Long-term tuina can inhibit the occurrence of gastroparesis by protecting gastrointestinal function in diabetic rats

Jian-Zhen Jiang^*Wanqiu LiKun-Lin KuangYu-Qing JiangZhao-Xuan HeLi-Juan ZhangJingya CaoDan WangXinyue ZhangZilei TianJun Zhu^*Dezhong Peng^*

• College of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan Province, China

Background: Diabetic gastroparesis (DGP) is a common complication in the later stage of Diabetes mellitus (DM). To investigate the protective effect of long-term tuina on GI function and the occurrence of DGP in diabetic rats.Methods: 20 healthy male SD rats were randomly divided into four groups: NC, DM, DM + GT, and DM + TT. DM was induced with streptozotocin and a high-fat, high-sugar diet for 6 weeks. The DM + TT group received tuina therapy (20 min/session, 5 times/week) for 6 weeks. Weekly random blood glucose, gastric emptying rate, and small intestinal propulsion rate were measured. HE staining assessed gastric antrum and ileum pathology. Ca 2+ -Mg 2+ -ATPase and CS activities, and nNOS, CaM, and MLCK mRNA and protein expressions were evaluated by PCR and Western blot. 5-HT content was measured by ELISA. Piezo2 and 5-HT4R expressions were analyzed by immunofluorescence staining to observe tuina's protective effect on GI function in DM rats.Results: Random blood glucose measurements showed normal levels in the NC group, while other groups remained above 16.7 mmol/L. The DM group exhibited reduced gastric emptying and small intestinal propulsion rates, along with gastric antrum and ileum damage.The DM + TT group showed significant improvements in gastric emptying and intestinal propulsion rates, and reduced tissue damage compared to the DM group. In the DM + TT group, mRNA and protein expressions of CaM and MLCK in antrum tissue, and nNOS, CaM, and MLCK in ileum tissue, were significantly increased. Activities of Ca 2+ -Mg 2+ -ATPase and CS enzymes in ileum tissue were also elevated, indicating enhanced gastrointestinal function.Further analysis showed increased mRNA expressions of Piezo2 and 5-HT4R, and protein expressions of Piezo2, 5-HT, and 5-HT4R in the ileum tissues of the DM + TT group.Immunofluorescence intensity of Piezo2 and 5-HT in the ileum was also heightened. These results suggest that tuina's protective effect on gastrointestinal function is related to the expression of Piezo2 ion channels.3 Conclusions: Long-term tuina protects the GI function of DM rats and inhibits the occurrence of DGP, which might be related to Piezo2/5-HT pathway.