ABSTRACT
Objective:To study the mechanism of Taoren Chengqitang in regulating intestinal myoelectric activity and microenvironment homeostasis in intestinal sepsis rats based on high mobility group protein 1(HMGB1)/Toll-like receptor 4(TLR4)/nuclear factor -κB(NF-κB) pathway. Method:The 60 SD rats were randomly divided into sham operation group, model group, glycyrrhizic acid (HMGB1 inhibitor, 0.03 g·kg-1) group, Taoren Chengqitang group (10 g·kg-1), glycyrrhizic acid+Taoren Chengqitang group (0.03 g·kg-1+10 g·kg-1), with 12 rats in each group. Except the sham operation group, the other groups established intestinal sepsis rat models, each group was treated with medicine, hematoxylin-eosin (HE) staining was used to detect the histopathological changes of small intestinal mucosa in rats of each group, the changes of mucosal thickness and villus height were compared, the levels of secretory immunoglobulin A (sIgA), diamine oxidase (DAO) and D-lactic acid in intestinal mucosa of rats were detected by kit, the intestinal myoelectrical activity of rats in each group was measured, the slow wave frequency and amplitude of small intestinal smooth muscle were compared, the intestinal flora of rats in each group was detected, the contents of E. coli, Bifidobacterium and Lactobacillus were compared, and the expressions of HMGB1/TLR4/NF-κB pathway proteins HMGB1, TLR4, MyD88 and NF-κB p65 in small intestinal tissues were detected by Western blot. Result:Compared with sham operated group, the villus height, mucosal thickness, sIgA content, slow wave frequency and amplitude of smooth muscle, Bifidobacterium and Lactobacillus contents in intestinal mucosa of model group rats were significantly decreased, and serum DAO and D-lactic acid levels, intestinal E. coli content, intestinal tissue HMGB1, TLR4, MyD88 and NF-κB p65 proteins were significantly increased (P<0.05). Compared with the model group, the villus height, mucosal thickness, sIgA content, slow wave frequency and amplitude of smooth muscle, Bifidobacterium and Lactobacillus contents in intestinal mucosa of the Taoren Chengqitang group, glycyrrhizic acid group, and glycyrrhizic acid + Taoren Chengqitang group were significantly increased, and serum DAO and D-lactic acid levels, intestinal E. coli content, intestinal tissue HMGB1, TLR4, MyD88 and NF-κB p65 proteins were significantly decreased (P<0.05). Compared with the Taoren Chengqitang group and the glycyrrhizic acid group, the villus height, mucosal thickness, sIgA content, slow wave frequency and amplitude of smooth muscle, Bifidobacterium and Lactobacillus contents in intestinal mucosa of glycyrrhizic acid+Taoren Chengqitang group were significantly increased, and serum DAO and D-lactic acid levels, intestinal E. coli content, intestinal tissue HMGB1, TLR4, MyD88 and NF-κB p65 proteins were significantly decreased, the differences were statistically significant (P<0.05). Conclusions:Taoren Chengqitang can alleviate intestinal mucosal injury, regulate intestinal myoelectrical activity and microenvironment homeostasis, restore intestinal function and maintain flora balance in intestinal sepsis rats, which may be achieved by down-regulating HMGB1/TLR4/NF-κB pathway.
ABSTRACT
<p><b>OBJECTIVE</b>To observe the influence of electroacupuncture (EA) at lower-sea points of stomach, large intestine, small intestine and gallbladder on interleukin-1β (IL-1β), high mobility group protein 1 (HMGB 1) and alpha 7 nicotinic acetylcholine receptor (nAchR α7) in rats with acute gastric mucosal lesion (AGML), so as to explore whether there is relative specificity in treating gastric viscera disease by stimulating Zusanli (ST 36).</p><p><b>METHODS</b>Sixty healthy SD rats were randomly assigned into a blank group, a model group, a Zusanli group, a Shangjuxu group, a Xiajuxu group and a Yanglingquan group, ten rats in each one (half male and half female). The WRS method was applied to induce the AGML model except the rats in the blank group. The rats in the blank group were treated with routine diet; the rats in the model group were treated with immobilization at rat platform, 30 min per time; the rats in the Zusanli group, Shangjuxu group, Xiajuxu group and Yanglingquan group were treated with acupuncture and connected with EA device (dilatational wave 10 Hz/50 Hz, positive electrode on the left side and negative electrode on the right side, intensity was appropriate when rat hind leg slightly shook), 30 min per time. The treatment was given once a day. After consecutive 10-day treatment, the gastric tissue was collected and the damage of gastric mucosa was evaluated; ELISA method was applied to measure the content of serum IL-1β and tissue HMGB 1; the Western blot method was applied to measure the expression of nAchR α7 receptor.</p><p><b>RESULTS</b>(1) Compared with the model group, the ulcer index (UI) of gastric mucosa, serum IL-1β and tissue HMGB 1 were lower, and the expression of nAchR α7 was increased in the remaining groups (<0.05,<0.01). (2) Compared with the Zusanli group, the UI of gastric tissue, serum IL-1β and tissue HMGB 1 were higher in the Shangjuxu group, Xiajuxu group and Yanglingquan group (<0.05,<0.01), and the expression of nAchRα7 was reduced in the Yanglingquan group (<0.01).</p><p><b>CONCLUSIONS</b>(1) EA at digestive system-related lower-sea points, through IL-1β, HMGB 1 and nAchR α7, could regulate immune response, lighten inflammatory reaction and reduce mucosal injury, which could realize the intervention effect on AGML rats. (2) From the comparison, it is concluded the intervention effect of Zusanli group is superior to the other groups, partly indicating the relative specificity between Zusanli and stomach.</p>