 (2001): 1621. http://dx.doi.org/10.2527/2001.7961621x.
24
Farzaneh, Parisa, Morteza Khanahamadi, Mohammad Reza Ehsani e Anousheh Sharifan. "Bioactive properties of Agaricus bisporus and Terfezia claveryi proteins hydrolyzed by gastrointestinal proteases". LWT 91 (maggio 2018): 322–29. http://dx.doi.org/10.1016/j.lwt.2018.01.044.
25
Yim, Joshua J., Stefan Harmsen, Krzysztof Flisikowski, Tatiana Flisikowska, Hong Namkoong, Megan Garland, Nynke S. van den Berg et al. "A protease-activated, near-infrared fluorescent probe for early endoscopic detection of premalignant gastrointestinal lesions". Proceedings of the National Academy of Sciences 118, n. 1 (21 dicembre 2020): e2008072118. http://dx.doi.org/10.1073/pnas.2008072118.
Abstract (sommario):
Fluorescence imaging is currently being actively developed for surgical guidance; however, it remains underutilized for diagnostic and endoscopic surveillance of incipient colorectal cancer in high-risk patients. Here we demonstrate the utility and potential for clinical translation of a fluorescently labeled cathepsin-activated chemical probe to highlight gastrointestinal lesions. This probe stays optically dark until it is activated by proteases produced by tumor-associated macrophages and accumulates within the lesions, enabling their detection using an endoscope outfitted with a fluorescence detector. We evaluated the probe in multiple murine models and a human-scale porcine model of gastrointestinal carcinogenesis. The probe provides fluorescence-guided surveillance of gastrointestinal lesions and augments histopathological analysis by highlighting areas of dysplasia as small as 400 µm, which were visibly discernible with significant tumor-to-background ratios, even in tissues with a background of severe inflammation and ulceration. Given these results, we anticipate that this probe will enable sensitive fluorescence-guided biopsies, even in the presence of highly inflamed colorectal tissue, which will improve early diagnosis to prevent gastrointestinal cancers.
26
Sarker, Jyotirmoy, Pritha Das, Sabarni Sarker, Apurba Kumar Roy e A. Z. M. Ruhul Momen. "A Review on Expression, Pathological Roles, and Inhibition of TMPRSS2, the Serine Protease Responsible for SARS-CoV-2 Spike Protein Activation". Scientifica 2021 (24 luglio 2021): 1–9. http://dx.doi.org/10.1155/2021/2706789.
Abstract (sommario):
SARS-CoV-2, the coronavirus responsible for the COVID-19 pandemic, uses the host cell membrane receptor angiotensin-converting enzyme 2 (ACE2) for anchoring its spike protein, and the subsequent membrane fusion process is facilitated by host membrane proteases. Recent studies have shown that transmembrane serine protease 2 (TMPRSS2), a protease known for similar role in previous coronavirus infections, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS), is responsible for the proteolytic cleavage of the SARS-CoV-2 spike protein, enabling host cell fusion of the virus. TMPRSS2 is known to be expressed in the epithelial cells of different sites including gastrointestinal, respiratory, and genitourinary system. The infection site of the SARS-CoV-2 correlates with the coexpression sites of ACE2 and TMPRSS2. Besides, age-, sex-, and comorbidity-associated variation in infection rate correlates with the expression rate of TMPRSS2 in those groups. These findings provide valid reasons for the assumption that inhibiting TMPRSS2 can have a beneficial effect in reducing the cellular entry of the virus, ultimately affecting the infection rate and case severity. Several drug development studies are going on to develop potential inhibitors of the protease, using both conventional and computational approaches. Complete understanding of the biological roles of TMPRSS2 is necessary before such therapies are applied.
27
O'Shea, Eileen F., Paula M. O'Connor, Paul D. Cotter, R. Paul Ross e Colin Hill. "Synthesis of Trypsin-Resistant Variants of the Listeria-Active Bacteriocin Salivaricin P". Applied and Environmental Microbiology 76, n. 16 (25 giugno 2010): 5356–62. http://dx.doi.org/10.1128/aem.00523-10.
Abstract (sommario):
ABSTRACT Two-component salivaricin P-like bacteriocins have demonstrated potential as antimicrobials capable of controlling infections in the gastrointestinal tract (GIT). The anti-Listeria activity of salivaricin P is optimal when the individual peptides Sln1 and Sln2 are added in succession at a 1:1 ratio. However, as degradation by digestive proteases may compromise the functionality of these peptides within the GIT, we investigated the potential to create salivaricin variants with enhanced resistance to the intestinal protease trypsin. A total of 11 variants of the salivaricin P components, in which conservative modifications at the trypsin-specific cleavage sites were explored in order to protect the peptides from trypsin degradation while maintaining their potent antimicrobial activity, were generated. Analysis of these variants revealed that eight were resistant to trypsin digestion while retaining antimicrobial activity. Combining the complementary trypsin-resistant variants Sln1-5 and Sln2-3 resulted in a MIC50 of 300 nM against Listeria monocytogenes, a 3.75-fold reduction in activity compared to the level for wild-type salivaricin P. This study demonstrates the potential of engineering bacteriocin variants which are resistant to specific protease action but which retain significant antimicrobial activity.
