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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.

BackgroundOral 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.MethodsIn 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.ResultsA 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-1β and IL-10 salivary levels were significantly higher in OC patients compared to controls; and that IL-8, IL-6, TNF-α and IL-1β 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.ConclusionsOur 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.

Several investigators demonstrated that glyphosate formulations produce neurotoxicity associated with oxidative stress, alterations in glutamatergic system, inhibition of acetylcholinesterase activity and mitochondrial dysfunction. However, the underlying molecular mechanisms following exposure to this herbicide on astrocytes are unclear. Thus, the aim of the present study was to determine the activity of enzymes related to energy metabolism, in addition to oxidative stress parameters, mitochondrial mass, nuclear area, and autophagy in astrocytes treated with a glyphosate-based herbicide. Our results showed that 24 h exposure to a glyphosate-based herbicide decreased (1) cell viability, (2) activities of mitochondrial respiratory chain enzymes and creatine kinase (CK), (3) mitochondrial mass, and (4) nuclear area in rat astroglioma cell line (C6 cells). However, non-protein thiol (NPSH) levels were increased but catalase activity was not changed in cells exposed to the herbicide at non-cytotoxic concentrations. Low glyphosate concentrations elevated content of cells positive to autophagy-related proteins. Nuclear factor erythroid 2-related factor (Nrf2), NAD(P)H dehydrogenase [quinone] 1 (NQO1) and PTEN-induced kinase 1 (PINK1) labeling were not markedly altered in cells exposed to glyphosate at the same concentrations that an increase in NPSH levels and positive cells to autophagy were found. It is conceivable that mitochondria and CK may be glyphosate-based herbicides targets. Further, autophagy induction and NPSH increase may be mechanisms initiated to avoid oxidative stress and cell death. However, more studies are needed to clarify the role of autophagy in astrocytes exposed to the herbicide and which components of the formulation might be triggering the effects observed here.

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.

Introdução: O Manganês (Mn) é classificado como um elemento essencial e é essencial para o funcionamento de muitos processos fisiológicos. No entanto, em altas concentrações ou devido à exposição ambiental excessiva, pode vir a causar neurotoxicidade. Muitos agrotóxicos podem ser uma importante fonte desta toxicidade, visto que muitos deles contêm Mn em suas formulações. Neste cenário, torna-se de suma importância determinar o impacto desta substância na saúde humana, já que pesticidas são amplamente utilizados no Brasil e no mundo. Objetivo: Este estudo objetivou mensurar a quantidade de metais, Mn e Ferro (Fe), na dentição decídua de escolares em uma região de Santa Catarina/Brasil e a possível relação com diferentes aspectos de exposição ambiental e hábitos de vida. Metodologia: Foram coletados os dentes decíduos de escolares com faixa etária entre 6 e 12 anos, e mensuradas as concentrações dos metais Mn e Fe através de espectrometria de absorção atômica. Foram incluídos no estudo, indivíduos residentes nas zonas rural e urbana de sete municípios. Além disso, foram coletadas informações qualitativas a respeito de hábitos de vida e exposição ambiental através de questionário aplicado. Resultados: Os resultados do estudo mostraram que não houve diferenças significativas dos níveis dos metais em relação às variáveis analisadas no estudo, como entre os sexos, as zonas de residência, a origem dos alimentos e da água. Conclusão: De acordo com os dados obtidos, pode-se concluir que as concentrações encontradas de Mn não apresentaram relação com os aspectos de exposição ambiental e hábitos de vida, na amostra estudada.

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 OC early detection. Methods: In this systematic review we identified SC studied as OC biomarker 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. Results: A total of 28 articles (from 2004 to 2018) were included, describing 10 different SC, which IL-8 and IL-6 were the most studied ones. SC levels were consistently higher among OC patients when compared to healthy controls and to patients with non-malignant oral conditions such as leukoplakia, lichen planus and gingivitis, irrespective of its inflammatory role. Conclusions: Our analysis suggests SC are consistently up-regulated among OC patients and may represent ideal biomarkers to be translated to the clinical practice.

