cyanidin-3-o-beta-glucopyranoside and 3-nitrotyrosine

Cyanidin-3-glucoside (C3G) is a major anthocyanin in berries and a potential nutritional supplement for preventing retinal degeneration. However, the protective mechanism of C3G and its metabolites, protocatechuic acid (PCA) and ferulic acid (FA), remain unclear. The molecular mechanisms of C3G and its metabolites against retinal photooxidative damage in vivo are investigated.. Pigmented rabbits were orally administered C3G, PCA, and FA (0.11 mmol/kg/day) for 3 weeks. Electroretinography, histological analysis, and TUNEL assay showed that C3G and its metabolites attenuated retinal cell apoptosis. The expression of oxidative stress markers were upregulated after light exposure but attenuated by C3G and FA, which may be attributed to the elevated secretion and expression of heme oxygenase (HO-1) and nuclear factor erythroid-2 related factor 2 (Nrf2). C3G, PCA, and FA attenuated the secretion or expression of inflammation-related genes; FA suppressed nuclear factor kappa B (NF-κB) activation. The treatments attenuated the light-induced changes on certain apoptotic proteins and angiogenesis-related cytokines.. C3G and FA reduced light-induced retinal oxidative stress by activating the Nrf2/HO-1 antioxidant pathway. FA attenuated the light-induced retinal inflammation by suppressing NF-κB activation. C3G and its metabolites attenuated the photooxidation-induced apoptosis and angiogenesis in the retina.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Anthocyanins; Antioxidants; Apoptosis; Coumaric Acids; Cytokines; Deoxyguanosine; Glucosides; Heme Oxygenase-1; Hydroxybenzoates; In Situ Nick-End Labeling; Light; NF-E2-Related Factor 2; NF-kappa B; Oxidative Stress; Rabbits; Retina; Retinal Degeneration; Signal Transduction; Tyrosine; Up-Regulation

Anthocyanins are a group of naturally occuring phenolic compounds related to the coloring of plants, flowers and fruits. These pigments are important as quality indicators, as chemotaxonomic markers and for their antioxidant activities. Here, we have investigated the therapeutic efficacy of anthocyanins contained in blackberry extract (cyanidin-3-O-glucoside represents about 80% of the total anthocyanin contents) in an experimental model of lung inflammation induced by carrageenan in rats. Injection of carrageenan into the pleural cavity elicited an acute inflammatory response characterized by fluid accumulation which contained a large number of neutrophils as well as an infiltration of polymorphonuclear leukocytes in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate (NOx) and prostaglandin E2 (PGE2). All parameters of inflammation were attenuated in a dose-dependent manner by anthocyanins (10, 30 mg kg(-1) 30 min before carrageenan). Furthermore, carrageenan induced an upregulation of the adhesion molecule ICAM-1, nitrotyrosine and poly (ADP-ribose) synthetase (PARS) as determined by immunohistochemical analysis of lung tissues. The degree of staining was lowered by anthocyanins treatment. Thus, the anthocyanins contained in the blackberry extract exert multiple protective effects in carrageenan-induced pleurisy.

Topics: Acute Disease; Animals; Anthocyanins; Carrageenan; Dinoprostone; Exudates and Transudates; Fruit; Glucosides; Immunohistochemistry; Inflammation; Intercellular Adhesion Molecule-1; Lipid Peroxidation; Lung; Male; Malondialdehyde; Neutrophils; Nitrates; Nitrites; Peroxidase; Plant Extracts; Pleurisy; Poly(ADP-ribose) Polymerases; Rats; Rats, Sprague-Dawley; Time Factors; Tyrosine