28
Steinestel, Konrad, Eva Wardelmann, Wolfgang Hartmann e Inga Grünewald. "Regulators of Actin Dynamics in Gastrointestinal Tract Tumors". Gastroenterology Research and Practice 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/930157.
Abstract (sommario):
Reorganization of the actin cytoskeleton underlies cell migration in a wide variety of physiological and pathological processes, such as embryonic development, wound healing, and tumor cell invasion. It has been shown that actin assembly and disassembly are precisely regulated by intracellular signaling cascades that respond to changes in the cell microenvironment, ligand binding to surface receptors, or oncogenic transformation of the cell. Actin-nucleating and actin-depolymerizing (ANFs/ADFs) and nucleation-promoting factors (NPFs) regulate cytoskeletal dynamics at the leading edge of migrating cells, thereby modulating cell shape; these proteins facilitate cellular movement and mediate degradation of the surrounding extracellular matrix by secretion of lytic proteases, thus eliminating barriers for tumor cell invasion. Accordingly, expression and activity of these actin-binding proteins have been linked to enhanced metastasis and poor prognosis in a variety of malignancies. In this review, we will summarize what is known about expression patterns and the functional role of actin regulators in gastrointestinal tumors and evaluate first pharmacological approaches to prevent invasion and metastatic dissemination of malignant cells.
29
Krishnareddy, Suneeta, Kenneth Stier, Maya Recanati, Benjamin Lebwohl e Peter HR Green. "Commercially available glutenases: a potential hazard in coeliac disease". Therapeutic Advances in Gastroenterology 10, n. 6 (2 aprile 2017): 473–81. http://dx.doi.org/10.1177/1756283x17690991.
Abstract (sommario):
Background: The only treatment for celiac disease (CD) is a gluten-free diet (GFD). However, there is interest among patients in a medical therapy to replace or help with a GFD. Therapies include gluten-degrading enzymes (glutenases). There are glutenases available marketed as dietary supplements that have not been demonstrated to digest the toxic epitopes of gluten. Methods: We investigated the contents, claims, and disclaimers of glutenase products and assessed patient interest using Google AdWords to obtain Google search frequencies. Results: Among 14 glutenase product, all contained proteases, eight contained X-prolyl exopeptidase dipeptidyl peptidase IV, two did not state the protease contents, and eight failed to specify the name or origin of all proteases. Eleven contained carbohydrases and lipases and three probiotics. One declared wheat and milk as allergens, two contained herbal products (type not stated) and one Carica papaya. Thirteen claimed to degrade immunogenic gluten fragments, four claimed to help alleviate gastrointestinal symptoms associated with eating gluten. Disclaimers included not being evaluated by the US Food and Drug Administration and products not intended to diagnose, treat, cure, or prevent any disease. On Google AdWords, the search frequency for the product names and the search terms was 3173 searches per month. Conclusions: The names of these products make implicit claims that appear to be supported by the claims on the labels and websites for which there is no scientific basis. Google search data suggest great interest and therefore possible use by patients with CD. There needs to be greater oversight of these ‘drugs’.
30
Giangrieco, Ivana, Maria Antonietta Ciardiello, Maurizio Tamburrini, Lisa Tuppo, Adriano Mari e Claudia Alessandri. "Plant and Arthropod IgE-Binding Papain-like Cysteine Proteases: Multiple Contributions to Allergenicity". Foods 13, n. 5 (4 marzo 2024): 790. http://dx.doi.org/10.3390/foods13050790.
Abstract (sommario):
Papain-like cysteine proteases are widespread and can be detected in all domains of life. They share structural and enzymatic properties with the group’s namesake member, papain. They show a broad range of protein substrates and are involved in several biological processes. These proteases are widely exploited for food, pharmaceutical, chemical and cosmetic biotechnological applications. However, some of them are known to cause allergic reactions. In this context, the objective of this review is to report an overview of some general properties of papain-like cysteine proteases and to highlight their contributions to allergy reactions observed in humans. For instance, the literature shows that their proteolytic activity can cause an increase in tissue permeability, which favours the crossing of allergens through the skin, intestinal and respiratory barriers. The observation that allergy to PLCPs is mostly detected for inhaled proteins is in line with the reports describing mite homologs, such as Der p 1 and Der f 1, as major allergens showing a frequent correlation between sensitisation and clinical allergic reactions. In contrast, the plant food homologs are often digested in the gastrointestinal tract. Therefore, they only rarely can cause allergic reactions in humans. Accordingly, they are reported mainly as a cause of occupational diseases.
