Electroacupuncture may improve insulin resistance and attenuate endothelial dysfunction. - GreenMedInfo Summary

OBJECTIVE: To investigate the effect of electroacupuncture (EA) on endothelial dysfunction related to high fat diet (HFD)-induced insulin resistance through the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) signalling pathway.

METHODS: Twenty-four male Sprague-Dawley rats were fed a regular diet (Control group, n=8) or a HFD (n=16) for 12 weeks to induce an insulin resistance model. HFD-fed rats were divided into two groups that remained untreated (HFD group, n=8) or received electroacupuncture (HFD+EA group, n=8). EA was applied at PC6, ST36, SP6 and BL23. At the end of the experiment, fasting blood glucose (FBG), serum insulin (FINS), serum C-peptide (C-P) and homeostatic model assessment of insulin resistance (HOMA-IR) indices were determined. Pancreatic islet samples were subjected to histopathological examination. The thoracic aorta was immunostained with anti-rat insulin receptor substrate (IRS)-1, Akt and endothelial nitric oxide synthase (eNOS) antibodies. mRNA and protein expression of IRS-1, PI3K, Akt2 and eNOS in the vascular endothelium were determined by real-time PCR and Western blot analysis, respectively.

RESULTS: The bodyweight increase of the HFD+EA group was smaller than that of the untreated HFD group. Compared with the HFD group, the levels of FBG, FINS, C-P and HOMA-IR in the HFD+EA group decreased significantly (P<0.01). Histopathological evaluation indicated that EA improved pancreatic islet inflammation. The expression of endothelial markers, such as IRS-1, PI3K, Akt2 and eNOS, decreased in the HFD group, while EA treatment appeared to ameliorate the negative impact of diet.

CONCLUSION: EA may improve insulin resistance and attenuate endothelial dysfunction, and therefore could play a potential role in the prevention or treatment of diabetic complications and cardiovascular disease through the PI3K/Akt signalling pathway.