Effect of mycelial extract of Clavicorona pyxidata on acetylcholinesterase and beta-secretase activity in vitro

In a previous study, an extract of Clavicorona pyxidata DGUM 29005 mycelia demonstrated an inhibitory effect against enzyme-associated perceptual disorders. We have attempted to determine whether this mycelial extract is also capable of inhibiting the activities of acetylcholinesterase (AChE) and beta-secretase (BACE) activity. Butanol, ethanol, and water extracts of C. pyxidata DGUM 29005 mycelia were shown to inhibit AChE activity by 99.3%, 93.7%, and 91.7%, respectively. The inhibitory value of the butanol extract was more profound than that of tacrine (95.4%). The ethanol extract also exerted an inhibitory effect against BACE activity; this fraction may harbor the potential for development into a pharmocotherapeutic modality for the treatment of Alzheimer's disease (AD) patients. Rat pheochromocytoma PC12 cells in culture were not determined to be susceptible to the cytotoxic activity evidenced by the mycelial extract. The ethanol extract inhibited endogenous AChE activity in PC12 cellular homogenates, with an IC50 of 67.5 microg/ml, after incubation with intact cells, and also inhibited BACE activity in a dose-dependent fashion. These results suggest that the C. pyxidata mycelial extract has the potential to enhance cholinergic function and, therefore, may perform a function in the amelioration of the cholinergic deficit observed in cases of AD, as well as other types of age-associated memory impairment.