Ketamine effect on intracellular and mitochondrial calcium mobilization

The suppressive effects of ketamine on intracellular calcium has been reported in a variety of cells although the mechanisms involved are not well understood. The aim of this work was to evaluate the ketamine effect on the mitochondrial Ca2+  accumulation and the cellular Ca  mobilization using FLUO4-AM and flow cytometry. The results showed that mitochondria from ketamine injected animals presented a lower ability to retain calcium at concentrations higher than 20 μM, as compared with controls (saline injected animals). In addition, ketamine showed a significant decreased KCl-induced intracellular calcium concentration. KCl increased calcium influx through cellular depolarization. According to the data presented herein, ketamine presents a clear inhibitory effect on cytosolic Ca2+  transport mechanisms, independently from their action on the calcium channel associated NMDA receptor.Fil: Bustamante, Jaunita. Universidad Abierta Interamericana. Facultad de Medicina. Centro de Altos Estudios en Ciencias de la Salud; ArgentinaFil: Czerniczyniec, Analia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Lores Arnaiz, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; Argentin

Alcohol hangover: impairments in behavior and bioenergetics in Central Nervous System

Alcohol hangover (AH) is defined as the temporary state after alcohol binge-like drinking, starting when EtOH is absent in plasma. Results from our laboratory have shown behavioral impairments and mitochondrial dysfunction in an experimental model of AH in mice. Our model consisted in a single i.p. injection of EtOH (3.8 g/kg BW) or saline solution in male and female mice, sacrificing the animals 6 hours after injection. Motor and affective behavior together with mitochondrial function and free radical production were evaluated in brain cortex and cerebellum during AH. Results showed that hangover animals exhibited a significant reduction in neuromuscular coordination, motor strength and locomotion together with a loss of gait stability and walking deficiencies. Moreover, an increment in anxiety-like behavior together with fear-related phenotype and depression signs were observed. In relation to bioenergetics metabolism, AH induced a reduction in oxygen uptake, inhibition of respiratory complexes, changes in mitochondrial membrane permeability, decrease in transmembrane potential, increase in O2 •- and H2O2 production and impairment in nitric oxide metabolism. All together our data suggest that the physiopathological state of AH involves behavioral impairments and mitochondrial dysfunction in mouse brain cortex and cerebellum showing the long lasting effects of acute EtOH exposure in CNS.Fil: Karadayian, Analia Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Bustamante, Juanita. Universidad Abierta Interamericana. Facultad de Medicina. Centro de Altos Estudios en Ciencias de la Salud; ArgentinaFil: Lores Arnaiz, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; Argentin

Hydrogen peroxide metabolism during peroxisome proliferation by fenofibrate

AbstractFenofibrate, the hypolipidemic drug and peroxisome proliferator, was given to mice (0.23% w/w in the diet) during 1–3 weeks and enzyme activities, H2O2 concentration, and H2O2 production rate were determined. A maximal increase of 150% in liver/body weight ratio was observed after 3 weeks of treatment. Acyl-CoA oxidase, catalase and uricase activities were increased by 712%, 506% and 41% respectively by treatment with fenofibrate. Se- and non Se-glutathione peroxidase and Mn-superoxide dismutase activities were increased by 331 %, 188% and 130% respectively in the liver of 2 weeks-treated mice. CuZn superoxide dismutase activity was not affected by fenofibrate treatment. H2O2 steady-state concentration showed an increase of 89% after 2 weeks of treatment. H2O2 production rates, and the steady-state concentrations of the intermediates HO , R and ROO , calculated using experimental data, were higher in the liver of fenofibrate-treated mice than in control animals. According to our findings, the imbalance between H2O2 production and its degradation by its metabolizing enzymes during peroxisome proliferation, would result in an increased level of H2O2 steady-state concentration, with the resulting oxidative stress which may lead to the generation of oxidative damage and to the induction of liver carcinogenesis

Alterations of motor performance and brain cortex mitochondrial function during ethanol hangover

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 IVwas 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.Fil: Bustamante, Juanita. Universidad de Buenos Aires; ArgentinaFil: Karadayian, Analia Graciela. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Lores Arnaiz, Silvia. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Cutrera, Rodolfo Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas; Argentin

Effect of Exercise Training on eNnos Expression, NO Production and Oxygen Metabolism in Human Placenta.

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.Fil: Ramírez-Vélez, Robinson.Fil: Bustamante, Juanit.Fil: Czerniczyniec, Analia. Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Bioquimica y Medicina Molecular;Fil: Aguilar de Plata, Ana.Fil: Lores Arnaiz, Silvia. Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Bioquimica y Medicina Molecular

Effect of Exercise Training on eNnos Expression, NO Production and Oxygen Metabolism in Human Placenta.

