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1.
Toxicol Ind Health ; 39(11): 638-650, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37705340

RESUMO

Manganese (Mn) is an abundant element used for commercial purposes and is essential for the proper function of biological systems. Chronic exposure to high Mn concentrations causes Manganism, a Parkinson's-like neurological disorder. The pathophysiological mechanism of Manganism remains unknown; however, it involves mitochondrial dysfunction and oxidative stress. This study assessed the neuroprotective effect of probucol, a hypolipidemic agent with anti-inflammatory and antioxidant properties, on cell viability and oxidative stress in slices of the cerebral cortex and striatum from adult male Wistar rats. Brain structure slices were kept separately and incubated with manganese chloride (MnCl2) and probucol to evaluate the cell viability and oxidative parameters. Probucol prevented Mn toxicity in the cerebral cortex and striatum, as evidenced by the preservation of cell viability observed with probucol (10 and 30 µM) pre-treatment, as well as the prevention of mitochondrial complex I inhibition in the striatum (30 µM). These findings support the protective antioxidant action of probucol, attributed to its ability to prevent cell death and mitigate Mn-induced mitochondrial dysfunction.


Assuntos
Antioxidantes , Manganês , Ratos , Animais , Masculino , Manganês/toxicidade , Ratos Wistar , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Probucol/farmacologia , Probucol/metabolismo , Neuroproteção , Estresse Oxidativo , Encéfalo
2.
BMC Cancer ; 21(1): 205, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33639868

RESUMO

BACKGROUND: Oral cancer (OC) is usually diagnosed at advanced clinical stages due to its asymptomatic nature and absence of pathognomonic signs in its early development phase. Delayed diagnosis is one of the major causes of OC treatment failure and poor prognosis. Development of alternative diagnostic approaches are imperative for improving early detection and therapeutic success rates. Salivary cytokines (SC) have been studied as potential diagnostic biomarkers for OC and may represent a potential tool for improvement of its early detection. METHODS: In this systematic review and meta-analysis we identified SC studied as OC biomarkers by systematically reviewing the PubMed and Cochrane Library databases using the terms: "oral cancer", "cytokine", and "saliva", and also combined with "interleukin" or "interferon". Only case-control studies that measured SC by ELISA from treatment naïve patients were included in the qualitative review. For the meta-analysis were included all comparable studies that provided enough data (sample size, mean and standard deviation or standard error of the mean) for SC levels in OC patients, non-cancer controls and patients with oral potentially malignant disorders (OPMD), including leukoplakia. Comparisons with patients with oral lichen planus (OLP) and gingivitis were included in the qualitative analysis. RESULTS: A total of 28 articles (from 2004 to 2018) were included in the systematic review, describing 10 different SC, being IL-8 and IL-6 the most studied ones. SC levels were consistently higher among OC patients when compared to healthy controls and to patients with OPMD, OLP and gingivitis. Meta-analysis including 23 eligible studies showed that IL-8, IL-6, TNF-α, IL-1ß and IL-10 salivary levels were significantly higher in OC patients compared to controls; and that IL-8, IL-6, TNF-α and IL-1ß salivary levels were also higher in OC patients compared to individuals with OPMD. When compared to healthy controls, OPMD patients showed significantly higher IL-6 and TNF-α salivary levels. CONCLUSIONS: Our analyses showed that the salivary levels of some cytokines are consistently different among OC, OPMD and healthy patients, indicating that these SC may represent potential diagnostic biomarkers for OC and OPMD. Despite of that, SC levels were highly variable among studies, suggesting that further technical improvement and standardization for SC measurement by ELISA is needed in order to successfully translate these biomarkers to the clinical practice.


Assuntos
Biomarcadores Tumorais/análise , Citocinas/análise , Detecção Precoce de Câncer/métodos , Neoplasias Bucais/química , Saliva/química , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática , Gengivite/diagnóstico , Humanos , Leucoplasia Oral/diagnóstico , Líquen Plano Bucal/diagnóstico , Neoplasias Bucais/diagnóstico , Lesões Pré-Cancerosas/diagnóstico
3.
Cell Biol Toxicol ; 35(1): 49-58, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29961152

RESUMO

Developmental endochondral ossification requires constant blood supply, which is provided by the embryonic vascular network. High levels of homocysteine (Hcy) have vasculotoxic properties, but it remains unclear how Hcy disrupts blood vessel formation in endochondral ossification. Thus, we investigated the toxicity of Hcy on contents of vasculogenic factors (VEGF, VCAM-1, NOS3) and osteocalcin, using developing limbs as model. Chicken embryos were submitted to treatment with 20 µmol D-L Hcy at 12H&H and the analyses occur at 29H&H and 36H&H. We did not identify differences in the area of limb ossification in Hcy-treated (7.5 × 105 µm2 ± 3.9 × 104) and untreated embryos (7.6 × 105 µm2 ± 3.3 × 104) at 36H&H. In Hcy-treated embryos, we observed a significantly decrease of 46.8% at 29H&H and 26.0% at 36H&H in the number of VEGF-reactive cells. Also, treated embryos showed decrease of 98.7% in VCAM-1-reactive cells at 29H&H and 34.6% at 36H&H. The number of NOS3-reactive cells was reduced 54.0% at 29H&H and 91.5% at 36H&H, in the limbs of Hcy-treated embryos. Finally, in Hcy-treated embryos at 36H&H, we observed a reduction of 58.86% in the number of osteocalcin-reactive cells. Here, we demonstrated for the first time that the toxicity of Hcy is associated with a reduction in the contents of proteins involved in blood vessel formation and bone mineralization, which interferes with endochondral ossification of the limb during embryonic development. Graphical abstract.


