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Sample records for exercise induces biphasic

  1. Acute exercise induces biphasic increase in respiratory mRNA in skeletal muscle

    SciTech Connect

    Ikeda, Shin-ichi; Kizaki, Takako; Haga, Shukoh; Ohno, Hideki; Takemasa, Tohru

    2008-04-04

    Peroxisome proliferator-activated receptor {gamma} coactivator-1{alpha} (PGC-1{alpha}) promotes the expression of oxidative enzymes in skeletal muscle. We hypothesized that activation of the p38 MAPK (mitogen-activated protein kinase) in response to exercise was associated with exercise-induced PGC-1{alpha} and respiratory enzymes expression and aimed to demonstrate this under the physiological level. We subjected mice to a single bout of treadmill running and found that the exercise induced a biphasic increase in the expression of respiratory enzymes mRNA. The second phase of the increase was accompanied by an increase in PGC-1{alpha} protein, but the other was not. Administration of SB203580 (SB), an inhibitor of p38 MAPK, suppressed the increase in PGC-1{alpha} expression and respiratory enzymes mRNA in both phases. These data suggest that p38 MAPK is associated with the exercise-induced expression of PGC-1{alpha} and biphasic increase in respiratory enzyme mRNAs in mouse skeletal muscle under physiological conditions.

  2. Exercise-Induced Bronchoconstriction

    MedlinePlus

    ... Conditions & Treatments ▸ Conditions Dictionary ▸ Exercise-Induced Bronchoconstriction Share | Exercise-Induced Bronchoconstriction (EIB) « Back to A to Z Listing Exercise-Induced Bronchoconstriction, (EIB), often known as exercise-induced ...

  3. Biphasic response of cardiodynamic adaptations to swimming exercise in rats.

    PubMed

    Stojanovic Tosic, Jelica T; Jakovljevic, Vladimir Lj; Zivkovic, Vladimir V; Srejovic, Ivan M; Valdevit, Zoran J; Radovanovic, Dragan S; Djuric, Dragan M; Ahmetovic, Zlatko K; Peric, Dusan B; Cankovic, Marija B; Jovanovic, Maja S; Djordjevic, Dusica Z

    2015-07-01

    The aim of research was to assess exercise-induced changes in mechanics of hearts isolated from rats, as well as time-course of those changes. Wistar rats (n = 42) were divided into control, moderately trained (swimming 1 hour, 5 days a week for 9 or 12 weeks) and strenuously trained (swimming 2, 3 and 4 times a day for an hour in weeks 10, 11 and 12, respectively) groups. After sacrificing, hearts (weight: 1480.82 ± 145.38 mg) were isolated and perfused on a Langendorff apparatus. Coronary perfusion pressure (CPP) was gradually increased (from 40 to 120 cm H(2)O) in order to establish coronary autoregulation. Parameters of cardiac contractility were recorded: maximum and minimum rate of change of pressure in the left ventricle (dp/dt max and dp/dt min), systolic and diastolic left ventricular pressure (SLVP and DLVP), heart rate (HR) and coronary flow (CF). Nine weeks of moderate exercise induced slight depression of coronary function (decrease of dp/dt max, dp/dt min, SLVP and DLVP), while 3 additional weeks of moderate training improved hearts function, but not to the extent that the strenuous training program did. The results of our study add evidence about beneficial effects of regular moderate exercise on heart, and furthermore, show that exercising frequently, if the intensity stays within moderate range, may not have detrimental effects on cardiodynamics. PMID:25816361

  4. Exercise-induced asthma

    MedlinePlus

    Wheezing - exercise-induced; Reactive airway disease - exercise ... Having asthma symptoms when you exercise does not mean you cannot or should not exercise. But be aware of your EIA triggers. Cold or dry air may ...

  5. Biphasic cardiovascular and respiratory effects induced by β-citronellol.

    PubMed

    Ribeiro-Filho, Helder Veras; de Souza Silva, Camila Meirelles; de Siqueira, Rodrigo JoséBezerra; Lahlou, Saad; dos Santos, Armênio Aguiar; Magalhães, Pedro Jorge Caldas

    2016-03-15

    β-Citronellol is a monoterpene found in the essential oil of various plants with antihypertensive properties. In fact, β-citronellol possesses hypotensive actions due to its vasodilator abilities. Here we aimed to show that β-citronellol recruits airway sensory neural circuitry to evoke cardiorespiratory effects. In anesthetized rats, intravenous injection of β-citronellol caused biphasic hypotension, bradycardia and apnea. Bilateral vagotomy, perivagal capsaicin treatment or injection into the left ventricle abolished first rapid phase (named P1) but not delayed phase P2 of the β-citronellol effects. P1 persisted after pretreatment with capsazepine, ondansetron, HC-030031 or suramin. Suramin abolished P2 of apnea. In awake rats, β-citronellol induced biphasic hypotension and bradycardia being P1 abolished by methylatropine. In vitro, β-citronellol inhibited spontaneous or electrically-evoked contractions of rat isolated right or left atrium, respectively, and fully relaxed sustained contractions of phenylephrine in mesenteric artery rings. In conclusion, chemosensitive pulmonary vagal afferent fibers appear to mediate the cardiovascular and respiratory effects of β-citronellol. The transduction mechanism in P1 seems not to involve the activation of transient receptor potential vanilloid subtype 1 (TRPV1), transient receptor potential ankyrin subtype 1 (TRPA1), purinergic (P2X) or 5-HT3 receptors located on airways sensory nerves. P2 of hypotension and bradycardia seems resulting from a cardioinhibitory and vasodilatory effect of β-citronellol and the apnea from a purinergic signaling. PMID:26872991

  6. Biphasic response of plasma endothelin-1 concentration to exhausting submaximal exercise in man.

    PubMed

    Richter, E A; Emmeluth, C; Bie, P; Helge, J; Kiens, B

    1994-07-01

    The concentration of endothelin-1 in forearm venous plasma was measured in 10 healthy men at rest and during ergometer bicycling at 65% of maximal aerobic capacity until exhaustion (96 +/- 10 min, mean +/- SE). A control group of 10 comparable subjects rested for 2 h. Mean plasma endothelin-1 concentration at rest was 2.0 +/- 0.2 pg ml-1, n = 20. The concentration decreased significantly by 21% during the first 30 min of exercise, whereupon it increased so that the concentration after 60 min of exercise was no different from resting values. The change in endothelin concentration could not be explained by changes in plasma volume. Unspecific effects of catheterization or time could also not explain the change in endothelin-1, since in the 10 control subjects who did not exercise, plasma endothelin-1 did not change significantly over 120 min. It is concluded that the concentration of endothelin-1 in forearm venous plasma changes in a biphasic manner during prolonged exhaustive bicycle exercise in man. An initial decrease in concentration is followed by an increase restoring the concentration to resting values after 60 min exercise. PMID:7955935

  7. [Exercise-induced bronchoconstriction].

    PubMed

    Hildebrand, Katarzyna

    2011-01-01

    Terms exercise-induced asthma (EIA) or exercise-induced bronchoconstriction (EIB) are used to describe transient bronchoconstriction occurring during or immediately after vigorous exercise in some subjects. For the diagnosis of EIB it is necessary to show at least 10% decrease in FEV1 from baseline following physical exercise. The prevalence of EIB has been reported to be 12-15% in general population, 10-20% in summer olympic athletes, affecting up to 50-70% of winter athletes (particularly ski runners and skaters). There are two key theories explaining EIB: thermal and osmotic. Differential diagnosis of EIB should include chronic cardio-pulmonary diseases, vocal cord dysfunction, hyperventilation syndrome and poor physical fitness or overtraining. According to the ATS guidelines from 1999 for the diagnosis of EIB a standardized exercise on a treadmill or cycle ergometer test with stable environmental conditions regarding temperature and humidity of inhaled air, should be employed. Other laboratory tests assessing bronchial hyperresponsiveness to indirect stimuli including eucapnic voluntary hyperpnea (EVH), mannitol, hypertonic saline, AMP or measurement of exhaled nitric oxide (FENO) are also successfully used. In the prevention of EIB include both pharmacologic and non-pharmacologic treatment. In patients with poorly controlled asthma intensification of anti-inflammatory treatment can decrease the frequency and severity of EIB. Short and long acting beta2-agonists, antileukotriene drugs can be used prior to exercise to prevent EIB. PMID:21190152

  8. Exercise-induced purpura.

    PubMed

    Ramelet, Albert-Adrien

    2004-01-01

    Exercise-induced purpura (EIP) occurs on the lower legs after unusual or major muscular activity, as in marathon runners or as after long walks, especially in the mountains in hot weather. In leisure walkers, patients are otherwise healthy females. There is no relation with chronic venous disorder. Erythematous, urticarial or purpuric plaques arise on the lower leg, usually sparing the skin compressed by socks. Symptoms include itch, pain and a burning sensation. Histopathology demonstrates leukocytoclastic vasculitis. The lesions fade after some days, with frequent relapses at further muscular exercises and may be prevented in some cases by compression, intake of venoactive drugs and local application of steroids. EIP is not uncommon, even if very few descriptions have yet been published. It appears to be consecutive to venous stasis induced by an acute failure of the muscle pump of the calf and thermoregulation decompensation, after a prolonged and unusual exercise, such as running or walking in hot weather. PMID:15178910

  9. Monophasic and Biphasic Electrical Stimulation Induces a Precardiac Differentiation in Progenitor Cells Isolated from Human Heart

    PubMed Central

    Pietronave, Stefano; Zamperone, Andrea; Oltolina, Francesca; Colangelo, Donato; Follenzi, Antonia; Novelli, Eugenio; Diena, Marco; Pavesi, Andrea; Consolo, Filippo; Fiore, Gianfranco Beniamino; Soncini, Monica

    2014-01-01

    Electrical stimulation (ES) of cells has been shown to induce a variety of responses, such as cytoskeleton rearrangements, migration, proliferation, and differentiation. In this study, we have investigated whether monophasic and biphasic pulsed ES could exert any effect on the proliferation and differentiation of human cardiac progenitor cells (hCPCs) isolated from human heart fragments. Cells were cultured under continuous exposure to monophasic or biphasic ES with fixed cycles for 1 or 3 days. Results indicate that neither stimulation protocol affected cell viability, while the cell shape became more elongated and reoriented more perpendicular to the electric field direction. Moreover, the biphasic ES clearly induced the upregulation of early cardiac transcription factors, MEF2D, GATA-4, and Nkx2.5, as well as the de novo expression of the late cardiac sarcomeric proteins, troponin T, cardiac alpha actinin, and SERCA 2a. Both treatments increased the expression of connexin 43 and its relocation to the cell membrane, but biphasic ES was faster and more effective. Finally, when hCPCs were exposed to both monophasic and biphasic ES, they expressed de novo the mRNA of the voltage-dependent calcium channel Cav 3.1(α1G) subunit, which is peculiar of the developing heart. Taken together, these results show that ES alone is able to set the conditions for early differentiation of adult hCPCs toward a cardiac phenotype. PMID:24328510

  10. Exercise-Induced Bronchospasm

    MedlinePlus

    ... symptoms of EIB. Avoid exercising in extremely cold temperatures or when you have a respiratory infection, such ... by T Sinha, MD; AK David, MD (American Family Physician February 15, 2003, http://www.aafp.org/ ...

  11. Biphasic effects of direct, but not indirect, GABA mimetics and antagonists on haloperidol-induced catalepsy.

    PubMed

    Worms, P; Lloyd, K G

    1980-03-01

    At very low doses the GABA agonists SL 76002 and muscimol diminish haloperidol-induced catalepsy. At somewhat higher doses these compounds potentiate catalepsy. Biphasic effects on DA-receptor mediated functions have previously been noted with bicuculline and picrotoxinin. In contrast, manipulation of GABA levels by enzyme inhibition induced only a monophasic effect on dopamine-mediated behaviour. The potentiation of GABA levels by enzyme inhibition induced only a monophasic effect on dopamine-mediated behaviour. The potentiation of haloperidol-induced catalepsy by GABA mimetics is also observed with dipropylacetate, delta-aminovaleric acid and gamma-acetylenic GABA. This GABA-mimetic potentiation of catakepsy was blocked by the coadministration of bicuculline. These results confirm and extend the hypothesis that GABA-neurons influence DA neuron function. Furthermore they suggest that more than one group of GABA receptors influence directly and/or indirectly DA neuronal function, with different resultant effects. PMID:7189827

  12. Adolescents and Exercise Induced Asthma

    ERIC Educational Resources Information Center

    Hansen, Pamela; Bickanse, Shanna; Bogenreif, Mike; VanSickle, Kyle

    2008-01-01

    This article defines asthma and exercise induced asthma, and provides information on the triggers, signs, and symptoms of an attack. It also gives treatments for these conditions, along with prevention guidelines on how to handle an attack in the classroom or on the practice field. (Contains 2 tables and 1 figure.)

  13. Exercise-induced oxidative stress and hypoxic exercise recovery.

    PubMed

    Ballmann, Christopher; McGinnis, Graham; Peters, Bridget; Slivka, Dustin; Cuddy, John; Hailes, Walter; Dumke, Charles; Ruby, Brent; Quindry, John

    2014-04-01

    Hypoxia due to altitude diminishes performance and alters exercise oxidative stress responses. While oxidative stress and exercise are well studied, the independent impact of hypoxia on exercise recovery remains unknown. Accordingly, we investigated hypoxic recovery effects on post-exercise oxidative stress. Physically active males (n = 12) performed normoxic cycle ergometer exercise consisting of ten high:low intensity intervals, 20 min at moderate intensity, and 6 h recovery at 975 m (normoxic) or simulated 5,000 m (hypoxic chamber) in a randomized counter-balanced cross-over design. Oxygen saturation was monitored via finger pulse oximetry. Blood plasma obtained pre- (Pre), post- (Post), 2 h post- (2Hr), 4 h post- (4Hr), and 6 h (6Hr) post-exercise was assayed for Ferric Reducing Ability of Plasma (FRAP), Trolox Equivalent Antioxidant Capacity (TEAC), Lipid Hydroperoxides (LOOH), and Protein Carbonyls (PC). Biopsies from the vastus lateralis obtained Pre and 6Hr were analyzed by real-time PCR quantify expression of Heme oxygenase 1 (HMOX1), Superoxide Dismutase 2 (SOD2), and Nuclear factor (euthyroid-derived2)-like factor (NFE2L2). PCs were not altered between trials, but a time effect (13 % Post-2Hr increase, p = 0.044) indicated exercise-induced blood oxidative stress. Plasma LOOH revealed only a time effect (p = 0.041), including a 120 % Post-4Hr increase. TEAC values were elevated in normoxic recovery versus hypoxic recovery. FRAP values were higher 6Hr (p = 0.045) in normoxic versus hypoxic recovery. Exercise elevated gene expression of NFE2L2 (20 % increase, p = 0.001) and SOD2 (42 % increase, p = 0.003), but hypoxic recovery abolished this response. Data indicate that recovery in a hypoxic environment, independent of exercise, may alter exercise adaptations to oxidative stress and metabolism. PMID:24384982

  14. Shock-induced termination of reentrant cardiac arrhythmias: Comparing monophasic and biphasic shock protocols

    SciTech Connect

    Bragard, Jean Simic, Ana; Elorza, Jorge; Grigoriev, Roman O.; Fenton, Flavio H.; Cherry, Elizabeth M.; Gilmour, Robert F.; Otani, Niels F.

    2013-12-15

    In this article, we compare quantitatively the efficiency of three different protocols commonly used in commercial defibrillators. These are based on monophasic and both symmetric and asymmetric biphasic shocks. A numerical one–dimensional model of cardiac tissue using the bidomain formulation is used in order to test the different protocols. In particular, we performed a total of 4.8 × 10{sup 6} simulations by varying shock waveform, shock energy, initial conditions, and heterogeneity in internal electrical conductivity. Whenever the shock successfully removed the reentrant dynamics in the tissue, we classified the mechanism. The analysis of the numerical data shows that biphasic shocks are significantly more efficient (by about 25%) than the corresponding monophasic ones. We determine that the increase in efficiency of the biphasic shocks can be explained by the higher proportion of newly excited tissue through the mechanism of direct activation.

  15. Shock-induced termination of reentrant cardiac arrhythmias: Comparing monophasic and biphasic shock protocols

    NASA Astrophysics Data System (ADS)

    Bragard, Jean; Simic, Ana; Elorza, Jorge; Grigoriev, Roman O.; Cherry, Elizabeth M.; Gilmour, Robert F.; Otani, Niels F.; Fenton, Flavio H.

    2013-12-01

    In this article, we compare quantitatively the efficiency of three different protocols commonly used in commercial defibrillators. These are based on monophasic and both symmetric and asymmetric biphasic shocks. A numerical one-dimensional model of cardiac tissue using the bidomain formulation is used in order to test the different protocols. In particular, we performed a total of 4.8 × 106 simulations by varying shock waveform, shock energy, initial conditions, and heterogeneity in internal electrical conductivity. Whenever the shock successfully removed the reentrant dynamics in the tissue, we classified the mechanism. The analysis of the numerical data shows that biphasic shocks are significantly more efficient (by about 25%) than the corresponding monophasic ones. We determine that the increase in efficiency of the biphasic shocks can be explained by the higher proportion of newly excited tissue through the mechanism of direct activation.

  16. Epinephrine Treatment is Infrequent and Biphasic Reactions Are Rare in Food-Induced Reactions During Oral Food Challenges in Children

    PubMed Central

    Järvinen, Kirsi M.; Amalanayagam, Sujitha; Shreffler, Wayne G.; Noone, Sally; Sicherer, Scott H.; Sampson, Hugh A.; Nowak-Węgrzyn, Anna

    2009-01-01

    Background Data about epinephrine utilization and biphasic reactions in childhood food-induced anaphylaxis during oral food challenges are scarce. Objective To determine the prevalence and risk factors of reactions requiring epinephrine and the rate of biphasic reactions during oral food challenges (OFCs) in children. Methods Reaction details of positive OFCs in children between 1999 and 2007 were collected using a computerized database. Selection of patients for OFCs was generally predicated on ≤50% likelihood of a positive challenge and a low likelihood of a severe reaction based on the clinical history, specific IgE levels, and skin prick tests (SPTs). Results A total of 436 of 1273 OFCs resulted in a reaction (34%). Epinephrine was administered in 50 challenges (11% of positive challenges, 3.9% overall); for egg (n=15, 16% of positive OFCs to egg), milk (n=14, 12%), peanut (n=10, 26%), tree nuts (n=4, 33%), soy (n=3, 7%), wheat (n=3, 9%), and fish (n=1, 9%). Reactions requiring epinephrine occurred in older children (median 7.9 vs. 5.8 years, P<0.001), and were more often caused by peanuts (P=0.006) when compared to reactions not treated with epinephrine. There was no difference in the gender, prevalence of asthma, history of anaphylaxis, specific IgE level, SPTs, or amount of food administered. Two doses of epinephrine were required in 3/50 patients (6%) reacting to wheat, cow’s milk, and pistachio. There was one (2%) biphasic reaction. No reaction resulted in life-threatening respiratory or cardiovascular compromise. Conclusion Older age and reactions to peanuts were risk factors for anaphylaxis during oral food challenges. Reactions requiring multiple doses of epinephrine and biphasic reactions were infrequent. PMID:20004784

  17. Exercise-induced asthma: an overview.

    PubMed

    Cummiskey, J

    2001-10-01

    Asthmatic attack in exercise-induced asthma is brought about by hyperventilation (not necessarily to exercise), cold air, and low humidity of the air breathed. The effects are an increase in airway resistance, damage to bronchial mucosa, and an increase in bronchovascular permeability. The mechanism of these changes is the release of mediators such as histamine, leukotrienes, nitric oxide, sensory neuropeptides, the inhibition of neuronal activity, and bronchovascular permeability. The cause of asthma and exercise-induced asthma is unknown. It is probably an abnormality of vascular control in the peribronchium and/or an alteration in local adrenergic function. The importance of exercise-induced asthma definition and the use of stimulants in sport and antidoping in sport are discussed. PMID:11678516

  18. AIC649 Induces a Bi-Phasic Treatment Response in the Woodchuck Model of Chronic Hepatitis B

    PubMed Central

    Paulsen, Daniela; Weber, Olaf; Ruebsamen-Schaeff, Helga; Tennant, Bud C.; Menne, Stephan

    2015-01-01

    AIC649 has been shown to directly address the antigen presenting cell arm of the host immune defense leading to a regulated cytokine release and activation of T cell responses. In the present study we analyzed the antiviral efficacy of AIC649 as well as its potential to induce functional cure in animal models for chronic hepatitis B. Hepatitis B virus transgenic mice and chronically woodchuck hepatitis virus (WHV) infected woodchucks were treated with AIC649, respectively. In the mouse system AIC649 decreased the hepatitis B virus titer as effective as the “gold standard”, Tenofovir. Interestingly, AIC649-treated chronically WHV infected woodchucks displayed a bi-phasic pattern of response: The marker for functional cure—hepatitis surface antigen—first increased but subsequently decreased even after cessation of treatment to significantly reduced levels. We hypothesize that the observed bi-phasic response pattern to AIC649 treatment reflects a physiologically “concerted”, reconstituted immune response against WHV and therefore may indicate a potential for inducing functional cure in HBV-infected patients. PMID:26656974

  19. AIC649 Induces a Bi-Phasic Treatment Response in the Woodchuck Model of Chronic Hepatitis B.

    PubMed

    Paulsen, Daniela; Weber, Olaf; Ruebsamen-Schaeff, Helga; Tennant, Bud C; Menne, Stephan

    2015-01-01

    AIC649 has been shown to directly address the antigen presenting cell arm of the host immune defense leading to a regulated cytokine release and activation of T cell responses. In the present study we analyzed the antiviral efficacy of AIC649 as well as its potential to induce functional cure in animal models for chronic hepatitis B. Hepatitis B virus transgenic mice and chronically woodchuck hepatitis virus (WHV) infected woodchucks were treated with AIC649, respectively. In the mouse system AIC649 decreased the hepatitis B virus titer as effective as the "gold standard", Tenofovir. Interestingly, AIC649-treated chronically WHV infected woodchucks displayed a bi-phasic pattern of response: The marker for functional cure--hepatitis surface antigen--first increased but subsequently decreased even after cessation of treatment to significantly reduced levels. We hypothesize that the observed bi-phasic response pattern to AIC649 treatment reflects a physiologically "concerted", reconstituted immune response against WHV and therefore may indicate a potential for inducing functional cure in HBV-infected patients. PMID:26656974

  20. Mechanisms of Exercise-Induced Hypoalgesia

    PubMed Central

    Koltyn, Kelli F.; Brellenthin, Angelique G.; Cook, Dane B.; Sehgal, Nalini; Hillard, Cecilia

    2014-01-01

    The purpose of this study was to examine opioid and endocannabinoid mechanisms of exercise-induced hypoalgesia (EIH). Fifty-eight men and women (mean age = 21 yrs) completed three sessions. During the first session, participants were familiarized with the temporal summation of heat pain and pressure pain protocols. In the exercise sessions, following double-blind administration of either an opioid antagonist (50 mg naltrexone) or placebo, participants rated the intensity of heat pulses and indicated their pressure pain thresholds (PPT) and ratings (PPR) before and after 3 minutes of submaximal isometric exercise. Blood was drawn before and after exercise. Results indicated circulating concentrations of two endocannabinoids, N-arachidonylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG) as well as related lipids oleoylethanolamide (OEA), palmitoylethanolamide (PEA), N-docsahexaenoylethanolamine (DHEA), and 2-oleoylglycerol (2-OG) increased significantly (p < 0.05) following exercise. PPT increased significantly (p < 0.05) while PPR decreased significantly (p < 0.05) following exercise. Also, temporal summation ratings were significantly lower (p < 0.05) following exercise. These changes in pain responses did not differ between placebo or naltrexone conditions (p > 0.05). A significant association was found between EIH and DHEA. These results suggest involvement of a non-opioid mechanism in EIH following isometric exercise. PMID:25261342

  1. Telocytes in exercise-induced cardiac growth.

    PubMed

    Xiao, Junjie; Chen, Ping; Qu, Yi; Yu, Pujiao; Yao, Jianhua; Wang, Hongbao; Fu, Siyi; Bei, Yihua; Chen, Yan; Che, Lin; Xu, Jiahong

    2016-05-01

    Exercise can induce physiological cardiac growth, which is featured by enlarged cardiomyocyte cell size and formation of new cardiomyocytes. Telocytes (TCs) are a recently identified distinct interstitial cell type, existing in many tissues and organs including heart. TCs have been shown to form a tandem with cardiac stem/progenitor cells in cardiac stem cell niches, participating in cardiac regeneration and repair. Although exercise-induced cardiac growth has been confirmed as an important way to promote cardiac regeneration and repair, the response of cardiac TCs to exercise is still unclear. In this study, 4 weeks of swimming training was used to induce robust healthy cardiac growth. Exercise can induce an increase in cardiomyocyte cell size and formation of new cardiomyocytes as determined by Wheat Germ Lectin and EdU staining respectively. TCs were identified by three immunofluorescence stainings including double labelling for CD34/vimentin, CD34/platelet-derived growth factor (PDGF) receptor-α and CD34/PDGF receptor-β. We found that cardiac TCs were significantly increased in exercised heart, suggesting that TCs might help control the activity of cardiac stem/progenitor cells, cardiomyocytes or endothelial cells. Adding cardiac TCs might help promote cardiac regeneration and renewal. PMID:26987685

  2. Exercise-induced airways constriction 1

    PubMed Central

    Simonsson, Bo G.; Skoogh, B-E.; Ekström-Jodal, B.

    1972-01-01

    Airway conductance was measured in a body plethysmograph at different lung volumes before and after graded exercise. In 14 out of 19 patients, mostly asthmatics, airway conductance fell significantly after exercise. These subjects also showed other signs of an increased bronchial reactivity to different stimuli, including forced breathing, hyperventilation, and cold air, but they had no exogenous allergy. The exercise-induced bronchoconstriction could be blocked by atropine in six of the nine patients tested. Exercise-induced bronchoconstriction in patients with clinical and physiological evidence of increased airway reactivity thus seems to be primarily mediated via a vagal reflex, probably from hyperresponsive airway mechanoreceptors reacting to increased ventilatory flow or lung distension. No relation was found between PaCO2 or pH and the severity of airways constriction. Cromoglycic acid failed to block the exercise reaction in five of the six hyperreactive patients tested. In addition to or following the vagal reflex a disturbed relation between beta and alpha receptors in bronchial muscles or a release of humoral spasmogens may contribute to the progression of post-exercise airways constriction. PMID:4624586

  3. Bioabsorbable zinc ion induced biphasic cellular responses in vascular smooth muscle cells

    PubMed Central

    Ma, Jun; Zhao, Nan; Zhu, Donghui

    2016-01-01

    Bioabsorbable metal zinc (Zn) is a promising new generation of implantable scaffold for cardiovascular and orthopedic applications. In cardiovascular stent applications, zinc ion (Zn2+) will be gradually released into the surrounding vascular tissues from such Zn-containing scaffolds after implantation. However, the interactions between vascular cells and Zn2+ are still largely unknown. We explored the short-term effects of extracellular Zn2+ on human smooth muscle cells (SMCs) up to 24 h, and an interesting biphasic effect of Zn2+ was observed. Lower concentrations (<80 μM) of Zn2+ had no adverse effects on cell viability but promoted cell adhesion, cell spreading, cell proliferation, cell migration, and enhanced the expression of F-actin and vinculin. Cells treated with such lower concentrations of Zn2+ displayed an elongated shape compared to controls without any treatment. In contrast, cells treated with higher Zn2+ concentrations (80–120 μM) had opposite cellular responses and behaviors. Gene expression profiles revealed that the most affected functional genes were related to angiogenesis, inflammation, cell adhesion, vessel tone, and platelet aggregation. Results indicated that Zn has interesting concentration-dependent biphasic effects on SMCs with low concentrations being beneficial to cellular functions. PMID:27248371

  4. Bioabsorbable zinc ion induced biphasic cellular responses in vascular smooth muscle cells.

    PubMed

    Ma, Jun; Zhao, Nan; Zhu, Donghui

    2016-01-01

    Bioabsorbable metal zinc (Zn) is a promising new generation of implantable scaffold for cardiovascular and orthopedic applications. In cardiovascular stent applications, zinc ion (Zn(2+)) will be gradually released into the surrounding vascular tissues from such Zn-containing scaffolds after implantation. However, the interactions between vascular cells and Zn(2+) are still largely unknown. We explored the short-term effects of extracellular Zn(2+) on human smooth muscle cells (SMCs) up to 24 h, and an interesting biphasic effect of Zn(2+) was observed. Lower concentrations (<80 μM) of Zn(2+) had no adverse effects on cell viability but promoted cell adhesion, cell spreading, cell proliferation, cell migration, and enhanced the expression of F-actin and vinculin. Cells treated with such lower concentrations of Zn(2+) displayed an elongated shape compared to controls without any treatment. In contrast, cells treated with higher Zn(2+) concentrations (80-120 μM) had opposite cellular responses and behaviors. Gene expression profiles revealed that the most affected functional genes were related to angiogenesis, inflammation, cell adhesion, vessel tone, and platelet aggregation. Results indicated that Zn has interesting concentration-dependent biphasic effects on SMCs with low concentrations being beneficial to cellular functions. PMID:27248371

  5. Exercise-induced anaphylaxis and antileukotriene montelukast.

    PubMed

    Gajbhiye, Sapna; Agrawal, Rajendra Prasad; Atal, Shubham; Tiwari, Vikalp; Phadnis, Pradeep

    2015-01-01

    We report a rare case of exercise-induced anaphylaxis (EIA), occurring exclusively with exercise, without any other associated trigger, detected in the prodromal phase, and prevented from additional anaphylaxis episodes by treatment with cetirizine and 10 mg daily of antileukotriene montelukast to date. EIA is a syndrome in which patients experience a spectrum of the symptoms of anaphylaxis ranging from mild cutaneous signs to severe systemic manifestations such as hypotension, syncope, and even death after increased physical activity. Many people have triggers, such as, a variety of foods, various medications, alcohol, cold weather, humidity, and seasonal and hormonal changes along with exercise that cause the symptoms. Typically, either exercise or the specific trigger alone will rarely cause symptoms. It is differentiated from cholinergic urticaria by the absence of response to passive body warming and emotional stress. PMID:26312002

  6. Cancer: brain-regulated biphasic stress response induces cell growth or cell death to adapt to psychological stressors.

    PubMed

    Thomas, Charles; Bhatia, Shruti

    2014-01-01

    According to Indian Vedic philosophy, a human being contains 3 major bodies: (1) the matter body--brain, organs, and senses; (2) the mental body--mind, individual consciousness, intellect, and ego; and (3) the soul or causal body--universal consciousness. The third, which is located in the heart according to all spiritual traditions and recent scientific literature, can be seen as the information body that contains all memories. The mental body, which can interface with the matter and information bodies, can be seen as a field of immaterial energy that can carry, regulate, and strengthen all information (eg, thoughts or emotions) both positively and negatively. This body of information may store ancestral and/or autobiographical memories: unconscious memories from inner traumas--inner information (Ii) or samskaras in Vedic philosophy--and conscious memories from outer traumas--outer information (Io). These conscious and unconscious memories can be seen as potential psychological stressors. Resonance between Ii and Io may induce active conflicts if resistance occurs in the mental body; this conflict may cause specific metabolic activity in the brain and a stress response in the physical body, which permits adjustment to psychological stressors. The brainregulated stress response may be biphasic: cell death or growth induced by adrenergic molecular pathways during the conflict's unresolved phase and reversion to cell growth or death induced by cholinergic molecular pathways during the conflict's resolved phase. Case studies and data mining from PubMed suggest that this concept complies with the principles of holistic medicine and the scientific literature supporting its benefits. We suggest that the evolution of cancer can be seen as a biphasic stress response regulated by the brain to adapt to psychological stressors, which produce imbalance among the physical, mental, and information bodies. PMID:25141354

  7. Biphasic effects of histamine on ethanol-induced gastric mucosal lesions: Studies with betahistine, dimaprit, (R). alpha. -methylhistamine and nizatidine

    SciTech Connect

    Morales, R.E.; Palitzsch, K.D.; Szabo, S. )

    1991-03-15

    In elucidating further the role that histamine (H) may play in gastroprotection against hemorrhagic mucosal lesions (HML) induced by ethanol (E), fasted S-D rats were treated with subcutaneous (s.c.) H 10, 15, 20 and 30 min before intragastric (i.g.) 100% E or H-agonists betahistine (H1) or dimaprit (H2) i.g. 30 min. before 75% E. All animals were killed 1 hr after E, HML were measured with stereomicrosopic planimetry and expressed as % of glandular stomach. The H2 antagonist nizatidine did not influence the extent of HML. As a follow up to previously reported nizatidine blockade of H2-induced gastroprotection against 75% E, nizatidine + H1 or nizatidine + H3 agonist (R){alpha}-methylhistamine was also tested. The H2 antagonist nizatidine abolished the gastroprotection by H3 but did not influence the H1-induced reduction of HML. H injected s.c. showed a dose- and time-dependent biphasic effect on E-induced gastric mucosal lesions. Both H1- and H2-agonists injected s.c. reduced the E-induced damage. Nizatidine alone failed to influence mucosal lesions, blocked gastroprotection induced by H2 or H3, but not by H1 agonists.

  8. Facile preparation of biphasic-induced magnetic icariin-loaded composite microcapsules by automated in situ click technology.

    PubMed

    Pan, Panpan; Chen, Jingdi; Fan, Tiantang; Hu, Yimin; Wu, Tao; Zhang, Qiqing

    2016-04-01

    This research aims to prepare the biphasic-induced magnetic composite microcapsules (BIMCM) as a promising environmental stimuli-responsive delivery vehicle to dispose the problem of drug burst effect. The paper presented a novel automated in situ click technology of magnetic chitosan/nano hydroxyapatite (CS/nHA) microcapsules. Fe3O4 magnetic nanoparticles (MNP) and nHA were simultaneously in situ crystallized by one-step process. Icariin (ICA), a plant-derived flavonol glycoside, was combined to study drug release properties of BIMCM. BIMCM were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Thermal gravimetric analysis/Differential Scanning Calorimetry(TGA/DSC) in order to reveal their component and surface morphology as well as the role of the in situ generated Fe3O4 MNP and nHA. The magnetic test showed the BIMCM were super-paramagnetic. Both in situ generated Fe3O4 MNP and nHA serve as stable inorganic crosslinkers in BIMCM to form many intermolecular crosslinkages for the movability of the CS chains. This makes ICA loaded microcapsules take on a sustained release behavior and results in the self-adjusting of surface morphology, decreasing of swelling and degradation rates. In addition, in vitro tests were systematically carried out to examine the biocompatibility of the microcapsules by MTT test, Wright-Giemsa dying assay and AO/EB fluorescent staining method. These results demonstrated that successful introduction of the in situ click Fe3O4 MNP provided an alternative strategy because of magnetic sensitivity and sustained release. As such, the novel ICA loaded biphasic-induced magnetic CS/nHA/MNP microcapsules are expected to find potential applications in drug delivery system for bone repair. PMID:26735894

  9. Imitators of exercise-induced bronchoconstriction

    PubMed Central

    2009-01-01

    Exercise-induced bronchoconstriction (EIB) is described by transient narrowing of the airways after exercise. It occurs in approximately 10% of the general population, while athletes may show a higher prevalence, especially in cold weather and ice rink athletes. Diagnosis of EIB is often made on the basis of self-reported symptoms without objective lung function tests, however, the presence of EIB can not be accurately determined on the basis of symptoms and may be under-, over-, or misdiagnosed. The goal of this review is to describe other clinical entities that mimic asthma or EIB symptoms and can be confused with EIB. PMID:20016690

  10. Update on exercise-induced asthma.

    PubMed

    Spector, S L

    1993-12-01

    Exercise-induced asthma (EIA) is a temporary increase in airway resistance that occurs after several minutes of strenuous exercise, generally eight to 15 minutes after the patient has stopped exercising. Some individuals experience a secondary reduction in pulmonary function several hours later, the so-called late-phase response. Many physicians believe that EIA is caused by respiratory water loss or airway cooling. Others incriminate tissue mast cells of the lung. The role of histamine is uncertain because it is detected inconsistently in the serum after an attack. Recent studies suggest that the release of sulfidopeptide leukotrienes may play a major role in EIA. Although the exact pathophysiology has yet to be determined, several highly successful treatment regimens have been developed. Preventive pharmacologic treatment with aerosolized beta-agonists is more successful than treatment with cromolyn sodium; however, coadministration of these agents produces significant symptomatic improvement in more than 90% of patients. Other useful medications include antihistamines, anticholinergic agents, theophylline, oral beta-agonists, calcium channel blockers, alpha-adrenergic antagonists, nedocromil, and leukotriene antagonists. Exercise-induced asthma may be suppressed with warm humidified air. This environment can be simulated by swimming in a heated pool or wearing a scarf over the nose and mouth in cold weather. PMID:8267254

  11. Exercise-induced anaphylaxis: A clinical view

    PubMed Central

    2012-01-01

    Exercise-induced anaphylaxis (EIA) is a distinct form of physical allergy. The development of anaphylaxis during exertion often requires the concomitant exposure to triggering factors such as intake of foods (food dependent exercise-induced anaphylaxis) or drugs prior to exercise, extreme environmental conditions. EIA is a rare, but serious disorder, which is often undetected or inadequately treated. This article summarizes current evidences on pathophysiology, diagnosis and management. We reviewed recent advances in factors triggering the release of mediators from mast cells which seems to play a pathogenetic role. A correct diagnosis is essential to avoid unnecessary restricted diet, to allow physical activity in subjects with EIA dependent from triggering factors such as food, and to manage attacks. An algorithm for diagnosing EIA based on medical history, IgE tests and exercise challenge test has been provided. In the long-term management of EIA, there is a need for educating patients and care-givers to avoid exposure to precipitating factors and to recognize and treat episodes. Future researches on existing questions are discussed. PMID:22980517

  12. [Exercise-induced bronchospasm. Diagnosis and management].

    PubMed

    Rosas Miguel, A; Pérez, Jaime; Blandón, Virginia; del Rio, Blanca; Sienra Monge, Juan José Luis

    2004-01-01

    Exercise-induced bronchospam is a common entity in asthmatic children. Physiopathology involves airway cooling, airway dehydration and influx of inflammatory cells such as histamine or eicosanoids. Diagnosis is done by a suggestive clinical history, besides a VEF1 reversibility of 15% after the use of a beta agonist. Differential diagnosis should be done with similar presentation pathologies. Warming up routines and beta agonist should be used in regular bases as previous treatment in this kind of disease. PMID:15237914

  13. [Cereal-dependent exercise-induced anaphylaxis].

