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1.
Pan Afr Med J ; 33: 187, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31565147

RESUMO

Fumonisin B1 (FB1) is a mycotoxin frequently found in agricultural commodities. The toxin poses a considerable risk for human and animal health. FB1 is among several mycotoxins produced by Fusarium spp. contaminating virtually any cereal and other Poaceae. Their intracellular action includes the promotion of oxidative stress through the generation of reactive oxygen species (ROS) that damage biomolecules such as DNA. These toxic effects were observed in vivo and in vitro. However, the association between esophageal lesions and oxidative stress induced by FB1. Studies in China, Iran and South Africa showed higher exposure to fumonisins in areas with higher risk of esophageal cancer (EC). Exposure to mycotoxins may be inevitable in Mozambique. How mycotoxins, particularly fumonisins from the contaminated food, can be associated with the emergence of EC in Mozambique? Herein, we revise the literature and present some pieces of evidence in order to highlight the burden of mycotoxins and to provide evidence-based considerations for the stakeholders involved in the management of the EC agenda in Mozambique. The information presented herein supports the need to implement novel and/or to revisit the existent detoxification methods to reduce the global burden of mycotoxins and its outcomes in health management.


Assuntos
Carcinógenos Ambientais/toxicidade , Neoplasias Esofágicas/epidemiologia , Fumonisinas/toxicidade , Micotoxinas/toxicidade , Animais , Neoplasias Esofágicas/etiologia , Contaminação de Alimentos/prevenção & controle , Fusarium/metabolismo , Humanos , Moçambique/epidemiologia , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo
2.
Acta Cir Bras ; 34(7): e201900707, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31531528

RESUMO

PURPOSE: To evaluate the effects of splenic ischemic preconditioning (sIPC) on oxidative stress induced by hepatic ischemia-reperfusion in rats. METHODS: Fifteen male Wistar rats were equally divided into 3 groups: SHAM, IRI and sIPC. Animals from IRI group were subjected to 45 minutes of partial liver ischemia (70%). In the sIPC group, splenic artery was clamped in 2 cycles of 5 min of ischemia and 5 min of reperfusion (20 min total) prior to hepatic ischemia. SHAM group underwent the same surgical procedures as in the remaining groups, but no liver ischemia or sIPC were induced. After 1h, hepatic and splenic tissue samples were harvested for TBARS, CAT, GPx and GSH-Rd measurement. RESULTS: sIPC treatment significantly decreased both hepatic and splenic levels of TBARS when compared to IRI group (p<0.01). Furthermore, the hepatic and splenic activities of CAT, GPx and GSH- Rd were significantly higher in sIPC group than in IRI group. CONCLUSION: sIPC was able to attenuate hepatic and splenic IRI-induced oxidative stress.


Assuntos
Precondicionamento Isquêmico/métodos , Hepatopatias/prevenção & controle , Fígado/irrigação sanguínea , Estresse Oxidativo/fisiologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Fígado/fisiologia , Hepatopatias/fisiopatologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Traumatismo por Reperfusão/fisiopatologia
3.
Pestic Biochem Physiol ; 159: 1-8, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400771

RESUMO

We examined the molecular regulation of porphyrin biosynthesis and protective responses in transgenic rice (Oryza sativa) expressing Bradyrhizobium japonicum Fe-chelatase (BjFeCh) after treatment with acifluorfen (AF). During the photodynamic stress imposed by AF, transcript levels of BjFeCh in transgenic plants increased greatly; moreover, transcript levels of OsFeCh2 remained almost constant, whereas in wild type (WT) plants they were considerably down-regulated. In the heme branch, transgenic plants exhibited greater levels of OsFC and HO transcripts than WT plants in the untreated stems as well as in the AF-treated leaves and stems. Both WT and transgenic plants treated with AF substantially decreased transcript levels for all the genes in the chlorophyll branch, with less decline in transgenic plants. After AF treatment, ascorbate (Asc) content and the redox Asc state greatly decreased in leaves of WT plants; however, in transgenic plants both parameters remained constant in leaves and the Asc redox state increased by 20% in stems. In response to AF, the leaves of WT plants greatly up-regulated CatA, CatB, and GST compared to those of transgenic plants, whereas, in the stems, transgenic plants showed higher levels of CatA, CatC, APXb, BCH, and VDE. Photochemical quenching, qP, was considerably dropped by 31% and 18% in WT and transgenic plants, respectively in response to AF, whereas non-radiative energy dissipation through non-photochemical quenching increased by 77% and 38% in WT and transgenic plants, respectively. Transgenic plants treated with AF exhibited higher transcript levels of nucleus-encoded photosynthetic genes, Lhcb1 and Lhcb6, as well as levels of Lhcb6 protein compared to those of WT plants. Our study demonstrates that expression of BjFeCh in transgenic plants influences not only the regulation of porphyrin biosynthesis through maintaining higher levels of gene expression in the heme branch, but also the Asc redox function during photodynamic stress caused by AF.