Assuntos
Indutores da Angiogênese/metabolismo , Homocisteína/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Calcificação Fisiológica/efeitos dos fármacos , Embrião de Galinha , Neovascularização Fisiológica/efeitos dos fármacos , Osteocalcina/metabolismo
4.
Regul Toxicol Pharmacol ; 104: 98-107, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30878574

RESUMO

INTRODUCTION: Manganese (Mn) is an essential element required for several biological systems. However, it is toxic in excessive accumulation. The toxic effects following Mn overexposure is well known in the CNS but other studies evaluating other target tissues remain scarce. OBJECTIVE: This study aimed to investigate sex-related differences in oxidative stress, metabolic parameters and Mn deposition in peripheral organs of Wistar rats exposed to subacute model of intoxication. METHODS: Male and female adult Wistar rats received 6 or 15 mg/kg of MnCl2, intraperitoneally, 5 days a week, for 4 consecutive weeks to mimic subacute intoxication. Control group received sterile saline 0,9% following the same protocol. After this period, the metal accumulation, oxidative stress, mitochondrial activity and histological parameters in cardiac muscle, kidney, lungs and liver were analysed. RESULTS: Increased Mn concentrations were found in all organs, especially kidneys. The cardiac muscle analysis revealed increased lipid peroxidation and decreasing of GSH levels in both doses of Mn in male and female rats. The increase of lipid peroxidation in liver was more evident in the male group, and there was a significant decrease of antioxidant capacity in males' kidney. Nevertheless, there was an increase of mitochondrial complex I activity in kidney of females and increase of mitochondrial complex II activity in male group. Histological analysis revealed morphological changes in hepatic and pulmonary tissue. CONCLUSION: Taken together, our results showed that subacute Mn exposure lead to significant metabolic, biochemical alterations especially in kidney and liver. Nevertheless, despite Mn deposition was virtually the same in the peripheral organs of male and female rats, it promotes different toxic effects between sexes.


Assuntos
Coração/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Manganês/farmacocinética , Manganês/toxicidade , Caracteres Sexuais , Animais , Relação Dose-Resposta a Droga , Feminino , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Masculino , Manganês/administração & dosagem , Manganês/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
5.
Brain Behav Immun ; 61: 31-35, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27477921

RESUMO

Exercise improves mental health and synaptic function in the aged brain. However, the molecular mechanisms involved in exercise-induced healthy brain aging are not well understood. Evidence supports the role of neurogenesis and neurotrophins in exercise-induced neuroplasticity. The gene silencing transcription factor neuronal RE1-silencing transcription factor (REST)/neuron-restrictive silencer factor (NRSF) and an anti-inflammatory role of exercise are also candidate mechanisms. We evaluate the effect of 8weeks of physical activity on running wheels (RW) on motor and depressive-like behavior and hippocampal gene expression of brain-derived neurotrophic factor (BDNF), REST, and interleukins IL-1ß and IL-10 of adult and aged C57BL/6 mice. The aged animals exhibited impaired motor function and a depressive-like behavior: decreased mobility in the RW and open field and severe immobility in the tail suspension test. The gene expression of REST, IL-1ß, and IL-10 was increased in the hippocampus of aged mice. Physical activity was anxiolytic and antidepressant and improved motor behavior in aged animals. Physical activity also boosted BDNF and REST expression and decreased IL-1ß and IL-10 expression in the hippocampus of aged animals. These results support the beneficial role of REST in the aged brain, which can be further enhanced by regular physical activity.


Assuntos
Envelhecimento/metabolismo , Comportamento Animal/fisiologia , Depressão/metabolismo , Hipocampo/metabolismo , Inflamação/metabolismo , Atividade Motora/fisiologia , Condicionamento Físico Animal/fisiologia , Afeto/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Interleucina-10/sangue , Interleucina-1beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo
6.
Neurochem Res ; 41(1-2): 64-72, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26323504

