Regulatory Effect Of Pyranoanthocyanin Vitisin A On Disorders Of Triglyceride Metabolism

Objective:The pyranoanthocyanin Vitisin A is a class of anthocyanin derivatives which formed by the reaction of anthocyanins with pyruvate,an intermediate product of glucose metabolism.The pyranoanthocyanins are produced in red wines during the fermentation and aging processes.During fermentation,pyranoanthocyanins performed better stability.They are major contributors to the color of red wines.Most pyranoanthocyanins have higher biological activity than anthocyanins in vitro.The disorder of triglyceride level in liver is one of the important reasons for the occurrence of lipid metabolism diseases such as hypertriglyceridemia,diabetes,or nonalcoholic fatty liver disease.In the present study,we prepared Vitisin A firstly,and then investigated the triglyceride-lowing effect of Vitisin A in HepG2 cells which were induced with oleic and palmitic acids.At last,apolipoprotein E-deficient(ApoE^-/-)mice fed a high-fat diet were used to investigate the triglyceride-lowing effect of Vitisin A in the liver.The specific research contents are as follows:（1）We used pyruvate and cyanidin-3-O-glucoside（C3G）combine to Vitisin A,and then it was separated by the macroporous resin and medium pressure liquid chromatography.（2）Cell experiment:The lipid-lowing effect of concentrations（0-200μM）of C3G and Vitisin A were evaluated in 600μM free fatty acid（oleic acid:palmitic acids=2:1）induced HepG2 cells after treated for 24 h.Cells divided into Blank group,Model group,Vitisin A group,C3G group,AICAR group.（3）Animal experiment:To test the ability to regulate lipid accumulation of Vitisin A,mice at age of 6 weeks were used to be treated with a high-fat diet and intragastric administration of 100mg/kg·bw Vitisin A and C3G.Mice divided into 4 groups:blank control group（Blank group）,high-fat diet group（HFD group）,high-fat diet+100 mg/kg·bw Vitisin A group（Vitisin A group）,high-fat diet+100 mg/kg·bw C3G group（C3G group）.1)Mice were fed for 12 weeks to investigated plasm and liver biochemical indexes.2)The oil O red staining,hematoxylin-eosin staining,and nonalcoholic fatty liver disease activity score were used for the histological evaluation of mice liver to investigate the liver-protective action of Vitisin A.3)The impact of Vitisin A in high-fat diet-fed mice liver was considered by analyzing the proteins and genes which are related to triglyceride metabolism with Western Blot and Real-time quantitative PCR.We found that:（1）Cell experiment:Vitisin A could lower triglyceride level in free fatty acid induced HepG2 cells compared with Model group,and it showed a better triglyceride-lowing effect than C3G at same concentration（50μM,100μM,200μM）.（2）Animal experiment:1)Compared with HFD group,the intragastric administration of Vitisin A could reduce plasm and liver triglyceride level in mice,and Vitisin A had a better triglyceride-lowing ability than C3G.2)Intake of Vitisin A could inhibit the synthesis of fatty acid through suppress the transform of acetyl coenzyme A to malonyl-coenzyme A during lowering the activity of ACC and inhibit the expression of FASN.3)Vitisin A could adjust the expression of CPT1A through AMPK/SIRT1/PGC-1αpathway and PPAR-α/PGC-1αpathway to increase long-chain fatty acid used and mitochondrial fatty acidβ-oxidation.Intake of Vitisin A could up-regulate the expression of ACOX-1 through up-regulating the expression of PPAR-αto increase very long chain fatty acidsβ-oxidation in peroxisome.In conclusion,Vitisin A showed a better triglyceride-lowing effect than C3G at same concentration in both HepG2 cells and mice.Vitisin A could regulate triglyceride level in mice through inhibiting the synthesis of fatty acid and up-regulating fatty acidβ-oxidation in the liver.This study provides a important science basis for Vitisin A as a natural functional factor to prevent hypertriglyceridemia in high-fat diet.