Regulatory effects of Ganoderma atrum polysaccharides on LPS-induced inflammatory macrophages model and intestinal-like Caco-2/macrophages co-culture inflammation model

Lipopolysaccharide (LPS)-induced inflammatory macrophages model and intestinal-like Caco-2/macrophages co-culture inflammation model were established to evaluate the anti-inflammatory effect and underlying mechanism of Ganoderma atrum polysaccharides (PSG-1). It was found that PSG-1 reduced LPS-induced secretion of pro-inflammatory cytokine (TNF-α, IL-6 and IL-1β), ROS levels, and inhibited the expression of COX-2 in LPS-stimulated inflammatory macrophages model and intestinal-like Caco-2/macrophages co-culture inflammation model. Furthermore, PSG-1 suppressed the LPS-induced activation of MAPKs signaling pathways, and regulated oxidative stress by activating the Nrf2/Keap1 signaling pathways. These above results indicated that PSG-1 not only has a direct anti-inflammatory effect in LPS-induced inflammatory macrophages model, but also has an indirect anti-inflammatory effect in intestinal-like Caco-2/macrophages co-culture inflammation model. These findings provide new insight of the mechanism underlying the anti-inflammatory activities of PSG-1, and facilitated the expansion of the application of PSG-1 in natural functional food.