RESUMO

INTRODUCTION: Exercise improves the motor symptoms of patients with Parkinson disease in a palliative manner. Existing evidence demonstrates that exercise induces neuroprotection based on the neurotrophic properties. We investigated the effect of exercise on mitochondrial physiology and oxidative stress in an animal model of hemiparkinsonism. METHODS: C57BL/6 mice completed a 6-week exercise program on a treadmill. We injected 6-hydroxydopamine (6-OHDA; 4 µg/2 µl) into the midstriatum. The animals progressively developed bradykinesia and R(-)-apomorphine-induced rotations that were attenuated by exercise. Transcriptional activation of protective genes is mediated by the antioxidant response element (ARE). Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) binds to ARE. We investigated the Nrf2-ARE pathway in the striatum of animals. RESULTS: Exercise protected 6-OHDA-induced loss of tyrosine hydroxylase immunolabeling and activated the Nrf2-ARE pathway in the nigrostriatal pathway. Exercise stimulated mitochondrial biogenesis in the striatum of animals that was more resistant to oxidant 6-OHDA and nitric oxide donor (±)-S-nitroso-N-acetylpenicillamine. CONCLUSIONS: In mice, exercise activated Nrf2-ARE signaling in the nigrostriatal pathway that was protective against the development of hemiparkinsonism.


Assuntos
Fator 2 Relacionado a NF-E2/metabolismo , Oxidopamina/toxicidade , Transtornos Parkinsonianos/prevenção & controle , Condicionamento Físico Animal , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transtornos Parkinsonianos/etiologia , Transtornos Parkinsonianos/metabolismo
7.
Neurochem Res ; 41(4): 880-91, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26586405

RESUMO

Mitochondrial respiratory chain complexes enzymatic (MRCCE) activities were successfully evaluated in frozen brain samples. Epilepsy surgery offers an ethical opportunity to study human brain tissue surgically removed to treat drug resistant epilepsies. Epilepsy surgeries are done with hemodynamic and laboratory parameters to maintain physiology, but there are no studies analyzing the association among these parameters and MRCCE activities in the human brain tissue. We determined the intra-operative parameters independently associated with MRCCE activities in middle temporal neocortex (Cx), amygdala (AMY) and head of hippocampus (HIP) samples of patients (n = 23) who underwent temporal lobectomy using multiple linear regressions. MRCCE activities in Cx, AMY and HIP are differentially associated to trans-operative mean arterial blood pressure, O2 saturation, hemoglobin, and anesthesia duration to time of tissue sampling. The time-course between the last seizure occurrence and tissue sampling as well as the sample storage to biochemical assessments were also associated with enzyme activities. Linear regression models including these variables explain 13-17 % of MRCCE activities and show a moderate to strong effect (r = 0.37-0.82). Intraoperative hemodynamic and laboratory parameters as well as the time from last seizure to tissue sampling and storage time are associated with MRCCE activities in human samples from the Cx, AMYG and HIP. Careful control of these parameters is required to minimize confounding biases in studies using human brain samples collected from elective neurosurgery.


Assuntos
Encéfalo/enzimologia , Complexo II de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Epilepsia/enzimologia , Adulto , Lobectomia Temporal Anterior , Encéfalo/patologia , Encéfalo/cirurgia , Epilepsia/patologia , Epilepsia/cirurgia , Feminino , Congelamento , Humanos , Masculino , Manejo de Espécimes/métodos , Succinato Desidrogenase/metabolismo
8.
J Sports Sci ; 32(1): 22-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24117160

RESUMO

The purpose of the present investigation was to identify muscle damage, inflammatory response and oxidative stress blood markers in athletes undertaking the ultra-endurance MultiSport Brazil race. Eleven well-trained male athletes (34.3 ± 3.1 years, 74.0 ± 7.6 kg; 172.2 ± 5.1 cm) participated in the study and performed the race, which consisted of about 90 km of alternating off-road running, mountain biking and kayaking. Twelve hours before and up to 15 minutes after the race a 10 mL blood sample was drawn in order to measure the following parameters: lactate dehydrogenase and creatine kinase activities, lipid peroxidation, catalase activity, protein carbonylation, respiratory chain complexes I, II and IV activities, oxygen consumption and neopterin concentrations. After the race, plasma lactate dehydrogenase and creatine kinase activities were significantly increased. Erythrocyte TBA-RS levels and plasma protein carbonylation were markedly augmented in post-race samples. Additionally, mitochondrial complex II activity and oxygen consumption in post-race platelet-rich plasma were also increased. These altered biochemical parameters were accompanied by increased plasma neopterin levels. The ultra-endurance event provoked systemic inflammation (increased neopterin) accompanied by marked oxidative stress, likely by increasing oxidative metabolism (increased oxidative mitochondrial function). This might be advantageous during prolonged exercise, mainly for efficient substrate oxidation at the mitochondrial level, even when tissue damage is induced.


