Changes of suppressors of cytokine signaling-3 and sterol regulatory element binding proteins-1c pathway in steatosis HepG2/HepG2.2.15 cells

Objective To investigate the effects of HepG2 and HepG2.2.15 cells steatosis on the mRNA and protein expressions of suppressors of cytokine signaling-3(SOCS-3) and sterol regulatory element binding proteins (SREBP-1c). Methods The cell model of chronic hepatitis B (CHB) combined with nonalcoholic fatty liver disease (NAFLD) was successfully constructed using an oleic acid-induced HepG2 and HepG2.2.15 cells steatosis. Cells were divided into HepG2 cell control group (HepG2 cell control group), HepG2.2.15 cell control group (HepG2.2.15 cell control group), HepG2 cell steatosis group (HepG2 cell steatosis group) and HepG2.2.15 cell steatosis group (HepG2.2.15 cell steatosis group). The expression levels of SOCS-3 and SREBP-1c mRNA were detected by real-time quantitative polymerase chain reaction (PCR). Changes in protein expressions of SOCS-3 and SREBP-1c were measured by western blot. Results SOCS-3 mRNA expression level in HepG2.2.15 cell control group was significantly lower than that in HepG2 cell control group (P<0.01). The level in HepG2 cell steatosis group was also significantly lower than that in HepG2 cell control group (P<0.01). However, the level of SOCS-3 mRNA in HepG2.2.15 cell steatosis group was lower than HepG2.2.15 cell control group with no statistical significance (P=0.173). There was interaction between cells and steatosis (F=25.547, P<0.01). The expression of SREBP-1c mRNA in HepG2.2.15 cell control group was significantly lower than that in HepG2 cell control group (P<0.01), and was significantly higher in HepG2.2.15 cell steatosis group than that in HepG2.2.15 cell control group (P<0.01). There was no significant difference between HepG2 cell steatosis group and HepG2 cell control group (P=1.000). There was interaction between cells and steatosis (F=5.04, P<0.05). Western blot analysis showed that protein levels of SOCS-3 and SREBP-1c in steatosis cells at 48 h and 72 h were significantly higher than those in non-alcoholic steatosis cells. Conclusions Protein expressions of SOCS-3 and SREBP-1c are up-regulated in both steatosis groups. Factorial analysis shows that there is interaction between cells and steatosis. HBV gene could inhibit SOCS-3 mRNA expression and promote the expression of SREBP-1c mRNA in steatosis cells. Key words: Hepatitis B; Fatty liver; SOCS-3; SREBP-1c