31
Nagai, T., N. Suzuki e T. Nagashima. "Antioxidative Activities and Angiotensin I-converting Enzyme Inhibitory Activities of Enzymatic Hydrolysates from Commercial Kamaboko Type Samples". Food Science and Technology International 12, n. 4 (agosto 2006): 335–46. http://dx.doi.org/10.1177/1082013206067933.
Abstract (sommario):
Enzymatic hydrolysates were prepared from commercially available kamaboko type samples using three gastrointestinal proteases and protein proteases. The yields of these hydrolysates were about 10–31% and these protein contents ranged from 62 to 533 g/mg per sample powder on their wet weight basis. The hydrolysates showed higher antioxidative activities and scavenging activities against active oxygen species such as hydroxyl radical and superoxide anion radical. Moreover, these hydrolysates exhibited high angiotensin I-converting enzyme inhibitory activites that were similar or higher than those from various fermented foods such as fish sauce, sake, soy sauce, vinegar, miso and natto. The antioxidative and antihypertensive activities of commercially available kamaboko type samples were not related to the colour of the samples. The results indicated that enzymatic hydrolysates from commercially available kamaboko type samples, whose health benefits are scientifically supported, have the potential to be an increasingly important component of a healthy lifestyle and to be beneficial to the public and the food industry.
32
Knight, Pamela A., Steven H. Wright, Catherine E. Lawrence, Yvonne Y. W. Paterson e Hugh R. P. Miller. "Delayed Expulsion of the Nematode Trichinella spiralisIn Mice Lacking the Mucosal Mast Cell–Specific Granule Chymase, Mouse Mast Cell Protease-1". Journal of Experimental Medicine 192, n. 12 (18 dicembre 2000): 1849–56. http://dx.doi.org/10.1084/jem.192.12.1849.
Abstract (sommario):
Expulsion of gastrointestinal nematodes is associated with pronounced mucosal mast cell (MMC) hyperplasia, differentiation, and activation, accompanied by the systemic release of MMC granule chymases (chymotrypsin-like serine proteases). The β-chymase mouse mast cell protease-1 (mMCP-1) is expressed predominantly by intraepithelial MMCs, and levels in the bloodstream and intestinal lumen are maximal at the time of worm expulsion in parasitized mice. To address the in vivo functions of MMC-specific β-chymases, we have generated transgenic mice that lack the mMCP-1 gene. They were backcrossed onto a congenic BALB/c background to investigate the response to nematode infection. The deletion of the mMCP-1 gene is associated with significantly delayed expulsion of Trichinella spiralis and increased deposition of muscle larvae in BALB/c mice despite the presence of normal and sometimes increased numbers of MMCs. Neither worm fecundity nor worm burdens were altered in Nippostrongylus-infected mMCP-1−/− BALB/c mice. These data demonstrate, for the first time, that the ablation of an MMC-derived effector molecule compromises the expulsion process.
33
Jiang, Weiwei, Keyu Ren, Zhiyan Yang, Zhou Fang, Yan Li, Xi Xiang e Yishan Song. "Purification, Identification and Molecular Docking of Immunomodulatory Peptides from the Heads of Litopenaeus vannamei". Foods 11, n. 20 (21 ottobre 2022): 3309. http://dx.doi.org/10.3390/foods11203309.
Abstract (sommario):
In order to realize the high-value utilization of Litopenaeus vannamei (L. vannamei) heads, immunomodulatory peptides were prepared from the enzymatic hydrolysate of L. vannamei heads, and the action mechanism of immunomodulatory peptides was determined by molecular docking. The results showed that six proteases were used to hydrolyze L. vannamei head proteins, with the animal protease hydrolysate exhibiting the highest macrophage relative proliferation rate (MRPR). The enzymatic products were then sequentially purified by ultrafiltration, Sephadex G-15 gel chromatography, identified by liquid chromatography-mass spectrometry (LC-MS/MS), and finally selected for six immunomodulatory peptides (PSPFPYFT, SAGFPEGF, GPQGPPGH, QGF, PGMR, and WQR). These peptides maintained good immune activity under heat treatment, pH treatment, and in vitro gastrointestinal digestion. Molecular docking analysis indicated that these peptides showed great binding to both toll-like receptor 2 and 4 (TLR2 and TLR4/MD-2), leading to immunomodulation. The discarded L. vannamei heads in this article are considered to be promising food-borne immunomodulators that contribute to enhancing the immune function of the body.
34
Sadeghi, Samira, Girish Vallerinteavide Mavelli, Siddhesh Sujit Vaidya e Chester Lee Drum. "Gastrointestinal Tract Stabilized Protein Delivery Using Disulfide Thermostable Exoshell System". International Journal of Molecular Sciences 23, n. 17 (30 agosto 2022): 9856. http://dx.doi.org/10.3390/ijms23179856.