    PubMed

    Seoane-Rodríguez, Marta; Caralli, María Elisa; Morales-Cabeza, Cristina; Micozzi, Sarah; De Barrio-Fernández, Manuel; Rojas Pérez-Ezquerra, Patricia

    2016-01-01

    Wheat-dependent exercise-induced anaphylaxis (WDEIA) is increasing. In vitro test such as omega-5-gliadin levels are useful in the diagnosis, while oral single blind challenge tests (OCT) with wheat plus exercise continuous being the gold standard diagnostic method. This paper reports the case of a 38-year-old woman, with several episodes of anaphylaxis after eating different foods and doing exercise after ingestion. An allergy study was performed with positive skin prick tests for wheat, barley and rye. Total IgE 238.0KU/L, positive specific IgE (>100KU/L) to wheat, barley and rye, and negative to rTri-a-19 omega-5 gliadin. OCT with bread and exercise was positive. In this case of wheat-dependent exerciseinduced anaphylaxis (WDEIA) with negative serum specific IgE to omega-5-gliadin, negative results with gamma, alpha, bheta y omega-gliadin doesn't exclude the diagnosis of WDEIA. PMID:26943835

  14. Exercise-induced anaphylaxis related to specific foods.

    PubMed

    Tilles, S; Schocket, A; Milgrom, H

    1995-10-01

    We describe the case, documented by challenge results, of a 16-year-old girl with exercise-induced anaphylaxis associated with eating pizza and a cheese sandwich. Patients in whom a specific coprecipitating food has been identified should avoid it for at least 12 hours before exercise. All patients should be instructed to avoid eating 6 to 8 hours before exercise, discontinue exercise at the first sign of symptoms, and exercise only with a companion prepared to administer epinephrine. PMID:7562280

  15. l-cysteine reversibly inhibits glucose-induced biphasic insulin secretion and ATP production by inactivating PKM2

    PubMed Central

    Nakatsu, Daiki; Horiuchi, Yuta; Kano, Fumi; Noguchi, Yoshiyuki; Sugawara, Taichi; Takamoto, Iseki; Kubota, Naoto; Kadowaki, Takashi; Murata, Masayuki

    2015-01-01

    Increase in the concentration of plasma l-cysteine is closely associated with defective insulin secretion from pancreatic β-cells, which results in type 2 diabetes (T2D). In this study, we investigated the effects of prolonged l-cysteine treatment on glucose-stimulated insulin secretion (GSIS) from mouse insulinoma 6 (MIN6) cells and from mouse pancreatic islets, and found that the treatment reversibly inhibited glucose-induced ATP production and resulting GSIS without affecting proinsulin and insulin synthesis. Comprehensive metabolic analyses using capillary electrophoresis time-of-flight mass spectrometry showed that prolonged l-cysteine treatment decreased the levels of pyruvate and its downstream metabolites. In addition, methyl pyruvate, a membrane-permeable form of pyruvate, rescued l-cysteine–induced inhibition of GSIS. Based on these results, we found that both in vitro and in MIN6 cells, l-cysteine specifically inhibited the activity of pyruvate kinase muscle isoform 2 (PKM2), an isoform of pyruvate kinases that catalyze the conversion of phosphoenolpyruvate to pyruvate. l-cysteine also induced PKM2 subunit dissociation (tetramers to dimers/monomers) in cells, which resulted in impaired glucose-induced ATP production for GSIS. DASA-10 (NCGC00181061, a substituted N,N′-diarylsulfonamide), a specific activator for PKM2, restored the tetramer formation and the activity of PKM2, glucose-induced ATP production, and biphasic insulin secretion in l-cysteine–treated cells. Collectively, our results demonstrate that impaired insulin secretion due to exposure to l-cysteine resulted from its direct binding and inactivation of PKM2 and suggest that PKM2 is a potential therapeutic target for T2D. PMID:25713368

  16. Temperature jump induced force generation in rabbit muscle fibres gets faster with shortening and shows a biphasic dependence on velocity.

    PubMed

    Ranatunga, K W; Roots, H; Offer, G W

    2010-02-01

    We examined the tension responses to ramp shortening and rapid temperature jump (<0.2 ms, 3-4 degrees C T-jump) in maximally Ca(2+)-activated rabbit psoas muscle fibres at 8-9 degrees C (the fibre length (L(0)) was approximately 1.5 mm and sarcomere length 2.5 microm). The aim was to investigate the strain sensitivity of crossbridge force generation in muscle. The T-jump induced tension rise was examined during steady shortening over a wide range of velocities (V) approaching the V(max) (V range approximately 0.01 to approximately 1.5 L(0) s(1)). In the isometric state, a T-jump induced a biphasic tension rise consisting of a fast (approximately 50 s(1), phase 2b) and a slow (approximately 10 s(1), phase 3) component, but if treated as monophasic the rate was approximately 20 s(1). During steady shortening the T-jump tension rise was monophasic; the rate of tension rise increased linearly with shortening velocity, and near V(max) it was approximately 200 s(1), approximately 10x faster than in the isometric state. Relative to the tension reached after the T-jump, the amplitude increased with shortening velocity, and near V(max) it was 4x larger than in the isometric state. Thus, the temperature sensitivity of muscle force is markedly increased with velocity during steady shortening, as found in steady state experiments. The rate of tension decline during ramp shortening also increased markedly with increase of velocity. The absolute amplitude of T-jump tension rise was larger than that in the isometric state at the low velocities (<0.5 L(0) s(1)) but decreased to below that of the isometric state at the higher velocities. Such a biphasic velocity dependence of the absolute amplitude of T-jump tension rise implies interplay between, at least, two processes that have opposing effects on the tension output as the shortening velocity is increased, probably enhancement of crossbridge force generation and faster (post-stroke) crossbridge detachment by negative strain

  17. Temperature jump induced force generation in rabbit muscle fibres gets faster with shortening and shows a biphasic dependence on velocity

    PubMed Central

    Ranatunga, K W; Roots, H; Offer, G W

    2010-01-01

    We examined the tension responses to ramp shortening and rapid temperature jump (<0.2 ms, 3–4°C T-jump) in maximally Ca2+-activated rabbit psoas muscle fibres at 8–9°C (the fibre length (L0) was ∼1.5 mm and sarcomere length 2.5 μm). The aim was to investigate the strain sensitivity of crossbridge force generation in muscle. The T-jump induced tension rise was examined during steady shortening over a wide range of velocities (V) approaching the Vmax (V range ∼0.01 to ∼1.5 L0 s−1). In the isometric state, a T-jump induced a biphasic tension rise consisting of a fast (∼50 s−1, phase 2b) and a slow (∼10 s−1, phase 3) component, but if treated as monophasic the rate was ∼20 s−1. During steady shortening the T-jump tension rise was monophasic; the rate of tension rise increased linearly with shortening velocity, and near Vmax it was ∼200 s−1, ∼10× faster than in the isometric state. Relative to the tension reached after the T-jump, the amplitude increased with shortening velocity, and near Vmax it was ∼4× larger than in the isometric state. Thus, the temperature sensitivity of muscle force is markedly increased with velocity during steady shortening, as found in steady state experiments. The rate of tension decline during ramp shortening also increased markedly with increase of velocity. The absolute amplitude of T-jump tension rise was larger than that in the isometric state at the low velocities (<0.5 L0 s−1) but decreased to below that of the isometric state at the higher velocities. Such a biphasic velocity dependence of the absolute amplitude of T-jump tension rise implies interplay between, at least, two processes that have opposing effects on the tension output as the shortening velocity is increased, probably enhancement of crossbridge force generation and faster (post-stroke) crossbridge detachment by negative strain. Overall, our results show that T-jump force generation is strain sensitive and becomes considerably faster

  18. Mycobacterium terrae isolated from indoor air of a moisture-damaged building induces sustained biphasic inflammatory response in mouse lungs.

    PubMed Central

    Jussila, Juha; Komulainen, Hannu; Huttunen, Kati; Roponen, Marjut; Iivanainen, Eila; Torkko, Pirjo; Kosma, Veli-Matti; Pelkonen, Jukka; Hirvonen, Maija-Riitta

    2002-01-01

    Occupants in moisture-damaged buildings suffer frequently from respiratory symptoms. This may be partly due to the presence of abnormal microbial growth or the altered microbial flora in the damaged buildings. However, the specific effects of the microbes on respiratory health and the way they provoke clinical manifestations are poorly understood. In the present study, we exposed mice via intratracheal instillation to a single dose of Mycobacterium terrae isolated from the indoor air of a moisture-damaged building (1 X 10(7), 5 X 10(7), or 1 X 10(8) microbes). Inflammation and toxicity in lungs were evaluated 2 hr later. The time course of the effects was assessed with the dose of 1 X 10(8) bacterial cells for up to 28 days. M. terrae caused a sustained biphasic inflammation in mouse lungs. The characteristic features for the first phase, which lasted from 6 hr to 3 days, were elevated proinflammatory cytokine [i.e., tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6)] levels in the bronchoalveolar lavage fluid (BALF). TNF-alpha was produced in the lungs more intensively than was IL-6. Neutrophils were the most abundant cells in the airways during the first phase, although their numbers in BALF remained elevated up to 21 days. The characteristics of the second phase, which lasted from 7 to 28 days, were elevated TNF-alpha levels in BALF, expression of inducible nitric oxide synthase in BAL cells, and recruitment of mononuclear cells such as lymphocytes and macrophages into the airways. Moreover, total protein, albumin, and lactate dehydrogenase concentrations were elevated in both phases in BALF. The bacteria were detected in lungs up to 28 days. In summary, these observations indicate that M. terrae is capable of provoking a sustained, biphasic inflammation in mouse lungs and can cause a moderate degree of cytotoxicity. Thus, M. terrae can be considered a species with potential to adversely affect the health of the occupants of moisture

  19. Exercise-induced bronchospasm - pathophysiology and treatment.

    PubMed

    Shephard, R J

    1981-09-01

    The practical importance, prevalence, typical features, physiopathology and therapy of exercise-induced bronchospasm (E.I.B.) are briefly reviewed. The condition is common, especially in children. Prevalence is influenced by the mode, intensity and duration of exercise, the age and possibly the sex of the subjects, the number of test repetitions, and the criterion for presence of spasm. The main site of obstruction is in the large airways. Symptoms appear a few minutes post-effort, peaking 10-15 minutes after exercise. At different times, spasm may arise in the vagal reflex arc, from alterations of sympathetic balance, prostaglandin release, and sensitization of the mast cell. Until recently, the main basis of prophylaxis has been inhalation of sodium cromoglycate (20 mg, 60 minutes prior to competition). Beta agonists have until recently been prohibited in international competitions. However, the use of selective beta agonists such as salbutamol and terbutaline was allowed in the 1978 World Swimming Championship and the 1980 World Cross-Country Championship with a supporting medical letter. The Medical Commission of the International Olympic Committee has also moved recently to sanction the use of salbutamol and terbutaline. Future prophylaxis will thus be based on combinations of selective beta agonists and sodium cromoglycate. PMID:6794921

  20. Update on exercise-induced pulmonary hemorrhage.

    PubMed

    Sullivan, Stacey; Hinchcliff, Kenneth

    2015-04-01

    Exercise-induced pulmonary hemorrhage (EIPH) is an important disease of horses that perform high-intensity athletic activity. EIPH is an ongoing concern for the racing industry because of its high prevalence; potential impact on performance; welfare concerns; and use of prophylactic medications, such as furosemide, on race day. During the last 10 years, significant progress has been made in understanding the pathogenesis and risk factors for EIPH and the impact of the disease on performance and career. This article summarizes the most recent advances in EIPH. PMID:25770069

  1. Astragalus membranaceus improves exercise performance and ameliorates exercise-induced fatigue in trained mice.

    PubMed

    Yeh, Tzu-Shao; Chuang, Hsiao-Li; Huang, Wen-Ching; Chen, Yi-Ming; Huang, Chi-Chang; Hsu, Mei-Chich

    2014-01-01

    Astragalus membranaceus (AM) is a popular "Qi-tonifying" herb with a long history of use as a Traditional Chinese Medicine with multiple biological functions. However, evidence for the effects of AM on exercise performance and physical fatigue is limited. We evaluated the potential beneficial effects of AM on ergogenic and anti-fatigue functions following physiological challenge. Male ICR strain mice were randomly assigned to four groups (n = 10 per group) for treatment: (1) sedentary control and vehicle treatment (vehicle control); (2) exercise training with vehicle treatment (exercise control); and (3) exercise training with AM treatment at 0.615 g/kg/day (Ex-AM1) or (4) 3.075 g/kg/day (Ex-AM5). Both the vehicle and AM were orally administered for 6 weeks. Exercise performance and anti-fatigue function were evaluated by forelimb grip strength, exhaustive swimming time, and levels of serum lactate, ammonia, glucose, and creatine kinase after 15-min swimming exercise. Exercise training combined with AM supplementation increased endurance exercise capacity and increased hepatic and muscle glycogen content. AM reduced exercise-induced accumulation of the byproducts blood lactate and ammonia with acute exercise challenge. Moreover, we found no deleterious effects from AM treatment. Therefore, AM supplementation improved exercise performance and had anti-fatigue effects in mice. It may be an effective ergogenic aid in exercise training. PMID:24595275

  2. Low-Intensity Repetitive Exercise Induced Rhabdomyolysis

    PubMed Central

    Tran, Mina; Hayden, Nicholas; Garcia, Brandon; Tucci, Veronica

    2015-01-01

    Rhabdomyolysis is a rare condition caused by the proteins of damaged muscle cells entering the bloodstream and damaging the kidneys. Common symptoms of rhabdomyolysis are muscle pain and fatigue in conjunction with dark urine; kidney damage is a common symptom among these patients. We present a case of a 23-year-old woman who displayed myalgia in the upper extremities caused by low-intensity and high-repetition exercise. She was successfully diagnosed and treated for exertional rhabdomyolysis. This patient had no significant medical history that would induce this condition. We urge the emergency medical community to observe and monitor patients that complain of myalgia to ensure they are not suffering from rhabdomyolysis even in atypical cases. PMID:26693360

  3. Exercise excess pressure and exercise-induced albuminuria in patients with type 2 diabetes mellitus.

    PubMed

    Climie, Rachel E D; Srikanth, Velandai; Keith, Laura J; Davies, Justin E; Sharman, James E

    2015-05-01

    Exercise-induced albuminuria is common in patients with type 2 diabetes mellitus (T2DM) in response to maximal exercise, but the response to light-moderate exercise is unclear. Patients with T2DM have abnormal central hemodynamics and greater propensity for exercise hypertension. This study sought to determine the relationship between light-moderate exercise central hemodynamics (including aortic reservoir and excess pressure) and exercise-induced albuminuria. Thirty-nine T2DM (62 ± 9 yr; 49% male) and 39 nondiabetic controls (53 ± 9 yr; 51% male) were examined at rest and during 20 min of light-moderate cycle exercise (30 W; 50 revolutions/min). Albuminuria was assessed by the albumin-creatinine ratio (ACR) at rest and 30 min postexercise. Hemodynamics recorded included brachial and central blood pressure (BP), aortic stiffness, augmented pressure (AP), aortic reservoir pressure, and excess pressure integral (Pexcess). There was no difference in ACR between groups before exercise (P > 0.05). Exercise induced a significant rise in ACR in T2DM but not controls (1.73 ± 1.43 vs. 0.53 ± 1.0 mg/mol, P = 0.002). All central hemodynamic variables were significantly higher during exercise in T2DM (i.e., Pexcess, systolic BP and AP; P < 0.01 all). In T2DM (but not controls), exercise Pexcess was associated with postexercise ACR (r = 0.51, P = 0.002), and this relationship was independent of age, sex, body mass index, heart rate, aortic stiffness, antihypertensive medication, and ambulatory daytime systolic BP (β = 0.003, P = 0.003). Light-moderate exercise induced a significant rise in ACR in T2DM, and this was independently associated with Pexcess, a potential marker of vascular dysfunction. These novel findings suggest that Pexcess could be important for appropriate renal function in T2DM. PMID:25724495

  4. Exercise Challenge for Exercise-Induced Bronchospasm. Confirming Presence, Evaluating Control.

    ERIC Educational Resources Information Center

    Kaplan, Ted A.

    1995-01-01

    Exercise-induced bronchospasm commonly strikes young people, keeping many away from activity. The exercise challenge test (a powerful tool in diagnosing the condition, fine-tuning treatment, and improving patient compliance) can help get patients back in action. Knowing how to interpret and use test results helps physicians expedite effective…

  5. Memory of pain induced by physical exercise.

    PubMed

    Bąbel, Przemysław

    2016-04-01

    The aim of this study was to assess the memory of pain induced by running a marathon and the factors that influence it. Sixty-two marathon runners participated in the study, which comprised two phases. Immediately after a participant had reached the finishing line of the marathon, they were asked to rate the intensity and the unpleasantness of their pain and the emotions they felt at that time. Either three or six months later they were asked again to rate the intensity and the unpleasantness of the same pain experience. Regardless of the length of recall delay, participants underestimated both recalled pain intensity and unpleasantness. The pain and negative affect reported at the time of the pain experience accounted for 24% of the total variance in predicting recalled pain intensity and 22% of the total variance in predicting recalled pain unpleasantness. Positive affect at the time of pain experience was not a significant predictor of both the recalled pain intensity and pain unpleasantness. It is concluded that pain induced by physical exercise is not remembered accurately and the pain and negative affect experienced influence recall. Further research is needed on the influence of positive affect on the memory of pain. PMID:25806782

  6. Personality Does not Influence Exercise-Induced Mood Enhancement Among Female Exercisers.

    PubMed

    Lane, Andrew M; Milton, Karen E; Terry, Peter C

    2005-09-01

    The present study investigated the influence of personality on exercise-induced mood changes. It was hypothesised that (a) exercise would be associated with significant mood enhancement across all personality types, (b) extroversion would be associated with positive mood and neuroticism with negative mood both pre- and post-exercise, and (c) personality measures would interact with exercise-induced mood changes. Participants were 90 female exercisers (M = 25.8 yr, SD = 9.0 yr) who completed the Eysenck Personality Inventory (EPI) once and the Brunel Mood Scale (BRUMS) before and after a 60-minute exercise session. Median splits were used to group participants into four personality types: stable introverts (n = 25), stable extroverts (n = 20), neurotic introverts (n = 26), and neurotic extroverts (n = 19). Repeated measures MANOVA showed significant mood enhancement following exercise across all personality types. Neuroticism was associated with negative mood scores pre- and post-exercise but the effect of extroversion on reported mood was relatively weak. There was no significant interaction effect between exercise-induced mood enhancement and personality. In conclusion, findings lend support to the notion that exercise is associated with improved mood. However, findings show that personality did not influence this effect, although neuroticism was associated with negative mood. Key PointsResearch in general psychology has found that stable personality trait are associated changes in mood states. Ninety females exercisers completed a personality test and mood scales before and after exercise. Results indicated mood changes were not associated with personality, although neuroticism was associated with negative mood. PMID:24453525

  7. Clinical application of neuromuscular electrical stimulation induced cardiovascular exercise.

    PubMed

    Caulfield, Brian; Crowe, Louis; Coughlan, Garrett; Minogue, Conor

    2011-01-01

    We need to find novel ways of increasing exercise participation, particularly in those populations who find it difficult to participate in voluntary exercise. In recent years researchers have started to investigate the potential for using electrical stimulation to artificially stimulate a pattern of muscle activity that would induce a physiological response consistent with cardiovascular exercise. Work to date has indicated that this is best achieved by using a stimulation protocol that results in rapid rhythmical isometric contractions of the large leg muscle groups at sub tetanic frequencies. Studies completed by our group indicate that this technique can serve as a viable alternative to voluntary cardiovascular exercise. Apart from being able to induce a cardiovascular exercise effect in patient populations (e.g. heart failure, COPD, spinal cord injury, obesity), this approach may also have value in promotion of exercise activity in a microgravity environment. PMID:22255036

  8. Exercise-induced bronchoconstriction in Tunisian elite athletes is underdiagnosed

    PubMed Central

    Sallaoui, Ridha; Zendah², Ines; Ghedira², Habib; Belhaouz³, Mohcine; Ghrairi³, Mourad; Amri³, Mohamed

    2011-01-01

    Many studies have shown an increased risk of developing exercise-induced bronchoconstriction among the athletic population, particularly at the elite level. Subjective methods for assessing exercise-induced bronchoconstriction such as surveys and questionnaires have been used but have resulted in an underestimation of the prevalence of airway dysfunction when compared with objective measurements. The aim of the present study was to compare the prevalence of exercise-induced bronchoconstriction among Tunisian elite athletes obtained using an objective method with that using a subjective method, and to discuss the possible causes and implications of the observed discrepancy. As the objective method we used spirometry before and after exercise and for the subjective approach we used a medical history questionnaire. All of the recruited 107 elite athletes responded to the questionnaire about respiratory symptoms and medical history and underwent a resting spirometry testing before and after exercise. Post-exercise spirometry revealed the presence of exercise-induced bronchoconstriction in 14 (13%) of the elite athletes, while only 1.8% reported having previously been diagnosed with asthma. In conclusion, our findings indicate that medical history-based diagnoses of exercise-induced bronchoconstriction lead to underestimations of true sufferers. PMID:24198569

  9. Exercise-induced stress resistance is independent of exercise controllability and the medial prefrontal cortex.

    PubMed

    Greenwood, Benjamin N; Spence, Katie G; Crevling, Danielle M; Clark, Peter J; Craig, Wendy C; Fleshner, Monika

    2013-02-01

    Exercise increases resistance against stress-related disorders such as anxiety and depression. Similarly, the perception of control is a powerful predictor of neurochemical and behavioral responses to stress, but whether the experience of choosing to exercise, and exerting control over that exercise, is a critical factor in producing exercise-induced stress resistance is unknown. The current studies investigated whether the protective effects of exercise against the anxiety- and depression-like consequences of stress are dependent on exercise controllability and a brain region implicated in the protective effects of controllable experiences, the medial prefrontal cortex. Adult male Fischer 344 rats remained sedentary, were forced to run on treadmills or motorised running wheels, or had voluntary access to wheels for 6 weeks. Three weeks after exercise onset, rats received sham surgery or excitotoxic lesions of the medial prefrontal cortex. Rats were exposed to home cage or uncontrollable tail shock treatment three weeks later. Shock-elicited fear conditioning and shuttle box escape testing occurred the next day. Both forced and voluntary wheel running, but not treadmill training, prevented the exaggerated fear conditioning and interference with escape learning produced by uncontrollable stress. Lesions of the medial prefrontal cortex failed to eliminate the protective effects of forced or voluntary wheel running. These data suggest that exercise controllability and the medial prefrontal cortex are not critical factors in conferring the protective effects of exercise against the affective consequences of stressor exposure, and imply that exercise perceived as forced may still benefit affect and mental health. PMID:23121339

  10. Exercise-induced asthma. What family physicians should do.

    PubMed Central

    D'Urzo, A.

    1995-01-01

    Exercise-induced asthma is described as a transitory increase in airway resistance during or after vigorous exercise. Nearly 90% of patients with chronic asthma and 40% of allergic nonasthmatic patients have the condition. Family physicians should try to educate patients about their asthma and, barring contraindications, encourage them to participate in regular physical activity. PMID:8563507

  11. Exercise induces mitochondrial biogenesis after brain ischemia in rats.

    PubMed

    Zhang, Q; Wu, Y; Zhang, P; Sha, H; Jia, J; Hu, Y; Zhu, J

    2012-03-15

    Stroke is a major cause of death worldwide. Previous studies have suggested both exercise and mitochondrial biogenesis contribute to improved post-ischemic recovery of brain function. However, the exact mechanism underlying this effect is unclear. On the other hand, the benefit of exercise-induced mitochondrial biogenesis in brain has been confirmed. In this study, we attempted to determine whether treadmill exercise induces functional improvement through regulation of mitochondrial biogenesis after brain ischemia. We subjected adult male rats to ischemia, followed by either treadmill exercise or non-exercise and analyzed the effect of exercise on the amount of mitochondrial DNA (mtDNA), expression of mitochondrial biogenesis factors, and mitochondrial protein. In the ischemia-exercise group, only peroxisome proliferator activated receptor coactivator-1 (PGC-1) expression was increased significantly after 3 days of treadmill training. However, after 7 days of training, the levels of mtDNA, nuclear respiratory factor 1, NRF-1, mitochondrial transcription factor A, TFAM, and the mitochondrial protein cytochrome C oxidase subunit IV (COXIV) and heat shock protein-60 (HSP60) also increased above levels observed in non-exercised ischemic animals. These changes followed with significant changes in behavioral scores and cerebral infarct volume. The results indicate that exercise can promote mitochondrial biogenesis after ischemic injury, which may serve as a novel component of exercise-induced repair mechanisms of the brain. Understanding the molecular basis for exercise-induced neuroprotection may be beneficial in the development of therapeutic approaches for brain recovery from the ischemic injury. Based upon our findings, stimulation or enhancement of mitochondrial biogenesis may prove a novel neuroprotective strategy in the future. PMID:22266265

  12. Polyphenols in Exercise Performance and Prevention of Exercise-Induced Muscle Damage

    PubMed Central

    Hrelia, Silvana

    2013-01-01

    Although moderate physical exercise is considered an essential component of a healthy lifestyle that leads the organism to adapt itself to different stresses, exercise, especially when exhaustive, is also known to induce oxidative stress, inflammation, and muscle damage. Many efforts have been carried out to identify dietary strategies or micronutrients able to prevent or at least attenuate the exercise-induced muscle damage and stress. Unfortunately most studies have failed to show protection, and at the present time data supporting the protective effect of micronutrients, as antioxidant vitamins, are weak and trivial. This review focuses on those polyphenols, present in the plant kingdom, that have been recently suggested to exert some positive effects on exercise-induced muscle damage and oxidative stress. In the last decade flavonoids as quercetin, catechins, and other polyphenols as resveratrol have caught the scientists attention. However, at the present time drawing a clear and definitive conclusion seems to be untimely. PMID:23983900

  13. In vivo indomethacin reverse exercise-induced immunosuppression in rats.

    PubMed

    Asselin, P; Benquet, C; Krzystyniak, K; Brousseau, P; Savard, R; Fournier, M

    1996-01-01

    The effect of oral indomethacin on the immunosuppressive effect of exercise was examined in exercised untrained female Wistar rats immunized with sheep red blood cell (SRBC) antigens. Intensity of the 1 h exercise was controlled by 0-50 kPa air pressure, generated by a compressor located at the bottom of a water tank, during continuous swimming of the rats, previously immunized with SRBC. After 48-72 h, depending on the ip (intraperitoneal) or iv (intravenous) route of SRBC immunization, the exercise suppressed humoral PFC response and augmented phagocytosis of peritoneum macrophages. These effects occurred only when exercise was performed at 48 h after antigen injection. Animals receiving indomethacin, however, did not show any exercise-related suppression of the PFC response. The data suggest a relationship between exercise-induced immunosuppression and possible increased in vivo prostaglandin synthesis during the intense exercise. Overall, exercise-related suppression of humoral PFC response was dependent on the intensity of the exercise, was time specific, and was reversible by pharmacological blockade of the cyclooxygenase pathway of prostaglandin synthesis. PMID:9023588

  14. Exercise-induced hypoalgesia - interval versus continuous mode.

    PubMed

    Kodesh, Einat; Weissman-Fogel, Irit

    2014-07-01

    Aerobic exercise at approximately 70% of maximal aerobic capacity moderately reduces pain sensitivity and attenuates pain, even after a single session. If the analgesic effects depend on exercise intensity, then high-intensity interval exercise at 85% of maximal aerobic capacity should further reduce pain. The aim of this study was to explore the exercise-induced analgesic effects of high-intensity interval aerobic exercise and to compare them with the analgesic effects of moderate continuous aerobic exercise. Twenty-nine young untrained healthy males were randomly assigned to aerobic-continuous (70% heart rate reserve (HRR)) and interval (4 × 4 min at 85% HRR and 2 min at 60% HRR between cycles) exercise modes, each lasting 30 min. Psychophysical pain tests, pressure and heat pain thresholds (HPT), and tonic heat pain (THP) were conducted before and after exercise sessions. Repeated measures ANOVA was used for data analysis. HPT increased (p = 0.056) and THP decreased (p = 0.013) following exercise unrelated to exercise type. However, the main time effect (pre-/postexercise) was a trend of increased HPT (45.6 ± 1.9 °C to 46.2 ± 1.8 °C; p = 0.082) and a significant reduction in THP (from 50.7 ± 25 to 45.9 ± 25.4 numeric pain scale; p = 0.043) following interval exercise. No significant change was found for the pressure pain threshold following either exercise type. In conclusion, interval exercise (85% HRR) has analgesic effects on experimental pain perception. This, in addition to its cardiovascular, muscular, and metabolic advantages may promote its inclusion in pain management programs. PMID:24773287

  15. Treadmill exercise induces hippocampal astroglial alterations in rats.

    PubMed

    Bernardi, Caren; Tramontina, Ana Carolina; Nardin, Patrícia; Biasibetti, Regina; Costa, Ana Paula; Vizueti, Adriana Fernanda; Batassini, Cristiane; Tortorelli, Lucas Silva; Wartchow, Krista Minéia; Dutra, Márcio Ferreira; Bobermin, Larissa; Sesterheim, Patrícia; Quincozes-Santos, André; de Souza, Jaqueline; Gonçalves, Carlos Alberto

    2013-01-01

    Physical exercise effects on brain health and cognitive performance have been described. Synaptic remodeling in hippocampus induced by physical exercise has been described in animal models, but the underlying mechanisms remain poorly understood. Changes in astrocytes, the glial cells involved in synaptic remodeling, need more characterization. We investigated the effect of moderate treadmill exercise (20 min/day) for 4 weeks on some parameters of astrocytic activity in rat hippocampal slices, namely, glial fibrillary acidic protein (GFAP), glutamate uptake and glutamine synthetase (GS) activities, glutathione content, and S100B protein content and secretion, as well as brain-derived neurotrophic factor (BDNF) levels and glucose uptake activity in this tissue. Results show that moderate treadmill exercise was able to induce a decrease in GFAP content (evaluated by ELISA and immunohistochemistry) and an increase in GS activity. These changes could be mediated by corticosterone, whose levels were elevated in serum. BDNF, another putative mediator, was not altered in hippocampal tissue. Moreover, treadmill exercise caused a decrease in NO content. Our data indicate specific changes in astrocyte markers induced by physical exercise, the importance of studying astrocytes for understanding brain plasticity, as well as reinforce the relevance of physical exercise as a neuroprotective strategy. PMID:23401802

  16. Treadmill Exercise Induces Hippocampal Astroglial Alterations in Rats

    PubMed Central

    Bernardi, Caren; Tramontina, Ana Carolina; Nardin, Patrícia; Biasibetti, Regina; Costa, Ana Paula; Vizueti, Adriana Fernanda; Batassini, Cristiane; Tortorelli, Lucas Silva; Wartchow, Krista Minéia; Dutra, Márcio Ferreira; Bobermin, Larissa; Sesterheim, Patrícia; Quincozes-Santos, André; de Souza, Jaqueline; Gonçalves, Carlos Alberto

    2013-01-01

    Physical exercise effects on brain health and cognitive performance have been described. Synaptic remodeling in hippocampus induced by physical exercise has been described in animal models, but the underlying mechanisms remain poorly understood. Changes in astrocytes, the glial cells involved in synaptic remodeling, need more characterization. We investigated the effect of moderate treadmill exercise (20 min/day) for 4 weeks on some parameters of astrocytic activity in rat hippocampal slices, namely, glial fibrillary acidic protein (GFAP), glutamate uptake and glutamine synthetase (GS) activities, glutathione content, and S100B protein content and secretion, as well as brain-derived neurotrophic factor (BDNF) levels and glucose uptake activity in this tissue. Results show that moderate treadmill exercise was able to induce a decrease in GFAP content (evaluated by ELISA and immunohistochemistry) and an increase in GS activity. These changes could be mediated by corticosterone, whose levels were elevated in serum. BDNF, another putative mediator, was not altered in hippocampal tissue. Moreover, treadmill exercise caused a decrease in NO content. Our data indicate specific changes in astrocyte markers induced by physical exercise, the importance of studying astrocytes for understanding brain plasticity, as well as reinforce the relevance of physical exercise as a neuroprotective strategy. PMID:23401802

  17. Exercise-induced mitochondrial dysfunction: a myth or reality?

    PubMed

    Ostojic, Sergej M

    2016-08-01

    Beneficial effects of physical activity on mitochondrial health are well substantiated in the scientific literature, with regular exercise improving mitochondrial quality and quantity in normal healthy population, and in cardiometabolic and neurodegenerative disorders and aging. However, several recent studies questioned this paradigm, suggesting that extremely heavy or exhaustive exercise fosters mitochondrial disturbances that could permanently damage its function in health and disease. Exercise-induced mitochondrial dysfunction (EIMD) might be a key proxy for negative outcomes of exhaustive exercise, being a pathophysiological substrate of heart abnormalities, chronic fatigue syndrome (CFS) or muscle degeneration. Here, we overview possible factors that mediate negative effects of exhaustive exercise on mitochondrial function and structure, and put forward alternative solutions for the management of EIMD. PMID:27389587

  18. Circulating androgens in women: exercise-induced changes.

    PubMed

    Enea, Carina; Boisseau, Nathalie; Fargeas-Gluck, Marie Agnès; Diaz, Véronique; Dugué, Benoit

    2011-01-01

    Physical exercise is known to strongly stimulate the endocrine system in both sexes. Among these hormones, androgens (e.g. testosterone, androstenedione, dehydroepiandrosterone) play key roles in the reproductive system, muscle growth and the prevention of bone loss. In female athletes, excessive physical exercise may lead to disorders, including delay in the onset of puberty, amenorrhoea and premature osteoporosis. The free and total fractions of circulating androgens vary in response to acute and chronic exercise/training (depending on the type), but the physiological role of these changes is not completely understood. Although it is commonly accepted that only the free fraction of steroids has a biological action, this hypothesis has recently been challenged. Indeed, a change in the total fraction of androgen concentration may have a significant impact on cells (inducing genomic or non-genomic signalling). The purpose of this review, therefore, is to visit the exercise-induced changes in androgen concentrations and emphasize their potential effects on female physiology. Despite some discrepancies in the published studies (generally due to differences in the types and intensities of the exercises studied, in the hormonal status of the group of women investigated and in the methods for androgen determination), exercise is globally able to induce an increase in circulating androgens. This can be observed after both resistance and endurance acute exercises. For chronic exercise/training, the picture is definitely less clear and there are even circumstances where exercise leads to a decrease of circulating androgens. We suggest that those changes have significant impact on female physiology and physical performance. PMID:21142281

  19. The Curious Question of Exercise-Induced Pulmonary Edema

    PubMed Central

    Bates, Melissa L.; Farrell, Emily T.; Eldridge, Marlowe W.

    2011-01-01

    The question of whether pulmonary edema develops during exercise on land is controversial. Yet, the development of pulmonary edema during swimming and diving is well established. This paper addresses the current controversies that exist in the field of exercise-induced pulmonary edema on land and with water immersion. It also discusses the mechanisms by which pulmonary edema can develop during land exercise, swimming, and diving and the current gaps in knowledge that exist. Finally, this paper discusses how these fields can continue to advance and the areas where clinical knowledge is lacking. PMID:21660232

  20. Exercise effects on erythrocyte deformability in exercise-induced arterial hypoxemia.

    PubMed

    Alis, R; Sanchis-Gomar, F; Ferioli, D; La Torre, A; Blesa, J R; Romagnoli, M

    2015-04-01

    Exercise-induced arterial hypoxemia (EIAH) is often found in endurance-trained subjects at high exercise intensity. The role of erythrocyte deformability (ED) in EIAH has been scarcely explored. We aimed to explore the role of erythrocyte properties and lactate accumulation in the response of ED in EIAH. ED was determined in 10 sedentary and in 16 trained subjects, both before and after a maximal incremental test, and after recovery, along with mean corpuscular volume (MCV) and red blood cell lactate concentrations. EIAH was found in 6 trained subjects (∆SaO2=-8.25±4.03%). Sedentary and non-EIAH trained subjects showed reduced ED after exercise, while no effect on ED was found in EIAH trained subjects. After exercise, lactate concentrations rose and MCV increased equally in all groups. ED is strongly driven by cell volume, but the different ED response to exercise in EIAH shows that other cellular mechanisms may be implicated. Interactions between membrane and cytoskeleton, which have been found to be O2-regulated, play a role in ED. The drop in SaO2 in EIAH subjects can improve ED response to exercise. This can be an adaptive mechanism that enhances muscular and pulmonary perfusion, and allows the achievement of high exercise intensity in EIAH despite lower O2 arterial transport. PMID:25429547

  1. Electrocatalytic Production of C3-C4 Compounds by Conversion of CO2 on a Chloride-Induced Bi-Phasic Cu2O-Cu Catalyst.

    PubMed

    Lee, Seunghwa; Kim, Dahee; Lee, Jaeyoung

    2015-12-01

    Electrocatalytic conversion of carbon dioxide (CO2) has recently received considerable attention as one of the most feasible CO2 utilization techniques. In particular, copper and copper-derived catalysts have exhibited the ability to produce a number of organic molecules from CO2. Herein, we report a chloride (Cl)-induced bi-phasic cuprous oxide (Cu2O) and metallic copper (Cu) electrode (Cu2OCl) as an efficient catalyst for the formation of high-carbon organic molecules by CO2 conversion, and identify the origin of electroselectivity toward the formation of high-carbon organic compounds. The Cu2OCl electrocatalyst results in the preferential formation of multi-carbon fuels, including n-propanol and n-butane C3-C4 compounds. We propose that the remarkable electrocatalytic conversion behavior is due to the favorable affinity between the reaction intermediates and the catalytic surface. PMID:26473324

  2. Can Exercise Make You Smarter, Happier, and Have More Neurons? A Hormetic Perspective

    PubMed Central

    Gradari, Simona; Pallé, Anna; McGreevy, Kerry R.; Fontán-Lozano, Ángela; Trejo, José L.

