Ganoderic acid W

Background: To study the protective effects of ganoderic acid A (GAA) on bleomycin (BLM)-induced pulmonary fibrosis. Methods: ICR mice were intratracheally instilled with BLM to induce pulmonary fibrosis on day 0. Then the mice were orally given GAA (25, 50 mg/kg) or dexamethasone (2 mg/kg). After treatment for 21 days, the mice were sacrificed. Wet dry weight (W/D) ratio of lung was used to detect pulmonary edema. Myeloperoxidase (MPO), interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), and superoxide dismutase (SOD) were detected by enzyme-linked immunosorbent assay. Hematoxylin and eosin staining was used to evaluate the pathological changes. The levels of transforming growth factor β (TGF-β), phosphorylated-smad3 (p-smad3), p-IκB, and p-nuclear factor-kappa B (NF-κB) in lung tissue were detected by western blot. Results: GAA treatment significantly improved MPO activity, W/D ratio, and lung histopathology. The protective effect of GAA may be related to downregulation of TNF-α, IL-1β, IL-6, MDA and upregulation of SOD. In addition, GAA significantly decreased the levels of TGF-β, p-smad3, p-IκB, and p-NF-κB, compared with those in BLM group. Conclusion: GAA has protective effect on BLM-induced lung injury, and TGF-β/Smad-3/NF-κB signaling pathway may play an important role in the pathogenesis of BLM-induced lung injury.

Type II ganoderic acids (GAs) produced by the traditional medicinal mushroom Ganoderma are a group of triterpenoids with superior biological activities. However, challenges in the genetic manipulation of the native producer, low level of accumulation in the farmed mushroom, the vulnerabilities of the farming-based supply chain, and the elusive biosynthetic pathway have hindered the efficient production of type II GAs. Here, we assemble the genome of type II GAs accumulating G. lucidum accession, screen cytochrome P450 enzymes (CYPs) identified from G. lucidum in baker's yeast, identify key missing CYPs involved in type II GAs biosynthesis, and investigate the catalytic reaction sequence of a promiscuous CYP. Then, we engineer baker's yeast for bioproduciton of GA-Y (3) and GA-Jb (4) and achieve their production at higher level than those from the farmed mushroom. Our findings facilitate the further deconvolution of the complex GA biosynthetic network and the development of microbial cell factories for producing GAs at commercial scale.

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a serious respiratory disease, the mechanism is unclear. This paper revealed the mechanism of ganoderic acid B (BB) on lipopolysaccharide-induced pneumonia in mice. Pneumonia model was induced by LPS in mice and A549 cells. Lung dry/wet weight (W/D) and myeloperoxidase (MPO) activity in lung were examined. Lung histopathological changes was observed by HE staining. Superoxide dismutase (SOD), malondialdehyde (MDA) and proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in mice and A549 cells were detected. Rho/NF-κB pathway in mice and A549 cells were examined by Western Blot. BB significantly reduced W/D and MPO activity, restored lung histopathological changes. BB also increased SOD, decreased MDA, TNF-α, IL-1β and IL-6 in mice and A549 cells. In addition, BB inhibited Rho/NF-κB pathway in mice and A549 cells. BB has protective effect on LPS-induced pneumonia in mice, and its mechanism is related to the regulation of Rho/NF-κB signaling pathway.