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2.
Life Sci ; 91(19-20): 907-11, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-22982469

RESUMO

AIM: Oxidative stress, observed in the asthmatic airways, is not localized only to the bronchial system. It would be a great advantage to monitor the oxidative stress markers from blood especially in childhood asthma following the inflammation. Our aim was to measure the levels of antioxidants and the oxidatively damaged biomolecules. We were also interested in the gene expression alterations of the free radical source gp91(phox) subunit (CYBB) of the NADPH oxidase system, and the antioxidant heme oxygenase-1 (HMOX-1) isoenzyme in the blood. Our findings were also examined in the context of medical treatment. MAIN METHODS: Oxidative stress parameters via photometric methods, CYBB and HMOX-1 expressions via real-time PCR were measured in 58 asthmatic and 30 healthy children. KEY FINDINGS: Higher blood thiobarbituric acid reactive substances (TBARS) (p<0.03) and carbonylated protein (p<0.05) levels were found in the asthmatic children than in the controls. The relative expression of CYBB was significantly lower (p<0.05) in patients treated with a low daily dose of inhaled corticosteroid (ICS), than in asthmatics not receiving ICS therapy. Higher ICS doses alone or combined with long acting ß2-receptor agonists did not influence the expression significantly. No similar tendency was found as regards to HMOX-1 expression. SIGNIFICANCE: Elevated levels of damaged lipid (TBARS) and protein (carbonylated) products corroborate the presence of oxidative stress in the blood during bronchial asthma and suggest the presence of chronic oxidative overload. Our findings also suggest that ICS treatment can influence the relative CYBB mRNA expression in circulating leukocytes in a dose dependent manner.


Assuntos
Asma/tratamento farmacológico , Glucocorticoides/farmacologia , Glicoproteínas de Membrana/metabolismo , NADPH Oxidases/metabolismo , Estresse Oxidativo , Administração por Inalação , Adolescente , Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Regulação da Expressão Gênica , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Leucócitos/metabolismo , Masculino , Glicoproteínas de Membrana/genética , NADPH Oxidase 2 , NADPH Oxidases/genética , Reação em Cadeia da Polimerase , Carbonilação Proteica , RNA Mensageiro/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
3.
Ecotoxicol Environ Saf ; 72(5): 1337-42, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19423166

RESUMO

Cadmium, known as a non-essential heavy metal, can cause oxidative stress in plants. In this study we tried to find out whether oxidative changes could be measured in the early stages of ontogenesis in Indian mustard (Brassica juncea L.) seeds exposed to Cd stress. Cadmium-caused oxidative stress and antioxidative responses were investigated with respect to both time- and concentration-dependence. Parameters that were measured were follows: total antioxidant capacity (ferric reducing ability of plasma (FRAP)), glutathione (GSH) content, level of lipid peroxidation (LP), total protein content, and glutathione-S-transferase (GST, EC 2.5.1.18) activity. Seeds were germinated in vitro at 0, 50, 100 and 200mg/LCd concentrations in dark for 12, 24, 48 and 96h. Oxidative stress occurred in the seeds due to Cd treatment, the level of LP was high at the beginning of the germination at all concentrations used, but it attenuated later on. FRAP showed concentration-dependent increase during 24h, but it decreased later on. GSH content was also elevated by increasing concentrations of Cd, which referred to the activity of non-enzymatic antioxidant system. The GST activity induced with germination only after 24h at the highest Cd concentration. The results show that FRAP is a suitable parameter with which to assess the antioxidant capacity of heavy metal-stressed germinating seeds.


Assuntos
Antioxidantes/metabolismo , Cloreto de Cádmio/toxicidade , Germinação , Mostardeira/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sementes/efeitos dos fármacos , Poluentes do Solo/toxicidade , Cloreto de Cádmio/metabolismo , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Mostardeira/metabolismo , Oxirredução , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Poluentes do Solo/metabolismo , Fatores de Tempo
4.
World J Gastroenterol ; 10(14): 2082-6, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15237439

