Littérature scientifique sur le sujet « Matrix Metalloproteinase NAFLD »

Undiagnosed and untreated non-alcoholic fatty liver disease (NAFLD) can lead to the development of many complications, such as cirrhosis, hepatocellular carcinoma, or cardiovascular diseases. Obese people are at increased risk of developing NAFLD. Due to the current lack of routine diagnostics, it is extremely important to look for new diagnostic methods and markers for this disease. The aim of this study was to assess the concentration of selected pro-inflammatory adipokines and cytokines in the unstimulated saliva of obese people with fatty liver disease in various stages (with or without slight fibrosis) and to analyze them for possible use as early markers of NAFLD diagnosis. The study involved 96 people who were divided into 5 groups based on the criterion of body mass index (BMI) and the degree of fatty liver (liver elastography). There were statistically significant differences between the groups in the concentrations of MMP-9 (matrix metalloproteinase 9), resistin, and IL-1β (interleukin 1β) in saliva. Statistically significant, positive correlations between hepatic steatosis and the concentration of MMP-2 (matrix metalloproteinase 2), resistin, and IL-1β in saliva were also found. Statistically significant positive correlations were also found between the concentration of resistin in saliva and the concentration of ALT (alanine aminotransferase) and GGTP (gamma-glutamyl transpeptidase) in serum. MMP-2, IL-1β, and resistin may be potential markers of NAFLD development, assessed in saliva. However, further research is needed because this is the first study to evaluate the concentrations of the selected pro-inflammatory parameters in the saliva of patients with NAFLD.

Non-alcoholic fatty liver disease (NAFLD) is by far the most common form of chronic liver disease worldwide, affecting adults as well as children. Under the term of NAFLD there is a wide spectrum of diseases ranging from simple steatosis to the non-alcoholic steatohepatitis (NASH), which can progress to cirrhosis and hepatocellular carcinoma (HCC). Several mechanisms have been described to influence the progression of the disease from the benign NAFL to the aggressive NASH. The imbalance between pro- and anti-oxidant mechanisms and between pro- and anti-inflammatory cytokines is thought to play a pivotal role in the pathogenesis of NAFLD and disease progression toward NASH and fibrosis. The present review intends to look at some of the mechanistic biomarkers to be employed in establishing an early diagnosis in HCC derived from NASH.Abbreviations: ANGPT: angiopoietin-2; AFP: α-fetoprotein; ALT: alanine aminotransferase; AST: aspartate aminotransferase; CI: confidence interval; COL: collagen; DCP: des-carboxyprothrombin; γGT: gamma glutamyl transpeptidase; HBV: hepatitis B virus; HCC: hepatocellular carcinoma; HCV: hepatitis C virus; HR: hazard ratio; ITG: integrin; LAM: laminin collagen genes; MMP: matrix metalloproteinase; MS: metabolic syndrome; NAFLD: non-alcoholic fatty liver disease; NASH: non-alcoholic steatohepatitis; PDGFRA: platelet derived growth factor receptor-α

Aim. To estimate the diagnostic and informative value of clinical and laboratory parameters in the development and progression of liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) to enhance efficiency of their treatment. Subjects and methods. An open-label case-control study included 77 patients with NAFLD. Clinical and laboratory examinations were done. To search for additional noninvasive fibrosis markers, the investigators studied the serum concentrations of insulin, leptin, adiponectin, matrix metalloproteinase-9 (MMP-9) and its inhibitors, such as tissue inhibitor of matrix metalloproteinases 1 (TIMP-1) and TIMP-2. All the patients underwent elastometry to assess the degree of liver fibrosis with the Metavir scale with the use of a Fibroscan machine. Results. The serum levels of low-density lipoproteins, glucose, MMP-9, and leptin proved to be most informative in assessing the progression of the initial stages (1-2) of fibrosis, as were the increased liver size detected by physical examination, systolic blood pressure, carbohydrate metabolic disorders, alanine/aspartate aminotransferase levels, waist-to-hip ratio, TIMP-1, and TIMP-2 in evaluating the progression of Stage II fibrosis 2 to Stage 3. Conclusion. The clinical and laboratory parameters can serve as reliable noninvasive markers that reflect the progression of fibrotic changes in liver tissue.