O Manganes (Mn) e um metal essencial para o organismo. E distribuido no ambiente e utilizado em processos industriais. Apesar de essencial, e neurotoxico a exposicoes cumulativas, causando uma desordem neurologica, o Manganismo. O estudo avaliou o efeito da administracao subaguda de Mn sob a forma de cloreto e acetato de Mn, sobre a funcao mitocondrial e parâmetros oxidativos no encefalo, bem como o acumulo deste metal no encefalo e tecidos perifericos de ratos adultos. Os ratos receberam 6 mg/kg de Mn i.p. na forma de cloreto ou acetato de Mn, 5 dias/semana por 4 semanas. O grupo controle recebeu solucao salina 0,9% pela mesma via de administracao e mesmo periodo. Foi mensurada a concentracao de substâncias reativas ao acido tiobarbiturico (TBARS) e grupamentos NPSH, a atividade dos complexos I e II da cadeia respiratoria no encefalo e/ou estruturas cerebrais, bem como o peso corporal e a concentracao de Mn e Fe no soro, encefalo, tecido renal e hepatico. Foi observada uma diminuicao no ganho de peso corporal dos animais que receberam o Mn, um aumento na concentracao/deposito de Mn no soro, encefalo e tecido renal, tanto na forma de cloreto e acetato de Mn, quando comparados com o grupo controle. Alem disso, houve um aumento significativo no conteudo de NPSH no encefalo e, embora nao significativo, uma tendencia de aumento da concentracao de TBARS, no grupo que recebeu cloreto de Mn. Ainda, foi verificada uma inibicao na atividade do complexo I no estriado dos animais expostos ao cloreto de Mn. Nao houve diferenca entre os grupos nas atividades do complexo I e II no encefalo e hipocampo. Em conjunto, os dados indicam que a exposicao ao Mn em baixas doses contribui para o desenvolvimento de estresse oxidativo e disfuncao mitocondrial no SNC, com aparente predilecao de dano ao estriado. Palavras-chave : Manganes. Exposicao subaguda. Parâmetros oxidativos. Funcao mitocondrial. MANGANESE SUBACUTE INTOXICATION IN ADULT WISTAR RATS: EVALUATION OF OXIDATIVE PARAMETERS IN CNS AND METAL DEPOSITION IN DIFFERENT TISSUES ABSTRACT: Mn is an essential metal to the organism. It is distributed in the environment and used in industrial processes. Although essential, it is neurotoxic to cumulative exposures, and can cause a neurological disorder, called Manganism. This study evaluated the effect of subacute Mn as chloride and acetate of Mn administration on mitochondrial function and oxidative parameters in adult rat brain, as well as the accumulation of this metal in the brain and peripheral tissues. The rats received 6 mg/kg of Mn i.p., as Mn chloride or Mn acetate, 5 days/week for 4 weeks. The control group received 0.9% of saline solution in the same way of administration and in the same period. It was measured the concentration of thiobarbituric acid reactive substances (TBARS) and NPSH groups, the activity of mitochondrial complex I and II in brain and/or in the brain structures, as well as the body weight and the concentration of Mn and Fe accumulation. It was observed a decrease on body weight gain in animals exposed to Mn and an increase of concentration/deposit of Mn in serum, brain and kidney, in the both Mn chloride and acetate form when compared to the control group. In addition, there was a significant increase in brain NPSH content and, although it was not significant, a trend of increasing on TBARS concentration in the group that received Mn. Besides that, a significant inhibition of complex I activity was observed in the striatum of the animals exposed to Mn. There was not difference between groups on complex I and II in the brain and hippocampus. Together, these data indicate that exposure to Mn at low doses contributes to the development of oxidative stress and mitochondrial dysfunction in the CNS, with apparent predilection of striatum damage. Keywords: Manganese. Subacute exposure. Oxidative parameters. Mitochondrial function.

Glyphosate (N-phosphonomethyl-glycine) (GLY) is the active ingredient of the most used herbicides in the world. GLY is applied in formulated products known as glyphosate-based herbicides (GBH), which could induce effects that are not predicted by toxicity assays with pure GLY. This herbicide is classified as organophosphorus compound, which is known to induce neurotoxic effects. Although this compound is classified as non-neurotoxic by regulatory agencies, acute exposure to GBH causes neurological symptoms in humans. However, there is no consensus in relation to neurotoxic effects of GBH. Thus, the aim of this study was to investigate the neurotoxic effects of the GBH in the zebrafish Danio rerio, focusing on acute toxicity, the activity and transcript levels of mitochondrial respiratory chain complexes, mitochondrial membrane potential, reactive species (RS) formation, and behavioral repertoire. Adult zebrafish were exposed in vivo to three concentrations of GBH Scout®, which contained GLY in formulation (fGLY) (0.065, 1.0 and 10.0 mg L−1 fGLY) for 7 d, and an in vitro assay was performed using also pure GLY. Our results show that GBH induced in zebrafish brain a decrease in cell viability, inhibited mitochondrial complex enzymatic activity, modulated gene expression related to mitochondrial complexes, induced an increase in RS production, promoted hyperpolarization of mitochondrial membrane, and induced behavioral impairments. Together, our data contributes to the knowledge of the neurotoxic effects of GBH. Mitochondrial dysfunction has been recognized as a relevant cellular response that should not be disregarded. Moreover, this study pointed to the mitochondria as an important target of GBH.

