Autophagy modulation in resveratrol protective effects on steroidogenesis in high-fat diet-fed mice and HO-challenged TM3 cells.

Background: Autophagy dysregulation and oxidative stress play critical pathophysiological roles in developing obesity-related metabolic health disorders. This study aims to investigate how autophagy modulation is related to resveratrol (RSV) antioxidant activities and preventive effects on steroidogenesis decline associated with a high-fat diet (HFD) and oxidative damage.

Methods And Results: Eight-week-old C57BL/6 J male mice were fed with HFD with or without supplement RSV (400 mg/kg/day) by gavage for 16 weeks. The control group was fed with a standard diet with no RSV or the same amount of RSV. Mouse Leydig cell line TM3 cell was used for in vitro studies. Oxidative stress was induced in TM3 cells with HO, followed by RSV treatment plus autophagy activator rapamycin or autophagy inhibitor 3-methyladenine, respectively. RSV supplement could upregulate proteins level of StAR and mitochondrial proteins COX4 and mtTFA, indicating the amelioration of steroidogenesis decline and mitochondrial dysfunction caused by HFD. Antioxidants such as GPx4 and SOD2 were improved by RSV as well. The observation of autophagosomes and the changes in expressions of LC3II/I, Beclin1, and Atg7 indicated that RSV could reverse the autophagy defect associated with HFD. 3-methyladenine inhibition of autophagy partially abolished RSV protection on mitochondrial function and steroidogenesis in HO-challenged TM3 cells. However, the combination use of rapamycin and RSV did not improve protection on Leydig cells against oxidative damage.

Conclusions: The stimulation of autophagy by RSV is closely linked to its antioxidant actions and positive impact on steroidogenesis in HFD mice. The findings suggest RSV is protective against obesity-related Leydig cell impairment.