    2016-01-01

    Exercise can make you smarter, happier and have more neurons depending on the dose (intensity) of the training program. It is well recognized that exercise protocols induce both positive and negative effects depending on the intensity of the exercise, among other key factors, a process described as a hormetic-like biphasic dose-response. However, no evidences have been reported till very recently about the biphasic response of some of the potential mediators of the exercise-induced actions. This hypothesis and theory will focus on the adult hippocampal neurogenesis (AHN) as a putative physical substrate for hormesis responses to exercise in the context of exercise-induced actions on cognition and mood, and on the molecular pathways which might potentially be mediating these actions. PMID:27013955

  3. Tumor necrosis factor-α induces a biphasic change in claudin-2 expression in tubular epithelial cells: role in barrier functions

    PubMed Central

    Amoozadeh, Yasaman; Dan, Qinghong; Xiao, Jenny; Waheed, Faiza

    2015-01-01

    The inflammatory cytokine tumor necrosis factor-α (TNF-α) is a pathogenic factor in acute and chronic kidney disease. TNF-α is known to alter expression of epithelial tight junction (TJ) proteins; however, the underlying mechanisms and the impact of this effect on epithelial functions remain poorly defined. Here we describe a novel biphasic effect of TNF-α on TJ protein expression. In LLC-PK1 tubular cells, short-term (1–6 h) TNF-α treatment selectively elevated the expression of the channel-forming TJ protein claudin-2. In contrast, prolonged (>8 h) TNF-α treatment caused a marked downregulation in claudin-2 and an increase in claudin-1, -4, and -7. The early increase and the late decrease in claudin-2 expression involved distinct mechanisms. TNF-α slowed claudin-2 degradation through ERK, causing the early increase. This increase was also mediated by the EGF receptor and RhoA and Rho kinase. In contrast, prolonged TNF-α treatment reduced claudin-2 mRNA levels and promoter activity independent from these signaling pathways. Electric Cell-substrate Impedance Sensing measurements revealed that TNF-α also exerted a biphasic effect on transepithelial resistance (TER) with an initial decrease and a late increase. Thus there was a good temporal correlation between TNF-α-induced claudin-2 protein and TER changes. Indeed, silencing experiments showed that the late TER increase was at least in part caused by reduced claudin-2 expression. Surprisingly, however, claudin-2 silencing did not prevent the early TER drop. Taken together, the TNF-α-induced changes in claudin-2 levels might contribute to TER changes and could also play a role in newly described functions of claudin-2 such as proliferation regulation. PMID:25948735

  4. Tumor necrosis factor-α induces a biphasic change in claudin-2 expression in tubular epithelial cells: role in barrier functions.

    PubMed

    Amoozadeh, Yasaman; Dan, Qinghong; Xiao, Jenny; Waheed, Faiza; Szászi, Katalin

    2015-07-01

    The inflammatory cytokine tumor necrosis factor-α (TNF-α) is a pathogenic factor in acute and chronic kidney disease. TNF-α is known to alter expression of epithelial tight junction (TJ) proteins; however, the underlying mechanisms and the impact of this effect on epithelial functions remain poorly defined. Here we describe a novel biphasic effect of TNF-α on TJ protein expression. In LLC-PK1 tubular cells, short-term (1-6 h) TNF-α treatment selectively elevated the expression of the channel-forming TJ protein claudin-2. In contrast, prolonged (>8 h) TNF-α treatment caused a marked downregulation in claudin-2 and an increase in claudin-1, -4, and -7. The early increase and the late decrease in claudin-2 expression involved distinct mechanisms. TNF-α slowed claudin-2 degradation through ERK, causing the early increase. This increase was also mediated by the EGF receptor and RhoA and Rho kinase. In contrast, prolonged TNF-α treatment reduced claudin-2 mRNA levels and promoter activity independent from these signaling pathways. Electric Cell-substrate Impedance Sensing measurements revealed that TNF-α also exerted a biphasic effect on transepithelial resistance (TER) with an initial decrease and a late increase. Thus there was a good temporal correlation between TNF-α-induced claudin-2 protein and TER changes. Indeed, silencing experiments showed that the late TER increase was at least in part caused by reduced claudin-2 expression. Surprisingly, however, claudin-2 silencing did not prevent the early TER drop. Taken together, the TNF-α-induced changes in claudin-2 levels might contribute to TER changes and could also play a role in newly described functions of claudin-2 such as proliferation regulation. PMID:25948735

  5. Initial Metabolic State and Exercise-Induced Endotoxaemia Are Unrelated to Gastrointestinal Symptoms During Exercise

    PubMed Central

    Moncada-Jimènez, José; Plaisance, Eric P.; Mestek, Michael L.; Araya-Ramirez, Felipe; Ratcliff, Lance; Taylor, James K.; Grandjean, Peter W.; Aragonvargas, Luis F.

    2009-01-01

    The aim of the study was to investigate the association between the initial metabolic state and exercise-induced endotoxaemia on the appearance of gastrointestinal symptoms (GIS) during exercise. Eleven males (36.6 ± 4.9 yrs, 1.7 ± 0.1 m, 74.5 ± 7.7 kg, DEXA body fat % 17.2 ± 6.6, VO2max 57.4 ± 7.4 ml·kg-1·min-1) underwent two isoenergetic diets designed to change their initial metabolic status by either depleting or maintaining their hepatic and muscular glycogen content. These diets and accompanying exercise sessions were performed by each participant in the days before completing a laboratory-based duathlon (5-km run, 30-km cycling, 10-km run). Blood samples were obtained before, immediately and 1- and 2-h following the duathlon for determination of insulin (IN), glucagon (GL), endotoxin, aspartic aminotransferase (AST), and alanine aminotransferase (ALT) markers. GIS were assessed by survey before and after exercise. Diet content produced a different energy status as determined by macronutrient content and the IN/GL ratio (p < 0.05), and mild exercise-induced endotoxaemia was observed in both experimental duathlons. Regardless of the diet, the AST/ALT ratio following exercise and in the recovery phase indicated hepatocyte and liver parenchyma structural damage. In spite of GIS, no significant correlations between endotoxin levels and GIS were found. In conclusion, increased markers of endotoxaemia observed with the high-intensity exercise were unrelated to hepatic function and/or GIS before and after exercise. Key points Gastrointestinal symptoms before, during, and after a competition are reported by approximately 20%-50% of the athletes participating in endurance events such as marathon, cycling and triathlon. Energy status, exercise-induced endotoxaemia and liver structural damage might be related to gastrointestinal symptoms. In this study, gastrointestinal symptoms observed before and after endurance exercise were unrelated to endotoxin levels or

  6. Exercise-induced asthma--clinical, physiological, and therapeutic implications.

    PubMed

    Godfrey, S

    1975-07-01

    Exercise provokes acute airways obstruction, maximum shortly after stopping, in virtually all asthmatic patients. The severity of this exercise-induced asthma (EIA) depends upon the type of exercise, with running being the most asthmogenic, swimming and walking the least, and cycling intermediate even with the same metabolic stress. The duration and severity of the exercise also affect the amount of EIA, the maximum amount of being obtained after 6 to 8 min of running hard enough to raise the heart rate to 180 beats per minute (bpm) in children or 140 bpm in adults. EIA is not the result of hyperventilation or blood gas changes and appears to depend on the release of relatively short-lived transmitter agents during the exercise period. EIA can be prevented by premedication with bronchodilators, especially with sympathomimetics. Cromolyn sodium is not a bronchodilator but inhibits EIA in most subjects if given before the exercise. EIA can also be inhibited by atropine and alpha adrenergic blockers in some patients, but by steroids in only a minority of cases. Exercise testing provides a good model for study of the physiology and pharmacology of clinical asthma, and is some guide to prognosis, but it must be properly standardized and the important differences must be appreciated. PMID:805807

  7. Exercise-Induced Syncope in a Sedentary Woman

    PubMed Central

    Rickard, John W.; Zakaria, Sammy

    2014-01-01

    Vasovagal (neurocardiogenic) syncope, a subtype of reflex syncope, has many well-known triggers. However, we found no previous report of vasovagal exercise-induced syncope in a sedentary person. We present the case of a 35-year-old sedentary woman who experienced vasovagal syncope as she underwent an exercise stress test. Results of evaluations, including resting and stress electrocardiography and echocardiography, were normal. Her presentation is highly unusual: syncope has typically not been associated with exercise except in young athletes, people with structural heart abnormalities, or people with a prolonged QT syndrome. To our knowledge, this is the first report of vasovagal syncope associated with exercise in a sedentary patient who had normal cardiac and electrophysiologic function. We suggest possible physiologic mechanisms and diagnostic strategies. PMID:25593529

  8. Exercise-induced endobronchial hemorrhage: a rare clinical presentation.

    PubMed

    Kruavit, Anuk; Jain, Mukesh; Fielding, David; Heraganahally, Subash

    2016-07-01

    The phenomenon of exercise-induced hemoptysis is still relatively underrecognised in humans. We report a case of recurrent hemoptysis brought on by vigorous exercise. A 33-year-old male presented with several episodes of intermittent fresh small-volume hemoptysis reproducible on vigorous exercise. There was no other significant medical history other than a past history of testicular tumor, treated with orchidectomy and adjuvant Bleomycin-based chemotherapy 1 year prior to onset of symptoms. Computed tomography scan showed no major abnormalities other than few small bilateral non-specific nodules. Computed tomography aortogram and pulmonary angiogram, ventilation/perfusion scan, and echocardiography yielded no significant abnormalities. Infectious, autoimmune disease, coagulopathy, vasculitis, and malignant causes were excluded. Bronchoscopy showed possible endobronchial bleeding. This phenomenon is thought to be due to vulnerability of pulmonary capillaries to stress or mechanical failure during strenuous exercise at high cardiorespiratory workload. PMID:27512564

  9. Modulating exercise-induced hormesis: Does less equal more?

    PubMed

    Peake, Jonathan M; Markworth, James F; Nosaka, Kazunori; Raastad, Truls; Wadley, Glenn D; Coffey, Vernon G

    2015-08-01

    Hormesis encompasses the notion that low levels of stress stimulate or upregulate existing cellular and molecular pathways that improve the capacity of cells and organisms to withstand greater stress. This notion underlies much of what we know about how exercise conditions the body and induces long-term adaptations. During exercise, the body is exposed to various forms of stress, including thermal, metabolic, hypoxic, oxidative, and mechanical stress. These stressors activate biochemical messengers, which in turn activate various signaling pathways that regulate gene expression and adaptive responses. Historically, antioxidant supplements, nonsteroidal anti-inflammatory drugs, and cryotherapy have been favored to attenuate or counteract exercise-induced oxidative stress and inflammation. However, reactive oxygen species and inflammatory mediators are key signaling molecules in muscle, and such strategies may mitigate adaptations to exercise. Conversely, withholding dietary carbohydrate and restricting muscle blood flow during exercise may augment adaptations to exercise. In this review article, we combine, integrate, and apply knowledge about the fundamental mechanisms of exercise adaptation. We also critically evaluate the rationale for using interventions that target these mechanisms under the overarching concept of hormesis. There is currently insufficient evidence to establish whether these treatments exert dose-dependent effects on muscle adaptation. However, there appears to be some dissociation between the biochemical/molecular effects and functional/performance outcomes of some of these treatments. Although several of these treatments influence common kinases, transcription factors, and proteins, it remains to be determined if these interventions complement or negate each other, and whether such effects are strong enough to influence adaptations to exercise. PMID:25977451

  10. Biphasic increase in scratching behaviour induced by topical application of Dermatophagoides farinae extract in NC/Nga mice.

    PubMed

    Yamada, Yoshihito; Ueda, Yuhki; Nakamura, Aki; Kanayama, Shoji; Tamura, Rie; Hashimoto, Kei; Kido, Hiroko; Matsumoto, Tatsumi; Ishii, Ritsuko

    2016-08-01

    Atopic dermatitis (AD) is a chronic inflammatory skin disease accompanied by severe itching and eczematous lesion. In this study, we applied an ointment containing Dermatophagoides farinae body (Dfb) extract repeatedly on the dorsal skin of NC/Nga mice with barrier disruption to investigate the characteristics of this murine model of human AD. Following repeated topical application of Dfb ointment twice weekly for 2 weeks, the dermatitis score increased gradually, accompanied by an elevation of total immunoglobulin E level in plasma. Topical application of Dfb ointment also caused epidermal hyperplasia and accumulation of inflammatory cells in the lesional skin and increased expression of T-helper (Th) 1/Th2/Th17 cytokines in axillary lymph node cells. Furthermore, increased sprouting of intraepidermal nerve fibres was observed with an increase in the content of nerve growth factor and decrease in that of semaphorin 3A in the lesional skin. These findings suggest that the characteristics in this model were similar to those observed in patients with AD. Interestingly, it was observed for the first time that scratching behaviour increased in a biphasic fashion by topical application of Dfb ointment in addition to an increase in spontaneous scratching behaviour in this model. It is also suggested that further clarifying the underlying mechanisms of scratching behaviour in this model leads not only to elucidating the pathogenesis of AD but also to discovering novel therapeutic drugs for AD. PMID:26990308

  11. Topical application of L-menthol induces heat analgesia, mechanical allodynia, and a biphasic effect on cold sensitivity in rats.

    PubMed

    Klein, Amanda H; Sawyer, Carolyn M; Carstens, Mirela Iodi; Tsagareli, Merab G; Tsiklauri, Nana; Carstens, E

    2010-10-15

    Menthol is used in analgesic balms and also in foods and oral hygiene products for its fresh cooling sensation. Menthol enhances cooling by interacting with the cold-sensitive thermoTRP channel TRPM8, but its effect on pain is less well understood. We presently used behavioral methods to investigate effects of topical menthol on thermal (hot and cold) pain and innocuous cold and mechanical sensitivity in rats. Menthol dose-dependently increased the latency for noxious heat-evoked withdrawal of the treated hindpaw with a weak mirror-image effect, indicating antinociception. Menthol at the highest concentration (40%) reduced mechanical withdrawal thresholds, with no effect at lower concentrations. Menthol had a biphasic effect on cold avoidance. At high concentrations (10% and 40%) menthol reduced avoidance of colder temperatures (15 degrees C and 20 degrees C) compared to 30 degrees C, while at lower concentrations (0.01-1%) menthol enhanced cold avoidance. In a -5 degrees C cold plate test, 40% menthol significantly increased the nocifensive response latency (cold hypoalgesia) while lower concentrations were not different from vehicle controls. These results are generally consistent with neurophysiological and human psychophysical data and support TRPM8 as a potential peripheral target of pain modulation. PMID:20398704

  12. mRNA Noise Reveals that Activators Induce a Biphasic Response in the Promoter Kinetics of Highly Regulated Genes

    NASA Astrophysics Data System (ADS)

    Quinn, Katie; To, Tsz-Leung; Maheshri, Narendra

    2012-02-01

    A dominant source of fluctuations in gene expression is thought to be the process of transcription. The statistics of these fluctuations arise from the kinetics of transcription. Multiple studies suggest the bulk of fluctuations can be understood by a simple process where genes are inactive for exponentially distributed times punctuated by geometric bursts of mRNA. Yet it's largely unknown how cis and trans factors affect the two lumped kinetic parameters, burst size and burst frequency, that describe this process. Importantly, how these parameters are regulated in a single gene can qualitatively affect the dynamical behavior of the network it is embedded within. Here, we ask whether transcriptional activators increase gene expression by increasing the burst size or burst frequency. We do so by deducing these parameters from steady-state mRNA distributions measured in individual yeast cells using single molecule mRNA FISH. We find that for both a synthetic and natural promoter, activators appear to first increase burst size, then burst frequency. We suggest this biphasic response may be common to all highly regulated genes and was previously unappreciated because of measurement techniques. Furthermore, its origins appear to relate to cis events at the promoter, and may arise from combinations of basal and activator-dependent bursts. Our measurements shed new light on transcriptional mechanisms and should assist in building synthetic promoters with tunable statistics.

  13. Exercise-induced oxidative stress: glutathione supplementation and deficiency.

    PubMed

    Sen, C K; Atalay, M; Hänninen, O

    1994-11-01

    Glutathione (GSH) plays a central role in coordinating the synergism between different lipid- and aqueous-phase antioxidants. We documented 1) how exogenous GSH and N-acetylcysteine (NAC) may affect exhaustive exercise-induced changes in tissue GSH status, lipid peroxides [thiobarbituric acid-reactive substances (TBARS)], and endurance and 2) the relative role of endogenous GSH in the circumvention of exercise-induced oxidative stress by using GSH-deficient [L-buthionine-(S,R)-sulfoximine (BSO)-treated] rats. Intraperitoneal injection of GSH remarkably increased plasma GSH; exogenous GSH per se was an ineffective delivery agent of GSH to tissues. Repeated administration of GSH (1 time/day for 3 days) increased blood and kidney total GSH [TGSH; GSH+oxidized GSH (GSSG)]. Neither GSH nor NAC influenced endurance to exhaustion. NAC decreased exercise-induced GSH oxidation in the lung and blood. BSO decreased TGSH pools in the liver, lung, blood, and plasma by approximately 50% and in skeletal muscle and heart by 80-90%. Compared with control, resting GSH-deficient rats had lower GSSG in the liver, red gastrocnemius muscle, heart, and blood; similar GSSG/TGSH ratios in the liver, heart, lung, blood, and plasma; higher GSSG/TGSH ratios in the skeletal muscle; and more TBARS in skeletal muscle, heart, and plasma. In contrast to control, exhaustive exercise of GSH-deficient rats did not decrease TGSH in the liver, muscle, or heart or increase TGSH of plasma; GSSG of muscle, blood, or plasma; or TBARS of plasma or muscle. GSH-deficient rats had approximately 50% reduced endurance, which suggests a critical role of endogenous GSH in the circumvention of exercise-induced oxidative stress and as a determinant of exercise performance. PMID:7868431

  14. Exercise Prevents Diet-Induced Cellular Senescence in Adipose Tissue.

    PubMed

    Schafer, Marissa J; White, Thomas A; Evans, Glenda; Tonne, Jason M; Verzosa, Grace C; Stout, Michael B; Mazula, Daniel L; Palmer, Allyson K; Baker, Darren J; Jensen, Michael D; Torbenson, Michael S; Miller, Jordan D; Ikeda, Yasuhiro; Tchkonia, Tamara; van Deursen, Jan M; Kirkland, James L; LeBrasseur, Nathan K

    2016-06-01

    Considerable evidence implicates cellular senescence in the biology of aging and chronic disease. Diet and exercise are determinants of healthy aging; however, the extent to which they affect the behavior and accretion of senescent cells within distinct tissues is not clear. Here we tested the hypothesis that exercise prevents premature senescent cell accumulation and systemic metabolic dysfunction induced by a fast-food diet (FFD). Using transgenic mice that express EGFP in response to activation of the senescence-associated p16(INK4a) promoter, we demonstrate that FFD consumption causes deleterious changes in body weight and composition as well as in measures of physical, cardiac, and metabolic health. The harmful effects of the FFD were associated with dramatic increases in several markers of senescence, including p16, EGFP, senescence-associated β-galactosidase, and the senescence-associated secretory phenotype (SASP) specifically in visceral adipose tissue. We show that exercise prevents the accumulation of senescent cells and the expression of the SASP while nullifying the damaging effects of the FFD on parameters of health. We also demonstrate that exercise initiated after long-term FFD feeding reduces senescent phenotype markers in visceral adipose tissue while attenuating physical impairments, suggesting that exercise may provide restorative benefit by mitigating accrued senescent burden. These findings highlight a novel mechanism by which exercise mediates its beneficial effects and reinforces the effect of modifiable lifestyle choices on health span. PMID:26983960

  15. Coping with Exercise-Induced Asthma in Sports.

    ERIC Educational Resources Information Center

    Katz, Roger M.

    1987-01-01

    This article reviews the history of research on exercise-induced asthma (EIA) and the pathophysiology of the condition, including its development and influencing factors. Four groups of drugs that are effective against EIA--theopyhlline, beta-adrenergic agents, cromolyn sodium, and anticholinergics--are discussed. (Author/CB)

  16. EXERCISE-INDUCED PULMONARY HEMORRHAGE AFTER RUNNING A MARATHON

    EPA Science Inventory

    We report on a healthy 26-year-old male who had an exercise-induced pulmonary hemorrhage (EIPH) within 24 hours of running a marathon. There were no symptoms, abnormalities on exam, or radiographic infiltrates. He routinely participated in bronchoscopy research and the EIPH was e...

  17. Exercise-Induced Oxidative Stress and Dietary Antioxidants

    PubMed Central

    Yavari, Abbas; Javadi, Maryam; Mirmiran, Parvin; Bahadoran, Zahra

    2015-01-01

    Context: Overproduction of reactive oxygen and nitrogen species during physical exercise, exercise induced oxidative stress and antioxidant supplementation is interesting and controversial concepts that have been considered during the past decades. Evidence Acquisition: In this review, we aimed to summarize current evidence in relation to antioxidant supplementation outcomes during exercise and physical activity. For this aim, we obtained relevant articles through searches of the Medline and PubMed databases between 1980 to 2013. Although major studies have indicated that antioxidants could attenuate biomarkers of exercise-induced oxidative stress and the use of antioxidant supplement is a common phenomenon among athletes and physically active people, there are some doubts regarding the benefits of these. Results: It seems that the best recommendations regarding antioxidants and exercise are having a balanced diet rich in natural antioxidants and phytochemicals. Conclusions: Regular consumption of various fresh fruits and vegetables, whole grains, legumes and beans, sprouts and seeds is an effective and safe way to meet all antioxidant requirements in physically active persons and athletes. PMID:25883776

  18. Identification of exercise-induced ischemia using QRS slopes.

    PubMed

    Firoozabadi, Reza; Gregg, Richard E; Babaeizadeh, Saeed

    2016-01-01

    In this work we studied a computer-aided approach using QRS slopes as unconventional ECG features to identify the exercise-induced ischemia during exercise stress testing and demonstrated that the performance is comparable to the experts' manual analysis using standard criteria involving ST-segment depression. We evaluated the performance of our algorithm using a database including 927 patients undergoing exercise stress tests and simultaneously collecting the ECG recordings and SPECT results. High resolution 12-lead ECG recordings were collected continuously throughout the rest, exercise, and recovery phases. Patients in the database were classified into three categories of moderate/severe ischemia, mild ischemia, and normal according to the differences in sum of the individual segment scores for the rest and stress SPECT images. Philips DXL 16-lead diagnostic algorithm was run on all 10-s segments of 12-lead ECG recordings for each patient to acquire the representative beats, ECG fiducial points from the representative beats, and other ECG parameters. The QRS slopes were extracted for each lead from the averaged representative beats and the leads with highest classification power were selected. We employed linear discriminant analysis and measured the performance using 10-fold cross-validation. Comparable performance of this method to the conventional ST-segment analysis exhibits the classification power of QRS slopes as unconventional ECG parameters contributing to improved identification of exercise-induced ischemia. PMID:26607407

  19. Hemoconcentration induced by exercise: Revisiting the Dill and Costill equation.

    PubMed

    Alis, R; Sanchis-Gomar, F; Primo-Carrau, C; Lozano-Calve, S; Dipalo, M; Aloe, R; Blesa, J R; Romagnoli, M; Lippi, G

    2015-12-01

    The Dill and Costill equation is used to estimate the exercise-induced hemoconcentration. However, this calculation requires drawing an extra whole-blood sample, which cannot be frozen and has to be analyzed with dedicate instrumentation in a relative short time. The aim of the present study was to explore the usefulness of some serum biochemical parameters to estimate hemoconcentration induced by exhaustive exercise. Fourteen healthy male subjects (19-34 years) performed a15-min running test at 110% of anaerobic threshold speed. Hemoglobin, hematocrit, brain natriuretic peptide (BNP), creatinine, gamma-glutamyltransferase (GGT), total-proteins, albumin, total calcium (Ca), K(+), Na(+), and Cl(-) were determined in blood samples taken before, after exercise, and after a 30-min recovery period. Plasma volume loss (ΔPV) was calculated by Dill and Costill equation. At post-exercise and after recovery, the percentage increments of total-proteins, albumin, GGT and Ca correlated significantly with ΔPV. Bland-Altman analyses showed that correcting BNP, creatinine, and K(+) concentration by Ca percentage increments yield biases and limits of agreement that are acceptable when compared with Dill and Costill equation correction. Ca concentration may be used as a hemoconcentration biomarker in high-intensity exercise, which would allow scientists and physicians avoid extra costs, facilitate in-field research, and delayed estimation of hemoconcentration using stored serum samples. PMID:25557039

  20. Air quality and temperature effects on exercise-induced bronchoconstriction.

    PubMed

    Rundell, Kenneth W; Anderson, Sandra D; Sue-Chu, Malcolm; Bougault, Valerie; Boulet, Louis-Philippe

    2015-04-01

    Exercise-induced bronchoconstriction (EIB) is exaggerated constriction of the airways usually soon after cessation of exercise. This is most often a response to airway dehydration in the presence of airway inflammation in a person with a responsive bronchial smooth muscle. Severity is related to water content of inspired air and level of ventilation achieved and sustained. Repetitive hyperpnea of dry air during training is associated with airway inflammatory changes and remodeling. A response during exercise that is related to pollution or allergen is considered EIB. Ozone and particulate matter are the most widespread pollutants of concern for the exercising population; chronic exposure can lead to new-onset asthma and EIB. Freshly generated emissions particulate matter less than 100 nm is most harmful. Evidence for acute and long-term effects from exercise while inhaling high levels of ozone and/or particulate matter exists. Much evidence supports a relationship between development of airway disorders and exercise in the chlorinated pool. Swimmers typically do not respond in the pool; however, a large percentage responds to a dry air exercise challenge. Studies support oxidative stress mediated pathology for pollutants and a more severe acute response occurs in the asthmatic. Winter sport athletes and swimmers have a higher prevalence of EIB, asthma and airway remodeling than other athletes and the general population. Because of fossil fuel powered ice resurfacers in ice rinks, ice rink athletes have shown high rates of EIB and asthma. For the athlete training in the urban environment, training during low traffic hours and in low traffic areas is suggested. PMID:25880506

  1. Exercise-Induced Systemic Venous Hypertension in the Fontan Circulation.

    PubMed

    Navaratnam, Devaraj; Fitzsimmons, Samantha; Grocott, Michael; Rossiter, Harry B; Emmanuel, Yaso; Diller, Gerard-Paul; Gordon-Walker, Timothy; Jack, Sandy; Sheron, Nick; Pappachan, John; Pratap, Jayant Nick; Vettukattil, Joseph J; Veldtman, Gruschen

    2016-05-15

    Increasingly end-organ injury is being demonstrated late after institution of the Fontan circulation, particularly liver fibrosis and cirrhosis. The exact mechanisms for these late phenomena remain largely elusive. Hypothesizing that exercise induces precipitous systemic venous hypertension and insufficient cardiac output for the exercise demand, that is, a possible mechanism for end-organ injury, we sought to demonstrate the dynamic exercise responses in systemic venous perfusion (SVP) and concurrent end-organ perfusion. Ten stable Fontan patients and 9 control subjects underwent incremental cycle ergometry-based cardiopulmonary exercise testing. SVP was monitored in the right upper limb, and regional tissue oxygen saturation was monitored in the brain and kidney using near-infrared spectroscopy. SVP rose profoundly in concert with workload in the Fontan group, described by the regression equation 15.97 + 0.073 watts per mm Hg. In contrast, SVP did not change in healthy controls. Regional renal (p <0.01) and cerebral tissue saturations (p <0.001) were significantly lower and decrease more rapidly in Fontan patients. We conclude that in a stable group of adult patients with Fontan circulation, high-intensity exercise was associated with systemic venous hypertension and reduced systemic oxygen delivery. This physiological substrate has the potential to contribute to end-organ injury. PMID:27032711

  2. Resistance to exercise-induced weight loss: compensatory behavioral adaptations.

    PubMed

    Melanson, Edward L; Keadle, Sarah Kozey; Donnelly, Joseph E; Braun, Barry; King, Neil A

    2013-08-01

    In many interventions that are based on an exercise program intended to induce weight loss, the mean weight loss observed is modest and sometimes far less than what the individual expected. The individual responses are also widely variable, with some individuals losing a substantial amount of weight, others maintaining weight, and a few actually gaining weight. The media have focused on the subpopulation that loses little weight, contributing to a public perception that exercise has limited utility to cause weight loss. The purpose of the symposium was to present recent, novel data that help explain how compensatory behaviors contribute to a wide discrepancy in exercise-induced weight loss. The presentations provide evidence that some individuals adopt compensatory behaviors, that is, increased energy intake and/or reduced activity, that offset the exercise energy expenditure and limit weight loss. The challenge for both scientists and clinicians is to develop effective tools to identify which individuals are susceptible to such behaviors and to develop strategies to minimize their effect. PMID:23470300

  3. Resistance to exercise-induced weight loss: compensatory behavioral adaptations

    PubMed Central

    Melanson, Edward L.; Keadle, Sarah Kozey; Donnelly, Joseph E.; Braun, Barry; King, Neil A.

    2013-01-01

    In many interventions that are based on an exercise program intended to induce weight loss, the mean weight loss observed is modest and sometimes far less than the individual expected. The individual responses are also widely variable, with some individuals losing a substantial amount of weight, others maintaining weight, and a few actually gaining weight. The media have focused on the sub-population that loses little weight, contributing to a public perception that exercise has limited utility to cause weight loss. The purpose of the symposium was to present recent, novel data that help explain how compensatory behaviors contribute to a wide discrepancy in exercise-induced weight loss. The presentations provide evidence that some individuals adopt compensatory behaviors, i.e. increased energy intake and/or reduced activity, that offset the exercise energy expenditure and limit weight loss. The challenge for both scientists and clinicians is to develop effective tools to identify which individuals are susceptible to such behaviors, and to develop strategies to minimize their impact. PMID:23470300

  4. Acute versus chronic exercise-induced left-ventricular remodeling.

    PubMed

    Weiner, Rory B; Baggish, Aaron L

    2014-11-01

    Exercise-induced cardiac remodeling (EICR) is the process by which the heart adapts to the physiologic stress of exercise. Non-invasive cardiovascular imaging has led to advances in the understanding of EICR, with sport-specific changes in left-ventricular (LV) structure and function being described; however, the majority of data stem from cross-sectional and short-duration longitudinal studies. Due to the paucity of long-term longitudinal EICR studies, the time course of this process and any distinct differentiation between acute and chronic adaptations remain largely unexplored. In order to clarify the natural history of EICR, longer duration longitudinal study is required. Such work will determine whether exercise-induced changes in myocardial structure and function occur in discrete stages. Examination of prolonged exposures to exercise training will also be necessary to determine normative values across the age and training spectrums of athletic patients. This information will help to distinguish the boundary between physiology and pathology in athletic patients. PMID:25300444

  5. Effect of non-symmetric waveform on conduction block induced by high-frequency (kHz) biphasic stimulation in unmyelinated axon.

    PubMed

    Zhao, Shouguo; Yang, Guangning; Wang, Jicheng; Roppolo, James R; de Groat, William C; Tai, Changfeng

    2014-10-01

    The effect of a non-symmetric waveform on nerve conduction block induced by high-frequency biphasic stimulation is investigated using a lumped circuit model of the unmyelinated axon based on Hodgkin-Huxley equations. The simulation results reveal that the block threshold monotonically increases with the stimulation frequency for the symmetric stimulation waveform. However, a non-monotonic relationship between block threshold and stimulation frequency is observed when the stimulation waveform is non-symmetric. Constant activation of potassium channels by the high-frequency stimulation results in the increase of block threshold with increasing frequency. The non-symmetric waveform with a positive pulse 0.4-0.8 μs longer than the negative pulse blocks axonal conduction by hyperpolarizing the membrane and causes a decrease in block threshold as the frequency increases above 12-16 kHz. On the other hand, the non-symmetric waveform with a negative pulse 0.4-0.8 μs longer than the positive pulse blocks axonal conduction by depolarizing the membrane and causes a decrease in block threshold as the frequency increases above 40-53 kHz. This simulation study is important for understanding the potential mechanisms underlying the nerve block observed in animal studies, and may also help to design new animal experiments to further improve the nerve block method for clinical applications. PMID:24928360

  6. Exercise-induced ROS in heat shock proteins response.

    PubMed

    Dimauro, Ivan; Mercatelli, Neri; Caporossi, Daniela

    2016-09-01

    Cells have evolved multiple and sophisticated stress response mechanisms aiming to prevent macromolecular (including proteins, lipids, and nucleic acids) damage and to maintain or re-establish cellular homeostasis. Heat shock proteins (HSPs) are among the most highly conserved, ubiquitous, and abundant proteins in all organisms. Originally discovered more than 50 years ago through heat shock stress, they display multiple, remarkable roles inside and outside cells under a variety of stresses, including also oxidative stress and radiation, recognizing unfolded or misfolded proteins and facilitating their restructuring. Exercise consists in a combination of physiological stresses, such as metabolic disturbances, changes in circulating levels of hormones, increased temperature, induction of mild to severe inflammatory state, increased production of reactive oxygen and nitrogen species (ROS and RNS). As a consequence, exercise is one of the main stimuli associated with a robust increase in different HSPs in several tissues, which appears to be also fundamental in facilitating the cellular remodeling processes related to the training regime. Among all factors involved in the exercise-related modulation of HSPs level, the ROS production in the contracting muscle or in other tissues represents one of the most attracting, but still under discussion, mechanism. Following exhaustive or damaging muscle exercise, major oxidative damage to proteins and lipids is likely involved in HSP expression, together with mechanically induced damage to muscle proteins and the inflammatory response occurring several days into the recovery period. Instead, the transient and reversible oxidation of proteins by physiological concentrations of ROS seems to be involved in the activation of stress response following non-damaging muscle exercise. This review aims to provide a critical update on the role of HSPs response in exercise-induced adaptation or damage in humans, focusing on experimental

  7. The accumulations of HIF-1α and HIF-2α by JNK and ERK are involved in biphasic effects induced by different levels of arsenite in human bronchial epithelial cells

    SciTech Connect

    Xu, Yuan; Li, Yuan; Li, Huiqiao; Pang, Ying; Zhao, Yue; Jiang, Rongrong; Shen, Lu; Zhou, Jianwei; Wang, Xinru; Liu, Qizhan

    2013-01-15

    The biphasic effects of arsenite, in which low levels of arsenite induce cell proliferation and high levels of arsenite induce DNA damage and apoptosis, apparently contribute to arsenite-induced carcinogenesis. However, the mechanisms underlying this phenomenon are not well understood. In this study, we investigated the effects of different levels of arsenite on cell proliferation, DNA damage and apoptosis as well as on signal transduction pathways in human bronchial epithelial (HBE) cells. Our results show that a low level of arsenite activates extracellular signal-regulated kinases (ERK), which probably mediate arsenite-inhibited degradation of ubiquitinated hypoxia-inducible factor-2α (HIF-2α) in HBE cells. ERK inhibition blocks cell proliferation induced by a low level of arsenite, in part via HIF-2α. In contrast, a high level of arsenite activates c-Jun N-terminal kinases (JNK), which provoke a response to suppress ubiquitinated HIF-1α degradation. Down-regulation of HIF-1α by inhibiting JNK, however, increases the DNA damage but decreases the apoptosis induced by a high level of arsenite. Thus, data in the present study suggest that the accumulations of HIF-1α and HIF-2α by JNK and ERK are involved in different levels of arsenite-induced biphasic effects, with low levels of arsenite inducing cell proliferation and high levels of arsenite inducing DNA damage and apoptosis in HBE cells. -- Highlights: ► Biphasic effects induced by different concentrations of arsenite. ► Different regulation of ERK or JNK signal pathway by arsenite. ► Different regulation of HIF1α or HIF 2α by arsenite.

  8. Exercises

    MedlinePlus

    ... Obstructive Pulmonary Disease (COPD) COPD: Lifestyle Management Exercises Exercises Make an Appointment Refer a Patient Ask a ... riding a stationary bike. Medication to Help You Exercise People with COPD often use a metered-dose ...

  9. Thyroid Hormone and Estrogen Regulate Exercise-Induced Growth Hormone Release

    PubMed Central

    Ignacio, Daniele Leão; da S. Silvestre, Diego H.; Cavalcanti-de-Albuquerque, João Paulo Albuquerque; Louzada, Ruy Andrade

    2015-01-01

    Growth hormone (GH) regulates whole body metabolism, and physical exercise is the most potent stimulus to induce its secretion in humans. The mechanisms underlying GH secretion after exercise remain to be defined. The aim of this study was to elucidate the role of estrogen and pituitary type 1 deiodinase (D1) activation on exercise-induced GH secretion. Ten days after bilateral ovariectomy, animals were submitted to 20 min of treadmill exercise at 75% of maximum aerobic capacity and tissues were harvested immediately or 30 min after exercise. Non-exercised animals were used as controls. A significant increase in D1 activity occurred immediately after exercise (~60%) in sham-operated animals and GH was higher (~6-fold) 30 min after exercise. Estrogen deficient rats exhibited basal levels of GH and D1 activity comparable to those found in control rats. However, after exercise both D1 activity and serum GH levels were blunted compared to sedentary rats. To understand the potential cause-effect of D1 activation in exercise-induced GH release, we pharmacologically blocked D1 activity by propylthiouracil (PTU) injection into intact rats and submitted them to the acute exercise session. D1 inhibition blocked exercise-induced GH secretion, although basal levels were unaltered. In conclusion, estrogen deficiency impairs the induction of thyroid hormone activating enzyme D1 in the pituitary, and GH release by acute exercise. Also, acute D1 activation is essential for exercise-induced GH response. PMID:25874614

  10. Thyroid hormone and estrogen regulate exercise-induced growth hormone release.

    PubMed

    Ignacio, Daniele Leão; da S Silvestre, Diego H; Cavalcanti-de-Albuquerque, João Paulo Albuquerque; Louzada, Ruy Andrade; Carvalho, Denise P; Werneck-de-Castro, João Pedro

    2015-01-01

    Growth hormone (GH) regulates whole body metabolism, and physical exercise is the most potent stimulus to induce its secretion in humans. The mechanisms underlying GH secretion after exercise remain to be defined. The aim of this study was to elucidate the role of estrogen and pituitary type 1 deiodinase (D1) activation on exercise-induced GH secretion. Ten days after bilateral ovariectomy, animals were submitted to 20 min of treadmill exercise at 75% of maximum aerobic capacity and tissues were harvested immediately or 30 min after exercise. Non-exercised animals were used as controls. A significant increase in D1 activity occurred immediately after exercise (~60%) in sham-operated animals and GH was higher (~6-fold) 30 min after exercise. Estrogen deficient rats exhibited basal levels of GH and D1 activity comparable to those found in control rats. However, after exercise both D1 activity and serum GH levels were blunted compared to sedentary rats. To understand the potential cause-effect of D1 activation in exercise-induced GH release, we pharmacologically blocked D1 activity by propylthiouracil (PTU) injection into intact rats and submitted them to the acute exercise session. D1 inhibition blocked exercise-induced GH secretion, although basal levels were unaltered. In conclusion, estrogen deficiency impairs the induction of thyroid hormone activating enzyme D1 in the pituitary, and GH release by acute exercise. Also, acute D1 activation is essential for exercise-induced GH response. PMID:25874614

  11. Exploring the Relationship between Exercise-Induced Arousal and Cognition Using Fractionated Response Time

    ERIC Educational Resources Information Center

    Chang, Yu-Kai; Etnier, Jennifer L.; Barella, Lisa A.