Assuntos
Proteínas de Bactérias/metabolismo , Bradyrhizobium/enzimologia , Ferroquelatase/metabolismo , Nitrobenzoatos/farmacologia , Oryza/metabolismo , Porfirinas/biossíntese , Proteínas de Bactérias/genética , Ferroquelatase/genética , Regulação da Expressão Gênica de Plantas , Oryza/genética , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Plantas Geneticamente Modificadas
4.
Braz J Med Biol Res ; 52(8): e8688, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31389493

RESUMO

The objective of this study was to investigate the effect of whole body vibration (WBV) exercise on oxidative stress markers in a group of women with fibromyalgia (FM) compared to a group of healthy women (CT). Twenty-one women diagnosed with FM and 21 age- and weight-matched healthy women were enrolled the study. Plasma oxidative stress markers (primary outcomes) were evaluated at rest and after WBV, and included thiobarbituric acid reactive substances (TBARS), iron reduction capacity (FRAP), superoxide dismutase antioxidant enzymes activity (SOD), and catalase (CAT). At rest, the FM group had higher TBARS (P<0.001) and FRAP (P<0.001), and lower CAT (P=0.005) compared to the CT. In the CT group, the WBV had no effect on TBARS (P=0.559) and FRAP (P=0.926), whereas it increased both SOD (P<0.001) and CAT (P<0.001). In the FM group, the WBV reduced TBARS (p <0.001), FRAP (P<0.001), and CAT (P=0.005), while it increased SOD (P=0.019). There was an interaction effect (moments vs groups) in the TBARS (effect size=1.34), FRAP (effect size=0.93), CAT (effect size=1.45), and SOD (effect size=1.44) (P<0.001). A single trial of WBV exercise improved all oxidant and antioxidant parameters towards a greater adaptation to the stress response in FM women.


Assuntos
Biomarcadores/sangue , Fibromialgia/sangue , Estresse Oxidativo/fisiologia , Vibração , Estudos de Casos e Controles , Feminino , Fibromialgia/fisiopatologia , Humanos , Pessoa de Meia-Idade
5.
An Acad Bras Cienc ; 91(3): e20180395, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31432900

RESUMO

The aquatic environment presents daily and/or seasonal variations in dissolved oxygen (DO) levels. Piava faces different DO levels in the water due to its distributional characteristics. The goal of this study was to describe the effects of low DO levels on plasma ion, biochemical and oxidative variables in piava juveniles. Fish were exposed to different DO levels, including 1.0, 2.0, 3.0, 4.0 and 5.0 mg L-1 of DO for 96 h, after which blood and tissue samples (liver, kidney, gill and muscle) were collected. The decrease in DO levels decreased plasma Na+, Cl-, K+ and NH3 levels as well as protein and glycogen levels in the liver, kidney and muscle; increased Na+/K+-ATPase activity in the gills and kidney as well as glucose and ammonia levels in the liver, kidney and muscle; and increased lactate levels in the kidney and muscle. Thiobarbituric acid-reacting substances, catalase and non-protein thiol levels decreased in the tissues of piavas exposed to low DO levels. It is concluded that piava can apparently cope with hypoxic conditions; however, low DO levels are a stressor, and the tolerance of piava to hypoxia involves iono-regulatory, metabolic and oxidative adjustments.


Assuntos
Adaptação Fisiológica/fisiologia , Caraciformes/fisiologia , Estresse Oxidativo/fisiologia , Oxigênio/fisiologia , Animais , Catalase/metabolismo , Caraciformes/metabolismo , Ácido Láctico/metabolismo , Oxigênio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Superóxido Dismutase/metabolismo
6.
Exp Parasitol ; 205: 107748, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31442453

RESUMO

Trypanosoma cruzi (the causative agent of Chagas disease) presents a complex life cycle that involves adaptations in vertebrate and invertebrate hosts. As a protozoan parasite of hematophagous insects and mammalian hosts, T. cruzi is exposed to reactive oxygen species (ROS). To investigate the functionality of T. cruzi tartrate-resistant acid phosphatase type 5 (TcACP5), we cloned, superexpressed and purified the enzyme. Purified TcACP5 exhibited a Vmax and apparent Km for pNPP hydrolysis of 7.7 ±â€¯0.2 nmol pNP × µg-1 × h-1 and 169.3 ±â€¯22.6 µM, respectively. The pH dependence was characterized by sharp maximal activity at pH 5.0, and inhibition assays demonstrated its sensitivity to acid phosphatase inhibitors. Similar activities were obtained with saturating concentrations of P-Ser and P-Thr as substrates. The enzyme metabolizes hydrogen peroxide (H2O2) in vitro, and parasites superexpressing this enzyme were more resistant to oxidative stress promoted by H2O2. Taken together, these results suggest that TcACP5 plays a central role in phosphoryl transfer and redox reactions.