Abstract Objectives Recently fructose has been linked to the development of Nonalcoholic Fatty Liver Disease (NAFLD), but the mechanisms behind the progression remain to be elucidated. Kupffer cells have been identified as regulators of hepatic inflammation and extracellular matrix (ECM) proteins. Activated macrophages are known to express tissue inhibitor of metalloproteinase (TIMP1), which inhibits matrix metalloproteinase 9 (MMP9) activity of reconstructing ECM which leads to fibrosis. In humans and mouse models, TIMP1 expression is positively correlated with the progression of NAFLD. Based on these findings, we hypothesize that fructose regulates TIMP1 gene expression in activated proinflammatory macrophages. Methods Using an in vitro model of J774 macrophages and primary Kupffer cells, cells were treated to induce an M1 phenotype in the presence of glucose or fructose. Cells were harvested for RNA and RT-PCR was conducted to measure ECM gene expression. Isolated Kupffer cells were collected from C57BL/6J mice fed a high fat diet (HFD) supplemented with 30% fructose or 30% glucose and analyzed for ECM expression. To examine fructose uptake and intra- and extracellular metabolites, mass spectrophotometry and nuclear magnetic resonance was conducted. Results Timp1 gene expression was significantly increased in J77.4 cells treated with fructose compared to glucose. Surprisingly, fructose treatment decreased Mmp9 gene expression. Likewise, fructose treatment increased TIMP1 protein expression in isolated Kupffer cells. In vivo, isolated hepatic macrophages from mice fed HF and high fructose diet had elevated Timp1 gene expression compared to mice fed high glucose diet. Extracellular levels of lactate decreased by 1.5-fold in fructose treated J77.4 cells compared to glucose. Metabolites involved in the TCA cycle and mitochondrial function were decreased when treated with fructose compared to glucose in non-activated macrophages. However, fructose treatment increased intracellular methanol and acetate levels in M1 macrophages compared to glucose. Conclusions Our data suggest that fructose upregulates Timp1 expression and possibly decreases mitochondrial function while increasing acetate and methanol production, identifying new mechanisms by which fructose drives the progression of NAFLD. Funding Sources Kenan Institute North Carolina University.

Objective To examine the effects of arnebin-1 on nonalcoholic fatty liver disease (NAFLD) induced by a high-fat diet (HFD). Methods Male Sprague–Dawley rats were fed an HFD for 10 weeks and then treated with arnebin-1 at a dose of 5, 10 or 20 mg/kg/day by gavage for a further 12 weeks of a 22-week HFD. Peripheral blood and liver tissues were collected for biochemical and histopathological examination. The mechanisms of arnebin-1 on liver fibrosis and insulin resistance (IR) were determined by Western blotting and real-time quantitative polymerase chain reaction. Results Arnebin-1 treatment attenuated the increase of total cholesterol, triglycerides, low-density lipoprotein cholesterol, aspartate aminotransferase and alanine aminotransferase in serum and lipid accumulation in the livers of HFD-fed rats. Furthermore, arnebin-1 abrogated HFD-induced liver fibrosis and the increase of fibrotic biomarkers. The HFD-induced decrease of hepatic proliferator-activated receptor γ and pro-matrix-metalloproteinase (MMP)-9 levels and the increase of tissue inhibitor of metalloproteinase-1 (TIMP-1) levels were reversed after arnebin-1. Arnebin-1 attenuated IR through activating the insulin receptor substrate-1/Akt/mTOR signalling pathway. Conclusion This study demonstrated that arnebin-1 ameliorates NAFLD, in part, by attenuating hepatic fibrosis and IR, suggesting that arnebin-1 may be a therapeutic agent for NAFLD treatment.

