Intense electroacupuncture normalizes insulin sensitivity, increases muscle GLUT4 content, and improves lipid profile in a rat model of polycystic ovary syndrome
Julia Johansson, Yi Feng, Ruijin Shao, Malin Lönn, Håkan Billig, Elisabet Stener-Victorin
American Journal of Physiology. Endocrinology and Metabolism
Intense electroacupuncture normalizes insulin sensitivity, increases muscle GLUT4 content, and improves lipid profile in a rat model of polycystic ovary syndrome. Polycystic ovary syndrome (PCOS) is associated with hyperandrogenism and insulin resistance, possibly reflecting defects in skeletal muscle and adipocyte insulin signaling. Low-frequency (2 Hz) electroacupuncture (EA) increases insulin sensitivity in female rats with dihydrotestosterone (DHT)-induced PCOS, but the mechanism is
... We hypothesized that low-frequency EA regulates mediators involved in skeletal muscle glucose uptake and metabolism and alters the lipid profile in rats with DHT-induced PCOS. To test this hypothesis, we implanted in prepubescent female rats 90-day continuousrelease pellets containing DHT (PCOS). At 70 days of age, the rats were randomly subdivided into two groups: one received lowfrequency EA (evoking muscle twitches) for 20 -25 min five times/wk for 4 -5 wk; the other did not. Controls were implanted with pellets containing vehicle only. All three groups were otherwise handled similarly. Lipid profile was measured in fasting blood samples. Insulin sensitivity was determined by euglycemic hyperinsulinemic clamp, soleus muscle protein expression of glucose transporter 4 (GLUT4), and phosphorylated and nonphosphorylated Akt, and Akt substrate of 160 kDa was determined by Western blot analysis and GLUT4 location by immunofluorescence staining. PCOS EA rats had normalized insulin sensitivity, lower levels of total high-density lipoprotein and low-density lipoprotein cholesterol, and increased expression of GLUT4 in different compartments of skeletal muscle compared with PCOS rats. Total weight and body composition did not differ in the groups. Thus, in rats with DHT-induced PCOS, low-frequency EA has systemic and local effects involving intracellular signaling pathways in muscle that may, at least in part, account for the marked improved insulin sensitivity. acupuncture; glucose transporter 4; insulin resistance; muscle contraction; skeletal muscle HYPERANDROGENEMIA IS THE MOST PROMINENT endocrine phenotype in women with polycystic ovary syndrome (PCOS) (56) in addition to ovulatory dysfunction and polycystic ovary morphology (3). The main metabolic phenotype is hyperinsulin-Address for reprint requests and other correspondence: E.