Comparative analysis of β-Estradiol and testosterone on lipid droplet accumulation, and regulatory protein expression in palmitate/oleate-induced fatty HepG2 cells.

INTRODUCTION: The higher prevalence of non-alcoholic fatty liver disease (NAFLD) in men than women before menopause and the reduced difference post-menopause suggest that sex hormones may influence liver lipid accumulation. This study compared the effects of sex hormones on lipid droplet (LD) accumulation in palmitate/ oleate-treated HepG2 cells. METHODS: The MTT method was used to determine effective doses of palmitic and oleic acids in HepG2 cells, followed by a combined dose for inducing LD formation. Changes in LD content after treatment with various doses of β-estradiol and testosterone were evaluated qualitatively and semi-quantitatively using Oil Red O staining and light microscopy. The effects of these hormones on gene expression related to LD formation and lipogenesis, including PLIN2, ATGL, CGI-58, and CIDEB, were assessed using quantitative PCR. RESULTS: Treatment of HepG2 cells with palmitate and oleate increased LD accumulation and the expression of PLIN2 and CIDE while elevating ATGL expression without affecting CGI-58. With no significant difference, both β-estradiol and testosterone significantly reduced LD accumulation in steatotic HepG2 cells. Gene analysis indicated that both hormones decreased PLIN2 and increased CGI-58 expression. Testosterone did not affect CIDE, while β-estradiol reduced it at low doses. Combined treatment showed no significant changes in gene expression compared to individual hormone effects, but LD accumulation was synergistically reduced. CONCLUSION: This study demonstrates that β-estradiol and testosterone significantly modulate LD content and the expression of key regulatory genes in HepG2 cells, with β-estradiol showing a somewhat dominant role in enhancing lipid turnover and mitigating lipid accumulation.