The Protective Effect of N-Acetylcysteine on Oxidative Stress in the Brain Caused by the Long-Term Intake of Aspartame by Rats

Long-term intake of aspartame at the acceptable daily dose causes oxidative stress in rodent brain mainly due to the dysregulation of glutathione (GSH) homeostasis. N-Acetylcysteine provides the cysteine that is required for the production of GSH, being effective in treating disorders associated with oxidative stress. We investigated the effects of N-acetylcysteine treatment (150 mg kg(-1), i.p.) on oxidative stress biomarkers in rat brain after chronic aspartame administration by gavage (40 mg kg(-1)). N-Acetylcysteine led to a reduction in the thiobarbituric acid reactive substances, lipid hydroperoxides, and carbonyl protein levels, which were increased due to aspartame administration. N-Acetylcysteine also resulted in an elevation of superoxide dismutase, glutathione peroxidase, glutathione reductase activities, as well as non-protein thiols, and total reactive antioxidant potential levels, which were decreased after aspartame exposure. However, N-acetylcysteine was unable to reduce serum glucose levels, which were increased as a result of aspartame administration. Furthermore, catalase and glutathione S-transferase, whose activities were reduced due to aspartame treatment, remained decreased even after N-acetylcysteine exposure. In conclusion, N-acetylcysteine treatment may exert a protective effect against the oxidative damage in the brain, which was caused by the long-term consumption of the acceptable daily dose of aspartame by rats.Fil: Finamor, Isabela A.. Universidade Federal de Santa Maria; BrasilFil: Ourique, Giovana M.. Universidade Federal de Santa Maria; BrasilFil: Pês, Tanise S.. Universidade Federal de Santa Maria; BrasilFil: Saccol, Etiane M. H.. Universidade Federal de Santa Maria; BrasilFil: Bressan, Caroline A.. Universidade Federal de Santa Maria; BrasilFil: Scheid, Taína. Universidade Federal do Rio Grande do Sul; BrasilFil: Baldisserotto, Bernardo. Universidade Federal de Santa Maria; BrasilFil: Llesuy, Susana Francisca. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Partata, Wânia A.. Universidade Federal do Rio Grande do Sul; BrasilFil: Pavanato, Maria A.. Universidade Federal do Rio Grande do Sul; Brasi

Quercetin attenuates endocrine and metabolic responses to oxytetracycline in silver catfish (Rhamdia quelen)

This study aimed to verify whether dietary quercetin protects against the detrimental effects induced by oxytetracycline (OTC) administration in silver catfish (Rhamdia quelen). Fish were divided into different experimental groups that received OTC and/or quercetin, either during 14 or 21 days. To determine the endocrine system stress response, we have measured the brain mRNA expression levels of corticotropin-releasing hormone (crh), proopiomelanocortins (pomca and pomcb) and some of the pituitary hormones (growth hormone [gh], somatolactin [sl], and prolactin [prl]). We have also quantified the levels of cortisol as well as some metabolites (glucose, glycogen, lactate, and triglycerides) in the plasma. Moreover, the enzymatic activity of hexokinase, phosphorylase (active GPase), fructose-biphosphatase (FBP), glycerol-3-phosphate dehydrogenase, glucose-6-phosphate dehydrogenase, and glutamate dehydrogenase (GDH) and gill Na+/K+-ATPase were measured. The results demonstrated that OTC activates the silver catfish stress response by increasing the plasma cortisol and decreasing the glucose levels at 14 and 21 days. Additionally, OTC also altered the fish hepatic metabolic status as demonstrated by an increase in triglycerides levels and the enzymatic activity of both FBP and GDH after 14 days. OTC also stimulated Na+/K+-ATPase activity in the gill after 14 days and altered the hypophyseal expression of gh (at 14 and 21 days) and prl (at 14 days). The co-treatment with 1.5 g of quercetin could prevent most of the alterations caused by OTC, strongly suggesting quercetin as a beneficial compound when added to the fish diet.This work was funded by Spanish Ministry of Science and Innovation - MICINN (AGL2016-76069-C2-1-R) awarded to JMM. IJC was supported by a contract from the University of Cádiz (PIF UCA/REC02VIT/2014; 2018-011/PU/AY.PUENTE/CD). The authors (IJC and JMM) belong to the Fish Welfare and Stress Network (AGL2016-81808-REDT), which is supported by the Agencia Estatal de Investigación (MICINN, Spanish Government). The authors wish to thank the financial support received by Conselho Nacional de Pesquisa e Desenvolvimento Científico-CNPq (Ministry of Education of Brazil, Brazil) through the program CSF (Programa Ciência sem Fronteiras (CONCF) - Process: 207329/2015-0) awarded to Tanise da Silva Pês and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effects of parboiled rice diet on oxidative stress parameters in kidney of rats with streptozotocin-induced diabetes

