Bézaire, Véronic, Wolfgang Hofmann, John K. G. Kramer, Leslie P. Kozak, and Mary-Ellen Harper. Effects of fasting on muscle mitochondrial energetics and fatty acid metabolism in Ucp3(2/2) and wild-type mice. Am J Physiol Endocrinol Metab 281: E975–E982, 2001.—Uncoupling protein-3 (UCP3) is a mitochondrial carrier protein of as yet undefined physiological function. To elucidate characteristics o...

The lesser hedgehog tenrec (Echinops telfairi) displays reptile-like thermoregulatory behavior with markedly high variability in body temperature and metabolic rate. To understand how energy metabolism copes with this flexibility, we studied the bioenergetics of isolated liver mitochondria from cold (20°C) and warm (27°C) acclimated tenrecs. Different acclimation temperatures had no impact on m...

An increased mitochondrial proton leak occurs in aging, but the origin of such modification remains unclear. This study defined the cause of mitochondrial uncoupling in mitotic (liver) and postmitotic (heart) rat tissues during aging and its effects on energy homeostasis and free radical production. Proton leak in old heart mitochondria was dependent on uncoupling proteins' upregulation, wherea...

Mitochondrial dysfunction and oxidative stress are determinant events in the pathogenesis of nonalcoholic steatohepatitis. Silybin has shown antioxidant, anti-inflammatory, and antifibrotic effects in chronic liver disease. We aimed to study the effect of the silybin-phospholipid complex (SILIPHOS) on liver redox balance and mitochondrial function in a dietary model of nonalcoholic steatohepati...

Reductions in cellular oxygen consumption (Vo2) and reactive oxygen species (ROS) production have been proposed as mechanisms underlying the anti-aging effects of calorie restriction (CR). Mitochondria are a cell's greatest "sink" for oxygen and also its primary source of ROS. The mitochondrial proton leak pathway is responsible for 20-30% of Vo2 in resting cells. We hypothesized that CR leads ...

Rationale: Acetylcarnitine plays a pivotal role in the regulation of mitochondrial and cellular lipid trafficking. The aim present study was to investigate postprandial response an oral fat load terms changes skeletal muscle acetylcarnitine intramyocellular content (IMCL) subjects with obesity through proton magnetic resonance spectroscopy (1H-MRS), association metabolism.

In pancreatic β-cells, mitochondrial bioenergetics control glucose-stimulated insulin secretion. Mitochondrial dynamics are generally associated with quality control, maintaining the functionality of bioenergetics. By acute pharmacological inhibition of mitochondrial fission protein Drp1, we demonstrate in this study that mitochondrial fission is necessary for glucose-stimulated insulin secreti...

A biological microelectromechanical system (BioMEMS) device was designed to study complementary mitochondrial parameters important in mitochondrial dysfunction studies. Mitochondrial dysfunction has been linked to many diseases, including diabetes, obesity, heart failure and aging, as these organelles play a critical role in energy generation, cell signaling and apoptosis. The synthesis of ATP ...

The cytochrome bc complexes represent a phylogenetically diverse group of complexes of electron-transferring membrane proteins, most familiarly represented by the mitochondrial and bacterial bc1 complexes and the chloroplast and cyanobacterial b6f complex. All these complexes couple electron transfer to proton translocation across a closed lipid bilayer membrane, conserving the free energy rele...

The proapoptotic mammalian protein Bax associates with mitochondrial membranes and confers a lethal phenotype when expressed in yeast. By generating Bax-resistant mutant yeast and using classical complementation cloning methods, subunits of the mitochondrial F0F1-ATPase proton pump were determined to be critical for Bax-mediated killing in S. cerevisiae. A pharmacological inhibitor of the proto...