Abstract:
NEW FINDINGS:What is the central question of this study? Is electrical pulse stimulation (EPS) an in vitro exercise model able to elicit the hypertrophy of human muscle cells? What is the main finding and its importance? The addition of a restitution period of 8 h after EPS induces the enlargement of human muscle cells, a major physiological end-point to resistance exercise. This is supported by downregulation of myostatin, a negative regulator of muscle mass, and increased phosphorylated mTOR and 4E-BP1, key factors in the growth cascade. This proof-of-concept study provides a model of physiologically mediated muscle growth, which will be the basis for future studies aiming to depict molecular events governing the hypertrophy of human muscle cells. Electrical pulse stimulation (EPS) of muscle cells has previously been used as an in vitro exercise model. The present study aimed to establish an EPS protocol promoting the hypertrophy of human muscle cells, which represents a major physiological end-point to resistance exercise in humans. We hypothesized that adding a resting period after EPS would be crucial for the occurrence of the morphological change. Myoblasts obtained from human muscle biopsies (n = 5) were differentiated into multinucleated myotubes and exposed to 8 h of EPS consisting of 2 ms pulses at 12 V, with a frequency of 1 Hz. Myotube size was assessed using immunohistochemistry immediately, 4 and 8 h after completed EPS. Gene expression and phosphorylation status of selected markers of hypertrophy were assessed using RT-PCR and Western blotting, respectively. Release of the myokine interleukin-6 in culture medium was measured using enzyme-linked immunosorbent assay. We demonstrated a significant increase (31 ± 14%; P = 0.03) in the size of myotubes when EPS was followed by an 8 h resting period, but not immediately or 4 h after completion of EPS. The response was supported by downregulation (P = 0.04) of the gene expression of myostatin, a negative regulator of muscle mass, and an increase in phosphorylated mTOR (P = 0.03) and 4E-BP1 (P = 0.01), which are important factors in the cellular growth signalling cascade. The present work demonstrates that EPS is an in vitro exercise model promoting the hypertrophy of human muscle cells, recapitulating a major physiological end-point to resistance exercise in human skeletal muscle.
journal_name
Exp Physioljournal_title
Experimental physiologyauthors
Tarum J,Folkesson M,Atherton PJ,Kadi Fdoi
10.1113/EP086581subject
Has Abstractpub_date
2017-11-01 00:00:00pages
1405-1413issue
11eissn
0958-0670issn
1469-445Xjournal_volume
102pub_type
杂志文章abstract::Although numerous studies have recently implicated the calcineurin-nuclear factor of activated T-cells (Cn-NFAT) signalling pathway in the regulation of activity-dependent fibre type switching in adult mammalian skeletal muscles, little is known about the endogenous expression of NFAT proteins in the various fibre typ...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.2007.040485
更新日期:2008-03-01 00:00:00
abstract:NEW FINDINGS:What is the topic of this review? Brown fat's role in meal-associated thermogenesis and the related consequences for energy balance regulation with a focus on the gut hormone secretin, which has been identified as the endocrine molecular mediator of meal-associated brown fat thermogenesis. What advances do...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/EP087878
更新日期:2020-08-01 00:00:00
abstract::Indirect evidence supporting a solute-coupled liquid absorption from the pleural space of rabbits has recently been provided; moreover, the beta 2-adrenoceptor agonist terbutaline has been found to increase this absorption. In this study the effect of adrenaline and alpha-adrenoceptor agonists on net rate of liquid ab...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.1997.sp004043
更新日期:1997-05-01 00:00:00
abstract:NEW FINDINGS:What is the central question of this study? What factors influence the onset and magnitude of activation of the neck inspiratory muscles during inspiration? What is the main finding and its importance? Recruitment of the sternocleidomastoid and scalene muscles during inspiration, measured by means of surfa...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/EP087247
更新日期:2019-04-01 00:00:00
abstract::Oxidants have been suggested to enhance contractile function in unfatigued muscle. In this study we aimed to determine the effect of oxidants on "chemically skinned" diaphragm muscle fibre bundles. The sarcoplasmic reticulum and contractile proteins were exposed to superoxide anions (O2-) and hydrogen peroxide (H2O2) ...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/eph8602109
更新日期:2001-03-01 00:00:00
abstract:NEW FINDINGS:What is the central question of this study? Pregnancy requires a robust plasma volume expansion driven by renal sodium retention. In the late-pregnant kidney, the aldosterone-responsive epithelial Na(+) channel is increased, whereas the sodium-chloride cotransporter is decreased. Pendrin has been shown to ...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/EP085396
更新日期:2015-10-01 00:00:00
abstract::The responses of afferent chemosensory fibres of the carotid body to individual chemostimuli have long been established. However, the mechanisms underlying the multiplicative interactions of these stimuli (i.e. how the combined effects of hypoxia and hypercapnia exert a greater effect on afferent nerve discharge than ...
