title: Annatto extract and β-carotene enhances antioxidant status and regulate gene expression in neutrophils of diabetic rats.
abstract: Annatto (Bixa orellana L.) contains a mixture of orange-yellowish pigments due to the presence of various carotenoids that have antioxidant effect. The immune system is especially vulnerable to oxidative damage because many immune cells, such as neutrophils, produce reactive oxygen and nitrogen species (ROS and RNS) as part of the body's defence mechanisms to destroy invading pathogens. It is well known that the function of neutrophils is altered in diabetes; one of the major functional changes in neutrophils in diabetes is the increased generation of extracellular superoxide via the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system. The purpose of this study is to evaluate the production of ROS and nitric oxide (NO) as well as the expression of NADPH oxidase subunits, inducible nitric oxide (iNOS), superoxide dismutase (SOD) and catalase (CAT) in neutrophils from diabetic rats treated with annatto extract and β-carotene. Forty-eight female Fisher rats were distributed into six groups according to the treatment received. All animals were sacrificed 7 days after treatment, and the neutrophils were isolated using two gradients of different densities. The ROS and NO were quantified by a chemiluminescence and spectrophotometric assays, respectively. Analyses of gene expression were performed using quantitative real time polymerase chain reaction (qRT-PCR). The results show that treatment with annatto extract and β-carotene was able to decrease ROS production and the mRNA levels of p22(phox) and p47(phox) and increase the mRNA levels of SOD and CAT in neutrophils from diabetic rats. These data suggest that annatto extract and β-carotene exerts antioxidant effect via inhibition of expression of the NADPH oxidase subunits and increase expression/activity of antioxidant enzymes.
authors.affiliation: Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil.
authors.forename: Joamyr Victor
authors.initials: JV
authors.lastname: Rossoni Júnior
authors.forename: Glaucy Rodrigues
authors.initials: GR
authors.lastname: Araújo
authors.forename: Bruno Da Cruz
authors.initials: Bda C
authors.lastname: Pádua
authors.forename: Cíntia Lopes de Brito
authors.initials: CL
authors.lastname: Magalhães
authors.forename: Míriam Martins
authors.initials: MM
authors.lastname: Chaves
authors.forename: Maria Lúcia
authors.initials: ML
authors.lastname: Pedrosa
authors.forename: Marcelo Eustáquio
authors.initials: ME
authors.lastname: Silva
authors.forename: Daniela Caldeira
authors.initials: DC
authors.lastname: Costa
mesh_terms: D000496:Alloxan; D000818:Animals; D031212:Bixaceae; D002338:Carotenoids / Q000494:pharmacology*; D002374:Catalase / Q000096:biosynthesis / Q000235:genetics; D002478:Cells, Cultured / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000188:drug therapy* / Q000235:genetics / Q000276:immunology; D004353:Drug Evaluation, Preclinical; D005260:Female; D016166:Free Radical Scavengers / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D022781:Hepatocytes / Q000187:drug effects; D019255:NADPH Oxidases / Q000096:biosynthesis / Q000235:genetics; D009504:Neutrophils / Q000187:drug effects* / Q000201:enzymology; D009569:Nitric Oxide / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D011916:Rats, Inbred F344; D017382:Reactive Oxygen Species / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000096:biosynthesis / Q000235:genetics; D019207:beta Carotene / Q000494:pharmacology*
chemical_list: D016166:Free Radical Scavengers; D010936:Plant Extracts; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D019207:beta Carotene; D009569:Nitric Oxide; D002338:Carotenoids; C054041:annatto; D000496:Alloxan; D002374:Catalase; D013482:Superoxide Dismutase; D019255:NADPH Oxidases; C515768:Cyba protein, rat; C060505:neutrophil cytosolic factor 1