Gaineshanley2654

Global climatic warming is predicted to drive extreme thermal events, especially in temperate terrestrial environments. Hence, describing how physiological parameters are affected by acute temperature changes would allow us to understand the energy management of organisms facing such non-predictable and constraining events. As mitochondria play a key role in the conversion of energy from food into ATP but also produce harmful reactive oxygen species, the understanding of its functioning is crucial to determine the proximal causes of potential decline in an animal's performance. Here we studied the effects of acute temperature changes (between 20 and 30°C) on mitochondrial respiration, ATP synthesis rate, oxidative phosphorylation efficiency (ATP/O), and H2O2 generation in isolated liver mitochondria of a terrestrial ectotherm, the common toad (Bufo bufo). Using succinate as the respiratory substrate, we found that the mitochondrial rates of oxygen consumption, ATP synthesis, and H2O2 generation increased as the temperature increased, being 65, 52, and 66% higher at 30°C than at 20°C, respectively. We also found that the mitochondrial coupling efficiency (ATP/O) decreased, while the oxidative cost of ATP production (H2O2/ATP ratio) increased. The present results further indicate that between 40 and 60% of temperature effects on mitochondrial ATP production and H2O2 generation was at minima driven by an action on the oxidative capacity of the mitochondria. These results suggest that B. bufo may need to allocate extra energy to maintain ATP production and protect cells from oxidative stress, reducing the energy allocable performances. Copyright © 2020 Roussel and Voituron.Background Anxiety and depression are common symptoms in patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI). The 24-form Tai Chi may exert a protective function for CHD patients after PCI by improving anxiety and depression. Methods Patients who received PCI after 1-4 days were randomly assigned to the 24-form Tai Chi group (TG) and the control group (CG). The differences in anxiety and depression, using the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36), before and after an average of 10 months of Tai Chi intervention were compared in both groups to analyze the effects of Tai Chi on the emotion and the life quality of CHD patients. learn more Meanwhile, the relative levels of miR-17-92 were measured by using real-time qPCR. The association between the relative levels of miR-17-92 and the anxiety and the depression of CHD patients after PCI was analyzed. Adjusted Cox models were used to explore the effect of Tai Chi exercise in CHD patients. Results After 10 months of intervention, the changes in the anxiety subscale (P = 0.002), in the depression subscale (P = 0.008), and in the stress (P = 0.015) scores were higher in the TG group when compared to those of the CG group. The proportion of anxious (P = 0.045) and depressed subjects (P = 0.042) in the TG group was lower than that in the CG group. On the other hand, the increase in the SF-36 scores and in the relative levels of miR-17-92 was significantly higher in the TG group when compared with that of the CG group (P less then 0.05). The serum level of miR-17-92 had a negative correlation with the anxiety, the depression, and the stress scores (P less then 0.01). Conclusion The 24-form Tai Chi improved the anxiety and the depression symptoms and upregulated the miR-17-92 levels in CHD patients after PCI. Copyright © 2020 Liu, Yu, Lv and Wang.Obesity is a worldwide epidemic disease that induces important structural and functional changes to the heart and predisposes a patient to devastating cardiac complications. Sirtuin1 (SIRT1) has been found to have roles in regulating cardiac function, but whether it can help in cardioprotection is not clear. The aim of the present study was to determine whether melatonin, by modulating SIRT1 and in turn mitochondria signaling, may alleviate obesity-induced cardiac injuries. We investigated 10 lean control mice and 10 leptin-deficient obese mice (ob/ob) orally supplemented with melatonin for 8 weeks, as well as equal numbers of age-matched lean and ob/ob mice that did not receive melatonin. Hearts were evaluated using multiple parameters, including biometric values, morphology, SIRT1 activity and expression of markers of mitochondria biogenesis, oxidative stress, and inflammation. We observed that ob/ob mice experienced significant heart hypertrophy, infiltration by inflammatory cells, reduced SIRT1 activity, altered mitochondrial signaling and oxidative balance, and overexpression of inflammatory markers. Notably, melatonin supplementation in ob/ob mice reverted these obesogenic heart alterations. Melatonin prevented heart remodeling caused by obesity through SIRT1 activation, which, together with mitochondrial pathways, reduced oxidative stress and inflammation. Copyright © 2020 Favero, Franco, Stacchiotti, Rodella and Rezzani.The determinants of cardiac output (CO) during exercise, i.e., stroke volume (SV) and heart rate (HR), could differ in Paralympic athletes (PAthl) with spinal cord injury (SCI) with respect to PAthl with locomotor impairments caused by different health conditions (HCs). The purposes of the present study were the comparisons of two groups of PAthl, one with SCI and the other with either amputation (AMP) or post poliomyelitis syndrome (PM), assessing the (1) peak cardiorespiratory responses and determinants (SV and HR) of CO during maximal and submaximal arm cranking exercise (ACE), respectively; (2) correlations between peak oxygen uptake (VO2peak) and the highest SV obtained during submaximal exercise; and (3) correlations between oxygen pulse (O2 pulse, ratio between VO2 and HR) and both SV and O2 arterio-venous difference [(a-v)O2diff]. Each athlete (19 PAthl with SCI, 9 with AMP, and 5 with PM) completed a continuous incremental cardiopulmonary ACE test to volitional fatigue to assess peak responses. In a of CO at maximal and submaximal ACE; (2) SV is a significant determinant of VO2peak, suggesting cardiac adaptations possible also in PAthl with SCI; and (3) SV can be predicted from O2 pulse measurements during submaximal exercise in both groups of PAthl. Copyright © 2020 Bernardi, Guerra, Rodio, Dante, Castellano, Peluso, Schena and Bhambhani.