Inhibitory effect of curcumin and its natural analogues on genotoxicity of heterocyclic amines from cooked food

1365-1372<span style="font-size: 16.5pt;mso-bidi-font-size:8.5pt;font-family:" times="" new="" roman","serif";="" color:black"="">Curcumin (C) and its natural analogues demethoxycurcumin (dmC) and bisdemethoxycurcumin (bdmC), known for their potent anti-inflammatory, antioxidant, antimutagenic and anticarcinogenic effects, were tested for their possible inhibitory effects against seven cooked food mutagens (heterocyclic amines): 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethyli midazo[ 4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[ 4,5-f]quinoxaline (MeIQx), 3-amino- 1 ,4-dimethyl-5H-pyrido[4,3-b ]indole (Trp-P-l), 3-amino-l-methyl-5H-pyrido[ 4,3-b]indole (Trp-P-2), 2-amino-l-methyl-6- <span style="font-size: 16.5pt;mso-bidi-font-size:8.5pt;font-family:" times="" new="" roman","serif";="" color:black"="">phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-6-methyldipyrido[1,2-a:3' ,2' -d]imidazole (Glu-P-1), in both TA98 and TA100 strains of Salmonella typhimurium using Ames &nbsp;Salmonella /reversion assay in the presence of Aroclor induced rat liver S9 homogenate. In the present investigations, curcumin as well as its two natural analogues i.e., dmC and bdmC were found to be highly effective in suppressing genotoxicity of all the tested cooked food mutagens in a dose-dependent manner, in both the frame shift (TA98) as well as base pair mutation sensitive (TA100 strains of S. typhimurium. However, bdmC appeared to be a relatively less active antimutagen compared <span style="font-size: 15.5pt;mso-bidi-font-size:7.5pt;font-family:" times="" new="" roman","serif";="" color:black"="">to <span style="font-size:16.5pt;mso-bidi-font-size:8.5pt; font-family:" times="" new="" roman","serif";color:black"="">C and dmC. More than 80% inhibition of mutagenicity was observed at 200 μg/plate in case of C and dmC in both T A98 and TA 100 against all tested cooked food mutagens. Whereas, bdmC showed 39-79% inhibition in TA100 and 60-80% inhibition in TA98, at a dose of 200 μg/plate. These findings warrant further biochemical, enzymatic and in vivo investigations in animal models as well as in humans to establish the chemoprotective effect of these agents against mutagenic heterocyclic amines found in cooked food. </span