Anti-inflammatory and anti–lung cancer activities of low-molecular-weight and high-sulfate-content sulfated polysaccharides extracted from the edible fungus Poria cocos

Sulfated polysaccharides (SPSs) have excellent physicochemical properties, attracting research interest in the pharmaceutical industry. A previous study extracted SPS (named Suc40) from the edible fungus, Poria cocos and demonstrated that it exhibited anti-inflammatory and anticancer activities. In this study, three fractions of Suc40, Suc40 F1, Suc40 F2, and Suc40 F3, with different molecular weights and sulfate contents were prepared through gel-filtration column chromatography. The molecular weights of F1, F2, and F3 were approximately 616.23, 82.57, and 6.21 kDa, respectively, and their sulfate content were 0.23, 1.65, and 1.90 mmol/g, respectively. The fractions' anti-inflammatory activities were determined by assessing their ability to suppress inflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Suc40 F2 and Suc40 F3 suppressed interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) production by 60 % and 35 %, respectively. Suc40 F2 and Suc40 F3 suppressed protein kinase B (AKT)/p38 and p38 signaling, which resulted in anti-inflammatory effects. The fractions' anti-lung cancer activity was evaluated by assessing their H1975 cell proliferation inhibition. Suc40 F3 at a concentration of 800 μg/ml exhibited maximal cell proliferation inhibition. The low molecular weight and high sulfate content of Suc40 F3 were associated with its enhanced anti-inflammatory and anti-lung cancer activities.