Assuntos
Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo/fisiologia , Fosfatase Ácida Resistente a Tartarato/metabolismo , Trypanosoma cruzi/enzimologia , Sequência de Aminoácidos , Imunofluorescência , Regulação Enzimológica da Expressão Gênica , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Microscopia Confocal , Oxirredução , Especificidade por Substrato , Fosfatase Ácida Resistente a Tartarato/antagonistas & inibidores , Fosfatase Ácida Resistente a Tartarato/química , Transfecção , Trypanosoma cruzi/efeitos dos fármacos
7.
Eur J Epidemiol ; 34(9): 853-861, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31399939

RESUMO

Intake of individual antioxidants has been related to a lower risk of type 2 diabetes. However, the overall diet may contain many antioxidants with additive or synergistic effects. Therefore, we aimed to determine associations between total dietary antioxidant capacity and risk of type 2 diabetes, prediabetes and insulin resistance. We estimated the dietary antioxidant capacity for 5796 participants of the Rotterdam Study using a ferric reducing ability of plasma (FRAP) score. Of these participants, 4957 had normoglycaemia and 839 had prediabetes at baseline. We used covariate-adjusted proportional hazards models to estimate associations between FRAP and risk of type 2 diabetes, risk of type 2 diabetes among participants with prediabetes, and risk of prediabetes. We used linear regression models to determine the association between FRAP score and insulin resistance (HOMA-IR). We observed 532 cases of incident type 2 diabetes, of which 259 among participants with prediabetes, and 794 cases of incident prediabetes during up to 15 years of follow-up. A higher FRAP score was associated with a lower risk of type 2 diabetes among the total population (HR per SD FRAP 0.84, 95% CI 0.75; 0.95) and among participants with prediabetes (HR 0.85, 95% CI 0.73; 0.99), but was not associated with risk of prediabetes. Dietary FRAP was also inversely associated with HOMA-IR (ß - 0.04, 95% CI - 0.06; - 0.03). Effect estimates were generally similar between sexes. The findings of this population-based study emphasize the putative beneficial effects of a diet rich in antioxidants on insulin resistance and risk of type 2 diabetes.


Assuntos
Antioxidantes/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta , Resistência à Insulina , Avaliação Nutricional , Estado Pré-Diabético/metabolismo , Adulto , Idoso , Antioxidantes/administração & dosagem , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Frutas , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Estado Pré-Diabético/sangue , Estado Pré-Diabético/epidemiologia , Fatores de Risco
8.
Khirurgiia (Mosk) ; (6): 73-79, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31317944

RESUMO

The purpose of the study is to establish the effectiveness of remaxol in the correction of endogenous intoxication in patients with acute peritonitis. MATERIAL AND METHODS: The work is based on the results of clinical and laboratory studies. The clinic examined 55 patients with acute moderate peritonitis as complication of various diseases (acute appendicitis, perforated gastric or duodenal ulcer, acute intestinal obstruction, acute destructive cholecystitis). Before surgical operation and in the early postoperative period we evaluated the severity of endogenous intoxication by the level of hydrophilic and hydrophobic toxic products. The content of molecular products of lipids peroxidation - oxidative stress, phospholipase activity were determined in the blood plasma. In the study group (n = 28) in the postoperative therapy additionally included remaxol (400 ml intravenous fluids). RESULTS: Research established that the occurrence of endogenous intoxication syndrome in patients with acute peritonitis associated with the activation of oxidative stress and phospholipases, high intensity of which is maintained even after elimination of the source of peritonitis with manifestation on the 1st day after surgery. Remaxol include leads to a significant reduction in the severity of intoxication syndrome in patients with acute peritonitis. Positive effect of the drug on the correction of endogenous intoxication is largely determined by its ability to significantly reduce oxidative stress and the activity of phospholipases, as the most important membrane destabilizing agents. The greatest detoxication effect of the drug is recorded when it is applied already at the preoperative stage of patients when its ability to reduce the activity of trigger agents of catabolic processes implemented to the greatest extent. CONCLUSION: In acute moderate peritonitis, remaxol use before surgery or in the early postoperative period in complex therapy leads to a significant correction of factors contributing to the development and preservation of the intensification of catabolic processes - one of the sources of endogenous intoxication.


