[Effect of Electroacupunctrue Stimulation at "Fenglong"(ST 40) on Expression of SREBP-1 c in Non-alcoholic Fatty Liver Disease Rats].

OBJECTIVE

To observe the effect of electroacupuncture(EA) stimulation at "Fenglong"(ST 40) on expression of sterol regulatory element binding protein-1 c(SREBP-1 c) in non-alcoholic fatty liver disease(NAFLD) rats, so as to reveal its mechanism underlying improving NAFLD.

METHODS

Male SD rats were randomly divided into normal diet group, high-fat diet group, ST 40 manual acupuncture (MA) group, ST 40 EA group and "Zusanli"(ST 36) EA group(=12 in each group). Apart from the normal diet group, rats in other groups were fed with high-fat diet to replicate NAFLD model. ST 40 MA group was treated with filiform needling for 20 min, EA (4 Hz/20 Hz, 5 mA) was applied to bilateral acupoints of ST 40 and ST 36 respectively for 20 min in the ST 40 EA group and ST 36 EA group, once a day for 4 weeks. The pathological changes of hepatic tissue were observed by HE staining. The contents of serum free fatty acid (FFA), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected by colorimetry. The expression of SREBP-1 c mRNA and protein in the hepatic tissue were detected by reverse transcription-polymerase chain reaction(RT-PCR) and Western blot, respectively.

RESULTS

HE staining showed that hepatocytes disorganized with diffuse bullous fat vacuolar changes in rats of the high-fat diet group, and small vesicle steatosis appeared in the ST 40 MA group. The liver cells arranged orderly and the steatosis decreased in the ST 40 EA group and ST 36 EA group. The contents of FFA, ALT, AST in serum and the expression levels of SREBP-1 c mRNA and protein in the hepatic tissue were significantly higher in the high-fat diet group than in the normal diet group(<0.01), while significantly lower in the MA and EA groups than in the high-fat diet group(<0.01). Furthermore, the effects of treatment in the ST 40 EA group were better than those in the ST 40 MA group(<0.01, <0.05). The FFA contents in serum and the expression levels of SREBP-1 c mRNA and protein were decreased in the ST 40 EA group in comparison with the ST 36 EA group(<0.05).

CONCLUSIONS

EA at ST 40 and ST 36 have a positive regulating effect on NAFLD rats, which may be related to down-regulating the expression of SREBP-1 c mRNA and protein in hepatic tissue, improving the endoplasmic reticulum stress and regulating lipid metabolic disorder, so as to relieve the inflammatory injury in hepatic tissue, and ST 40 works better.