scholarly journals The rate of substrate cycling between fructose 6-phosphate and fructose 1,6-bisphosphate in skeletal muscle from cold-exposed, hyperthyroid or acutely exercised rats

1985 ◽  
Vol 231 (1) ◽  
pp. 217-220 ◽  
Author(s):  
R A J Challis ◽  
J R S Arch ◽  
E A Newsholme
Keyword(s):  
Cold Exposure ◽  
Acute Exercise ◽  
Vastus Lateralis ◽  
Exercise Bout ◽  
Vastus Lateralis Muscle ◽  
Hyperthyroid State ◽  
Fructose 1,6 Bisphosphatase ◽  
Fructose 1,6 Bisphosphate

The effects of cold-exposure, the hyperthyroid state and a single exercise bout in vivo on the maximal enzyme activities of 6-phosphofructokinase and fructose-1,6-bisphosphatase in vastus lateralis muscle and the rates of fructose 6-phosphate/fructose 1,6-bisphosphate cycling measured in epitrochlearis muscle in vitro were investigated. In all cases significant changes in substrate cycling rates were observed, whether in the absence of added hormones in vitro (acute exercise), or when stimulated by insulin plus adrenaline (cold-exposure), or with respect to the catecholamine-sensitivity of the cycling rate (the hyperthyroid state).

Additive effects of cortisol and growth hormone on regional and systemic lipolysis in humans

2004 ◽  
Vol 286 (3) ◽  
pp. E488-E494 ◽  
Author(s):  
C. B. Djurhuus ◽  
C. H. Gravholt ◽  
S. Nielsen ◽  
S. B. Pedersen ◽  
N. Møller ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Adipose Tissue ◽  
Vastus Lateralis ◽  
Vastus Lateralis Muscle ◽  
Additive Effects ◽  
Subcutaneous Adipose ◽  
In Vivo Effects ◽  
Circulating Levels

Growth hormone (GH) and cortisol are important to ensure energy supplies during fasting and stress. In vitro experiments have raised the question whether GH and cortisol mutually potentiate lipolysis. In the present study, combined in vivo effects of GH and cortisol on adipose and muscle tissue were explored. Seven lean males were examined four times over 510 min. Microdialysis catheters were inserted in the vastus lateralis muscle and in the subcutaneous adipose tissue of the thigh and abdomen. A pancreatic-pituitary clamp was maintained with somatostatin infusion and replacement of GH, insulin, and glucagon at baseline levels. At t = 150 min, administration was performed of NaCl (I), a 2 μg·kg-1·min-1hydrocortisone infusion (II), a 200-μg bolus of GH (III), or a combination of II and III (IV). Systemic free fatty acid (FFA) turnover was estimated by [9,10-3H]palmitate appearance. Circulating levels of glucose, insulin, and glucagon were comparable in I-IV. GH levels were similar in I and II (0.50 ± 0.08 μg/l, mean ± SE). Peak levels during III and IV were ∼9 μg/l. Cortisol levels rose to ∼900 nmol/l in II and IV. Systemic (i.e., palmitate fluxes, s-FFA, s-glycerol) and regional (interstitial adipose tissue and skeletal muscle) markers of lipolysis increased in response to both II and III. In IV, they were higher and equal to the isolated additive effects of the two hormones. In conclusion, we find that GH and cortisol stimulate systemic and regional lipolysis independently and in an additive manner when coadministered. On the basis of previous studies, we speculate that the mode of action is mediated though different pathways.

scholarly journals Proliferation of Human Primary Myoblasts Is Associated with Altered Energy Metabolism in Dependence on AgeingIn VivoandIn Vitro

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Reedik Pääsuke ◽  
Margus Eimre ◽  
Andres Piirsoo ◽  
Nadežda Peet ◽  
Liidia Laada ◽  
...  
Keyword(s):  
Energy Metabolism ◽  
Satellite Cells ◽  
Vastus Lateralis ◽  
Enzyme Analysis ◽  
Vastus Lateralis Muscle ◽  
Low Grade ◽  
Older Individuals ◽  
Older Subjects

