Curcumin other effects

Some metabolites of curcumin (particularly tetrahydrocurcumin) may also participate in producing the observed effects of curcumin in different models because these metabolites display greater stabilities than the parent curcumin molecule at physiological pH. Recent data show similar modes of action of curcumin metabolites regarding antioxidant enzyme induction and inhibition of multidrug-resistant proteins. " Additional data indicate that curcumin may even act against other types of diseases such as atherosclerosis " " and Alzheimer s disease. " - " ... 

Curcumin is a hydrophobic polyphenol derived from turmeric the rhizome of the herb Curcuma longa. Traditionally, turmeric and other curcuminoids have been used in therapeutic preparations for various ailments in different parts of the world. Numerous therapeutic effects of curcumin/turmeric have been confirmed by modern scientific research. It is a highly pleiotropic molecule that modulates numerous targets, including the activation of transcription factors (e.g., NF-kB, STAT-3, AP-1, NRF-2, PPR-y, HIF-1), receptors (e.g., HER-2, IL-8, CXCR-4), kinases (e.g., EGFR, ERK, JAK, AAPK), cytokines (e.g., TNF, IL, MIP, MCP), enzymes (e.g., MMP, iNOS, GST, ATPase), and... 

Several in vivo chemoprevention studies have been reported with curcumin in gastric cancers. In some of the chemoprevention studies, curcumin fed as dietary turmeric (2% or 5%) to mice and Syrian golden hamsters significantly inhibited the benzo[a]pyrene-induced forestomach tumors. Furthermore, the incidence and multiplicity of forestomach tumors induced by benzo[a]pyrene in female Swiss mice were significantly inhibited by pure curcumin given 2 weeks before, during and after the carcinogen treatment. Other studies also revealed the chemopreventive effect of curcumin on benzo[a]pyrene-induced... 

To better understand the health effects of plant phenolic compounds and to better utilize them, it is necessary to know the molecular mechanisms by which plant phenolic compounds induce cytoprotective enzymes. In vitro studies indicated that plant phenolic compounds such as curcumin often inhibited the enzymatic activities of GST, UGT, SULT as well as cytochrome P450s [Oetari et al., 1996], suggesting that the induction of cytoprotective enzyme activities could not be explained by direct interaction with plant phenolic compounds. On the other hand, much evidence indicates that the increased activity of cytoprotective enzymes are mainly attributable to enhanced transcriptional activation and enzyme synthesis [Holtzclaw et al., 2004]. 

An area of considerable mleresi and the focus of many research projects is the antioxidant properties of spices. As was mentioned earlier, one of the earliest uses of spices was to help preserve foods. Little was understood at that time about the mode of action of the spices. It was simply known that they would help maintain the quality of the food to be stored. The area of antioxidant properties of spices is important for preserving the quality of foods but may also provide beneflcial health effects for people consuming the spices. This area will be covered in much more detail in an overview of the antioxidant properties of spices that is presented later in this book in the chapter by Madsen et a). One spice component in particular that lias received attention is curcumin. SeveraJ chapters address the eifectiveness of curcumin and possible ways to synthesize new curcuminoids. The investigators have looked at the various ways in which the compounds may be effective as an antioxidant in different sterns. This is an area that wifi continue to receive attention in the lesearch community as people continue to look for the specific health benefits that certain foods may offer. Spices will remain important for the flavor that they impart to foods and may also gain significance for other benefits they have to offer... 

Similarly, the phenolic antioxidants p-coumaric acid, ferulic acid, curcumin, and caffeic acid, which are found in coriander (as well as members of the Labiatae family, see below), inhibit the formation of 3-nitrotyrosine in vitro and may prevent lipid peroxidation in vivo [14, 15]. Caffeic acid and other hydroxycinnamic acids have also been found to exert an inhibitory effect on LDL oxidation, a known risk factor for CHD [16]. 

EGCG arrested UVB-induced steady-state message and transcriptional activation of the c-fos gene and accumulation of the c-fos protein in human keratinocyte ceU line, Ha-CaT via p38 MAPN (Chen et al. 1999). It also inhibited the stimulatory effect of PDGF-receptor p on the c-fos mRNA expression in cultured vascular smooth muscle cells Ifom rat aorta (Ahn et al. 1999). However, EGCG and other green tea polyphenols induced c-JUN/c-FOS in HT-29 and Caco-2 colon cancer ceU lines (Kim et al. 2004) and epidermal cells (Balasubramanian et al. 2002). Curcumin also inhibited the expression of c-FOS (Lin... 

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