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Littérature scientifique sur le sujet « Spexine »

Auteur : Grafiati

Publié le 11 janvier 2025

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Articles de revues sur le sujet "Spexine"

Lv, Shuangyu, Yuchen Zhou, Yu Feng, Xiaomei Zhang, Xinyue Wang, Yanjie Yang et Xinchun Wang. « Peripheral Spexin Inhibited Food Intake in Mice ». International Journal of Endocrinology 2020 (5 août 2020) : 1–9. http://dx.doi.org/10.1155/2020/4913785.

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Spexin (SPX, NPQ), a novel endogenous neuropeptide, was firstly identified by bioinformatics. Spexin gene and protein widely distributed in the central nervous system and peripheral tissues, such as the hypothalamus and digestive tract. The role of spexin in appetite regulation in mammalian is still unclear. The present study was designed to investigate the mechanism and effect of peripheral spexin on food intake in mice. During the light period, an intraperitoneal (i.p.) injection of spexin (10 nmol/mouse) significantly inhibited cumulative food intake at 2, 4, and 6 h after treatment in fasted mice. During the dark period, spexin (1 and 10 nmol/mouse, i.p.) significantly suppressed cumulative food intake at 4 and 6 h after treatment in freely feeding mice. The GALR3 antagonist SNAP37889, not GALR2 antagonist, significantly antagonized the inhibitory effect on cumulative food intake (0–6 h) induced by spexin. Spexin significantly reduced the mRNA level of Npy mRNA, not Agrp, Pomc, Cart, Crh, Orexin, or Mch, in the hypothalamus. Spexin (10 nmol/mouse, i.p.) increased the number of c-Fos positive neurons in hypothalamic AHA and SCN, but not in ARC, DMN, LHA, PVN, SON, or VMH. The hypothalamic p-CaMK2 protein expression was upregulated by spexin. This study indicated that acute peripheral injection of spexin inhibited mouse food intake. The anorectic effect may be mediated by GALR3, and inhibiting neuropeptide Y (NPY) via p-CaMK2 and c-Fos in the hypothalamus.

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Liu, Ying, Di Wu, Hangping Zheng, Yunzhi Ni, Lu Zhu, Yaojing Jiang, Jiarong Dai et al. « Serum Spexin Level Is Negatively Associated With Peripheral Neuropathy and Sensory Pain in Type 2 Diabetes ». Journal of Diabetes Research 2024 (23 mai 2024) : 1–12. http://dx.doi.org/10.1155/2024/4538199.

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Background: Spexin is a novel peptide hormone and has shown antinociceptive effects in experimental mice. This study is aimed at evaluating the association of serum spexin level with diabetic peripheral neuropathy (DPN) and related pain in a Chinese population.Methods: We enrolled 167 type 2 diabetes mellitus (T2DM) including 56 patients without DPN (non-DPN), 67 painless DPN, and 44 painful DPN. Serum spexin was measured using ELISA. Logistic regression models were performed to analyze the independent effects of spexin on prevalence of DPN and painful DPN. In streptozotocin (STZ)-induced diabetic mice, mechanical pain threshold was measured using electronic von Frey aesthesiometer. Human peripheral blood mononuclear cells (PBMCs) were isolated and further stimulated with lipopolysaccharide without or with spexin. The gene expression was assayed by qPCR.Results: Compared with non-DPN, serum spexin level decreased in painless DPN and further decreased in painful DPN. The odds of DPN was associated with low spexin level in T2DM, which was similar by age, sex, BMI, and diabetes duration, but attenuated in smokers. The odds of having pain was associated with decreased spexin level in DPN, which was similar by age, sex, smoking status, and diabetes duration, but attenuated in normal weight. Furthermore, we observed that mechanical pain threshold increased in spexin-treated diabetic mice. We also found that lipopolysaccharide treatment increased the mRNA level of TNF-α, IL-6, and MCP-1 in human PBMCs, while spexin treatment prevented this increase.Conclusions: These results suggested that spexin might serve as a protective factor for diabetes against neuropathology and pain-related pathogenesis.

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Karaca, Anara, Filiz Bakar-Ates et Nese Ersoz-Gulcelik. « Decreased Spexin Levels in Patients with Type 1 and Type 2 Diabetes ». Medical Principles and Practice 27, n^o 6 (2018) : 549–54. http://dx.doi.org/10.1159/000493482.

