Evaluation of the effect of Punica granatum juice and punicalagin on NFκB modulation in inflammatory bowel disease.

Punica granatum L. (Lythraceae) inhibits cancer cell proliferation and apoptosis through the modulation of cellular transcription factors and signaling proteins. No pharmacological work is reported on the effects of P. granatum juice on the cellular signaling pathways involved in initiation and progression of inflammation. The present investigation evaluates the effect of P. granatum juice (PJ) and purified punicalagin (PW) on nuclear factor kappa B (NFκB) and the signaling pathways leading to its expression in colon inflammation. Male Sprague-Dawley rats were divided into six groups: positive and negative control, vehicle (50 % ethanol), standard (5-ASA 100 mg/kg, p.o.), PJ (400 mg/kg, p.o.), PW (4 mg/kg, p.o.). Colitis was induced with 2,4-dinitrobenzene sulfonic acid and animals were euthanized on 18th day. Colon samples collected were subjected to various histological assessment (CMDI, DAI), and biochemical parameters (MPO, MDA, SOD, NO). Gene expression study was carried out using RT-PCR for cytokines (TNF-α, IL-1β, IL-18 and NF-κβ). Pretreatment with PJ and PW significantly (p < 0.05) lowered the disease extent and severity as indicated by reduction in CMDI (2 ± 0.31) and DAI (1.83(#) ± 0.22) when compared with DNBS-treated rats (3.83* ± 0.17). Gene expression studies showed decreased mRNA levels of TNF-α, IL-18, and IL-1β in PJ and PW-treated groups. NF-κβ mRNA levels were found to be reduced 84 and 64 % by PJ and PW, respectively. These results suggest that P. granatum juice is more biologically active over punicalagin alone and can be potentially used for the treatment of inflammatory bowel disease.