Abstract (sommario):
Thermostable exoshells (tES) are engineered proteinaceous nanoparticles used for the rapid encapsulation of therapeutic proteins/enzymes, whereby the nanoplatform protects the payload from proteases and other denaturants. Given the significance of oral delivery as the preferred model for drug administration, we structurally improved the stability of tES through multiple inter-subunit disulfide linkages that were initially absent in the parent molecule. The disulfide-linked tES, as compared to tES, significantly stabilized the activity of encapsulated horseradish peroxidase (HRP) at acidic pH and against the primary human digestive enzymes, pepsin, and trypsin. Furthermore, the disulfide-linked tES (DS-tES) exhibited significant intestinal permeability as evaluated using Caco2 cells. In vivo bioluminescence assay showed that encapsulated Renilla luciferase (rluc) was ~3 times more stable in mice compared to the free enzyme. DS-tES collected mice feces had ~100 times more active enzyme in comparison to the control (free enzyme) after 24 h of oral administration, demonstrating strong intestinal stability. Taken together, the in vitro and in vivo results demonstrate the potential of DS-tES for intraluminal and systemic oral drug delivery applications.
35
Liu, Wei, Wenning Yang, Xueyan Li, Dongying Qi, Hongjiao Chen, Huining Liu, Shuang Yu, Guopeng Wang e Yang Liu. "Evaluating the Properties of Ginger Protease-Degraded Collagen Hydrolysate and Identifying the Cleavage Site of Ginger Protease by Using an Integrated Strategy and LC-MS Technology". Molecules 27, n. 15 (6 agosto 2022): 5001. http://dx.doi.org/10.3390/molecules27155001.
Abstract (sommario):
(1) Methods: An integrated strategy, including in vitro study (degree of hydrolysis (DH) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity) and in vivo study (absorption after oral administration in rats), was developed to evaluate the properties of the fish skin gelatin hydrolysates prepared using different proteases (pepsin, alkaline protease, bromelain, and ginger protease). Meanwhile, in order to identify the hydrolysis site of ginger protease, the peptides in the ginger protease-degraded collagen hydrolysate (GDCH) were comprehensively characterized by liquid chromatography/tandem mass spectrometry (LC-MS) method. (2) Results: The GDCH exhibited the highest DH (20.37%) and DPPH radical scavenging activity (77.73%), and in vivo experiments showed that the GDCH was more efficiently absorbed by the gastrointestinal tract. Further oral administration experiments revealed that GDCH was not entirely degraded to free amino acids and can be partially absorbed as dipeptides and tripeptides in intact forms, including Pro-Hyp, Gly-Pro-Hyp, and X-Hyp-Gly tripeptides. LC-MS results determined the unique substrate specificity of ginger protease recognizing Pro and Hyp at the P2 position based on the amino acids at the P2 position from the three types of tripeptides (Gly-Pro-Y, X-Hyp-Gly, and Z-Pro-Gly) and 136 identified peptides (>4 amino acids). Interestingly, it suggested that ginger protease can also recognize Ala in the P2 position. (3) Conclusions: This study comprehensively evaluated the properties of GDCH by combining in vitro and in vivo strategies, and is the first to identify the cleavage site of ginger protease by LC-MS technique. It provides support for the follow-up study on the commercial applications of ginger protease and bioactivities of the hydrolysate produced by ginger protease.
36
Kaukinen, Katri, e Katri Lindfors. "Novel Treatments for Celiac Disease: Glutenases and Beyond". Digestive Diseases 33, n. 2 (2015): 277–81. http://dx.doi.org/10.1159/000369536.
Abstract (sommario):
Currently, the only effective treatment for celiac disease is a strict lifelong gluten-free diet. However, gluten-free dieting is restrictive, difficult to maintain and nutritionally less than optimal. The improved knowledge on celiac disease pathogenesis has enabled researchers to suggest alternative strategies to treat the disorder. The drug development poses a challenge as any novel drug for celiac disease should be simultaneously effective and as safe as the gluten-free diet. The rationale behind enzyme supplementation therapy as a future treatment option for celiac patients lies in the fact that gluten is only poorly digested by gastrointestinal proteases. Due to incomplete degradation in the gastrointestinal tract, fairly long gluten peptides enter the small-intestinal lumen and come into contact with the mucosal epithelium, and in celiac disease patients this encounter launches deleterious downstream effects. Enzyme supplement therapy using either bacterial or fungal endopeptidases or proteases from germinating cereals has been proposed to promote complete digestion of prolamins and destroy disease-inducing gluten peptides. A major advantage of these glutenases is that they work in the lumen of the small intestine and do not themselves take part in the immunological cascade of events in the lamina propria, thus being unlikely to cause harmful side effects to the host. Studies to test this rationale, e.g. with Aspergillus niger prolyl endoprotease and a combination enzyme product ALV003, are already ongoing. The development of a novel medication for celiac disease is still in its early days, and thus the conventional dietary treatment will hold its place for the time being.