    2009-01-01

    Although a generally positive effect of acute exercise on cognitive performance has been demonstrated, the specific nature of the relationship between exercise-induced arousal and cognitive performance remains unclear. This study was designed to identify the relationship between exercise-induced arousal and cognitive performance for the central…

  12. Lycium barbarum polysaccharides reduce exercise-induced oxidative stress.

    PubMed

    Shan, Xiaozhong; Zhou, Junlai; Ma, Tao; Chai, Qiongxia

    2011-01-01

    The purpose of the present study was to investigate the effects of Lycium barbarum polysaccharides (LBP) on exercise-induced oxidative stress in rats. Rats were divided into four groups, i.e., one control group and three LBP treated groups. The animals received an oral administration of physiological saline or LBP (100, 200 and 400 mg/kg body weight) for 28 days. On the day of the exercise test, rats were required to run to exhaustion on the treadmill. Body weight, endurance time, malondialdehyde (MDA), super oxide dismutase (SOD) and glutathione peroxidase (GPX) level of rats were measured. The results showed that the body weight of rats in LBP treated groups were not significantly different from that in the normal control group before and after the experiment (P > 0.05). After exhaustive exercise, the mean endurance time of treadmill running to exhaustion of rats in LBP treated groups were significantly prolonged compared with that in the normal control group. MDA levels of rats in LBP treated groups were significantly decreased compared with that in the normal control group (P < 0.05). SOD and GPX levels of rats in LBP treated groups were significantly increased compared with that in the normal control group (P < 0.05). Together, these results indicate that LBP was effective in preventing oxidative stress after exhaustive exercise. PMID:21541044

  13. Metabolic consequences of exercise-induced muscle damage.

    PubMed

    Tee, Jason C; Bosch, Andrew N; Lambert, Mike I

    2007-01-01

    Exercise-induced muscle damage (EIMD) is commonly experienced following either a bout of unaccustomed physical activity or following physical activity of greater than normal duration or intensity. The mechanistic factor responsible for the initiation of EIMD is not known; however, it is hypothesised to be either mechanical or metabolic in nature. The mechanical stress hypothesis states that EIMD is the result of physical stress upon the muscle fibre. In contrast, the metabolic stress model predicts that EIMD is the result of metabolic deficiencies, possibly through the decreased action of Ca(2+)-adenosine triphosphatase. Irrespective of the cause of the damage, EIMD has a number of profound metabolic effects. The most notable metabolic effects of EIMD are decreased insulin sensitivity, prolonged glycogen depletion and an increase in metabolic rate both at rest and during exercise. Based on current knowledge regarding the effects that various types of damaging exercise have on muscle metabolism, a new model for the initiation of EIMD is proposed. This model states that damage initiation may be either metabolic or mechanical, or a combination of both, depending on the mode, intensity and duration of exercise and the training status of the individual. PMID:17887809

  14. Keeping children with exercise-induced asthma active.

    PubMed

    Milgrom, H; Taussig, L M

    1999-09-01

    Exercise-induced bronchospasm, exercise-induced bronchoconstriction, and exercise-induced asthma (EIA) are all terms used to describe the phenomenon of transient airflow obstruction associated with physical exertion. It is a prominent finding in children and young adults because of their greater participation in vigorous activities. The symptoms shortness of breath, cough, chest tightness, and wheezing normally follow the brief period of bronchodilation present early in the course of exercise. Bronchospasm typically arises within 10 to 15 minutes of beginning exercise, peaks 8 to 15 minutes after the exertion is concluded, and resolves about 60 minutes later, but it also may appear during sustained exertion. EIA occurs in up to 90% of asthmatics and 40% of patients with allergic rhinitis; among athletes and in the general population its prevalence is between 6% and 13%. EIA frequently goes undiagnosed. Approximately 9% of individuals with EIA have no history of asthma or allergy. Fifty percent of children with asthma who gave a negative history for EIA had a positive response to exercise challenge.6 Among high school athletes, 12% of subjects not considered to be at risk by history or baseline spirometry tested positive. Before the 1984 Olympic games, of 597 members of the US team, 67 (11%) were found to have EIA. Remarkably, only 26 had been previously identified, emphasizing the importance of screening for EIA even in well-conditioned individuals who appear to be in excellent health. The severity of bronchospasm in EIA is related to the level of ventilation, to heat and water loss from the respiratory tree, and also to the rate of airway rewarming and rehydration after the challenge. Postexercise decrease in the peak expiratory flow rate of normal children may be as much as 15%; therefore, only a decrease in excess of 15% should be viewed as diagnostic. EIA is usually provoked by a workload sufficient to produce 80% of maximum oxygen consumption; however, in

  15. Diaphragmatic breathing reduces exercise-induced oxidative stress.

    PubMed

    Martarelli, Daniele; Cocchioni, Mario; Scuri, Stefania; Pompei, Pierluigi

    2011-01-01

    Diaphragmatic breathing is relaxing and therapeutic, reduces stress, and is a fundamental procedure of Pranayama Yoga, Zen, transcendental meditation and other meditation practices. Analysis of oxidative stress levels in people who meditate indicated that meditation correlates with lower oxidative stress levels, lower cortisol levels and higher melatonin levels. It is known that cortisol inhibits enzymes responsible for the antioxidant activity of cells and that melatonin is a strong antioxidant; therefore, in this study, we investigated the effects of diaphragmatic breathing on exercise-induced oxidative stress and the putative role of cortisol and melatonin hormones in this stress pathway. We monitored 16 athletes during an exhaustive training session. After the exercise, athletes were divided in two equivalent groups of eight subjects. Subjects of the studied group spent 1 h relaxing performing diaphragmatic breathing and concentrating on their breath in a quiet place. The other eight subjects, representing the control group, spent the same time sitting in an equivalent quite place. Results demonstrate that relaxation induced by diaphragmatic breathing increases the antioxidant defense status in athletes after exhaustive exercise. These effects correlate with the concomitant decrease in cortisol and the increase in melatonin. The consequence is a lower level of oxidative stress, which suggests that an appropriate diaphragmatic breathing could protect athletes from long-term adverse effects of free radicals. PMID:19875429

  16. The protective effect of ketotifen in exercise-induced bronchospasm.

    PubMed

    Moreno, M V; Fernández, M; de la Cuesta, C G; Oehling, A

    1988-01-01

    The present study evaluates the protective action of ketotifen on exercise-induced bronchospasm in patients diagnosed with bronchial asthma of different aetiologies. The patients were classified in 2 groups. The first group with seasonal asthma was made up of patients with pollen hypersensitivity, while the second group with perennial asthma was made up of patients with bacterial aetiology or sensitivity to the Dermatophagoides mite. Spirometry and airway resistance measurements (in basal conditions, 5 to 10 minutes after a resistance test which consisted of 6 minutes' free running on a treadmill) was performed on each patient. Those patients in which significant spirometry or Raw alterations were detected received a 15-day treatment of ketotifen (a dose of 1 mg every 12 hours); after this time, the tests mentioned before were repeated. We found that in the seasonal asthma group, ketotifen was effective in protecting against exercise. However, we did not observe the same effect in the perennial asthma group. In the light of these results, we propose the possible existence of different mechanisms in triggering off exercise-induced bronchospasm, according to their aetiologies. PMID:3394595

  17. Transitory endolymph leakage induced hearing loss and tinnitus: depolarization, biphasic shortening and loss of electromotility of outer hair cells

    NASA Technical Reports Server (NTRS)

    Zenner, H. P.; Reuter, G.; Zimmermann, U.; Gitter, A. H.; Fermin, C.; LePage, E. L.

    1994-01-01

    There are types of deafness and tinnitus in which ruptures or massive changes in the ionic permeability of the membranes lining the endolymphatic space [e.g., of the reticular lamina (RL)] are believed to allow potassium-rich endolymph to deluge the low [K+] perilymphatic fluid (e.g., in the small spaces of Nuel). This would result in a K+ intoxication of sensory and neural structures. Acute attacks of Meniere's disease have been suggested to be an important example for this event. The present study investigated the effects of transiently elevated [K+] due to the addition of artificial endolymph to the basolateral cell surface of outer hair cells (OHC) in replicating endolymph-induced K+ intoxication of the perilymph in the small spaces of Nuel. The influence of K+ intoxication of the basolateral OHC cell surface on the transduction was then examined. Intoxication resulted in an inhibition of the physiological repolarizing K+ efflux from hair cells. This induced unwanted depolarizations of the hair cells, interfering with mechanoelectrical transduction. A pathological longitudinal OHC shortening was also found, with subsequent compression of the organ of Corti possibly influencing the micromechanics of the mechanically active OHC. Both micromechanical and electrophysiological alterations are proposed to contribute to endolymph leakage induced attacks of deafness and possibly also to tinnitus. Moreover, repeated or long-lasting K+ intoxications of OHC resulted in a chronic and complete loss of OHC motility. This is suggested to be a pathophysiological basis in some patients with chronic hearing loss resulting from Meniere's syndrome.

  18. A 45-Year-Old Man With Recurrent Dyspnea and Hemoptysis during Exercise: Exercise-Induced Pulmonary Hemorrhage/Edema

    PubMed Central

    Kim, Dae Sung; Lee, Minhyeok; Kwon, Oh Jung; Jeong, Inbeom; Son, Ji Woong; Na, Moon Jun

    2015-01-01

    A 45-year-old man presented with dyspnea and hemoptysis during exercise. A chest computed tomography (CT) revealed multifocal diffuse patchy ground glass opacity and interlobular septal thickening in both the lungs. Permeability pulmonary edema or pulmonary hemorrhage was suspected. Serologic studies for autoimmune disorders and vasculitis were negative. There was no laboratory evidence of coagulopathy, other hematopoietic disease or infectious disease. Considering correlation with exercise, we diagnosed exercise-induced pulmonary hemorrhage (EIPH) or exercise-induced pulmonary edema (EIPE). The patient was managed with antifibrinolytics, antibiotics, and antitussive agent. After a week, follow-up chest CT revealed completely resolved pulmonary hemorrhage. About 2 months after the first event, he visited again with dyspnea and hemoptysis during running. In the present study, we report a case of recurrent pulmonary hemorrhage after exercise. PMID:26508928

  19. Biphasic Response to Luteolin in MG-63 Osteoblast-Like Cells under High Glucose-Induced Oxidative Stress

    PubMed Central

    Abbasi, Naser; Khosravi, Afra; Aidy, Ali; Shafiei, Massoumeh

    2016-01-01

    Background: Clinical evidence indicates the diabetes-induced impairment of osteogenesis caused by a decrease in osteoblast activity. Flavonoids can increase the differentiation and mineralization of osteoblasts in a high-glucose state. However, some flavonoids such as luteolin may have the potential to induce cytotoxicity in osteoblast-like cells. This study was performed to investigate whether a cytoprotective concentration range of luteolin could be separated from a cytotoxic concentration range in human MG-63 osteoblast-like cells in high-glucose condition. Methods: Cells were cultured in a normal- or high-glucose medium. Cell viability was determined with the MTT assay. The formation of intracellular reactive oxygen species (ROS) was measured using probe 2’,7’ -dichlorofluorescein diacetate, and osteogenic differentiation was evaluated with an alkaline phosphatase bioassay. Results: ROS generation, reduction in alkaline phosphatase activity, and cell death induced by high glucose were inhibited by lower concentrations of luteolin (EC50, 1.29±0.23 µM). Oxidative stress mediated by high glucose was also overcome by N-acetyl-L-cysteine. At high concentrations, luteolin caused osteoblast cell death in normal- and high-glucose states (IC50, 34±2.33 and 27±2.42 µM, respectively), as represented by increased ROS and decreased alkaline phosphatase activity. Conclusion: Our results indicated that the cytoprotective action of luteolin in glucotoxic condition was manifested in much lower concentrations, by a factor of approximately 26 and 20, than was its cytotoxic activity, which occurred under normal or glucotoxic condition, respectively. PMID:26989282

  20. [Exercise-induced airway obstruction in asthmatic children and adolescents].

    PubMed

    Zapletal, A; Zbojan, J; Pohanka, V

    1992-03-01

    In 115 asymptomatic asthmatic children and adolescents (age 6-18 years) there was studied the magnitude of airway obstruction, induced by various physical efforts and assessed from the recording of maximum expiratory flow-volume curves and in some patients by "specific" airway conductance measurement in a body plethysmograph. The effects of 5 minutes free running outdoors, 5 minutes of exercise on a bicycle ergometer (2 watts/kg of body weight), routine swimming training in swimming pool and of forced expiration maneuver on the magnitude of airway obstruction were assessed. The most frequent and largest degree of airway obstruction was observed after 5 min. free running outdoors (heart rate after running 160-200/min). The obstruction was revealed in 80-100% asthmatics in various groups. The chosen lung function parameters showed exercise-induced airway obstruction in the same patients in various proportions as well as the magnitude of the obstruction. Following free running outdoors the values of maximum expiratory flow at 25% of vital capacity and "specific" airway conductance were most reduced. Spontaneous retreat of obstruction was observed in the course of 2 hours. The physical exercise on a bicycle ergometer was a small stimulus in inducing of airway obstruction. The swimming in a pool did not provoke any obstruction. In 10% of our asthmatics airway obstruction was observed following forced expiration maneuver. Airway obstruction induced by 5 minutes free running outdoors and assessed best by flow-volume curves appeared as a suitable test in the assessment of airway hyperresponsiveness. PMID:1591810

  1. Biphasic response of checkpoint control proteins in hyperoxia: Exposure to lower levels of oxygen induces genome maintenance genes in experimental baboon BPD

    PubMed Central

    Das, Kumuda C.; Wasnick, John D.

    2014-01-01

    Breathing high concentrations of oxygen (hyperoxia) causes lung injury and is associated with lung diseases such as bronchopulmonary dysplasia (BPD), respiratory distress syndrome (RDS) and persistent pulmonary hypertension of the newborns (PPHN). Hyperoxia (95–100%O2) causes DNA damage and growth arrest of lung cells and consequently cells die by apoptosis or necrosis. Although supplemental oxygen therapy is clinically important, the level and duration of hyperoxic exposure that would allow lung cells to reenter the cell cycle remains unclear. We hypothesized that cells exposed lower concentrations of hyperoxia will retain the capacity to enter cell cycle when recovered in room air. We employed varying concentrations of oxygen (21–95%) to determine the response of lung cells to hyperoxia. Our results indicate that cells were growth arrested and failed to reenter the cell cycle when exposed to greater than 60% oxygen. Cell cycle checkpoint proteins were increased in a biphasic manner, increasing until 70% oxygen, but declined in greater than 90% oxygen. Microarray analysis shows that there is significant decrease in the abundance of Cdks 6–8 and retinoblastoma protein (Rb), p107 and p130 in exposure to 90% oxygen for 48 hours. We further tested the effect of clinically relevant as needed oxygen [(pro-re-nada (prn)] in premature infant (125d and 140d) baboon model of bronchopulmonary dysplasia (BPD). The microarray results show that 6 or 14d PRN oxygen exposed animals had induced expression of chromosomal maintenance genes (MCMs), genes related to anti-inflammation, proliferation and differentiation. PMID:24939362

  2. Cannabinoid receptor 1 induces a biphasic ERK activation via multiprotein signaling complex formation of proximal kinases PKCε, Src, and Fyn in primary neurons.

    PubMed

    Asimaki, Olga; Mangoura, Dimitra

    2011-02-01

    Cannabinoid receptors 1 (CB1Rs) play important roles in the regulation of dendritic branching, synapse density, and synaptic transmission through multiple G-protein-coupled signaling systems, including the activation of the extracellular signal-regulated kinases ERK1/2. The proximal signaling interactions leading to ERK1/2 activation by CB1R in CNS remain, however, unclear. Here, we present evidence that the CB1R agonist methanandamide induced a biphasic and sustained activation of ERK1/2 in primary neurons derived from E7 telencephalon. We show that E7 neurons natively express high levels of CB1R message and protein, the majority of which associates with PKCɛ at basal conditions. We now demonstrate that the first peak of ERK activation by CB1R was mediated by the sequential activation of G(q), PLC, and PKCɛ, selectively, and that the CB1R-activated PKCɛ acutely formed transient signaling modules containing activated Src and Fyn. A second pool of CB1Rs, coupled to PTX-sensitive activation of G(i/o), utilized as effectors additional Src and Fyn molecules to generate a second, additional wave of ERK activation at 15 min. Concurrently to these intermolecular signaling interactions, cytoskeleton-associated proteins MARCKS and p120catenin were drastically modified by phosphorylation of PKC and Src, respectively. These receptor-proximal signaling events correlated well with induction of neuritic outgrowth in the long term. Our data provide evidence for multiprotein signaling complex formation in the coupling of CB1R to activation of ERK in CNS neurons, and may elucidate several of the less understood acute effects of cannabinoid drugs. PMID:21074588

  3. [Exercise-induced shear stress: Physiological basis and clinical impact].

    PubMed

    Rodríguez-Núñez, Iván; Romero, Fernando; Saavedra, María Javiera

    2016-01-01

    The physiological regulation of vascular function is essential for cardiovascular health and depends on adequate control of molecular mechanisms triggered by endothelial cells in response to mechanical and chemical stimuli induced by blood flow. Endothelial dysfunction is one of the major risk factors for cardiovascular disease, where an imbalance between synthesis of vasodilator and vasoconstrictor molecules is one of its main mechanisms. In this context, the shear stress is one of the most important mechanical stimuli to improve vascular function, due to endothelial mechanotransduction, triggered by stimulation of various endothelial mechanosensors, induce signaling pathways culminating in increased bioavailability of vasodilators molecules such as nitric oxide, that finally trigger the angiogenic mechanisms. These mechanisms allow providing the physiological basis for the effects of exercise on vascular health. In this review it is discussed the molecular mechanisms involved in the vascular response induced by shear stress and its impact in reversing vascular injury associated with the most prevalent cardiovascular disease in our population. PMID:27118039

  4. Effect of simulated weightlessness on exercise-induced anaerobic threshold

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.; Karst, G. M.; Kirby, C. R.; Goldwater, D. J.

    1986-01-01

    The effect of simulated weightlessness, induced by ten days of continuous bedrest (BR) in the -6 deg head-down position, on the exercise-induced anaerobic threshold (AT) was determined by comparing specific ventilatory and gas-exchange measurements during an incremental ergometer test performed before and after BR. The primary index for determining the exercise-induced AT values of each subject was visual identification of the workrate or oxygen uptake (VO2) at which the ratio of the expired minute ventilation volume (VE) to VO2 exhibited a systematic increase without a concomitant increase in the VE/VCO2 value. Following BR, the mean VO2max of the subjects decreased by 7.0 percent, and the AT decreased from a mean of 1.26 L/min VO2 before BR to 0.95 L/min VO2 after BR. The decrease in AT was manifested by a decrease in both absolute and relative workrates. The change in AT correlated significantly with the change in plasma volume but not with the change in VO2max. The results suggest that the reduction in AT cannot be completely explained by the reduction in VO2, and that the AT decrease is associated with the reduction in intravascular fluid volume.

  5. Exercise Training suppresses vascular fibrosis in aging obesity induced rats

    PubMed Central

    Kim, Shin Young; Lee, Jin

    2014-01-01

    [Purpose] The aim of this study was to investigate the effects of exercise training (ET) on vascular fibrosis in aging model rats with diet-induced obesity. [Methods] Twenty-four male Sprague-Dawley rats were divided into 3 groups: Aging control (A-C), A-C with high fat diet (AHF), AHF with ET (AHF + ET). Aging was induced by D-galactose (D-gal) and obesity was induced by HFD (60% fat) for 9 weeks. The experimental rats performed swimming (60 min/day, 5 days/week) for 8 weeks. All rat aorta samples were harvested for RT-PCR and morphologic analyses. [Results] The exercise training significantly decreased levels of AT-1, TGF-ß and Coll-1 gene expression compared to AHF group. The AHF + ET group showed a reduced collagen accumulation in the aorta media compared to AHF group. [Conclusion] These results suggest that ET could protect the aging obesity aorta against down-regulation of fibrotic factors (AT-1, TGF-ß and Coll-1 gene) and fibrosis by inhibition of collagen accumulation in the aorta media. PMID:25566453

  6. Exercise-induced effects on a gym atmosphere.

    PubMed

    Žitnik, M; Bučar, K; Hiti, B; Barba, Ž; Rupnik, Z; Založnik, A; Žitnik, E; Rodrìguez, L; Mihevc, I; Žibert, J

    2016-06-01

    We report results of analysis of a month-long measurement of indoor air and environment quality parameters in one gym during sporting activities such as football, basketball, volleyball, badminton, boxing, and fitness. We have determined an average single person's contribution to the increase of temperature, humidity, and dust concentration in the gym air volume of 12500 m(3) : during 90-min exercise performed at an average heart rate of 143 ± 10 bpm, a single person evaporated 0.94 kg of water into the air by sweating, contributed 0.03 K to the air temperature rise and added 1.5 μg/m(3) and 5 ng/m(3) to the indoor concentration of inhalable particles (PM10 ) and Ca concentration, respectively. As the breathing at the observed exercise intensity was about three times faster with respect to the resting condition and as the exercise-induced PM10 concentration was about two times larger than outdoors, a sportsman in the gym would receive about a sixfold higher dose of PM10 inside than he/she would have received at rest outside. PMID:26095910

  7. Oxidation of RyR2 Has a Biphasic Effect on the Threshold for Store Overload-Induced Calcium Release.

    PubMed

    Waddell, Helen M M; Zhang, Joe Z; Hoeksema, Katie J; McLachlan, Julia J; McLay, Janet C; Jones, Peter P

    2016-06-01

    At the single-channel level, oxidation of the cardiac ryanodine receptor (RyR2) is known to activate and inhibit the channel depending on the level of oxidation. However, the mechanisms through which these changes alter the activity of RyR2 in a cellular setting are poorly understood. In this study, we determined the effect of oxidation on a common form of RyR2 regulation; store overload-induced Ca(2+) release (SOICR). We found that oxidation resulted in concentration and time-dependent changes in the activation threshold for SOICR. Low concentrations of the oxidant H2O2 resulted in a decrease in the threshold for SOICR, which led to an increase in SOICR events. However, higher concentrations of H2O2, or prolonged exposure, reversed these changes and led to an increase in the threshold for SOICR. This increase in the threshold for SOICR in most cells was to such an extent that it led to the complete inhibition of SOICR. Acute exposure to high concentrations of H2O2 led to an initial decrease and then increase in the threshold for SOICR. In the majority of cells the increased threshold could not be reversed by the application of the reducing agent dithiothreitol. Therefore, our data suggest that low levels of RyR2 oxidation increase the channel activity by decreasing the threshold for SOICR, whereas high levels of RyR2 oxidation irreversibly increase the threshold for SOICR leading to an inhibition of RyR2. Combined, this indicates that oxidation regulates RyR2 by the same mechanism as phosphorylation, methylxanthines, and mutations, via changes in the threshold for SOICR. PMID:27276257

  8. Effects of inhaled thiazinamium chloride on histamine-induced and exercise-induced bronchoconstriction.

    PubMed

    Gong, H; Brik, A; Tashkin, D P; Dauphinee, B

    1989-03-01

    The protective efficacy of aerosolized thiazinamium chloride (TC) against histamine-induced and exercise-induced bronchoconstriction was evaluated in 15 subjects with stable, mild asthma. Following reproducible bronchoprovocation with these stimuli, each subject underwent randomized, double-blind, crossover pretreatment with single doses of nebulized TC (300, 600, and 900 micrograms), placebo, and an active control drug (metaproterenol or cromolyn), followed by histamine or exercise challenge (two separate protocols). The results indicated that all doses of TC significantly blocked histamine-induced bronchoconstriction as compared with placebo. Overall, aerosolized TC was ineffective in blocking exercise-induced bronchoconstriction, although 900 micrograms TC tended to be more effective than placebo. Thiazinamium (900 micrograms) produced a modest bronchodilator effect. No clinically significant adverse effects related to TC occurred. We conclude that aerosolized TC is effective in attenuating histamine-induced but not exercise-induced bronchoconstriction in the doses studied. Further studies are warranted to evaluate the role of TC in asthma therapy. PMID:2564267

  9. Exercise-induced albuminuria is related to metabolic syndrome.

    PubMed

    Greenberg, Sharon; Shenhar-Tsarfaty, Shani; Rogowski, Ori; Shapira, Itzhak; Zeltser, David; Weinstein, Talia; Lahav, Dror; Vered, Jaffa; Tovia-Brodie, Oholi; Arbel, Yaron; Berliner, Shlomo; Milwidsky, Assi

    2016-06-01

    Microalbuminuria (MA) is a known marker for endothelial dysfunction and future cardiovascular events. Exercise-induced albuminuria (EiA) may precede the appearance of MA. Associations between EiA and metabolic syndrome (MS) have not been assessed so far. Our aim was to investigate this association in a large sample of apparently healthy individuals with no baseline albuminuria. This was a cross-sectional study of 2,027 adults with no overt cardiovascular diseases who took part in a health survey program and had no baseline MA. Diagnosis of MS was based on harmonized criteria. All patients underwent an exercise test (Bruce protocol), and urinary albumin was measured before and after the examination. Urinary albumin-to-creatinine ratio (ACR) values before and after exercise were 0.40 (0.21-0.89) and 1.06 (0.43-2.69) mg/g for median (interquartile range) respectively. A total of 394 (20%) subjects had EiA; ACR rose from normal rest values (0.79 mg/g) to 52.28 mg/g after exercise (P < 0.001); this effect was not shown for the rest of the study population. EiA was related to higher prevalence of MS (13.8% vs. 27.1%, P < 0.001), higher metabolic equivalents (P < 0.001), higher baseline blood pressure (P < 0.001), and higher levels of fasting plasma glucose, triglycerides, and body mass index (P < 0.001). Multivariate binary logistic regression model showed that subjects with MS were 98% more likely to have EiA (95% confidence interval: 1.13-3.46, P = 0.016). In conclusion, EiA in the absence of baseline MA is independently related to MS. PMID:27076648

  10. Asymmetry In Biphase Data Signals

    NASA Technical Reports Server (NTRS)

    Nguyen, Tien M.

    1992-01-01

    Report presents analysis of some effects of asymmetry in Manchester (biphase) binary data signal transmitted by phase modulation of sinusoidal carrier signal. Report extends analysis described in article, "Effects of Asymmetry of NRZ Data Signals on Performance" (NPO-18261), to include case where data biphase-modulated directly on residual carrier.

  11. The Effects of Creatine Supplementation on Exercise-Induced Muscle Damage.

    ERIC Educational Resources Information Center

    Rawson, Eric S.; Gunn, Bridget; Clarkson, Priscilla M.

    2001-01-01

    Investigated the effects of oral creatine (Cr) supplementation on markers of exercise-induced muscle damage following high-force eccentric exercise in men randomly administered Cr or placebo. Results indicated that 5 days of Cr supplementation did not reduce indirect makers of muscle damage or enhance recovery from high-force eccentric exercise.…

  12. Food-dependent exercise-induced anaphylaxis: is wheat unique?

    PubMed

    Wong, Gabriel K; Krishna, Mamidipudi T

    2013-12-01

    This review draws comparisons between wheat-dependent exercise-induced anaphylaxis (WDEIA) and other food-dependent exercise-induced anaphylaxis (FDEIAs) and discusses the importance of co-factors in its pathophysiology. FDEIA remains an enigmatic condition since it was first described 30 years ago. The sporadic and unpredictable nature of its reactions has puzzled clinicians and scientists for decades, but recent studies on WDEIA have enlightened us about the pathophysiology of this condition. The identification of defined allergic epitopes such as Tri a 19, α-gliadin, β-gliadin and γ-gliadin in WDEIA enables it to become the perfect model for studying FDEIA, but WDEIA is by no means a unique condition. On a larger scale, FDEIA represents a crucial link between IgE-mediated and anaphylactoid reactions and provides supportive evidence for the concept of 'summation anaphylaxis' and the need to overcome the 'allergen threshold'. Future work should focus on identifying more of the FDEIA epitopes and understanding their distinct molecular properties. The development of a biomarker in order to identify patients susceptible to co-factor influences would be invaluable. PMID:24127054

  13. Exercise-induced hormesis and skeletal muscle health.

    PubMed

    Ji, Li Li; Kang, Chounghun; Zhang, Yong

    2016-09-01

    Hormesis refers to the phenomenon that an exposure or repeated exposures of a toxin can elicit adaptive changes within the organism to resist to higher doses of toxin with reduced harm. Skeletal muscle shows considerable plasticity and adaptions in response to a single bout of acute exercise or chronic training, especially in antioxidant defense capacity and metabolic functions mainly due to remodeling of mitochondria. It has thus been hypothesized that contraction-induced production of reactive oxygen species (ROS) may stimulate the hormesis-like adaptations. Furthermore, there has been considerable evidence that select ROS such as hydrogen peroxide and nitric oxide, or even oxidatively degraded macromolecules, may serve as signaling molecules to stimulate such hermetic adaptations due to the activation of redox-sensitive signaling pathways. Recent research has highlighted the important role of nuclear factor (NF) κB, mitogen-activated protein kinase (MAPK), and peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), along with other newly discovered signaling pathways, in some of the most vital biological functions such as mitochondrial biogenesis, antioxidant defense, inflammation, protein turnover, apoptosis, and autophagy. The inability of the cell to maintain proper redox signaling underlies mechanisms of biological aging, during which inflammatory and catabolic pathways prevail. Research evidence and mechanisms connecting exercise-induced hormesis and redox signaling are reviewed. PMID:26916558

  14. Increased atrial arrhythmia susceptibility induced by intense endurance exercise in mice requires TNFα

    PubMed Central

    Aschar-Sobbi, Roozbeh; Izaddoustdar, Farzad; Korogyi, Adam S.; Wang, Qiongling; Farman, Gerrie P.; Yang, FengHua; Yang, Wallace; Dorian, David; Simpson, Jeremy A.; Tuomi, Jari M.; Jones, Douglas L.; Nanthakumar, Kumaraswamy; Cox, Brian; Wehrens, Xander H.T.; Dorian, Paul; Backx, Peter H.

    2015-01-01

    Atrial fibrillation (AF) is the most common supraventricular arrhythmia that, for unknown reasons, is linked to intense endurance exercise. Our studies reveal that 6 weeks of swimming or treadmill exercise improves heart pump function and reduces heart-rates. Exercise also increases vulnerability to AF in association with inflammation, fibrosis, increased vagal tone, slowed conduction velocity, prolonged cardiomyocyte action potentials and RyR2 phosphorylation (CamKII-dependent S2814) in the atria, without corresponding alterations in the ventricles. Microarray results suggest the involvement of the inflammatory cytokine, TNFα, in exercised-induced atrial remodelling. Accordingly, exercise induces TNFα-dependent activation of both NFκB and p38MAPK, while TNFα inhibition (with etanercept), TNFα gene ablation, or p38 inhibition, prevents atrial structural remodelling and AF vulnerability in response to exercise, without affecting the beneficial physiological changes. Our results identify TNFα as a key factor in the pathology of intense exercise-induced AF. PMID:25598495

  15. Increased atrial arrhythmia susceptibility induced by intense endurance exercise in mice requires TNFα.

    PubMed

    Aschar-Sobbi, Roozbeh; Izaddoustdar, Farzad; Korogyi, Adam S; Wang, Qiongling; Farman, Gerrie P; Yang, FengHua; Yang, Wallace; Dorian, David; Simpson, Jeremy A; Tuomi, Jari M; Jones, Douglas L; Nanthakumar, Kumaraswamy; Cox, Brian; Wehrens, Xander H T; Dorian, Paul; Backx, Peter H

    2015-01-01

    Atrial fibrillation (AF) is the most common supraventricular arrhythmia that, for unknown reasons, is linked to intense endurance exercise. Our studies reveal that 6 weeks of swimming or treadmill exercise improves heart pump function and reduces heart-rates. Exercise also increases vulnerability to AF in association with inflammation, fibrosis, increased vagal tone, slowed conduction velocity, prolonged cardiomyocyte action potentials and RyR2 phosphorylation (CamKII-dependent S2814) in the atria, without corresponding alterations in the ventricles. Microarray results suggest the involvement of the inflammatory cytokine, TNFα, in exercised-induced atrial remodelling. Accordingly, exercise induces TNFα-dependent activation of both NFκB and p38MAPK, while TNFα inhibition (with etanercept), TNFα gene ablation, or p38 inhibition, prevents atrial structural remodelling and AF vulnerability in response to exercise, without affecting the beneficial physiological changes. Our results identify TNFα as a key factor in the pathology of intense exercise-induced AF. PMID:25598495

  16. Blood Volume Changes Induced By Low-Intensity Intradialytic Exercise in Long-Term Hemodialysis Patients.

    PubMed

    Ookawara, Susumu; Miyazawa, Haruhisa; Ito, Kiyonori; Ueda, Yuichiro; Kaku, Yoshio; Hirai, Keiji; Hoshino, Taro; Mori, Honami; Yoshida, Izumi; Morishita, Yoshiyuki; Tabei, Kaoru

    2016-01-01

    Intradialytic exercise-induced blood volume (BV) reduction may cause intradialytic hypotension in hemodialysis (HD) patients. However, BV recovery time after intradialytic exercise remains unknown. Hemodialysis patients were recruited, and their relative BV change (%ΔBV) were measured with intradialytic exercise (n = 12). After confirming the linearity of %ΔBV for 30 min, patients exercised using a stationary cycle in the supine position. The target exercise intensity was a 10% increase in heart rate (HR), corresponding to relatively low-intensity exercise. Baseline %ΔBV (assumed baseline) were calculated for the 30 min before exercise using linear regression analysis. The mean intradialytic exercise start and end times after HD initiation were 93.0 ± 8.4 and 116.4 ± 8.3 min, respectively, a mean exercise duration of 23.5 ± 2.6 min. Percentage change in blood volume declined rapidly upon exercise initiation and gradually increased above the assumed baseline throughout HD. At the end of HD, %ΔBV in the exercise group was significantly higher than the assumed baseline (measured - assumed baseline %ΔBV: 2.17 ± 0.62%; p = 0.02). Intradialytic exercise with low intensity in the supine position attenuated ultrafiltration-induced BV reduction at the end of HD. Therefore, intradialytic exercise may prevent intradialytic hypotension during later HD, although its intensity was relatively low level. PMID:26720736

  17. Regulation of mTOR Pathway in Exercise-induced Cardiac Hypertrophy.

    PubMed

    Liao, J; Li, Y; Zeng, F; Wu, Y

    2015-05-01

    This study was designed to examine whether the mTOR signaling pathway would respond to long-term different intensity exercises and to observe the impact of exercise upon possible cardiac damage. Male Sprague Dawley rats were randomly divided into control group, moderate-intensity exercise group and high-intensity exercise group, and each exercise group had 4 observation time points (1-24 h). Exercise training lasted 8 weeks with a 2-day break for each week. Serum cTnI was measured by ELSIA and myocardium histology was assessed by HE and HBFP. The expressions of Akt, mTOR, p70(S6K) and their phosphorylated forms were determined by western-blot. Both exercises were effective at inducing cardiac hypertrophy, wherein magnitude increased with exercise intensity. The significantly high level of serum cTnI in the high-intensity group was accompanied by obvious myocellular abnormalities and ischemia in the myocardium. Significant activation of Akt, mTOR and p70(S6K) were observed in the moderate exercise group but not in the high-intensity exercise group. Results indicate that long-term high-intensity exercise training would induce cardiac hypertrophy accompanied by damage to the heart, entailing a risk of pathological changes. There might be a pivotal regulatory role of the mTOR signaling pathway on cardiac hypertrophy after long-term moderate exercise, but not after high-intensity exercise. PMID:25607521

  18. The effect of exercise-induced arousal on cognitive task performance: a meta-regression analysis.

    PubMed

    Lambourne, Kate; Tomporowski, Phillip

    2010-06-23

    The effects of acute exercise on cognitive performance were examined using meta-analytic techniques. The overall mean effect size was dependent on the timing of cognitive assessment. During exercise, cognitive task performance was impaired by a mean effect of -0.14. However, impairments were only observed during the first 20min of exercise. Otherwise, exercise-induced arousal enhanced performance on tasks that involved rapid decisions and automatized behaviors. Following exercise, cognitive task performance improved by a mean effect of 0.20. Arousal continued to facilitate speeded mental processes and also enhanced memory storage and retrieval. Positive effects were observed following exercise regardless of whether the study protocol was designed to measure the effects of steady-state exercise, fatiguing exercise, or the inverted-U hypothesis. Finally, cognitive performance was affected differentially by exercise mode. Cycling was associated with enhanced performance during and after exercise, whereas treadmill running led to impaired performance during exercise and a small improvement in performance following exercise. These results are indicative of the complex relation between exercise and cognition. Cognitive performance may be enhanced or impaired depending on when it is measured, the type of cognitive task selected, and the type of exercise performed. PMID:20381468

  19. Exerciser

    NASA Technical Reports Server (NTRS)

    Lem, J. D.

    1977-01-01

    The Mark I exerciser which was added for the second and third Skylab missions, was used for a number of arm and leg exercises. This unit is a modified version of a commercial device. This is an iso-kinetic, or constant velocity, exerciser which retards the speed at which the user is allowed to move. The user applies a maximum effort and the device automatically varies the opposing resistance to maintain speed of translation at a constant preselected value.

