Protective effect of Ganoderma atrum polysaccharide on acrolein-induced macrophage injury via autophagy-dependent apoptosis pathway

The study aimed to investigate the protective effect and underlying mechanism of Ganoderma atrum (G. atrum) polysaccharide (PSG-1) on macrophage injury induced by acrolein. The results showed that PSG-1 restored the cell viability damaged by acrolein. In addition, PSG-1 significantly reduced the acrolein-induced occurrence of Apoptosis via increase of Bcl-2 expression, mitochondrial membrane potential (MMP), decrease of ROS, cytochrome c (Cyt-C), Caspase-3, caspase-9. Moreover, the overexpressions of autophagy-related proteins (LC3, Beclin-1, Atg7 and Atg5) were suppressed by PSG-1, which demonstrated that PSG-1 inhibited Autophagy in acrolein treated macrophage. Beside, PSG-1 significantly elevated the expression level of p-mTOR, suggested that PSG-1 mediated Autophagy through mTOR pathway. Furthermore, inhibitor of Autophagy could inhibit Apoptosis in acrolein-induced macrophage, suggesting that Autophagy may be involved in the regulation of Apoptosis. In summary, the present study demonstrated that PSG-1 protected acrolein-induced macrophage injury via autophagy-dependent Apoptosis.