scholarly journals Skeletal muscle metabolism in sea-acclimatized king penguins. II. Improved efficiency of mitochondrial bioenergetics

2020 ◽  
Vol 223 (21) ◽  
pp. jeb233684
Author(s):  
Damien Roussel ◽  
Vincent Marmillot ◽  
Pierre-Axel Monternier ◽  
Aurore Bourguignon ◽  
Gaëlle Toullec ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Respiratory Chain ◽  
Citrate Synthase ◽  
Coupling Efficiency ◽  
Chain Complex ◽  
Atp Synthesis ◽  
Respiratory Chain Complexes ◽  
Marine Habitat ◽  
Muscle Mitochondria

ABSTRACTAt fledging, juvenile king penguins (Aptenodytes patagonicus) must overcome the tremendous energetic constraints imposed by their marine habitat, including during sustained extensive swimming activity and deep dives in cold seawater. Both endurance swimming and skeletal muscle thermogenesis require high mitochondrial respiratory capacity while the submerged part of dive cycles repeatedly and greatly reduces oxygen availability, imposing a need for solutions to conserve oxygen. The aim of the present study was to determine in vitro whether skeletal muscle mitochondria become more ‘thermogenic’ to sustain heat production or more ‘economical’ to conserve oxygen in sea-acclimatized immature penguins (hereafter ‘immatures’) compared with terrestrial juveniles. Rates of mitochondrial oxidative phosphorylation were measured in permeabilized fibers and mitochondria from the pectoralis muscle. Mitochondrial ATP synthesis and coupling efficiency were measured in isolated muscle mitochondria. The mitochondrial activities of respiratory chain complexes and citrate synthase were also assessed. The results showed that respiration, ATP synthesis and respiratory chain complex activities in pectoralis muscles were increased by sea acclimatization. Furthermore, muscle mitochondria were on average 30–45% more energy efficient in sea-acclimatized immatures than in pre-fledging juveniles, depending on the respiratory substrate used (pyruvate, palmitoylcarnitine). Hence sea acclimatization favors the development of economical management of oxygen, decreasing the oxygen needed to produce a given amount of ATP. This mitochondrial phenotype may improve dive performance during the early marine life of king penguins, by extending their aerobic dive limit.

scholarly journals Evaluation of theIn VivoandIn VitroEffects of Fructose on Respiratory Chain Complexes in Tissues of Young Rats

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Ernesto António Macongonde ◽  
Thais Ceresér Vilela ◽  
Giselli Scaini ◽  
Cinara Ludvig Gonçalves ◽  
Bruna Klippel Ferreira ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Cerebral Cortex ◽  
Respiratory Chain ◽  
Biological Fluids ◽  
Control Group ◽  
Respiratory Chain Complexes ◽  
Mitochondrial Energy Metabolism ◽  
Chain Complexes ◽  
Aldolase B

Hereditary fructose intolerance (HFI) is an autosomal-recessive disorder characterized by fructose and fructose-1-phosphate accumulation in tissues and biological fluids of patients. This disease results from a deficiency of aldolase B, which metabolizes fructose in the liver, kidney, and small intestine. We here investigated the effect of acute fructose administration on the activities of mitochondrial respiratory chain complexes, succinate dehydrogenase (SDH), and malate dehydrogenase (MDH) in cerebral cortex, liver, kidney, and skeletal muscle of male 30-day-old Wistar rats. The rats received subcutaneous injection of sodium chloride (0.9%; control group) or fructose solution (5 μmol/g; treated group). One hour later, the animals were euthanized and the cerebral cortex, liver, kidney, and skeletal muscle were isolated and homogenized for the investigations. Acute fructose administration increased complex I-III activity in liver. On the other hand, decreased complexes II and II-III activities in skeletal muscle and MDH in kidney were found. Interestingly, none of these parameters were affectedin vitro. Our present data indicate that fructose administration elicits impairment of mitochondrial energy metabolism, which may contribute to the pathogenesis of the HFI patients.

