RESUMEN
La pandemia debido al coronavirus 2019 (COVID-19) y los períodos de confinamiento impactaron negativamente en el estado de ánimo, la salud y la calidad de vida. Este estudio evaluó el impacto de los períodos de confinamiento en Argentina sobre la capacidad inmunológica, es decir, la capacidad del cuerpo para responder a desafíos de salud (como infecciones) a través de la activación de una respuesta inmunológica apropiada, y la calidad del sueño de los estudiantes universitarios de Buenos Aires. Una encuesta retrospectiva entre estudiantes (N=482, 29.3% varones, con una edad promedio (DS) de 22.6 (3.5) años) reveló que, tanto la aptitud inmunológica como la calidad del sueño fueron significativamente peores durante la pandemia de la COVID-19 (p < 0.001). Los efectos fueron más pronunciados durante los períodos de confinamiento. No se encontraron diferencias relevantes debidas al sexo y la edad. En conclusión, los períodos de confinamiento por COVID-19 tuvieron un impacto negativo significativo en la capacidad inmunológica y en la calidad del sueño. Esta observación es preocupante, ya que investigaciones previas mostraron que una aptitud inmunológica deficiente está asociada con experimentar síntomas más graves de la enfermedad por COVID-19 cuando se está infectado con el virus SARS-CoV-2.
The 2019 coronavirus disease (COVID-19) pandemic and associated lockdown periods had a significant negative impact on mood, health, and quality of life. This study evaluated to what extent the lockdown periods in Argentina had an impact on immune fitness, i.e., the body's capacity to respond to health challenges (such as infections) by activating an appropriate immune response, and sleep quality of university students in Buenos Aires. A retrospective survey among students (N=482, 29.3% males, mean (SD) age of 22.6 (3.5) years old) revealed that, compared to before COVID-19, both immune fitness and sleep quality were significantly poorer during the COVID-19 pandemic (p < 0.001). The effects were most pronounced during the lockdown periods. No relevant sex and age differences were found. In conclusion, the COVID-19 lockdown periods had a significant negative impact on immune fitness and sleep quality. This observation is of concern, as previous research showed that a poor immune fitness is associated with experiencing more severe COVID-19 symptoms when infected with SARS-CoV-2.
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Humanos , Calidad de Vida/psicología , Cuarentena/psicología , COVID-19/inmunología , Calidad del Sueño , Inmunidad/inmunologíaRESUMEN
Alcohol hangover is the combination of negative mental and physical symptoms which can be experienced after a single episode of alcohol consumption, starting when blood alcohol concentration approaches zero. We previously demonstrated that hangover provokes mitochondrial dysfunction, oxidative stress, imbalance in antioxidant defenses, and impairment in cellular bioenergetics. Chronic and acute ethanol intake induces neuroapoptosis but there are no studies which evaluated apoptosis at alcohol hangover. The aim of the present work was to study alcohol residual effects on intrinsic and extrinsic apoptotic signaling pathways in mice brain cortex. Male Swiss mice received i.p. injection of ethanol (3.8 g/kg) or saline. Six hours after injection, at alcohol hangover onset, mitochondria and tissue lysates were obtained from brain cortex. Results indicated that during alcohol hangover a loss of granularity of mitochondria and a strong increment in mitochondrial permeability were observed, indicating the occurrence of swelling. Alcohol-treated mice showed a significant 35% increase in Bax/Bcl-2 ratio and a 5-fold increase in the ratio level of cytochrome c between mitochondria and cytosol. Caspase 3, 8 and 9 protein expressions were 32%, 33% and 20% respectively enhanced and the activity of caspase 3 and 6 was 30% and 20% increased also due to the hangover condition. Moreover, 38% and 32% increments were found in PARP1 and p53 protein expression respectively and on the contrary, SIRT-1 was almost 50% lower than controls due to the hangover condition. The present work demonstrates that alcohol after-effects could result in the activation of mitochondrial and non-mitochondrial apoptosis pathways.
