Ganoderma tsugae supplementation alleviates bronchoalveolar inflammation in an airway sensitization and challenge mouse model

Ganoderma tsugae (a Chinese mushroom Songshan lingzhi) cultivated in Taiwan is extensively used in Chinese traditional medicine to treat different diseases. To determine whether G. tsugae has anti-inflammatory effects on bronchoalveolar inflammation in vivo, we investigated the anti-inflammatory effects of G. tsugae products, YK01 and YK07, on bronchoalveolar inflammation using an airway sensitization and challenge mouse model. Female BALB/c mice were weekly sensitized by intraperitoneal injection of ovalbumin (OVA) three times and challenged with aerosolized OVA twice. Differential cell counts of infiltrating leukocytes, inflammatory mediators, cytokines in bronchoalvelor lavage fluid (BALF) of OVA-challenged mice were examined after continuously consuming G. tsugae diets for 5 weeks. We found that supplementation of G. tsugae significantly decreased total infiltrating leukocytes and lymphocyte percentage in BALF in the experimental groups. Supplementation of G. tsugae also significantly reduced inflammatory mediators in BALF including histamine, prostaglandin E2, eotaxin, and protein levels, however the levels of pro-inflammatory cytokines, interleukin (IL)-1β and IL-6, in BALF did not significantly change. These results suggest that both G. tsugae supplementation diets YK01 and YK07 might alleviate bronchoalveolar inflammation via decreasing the infiltration of inflammatory cells and the secretion of inflammatory mediators into the local tissues of lungs and airways. Further, these results indicate that the relief of bronchoalveolar inflammation in an airway sensitization murine model provides a possible therapeutic application for G. tsugae in allergic asthma.