Uric acid (UA) has been associated with renal fibrosis and progression of chronic kidney disease. However, the underlying mechanisms of this process have still not been identified. Here, we studied the role of the innate imunity receptor NLRP3/ASC in UA induced epithelial-mesenchymal transition (EMT) in kidney. Wistar rats were fed with oxonic acid 2% and UA 2% (OXA + U), OXA + U plus allopurinol (ALL) or regular chow (C) for 7 weeks. We analyzed the presence of EMT markers, the expression of NLRP3, ASC, Caspase-1 and Smad 2/3 molecules and the mitochondrial morphological and functional characteristics. High UA induced renal fibrosis, mild chronic inflammation, as well as morphological and biochemical evidence of EMT. High UA also increased the expression of NLRP3/ASC with activation of both inflammasome related caspase-1 and inflammasome unrelated Smad 2/3 pathways. Ultrastructural co-localization of NLRP3 and Smad 2/3 indicated physical interaction between the two molecules. No morphological or functional changes were found between mitochondria exposed to high UA. In conclusion, kidney epithelial NLRP3/ASC expression was increased in high UA state in rats and both inflammasome related caspase-1 and non-inflammasome related P-Smad 2/3 pathways were associated with the observed EMT, inflammation and fibrosis induced by UA in the kidney. Fil: Romero, Cesar Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Remor, Aline. Universidade Federal de Santa Catarina; Brasil Fil: Latini, Alexandra. Universidade Federal de Santa Catarina; Brasil Fil: de Paul, Ana Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Torres, Alicia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Mukdsi, Jorge Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina

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.

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.

Introduction: Determination of lipid profile includes triglycerides (TG), total cholesterol and fractions as high-density lipoprotein cholesterol (HDL-c) and low-density lipoprotein cholesterol (LDL-c). These parameters are valuable in the risk assessment of developing cardiovascular disease. However, some pre-analytical factors, such as the fasting state, may interfere with the results of these tests. Objective: The aim of this study was to evaluate differences on lipid profile measurements in blood samples collected at different fasting periods in men and women with or without a diagnosis of hypercholesterolemia. Methods: Fifty volunteers of both sexes, aged between 22 and 86 years, were evaluated. Sociodemographic data and two blood samples were collected, one after 12 hours fast and another during postprandial period, with subsequent measurement of total cholesterol, HDL-c, LDL-c and TG. Results: Comparing the values of the lipid profile obtained in the two collections, it was observed that the total cholesterol and HDL-c did not present significant differences among the evaluated subjects. On the other hand, LDL-c and TG showed significant higher values on postprandial samples, preferably in male group. Conclusion: These data suggest that TG and LDL-c levels are the fractions with greater susceptibility to variations when they are collected without prior fasting. RESUMEN Introducción: La determinación del perfil lipídico incluye los triglicéridos (TG), colesterol total y fracciones del colesterol de la lipoproteína de alta densidad (HDL-c) y colesterol de la lipoproteína de baja densidad (LDL-c). Eses parámetros son muy valiosos en la evaluación del riesgo cardiovascular. Sin embargo, algunos factores preanalíticos, como el estado de ayuno, pueden interferir en los resultados de esos exámenes. Objetivo: Evaluar si hay diferencias significativas en la determinación del perfil lipídico en muestras de sangre recolectadas de hombres y mujeres con o sin diagnóstico de hipercolesterolemia. Método: Se evaluaron 50 voluntarios de ambos sexos, con edades comprendidas entre 22 y 86 años. Se recolectaron informaciones sociodemográficas y dos muestras de sangre, una con ayuno previo de 12 horas y otra posprandial, con determinación posterior de colesterol total, HDL-c, LDL-c, y TG. Resultados: Comparándose los valores obtenidos del perfil lipídico en las dos coletas, se observó que el colesterol total y el HDL-c no presentaron diferencias significativas en los sujetos evaluados. Al mismo tiempo, LDL-c y TG mostraron valores significativamente más elevados en la recolecta posprandial, preferencialmente en el grupo masculino. Conclusión: El conjunto de datos obtenidos sugiere que los niveles de TG y LDL-c son las fracciones con mayor susceptibilidad a variaciones cuando son recolectadas sin ayuno previo. RESUMO Introdução: A determinação do perfil lipídico inclui dosagens de triglicerídeos (TG), colesterol total e frações do colesterol da lipoproteína de alta densidade (HDL-c) e do colesterol da lipoproteína de baixa densidade (LDL-c). Esses parâmetros são muito valiosos na avaliação do risco do desenvolvimento de doenças cardiovasculares. Porém, alguns fatores pré-analíticos, como o estado de jejum, podem interferir nos resultados desses exames. Objetivo: Avaliar se existem diferenças significativas nas dosagens do perfil lipídico em amostras de sangue coletadas em diferentes períodos de jejum em homens e mulheres com ou sem diagnóstico de hipercolesterolemia. Método: Foram avaliados 50 voluntários de ambos os sexos, com faixa etária entre 22 e 86 anos. Foram coletadas informações sociodemográficas e duas amostras de sangue, uma com jejum prévio de 12 horas e outra pós-prandial, com posterior dosagem de colesterol total, HDL-c, LDL-c e TG. Resultados: Ao comparar os valores obtidos do perfil lipídico nas duas coletas, observou-se que o colesterol total e o HDL-c não apresentaram diferenças significativas nos sujeitos avaliados. Por outro lado, o LDL-c e o TG expressaram valores significativamente mais elevados na coleta realizada de forma pós-prandial, preferencialmente no grupo masculino. Conclusão: O conjunto dos dados obtidos sugere que os níveis de TG e LDL-c são as frações com maior suscetibilidade a variações quando são coletadas sem jejum prévio.

