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

ABSTRACT

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 of mRNA and protein of IGF-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 of hepatocyte TG was increased (275.7+/-27.2) mug/mg from (150.2+/-15.6) mug/mg (t = 21.67, P less than 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 less than 0.01), IGFBP-3 (1.58+/-0.93 vs 5.41+/-1.37, t = 12.893, P less than 0.01) and protein expression of IGF-1 (1.00+/-0.29 vs 2.56+/-0.71, t = 29.17, P less than 0.01), IGFBP-3 (0.65+/-0.36 vs 1.23+/-0.91, t = 32. 12, P less than 0.01) significantly decreased in oleic acid-treated 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 non-alcoholic fatty liver disease in clinical.