TEC-mediated tRF-31R9J regulates histone lactylation and acetylation by HDAC1 to suppress hepatocyte ferroptosis and improve non-alcoholic steatohepatitis.

Background: Tectorigenin (TEC) is a monomer of anthocyanin, which we found exhibits hepatoprotective effects. tRNA-derived fragments (tRFs) and ferroptosis play important roles in the pathogenesis of non-alcoholic steatohepatitis (NASH). Recent discoveries have revealed that histone lactylation and acetylation play a crucial role in connecting cellular metabolism and epigenetic regulation through post-translational modification of histones. However, it is unclear whether TEC improves NASH by regulating histone lactylation, acetylation and hepatocyte ferroptosis through tRFs.

Results: In this study, we demonstrated that TEC significantly inhibits free fatty acids-induced hepatocyte ferroptosis both in vitro and in vivo. We identified tRF-31R9J (tRF-31-R9JP9P9NH5HYD) involved in TEC regulation of ferroptosis in steatosis hepatocytes. Overexpression of tRF-31R9J suppressed hepatocyte ferroptosis and enhanced cell viability in steatosis HepG2 cells. Knockdown of tRF-31R9J partially counteracted the inhibitory effect of TEC on ferroptosis in hepatocytes. Mechanistically, tRF-31R9J recruited HDAC1 to reduce the levels of histone lactylation and acetylation modifications of the pro-ferroptosis genes ATF3, ATF4, and CHAC1, thereby inhibiting their gene expression.

Conclusions: This study demonstrates that TEC-mediated tRF-31R9J inhibits hepatocyte ferroptosis through HDAC1-regulated histone delactylation and deacetylation, thereby improving NASH. These discoveries offer a theoretical foundation and new strategies for the medical management of NASH.