Introduction: Obesity is associated with the development of metabolic disorders that can be diagnosed through inflammatory and oxidative biomarkers. Background: This study evaluated the influence of obesity and overweight on serum concentrations of vitamins C and E, transforming growth factor beta 1 (TGF-β1) and cardiometabolic parameters. Methods: A cross-sectional study was conducted with 169 participants (24 normal weight, 16 overweight and 129 obese). Anthropometric measures and concentrations of vitamins C and E, thiobarbituric acid reactive substances (TBARS), TGF-β1, lipid profile, glycated hemoglobin (HbA1c), glucose and insulin were determined, and homeostatic model assessment of insulin resistance (HOMA-IR) and insulin sensitivity (IS) were calculated. Results: Obese and overweight participants showed significantly higher levels of TGF-β1, vitamin E, insulin, HbA1c, glucose, cholesterol, low-density lipoprotein cholesterol (LDL-c), triglycerides, HOMA-IR, and TBARS compared with normal weight patients, associated with a significant reduction in IS, high-density lipoprotein cholesterol (HDL-c), and vitamin C. Conclusion: Obesity and overweight may lead to significant changes in TGF-B1, biochemical and oxidative markers. Increased levels of TGF-β1 may promote inflammation and interfere with IS. Reduced concentrations of vitamin C and increased levels of TBARS led to a redox imbalance in obese and overweight patients, suggesting that vitamin E is not a promising oxidative biomarker since it is lipophilic and its concentration is influenced by body fat. These results may help determine the oxidative and inflammatory pathways related to obesity and its comorbidities. Keywords: Obesity; vitamins; antioxidants; metabolism

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.

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.