Assuntos
Biomarcadores/sangue , Plaquetas/metabolismo , Neopterina/sangue , Estresse Oxidativo/fisiologia , Resistência Física/fisiologia , Ciclismo/fisiologia , Catalase/sangue , Comportamento Competitivo/fisiologia , Eritrócitos/metabolismo , Humanos , Peroxidação de Lipídeos , Masculino , Mitocôndrias/metabolismo , Músculo Esquelético/enzimologia , Músculo Esquelético/lesões , Carbonilação Proteica , Corrida/fisiologia
9.
Br J Pharmacol ; 181(7): 1128-1149, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37721089

RESUMO

BACKGROUND AND PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of paclitaxel, affecting 30-50% of patients. Increased survival and concern with patients' quality of life have encouraged the search for new tools to prevent paclitaxel-induced neuropathy. This study presents the glitazone 4-[(Z)-(2,4-dioxo-1,3-thiazolidin-5-ylidene)methyl]-N-phenylbenzene-sulfonamide (TZD-A1) as a partial agonist of peroxisome proliferator-activated receptor γ (PPARγ), its toxicological profile and effects on paclitaxel-induced CIPN in mice. EXPERIMENTAL APPROACH: Interactions of TZD-A1 with PPARγ were analysed using in silico docking and in vitro reporter gene assays. Pharmacokinetics and toxicity were evaluated using in silico, in vitro and in vivo (C57Bl/6 mice) analyses. Effects of TZD-A1 on CIPN were investigated in paclitaxel-injected mice. Axonal and dorsal root ganglion damage, mitochondrial complex activity and cytokine levels, brain-derived neurotrophic factor (BDNF), nuclear factor erythroid 2-related factor 2 (Nrf2) and PPARγ, were also measured. KEY RESULTS: Docking analysis predicted TZD-A1 interactions with PPARγ compatible with partial agonism, which were corroborated by in vitro reporter gene assays. Good oral bioavailability and safety profile of TZD-A1 were shown in silico, in vitro and in vivo. Paclitaxel-injected mice, concomitantly treated with TZD-A1 by i.p. or oral administration, exhibited decreased mechanical and thermal hypersensitivity, effects apparently mediated by inhibition of neuroinflammation and mitochondrial damage, through increasing Nrf2 and PPARγ levels, and up-regulating BDNF. CONCLUSION AND IMPLICATIONS: TZD-A1, a partial agonist of PPARγ, provided neuroprotection and reduced hypersensitivity induced by paclitaxel. Allied to its safety profile and good bioavailability, TZD-A1 is a promising drug candidate to prevent and treat CIPN in cancer patients.


Assuntos
Paclitaxel , Doenças do Sistema Nervoso Periférico , Humanos , Camundongos , Animais , Paclitaxel/toxicidade , PPAR gama , Fator Neurotrófico Derivado do Encéfalo , Fator 2 Relacionado a NF-E2 , Doenças Neuroinflamatórias , Qualidade de Vida , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/prevenção & controle
10.
Mol Neurobiol ; 60(7): 3724-3740, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36940076

RESUMO

The constant exposure of rural workers to pesticides is a serious public health problem. Mancozeb (MZ) is a pesticide  linked to hormonal, behavioral, genetic, and neurodegenerative effects, mainly related to oxidative stress. Vitamin D is a promising molecule that acts as a protector against brain aging. This study aimed to evaluate the neuroprotective role of vitamin D in adult male and female Wistar rats exposed to MZ. Animals received 40 mg/kg of MZ i.p. and 12.5 µg/kg or 25 µg/kg vitamin D by gavage, twice a week, for 6 weeks. The concentration of manganese had a significant increase in the hippocampus of both sexes and in the striatum of females, unlike zinc, which did not show a significant increase. MZ poisoning led to mitochondrial changes in brain tissues and promoted anxiogenic effects, especially in females. Alterations in antioxidant enzymes, mainly in the catalase activity were observed in intoxicated rats. Taken together, our results showed that exposure to MZ leads to the accumulation of manganese in brain tissues, and the behavior and metabolic/oxidative impairment were different between the sexes. Furthermore, the administration of Vitamin D was effective in preventing the damage caused by the pesticide.


Assuntos
Fungicidas Industriais , Fármacos Neuroprotetores , Feminino , Masculino , Ratos , Animais , Ratos Wistar , Fungicidas Industriais/farmacologia , Manganês/toxicidade , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Vitamina D/farmacologia , Zinco/farmacologia , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Estresse Oxidativo , Etilenos/farmacologia
11.
Biochim Biophys Acta ; 1812(11): 1460-71, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21767639

RESUMO

Large scale clinical trials have demonstrated that an intensive antihyperglycemic treatment in diabetes mellitus (DM) in individuals reduces the incidence of micro- and macrovascular complications, e.g. nephropathy, retinopathy, DM-accelerated atherosclerosis, myocardial infarction, or limb amputations. Here, we investigated the effect of short- and long-term insulin administration on mitochondrial function in peripheral tissues of streptozotocin (STZ)-induced hyperglycemic rats. In addition, the in vitro effect of methylglyoxal (MG), advanced glycation end products (AGEs) and human diabetic plasma on mitochondrial activity was investigated in skeletal muscle and liver mitochondria and in rat skin primary fibroblasts. Hyperglycemic STZ rats showed tissue-specific patterns of energy deficiency, evidenced by reduced activities of complexes I, II and/or IV after 30 days of hyperglycemia in heart, skeletal muscle and liver; moreover, cardiac tissue was found to be the most sensitive to the diabetic condition, since energy metabolism was impaired after 10 days of the hyperglycemia. Insulin-induced tight glycemic control was effective in protecting against the hyperglycemia-induced inhibition of mitochondrial enzyme activities. Furthermore, the long-term hormone replacement (30 days) also increased these activities in kidney from STZ-treated animals, where the hyperglycemic state did not modify the electron transport activity. Results from in vitro experiments indicate that mitochondrial impairment could result from oxidative stress-induced accumulation of MG and/or AGEs. Further investigations demonstrated that human plasma AGE accumulation elicits reduced mitochondrial function in skin fibroblast. These data suggest that persistent hyperglycemia results in tissue-specific patterns of energy deficiency and that early and continuous insulin therapy is necessary to maintain proper mitochondrial metabolism.


