ABSTRACT
Objective To investigate the role of interleukin-22 (IL-22)-regulated autophagy in hydrogen peroxide (H2 O2 )-induced hepatocarcinoma cell damage. Methods HepG2 cells were transfected with pEGFP-LC3 and then cultured in RPMI 1640 medium free of fetal bovine serum (FBS) or containing 1％ or 10％ FBS. These cells were pretreated with rapamycin or an autophagy inhibitor (3-MA) and then stimulated with recombinat human IL-22 (rhIL-22). GFP-LC3 puncta formation and autophagy signaling ac-tivation were measured. MTT assay was performed to detect cell viability. Results rhIL-22 significantly promoted GFP-LC3 puncta formation and LC3-Ⅱ expression in HepG2 cells treated with different stimulation protocols. The autophagy pathway inhibitor, 3-MA, dramatically suppressed the rhIL-22-activated autophagy signals. rhIL-22 attenuated H2 O2-mediated HepG2 cell death and that could be inhibited by 3-MA. Conclu-sion IL-22 promoted the activation of autophagy signaling pathways and alleviated H2 O2-mediated HepG2 cell damage.