Curcumin metabolism

Ireson, C. R. et al., Metabolism of the cancer chemopreventive agent curcumin in human and rat intestine, Cancer Epidemiol. Biomarkers Prev., 11, 105, 2002. 

Curcumin (diferuloylmethane) has very low oral bioavailability, but is rapidly absorbed and low nanomolar levels of the parent compound and its glucuronide and sulfate conjugates can be detected in human plasma and portal circulation after very high (nondietary) intakes (3.6g/day for 1 week). Metabolic reduction occurs in the liver, and glutathione adducts have been observed in vitro ... 

Piperine Piperine, molecular formula C17H19NO3, a component of black pepper (Piper nigrum), has been used in various traditional medicine preparations, and also as an insecticide. Piperine has various effects on human drug metabolizing enzymes, and is marketed under the brand name, Bioperine , as an adjunct for increasing bioavailability of various dietary supplements, especially curcumin, one of the active ingredients of turmeric (Curcuma longa). 

In a pilot trial with 12 patients with hepatic metastases from colorectal cancer, the concentrations of the curcumin in normal and malignant human liver tissue after patients received 450-3600 mg of curcumin daily for 1 week prior to surgery were not sufficient to elicit pharmacological activity, perhaps because of the extensive degree to which curcumin was metabolized in the intestine. 

Tamvakopoulos C, Dimas K, Sofianos ZD, Hatziantoniou S, Han Z, Liu ZL, Wyche JH, Pantazis P. 2007. Metabolism and anticancer activity of the curcumin analogue, dimethoxycurcumin. Clin Cancer Res 13 1269-1277. 

Iqbal M, Sharma SD, Okazaki Y, Fujisawa M, Okada S. 2003. Dietary supplementation of curcumin enhances antioxidant and phase II metabolizing enzymes in ddY male mice Possible role in protection against chemical carcinogenesis and toxicity. Pharmacol Toxicol 92 33-38. 

One example that can demonstrate the effectiveness and great promise of nanoencapsulation is the curcumin nanoemulsions. Curcumin is the major yellow pigment in turmeric Curcuma longa Linn). In South and Southeast Asia, curcumin preparation or turmeric has been used extensively to treat inflammatory conditions and chronic diseases (Reddy and Rao 2003). Orally administered curcumin usually has low systemic bioavailability. Only trace amounts of curcumin (or its metabolites) appear in the blood, and most of ingested curcumin is excreted in the feces. One reason is that curcumin has low solubility and does not disperse for absorption. The absorbed curcumin is rapidly metabolized in the intestine and liver to several reduction products (di-, tetra-, and hexa-hydrocurcumin and hexahydrocurcuminol) and... 

Rao, C.V., Simi, B., and Reddy, B.S., Inhibition by dietary curcumin of azoxymethane-induced ornithine decarboxylase, tyrosine protein kinase, arachidonic acid metabolism and aberrant crypt foci formation in the rat colon. Carcinogenesis (London), 14, 2219, 1993. 

Ravindranath, F. and Chandrasekhara, N., Metabolism of curcumin — studies with [3H]-curcumin, Toxicol., 22, 337, 1981. 

Conney, A.H., Lysz, T., Ferraro, T., Abidi, T.F., Manchand, P.S., Laskin, J.D., and Huang, M.T., Inhibitory effect of curcumin and some related dietary compounds on tumor promotion and arachidonic acid metabolism in mouse skin, Adv. Enzyme Regul, 31, 385-396, 1991. 

Srivastava, K.C., Bordia, A., and Verma, S.K., Curcumin, a major component of food spice turmeric (Curcuma longa), inhibits aggregation and alters eicosanoid metabolism in human blood platelets. Prostaglandins Leukot. Essent. Fatty Acids, 52 (4), 223-227, 1995. 

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