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Intoxicación Alcohólica , Etanol , Masculino , Animales , Ratones , Etanol/toxicidad , Caspasa 3/metabolismo , Nivel de Alcohol en Sangre , Intoxicación Alcohólica/metabolismo , Encéfalo/metabolismo , Apoptosis , Transducción de SeñalRESUMEN
Mitochondrial function at synapses can be assessed in isolated nerve terminals. Synaptosomes are structures obtained in vitro by detaching the nerve endings from neuronal bodies under controlled homogenization conditions. Several protocols have been described for the preparation of intact synaptosomal fractions. Herein a fast and economical method to obtain synaptosomes with optimal intrasynaptic mitochondria functionality was described. Synaptosomal fractions were obtained from mouse brain cortex by differential centrifugation followed by centrifugation in a Ficoll gradient. The characteristics of the subcellular particles obtained were analyzed by flow cytometry employing specific tools. Integrity and specificity of the obtained organelles were evaluated by calcein and SNAP-25 probes. The proportion of positive events of the synaptosomal preparation was 75 ± 2 % and 48 ± 7% for calcein and Synaptosomal-Associated Protein of 25 kDa (SNAP-25), respectively. Mitochondrial integrity was evaluated by flow cytometric analysis of cardiolipin content, which indicated that 73 ± 1% of the total events were 10 N-nonylacridine orange (NAO)-positive. Oxygen consumption, ATP production and mitochondrial membrane potential determinations showed that mitochondria inside synaptosomes remained functional after the isolation procedure. Mitochondrial and synaptosomal enrichment were determined by measuring synaptosomes/ homogenate ratio of specific markers. Functionality of synaptosomes was verified by nitric oxide detection after glutamate addition. As compared with other methods, the present protocol can be performed briefly, does not imply high economic costs, and provides an useful tool for the isolation of a synaptosomal preparation with high mitochondrial respiratory capacity and an adequate integrity and function of intraterminal mitochondria.
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Mitocondrias , Sinaptosomas , Ratones , Animales , Sinaptosomas/química , Sinaptosomas/metabolismo , Sinaptosomas/ultraestructura , Mitocondrias/metabolismo , Metabolismo Energético , Encéfalo/metabolismo , Corteza CerebralRESUMEN
In Argentina, the 2019 coronavirus disease (COVID-19) pandemic led to serious changes to social interaction, health, economy, and education. Argentina experienced two extensive lockdown periods. University education remained virtual for almost two academic years. The purpose of the present work was to analyze the impact of the COVID-19 lockdowns in Argentina on alcohol consumption, hangover severity and smoking among university students in Buenos Aires. A retrospective online survey was conducted in 2021 among students of the University of Buenos Aires. Participants aged 18-35 years old were asked about the average number of alcoholic drinks and number of drinking days per week, binge drinking occasions, drunkenness, next day hangover severity, number of hangovers per month, and smoking behavior. The results showed that the first and second COVID-19 lockdowns were associated with significant reductions in both weekly alcohol consumption, and hangover severity and subjective intoxication on their heaviest drinking occasions. Males consumed significantly more alcohol than females, and older students (25-35 years old) consumed more alcohol than younger students (18-24 years old). In addition, younger students reduced the number of cigarettes smoked per day during the two lockdown periods while older students exhibited significantly more smoking days per week. In conclusion, the present work in Argentinian students revealed a significant reduction in weekly alcohol consumption, and subjective intoxication and hangover severity on their heaviest drinking occasions during the pandemic lockdown periods.
RESUMEN
Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) has been described as a potential toxic for dopaminergic metabolism both in vivo and in vitro. Its main metabolite diamino-chloro triazine (DACT) has been shown to achieve higher levels in brain tissue than atrazine. The aim of this study was to evaluate the in vitro effects of atrazine and DACT on striatal mitochondrial function, active oxygen species generation, and nitric oxide (NO) content. Incubation of mitochondria with atrazine (10 µM) was not able to modify oxygen consumption. However, a 50% increase in malate-glutamate state 4 respiratory rates was observed after DACT treatment (100 µM) without changes in respiratory state 3. Atrazine was able to inhibit complex I-III activity by 30% and DACT induced a tendency to decrease by 17% in the striatum. Regarding reactive oxygen species (ROS), DACT increased H2 O2 production by 43%. Also, superoxide anion levels were higher (14%) after atrazine exposure than in control mitochondria. Incubation of striatal mitochondria with atrazine and DACT induced membrane depolarization by 15% and 19%, respectively. Also, atrazine increased NO content by 10% but no significant changes were observed after exposure of mitochondria to DACT. Glutathione peroxidase activity was inhibited (56%) by DACT and atrazine inhibited superoxide dismutase activity by 60%. Also, cardiolipin oxidation (15%) was observed after atrazine treatment. Summing up, the obtained results suggest that in vitro atrazine and DACT induce ROS production affecting striatal mitochondrial function. The atrazine effects would be attributed to a direct effect on the mitochondrial respiratory chain and superoxide dismutase activity while DACT appears to disturb glutathione-related enzyme system.
