Effect of Zhuang-medicine medicated thread moxibustion on apoptosis-related protein expression in gastric smooth muscle tissue of diabetic gastroparesis rats based on ATF6/CHOP signaling pathway

ObjectiveTo observe the effect of Zhuang-medicine medicated thread moxibustion on endoplasmic reticulum stress-associated apoptotic proteins in rats with diabetic gastroparesis （DGP）， so as to explore its underlying therapeutic mechanisms.MethodsMale SD rats were randomly divided into five groups： blank control， DGP model， medication， non-meridian non-acupoint （non-acupoint） moxibustion， and Yangming meridian acupoint moxibustion groups， with 12 rats in each group. The DGP model was established by intraperitoneal injection of 2% streptozotocin （STZ， 55 mg/kg）. Rats of the medication group received gavage of mosapride citrate suspension （0.15 mg/mL）. For rats in the Yangming meridian acupoint moxibustion group， the medicated thread moxibustion was applied to bilateral “Liangmen” （ST21）， “Qichong” （ST30）， “Zusanli” （ST36） and “Fenglong” （ST40）， with three moxa cones for each acupoint. For rats of the non-acupoint group， the same medicated thread moxibustion was applied to the sites 2.5 mm or 5 mm away from the abovementioned Yangming meridian acupoints. The 3 intervention groups were conducted once daily for 3 weeks. The symptom scores were assessed. The blood glucose levels were measured using a blood glucose meter， and the gastric emptying rate was assessed by using phenol red gavage method. The apoptosis index of gastric smooth muscle cells was detected using TUNEL staining. The expression levels of glucose-regulated protein 78 （GRP78）， activating transcription factor 6 （ATF6）， and CCAAT/enhancer-binding protein homologous protein （CHOP） in the gastric antral smooth muscle were detected using Western blot， and the immunoactivities of B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and Caspase-12 in the gastric smooth muscle tissues were detected using immunohistochemistry method.ResultsCompared to the control group， rats in the model group exhibited a significant increase in the symptom score， blood glucose level， smooth muscle cell apoptosis index， and the expression levels of GRP78， ATF6， CHOP， Bax and Caspase-12 proteins （PPPPPPPPConclusionZhuang-medicine medicated thread moxibustion can ameliorate symptoms， promote gastric emptying and lower blood glucose in DPG rats， which may be related to its functions in regulating the expression of endoplasmic reticulum stress-associated apoptotic proteins， suppressing the expression of GRP78， ATF6， CHOP， Caspase-12， and Bax proteins （ATF6/CHOP signaling pathway） and upregulating the expression of Bcl-2 protein in the gastric antral smooth muscle.