[Effect of electroacupuncture stimulation of different acupoint groups on lipid metabolism and liver TLR4/NF-κB signaling in obese rats].

Abstract

To observe the effect of electroacupuncture (EA) of different acupoint combinations on lipid metabolism and liver Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling in obese rats, so as to explore the specificity of regulatory effects of different acupoints for obesity. Male SD rats were randomly divided into normal control, model, hindlimb acupoint EA ［"Fenglong" (ST40)-"Zusanli" (ST36), hindlimb EA］, abdominal acupoint EA ［("Zhongwan" (CV12)-"Tianshu" (ST25), "Guanyuan" (CV4) - the opposite ST25, abdominal EA］, BiaoBen-acupoint EA ［ST40-ST36, CV12 -CV4, ST25, BiaoBen EA］ groups, with 10 rats in each group. The obesity model was induced by feeding the rats with high fat diet. EA (2 Hz, 1 mA) was applied to the acupoint groups mentioned above for 10 min (per acupoint group), 3 times a week for 8 weeks. After the treatment, the body weight and food intake in each group were recorded. The contents of serum total cholesterol (TC), triglyceride (TG), non-esterified fatty acid (NEFA) were detected by using an automatic biochemical analyzer. The expression levels of TLR4 and NF-κB p65 mRNAs and proteins in the liver tissue were detected by quantitative real-time PCR and Western blot, separately. Compared with the normal group, the body weight and food intake, serum TC, TG and NEFA contents, hepatic TLR4 and NF-κB p65 protein and gene expression were significantly increased in the model group (P<0.05, P<0.01). After the treatment, compared with the model group, the body weight, food intake, TC, TG, NEFA, TLR4 and NF-κB p65 protein and mRNA expression were significantly decreased in the hindlimb EA, abdominal EA and BiaoBen EA groups (P<0.05, P<0.01). Comparison among the 3 treatment groups showed that the serum TC, TG and NEFA contents were significantly lower in the hindlimb EA and BiaoBen EA groups than in the abdominal EA group (P<0.01，P<0.05). The expression levels of TLR4 and NF-κB p65 mRNAs and proteins were significantly lower in the BiaoBen EA group than in the hindlimb EA and abdominal EA groups (P<0.01, P<0.05). BiaoBen EA is superior to abdominal EA in improving lipid metabolism in obesity rats, which may be related to its stronger effectiveness in down-regulating hepatic TLR4/NF-κB p65 signaling.