Assuntos
Estresse Oxidativo/efeitos dos fármacos , Peritonite/tratamento farmacológico , Substâncias Protetoras/uso terapêutico , Succinatos/uso terapêutico , Doença Aguda , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/fisiologia , Metabolismo/efeitos dos fármacos , Metabolismo/fisiologia , Estresse Oxidativo/fisiologia , Peritonite/etiologia , Peritonite/metabolismo , Peritonite/cirurgia , Substâncias Protetoras/farmacologia , Succinatos/farmacologia
9.
Braz J Med Biol Res ; 52(7): e8429, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31314852

RESUMO

The present study aimed to analyze age-related changes to motor coordination, balance, spinal cord oxidative biomarkers in 3-, 6-, 18-, 24-, and 30-month-old rats. The effects of low-intensity exercise on these parameters were also analyzed in 6-, 18-, and 24-month-old rats. Body weight, blood glucose, total cholesterol, and high-density lipoprotein (HDL) cholesterol were assessed for all rats. The soleus muscle weight/body weight ratio was used to estimate skeletal muscle mass loss. Body weight increased until 24 months; only 30-month-old rats exhibited decreased blood glucose and increased total cholesterol and HDL cholesterol. The soleus muscle weight/body weight ratio increased until 18 months, followed by a small decrease in old rats. Exercise did not change any of these parameters. Stride length and step length increased from adult to middle age, but decreased at old age. Stride width increased while the sciatic functional index decreased in old rats. Performance in the balance beam test declined with age. While gait did not change, balance improved after exercise. Aging increased superoxide anion generation, hydrogen peroxide levels, total antioxidant capacity, and superoxide dismutase activity while total thiol decreased and lipid hydroperoxides did not change. Exercise did not significantly change this scenario. Thus, aging increased oxidative stress in the spinal cord, which may be associated with age-induced changes in gait and balance. Regular low-intensity exercise is a good alternative for improving age-induced changes in balance, while beneficial effects on gait and spinal cord oxidative biomarkers cannot be ruled out because of the small number of rats investigated (n=5 or 6/group).


Assuntos
Fatores Etários , Biomarcadores/sangue , Marcha/fisiologia , Estresse Oxidativo/fisiologia , Condicionamento Físico Animal/fisiologia , Equilíbrio Postural/fisiologia , Medula Espinal/fisiologia , Animais , Biomarcadores/metabolismo , Glicemia/análise , Peso Corporal/fisiologia , Colesterol/sangue , Lipoproteínas HDL/sangue , Masculino , Ratos , Ratos Wistar , Medula Espinal/metabolismo
10.
Life Sci ; 232: 116619, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31265855

RESUMO

AIMS: Clinical treatment strategies for patients with myocardial ischemia typically include coronary artery recanalization to restore myocardial blood supply. However, myocardial reperfusion insult often induces oxidative stress and inflammation, which further leads to apoptosis and necrosis of myocardial cells. Increasing evidence suggests that microRNAs (miRNAs) participate in the pathological and physiological processes associated with myocardial ischemia reperfusion. MAIN METHODS: In this study, we established a myocardial H/R H9C2 cell model and a mouse I/R model to detect molecules implicated in myocardial I/R regulation and to determine the underlying signal transduction pathways. KEY FINDINGS: Herein, we showed that the expression of miR-374a-5p decreased in a myocardial cell model (H9C2 cells) of hypoxia/reoxygenation (H/R) and mouse model of ischemia/reperfusion (I/R). Alternatively, overexpression of miR-374a-5p was found to ameliorate myocardial cell damage within both in vivo and in vitro models of ischemia. Further, mitogen-activated protein kinase 6 (MAPK6) was identified as a direct target of miR-374a-5p. Thus, by targeting MAPK6, miR-374a-5p was found to negatively regulate MAPK6 expression. However, up-regulation of MAPK6 functioned to inhibit the previously observed protective effect of miR-374a-5p in the H9C2 H/R model. SIGNIFICANCE: Taken together, our study suggests that miR-374a-5p may have protective effects against cardiac I/R injury in vivo, and H/R injury in vitro, thereby providing novel insights into the molecular mechanisms associated with ischemia/reperfusion injury and a potential novel therapeutic target.