Ultrastructural and functional abnormalities of mitochondria in cultivated fibroblasts from α-mannosidosis patients

Biologia ◽  
2009 ◽  
Vol 64 (2) ◽  
Author(s):  
Olga Brantova ◽  
Befekadu Asfaw ◽  
Jana Sladkova ◽  
Helena Poupetova ◽  
Jan Zivny ◽  
...  
Keyword(s):  
Respiratory Chain ◽  
Energy Demand ◽  
Citrate Synthase ◽  
Chain Complex ◽  
Lysosomal Storage ◽  
Respiratory Chain Complexes ◽  
Gene Encoding ◽  
Chain Complexes ◽  
Ultrastructure And Function ◽  
And Function

Abstractα-Mannosidosis is a lysosomal storage disorder caused by α-mannosidase deficiency. Clinical course of the disease ranges from severe infantile to milder juvenile type and includes mental retardation, skeletal deformities, coarse facies, hepatomegaly and hearing loss. The aim of the study was to analyse mitochondrial ultrastructure and function in cultivated fibroblasts from three patients with α-mannosidosis. All patients were homozygous for the c.2248C>T mutation in the MAN2B1 gene encoding lysosomal α-mannosidase. The mutation results in incorrect protein folding and severe decrease of α-mannosidase activity. The misfolded protein is retained by the control system of endoplasmic reticulum (ER). In analysed fibroblasts, we observed dilated ER, higher amount of aberrant mitochondria and reduced mitochondrial mass compared to controls. Respiratory chain complex IV, cytochrome c oxidase (COX), activity and the ratio between COX and citrate synthase (control enzyme) were significantly increased in comparison to controls (P < 0.05). Furthermore, the activity at least from one of other respiratory chain complexes was increased in each studied cell line. Mitochondrial membrane potential as well as reactive oxygen species production were comparable with controls. Based on our results, we hypothesize more profound effect of swelled and damaged mitochondria and ER dilatation on tissues with higher energy demand than fibroblasts have.

Proton leak induced by reactive oxygen species produced during in vitro anoxia/reoxygenation in rat skeletal muscle mitochondria

2006 ◽  
Vol 38 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Rachel Navet ◽  
Ange Mouithys-Mickalad ◽  
Pierre Douette ◽  
Claudine M. Sluse-Goffart ◽  
Wieslawa Jarmuszkiewicz ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Skeletal Muscle ◽  
Reactive Oxygen ◽  
Proton Leak ◽  
Oxygen Species ◽  
Rat Skeletal Muscle ◽  
Muscle Mitochondria ◽  
Skeletal Muscle Mitochondria

T3 increases mitochondrial ATP production in oxidative muscle despite increased expression of UCP2 and -3

2001 ◽  
Vol 280 (5) ◽  
pp. E761-E769 ◽  
Author(s):  
Kevin R. Short ◽  
Jonas Nygren ◽  
Rocco Barazzoni ◽  
James Levine ◽  
K. Sreekumaran Nair
Keyword(s):  
Skeletal Muscle ◽  
Citrate Synthase ◽  
Atp Synthesis ◽  
Nutrient Flux ◽  
Oxidative Enzymes ◽  
Mrna Levels ◽  
Plantaris Muscle ◽  
Atp Production ◽  
Protein Levels ◽  
Different Types

