Lin J K, Pan M H, Lin-Shiau S Y
Institutes of Biochemistry, College of Medicine, National Taiwan University, Taipei.
Biofactors. 2000;13(1-4):153-8. doi: 10.1002/biof.5520130125.
Curcumin is a major component of Curcuma species, which is commonly used as a yellow coloring and flavoring agent in foods. Curcumin has shown anti-carcinogenic activity in animals as indicated by its ability to block colon tumor initiation by azoxymethane and skin tumor promotion induced by phorbol ester TPA. Curcumin possesses anti-inflammatory activity and is a potent inhibitor of reactive oxygen-generating enzymes such as lipoxygenase/cyclooxygenase, xanthine dehydrogenase/oxidase and inducible nitric oxide synthase. Curcumin is also a potent inhibitor of protein kinase C, EGF-receptor tyrosine kinase and IkappaB kinase. Subsequently, curcumin inhibits the activation of NFkappaB and the expressions of c-jun, c-fos, c-myc and iNOS. It is proposed that curcumin may suppress tumor promotion through blocking signal transduction pathways in the target cells. Curcumin was first biotransformed to dihydrocurcumin and tetrahydrocurcumin and that these compounds subsequently were converted to monoglucuronide conjugates. These results suggest that curcumin-glucuronide, dihydro-curcumin-glucuronide, tetrahydrocurcumin-glucuronide and tetrahydrocurcumin are major metabolites of curcumin in mice.
姜黄素是姜黄属植物的主要成分，通常用作食品中的黄色色素和调味剂。姜黄素在动物实验中已显示出抗癌活性，这体现在它能够阻止由偶氮甲烷引发的结肠肿瘤以及佛波酯TPA诱导的皮肤肿瘤促进作用。姜黄素具有抗炎活性，是脂氧合酶/环氧化酶、黄嘌呤脱氢酶/氧化酶和诱导型一氧化氮合酶等产生活性氧的酶的有效抑制剂。姜黄素也是蛋白激酶C、表皮生长因子受体酪氨酸激酶和IkappaB激酶的有效抑制剂。随后，姜黄素抑制核因子κB的激活以及c-jun、c-fos、c-myc和诱导型一氧化氮合酶的表达。有人提出，姜黄素可能通过阻断靶细胞中的信号转导途径来抑制肿瘤促进作用。姜黄素首先被生物转化为二氢姜黄素和四氢姜黄素，随后这些化合物被转化为单葡萄糖醛酸共轭物。这些结果表明，姜黄素葡萄糖醛酸、二氢姜黄素葡萄糖醛酸、四氢姜黄素葡萄糖醛酸和四氢姜黄素是姜黄素在小鼠体内的主要代谢产物。
