ABSTRACT
The fruit of Pandanus tectorius (PTF) has a long history of use as a folk medicine to treat hyperlipidemia in Hainan province, South China. Our previous studies have shown that the n-butanol extract of PTF is rich in caffeoylquinic acids and has an adequate therapeutic effect on dyslipidemic animals induced by high-fat diet. In this work, seven caffeoylquinic acids isolated from PTF were screened for the lipid-lowering activity in HepG2 hepatoma cells. Oil-Red O staining, microscopy and intracellular triglyceride (TG) and total cholesterol (TC) quantification showed that 3-O-caffeoylquinic acid (3-CQA), 3, 5-di-O-caffeoylquinic acid (3,5-CQA), and 3,4,5-tri-O-caffeoylquinic acid (3,4,5-CQA) significantly inhibited lipid accumulation induced by oleic acid and decreased intracellular levels of TC and TG in a dose-dependent manner. These three caffeoylquinic acids showed no significant cytotoxicity at concentrations of 1 -50 μmol x L(-1) as determined by MTT assay. Realtime quantitative PCR revealed that 3-CQA and 3, 5-CQA significantly increased the expression of lipid oxidation-related genes PPARα, CPT-1 and ACOX1 while 3-CQA, 3, 5-CQA and 3,4,5-CQA decreased the expression of lipogenic genes SREBP-1c, SREBP-2, HMGR, ACC, FAS. Overall, 3-CQA, 3, 5-CQA and 3, 4, 5-CQA may be the principal hypolipidemic components in PTF which can decrease intracellular lipid accumulation through up-regulating the expression of lipid oxidative genes and down-regulating the expression of lipogenic genes.
Subject(s)
Humans , Carcinoma, Hepatocellular , Metabolism , China , Cholesterol , Metabolism , Gene Expression Regulation , Hep G2 Cells , Lipid Metabolism , Liver Neoplasms , Metabolism , Oleic Acid , Pandanaceae , Chemistry , Quinic Acid , Chemistry , Sterol Regulatory Element Binding Protein 1 , Triglycerides , MetabolismABSTRACT
Objective: To study the organic acids in the leaves of Cerbera manghas. Methods: The constituents were isolated by repeated column chromatography and their structures were elucidated on basis of physico-chemical constants and spectral data analyses. Results: Seven compounds were obtained and determined to be m-carboxyphenylacetic acid (1), p-hydroxybenzoic acid (2), protocatechuic acid (3), p-hydroxycin-namic acid (4), isophthalic acid (5), vanillic acid (6), and succinic acid (7). Conclusion: Compound 1 is a new natural product, compounds 2-6 are obtained from the plants of Cerbera L. for the first time.
