Search results for "Skeletal muscle"

Data on in vivo PGC-1alpha overexpression model via local transfection in aged mouse muscle

2018

The data presented in this article are related to the research paper entitled “Intensified mitophagy in skeletal muscle with aging is downregulated by PGC-1alpha overexpression in vivo” (Yeo et al., 2019). The data explained the surgical procedure of in vivo local transfection by electroporation method in aged mouse tibialis anterior muscle, and plasmid DNA preparation and verification protocol. The data also showed the transfection efficiency levels of GFP or GFP-tagged PGC-1alpha through immunohistochemistry method for frozen muscle cross-sections.

2020

In midlife, women experience hormonal changes due to menopausal transition. A decrease especially in estradiol has been hypothesized to cause loss of muscle mass. This study investigated the effect of menopausal transition on changes in lean and muscle mass, from the total body to the muscle fiber level, among 47–55-year-old women. Data were used from the Estrogenic Regulation of Muscle Apoptosis (ERMA) study, where 234 women were followed from perimenopause to early postmenopause. Hormone levels (estradiol and follicle stimulating hormone), total and regional body composition (dual-energy X-ray absorptiometry (DXA) and computed tomography (CT) scans), physical activity level (self-reported…

Estrogen Regulates the Satellite Cell Compartment in Females

2018

SUMMARYSkeletal muscle mass, strength, and regenerative capacity decline with age, with many measures showing greater deterioration in females about the time estrogen levels decrease at menopause. Here we show that maintenance of muscle stem cells, satellite cells, as well as self-renewal and differentiation into muscle fibers, are severely compromised by estrogen deficiency. Mechanistically, by hormone replacement, use of a selective estrogen-receptor modulator (bazedoxifene), and conditional estrogen receptor knockout, we implicate 17β-estradiol and satellite cell expression of estrogen receptorα(ERα) and show that estrogen signaling through this receptor is necessary to prevent apoptosis…

2019

Abstract Background Physical activity and dietary intake of dairy products are associated with improved metabolic health. Dairy products are rich with branched chain amino acids that are essential for energy production. To gain insight into the mechanisms underlying the benefit of the sub-chronic effects of running and intake of milk protein supplements, we studied L ow C apacity R unner rats (LCR), a rodent exercise model with risk for metabolic disorders. We especially focused on the role of Sirtuins, energy level dependent proteins that affect many cellular metabolic processes. Methods Forty-seven adult LCR female rats sedentary or running voluntarily in wheels were fed normal chow and g…

Increased physical activity decreases hepatic free fatty acid uptake: a study in human monozygotic twins

2006

Exercise is considered to be beneficial for free fatty acid (FFA) metabolism, although reports of the effects of increased physical activity on FFA uptake and oxidation in different tissues in vivo in humans have been inconsistent. To investigate the heredity-independent effects of physical activity and fitness on FFA uptake in skeletal muscle, the myocardium, and liver we used positron emission tomography (PET) in nine healthy young male monozygotic twin pairs discordant for physical activity and fitness. The cotwins with higher physical activity constituting the more active group had a similar body mass index but less body fat and 18 +/- 10% higher (P < 0.001) compared to the less active …

Effects of fatiguing jumping exercise on mRNA expression of titin-complex proteins and calpains.

2009

Eccentric exercise induced by electrostimulation increases mRNA expression of titin-complex proteins in rodent skeletal muscle. In this study, mRNA expression of titin, muscle LIM protein (MLP), cardiac ankyrin repeat protein (CARP), ankyrin repeat domain protein 2 (Ankrd2), diabetes-related ankyrin repeat protein (DARP), and calcium-activated proteinases, calpains, were investigated in human skeletal muscle after fatiguing jumping exercise. Fatiguing jumping exercise did not change mRNA expression of titin, DARP, calpain 1, or calpain 3. MLP, Ankrd2 and calpain 2 mRNA levels were increased 2 days postexercise. CARP mRNA level was already elevated 30 min and remained elevated 2 days postexe…

Age affects myosin relaxation states in skeletal muscle fibers of female but not male mice

2018

The recent discovery that myosin has two distinct states in relaxed muscle–disordered relaxed (DRX) and super-relaxed (SRX)–provides another factor to consider in our fundamental understanding of the aging mechanism in skeletal muscle, since myosin is thought to be a potential contributor to dynapenia (age-associated loss of muscle strength independent of atrophy). The primary goal of this study was to determine the effects of age on DRX and SRX states and to examine their sex specificity. We have used quantitative fluorescence microscopy of the fluorescent nucleotide analog 2′/3′-O-(N-methylanthraniloyl) ATP (mantATP) to measure single-nucleotide turnover kinetics of myosin in skinned skel…

Control of adenine nucleotide metabolism and glycolysis in vertebrate skeletal muscle during exercise.

1996

The turnover of adenosine triphosphate (ATP) in vertebrate skeletal muscle can increase more than a hundredfold during high-intensity exercise, while the content of ATP in muscle may remain virtually unchanged. This requires that the rates of ATP hydrolysis and ATP synthesis are exactly balanced despite large fluctuations in reaction rates. ATP is regenerated initially at the expense of phosphocreatine (PCr) and then mainly through glycolysis from muscle glycogen. The increased ATP turnover in contracting muscle will cause an increase in the contents of adenosine diphosphate (ADP), adenosine monophosphate (AMP) and inorganic phosphate (P(i)), metabolites that are substrates and activators o…

Role of skeletal muscle-fibre type in regulation of glucose metabolism in middle-aged subjects with impaired glucose tolerance during a long-term exe…

2005

Aim: The aim of this study was to investigate the role of skeletal muscle fibre type in the regulation of glucose metabolism in middle-aged obese subjects with impaired glucose tolerance (IGT) during a 2-year exercise anddietary intervention. Methods: Muscle biopsies (musculus vastus lateralis) were taken from 22 subjects belonging to the intervention group of the Finnish Diabetes Prevention Study [1]. According to their myosin heavy chain (MHC) profile at the baseline, the subjects were divided into two groups: IGT s l o w (n = 10) with a high proportion of MHC I isoforms and IGT f a s t (n = 12) with a high proportion of MHC II isoforms in the vastus lateralis muscle. The intervention con…

Influence of training and a maximal exercise test in analytical variability of muscular, hepatic, and cardiovascular biochemical variables.

2014

Short, middle, and long-term exercise, as well as the relative intensity of the physical effort, may influence a broad array of laboratory results, and it is thereby of pivotal importance to appropriately differentiate the 'physiologic' from the 'pathological' effects of exercise. Therefore, the values of some biomarkers in physically active subjects may be cautiously interpreted since the results may fall outside the conventional reference ranges. It has been demonstrated that middle and long-term endurance and/or strenuous exercise triggers transient elevations of muscular and cardiac biomarkers. However, no data have been published about the effect of short-term maximal exercise test on …