👤 Junhu Hei

Electroconvulsive therapy (ECT) stands as the most effective intervention for treatment-resistant depression; however, its interaction with dietary regulation of the gut-brain axis has not been thoroughly explored. This study aimed to elucidate the mechanistic link between ECT, gut microbiota remodeling, short-chain fatty acid (SCFA) production, and neural plasticity. In this study, mice were subjected to chronic restraint stress (6 h/d for 28 consecutive days) to establish a depression-like model. Utilizing a translational approach that incorporated behavioral assessments, multimodal neuroimaging techniques such as PET-CT and laser speckle contrast imaging, along with multiomics analyses including metagenomics, metabolomics, and transcriptomics in rodent models, we demonstrated that ECT induced significant gut microbiota remodeling, characterized by an enrichment of SCFA-producing genera like Lactobacillus and Bifidobacterium. This remodeling was associated with restored intestinal barrier integrity and elevated plasma SCFA levels. Mechanistically, these microbial metabolites activated hippocampal Wnt/β-catenin signaling pathways, enhancing synaptic plasticity restoration, while concurrent probiotic supplementation further amplified brain-derived neurotrophic factor (BDNF) expression via SCFA-dependent epigenetic mechanisms. Neuroimaging corroborated the normalization of cerebral glucose metabolism and hemodynamic function post-ECT. In conclusion, our findings unveil a novel gut-brain communication pathway by which ECT exerts its antidepressant effects, positioning SCFAs as vital mediators connecting microbial metabolic alterations to neural plasticity. This research not only redefines the role of nutritional biochemistry in neuromodulation but also suggests the potential of microbial metabolite monitoring to tailor antidepressant therapies for enhanced efficacy. Show less

Different subtypes of dendritic cells (DCs) can induce different types of immune responses. Our previous study found that Echinococcus granulosus (E. granulosus) antigens (Eg.ferritin, Eg.mMDH and Eg.10) stimulated DC differentiation to different subtypes and produced different immune responses. To further understand whether Eg.ferritin, Eg.mMDH and Eg.10 affect the DC-mediated immune response by promoting the differentiation of monocytes to DCs. Bone marrow-derived monocytes were exposed to three antigens of E. granulosus on days 0, 3, 5, and 7. The percentage of monocyte-derived DCs (moDCs), DCs subsets, and the expression of surface molecules of DCs at different time points in different groups were assessed by flow cytometry. The levels of cytokines of IL-1β, IL-4, IL-6, IL-10, IL-13, IFN-γ, TNF-α, IL-12p70, IL-18, IL-23, and IL-27 in the cell culture supernatant were detected by multi-factorial detection technology. The percentage of moDCs revealed that none of the three antigens blocked monocyte differentiation to DCs. The monocytes of 7-day-old cultures showed increased sensitivity to these antigens. The Eg.ferritin induced more mature DCs, which expressed high levels of MHC II and costimulatory molecules, and secreted Th1 cytokines. Eg10 and Eg.mMDH induced lower degrees of DC maturation, however differentiated DCs were in a semi-mature state due to low expression of MHC II and costimulatory molecules and secretion of higher Th2 and lower Th1 cytokines. Eg.ferritin promotes full maturation of DCs and induces Th1 immune response, whereas Eg.10 and Eg.mMDH induce semi-mature DCs producing higher levels of Th2 cytokines. Show less