Melanocortin-4 receptor regulation of reproductive function in black rockfish (Sebastes schlegelii).

Melanocortin-4 receptor (MC4R) is a G protein-coupled receptor with multiple functions in mammals. However, the functions of MC4R in fish have not been investigated extensively. The purpose of this study was to determine potential regulation of reproduction by the MC4R. We cloned the black rockfish MC4R and analyzed its tissue distribution and function. The results showed that black rockfish mc4r cDNA consisted of 981 nucleotides encoding a protein of 326 amino acids. The quantitative PCR data showed that mc4r mRNA was primarily expressed in the brain, gonad, stomach and intestine. In the brain, mc4r was found to be primarily located in the hypothalamus. Both α-MSH and ß-MSH increased gnih expression and decreased sgnrh and cgnrh expression (P < 0.05). α-MSH and ß-MSH had opposite effects on kisspeptin expression. In contrast, α-MSH and ß-MSH increased the expression of cyp11, cyp19, 3ß-hsd and star. In summary, our study shows that MC4R in black rockfish might regulate reproductive function and that the effects of α-MSH and ß-MSH might differ.

Regulation of pure total flavonoids from Citrus on TH17/Treg balance in mice with NASH.

This study aimed to investigate the involved immunologic mechanism of pure total flavonoids from Citrus (PTFC) on the development of non-alcoholic steatohepatitis (NASH). C57BL/6 mice were fed with high .fat diet for 16 weeks to induce the NASH model, and from the 7th week three dosages (25, 50 and 100 mg x kg(-1) x d(-1)) of PTFC were administrated intragastric for 10 weeks respectively. Serum TG, CHOL, ALT, AST were determined by biochemical assay, histopathological changes of the liver tissue were observed by HE staining, expression of RORyt and Foxp3 mRNA of the liver tissue was detected by Real-time PCR, and serum IL-17, IL-6, IL-10 and IL-4 were determined by.Cytometric Beads Array. As a result, we find that after the administration of PTFC, the in- flammation of the liver tissue of NASH mice was attenuated, liver function was improved, and the expression of RORgammat mRNA was higher in the liver tissue while which was lower of Foxp3 mRNA, the level of proinflammatory cytokines IL-17 and IL-6 decreased and the level of suppressive cytokines IL-10 and IL-4 increased. These data show that PTFC protects the development of NASH through regulating the Th17/Treg balance and attenuating inflammation.

[Effect of pure total flavonoids from citrus on hepatic SIRT1/PGC-1alpha pathway in mice with NASH].

OBJECTIVE: To observe the effect of pure total flavonoids from Citrus (PTFC) on the hepatic fatty degeneration, inflammation, oxidative stress and SIRT1/PGC-1alpha expressions in mice with non-alcohol steatohepatitis (NASH), and discuss the action mechanism of PTFC on NASH. METHOD: Mice were given high-fat diet for 16 weeks to induce the NASH model. Since the seventh week after the model establishment, the mice were intervened with 100, 50 and 25 mg x kg(-1) x d(-1) PTFC for 10 weeks. The pathologic changes in hepatic tissues were observed with HE staining. The contents of TG, CHOL in hepatic tissue, as well as the levels of AST, ALT in serum were detected by using the biochemical process. The expression of SIRT1, PGC-1alpha and MnSOD mRNA in hepatic tissues were detected with Real-time PCR assay. SIRT1, PGC-1alpha protein and 8-OHdG expressions were determined with the immunohistochemical method. The SOD level in hepatic tissues was tested by the xanthine oxidase method. The MDA content in hepatic tissues was examined by the thiobarbituric acid method. RESULT: The contents of TG, CHOL, NAFLD activity scores and ALT level in serum in hepatic tissues of mice in the model induced by fat-rich diet were obviously higher than that of the normal group (P < 0.010. The SIRT1, PGC-1alpha, MnSOD mRNA and protein expression in hepatic tissues were significantly lower than that of the normal group (P < 0.01). The expression of 8-OHdG and the content of MDA in hepatic tissues were obviously higher than that of the normal group (P < 0.01). After the intervention with different doses of PTFC, the NAFLD activity scores, the content of TG and the level of AST in serum were notably lower than that of the normal group (P < 0.01, P < 0.05); whereas the SIRT1, PGC-1alpha, MnSOD mRNA and protein expression were obviously higher than that of the normal group (P < 0.01, P < 0.05), with the significant decrease in the expression of 8-OHdG and the content of MDA (P < 0.01). CONCLUSION: Oxidative stress/lipid peroxidation enhancement in in NASH mice induced by high-fat diet may be related to the changes in SIRT1/PGC-1alpha signal transduction pathway. PTFC could enhance the anti-oxidant capacity in liver, relieve the damage of reactive oxygen during the fatty acid metabolic process, and prevent NASH from the occurrence and development by regulating the SIRT1/PGC-1alpha signal pathway.