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Objective To explore the effect of FGF21 on MSG-induced nonalcoholic fatty liver diseases of inflammation and TLR4/p38MAPK signal pathway in rats.Methods Newborn SD rats were randomly divided into control group,MSG group and FGF21 group(n =10).Rats of MSG group and FGF21 group were adiministered with solution of MSG 4g/(kg · d) at 2nd,4th,6th,8th and 10th postnataldays.After being fed for thirteen weeks,rats of FGF21 group was intraperitoneal injected with FGF21 1 mg/(kg · d) for a continuous 32 days.Liver pathology of the rats was analyzed by HE staining.The liver weight,aminotrasferases were observed.The expression of IL-6,TNF-α,TLR4,p38MAPK in liver tissue were determined by fluorescence quantitative PCR and Western blot.Results Compared with the control group,liver tissues of the MSG group changed to bullous steatosis and had inflammatory cell infiltration,the liver weighted,serum activities of ALT,AST,ALP were increased (P ＜ 0.01,P ＜ 0.01,P ＜ 0.01,P ＜ 0.01).The expression of IL-6,TNF-α,TLR4,p38MAPK mRNA and protein expression of TLR4,p38MPAK,p-p38MAPK in rats hepatocyte were increased than those in control group (P ＜ 0.01).After reatment with FGF21,the bullous steatosis and inflammatory cell,liver weighted,serum activities of ALT,AST,ALP were signficantly decreased (P ＜ 0.05,P ＜ 0.01,P ＜ 0.01,P ＜ 0.05),and the levels of IL-6,TNF-a,TLR4,p38 MAPK mRNA and protein expression of TLR4,p38-MPAK,p-p38MAPK were reduced than those of MSG group(P ＜0.01).Conculsion The FGF21 may regulate MSG-induced NAFLD of inflammation through TLR4/p38MAPK signaling pathway in rats.
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To investigate the effect of fibroblast growth factor 21 (FGF21) on hepatic fibrosis in mice and the mechanism of its action.Methods Male ICR mice were randomly divided three groups : control group, model group (treated with CCl4 ), and treatment group (treated with CCl4 +1.0 mg/kg FGF21).All mice were sacrificed to collect serum and liver tissues after 36 consecutive days of treatment.Serum levels of alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TBil), interleukin -6 (IL -6), interleukin -1β(IL -1β), and tumor necrosis factor -α(TNF -α) were measured.Liver pathological changes were analyzed by Masson staining .The hepatic 4 -hydroxyproline (4 -Hyp) level was measured using a hydroxyproline detection kit.The mRNA levels of hepatic collagen I, α-smooth muscle actin (α-SMA), transforming growth factor -β(TGF -β), IL -6, IL - 1β, and TNF -αwere determined by quantitative real -time PCR.Comparison between multiple groups was made by one -way analysis of variance, and comparison between any two groups weas made using the LSD -t test.Results The Masson staining showed that the model group had a significantly higher degree of hepatic fibrosis than the control group , and the treatment group had a significantly lower degree of hepatic fibrosis than the model group.The model group had significantly higher serum levels of ALT , AST, ALP, and TBil (all P <0.05),and the treatment group showed significant reductions in the above parameters compared with the model group (all P <0.05).Enzyme - linked immunosorbent assay indicated that the model group had significantly higher serum levels of IL -1β, IL -6, and TNF -αthan the control group (all P <0.05), and the treatment group showed significant reductions in the above parameters compared with the model group (all P <0.05).The hepatic 4 -Hyp level and mRNA levels of collagen I and α-SMA were significantly higher in the model group than in the control group (P =0.04, <0.001, and <0.001), and they were significantly lower in the treatment group than in the model group (P =0.005, <0.001, and <0.001).The hepatic mRNA levels of TGF -β, IL -6, IL -1β, and TNF -αwere significantly higher in the model group than in the control group(all P <0.001), and they were significantly lower in the treatment group than in the control group (all P <0.001).Conclusion FGF21 attenuates hepatic fibrogenesis in mice, possibly by inhibiting the expression of TGF -β, IL -6, IL - 1β, and TNF -αin the liver.