Assuntos
Diabetes Mellitus/fisiopatologia , Metabolismo Energético , Produtos Finais de Glicação Avançada/metabolismo , Hiperglicemia/fisiopatologia , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Mitocôndrias/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antibióticos Antineoplásicos/toxicidade , Glicemia/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Transporte de Elétrons , Fibroblastos/citologia , Fibroblastos/metabolismo , Coração/fisiologia , Humanos , Hiperglicemia/induzido quimicamente , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Mitocôndrias/patologia , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Estresse Oxidativo , Consumo de Oxigênio , Aldeído Pirúvico/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Pele/citologia , Pele/metabolismo , Estreptozocina/toxicidade
12.
Neurotox Res ; 40(1): 276-285, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35043377

RESUMO

Manganese (Mn) is an essential metal for many functions in the body. However, in excess, it can be neurotoxic and cause a Parkinson-like syndrome, known as manganism. Here, we aimed to identify a protective effect of probucol, a lipid-lowering agent with anti-inflammatory and antioxidant properties, against Mn-induced toxicity in human neuroblastoma (SH-SY5Y) and glioblastoma (C6) cell lines. The cells were incubated with increasing concentrations of Mn followed by probucol addition 1, 3, 6, and/or 24 h to assess the metal toxic doses and measure the protective effect of probucol against Mn-induced oxidative damage. Longer exposition to Mn showed decreased SH-SY5Y cellular viability in concentrations higher than 100 µM, and probucol was able to prevent this effect. The C6 cells were more sensitive to the Mn deleterious actions, decreasing the cell viability after 6 h of 500 µM Mn exposure. In addition, probucol prevents the complex I and II of the mitochondrial respiratory chain (MRC) inhibition caused by Mn and decreased the intracellular ROS production. Taken together, our results showed that Mn toxicity affects differently both cell lines and probucol has a protective effect against the oxidative imbalance in the central nervous system.


Assuntos
Manganês , Probucol , Encéfalo/metabolismo , Linhagem Celular Tumoral , Humanos , Manganês/metabolismo , Manganês/toxicidade , Estresse Oxidativo , Probucol/metabolismo , Probucol/farmacologia
13.
Med Eng Phys ; 71: 108-113, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31303375

RESUMO

The purpose of this study was to investigate the effect of different doses of photobiomodulation (PBM) on mitochondrial respiratory complexes and oxidative cellular energy metabolic enzymes in the mitochondria of brain, muscle, and C6 glioma cells after different time intervals. C6 cells were irradiated with an AlGaInP laser at 10, 30, and 60 J/cm2 for 20, 60, and 120 s, respectively. After irradiation, the cells were maintained in serum-free Dulbecco's Modified Eagle's medium for 24 h, and biochemical measurements were made subsequently. Mitochondrial suspensions from adult rat skeletal muscles/brains were irradiated with an AlGaInP laser at the abovementioned doses. In one group, the reaction was stopped 5 min after irradiation and in the other 60 min after irradiation. Both the C6 cells that received the doses of 10 and 30 J/cm² showed increased complex I activity; the cells that were irradiated at 30 J/cm2 showed increased hexokinase activity. Five minutes after the introduction of PBM of the muscle mitochondria (at 30 and 60 J/cm2), the activity of complex I increased, while the activity of complex IV increased only at 60 J/cm2. One hour after the laser session, complex II activity increased in the cells treated with 10 and 60 J/cm²; however, complex IV activity showed an increase in all PBM groups. In brain mitochondria, 5 min after irradiation only the activity of complex IV increased in all PBM groups. One hour after the laser session, complex II activity increased at 60 J/cm2, and complex IV activity increased for all PBM groups when compared to controls. PBM could increase the activity of respiratory chain complexes in an apparently dose- and time-dependent manner.