Background. Ageing is associated with suppressed regenerative potential of muscle precursor cells due to decrease of satellite cells and suppressive intramuscular milieu on their activation, associated with ageing-related low-grade inflammation. The aim of the study was to characterize the function of oxidative phosphorylation (OXPHOS), glycolysis, adenylate kinase (AK), and creatine kinase (CK) mediated systems in young and older individuals.Materials and Methods. Myoblasts were cultivated from biopsies taken by transcutaneous conchotomy from vastus lateralis muscle in young (20–29 yrs,n=7) and older (70–79 yrs,n=7) subjects. Energy metabolism was assessed in passages 2 to 6 by oxygraphy and enzyme analysis.Results. In myoblasts of young and older subjects the rate of OXPHOS decreased during proliferation from passages 2 to 6. The total activities of CK and AK decreased. Myoblasts of passage 2 cultivated from young muscle showed higher rate of OXPHOS and activities of CK and AK compared to myoblasts from older subjects while hexokinase and pyruvate kinase were not affected by ageing.Conclusions. Proliferation of myoblastsin vitrois associated with downregulation of OXPHOS and energy storage and transfer systems. Ageingin vivoexerts an impact on satellite cells which results in altered metabolic profile in favour of the prevalence of glycolytic pathways over mitochondrial OXPHOS of myoblasts.

scholarly journals The influence of physical training on the angiopoietin and VEGF-A systems in human skeletal muscle

2007 ◽  
Vol 103 (3) ◽  
pp. 1012-1020 ◽  
Author(s):  
T. Gustafsson ◽  
H. Rundqvist ◽  
J. Norrbom ◽  
E. Rullman ◽  
E. Jansson ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Human Skeletal Muscle ◽  
Acute Exercise ◽  
Vastus Lateralis ◽  
Exercise Bout ◽  
Voluntary Exercise ◽  
Vastus Lateralis Muscle ◽  
Mrna Levels ◽  
Ki 67

Eleven subjects performed one-legged exercise four times per week for 5 wk. The subjects exercised one leg for 45 min with restricted blood flow (R leg), followed by exercise with the other leg at the same absolute workload with unrestricted blood flow (UR leg). mRNA and protein expression were measured in biopsies from the vastus lateralis muscle obtained at rest before the training period, after 10 days, and after 5 wk of training, as well as 120 min after the first and last exercise bouts. Basal Ang-2 and Tie-1 mRNA levels increased in both legs with training. The Ang-2-to-Ang-1 ratio increased to a greater extent in the R leg. The changes in Ang-2 mRNA were followed by similar changes at the protein level. In the R leg, VEGF-A mRNA expression responded transiently after acute exercise both before and after the 5-wk training program. Over the course of the exercise program, there was a concurrent increase in basal VEGF-A protein and VEGFR-2 mRNA in the R leg. Ki-67 mRNA showed a greater increase in the R leg and the protein was localized to the endothelial cells. In summary, the increased translation of VEGF-A is suggested to be caused by the short mRNA burst induced by each exercise bout. The concurrent increase in the Ang-2-to-Ang-1 ratio and the VEGF-expression combined with the higher level of Ki-67 mRNA in the R leg indicate that changes in these systems are of importance also in nonpathological angiogenic condition such as voluntary exercise in humans. It further establish that hypoxia/ischemia-related metabolic perturbation is likely to be involved as stimuli in this process in human skeletal muscle.

Control of glycolysis in vertebrate skeletal muscle during exercise

1996 ◽  
Vol 270 (4) ◽  
pp. R821-R829 ◽  
Author(s):  
U. Krause ◽  
G. Wegener
Keyword(s):  
Gastrocnemius Muscle ◽  
Rana Temporaria ◽  
High Capacity ◽  
Repeated Exercise ◽  
Frog Rana Temporaria ◽  
Time Courses ◽  
Fructose 1,6 Bisphosphate ◽  
Assay Conditions

The gastrocnemius muscle of the frog (Rana temporaria) has a high capacity for anaerobic glycolysis from glycogen. Glycolytic metabolites and effectors of phosphofructokinase, particularly the hexose bisphosphates, were followed in muscle during exercise (swimming between 5 s and 5 min), recovery (rest for up to 2 h after 5 min of swimming), and repeated exercise (swimming for up to 60 s after 2 h of recovery). Glycogen phosphorylase and phosphofructokinase were swiftly activated with exercise. The hexose bisphosphates followed markedly different time courses. Fructose 1,6-bisphosphate was transiently increased in both exercise and repeated exercise. This appears to be an effect rather than a cause of phosphofructokinase activation. Glucose 1,6-biphosphate was accumulated only while phosphofructokinase was active and was unchanged at other times. Fructose 2,6-biphosphate showed a 10-fold transient increase on exercise in rested frogs, almost disappeared from the muscle during recovery, and did not change during repeated exercise. Fructose 2,6-biphosphate is a potent activator of phosphofructokinase in vitro under near physiological assay conditions, and it may serve this function also in vivo during exercise. Glucose 1,6-biphosphate could be an activator of phosphofructokinase in repeated exercise when fructose 2,6-biphosphate is not available.