  20. Acute Biphasic Effects of Ayahuasca

    PubMed Central

    Schenberg, Eduardo Ekman; Alexandre, João Felipe Morel; Filev, Renato; Cravo, Andre Mascioli; Sato, João Ricardo; Muthukumaraswamy, Suresh D.; Yonamine, Maurício; Waguespack, Marian; Lomnicka, Izabela; Barker, Steven A.; da Silveira, Dartiu Xavier

    2015-01-01

    Ritual use of ayahuasca, an amazonian Amerindian medicine turned sacrament in syncretic religions in Brazil, is rapidly growing around the world. Because of this internationalization, a comprehensive understanding of the pharmacological mechanisms of action of the brew and the neural correlates of the modified states of consciousness it induces is important. Employing a combination of electroencephalogram (EEG) recordings and quantification of ayahuasca's compounds and their metabolites in the systemic circulation we found ayahuasca to induce a biphasic effect in the brain. This effect was composed of reduced power in the alpha band (8–13 Hz) after 50 minutes from ingestion of the brew and increased slow- and fast-gamma power (30–50 and 50–100 Hz, respectively) between 75 and 125 minutes. Alpha power reductions were mostly located at left parieto-occipital cortex, slow-gamma power increase was observed at left centro-parieto-occipital, left fronto-temporal and right frontal cortices while fast-gamma increases were significant at left centro-parieto-occipital, left fronto-temporal, right frontal and right parieto-occipital cortices. These effects were significantly associated with circulating levels of ayahuasca’s chemical compounds, mostly N,N-dimethyltryptamine (DMT), harmine, harmaline and tetrahydroharmine and some of their metabolites. An interpretation based on a cognitive and emotional framework relevant to the ritual use of ayahuasca, as well as it's potential therapeutic effects is offered. PMID:26421727

  1. Acute Biphasic Effects of Ayahuasca.

    PubMed

    Schenberg, Eduardo Ekman; Alexandre, João Felipe Morel; Filev, Renato; Cravo, Andre Mascioli; Sato, João Ricardo; Muthukumaraswamy, Suresh D; Yonamine, Maurício; Waguespack, Marian; Lomnicka, Izabela; Barker, Steven A; da Silveira, Dartiu Xavier

    2015-01-01

    Ritual use of ayahuasca, an amazonian Amerindian medicine turned sacrament in syncretic religions in Brazil, is rapidly growing around the world. Because of this internationalization, a comprehensive understanding of the pharmacological mechanisms of action of the brew and the neural correlates of the modified states of consciousness it induces is important. Employing a combination of electroencephalogram (EEG) recordings and quantification of ayahuasca's compounds and their metabolites in the systemic circulation we found ayahuasca to induce a biphasic effect in the brain. This effect was composed of reduced power in the alpha band (8-13 Hz) after 50 minutes from ingestion of the brew and increased slow- and fast-gamma power (30-50 and 50-100 Hz, respectively) between 75 and 125 minutes. Alpha power reductions were mostly located at left parieto-occipital cortex, slow-gamma power increase was observed at left centro-parieto-occipital, left fronto-temporal and right frontal cortices while fast-gamma increases were significant at left centro-parieto-occipital, left fronto-temporal, right frontal and right parieto-occipital cortices. These effects were significantly associated with circulating levels of ayahuasca's chemical compounds, mostly N,N-dimethyltryptamine (DMT), harmine, harmaline and tetrahydroharmine and some of their metabolites. An interpretation based on a cognitive and emotional framework relevant to the ritual use of ayahuasca, as well as it's potential therapeutic effects is offered. PMID:26421727

  2. Noninvasive profiling of exercise-induced hypoxemia in competitive cyclists.

    PubMed

    Siegler, Jason C; Robergs, Robert A; Faria, Eric W; Wyatt, Frank B; McCarthy, Jason

    2007-01-01

    The purpose of this case study was to profile maximal exercise and the incidence of exercise-induced arterial hypoxemia (EIAH) at three different altitudes within a group of competitive cyclists residing and training at 1,500 m. Ten male cyclists (category I or II professional road cyclists: ages, 27.7 +/- 6.1; weight, 69.9 +/- 6.9 kg) participated in three randomly assigned VO2max tests at sea level (SL), 1,500 m and 3000 m. Arterial saturation (pulse oximetry), ventilation, and power output (PO) were recorded continuously throughout the test. The SaO2 percentages at VO2max were significantly higher at SL when compared with 1500 m (p < 0.001); however, no difference was observed between VO2max values at either altitude (SL: 72.3 +/- 2.5 mL.kg-1.min-1, 1,500 m: 70.6 +/- 2.3 mL.kg-1.min-1), only when compared with 3,000 m: 63.9 +/- 2.1 mL.kg-1.min-1, p < 0.021. Percent SaO2 did correspond with maximal PO, and there was an overall main effect observed between POs as they continually declined from SL to 3,000 m (SL: 403.3 +/- 10.6 W; 1,500 m: 376.1 +/- 9.8 W; 3,000 m: 353.9 +/- 7.8 W; p < 0.0001). The results of this case study revealed that training and residing at 1,500 m did not reduce the incidence of EIAH during maximal exercise at 1,500 m for this selected group of cyclists. PMID:17365952

  3. Relationship between exercise induced elevation of left ventricular filling pressure and exercise intolerance in patients with atrial fibrillation

    PubMed Central

    Chen, Shao-Min; He, Rong; Li, Wei-Hong; Li, Zhao-Ping; Chen, Bao-Xia; Feng, Xin-Heng

    2016-01-01

    Background Elevated left ventricular filling pressure (LVFP) is an important cause of exercise intolerance in patients with atrial fibrillation (AF). Exercise stress echocardiography could assess LVFP during exercise. The objective of this study was to investigate the relationship between exercise induced elevation of LVFP and exercise capacity in patients with AF. Methods This study included 145 consecutive patients (81 men and 64 women; mean age 65.5 ± 8.0 years) with persistent non-valvular AF and normal left ventricular systolic function (left ventricular ejection fraction ≥ 50%). All patients underwent a symptom-limited cardiopulmonary exercise test (CPET). Doppler echocardiography was performed both at rest and immediately after exercise. Five consecutive measurements of early diastolic mitral inflow velocity (E) and early diastolic mitral annular velocity (e') were taken and averaged. E/e' ratio was calculated. Elevated LVFP was defined as E/e' > 9, and patients with elevated LVFP at rest were excluded. Results Patients were classified into two groups according to LVFP estimated by E/e' ratio after exercise: 39 (26.9%) with elevated LVFP after exercise and 106 (73.1%) with normal LVFP. As compared with patients with normal LVFP, the ones with elevated LVFP after exercise had significantly lower peak oxygen uptake (VO2 peak) (21.7 ± 2.3 vs. 26.4 ± 3.8 mL/min per kilogram, P < 0.001), lower anaerobic threshold (19.9 ± 2.5 vs. 26.0 ± 4.0 mL/min per kilogram, P < 0.001), and shorter exercise time duration (6.2 ± 0.8 vs. 7.0 ± 1.3 min, P < 0.001). Multivariate analysis showed that age, gender and E/e' after exercise were significantly correlated with VO2 peak. Conclusion Elevated LVFP estimated by E/e' ratio after exercise is independently associated with reduced exercise capacity in AF patients. PMID:27582773

  4. Resistance exercise, but not endurance exercise, induces IKKβ phosphorylation in human skeletal muscle of training-accustomed individuals.

    PubMed

    Møller, Andreas Buch; Vendelbo, Mikkel Holm; Rahbek, Stine Klejs; Clasen, Berthil Forrest; Schjerling, Peter; Vissing, Kristian; Jessen, Niels

    2013-12-01

    The mammalian target of rapamycin complex 1 (mTORC1) is considered an important role in the muscular adaptations to exercise. It has been proposed that exercise-induced signaling to mTORC1 do not require classic growth factor PI3K/Akt signaling. Activation of IKKβ and the mitogen-activated protein kinases (MAPKs) Erk1/2 and p38 has been suggested to link inflammation and cellular stress to activation of mTORC1 through the tuberous sclerosis 1 (TSC1)/tuberous sclerosis 2 (TSC2) complex. Consequently, activation of these proteins constitutes potential alternative mechanisms of mTORC1 activation following exercise. Previously, we demonstrated that mTOR is preferentially activated in response to resistance exercise compared to endurance exercise in trained individuals without concomitant activation of Akt. In the present study, we extended this investigation by examining IκB kinase complex (IKK), TSC1, MAPK, and upstream Akt activators, along with gene expression of selected cytokines, in skeletal muscles from these subjects. Biopsies were sampled prior to, immediately after, and in the recovery period following resistance exercise, endurance exercise, and control interventions. The major finding was that IKKβ phosphorylation increased exclusively after resistance exercise. No changes in TSC1, Erk1/2, insulin receptor, or insulin receptor substrate 1 phosphorylation were observed in any of the groups, while p38 phosphorylation was higher in the resistance exercise group compared to both other groups immediately after the intervention. Resistance and endurance exercise increased IL6, IL8, and TNFα gene expression immediately after exercise. The non-exercise control group demonstrated that cytokine gene expression is also sensitive to repeated biopsy sampling, whereas no effect of repeated biopsy sampling on protein expression and phosphorylation was observed. In conclusion, resistance exercise, but not endurance exercise, increases IKKβ phosphorylation in trained

  5. Area postrema-induced inhibition of the exercise pressor reflex.

    PubMed

    Bonigut, S; Bonham, A C; Stebbins, C L

    1997-04-01

    The exercise pressor reflex is opposed by the arterial baroreflex, and circulating peptides may act in the area postrema to enhance this inhibition. Therefore, we tested the hypothesis that the area postrema exerts an inhibitory effect on this reflex. Consequently, in six alpha-chloralose-anesthetized cats, blood pressure and heart rate responses to 30 s of electrically stimulated hindlimb contraction were compared before and after thermal coagulation of the area postrema. In six other cats, the same contraction-induced cardiovascular responses were assessed before and after chemical lesion of the area postrema using kainic acid (214 +/- 9 nl, 2.5-5 mM). Thermal lesion of the area postrema augmented blood pressure and heart rate responses to contraction from 29 +/- 5 to 47 +/- 7 mmHg (P < 0.05) and from 8 +/- 2 to 14 +/- 2 beats/min (P < 0.05), respectively. Chemical lesion of the area postrema enhanced contraction-evoked blood pressure (30 +/- 7 vs. 47 +/- 6 mmHg, P < 0.05) and heart rate (12 +/- 4 vs. 17 +/- 4 beats/min, P < 0.05) responses. These data suggest that the area postrema attenuates the exercise pressor reflex, possibly through the actions of circulating peptides on baroreflex function. PMID:9139947

  6. Improvement after training of children with exercise-induced asthma.

    PubMed

    Svenonius, E; Kautto, R; Arborelius, M

    1983-01-01

    Fifty children with exercise-induced asthma (EIA) volunteered to take part in a study of the influence of training on EIA. 1) Ten children did not change physical activity. 2) Twelve children trained after premedication with salbutamol inhalations. 3) Thirteen children trained after premedication with disodium chromoglicate (DSCG) and used that drug for treatment. 4) Fifteen children trained in their own regimen, commonly after premedication with salbutamol. Their training programme (groups 2-3) consisted of high load exercise periods of two minutes interrupted by intervals of rest for two minutes during 30 minutes followed by interval swimming for another 30 minutes, twice a week for 3-4 months. Before the training period the degree of EIA was tested with a battery of lung function tests before and after running for 6 minutes on a treadmill at heart rate 170. EIA after training was measured applying the same procedure. Cardiocirculatory performance was evaluated before and after training with work on a cycle ergometer and expressed as W/kg body weight at heart rate 170. The children in groups 2, 3 and 4 improved their physical working capacity by 11% (p less than 0.01), 21% and 11%, respectively, but no improvement was found in group 1. Significant improvements in EIA after the training periods were found in all training groups, but basal asthma improved most in group 3, probably due to the basal treatment with DSCG. PMID:6407276

  7. Familial Paroxysmal Exercise-Induced Dystonia: Atypical Presentation of Autosomal Dominant GTP-Cyclohydrolase 1 Deficiency

    ERIC Educational Resources Information Center

    Dale, Russell C.; Melchers, Anna; Fung, Victor S. C.; Grattan-Smith, Padraic; Houlden, Henry; Earl, John

    2010-01-01

    Paroxysmal exercise-induced dystonia (PED) is one of the rarer forms of paroxysmal dyskinesia, and can occur in sporadic or familial forms. We report a family (male index case, mother and maternal grandfather) with autosomal dominant inheritance of paroxysmal exercise-induced dystonia. The dystonia began in childhood and was only ever induced…

  8. Moyamoya disease presenting with paroxysmal exercise-induced dyskinesia.

    PubMed

    Lyoo, Chul Hyoung; Kim, Dong Joon; Chang, Hyuk; Lee, Myung Sik

    2007-10-01

    We report a patient with moyamoya disease presenting with paroxysmal exercise-induced dyskinesia (PED). A 31-year-old lathe man developed recurrent attacks of paroxysmal hemichorea. The attacks always affected his left limbs and occurred either after several hours of working or while playing football. The duration of attacks ranged from 30 min to 4h. Attacks were not provoked by sudden movements, consumption of coffee or alcohol, hyperventilation, emotional stress, exposure to cold or passive movement. An MRI of the brain showed no parenchymal lesions. However, (99m)Tc-ethylcysteine dimer SPECT study showed hypoperfusion in the right striatum. Digital subtraction angiography showed stenosis of the right internal carotid and middle cerebral artery with prominent basal collaterals, which was compatible with moyamoya disease. Imaging studies of the cerebral arteries should be done in patients with clinical features of PED in order to detect possible cases of moyamoya disease. PMID:16952479

  9. The Impact of Compact Layer in Biphasic Scaffold on Osteochondral Tissue Engineering

    PubMed Central

    Cheng, Jian-Hua; Zhou, Wei; Xiong, Zhuo; Mu, Yun-Jing; Liu, Jian

    2013-01-01

    The structure of an osteochondral biphasic scaffold is required to mimic native tissue, which owns a calcified layer associated with mechanical and separation function. The two phases of biphasic scaffold should possess efficient integration to provide chondrocytes and osteocytes with an independent living environment. In this study, a novel biphasic scaffold composed of a bony phase, chondral phase and compact layer was developed. The compact layer-free biphasic scaffold taken as control group was also fabricated. The purpose of current study was to evaluate the impact of the compact layer in the biphasic scaffold. Bony and chondral phases were seeded with autogeneic osteoblast- or chondrocyte-induced bone marrow stromal cells (BMSCs), respectively. The biphasic scaffolds-cells constructs were then implanted into osteochondral defects of rabbits’ knees, and the regenerated osteochondral tissue was evaluated at 3 and 6 months after surgery. Anti-tensile and anti-shear properties of the compact layer-containing biphasic scaffold were significantly higher than those of the compact layer-free biphasic scaffold in vitro. Furthermore, in vivo studies revealed superior macroscopic scores, glycosaminoglycan (GAG) and collagen content, micro tomograph imaging results, and histological properties of regenerated tissue in the compact layer-containing biphasic scaffold compared to the control group. These results indicated that the compact layer could significantly enhance the biomechanical properties of biphasic scaffold in vitro and regeneration of osteochondral tissue in vivo, and thus represented a promising approach to osteochondral tissue engineering. PMID:23382984

  10. Acute Calcium Ingestion Attenuates Exercise-induced Disruption of Calcium Homeostasis

    PubMed Central

    Barry, Daniel W; Hansen, Kent C; Van Pelt, Rachael E; Witten, Michael; Wolfe, Pamela; Kohrt, Wendy M

    2011-01-01

    Purpose Exercise is associated with a decrease in bone mineral density under certain conditions. One potential mechanism is increased bone resorption due to an exercise-induced increase in parathyroid hormone (PTH), possibly triggered by dermal calcium loss. The purpose of this investigation was to determine whether calcium supplementation either before or during exercise attenuates exercise-induced increases in PTH and C-terminal telopeptide of type I collagen (CTX; a marker of bone resorption). Methods Male endurance athletes (n=20) completed three 35-km cycling time trials under differing calcium supplementation conditions: 1) 1000 mg calcium 20 minutes before exercise and placebo during, 2) placebo before and 250 mg calcium every 15 minutes during exercise (1000 mg total), or 3) placebo before and during exercise. Calcium was delivered in a 1000 mg/L solution. Supplementation was double-blinded and trials were performed in random order. PTH, CTX, bone-specific alkaline phosphatase (BAP; a marker of bone formation), and ionized calcium (iCa) were measured before and immediately after exercise. Results CTX increased and iCa decreased similarly in response to exercise under all test conditions. When compared to placebo, calcium supplementation before exercise attenuated the increase in PTH (55.8 ± 15.0 vs. 74.0 ± 14.2; mean ± SE; p=0.04); there was a similar trend (58.0 ± 17.4; p=0.07) for calcium supplementation during exercise. There were no effects of calcium on changes in CTX, BAP, and iCa. Conclusions Calcium supplementation before exercise attenuated the disruption of PTH. Further research is needed to determine the effects of repeated increases in PTH and CTX on bone (i.e., exercise training), and whether calcium supplementation can diminish any exercise-induced demineralization. PMID:20798655

  11. Post-exercise alcohol ingestion exacerbates eccentric-exercise induced losses in performance.

    PubMed

    Barnes, Matthew J; Mündel, Toby; Stannard, Stephen R

    2010-03-01

    The effect of acute alcohol intake on muscular performance in both the exercising and non-exercising legs in the days following strenuous eccentric exercise was investigated to ascertain whether an interaction between post-exercise alcohol use and muscle damage causes an increase in damage-related weakness. Ten healthy males performed 300 maximal eccentric contractions of the quadriceps muscles of one leg on an isokinetic dynamometer. They then consumed either a beverage containing 1 g of ethanol per kg bodyweight ethanol (as vodka and orange juice; ALC) or a non-alcoholic beverage (OJ). At least 2 weeks later they performed an equivalent bout of eccentric exercise on the contralateral leg after which they consumed the other beverage. Measurement of peak and average peak isokinetic (concentric and eccentric) and isometric torque produced by the quadriceps of both exercising and non-exercising legs was made before and 36 and 60 h post-exercise. Greatest decreases in exercising leg performance were observed at 36 h with losses of 28.7, 31.9 and 25.9% occurring for OJ average peak isometric, concentric, and eccentric torques, respectively. However, average peak torque loss was significantly greater in ALC with the same performance measures decreasing by 40.9, 42.8 and 44.8% (all p < 0.05). Performance of the non-exercising leg did not change significantly under either treatment. Therefore, consumption of moderate amounts of alcohol after damaging exercise magnifies the loss of force associated with strenuous eccentric exercise. This weakness appears to be due to an interaction between muscle damage and alcohol rather than the systemic effects of acute alcohol consumption. PMID:20012446

  12. Exercise

    MedlinePlus

    ... article Exercise / physical activity with MS Judy Boone, physical therapist Lynn Williams, Dan Melfi and Dave Altman discuss ... adjusted as changes occur in MS symptoms. A physical therapist experienced with MS can be helpful in designing, ...

  13. Genetic variation and exercise-induced muscle damage: implications for athletic performance, injury and ageing.

    PubMed

    Baumert, Philipp; Lake, Mark J; Stewart, Claire E; Drust, Barry; Erskine, Robert M

    2016-09-01

    Prolonged unaccustomed exercise involving muscle lengthening (eccentric) actions can result in ultrastructural muscle disruption, impaired excitation-contraction coupling, inflammation and muscle protein degradation. This process is associated with delayed onset muscle soreness and is referred to as exercise-induced muscle damage. Although a certain amount of muscle damage may be necessary for adaptation to occur, excessive damage or inadequate recovery from exercise-induced muscle damage can increase injury risk, particularly in older individuals, who experience more damage and require longer to recover from muscle damaging exercise than younger adults. Furthermore, it is apparent that inter-individual variation exists in the response to exercise-induced muscle damage, and there is evidence that genetic variability may play a key role. Although this area of research is in its infancy, certain gene variations, or polymorphisms have been associated with exercise-induced muscle damage (i.e. individuals with certain genotypes experience greater muscle damage, and require longer recovery, following strenuous exercise). These polymorphisms include ACTN3 (R577X, rs1815739), TNF (-308 G>A, rs1800629), IL6 (-174 G>C, rs1800795), and IGF2 (ApaI, 17200 G>A, rs680). Knowing how someone is likely to respond to a particular type of exercise could help coaches/practitioners individualise the exercise training of their athletes/patients, thus maximising recovery and adaptation, while reducing overload-associated injury risk. The purpose of this review is to provide a critical analysis of the literature concerning gene polymorphisms associated with exercise-induced muscle damage, both in young and older individuals, and to highlight the potential mechanisms underpinning these associations, thus providing a better understanding of exercise-induced muscle damage. PMID:27294501

  14. Resistance exercise enhances the molecular signaling of mitochondrial biogenesis induced by endurance exercise in human skeletal muscle.

    PubMed

    Wang, Li; Mascher, Henrik; Psilander, Niklas; Blomstrand, Eva; Sahlin, Kent

    2011-11-01

    Combining endurance and strength training (concurrent training) may change the adaptation compared with single mode training. However, the site of interaction and the mechanisms are unclear. We have investigated the hypothesis that molecular signaling of mitochondrial biogenesis after endurance exercise is impaired by resistance exercise. Ten healthy subjects performed either only endurance exercise (E; 1-h cycling at ∼65% of maximal oxygen uptake), or endurance exercise followed by resistance exercise (ER; 1-h cycling + 6 sets of leg press at 70-80% of 1 repetition maximum) in a randomized cross-over design. Muscle biopsies were obtained before and after exercise (1 and 3 h postcycling). The mRNA of genes related to mitochondrial biogenesis [(peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-1)α, PGC-1-related coactivator (PRC)] related coactivator) and substrate regulation (pyruvate dehydrogenase kinase-4) increased after both E and ER, but the mRNA levels were about twofold higher after ER (P < 0.01). Phosphorylation of proteins involved in the signaling cascade of protein synthesis [mammalian target of rapamycin (mTOR), ribosomal S6 kinase 1, and eukaryotic elongation factor 2] was altered after ER but not after E. Moreover, ER induced a larger increase in mRNA of genes associated with positive mTOR signaling (cMyc and Rheb). Phosphorylation of AMP-activated protein kinase, acetyl-CoA carboxylase, and Akt increased similarly at 1 h postcycling (P < 0.01) after both types of exercise. Contrary to our hypothesis, the results demonstrate that ER, performed after E, amplifies the adaptive signaling response of mitochondrial biogenesis compared with single-mode endurance exercise. The mechanism may relate to a cross talk between signaling pathways mediated by mTOR. The results suggest that concurrent training may be beneficial for the adaptation of muscle oxidative capacity. PMID:21836044

  15. The 5-HT3 receptor is essential for exercise-induced hippocampal neurogenesis and antidepressant effects.

    PubMed

    Kondo, M; Nakamura, Y; Ishida, Y; Shimada, S

    2015-11-01

    Exercise has a variety of beneficial effects on brain structure and function, such as hippocampal neurogenesis, mood and memory. Previous studies have shown that exercise enhances hippocampal neurogenesis, induces antidepressant effects and improves learning behavior. Brain serotonin (5-hydroxytryptamine, 5-HT) levels increase following exercise, and the 5-HT system has been suggested to have an important role in these exercise-induced neuronal effects. However, the precise mechanism remains unclear. In this study, analysis of the 5-HT type 3A receptor subunit-deficient (htr3a(-/-)) mice revealed that lack of the 5-HT type 3 (5-HT3) receptor resulted in loss of exercise-induced hippocampal neurogenesis and antidepressant effects, but not of learning enhancement. Furthermore, stimulation of the 5-HT3 receptor promoted neurogenesis. These findings demonstrate that the 5-HT3 receptor is the critical target of 5-HT action in the brain following exercise, and is indispensable for hippocampal neurogenesis and antidepressant effects induced by exercise. This is the first report of a pivotal 5-HT receptor subtype that has a fundamental role in exercise-induced morphological changes and psychological effects. PMID:25403840

  16. Effect of exercise intensity on mild rhythmic-handgrip-exercise-induced functional sympatholysis.

    PubMed

    Watanabe, Hitoshi; Watanabe, Kanji; Wadazumi, Tsuyoshi; Yoneyama, Fujiko

    2007-11-01

    This study attempts to clarify whether intensity of exercise influences functional sympatholysis during mild rhythmic handgrip exercise (RHG). We measured muscle oxygenation in both exercising and non-exercising muscle in the same arm in 11 subjects using near infrared spectroscopy (NIRS), heart rate, and blood pressure. We used the total labile signal to assess the relative muscle oxygenation by occlusion for 6 min. Subjects performed RHG (20 times/min) for 6 min at 10%, 20%, and 30% of maximal voluntary contraction (MVC) at random. We used a non-hypotensive lower body negative pressure (LBNP) of 220 mmHg for 2 min to elicit reproducible enhancement in muscle sympathetic nerve activity (MSNA) at rest and during RHG. LBNP caused decreases of 16.4% and 17.7% of the level of muscle oxygenation at rest (pre) in exercising (forearm) and non-exercising (upper arm) muscle respectively. Muscle oxygenation in non-exercising muscle with the application of LBNP during RHG did not change significantly at each intensity. In contrast, the decrease in muscle oxygenation in exercising muscle attenuated progressively as exercise intensity increased (10% MVC 8.8+/-2.8%, 20% MVC 7.1+/-2.0%, 30% MVC 4.6+/-3.0%), when LBNP was applied during RHG. The attenuation of the decrease in muscle oxygenation due to LBNP during RHG at 10%, 20%, and 30% was significantly different from that at rest (p<0.01). These findings indicate that functional sympatholysis during mild RHG might be attributed to exercise intensity. PMID:18174667

  17. Effects of grape seed extract supplementation on exercise-induced oxidative stress in rats.

    PubMed

    Belviranlı, Muaz; Gökbel, Hakkı; Okudan, Nilsel; Başaralı, Kemal

    2012-07-01

    The aim of the present study was to investigate the effects of grape seed extract (GSE) supplementation on exercise performance and oxidative stress in acutely and chronically exercised rats. A total of sixty-four male rats were used in the study. Rats were divided into six groups: control, chronic exercise control, acute exercise control (AEC), GSE-supplemented control, GSE-supplemented chronic exercise and GSE-supplemented acute exercise groups. Chronic exercise consisted of treadmill running at 25 m/min, 45 min/d, 5 d a week for 6 weeks. Rats in the acute exercise groups were run on the treadmill at 30 m/min until exhaustion. GSE were given at 100 mg/kg of body weight with drinking water for 6 weeks. Plasma was separated from blood samples for the analysis of oxidative stress markers. There was no significant difference in time of exhaustion between the acute exercise groups. Plasma malondialdehyde (MDA) levels were higher in the acute exercise groups and lower in the chronic exercise groups. GSE supplementation decreased MDA levels. Xanthine oxidase and adenosine deaminase activities were higher in the AEC group compared to all the other groups. NO levels were increased with both chronic exercise and GSE supplementation. Superoxide dismutase and glutathione peroxidase activities were lower in the acute exercised groups and higher in the chronic exercised groups. GSE supplementation caused an increase in antioxidant enzyme activities. In conclusion, GSE supplementation prevents exercise-induced oxidative stress by preventing lipid peroxidation and increasing antioxidant enzyme activities. PMID:22011589

  18. Exercise protects against PCB-induced inflammation and associated cardiovascular risk factors.

    PubMed

    Murphy, Margaret O; Petriello, Michael C; Han, Sung Gu; Sunkara, Manjula; Morris, Andrew J; Esser, Karyn; Hennig, Bernhard

    2016-02-01

    Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that contribute to the initiation of cardiovascular disease. Exercise has been shown to reduce the risk of cardiovascular disease; however, whether exercise can modulate PCB-induced vascular endothelial dysfunction and associated cardiovascular risk factors is unknown. We examined the effects of exercise on coplanar PCB-induced cardiovascular risk factors including oxidative stress, inflammation, impaired glucose tolerance, hypercholesteremia, and endothelium-dependent relaxation. Male ApoE(-/-) mice were divided into sedentary and exercise groups (voluntary wheel running) over a 12-week period. Half of each group was exposed to vehicle or PCB 77 at weeks 1, 2, 9, and 10. For ex vivo studies, male C57BL/6 mice exercised via voluntary wheel training for 5 weeks and then were administered with vehicle or PCB 77 24 h before vascular reactivity studies were performed. Exposure to coplanar PCB increased risk factors associated with cardiovascular disease, including oxidative stress and systemic inflammation, glucose intolerance, and hypercholesteremia. The 12-week exercise intervention significantly reduced these proatherogenic parameters. Exercise also upregulated antioxidant enzymes including phase II detoxification enzymes. Sedentary animals exposed to PCB 77 exhibited endothelial dysfunction as demonstrated by significant impairment of endothelium-dependent relaxation, which was prevented by exercise. Lifestyle modifications such as aerobic exercise could be utilized as a therapeutic approach for the prevention of adverse cardiovascular health effects induced by environmental pollutants such as PCBs. PMID:25586614

  19. Hyperthermia, dehydration, and osmotic stress: unconventional sources of exercise-induced reactive oxygen species.

    PubMed

    King, Michelle A; Clanton, Thomas L; Laitano, Orlando

    2016-01-15

    Evidence of increased reactive oxygen species (ROS) production is observed in the circulation during exercise in humans. This is exacerbated at elevated body temperatures and attenuated when normal exercise-induced body temperature elevations are suppressed. Why ROS production during exercise is temperature dependent is entirely unknown. This review covers the human exercise studies to date that provide evidence that oxidant and antioxidant changes observed in the blood during exercise are dependent on temperature and fluid balance. We then address possible mechanisms linking exercise with these variables that include shear stress, effects of hemoconcentration, and signaling pathways involving muscle osmoregulation. Since pathways of muscle osmoregulation are rarely discussed in this context, we provide a brief review of what is currently known and unknown about muscle osmoregulation and how it may be linked to oxidant production in exercise and hyperthermia. Both the circulation and the exercising muscle fibers become concentrated with osmolytes during exercise in the heat, resulting in a competition for available water across the muscle sarcolemma and other tissues. We conclude that though multiple mechanisms may be responsible for the changes in oxidant/antioxidant balance in the blood during exercise, a strong case can be made that a significant component of ROS produced during some forms of exercise reflect requirements of adapting to osmotic challenges, hyperthermia challenges, and loss of circulating fluid volume. PMID:26561649

  20. The regulation of autophagy during exercise in skeletal muscle.

    PubMed

    Vainshtein, Anna; Hood, David A

    2016-03-15

    The merits of exercise on muscle health and well-being are numerous and well documented. However, the mechanisms underlying the robust adaptations induced by exercise, particularly on mitochondria, are less clear and much sought after. Recently, an evolutionary conserved cellular recycling mechanism known as autophagy has been implicated in the adaptations to acute and chronic exercise. A basal level of autophagy is constantly ongoing in cells and tissues, ensuring cellular clearance and energy homeostasis. This pathway can be further induced, as a survival mechanism, by cellular perturbations, such as energetic imbalance and oxidative stress. During exercise, a biphasic autophagy response is mobilized, leading to both an acute induction and a long-term potentiation of the process. Posttranslational modifications arising from upstream signaling cascades induce an acute autophagic response during a single bout of exercise by mobilizing core autophagy machinery. A transcriptional program involving the regulators Forkhead box O, transcription factor EB, p53, and peroxisome proliferator coactivator-1α is also induced to fuel sustained increases in autophagic capacity. Autophagy has also been documented to mediate chronic exercise-induced metabolic benefits, and animal models in which autophagy is perturbed do not adapt to exercise to the same extent. In this review, we discuss recent developments in the field of autophagy and exercise. We specifically highlight the molecular mechanisms activated during acute exercise that lead to a prolonged adaptive response. PMID:26679612

  1. [Silent myocardial ischemia and exercise-induced arrhythmia detected by the exercise test in the total health promotion plan (THP)].

    PubMed

    Iwane, M; Shibe, Y; Itoh, K; Kinoshita, F; Kanagawa, Y; Kobayashi, M; Mugitani, K; Ohta, M; Ohata, H; Yoshikawa, A; Ikuta, Z; Nakamura, Y; Mohara, O

    2001-03-01

    We investigated the prevalence and characteristics of ischemic heart disease especially silent myocardial ischemia (SMI) and arrhythmia in need of careful observation in the exercise stress tests in the Total Health Promotion Plan (THP), which was conducted between 1994-96 for the purpose of measuring cardiopulmonary function. All workers (n = 4,918, 4,426 males) aged 18-60 yr old in an occupational field were studied. Exercise tests with an ergometer were performed by the LOPS protocol, in which the maximal workload was set up as a presumed 70-80% maximal oxygen intake, or STEP (original multistage protocol). ECG changes were evaluated with a CC5 lead. Two hundred and fifteen people refused the study because of a common cold, lumbago and so on. Of 4,703 subjects, 17 with abnormal rest ECG and 19 with probable anginal pain were excluded from the exercise tests. Of 4,667 who underwent the exercise test, 37 (0.79%) had ischemic ECG change, and 155 (3.32%) had striking arrhythmia. These 228 subjects then did a treadmill exercise test with Bruce protocol. Twenty-two (0.47% of 4,703) showed positive ECG change, 9 (0.19%) of 22 had abnormal findings on a 201Tl scan. 8 (0.17%) were diagnosed as SMI (Cohn I), in which the prevalence of hypertension, hyperlipidemia, diabetes mellitus, smoker and positive familial history of ischemic heart disease was greater than that of all subjects. In a 15-30 month follow up, none has developed cardiac accidents. Exercise-induced arrhythmia was detected in 11 (0.23%) subjects. Four were non-sustained ventricular tachycardia without any organic disease, 4 were ventricular arrhythmia based on cardiomyopathy detected by echocardiography, 2 were atrial fibrillation and another was WPW syndrome. It is therefore likely that the ergometer exercise test in THP was effective in preventing sudden death caused by ischemic heart disease or striking arrhythmia. PMID:11329953

  2. Exercise preconditioning attenuates pressure overload-induced pathological cardiac hypertrophy

    PubMed Central

    Xu, Tongyi; Tang, Hao; Zhang, Ben; Cai, Chengliang; Liu, Xiaohong; Han, Qingqi; Zou, Liangjian

    2015-01-01

    Pathological cardiac hypertrophy, a common response of the heart to a variety of cardiovascular diseases, is typically associated with myocytes remodeling and fibrotic replacement, cardiac dysfunction. Exercise preconditioning (EP) increases the myocardial mechanical load and enhances tolerance of cardiac ischemia-reperfusion injury (IRI), however, is less reported in pathological cardiac hypertrophy. To determine the effect of EP in pathological cardiac hypertrophy, Male 10-wk-old Sprague-Dawley rats (n=30) were subjected to 4 weeks of EP followed by 4-8 weeks of pressure overload (transverse aortic constriction, TAC) to induce pathological remodeling. TAC in untrained controls (n=30) led to pathological cardiac hypertrophy, depressed systolic function. We observed that left ventricular wall thickness in end diastole, heart size, heart weight-to-body weight ratio, heart weight-to-tibia length ratio, cross-sectional area of cardiomyocytes and the reactivation of fetal genes (atrial natriuretic peptide and brain natriuretic peptide) were markedly increased, meanwhile left ventricular internal dimension at end-diastole, systolic function were significantly decreased by TAC at 4 wks after operation (P < 0.01), all of which were effectively inhibited by EP treatment (P < 0.05), but the differences of these parameters were decreased at 8 wks after operation. Furthermore, EP treatment inhibited degradation of IκBα, and decreased NF-κB p65 subunit levels in the nuclear fraction, and then reduced IL2 levels in the myocardium of rats subject to TAC. EP can effectively attenuate pathological cardiac hypertrophic responses induced by TAC possibly through inhibition of degradation of IκB and blockade of the NF-κB signaling pathway in the early stage of pathological cardiac hypertrophy. PMID:25755743

  3. Psychological influences predict recovery following exercise induced shoulder pain.

    PubMed

    Parr, J; Borsa, P; Fillingim, R; Kaiser, K; Tillman, M D; Manini, T M; Gregory, C; George, S

    2014-03-01

    Predicting recovery following muscle injury can be difficult because it involves consideration of multiple factors. Our objective was to determine if psychological factors, sex, and peak pain and disability ratings could be predictive of delayed recovery following induced muscle injury. Healthy untrained volunteers (n=126; M:F 51:75) underwent a concentric/eccentric isokinetic exercise protocol on their dominant shoulder to induce fatigue, with individuals who reported pain (>0/10) at 96 h being classified as "not recovered". Individuals experiencing pain at 48 h were more likely not to be recovered (O.R.=1.62, p<0.001). Additionally, individuals with higher scores in pain catastrophizing at 48 h were more likely to experience pain at 96 h (O.R.=1.06, p<0.001). Pain duration (in days) was associated with pain scores at 48 h (β=0.385, p<0.001) and baseline anxiety (β=0.220, p=0.007). Fear of movement/re-injury at 96 h was found to be associated with pain catastrophizing at 48 h (β=0.537, p<0.001) and baseline levels of fear of pain (β=0.217, p=0.004). This study provides preliminary evidence that higher pain levels and pain catastrophizing following acute muscle injury are associated with poor recovery, higher fear of movement/re-injury and longer pain duration. PMID:24022571

  4. Exercise training-induced Regulation of Mitochondrial Quality

    PubMed Central

    Yan, Zhen; Lira, Vitor A.; Greene, Nicholas P.

    2012-01-01

    Mitochondria are dynamic organelles in skeletal muscle critical in physical performance and disease. The mitochondrial life cycle spans biogenesis, maintenance, and clearance. Exercise training may promote each of these processes, conferring positive impacts on skeletal muscle contractile and metabolic functions. This review focuses on the regulation of these processes by endurance exercise and discusses potential benefits in health and disease. PMID:22732425

  5. Deconditioning-induced exercise responses as influenced by heat acclimation

    NASA Technical Reports Server (NTRS)

    Shvartz, E.; Bhattacharya, A.; Sperinde, S. J.; Brock, P. J.; Sciaraffa, D.; Haines, R. F.; Greenleaf, J. E.

    1979-01-01

    A study to determine the effect of heat acclimation and physical training in temperate conditions on changes in exercise tolerance following water-immersion deconditioning is presented. Five young men were tested on a bicycle ergometer before and after heat acclimation and after water immersion. The subjects and the experimental procedure, heat acclimation and exercise training, water immersion, and exercise tolerance are discussed. Heat acclimation resulted in the usual decreases in exercise heart rate and rectal temperature and an increase in sweat rate. Water immersion resulted in substantial diuresis despite water consumed. The results show that heat acclimation provides an effective method of preventing the adverse effects of water-immersion deconditioning on exercise tolerance.

