大黄鱼硫酸软骨素的制备及降血脂活性研究OA

This study utilized large yellow croaker bones as raw materials to prepare chondroitin sulfate through processes including dilute alkali enzymatic hydrolysis,ethanol precipitation,and dialysis for impurity removal.The structural characteristics of large yellow croaker chondroitin sulfate(LCS)were further investigated.Subsequently,a hyperlipidemic zebrafish model was established to explore its hypolipidemic activity.Through the determination of physical and chemical properties,ultraviolet spectrophotometer,Fourier transform in-frared spectrometer,high performance gel permeation chromatography,and 1 H nuclear magnetic resonance spectroscopy,it was found that the extraction rate and content of CS in large yellow croaker bone reached 0.46％and 92.59％,respectively,and the content of glucuron-ic acid and protein in LCS was 35.64％and 1.27％,respectively.The functional group composition was similar to that of CS standard.The weight-average molecular weight of LCS was 33 874 Da,and the degree of sulfation occurred at the point of C-6 and C-4 was similar.The results of oil red O staining showed that the high-fat diet successfully induced hyperlipidemia in zebrafish.After intervention with dif-ferent mass concentrations of LCS(40,80,and 200 μg/mL),the lipid level significantly decreased(P＜0.05).Hematoxylin-eosin stai-ning indicated that with the increase in LCS mass concentration,the arrangement of hepatocytes in livers gradually changed from loose to tight,and the fat vacuoles gradually decreased.LCS could significantly reduce the levels of low-density lipoprotein cholesterol,total cho-lesterol,and triglycerides in hyperlipidemic zebrafish(P＜0.05),and increase the level of high-density lipoprotein cholesterol(P＜0.05).The expression levels of genes related to lipid metabolism in zebrafish were determined using quantitative real-time polymerase chain reaction.It was found that LCS could alleviate lipid metabolism disorder in the hyperlipidemic zebrafish model by down-regulating the expression of lipid synthesis-related genes(Srebf1,Acaca,Fasn,Hmgcrb)and up-regulating the expression of lipid decomposition genes(Pparg,Rora,Ldlr,Cyp7a1a).