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Atrazina , Herbicidas , Atrazina/toxicidad , Atrazina/metabolismo , Herbicidas/toxicidad , Especies Reactivas de Oxígeno , Triazinas/farmacología , Superóxido Dismutasa , Mitocondrias/metabolismoRESUMEN
Alcohol hangover is defined as the combination of mental and physical symptoms experienced the day after a single episode of heavy drinking, starting when blood alcohol concentration approaches zero. We previously evidenced increments in free radical generation and an imbalance in antioxidant defences in non-synaptic mitochondria and synaptosomes during hangover. It is widely known that acute alcohol exposure induces changes in nitric oxide (NO) production and blocks the binding of glutamate to NMDAR in central nervous system. Our aim was to evaluate the residual effect of acute ethanol exposure (hangover) on NO metabolism and the role of NMDA receptor-PSD95-nNOS pathway in non-synaptic mitochondria and synaptosomes from mouse brain cortex. Results obtained for the synaptosomes fraction showed a 37% decrease in NO total content, a 36% decrease in NOS activity and a 19% decrease in nNOS protein expression. The in vitro addition of glutamate to synaptosomes produced a concentration-dependent enhancement of NO production which was significantly lower in samples from hangover mice than in controls for all the glutamate concentrations tested. A similar patter of response was observed for nNOS activity being decreased both in basal conditions and after glutamate addition. In addition, synaptosomes exhibited a 64% and 15% reduction in NMDA receptor subunit GluN2B and PSD-95 protein expression, respectively. Together with this, glutamate-induced calcium entry was significant decreased in synaptosomes from alcohol-treated mice. On the other hand, in non-synaptic mitochondria, no significant differences were observed in NO content, NOS activity or nNOS protein expression. The expression of iNOS remained unaltered in synaptosomes and non-synaptic mitochondria. Here we demonstrated that hangover effects on NO metabolism are strongly evidenced in synaptosomes probably due to a disruption in NMDAR/PSD-95/nNOS pathway.
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Intoxicación Alcohólica/metabolismo , Homólogo 4 de la Proteína Discs Large/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Óxido Nítrico/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animales , Homólogo 4 de la Proteína Discs Large/genética , Masculino , Ratones , Óxido Nítrico/análisis , Óxido Nítrico Sintasa de Tipo I/genéticaRESUMEN
NEW FINDINGS: What is the central question of this study? In adult rat hearts, exposure to hypobaric hypoxia increases tolerance to hypoxia-reoxygenation, termed endogenous cardioprotection. The mechanism involves the nitric oxide system and modulation of mitochondrial oxygen consumption. What is the cardiac energetic response in prepubertal rats exposed to hypobaric hypoxia? What is the main finding and its importance? Prepubertal rats, unlike adult rats, did not increase tolerance to hypoxia-reoxygenation in response acute exposure to hypobaric hypoxia, which impaired cardiac contractile economy. This finding could be related to a failure to increase nitric oxide synthase expression, hence modulation of mitochondrial oxygen consumption and ATP production. ABSTRACT: Studies in our laboratory showed that exposure of rats to hypobaric hypoxia (HH) increased the tolerance of the heart to hypoxia-reoxygenation (H/R), involving mitochondrial and cytosolic nitric oxide synthase (NOS) systems. The objective of the present study was to evaluate how the degree of somatic maturation could alter this healthy response. Prepubertal male rats were exposed for 48 h to a simulated altitude of 4400 m in a hypobaric chamber. The mechanical energetic activity in perfused hearts and the contractile functional capacity of NOS in isolated left ventricular papillary muscles were evaluated during H/R. Cytosolic nitric oxide (NO), production of nitrites/nitrates (Nx), expression of NOS isoforms, mitochondrial O2 consumption and ATP production were also evaluated. The left ventricular pressure during H/R was not improved by HH. However, the energetic activity was increased. Thus, the contractile economy (left ventricular pressure/energetic activity) decreased in HH. Nitric oxide did not modify papillary muscle contractility after H/R. Cytosolic p-eNOS-Ser1177 and inducible NOS expression were decreased by HH, but no changes were observed in NO production. Interestingly, HH increased Nx levels, but O2 consumption and ATP production in mitochondria were not affected by HH. Prepubertal rats exposed to HH preserved cardiac contractile function, but with a high energetic cost, modifying contractile economy. Although this could be related to the decreased NOS expression detected, cytosolic NO production was preserved, maybe through the Nx metabolic pathway, without modification of mitochondrial ATP production and O2 consumption. In this scenario, the treatment was unable to increase tolerance to H/R as observed in adult animals.