Assuntos
MicroRNAs/biossíntese , Traumatismo por Reperfusão/metabolismo , Animais , Apoptose/efeitos dos fármacos , Hipóxia Celular/fisiologia , Hipóxia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Proteína Quinase 6 Ativada por Mitógeno/genética , Proteína Quinase 6 Ativada por Mitógeno/metabolismo , Isquemia Miocárdica/genética , Isquemia Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/fisiologia , Ratos , Traumatismo por Reperfusão/genética , Transdução de Sinais
11.
Pestic Biochem Physiol ; 157: 138-142, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153461

RESUMO

The evidence shows that organophosphate compounds (OPCs), as toxic agents that stimulate the cholinergic system, can increase the incidence of metabolic disorders such as dyslipidemia. In the present study, we focused on the role of tumor necrosis factor alpha (TNF-α) and serum leptin and ghrelin in Diazinon (DZN)-induced dyslipidemia. The rats were randomly divided into five groups comprising eight animals, and all were treated via oral gavage for 28 consecutive days as follows: group one received only corn oil daily, while groups two through five received different doses of DZN dissolved in corn oil equal to 1/40, 1/20, 1/10 and 1/5 of the LD50 daily, respectively. The alteration of the serum lipid profile, such as triglycerides, high-density lipoprotein (HDL) and very-low-density lipoprotein (VLDL), was confirmed the occurrence of dyslipidemia in the range of doses 1/20-1/5 LD50 of DZN. Although no changes were found in the serum leptin levels, a significant increase was observed in the size of adipocytes, as well as in the TNF-α and ghrelin serum levels, and in the accumulation of epididymal fat, especially at a dose of 1/5 LD50 of DZN. It seems that interactions among the inflammatory reaction, cholinergic pathways and ghrelin secretion may be effective causes of DZN-induced dyslipidemia.


Assuntos
Diazinon/farmacologia , Dislipidemias/sangue , Dislipidemias/induzido quimicamente , Grelina/sangue , Fator de Necrose Tumoral alfa/sangue , Animais , Antioxidantes , Butirilcolinesterase/sangue , Leptina/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/fisiologia , Masculino , Compostos Organofosforados/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos
12.
Acta Cir Bras ; 34(5): e201900502, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166463

RESUMO

PURPOSE: To investigate inhibitory effect of Astragalus polysaccharide (APS) on osteoporosis in ovariectomized rats by regulating FoxO3a/Wnt2 signaling pathway. METHODS: Postmenopausal osteoporosis (PMOP) animal model was developed by excising the bilateral ovaries of rats. The model rats were administered with APS (200 mg/kg, 400 mg/kg, 800 mg/kg) by intragastric administration once daily for 12 weeks. Bone density, bone metabolism index and oxidative stress index were measured in all groups. Furthermore, the regulation of APS of FoxO3a / Wnt2 signaling pathway was observed. RESULTS: APS has an estrogen-like effect, which can increase bone mass, lower serum ALP and BGP values, increase blood calcium content, and increase bone density of the femur and vertebrae in rats. At the same time, APS can increase the bone mineral content of the femur, increase the maximum stress, maximum load and elastic modulus of the ovariectomized rats, improve oxidative stress in rats by increasing the gene expression of ß-catenin and Wnt2 mRNA and inhibiting the gene expression of FoxO3a mRNA. CONCLUSION: Astragalus polysaccharide can effectively alleviate oxidative stress-mediated osteoporosis in ovariectomized rats, which may be related to its regulation of FoxO3a/Wnt2/ß-catenin pathway.


Assuntos
Astrágalo (Planta)/química , Proteína Forkhead Box O3/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Polissacarídeos/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Densidade Óssea/efeitos dos fármacos , Feminino , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Proteína Forkhead Box O3/análise , Expressão Gênica/efeitos dos fármacos , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/análise , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/efeitos dos fármacos , Osteoporose/metabolismo , Ovariectomia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Distribuição Aleatória , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Reprodutibilidade dos Testes , Resultado do Tratamento , Via de Sinalização Wnt/fisiologia , Proteína Wnt2/análise , Proteína Wnt2/efeitos dos fármacos , beta Catenina/análise , beta Catenina/efeitos dos fármacos
13.
Biochemistry (Mosc) ; 84(Suppl 1): S206-S224, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31213203

RESUMO

Reactive carbonyl compounds (RCC) are a group of compounds with clearly pronounced electrophilic properties that facilitate their spontaneous reactions with numerous nucleophilic reaction sites in proteins, lipids, and nucleic acids. The biological functions of RCC are determined by their concentration and governed by the hormesis (biphasic reaction) principle. At low concentrations, RCC act as signaling molecules activating defense systems against xenobiotics and oxidizers, and at high concentrations, they exhibit the cytotoxic effect. RCC participate in the formation of cell adaptive response via intracellular signaling pathways involving regulation of gene expression and cytoplasmic mechanisms related to the structure-functional rearrangements of proteins. Special attention in this review is given to the functioning of electrophiles as mediators of cell general adaption syndrome manifested as the biphasic response. The hypothesis is proposed that electrophilic signaling can be a proto-signaling system.