The cellular transformation of normal functional cells to neoplastic ones implies alterations in the cellular metabolism and mitochondrial function in order to provide the bioenergetics and growth requirements for tumour growth progression. Currently, the mitochondrial physiology and dynamic shift during pituitary tumour development are not well understood. Pituitary tumours present endocrine neoplastic benign growth which, in previous reports, we had shown that in addition to increased proliferation, these tumours were also characterized by cellular senescence signs with no indication of apoptosis. Here, we show clear evidence of oxidative stress in pituitary cells, accompanied by bigger and round mitochondria during tumour development, associated with augmented biogenesis and an increased fusion process. An activation of the Nrf2 stress response pathway together with the attenuation of the oxidative damage signs occurring during tumour development were also observed which will probably provide survival advantages to the pituitary cells. These neoplasms also presented a progressive increase in lactate production, suggesting a metabolic shift towards glycolysis metabolism. These findings might imply an oxidative stress state that could impact on the pathogenesis of pituitary tumours. These data may also reflect that pituitary cells can modulate their metabolism to adapt to different energy requirements and signalling events in a pathophysiological situation to obtain protection from damage and enhance their survival chances. Thus, we suggest that mitochondria function, oxidative stress or damage might play a critical role in pituitary tumour progression. Fil: Sabatino, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Grondona, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Sosa, Liliana del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Mongi Bragato, Bethania del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Carreño, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Juarez, Andrea Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: da Silva, Rodrigo A.. Universidad Federal de Santa Catarina, Brasil; Brasil Fil: Remor, Aline. Universidad Federal de Santa Catarina, Brasil; Brasil Fil: de Bortoli, Lucila. Universidad Federal de Santa Catarina, Brasil; Brasil Fil: Paula Martins, Roberta de. Universidad Federal de Santa Catarina, Brasil; Brasil Fil: Pérez, Pablo Aníbal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Microscopía Electrónica; Argentina Fil: Petiti, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Microscopía Electrónica; Argentina Fil: Gutiérrez, Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Microscopía Electrónica; Argentina Fil: Torres, Alicia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Microscopía Electrónica; Argentina Fil: Latini, Alexandra. Universidad Federal de Santa Catarina, Brasil; Brasil Fil: de Paul, Ana Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Microscopía Electrónica; Argentina

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. Fil: Remor, Aline Pertile. Universidade Federal de Santa Catarina; Brasil. Universidade do Oeste de Santa Catarina; Brasil Fil: Da Silva, Rodrigo Augusto. Universidade Federal de Santa Catarina; Brasil. Universidade Estadual de São Paulo; Brasil Fil: de Matos, Filipe José. Universidade Federal de Santa Catarina; Brasil Fil: Glaser, Viviane. Universidade Federal de Santa Catarina; Brasil Fil: Paula Martins, Roberta de. Universidade Federal de Santa Catarina; Brasil Fil: Ghisoni, Karina. Universidade Federal de Santa Catarina; Brasil Fil: Luz Scheffer, Débora da. Universidade Federal de Santa Catarina; Brasil Fil: Andia, Denise Carleto. Universidade Paulista. Faculdade de Odontologia. Área de Pesquisa em Epigenética; Brasil Fil: Portinho, Daniele. Universidade Estadual de São Paulo; Brasil Fil: de Souza, Ana Paula. Universidade Estadual de São Paulo; Brasil Fil: Oliveira, Paulo Alexandre de. Universidade Federal de Santa Catarina; Brasil Fil: Prediger, Rui Daniel. Universidade Federal de Santa Catarina; Brasil Fil: Torres, Alicia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Microscopía Electrónica; Argentina Fil: Linhares, Rose Marie Mueller. Universidade Federal de Santa Catarina; Brasil. Hospital Infantil Joana de Gusmão; Brasil Fil: Walz, Roger. Universidade Federal de Santa Catarina; Brasil Fil: Ronsoni, Marcelo Fernando. Universidade Federal de Santa Catarina; Brasil Fil: Hohl, Alexandre. Universidade Federal de Santa Catarina; Brasil Fil: Rafacho, Alex. Universidade Federal de Santa Catarina; Brasil Fil: Aguiar, Aderbal Silva. Universidade Federal de Santa Catarina; Brasil Fil: de Paul, Ana Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Microscopía Electrónica; Argentina Fil: Latini, Alexandra. Universidade Federal de Santa Catarina; Brasil. Harvard Medical School; Estados Unidos

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.

SummaryHuman 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.Video 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.

The present study was aimed at analyzing the effects of physical exercise on mitochondrial physiology, anxio-depressive-like behaviors and neuroplasticity in mice. Adult C57BL/6J male mice were isolated in home cages equipped or not with free-running wheels. After 6weeks of exercise, mice were tested in various behavioral paradigms to evaluate anxiety- and depressive-like behaviors. The hippocampi were dissected for neurochemical assays, including mitochondrial activity, monoamines content and the expression of genes involved in energy metabolism and brain-derived neurotrophic factor (BDNF) regulation. Exercise decreased anxiety-like behaviors in the open field and elevated plus maze, and exerted antidepressant-like effects in the tail suspension test. Exercise stimulated brain mitochondrial activity and increased resistance against rotenone, an inhibitor of complex I activity. Furthermore, mRNA expression of Bdnf, Gdnf, Tfam (mitochondrial transcription factor A), and Ndufa6 (mitochondrial I subunit) genes, as well as the phosphorylation of cAMP response element-binding protein were increased after exercise. In summary, exercise appears to engage mitochondrial pathways and to potentiate neuroplasticity and might be associated to mood improvement.

