Dendrobium officinale polysaccharides alleviate depression-like symptoms via regulating gut microbiota-neuroinflammation in perimenopausal mice

Dendrobium officinale is one of the famous functional food for its anti-inflammatory effects. However, it is unclear whether Dendrobium officinale could reverse depression-like symptoms during the perimenopausal period. The present study investigated the effects of Dendrobium officinale polysaccharides (DOP) in a mouse perimenopausal depression model by ovariectomy and chronic mild stress. The results showed that DOP attenuated depressive-like behaviors and modulated the gut microbiota composition in perimenopausal mice. In addition, ovariectomy plus chronic mild stress enhanced the release of proinflammatory cytokines and the activation of microglia in the prefrontal cortex, while DOP treatment significantly reversed the neuroinflammation. Furthermore, DOP alleviated the elevation of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and corticosterone levels in serum, suggesting the restoration of the hypothalamic-pituitaryadrenal (HPA) axis by DOP. Taken together, these findings suggested that DOP might be an alternative diet therapy for perimenopausal depression via regulating gut microbiota-neuroinflammation.