Assuntos
Aldeídos/metabolismo , Radicais Livres/metabolismo , Cetonas/metabolismo , Mutagênese/fisiologia , Estresse Oxidativo/fisiologia , Transdução de Sinais/fisiologia , Animais , Humanos , Oxirredução , Processamento de Proteína Pós-Traducional
14.
J Basic Microbiol ; 59(8): 834-845, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31210376

RESUMO

A bacterium's ability to thrive in the presence of multiple environmental stressors simultaneously determines its resilience. We showed that activation of the SigB-controlled general stress response by mild environmental or energy stress provided significant cross-protection to subsequent lethal oxidative, disulfide and nitrosative stress in Bacillus subtilis. SigB activation is mediated via the stressosome and RsbP, the main conduits of environmental and energy stress, respectively. Cells exposed to mild environmental stress while lacking the major stressosome components RsbT or RsbRA were highly sensitive to subsequent oxidative stress, whereas rsbRB, rsbRC, rsbRD, and ytvA null mutants showed a spectrum of sensitivity, confirming their redundant roles and suggesting they could modulate the signals generated by environmental or oxidative stress. By contrast, cells encountering stationary phase stress required RsbP but not RsbT to survive subsequent oxidative stress. Interestingly, optimum cross-protection against nitrosative stress caused by sodium nitropruside required SigB but not the known regulators, RsbT and RsbP, suggesting an additional and as yet uncharacterized route of SigB activation independent of the known regulators. Together, these results provide mechanistic information on how B. subtilis promotes enhanced resistance against lethal oxidative stress during mild environmental and energy stress conditions.


Assuntos
Bacillus subtilis/fisiologia , Proteínas de Bactérias/metabolismo , Estresse Oxidativo/fisiologia , Fosfoproteínas Fosfatases/metabolismo , Fator sigma/metabolismo , Transdução de Sinais , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Deleção de Genes , Viabilidade Microbiana , Estresse Nitrosativo/fisiologia , Fosfoproteínas Fosfatases/genética , Fosfoproteínas/genética , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Fator sigma/genética , Transdução de Sinais/genética
15.
Environ Sci Pollut Res Int ; 26(23): 24010-24019, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31222653

RESUMO

Actinomycetes are a group of the Gram-positive bacteria famous for their antimicrobial, anticancer, anti-parasitic, and anti-inflammatory activities. This study aimed to investigate the efficacy of two bacterial extracts derived from two soil actinomycete strains (S19 and G30) against carbon tetrachloride (CCl4)-induced nephrotoxicity in experimental rats. Sixty-four male rats were assigned to four groups of 16 rats in each group. The 1st group was kept as a normal (control) group and given corn oil combined with the used production medium, while the 2nd group received only CCl4 (CCl4 group). On the other hand, the 3rd group (CCl4+S19) was administered CCl4 and the extract of the actinomycete strain S19 and the 4th group (CCl4+G30) received CCl4 and the extract of the actinomycete strain G30, both treatments for 8 weeks. The results revealed that the two actinomycete extracts S19 and G30 could significantly (p < 0.01) lower the elevated levels of serum creatinine, urea, and uric acid caused by the CCl4 administration. Additionally, the two actinomycete extracts improved the decreased serum total protein. Interestingly, treatment of the CCl4-intoxicated rats with S19 and G30 extracts remarkably reversed the lowered renal glutathione (GSH), glutathione peroxidase (GSH-Px), peroxidase (Px) and superoxide dismutase (SOD) activities, and the elevated lipid peroxidation (LPO) levels. The histopathological examination of the treated kidney revealed that the two actinomycete extracts improved rats against CCl4-induced kidney lesions. The present results suggested that the protective effect of the two actinomycete extracts may rely on its effect on reducing the oxidative stress and improving the antioxidant defense system.