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Background/Aims: Spexin is a novel peptide which has a potential role as a biomarker of insulin resistance, diabetes, and obesity. Our aim was to measure spexin levels in lean type 1 diabetic patients and its relevance to glycemic parameters without the presence of obesity or insulin resistance. Subjects and Methods: This cross-sectional study included 29 type 1 and 30 type 2 diabetic patients and a control group of 23 healthy subjects with adjusted age, sex, and body mass index (BMI). Height and weight were measured using standard techniques. Glucose levels, triglycerides, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, serum cortisol levels, and spexin levels were measured in each patient. Results: The median fasting serum spexin levels were significantly lower in patients with type 1 and type 2 diabetes than in control subjects (p = 0.008 and p = 0.041, respectively). Spexin levels were not correlated with glycemic parameters, lipids, BMI, cortisol levels, and thyroid-stimulating hormone (p > 0.05). Only age turned out to be correlated with spexin levels in patients with type 1 diabetes when we analyzed the groups separately. Regression models, including age and diabetes duration, revealed no association between age and spexin levels. Regression models, including cortisol, BMI, and HbA1c, revealed no association with spexin levels within each group. Conclusion: The presence of type 1 diabetes is associated with lower spexin levels, independent of glucose, lipid parameters, and BMI. The expression of spexin in the pancreas apart from the current glycemic control of the patients may be the main determinant of spexin levels in type 1 diabetic patients.

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F. salih, Ruaa, Hala Abd Al-Qadir Al-Moayad Abd Al-Qadir Al-Moayad, Firas abbas, Jalil I. Alezzi et Asrar Saleh Mohammed. « Association of Spexin Hormone Levels with Metabolic Disturbance in Women with Polycystic Ovarian Syndrome ». Diyala Journal of Medicine 27, n^o 1 (25 octobre 2024) : 12–24. http://dx.doi.org/10.26505/djm.v27i1.1138.

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Background: Polycystic ovarian syndrome is affecting around 5–15% of females. Spexin hormone, identified as neuropeptide Q, has been newly recognized by bioinformatics methods. Objective: To evaluate the relationship concerning levels of spexin hormone with metabolic disruption in women with polycystic ovarian syndrome. Patients and Methods: A case-control study carried out in the department of Obstetrics and Gynecology in Al-Imamain Al-Khademain medical city/Baghdad, Iraq, from Jan 1, 2022, to the end of Dec 31, 2022. The study sample comprises, 192 participants aged 18-45 years were joined and allocated into a case group (96 women with PCOS) and a control group (96 women without PCOS). Results: Mean value of spexin hormone was (2.7±0.3 ng/mL) in the PCOS group, while it was (3.5±0.7 ng/mL) in the control group; fasting blood sugar shows significant association with a negative, weak correlation with Spexin in patients (P-value= 0.005), Insulin shows significant association with inverse correlation with Spexin in patients (P-value= 0.04), Homeostasis model valuation of insulin resistance (HOMA-IR) shows significant association with inverse correlation with Spexin in patients (P-value= 0.003). Spexin had a significant inverse correlation with LH, SHBG, testosterone, FAI, and Dehydroepiandrosterone. Conclusion: Serum level of spexin hormone was meaningfully decreased in patients with PCOS than that in healthy women. Keywords: Polycystic ovary syndrome, Spexin, Hormonal, Metabolic Disturbance.

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Bacopoulou, Flora, Despoina Apostolaki, Aimilia Mantzou, Artemis Doulgeraki, Artur Pałasz, Pantelis Tsimaris, Eleni Koniari et Vasiliki Efthymiou. « Serum Spexin is Correlated with Lipoprotein(a) and Androgens in Female Adolescents ». Journal of Clinical Medicine 8, n^o 12 (2 décembre 2019) : 2103. http://dx.doi.org/10.3390/jcm8122103.