The effect of parboiled rice (PR) and white rice (WR) diets on oxidative stress (OS) parameters was investigated in the kidneys of rats with streptozotocin-induced diabetes (40mg kg-1, iv). The experimental groups (n=8) were control fed with PR (CPR), control fed with WR, diabetic fed with PR, and diabetic fed with WR. After 30 days of treatment, all animals were anesthetized and exsanguinated before removal of kidneys, which were used to determine thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides, carbonyl protein, superoxide dismutase, catalase, glutathione peroxidase (GPx), glutathione reductase, glutathione-S-transferase activities, and levels of glutathione (GSH). Total phenolic compounds were determined in WR and PR grains. Our data indicated that diabetes induced increase in TBARS and lipid hydroperoxides levels. Although PR has not prevented the rise in the levels of these measurements, its consumption by our animals resulted in higher GPx activity and GSH content than that of the CPR. Moreover, PR also presented concentration of total phenolic compounds 127% higher than WR grains. Thus, its consumption in this diabetic condition is suggested because this seems to confer greater protection against OS in the renal tissue of diabetic animals. © Copyright 2012, Mary Ann Liebert, Inc.Fil: Finamor, Isabela A.. Federal University of Santa Maria; BrasilFil: Saccol, Etiane M. H.. Federal University of Santa Maria; BrasilFil: Gabriel, Diogo. Federal University of Santa Maria; BrasilFil: Ourique, Giovana M.. Federal University of Santa Maria; BrasilFil: Riffel, Ana P.K.. Federal University of Santa Maria; BrasilFil: Konrad, Signorá P.. University of Vale do Rio dos Sinos; BrasilFil: Belló Klein, Adriane. Universidade Federal do Rio Grande do Sul; BrasilFil: Partata, Wania. Universidade Federal do Rio Grande do Sul; BrasilFil: Baldisserotto, Bernardo. Federal University of Santa Maria; BrasilFil: Llesuy, Susana Francisca. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; ArgentinaFil: Pavanato, Maria A.. Federal University of Santa Maria; Brasi

Myrcia sylvatica essential oil mitigates molecular, biochemical and physiological alterations in Rhamdia quelen under different stress events associated to transport

The effects of pre-transport handling and addition of essential oil of Myrcia sylvatica (EOMS) during transport on stress pathways activation in Rhamdia quelen were investigated. Fish (n = 400, 25.2 ± 2.9 g) were captured in production ponds and transferred to 100-L tank (density 100 g L− 1). After 24 h, 10 fish were sampled (before transport group). The remaining fish were placed in plastic bags (n = 30 or 32 fish per bag, density 150 g L− 1) containing 5 L of water (control), ethanol (315 μL L− 1, vehicle) or EOMS (25 or 35 μL L− 1), in triplicate, transported for 6 h and sampled (n = 10 animals per group). Indicators of stress and metabolism, as well as mRNA expression of brain hormones were evaluated. Previously, full-length cDNAs, encoding specific corticotropin-releasing hormone (crh) and proopiomelanocortins (pomca and pomcb), were cloned from whole brain of R. quelen. Crh expression increased after 24 h of capture and handling, whereas cortisol and glucose plasmatics enhanced their values in the control group. Transport with EOMS reduced plasma cortisol and lactate levels, while ethanol and EOMS groups increased Na+/K+-ATPase gill activity compared to control. Gene expression of crh, pomcb, prolactin and somatolactin mRNAs were lower after transport with EOMS compared to control. EOMS was able to mitigate the stress pathways activation caused by transport, maintaining a balance in body homeostasis. Thus, EOMS is recommended as sedative in procedures as transport and the pre-transport handling requires greater attention and use of tranquilizersWe would also like to thank the financial support received by CAPES (Ministry of Education of Brazil, Brazil) through the program PDSE-CAPES (Programa Institucional de Bolsas de Doutorado Sanduíche no Exterior - Process: 5055/14-8) awarded to E.M.H.S.; the CNPq research fellowship awarded to B.B., project ADAPTA II (process number 465540/2014-7 CNPq) and the project AGL2013-48835-C2-R (Ministry of Science and Education, Spain) awarded to J.M.M. J.A.M-S is currently funded by a Postdoctoral Research Fellowship (Juan de la Cierva-Formación, Reference FJCI-2014-20161) from the Spanish Ministry of Education, Economy and Competitiveness (MINECO).Peer reviewe

