Suppression of inflammation in ulcerative colitis rats by avocado and pomegranate

Abstract

BackgroundPomegranate seed oil (PSO) and avocado seed oil (ASO) are natural polyphenols with established anti-inflammatory activity. PurposeThis study aimed to investigate the molecular mechanisms underlying the therapeutic efficacy of PSO and ASO in experimental ulcerative colitis (UC) with reference to sulfasalazine (SLZ). MethodsEighty male albino rats were divided equally into 8 groups; Normal, PSO, ASO, SLZ, UC-control, (UC+PSO), (UC+ASO) and (UC+SLZ) groups. Colitis was induced by intra-rectal injection of acetic acid. PSO (0.5ml/ 200g), ASO (1ml/ 250g) and SLZ (100mg/kg) were administered orally once/day for 14 days, 24h after colitis induction. Colitis was evaluated by measuring disease activity index (DAI), colon weight/length ratio and histologic inflammatory score. Vascular endothelial growth factor receptor-2 (VEGFR-2), colonic macrophage migration inhibitory factor (MIF), and malondialdehyde (MDA) were determined. Colonic gene expression of TNF-α, VEGF and heme oxygenase-1 (HO-1) were also estimated. ResultsPSO and ASO treatments to UC rats significantly reduced DAI, weight/length ratio, VEGFR-2, and colon histologic inflammatory score versus UC-controls. ASO significantly suppressed MIF levels and TNF-α expression greater than PSO. However, PSO was more significant than ASO in reducing MDA levels and up-regulating HO-1 expression. Both oils significantly down-regulated VEGF expression. The obtained biochemical and histological changes induced by UC were nearly corrected by SLZ. ConclusionThe proved beneficial effect of PSO and ASO as anti-inflammatory, anti-angiogenic, and antioxidant in UC rats could be mediated by suppression of TNF-α, VEGF, and MIF and up-regulation of HO-1.