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The Spexin gene is considered the most dysregulated in obese human fat. Limited data suggest that the novel peptide spexin may potentially impact food intake, weight regulation and body adiposity. The aim of this case-control study was to compare fasting serum spexin concentrations between normal weight (NW) and overweight/obese (OB/OW) adolescent females and explore the relationship between circulating spexin and anthropometric, bone and fat mass, metabolic and hormonal parameters. Eighty post-menarcheal females (mean age ± SD 16.23 ± 2.26 years); 55 NW (mean BMI ± SD 19.72 ± 2.52 kg/m2) and 25 OB/OW (mean BMI ± SD 29.35 ± 3.89 kg/m2) participated in the study. Circulating spexin levels did not differ significantly (p = 0.378) between NW (median (interquartile range), 0.26 (0.17) ng/mL) and OB/OW (median (interquartile range), 0.28 (0.06) ng/mL) adolescents and did not correlate with BMI (rs = −0.090, p = 0.438), % body fat (rs = −0.173, p = 0.409), glucose or insulin resistance indices derived from fasting and oral glucose tolerance states. In the total study sample, spexin concentrations correlated positively with lipoprotein(a) (rs = 0.402, p = 0.046). In the OB/OW adolescents spexin levels correlated positively with testosterone (rs = 0.727, p = 0.011) and free androgen index (rs = 0.755, p = 0.007). In the NW adolescents, spexin concentrations correlated negatively with dehydroepiandrosterone sulphate (rs = −0.445, p = 0.038). Results may suggest potential involvement of spexin in the regulation of lipoprotein(a) and of the reproductive/adrenal axis in post-menarcheal adolescent females.

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Ozturk Onsal, Fatma Duygu, Ahmet Ucar, Ali Bulbul, Zeynep Yildiz Yildirmak et Gizem Kara Elitok. « Associations of Size at Birth and Metabolic Syndrome Antecedents With Serum Spexin Levels in Prepubertal Children ». Journal of the Endocrine Society 5, Supplement_1 (1 mai 2021) : A709—A710. http://dx.doi.org/10.1210/jendso/bvab048.1445.

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Abstract Background: Spexin is a novel peptide implicated in food intake and obesity. The primary aim of this study was to analyze whether serum spexin levels, along with total leptin and active ghrelin levels were different in prepubertal children born small for gestational age(SGA) and appropriate for gestational(AGA). Secondary aims were to analyze whether serum spexin, leptin and active ghrelin levels correlated with metabolic syndrome(MS)antecedents according to the Dietary and lifestyle-induced health effects in children and infants (IDEFICS)study. Subjects and Methods: We conducted a cross-sectional study on prepubertal37SGA- (median:5.6yr)and50prepubertalAGA-born children(median:5.9yr). Anthropometric data, homeostasis model assessment of insulin resistance(HOMAIR),plasma lipids, serum spexin, total leptin and active ghrelin levels were analyzed. Associations of serum spexin levels with MS antecedents according to the IDEFICS study were investigated. Results: Children bornSGA had higher body mass index and waist circumference than AGA-born peers(p <0.05). Serum total leptin levels were higher in SGA-born children than in AGA-born peers (p<0.05). Plasma active ghrelin and spexin levels were not different between the subgroups(p>0.05). Children bornSGA had higher MS risk scores than AGA-born peers(p <0.05). Small for gestational age- born children had higher plasma glucose,insulin and HOMA-IR than AGA-born peers(p<0.05). In children born SGA, the number of subjects with excess adiposity (NSGA=18(43.9%)andNAGA=7(14%),p=0.016)and insulin resistance(NSGA=14(34%) andNAGA=6(12%),p=0.035)was higher than in AGA-born peers. There was no significant difference in frequency of dyslipidemia between the subgroups(p=0.19). The frequency of children with more than one MS antecedent was higher in SGA-born children than in AGA-born peers(Chi-Square p <0.01). Metabolic syndrome risk score according to IDEFICS was higher in SGA born children than in AGA-born peers(2.2±1.8vs1.1±1.8;p=0.008). Serum spexin levels were lower in children with MS antecedents than those without MS antecedents in both AGA -and SGA-born children[Serum spexin levels in AGA-born children with and without MS antecedents: 48,5pg/mL(25-75%IQR:19.8-93.8pg/mL)and143pg/mL(25-75%IQR:104-211pg/mL),p<0.001;respectively, serum spexin levels inSGAborn children with and without MS antecedents: 31,0pg/mL(25-75%IQR:16.5-47.0 pg/mL) and79.5pg/mL(25-75% IQR:49.5-274.8pg/mL),p=0,0016;respectively]. In the whole study group, the most important factor associated with excess adiposity was history of being born SGA(OddsRatio=91.3[95%CI:2.2-374;p=0.017] Conclusions: Serum spexin levels were not different inSGA- and AGA-born children. Serum spexin levels were reduced in children with MS antecedents independent of size at birth.

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Cichoń, Lena, Artur Pałasz, Krzysztof M. Wilczyński, Aleksandra Suszka-Świtek, Anna Żmijowska, Ireneusz Jelonek et Małgorzata Janas-Kozik. « Evaluation of Peripheral Blood Concentrations of Phoenixin, Spexin, Nesfatin-1 and Kisspeptin as Potential Biomarkers of Bipolar Disorder in the Pediatric Population ». Biomedicines 12, n^o 1 (29 décembre 2023) : 84. http://dx.doi.org/10.3390/biomedicines12010084.

