Effects of electroacupuncture stimulation at different spinal segmental levels in a rat model of diabetes mellitus.

BACKGROUND: Diabetes mellitus (DM) is associated with high morbidity, mortality and economic cost. Studies have shown that acupuncture can improve many symptoms of DM. OBJECTIVES: To examine for differences in effects of electroacupuncture (EA) stimulation at Weiwanxiashu, BL15 and BL23 in the streptozotocin (STZ)-induced DM rat model, to help guide clinical selection of acupuncture points. METHODS: 90 male rats weighing 160±5 g were used. 12 rats were control fed (Normal group) and 78 were fed a high-fat high-sugar diet for 8 weeks and underwent intraperitoneal STZ injection to model DM. 60 animals that met modelling criteria were randomly divided into an untreated DM group and four groups receiving EA at Weiwanxiashu (DM+WWX group), BL15 (DM+BL15 group), BL23 (DM+BL23 group) or a non-traditional acupuncture point on the tail (DM+Tail group). Fasting blood glucose, total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and insulin levels were determined and an oral glucose tolerance test (OGTT) performed. RESULTS: EA at Weiwanxiashu had a glucose-lowering effect on the 21st and 28th days, decreased TC, TG and LDL-C levels, increase insulin levels and improved glucose tolerance. EA at BL15 had a glucose-lowering effect on the7th, 14th and 21st days of intervention but did not impact lipids, insulin or OGTT parameters. EA at BL23 or on the tail had no significant effects. CONCLUSION: EA at Weiwanxiashu and BL15 had differential effects on metabolic markers in the STZ-induced rat model of DM. These effects may be explained neuroanatomically by variations in the segmental innervation of the tissues at these locations.

[Effect of Electroacupuncture at "Weiwanxiashu" (EX-B 3) on Islet Morphology and the Expression of Pancreatic Glucagon-like Peptide-1 Receptor in Type 2 Diabetes Rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on pancreatic glucagon-like peptide-1 receptor (GLP-1 R), pancreatic and duodenal homeobox 1 (PDX-1) protein expression and blood glucose in type 2 diabetes rats, so as to explore the underlying mechanism of EA treatment in improving type 2 diabetes. METHODS: Sprague-Dawley rats were randomly divided into blank control group, model group, "Weiwanxiashu" (EX-B 3) group, "Xinshu" (BL 15) group, and "Shenshu" (BL 23) group, 12 rats in each group. Diabetes model was established by feeding the rat with high fat and high sugar diet combined with intraperitoneal injection of streptozotocin (35 mg/kg). All the EA groups received 2 Hz, 2 mA continuous wave treatment for 20 min everyday, 6 times per week lasting for 4 weeks. Fasting blood glucose was measured by Roche glucometer before and after treatment. Hematoxylin and eosin (HE) staining and Masson staining were used to detect pancreas morphology. GLP-1 R and PDX-1 protein expressions in the pancreas were detected by Western blot. RESULTS: Compared to the blank control group, fasting blood glucose was significantly increased in the model group(P<0.01), accompanied with shrunken islet area, reduced nucleus counts of islet ß cells, and compensatorily enlarged ß cell nucleus. Compared to the model group, EA intervention significantly reduced fasting blood glucose level only in the EX-B 3 group (P<0.05), partly restored pancreas morphology and nucleus counts of islet ß cells in the EX-B 3, BL 15, and BL 23 groups. Compared to the blank control group, GLP-1 R and PDX-1 expressions were decreased in the model group (P<0.01), while EA treatment could obviously increase GLP-1 R expression in the EX-B 3(P<0.01), BL 15 (P<0.01) and BL 23 (P<0.05) groups compared with the model group. The expression of GLP-1 R in the BL 15 group was the highest among the three EA groups (P<0.05,P<0.01), and that in the EX-B 3 group was higher than in the BL 23 group (P<0.05).There were no signifincant differences in the expression of PDX-1 protein among the three EA groups (P>0.05). CONCLUSIONS: EA treatment at EX-B 3 can reduce blood glucose via regulating pancreas function, increasing pancreatic GLP-1 R expression, and partly restoring the morphology of pancreas.

PI3K-GLUT4 Signal Pathway Associated with Effects of EX-B3 Electroacupuncture on Hyperglycemia and Insulin Resistance of T2DM Rats.

Objectives. To explore electroacupuncture's (EA's) effects on fasting blood glucose (FBG) and insulin resistance of type 2 diabetic mellitus (T2DM) model rats and give a possible explanation for the effects. Method. It takes high fat diet and intraperitoneal injection of streptozotocin (STZ, 30 mg/kg) for model preparation. Model rats were randomly divided into T2DM Model group, EA weiwanxiashu (EX-B3) group, and sham EA group (n = 12/group). EA (2 Hz continuous wave, 2 mA, 20 min/day, 6 days/week, 4 weeks) was applied as intervention. FBG, area under curve (AUC) of oral glucose tolerance test (OGTT), insulin resistance index (HOMA-IR), pancreatic B cell function index (HOMA-B), skeletal muscle phosphorylated phosphatidylinositol-3-kinase (PI3K), glucose transporter 4 (GLUT4), and membrane GLUT4 protein expression were measured. Results. EA weiwanxiashu (EX-B3) can greatly upregulate model rat's significantly reduced skeletal muscle PI3K (Y607) and membrane GLUT4 protein expression (P < 0.01), effectively reducing model rats' FBG and AUC of OGTT (P < 0.01). The effects are far superior to sham EA group. Conclusion. EA weiwanxiashu (EX-B3) can upregulate skeletal muscle phosphorylated PI3K protein expression, to stimulate membrane translocation of GLUT4 and thereby increase skeletal muscle glucose intake to treat T2DM.