37
SEKI, Eiji, Katsuhiro OSAJIMA, Hiroshi MATSUFUJI, Toshiro MATSUI e Yutaka OSAJIMA. "Resistance to Gastrointestinal Proteases of the Short Chain Peptides having Reductive Effect in Blood Pressure." NIPPON SHOKUHIN KAGAKU KOGAKU KAISHI 43, n. 5 (1996): 520–25. http://dx.doi.org/10.3136/nskkk.43.520.
38
Emek, Sinan C., Hans Erik Åkerlund, Maria Clausén, Lena Ohlsson, Björn Weström, Charlotte Erlanson-Albertsson e Per-Åke Albertsson. "Pigments protect the light harvesting proteins of chloroplast thylakoid membranes against digestion by gastrointestinal proteases". Food Hydrocolloids 25, n. 6 (agosto 2011): 1618–26. http://dx.doi.org/10.1016/j.foodhyd.2010.12.004.
39
Bassetto, C. C., e A. F. T. Amarante. "Vaccination of sheep and cattle against haemonchosis". Journal of Helminthology 89, n. 5 (20 aprile 2015): 517–25. http://dx.doi.org/10.1017/s0022149x15000279.
Abstract (sommario):
AbstractVaccines against gastrointestinal nematodes are one potential option for the control of parasitic gastroenteritis in ruminants. Excretory/secretory (E/S) and hidden antigens are being studied as candidates for vaccines against Haemonchus spp., which is a major parasite in cattle and small ruminants that are raised in warm climates. Protection has been observed after vaccination with some E/S proteases, particularly cysteine proteases and with some glycans that are abundant on the surfaces and in the secretory products of helminths. However, the most promising results are being obtained with glycoprotein antigens extracted from the microvillar surfaces of the Haemonchus contortus intestinal cells. These antigens are called ‘hidden′ because they are not exposed to the host's immune system during infection. Thus far, recombinant forms of these antigens have not been usefully protective. However, because only 5 μg of antigen is required per dose, production of a native antigen vaccine from adult parasites has been found to be practical and commercially viable. Trials indicate that a vaccine made from one particular isolate will cross-protect against geographically distant isolates.
40
Kyriazakis, Ilias, Jos Houdijk e Bob Coop. "Immunonutrition: the nutritional control of acquired immunity to parasites". Proceedings of the British Society of Animal Science 2002 (2002): 232. http://dx.doi.org/10.1017/s1752756200008887.
Abstract (sommario):
How do animal hosts control worms? When an animal ingests an infective form of a gastrointestinal helminth (roundworm) from pasture, it can contain the infection by limiting the establishment, growth rate, fecundity and persistence of the parasite. This containment is achieved through the direct and indirect actions of the immune response. A helminth-specific immune response is, by and large, a local one and is achieved by an increase in the number of effector cells and the concentration of effector substances (such as specific immunoglobulins, proteases and mucin) in the gastrointestinal mucosa and lumen. The delivery of some of the effector substances is achieved through plasma leakage, part of which is irretrievably lost As these responses require nutrients for their expression and replenishment, it is not unreasonable to expect that host nutrition has the potential to affect the immune responses when nutrient resources are scarce. In this presentation we concentrate on the consequences of nutrition on the acquired immunity to parasites. Host nutrition can also affect innate immunity by, for example, making the gastrointestinal environment more hostile to parasites, but such effects will not be considered any further here.
41
Kontos, Christos K., Konstantinos Mavridis, Maroulio Talieri e Andreas Scorilas. "Kallikrein-related peptidases (KLKs) in gastrointestinal cancer: Mechanistic and clinical aspects". Thrombosis and Haemostasis 110, n. 09 (2013): 450–57. http://dx.doi.org/10.1160/th12-11-0791.
Abstract (sommario):
SummaryThe human tissue kallikrein (KLK1) and kallikrein-related peptidases (KLKs) are secreted serine proteases with diverse expression patterns and physiological roles in different systems, including the digestive system. The aberrant expression of KLKs in gastrointestinal malignancies as well as their implication in carcinogenesis including cell growth regulation, angiogenesis, invasion, and metastasis, has prompted scientists to investigate their potential as cancer biomarkers. Expression of distinct KLKs is associated with various clinic-pathological parameters of patients with gastric, colorectal, pancreatic, hepatic, and esophageal cancer. Moreover, several KLKs possess significant favourable or unfavourable prognostic value in these human malignancies. Identification of novel diagnostic, prognostic and predictive biomarkers will contribute utmost to clinical decision-making, since early diagnosis of gastrointestinal cancer and early detection of recurrence following surgery are critical for the effective treatment of patients and for a positive clinical outcome. The current review provides a brief overview of the functional role of KLKs in gastric, colorectal, pancreatic, hepatic, and esophageal cancer, and describes the current status of KLKs as potential tumour biomarkers in these human malignancies.