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There are some initial suggestions in the literature that phoenixin, spexin, nesfatin-1 and kisspeptin may play a role in the pathogenesis of affective disorders. Therefore, they may also be cautiously considered as potential diagnostic or predictive biomarkers of BD. This study aimed to evaluate the levels of the aforementioned neuropeptides in the peripheral blood of children and adolescents with bipolar. This study included 122 individuals: 67 persons with diagnosed bipolar disorder types I and II constituted the study group, and 55 healthy persons were included in the control group. Statistically significant differences in the concentrations of neuropeptides between the control and study groups were noted in relation to nesfatin-1 and spexin (although spexin lost statistical significance after introducing the Bonferroni correction). In a logistic regression analysis, an increased risk of bipolar disorder was noted for a decrease in nesfatin-1 concentration. Lower levels of nesfatin-1 seemed to be a significant risk factor for the development of bipolar disorder types I and II. Furthermore, the occurrence of bipolar disorder was associated with significantly elevated levels of spexin. None of the analyzed neuropeptides was significantly correlated with the number of symptoms of bipolar disorder.

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Yazgan, Burak, Filiz Avcı, Gülsün Memi et Ebru Tastekin. « Inflammatory response and matrix metalloproteinases in chronic kidney failure : Modulation by adropin and spexin ». Experimental Biology and Medicine 246, n^o 17 (22 mai 2021) : 1917–27. http://dx.doi.org/10.1177/15353702211012417.

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Chronic kidney disease is a major global public health problem. The peptide hormones adropin and spexin modulate many physiological functions such as energy balance and glucose, lipid and protein metabolism. However, it is unclear whether these peptides may exert effects on renal damage, tissue remodeling, and inflammatory conditions. In view of the limited information, we aimed to investigate the effect of adropin and spexin on matrix metalloproteinase and inflammatory response genes a rat model of adenine-induced chronic kidney failure. Chronic kidney failure was induced in rats by administering adenine hemisulfate. Renal function was determined in an autoanalyzer. Histopathological modifications were assessed by H&E staining. mRNA expression levels of ALOX 15, COX 1, COX 2, IL-1β, IL-10, IL-17A, IL-18 IL-21, IL-33, KIM-1, MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, MMP-13, NGAL, TGFβ1, TIMP-1, and TNFα in kidney tissue were measured by qPCR. Our results showed an increase of 24-h urine volume, serum creatinine, BUN, and urine protein levels in group with adenine-induced CKF. Adropin and spexin treatments decreased urine protein and 24-h urine volume. Renal damage, TIMP-1, IL-33, and MMP-2 increased after CKF induction, while COX 1, MMP-9, and MMP-13 levels were significantly reduced. Furthermore, KIM-1, TIMP-1, IL-33, and MMP-2 were downregulated by spexin treatment. Renal damage, NGAL, TIMP-1 IL-17A, IL-33, MMP-2, and MMP-3 decreased after adropin treatment, while MMP-13 levels were upregulated. Treatment with adropin+spexin decreased KIM-1, NGAL, TIMP-1, IL-1β, IL-17A, IL-18, IL-33, ALOX 15, COX 1, COX 2, TGFβ1, TNFα, MMP-2, MMP-3, and MMP-7, but increased MMP-13 levels. Our findings revealed that inflammatory response and MMP genes were modulated by adropin and spexin. These peptides may have protective effects on inflammation and chronic kidney damage progression.

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Ghannawi,, L. A., K. Gharab,, M. A. Hadi,, O. Y. Shakir, et A. M. Rahmah. « Spexin level in growth hormone deficiency Iraqi children ». Ukrainian Biochemical Journal 96, n^o 4 (3 septembre 2024) : 55–61. http://dx.doi.org/10.15407/ubj96.04.055.

