Effect of butylated hydroxytoluene, curcumin, propyl gallate and thiabendazole on cytochrome P450 forms in cultured human hepatocytes

1. The objective of this study was to investigate the effects of four food chemicals, namely butylated hydroxytoluene (BHT), curcumin (CC), propyl gallate (PG) and thiabendazole (TB), on cytochrome P450 (CYP) forms in cultured human hepatocytes. 2. Treatment of human hepatocytes for 72 h with 2-200 μM TB produced concentration-dependent...

Transcriptome analysis provides new insights into liver changes induced in the rat upon dietary administration of the food additives butylated hydroxytoluene, curcumin, propyl gallate and thiabendazole

Transcriptomics was performed to gain insight into mechanisms of food additives butylated hydroxytoluene (BHT), curcumin (CC), propyl gallate (PG), and thiabendazole (TB), additives for which interactions in the liver can not be excluded. Additives were administered in diets for 28 days to Sprague-Dawley rats and cDNA microarray experiments were...

Human glutathione S-transferase-mediated glutathione conjugation of curcumin and efflux of these conjugates in caco-2 cells

Curcumin, an α,β-unsaturated carbonyl compound, reacts with glutathione, leading to the formation of two monoglutathionyl curcumin conjugates. In the present study, the structures of both glutathione conjugates of curcumin were identified by LC-MS and one- and two-dimensional 1H NMR analysis, and their formation in incubations with human...

Inhibition of multidrug resistance proteins MRP1 and MRP2 by a series of α,β-unsaturated carbonyl compounds

To study the possible interplay between glutathione metabolism of and MRP inhibition by thiol reactive compounds, the interactions of a series of α,β-unsaturated carbonyl compounds with multidrug resistance proteins 1 and 2 (MRP1/ABCC1 and MRP2/ABCC2) were studied. α,β-Unsaturated carbonyl compounds react with glutathione, and therefore either...

Toxicogenomics concepts and applications to study hepatic effects of food additives and chemicals

Transcriptomics, proteomics and metabolomics are genomics technologies with great potential in toxicological sciences. Toxicogenomics involves the integration of conventional toxicological examinations with gene, protein or metabolite expression profiles. An overview together with selected examples of the possibilities of genomics in toxicology...

Time- and dose-dependent effects of curcumin on gene expression in human colon cancer cells

Background. Curcumin is a spice and a coloring food compound with a promising role in colon cancer prevention. Curcumin protects against development of colon tumors in rats treated with a colon carcinogen, in colon cancer cells curcumin can inhibit cell proliferation and induce apoptosis, it is an anti-oxidant and it can act as an anti...

Do aberrant crypt foci have predictive value for the occurrence of colorectal tumours? Potential of gene expression profiling in tumours

The effects of different dietary compounds on the formation of aberrant crypt foci (ACF) and colorectal tumours and on the expression of a selection of genes were studied in rats. Azoxymethane-treated male F344 rats were fed either a control diet or a diet containing 10% wheat bran (WB), 0.2% curcumin (CUR), 4% rutin (RUT) or 0.04% benzyl...

Interplay between MRP Inhibition and Metabolism of MRP Inhibitors: The Case of Curcumin

The multidrug resistance proteins MRP1 and MRP2 are efflux transporters with broad substrate specificity, including glutathione, glucuronide, and sulfate conjugates. In the present study, the interaction of the dietary polyphenol curcumin with MRP1 and MRP2 and the interplay between curcumin-dependent MRP inhibition and its glutathione-dependent...

An analysis of the possibility for health implications of joint actions and interactions between food additives

The possibility that structurally unrelated food additives could show either joint actions or interactions has been assessed based on their potential to share common sites and mechanisms of action or common pathways of elimination. All food additives approved in the European Union and allocated numerical acceptable daily intake values were...

The application of in vitro data in the derivation of the acceptable daily intake of food additives

The acceptable daily intake (ADI) for food additives is commonly derived from the NOAEL (no-observed-adverse-effect level) in long-term animal in vivo studies. To derive an ADI a safety or uncertainty factor (commonly 100) is applied to the NOAEL in the most sensitive test species. The 100-fold safety factor is considered to be the product of...

Electron ionization mass spectrometry of curcumin analogues: An olefin metathesis reaction in the fragmentation of radical cations

The natural compound curcumin, used in cosmetics, traditional medicines and as a spice in food, is known as a multi-factorial anti-inflammatory agent. To study the anti-inflammatory activity of curcumin derivatives, 24 analogues were synthesized and their structures were confirmed by 1H NMR and electron ionization (EI) mass spectrometry. Most...

Inhibition of glutathione S-transferase activity in human melanoma cells by alfa, beta-unsaturated carbonyl derivatives: Effects of acrolein, cinnamaldehyde, citral, crotonaldehyde, curcumin, ethacrynic acid, and trans-2-hexenal

The glutathione S-transferase (GST) activity towards 1-chloro-2,4-dinitrobenzene in intact human IGR-39 melanoma cells was determined by the quantification by HPLC-analysis of the excreted glutathione (GSH) conjugate (S-(2,4-dinitrophenyl)glutathione; DNPSG). The major GST subunit expressed in these melanoma cells is the π-class GST subunit P1....