The purpose of this study was to examine the effects of 6 weeks of localized, muscle-focused (quadriceps femoris) passive heat therapy (PHT) on resistance artery function, exercise haemodynamics and exercise performance relative to knee extension (KE) exercise training (EX). We randomized 34 healthy adults (ages 18-36; n = 17 female, 17 male) to receive either PHT or sham heating sessions (120 min, 3 days/week), or EX (40 min, 3 days/week) over 6 weeks. Blood flow was assessed with Doppler ultrasound of the femoral artery during both passive leg movement (PLM) and a KE graded exercise test.
View Article and Find Full Text PDFAcetyl-CoA synthetase short-chain family member 1 (ACSS1) uses acetate to generate mitochondrial acetyl-CoA and is regulated by deacetylation by sirtuin 3. We generated an ACSS1-acetylation (Ac) mimic mouse, where lysine-635 was mutated to glutamine (K635Q). Male mice were smaller with higher metabolic rate and blood acetate and decreased liver/serum ATP and lactate levels.
View Article and Find Full Text PDFThe mitochondria are central to skeletal muscle metabolic health. Impaired mitochondrial function is associated with various muscle pathologies, including insulin resistance and muscle atrophy. As a result, continuous efforts are made to find ways to improve mitochondrial health in the context of disuse and disease.
View Article and Find Full Text PDFAIM: Mild heat stress can improve mitochondrial respiratory capacity in skeletal muscle. However, long-term heat interventions are scarce, and the effects of heat therapy need to be understood in the context of the adaptations which follow the more complex combination of stimuli from exercise training. The purpose of this work was to compare the effects of 6 weeks of localized heat therapy on human skeletal muscle mitochondria to single-leg interval training.
View Article and Find Full Text PDFValproic acid (VPA) is an antiepileptic, bipolar, and migraine medication, which is associated with embryonic dysmorphology, more specifically neural tube defects (NTDs), if taken while pregnant. One mechanism by which VPA may cause NTDs is through oxidative stress that cause disruption of cell signaling. However, mechanisms of VPA-induced oxidative stress are not fully understood.
View Article and Find Full Text PDFThough effective in treating various types of cancer, the chemotherapeutic doxorubicin (DOX) is associated with skeletal muscle wasting and fatigue. The purpose of this study was to assess muscle function in situ following DOX administration in mice. Furthermore, pre-treatments with exercise (EX) or metformin (MET) were used in an attempt to preserve muscle function following DOX.
View Article and Find Full Text PDFPurpose: Very little research has investigated the effects of ultraendurance exercise on the bioenergetic status of muscle. The primary objective of this case study was to characterize the changes that occur in skeletal muscle mitochondria in response to a 100-km ultramarathon in monozygotic twins. A second objective was to determine whether mitochondrial function is altered by consuming a periodized low-carbohydrate, high-fat diet during training compared with a high-carbohydrate diet.
View Article and Find Full Text PDFAm J Physiol Endocrinol Metab
May 2019
Doxorubicin (DOX) is an effective chemotherapeutic treatment with lasting side effects in heart and skeletal muscle. DOX is known to bind with iron, contributing to oxidative damage resulting in cardiac and skeletal muscle toxicity. However, major cellular changes to iron regulation in response to DOX are poorly understood in liver, heart, and skeletal muscle.
View Article and Find Full Text PDF