miR-122-5p regulates hepatocytes damage caused by BaP and DBP co-exposure through SOCS1/STAT3 signaling in vitro.

BaP and DBP are ubiquitously and contemporaneously present in the environment. However, Current studies largely concentrate on the effects of a single pollutant (BaP or DBP). The liver is vital for biogenic activities. The effects of BaP and DBP co-exposure on liver remain unclear. Thus, we treated human normal liver cell (L02 cell) with BaP or/and DBP. We found that compared to individual exposure, co-exposure to BaP and DBP induced further increased levels of AST and ALT. BaP and DBP co-exposure caused further increased levels of IL-2, IL-6, and TNF-α, decreased IL-10 level, and a higher percentage of apoptotic cells and S-phase arrest cells. BaP and DBP co-exposure worsen the decrease of miR-122-5p level and chaos of SOCS1/STAT3 signaling. Dual-luciferase reporter gene assays showed that SOCS1 was a validated target of miR-122-5p. miR-122-5p overexpression alleviated the increased SOCS1 expression, decreased phospho-STAT3 expression, decreased IL-10 level, increased TNF-α levels, increased percentage of apoptosis and S-phase arrest, and cytotoxicity induced by BaP and DBP co-exposure in hepatocytes. These results suggested that miR-122-5p negatively regulated the synergistic effects on apoptosis and disorder of inflammatory factor secretion involved in hepatocyte injury caused by BaP and DBP co-exposure through targeting SOCS1/STAT3 signaling.