  6. Protective Role of Aerobic Exercise Against Cisplatin-Induced Nephrotoxicity in Rats

    PubMed Central

    Zeynali, Farzaneh; Nematbakhsh, Mehdi; Mojtahedi, Hossain; Poorshahnazari, Aliasghar; Talebi, Ardeshir; Pezeshki, Zahra; Mazaheri, Safoora; Moslemi, Fatemeh

    2015-01-01

    Background: Cisplatin (CP) is a chemotherapy drug and nephrotoxicity is considered as its major side effect. Aerobic exercise is well known as an approach to reduce the side effects of many drugs. Objectives: This study was designed to determine the protective role of aerobic exercise against CP-induced nephrotoxicity. Materials and Methods: Thirty male Wistar rats were randomly divided into four groups. Group I had aerobic exercise on a treadmill one hour per day and five days per week for eight weeks. Then, the exercise protocol was continued for another week, but during this week, the animals also received CP (2.5 mg/kg/day; ip). Group II underwent the same protocol as group I without exercise in the last week during the CP therapy. Groups III and IV were assigned as positive and negative control groups, and were treated with CP and saline without exercise, respectively. Finally, the animals were sacrificed for the biochemical measurement and tissue histopathology investigation. Results: CP alone without exercise increased serum levels of blood urea nitrogen (BUN), creatinine (Cr), and malondialdehyde (MDA); and kidney nitrite level, while treadmill exercise in group I significantly ameliorated these parameters (P < 0.05). Kidney and serum levels of MDA and nitrite did not alter significantly. Also, the severity of kidney tissue damage decreased significantly in groups I and II (P < 0.05). Conclusions: Aerobic exercise may reduce CP-induced nephrotoxicity with a favorable effect on renal function by increasing activation of antioxidant system. PMID:26448855

  7. Aerobic exercise protects retinal function and structure from light-induced retinal degeneration.

    PubMed

    Lawson, Eric C; Han, Moon K; Sellers, Jana T; Chrenek, Micah A; Hanif, Adam; Gogniat, Marissa A; Boatright, Jeffrey H; Pardue, Machelle T

    2014-02-12

    Aerobic exercise is a common intervention for rehabilitation of motor, and more recently, cognitive function (Intlekofer and Cotman, 2013; Wood et al., 2012). While the underlying mechanisms are complex, BDNF may mediate much of the beneficial effects of exercise to these neurons (Ploughman et al., 2007; Griffin et al., 2011; Real et al., 2013). We studied the effects of aerobic exercise on retinal neurons undergoing degeneration. We exercised wild-type BALB/c mice on a treadmill (10 m/min for 1 h) for 5 d/week or placed control mice on static treadmills. After 2 weeks of exercise, mice were exposed to either toxic bright light (10,000 lux) for 4 h to induce photoreceptor degeneration or maintenance dim light (25 lux). Bright light caused 75% loss of both retinal function and photoreceptor numbers. However, exercised mice exposed to bright light had 2 times greater retinal function and photoreceptor nuclei than inactive mice exposed to bright light. In addition, exercise increased retinal BDNF protein levels by 20% compared with inactive mice. Systemic injections of a BDNF tropomyosin-receptor-kinase (TrkB) receptor antagonist reduced retinal function and photoreceptor nuclei counts in exercised mice to inactive levels, effectively blocking the protective effects seen with aerobic exercise. The data suggest that aerobic exercise is neuroprotective for retinal degeneration and that this effect is mediated by BDNF signaling. PMID:24523530

  8. Exercise-induced ventricular arrhythmias in congestive heart failure and role of ACE inhibitors.

    PubMed

    Hasija, P K; Karloopia, S D; Shahi, B N; Chauhan, S S

    1998-02-01

    Ventricular arrhythmias are considered to be related to left ventricular (LV) dysfunction. ACE inhibitors though improve LV function their beneficial role on exercise-induced ventricular arrhythmias is not established. To study the effects of ACE inhibitors on exercise capacity vis-a-vis their role on exercise-induced ventricular arrhythmias, 25 patients of congestive heart failure (CHF) of various etiologies in NYHA Class II and III were subjected to a prospective randomised controlled trial. The control group comprising of 12 patients received conventional treatment (digitalis and diuretics) and the test group was given enalapril/captopril in addition as tolerated. They were followed up for 3 months. Exercise testing on treadmill and monitoring of clinical and biochemical parameters were done at the beginning and end of study in all cases. Ventricular arrhythmias observed during exercise and post-exercise for 10 minutes was analysed using Lown's grading for frequency and severity of ventricular arrhythmia. The mean exercise duration showed significant improvement on ACE inhibitor as compared to the control group (p < 0.05) however there was no significant change in the grades of arrhythmia. Serum electrolytes and other bio-chemical parameter were within normal range. It is concluded that effect of ACE inhibitor on improving functional capacity in CHF is independent of it's any effect on exercise-induced ventricular arrhythmias. PMID:11273109

  9. Pathophysiological mechanisms of exercise-induced anaphylaxis: an EAACI position statement.

    PubMed

    Ansley, L; Bonini, M; Delgado, L; Del Giacco, S; Du Toit, G; Khaitov, M; Kurowski, M; Hull, J H; Moreira, A; Robson-Ansley, P J

    2015-10-01

    This document is the result of a consensus on the mechanisms of exercise-induced anaphylaxis (EIAn), an unpredictable and potentially fatal syndrome. A multidisciplinary panel of experts including exercise physiologists, allergists, lung physicians, paediatricians and a biostatistician reached the given consensus. Exercise-induced anaphylaxis (EIAn) describes a rare and potentially fatal syndrome in which anaphylaxis occurs in conjunction with exercise. The pathophysiological mechanisms underlying EIAn have not yet been elucidated although a number of hypotheses have been proposed. This review evaluates the validity of each of the popular theories in relation to exercise physiology and immunology. On the basis of this evidence, it is concluded that proposed mechanisms lack validity, and it is recommended that a global research network is developed with a common approach to the diagnosis and treatment of EIAn in order to gain sufficient power for scientific evaluation. PMID:26100553

  10. Exercise-induced oxidatively damaged DNA in humans: evaluation in plasma or urine?

    PubMed

    Karpouzi, Christina; Nikolaidis, Stefanos; Kabasakalis, Athanasios; Tsalis, George; Mougios, Vassilis

    2016-01-01

    Physical exercise can induce oxidative damage in humans. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) is a widely known biomarker of DNA oxidation, which can be determined in blood and urine. The aim of the present study was to compare these two biological fluids in terms of which is more suitable for the estimation of the oxidative damage of DNA by measuring the concentration of 8-OHdG one hour after maximal exercise by enzyme immunoassay. The concentration of 8-OHdG increased with exercise only in plasma (p < 0.001), and values differed between exercise tests in both plasma and urine (p < 0.05). In conclusion, plasma appears to be more sensitive to exercise-induced 8-OHdG changes than urine and, hence, a more appropriate medium for assessing oxidative damage of DNA, although the poor repeatability of the measurement needs to be addressed in future studies. PMID:26849281

  11. The Impaired Function of Macrophages Induced by Strenuous Exercise Could Not Be Ameliorated by BCAA Supplementation.

    PubMed

    Xiao, Weihua; Chen, Peijie; Liu, Xiaoguang; Zhao, Linlin

    2015-10-01

    The aim of this study was to evaluate the effect of strenuous exercise on the functions of peritoneal macrophages in rats and to test the hypothesis that branched-chain amino acid (BCAA) supplementation will be beneficial to the macrophages of rats from strenuous exercise. Forty male Wistar rats were randomly divided into five groups: (C) Control, E) Exercise, (E1) Exercise with one week to recover, (ES) Exercise + Supplementation and (ES1) Exercise + Supplementation with 1 week to recover. All rats except those of the sedentary control were subjected to four weeks of strenuous exercise. Blood hemoglobin, serum testosterone and BCAA levels were tested. Peritoneal macrophages functions were also determined at the same time. The data showed that hemoglobin, testosterone, BCAA levels, and body weight in group E decreased significantly as compared with that of group C. Meanwhile, phagocytosis capacity (decreased by 17.07%, p = 0.031), reactive oxygen species (ROS) production (decreased by 26%, p = 0.003) and MHC II mRNA (decreased by 22%, p = 0.041) of macrophages decreased in the strenuous exercise group as compared with group C. However, the chemotaxis of macrophages did not change significantly. In addition, BCAA supplementation could slightly increase the serum BCAA levels of rats from strenuous exercise (increased by 6.70%, p > 0.05). Moreover, the body weight, the blood hemoglobin, the serum testosterone and the function of peritoneal macrophages in group ES did not change significantly as compared with group E. These results suggest that long-term intensive exercise impairs the function of macrophages, which is essential for microbicidal capability. This may represent a novel mechanism of immunosuppression induced by strenuous exercise. Moreover, the impaired function of macrophage induced by strenuous exercise could not be ameliorated by BCAA supplementation in the dosing and timing used for this study. PMID:26506374

  12. The Impaired Function of Macrophages Induced by Strenuous Exercise Could Not Be Ameliorated by BCAA Supplementation

    PubMed Central

    Xiao, Weihua; Chen, Peijie; Liu, Xiaoguang; Zhao, Linlin

    2015-01-01

    The aim of this study was to evaluate the effect of strenuous exercise on the functions of peritoneal macrophages in rats and to test the hypothesis that branched-chain amino acid (BCAA) supplementation will be beneficial to the macrophages of rats from strenuous exercise. Forty male Wistar rats were randomly divided into five groups: (C) Control, E) Exercise, (E1) Exercise with one week to recover, (ES) Exercise + Supplementation and (ES1) Exercise + Supplementation with 1 week to recover. All rats except those of the sedentary control were subjected to four weeks of strenuous exercise. Blood hemoglobin, serum testosterone and BCAA levels were tested. Peritoneal macrophages functions were also determined at the same time. The data showed that hemoglobin, testosterone, BCAA levels, and body weight in group E decreased significantly as compared with that of group C. Meanwhile, phagocytosis capacity (decreased by 17.07%, p = 0.031), reactive oxygen species (ROS) production (decreased by 26%, p = 0.003) and MHC II mRNA (decreased by 22%, p = 0.041) of macrophages decreased in the strenuous exercise group as compared with group C. However, the chemotaxis of macrophages did not change significantly. In addition, BCAA supplementation could slightly increase the serum BCAA levels of rats from strenuous exercise (increased by 6.70%, p > 0.05). Moreover, the body weight, the blood hemoglobin, the serum testosterone and the function of peritoneal macrophages in group ES did not change significantly as compared with group E. These results suggest that long-term intensive exercise impairs the function of macrophages, which is essential for microbicidal capability. This may represent a novel mechanism of immunosuppression induced by strenuous exercise. Moreover, the impaired function of macrophage induced by strenuous exercise could not be ameliorated by BCAA supplementation in the dosing and timing used for this study. PMID:26506374

  13. Role of PGC-1α during acute exercise-induced autophagy and mitophagy in skeletal muscle

    PubMed Central

    Vainshtein, Anna; Tryon, Liam D.; Pauly, Marion

    2015-01-01

    Regular exercise leads to systemic metabolic benefits, which require remodeling of energy resources in skeletal muscle. During acute exercise, the increase in energy demands initiate mitochondrial biogenesis, orchestrated by the transcriptional coactivator peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). Much less is known about the degradation of mitochondria following exercise, although new evidence implicates a cellular recycling mechanism, autophagy/mitophagy, in exercise-induced adaptations. How mitophagy is activated and what role PGC-1α plays in this process during exercise have yet to be evaluated. Thus we investigated autophagy/mitophagy in muscle immediately following an acute bout of exercise or 90 min following exercise in wild-type (WT) and PGC-1α knockout (KO) animals. Deletion of PGC-1α resulted in a 40% decrease in mitochondrial content, as well as a 25% decline in running performance, which was accompanied by severe acidosis in KO animals, indicating metabolic distress. Exercise induced significant increases in gene transcripts of various mitochondrial (e.g., cytochrome oxidase subunit IV and mitochondrial transcription factor A) and autophagy-related (e.g., p62 and light chain 3) genes in WT, but not KO, animals. Exercise also resulted in enhanced targeting of mitochondria for mitophagy, as well as increased autophagy and mitophagy flux, in WT animals. This effect was attenuated in the absence of PGC-1α. We also identified Niemann-Pick C1, a transmembrane protein involved in lysosomal lipid trafficking, as a target of PGC-1α that is induced with exercise. These results suggest that mitochondrial turnover is increased following exercise and that this effect is at least in part coordinated by PGC-1α. Anna Vainshtein received the AJP-Cell 2015 Paper of the Year award. Listen to a podcast with Anna Vainshtein and coauthor David A. Hood at http://ajpcell.podbean.com/e/ajp-cell-paper-of-the-year-2015-award-podcast/. PMID

  14. PGC-1α promotes exercise-induced autophagy in mouse skeletal muscle.

    PubMed

    Halling, Jens F; Ringholm, Stine; Nielsen, Maja M; Overby, Peter; Pilegaard, Henriette

    2016-02-01

    Recent evidence suggests that exercise stimulates the degradation of cellular components in skeletal muscle through activation of autophagy, but the time course of the autophagy response during recovery from exercise has not been determined. Furthermore, the regulatory mechanisms behind exercise-induced autophagy remain unclear, although the muscle oxidative phenotype has been linked with basal autophagy levels. Therefore, the aim of this study was to investigate the role of the key regulator of muscle oxidative capacity, PGC-1α, in exercise-induced autophagy at several time points during recovery. Mice with transgenic muscle-specific overexpression (TG) or knockout (MKO) of PGC-1α and their respective littermate controls were subjected to a single 1 h bout of treadmill running and euthanized immediately (0 h), 2, 6, and 10 h after exercise. In the PGC-1α MKO strain, quadriceps protein content of the autophagy marker LC3II was increased from 2 h into recovery in lox/lox control, but not in MKO mice. In the PGC-1α TG strain, quadriceps protein content of LC3II was increased from 2 h after exercise in TG, but not in WT. Although AMPK and ACC phosphorylation was increased immediately following exercise, the observed exercise-induced autophagy response was not associated with phosphorylation of the AMPK-target ULK1. However, lower protein carbonyl content was observed in lox/lox and TG mice after exercise coinciding with the increased LC3 lipidation. In conclusion, the present results suggest a role of skeletal muscle PGC-1α in coordinating several exercise-induced adaptive responses including autophagic removal of damaged cellular components. PMID:26869683

  15. Role of creatine supplementation in exercise-induced muscle damage: A mini review.

    PubMed

    Kim, Jooyoung; Lee, Joohyung; Kim, Seungho; Yoon, Daeyoung; Kim, Jieun; Sung, Dong Jun

    2015-10-01

    Muscle damage is induced by both high-intensity resistance and endurance exercise. Creatine is a widely used dietary supplement to improve exercise performance by reducing exercise-induced muscle damage. Many researchers have suggested that taking creatine reduces muscle damage by decreasing the inflammatory response and oxidative stress, regulating calcium homeostasis, and activating satellite cells. However, the underlying mechanisms of creatine and muscle damage have not been clarified. Therefore, this review discusses the regulatory effects of creatine on muscle damage by compiling the information collected from basic science and sports science research. PMID:26535213

  16. Treadmill exercise alleviates chronic mild stress-induced depression in rats

    PubMed Central

    Lee, Taeck-Hyun; Kim, Kijeong; Shin, Mal-Soon; Kim, Chang-Ju; Lim, Baek-Vin

    2015-01-01

    Depression is a major cause of disability and one of the most common public health problems. In the present study, antidepressive effect of treadmill exercise on chronic mild stress (CMS)-induced depression in rats was investigated. For this, sucrose intake test, immunohistochemistry for 5-bromo-2′-deoxyuridine, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining, and Western blot analysis for brain-derived neurotrophic factor, cyclic adenosine monophosphate response element binding protein, and endothelial nitric oxide synthase were conducted. Following adaptation to the animal vivarium and two baseline fluid intake tests, the animals were divided into four groups: the control group, the CMS-induced depression group, the CMS-induced depression and exercise group, and the CMS-induced depression and fluoxetine-treated group. The animals in the CMS groups were exposed to the CMS conditions for 8 weeks and those in the control group were exposed to the control conditions for 8 weeks. After 4 weeks of CMS, the rats in the CMS-induced depression and exercise group were made to run on a motorized treadmill for 30 min once a day for 4 weeks. In the present results, treadmill exercise alleviated CMS-induced depressive symptoms. Treadmill exercise restored sucrose consumption, increased cell proliferation, and decreased apoptotic cell death. The present results suggest the possibility that exercise may improve symptoms of depression. PMID:26730380

  17. Treadmill exercise alleviates chronic mild stress-induced depression in rats.

    PubMed

    Lee, Taeck-Hyun; Kim, Kijeong; Shin, Mal-Soon; Kim, Chang-Ju; Lim, Baek-Vin

    2015-12-01

    Depression is a major cause of disability and one of the most common public health problems. In the present study, antidepressive effect of treadmill exercise on chronic mild stress (CMS)-induced depression in rats was investigated. For this, sucrose intake test, immunohistochemistry for 5-bromo-2'-deoxyuridine, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining, and Western blot analysis for brain-derived neurotrophic factor, cyclic adenosine monophosphate response element binding protein, and endothelial nitric oxide synthase were conducted. Following adaptation to the animal vivarium and two baseline fluid intake tests, the animals were divided into four groups: the control group, the CMS-induced depression group, the CMS-induced depression and exercise group, and the CMS-induced depression and fluoxetine-treated group. The animals in the CMS groups were exposed to the CMS conditions for 8 weeks and those in the control group were exposed to the control conditions for 8 weeks. After 4 weeks of CMS, the rats in the CMS-induced depression and exercise group were made to run on a motorized treadmill for 30 min once a day for 4 weeks. In the present results, treadmill exercise alleviated CMS-induced depressive symptoms. Treadmill exercise restored sucrose consumption, increased cell proliferation, and decreased apoptotic cell death. The present results suggest the possibility that exercise may improve symptoms of depression. PMID:26730380

  18. NOX2 Inhibition Impairs Early Muscle Gene Expression Induced by a Single Exercise Bout

    PubMed Central

    Henríquez-Olguín, Carlos; Díaz-Vegas, Alexis; Utreras-Mendoza, Yildy; Campos, Cristian; Arias-Calderón, Manuel; Llanos, Paola; Contreras-Ferrat, Ariel; Espinosa, Alejandra; Altamirano, Francisco; Jaimovich, Enrique; Valladares, Denisse M.

    2016-01-01

    Reactive oxygen species (ROS) participate as signaling molecules in response to exercise in skeletal muscle. However, the source of ROS and the molecular mechanisms involved in these phenomena are still not completely understood. The aim of this work was to study the role of skeletal muscle NADPH oxidase isoform 2 (NOX2) in the molecular response to physical exercise in skeletal muscle. BALB/c mice, pre-treated with a NOX2 inhibitor, apocynin, (3 mg/kg) or vehicle for 3 days, were swim-exercised for 60 min. Phospho–p47phox levels were significantly upregulated by exercise in flexor digitorum brevis (FDB). Moreover, exercise significantly increased NOX2 complex assembly (p47phox–gp91phox interaction) demonstrated by both proximity ligation assay and co-immunoprecipitation. Exercise-induced NOX2 activation was completely inhibited by apocynin treatment. As expected, exercise increased the mRNA levels of manganese superoxide dismutase (MnSOD), glutathione peroxidase (GPx), citrate synthase (CS), mitochondrial transcription factor A (tfam) and interleukin-6 (IL-I6) in FDB muscles. Moreover, the apocynin treatment was associated to a reduced activation of p38 MAP kinase, ERK 1/2, and NF-κB signaling pathways after a single bout of exercise. Additionally, the increase in plasma IL-6 elicited by exercise was decreased in apocynin-treated mice compared with the exercised vehicle-group (p < 0.001). These results were corroborated using gp91-dstat in an in vitro exercise model. In conclusion, NOX2 inhibition by both apocynin and gp91dstat, alters the intracellular signaling to exercise and electrical stimuli in skeletal muscle, suggesting that NOX2 plays a critical role in molecular response to an acute exercise. PMID:27471471

  19. NOX2 Inhibition Impairs Early Muscle Gene Expression Induced by a Single Exercise Bout.

    PubMed

    Henríquez-Olguín, Carlos; Díaz-Vegas, Alexis; Utreras-Mendoza, Yildy; Campos, Cristian; Arias-Calderón, Manuel; Llanos, Paola; Contreras-Ferrat, Ariel; Espinosa, Alejandra; Altamirano, Francisco; Jaimovich, Enrique; Valladares, Denisse M

    2016-01-01

    Reactive oxygen species (ROS) participate as signaling molecules in response to exercise in skeletal muscle. However, the source of ROS and the molecular mechanisms involved in these phenomena are still not completely understood. The aim of this work was to study the role of skeletal muscle NADPH oxidase isoform 2 (NOX2) in the molecular response to physical exercise in skeletal muscle. BALB/c mice, pre-treated with a NOX2 inhibitor, apocynin, (3 mg/kg) or vehicle for 3 days, were swim-exercised for 60 min. Phospho-p47(phox) levels were significantly upregulated by exercise in flexor digitorum brevis (FDB). Moreover, exercise significantly increased NOX2 complex assembly (p47(phox)-gp91(phox) interaction) demonstrated by both proximity ligation assay and co-immunoprecipitation. Exercise-induced NOX2 activation was completely inhibited by apocynin treatment. As expected, exercise increased the mRNA levels of manganese superoxide dismutase (MnSOD), glutathione peroxidase (GPx), citrate synthase (CS), mitochondrial transcription factor A (tfam) and interleukin-6 (IL-I6) in FDB muscles. Moreover, the apocynin treatment was associated to a reduced activation of p38 MAP kinase, ERK 1/2, and NF-κB signaling pathways after a single bout of exercise. Additionally, the increase in plasma IL-6 elicited by exercise was decreased in apocynin-treated mice compared with the exercised vehicle-group (p < 0.001). These results were corroborated using gp91-dstat in an in vitro exercise model. In conclusion, NOX2 inhibition by both apocynin and gp91dstat, alters the intracellular signaling to exercise and electrical stimuli in skeletal muscle, suggesting that NOX2 plays a critical role in molecular response to an acute exercise. PMID:27471471

  20. Bi-phase transition diagrams of metallic thin multilayers

    SciTech Connect

    Li, J.C.; Liu, W.; Jiang, Q. . E-mail: jiangq@jlu.edu.cn

    2005-02-01

    Phase transitions of metallic multilayers induced by differences in interface energy are considered thermodynamically, based on a thermodynamic model for interface energy and the Goldschmidt premise for lattice contraction. Bi-phase transition diagrams of Co/Cr, Zr/Nb, Ti/Nb and Ti/Al multilayers are constructed, which are in agreement with experimental results.

  1. Recurrent exercise-induced rhabdomyolysis due to low intensity fitness exercise in a healthy young patient

    PubMed Central

    Karre, Premnath Reddy; Gujral, Jeetinder

    2011-01-01

    Rhabdomyolysis is an uncommon but life threatening condition that develops due to breakdown of muscle and release of intracellular components into the circulation. A 24-year-old man otherwise healthy was admitted to our hospital because of muscle aches and weakness as well as cola coloured urine developed 3 days after carrying out the low intensity exercise. Diagnosis of rhabdomyolysis was made with creatine kinase (CK) levels of 214 356 U/l. He was treated for a similar condition at age 21. A muscle biopsy was done and the findings were normal. Rhabdomyolysis can develop with low intensity exercise; thus, it be considered in healthy young people. Young people with recurrent rhabdomyolysis due to low intensity exercise, in the absence of obvious medical and physical causes, should be evaluated further to rule out uncommon metabolic diseases. Our case demonstrates that complications especially renal failure in patients with rhabdomyolysis do not correspond to CK levels. PMID:22700603

  2. Exercise-induced increase in serum interleukin-6 in humans is related to muscle damage.

    PubMed Central

    Bruunsgaard, H; Galbo, H; Halkjaer-Kristensen, J; Johansen, T L; MacLean, D A; Pedersen, B K

    1997-01-01

    1. This study was performed to test the hypothesis that the exercise-induced increase in circulating cytokine levels is associated with muscle damage. Nine healthy young male subjects performed two high-intensity bicycle exercise trials separated by two weeks. The first trial consisted of 30 min of normal bicycle exercise (concentric exercise), whereas the second consisted of 30 min of braking with reversed revolution (eccentric exercise). The work loads were chosen to give the same increases in heart rate and catecholamine levels in the blood during each trial. 2. Significant increases (P < 0.05) in plasma concentration of creatine kinase (CK), aspartate aminotransferase and alanine aminotransferase were observed only after the eccentric exercise. Furthermore, the level of interleukin-6 (IL-6) in serum increased significantly after the eccentric exercise and was significantly correlated to CK concentration in the following days, whereas no significant changes were found after the concentric exercise. 3. The total concentration of lymphocytes increased significantly (P < 0.05) as a result of eccentric compared with concentric exercise. This was mainly due to a significantly more pronounced recruitment of natural killer (NK) cells and CD8 positive cells (CD8+ cells) during the eccentric trial. However, no significant differences between the two types of work were found in regard to the circulating concentration of monocytes. The concentration of neutrophils was only significantly increased 2 h after the concentric exercise. 4. The finding that high-intensity eccentric exercise caused a more pronounced increase in the plasma level of IL-6, compared with concentric exercise, supports the hypothesis that the post-exercise cytokine production is related to skeletal muscle damage. The fact that no differences between eccentric and concentric exercise were found in the recruitment of most blood mononuclear cell subsets to the blood supports the hypothesis that the

  3. Treadmill exercise induces age and protocol-dependent epigenetic changes in prefrontal cortex of Wistar rats.

    PubMed

    Cechinel, Laura Reck; Basso, Carla Giovana; Bertoldi, Karine; Schallenberger, Bruna; de Meireles, Louisiana Carolina Ferreira; Siqueira, Ionara Rodrigues

    2016-10-15

    Some studies have linked age-related beneficial effects of exercise and epigenetic mechanisms. Although, the impact of treadmill exercise on histone acetylation, histone and DNA methylation marks in aged cortices yet remains poorly understood. Considering the role of frontal cortex on brain functions, we investigated the potential of different exercise protocols, single session and daily exercise, to modulate epigenetic marks, namely global H4 acetylation, histone methyltransferase activity (HMT H3K27) and levels of DNA methytransferase (DNMT1 and DNMT3b) in prefrontal cortices from 3 and 21-months aged Wistar rats. The animals were submitted to two treadmill exercise protocols, single session (20min) or daily moderate (20min/day during 14days). The daily exercise protocol induced an increased in histone H4 acetylation levels in prefrontal cortices of 21-months-old rats, without any effects in young adult group. DNMT3b levels were increased in aged cortices of animals submitted to single session of exercise. These results indicate that prefrontal cortex is susceptible to epigenetic changes in a protocol dependent-manner and that H4 acetylation levels and DNMT3b content changes might be linked at least in part to exercise-induced effects on brain functions. PMID:27418438

  4. Skin testing with food, codeine, and histamine in exercise-induced anaphylaxis.

    PubMed

    Lin, R Y; Barnard, M

    1993-06-01

    A 33-year-old Chinese woman with exercise-induced anaphylaxis after ingesting Chinese seafood noodle soup, was studied for skin test reactivity to food, histamine, and codeine. Prick skin tests were negative for shrimp, wheat, and chicken soup base, but were positive at 5 to 6 mm (wheal diameter) to the whole broth after it had been combined with the other ingredients. No significant (> 3 mm) wheals were observed in eight controls who were simultaneously tested with the broth. To assess the role of exercise, three series of skin tests were performed with histamine, codeine, and whole broth before and after aerobic exercise on two occasions. Codeine elicited consistent increases in wheal size after exercise compared with pre-exercise skin tests. Histamine and whole broth wheal sizes did not increase significantly. Three control subjects also had codeine and histamine skin tests before and after exercise, No exercise-associated increases were noted for codeine. Potential insights into mast cell abnormalities in exercise-induced anaphylaxis may be gained by skin testing patterns with codeine and other mast cell degranulating agents. PMID:8507042

  5. Physical exercise down-regulated locomotor side effects induced by haloperidol treatment in Wistar rats.

    PubMed

    Baptista, Pedro Porto Alegre; de Senna, Priscylla Nunes; Paim, Mariana Fontoura; Saur, Lisiani; Blank, Martina; do Nascimento, Patricia; Ilha, Jocemar; Vianna, Mônica Ryff Moreira; Mestriner, Régis Gemerasca; Achaval, Matilde; Xavier, Léder Leal

    2013-03-01

    Extra-pyramidal symptoms (EPS) such as akinesia, dystonia, gait alteration and tremors are observed when dopamine D2-receptors are blocked by pharmacological agents such as haloperidol. These alterations produce a Parkinson disease-like state (PLS). Physical exercise has been proven to improve gait and locomotor symptoms in Parkinson's disease; we sought to elucidate the effects of physical exercise on PLS induced by chronic administration of haloperidol in rats. We used 48 rats distributed into four groups: Control, Exercise, Haloperidol, and Hal+Exe. All the animals received a daily injection of saline or haloperidol for 30 days, and the exercise groups underwent a daily 30-minute exercise protocol for 20 days. The animals were subjected to the ink-paw test, bar test and open-field test throughout the training period. The haloperidol-induced akinesia increased throughout the days of injections, but exercise was shown to alleviate it. The assessment showed shortened stride length and increased stance width with the use of haloperidol, which were significantly alleviated by exercise. These results indicate that exercise could be an interesting approach towards reducing unwanted EPS caused by haloperidol. PMID:23290938

  6. Exercise-induced interstitial pulmonary edema at sea-level in young and old healthy humans

    PubMed Central

    Taylor, Bryan J.; Carlson, Alex R.; Miller, Andrew D.; Johnson, Bruce D.

    2014-01-01

    We asked whether aged adults are more susceptible to exercise-induced pulmonary edema relative to younger individuals. Lung diffusing capacity for carbon monoxide (DLCO), alveolar-capillary membrane conductance (Dm) and pulmonary-capillary blood volume (Vc) were measured before and after exhaustive discontinuous incremental exercise in 10 young (YNG; 27±3 yr) and 10 old (OLD; 69±5 yr) males. In YNG subjects, Dm increased (11±7%, P=0.031), Vc decreased (−10±9%, P=0.01) and DLCO was unchanged (30.5±4.1 vs. 29.7±2.9 ml/min/mmHg, P=0.44) pre- to post-exercise. In OLD subjects, DLCO and Dm increased (11±14%, P=0.042; 16±14%, P=0.025) but Vc was unchanged (58±23 vs. 56±23 ml, P=0.570) pre- to post-exercise. Group-mean Dm/Vc was greater after vs. before exercise in the YNG and OLD subjects. However, Dm/Vc was lower post-exercise in 2 of the 10 YNG (−7±4%) and 2 of the 10 OLD subjects (−10±5%). These data suggest that exercise decreases interstitial lung fluid in most YNG and OLD subjects, with a small number exhibiting evidence for exercise-induced pulmonary edema. PMID:24200644

  7. Moderate exercise training attenuates aging-induced cardiac inflammation, hypertrophy and fibrosis injuries of rat hearts

    PubMed Central

    Liao, Po-Hsiang; Hsieh, Dennis Jine-Yuan; Kuo, Chia-Hua; Day, Cecilia-Hsuan; Shen, Chia-Yao; Lai, Chao-Hung; Chen, Ray-Jade; Padma, V. Vijaya

    2015-01-01

    Aging is the most important risk factor in cardiovascular disease (CVD), which is the leading causes of death worldwide and the second major cause of death in Taiwan. The major factor in heart failure during aging is heart remodeling, including long-term stress-induced cardiac hypertrophy and fibrosis. Exercise is good for aging heart health, but the impact of exercise training on aging is not defined. This study used 3-, 12- and 18-month-old rats and randomly divided each age group into no exercise training control groups (C3, A12 and A18) and moderate gentle swimming exercise training groups (E3, AE12 and AE18). The protocol of exercise training was swimming five times weekly with gradual increases from the first week from 20 to 60 min for 12 weeks. Analyses of protein from rat heart tissues and sections revealed cardiac inflammation, hypertrophy and fibrosis pathway increases in aged rat groups (A12 and A18), which were improved in exercise training groups (AE12 and AE18). There were no heart injuries in young rat hearts in exercise group E3. These data suggest that moderate swimming exercise training attenuated aging-induced cardiac inflammation, hypertrophy and fibrosis injuries of rat hearts. PMID:26496028

  8. Transient energy deficit induced by exercise increases 24-h fat oxidation in young trained men.

    PubMed

    Iwayama, Kaito; Kawabuchi, Ryosuke; Park, Insung; Kurihara, Reiko; Kobayashi, Masashi; Hibi, Masanobu; Oishi, Sachiko; Yasunaga, Koichi; Ogata, Hitomi; Nabekura, Yoshiharu; Tokuyama, Kumpei

    2015-01-01

    Whole body fat oxidation increases during exercise. However, 24-h fat oxidation on a day with exercise often remains similar to that of sedentary day, when energy intake is increased to achieve an energy-balanced condition. The present study aimed to examine a possibility that time of the day when exercise is performed makes differences in 24-h fat oxidation. As a potential mechanism of exercise affecting 24-h fat oxidation, its relation to exercise-induced transient energy deficit was examined. Nine young male endurance athletes underwent three trials of indirect calorimetry using a metabolic chamber, in which they performed a session of 100 min of exercise before breakfast (AM), after lunch (PM), or two sessions of 50 min of exercise before breakfast and after lunch (AM/PM) at 65% of maximal oxygen uptake. Experimental meals were designed to achieve individual energy balance. Twenty-four-hour energy expenditure was similar among the trials, but 24-h fat oxidation was 1,142 ± 97, 809 ± 88, and 608 ± 46 kcal/24 h in descending order of its magnitude for AM, AM/PM, and PM, respectively (P < 0.05). Twenty-four-hour carbohydrate oxidation was 2,558 ± 110, 2,374 ± 114, and 2,062 ± 96 kcal/24 h for PM, AM/PM, and AM, respectively. In spite of energy-balanced condition over 24 h, exercise induced a transient energy deficit, the magnitude of which was negatively correlated with 24-h fat oxidation (r = -0.72, P < 0.01). Similarly, transient carbohydrate deficit after exercise was negatively correlated with 24-h fat oxidation (r = -0.40, P < 0.05). The time of the day when exercise is performed affects 24-h fat oxidation, and the transient energy/carbohydrate deficit after exercise is implied as a factor affecting 24-h fat oxidation. PMID:25554797

  9. Exercise-induced stimulation of murine macrophage chemotaxis: role of corticosterone and prolactin as mediators.

    PubMed Central

    Ortega, E; Forner, M A; Barriga, C

    1997-01-01

    1. Exercise provokes changes in the immune system, including macrophage activity. Chemotaxis is a necessary function of macrophages if they are to reach the focus of infection and strenuous acute exercise may modulate chemotaxis. However, the precise mechanisms remain unknown. 2. Three experiments were performed in the present study. (1) The effect of strenuous acute exercise (swimming until exhaustion) on the chemotactic capacity of macrophages was evaluated. (2) Peritoneal macrophages from control mice were incubated with plasma from exercised mice or control (no exercise) mice. The differences in the resulting chemotactic capacity were measured. (3) Changes in the concentration of plasma corticosterone and prolactin after exercise were also measured, and the effect of incubation with the post-exercise levels of plasma corticosterone and prolactin on the chemotactic capacity of the peritoneal macrophages was then studied in vitro. 3. Exercise induced an increase in the macrophage chemotaxis index (103 +/- 8 vs. 47 +/- 11 in controls). Incubation with plasma from exercised mice led to an increased level of chemotaxis (68 +/- 18 vs. 40 +/- 6 with plasma from controls). Incubation with concentrations of corticosterone and prolactin similar to those observed in plasma immediately after exercise (corticosterone, 0.72 mumol l-1; prolactin, 88 pmol l-1) raised the chemotactic capacity with respect to that following incubation with the basal concentrations of the hormones in control animals (90 +/- 9 vs. 37 +/- 4 for corticosterone; 72 +/- 9 vs. 41 +/- 4 for prolactin). 4. It is concluded that corticosterone and prolactin may mediate the increased chemotaxis of peritoneal macrophages induced by exercise. Images Figure 3 Figure 4 PMID:9051584

  10. Central release of nitric oxide mediates antinociception induced by aerobic exercise.

    PubMed

    Galdino, G S; Duarte, I D; Perez, A C

    2015-09-01

    Nitric oxide (NO) is a soluble gas that participates in important functions of the central nervous system, such as cognitive function, maintenance of synaptic plasticity for the control of sleep, appetite, body temperature, neurosecretion, and antinociception. Furthermore, during exercise large amounts of NO are released that contribute to maintaining body homeostasis. Besides NO production, physical exercise has been shown to induce antinociception. Thus, the present study aimed to investigate the central involvement of NO in exercise-induced antinociception. In both mechanical and thermal nociceptive tests, central [intrathecal (it) and intracerebroventricular (icv)] pretreatment with inhibitors of the NO/cGMP/KATP pathway (L-NOArg, ODQ, and glybenclamide) prevented the antinociceptive effect induced by aerobic exercise (AE). Furthermore, pretreatment (it, icv) with specific NO synthase inhibitors (L-NIO, aminoguanidine, and L-NPA) also prevented this effect. Supporting the hypothesis of the central involvement of NO in exercise-induced antinociception, nitrite levels in the cerebrospinal fluid increased immediately after AE. Therefore, the present study suggests that, during exercise, the NO released centrally induced antinociception. PMID:25517916

  11. Medium-intensity acute exhaustive exercise induces neural cell apoptosis in the rat hippocampus.

    PubMed

    Li, Shanni; Liu, Jin; Yan, Hengmei

    2013-01-15

    The present study assessed the influence of medium-intensity (treadmill at a speed of 19.3 m/min until exhaustion) and high-intensity (treadmill at a speed of 26.8 m/min until exhaustion) acute exhaustive exercise on rat hippocampal neural cell apoptosis. TUNEL staining showed significantly increased neural cell apoptosis in the hippocampal CA1 region of rats after medium- and high-intensity acute exhaustive exercise, particularly the medium-intensity acute exhaustive exercise, when compared with the control. Immunohistochemistry showed significantly increased expression of the antiapoptotic protein Bcl-2 and the proapoptotic protein Bax in the hippocampal CA1 region of rats after medium- and high-intensity acute exhaustive exercise. Additionally, the ratio of Bax to Bcl-2 increased in both exercise groups. In particular, the medium-intensity acute exhaustive exercise group had significantly higher Bax and Bcl-2 protein expression and a higher Bax/Bcl-2 ratio. These findings indicate that acute exhaustive exercise of different intensities can induce neural cell apoptosis in the hippocampus, and that medium-intensity acute exhaustive exercise results in greater damage when compared with high-intensity exercise. PMID:25206482

  12. Contribution of β-adrenergic receptors to exercise-induced bronchodilatation in healthy humans.

    PubMed

    Antonelli, Andrea; Torchio, Roberto; Bertolaccini, Luca; Terzi, Alberto; Rolfo, Fabrizio; Agostoni, Piergiuseppe; Gulotta, Carlo; Brusasco, Vito; Pellegrino, Riccardo

    2012-10-15

    Exercise in healthy subjects is usually associated with progressive bronchodilatation. Though the decrease in vagal tone is deemed to be the main underlying mechanism, activation of bronchial β(2)-receptors may constitute an additional cause. To examine the contribution of β(2)-adrenergic receptors to bronchodilatation during exercise in healthy humans, we studied 15 healthy male volunteers during maximum exercise test at control conditions and after a non-selective β-adrenergic blocker (carvedilol 12.5mg twice a day until heart rate decreased at least by 10beats/min) and inhaled β(2)-agonist (albuterol 400μg). Airway caliber was estimated from the partial flow at 40% of control forced vital capacity (V˙(part40)) and its changes during exercise from the slope of linear regression analysis of V˙(part40) values against the corresponding minute ventilation during maximal exercise until exhaustion. At control, V˙(part40) increased progressively and significantly with exercise. After albuterol, resting V˙(part40) was significantly larger than at control increased but did not further increase during exercise. After carvedilol, V˙(part40) was similar to control but its increase with exercise was significantly attenuated. These findings suggest that β(2)-adrenergic system plays a major role in exercise-induced bronchodilation in healthy subjects. PMID:22842007

  13. Strenuous exercise induces a hyperreactive rebalanced haemostatic state that is more pronounced in men.

    PubMed

    Huskens, Dana; Roest, Mark; Remijn, Jasper A; Konings, Joke; Kremers, Romy M W; Bloemen, Saartje; Schurgers, Evelien; Selmeczi, Anna; Kelchtermans, Hilde; van Meel, Rinaldo; Meex, Steven J; Kleinegris, Marie-Claire; de Groot, Philip G; Urbanus, Rolf T; Ninivaggi, Marisa; de Laat, Bas

    2016-06-01

    Physical exercise is recommended for a healthy lifestyle. Strenuous exercise, however, may trigger the haemostatic system, increasing the risk of vascular thrombotic events and the incidence of primary cardiac arrest. Our goal was to study the effects of strenuous exercise on risk factors of cardiovascular disease. Blood was collected from 92 healthy volunteers who participated in the amateur version of the pro-tour Amstel Gold cycling race, before and directly after the race. Thrombin generation showed a shortening of the lag time and time to peak and an increase of the velocity index. Interestingly, the endogenous thrombin potential measured in plasma decreased due to reduced prothrombin conversion. Platelet reactivity increased and this effect was stronger in men than in women. Lower fibrinogen and higher D-dimer levels after exercise indicated higher fibrin formation. On the other hand, fibrinolysis was also elevated as indicated by a shortening of the clot lysis time. Exercise activated the endothelium (von Willebrand factor (VWF) and active VWF levels were elevated) and the immune system (concentrations IL-6, IL-8, MCP-1, RANTES and PDGF increased). Additionally, an increased cardiac troponin T level was measured post-exercise. Strenuous exercise induces a temporary hyperreactive state in the body with enhanced pro- and anticoagulant responses. As strenuous exercise has a more pronounced effect on platelet function in male subjects, this gives a possible explanation for the higher incidence of sudden cardiac death during exercise compared to women. This trial is registered at www.clinicaltrials.gov as NCT02048462. PMID:26864794

  14. Hemostatic studies in racing standardbred horses with exercise-induced pulmonary hemorrhage. Hemostatic parameters at rest and after moderate exercise.

