Cléia Rocha de Oliveira1, Juliana Ceolin2, Renata Rocha de Oliveira2, Elizângela Gonçalves Schemitt3, Josieli Raskopf Colares4, Liliane De Freitas Bauermann5, Ijone Hilda Costabeber6, Maria Isabel Morgan-Martins7, José L Mauriz8, Juliana Da Silva9, Juliana Moysés Reyes10, Norma Possa Marroni11. 1. Universidade Federal de Santa Maria. PPG BioSaúde/ULBRA.. fisio_cleia@hotmail.com. 2. Universidade Federal de Santa Maria.. fisio_cleia@hotmail.com. 3. Laboratório de Hepatologia e Gastroenterologia Experimental/HCPA. Laboratório de Estresse Oxidativo e Antioxidantes/ULBRA.. elizschemitt@yahoo.com.br. 4. Laboratório de Hepatologia e Gastroenterologia Experimental/HCPA. Laboratório de Estresse Oxidativo e Antioxidantes/ULBRA. PPG BioSaúde/ULBRA.. jozy.ma@hotmail.com. 5. Laboratório de Fisiologia/UFSM.. fisio_cleia@hotmail.com. 6. Laboratório de Pesticidas Persistentes - LAPP/UFSM.. fisio_cleia@hotmail.com. 7. Laboratório de Hepatologia e Gastroenterologia Experimental/HCPA. Laboratório de Estresse Oxidativo e Antioxidantes/ULBRA.. morganmartins@terra.com.br. 8. Institute of Biomedicine (IBIOMED). University of Leon. Spain.. jl.mauriz@unileon.es. 9. Laboratório de Hepatologia e Gastroenterologia Experimental/HCPA. Laboratório de Estresse Oxidativo e Antioxidantes/ULBRA. PPG Fisiologia/UFRGS. PPG Ciências Médicas/UFRGS. PPG BioSaúde/ULBRA.. 10. PPG BioSaúde/ULBRA.. 11. PPG BioSaúde/ULBRA.. nmarroni@terra.com.br.
Abstract
INTRODUCTION: Polychlorinated biphenyls (PCBs), used as pesticides in agriculture, can lead to irreversible injuries in living organisms, particularly in liver. Oxidative stress has been implicated in the liver pathogenesis induced by different molecules, including PCBs. It has been demonstrated that quercetin, an antioxidant flavonoid found in the diet, exhibits a potent antioxidant effect in different liver pathologies. OBJECTIVE: To evaluate oxidative stress caused by PCBs in liver and the antioxidant activity of quercetin. METHODOLOGY: We used male Wistar rats (n = 36), divided in 4 groups: control, quercetin (50 mg/kg/day), PCBs (0.4 ml/kg/day), and rats treated with both PCBs and quercetin. On day 25 blood was collected to assess liver integrity (enzymes AST, ALT and ALP), and liver samples to measure oxidative stress (TBARS), activity of antioxidant enzymes (SOD, CAT, GPx) and DNA damage (micronucleus assay), and histological damage. RESULTS: TBARS concentration and SOD activity were significantly higher in PCBs animals as compared to the PCB group receiving quercetin. CAT and GPx decreased in PCBs and increased when quercetin was added. The histological analysis showed damage to hepatocytes in PCBs, but quercetin was able to afford protection against such damage. The micronucleus test showed there was an increase in the production of microclenucleus compared to control, and quercetin was able to reduce this effect. CONCLUSION: Contamination with PCBs led to increased lipid peroxidation and DNA damage, and the use of antioxidant quercetin was effective in reducing PCBs-induced liver injury. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
INTRODUCTION:Polychlorinated biphenyls (PCBs), used as pesticides in agriculture, can lead to irreversible injuries in living organisms, particularly in liver. Oxidative stress has been implicated in the liver pathogenesis induced by different molecules, including PCBs. It has been demonstrated that quercetin, an antioxidant flavonoid found in the diet, exhibits a potent antioxidant effect in different liver pathologies. OBJECTIVE: To evaluate oxidative stress caused by PCBs in liver and the antioxidant activity of quercetin. METHODOLOGY: We used male Wistar rats (n = 36), divided in 4 groups: control, quercetin (50 mg/kg/day), PCBs (0.4 ml/kg/day), and rats treated with both PCBs and quercetin. On day 25 blood was collected to assess liver integrity (enzymes AST, ALT and ALP), and liver samples to measure oxidative stress (TBARS), activity of antioxidant enzymes (SOD, CAT, GPx) and DNA damage (micronucleus assay), and histological damage. RESULTS:TBARS concentration and SOD activity were significantly higher in PCBs animals as compared to the PCB group receiving quercetin. CAT and GPx decreased in PCBs and increased when quercetin was added. The histological analysis showed damage to hepatocytes in PCBs, but quercetin was able to afford protection against such damage. The micronucleus test showed there was an increase in the production of microclenucleus compared to control, and quercetin was able to reduce this effect. CONCLUSION: Contamination with PCBs led to increased lipid peroxidation and DNA damage, and the use of antioxidant quercetin was effective in reducing PCBs-induced liver injury. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.