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Spexin (SPX) is a newly discovered brain adipokine implicated in various homeostatic functions including metabolism, energy balance, endocrine processes and growth hormone (GH) production in particular. At the same time, the growth-promoting effects of GH are influenced by Insulin-like growth factor-1 (IGF‑1) and vitamin D3. The aim of this study was to investigate the possible involvement of SPX in growth hormone deficiency (GHD) in children. The research involved 90 children (40 with growth hormone deficiency and 50 healthy controls aged 5-14). Serum levels of GH, IGF and vitamin D3 were tested using a chemiluminescent immunoassay, that of SPX – by Elabscience ELISA Kit. The results revealed that children with GHD had significantly higher SPX levels compared to the control group. No significant difference in IGF-1 and vitamin D3 levels between patients and control groups was observed. In the GHD group, we found a significant negative correlation between SPX and GH levels; at the same time, there was no correlation between SPX and D3 levels. These findings suggest that the changes in SPX levels may contribute to growth hormone deficiency. Keywords: growth hormone deficiency, IGf-1, Iraqi children, spexin, vitamin D3

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Abdualhay, Raghda Abdulsamad, et Adnan Jassim Mohammed Al-Fartosy. « Insulin Resistance and Other Adipokines as Clinical Predictors of Gestational Diabetes Mellitus among Pregnant Women ». Indonesian Biomedical Journal 14, n^o 3 (8 septembre 2022) : 243–51. http://dx.doi.org/10.18585/inabj.v14i3.1934.

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BACKGROUND: Gestational diabetes mellitus (GDM) has a strong relationship with an increased risk of maternal and perinatal complications. However, in Basrah, Iraq, studies regarding GDM are still limited. In current study, we aimed to investigate the association between insulin resistance and some clinical predictors of GDM among pregnant women in 1st and 3rd trimesters of gestation.METHODS: This case-control study was conducted on 44 pregnant women with GDM and 45 without GDM aged 20 to 40 years who applied for GDM screening during the first (9-13 week) and third trimester (24-28 week) of pregnancy. Demographics, blood glucose, HbA1c, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), spexin, nesfatin-1, orexin-A, vaspin and lipid profile levels were compared between groups.RESULTS: Subjects with GDM showed a higher level of glucose, insulin HOMA-IR, HbA1c, spexin, vaspin in the first and third trimesters of pregnancy (p<0.01) compared to the healthy subjects. Meanwhile in the first and third trimester, subjects with GDM showed significantly lower level of nesfatin-1 and orexin-A compare to the control. In third trimester, oral glucose tolerance test (OGTT) outcomes for fasting glucose at 1 hour, 2 hours, and 3 hours after glucose load were significantly higher (p<0.01). According to the area under the receiver operating characteristics (ROC) curve (AUC) findings, HOMA-IR, spexin, and vaspin may be more effective predictors biomarkers for GDM in pregnant subjects, while orexin-A and nesfatin-1 were ineffective.CONCLUSION: The correlation of insulin resistance and adipokines in the first and thrid trimester was not significantly different, which may cast new light on the possible role as an etiological cause of GDM and might be a better monitoring parameter in women with GDM. KEYWORDS: gestational diabetes mellitus, insulin resistance, vaspin, spexin, orexin-A, nesfatin-1

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Thèses sur le sujet "Spexine"

Berthomé, Yann. « Conception, synthèse et évaluation de nouveaux peptides fluorocarbonés dérivés de la spexine pour le traitement de la douleur ». Electronic Thesis or Diss., Strasbourg, 2024. http://www.theses.fr/2024STRAF036.

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La douleur chronique est un problème de santé publique majeur, qui a un impact considérable sur la société. Malgré de nombreuses avancées dans le domaine les opioïdes sont toujours utilisés comme substances analgésiques de référence, en dépit des nombreux effets secondaires qu’ils véhiculent (tolérance, addiction). Il est donc urgent d’identifier de nouvelles cibles et médicaments pour le traitement de la douleur. Au cours de cette thèse, notre intérêt s’est porté sur le récepteur GALR2 et son agoniste endogène la spexine qui sont impliqués dans des voies de modulations non-opioïdes de la douleur. Afin d’améliorer les propriétés biologiques de la spexine, et notamment sa stabilité métabolique, des dérivés fluorocarbonés ont été synthétisés et caractérisés in vitro. Une étude des relations structure-activité a permis d’identifier un composé prometteur qui a été utilisé pour étudier la douleur dans un modèle murin de douleur inflammatoire. Afin de comprendre les phénomènes régissant les propriétés biophysiques et biochimiques intéressantes de ce nouveau composé, diverses sondes fluorescentes dérivés de la spexine ont été synthétisés. Ces outils ont permis la mise en place de plusieurs essais in vitro avec pour résultats l’identification des mécanismes clefs régissant l’augmentation d’activité fonctionnelle et de stabilité métabolique des composés
Chronic pain is a major public health issue, with a huge impact on society. Despite numerous advances in the field, opioids still represent the gold-standard analgesics, despite their noxious side effects (tolerance, addiction). Therefore, there is an urgent need to identify new targets and drugs for the treatment of pain. In this thesis, we focused on the GALR2 receptor and its endogenous agonist spexin, which are involved in non-opioid pain modulation pathways. To improve spexin's biological properties, and in particular its metabolic stability, fluorocarbon derivatives were synthesized and characterized in vitro. A study of structure-activity relationships led to the identification of a promising compound, which has been used to study pain in vivo. To investigate the particularly interesting biophysical and biochemical properties of this new compound, various fluorescent probes derived from spexin were designed and synthesized. These tools were used to implement several in vitro assays, resulting in the identification of key mechanisms leading to the increase of the functional activity and the metabolic stability of fluorospexins