    PubMed Central

    Johnstone, I B; Viel, L; Crane, S; Whiting, T

    1991-01-01

    The purpose of this study was to determine whether a defect in hemostasis might be a factor in the etiology of exercise-induced pulmonary hemorrhage (EIPH). Hemostatic parameters were evaluated in 22 EIPH-positive and ten EIPH-negative racing horses while in a rested state. Nineteen EIPH-positive and ten EIPH-negative horses were further evaluated just before and immediately after a 15 min exercise period on a 260 m oval track. When EIPH-positive and EIPH-negative horses were compared at rest, there was no significant difference in any of the coagulation and fibrinolytic parameters studied. There was however, a significant difference in platelet function as assessed by aggregometry. The platelets from affected horses were significantly less responsive than those from nonaffected horses when exposed in vitro to the platelet agonists adenosine diphosphate, collagen and platelet activating factor. Exercise tended to increase the packed cell volume and factor VIII/von Willebrand factor and to decrease platelet aggregation responses to low concentrations of adenosine diphosphate. These effects of exercise however were quantitatively similar in both EIPH-positive and EIPH-negative horses. Reduced platelet function may therefore be a contributing factor in the bleeding characteristic of horses with EIPH. PMID:1909208

  15. Taurine supplementation attenuates delayed increase in exercise-induced arterial stiffness.

    PubMed

    Ra, Song-Gyu; Choi, Youngju; Akazawa, Nobuhiko; Ohmori, Hajime; Maeda, Seiji

    2016-06-01

    There is a delayed increase in arterial stiffness after eccentric exercise that is possibly mediated by the concurrent delayed increase in circulating oxidative stress. Taurine has anti-oxidant action, and taurine supplementation may be able to attenuate the increase in oxidative stress after exercise. The purpose of the present study was to investigate whether taurine supplementation attenuates the delayed increase in arterial stiffness after eccentric exercise. In the present double-blind, randomized, and placebo-controlled trial, we divided 29 young, healthy men into 2 groups. Subjects received either 2.0 g of placebo (n = 14) or taurine (n = 15) 3 times per day for 14 days prior to the exercise, on the day of exercise, and the following 3 days. The exercise consisted of 2 sets of 20 maximal-effort eccentric repetitions with the nondominant arm only. On the morning of exercise and for 4 days thereafter, we measured serum malondialdehyde (MDA) and carotid-femoral pulse wave velocity (cfPWV) as indices of oxidative stress and arterial stiffness, respectively. On the third and fourth days after exercise, both MDA and cfPWV significantly increased in the placebo group. However, these elevations were significantly attenuated in the taurine group. The increase in MDA was associated with an increase in cfPWV from before exercise to 4 days after exercise (r = 0.597, p < 0.05) in the placebo group, but not in the taurine group. Our results suggest that delayed increase in arterial stiffness after eccentric exercise was probably affected by the exercise-induced oxidative stress and was attenuated by the taurine supplementation. PMID:27163699

  16. An Evaluation of Levalbuterol HFA in the Prevention of Exercise-Induced Bronchospasm

    PubMed Central

    Pearlman, D.S.; Rees, William; Schaefer, Kendyl; Huang, Holly; Andrews, William T.

    2007-01-01

    Background Exercise-induced bronchospasm (EIB) affects up to 90% of all patients with asthma. Objective This study evaluated the ability of levalbuterol hydrofluoroalkane (HFA) 90 μg (two actuations of 45 μg) administered via metered dose inhaler (MDI) to protect against EIB in mild-to-moderate asthmatics. Methods This was a randomized, double-blind, placebo-controlled, two-way cross-over study. Patients with asthma (n = 15) were ≥18 years, had a ≥6-month history of EIB, ≥70% baseline predicted forced expiratory volume in 1 second (FEV1), and a 20% to 50% decrease in FEV1 after treadmill exercise challenge using single-blind placebo MDI. Levalbuterol or placebo was self-administered 30 minutes before exercise. Treatment sequences were separated by a 3-to 7-day washout period. Spirometry was performed predose, 20 minutes postdose/pre-exercise, and 5, 10, 15, 30, and 60 minutes post-exercise. The primary endpoint was the maximum percent decrease in FEV1 from baseline (postdose/pre-exercise). The percentage of protected (≤20% decrease in post-exercise FEV1) patients was also assessed. Results Levalbuterol had significantly smaller maximum percent post-exercise decrease in FEV1 compared with placebo (LS mean ± SE; −4.8% ± 2.8% versus −22.5% ± 2.8%, respectively). For levalbuterol, 14/15 (93.3%) patients had <20% decrease in post-exercise FEV1 compared with 8/15 (53.3%) for placebo (p = 0.0143). Treatment was well tolerated. Conclusion Levalbuterol HFA MDI (90 μg) administered 30 minutes before exercise was significantly more effective than placebo in protecting against EIB after a single exercise challenge and was well tolerated. Clinical Implications Levalbuterol HFA MDI when administered before exercise was effective in protecting adults with asthma from EIB. PMID:17994402

  17. Exercise- and Hypoxia-Induced Anaerobic Metabolism and Recovery: A Student Laboratory Exercise Using Teleost Fish

    ERIC Educational Resources Information Center

    Rees, B. B.; Boily, P.; Williamson, L. A. C.

    2009-01-01

    Anaerobic metabolism is recruited in vertebrates under conditions of intense exercise or lowered environmental oxygen availability (hypoxia), typically resulting in the accumulation of lactate in blood and tissues. Lactate will be cleared over time after the reoxygenation of tissues, eventually returning to control levels. Here, we present a…

  18. 1,25-Dihydroxyvitamin D{sub 3} induces biphasic NF-{kappa}B responses during HL-60 leukemia cells differentiation through protein induction and PI3K/Akt-dependent phosphorylation/degradation of I{kappa}B

    SciTech Connect

    Tse, A.K.-W.; Wan, C.-K.; Shen, X.-L.; Zhu, G.-Y.; Cheung, H.-Y.; Yang, M.; Fong, W.-F. . E-mail: wffong@hkbu.edu.hk

    2007-05-01

    1,25-Dihydroxyvitamin D{sub 3} (VD{sub 3}) induces differentiation in a number of leukemia cell lines and under various conditions is able to either stimulate or inhibit nuclear factor kappa B (NF-{kappa}B) activity. Here we report a time-dependent biphasic regulation of NF-{kappa}B in VD{sub 3}-treated HL-60 leukemia cells. After VD{sub 3} treatment there was an early {approx} 4 h suppression and a late 8-72 h prolonged reactivation of NF-{kappa}B. The reactivation of NF-{kappa}B was concomitant with increased IKK activities, IKK-mediated I{kappa}B{alpha} phosphorylation, p65 phosphorylation at residues S276 and S536, p65 nuclear translocation and p65 recruitment to the NF-{kappa}B/vitamin D responsive element promoters. In parallel with NF-{kappa}B stimulation, there was an up-regulation of NF-{kappa}B controlled inflammatory and anti-apoptotic genes such as TNF{alpha}, IL-1{beta} and Bcl-xL. VD{sub 3}-triggered reactivation of NF-{kappa}B was associated with PI3K/Akt phosphorylation. PI3K/Akt antagonists suppressed VD{sub 3}-stimulated I{kappa}B{alpha} phosphorylation as well as NF-{kappa}B-controlled gene expression. The early {approx} 4 h VD{sub 3}-mediated NF-{kappa}B suppression coincided with a prolonged increase of I{kappa}B{alpha} protein which require de novo protein synthesis, lasted for as least 72 h and was insensitive to MAPK, IKK or PI3K/Akt inhibitors. Our data suggest a novel biphasic regulation of NF-{kappa}B in VD{sub 3}-treated leukemia cells and our results may have provided the first molecular explanation for the contradictory observations reported on VD{sub 3}-mediated immune-regulation.

  19. Comparative ability of dobutamine and exercise stress in inducing myocardial ischaemia in active patients.

    PubMed Central

    Marwick, T H; D'Hondt, A M; Mairesse, G H; Baudhuin, T; Wijns, W; Detry, J M; Melin, J A

    1994-01-01

    OBJECTIVE--To compare the ability of dobutamine and exercise stress to induce myocardial ischaemia and perfusion heterogeneity under routine clinical circumstances. DESIGN--86 active patients without previous myocardial infarction were studied by dobutamine and exercise stress protocols and coronary angiography. During both tests patients underwent electrocardiography, digitised echocardiography, and perfusion scintigraphy using Tc-99m methoxybutylisonitrile (MIBI) single photon emission computed tomography. MAIN OUTCOME MEASURE--Coronary disease defined as an ST segment depression of > or = 0.1 mV, a resting or stress induced perfusion defect, or a resting or stress induced wall motion abnormality on exercise and dobutamine stress testing. RESULTS--Dobutamine stress was submaximal in 51 patients because of ingestion of beta adrenoceptor blocking agents on the day of the test (n = 25) or failure to attain the peak dose owing to side effects (n = 28). Exercise was limited in 23 patients by non-cardiac symptoms. The peak heart rate with dobutamine was less than that attained with exercise (105 (25) v 132 (24) beats/min, P < 0.0001); the response to maximal dobutamine stress significantly exceeded that to submaximal stress. Peak blood pressure was greatest with exercise (206 (27) v 173 (25) mm Hg, P < 0.001), values at maximal and submaximal dobutamine stress being comparable. Electrocardiographic evidence of ischaemia was induced less frequently by dobutamine than exercise (32% v 77% of the 56 patients with significant coronary disease, P < 0.01), as was abnormal wall motion (54% v 88%, P < 0.001). Ischaemia was induced more readily with maximal stress of either type; thus the sensitivities of dobutamine and exercise echocardiography were comparable only in patients undergoing a maximal dobutamine testing (73% v 77%, NS). Perfusion heterogeneity was induced in 58% of patients with coronary disease at submaximal dobutamine stress, 73% at maximal dobutamine stress, and

  20. The biphasic interphase-mitotic polarity of cell nuclei induced under DNA replication stress seems to be correlated with Pin2 localization in root meristems of Allium cepa.

    PubMed

    Żabka, Aneta; Trzaskoma, Paweł; Winnicki, Konrad; Polit, Justyna Teresa; Chmielnicka, Agnieszka; Maszewski, Janusz

    2015-02-01

    Long-term treatment of Allium cepa seedlings with low concentration of hydroxyurea (HU) results in a disruption of cell cycle checkpoints, leading root apex meristem (RAM) cells to an abnormal organization of nuclear structures forming interphase (I) and mitotic (M) domains of chromatin at opposite poles of the nucleus. Thus far, both critical cell length and an uneven distribution of cyclin B-like proteins along the nuclear axis have been recognized as essential factors needed to facilitate the formation of biphasic interphase-mitotic (IM) cells. Two new aspects with respect to their emergence are investigated in this study. The first concerns a relationship between the polarity of increasing chromatin condensation (IM orientation) and the acropetal (base→apex) alignment of RAM cell files. The second problem involves the effects of auxin (IAA), on the frequency of IM cells. We provide evidence that there is an association between the advanced M-poles of the IM cell nuclei and the polarized accumulation sites of auxin efflux carriers (PIN2 proteins) and IAA. Furthermore, our observations reveal exclusion regions for PIN2 proteins in the microtubule-rich structures, such as preprophase bands (PPBs) and phragmoplast. The current and previous studies have prompted us to formulate a hypothetical mechanism linking PIN2-mediated unilateral localization of IAA and the induction of bipolar IM cells in HU-treated RAMs of A. cepa. PMID:25462968

  1. Prophylactic acetylsalicylic acid attenuates the inflammatory response but fails to protect exercise-induced liver damage in exercised rats.

    PubMed

    Huang, Kuo-Chin; Chiu, Yi-Han; Liao, Kuang-Wen; Ke, Chun-Yen; Lee, Chung-Jen; Chao, Yann-Fen C; Lee, Ru-Ping

    2016-09-01

    This study evaluated the effects of acetylsalicylic acid (ASA) on exercise-induced inflammatory response, muscle damage, and liver injury in rats. Wistar-Kyoto (WKY) rats were divided into six groups: control (C), exercise (E), C+20mg ASA, E+20mg ASA, C+100mg/kg ASA, and E+100mg ASA groups. ASA or a vehicle was orally administered through gavage 1h before a treadmill test. Upon trial completion, blood was drawn at 1, 12, and 24h for biochemical analysis, and livers were excised at 24h for a histological assessment. Our results revealed that 100mg/kg ASA significantly reduced interleukin (IL)-6 and tumor necrosis factor (TNF)-α levels in the E groups; however, the IL-10 level was considerably increased. Moreover, aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels and histological hepatic damage increased significantly in the E+100mg ASA group compared with the corresponding changes in the E group. These results suggest that the prophylactic administration of particularly high-dose ASA alleviates exercise-induced inflammatory response but exacerbates liver injury. PMID:27262381

  2. The response of the pulmonary circulation and right ventricle to exercise: exercise-induced right ventricular dysfunction and structural remodeling in endurance athletes (2013 Grover Conference series).

    PubMed

    La Gerche, André; Roberts, Timothy; Claessen, Guido

    2014-09-01

    There is unequivocal evidence that exercise results in considerable health benefits. These are the result of positive hormonal, metabolic, neuronal, and structural changes brought about by the intermittent physiological challenge of exercise. However, there is evolving evidence that intense exercise may place disproportionate physiological stress on the right ventricle (RV) and the pulmonary circulation. Both echocardiographic and invasive studies are consistent in demonstrating that pulmonary arterial pressures increase progressively with exercise intensity, such that the harder one exercises, the greater the load on the RV. This disproportionate load can result in fatigue or damage of the RV if the intensity and duration of exercise is sufficiently prolonged. This is distinctly different from the load imposed by exercise on the left ventricle (LV), which is moderated by a greater capacity for reductions in systemic afterload. Finally, given the increasing RV demand during exercise, it may be hypothesized that chronic exercise-induced cardiac remodeling (the so-called athlete's heart) may also disproportionately affect the RV. Indeed, there is evidence, although somewhat inconsistent, that RV volume increases may be relatively greater than those for the LV. Perhaps more importantly, there is a suggestion that chronic endurance exercise may cause electrical remodeling, predisposing some athletes to serious arrhythmias originating from the RV. Thus, a relatively consistent picture is emerging of acute stress, prolonged fatigue, and long-term remodeling, which all disproportionately affect the RV. Thus, we contend that the RV should be considered a potential Achilles' heel of the exercising heart. PMID:25621154

  3. Endothelin-1 in exhaled breath condensate of allergic asthma patients with exercise-induced bronchoconstriction

    PubMed Central

    Zietkowski, Ziemowit; Skiepko, Roman; Tomasiak, Maria M; Bodzenta-Lukaszyk, Anna

    2007-01-01

    Background Exercise-induced bronchoconstriction (EIB) is a highly prevalent condition, whose pathophysiology is not well understood. Endothelins are proinflammatory, profibrotic, broncho- and vasoconstrictive peptides which play an important role in the development of airway inflammation and remodeling in asthma. The aim of the study was to evaluate the changes in endothelin-1 levels in exhaled breath condensate following intensive exercise in asthmatic patients. Methods The study was conducted in a group of 19 asthmatic patients (11 with EIB, 8 without EIB) and 7 healthy volunteers. Changes induced by intensive exercise in the concentrations of endothelin-1 (ET-1) in exhaled breath condensate (EBC) during 24 hours after an exercise challenge test were determined. Moreover, the possible correlations of these measurements with the results of other tests commonly associated with asthma and with the changes of airway inflammation after exercise were observed. Results In asthmatic patients with EIB a statistically significant increase in the concentration of ET-1 in EBC collected between 10 minutes and 6 hours after an exercise test was observed. The concentration of ET-1 had returned to its initial level 24 hours after exercise. No effects of the exercise test on changes in the concentrations of ET-1 in EBC in either asthmatic patients without EIB or healthy volunteers were observed. A statistically significant correlation between the maximum increase in ET-1 concentrations in EBC after exercise and either baseline FENO and the increase in FENO or BHR to histamine 24 hours after exercise in the groups of asthmatics with EIB was revealed. Conclusion The release of ET-1 from bronchial epithelium through the influence of many inflammatory cells essential in asthma and interactions with other cytokines, may play an important role in increase of airway inflammation which was observed after postexercise bronchoconstriction in asthmatic patients. PMID:17973986

  4. Preventive Effects of Antioxidants and Exercise on Muscle Atrophy Induced by Ischemic Reperfusion

    PubMed Central

    Umei, Namiko; Ono, Takeya; Oki, Sadaaki; Otsuka, Akira; Otao, Hiroshi; Tsumiyama, Wakako; Tasaka, Atsushi; Ishikura, Hideki; Aihara, Kazuki; Sato, Yuta; Shimizu, Michele Eisemann

    2014-01-01

    [Purpose] This study aimed to determine whether muscle atrophy induced by ischemic reperfusion injury in rats can be prevented by the administration of antioxidants and exercise. [Subjects] Rats were randomly divided into five groups: non-treated, ischemic, exercise, ascorbic acid and exercise, and tocopherol and exercise. [Methods] The relative weight ratio of the soleus muscle and the length of the soleus muscle fiber cross-section minor axis were used for the evaluation of muscle atrophy. Pain was assessed as the weight-bearing ratio of the ischemic side. A multiple comparison test and the paired t-test were used for the statistical analyses. [Results] Compared with the non-treated group, the relative weight ratios of the soleus muscle and the lengths of the soleus muscle fiber cross-section minor axis significantly decreased in the other groups. Excluding the non-treated group, the relative weight ratios of the soleus muscle were heaviest in the tocopherol and exercise group. Excluding the non-treated group, the lengths of the soleus muscle fiber cross-section minor axis were longest in the tocopherol and exercise group, followed by the ischemic, exercise, and ascorbic acid and exercise groups. The amount of antioxidant substances did not decrease on the weight-bearing ratio of the ischemic side. [Conclusion] In this study, using an experimental rat model, we confirmed that antioxidants and exercise effect muscle atrophy induced by ischemic reperfusion. The results show that muscle regeneration was facilitated by phagocytosis in the tocopherol and exercise group. PMID:25540491

  5. Moderate Exercise Attenuates Lipopolysaccharide-Induced Inflammation and Associated Maternal and Fetal Morbidities in Pregnant Rats

    PubMed Central

    Macdonald-Goodfellow, Shannyn K.; Surita, Fernanda G.; Pinto e Silva, João L.; Tayade, Chandrakant; Othman, Maha; Ozolinš, Terence R. S.

    2016-01-01

    Fetal growth restriction (FGR) and coagulopathies are often associated with aberrant maternal inflammation. Moderate-intensity exercise during pregnancy has been shown to increase utero-placental blood flow and to enhance fetal nutrition as well as fetal and placental growth. Furthermore, exercise is known to reduce inflammation. To evaluate the effect of moderate-intensity exercise on inflammation associated with the development of maternal coagulopathies and FGR, Wistar rats were subjected to an exercise regime before and during pregnancy. To model inflammation-induced FGR, pregnant rats were administered daily intraperitoneal injections of E. coli lipopolysaccharide (LPS) on gestational days (GD) 13.5–16.5 and sacrificed at GD 17.5. Control rats were injected with saline. Maternal hemostasis was assessed by thromboelastography. Moderate-intensity exercise prevented LPS-mediated increases in white blood cell counts measured on GD 17.5 and improved maternal hemostasis profiles. Importantly, our data reveal that exercise prevented LPS-induced FGR. Moderate-intensity exercise initiated before and maintained during pregnancy may decrease the severity of maternal and perinatal complications associated with abnormal maternal inflammation. PMID:27124733

  6. Combination of exercise training and erythropoietin prevents cancer-induced muscle alterations

    PubMed Central

    Pin, Fabrizio; Busquets, Silvia; Toledo, Miriam; Camperi, Andrea; Lopez-Soriano, Francisco J.; Costelli, Paola; Argilés, Josep M.; Penna, Fabio

    2015-01-01

    Cancer cachexia is a syndrome characterized by loss of skeletal muscle mass, inflammation, anorexia and anemia, contributing to patient fatigue and reduced quality of life. In addition to nutritional approaches, exercise training (EX) has been proposed as a suitable tool to manage cachexia. In the present work the effect of mild exercise training, coupled to erythropoietin (EPO) administration to prevent anemia, has been tested in tumor-bearing mice. In the C26 hosts, acute exercise does not prevent and even worsens muscle wasting. Such pattern is prevented by EPO co-administration or by the adoption of a chronic exercise protocol. EX and EPO co-treatment spares oxidative myofibers from atrophy and counteracts the oxidative to glycolytic shift, inducing PGC-1α. LLC hosts are responsive to exercise and their treatment with the EX-EPO combination prevents the loss of muscle strength and the onset of mitochondrial ultrastructural alterations, while increases muscle oxidative capacity and intracellular ATP content, likely depending on PGC-1α induction and mitophagy promotion. Consistently, muscle-specific PGC-1α overexpression prevents LLC-induced muscle atrophy and Atrogin-1 hyperexpression. Overall, the present data suggest that low intensisty exercise can be an effective tool to be included in combined therapeutic approaches against cancer cachexia, provided that anemia is coincidently treated in order to enhance the beneficial action of exercise. PMID:26636649

  7. Exercise prevents β-aminopropionitrile-induced morphological changes to type I collagen in murine bone

    PubMed Central

    Hammond, Max A; Wallace, Joseph M

    2015-01-01

    This study evaluated the effects of reduced enzymatic crosslinking, exercise and the ability of exercise to prevent the deleterious impact of reduced crosslinking on collagen D-spacing. Eight-week-old female mice were divided into four weight-matched groups receiving daily injections of either phosphate-buffered saline (PBS) or 300 mg kg−1 β-aminopropionitrile (BAPN) while undergoing normal cage activity (Sed) or 30 min per day of treadmill exercise (Ex) for 21 consecutive days. BAPN caused a downward shift in the D-spacing distribution in Sed BAPN compared with Sed PBS (P<0.001) but not in Ex BAPN (P=0.429), indicating that exercise can prevent changes in collagen morphology caused by BAPN. Exercise had no effect on D-spacing in PBS control mice (P=0.726), which suggests that exercise-induced increases in lysyl oxidase may be a possible mechanism for preventing BAPN-induced changes in D-spacing. The D-spacing changes were accompanied by an increase in mineral crystallinity/maturity due to the main effect of BAPN (P=0.016). However, no changes in nanoindentation, reference point indentation or other Raman spectroscopy parameters were observed. The ability of exercise to rescue BAPN-driven changes in collagen morphology necessitates further research into the use of mechanical stimulation as a preventative therapy for collagen-based diseases. PMID:25798234

  8. Exercise-induced skeletal muscle signaling pathways and human athletic performance.

    PubMed

    Camera, Donny M; Smiles, William J; Hawley, John A

    2016-09-01

    Skeletal muscle is a highly malleable tissue capable of altering its phenotype in response to external stimuli including exercise. This response is determined by the mode, (endurance- versus resistance-based), volume, intensity and frequency of exercise performed with the magnitude of this response-adaptation the basis for enhanced physical work capacity. However, training-induced adaptations in skeletal muscle are variable and unpredictable between individuals. With the recent application of molecular techniques to exercise biology, there has been a greater understanding of the multiplicity and complexity of cellular networks involved in exercise responses. This review summarizes the molecular and cellular events mediating adaptation processes in skeletal muscle in response to exercise. We discuss established and novel cell signaling proteins mediating key physiological responses associated with enhanced exercise performance and the capacity for reactive oxygen and nitrogen species to modulate training adaptation responses. We also examine the molecular bases underpinning heterogeneous responses to resistance and endurance exercise and the dissociation between molecular 'markers' of training adaptation and subsequent exercise performance. PMID:26876650

  9. MRI-detectable changes in mouse brain structure induced by voluntary exercise.

    PubMed

    Cahill, Lindsay S; Steadman, Patrick E; Jones, Carly E; Laliberté, Christine L; Dazai, Jun; Lerch, Jason P; Stefanovic, Bojana; Sled, John G

    2015-06-01

    Physical exercise, besides improving cognitive and mental health, is known to cause structural changes in the brain. Understanding the structural changes that occur with exercise as well as the neuroanatomical correlates of a predisposition for exercise is important for understanding human health. This study used high-resolution 3D MR imaging, in combination with deformation-based morphometry, to investigate the macroscopic changes in brain structure that occur in healthy adult mice following four weeks of voluntary exercise. We found that exercise induced changes in multiple brain structures that are involved in motor function and learning and memory including the hippocampus, dentate gyrus, stratum granulosum of the dentate gyrus, cingulate cortex, olivary complex, inferior cerebellar peduncle and regions of the cerebellum. In addition, a number of brain structures, including the hippocampus, striatum and pons, when measured on MRI prior to the start of exercise were highly predictive of subsequent exercise activity. Exercise tended to normalize these pre-existing differences between mice. PMID:25800209

  10. Neurobiological Alterations Induced by Exercise and Their Impact on Depressive Disorders

    PubMed Central

    Helmich, Ingo; Latini, Alexandra; Sigwalt, Andre; Carta, Mauro Giovanni; Machado, Sergio; Velasques, Bruna; Ribeiro, Pedro; Budde, Henning

    2010-01-01

    Background: The impact of physical activity on brain metabolic functions has been investigated in different studies and there is growing evidence that exercise can be used as a preventive and rehabilitative intervention in the treatment of depressive disorders. However, the exact neuronal mechanisms underlying the latter phenomenon have not been clearly elucidated. The present article summarises key results derived from studies that focussed on the neurobiological impact of exercise on brain metabolic functions associated with depressive disorders. Since major depressive disorder (MDD) is a life threatening disease it is of great significance to find reliable strategies to prevent or to cure this illness. Therefore, the aim of this paper is to review (1) the physiological relationship between physical activity and depressive disorders and (2) the potential neurobiological alterations induced by exercise that might lead to the relief of mental disorders like depression. Methods: We searched electronic databases for literature concerning the relationship between exercise and depression from 1963 until 2009. Results: The data suggests an association between physical inactivity and higher levels of depressive symptoms. Properly designed studies could show that exercise training can be as effective as antidepressive medications. Conclusion: The exact mechanisms how exercise affects the brain are not fully understood and the literature lacks of well designed studies concerning the effects of exercise training on depressive disorders. But the observed antidepressant actions of exercise are strong enough that it already can be used as an alternative to current medications in the treatment of depressive disorders. PMID:21283646

  11. High protein diet maintains glucose production during exercise-induced energy deficit: a controlled trial

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inadequate energy intake induces changes in endogenous glucose production (GP) to preserve muscle mass. Whether addition provision of dietary protein modulates GP response to energy deficit is unclear. The objective was to determine whether exercise-induced energy deficit effects on glucose metaboli...

  12. Optimal use of fluids of varying formulations to minimise exercise-induced disturbances in homeostasis.

    PubMed

    Lamb, D R; Brodowicz, G R

    1986-01-01

    The rationale underlying the development of various formulations of beverages for consumption before, during, and/or after physical exercise is that such formulations should minimise some of the disturbances in physiological homeostasis that occur during exercise and thereby prevent injury and/or enhance performance. Exercise- and dehydration-induced increases in core temperature, body fluid osmolality, heart rate, losses of plasma and other body fluid volumes, and carbohydrate depletion are probably the most important homeostatic disturbances that can be ameliorated by fluid consumption. With the exception of athletes subject to hyponatraemia after consumption of ordinary water during prolonged activity, changes in electrolyte concentrations in the body fluids of most athletes do not justify the inclusion of electrolytes in fluid replacement beverages to be consumed during exercise. However, small amounts of sodium added to water does speed gastric emptying and fluid absorption from the intestine. Recent evidence suggests that a precompetition meal high in easily digested carbohydrates should be consumed not later than 5 to 6 hours before competition. There is little published research on the optimal composition of this meal. Water ingestion 30 to 60 minutes before exercise seems to be of benefit to temperature regulation and cardiovascular homeostasis if the exercise is of moderate intensity (50 to 65% VO2max), but probably has little effect at the higher intensities of athletic performance. There is no systematic evidence to support the inclusion of calcium or sodium chloride in drinks consumed an hour or 2 before exercise. Furthermore, if glucose solutions are fed 15 to 45 minutes before prolonged exercise, they will probably cause a fall in blood glucose during exercise and may adversely affect performance. These adverse effects are not present when fructose is consumed before exercise. Contrary to the adverse effects of glucose feedings 15 to 60 minutes

  13. Myoglobin A79G polymorphism association with exercise-induced skeletal muscle damage.

    PubMed

    Cui, T; Jiang, M S

    2016-01-01

    We assessed the role of A79G, a polymorphism of the myoglobin gene (MB), in susceptibility to exercise-induced skeletal muscle damage. Between January 2012 and December 2014, a total of 166 cases with exercise-induced skeletal muscle damage and 166 controls were recruited into our study. Genotyping of MB A79G was carried out using polymerase chain reaction coupled with restriction fragment length polymorphism. Using unconditional logistic regression analysis, we found that the GG genotype of MB A79G was associated with higher risk of exercise-induced muscle damage compared with the wild-type genotype, and the OR (95%CI) was 2.91 (1.20-7.59). Compared with the AA genotype, the AG+GG genotype was associated with a significantly increased risk of exercise-induced muscle damage for those with blood lactic acid ≥1.80 mM (OR = 2.05; 95%CI = 1.09-3.88). In conclusion, we found that the A79G polymorphism of the MB gene plays an important role in influencing the development of exercise-induced skeletal muscle damage. PMID:27323063

  14. Hemodynamic effects of high intensity interval training in COPD patients exhibiting exercise-induced dynamic hyperinflation.

    PubMed

    Nasis, I; Kortianou, E; Vasilopoulou, Μ; Spetsioti, S; Louvaris, Z; Kaltsakas, G; Davos, C H; Zakynthinos, S; Koulouris, N G; Vogiatzis, I

    2015-10-01

    Dynamic hyperinflation (DH) has a significant adverse effect on cardiovascular function during exercise in COPD patients. COPD patients with (n = 25) and without (n = 11) exercise-induced DH undertook an incremental (IET) and a constant-load exercise test (CLET) sustained at 75% peak work (WRpeak) prior to and following an interval cycling exercise training regime (set at 100% WRpeak with 30-s work/30-s rest intervals) lasting for 12 weeks. Cardiac output (Q) was assessed by cardio-bio-impedance (PhysioFlow, enduro, PF-O7) to determine Q mean response time (QMRT) at onset (QMRT(ON)) and offset (QMRT(OFF)) of CLET. Post-rehabilitation only those patients exhibiting exercise-induced DH demonstrated significant reductions in QMRT(ON) (from 82.2 ± 4.3 to 61.7 ± 4.2 s) and QMRT(OFF) (from 80.5 ± 3.8 to 57.2 ± 4.9 s ). These post-rehabilitation adaptations were associated with improvements in inspiratory capacity, thereby suggesting that mitigation of the degree of exercise-induced DH improves central hemodynamic responses in COPD patients. PMID:26112284

  15. Exercise-induced asthma: critical analysis of the protective role of montelukast

    PubMed Central

    Carver, Terrence W

    2009-01-01

    Exercise-induced asthma/exercise-induced bronchospasm (EIA/EIB) is a prevalent and clinically important disease affecting young children through older adulthood. These terms are often used interchangeably and the differences are not clearly defined in the literature. The pathogenesis of EIA/EIB may be different in those with persistent asthma compared to those with exercise-induced symptoms only. The natural history of EIA is unclear and may be different for elite athletes. Leukotriene biology has helped the understanding of EIB. The type and intensity of exercise are important factors for EIB. Exercise participation is necessary for proper development and control of EIA is recommended. Symptoms of EIB should be confirmed by proper testing. Biologic markers may also be helpful in diagnosis. Not all exercise symptoms are from EIB. Many medication and nonpharmacologic treatments are available. Asthma education is an important component of managing EIA. Many medications have been tested and the comparisons are complicated. Montelukast is a US Food and Drug Administration-approved asthma and EIB controller and has a number of potential advantages to other asthma medications including short onset of action, ease of use, and lack of tolerance. Not all patients improve with montelukast and rescue medication should be available. PMID:21437147

  16. Exercise training reverses aging-induced impairment of myogenic constriction in skeletal muscle arterioles

    PubMed Central

    Ghosh, Payal; Mora Solis, Fredy R.; Dominguez, James M.; Spier, Scott A.; Donato, Anthony J.; Delp, Michael D.

    2015-01-01

    To investigate whether exercise training can reverse age-related impairment of myogenic vasoconstriction in skeletal muscle arterioles, young (4 mo) and old (22 mo) male Fischer 344 rats were randomly assigned to either sedentary or exercise-trained groups. The roles of the endothelium and Kv1 channels in age- and exercise training-induced adaptations of myogenic responses were assessed through evaluation of pressure-induced constriction in endothelium-intact and denuded soleus muscle arterioles in the presence and absence of the Kv1 channel blocker, correolide. Exercise training enhanced myogenic constriction in arterioles from both old and young rats. In arterioles from old rats, exercise training restored myogenic constriction to a level similar to that of arterioles from young sedentary rats. Removal of the endothelium did not alter myogenic constriction of arterioles from young sedentary rats, but reduced myogenic constriction in arterioles from young exercise-trained rats. In contrast, endothelial removal had no effect on myogenic constriction of arterioles from old exercise-trained rats, but increased myogenic vasoconstriction in old sedentary rats. The effect of Kv1 channel blockade was also dependent on age and training status. In arterioles from young sedentary rats, Kv1 blockade had little effect on myogenic constriction, whereas in old sedentary rats Kv1 blockade increased myogenic constriction. After exercise training, Kv1 channel blockade increased myogenic constriction in arterioles from both young and old rats. Thus exercise training restores myogenic constriction of arterioles from old rats and enhances myogenic constriction from young rats through adaptations of the endothelium and smooth muscle Kv1 channels. PMID:25634999

  17. Effect of dry warm air on respiratory water loss in children with exercise-induced asthma.

    PubMed

    Tabka, Z; Ben Jebria, A; Vergeret, J; Guenard, H

    1988-07-01

    The variation in respiratory water loss (RWL) over time, expressed as the mass of water vapor lost per liter (body temperature and pressure, saturated) of ventilation (MH2O), was investigated in two groups: (1) children with exercise-induced asthma; and (2) healthy children. Children were matched for age and sex and went without medication for at least 12 hours before each experiment. The children breathed dry warm air (TI = 28.4 degrees C +/- 0.3 degree C) for 15 minutes while bicycling at constant and moderate work load (50 W). The MH2O was measured by collecting and weighing the expired water vapor (1) at rest breathing in warm conditions of inspired gas (control values), (2) every five minutes during exercise while breathing dry warm air, and (3) four minutes after the end of exercise. Pulmonary function tests were performed before and six minutes after exercise. The results were abnormal only in children with exercise-induced asthma. During exercise, RWL significantly fell (compared to control value) at the tenth and 15th minute in both groups. Whereas normal subjects recovered their initial values for MH2O four minutes after stopping exercise, asthmatic children still had a reduction in respiratory water loss. During exercise, MH2O decreased a little more in healthy than in asthmatic children. The decrease in MH2O in both groups suggests that the means to fully humidify expired gas are overwhelmed by thermal stress. The lack of increase in MH2O in asthmatic children on stopping exercise suggests that the airway mucosa is unable to produce enough water vapor and is thus dehydrated and probably hyperosmotic. PMID:3383660

  18. Resistance exercise-induced fluid shifts: change in active muscle size and plasma volume

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, L. L.; Convertino, V. A.; Dudley, G. A.