IntroductionThe non-invasive enhanced liver fibrosis (ELF) score—comprising tissue inhibitor of matrix metalloproteinases-1 (TIMP1), hyaluronic acid (HA) and amino-terminal propeptide of type III procollagen (PIIINP)—has been shown to accurately predict fibrosis stages among patients with non-alcoholic fatty liver disease (NAFLD). However, no study has examined whether the ELF score or its components would also be predictive of type 2 diabetes, which commonly coexists and shares the same pathogenic abnormalities with NAFLD. Therefore, we prospectively investigated their associations with type 2 diabetes risks for the first time.Research design and methodsThe ELF score was measured among 254 type 2 diabetes cases and 254 age-matched and sex-matched controls nested within the prospective Singapore Chinese Health Study. Cases had hemoglobin A1c (HbA1c) levels <6.5% at blood collection (1999–2004) and reported to have diabetes during follow-up II (2006–2010). Controls had HbA1c levels <6.0% at blood-taking and remained free of diabetes at follow-up II. Multivariable conditional logistic regression models were used to assess the ELF-diabetes association.ResultsHigher TIMP1 levels were associated with increased type 2 diabetes risk, and the OR comparing the highest versus lowest quartiles was 2.56 (95% CI 1.23 to 5.34; p trend=0.035). However, ELF score, PIIINP and HA were not significantly associated with type 2 diabetes risks.ConclusionsHigher TIMP1 levels, but not ELF score, PIIIMP and HA, were associated with increased type 2 diabetes risk in Chinese adults. Our results suggested that elevated TIMP1 levels may contribute to the type 2 diabetes development through pathways other than liver fibrosis.

Background/Aims Non-alcoholic fatty liver disease (NAFLD) represents a significant public health issue. Identifying patients with simple steatosis from those with non-alcoholic steatohepatitis (NASH) is crucial since NASH is correlated with increased morbidity and mortality. Serum-based markers, including adipokines and cytokines, are important in the pathogenesis and progression of NAFLD. Here we assessed the usefulness of such markers in patients with NAFLD. Methods This prospective, cross-sectional study included 105 adult patients with varying severity of NAFLD. Twelve serum-based markers were measured by 3 biochip platforms and 2 enzyme-linked immunosorbent assay (ELISA) methods. We also developed a NAFLD individual fibrosis index (NIFI) using the serum-based markers mostly correlated with fibrosis severity. Results Sixty-one out of 105 patients were male (58.1%) with mean age was 53.5 years. Higher Interleukin-6 (IL-6) increased (p = 0.0321) and lower Matrix Metalloproteinase-9 (MMP-9) serum levels (p = 0.0031) were associated with higher fibrosis as measured by Fibroscan® in multivariable regression analysis. Using receiver-operating characteristic (ROC) curve analysis for the NIFI, area under the curve for predicting Fibroscan values ≥ 7.2 kPa was 0.77 (95%CI: 0.67, 0.88, p<0.001), with sensitivity of 89.3%, specificity of 57.9% and a positive likelihood ratio of 2.8. Conclusions Increasing fibrosis severity in NAFLD is associated with differential expression of IL-6 and MMP-9. NIFI could be valuable for the prediction of advanced NAFLD fibrosis and potentially help avoid unnecessary interventions such as liver biopsy in low-risk patients.

Non-alcoholic fatty liver disease (NAFLD) is a liver pathology affecting around 25% of the population worldwide. Excess oxidative stress, inflammation and aberrant cellular signaling can lead to this hepatic dysfunction and eventual carcinoma. Molecular hydrogen has been recognized for its selective antioxidant properties and ability to attenuate inflammation and regulate cellular function. We administered hydrogen-rich water (HRW) to 30 subjects with NAFLD in a randomized, double-blinded, placebo-controlled manner for eight weeks. Phenotypically, we observed beneficial trends (p > 0.05) in decreased weight (≈1 kg) and body mass index in the HRW group. HRW was well-tolerated, with no significant changes in liver enzymes and a trend of improved lipid profile and reduced lactate dehydrogenase levels. HRW tended to non-significantly decrease levels of nuclear factor kappa B, heat shock protein 70 and matrix metalloproteinase-9. Interestingly, there was a mild, albeit non-significant, tendency of increased levels of 8-hydroxy-2’-deoxyguanosine and malondialdehyde in the HRW group. This mild increase may be indicative of the hormetic effects of molecular hydrogen that occurred prior to the significant clinical improvements reported in previous longer-term studies. The favorable trends in this study in conjunction with previous animal and clinical findings suggest that HRW may serve as an important adjuvant therapy for promoting and maintaining optimal health and wellness. Longer term studies focused on prevention, maintenance, or treatment of NAFLD and early stages of NASH are warranted.