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Sarasin, Gloria. « Analisi dell'espressione di spexina e augurina in tessuti di ratto ». Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3427469.

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Wong, Ka-hei, et 黃家禧. « Novel function of spexin as a satiety factor in feeding control ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/207994.

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Spexin (SPX), also called neuropeptide Q (NPQ), is a novel neuropeptide discovered recently using the bioinformatic approach. Except for mammals, SPX has not been reported in lower vertebrates including fish and amphibians. Following its discovery, the biological functions of this peptide in both higher and lower vertebrates are still largely unknown. To examine the structure and functions of SPX in fish model, molecular cloning of goldfish SPX has been performed and found to be highly comparable to its mammalian counterparts. In goldfish, broad expression of SPX transcripts has been found in various tissues. In vivo feeding studies have revealed that SPX mRNA levels in the telencephalon, optic tectum and hypothalamus of goldfish brain could be elevated by food intake. Brain injection of goldfish SPX, however, inhibited both basal and NPY- and orexin-induced feeding behaviour and food consumption. Similar treatment has also reduced transcript expression of NPY, AGRP and apelin with concurrent rises in CCK, CART, POMC, MCH and CRH mRNA levels in different brain areas examined. The differential effects of goldfish SPX on NPY, CCK and MCH transcript expression could also be noted in vitro in goldfish brain cell culture. In mice, SPX has been also found to be expressed within the brain-gut axis, including the stomach and specific neuronal subpopulations within the hypothalamus, including the ARC, PVN, DMN, and VMN. Similar to goldfish, feeding has shown to affect SPX mRNA and protein expression. Fasted animals have lower SPX mRNA in the stomach, and lower SPX protein levels in the serum and glandular stomach; the opposite effects have been noted in ad libitumfed animals. Both IP and ICV injection of SPX could produce a short-term feeding inhibitory effect. Furthermore, ICV administration of SPX could also downregulate hypothalamic expression of NPY, NPY5R, AGRP, and GHSR mRNA, and upregulate leptin receptor and MC4R gene expression concurrently. Taken together, these findings suggests that SPX may act as a satiety factor in vertebrate species. Apparently, SPX expression could be induced by feeding and the neuropeptide could act centrally to inhibit feeding by differentially regulating orexigenic and anorexigenic signals within the CNS.
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Sherman, Shermel B. « The Role of Neuropeptide Spexin in the Modulation of Metabolism and Behaviors ». University of Toledo Health Science Campus / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=mco1596840064046446.

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Huang, Tao. « Toward novel therapeutics for functional constipation : from traditional Chinese medicine herbal formula MaZiRenWan to cyclic spexin analogues ». HKBU Institutional Repository, 2017. https://repository.hkbu.edu.hk/etd_oa/388.

