Antidepressant-like effects of a water-soluble extract from the culture medium of Ganoderma lucidum mycelia in rats
1 Laboratory of Pharmacology, Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan
2 Laboratory of Immunobiochemistry, Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan
3 Noda Shokukin-kogyo Co. Ltd.; 295 Nanakodai, Noda, Chiba 278-0051, Japan
BMC Complementary and Alternative Medicine 2013, 13:370 doi:10.1186/1472-6882-13-370Published: 26 December 2013
Ganoderma lucidum is a popular medicinal mushroom used for promoting health and longevity in Asian countries. Previously, we reported that a water-soluble extract from a culture medium of Ganoderma lucidum mycelia (MAK) exerts antioxidative and cerebroprotective effects against ischemia–reperfusion injury in vivo. Here, we evaluated the antidepressant and anxiolytic activities of MAK in rats.
MAK (0.3 or 1 g/kg, p.o.) was administered in the experimental animals 60 min before the forced swimming, open-field, elevated plus-maze, contextual fear-conditioning, and head twitch tests. Additionally, the mechanisms involved in the antidepressant-like action of MAK were investigated by the serotonin precursor 5-hydroxy-L-tryptophan (5-HTP)- or 5-HT2A agonist (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI)-induced head twitch responses.
Treatment with MAK (1 g/kg) exhibited antidepressant-like effects in the forced swimming test, attenuated freezing behavior in the contextual fear-conditioning test, and decreased the number of head twitches induced by DOI, but not with 5-HTP. No significant response was observed in locomotion or anxiety-like behavior, when the animals were evaluated in the open-field or elevated plus-maze test, respectively.
These data suggest that MAK has antidepressant-like potential, which is most likely due to the antagonism of 5-HT2A receptors, and possesses anxiolytic-like effects toward memory-dependent and/or stress-induced anxiety in rats.