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Hipoxia , Óxido Nítrico , Altitud , Animales , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/metabolismo , Ratas , Ratas WistarRESUMEN
Previous reports have shown that ketamine triggered apoptosis in immature developing brain involving mitochondrial-mediated pathways. However, no data for ketamine effects on hippocampal and cortical mitochondrial function are available in prepubertal rats. Twenty-one-day-old Sprague-Dawley rats received ketamine (40 mg/kg i.p.) for 3 days and were killed 24 hr after the last injection. Hippocampal mitochondria from ketamine-treated rats showed decreased malate-glutamate state 4 and 3 respiratory rates and an inhibition in complex I and IV activities. Hippocampal mitochondrial membrane depolarization and mitochondrial permeability transition induction were observed. This was not reflected in an increment of H2 O2 production probably due to increased Mn-SOD and catalase activities, 24 hr after treatment. Interestingly, increased H2 O2 production rates and cardiolipin oxidation were found in hippocampal mitochondria shortly after ketamine treatment (45 min). Unlike the hippocampus, ketamine did not affect mitochondrial parameters in the brain cortex, being the area less vulnerable to suffer ketamine-induced oxidative damage. Results provide evidences that exposure of prepubertal rats to ketamine leads to an induction of mitochondrial ROS generation at early stages of treatment that was normalized by the triggering of antioxidant systems. Although hippocampal mitochondria from prepubertal rats were capable of responding to the oxidative stress, they remain partially dysfunctional.
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Corteza Cerebral/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/farmacología , Hipocampo/efectos de los fármacos , Ketamina/farmacología , Mitocondrias/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Catalasa/metabolismo , Corteza Cerebral/metabolismo , Ácido Glutámico/metabolismo , Hipocampo/metabolismo , Malatos/metabolismo , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Superóxido Dismutasa/metabolismoRESUMEN
Alcohol hangover (AH) has been associated with oxidative stress and mitochondrial dysfunction. We herein postulate that AH-induced mitochondrial alterations can be due to a different pattern of response in synaptosomes and non-synaptic (NS) mitochondria. Mice received intraperitoneal (i.p.) injections of ethanol (3.8 g/kg) or saline and were sacrificed 6 h afterward. Brain cortex NS mitochondria and synaptosomes were isolated by Ficoll gradient. Oxygen consumption rates were measured in NS mitochondria and synaptosomes by high-resolution respirometry. Results showed that NS-synaptic mitochondria from AH animals presented a 26% decrease in malate-glutamate state 3 respiration, a 64% reduction in ATP content, 28-37% decrements in ATP production rates (malate-glutamate or succinate-dependent, respectively), and 44% inhibition in complex IV activity. No changes were observed in mitochondrial transmembrane potential (ΔΨ) or in UCP-2 expression in NS-mitochondria. Synaptosome respiration driving proton leak (in the presence of oligomycin), and spare respiratory capacity (percentage ratio between maximum and basal respiration) were 30% and 15% increased in hangover condition, respectively. Synaptosomal ATP content was 26% decreased, and ATP production rates were 40-55% decreased (malate-glutamate or succinate-dependent, respectively) in AH mice. In addition, a 24% decrease in ΔΨ and a 21% increase in UCP-2 protein expression were observed in synaptosomes from AH mice. Moreover, mitochondrial respiratory complexes I-III, II-III, and IV activities measured in synaptosomes from AH mice were decreased by 18%, 34%, and 50%, respectively. Results of this study reveal that alterations in bioenergetics status during AH could be mainly due to changes in mitochondrial function at the level of synapses.
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Consumo Excesivo de Bebidas Alcohólicas/metabolismo , Corteza Cerebral/metabolismo , Metabolismo Energético/fisiología , Etanol/toxicidad , Mitocondrias/metabolismo , Sinaptosomas/metabolismo , Intoxicación Alcohólica/metabolismo , Animales , Corteza Cerebral/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Masculino , Ratones , Mitocondrias/efectos de los fármacos , Sinaptosomas/efectos de los fármacosRESUMEN
Neurotensin is known to inhibit neuronal Na+ , K+ -ATPase, an effect that is rescued by nitric oxide (NO) synthase inhibition. However, whether the neurotensinergic and the nitrergic systems are independent pathways, or are mechanistically linked, remains unknown. Here, we addressed this issue and found that the administration of low affinity neurotensin receptor (NTS2) antagonist, levocabastine (50 µg/kg, i.p.) inhibited NO synthase (NOS) activity by 74 and 42% after 18 h in synaptosomal and mitochondrial fractions isolated from the Wistar rat cerebral cortex, respectively; these effects disappeared 36 h after levocabastine treatment. Intriguingly, whereas neuronal NOS protein abundance decreased (by 56%) in synaptosomes membranes, it was enhanced (by 86%) in mitochondria 18 h after levocabastine administration. Levocabastine enhanced the respiratory rate of synaptosomes in the presence of oligomycin, but it failed to alter the spare respiratory capacity; furthermore, the mitochondrial respiratory chain (MRC) complexes I-IV activities were severely diminished by levocabastine administration. The inhibition of NOS and MRC complexes activities were also observed after incubation of synaptosomes and mitochondria with levocabastine (1 µM) in vitro. These data indicate that the NTS2 antagonist levocabastine regulates NOS expression and activity at the synapse, suggesting an interrelationship between the neurotensinergic and the nitrergic systems. However, the bioenergetics effects of NTS2 activity inhibition are likely to be independent from the regulation of NO synthesis.