Nowadays, the nonalcoholic fatty liver disease represents the main chronic liver disease in the Western countries, and the correct medical therapy remains a big question for the scientific community. The aim of our study was to evaluate the effect derived from the administration for six months of silybin with vitamin D and vitamin E (RealSIL 100D®) on metabolic markers, oxidative stress, endothelial dysfunction, and worsening of disease markers in nonalcoholic fatty liver disease patients. We enrolled 90 consecutive patients with histological diagnosis of nonalcoholic fatty liver disease and 60 patients with diagnosis of reflux disease (not in therapy) as healthy controls. The nonalcoholic fatty liver disease patients were randomized into two groups: treated (60 patients) and not treated (30 patients). We performed a nutritional assessment and evaluated clinical parameters, routine home tests, the homeostatic model assessment of insulin resistance, NAFLD fibrosis score and fibrosis-4, transient elastography and controlled attenuation parameter, thiobarbituric acid reactive substances, tumor necrosis factor α, transforming growth factor β, interleukin-18 and interleukin-22, matrix metalloproteinase 2, epidermal growth factor receptor, insulin growth factor-II, cluster of differentiation-44, high mobility group box-1, and Endocan. Compared to the healthy controls, the nonalcoholic fatty liver disease patients had statistically significant differences for almost all parameters evaluated at baseline (p<0.05). Six months after the baseline, the proportion of nonalcoholic fatty liver disease patients treated that underwent a statistically significant improvement in metabolic markers, oxidative stress, endothelial dysfunction, and worsening of disease was greater than not treated nonalcoholic fatty liver disease patients (p<0.05). Even more relevant results were obtained for the same parameters by analyzing patients with a concomitant diagnosis of metabolic syndrome (p<0.001). The benefit that derives from the use of RealSIL 100D could derive from the action on more systems able to advance the pathology above all in that subset of patients suffering from concomitant metabolic syndrome.