In vitro human masseter muscle hypersensitivity: a possible explanation for increase in masseter tone

1996 ◽  
Vol 80 (5) ◽  
pp. 1547-1553 ◽  
Author(s):  
P. J. Adnet ◽  
H. Reyford ◽  
B. M. Tavernier ◽  
T. Etchrivi ◽  
I. Krivosic ◽  
...  
Keyword(s):  
Masseter Muscle ◽  
Fiber Type ◽  
Vastus Lateralis ◽  
Threshold Concentration ◽  
Vastus Lateralis Muscle ◽  
Type I ◽  
Cross Sectional ◽  
Significant Difference ◽  
Maximal Tension

To determine whether a difference in fiber-type caffeine and Ca2+ sensitivities exists between human masseter and vastus lateralis skeletal muscle, we compared the fiber-type caffeine sensitivities in chemically skinned muscle fibers from 13 masseter and 18 vastus lateralis muscles. Caffeine sensitivity was defined as the threshold concentration inducing > 10% of the maximal tension obtained after the fiber was loaded with a 1.6 x 10(-2) mM Ca2+ solution for 30 s. Significant difference in the mean caffeine sensitivity was found between type I masseter fibers [2.57 +/- 1.32 (SD) mM] vs. type I (6.02 +/- 1.74 mM) and type II vastus lateralis fibers (11.25 +/- 3.13 mM). Maximal Ca(2+)-activated force per cross-sectional area was significantly different between masseter and vastus lateralis fibers. However, the Ca2+ concentration corresponding to half-maximal tension (pCa50) was not significantly different between type I masseter (pCa50 5.9 +/- 0.02) and type I vastus lateralis muscle (pCa50 6.01 +/- 0.08). These results suggest that the increase in caffeine sensitivity of masseter muscle reflects the presence of a low reactivity threshold of the sarcoplasmic reticulum.

In vivo and in vitro lipogenesis and aspects of metabolism in ovines: Effect of environmental temperature and dietary lipid supplementation

2000 ◽  
Vol 80 (1) ◽  
pp. 59-67 ◽  
Author(s):  
J. A. Moibi ◽  
R. J. Christopherson ◽  
E. K. Okine
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Cold Exposure ◽  
Average Daily Gain ◽  
Acid Synthesis ◽  
Dietary Lipid ◽  
Acetate Incorporation ◽  
Lipid Supplementation

Twenty-four wether lambs were randomly allocated to six treatments to investigate the effect of temperature and dietary lipid supplements on fatty acid synthesis and metabolic activity in sheep. The treatments consisted of four groups exposed to either cold (0 °C) or warm temperature (+23 °C) and given ad libitum access to either a control barley-based diet or with lipid supplementation. Two other groups were placed on the dietary regimen at 0 °C, but pair-fed to intake of animals in the +23 °C environment. At 5 wk, fatty acid synthesis was measured by [1-14C]acetate incorporation into tissue lipids. Cold exposure and dietary lipid supplementation had no effect (P > 0.05) on in vivo fatty acid synthesis rates in either longissimus dorsi or the liver. In both subcutaneous and mesenteric adipose tissue depots, the rate of acetate incorporation into tissue lipid was not significantly affected by cold exposure. In the perirenal fat depot, cold exposure increased (P < 0.05) the rate of fatty acid synthesis, while lipid supplementation decreased (P < 0.05) the rate in all tissue adipose depots. In vitro, mesenteric and perirenal adipose tissues from cold pair-fed animals had higher (P < 0.05) rates of fatty acid synthesis compared to tissues from animals in the warm environment. However, there was no effect of dietary lipid supplementation in these two fat depots. Metabolic heat production, and energy and nitrogen excretion by animals were increased (P < 0.05) by cold exposure while lipid supplementation had the opposite effect (P < 0.05). The relationship between average daily gain and feed intake was linear at both warm and cold environments, but with higher (P < 0.05) average daily gain at all levels of intake in the cold compared to the warm environment. Results indicate that both environment and diet regulate metabolic activity in sheep. However, there were differences in lipogenic response by tissues to the treatments. Key words: Environmental temperature, dietary lipid, fatty acid synthesis, metabolic rate, sheep