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.Fil: Ramírez-Vélez, Robinson.Fil: Bustamante, Juanit.Fil: Czerniczyniec, Analia. Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Bioquimica y Medicina Molecular;Fil: Aguilar de Plata, Ana.Fil: Lores Arnaiz, Silvia. Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Bioquimica y Medicina Molecular

Reactions of peroxynitrite in the mitochondrial matrix

Superoxide radical (O2 -) and nitric oxide (NO) produced at the mitochondrial inner membrane react to form peroxynitrite (ONOO-) in the mitochondrial matrix. Intramitochondrial ONOO- effectively reacts with a few biomolecules according to reaction constants and intramitochondrial concentrations. The second-order reaction constants (in M-1 s-1) of ONOO- with NADH (233 ± 27), ubiquinol-0 (485 ± 54) and GSH (183 ± 12) were determined fluorometrically by a simple competition assay of product formation. The oxidation of the components of the mitochondrial matrix by ONOO- was also followed in the presence of CO2, to assess the reactivity of the nitrosoperoxocarboxylate adduct (ONOOCO2 -) towards the same reductants. The ratio of product formation was about similar both in the presence of 2.5 mM CO2 and in air-equilibrated conditions. Liver submitochondrial particles supplemented with 0.25-2 μM ONOO- showed a O2 - production that indicated ubisemiquinone formation and autooxidation. The nitration of mitochondrial proteins produced after addition of 200 μM ONOO- was observed by Western blot analysis. Protein nitration was prevented by the addition of 50-200 μM ubiquinol-0 or GSH. An intramitochondrial steady state concentration of about 2 nM ONOO- was calculated, taking into account the rate constants and concentrations of ONOO- coreactants. (C) 2000 Elsevier Science Inc.Fil: Valdez, Laura Batriz. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Alvarez, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; ArgentinaFil: Lores Arnaiz, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; ArgentinaFil: Schöpfer, Francisco. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín. Laboratorio de Metabolismo del Oxígeno; ArgentinaFil: Carreras, Maria Cecilia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín. Laboratorio de Metabolismo del Oxígeno; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Poderoso, Juan José. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín. Laboratorio de Metabolismo del Oxígeno; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Boveris, Alberto Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentin

Acute hypobaric hypoxia and cardiac energetic response in prepubertal rats: role of nitric oxide

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.Fil: la Padula, Pablo Hugo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto Alberto C. Taquini de Investigaciones En Medicina Traslacional. - Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiologicas "prof. Dr. Alberto C. Taquini". Instituto Alberto C. Taquini de Investigaciones En Medicina Traslacional.; ArgentinaFil: Czerniczyniec, Analia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Bonazzola, Patricia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto Alberto C. Taquini de Investigaciones En Medicina Traslacional. - Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiologicas "prof. Dr. Alberto C. Taquini". Instituto Alberto C. Taquini de Investigaciones En Medicina Traslacional.; ArgentinaFil: Piotrkowski, Barbara. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Vanasco, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Lores Arnaiz, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Costa, Lidia Esther. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto Alberto C. Taquini de Investigaciones En Medicina Traslacional. - Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiologicas "prof. Dr. Alberto C. Taquini". Instituto Alberto C. Taquini de Investigaciones En Medicina Traslacional.; Argentin

The COLIBAS study-COVID-19 lockdown effects on mood, academic functioning, alcohol consumption, and perceived immune fitness:data from Buenos Aires University students

A recent study was conducted in the Netherlands to evaluate the impact of the 2019 coronavirus (COVID-19) pandemic and its associated lockdown periods on academic functioning, mood, and health correlates such as alcohol consumption. The study revealed that lockdowns were associated with a significantly poorer mood and a reduced perceived immune fitness. Overall, a reduction was seen in alcohol consumption during the lockdown periods. Academic functioning in terms of performance was unaffected; however, a significant reduction in interactions with other students and teachers was reported. There was, however, great variability between students as follows: both an increase and a reduction in alcohol consumption were reported, as well as improvements and poorer academic functioning. The aim of the current online study was to replicate these findings in Argentina. To this extent, a modified version of the survey was conducted among students at the University of Buenos Aires, which was adapted to the local lockdown measures. The survey assessed possible changes in self-reported academic functioning, mood, and health correlates, such as alcohol consumption, perceived immune functioning, and sleep quality compared to before the COVID-19 pandemic. Retrospective assessments were made for four periods, including (1) the period before COVID-19, (2) the first lockdown period (March–December 2020), (3) summer 2021 (January-March 2021, no lockdown), and (4) the second lockdown (from April 2021 to July 2021). This article describes the content of the survey and the corresponding dataset. The survey was completed by 508 participants. Dataset: The dataset is submitted as a Supplementary File. Dataset License: CC0

The COLIBAS Study—COVID-19 Lockdown Effects on Mood, Academic Functioning, Alcohol Consumption, and Perceived Immune Fitness: Data from Buenos Aires University Students

A recent study was conducted in the Netherlands to evaluate the impact of the 2019 coronavirus (COVID-19) pandemic and its associated lockdown periods on academic functioning, mood, and health correlates such as alcohol consumption. The study revealed that lockdowns were associated with a significantly poorer mood and a reduced perceived immune fitness. Overall, a reduction was seen in alcohol consumption during the lockdown periods. Academic functioning in terms of performance was unaffected; however, a significant reduction in interactions with other students and teachers was reported. There was, however, great variability between students as follows: both an increase and a reduction in alcohol consumption were reported, as well as improvements and poorer academic functioning. The aim of the current online study was to replicate these findings in Argentina. To this extent, a modified version of the survey was conducted among students at the University of Buenos Aires, which was adapted to the local lockdown measures. The survey assessed possible changes in self-reported academic functioning, mood, and health correlates, such as alcohol consumption, perceived immune functioning, and sleep quality compared to before the COVID-19 pandemic. Retrospective assessments were made for four periods, including (1) the period before COVID-19, (2) the first lockdown period (March–December 2020), (3) summer 2021 (January-March 2021, no lockdown), and (4) the second lockdown (from April 2021 to July 2021). This article describes the content of the survey and the corresponding dataset. The survey was completed by 508 participants. Dataset: The dataset is submitted as a Supplementary File. Dataset License: CC0