title: Electroacupuncture plus metformin lowers glucose levels and facilitates insulin sensitivity by activating MAPK in steroid-induced insulin-resistant rats.
abstract: BACKGROUND
  Type 2 diabetes mellitus is the predominant form of diabetes. Although metformin is the preferred first-line drug for treatment of the disease, it is associated with a risk of secondary failure. Electroacupuncture (EA) can enhance insulin sensitivity and reduce blood glucose levels.
  
  
  OBJECTIVE
  To examine, in an animal study, whether EA combined with metformin (EA-metformin) results in a better glucose-lowering effect and greater insulin sensitivity than metformin alone in steroid-induced insulin-resistant rats.
  
  
  METHODS
  Adult Wistar rats were injected with dexamethasone to induce diabetes and subsequently treated with EA plus metformin or metformin alone. Variations in plasma glucose, plasma insulin, and plasma free fatty acid levels were studied at the midpoint and end of the experimental course. Insulin receptor substrate 1 (IRS-1) and peroxisome proliferator-activated receptor γ (PPAR-γ), which are associated with glucose transporter type 4 (GLUT4) translocation, and mitogen-activated protein kinase (MAPK), which is related to GLUT4 activation, were measured after EA treatment.
  
  
  RESULTS
  We found that EA-metformin resulted in a better glucose-lowering effect, greater insulin sensitivity, lower plasma free fatty acid levels and higher levels of MAPK than metformin alone (p<0.05). There were no significant differences between treatment groups in expression of IRS-1 or PPAR-γ.
  
  
  CONCLUSIONS
  The glucose-lowering effect and increased insulin sensitivity associated with EA-metformin administration is governed, at least in part, by its ability to stimulate the activation of GLUT4 via upregulation of MAPK expression.
authors.affiliation: Department of Acupuncture, China Medical University Hospital, Taichung, Taiwan School of Chinese Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Hsien-Yin
authors.initials: HY
authors.lastname: Liao
authors.affiliation: Department of Acupuncture, China Medical University Hospital, Taichung, Taiwan School of Chinese Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Mao-Feng
authors.initials: MF
authors.lastname: Sun
authors.affiliation: School of Chinese Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Jaung-Geng
authors.initials: JG
authors.lastname: Lin
authors.affiliation: School of Chinese Medicine, China Medical University, Taichung, Taiwan Department of Medicinal Botanicals and Health Applications, Da-Yeh University, Changhua, Taiwan.
authors.forename: Shih-Liang
authors.initials: SL
authors.lastname: Chang
authors.affiliation: Department of Acupuncture, China Medical University Hospital, Taichung, Taiwan Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan.
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Lee
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D003131:Combined Modality Therapy; D003907:Dexamethasone; D003924:Diabetes Mellitus, Type 2 / Q000139:chemically induced / Q000628:therapy*; D004195:Disease Models, Animal; D015671:Electroacupuncture; D004789:Enzyme Activation; D005230:Fatty Acids, Nonesterified / Q000097:blood; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D008687:Metformin / Q000494:pharmacology*; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007004:Hypoglycemic Agents; D007328:Insulin; D003907:Dexamethasone; D008687:Metformin; D020929:Mitogen-Activated Protein Kinase Kinases
keywords: ENDOCRINOLOGY