Effects of an acute exercise bout in hypoxia on extracellular vesicle release in healthy and prediabetic subjects

2021 ◽  
Author(s):  
Geoffrey Warnier ◽  
Estelle De Groote ◽  
Florian A. Britto ◽  
Ophélie Delcorte ◽  
Joshua P. Nederveen ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Acute Exercise ◽  
Vastus Lateralis ◽  
Venous Blood ◽  
Plasma Concentrations ◽  
Exercise Bout ◽  
Multivesicular Body ◽  
International Standards ◽  
Size Exclusion ◽  
Number Of Particles

Purpose: To investigate exosome-like vesicle (ELV) plasma concentrations and markers of multivesicular body (MVB) biogenesis in skeletal muscle in response to acute exercise. Methods: Seventeen healthy (BMI: 23.5±0.5kg·m-2) and fifteen prediabetic (BMI: 27.3±1.2kg·m-2) men were randomly assigned to two groups performing an acute cycling bout in normoxia or hypoxia (FiO2 14.0%). Venous blood samples were taken before (T0), during (T30) and after (T60) exercise and biopsies from m. vastus lateralis were collected before and after exercise. Plasma ELVs were isolated by size exclusion chromatography, counted by nanoparticle tracking analysis (NTA), and characterized according to international standards, followed by expression analyses of canonical ELV markers in skeletal muscle. Results: In the healthy normoxic group, the total number of particles in the plasma increased during exercise from T0 to T30 (+313%) followed by a decrease from T30 to T60 (-53%). In the same group, an increase in TSG101, CD81 and HSP60 protein expression was measured after exercise in plasma ELVs; however, in the prediabetic group, the total number of particles in the plasma was not affected by exercise. The mRNA content of TSG101, ALIX and CD9 were upregulated in skeletal muscle after exercise in normoxia; whereas, CD9 and CD81 were downregulated in hypoxia. Conclusions: ELV plasma abundance increased in response to acute aerobic exercise in healthy subjects in normoxia, but not in prediabetic subjects, nor in hypoxia. Skeletal muscle analyses suggested that this tissue did not likely play a major role of the exercise-induced increase in circulating ELVs.

scholarly journals In Vivo Ergogenic Properties of the Bifidobacterium longum OLP-01 Isolated from a Weightlifting Gold Medalist

Nutrients ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 2003 ◽  
Author(s):  
Mon-Chien Lee ◽  
Yi-Ju Hsu ◽  
Hsiao-Li Chuang ◽  
Pei-Shan Hsieh ◽  
Hsieh-Hsun Ho ◽  
...  
Keyword(s):  
Grip Strength ◽  
Animal Studies ◽  
Acute Exercise ◽  
Bifidobacterium Longum ◽  
Serum Lactate ◽  
Intestinal Microbiome ◽  
Activity Levels ◽  
Gold Medalist

In recent years, probiotics of human origin have shown superior results and performance compared to probiotics from plant or dairy sources, in both in vitro and animal studies. Towards this end, the current study was conducted to explore the ergogenic properties of Bifidobacterium longum subsp. longum OLP-01 isolated from the intestinal microbiome of the gold medalist from the 2008 Beijing Olympics women’s 48 kg weightlifting competition. Male Institute of Cancer Research (ICR) mice were divided into four groups (n = 10 per group) and orally administered OLP-01 for 4 weeks at 0 (vehicle), 2.05 × 109 (OLP-01-1X), 4.10 × 109 (OLP-01-2X), and 1.03 × 1010 (OLP-01-5X) CFU/kg/day. Physical performance tests including grip strength and endurance time were measured, with OLP-01 supplementation dose-dependently elevating grip strength and endurance. The anti-fatigue activity levels of serum lactate, ammonia, glucose, blood urea nitrogen (BUN), and creatine kinase (CK) were measured after an acute exercise challenge, and OLP-01 was found to significantly decrease lactate, ammonia, and CK levels. OLP-01 treatment was also found to significantly increase the resting levels of both hepatic and muscular glycogen, an indicator of energy storage. Supplementation by OLP-01 showed no subchronic toxic effects while supporting many health-promoting, performance-improving, and fatigue-ameliorating functions.