journal_title:Experimental physiology
pub_type: 杂志文章,评审
doi:10.1113/expphysiol.2003.002657
更新日期:2004-01-01 00:00:00
abstract::After food is ingested, nutrients pass through the gastrointestinal tract, stimulating the release of a range of peptide hormones. Among their many local, central and peripheral actions, these hormones act to mediate glucose metabolism and satiety. Indeed, it is the modification of gut hormone secretion that is consid...
journal_title:Experimental physiology
pub_type: 杂志文章,评审
doi:10.1113/expphysiol.2014.079764
更新日期:2014-09-01 00:00:00
abstract::Improved understanding of the processes involved in infarct healing is required for identification of novel therapeutic targets to limit infarct expansion and consequent long-term ventricular remodelling after myocardial infarction. Infarct healing can be modelled effectively in murine models of coronary artery ligati...
journal_title:Experimental physiology
pub_type: 杂志文章,评审
doi:10.1113/expphysiol.2012.064741
更新日期:2013-03-01 00:00:00
abstract:NEW FINDINGS:What is the central question of this study? Compared with Caucasians, African individuals are more susceptible to non-freezing cold injury and experience greater cutaneous vasoconstriction and cooler finger skin temperatures upon hand cooling. We investigated whether the enzyme cyclooxygenase is, in part, ...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/EP086186
更新日期:2017-07-01 00:00:00
abstract::We have examined the surface ultrastructure and morphological characteristics of leucocytes obtained from control rats breathing air and rats made acutely hypoxic (breathing 6% O2, for 30 min). Striking ultrastructural and morphological changes occurred in the leucocytes of hypoxic rats. These changes included the app...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.1993.sp003731
更新日期:1993-11-01 00:00:00
abstract::The role of testosterone (T) in the regulation of cardiovascular function in females is not well understood. Our goal was to examine the effect of T on cardiomyocyte biology by measuring sarcomere shortening/relaxation and intracellular calcium cycling in adult female Sprague-Dawley rats. The rats were divided into th...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.2012.067009
更新日期:2013-01-01 00:00:00
abstract::Beneficial effects of exercise training on the vasculature have been consistently reported in subjects with cardiovascular risk factors or disease, whereas studies in apparently healthy subjects have been less uniform. In this review, we examine evidence pertaining to the impact of exercise training on conduit and res...
journal_title:Experimental physiology
pub_type: 杂志文章,评审
doi:10.1113/expphysiol.2009.048694
更新日期:2011-02-01 00:00:00
abstract:NEW FINDINGS:What is the central question of this study? What mechanisms account for the hypotension observed during chronic elevations in circulating 5-hydroxytryptamine in rats? What is the main finding and its importance? Chronic 5-hydroxytryptamine-induced hypotension requires continued activation of the 5-HT7 rece...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/EP088919
更新日期:2020-10-14 00:00:00
abstract::We have examined the effect of a hyposmotic shock, and thus cell swelling, upon the efflux of amino acids, SO4(2-) and I- from lactating mammary tissue. A hyposmotic challenge increased the efflux of taurine and glycine via a 4,4'-diisothiocyanatostilbene-2,2'- disulphonic acid (DIDS)-sensitive pathway. It appears tha...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.1994.sp003808
更新日期:1994-09-01 00:00:00
abstract::We investigated the permeability of Cs+ and Na+ through various ion channels in rat atrial myocytes using the whole-cell voltage-clamp technique. With isotonic CsCl (140 mM) on both sides of the membrane and nominally [Ca2+]o-free conditions, depolarising clamp pulses induced an increase of outward currents which show...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:
更新日期:2000-03-01 00:00:00
abstract::A global and transient rise of intracellular Ca2+ (Ca2+i) is central to the operation of pump-leak coupling in the frog early distal tubule (EDT). The endoplasmic reticulum (ER) is the site of this Ca2+ release and reuptake; however, it is likely that other intracellular pools, such as mitochondria, also contribute to...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.2004.028886
更新日期:2005-03-01 00:00:00
abstract::Increased fetal lung expansion, induced by tracheal obstruction (TO), is a potent stimulus for fetal lung growth, but rapidly reduces surfactant protein (SP) mRNA levels. Our aim was to determine the time course for the re-expression of the surfactant proteins in fetal lung tissue following the release of a TO and to ...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/eph8602088
更新日期:2001-01-01 00:00:00
