Resveratrol, a polyphenol found in grapes, suppresses oxidative damage and stimulates apoptosis during early colonic inflammation in rats Antonio Ramo ´n Martı ´n, Isabel Villegas, Carmen La Casa, Catalina Alarco ´n de la Lastra * Department of Pharmacology, Faculty of Pharmacy, University of Seville, Profesor Garcı ´a Gonza ´lez Street 2, 41012 Sevilla, Spain Received 4 September 2003; accepted 15 December 2003 Abstract Oxidative stress, neutrophil infiltration, proinflammatory cytokines and eicosanoid generation are clearly involved in the pathogenesis of intestinal bowel disease. Resveratrol, a polyphenolic compound found in grapes and wine, has been shown to have anti-inflammatory, antioxidant, antitumour and immunomodulatory activities, however, its effects on experimental colitis remain unknown. We have investigated the effects of resveratrol on the colon injury caused by intracolonic instillation of trinitrobenzenesulphonic acid (TNBS) in rats. We determined the production of prostaglandin (PG)E 2 and PGD 2 in colon mucosa and the expression of cyclo-oxygenases (COX)-1 and -2 immunohistochemically. The inflammatory response was assessed by histology and myeloperoxidase activity, as an index of neutrophil infiltration. Interleukin-1b production, histological and histochemical analysis of the lesions were also carried out. Finally, since resveratrol has been found to modulate apoptosis we intended to elucidate its effects on colonic mucosa under early acute inflammatory conditions. Resveratrol (5–10 mg/kg/day) significantly reduced the degree of colonic injury, the index of neutrophil infiltration and the levels of the cytokine. Resveratrol did not revert the increased PGE 2 levels but produced a significant fall in the PGD 2 concentration. Compared with inflamed colon, no changes in staining for COX-1 were observed in colon of resveratrol and TNBS-treated rats. In contrast, COX-2 expression was decreased. Furthermore, resveratrol enhanced apoptosis compared with already high level induced by TNBS. In conclusion, resveratrol reduces the damage in experimentally induced colitis, alleviates the oxidative events and stimulates apoptosis. # 2004 Elsevier Inc. All rights reserved. Keywords: Resveratrol; TNBS (trinitrobenzenesulphonic acid); Neutrophils; Interleukin (IL)-1b; Prostaglandin (PG); Apoptosis 1. Introduction Resveratrol (3,5,4 0 -trihydroxy-trans-stilbene) is a natu- rally occurring stilbene found in grape skins and the red wines. The compound exerts striking inhibitory effects on diverse cellular events associated with tumour initiation, promotion, and progression [1]. Resveratrol is also reported to be a neuroprotective [2] and cardioprotective agent [3]. The compound has been shown to exert a strong inhibitory effect on lipid peroxides production and also to modulate lipoprotein metabolism [4]. Several studies within the last few years have shown that resveratrol exhibits potent antioxidative and anti-inflammatory effects [5,6]. How exactly resveratrol exerts its anti-inflammatory effects is not understood but they have been ascribed to its ability to disrupt arachidonic acid metabolism by inhibiting COX-1 and hydroxyperoxidase of COX-1 with an ED 50 of 3.7 mm [1]. This compound was also able to reduce COX-2 levels induced by lipopolysaccharide and phorbol 12-myr- istate and impaired the overexpression of COX-2 [7–9]. Besides inhibiting COX-2, resveratrol has been shown to suppress iNOS expression and subsequent NO production in culture cells [7,10,11]. Ulcerative colitis (UC) is a nonspecific inflammatory disorder involving primarily the mucosa and submucosa of the colon. Activated immune cells, primarily represented by neutrophils, macrophages, and cytotoxic T cells play the role of aggressors that attack and destroy the intestinal barrier either directly through physical contact or indirectly through the release of reactive oxygen and nitrogen meta- bolites, cytotoxic proteins, lytic enzymes, or cytokines Biochemical Pharmacology 67 (2004) 1399–1410 0006-2952/$ – see front matter # 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.bcp.2003.12.024 * Corresponding author. Tel.: þ34-95-455-1666; fax: þ34-95-423-3765. E-mail address: calarcon@us.es (C.A. de la Lastra). Abbreviations: TNBS, trinitrobenzenesulphonic acid; PG, prostaglan- din; COX, cyclo-oxygenase; MPO, myeloperoxidase; IL, interleukin; UC, ulcerative colitis.