Study on the regulatory effect of herbal cake-partitioned moxibustion on colonic CD206, AMPK and TSC2 in rats with Crohn disease

Objective To explore the mechanism of herbal cake-partitioned moxibustion in Crohn disease (CD) treatment by observing the effect of herbal cake-partitioned moxibustion on protein expressions of colonic M2 macrophage marker CD206, AMP-activated protein kinase (AMPK) and tuberous sclerosis complex (TSC) 2. Methods Twenty-six specific pathogen free male rats were randomly divided into a normal group, a model group and a herbal cake-partitioned moxibustion group. The CD model was prepared by enema with the mixture of 5% (W/V) 2,4,6-trinitrobenzene sulfonic acid (TNBS) and 50% ethanol at 2:1 (volume ratio). After the model was successfully prepared, rats in the herbal cake-partitioned moxibustion group received herbal cake-partitioned moxibustion at Qihai (CV 6) and bilateral Tianshu (ST 25). Hematoxylin-eosin (HE) staining was used to observe the histopathological changes of rat colon; immunohistochemical technique was used to detect the expression of colonic CD206 protein; Western blot, immunofluorescence, and real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) technologies were used to detect the protein and mRNA expressions of colonic AMPK and TSC2. Results Compared with the normal group, rats in the model group showed damaged colonic mucosa, missing of the epithelial layer, thickened submucosa, vascular proliferation, massive infiltration of monocytes and lymphocytes, and cracked ulcers that reached the muscle layer. Rats in the herbal cake-partitioned moxibustion group showed reduced intestinal inflammation and healing intestinal epithelium ulcers. Compared with the normal group, rat colonic CD206 protein expression, and the protein and mRNA expressions of colonic AMPK and TSC2 were decreased in the model group (all P<0.01); compared with the model group, rat colonic CD206 protein expression was increased (P<0.01), as well as the protein and mRNA expressions of AMPK and TSC2 in the herbal cake-partitioned moxibustion (all P<0.05). Conclusion Herbal cake-partitioned moxibustion can reduce intestinal inflammation in CD rats, increase colonic CD206 protein expression, and up-regulate the protein and mRNA expressions of colonic AMPK and TSC2.