42
Jayne, D. G. "The Molecular Biology of Peritoneal Carcinomatosis from Gastrointestinal Cancer". Annals of the Academy of Medicine, Singapore 32, n. 2 (15 marzo 2003): 219–25. http://dx.doi.org/10.47102/annals-acadmedsg.v32n2p219.
Abstract (sommario):
Introduction: Peritoneal carcinomatosis is a frequent form of disease progression in gastrointestinal cancer, and all too often is a preterminal event with a median survival of only 6 months. Despite the introduction of aggressive surgical and chemotherapeutic approaches, any significant improvement in survival is unlikely until we better understand the molecular biology of peritoneal metastasis. Methods: A Medline search and review of references was undertaken to identify all manuscripts in the English language concerned with peritoneal metastasis from gastrointestinal cancer. Results: Peritoneal carcinomatosis involves a complex sequence of interdependent steps. The injured peritoneum is a rich source of cytokines and growth factors that facilitate tumour proliferation and invasion in the postoperative abdomen. Peritoneal tumour adhesion is dependent on adhesion molecules, such as CD44, and the ß-1 integrins. Invasion of the mesothelium involves, at least in part, a process of tumour-induced mesothelial apoptosis. Matrix metalloproteinases, such MMP-7, facilitate stromal invasion, but the role of other proteases ininvasion remains to be elucidated. To date, the significance of angiogenesis in the peritoneal metastatic cascade is unknown. Conclusion: The molecular biology of peritoneal carcinomatosis is only just beginning to be understood. Further research into the mediators of the peritoneal metastatic cascade is needed if more effective therapeutic strategies are to be developed for this invariably fatal, yet unfortunately common, condition.
43
Hanning, Nikita, Michelle De bruyn, Hannah Ceuleers, Tim Boogaerts, Maya Berg, Annemieke Smet, Heiko U. De Schepper et al. "Local Colonic Administration of a Serine Protease Inhibitor Improves Post-Inflammatory Visceral Hypersensitivity in Rats". Pharmaceutics 13, n. 6 (29 maggio 2021): 811. http://dx.doi.org/10.3390/pharmaceutics13060811.
Abstract (sommario):
Dysregulation of the protease–antiprotease balance in the gastrointestinal tract has been suggested as a mechanism underlying visceral hypersensitivity in conditions such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS). We aimed to study the potential therapeutic role of an intracolonically administered serine protease inhibitor for the treatment of abdominal pain in a post-inflammatory rat model for IBS. An enema containing 2,4,6-trinitrobenzene sulfonic acid (TNBS) was used to induce colitis in male Sprague–Dawley rats, whereas controls received a saline solution. Colonoscopies were performed to confirm colitis and follow-up mucosal healing. In the post-inflammatory phase, the serine protease inhibitor UAMC-00050 (0.1–5 mg/kg) or its vehicle alone (5% DMSO in H2O) was administered in the colon. Thirty minutes later, visceral mechanosensitivity to colorectal distensions was quantified by visceromotor responses (VMRs) and local effects on colonic compliance and inflammatory parameters were assessed. Specific proteolytic activities in fecal and colonic samples were measured using fluorogenic substrates. Pharmacokinetic parameters were evaluated using bioanalytical measurements with liquid chromatography–tandem mass spectrometry. Post-inflammatory rats had increased trypsin-like activity in colonic tissue and elevated elastase-like activity in fecal samples compared to controls. Treatment with UAMC-00050 decreased trypsin-like activity in colonic tissue of post-colitis animals. Pharmacokinetic experiments revealed that UAMC-00050 acted locally, being taken up in the bloodstream only minimally after administration. Local administration of UAMC-00050 normalized visceral hypersensitivity. These results support the role of serine proteases in the pathophysiology of visceral pain and the potential of locally administered serine protease inhibitors as clinically relevant therapeutics for the treatment of IBS patients with abdominal pain.
44
Fernández-Pérez, Silvia, Jenifer Pérez-Andrés, Sergio Gutiérrez, Nicolás Navasa, Honorina Martínez-Blanco, Miguel Ángel Ferrero, Santiago Vivas et al. "The Human Digestive Tract Is Capable of Degrading Gluten from Birth". International Journal of Molecular Sciences 21, n. 20 (18 ottobre 2020): 7696. http://dx.doi.org/10.3390/ijms21207696.
