Structure-Based Virtual Screening of Sterols and Triterpenoids Isolated from Ganoderma (Agaricomycetes) Medicinal Mushrooms Shows Differences in Their Affinity for Human Glucocorticoid and Mineralocorticoid Receptors

An extensive database of sterols and triterpenoids isolated from Ganoderma mushrooms was evaluated by in silico structure-based virtual screening to determine their respective ligand affinities for the glucocorticoid or mineralocorticoid receptor (GCR or MNR). The main ligands for GCR in our database were ergosta-7,22-dien-3-one (compound 1) and ganodermaside B (compound 2), while the best ligands for MNR were 2β,3α,9α-trihydroxyergosta-7,22-diene (compound 8) and 5α-ergosta-7,22-dien-3β-ol (compound 3). The binding free energy (BFE) values calculated for such metabolites were similar to those of the natural ligands for each receptor (i.e., dexamethasone for GCR and aldosterone for MNR). Moreover, the differences between mean BFE values calculated for both receptors suggest that ergosta-7,22-dien-3-one (compound 1), ganodermaside B (compound 2), fungisterol (compound 5), ganoderic acid Ma (compound 9), and cerevisterol (compound 10) might be used as specific ligands for GCR, with a significantly lower affinity for MNR. Finally, it is worth noting that even though this work is exclusively theoretical, the reported bioactivities (either pro- or anti-inflammatory) for those metabolites that were previously studied are consistent with our findings, suggesting that the well-known immunomodulatory effect of Ganoderma triterpenoids and sterols might be attributed, at least partially, to their ability to act as specific GCR ligands.

In Vitro Expression of Toll-Like Receptors and Proinflammatory Molecules Induced by Ergosta- 7,22-Dien-3-One Isolated from a Wild Mexican Strain of Ganoderma oerstedii (Agaricomycetes)

Compounds showing pharmacological activity on the immune system are of interest because of their therapeutic potential in the treatment of many diseases. However, data from primary human immune cells and in vivo studies are limited. The aim of this study was to analyze the ability to induce the expression of Toll-like receptors (TLRs) and proinflammatory molecules on cells involved in the immune system using the compound ergosta-7,22-dien-3- one, isolated from a wild Mexican strain of Ganoderma oerstedii. According to our study, ergosta-7,22-dien-3-one did not present any cytotoxic effect on HeLa or J774A.1 cells, and it was able to stimulate nitric oxide production, induce the expression of genes, and induce the production of TLRs, cytokines, chemokines, and cellular adhesion molecules in J774A.1 cells, based on reverse-transcriptase polymerase chain reaction and enzyme-linked immunosorbent assay. Here we report a new pro-inflammatory property of ergosta-7,22-dien-3-one, which should be considered as a possible adjuvant property in view of its biological activity.