[Expression and significance of insulin-like growth factor-1 and insulin-like growth factor binding protein-3 in hepatocyte steatosis model].

Objective To investigate the expression of IGF-1 and IGFBP-3 in nonalcoholic fatty steatosis hepatocyte models induced by oleic acid.Method Nonalcoholic fatty steatosis hepatocyte models induced by oleic acid on immortalized human hepatocyte,Oil red O staining and intracellular triglycerides were detected for observing the situation of IHH cells fatty degeneration.IHH cells were divided into control group,NAFLD group,which the control group cultured in DMEM/F12 medium,NAFLD group were treated with oleic acid,0.5 mmol / L treatment for 72 h.The expression ofmRNA and protein ofIGF-1 and IGFBP3 were measured by immunofluorescent staining,Western blot and RT-PCR methods.Between the two groups were compared using the t- test.Results The steatosis models of the hepatocytes were established successfully with 0.5 mmol/L oleic acid.Lipid droplets were observed through Oil red O staining.The level ofhepatocyte TG was increased (275.7 ± 27.2) μtg/mg from (150.2 ± 15.6) μg/mg (t =21.67,P ＜ 0.01).Compared with the control group,the mRNA of IGF-1 (0.76 ± 0.04 vs 4.82 ± 1.51,t =17.915,P ＜ 0.01),IGFBP-3 (1.58 ± 0.93 vs 5.41 ± 1.37,t =12.893,P ＜ 0.01) and protein expression of IGF-1 (1.00 ± 0.29 vs 2.56 ± 0.71,t =29.17,P ＜ 0.01),IGFBP-3 (0.65 ± 0.36 vs 1.23 ± 0.91,t =32.12,P ＜ 0.01) significantly decreased in oleic acidtreated group.The results of immunofluorescence staining also confirm the significantly decreased protein expression of IGF-1 and IGFBP-3 in NAFLD group compared with control group.Conclusion The expression of IGF-1 and IGFBP-3 decreased in nonalcoholic fatty steatosis hepatocyte models,which will provide the experimental basis for the further study of the mechanism of the limited height of some children with nonalcoholic fatty liver disease in clinical. Key words: Fatty liver; Insulin-like growth factor-1; Insulin-like growth factor binding protein-3; Immortalized human hepatocyte cells