Peroxisomal support of mitochondrial respiratory efficiency promotes ER stress survival

Endoplasmic reticulum stress (ERS) occurs when cellular demand for protein folding exceeds the capacity of the organelle. Adaptation and cell survival in response to ERS requires a critical contribution by mitochondria and peroxisomes. During ERS response, mitochondrial respiration increases to ameliorate reactive oxygen species (ROS) accumulation; we now show in yeast that peroxisome abundance also increases to promote an adaptive response. In pox1▵ cells, defective in peroxisomal ß oxidation of fatty acids, respiratory response to ERS is impaired, and ROS accrues. However, respiratory response to ERS is rescued, and ROS production is mitigated in pox1▵ cells by overexpression of Mpc1, the mitochondrial pyruvate carrier that provides another source of acetyl CoA to fuel the TCA cycle and oxidative phosphorylation. Using proteomics, select mitochondrial proteins were identified that undergo upregulation by ERS to remodel respiratory machinery. Several peroxisome-based proteins were also increased, corroborating the peroxisomal role in ERS adaptation. Finally, ERS stimulates assembly of respiratory complexes into higher order supercomplexes, underlying increased electron transfer efficiency. Our results highlight peroxisomal and mitochondrial support for ERS adaptation to favor cell survival.

The Stand For Fin Drives Energy Testing

The development of recreational diving and the new biomimetic vehicles for civilian and military purposes indicates that fins drives’ effectiveness should be a standard research procedure. The different sizes, construction and technical solutions of fin thrusters are the reason that no standard has been introduced for evaluating their efficiency. The paper presents an episode of the research carried out as part of a project financed by The National Centre for Research and Development in Poland concerning fin drives development. The first chapter presents a literature analysis of currently used research methods. A different approach to assessing efficiency was indicated, ranging from the study of the diver’s respiratory efficiency to the manipulator measurement methods. The hydrodynamic parameters, which analyzed the propellers, including fins, and the fish swimming motility characteristics, were indicated. The next chapter presents the water tunnel for basic research with measuring equipment and the range of applications. The methodology for assessing the hydrodynamic and energy efficiency of fin’s drives is presented in the third chapter. The fins’ kinematics and dynamics analysis indicated an initial set of geometric, kinematic, and dynamic parameters for energy and functional assessment purposes. The scope of available tests covered issues complex to quantify unambiguously; hence the obtained results were initial. The form made this assessment of successive pool tests, the aim of which was to analyze the kinematics of the fin’s operation. The trials of a representative fins thruster and the comments indicate the test stand’s practical use for testing various propellers.

Heat Treatment Improves Hepatic Mitochondrial Respiratory Efficiency via Mitochondrial Remodeling

Nonacholic fatty liver disease, or hepatic steatosis, is the most common liver disorder affecting the western world and currently has no pharmacologic cure. Thus, many investigations have focused on alternative strategies to treat or prevent hepatic steatosis. Our laboratory has shown that chronic heat treatment (HT) mitigates glucose intolerance, insulin resistance, and hepatic steatosis in rodent models of obesity. Here, we investigate the direct bioenergetic mechanism(s) surrounding the metabolic effects of HT on hepatic mitochondria. Utilizing mitochondrial proteomics and respiratory function assays, we show that one bout of acute HT (42°C for 20 min) in male C57Bl/6J mice (n = 6/group) triggers a hepatic mitochondrial heat shock response resulting in acute reductions in respiratory capacity, degradation of key mitochondrial enzymes, and induction of mitophagy via mitochondrial ubiquitination. We also show that chronic bouts of HT and recurrent activation of the heat shock response enhances mitochondrial quality and respiratory function via compensatory adaptations in mitochondrial organization, gene expression, and transport even during 4 weeks of high-fat feeding (n = 6/group). Finally, utilizing a liver-specific heat shock protein 72 (HSP72) knockout model, we are the first to show that HSP72, a protein putatively driving the HT metabolic response, does not play a significant role in the hepatic mitochondrial adaptation to acute or chronic HT. However, HSP72 is required for the reductions in blood glucose observed with chronic HT. Our data are the first to suggest that chronic HT (1) improves hepatic mitochondrial respiratory efficiency via mitochondrial remodeling and (2) reduces blood glucose in a hepatic HSP72-dependent manner.

Pranayama improves cardio-respiratory efficiency and physical endurance in young healthy volunteers

Background: Pranayama involves manipulation of the breath, which is a dynamic bridge between body and mind. The aim of the study was to compare cardio respiratory parameters before and after pranayama practice and to correlate the changes in physical endurance with the changes in cardio-respiratory parameters.Methods: A quasi experimental study was conducted among 120 healthy students in the age group 18-25 years. These students were given pranayama practice for 30 minutes a day for 3 days in a week for 12 weeks. The subjects were assessed for various cardio-respiratory parameters like respiratory rate (RR), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC, peak expiratory flow rate (PEFR) , breath holding time (BHT), Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), hand grip and rate of oxygen uptake per minute (VO2max) before and after pranayama practice. Statistical analysis included descriptive statistics, paired t test and Pearson correlation.Results: There was a significant decrease in RR, HR, SBP and DBP after pranayama practice. BHT, FVC, FEV1, PEFR, hand grip and vo2 max were significantly increased after pranayama practice. Physical endurance is positively correlated with hand grip and heart rate.Conclusions: The results emphasis the health benefits of pranayama. Regular pranayama improves the cardiovascular efficiency and physical endurance. In spite of yogic training being not very vigorous, cardio-respiratory efficiency was found to increase. Pranayama practice can be advocated to improve cardio-respiratory efficiency for patients as well as healthy individuals.

Effects of Cadmium on Bioaccumulation, Bioabsorption, and Photosynthesis in Sarcodia suiae

This study investigated the changes in bioaccumulation, bioabsorption, photosynthesis rate, respiration rate, and photosynthetic pigments (phycoerythrin, phycocyanin, and allophycocyanin) of Sarcodia suiae following cadmium exposure within 24 h. The bioabsorption was significantly higher than the bioaccumulation at all cadmium levels (p < 0.05). The ratios of bioabsorption/bioaccumulation in light and dark bottles were 2.17 and 1.74, respectively, when S. suiae was exposed to 5 Cd2+ mg/L. The chlorophyll a (Chl-a) concentration, oxygen evolution rate (photosynthetic efficiency), and oxygen consumption rate (respiratory efficiency) decreased with increasing bioaccumulation and ambient cadmium levels. The levels of bioaccumulation and bioabsorption in light environments were significantly higher than those in dark environments (p < 0.05). In addition, the ratios of phycoerythrin (PE)/Chl-a, phycocyanin (PC)/Chl-a, and allophycocyanin (APC)/Chl-a were also higher in light bottles compared to dark bottles at all ambient cadmium levels. These results indicated that the photosynthesis of seaweed will increase bioaccumulation and bioabsorption in a cadmium environment.