Triiodothyronine (T3) increases O2 and nutrient flux through mitochondria (Mito) of many tissues, but it is unclear whether ATP synthesis is increased, particularly in different types of skeletal muscle, because variable changes in uncoupling proteins (UCP) and enzymes have been reported. Thus Mito ATP production was measured in oxidative and glycolytic muscles, as well as in liver and heart, in rats administered T3 for 14 days. Relative to saline-treated controls, T3 rats had 80, 168, and 62% higher ATP production in soleus muscle, liver, and heart, respectively, as well as higher activities of citrate synthase (CS; 63, 90, 25%) and cytochrome c oxidase (COX; 119, 225, 52%) in the same tissues (all P < 0.01). In plantaris muscle of T3 rats, CS was only slightly higher (17%, P < 0.05) than in controls, and ATP production and COX were unaffected. mRNA levels of COX I and III were 33 and 47% higher in soleus of T3 rats ( P < 0.01), but there were no differences in plantaris. In contrast, UCP2 and -3 mRNAs were 2.5- to 14-fold higher, and protein levels were 3- to 10-fold higher in both plantaris and soleus of the T3 group. We conclude that T3 increases oxidative enzymes and Mito ATP production and Mito-encoded transcripts in oxidative but not glycolytic rodent tissues. Despite large increases in UCP expression, ATP production was enhanced in oxidative tissues and maintained in glycolytic muscle of hyperthyroid rats.

Relationships between the activity of respiratory-chain complexes in pre- (biopsy) or post-slaughter muscle samples and feed efficiency in random-bred Ghezel lambs

2017 ◽  
Vol 57 (8) ◽  
pp. 1674
Author(s):  
M. J. Zamiri ◽  
R. Mehrabi ◽  
G. R. Kavoosi ◽  
H. Rajaei Sharifabadi
Keyword(s):  
Respiratory Chain ◽  
Feed Intake ◽  
Enzyme Activities ◽  
Feed Efficiency ◽  
Average Daily Gain ◽  
Chain Complex ◽  
Respiratory Chain Complex ◽  
Respiratory Chain Complexes ◽  
Chain Complexes ◽  
Daily Gain

The present study was conducted to determine the relationship between the activity of mitochondrial respiratory chain complexes in pre- and post-slaughter muscle samples and residual feed intake (RFI) in Ghezel male lambs born as a result of random mating. The study was based on the hypothesis that random-bred lambs with lower feed (or higher) RFI have lower (or higher) respiratory chain-complex activity in muscle samples. Lambs (n = 30) were fed a diet consisting of 70% concentrate and 30% alfalfa hay during a 70-day period. Individual feed intake and average daily gain were recorded to calculate the RFI, feed-conversion ratio (FCR) and adjusted FCR (aFCR). On the basis of these calculations, the lambs were classified into low and high groups for RFI, with FCR and aFCR (n = 22) being one standard deviation above or below the means; this was corroborated by Student’s t-test (P &lt; 0.01). At the end of the experiment, a 10-g biopsy sample was taken from the posterior side of the left femoral biceps. After 24 h, the lambs were slaughtered, and a sample from the posterior side of the right femoral biceps was dissected for determination of mitochondrial protein and respiratory chain-complex activities (Complexes I–V). The RFI was not correlated with the metabolic bodyweight and average daily gain, but was positively correlated (r = 0.56) with the average daily feed intake (P &lt; 0.01); mean daily feed intake in the low-RFI group was 200 g less than that in the high-RFI group. The FCR and aFCR were not significantly (P &gt; 0.05) correlated with average daily feed intake (r = 0.39 and r = 0.36 respectively), but showed a negative correlation (P &lt; 0.01) with average daily gain (r = –0.73 and r = –0.76 respectively). Although very high negative correlations were recorded between the activities of all five respiratory-chain complexes and RFI in muscle samples obtained before (–0.91 to –0.97) and after (–0.92 to –0.97) slaughter, Complexes I and V showed small negative correlations (–0.40) with FCR or aFCR (P &lt; 0.05). Enzyme activities of the respiratory-chain Complexes I, III and V were not significantly different between the pre- and post-slaughter biopsy samples; however, the enzyme activities of respiratory-chain Complexes II and IV were slightly higher in post-slaughter samples (P &lt; 0.01). These results suggested that it may be possible to use the enzymatic activity of respiratory-chain complexes in muscle biopsy samples for screening of lambs for RFI, providing a useful procedure for genetic selection of lambs for this component of feed efficiency. These encouraging results need to be verified in further experiments using other sheep breeds and a larger number of lambs.