Assuntos
Actinobacteria/metabolismo , Fatores Biológicos/metabolismo , Tetracloreto de Carbono/toxicidade , Estresse Oxidativo/fisiologia , Animais , Antioxidantes/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Rim/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
16.
Environ Sci Pollut Res Int ; 26(23): 23967-23980, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31222655

RESUMO

Cadmium (Cd) is a heavy metal that poses a huge potential threat to human and animal health. Therefore, it is necessary to study its damage mechanism. In the present study, we have examined the protective effects of Ganoderma lucidum triterpenoids on oxidative stress and apoptosis in the spleen of chickens induced by Cd. One hundred and twenty healthy Hailan white chickens (7-day-old) were randomly divided into the following four groups: control group, Cd group, triterpenoid group, and Cd-triterpenoid group. The chickens were euthanized on the 20th, 40th, and 60th days, and the spleens were removed. Cd and malondialdehyde (MDA) content, antioxidant enzyme (superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)) activities, and inflammatory factor (tumor necrosis factor alpha (TNF-α) and interleukin (IL-1ß and IL-6)) and apoptotic factor (caspase-3, BAX, and Bcl-2) expressions were detected. The results showed that Ganoderma lucidum triterpenoids could reduce the content of Cd and MDA; increase the antioxidant enzyme activities (SOD and GSH-Px); decrease the expression of inflammatory factors (TNF-α) and interleukin (IL-1ß and IL-6); increase the expression of apoptotic factor (Bcl-2); and decrease the expression of apoptotic factors (caspase-3 and Bax). It showed that the triterpenoids of Ganoderma lucidum had significant protective effects on oxidative stress and apoptosis of chicken spleen, which provided a theoretical basis for further prevention and treatment of cadmium poisoning.


Assuntos
Antioxidantes/metabolismo , Cádmio/toxicidade , Substâncias Perigosas/toxicidade , Reishi , Terpenos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cádmio/metabolismo , Caspase 3 , Galinhas/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/fisiologia , Baço/metabolismo , Superóxido Dismutase/metabolismo
17.
Sci Total Environ ; 685: 332-344, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31176220

RESUMO

The present study assessed the spatial and temporal variations on metal bioaccumulation and biochemical biomarker responses in oysters Crassostrea gasar transplanted to two different sites (S1 and S2) at the Laguna Estuarine System (LES), southern Brazil, over a 45-days period. A multi-biomarker approach was used, including the evaluation of lipid peroxidation (MDA) levels, and antioxidant defense enzymes (CAT, GPx, GR and G6PDH) and phase II biotransformation enzyme (GST) in the gills and digestive gland of oysters in combination with the quantification of Al, Cd, Cu, Pb, Fe, Ni and Zn in both tissues. The exposed oysters bioaccumulated metals, especially Al, Cd and Zn in gills and digestive gland, with most prominent biomarker responses in the gills. Results showed that GPx, GR and G6PDH enzymes offered an increased and coordinated response possibly against metal (Zn, Ni, Cd and Cu) contamination in gills. GST was inversely correlated to Cd levels, being its activity significantly lowered over the 45-d exposure periods at S2. On contrary, in digestive gland GST was slightly positively correlated to Cd, revealing a compensatory mechanism between tissues to protect oysters' cells against oxidative damages, since MDA levels also decreased. CAT also appeared to be involved in the cellular protection against oxidative stress, being increased in gills. However, CAT was negatively correlated to Al levels, which might suggest a possible inhibitory effect of this metal in the gills of C. gasar. Differences between tissues were evident by the Integrative Biomarker Responses version 2 (IBRv2) indexes, which showed different pattern between tissues when studying the sites and exposure periods separately. This study provided evidence for the effectiveness of using a multi-biomarker approach in oyster C. gasar to monitor estuarine metal pollution.


Assuntos
Crassostrea/fisiologia , Monitoramento Ambiental , Metais/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Brasil , Estuários , Brânquias/metabolismo , Inativação Metabólica , Peroxidação de Lipídeos/efeitos dos fármacos , Metais/toxicidade , Oxirredução , Estresse Oxidativo/fisiologia , Poluentes Químicos da Água/toxicidade
18.
Life Sci ; 232: 116526, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170418

RESUMO

Tumors and heart disease are two of the leading causes of human death. With the development of anti-cancer therapy, the survival rate of cancer patients has been significantly improved. But at the same time, the incidence of cardiovascular adverse events caused by cancer treatment has also been considerably increased, such as arrhythmia, left ventricular (LV) systolic and diastolic dysfunction, and even heart failure (HF), etc., which seriously affects the quality of life of cancer patients. More importantly, the occurrence of adverse events may lead to the adjustment or the cessation of anti-cancer treatment, which affects the survival rate of patients. Understanding the mechanism of cardiotoxicity (CTX) induced by antineoplastic drugs is the basis of adequate protection of the heart without impairing the efficacy of antineoplastic therapy. Based on current research, a large amount of evidence has shown that oxidative stress (OS) plays an essential role in CTX induced by antineoplastic drugs and participates in its toxic reaction directly and indirectly. Here, we will review the mechanism of action of OS in cardiac toxicity of antineoplastic drugs, to provide new ideas for researchers, and provide further guidance for clinical prevention and treatment of cardiac toxicity of anti-tumor drugs in the future.


