Oral Concentrated Grape Juice Suppresses Expression of NF-kappa B, TNF-α and iNOS in Experimentally Induced Colorectal Carcinogenesis in Wistar Rats

The aim of this study was to evaluate the effects of grape juice on colon carcinogenesis induced by azoxymethane(AOM) and expression of NF-kB, iNOS and TNF- α.
Methods: Forty male Wistar rats were divided into 7 groups:G1, control; G2, 15 mg/kg AOM; G3, 1% grape juice 2 weeks before AOM; G4, 2% grape juice 2 weeks beforeAOM; G5, 1% grape juice 4 weeks after AOM; G6, 2% grape juice 4 weeks after AOM; G7, 2% grape juicewithout AOM. Histological changes and aberrant crypt foci (ACF) were studied, while RNA expression of NFkB,TNF- and iNOS was evaluated by qPCR.
Results: The number of ACF was higher in G2, and G4 presenteda smaller number of crypts per focus than G5 (p=0.009) and G6. Small ACF (1-3) were more frequent in G4compared to G2, G5 and G6 (p=0.009, p=0.009 and p=0.041, respectively). RNA expression of NF-kB was lowerin G3 and G4 compared to G2 (p=0.004 and p=0.002, respectively). A positive correlation was observed betweenTNF- α and NF-kB gene expression (p=0.002). In conclusion, the administration of 2% grape juice before AOMreduced the crypt multiplicity, attenuating carcinogenesis. Lower expression of NF-kB was observed in animalsexposed to grape juice for a longer period of time, regardless of concentration.