abstract::Experiments were carried out to examine the perceived position of the human index finger about the proximal interphalangeal joint. In protocol I, the finger was moved from an intermediate position at velocities ranging from 200 deg/min to 2 deg/min, then held still at one of three positions. The subject's task was vis...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.1992.sp003592
更新日期:1992-03-01 00:00:00
abstract::The endothelial glycocalyx layer of capillaries was stained with Ruthenium Red and examined by transmission electron microscopy in rat extensor hallucis proprius muscles after 2 or 4 days of indirect electrical stimulation via implanted electrodes. The layer appeared continuous on the luminal surface of 63% capillarie...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.1996.sp003989
更新日期:1996-11-01 00:00:00
abstract::The renal medulla contains more mRNA of the inducible isoform of nitric oxide synthase (iNOS) than the cortex, which may be important in preventing ischaemic injury, since blood flow and tissue oxygen tension are normally low in this region. We examined the effects of the bacterial endotoxin E. coli lipopolysaccharide...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/eph8702289
更新日期:2002-03-01 00:00:00
abstract::Previously, we undertook simultaneous recording of ventilation and pulmonary gas exchange in mice and revealed that dopamine D(2) receptors participate in exercise hyperpnoea via behavioural control of ventilation with unchanged pulmonary gas exchange. Here, we examined the hypothesis that D(1) receptors also contribu...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.2012.068312
更新日期:2013-02-01 00:00:00
abstract::What is the central question of this study? Can a modern proportional assist ventilator (PAV) function sufficiently well to unload the respiratory muscles during exercise? What is the main finding and its importance? A PAV can be constructed with contemporary hardware and software and be used at all exercise intensiti...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/EP085735
更新日期:2016-06-01 00:00:00
abstract::Current assessments of the effects of shear patterns on vascular function assume that a parabolic velocity profile is always present. Any substantial deviation in the profile away from this may result in misinterpretation of the importance that shear patterns have on vascular function. The present investigation tested...
journal_title:Experimental physiology
pub_type: 杂志文章,随机对照试验
doi:10.1113/expphysiol.2011.064212
更新日期:2012-07-01 00:00:00
abstract::Very brief and intense exercise triggers a biphasic metabolic and respiratory response with a second phase that occurs after the cessation of the muscular activity. The effects on minute ventilation (V(E)) produced by manipulation of the peripheral circulation in metabolically active muscles could thus be studied with...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1111/j.1469-445x.2001.tb00041.x
更新日期:2001-11-01 00:00:00
abstract::Recently attempts have been made to analyse blood pressure (BP) and renal sympathetic nerve activity (RSNA) to determine how patterns contained within them might reflect control by the autonomic nervous system. To date, these studies have primarily used coherence analysis of BP and RSNA in the frequency domain. Howeve...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1111/j.1469-445x.2002.tb00059.x
更新日期:2002-07-01 00:00:00
abstract::Effects of altered maternal salt intake between 122 and 127 days gestation (term is 150 days) were studied in eight fetuses carried by ewes which had renal insufficiency caused by subtotal nephrectomy (STNxF) and seven fetuses carried by intact ewes (IntF). Plasma sodium and osmolality were increased in ewes with subt...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.2007.039149
更新日期:2008-02-01 00:00:00
abstract::Joint movement was recently shown to stimulate the secretion of the lubricant hyaluronan (HA); also, exercise therapy and intra-articular hyaluronan injections are used to treat moderate osteoarthritis. The present study quantifies the stimulus-response curves for HA secretion in vivo and reports a role of transcripti...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.2008.045203
更新日期:2009-03-01 00:00:00
abstract::The pattern of propagation of slow waves in the small intestine is not clear. Specifically, it is not known whether propagation is determined by a single dominant ICC-MP (Interstitial cells of Cajal located in the Myenteric Plexus) pacemaker unit or whether there are multiple active pacemakers. To determine this patte...
journal_title:Experimental physiology
pub_type: 杂志文章
doi:10.1113/expphysiol.2007.039180
更新日期:2008-03-01 00:00:00
abstract::Embryonic stem (ES) cells are pluripotent cells isolated from the inner cell mass of blastocysts. ES cells are able to differentiate into the three primitive layers (endoderm, mesoderm and ectoderm) of the organism, including the germline. To study early stages of development, as well as to investigate the impact of a...
journal_title:Experimental physiology
pub_type: 杂志文章,评审
doi:
更新日期:2000-11-01 00:00:00