Assuntos
Antineoplásicos/metabolismo , Cardiotoxicidade/prevenção & controle , Estresse Oxidativo/fisiologia , Antineoplásicos/efeitos adversos , Arritmias Cardíacas/complicações , Arritmias Cardíacas/fisiopatologia , Cardiotoxicidade/metabolismo , Coração/fisiopatologia , Cardiopatias/tratamento farmacológico , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/fisiopatologia , Humanos , Neoplasias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Qualidade de Vida
19.
Life Sci ; 232: 116579, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31252001

RESUMO

AIMS: We sought to evaluate the effects of maternal protein restriction (LP) on oxidative balance and transcription factors for mitochondrial biogenesis in the hearts of young female rats of both the first (F1) and second (F2) generation. MAIN METHODS: We evaluated oxidative stress biomarkers (lipid peroxidation and protein oxidation), enzymatic antioxidant defense (activity of superoxide dismutase-SOD, catalase, and glutathione-S-transferase-GST), nonenzymatic antioxidant defense (reduced glutathione-GSH and sulfhydryl groups) and gene expression of AMPK, PGC-1α and TFAM. KEY FINDINGS: Interestingly, lipid peroxidation was decreased (49%, p < 0.001) in the LP-F1 group and 59% (p < 0.001) in LP-F2. In enzymatic defense, we observed increases in SOD activity in the LP-F1 group (79%, p = 0.036) and in CAT activity (approximately 40%, p = 0.041). GSH was increased in F2 in both groups (LP 546%, p < 0.0001 and in NP 491.7%, p < 0.0001). With respect to mitochondrial biogenesis gene transcription, we observed a decrease in AMPK (60%, p < 0. 0001) and an increase in PGC-1α (340%, p < 0.001) in LP compared to NP in the F1 generation. TFAM was decreased in LP-F2L compared to NP-F2L (42%, p = 0.0069) and increased in LP-F2 compared to LP-F1 (160%, p = 0.0037). SIGNIFICANCE: Our study contributes to knowledge of inheritance, showing that despite the potential mitochondrial 'inheritance' of cardiovascular damage caused by maternal malnutrition, that damage is not cross-generational and can be eliminated with proper nutrition in the F1 generation.


Assuntos
Miocárdio/metabolismo , Estresse Oxidativo/fisiologia , Desnutrição Proteico-Calórica/metabolismo , Animais , Antioxidantes/farmacologia , Feminino , Glutationa/metabolismo , Coração/efeitos dos fármacos , Coração/fisiologia , Hereditariedade/genética , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Biogênese de Organelas , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ratos , Superóxido Dismutase/metabolismo , Fatores de Transcrição/metabolismo
20.
Life Sci ; 232: 116607, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31254582

RESUMO

AIMS: Poisoning with aluminium phosphide (AlP) commonly has a high rate of mortality and morbidities. Phosphine gas is the main cause of AlP poisoning that has deleterious effect on multi-organs especially heart, kidney, and liver. Furthermore, several studies reported that resveratrol has cytoprotective effects through its pleiotropic property. The purpose of this study was to estimate the dose-dependent role of resveratrol on phosphine induced acute hepatic toxicity in rat model. MAIN METHODS: The rats have been exposed to LD50 of AlP (12 mg/kg) by gavage, and resveratrol doses (20, 40, and 80 mg/kg) were injected 30 min after intoxication. After 24 h, the serum and liver tissue were collected for present study. KEY FINDINGS: The results indicated that phosphine causes an alteration in oxidative stress markers including elevation of ROS, and GSH level, MPO activity, reduction in SOD, catalase and G6PD activity as well as reduction in SOD1 and catalase expression. Furthermore, phosphine significantly induced phosphorylation of IkappaB, NF-kappaB and up-regulation of TNF-α, IL-1ß, IL-6, and ICAM-1 expression. Also, phosphine induces markedly reduced hepatocytes lives cell and elevated apoptosis and necrosis. Co-treatment of resveratrol in a dose-dependent manner reversed aforementioned alterations. All in all, histological analysis indicated a deleterious effect of phosphine on the liver, which is mitigated by resveratrol administration. SIGNIFICANCE: The results of the present study suggest targeting ROS/NF-kappaB signalling pathway by resveratrol may have a significant effect on the improvement of hepatic injury induced by phosphine. It also may be a possible candidate for the treatment of phosphine-poisoning.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/fisiologia , Fosfinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , NF-kappa B/isolamento & purificação , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Ratos , Ratos Wistar , Resveratrol/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
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