scholarly journals Comparative analysis of the bioenergetics of human adenocarcinoma Caco-2 cell line and postoperative tissue samples from colorectal cancer patients

2018 ◽  
Vol 96 (6) ◽  
pp. 808-817 ◽  
Author(s):  
Lyudmila Ounpuu ◽  
Laura Truu ◽  
Igor Shevchuk ◽  
Vladimir Chekulayev ◽  
Aleksandr Klepinin ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cell Line ◽  
Respiratory Chain ◽  
Growth Conditions ◽  
Control Analysis ◽  
Respiratory Chain Complexes ◽  
Colon Tissue ◽  
Tissue Samples

The aim of this work was to explore the key bioenergetic properties for mitochondrial respiration in the widely-used Caco-2 cell line and in human colorectal cancer (HCC) postoperational tissue samples. Oxygraphy and metabolic control analysis (MCA) were applied to estimate the function of oxidative phosphorylation in cultured Caco-2 cells and HCC tissue samples. The mitochondria of Caco-2 cells and HCC tissues displayed larger functional activity of respiratory complex (C)II compared with CI, whereas in normal colon tissue an inverse pattern in the ratio of CI to CII activity was observed. MCA showed that the respiration in Caco-2 and HCC tissue cells is regulated by different parts of electron transport chain. In HCC tissues, this control is performed essentially at the level of respiratory chain complexes I–IV, whereas in Caco-2 cells at the level of CIV (cytochrome c oxidase) and the ATP synthasome. The differences we found in the regulation of respiratory chain activity and glycose index could represent an adaptive response to distinct growth conditions; this highlights the importance of proper validation of results obtained from in-vitro models before their extrapolation to the more complex in-vivo systems.

Physiological diversity of mitochondrial oxidative phosphorylation

2006 ◽  
Vol 291 (6) ◽  
pp. C1172-C1182 ◽  
Author(s):  
G. Benard ◽  
B. Faustin ◽  
E. Passerieux ◽  
A. Galinier ◽  
C. Rocher ◽  
...  
Keyword(s):  
Oxidative Phosphorylation ◽  
Respiratory Chain ◽  
Citrate Synthase ◽  
Intrinsic Activity ◽  
Mitochondrial Oxidative Phosphorylation ◽  
Respiratory Chain Complexes ◽  
Mitochondrial Content ◽  
Physiological Diversity ◽  
Chain Complexes ◽  
Functional Features

To investigate the physiological diversity in the regulation and control of mitochondrial oxidative phosphorylation, we determined the composition and functional features of the respiratory chain in muscle, heart, liver, kidney, and brain. First, we observed important variations in mitochondrial content and infrastructure via electron micrographs of the different tissue sections. Analyses of respiratory chain enzyme content by Western blot also showed large differences between tissues, in good correlation with the expression level of mitochondrial transcription factor A and the activity of citrate synthase. On the isolated mitochondria, we observed a conserved molar ratio between the respiratory chain complexes and a variable stoichiometry for coenzyme Q and cytochrome c, with typical values of [1–1.5]:[30–135]:[3]:[9–35]:[6.5–7.5] for complex II:coenzyme Q:complex III:cytochrome c:complex IV in the different tissues. The functional analysis revealed important differences in maximal velocities of respiratory chain complexes, with higher values in heart. However, calculation of the catalytic constants showed that brain contained the more active enzyme complexes. Hence, our study demonstrates that, in tissues, oxidative phosphorylation capacity is highly variable and diverse, as determined by different combinations of 1) the mitochondrial content, 2) the amount of respiratory chain complexes, and 3) their intrinsic activity. In all tissues, there was a large excess of enzyme capacity and intermediate substrate concentration, compared with what is required for state 3 respiration. To conclude, we submitted our data to a principal component analysis that revealed three groups of tissues: muscle and heart, brain, and liver and kidney.

Sign in / Sign up

Export Citation Format

Share Document