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Encéfalo/efectos de los fármacos , Antagonistas de los Receptores Histamínicos H1 no Sedantes/farmacología , Mitocondrias/efectos de los fármacos , Óxido Nítrico/biosíntesis , Piperidinas/farmacología , Animales , Encéfalo/metabolismo , Masculino , Óxido Nítrico Sintasa/metabolismo , Ratas , Ratas Wistar , Receptores de Neurotensina/antagonistas & inhibidoresRESUMEN
Alcohol hangover (AH) is the pathophysiological state after a binge-like drinking. We have previously demonstrated that AH induced bioenergetics impairments in a total fresh mitochondrial fraction in brain cortex and cerebellum. The aim of this work was to determine free radical production and antioxidant systems in non-synaptic mitochondria and synaptosomes in control and hangover animals. Superoxide production was not modified in non-synaptic mitochondria while a 17.5% increase was observed in synaptosomes. A similar response was observed for cardiolipin content as no changes were evidenced in non-synaptic mitochondria while a 55% decrease in cardiolipin content was found in synaptosomes. Hydrogen peroxide production was 3-fold increased in non-synaptic mitochondria and 4-fold increased in synaptosomes. In the presence of deprenyl, synaptosomal H2O2 production was 67% decreased in the AH condition. Hydrogen peroxide generation was not affected by deprenyl addition in non-synaptic mitochondria from AH mice. MAO activity was 57% increased in non-synaptic mitochondria and 3-fold increased in synaptosomes. Catalase activity was 40% and 50% decreased in non-synaptic mitochondria and synaptosomes, respectively. Superoxide dismutase was 60% decreased in non-synaptic mitochondria and 80% increased in synaptosomal fractions. On the other hand, GSH (glutathione) content was 43% and 17% decreased in synaptosomes and cytosol. GSH-related enzymes were mostly affected in synaptosomes fractions by AH condition. Acetylcholinesterase activity in synaptosomes was 11% increased due to AH. The present work reveals that AH provokes an imbalance in the cellular redox homeostasis mainly affecting mitochondria present in synaptic terminals.
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Trastornos del Sistema Nervioso Inducidos por Alcohol/metabolismo , Corteza Cerebral/patología , Radicales Libres/metabolismo , Mitocondrias/metabolismo , Terminales Presinápticos/metabolismo , Acetilcolinesterasa/metabolismo , Animales , Cardiolipinas/metabolismo , Metabolismo Energético , Etanol/toxicidad , Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Masculino , Potencial de la Membrana Mitocondrial , Ratones , Oxidación-Reducción , Terminales Presinápticos/patología , Superóxidos/metabolismo , Sinaptosomas/metabolismoRESUMEN
Alterations in mitochondrial bioenergetics have been associated with brain aging. In order to evaluate the susceptibility of brain cortex synaptosomes and non-synaptic mitochondria to aging-dependent dysfunction, male Swiss mice of 3 or 17 months old were used. Mitochondrial function was evaluated by oxygen consumption, mitochondrial membrane potential and respiratory complexes activity, together with UCP-2 protein expression. Basal respiration and respiration driving proton leak were decreased by 26 and 33 % in synaptosomes from 17-months old mice, but spare respiratory capacity was not modified by aging. Succinate supported state 3 respiratory rate was decreased by 45 % in brain cortex non-synaptic mitochondria from 17-month-old mice, as compared with young animals, but respiratory control was not affected. Synaptosomal mitochondria would be susceptible to undergo calcium-induced depolarization in 17 months-old mice, while non-synaptic mitochondria would not be affected by calcium overload. UCP-2 was significantly up-regulated in both synaptosomal and submitochondrial membranes from 17-months old mice, compared to young animals. UCP-2 upregulation seems to be a possible mechanism by which mitochondria would be resistant to suffer oxidative damage during aging.
