Effect of moxibustion at "Zusanli" (ST 36) and "Shenshu" (BL 23) on intestinal flora in adjuvant arthritis rats

Abstract

To observe the effect of moxibustion at "Zusanli" (ST 36) and "Shenshu" (BL 23) on inflammatory factors and intestinal flora in the rats with adjuvant arthritis. A total of 36 Wistar rats were randomized into a normal group, a model group and a moxibustion group, 12 rats in each one. In the model group and the moxibustion group, the adjuvant arthritis model was established by a compound method, including the environmental factors, i.e. wind, cold and damp, and Freund's complete adjuvant. In the moxibustion group, moxibustion intervention was exerted at "Zusanli" (ST 36) and "Shenshu" (BL 23), for 20 min at each acupoint, once daily, consecutively for 21 days. The paw swelling degree and arthritis index (AI) score were observed before and after intervention in the rats of each group. Using real-time fluorescence quantitative PCR method (real-time PCR) and Western blot method, the mRNA and protein expressions of inflammatory factors of colon tissue, i.e. interleukin (IL) 1β, tumor necrosis factor-α (TNF-α), IL-6, were detected after intervention in the rats of each group. The intestinal flora was detected with 16SrRNA sequencing technology after intervention in the rats of each group. Compared with the normal group, the paw swelling degree and AI score were increased in the rats of the model group (P<0.05); after intervention, compared with the model group, the paw swelling degree and AI score were reduced in the rats of the moxibustion group (P<0.05). Compared with the normal group, the expressions of IL-1β, TNF-α and IL-6 mRNA, as well as proteins were increased in the colon tissue of the rats in the model group (P<0.05); compared with the model group, the expressions of IL-1β, TNF-α and IL-6 mRNA, as well as proteins were reduced in the colon tissue of the rats in the moxibustion group (P<0.05). Compared with the normal group, OTUs count was reduced in the rats of the model group (P<0.05); and compared with the model group, OTUs count was increased in the rats of the moxibustion group (P<0.05). Compared with the normal group, Simpson index was increased, Chao1 and Ace were reduced in the rats of the model group (P<0.05); while, compared with the model group, Chao1 and Ace were increased in the rats of the moxibustion group (P<0.05). Compared with the normal group, the relative abundance of uncategorized Clostridium, Lactobacillus, Prevotella, uncategorized Porphyromonadaceae and uncategorized Prevotella was increased (P<0.05), and the relative abundance of uncategorized Spironella was reduced in the model group (P<0.05). While, compared with the model group, the relative abundance of uncategorized Clostridium, Lactobacillus, uncategorized Prevotella was reduced in the moxibustion group (P<0.05) and that of uncategorized Spironella was increased (P<0.05). Moxibustion at "Zusanli" (ST 36) and "Shenshu" (BL 23) relieves the joint symptoms of adjuvant arthritis rats and inhibits the expressions of inflammatory factors, which is probably related to the regulation of the structure of intestinal flora.