Humic acid and moderate hypoxia alter oxidative and physiological parameters in different tissues of silver catfish (Rhamdia quelen)

Aquatic animals are naturally exposed simultaneously to environments with different concentrations of humic acid (HA) and seasonal or daily variations of dissolved oxygen (DO) levels. This study investigated the effects of simultaneous exposure to different HA and DO levels on plasma ion levels and some hematological and oxidative parameters in different tissues of silver catfish (Rhamdia quelen). The fish were exposed to 0, 2.5 or 5 mg L(-1) HA for 120 h. After this period, each group was divided into two groups: normoxia and hypoxia. Exposure to the different DO levels lasted 96 h, totaling 216 h of experimentation. At the end of the experimental period, blood sampling was performed, and the fish were euthanized prior to the excision of the gills and the brain to evaluate hematological and oxidative parameters. To verify the antioxidant capacity of HA, total phenolic compounds were measured. In general, all tissues of silver catfish exposed simultaneously to hypoxia and different HA concentrations showed a reduction in lipid peroxidation levels, as well as a modulation of the antioxidant system. These effects occurred in an HA concentration-dependent manner. Thus, HA is beneficial to silver catfish exposed to hypoxia. These beneficial effects can be attributed, most likely, to the action of the different HA constituents and functional groups, including phenolic compounds, which have antioxidant properties.Fil: Riffel, Ana P. K.. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; BrasilFil: Saccol, Etiane M. H.. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; BrasilFil: Finamor, Isabela A.. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; BrasilFil: Ourique, Giovana M.. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; BrasilFil: Gressler, Luciane T.. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; BrasilFil: Parodi, Thaylise V.. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; BrasilFil: Goulart, Luis O. R.. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; BrasilFil: Llesuy, Susana Francisca. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Baldisserotto, Bernardo. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; BrasilFil: Pavanato, María A.. Universidade Federal de Santa Maria. Departamento de Fisiologia e Farmacologia; Brasi

Effects of subchronic manganese chloride exposure on tambaqui (Colossoma macropomum) tissues: oxidative stress and antioxidant defenses.

This study aimed to evaluate oxidative stress parameters in juvenile tambaqui (Colossoma macropomum) exposed to 3.88 mg l−1 Mn2+ for 96 hours. Biomarkers of oxidative stress, such as thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), and glutathione-S-transferase (GST) activities, as well as content of reduced glutathione (GSH), were analyzed in gill, liver, brain, and kidney. The presence of Mn2+ in the water corresponded to increased levels of Mn2+ accumulation according to the following sequence: gill > kidney > brain > liver. There was a significant increase in TBARS levels (40 %) and SOD activity (80 %) in addition to a significant decrease in GSH content (41 %) in gills of fish exposed to waterborne Mn2+. In hepatic tissue of the exposed animals, TBARS levels decreased significantly (35 %), whereas SOD (82 %) and GST activities (51 %) as well as GSH content (43 %) increased significantly. In brain of exposed juvenile fish, only significant decreases in SOD (32 %) and CAT activities (65 %) were observed. Moreover, the kidney of exposed fish showed a significant increase in TBARS levels (53 %) and a significant decrease in SOD activity (41 %) compared with the control. Thus, the changes in biomarkers of oxidative stress were different in the tissues, showing a specific toxicity of this metal to each organ.Fil: Gabriel, Diogo. University of Santa Maria; BrasilFil: Riffel, Ana Paula K.. University of Santa Maria; BrasilFil: Finamor, Isabella A.. University of Santa Maria; BrasilFil: Saccol, Etiane M. H.. University of Santa Maria; BrasilFil: Ourique, Giovana M.. University of Santa Maria; BrasilFil: Goulart, Luis O.. University of Santa Maria; BrasilFil: Kochhann, Daiani. National Institute for Research in the Amazon; BrasilFil: Cunha, Mauro A. . University of Santa Maria; BrasilFil: Garcia, Luciano O.. Universidade Federal do Rio Grande do Sul; BrasilFil: Pavanato, María A.. University of Santa Maria; BrasilFil: Val, Adalberto Val. National Institute for Research in the Amazon; BrasilFil: Baldisserotto, Bernardo. University of Santa Maria; BrasilFil: Llesuy, Susana Francisca. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentin