Electroacupuncture at Jiaji points regulates splenic immunity and gut microbiota to ameliorate peripheral immune dysfunction after spinal cord injury.

Peripheral immune dysfunction induced by spinal cord injury (SCI) is a key factor rendering patients prone to infection. However, there is still a lack of effective intervention methods for this pathological process. This study aims to explore the effects of electroacupuncture (EA) at Jiaji points on peripheral immune dysfunction induced by SCI in a mouse T10 SCI model. Following seven consecutive days of EA at T9 and T11, results showed that EA reversed SCI-induced splenic white pulp atrophy, CD3+ T cell reduction, and downregulation of inflammatory cytokines, indicating a systemic immunomodulatory effect. Concurrently, EA alleviated colonic mucosal inflammatory infiltration and barrier damage, and improved colonic emptying. These improvements in the intestinal environment were accompanied by specific modulation of key functional microbial genera, as well as alterations in microbial function and metabolic profiles, particularly in amino acid synthesis and bile acid metabolism. Furthermore, EA significantly upregulated the level of calcitonin gene-related peptide (CGRP) in the colon and significantly increased the gene expression of the bile acid receptor FXR in the colon of SCI mice. In the spleen, although the change in CGRP level did not reach statistical significance after EA intervention, an increasing trend was observed. These findings demonstrate that EA at Jiaji points may regulate the intestinal function-gut microbiota-bile acid synthesis/FXR signaling axis and synergistically restore splenic immune homeostasis to ameliorate peripheral immune dysfunction induced by SCI, with CGRP playing a potential neural signaling role in the processes.