The antidepressant‐like effects of Shen Yuan: Dependence on hippocampal BDNF–TrkB signaling activation in chronic social defeat depression‐like mice

Abstract

The aim of this paper is to elucidate the effects of SY treatment on chronic social defeat stress (CSDS)-induced depression-like symptoms and the related mechanism.Our results indicated that SY treatment reverses the depressive-like behaviors induced by CSDS as measured by the social interaction test, sucrose preference test, forced swim test, and tail suspension test. SY decreased the serum levels of CORT and increased hippocampal neurotransmitters (5-HT, DA, and NE) in CSDS mice.Meanwhile, SY upregulated the brain-derived neurotrophic factor (BDNF) signaling pathway and reversed the decreased hippocampal neurogenesis caused by CSDS. In addition, we found that the TrkB antagonist K252a fully blocked the SY effects on behavioral improvement and eliminated the promoting effects of SY on hippocampal neurogenesis and BDNF-TrkB signaling (including the downstream ERK and Akt pathways) activation, thus further demonstrating that BDNF-TrkB signaling was necessary for the SY effects. In conclusion, our study showed that SY acted as an antidepressant in mice exhibiting CSDS-induced depression-like symptoms, and its effect was facilitated by promoting hippocampal neurogenesis and BDNF signaling pathway activation.

Soy isoflavones alleviate lipopolysaccharide-induced depressive-like behavior by suppressing neuroinflammation, mediating tryptophan metabolism and promoting synaptic plasticity

“…The sucrose preference test was conducted as previously described. 17 Before the formal sucrose preference test, each mouse was simultaneously presented with two bottles, one filled with water (200 mL) and the other containing sucrose solution (1%, 200 mL) for 2 consecutive days. Then, all mice were deprived of water for 15 h prior to the test.…”

“…The sucrose preference test was conducted as previously described. 17 Before the formal sucrose preference test, each mouse was simultaneously presented with two bottles, one filled with water…”

Novel Pharmacological Approaches to the Treatment of Depression

“…Two flavonoids extracted from Tilia americana, a plant grown in North America that has been used to treat sleep disorders [303], showed significant antidepressant effects through the 5-HT1A and 5-HT2A receptors [304]. Panax ginseng, Polygala tenuifolia, Shen Yuan, and Fructus aurantii, are used in traditional Chinese medicine and were shown to activate BDNF and rescue rodents from depressive-like behaviors [305][306][307][308]. The herbal formula traditionally used in Thailand, Kleeb Bua Daeng, affected BDNF expression and proinflammatory factors in the PFC and the hippocampus [309].…”

Dietary intervention in depression – a review

“…However, Shen Yuan reversed the depression-like behavior induced by chronic social defeat stress in mice by enhancing the hippocampal neurogenesis and regulating the BDNF/TrkB signaling pathway. 38…”

“…However, Shen Yuan reversed the depression-like behavior induced by chronic social defeat stress in mice by enhancing the hippocampal neurogenesis and regulating the BDNF/TrkB signaling pathway. 38 It is well known that higher BDNF concentrations can improve cognitive function and regulate energy metabolism, 39 which are affected by diet and exercises. 40 Therefore, BDNF may be a mediator between the dietary intake and cognition.…”