Jasmine tea extract prevents CUMS-induced depression-like behaviors through the modulation of microbiota-gut-brain axis

Depression is strongly linked to dysfunctions in the microbiota-gut-brain axis. Jasmine tea, a traditional Chinese beverage made by combining green tea with Jasminum sambac, has potential antidepressant effects. However, its potential to alleviate depression via modulation of the microbiota-gut-brain axis remains largely unstudied. In this study, we used a rat model of depression induced by chronic unpredictable mild stress (CUMS) to investigate the effects of jasmine tea extract (JT) on depression-related symptoms. Behavioral assessments, inflammatory marker analysis, hippocampal histology, and brain-derived neurotrophic factor (BDNF) expression assays demonstrated that JT alleviated depressive behaviors, reduced brain tissue damage, and restored cognitive function in CUMS-exposed rats. JT also significantly reduced intestinal levels of pro-inflammatory cytokines (IL1 beta, IL-6, and TNF-alpha) and modulated oxidative stress markers (MDA, SOD, and CAT), suggesting a role in preserving intestinal integrity. Further, 16S rRNA sequencing revealed that JT shifted the gut microbiota composition in favor of beneficial bacteria such as Romboutsia, Blautia, and Monoglobus, while decreasing the abundance of potentially harmful bacteria, including Bifidobacterium, Clostridium_sensu_stricto_1, and Escherichia-Shigella. Meanwhile, non-targeted and targeted metabolomics analyses showed that JT influenced key metabolic pathways involving tryptophan, short-chain fatty acids, and bile acids, helping to restore metabolic balance across various tissues (feces, colon, serum, and cerebral cortex) in the depressed rats. These findings indicate that JT may alleviate depression by modulating the microbiota-gut-brain axis, highlighting its potential as a dietary intervention for depression management.