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Envejecimiento/metabolismo , Corteza Cerebral/metabolismo , Metabolismo Energético , Mitocondrias/metabolismo , Sinaptosomas/metabolismo , Animales , Calcio/metabolismo , Masculino , Potencial de la Membrana Mitocondrial , RatonesRESUMEN
Mitochondrial dysfunction has been implicated in many diseases, including diabetes. It is well known that oxygen free radical species are produced endogenously by mitochondria, and also nitric oxide (NO) by nitric oxide synthases (NOS) associated to mitochondrial membranes, in consequence these organelles constitute main targets for oxidative damage. The aim of this study was to analyze mitochondrial physiology and NO production in brain cortex mitochondria of streptozotocin (STZ) diabetic rats in an early stage of diabetes and the potential effect of L-arginine administration. The diabetic condition was characterized by a clear hyperglycaemic state with loose of body weight after 4 days of STZ injection. This hyperglycaemic state was associated with mitochondrial dysfunction that was evident by an impairment of the respiratory activity, increased production of superoxide anion and a clear mitochondrial depolarization. In addition, the alteration in mitochondrial physiology was associated with a significant decrease in both NO production and nitric oxide synthase type I (NOS I) expression associated to the mitochondrial membranes. An increased level of thiobarbituric acid-reactive substances (TBARS) in brain cortex homogenates from STZ-diabetic rats indicated the presence of lipid peroxidation. L-arginine treatment to diabetic rats did not change blood glucose levels but significantly ameliorated the oxidative stress evidenced by lower TBARS and a lower level of superoxide anion. This effect was paralleled by improvement of mitochondrial respiratory function and a partial mitochondrial repolarization.In addition, the administration of L-arginine to diabetic rats prevented the decrease in NO production and NOSI expression. These results could indicate that exogenously administered L-arginine may have beneficial effects on mitochondrial function, oxidative stress and NO production in brain cortex mitochondria of STZ-diabetic rats.
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Arginina/farmacología , Corteza Cerebral/efectos de los fármacos , Diabetes Mellitus Experimental/fisiopatología , Mitocondrias/efectos de los fármacos , Animales , Glucemia/metabolismo , Western Blotting , Peso Corporal , Corteza Cerebral/metabolismo , Corteza Cerebral/fisiopatología , Peroxidación de Lípido/efectos de los fármacos , Masculino , Mitocondrias/metabolismo , Mitocondrias/fisiología , Óxido Nítrico/biosíntesis , Óxido Nítrico/metabolismo , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , EstreptozocinaRESUMEN
OBJECTIVE: To determine the effects of combined aerobic and resistance exercise training during the second half of pregnancy on endothelial NOS expression (eNOS), nitric oxide (NO) production and oxygen metabolism in human placenta. METHODS: The study included 20 nulliparous in gestational week 16-20, attending prenatal care at three tertiary hospitals in Colombia who were randomly assigned into one of two groups: The exercise group (n = 10) took part in an exercise session three times a week for 12 weeks which consisted of: aerobic exercise at an intensity of 55-75% of their maximum heart rate for 60 min and 25 mins. Resistance exercise included 5 exercise groups circuit training (50 repetitions of each) using barbells (1-3 kg/exercise) and low-to-medium resistance bands. The control group (n = 10) undertook their usual physical activity. Mitochondrial and cytosol fractions were isolated from human placental tissue by differential centrifugation. A spectrophotometric assay was used to measure NO production in cytosolic samples from placental tissue and Western Blot technique to determine eNOS expression. Mitochondrial superoxide levels and hydrogen peroxide were measured to determine oxygen metabolism. RESULTS: Combined aerobic and resistance exercise training during pregnancy leads to a 2-fold increase in eNOS expression and 4-fold increase in NO production in placental cytosol (p = 0.05). Mitochondrial superoxide levels and hydrogen peroxide production rate were decreased by 8% and 37% respectively in the placental mitochondria of exercising women (p = 0.05). CONCLUSION: Regular exercise training during the second half of pregnancy increases eNOS expression and NO production and decreases reactive oxygen species generation in human placenta. Collectively, these data demonstrate that chronic exercise increases eNOS/NO production, presumably by increasing endothelial shear stress. This adaptation may contribute to the beneficial effects of exercise on the vascular and antioxidant system and in turn reduce the risk of preeclampsia, diabetes or hypertension during pregnancy.
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Ejercicio Físico/fisiología , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico/biosíntesis , Oxígeno/metabolismo , Placenta/metabolismo , Adolescente , Femenino , Expresión Génica , Humanos , Peróxido de Hidrógeno/metabolismo , Mitocondrias/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Placenta/química , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Superóxidos/metabolismo , Adulto JovenRESUMEN
Ethanol has been known to affect various behavioral parameters in experimental animals, even several hours after ethanol (EtOH) is absent from blood circulation, in the period known as hangover. The aim of this study was to assess the effects of acute ethanol hangover on motor performance in association with the brain cortex energetic metabolism. Evaluation of motor performance and brain cortex mitochondrial function during alcohol hangover was performed in mice 6 hours after a high ethanol dose (hangover onset). Animals were injected i.p. either with saline (control group) or with ethanol (3.8 g/kg BW) (hangover group). Ethanol hangover group showed a bad motor performance compared with control animals (p < .05). Oxygen uptake in brain cortex mitochondria from hangover animals showed a 34% decrease in the respiratory control rate as compared with the control group. Mitochondrial complex activities were decreased being the complex I-III the less affected by the hangover condition; complex II-III was markedly decreased by ethanol hangover showing 50% less activity than controls. Complex IV was 42% decreased as compared with control animals. Hydrogen peroxide production was 51% increased in brain cortex mitochondria from the hangover group, as compared with the control animals. Quantification of the mitochondrial transmembrane potential indicated that ethanol injected animals presented 17% less ability to maintain the polarized condition as compared with controls. These results indicate that a clear decrease in proton motive force occurs in brain cortex mitochondria during hangover conditions. We can conclude that a decreased motor performance observed in the hangover group of animals could be associated with brain cortex mitochondrial dysfunction and the resulting impairment of its energetic metabolism.
