[Effect of acupuncture on serum inflammatory cytokines and intestinal flora in rats with stress-induced gastric ulcer].

OBJECTIVE: To investigate the effect of acupuncture on serum inflammatory cytokines and intestinal flora in rats with stress-induced gastric ulcer (SGU), and to explore the mechanism of acupuncture in the treatment of SGU. METHODS: Sprague-Dawley rats were randomly divided into blank, model, acupuncture, and medication groups, with 7 rats in each group. Restraint water-immersion stress was used to establish the model of SGU. The rats in the acupuncture group were given acupuncture at "Zhongwan"(CV12) and bilateral "Zusanli"(ST36) for 20 min, once a day for 5 days, and those in the medication group were given 2 mL solution of Omeprazole enteric-coated tablets (0.2 mg/kg) by gavage, once a day for 5 days. The Guth method was used to calculate the gastric mucosa damage index, HE staining was used to observe the histopathological changes of the gastric mucosa, ELISA was used to measure the serum levels of interleukin-4 (IL-4) and interleukin-6 (IL-6), and 16S rDNA sequencing method was used to observe the change in intestinal flora. RESULTS: Compared with the blank group, the model group had a significant increase in gastric mucosa damage index (P<0.01), markedly pathological changes of the gastric mucosa shown by HE staining, a significant reduction in the content of serum IL-4 (P<0.01), and a significant increase in the content of serum IL-6 (P<0.01), as well as a significant reduction in Bacteroidetes and Firmicutes at the phylum level. Compared with the model group, the acupuncture group and the medication group had a significant reduction in gastric mucosa damage index (P<0.01, P<0.05). HE staining showed reduced pathological changes of the gastric mucosa, as well as a significant increase in the content of serum IL-4 (P<0.01, P<0.05) and a significant reduction in the content of serum IL-6 (P<0.01, P<0.05). As for the intestinal flora, there was a significant increase in Bacteroidetes. Compared with the medication group, the gastric mucosa damage index was decreased （P<0.05），the content of serum IL-4 was significantly increased （P<0.05）, while the content of serum IL-6 significantly decreased (P<0.05) in the acupuncture group. CONCLUSION: Acupuncture at CV12 and ST36 can down-regulate the content of serum IL-6, up-regulate the content of serum IL-4, maintain the relative homeostasis of inflammatory cytokines, and regulate the community structure of intestinal flora, and thus help to repair the damage of gastric mucosa.