[Electroacupuncture improves obesity and promotes white adipose tissue browning by regulating central glucagon-like peptide-1].

OBJECTIVE: To observe the effect of electroacupuncture （EA） on white adipose tissue （WAT） browning by regulating central glucagon-like peptide-1 （GLP-1）, so as to explore the possible central mechanisms of EA in improving obesity. METHODS: Thirty male Wistar rats were randomly divided into normal group, model group, EA group, HM3D group, and EA+HM4D group, with 6 rats in each group. The obesity rat model was obtained by feeding with high-fat diet for 8 weeks. Adeno-associated virus combined with DREADDs was injected into bilateral nucleus of solitary tract （NTS）, with rAAV-GLP-1+rAAV-4D applied to the EA+HM4D group, rAAV-GLP-1+rAAV-3D applied to the HM3D group, and rAAV-GLP-1+rAAV-GFP applied to other 3 groups. After modeling, rats in the EA and EA+HM4D groups received EA treatment at bilateral "Zusanli"（ST36）, "Fenglong"（ST40）, "Guanyuan"（CV4） and "Zhongwan"（CV12）, with successive waves （2 Hz, 1 mA） for 10 minutes, 3 times a week, for a total of 8 weeks. Body mass of rats in each group were measured before and 2, 4, 6, and 8 weeks after intervention. Abdominal and perirenal WAT mass was weighed, serum triglyceride （TG） and total cholesterol （TC） contents were detected by using automatic analyzer, and nonestesterified fatty acid （NEFA） content was detected by using colorimetric assay kit. The morphology of abdominal WAT lipid droplets was observed by HE staining. The mRNA expressions of GLP-1 in NTS, AMPK in ventromedial nucleus of hypothalamus（VMH）, UCP1 and PGC-1α in subcutaneous fat were detected by real-time PCR. The protein expression levels of GLP-1, AMPK, phosphorylated-AMPK, UCP1 and PGC-1α were detected by Western blot. The activation level of GLP-1 neurons in NTS was observed by immunofluorescence. RESULTS: Compared with the normal group, abdominal WAT lipid droplets were enlarged, body weight, serum TG, TC, NEFA contents, abdominal and perirenal WAT mass, mRNA and protein expression levels of AMPK were significantly increased（P<0.01, P<0.05）, while GLP-1 neurons activation level, mRNA and protein expression levels of GLP-1, UCP1 and PGC-1α, and AMPK protein phosphorylation were decreased （P<0.01） in the model group. After EA intervention, body weight at 6 and 8 weeks after intervention and other indexes mentioned above were all significantly reversed （P<0.01, P<0.05） in the EA group in comparison with those of the model group. Compared with the EA group, the HM3D group had reduced abdominal WAT lipid droplets size, decreased serum TG, TC, and NEFA contents, and protein expression level of AMPK（P<0.01, P<0.05）, with increased mRNA and protein expression levels of GLP-1, UCP1 and PGC-1α, and phosphorylation level of AMPK protein（P<0.01, P<0.05）, while the EA+HM4D group had enlarged abdominal WAT lipid droplets, increased body weight 6 and 8 weeks after intervention, abdominal and renal WAT mass, and NEFA content （P<0.01, P<0.05）, with decreased serum TG content, activation level of GLP-1 neurons in the NTS, mRNA and protein expression levels of GLP-1, UCP1 and PGC-1α （P<0.01, P<0.05）, as well as down-regulated phosphorylation of AMPK protein and mRNA （P<0.01, P<0.05）. CONCLUSION: EA can effectively promote the browning of WAT, which may be related to the activation of GLP-1 neurons in the NTS, as well as the promotion of the phosphorylation of AMPK in the VMH and up-regulation of UCP1.

[Mechanisms of electroacupuncture underlying treatment of osteoporosis based on HDAC2-mediated osteoblast differentiation pathway].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on expression of histone deacetylase 2 (HDAC2), histone H3, bone formation related genes and proteins in osteoporosis rats, so as to reveal its mechanisms underlying improvement of osteoporosis. METHODS: Female SD rats were randomly divided into 4 groups: sham operation, model, EA and medication (n＝ 10 rats in each group). The osteoporosis model was established by castration. EA (2 Hz, 1 mA) was applied to bilateral "Shenshu" (BL23) and "Pishu" (BL20) for 10 min, once every other day for 8 weeks. Rats of the medication group received subcutaneous injection of 17 ß-estradiol (100 µg/kg, 20 µg/mL). The bone quality and quantity including the cortical bone mineral density (CBMD), trabecular bone mineral density (TBMD), ratio of bone volume /total volume (BV /TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb. Sp), trabecular bone pattern factor (Tb.Pf), and structure model index (SMI) of the right thigh-bone were detected by using a micro-computed tomography. Serum alkaline phosphatase (ALP) and estrogen 2 (E2) contents were assayed by using colorimetry and ELISA, expression levels of HDAC2, histone H3 and Runx2 in the thigh-bone were detected using Western blot, and that of Runx2 mRNA was detected using quantitative real-time PCR, separately. The co-expression of Ac-histone H3/Runx2 and Runx2/ALP was observed by using immunofluorescence histochemical staining. RESULTS: After modeling, the levels of TBMD, BV/TV, Tb.Th, and Tb.N, serum E2 and ALP, and expression of Runx2 protein and mRNA, Ac-histone and ALP proteins were significantly lower (P<0.01), and those of Tb.Sp, Tb.Pf and SMI, HDAC2 and histone H3 proteins were significantly higher (P<0.01) in the model group than those in the sham operation group. After the interventions, the decrease of TBMD, BV/TV, Tb.N，Runx2 protein and mRNA，ALP in both EA and medication groups, serum E2 in the medication group, and Ac-histone H3 in the EA group, and the increase of Tb.Sp in the medication group, Tb.Pf, SMI, and HDAC2 in both EA and medication groups, and histone H3 in the EA group were reversed (P<0.01, P<0.05). No significant changes were found in the levels of CBMD after modeling relevant to the sham operation group, and after EA and medication interventions (P>0.05). The effects of EA were significantly superior to 17 ß-estradiol in down-regulating the expression of HDAC2 and histone H3 proteins and in up-regulating expression of Ac-histone H3 protein (P<0.01，P<0.05)．. CONCLUSION: EA treatment can increase bone density, increase bone mass and trabecular bone, and promote trabecular bone rod-like changes in plate shape in osteoporosis rats, which is related to its effect in up-regulating the expression of Ac-histone H3 protein, and down-regulating the expression of bone formation-related proteins.