Assuntos
Astrocitoma/patologia , Encéfalo/citologia , Terapia com Luz de Baixa Intensidade , Mitocôndrias/efeitos da radiação , Músculos/citologia , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Transporte de Elétrons/efeitos da radiação , Humanos , Mitocôndrias/metabolismo , Fatores de Tempo
14.
Mol Neurobiol ; 56(3): 1539-1557, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29948953

RESUMO

Chronic metabolic alterations may represent a risk factor for the development of cognitive impairment, dementia, or neurodegenerative diseases. Hyperglycemia and obesity are known to imprint epigenetic markers that compromise the proper expression of cell survival genes. Here, we showed that chronic hyperglycemia (60 days) induced by a single intraperitoneal injection of streptozotocin compromised cognition by reducing hippocampal ERK signaling and by inducing neurotoxicity in rats. The mechanisms appear to be linked to reduced active DNA demethylation and diminished expression of the neuroprotective transcription factor REST. The impact of the relationship between adiposity and DNA hypermethylation on REST expression was also demonstrated in peripheral blood mononuclear cells in obese children with reduced levels of blood ascorbate. The reversible nature of epigenetic modifications and the cognitive impairment reported in obese children, adolescents, and adults suggest that the correction of the anthropometry and the peripheral metabolic alterations would protect brain homeostasis and reduce the risk of developing neurodegenerative diseases.


Assuntos
Transtornos Cognitivos/etiologia , Diabetes Mellitus Experimental/complicações , Hipocampo/metabolismo , Hiperglicemia/complicações , Proteínas Repressoras/metabolismo , Animais , Aprendizagem da Esquiva/fisiologia , Transtornos Cognitivos/genética , Transtornos Cognitivos/metabolismo , Metilação de DNA , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Humanos , Hiperglicemia/genética , Hiperglicemia/metabolismo , Aprendizagem em Labirinto/fisiologia , Ratos , Proteínas Repressoras/genética
15.
J Cell Commun Signal ; 11(3): 233-243, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28160135

RESUMO

1α,25-Dihydroxyvitamin D3 (1,25-D3) is critical for the maintenance of normal male reproduction since reduced fertility is observed in vitamin D-deficient rats. Gamma-glutamyl transpeptidase (GGT) is a membrane-bound enzyme that is localized on Sertoli cells and catalyses the transfer of the gamma-glutamyl residues to an amino acid or peptide acceptor. Sertoli cells are also responsible for providing nutrients, as lactate, to the development of germ cells. The aim of this study was to investigate the effect and the mechanism of action of 1,25-D3 on GGT on Sertoli cell functions from 30-day-old immature rat testis. Results demonstrated that 1,25-D3 stimulates GGT activity at Sertoli cells plasma membrane through a PKA-dependent mechanism of action, which was not dependent of active de novo protein synthesis. The hormone increases glucose uptake, as well as lactate production and release by Sertoli cells without altering the reactive oxygen species (ROS) generation. In addition, 1,25-D3 did not change reduced glutathione (GSH) amount or oxygen consumption, and diminished Sertoli cell death. These findings demonstrate that 1,25-D3 stimulatory effect on GGT activity, glucose uptake, LDH activity and lactate production seem to be an important contribution of Sertoli cells for germ cells nutrition and for a full and active ongoing spermatogenesis.

16.
Epilepsy Res ; 138: 26-31, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29040828

RESUMO

Interictal hypometabolism is commonly measured by 18-fluoro-deoxyglucose Positron Emission Tomography (FDG-PET) in the temporal lobe of patients with mesial temporal lobe epilepsy (MTLE-HS). Left temporal lobe interictal FDG-PET hypometabolism has been associated with verbal memory impairment, while right temporal lobe FDG-PET hypometabolism is associated with nonverbal memory impairment. The biochemical mechanisms involved in these findings remain unknown. In comparison to healthy controls (n=21), surgically treated patients with MTLE-HS (n=32, left side=17) had significant lower scores in the Rey Auditory Verbal Learning Test (RAVLT retention and delayed), Logical Memory II (LMII), Boston Naming test (BNT), Letter Fluency and Category Fluency. We investigated whether enzymatic activities of the mitochondrial enzymes Complex I (C I), Complex II (C II), Complex IV (C IV) and Succinate Dehydrogenase (SDH) from the resected samples of the middle temporal neocortex (mTCx), amygdala (AMY) and hippocampus (HIP) were associated with performance in the RAVLT, LMII, BNT and fluency tests of our patients. After controlling for the side of hippocampus sclerosis, years of education, disease duration, antiepileptic treatment and seizure outcome after surgery, no independent associations were observed between the cognitive test scores and the analyzed mitochondrial enzymatic activities (p>0.37). Results indicate that memory and language impairment observed in MTLE-HS patients are not strongly associated with the levels of mitochondrial CI, CII, SDH and C IV enzymatic activities in the temporal lobe structures ipsilateral to the HS lesion.


