ABSTRACT
Objective: To explore the potential mechanism of acupuncture and moxibustion in treating Crohn disease (CD) by evaluating the changes in histamine and inflammatory factors in the skin tissue at Tianshu (ST25) of rats.Methods: Fifty-eight Sprague-Dawley rats were randomly divided into a normal group (n=14) and a CD-modeling group (n=44). Rats in the CD-modeling group received enema with 2,4,6-trinitrobenzene sulfonic acid plus ethanol to establish CD models. The enema was repeated once every 7 d for a total of 4 times. After modeling, four modeled rats and four normal rats were randomly selected for model identification. After the CD model was successfully established, the remaining rats in the CD-modeling group were randomly divided into a model group, an acupuncture group, a moxibustion group, and a Western medication group, with ten rats in each group. The rats in the acupuncture and moxibustion groups were treated with acupuncture or moxibustion at Tianshu (ST25) and Shangjuxu (ST37); the rats in the Western medication group were treated with mesalazine enteric-coated tablets by gavage for continuous 7 d. After the intervention, the colon tissue of rats in each group was collected. After gross observation, hematoxylin-eosin (HE) staining was performed to further observe the pathological changes. The expression of histamine in the skin tissue at Tianshu (ST25) was detected by enzyme-linked immunosorbent assay. The expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-18, IL-10, and IL-6 in the skin tissue at Tianshu (ST25) was detected by Western blotting. Results: Compared with the normal group, the colonic wall of rats in the model group showed cobblestone-like changes, local ulcers, and polyps in dark red and thickening and hardening. HE staining showed local loss of mucosal epithelial layer and formation of slit-like ulcers, destruction of mucosal glands, edema, and infiltration of inflammatory cells in lamina propria and submucosa, and occasional formation of sarcoid-like granuloma. The levels of histamine and IL-6 were significantly up-regulated (P<0.01, P<0.05), and the levels of TNF-α, IL-18, and IL-10 were significantly down- regulated (P<0.01 or P<0.05) in the skin tissue at Tianshu (ST25) of rats in the model group. Compared with the model group, the pathomorphological damage of the colon tissue of rats in the acupuncture group, moxibustion group, and Western medication group was significantly improved. The levels of histamine and IL-6 were significantly down- regulated (P<0.01, P<0.05), and the level of IL-10 was significantly up-regulated (P<0.01) in the skin at Tianshu (ST25) of rats in the acupuncture group. The levels of histamine and IL-6 were significantly down-regulated (P<0.01, P<0.05), and the levels of TNF-α, IL-18, and IL-10 were significantly up-regulated (P<0.01 or P<0.05) in the skin tissue at Tianshu (ST25) of rats in the moxibustion group. The level of histamine was significantly down-regulated (P<0.01), and the levels of IL-18 and IL-10 were significantly up-regulated (P<0.05, P<0.01) in the skin tissue of rats in the Western medication group. Compared with the acupuncture group, the level of IL-10 in the skin tissue at Tianshu (ST25) of rats in the moxibustion group was significantly up-regulated (P<0.01). Conclusion: The inflammatory responses in the skin tissue at Tianshu (ST25) may be the external manifestation of CD. Significant differences in the regulation of inflammatory responses in the skin tissue at Tianshu (ST25) between acupuncture and moxibustion exist, which may be caused by the differences in the stimulation characteristics between acupuncture and moxibustion.