Moxibustion alleviates depression-like behavior in rats with Crohn's disease by inhibiting the kynurenine pathway metabolism in the gut-brain axis.

Researchers investigated whether moxibustion, a traditional Chinese medicine therapy that uses burning herbs to warm acupuncture points, could help with depression that often accompanies Crohn's disease. The study used rats with experimentally-induced Crohn's disease and depression-like behaviors. Researchers applied moxibustion to specific acupuncture points including Tianshu (ST25, on both sides), Qihai (CV6), and Baihui (GV20). They compared moxibustion alone to moxibustion combined with a medication that blocks a specific enzyme involved in inflammation. The results showed that moxibustion significantly reduced both intestinal inflammation and depression-like behaviors in the rats. Testing revealed that moxibustion works by affecting the kynurenine pathway, a metabolic process that connects gut inflammation to brain function through what scientists call the "gut-brain axis." Specifically, moxibustion reduced inflammatory markers in both the intestine and the brain's hippocampus region, decreased harmful metabolites, and calmed overactive immune cells and neurons in the brain. Interestingly, adding the medication to moxibustion treatment didn't provide significant additional benefit, suggesting moxibustion alone was highly effective. For patients with inflammatory bowel disease experiencing depression, this research provides scientific evidence that moxibustion may offer a promising complementary treatment approach by addressing both gut inflammation and its effects on mood through interconnected biological pathways. If you're considering moxibustion for Crohn's disease-related depression, consult with a licensed acupuncturist trained in traditional Chinese medicine techniques.

This preclinical study examined moxibustion's mechanisms in treating depression comorbid with Crohn's disease using TNBS-induced rat models. Moxibustion was applied to ST25 (bilateral), CV6, and GV20, with comparison to moxibustion plus IDO1 inhibitor 1-MT. Outcomes measured included behavioral assessments (forced swimming test, sucrose preference test, open field test), Western blot analysis of IDO1, TNF-α, and IL-1β in colon and hippocampus, and GC-MS detection of kynurenine pathway metabolites. Results demonstrated significant reduction in colonic inflammation and depression-like behaviors. Moxibustion downregulated IDO1 and pro-inflammatory cytokines, decreased KYN/TRP ratio, increased KYNA/KYN and KYNA/QUIN ratios in hippocampus, and reduced Iba-1, c-fos expression, microglial activation, and neuronal hyperactivity. Adding 1-MT provided no significant additional benefit. Clinical takeaway: Moxibustion at ST25, CV6, and GV20 may effectively address IBD-related depression by modulating gut-brain axis kynurenine metabolism and suppressing neuroinflammation, offering a targeted treatment approach for this challenging comorbidity.