Assuntos
Encéfalo/metabolismo , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/patologia , Transtornos da Memória/etiologia , Complexos Multienzimáticos/metabolismo , Adulto , Anticonvulsivantes/uso terapêutico , Encéfalo/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/complicações , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/patologia , Eletroencefalografia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/tratamento farmacológico , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Transtornos da Memória/diagnóstico por imagem , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Estatísticas não Paramétricas
17.
Free Radic Res ; 50(5): 503-13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26983894

RESUMO

The purpose of this work was to investigate the effect of early and long-term low-level laser therapy (LLLT) on oxidative stress and inflammatory biomarkers after acute-traumatic muscle injury in Wistar rats. Animals were randomly divided into the following four groups: control group (CG), muscle injury group (IG), CG + LLLT, and IG + LLLT: laser treatment with doses of 3 and 5 J/cm(2). Muscle traumatic injury was induced by a single-impact blunt trauma in the rat gastrocnemius. Irradiation for 3 or 5 J/cm(2) was initiated 2, 12, and 24 h after muscle trauma induction, and the treatment was continued for five consecutive days. All the oxidant markers investigated. namely thiobarbituric acid-reactive substance, carbonyl, superoxide dismutase, glutathione peroxidase, and catalase, were increased as soon as 2 h after muscle injury and remained increased up to 24 h. These alterations were prevented by LLLT at a 3 J/cm(2) dose given 2 h after the trauma. Similarly, LLLT prevented the trauma-induced proinflammatory state characterized by IL-6 and IL-10. In parallel, trauma-induced reduction in BDNF and VEGF, vascular remodeling and fiber-proliferating markers, was prevented by laser irradiation. In order to test whether the preventive effect of LLLT was also reflected in muscle functionality, we tested the locomotor activity, by measuring distance traveled and the number of rearings in the open field test. LLLT was effective in recovering the normal locomotion, indicating that the irradiation induced biostimulatory effects that accelerated or resolved the acute inflammatory response as well as the oxidant state elicited by the muscle trauma.


Assuntos
Biomarcadores/metabolismo , Inflamação/metabolismo , Músculo Esquelético/metabolismo , Estresse Oxidativo/efeitos da radiação , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Inflamação/fisiopatologia , Interleucina-10/metabolismo , Terapia com Luz de Baixa Intensidade , Músculo Esquelético/lesões , Músculo Esquelético/fisiopatologia , Músculo Esquelético/efeitos da radiação , Ratos , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos da radiação
18.
Neuron ; 86(6): 1393-406, 2015 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-26087165

RESUMO

Human genetic studies have revealed an association between GTP cyclohydrolase 1 polymorphisms, which decrease tetrahydrobiopterin (BH4) levels, and reduced pain in patients. We now show that excessive BH4 is produced in mice by both axotomized sensory neurons and macrophages infiltrating damaged nerves and inflamed tissue. Constitutive BH4 overproduction in sensory neurons increases pain sensitivity, whereas blocking BH4 production only in these cells reduces nerve injury-induced hypersensitivity without affecting nociceptive pain. To minimize risk of side effects, we targeted sepiapterin reductase (SPR), whose blockade allows minimal BH4 production through the BH4 salvage pathways. Using a structure-based design, we developed a potent SPR inhibitor and show that it reduces pain hypersensitivity effectively with a concomitant decrease in BH4 levels in target tissues, acting both on sensory neurons and macrophages, with no development of tolerance or adverse effects. Finally, we demonstrate that sepiapterin accumulation is a sensitive biomarker for SPR inhibition in vivo.


Assuntos
Biopterinas/análogos & derivados , Regulação da Expressão Gênica/fisiologia , Inflamação/metabolismo , Neuralgia/metabolismo , Oxirredutases do Álcool/metabolismo , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Biopterinas/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Modelos Animais de Doenças , Inibidores Enzimáticos/uso terapêutico , GTP Cicloidrolase/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Transgênicos , Neuralgia/induzido quimicamente , Neuralgia/tratamento farmacológico , Medição da Dor , Limiar da Dor/efeitos dos fármacos , Limiar da Dor/fisiologia , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/genética , Nervo Isquiático/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/metabolismo , Sulfassalazina/uso terapêutico , Fatores de Tempo
19.
Rev. bioét. (Impr.) ; 26(2): 217-227, abr.-jun. 2018. tab
Artigo em Português | LILACS | ID: biblio-958260

RESUMO

Resumo Objetivou-se identificar a atitude de profissionais e acadêmicos de enfermagem, fisioterapia, medicina e psicologia de um hospital universitário perante suicídio assistido e eutanásia. O estudo foi desenvolvido por meio de questionário de autopreenchimento e contou com 354 participantes, entre os quais, 68,1% concordaram com a legalização do suicídio assistido e 73,2% com a legalização da eutanásia para pacientes com doenças terminais. A concordância com a legalização do suicídio assistido ou da eutanásia foi de 46,9% em casos de pacientes com doenças neurodegenerativas progressivas e de 30,8% em casos de tetraplegia. Em casos de doenças terminais, se legalizados, 45% dos participantes cometeriam suicídio assistido, 57% solicitariam eutanásia, 36,5% auxiliariam suicídio assistido e 39,9% auxiliariam eutanásia. Conclui-se que a ampla aceitação da legalização da eutanásia e do suicídio assistido entre os participantes enfatiza a necessidade de se ampliar a discussão sobre o tema entre a população.