RESUMO

AIM: To assess the role of oxygen-derived free radicals and cytokines in the pathogenesis of taurocholic acid-induced acute pancreatitis, and to evaluate the preventive effects of octreotide towards the development of acute pancreatitis. METHODS: Acute pancreatitis was induced in male New Zealand white rabbits by retrograde injection of 0.8 mL/kg.b.m. of 50 g/L sodium taurocholate (NaTC) in the pancreatic duct. Sham-operated animals served as control. Octreotide 1 mg/kg.b.m. was administered subcutaneously before the induction of pancreatitis. Blood was taken from the jugular vein before and at 1, 3, 6, 12 and 24 h after pancreatitis induction. Serum activities of amylase, IL-6 and TNF-alpha and levels of malonyl dialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPx), catalase and superoxide dismutase (Mn-, Cu-, and Zn-SOD) in pancreatic tissue were measured. RESULTS: Serum TNF-alpha and IL-6 levels increased significantly 3 h after the onset of pancreatitis, and then returned to control level. The tissue concentration of MDA was significantly elevated at 24 h, while the GSH level and GP-x, catalase, Mn-SOD, Cu-, Zn-SOD activities were all significantly decreased in animals with pancreatitis as compared to the control. Octreotide pretreatment significantly reversed the changes in cytokines and reactive oxygen metabolites. Octreotide treatment did not alter the serum amylase activity and did not have any beneficial effects on the development of histopathological changes. CONCLUSION: Oxygen-derived free radicals and proinflammatory cytokines are generated at an early stage of NaTc-induced acute pancreatitis in rabbits. Prophylactic octreotide treatment can prevent release of cytokines and generation of reactive oxygen metabolites, but does not have any beneficial effects on the development of necrotizing pancreatitis.


Assuntos
Octreotida/farmacologia , Pancreatite Necrosante Aguda/prevenção & controle , Animais , Citocinas/antagonistas & inibidores , Masculino , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Pancreatite Necrosante Aguda/induzido quimicamente , Pancreatite Necrosante Aguda/patologia , Coelhos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Ácido Taurocólico
5.
Eur J Obstet Gynecol Reprod Biol ; 103(2): 136-9, 2002 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-12069735

RESUMO

OBJECTIVES: To investigate the antioxidant defense potential of human neonates according to gestational age and mode of delivery. STUDY DESIGN: Four study groups were established, full-term normal spontaneous vaginal delivery (FT-NSVD, n=24), full-term caesarean section (FT-CS, n=19), preterm normal spontaneous vaginal delivery (PT-NSVD, n=15) preterm caesarean section (PT-CS, n=21). The activity of catalase (CAT), glutathion peroxidase (GPX), Cu/Zn superoxide dismutase (Cu/Zn-SOD) were determined from cord blood. Statistical analysis was made by ANOVA. RESULTS: CAT activity was significantly higher in full-term than in preterm newborns. In both the categories, neonates born via caesarean section had significantly lower CAT activities. GPX activity was significantly higher in the FT-NSVD group than in any other group. Cu/Zn-SOD activity was significantly higher in full-term neonates than in preterms and no difference was found related to the mode of delivery. CONCLUSIONS: Prematurity and caesarean section may cause a deficiency of antioxidant defense in human newborn.


Assuntos
Antioxidantes/metabolismo , Cesárea , Enzimas/sangue , Recém-Nascido Prematuro/metabolismo , Catalase/sangue , Parto Obstétrico , Feminino , Glutationa Peroxidase/sangue , Humanos , Recém-Nascido/metabolismo , Gravidez , Valores de Referência , Superóxido Dismutase/sangue
6.
Pancreas ; 24(1): 83-9, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11741186

RESUMO

INTRODUCTION: Heat shock proteins (HSPs) have indispensable functions in the synthesis, degradation, folding, transport, and translocation of intracellular proteins. HSPs are proteins that help cells to survive stress conditions by repairing damaged proteins. AIM: To investigate the potential effects of HSP preinduction by cold-water (CWI) or hot-water immersion (HWI) on sodium taurocholate (TC)-induced acute pancreatitis in rats. METHODOLOGY: TC was injected into the common biliopancreatic duct of the animals at the peak level of HSP synthesis, as determined by Western blot analysis. The rats were killed by exsanguination through the abdominal aorta 6 hours after the TC injection. The serum amylase activity, the IL-1, IL-6 and TNF-alpha levels, the pancreatic weight/body weight ratio, and the pancreatic contents of DNA, protein, amylase, lipase, and trypsinogen were measured, and a biopsy for histology was taken. RESULTS: HWI significantly elevated HSP72 expression, whereas CWI significantly increased HSP60 expression. It was demonstrated that CWI pretreatment ameliorated the pancreatic edema and the serum amylase level increase, whereas the morphologic damage was more severe in this form of acute pancreatitis. HWI pretreatment did not have any effects on the measured parameters in TC-induced pancreatitis. CONCLUSIONS: The findings suggest a possible role of HSP60, but not HSP72, in the slight protection in the early phase of this necrohemorrhagic pancreatitis model.


Assuntos
Pancreatite/metabolismo , Pancreatite/patologia , Amilases/sangue , Animais , Peso Corporal , Chaperonina 60/análise , Citocinas/sangue , DNA/análise , Modelos Animais de Doenças , Febre/metabolismo , Proteínas de Choque Térmico HSP72 , Proteínas de Choque Térmico/análise , Hipotermia/metabolismo , Lipase/análise , Masculino , Tamanho do Órgão , Pâncreas/patologia , Pancreatite/induzido quimicamente , Ratos , Ratos Wistar , Ácido Taurocólico , Tripsinogênio/análise
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