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.

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-1β 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-1β, 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-1β 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.

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.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.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.In mice, exercise activated Nrf2-ARE signaling in the nigrostriatal pathway that was protective against the development of hemiparkinsonism.

Here we showed that persistent hyperglycemia, a hallmark of some chronic metabolic diseases promotes epigenetic changes in the CNS that convey in higher susceptibility to neurodegeneration, compromising learning and memory. In order to investigate of impact of chronic hyperglycemia (10 or 60 days) on these neurochemical and behavioral parameters, Wistar rats received a single intraperitoneal injection of 55 mg/kg streptozotocin (STZ). Some rats also receive also insulin to control glycaemia (INS; 1.5 IU; human insulin NPH; Novolin®N twice a day). Hyperglycemia treatment compromised short- and long-term memory, as well as spatial memory, effect that was accompanied by significant CSF and plasma oxidative stress. Insulin expression was markedly reduced in the hippocampus, but with normal canonical insulin/insulin-like signaling. Oxygen consumption experiments showed uncoupled mitochondria with increased expression of complex I (NDUFA6), probably as a compensatory response to the mitochondrial stress elicited by the excess of nutrients. Furthermore, the hyperglycemic state induced a subcellular redistribution of hippocampal α-synuclein, even when the total content of the protein remained unchanged. Hippocampus was also depicted by marked reduction of IL-10 expression, increased GFAP expression, reduced content of BDNF and increased caspase-3 activation. This neurotoxic environment occurred in parallel with a specific and significant global DNA hypermethylation and hypomethylation of LINE-1 region (genome instability) in STZ rats. DNA hypermethylation affected the expression of REST, a neurocognitive transcription factor in the adult brain, which was significantly decreased in the hippocampus of STZ rats. In agreement, REST promoter was also hypermethylated. In contrast, the gene expression of the truncate toxic splice variant REST4 was significantly up-regulated. INS administration efficiently prevented all these epigenetic alterations and the cognitive impairments. It could be concluded that controlling glucose homeostasis, mainly in the elderly, could reduce the risk of the development of cognitive impairment and neurodegenerative diseases.

Manganese (Mn) is an essential metal for development and metabolism. However, exposures to high Mn levels may be toxic, especially to the central nervous system (CNS). Neurotoxicity is commonly due to occupational or environmental exposures leading to Mn accumulation in the basal ganglia and a Parkinsonian-like disorder. Younger individuals are more susceptible to Mn toxicity. Moreover, early exposure may represent a risk factor for the development of neurodegenerative diseases later in life. The present study was undertaken to investigate the developmental neurotoxicity in an in vivo model of immature rats exposed to Mn (5, 10 and 20 mg/kg; i.p.) from postnatal day 8 (PN8) to PN12. Neurochemical analysis was carried out on PN14. We focused on striatal alterations in intracellular signaling pathways, oxidative stress and cell death. Moreover, motor alterations as a result of early Mn exposure (PN8-12) were evaluated later in life at 3-, 4- and 5-weeks-of-age. Mn altered in a dose-dependent manner the activity of key cell signaling elements. Specifically, Mn increased the phosphorylation of DARPP-32-Thr-34, ERK1/2 and AKT. Additionally, Mn increased reactive oxygen species (ROS) production and caspase activity, and altered mitochondrial respiratory chain complexes I and II activities. Mn (10 and 20 mg/kg) also impaired motor coordination in the 3(rd), 4(th) and 5(th) week of life. Trolox™, an antioxidant, reversed several of the Mn altered parameters, including the increased ROS production and ERK1/2 phosphorylation. However, Trolox™ failed to reverse the Mn (20 mg/kg)-induced increase in AKT phosphorylation and motor deficits. Additionally, Mn (20 mg/kg) decreased the distance, speed and grooming frequency in an open field test; Trolox™ blocked only the decrease of grooming frequency. Taken together, these results establish that short-term exposure to Mn during a specific developmental window (PN8-12) induces metabolic and neurochemical alterations in the striatum that may modulate later-life behavioral changes. Furthermore, some of the molecular and behavioral events, which are perturbed by early Mn exposure are not directly related to the production of oxidative stress.

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 30days 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 10days 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 (30days) 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.