Abstract The objective of this study was to identify the attitude of professionals and academics in a university hospital regarding assisted suicide and euthanasia. The study was conducted using a questionnaire and included 354 participants. In cases of patients with terminal illnesses, 68.1% of participants supported the legalization of assisted suicide and 73.2% supported the legalization of euthanasia. The support for legalization of assisted suicide or euthanasia was 46.9% in cases of patients with progressive neurodegenerative diseases and 30.8% in cases of tetraplegia. In cases of terminal illnesses, if those were legalized, 45% of participants would commit assisted suicide, 57% would request euthanasia, 36.5% would aid in assisted suicide and 39.9% would aid in euthanasia. In conclusion, the great support for legalization of euthanasia and assisted suicide among the participants emphasizes the need to broaden the discussion on the subject in the population.


Resumen Se tuvo como objetivo identificar la actitud de profesionales y estudiantes de enfermería, fisioterapia, medicina y psicología de un hospital universitario ante el suicidio asistido y la eutanasia. El estudio fue desarrollado por medio de un cuestionario de auto-llenado y contó con 354 participantes, entre los cuales el 68,1% concordó con la legalización del suicidio asistido y el 73,2% con la legalización de la eutanasia para pacientes con enfermedades terminales. La concordancia con la legalización del suicidio asistido o de la eutanasia fue del 46,9% en casos de pacientes con enfermedades neurodegenerativas progresivas y del 30,8% en casos de tetraplejia. En los casos de enfermedades terminales, si se legalizara, el 45% de los participantes practicaría suicidio asistido, el 57% solicitaría eutanasia, el 36,5% colaboraría en el suicidio asistido y el 39,9% colaboraría en la eutanasia. Se concluye que la amplia aceptación de la legalización de la eutanasia y del suicidio asistido entre los participantes enfatiza la necesidad de ampliar la discusión sobre el tema entre la población.


Assuntos
Humanos , Masculino , Feminino , Bioética , Direito a Morrer , Atitude Frente a Morte , Eutanásia , Estado Terminal , Suicídio Assistido , Pessoal de Saúde , Legislação
20.
Rev. bras. oftalmol ; 76(3): 144-149, maio-jun. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-899055

RESUMO

Abstract Purpose: This study aimed to determine the presence of the symptoms of computer vision syndrome (CVS) accounting office employees. Methods: The research tools used were a questionnaire based on the set of symptoms of CVS rated by Likert scale (1-5) and workplace observations based on Ergonomic Workplace Analysis (EWA). Results: The participants who worked with a viewing angle of less than 10º relative to the screen had more symptoms, particularly of pain in the back of the neck and back (p = 0.0460). The participants who used lighting other than 450 and 699 lux reported significant headache (p = 0.0045) and dry eye (p = 0.0329) symptoms. Younger workers had more headaches (p = 0.0182), and workers with fewer years of employment had more headaches and dry eyes symptoms (p = 0.0164 and p = 0.0479, respectively). A total of 37% of the participants reported a lack of guidance regarding prevention and painful symptoms in the back of the neck and back (p = 0.0936). Conclusion: Younger participants with fewer years of employment, who had not received information regarding proper computer use, who did not use lighting between 450 and 699 lux or who worked with viewing angles of less than 10º had more computer vision syndrome symptoms.


Resumo Objetivo: Este trabalho objetivou averiguar a presença dos sintomas da Síndrome Visual dos Computadores (SVC) trabalhadores de escritórios de contabilidade. Métodos: Como instrumentos de pesquisa utilizou-se um questionário baseado no conjunto de sintomas da SVC, avaliado por Escala Likert (1-5), e foram realizadas observações no local de trabalho baseadas na Avaliação Ergonômica de Postos de Trabalho. Resultados: Os participantes que trabalhavam com o ângulo de visão menor do que 10º em relação à tela foram os que apresentaram mais sintomas sobretudo de dor na parte posterior do pescoço e nas costas (p=0,0460). Aqueles que usavam iluminação diferente de 450 e 699 lux reportaram sintomas significativos para dor de cabeça (p=0,0045) e ressecamento ocular (p=0,0329). Os mais jovens apresentaram mais dor de cabeça (p=0,0182) e aqueles com menor tempo de trabalho mais sintomas de dor de cabeça e ressecamento ocular (respectivamente p=0,0164 e p=0,0479). A falta de recebimento de orientações sobre prevenção foi confirmada por 37% participantes que referiram mais sintomas de dor na parte posterior do pescoço e nas costas (p=0,0936). Conclusão: Os participantes mais jovens, com menor tempo de trabalho, que não haviam recebido informações sobre o uso de computador, não utilizavam iluminação entre 450 e 699 lux ou trabalhavam com o ângulo de visão menor do que 10º apresentaram mais sintomas da síndrome visual do computador.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Saúde Ocular , Terminais de Computador , Ergonomia , Transtornos da Visão , Condições de Trabalho , Atitude Frente aos Computadores , Iluminação , Inquéritos e Questionários , Saúde Ocupacional , Local de Trabalho , Doenças Profissionais
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