Effect of hormonal and substrate backgrounds on cell membrane function in normal males

1987 ◽  
Vol 63 (3) ◽  
pp. 1107-1113 ◽  
Author(s):  
G. A. Fantini ◽  
J. P. Roberts ◽  
S. F. Lowry ◽  
J. D. Albert ◽  
K. J. Tracey ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Vastus Lateralis ◽  
Cellular Membrane ◽  
Resting Membrane Potential ◽  
Vastus Lateralis Muscle ◽  
Epinephrine Infusion ◽  
Membrane Function ◽  
Tibialis Muscle ◽  
Group B

Hormonal and substrate influences on in vivo cellular membrane function were evaluated in 15 healthy male volunteers. Each subject underwent serial evaluations of membrane function in the anterior tibialis muscle, as assessed by transcutaneous measurement of resting membrane potential (Em). Group A subjects (n = 9) underwent measurement of resting Em in the basal state and again during the 10th day of intravenous feeding (IVF). Group B subjects (n = 6) underwent measurement of resting Em in the basal state during epinephrine infusion and again during epinephrine infusion on the 7th day of IVF. Percutaneous needle biopsy of the vastus lateralis muscle permitted calculation of transmembrane electrolyte distribution from the Nernst equation, using the measured Em and the chloride space method. Hospitalization with intake of a defined-formula enteral diet for 3 days resulted in depolarization (P less than 0.05) of resting Em (-75.3 +/- 1.6 mV) compared with normal (-79.8 +/- 0.9 mV). Despite 10 days of subsequent IVF, further depolarization (P less than 0.05) of resting Em (-71.2 +/- 1.2 mV) was observed. In the dual presence of IVF and exogenous epinephrine infusion, there was an increase (P less than 0.05) in intracellular potassium concentration and repolarization of resting Em (-80.6 +/- 0.8 mV) to normal levels. These data indicate that hormonal background and substrate availability contribute to the in vivo modulation of cellular membrane function in human skeletal muscle, possibly through facilitation of sodium-dependent amino acid transport across the cell membrane.

scholarly journals Contractile activity-specific transcriptome response to acute endurance exercise and training in human skeletal muscle

2019 ◽  
Vol 316 (4) ◽  
pp. E605-E614 ◽  
Author(s):  
Daniil V. Popov ◽  
Pavel A. Makhnovskii ◽  
Elena I. Shagimardanova ◽  
Guzel R. Gazizova ◽  
Evgeny A. Lysenko ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Transcription Factors ◽  
Human Skeletal Muscle ◽  
Acute Exercise ◽  
Contractile Activity ◽  
Vastus Lateralis ◽  
Aerobic Exercise Training ◽  
Vastus Lateralis Muscle ◽  
Transcriptome Response ◽  
The One

Reduction in daily activity leads to dramatic metabolic disorders, while regular aerobic exercise training is effective for preventing this problem. The purpose of this study was to identify genes that are directly related to contractile activity in human skeletal muscle, regardless of the level of fitness. Transcriptome changes after the one-legged knee extension exercise in exercised and contralateral nonexercised vastus lateralis muscle of seven men were evaluated by RNA-seq. Transcriptome change at baseline after 2 mo of aerobic training (5/wk, 1 h/day) was evaluated as well. Postexercise changes in the transcriptome of exercised muscle were associated with different factors, including circadian oscillations. To reveal transcriptome response specific for endurance-like contractile activity, differentially expressed genes between exercised and nonexercised muscle were evaluated at 1 and 4 h after the one-legged exercise. The contractile activity-specific transcriptome responses were associated only with an increase in gene expression and were regulated mainly by CREB/ATF/AP1-, MYC/MAX-, and E2F-related transcription factors. Endurance training-induced changes (an increase or decrease) in the transcriptome at baseline were more pronounced than transcriptome responses specific for acute contractile activity. Changes after training were associated with widely different biological processes than those after acute exercise and were regulated by different transcription factors (IRF- and STAT-related factors). In conclusion, adaptation to regular exercise is associated not only with a transient (over several hours) increase in expression of many contractile activity-specific genes, but also with a pronounced change (an increase or decrease) in expression of a large number of genes under baseline conditions.

Sign in / Sign up

Export Citation Format

Share Document