Naringenin inhibits lipid accumulation by activating the AMPK pathway in vivo and in vitro

The aim of this study was to explore the lipid-lowering effect of naringenin and the underlying mechanism in high-fat-diet-fed SD rats and 3T3-L1 cells.In this study,SD rats were divided into the normal chow diet group(NCD),high fat diet group(HFD),three treatment groups feeding high-fat diet with naringenin(100,200,400 mg/kg)for 12 weeks.Results indicated that naringenin treatment decreased total cholesterol(TC),triglyceride(TG)and the non-high-density lipoprotein cholesterol(non-HDL-C)levels in serum.Naringenin also alleviated hepatic steatosis and reduced the adipocyte size in the epididymis in high-fat-diet-induced SD rats.In addition,naringenin(25−75μg/mL)decrease TG and TC levels in 3T3 mature adipocytes.The molecular mechanism of naringenin in the treatment of obesity were predicted by using network pharmacology.Real-time PCR analysis results showed that naringenin regulated the expression of lipid metabolism genes.Meanwhile,naringenin increased the AMPK(AMP-activated protein kinase)activity and the expression of AMPK phosphorylated protein in 3T3 mature adipocytes.And the inhibitory effect of naringenin on lipid accumulation in 3T3 adipocytes was abolished by Compound C.Molecular docking results indicated that naringenin could bind to AMPK protein.These results indicated naringenin reduced lipid accumulation through AMPK pathway.

Microstructure Evolutions and Properties of Al-Cu Alloy Joint in the Pulsed Power Ultrasonic-Assisted GMAW

The pulsed power ultrasonic-assisted gas metal arc welding(PU-GMAW)is a new development hybrid welding method.The influences of the pulsed power ultrasonic on the microstructure evolution of the welded joint of Al-Cu alloy were investigated by using scanning electron microscopy,transmission electron microscope and electron back scattering diffraction.The results showed that the efficient heat input in the PU-GMAW was increased by above 100%compared with the traditional GMAW.The grain and eutectic of the PU-GMAW weld seam were refined compared with that of the GMAW.Cavitation and acoustic streaming induced the dendrite fragmentation(α-Al)and heterogeneous nucleation,which were the main reasons for the grain refinement.The microhardness of the PU-GMAW welded joint was improved compared with that of the GMAW owing to the change of the eutectic and grain.