Abstract (sommario):
The human gastrointestinal system has the capacity to metabolize dietary gluten. The capacity to degrade gliadin-derived peptide is present in humans from birth and increases during the first stages of life (up to 6–12 months of age). Fecal samples from 151 new-born and adult non-celiac disease (NCD) volunteers were collected, and glutenase and glianidase activities were evaluated. The capacity of total fecal proteins to metabolize 33-mer, 19-mer, and 13-mer gliadin peptides was also evaluated by high-performance liquid chromatography (HPLC). Feces from new-borns (meconium) showed glutenase and gliadinase activities, and peptidase activity against all three gliadin peptides. Maximal gluten degradative activity was observed in fecal samples from the youngest volunteers (0–12 months old). After the age of nine months, the gluten digestive capacity of gastrointestinal tract decreases and, from ±8 years old, individuals lose the ability to completely degrade toxic peptides. The gastrointestinal proteases involved in gluten digestion: elastase 2A, elastase 3B, and carboxipeptidase A1 are present from earlier stages of life. The human digestive tract contains the proteins capable of metabolizing gluten from birth, even before starting gluten intake. Humans are born with the ability to digest gluten and to completely degrade the potentially toxic gliadin-derived peptides (33-, 19-, and 13-mer).
45
Nielsen, Søren, Stig Purup e Lotte Larsen. "Effect of Casein Hydrolysates on Intestinal Cell Migration and Their Peptide Profiles by LC-ESI/MS/MS". Foods 8, n. 3 (6 marzo 2019): 91. http://dx.doi.org/10.3390/foods8030091.
Abstract (sommario):
Potential beneficial effects of bioactive peptides derived from casein on epithelial cellular wound healing in the gastrointestinal tract were studied. Bovine casein was digested by a combination of pepsin and pancreatic proteases at different time intervals to represent ranges of duration of gastrointestinal digestion. Intestinal epithelial cells were used as an in vitro model of the small intestine. The effect of casein hydrolysates on cell migration was studied by scratch assay as a model of wound healing. Casein digested by pepsin and pancreatin for 10 to 30 min were found to have a significant stimulatory effect of >40% on cell migration relative to the control. A potential effect of casein gastrointestinal digests on gastro-intestinal wound healing has not previously been reported. The peptide profiles of active as well as inactive casein hydrolysates were characterised by liquid chromatography coupled to ion trap tandem mass spectrometry. By comparison of identified peptides in active and inactive casein hydrolysates, a pool of 11 peptides derived from casein were identified as potential candidates for effects on cell migration. Searching the milk bioactive peptide database (MBPDB) showed that 15 of the identified peptides had known biological functions such as antimicrobial, antioxidant, and immunomodulatory activity.
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Hung, Wei-Ting, Christoper Caesar Yudho Sutopo, Mei-Li Wu e Jue-Liang Hsu. "Discovery and Characterization of a Dual-Function Peptide Derived from Bitter Gourd Seed Protein Using Two Orthogonal Bioassay-Guided Fractionations Coupled with In Silico Analysis". Pharmaceuticals 16, n. 11 (20 novembre 2023): 1629. http://dx.doi.org/10.3390/ph16111629.
Abstract (sommario):
The hydrolysate of bitter gourd seed protein, digested by the combined gastrointestinal proteases (BGSP-GPs), exhibited the most potent inhibition on angiotensin-I-converting enzyme (ACE) with an IC50 value of 48.1 ± 2.0 µg/mL. Using two independent bioassay-guided fractionations, fraction F5 from reversed-phase chromatography and fraction S1 from strong cation exchange chromatography exhibited the highest ACE inhibitory (ACEI) activity. Three identical peptides were simultaneously detected from both fractions and, based on the in silico appraisal, APLVSW (AW6) was predicted as a promising ACEI peptide. Their dipeptidyl peptidase-IV (DPP4) inhibitory (DPP4I) activity was also explored. The IC50 values of AW6 against ACE and DPP4 were calculated to be 9.6 ± 0.3 and 145.4 ± 4.4 µM, respectively. The inhibitory kinetics and intermolecular interaction studies suggested that AW6 is an ACE competitive inhibitor and a DPP4 non-competitive inhibitor. The quantities of AW6 in BGSP-GP hydrolysate, fractions F5 and S1, were also analyzed using liquid chromatography–tandem mass spectrometry. Notably, AW6 could resist hydrolysis in the human gastrointestinal tract according to the result of the simulated gastrointestinal digestion. To the best of our knowledge, this is the first discovery and characterization of a dual-function (ACEI and DPP4I activities) peptide derived from bitter gourd seed protein.
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Seki, Eiji, Katsuhiro Osajima, Hiroshi Matsufuji, Toshiro Matsui e Yutaka Osajima. "Val-Tyr, an Angiotensin I Converting Enzyme Inhibitor from Sardines that have Resistance to Gastrointestinal Proteases". Nippon Nōgeikagaku Kaishi 69, n. 8 (1995): 1013–20. http://dx.doi.org/10.1271/nogeikagaku1924.69.1013.