L’obésité est un problème majeur de santé publique en France puisque 50% de la population est en surpoids ou obèse. Plusieurs complications hépatiques de l’obésité existent dont la NASH, pathologie caractérisée par l’association de lésions de stéatose et d’hépatite, d’anomalies des tests hépatiques. Chez un tiers des patients, la NASH conduit à l’apparition d’une fibrose puis d’une cirrhose. Elle favorise l’apparition du carcinome hépatocellulaire.La physiopathologie de la NASH est caractérisée par une dérégulation du métabolisme lipidique qui conduit à l’accumulation de lipides au niveau des hépatocytes. Celle-ci est toxique. La composition et le rôle des lipides comme promoteur de la NASH est de plus en plus étudié.Le premier volet de la thèse concerne la mise en évidence de marqueurs diagnostiques de la NASH. Dans cette étude, nous avons établi pour la première fois une signature lipidique de la NASH sur la base de la quantification de 32 lipides. Aucun des lipides identifiés ne permettait par lui-même de discriminer la stéatose de la NASH.En revanche, la signature lipidique globale permettait de distinguer les témoins patients des NAFL et des NASH. Nous avons également mis en évidence une dérégulation de la voie métabolique impliquée dans la synthèse des acides gras dans la NASH.Le deuxième volet avait pour objectif l’identification de nouveaux marqueurs pronostiques de la NASH. L'analyse par microarray d'expression de gènes a montré 1549 gènes discriminant les patients ayant une stéatopathie, NAFL ou NASH, des obèses sains ou des contrôle. Parmi eux, 58 gènes discriminaient la NASH de la stéatose simple. Ces gènes étaient impliqués dans le remodelage de la matrice extracellulaire et l'inflammation. Le gène le plus discriminant était FABP4. Parmi les gènes fortement associés à une expression élevée de FABP4, la métalloprotéinase MMP9 était surexprimée chez 55% des patients NASH. Nous avons identifié un total de 330 gènes régulés de manière différentielle, dont 229 gènes étaient surexprimés chez des patients NASH présentant un niveau d'expression élevé de MMP9. En utilisant les niveaux d'expression génique des gènes FABP4 et MMP9 hépatiques comme indicateurs de la progression de la maladie dans une cohorte indépendante de patients atteints de NAFLD, nous avons identifié les patients atteints de NAFL et NASH susceptibles d'avoir un mauvais pronostic.Enfin, dans le troisième volet, nous nous sommes intéressés à la valeur diagnostique et pronostique de la stéatose des greffons hépatiques, mesurée par FTIR. En effet, la stéatose en particulier lorsqu’elle dépasse 60% et macrovacuolaire, est connue pour impacter significativement la fonction et la survie des greffons hépatiques. Dans notre étude, parmi 58 prélèvements de greffons, le pourcentage moyen de stéatose macrovacuolaire et de stéatose microvésiculaire, évalué par le pathologiste, était de 2% à 30%, respectivement. La concentration moyenne en triglycérides hépatiques mesurée par chromatographie couplée en phase gazeuse à la spectrométrie était de 214 nmol/mg de tissu hépatique. L'estimation de la teneur en triglycérides obtenue par FTIR était significativement corrélée (r2 = 0,812) avec les résultats de la concentration moyenne en triglycérides hépatiques mesurée par chromatographie couplée en phase gazeuse à la spectrométrie. Trente-quatre (58%) patients ont présenté des complications définies par un stade Dindo-Clavien ≥2, dont 2 non-fonction primaire du greffon et 5 décès. Le seuil le plus discriminant entre le niveau de triglycérides et l’échec de la TH était de 54,02 nmol/mg de tissu hépatique obtenu par FTIR. La quantification du contenu hépatique en triglycérides par GC/MS était significativement associée à la survie du patient à la fin du suivi (p<0,0001) et à un échec de la transplantation (p <0,0001). L'estimation du contenu hépatique en triglycérides à l'aide de FTIR était significativement associée à la survie après greffe d'un an (p<0,0001)
Obesity is a major public health problem in France since 50% of the population has overweight. Several hepatic complications of obesity exist including NASH, pathology characterized by the combination of histological lesions of hepatic steatosis and hepatitis, liver test abnormalities and the absence of known liver disease, particularly toxic (alcohol) or virus. In one third of patients, NASH leads to fibrosis and then cirrhosis. It also promotes the development of hepatocellular carcinoma.The pathophysiology of NASH is characterized by a deregulation of lipid metabolism that leads to the accumulation of lipids in the hepatocytes. This accumulation of lipids is toxic and one of the causes of insulin resistance and the development of diabetes mellitus. All stages of lipid metabolism are affected by an accumulation of triglycerides, an increase in hepatic lipogenesis and a decrease in ß-oxidation. The composition and the role of lipids as a promoter of NASH is being increasingly studied.The first part of the thesis concerns the detection of diagnostic markers of NASH. In this study, we established for the first time a lipid signature of nonalcoholic steatohepatitis by quantification of 32 lipids. The overall lipid signature allowed distinguishing controls from NAFL and NASH. We have also demonstrated a deregulation of the metabolic pathway involved in the synthesis of fatty acids in NASH. This deregulation has been observed in both humans and animal models in our study.The second part aimed to identify new hepatic prognostic markers of NASH. Microarray analysis of gene expression showed 1549 genes discriminating patients with NAFL or NASH, healthy obese or controls. Among them, 58 genes discriminated NASH from simple steatosis. These genes were involved in extracellular matrix remodeling and inflammation. The most discriminating gene was FABP4 (fatty acid binding protein 4). Among genes strongly associated with high expression of FABP4, matrix metalloproteinase-9 (MMP9) was overexpressed in 55% of NASH patients. We identified a total of 330 differentially regulated genes, of which 229 genes were overexpressed in NASH patients with high levels of MMP9 expression. Using the gene expression levels of the liver FABP4 and MMP9 genes as indicators of disease progression in an independent cohort of NAFLD patients, we identified patients with NAFL and NASH who may have a poor prognosis.Finally, in the third part, we looked at the diagnostic and prognostic value of steatosis of liver grafts, measured by FTIR (Infrared Fourier Transform Microspectroscopy). Indeed, steatosis, when it exceeds 60% and is macrovacuolar, is known to significantly impact the function and survival of liver grafts. In our study, among 58 graft samples, the average percentage of macrovacuolar steatosis and microvesicular steatosis assessed by the pathologist was 2% to 30%, respectively. The average concentration of liver triglycerides measured by gas chromatography-spectrometry was 214 [10-1045] nmol/mg liver tissue. The FTIR triglyceride content estimate was significantly correlated (r2=0.812) with the results of the average hepatic triglyceride concentration measured by gas chromatography-spectrometry. Thirty-four (58%) patients had complications defined by a Dindo-Clavien stage ≥2, including 2 non-primary graft function and 5 deaths. The most discriminating threshold between triglyceride level and TH failure was 59.29 and 54.02 nmol/mg hepatic tissue obtained by spectrometry and FTIR, respectively. Quantification of hepatic triglyceride content by GC/MS was significantly associated with patient survival at the end of follow-up (p <0.0001) and failure of transplantation (p <0.0001). Estimating hepatic triglyceride content using FTIR was significantly associated with one-year post-transplant survival (p <0.0001)