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ObjectiveTo investigate the inhibitory effect of fibroblast growth factor-21 (FGF-21) on the carcinogenesis of L02 cells induced by diethylnitrosamine (DEN).Methods L02 cells were cultured and treated with different concentrations of DEN (1,10,20,50,100,and 150 μmol/L).MTT assay was used to measure the influence of DEN on the viability of L02 cells,and an appropriate stimulation concentration of DEN (20 μmol/L) was selected for further study.The malondialdehyde (MDA) and superoxide dismutase (SOD) detection kits were used to measure the levels of MDA and SOD in L02 cells treated by DEN (20μmol/L) and normal L02 cells.Then L02 cells were divided into model control group (treated with 20μmol/L DEN and PBS),low-dose FGF-21 group (20 μmol/L DEN + 1 μmol/L FGF-21),and high-dose FGF-21 group (20 μmol/L DEN +2 μmol/L FGF-21).The levels of MDA and SOD were measured after 12 hours of cell culture.Real-time PCR and Western blot were used to measure the expression of βKlotho (KLB),and Western blot was used to measure the level of phosphorylated protein kinase B (p-AKT).The t-test was used for comparison of continuous data between two groups;an analysis of variance was used for comparison between multiple groups,and the least significant difference t-test was used for further comparison between two groups.Results There was a significant increase in the level of MDA and a significant reduction in the level of SOD after L02 cells were treated with DEN (t =9.336 and 16.281,P =0.011 and 0.004).Compared with the model control group,the low-and high-dose FGF-21 groups had a significant reduction in the level of MDA and a significant increase in the level of SOD (P ＜ 0.05),and compared with the low-dose FGF-21 group,the high-dose FGF-21 group had a significantly lower level of MDA and a significantly higher level of SOD (P =0.030 and 0.042),and there was a significant difference between two groups.The high-and low-dose FGF-21 groups had significantly higher mRNA expression of KLB than the model control group (P ＜ 0.001),and the high-dose FGF-21 group had significantly higher mRNA expression of KLB than the low-dose FGF-21 group (P ＜ 0.001),and there was a significant difference between two groups;the protein expression of KLB showed the same trend.The model control group had a significantly higher level of p-AKT than the other two groups (P ＜0.05),and the high-dose FGF-21 group had a significantly lower level of p-AKT than the low-dose FGF-21 group (P ＜ 0.05).Conclusion DEN can increase oxidative stress in L02 cells.By upregulating the expression of KLB,FGF-21 can reduce the level of p-AKT,inhibit oxidative stress in L02 cells induced by DEN,and thus inhibit the development of hepatocellular carcinoma.
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@#ObjectiveTo investigate the role of serine/threonine kinase (Akt) and lipoprotein lipase (Lpl) in formation of nonalcoholic steatohepatitis (NASH) in rat with a fat-rich diet.Methods40 male Wistar rats were randomly divided into the 8-week-rich-fat group (n=10), 8-week-common-diet control group (n=10), 12-week-rich-fat group (n=10) and 12-week-common-diet control group (n=10). The lipid, cholesterol, glucose and insulin were examined, insulin resistance index (IRI) and insulin sensitivity index (ISI) were calculated, the expression of Akt and Lpl were detected with immunohistochemical method and morphological changes of liver were observed by transmission electron microscope (TEM).ResultsNASH was formed in each rat of 8-week-rich-fat group with characteristics of individual obese, increased liver volume, full and clear contour, gray-yellowish luster, greasy section and crisp quality. And it was accompanied by high lipoidemia (HL), liver fat cell denaturation, inflammatory cell infiltration in liver lobuler and cell death in liver. The expression of Akt was obviously reduced and the expression of Lpl was obviously weakened in liver. Lipid, cholesterol, glucose and insulin and IRI were gradually advancing. ISI was reducing and the insulin resistance formed. The data of fat-rich diet groups was significantly different with that of common-diet control groups (P<0.0001).Conclusion Steatohepatitis and insulin resistance can form in rat by feeding with rich-fat diet for 8 weeks. It causes the insulin and Lpl activeness reducing, and steatolysis barrier.
