Bitter gourd (Momordica charantia) extract activates peroxisome proliferator-activated receptors and upregulates the expression of the acyl CoA oxidase gene in H4IIEC3 hepatoma cells
Bitter gourd (Momordica charantia) extract activates peroxisome proliferator-activated receptors and upregulates the expression of the acyl CoA oxidase gene in H4IIEC3 hepatoma cells
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DOI：
10.1159/000073966
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发表时间：
2003-01-01
影响因子：
11
通讯作者：
Huang, CJ
中科院分区：
文献类型：
--
作者：
Chao, CY;Huang, CJ
过氧化物酶体增殖物激活受体α(PPARpha)是一种配体依赖的转录因子，调节与脂质代谢和转运有关的基因的表达。PPARα的配体/激活剂，如贝特类药物，可能具有降血脂作用。为了鉴定含有PPARpha激活剂的食品，利用稳定转染(UAS)(4)-tk-碱性磷酸酶报告基因和Gal4-rPARpha LBD嵌合受体的CHO-K1细胞克隆进行反式激活实验，筛选各种食品原料的乙酸乙酯(EA)提取物。结果表明，苦瓜(Momordica Charantia)的EA提取物对PPARα的激活作用相当于甚至高于PPARα的已知配体Wy-14643。该提取物还能显著激活PPAR-γ，相当于0.5微米的BRL-49653。对PPARα的活性主要存在于有机溶剂的可溶部分。从整个果实中提取的EA提取物的活性显著高于从种子或果肉中提取的提取物。将苦瓜EA提取物加入到过氧化物酶增殖剂反应性小鼠肝癌细胞系H4IIEC3中处理72h后，细胞的酰化CoA氧化酶活性显著提高，该酶和脂肪酸结合蛋白的mRNA表达也显著增加，表明苦瓜EA提取物能够作用于该细胞系中一条天然的PPARpha信号通路。因此，有必要进一步研究苦瓜与PPAR相关的健康益处。版权所有(C)2003国家科学委员会，中华民国和S.Karger AG，巴塞尔。
Peroxisome proliferator-activated receptor alpha (PPARalpha) is a ligand-dependent transcription factor that regulates the expression of genes involved in lipid metabolism and transport. Ligands/activators of PPARalpha, like fibrate-type drugs, may have hypolipidemic effects. To identify food that contains activators of PPARalpha, a transactivation assay employing a clone of CHO-K1 cells stably transfected with a (UAS)(4)-tk-alkaline phosphatase reporter and a chimeric receptor of Gal4-rPPARalpha LBD was used to screen ethyl acetate ( EA) extracts of a large variety of food materials. It was found that the EA extract of bitter gourd ( Momordica charantia), a common oriental vegetable, activated PPARalpha to an extent that was equivalent to or even higher than 10 muM Wy-14643, a known ligand of PPARalpha. This extract also activated PPARgamma to a significant extent which was comparable to 0.5 muM BRL-49653. The activity toward PPARalpha was mainly in the soluble fraction of the organic solvent. The EA extract prepared from the whole fruit showed significantly higher activity than that from seeds or flesh alone. The bitter gourd EA extract was then incorporated into the medium for treatment of a peroxisome proliferator-responsive murine hepatoma cell line, H4IIEC3, for 72 h. Treated cells showed significantly higher activity of acyl CoA oxidase and higher expressions of mRNA of this enzyme and fatty acid-binding protein, indicating that the bitter gourd EA extract was able to act on a natural PPARalpha signaling pathway in this cell line. It is thus worth further investigating the PPAR-associated health benefits of bitter gourd. Copyright (C) 2003 National Science Council, ROC and S. Karger AG, Basel.