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Intoxicación Alcohólica/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Actividad Motora/efectos de los fármacos , Animales , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Corteza Cerebral/ultraestructura , Proteínas del Complejo de Cadena de Transporte de Electrón/metabolismo , Metabolismo Energético/efectos de los fármacos , Etanol/farmacología , Peróxido de Hidrógeno/metabolismo , Masculino , Ratones , Consumo de Oxígeno/efectos de los fármacosRESUMEN
The effects of cannabinoids in mitochondria after acute oxidative stress insult are not fully established. We investigated the ability of CP55,940 and JWH-015 to scavenge reactive oxygen species and their effect on mitochondria permeability transition (MPT) in either a mitochondria-free superoxide anion generation system, intact rat brain mitochondria or in sub-mitochondrial particles (SMP) treated with paraquat (PQ). Oxygen consumption, mitochondrial membrane potential (Deltapsi(m)) and MPT were determined as parameters of mitochondrial function. It is found that both cannabinoids effectively attenuate mitochondrial damage against PQ-induced oxidative stress by scavenging anion superoxide radical (O(2)(*-)) and hydrogen peroxide (H(2)O(2)), maintaining Deltapsi(m) and by avoiding Ca(2+)-induced mitochondrial swelling. Understanding the mechanistic action of cannabinoids on mitochondria might provide new insights into more effective therapeutic approaches for oxidative stress related disorders.
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Cannabinoides/farmacología , Ciclohexanoles/farmacología , Indoles/farmacología , Mitocondrias/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Paraquat/farmacología , Analgésicos/química , Analgésicos/farmacología , Animales , Calcio/metabolismo , Cannabinoides/química , Corteza Cerebral/citología , Ciclohexanoles/química , Herbicidas/farmacología , Peróxido de Hidrógeno/metabolismo , Indoles/química , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Estructura Molecular , Fármacos Neuroprotectores/química , Oxidantes/metabolismo , Ratas , Superóxidos/metabolismoRESUMEN
Dopamine is a neurotransmitter that has been related to mitochondrial dysfunction. In this study, striatal intact mitochondria and submitochondrial membranes were incubated with different dopamine concentrations, and changes on mitochondrial function, hydrogen peroxide, and nitric oxide production were evaluated. A 35% decrease in state 3 oxygen uptake (active respiration state) was found after 1 mM dopamine incubation. In addition, mitochondrial respiratory control significantly decreased, indicating mitochondrial dysfunction. High dopamine concentrations induced mitochondrial depolarization. Also, evaluation of hydrogen peroxide production by intact striatal mitochondria showed a significant increase after 0.5 and 1 mM dopamine incubation. Incubation with 0.5 and 1 mM dopamine increased nitric oxide production in submitochondrial membranes by 28 and 49%, respectively, as compared with control values. This study provides evidence that high dopamine concentrations induce striatal mitochondrial dysfunction through a decrease in mitochondrial respiratory control and loss of membrane potential, probably mediated by free radical production.