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Functional constipation (FC) is a major gastrointestional (GI) disorder which affects about 14% population worldwide. However, due to efficacy and safety concerns, more than 50% FC patients are not completely satisfied with current conventional therapies, thus alternative therapies are needed. A substantial part of FC patients have symptom of slow colonic motility, while therapy targeting a single pathway cannot benefit all of them. In this thesis, we searched for novel FC therapeutics from two distinct sources, both of which can improve colonic motility significantly: (1) MaZiRenWan (MZRW), an herb formula from Traditional Chinese Medicine (TCM); and (2) Spexin (SPX), a newly identified neuropeptide that is deregulated in FC. On the basis of efficacy validation for MZRW by randomized, placebo-controlled clinical studies, we investigated the bioactive compounds and pharmacological actions of MZRW. Firstly, a machine-learning based method, namely MOST, was developed to relate bioactive compounds with their mechanism-of-action targets. MOST demonstrated good performance in 7-fold cross-validation (over 87% accuracy) and temporal validation (over 76% accuracy). In the case laxative effect, MOST predicted that acetylcholinesterase (ACHE) was the mechanism-of-action target of aloe-emodin; in vivo studies validated this prediction. Secondly, we analyzed the bioactive compounds and mechanism-of-actions of MZRW with combination of UPLC-QTOF-MS/MS, clustering analysis, organ bath, and MOST approaches. 97 compounds were identified in MZRW extract, and 35 of them can be found in plasma and feces samples of rats with oral administration of MZRW. Chemical space analysis suggested that these compounds can be classified into component groups, while the corresponding pharmacology can be studied with representative compounds. Emodin, amygdalin, albiflorin, honokiol, and naringin were shown to induce spontaneous contractions of rat colonic smooth muscle in vitro. Biological targets in ACh-, estrogen-, prostaglandin-, cannabinoid-, and purine signaling pathways are able to explain the prokinetic effects of representative compounds and component groups. Pharmacological actions of MZRW are mixture of five classic paradigms. Thirdly, the latest results of three-armed, randomized and controlled clinical study showed that MZRW demonstrated comparable efficacy with the first line drug Senna, the first line drug for constipation in HK, during treatment period, both were better than placebo; and the efficacy was more sustainable in follow-up period when comparing that of Senna and placebo. These data suggested the unique pharmacological profile of MZRW for FC. With pharmacometabolomic analysis, we found that change of oleamide is negatively correlated (pearson r = -0.59, p<0.001) with improvement of Complete Spontaneous Bowel Movement (CSBM) in MZRW group, but not in Senna or placebo group. Oleamide is up-regulated in FC patients compared with healthy controls, and MZRW can significantly reduce oleamide in FC patients (n=30), healthy human volunteers (n=23), and in normal mice (n=12) serum, ileum, and colon. The regulation of oleamide by MZRW is possibly via augmenting FAAH-mediated degradation. Lastly, we investigated the possibility to use SPX, the newly identified, FC-associated neuropeptide to change GI motility. The deregulation of SPX has been found in several disorders including FC, however, the metabolic instability of SPX prevent it to be directly used in clinical practices. Our investigation through combination of molecular dynamics (MD) simulations and NMR analysis suggested a β-turn-helix-β-turn (βαβ) conformation for human spexin (hSPX) adopts in solution. Consistent with this conformation, cyclic analogues of hSPX with a disulfide bond between residue 1 and 13, LH101 (CWTPQAMLYLKGCQ-NH2), activated both GalR2 (EC50=1.19 μM) and GalR3 (EC50=1.56 μM) with potency comparable to wild type, and that the acetylation at the N-terminal, LH101(Ac) raises the potency EC50=0.38 μM on GalR2 and EC50=0.39 μM on GalR3. The serum half lives of LH101 (t1/2=355.7 min) and LH101(Ac) (t1/2=1973.7 min) were significantly longer than the wild type (t1/2=66.5 min), and LH101(Ac) induces the contractions of mice intestinal segment in vitro and attenuates the oleamide-induced slow GI motility in vivo. Collectively, our studies in MZRW suggested that estrogen and oleamide signaling pathways are potential new targets to develop novel therapeutics for FC, while lead compounds targeting these pathways could be found from MZRW. The final study suggested CSAs have potential to be developed as new FC therapy by targeting the galanin receptor associated pathway.

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Chapitres de livres sur le sujet "Spexine"

Porzionato, Andrea, Marcin Rucinski, Veronica Macchi, Carla Stecco, Gloria Sarasin, Maria M. Sfriso, Camillo Di Giulio, Ludwik K. Malendowicz et Raffaele De Caro. « Spexin Is Expressed in the Carotid Body and Is Upregulated by Postnatal Hyperoxia Exposure ». Dans Advances in Experimental Medicine and Biology, 207–13. Dordrecht : Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-4584-1_29.

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Actes de conférences sur le sujet "Spexine"

Arko, Matej, Jochen Campo, Marijn Siemons, Robbert Winkelman, Alexander Eigenraam, Paul Tol, Mario Vretenar et al. « Calibration campaign of SPEXone Second Generation : early results and instrument performance ». Dans Sensors, Systems, and Next-Generation Satellites XXVIII, sous la direction de Toshiyoshi Kimura, Sachidananda R. Babu et Arnaud Hélière, 11. SPIE, 2024. http://dx.doi.org/10.1117/12.3031658.

