The role of hepatitis B virus surface protein in inducing Sertoli cell ferroptosis

Hepatitis B virus infection could result in male infertility by inhibiting sperm function and viability. Sertoli cell death contributes to spermatogenesis impairment, which is associated with sperm defects and dysfunction. Ferroptosis-mediated cell death of Sertoli cells was found to contribute to spermatogenesis disorder and poor sperm quality. However, the effects of hepatitis B virus infection on ferroptosis of Sertoli cells remain to be elucidated. Human Sertoli cells were cultured in vitro with 25, 50, and 100 mg/mL of hepatitis B virus surface protein for 48 hours. Cell viability was measured with CCK-8. Levels of glutathione, malondialdehyde, iron, and m6A in human Sertoli cells were determined. Lipid peroxidation was assessed using C11-BODIPY. Luminescence analysis was performed to detect the binding of METTL3 and 3{cents}-UTR of TRIM37 containing the m6A motifs. Immunoprecipitation was applied to determine the relationship between TRIM37 and GPX4. qPCR and immunoblotting were performed to measure mRNA and protein levels. Hepatitis B virus surface protein exposure significantly increased TRIM37 expression, malondialdehyde level, and ferroptosis, and decreased cell viability and glutathione level of human Sertoli cells. TRIM37 silencing inhibits the effect of HBs exposure-regulated cell viability and ferroptosis in human Sertoli cells. TRIM37 inhibits GPX4 expression through ubiquitination. GPX4 overexpression inhibits the effect of TRIM37 on cell viability and ferroptosis in human Sertoli cells. Administration of ferroptosis inhibitor recovers the cell viability decreased by TRIM37. Mechanism study showed HBs increases the level of TRIM37 3-UTR m6A by promoting the expression of METTL3, and the binding of m6A reader IGF2BP2 and TRIM37 3-UTR promotes the stability of TRIM37 mRNA.HBs inhibit Sertoli cell viability by promoting ferroptosis of Sertoli cells through TRIM37-mediated ubiquitination of GPX4. The findings highlight the importance of TRIM37/GPX4 signaling in the ferroptosis of Sertoli cells.