Asunto(s)
Cuerpo Estriado , Dopamina/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Animales , Células Cultivadas , Cuerpo Estriado/ultraestructura , Femenino , Radicales Libres , Peróxido de Hidrógeno/farmacología , Óxido Nítrico/farmacología , Ratas , Ratas Sprague-DawleyRESUMEN
Age related changes in brain cortex NO metabolism were investigated in mitochondria and cytosolic extracts from youth to adulthood. Decreases of 19%, 40% and 71% in NO production were observed in mitochondrial fractions from 3, 7, and 14 months old rats, respectively, as compared with 1-month-old rats. Decreased nNOS protein expression in 14 months old rats was also observed in mitochondria as compared with the nNOS protein expression in 1-month-old rats. Low levels of eNOS protein expression close to the detection limits and no iNOS protein expression were significantly detected in mitochondrial fraction for both groups of age. NO production in the cytosolic extracts also showed a marked decreasing tendency, showing higher levels than those observed in mitochondrial fractions for all groups of age. In the cytosolic extracts, however, the levels were stabilized in adult animals from 7 to 14 months. nNOS protein expression showed a similar age-pattern in cytosolic extracts for both groups of age, while the protein expression pattern for eNOS was higher expressed in adult rats (14 months) than in young animals. As well as in mitochondrial extracts iNOS protein expression was not significantly detected in cytosolic extracts at any age. RT-PCR assays indicated increased levels of nNOS mRNA in 1-month-old rats as compared with 14 months old rats, showing a similar pattern to that one observed for protein nNOS expression. A different aged pattern was observed for eNOS mRNA expression, being lower in 1-month-old rats as compared with 14 months old animals. iNOS mRNA was very low expressed in both groups of age, showing a residual iNOS mRNA that was not significantly detected. State 3 respiration rates were 78% and 85% higher when succinate and malate-glutamate were used as substrates, respectively, in 14 months rats as compared with 1-month-old rats. No changes were observed in state 4 respiration rates. These results could indicate 1 that nNOS and eNOS mRNA and protein expression can be age-dependent, and confirmed the nNOS origin for the mitochondrial NOS. During rat growth, the respiratory function seems to be modulated by NO produced by the different NOS enzymes: nNOS, eNOS and mtNOS present in the cytosol and in the mitochondria.
Asunto(s)
Envejecimiento/metabolismo , Corteza Cerebral/crecimiento & desarrollo , Corteza Cerebral/metabolismo , Mitocondrias/metabolismo , Óxido Nítrico Sintasa/metabolismo , Consumo de Oxígeno/fisiología , Animales , Citosol/metabolismo , Femenino , Luminiscencia , Óxido Nítrico Sintasa de Tipo I , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Polarografía , ARN Mensajero/biosíntesis , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Dopamine and nitric oxide systems can interact in different processes in the central nervous system. Dopamine and oxidation products have been related to mitochondrial dysfunction. In the present study, intact mitochondria and submitochondrial membranes were incubated with different DA concentrations for 5 min. Dopamine (1 mM) increased nitric oxide production in submitochondrial membranes and this effect was partially prevented in the presence of both DA and NOS inhibitor N(omega)-nitro-L-arginine (L-NNA). A 46% decrease in state 3 oxygen uptake (active respiration state) was found after 15 mM dopamine incubation. When mitochondria were incubated with 15 mM dopamine in the presence of L-NNA, state 3 respiratory rate was decreased by only 17% showing the involvement of NO. As shown for O(2) consumption, the inhibition of cytochrome oxidase by 1 mM DA was mediated by NO. Hydrogen peroxide production significantly increased after 15 mM DA incubation, being mainly due to its metabolism by MAO. Also, DA-induced depolarization was prevented by the addition of L-NNA showing the involvement of nitric oxide in this process too. This work provides evidence that in the studied conditions, dopamine modifies mitochondrial function by a nitric oxide-dependent pathway.
Asunto(s)
Dopamina/metabolismo , Mitocondrias/metabolismo , Óxido Nítrico Sintasa/metabolismo , Animales , Encéfalo/metabolismo , Cardiotónicos/metabolismo , Dopamina/química , Peróxido de Hidrógeno/química , Potencial de la Membrana Mitocondrial , Potenciales de la Membrana , Ratones , Modelos Biológicos , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Oxígeno/metabolismo , Consumo de Oxígeno , Sinaptosomas/metabolismoRESUMEN
Nitric oxide is a small signaling molecule, which may act as a neurotransmitter and neuromodulator, exerting a regulatory effect on neuronal function. It can diffuse from its site of synthesis to different intra and extracellular compartments, being therefore present in the pre-synaptic, synaptic and post-synaptic spaces. Recently, a NOS located in the mitochondria (mtNOS) has been observed in different brain regions, responsible for the production of NO in these organelles and identified as nNOS. A regulatory effect of NO on mitochondrial function was described in brain mitochondria, where NO acts mainly by inhibiting cytochrome oxidase activity. Hippocampal mitochondrial dysfunction and decreased mtNOS activity and expression were reported in association with ultrastructural damage in an experimental model of hepatic encephalopathy. Enriched environment exposure preserved the aged animals from spatial cognition impairment; also environment and training modulated neuronal plasticity in pre-pubertal rats through NO-dependent mechanisms. In addition, brain cortical mitochondrial respiration and mtNOS activity and expression were analyzed as function of age. Mitochondrial NO production showed a decreasing tendency as a function of age. These results are in accordance with the protein expression analyzed by Western Blot of mitochondrial fractions which was 6.5 times higher in 1 month aged rats as compared with 14 old animals. Concomitant with these results, a clear increasing oxygen uptake tendency in state 3 respiration was observed, meanwhile only a slight increase was observed in state 4. All these results seems to be clearly related with the reversible and concentration-dependent attenuation of the respiratory chain by NO.