Glycyrrhizic acid ameliorates the kynurenine pathway in association with its antidepressant effect.

Glycyrrhizic acid ameliorates the kynurenine pathway in association with its antidepressant effect. Behav Brain Res. 2018 Jan 20;: Authors: Wang B, Lian YJ, Dong X, Peng W, Liu LL, Su WJ, Gong H, Zhang T, Jiang CL, Li JS, Wang YX Abstract Our previous study implied the role of central high mobility group box 1 (HMGB1) in lipopolysaccharide (LPS)-induced depressive behavior that could partially abrogate by glycyrrhizic acid (GZA). Here, we considered the potential mechanism underlying GZA ameliorating chronic stress-induced depression both in vivo and in vitro. Depression model was established with the 4-week chronic unpredictable mild stress (CUMS) mice or low dose of LPS/HMGB1 administration slices. Sucrose preference test, tail suspension test and open field test were performed to reflect depressive behaviors. Enzyme activity of indoleamine-2,3-dioxygenase (IDO) was recorded with the ratio of kynurenine (KYN) / tryptophan (Trp). Transcription of gene was evaluated by RT-PCR. Along with depressive behavior, IDO, the rate-limiting enzyme of the kynurenine pathway (KP), was upregulated at the level of mRNA expression, and enzyme activity was also elevated in stressed hippocampi and LPS-treated hippocampus slices. Treatment of mice with GZA, the inhibitor of HMGB1, prevented the activated enzymes in KP and the development of depressive-like behaviors. These experiments demonstrate that GZA may restrain HMGB1 thus improving chronic stre...
Source: Behavioural Brain Research - Category: Neurology Authors: Tags: Behav Brain Res Source Type: research