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Vertiprakhov, V. G., e A. A. Grozina. "EXOCRINE PANCREATIC FUNCTION IN CHICKENS AS A RESULT OF ADDING FEED ACIDIFIERS IN THEIR DIET". Siberian Herald of Agricultural Science 48, n. 6 (24 gennaio 2019): 63–69. http://dx.doi.org/10.26898/0370-8799-2018-6-9.
Abstract (sommario):
Feed acidifiers are used in animal diets for the prevention of proliferation of intestinal pathogenic microorganisms and resulting gastrointestinal digestive disorders. These additives, containing organic acids, have also been found to improve productivity and feed efficiency in poultry. There is information about correlation between digestive enzymes’ activity and intestinal microbiota of meattype chickens. However, the exact mechanism of the beneficial impact of organic acids on the digestion system still remains understudied. The paper presents the results of experiments conducted on Hisex White chicken with chronic fistulae of the main pancreatic duct, fed on a diet supplemented with an acidifier containing 2-furoic acid. No significant effect of this acidifier was found on the digestive pancreatic function. The dynamics analysis showed that the chickens’ secretion rate of pancreatic juice after postprandial 30 minutes dropped by over two times in the testing period when using acidifiers in their diet. After 150 minutes this rate was lower by 27.3% compared to the control group, which corresponds the neurochemical phase of secretory regulation. Analysis of enzyme dynamics (amylase, lipase and protease) showed a slight increase in the activity of proteases in pancreatic juice (by 1.2- 12.4%), compared to the control group, in the phase of complex-reflex regulation of pancreatic secretory activity related to the recognition of the taste qualities of the feed. Feed conversion ratio in the test group of broiler chickens increased by 1.52% when using acidifiers in the diet. The result of the study showed that the use of acidifiers has a beneficial effect on chickens’ gastrointestinal digestion as well as an inhibitive action on intestinal pathogens.
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Zambon, Maria C. "Epidemiology and pathogenesis of influenza". Journal of Antimicrobial Chemotherapy 44, suppl_2 (1 novembre 1999): 3–9. http://dx.doi.org/10.1093/jac/44.suppl_2.3.
Abstract (sommario):
Abstract Influenza A, B and C all have a segmented genome, although only certain influenza A subtypes and influenza B cause severe disease in humans. The two major proteins of influenza are the surface glycoproteins—haemagglutinin (HA) and neuraminidase (NA). HA is the major antigen for neutralizing antibodies and is involved in the binding of virus particles to receptors on host cells. Pandemics are a result of novel virus subtypes of influenza A, created by reassortment of the segmented genome (antigenic shift), whereas annual epidemics are a result of evolution of the surface antigens of influenza A and B virus (antigenic drift). The rapid evolution of influenza viruses highlights the importance of surveillance in identifying novel circulating strains. Infectivity of influenza depends on the cleavage of HA by specific host proteases, whereas NA is involved in the release of progeny virions from the cell surface and prevents clumping of newly formed virus. In birds, the natural hosts of influenza, the virus causes gastrointestinal infection and is transmitted via the faeco-oral route. Virulent avian influenza strains, which cause systemic disease, have an HA that is cleaved by proteases present in all cells of the body, rather than by proteases restricted to the intestinal tract. In mammals, replication of influenza subtypes appears restricted to respiratory epithelial cells. Most symptoms and complications, therefore, involve the respiratory tract. However, systemic complications are sometimes observed and other viral genes besides the HA, including the NA, may be involved in determination of virulence of influenza strains in mammals.
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López-Expósito, Iván, María Asunción Manso, Rosina López-Fandiño e Isidra Recio. "Activity against Listeria monocytogenes of human milk during lactation. A preliminary study". Journal of Dairy Research 75, n. 1 (29 gennaio 2008): 24–29. http://dx.doi.org/10.1017/s0022029907002993.
Abstract (sommario):
Human milk samples from three healthy donors were investigated in order to evaluate the antibacterial activity during lactation against Escherichia coli ATCC 25922 and Listeria monocytogenes. The concentration of the main human-milk antimicrobial proteins (lactoferrin (LF), lysozyme (LZ) and secretory immunoglobulin A (sIgA)) was determined by ELISA. Results showed that human milk exhibited antibacterial activity against List. monocytogenes, although it was weakly active against Esch. coli ATCC 25922. The observed antilisterial activity was positively correlated with LZ concentration. In addition, the effect of gastrointestinal proteases, at different pH conditions, that prevail in the stomach of infants (pH 2·0–6·5), on antilisterial activity and protein degradation was evaluated. Hydrolysis with pepsin at pH 4·0–6·5, followed by treatment with pancreatic enzymes, resulted in a decreased hydrolysis of LZ, LF and sIgA and an enhanced antibacterial activity against List. monocytogenes. It is suggested that partial degradation of certain milk proteins at the gastrointestinal level may produce peptides that could act synergistically with the remnant intact proteins.