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van der Schaaf, Laura, Marissa Jonker, Raul Laasner, Jeroen H. H. Rietjens, Otto P. Hasekamp, Mario Vretenar, Paul Tol et Martijn Smit. « Georegistration and viewport coregistration for SPEXone, the multi-angle spectropolarimeter on-board the NASA PACE satellite ». Dans Sensors, Systems, and Next-Generation Satellites XXVIII, sous la direction de Toshiyoshi Kimura, Sachidananda R. Babu et Arnaud Hélière, 12. SPIE, 2024. http://dx.doi.org/10.1117/12.3031741.

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van Amerongen, Aaldert, Jeroen Rietjens, Jochen Campo, Ersin Dogan, Jos Dingjan, Raj Nalla, Jerome Caron et Otto Hasekamp. « SPEXone : a compact multi-angle polarimeter ». Dans International Conference on Space Optics - ICSO 2018, sous la direction de Nikos Karafolas, Zoran Sodnik et Bruno Cugny. SPIE, 2019. http://dx.doi.org/10.1117/12.2535940.

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Hoogeveen, Ruud, Ralf Kohlhaas, Jochen Campo, Jeroen Rietjens, Alexander Eigenraam, Ian Veenendaal, Marijn Siemons et al. « SPEXone, the multi-angle spectropolarimeter for PACE, adjusted and improved for new space applications ». Dans International Conference on Space Optics — ICSO 2022, sous la direction de Kyriaki Minoglou, Nikos Karafolas et Bruno Cugny. SPIE, 2023. http://dx.doi.org/10.1117/12.2690835.

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Rietjens, Jeroen, Martijn Smit, Jochen Campo, Thomas Bouchan, Ryan Cooney, Pierre Piron, Paul Tol et al. « SPEXone multi-angle spectropolarimeter characterization, calibration, and key data derivation using the L0-1B processor ». Dans International Conference on Space Optics — ICSO 2022, sous la direction de Kyriaki Minoglou, Nikos Karafolas et Bruno Cugny. SPIE, 2023. http://dx.doi.org/10.1117/12.2690892.

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Rietjens, Jeroen, Jochen Campo, Martijn Smit, Robbert Winkelman, Raj Nalla, Jochen Landgraf, Otto Hasekamp, Marc Oort et Aaldert van Amerongen. « Optical and system performance of SPEXone, a multi-angle channeled spectropolarimeter for the NASA PACE mission ». Dans International Conference on Space Optics — ICSO 2021, sous la direction de Zoran Sodnik, Bruno Cugny et Nikos Karafolas. SPIE, 2021. http://dx.doi.org/10.1117/12.2599531.

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Campo, Jochen, Paul Tol, Joris van der Vlugt, Martijn Smit, Jelle Talsma, Jens Johansen, Alexander Eigenraam et al. « Characterization and video chain development of the CMOS detector applied in the multi-angle spectro-polarimeter SPEXone ». Dans International Conference on Space Optics — ICSO 2021, sous la direction de Zoran Sodnik, Bruno Cugny et Nikos Karafolas. SPIE, 2021. http://dx.doi.org/10.1117/12.2599224.

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Rietjens, Jeroen H. H., Jochen Campo, Anantha Chanumolu, Martijn Smit, Raj Nalla, Cristina V. Fernandez, Jos Dingjan, Aaldert van Amerongen et Otto P. Hasekamp. « Expected performance and error analysis for SPEXone, a multi-angle channeled spectropolarimeter for the NASA PACE mission ». Dans Polarization Science and Remote Sensing IX, sous la direction de Frans Snik, Julia M. Craven et Joseph A. Shaw. SPIE, 2019. http://dx.doi.org/10.1117/12.2530729.

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Campo, Jochen, Marijn Siemons, Matej Arko, Paul Tol, Jeroen Rietjens, Laura van der Schaaf, Martijn Smit et al. « Detector characterization and upcoming instrument calibration of an improved version of the five-angle spectro-polarimeter SPEXone ». Dans Sensors, Systems, and Next-Generation Satellites XXVII, sous la direction de Toshiyoshi Kimura, Sachidananda R. Babu et Arnaud Hélière. SPIE, 2023. http://dx.doi.org/10.1117/12.2684431.

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Al-fatlawiy, Hussein Dhahir Ayyez, Hanaa Addai Ali et Ali Fattah Naser. « Evaluation of serum spexin level which is associated with insulin resistance and beta- cellfunction in Iraq patients with type II diabetes mellitus ». Dans 3RD INTERNATIONAL SCIENTIFIC CONFERENCE OF ALKAFEEL UNIVERSITY (ISCKU 2021). AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0067499.

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