Antidepressant-like effects of the extract from Cimicifuga foetida L.

Ethnopharmacological relevance: Cimicifuga foetida L., a traditional Chinese medicine, has been developed for the treatment of perimenopausal symptoms including depression in China (Brand name: XIMINGTING®, XMT). The primary active constituents are believed to be the triterpene glycosides. Nevertheless, there are no studies about the antidepressant-like effects of XMT in rodents. The present study aimed to evaluate antidepressant-like effects of XMT. Antidepressant-like activity of XMT was studied using forced swimming test (FST) and tail suspension test (TST) in female mice, as well as chronic mild stress (CMS) procedure in female rats. In addition, 5-hydroxytryptophan (5-HTP)-induced head-twitch test and yohimbine toxicity potentiation test in female mice were conducted to propose the possible serotonergic or noradrenergic mechanisms in the antidepressant-like effects of XMT. In mice, XMT was administrated acutely and for 7 consecutive days (20, 40 and 80 mg/kg/day, p.o.); and in rats for 28 consecutive days (10, 20 and 40 mg/kg/day, p.o.). XMT significantly reduced immobility duration in FST and TST without affecting locomotor activity, increased swimming and climbing durations in FST, and enhanced 5-HTP-induced head-twitch response while did not affect yohimbine-induced lethality in female mice. XMT also normalized the inhibition of sucrose intake and decreased the levels of plasma adrenocorticotropic hormone and serum corticosterone and adrenal gland weight in CMS-treated female rats. These data indicate XMT processes antidepressant-like properties in rodents, which could be related to its serotonergic and noradrenergic activation and normalization of the hypothalamic-pituitary-adrenal axis.