[Effect of electroacupuncture on silent information regulator 1, fork head transcription factor O1 and proopiomelanocortin in the hypothalamus of rats with obesity induced by high-fat diet].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) on silent information regulator 1 (SIRT1), forkhead transcription factor O1 (FoxO1), and proopiomelanocortin (POMC) in the hypothalamus of rats with high-fat diet-induced obesity (DIO), as well as the mechanism of EA in regulating central appetite peptides to help lose weight. METHODS: Male Wistar rats were randomly divided into normal group, model group, EA group, EA＋inhibitor group, inhibitor group, and sham-operation group, with 10 rats in each group. High-fat diet was used to establish a rat model of DIO. The rats in the EA group and EA＋inhibitor group were given EA at "Fenglong" (ST40), "Zhongwan "(CV12)，"Guanyuan "(CV4), and"Zusanli" (ST36) with continuous wave at a frequency of 2 Hz and an intensity of 1 mA, for 10 minutes each time. The rats in the EA＋inhibitor group and inhibitor group were given tube placement in the third ventricle and injection of the specific SIRT1 antagonist EX-527. The rats in the sham-operation group were given tube placement in the third ventricle and injection of artificial cerebrospinal fluid. The above treatment was given 3 times a week for 8 weeks in total. Body weight, food intake, and Lee's index were observed before and after treatment. An automatic biochemical analyzer was used to measure the serum levels of total cholesterol (TC), triglyceride (TG), and free fatty acid (FFA), and Western blot was used to measure the protein expression of SIRT1, FoxO1, acetylated FoxO1(AC-FoxO1), and POMC in the hypothalamus. RESULTS: Before treatment, the model group, the EA group, the EA＋inhibitor group, the inhibitor group, and the sham-operation group had significantly higher body weight and food intake than the normal group (P<0.01), and the model group and the sham-operation group had a significantly higher Lee's index than the normal group (P<0.05). Compared with the model group after treatment, the EA group and the EA＋inhibitor group had significant reductions in body weight, food intake, TC, and the protein expression of AC-FoxO1 (P<0.01, P<0.05) and significant increases in the protein expression of SIRT1, FoxO1 and POMC (P<0.01, P<0.05); the EA group had significant reductions in Lee's index and the levels of TG, FFA(P<0.05，P<0.01)；the inhibitor group had significant increases in food intake, the serum levels of TC, TG, FFA(P<0.01) and significant reductions in the protein expression of SIRT1, FoxO1 and POMC (P<0.01，P<0.05). Compared with the EA group, the EA＋inhibitor group and the inhibitor group had significant increases in body weight, food intake, Lee's index, the levels of TG, FFA and the protein expression of AC-FoxO1 (P<0.01, P<0.05) and significant reductions in the protein expression of SIRT1, FoxO1 and POMC (P<0.01); the inhibitor group had significant increases in the serum levels of TC (P<0.01). Compared with the EA＋inhibitor group, the inhibitor group had significant increases in body weight, food intake, the serum levels of TC, TG, FFA, and the protein expression of AC-FoxO1 (P<0.01), as well as significant reductions in the protein expression of SIRT1, FoxO1 and POMC (P<0.01). CONCLUSION: In rats with DIO, EA can effectively up-regulate the expression of SIRT1 in the hypothalamus, exert a deacetylation effect on FoxO1, and promote the expression of the downstream appetite-inhibiting peptide POMC, which may be one of the mechanisms of EA to help lose weight by regulating central appetite peptides in the obesity model.

[Electroacupuncture improves inflammatory reaction and insulin sensitivity in insulin-resistant obese rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on inflammatory reaction and insulin sensitivity in insulin-resistant obese (OIR) rats. METHODS: Thirteen male Wistar rats were randomly selected as the control group and fed with common diet. The other 39 rats were fed with high-fat diet for 8 weeks to establish OIR model and then randomized into model, EA and sham EA groups. EA (2 Hz, 1 mA) was applied to unilateral "Zusanli" (ST36), "Fenglong" (ST40), "Zhongwan" (CV12) and "Guanyuan" (CV4) for 15 min, once every other day for 8 weeks, and sham EA was applied to unilateral 4 control spots about 5 mm lateral to the aforementioned 4 acupoints after shallowly inserting acupuncture needles, but without electric current output. After 8 weeks' intervention, the body weight was recorded and the glucose infusion rate (GIR) measured using hyperinsulinemic-euglycemic clamp technique. At the 6th week of intervention, glucose contents of intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tole-rance test (IPITT) were measured. The levels of serum insulin (INS) and inflammatory factors as C-reactive protein (CRP), IL-6 and TNF-α were measured by using ELISA at the end of the treatment. The expression levels of IL-6, TNF-α, monocyte chemoattractant protein-1(MCP-1), IL-10 and IL-1ß proteins and mRNAs in the abdominal adipose tissues were detected by Western blot and quantitative real time-PCR, separately. The CD68 expression (displaying infiltration of macrophages) of adipose tissue was detected using immunohistochemistry. RESULTS: After modeling, the contents of glucose of IPGTT at 30, 60 and 120 min and those of IPITT at 15, 30, 60 and 120 min, serum INS, CRP, IL-6 and TNF-α, as well as the expression levels of IL-6, TNF-α, IL-1ß and MCP-1 proteins and mRNAs and CD68 protein were significantly increased (P<0.01, P<0.05), while the levels of GIR and IL-10 protein and mRNA were obviously decreased in the model group in comparison with those of the control group (P<0.01), suggesting an increase of inflammation and a decline of INS sensitivity. Following the interventions, the increased contents of glucose of IPGTT and IPITT, serum INS, CRP, IL-6 and TNF-α, expression levels of IL-6, TNF-α, IL-1ß and MCP-1 proteins and mRNAs and CD68 protein, and the decreased levels of GIR and IL-10 protein and mRNA were evidently reversed in the EA group compared with the model group (P<0.01, P<0.05) rather than those in the sham EA group (P>0.05). CONCLUSION: EA can reduce the level of inflammation and improve insulin sensitivity in OIR rats.