BACKGROUND AND AIMS: Congenital Hepatic Fibrosis (CHF) is caused by mutations in PKHD1, a gene encoding for fibrocystin, a protein of unknown function, expressed in cholangiocyte cilia and centromers. In CHF, biliary dysgenesis is accompanied by severe progressive portal fibrosis and portal hypertension. The mechanisms responsible for portal fibrosis in CHF are unclear. The αvβ6 integrin mediates local activation of TGFβ1 and is expressed by reactive cholangiocytes during cholestasis. To understand the mechanisms of fibrosis in CHF we studied the expression of αvβ6 integrin and its regulation in Pkhd1del4/del4 mice. METHODS: In Pkhd1del4/del4 mice we studied, at different ages (1-12 months): a) portal fibrosis (Sirius Red) and portal hypertension (spleen weight/body weight); b) αvβ6 mRNA and protein expression (RT-PCR, IHC); c) α-SMA and TGFβ1 mRNA expression (RT-PCR); d) portal inflammatory infiltrate (IHC for CD45 and FACS analysis of whole liver infiltrate); f) cytokines secretion from cultured monolayers of primary cholangiocytes (Luminex assay); g) cytokine effects on monocyte/macrophage proliferation (MTS assay) and migration (Boyden chamber); h) TGFβ1 and TNFα effects on β6 integrin mRNA expression by cultured cholangiocytes before and after inhibition of the TGFβ receptor type II (TGFβRII); i) TGFβ1 effects on collagen type I (COLL1) mRNA expression by cultured cholangiocytes. RESULTS: Pkhd1del4/del4 mice showed a progressive increase in αvβ6 integrin expression on biliary cyst epithelia. Expression of αvβ6 correlated with portal fibrosis (r=0.94, p<0.02) and with enrichment of a CD45+ve cell infiltrate in the portal space (r=0.97, p<0.01). Gene expression of TGFβ1 showed a similar age-dependent increase. FACS analysis showed that 50-75% of the CD45+ve cells were macrophages (CD45/CD11b/F4/80+ve). Cultured polarized Pkhd1del4/del4 cholangiocytes secreted from the basolateral side significantly increased amounts of CXCL1 and CXCL10 (p<0.05). Both cytokines were able to stimulate macrophage migration (p<0.05). Basal expression of β6 mRNA by cultured Pkhd1del4/del4 cholangiocytes (0.015±0.002 2^-dCt) was potently stimulated by the macrophage-derived cytokines TGFβ1 (0.017±0.002 2^-dCt, p<0.05) and TNFα (0.018±0.003 2^-dCt, p<0.05). Inhibition of TGFβRII completely blunted TGFβ1 (0.014±0.003 2^-dCt, p<0.05) but not TNFα effects (0.017±0.001 2^-dCt, p=ns) on β6 mRNA. COLL1 mRNA expression by cultured Pkhd1del4/del4 cholangiocytes (0.0009±0.0003 2^-dCt) was further and significantly increased after TGFβ1 stimulation (0.002±0.0005 2^-dCt, p<0.05). CONCLUSIONS: Pkhd1del4/del4 cholangiocytes possess increased basolateral secretory functions of chemokines (CXCL1, CXCL10) able to orchestrate macrophage homing to the peribiliary microenvironment. In turn, by releasing TGFβ1 and TNFα, macrophages up-regulate αvβ6 integrin in Pkhd1del4/del4 cholangiocytes. αvβ6 integrin activates latent TGFβ1, further increasing the fibrogenic properties of cholangiocytes.