Effect on glycemia in rats with type 2 diabetes induced by streptozotocin: low-frequency electro-pulse needling stimulated Weiwanxiashu (EX-B 3) and Zusanli (ST 36)

Abstract

OBJECTIVETo investigate the effect of low frequency electro-pulse acupuncture (EA) on blood glucose in rats with streptozotocin-induced type 2 diabetes, and the possible mechanism underlying the action. METHODSRat models were established with high fat feeding and intraperitoneal injection of streptozotocin (STZ) (30 mg/kg). Rats with a random blood glucose > 16.7 mmol/L and blood glucose at 2 h-point of oral glucose tolerance test (OGTT) > 11.1 mmol/L were included as diabetic rats, and randomly divided into model group, EA Weiwanxiashu (EX-B 3) group, EA Zusanli (ST 36) group, glimepiride group, and EA non-acupoint group (n = 12). EA (2 Hz continuous wave, 2 mA, 20 min/day, 6 days/week, 4 weeks) and intra-gastric administration of glimepiride were applied as interventions. With fasting blood glucose and OGTT tested at the end of the intervention, the study observed the patterns of hypoglycemic effects. For mechanism study, it observes hematoxylin and eosin staining and Masson staining of pancreas paraffin sections, protein expression of glucagon-like peptide 1 receptor (GLP-1R) in the pancreas and skeletal muscle, glucose transporter 4 (GLUT4) protein expression in skeletal muscle membrane, to detect whether EA controls blood glucose via regulation of GLP-1R. RESULTSEA Weiwanxiashu (EX-B 3) significantly increased model rats’ pancreas GLP-1R, and GLUT4 of skeletal muscle membrane; the therapy significantly decreased model rats’ skeletal muscle GLP-1R, restored pancreas morphology, and reduced fasting blood glucose and insulin resistance indices. CONCLUSIONEA Weiwanxiashu (EX-B 3) alone has significant effect on glycemia. EA Weiwanxiashu (EX-B 3) plus glimepiride further strengthen the effect. The regulation of the GLP-1R in pancreas and skeletal muscle might be mechanism underpinning the effect.