[Effect of interfering hepatocyte nuclear factor-1 alfa in HepG2 on the expressions of apoM, apoA-I and the correlative key enzyme of cholesterol metabolism]

Abstract

To determine wether there were connections among hepatocyte nuclear factor-1 alfa (HNF-1a), liver receptor homolog-1 (LRH-1), apolipoprotein M (apoM) and to investigate the effects of HNF-1a in HepG2 on the expressions of apoM, apolipoprotein A-I (apoA-I) and the key enzymes in cholesterol metabolism and biotransformation. The mRNA expressions of apoM, LRH-1 and HNF-1a were detected by RT-PCR. HNF-1a was interfered and RT-PCR was used to detect the changes of apo M, apo A-I, Cyp7A1, farnesoid X receptor (FXR) and small heterodimer partner-1 (SHP-1). Western blot was used to detect the change of apo M protein. The expressions of apoM, LRH-1 and HNF-1amRNA were obviously higher in HCC tissue than that in para-cancer tissue (the vaule of t is -7.167, -7.075, -8.803, P less than 0.01 respectively). HNF-1a and LRH-1 positively correlated with the expression of apoM (r=0.353, P less than 0.01; r=0.523, P less than 0.01 respectively); RT-PCR and western blot results showed that the expressions of apoM, FXR and SHP-1 mRNA, could be obviously suppressed by HNF-1a interfering as compared to the negative controls by 47.4%, 47.9%and 65.2% (P less than 0.01) respectively, and the expression of apoM protein also decreased by 54.3% (F = 43.482, P less than 0.01). The expressions of HMGCR and CYP7A mRNA increased by 101.1% and 138.5% (P less than 0.01) respectively as compared to the negative control. But there is no effect on expression of apoA-I mRNA (F = 0.170, P more than 0.05). HNF-1a could promote cholesterol biotransformation by increasing the expression of apoM and the key enzymes in cholesterol metabolism and decreasing inhibiting factor. So HNF-1a provided protection against cardiovascular disease.