    1995-01-01

    The purpose of this study was to test the hypothesis that the reduction in plasma volume (PV) induced by resistance exercise reflects fluid loss to the extravascular space and subsequently selective increase in cross-sectional area (CSA) of active but not inactive skeletal muscle. We compared changes in active and inactive muscle CSA and PV after barbell squat exercise. Magnetic resonance imaging (MRI) was used to quantify muscle involvement in exercise and to determine CSA of muscle groups or individual muscles [vasti (VS), adductor (Add), hamstring (Ham), and rectus femoris (RF)]. Muscle involvement in exercise was determined using exercise-induced contrast shift in spin-spin relaxation time (T2)-weighted MR images immediately postexercise. Alterations in muscle size were based on the mean CSA of individual slices. Hematocrit, hemoglobin, and Evans blue dye were used to estimate changes in PV. Muscle CSA and PV data were obtained preexercise and immediately postexercise and 15 and 45 min thereafter. A hierarchy of muscle involvement in exercise was found such that VS > Add > Ham > RF, with the Ham and RF showing essentially no involvement. CSA of the VS and Add muscle groups were increased 10 and 5%, respectively, immediately after exercise in each thigh with no changes in Ham and RF CSA. PV was decreased 22% immediately following exercise. The absolute loss of PV was correlated (r2 = 0.75) with absolute increase in muscle CSA immediately postexercise, supporting the notion that increased muscle size after resistance exercise reflects primarily fluid movement from the vascular space into active but not inactive muscle.

  19. Effect of age on exercise-induced alterations in cognitive executive function: relationship to cerebral perfusion.

    PubMed

    Lucas, Samuel J E; Ainslie, Philip N; Murrell, Carissa J; Thomas, Kate N; Franz, Elizabeth A; Cotter, James D

    2012-08-01

    Regular exercise improves the age-related decline in cerebral blood flow (CBF) and is associated with improved cognitive function; however, less is known about the direct relationship between CBF and cognitive function. We examined the influence of healthy aging on the capability of acute exercise to improve cognition, and whether exercise-induced improvements in cognition are related to CBF and cortical hemodynamics. Middle cerebral artery blood flow velocity (MCAv; Doppler) and cortical hemodynamics (NIRS) were measured in 13 young (24±5 y) and 9 older (62±3 y) participants at rest and during cycling at 30% and 70% of heart rate range (HRR). Cognitive performance was assessed using a computer-adapted Stroop task (i.e., test of executive function cognition) at rest and during exercise. Average response times on the Stroop task were slower for the older compared to younger group for both simple and difficult tasks (P<0.01). Independent of age, difficult-task response times improved during exercise (P<0.01), with the improvement greater at 70% HRR exercise (P=0.04 vs. 30% HRR). Higher MCAv was correlated with faster response times for simple and difficult tasks at rest (R(2)=0.47 and R(2)=0.47, respectively), but this relation uncoupled progressively during exercise. Exercise-induced increases in MCAv were similar and unaltered during cognitive tasks for both age groups. In contrast, prefrontal cortical hemodynamic NIRS measures [oxyhemoglobin (O(2)Hb) and total hemoglobin (tHb)] were differentially affected by exercise intensity, age and cognitive task; e.g., there were smaller increases in [O(2)Hb] and [tHb] in the older group between exercise intensities (P<0.05). These data indicate that: 1) Regardless of age, cognitive (executive) function is improved while exercising; 2) while MCAv is strongly related to cognition at rest, this relation becomes uncoupled during exercise, and 3) there is dissociation between global CBF and regional cortical oxygenation and

  20. The response of the pulmonary circulation and right ventricle to exercise: exercise-induced right ventricular dysfunction and structural remodeling in endurance athletes (2013 Grover Conference series)

    PubMed Central

    Roberts, Timothy; Claessen, Guido

    2014-01-01

    Abstract There is unequivocal evidence that exercise results in considerable health benefits. These are the result of positive hormonal, metabolic, neuronal, and structural changes brought about by the intermittent physiological challenge of exercise. However, there is evolving evidence that intense exercise may place disproportionate physiological stress on the right ventricle (RV) and the pulmonary circulation. Both echocardiographic and invasive studies are consistent in demonstrating that pulmonary arterial pressures increase progressively with exercise intensity, such that the harder one exercises, the greater the load on the RV. This disproportionate load can result in fatigue or damage of the RV if the intensity and duration of exercise is sufficiently prolonged. This is distinctly different from the load imposed by exercise on the left ventricle (LV), which is moderated by a greater capacity for reductions in systemic afterload. Finally, given the increasing RV demand during exercise, it may be hypothesized that chronic exercise–induced cardiac remodeling (the so-called athlete’s heart) may also disproportionately affect the RV. Indeed, there is evidence, although somewhat inconsistent, that RV volume increases may be relatively greater than those for the LV. Perhaps more importantly, there is a suggestion that chronic endurance exercise may cause electrical remodeling, predisposing some athletes to serious arrhythmias originating from the RV. Thus, a relatively consistent picture is emerging of acute stress, prolonged fatigue, and long-term remodeling, which all disproportionately affect the RV. Thus, we contend that the RV should be considered a potential Achilles’ heel of the exercising heart. PMID:25621154

  1. Voluntary exercise-induced changes in beta2-adrenoceptor signalling in rat ventricular myocytes.

    PubMed

    Stones, Rachel; Natali, Antonio; Billeter, Rudolf; Harrison, Simon; White, Ed

    2008-09-01

    Regular exercise is beneficial to cardiovascular health. We tested whether mild voluntary exercise training modifies key myocardial parameters [ventricular mass, intracellular calcium ([Ca2+]i) handling and the response to beta-adrenoceptor (beta-AR) stimulation] in a manner distinct from that reported for beneficial, intensive training and pathological hypertrophic stimuli. Female rats performed voluntary wheel-running exercise for 6-7 weeks. The mRNA expression of target proteins was measured in left ventricular tissue using real-time reverse transcriptase-polymerase chain reaction. Simultaneous measurement of cell shortening and [Ca2+]i transients were made in single left ventricular myocytes and the inotropic response to beta1- and beta2-AR stimulation was measured. Voluntary exercise training resulted in cardiac hypertrophy, the heart weight to body weight ratio being significantly greater in trained compared with sedentary animals. However, voluntary exercise caused no significant alteration in the size or time course of myocyte shortening and [Ca2+]i transients or in the mRNA levels of key proteins that regulate Ca2+ handling. The positive inotropic response to beta1-AR stimulation and the level of beta1-AR mRNA were unaltered by voluntary exercise but both mRNA levels and inotropic response to beta2-AR stimulation were significantly reduced in trained animals. The beta2-AR inotropic response was restored by exposure to pertussis toxin. We propose that in contrast to pathological stimuli and to beneficial, intense exercise training, modulation of Ca2+ handling is not a major adaptive mechanism in the response to mild voluntary exercise. In addition, and in a reversal of the situation seen in heart failure, voluntary exercise training maintains the beta1-AR response but reduces the beta2-AR response. Therefore, although voluntary exercise induces cardiac hypertrophy, there are distinct differences between its effects on key myocardial regulatory mechanisms

  2. Exercise induces cortical plasticity after neonatal spinal cord injury in the rat.

    PubMed

    Kao, Tina; Shumsky, Jed S; Murray, Marion; Moxon, Karen A

    2009-06-10

    Exercise-induced cortical plasticity is associated with improved functional outcome after brain or nerve injury. Exercise also improves functional outcomes after spinal cord injury, but its effects on cortical plasticity are not known. The goal of this investigation was to study the effect of moderate exercise (treadmill locomotion, 3 min/d, 5 d/week) on the somatotopic organization of forelimb and hindlimb somatosensory cortex (SI) after neonatal thoracic transection. We used adult rats spinalized as neonates because some of these animals develop weight-supported stepping, and, therefore, the relationship between cortical plasticity and stepping could also be examined. Acute, single-neuron mapping was used to determine the percentage of cortical cells responding to cutaneous forelimb stimulation in normal, spinalized, and exercised spinalized rats. Multiple single-neuron recording from arrays of chronically implanted microwires examined the magnitude of response of these cells in normal and exercised spinalized rats. Our results show that exercise not only increased the percentage of responding cells in the hindlimb SI but also increased the magnitude of the response of these cells. This increase in response magnitude was correlated with behavioral outcome measures. In the forelimb SI, neonatal transection reduced the percentage of responding cells to forelimb stimulation, but exercise reversed this loss. This restoration in the percentage of responding cells after exercise was accompanied by an increase in their response magnitude. Therefore, the increase in responsiveness of hindlimb SI to forelimb stimulation after neonatal transection and exercise may be due, in part, to the effect of exercise on the forelimb SI. PMID:19515923

  3. Exercise Training Prevents TNF-α Induced Loss of Force in the Diaphragm of Mice

    PubMed Central

    Mangner, Norman; Linke, Axel; Oberbach, Andreas; Kullnick, Yvonne; Gielen, Stephan; Sandri, Marcus; Hoellriegel, Robert; Matsumoto, Yasuharu; Schuler, Gerhard; Adams, Volker

    2013-01-01

    Rationale Inflammatory cytokines like tumor necrosis factor alpha (TNF-α) are elevated in congestive heart failure and are known to induce the production of reactive oxygen species as well as to deteriorate respiratory muscle function. Objectives Given the antioxidative effects of exercise training, the aim of the present study was to investigate if exercise training is capable of preventing a TNF-α induced loss of diaphragmatic force in mice and, if so, to elucidate the potential underlying mechanisms. Methods Prior to intraperitoneal injection of TNF-α or saline, C57Bl6 mice were assigned to four weeks of exercise training or sedentary behavior. Diaphragmatic force and power generation were determined in vitro. Expression/activity of radical scavenger enzymes, enzymes producing reactive oxygen species and marker of oxidative stress were measured in the diaphragm. Main Results In sedentary animals, TNF-α reduced specific force development by 42% concomitant with a 2.6-fold increase in the amount of carbonylated α-actin and creatine kinase. Furthermore, TNF-α led to an increased NAD(P)H oxidase activity in both sedentary and exercised mice whereas xanthine oxidase activity and intramitochondrial ROS production was only enhanced in sedentary animals by TNF-α. Exercise training prevented the TNF-α induced force reduction and led to an enhanced mRNA expression and activity of glutathione peroxidase. Carbonylation of proteins, in particular of α-actin and creatine kinase, was diminished by exercise training. Conclusion TNF-α reduces the force development in the diaphragm of mice. This effect is almost abolished by exercise training. This may be a result of reduced carbonylation of proteins due to the antioxidative properties of exercise training. PMID:23300968

  4. The influence of fatigue-induced increase in relative work rate on temperature regulation during exercise.

    PubMed

    Kacin, Alan; Golja, Petra; Tipton, Michael J; Eiken, Ola; Mekjavic, Igor B

    2008-05-01

    Heat-loss responses during steady-load exercise are affected by an increase in relative work rate induced by muscle ischaemia or hypoxaemia. The present study investigated whether progressive increases in perception of exertion and relative oxygen uptake %VO2peak which occur during prolonged steady-load exercise as a result of progressively increased peripheral fatigue, might also affect the regulation of heat loss responses and hence the exercise-induced increase in mean body temperature. Ten male subjects first performed a ramp-test to exhaustion on a cycle ergometer to evaluate their initial peak oxygen uptake (Control VO2peak). On a separate day, 120 min of cycling at constant power output corresponding to 60% of Control VO2peak was performed in thermoneutral environment (Ta = 23 degrees C, RH = 50%, wind speed = 5 m s(-1)). This was immediately followed by another maximal performance test (Fatigue VO2peak). During prolonged exercise, median (range) rating of perceived exertion for whole-body (RPEwb) increased (P < 0.01) from initial 3.5 (1-5) to 5.5 (5-9) at the end of exercise. Fatigue VO2peak and peak power output were 9 (5) and 10 (5)% lower (P < 0.01) when compared to control values. At the onset of exercise, heat production, mechanical efficiency, heat loss and mean body temperature increased towards asymptotic values, thereafter remained constant throughout the 120 min exercise, despite the concomitant progressive increase in relative work rate, as reflected in increased RPEwb and relative oxygen uptake. It is thus concluded that the increase in relative work rate induced predominantly by peripheral muscle fatigue affects neither the level of increase in mean body temperature nor the regulation of heat loss responses during prolonged steady-load exercise. PMID:18202847

  5. Mechanisms Involved in Exercise-Induced Cardioprotection: A Systematic Review

    PubMed Central

    Borges, Juliana Pereira; Lessa, Marcos Adriano

    2015-01-01

    Background Acute myocardial infarction is the leading cause of morbidity and mortality worldwide. Furthermore, research has shown that exercise, in addition to reducing cardiovascular risk factors, can also protect the heart against injury due to ischemia and reperfusion through a direct effect on the myocardium. However, the specific mechanism involved in exerciseinduced cardiac preconditioning is still under debate. Objective To perform a systematic review of the studies that have addressed the mechanisms by which aerobic exercise promotes direct cardioprotection against ischemia and reperfusion injury. Methods A search was conducted using MEDLINE, Literatura Latino-Americana e do Caribe de Informação em Ciências da Saúde, and Scientific Electronic Library Online databases. Data were extracted in a standardized manner by two independent researchers, who were responsible for assessing the methodological quality of the studies. Results The search retrieved 78 studies; after evaluating the abstracts, 30 studies were excluded. The manuscripts of the remaining 48 studies were completely read and, of these, 20 were excluded. Finally, 28 studies were included in this systematic review. Conclusion On the basis of the selected studies, the following are potentially involved in the cardioprotective response to exercise: increased heat shock protein production, nitric oxide pathway involvement, increased cardiac antioxidant capacity, improvement in ATP-dependent potassium channel function, and opioid system activation. Despite all the previous investigations, further research is still necessary to obtain more consistent conclusions. PMID:25830711

  6. An open-label study examining the effect of pharmacological treatment on mannitol- and exercise-induced airway hyperresponsiveness in asthmatic children and adolescents with exercise-induced bronchoconstriction

    PubMed Central

    2014-01-01

    Background Mannitol- and exercise bronchial provocation tests are both used to diagnose exercise-induced bronchoconstriction. The study aim was to compare the short-term treatment response to budesonide and montelukast on airway hyperresponsiveness to mannitol challenge test and to exercise challenge test in children and adolescents with exercise-induced bronchoconstriction. Methods Patients were recruited from a paediatric asthma rehabilitation clinic located in the Swiss Alps. Individuals with exercise-induced bronchoconstriction and a positive result in the exercise challenge test underwent mannitol challenge test on day 0. All subjects then received a treatment with 400 μg budesonide and bronchodilators as needed for 7 days, after which exercise- and mannitol-challenge tests were repeated (day 7). Montelukast was then added to the previous treatment and both tests were repeated again after 7 days (day 14). Results Of 26 children and adolescents with exercise-induced bronchoconstriction, 14 had a positive exercise challenge test at baseline and were included in the intervention study. Seven of 14 (50%) also had a positive mannitol challenge test. There was a strong correlation between airway responsiveness to exercise and to mannitol at baseline (r = 0.560, p = 0.037). Treatment with budesonide and montelukast decreased airway hyperresponsiveness to exercise challenge test and to a lesser degree to mannitol challenge test. The fall in forced expiratory volume in one second during exercise challenge test was 21.7% on day 0 compared to 6.7% on day 14 (p = 0.001) and the mannitol challenge test dose response ratio was 0.036%/mg on day 0 compared to 0.013%/mg on day 14 (p = 0.067). Conclusion Short-term treatment with an inhaled corticosteroid and an additional leukotriene receptor antagonist in children and adolescents with exercise-induced bronchoconstriction decreases airway hyperresponsiveness to exercise and to mannitol. PMID:25084607

  7. Thermoreversible (Ionic-Liquid-Based) Aqueous Biphasic Systems

    PubMed Central

    Passos, Helena; Luís, Andreia; Coutinho, João A. P.; Freire, Mara G.

    2016-01-01

    The ability to induce reversible phase transitions between homogeneous solutions and biphasic liquid-liquid systems, at pre-defined and suitable operating temperatures, is of crucial relevance in the design of separation processes. Ionic-liquid-based aqueous biphasic systems (IL-based ABS) have demonstrated superior performance as alternative extraction platforms, and their thermoreversible behaviour is here disclosed by the use of protic ILs. The applicability of the temperature-induced phase switching is further demonstrated with the complete extraction of two value-added proteins, achieved in a single-step. It is shown that these temperature-induced mono(bi)phasic systems are significantly more versatile than classical liquid-liquid systems which are constrained by their critical temperatures. IL-based ABS allow to work in a wide range of temperatures and compositions which can be tailored to fit the requirements of a given separation process. PMID:26843320

  8. Thermoreversible (Ionic-Liquid-Based) Aqueous Biphasic Systems

    NASA Astrophysics Data System (ADS)

    Passos, Helena; Luís, Andreia; Coutinho, João A. P.; Freire, Mara G.

    2016-02-01

    The ability to induce reversible phase transitions between homogeneous solutions and biphasic liquid-liquid systems, at pre-defined and suitable operating temperatures, is of crucial relevance in the design of separation processes. Ionic-liquid-based aqueous biphasic systems (IL-based ABS) have demonstrated superior performance as alternative extraction platforms, and their thermoreversible behaviour is here disclosed by the use of protic ILs. The applicability of the temperature-induced phase switching is further demonstrated with the complete extraction of two value-added proteins, achieved in a single-step. It is shown that these temperature-induced mono(bi)phasic systems are significantly more versatile than classical liquid-liquid systems which are constrained by their critical temperatures. IL-based ABS allow to work in a wide range of temperatures and compositions which can be tailored to fit the requirements of a given separation process.

  9. Respiratory heat/water loss alone does not determine the severity of exercise-induced asthma.

    PubMed

    Noviski, N; Bar-Yishay, E; Gur, I; Godfrey, S

    1988-03-01

    Respiratory heat loss (RHL) or water loss (RWL) have been proposed as possible triggering factors in exercise and hyperventilation-induced asthma (EIA and HIA). It has recently been demonstrated that exercise intensity and climatic factors are both important in determining the severity of EIA. Eight young asthmatics performed both exercise and isocapnic hyperventilation (IHV) manoeuvres under identical climatic conditions, as part of our investigation of these interactive factors which determine the severity of the asthmatic response. It was found that, when challenged at low ventilatory levels, exercise produced a significantly attenuated asthmatic response compared to IHV. The fall in forced expired volume in 1 sec (delta FEV1) following exercise was 15 +/- 4% as compared with 27 +/- 3% after IHV (p less than 0.002). It is concluded that while the hypernoea in exercise may serve as a trigger, exercise per se introduces an additional factor which serves to limit the full response seen with IHV. This attenuated response is revealed at low ventilatory levels but is masked at high levels. PMID:3384078

  10. The Effects of Voluntary Exercise on Oocyte Quality in a Diet-Induced Obese Murine Model

    PubMed Central

    Boudoures, Anna L.; Chi, Maggie; Thompson, Alysha; Zhang, Wendy; Moley, Kelle H.

    2016-01-01

    Obesity negatively affects many aspects of the human body, including reproductive function. In females, the root of the decline in fertility is linked to problems in the oocyte. Problems seen in oocytes that positively correlate with increasing BMI include changes to the metabolism, lipid accumulation, meiosis, and metaphase II (MII) spindle structure. Studies in mice indicate dietary interventions fail to reverse these problems [4]. How exercise affects the oocytes has not been addressed. Therefore, we hypothesized an exercise intervention would improve oocyte quality. Here we show in a mouse model of an exercise intervention can improve lipid metabolism in germinal vesicle (GV) stage oocytes. Oocytes significantly increased activity and transcription of the β-oxidation enzyme Hadha (Hydroxyacyl-CoA-dehydrogenase) in response to exercise training only if the mice had been fed a high fat diet (HFD). An exercise intervention also reversed the lipid accumulation seen in GV stage oocytes of HFD females. However, delays in meiosis and disorganized MII spindles remained present. Therefore, exercise is able to improve, but not reverse, damage imparted on oocytes as a result of a high fat diet and obesity. By utilizing an exercise intervention on a HFD, we determined only lipid content and lipid metabolism is changed in GV oocytes. Moving forward, interventions to improve oocyte quality may need to be more targeted to the oocyte specifically. Because of the HFD induced deficiency in β-oxidation, dietary supplementation with substrates to improve lipid utilization may be more beneficial. PMID:26700938

  11. Prefrontal lactate predicts exercise-induced cognitive dysfunction in Gulf War Illness

    PubMed Central

    Rayhan, Rakib U; Raksit, Megna P; Timbol, Christian R; Adewuyi, Oluwatoyin; VanMeter, John W; Baraniuk, James N

    2013-01-01

    Background: 25% to 30% of Veterans deployed to the 1990 to 1991 Persian Gulf War exhibit an idiopathic syndrome of chronic fatigue, exertional exhaustion, pain, hyperalgesia, cognitive and affective dysfunction known as Gulf War Illness (GWI). Methods: Gulf War veterans (n=15) and sedentary veteran and civilian controls (n=11) completed a 2-back working memory test in an fMRI before and after two bicycle exercise stress test. We performed single voxel 1H MRS to evaluate brain metabolic differences in the left anterior cingulate cortex and the changes associated with exercise. Results: Eight GWI subjects increased their 2-back scores after exercise (labelled increasers) and seven GWI subjects decreased their 2-back scores after exercise (labelled decreasers). These phenotypic responses were absent for controls. Decreasers had significantly elevated prefrontal lactate levels compared to Increasers prior to completion of the exercise stress tests. Evaluation of prefrontal lactate levels prior to exercise demonstrated predictability (ROC analysis) of the two diametrically opposed subgroups. Conclusion: Prefrontal lactate levels may be a potential biomarker for exercise-induced subgroups in GWI. The alterations in brain energetics may be in part responsible for a subgroup of GWI and underlie some of the symptoms present in the patient population. PMID:23573365

  12. PGC-1α is Dispensable for Exercise-Induced Mitochondrial Biogenesis in Skeletal Muscle

    PubMed Central

    Rowe, Glenn C.; El-Khoury, Riyad; Patten, Ian S.; Rustin, Pierre; Arany, Zolt

    2012-01-01

    Exercise confers numerous health benefits, many of which are thought to stem from exercise-induced mitochondrial biogenesis (EIMB) in skeletal muscle. The transcriptional coactivator PGC-1α, a potent regulator of metabolism in numerous tissues, is widely believed to be required for EIMB. We show here that this is not the case. Mice engineered to lack PGC-1α specifically in skeletal muscle (Myo-PGC-1αKO mice) retained intact EIMB. The exercise capacity of these mice was comparable to littermate controls. Induction of metabolic genes after 2 weeks of in-cage voluntary wheel running was intact. Electron microscopy revealed no gross abnormalities in mitochondria, and the mitochondrial biogenic response to endurance exercise was as robust in Myo-PGC-1αKO mice as in wildtype mice. The induction of enzymatic activity of the electron transport chain by exercise was likewise unperturbed in Myo-PGC-1αKO mice. These data demonstrate that PGC-1α is dispensable for exercise-induced mitochondrial biogenesis in skeletal muscle, in sharp contrast to the prevalent assumption in the field. PMID:22848618

  13. Mechanisms of exercise-induced improvements in the contractile apparatus of the mammalian myocardium.

    PubMed

    Kemi, O J; Wisløff, U

    2010-08-01

    One of the main outcomes of aerobic endurance exercise training is the improved maximal oxygen uptake, and this is pivotal to the improved work capacity that follows the exercise training. Improved maximal oxygen uptake in turn is at least partly achieved because exercise training increases the ability of the myocardium to produce a greater cardiac output. In healthy subjects, this has been demonstrated repeatedly over many decades. It has recently emerged that this scenario may also be true under conditions of an initial myocardial dysfunction. For instance, myocardial improvements may still be observed after exercise training in post-myocardial infarction heart failure. In both health and disease, it is the changes that occur in the individual cardiomyocytes with respect to their ability to contract that by and large drive the exercise training-induced adaptation to the heart. Here, we review the evidence and the mechanisms by which exercise training induces beneficial changes in the mammalian myocardium, as obtained by means of experimental and clinical studies, and argue that these changes ultimately alter the function of the whole heart and contribute to the changes in whole-body function. PMID:20353489

  14. Elevated central venous pressure: a consequence of exercise training-induced hypervolemia?

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.; Mack, G. W.; Nadel, E. R.

    1991-01-01

    Resting blood volumes and arterial and central venous pressures (CVP) were measured in 14 men before and after exercise training to determine whether training-induced hypervolemia is accompanied by a change in total vascular capacitance. In addition, resting levels of plasma arginine vasopressin (AVP), atrial natriuretic peptide (ANP), aldosterone (Ald), and norepinephrine (NE) were measured. The same measurements were conducted in seven subjects who did not undergo exercise and acted as controls. Exercise training consisted of 10 wk of controlled cycle exercise for 30 min/day, 4 days/wk at 75-80% of maximal O2 uptake (VO2max). A training effect was verified by a 20% increase in VO2max, a resting bradycardia, and a 9% increase in blood volume. Mean arterial blood pressure was unaltered by exercise training, but resting CVP increased by 16% (P less than 0.05). The percent change in blood volume from before to after training was linearly related to the percent change in CVP (r = 0.903, P less than 0.05). As a consequence of elevations in both blood volume and CVP, the volume-to-pressure ratio was unchanged after exercise training. Plasma AVP, ANP, Ald, and NE were unaltered. Our results indicate that elevated CVP is a consequence of training-induced hypervolemia without alteration in total effective venous capacitance.

  15. Exercise-induced heart mitochondrial cholesterol depletion influences the inhibition of mitochondrial swelling.

    PubMed

    Ziolkowski, Wieslaw; Vadhana M S, Dhivya; Kaczor, Jan Jacek; Olek, Robert Antoni; Flis, Damian Jozef; Halon, Malgorzata; Wozniak, Michal; Fedeli, Donatella; Carloni, Manuel; Antosiewicz, Jedrzej; Gabbianelli, Rosita

    2013-10-01

    The significance of the reduction of the cholesterol pool in heart mitochondria after exercise is still unknown. Recently, published data have suggested that cholesterol may influence the components of mitochondrial contact site and affect mitochondrial swelling. Therefore, the aim of this study was to determine whether the decreased cholesterol content in heart mitochondria caused by prolonged swimming may provoke changes in their bioenergetics and result in an increased resistance to calcium chloride-induced mitochondrial swelling. Male Wistar rats were divided into a sedentary control group and an exercise group. The rats exercised for 3 h, burdened with an additional 3% of their body weight. Their hearts were removed immediately after completing the exercise. The left ventricle was divided and used for experiments. Mitochondrial cholesterol content, membrane fluidity and mitochondrial bioenergetics were measured in the control and exercised rat heart mitochondria. To assess whether mitochondrial modifications are linked to disruption of lipid microdomains, methyl-β-cyclodextrin, a well-known lipid microdomain-disrupting agent and cholesterol chelator, was applied to the mitochondria of the control group. Cholesterol depletion, increased membrane fluidity and increased resistance to calcium chloride-induced swelling were observed in postexercise heart crude mitochondrial fraction. Similar results were achieved in control mitochondria treated with 2% methyl-β-cyclodextrin. All of the mitochondrial bioenergetics parameters were similar between the groups. Therefore, the disruption of raft-like microdomains appears to be an adaptive change in the rat heart following exercise. PMID:23733522

  16. Elevated central venous pressure: A consequence of exercise training-induced hypervolemia

    NASA Technical Reports Server (NTRS)

    Convertino, Victor A.; Mack, Gary W.; Nadel, Ethan R.

    1990-01-01

    Resting plasma volumes, and arterial and central venous pressures (CVP) were measured in 16 men before and after exercise training to determine if training-induced hypervolemia could be explained by a change in total vascular capacitance. In addition, resting levels of plasma vasopressin (AVP), atrial natriuretic peptide (ANP), aldosterone (ALD), and norepinephrine (NE) were measured before and after training. The same measurements of vacular volume, pressures, and plasma hormones were measured in 8 subjects who did not undergo exercise and acted as controls. The exercise training program consisted of 10 weeks of controlled cycle exercise for 30 min/d, 4 d/wk at 75 to 80 percent of maximal oxygen uptake (VO2max). A training effect was verified by a 20 percent increase in VO2max, a resting bradycardia, and a 370 ml (9 percent) increase in blood volume. Mean arterial blood pressure was unaltered by exercise training, but resting CVP increased. The percent change in blood volume from before to after training was linearly related to the percent change in CVP. As a consequence of elevations in both blood volume and CVP, the volume-to-pressure ratio was essentially unchanged following exercise training. Plasma AVP, ANP, ALD, and NE were unaltered. Results indicate that elevated CVP is a consequence of training-induced hypervolemia without alteration in total effective venous capacitance. This may represent a resetting of the pressure-volume stimulus-response relation for regulation of blood volume.

  17. Two cases of food-dependent exercise-induced anaphylaxis with different culprit foods

    PubMed Central

    Mobayed, Hassan M.S.; Ali Al-Nesf, Maryam

    2014-01-01

    Food-dependent exercise-induced anaphylaxis (FDEIA) is one of the severe allergic reactions in which symptoms develop only if exercise takes place within a few hours of eating a specific food. It is important to consider FDEIA in cases of unexplained anaphylaxis as reactions can occur several hours after ingesting the culprit food(s). We herein report the first two cases of FDEIA in the Middle East. The first one is induced by wheat, while the other by peanut. The pathophysiology, predisposing factors, diagnosis, and treatment of FDEIA are also summarized here. PMID:24551018

  18. Can Exercise Ameliorate Aromatase Inhibitor-Induced Cognitive Decline in Breast Cancer Patients?

    PubMed

    Li, Cuicui; Zhou, Chenglin; Li, Rena

    2016-08-01

    Aromatase inhibitors (AIs) have been commonly used as an effective adjuvant therapy in treatment of breast cancer, especially for menopausal women with estrogen receptor-positive breast cancer. Due to the nature of aromatase, the key enzyme for endogenous estrogen synthesis, inhibitory of aromatase-induced side effects, such as cognitive impairment has been reported in both human and animal studies. While extensive evidence suggested that physical exercises can improve learning and memory activity and even prevent age-related cognitive decline, basic research revealed some common pathways between exercise and estrogen signaling that affected cognitive function. This review draws on clinical and basic studies to assess the potential impact of exercise in cognitive function from women treated with AIs for breast cancer and explore the potential mechanism and effects of exercise on estrogen-related cognition. PMID:26223800

  19. Effects of nicardipine on cardiac volume at rest and during exercise-induced angina

    PubMed Central

    Silke, B.; Verma, S. P.; Frais, M. A.; Hafizullah, M.; Taylor, S. H.

    1985-01-01

    1 The action of nicardipine on cardiac volume, both at rest and during exercise-induced angina, was evaluated in 12 patients with angiographically-proven coronary artery disease. 2 Nicardipine given to patients at rest reduced systemic vascular resistance and mean arterial pressure and increased heart rate and cardiac index. The left ventricular filling pressure, ejection fraction (EF), end-diastolic and end-systolic volumes were unchanged. 3 During supine bicycle exercise, the reduction in systemic arterial blood pressure following nicardipine increased cardiac and stroke index and attenuated the rise in left ventricular filling pressure observed in the control exercise. 4 The effects of nicardipine on EF, end-diastolic and end-systolic cardiac volumes were dependent on the baseline cardiac reserve. In patients with EF < 50%, nicardipine improved EF and left ventricular exercise volumes. PMID:2862901

  20. The L-Z complexity of exercise-induced muscle fatigue based on acoustic myographye

    NASA Astrophysics Data System (ADS)

    Yijian, Min; Xinyuan, Liu; Tingting, Wang

    2014-01-01

    The mechanism of exercise fatigue was investigated during exercise using L-Z complexity of non-linear analysis. Muscle fatigue was induced in the sitting position by lifting the heel under a load. An acoustic myogram of the gastrocnemius was obtained until exhaustion. The different modes of the speed responses were calculated using the L-Z complexity method, which analyzes muscle fibers participation, while the exercise is in progress. The L-Z complexity decreased incrementally with decreases in muscle strength, reaching a minimum value when the muscle was exhausted. Our data indicate that the L-Z complexity method is easy to use and effective at revealing the dynamic characteristics and variations of exercise fatigue. This method could be used to monitor sports training.

  1. Exhaustive submaximal endurance and resistance exercises induce temporary immunosuppression via physical and oxidative stress

    PubMed Central

    Jin, Chan-Ho; Paik, Il-Young; Kwak, Yi-Sub; Jee, Yong-Seok; Kim, Joo-Young

    2015-01-01

    Regular running and strength training are the best ways to improve aerobic capacity and develop the size of skeletal muscles. However, uncontrolled physical activities can often lead to an undertraining or over-training syndrome. In particular, overtraining causes persistent fatigue and reduces physical performance due to changes in the various physiological and immunological factors. In this study, we gave an exhaustive submaximal endurance or resistance exercise to participants and investigated the relationship between physical stress (cortisol level in blood), oxidative stress (intracellular ROS accumulation), and adaptive immune response (CD4:CD8 ratio). Materials and Methods Ten male volunteers were recruited, and performed a submaximal endurance or resistance exercise with 85% of VO2max or 1-repetition maximum until exhaustion. Blood samples were collected at rest, and at 0 and 30 min after the exercise. Cortisol levels, oxidative stress, and immune cell phenotypes in peripheral blood were evaluated. Cortisol levels in the sera increased after the exhaustive endurance and resistance exercises and such increments were maintained through the recovery. Intra-cellular ROS levels also increased after the exhaustive endurance and resistance exercises. The ratio of CD4+ T cells to CD8+ T cells after each type of submaximal exercise decreased compared with that at the resting stage, and returned to the resting level at 30 min after the exercise. In this study, an exhaustive endurance or a resistance exercise with submaximal intensity caused excessive physical stress, intra-cellular oxidative stress, and post-exercise immunosuppression. This result suggests that excessive physical stress induced temporary immune dysfunction via physical and oxidative stress. PMID:26331134

  2. Ammonium Chloride Ingestion Attenuates Exercise-Induced mRNA Levels in Human Muscle

    PubMed Central

    Mündel, Toby; Pilegaard, Henriette; Hawke, Emma; Leikis, Murray; Lopez-Villalobos, Nicolas; Oliveira, Rodrigo S. F.; Bishop, David J.

    2015-01-01

    Minimizing the decrease in intracellular pH during high-intensity exercise training promotes greater improvements in mitochondrial respiration. This raises the intriguing hypothesis that pH may affect the exercise-induced transcription of genes that regulate mitochondrial biogenesis. Eight males performed 10x2-min cycle intervals at 80% V˙O2peak intensity on two occasions separated by ~2 weeks. Participants ingested either ammonium chloride (ACID) or calcium carbonate (PLA) the day before and on the day of the exercise trial in a randomized, counterbalanced order, using a crossover design. Biopsies were taken from the vastus lateralis muscle before and after exercise. The mRNA level of peroxisome proliferator-activated receptor co-activator 1α (PGC-1α), citrate synthase, cytochome c and FOXO1 was elevated at rest following ACID (P<0.05). During the PLA condition, the mRNA content of mitochondrial- and glucose-regulating proteins was elevated immediately following exercise (P<0.05). In the early phase (0–2 h) of post-exercise recovery during ACID, PGC-1α, citrate synthase, cytochome C, FOXO1, GLUT4, and HKII mRNA levels were not different from resting levels (P>0.05); the difference in PGC-1α mRNA content 2 h post-exercise between ACID and PLA was not significant (P = 0.08). Thus, metabolic acidosis abolished the early post-exercise increase of PGC-1α mRNA and the mRNA of downstream mitochondrial and glucose-regulating proteins. These findings indicate that metabolic acidosis may affect mitochondrial biogenesis, with divergent responses in resting and post-exercise skeletal muscle. PMID:26656911

  3. Structural and functional prevention of hypoxia-induced pulmonary hypertension by individualized exercise training in mice.

    PubMed

    Weissmann, Norbert; Peters, Dorothea M; Klöpping, Christina; Krüger, Karsten; Pilat, Christian; Katta, Susmitha; Seimetz, Michael; Ghofrani, Hossein A; Schermuly, Ralph T; Witzenrath, Martin; Seeger, Werner; Grimminger, Friedrich; Mooren, Frank C

    2014-06-01

    Pulmonary hypertension (PH) is a disease with a poor prognosis characterized by a vascular remodeling process and an increase in pulmonary vascular resistance. While a variety of reports demonstrated that exercise training exerts beneficial effects on exercise performance and quality of life in PH patients, it is not known how physical exercise affects vascular remodeling processes occurring in hypoxia-induced PH. Therefore, we investigated the effect of individualized exercise training on the development of hypoxia-induced PH in mice. Training effects were compared with pharmacological treatment with the phosphodiesterase 5 inhibitor Sildenafil or a combination of training plus Sildenafil. Trained mice who received Sildenafil showed a significantly improved walking distance (from 88.9 ± 8.1 to 146.4 ± 13.1 m) and maximum oxygen consumption (from 93.3 ± 2.9 to 105.5 ± 2.2% in combination with Sildenafil, to 102.2 ± 3.0% with placebo) compared with sedentary controls. Right ventricular systolic pressure, measured by telemetry, was at the level of healthy normoxic animals, whereas right heart hypertrophy did not benefit from training. Most interestingly, the increase in small pulmonary vessel muscularization was prevented by training. Respective counterregulatory processes were detected for the nitric oxide-soluble guanylate cyclase-phosphodiesterase system. We conclude that individualized daily exercise can prevent vascular remodeling in hypoxia-induced PH. PMID:24705723

  4. [Exercise-induced asthma in children and oral terbutaline. A dose-response relationship study].

    PubMed

    Hertz, B; Fuglsang, G; Holm, E B

    1994-09-26

    We wanted to assess the protective effects on exercise-induced asthma as well as the clinical efficacy and safety of increasing doses of a new sustained-release formulation of terbutaline sulphate in 17 asthmatic children aged 6-12 years (mean 9 years). Placebo, 2, 4, and 6 mg terbutaline were given b.i.d. for 14 days in a randomized, double-blind, cross-over design. At the end of each two week period, an exercise test was performed and plasma terbutaline was measured. Compared with placebo, no significant effect was seen on asthma symptoms monitored at home, or on exercise-induced asthma. The percentage falls in FEV1 after the exercise test were 36, 35, 27 and 28%, after placebo, 4, 8 and 12 mg terbutaline/day, respectively. A small but statistically significant dose-related increase was seen in morning and evening peak expiratory flow (PEF) recordings. It is concluded that continuous treatment, even with high doses or oral terbutaline, does not offer clinically useful protection against exercise-induced asthma. PMID:7985255

  5. Ultra-endurance exercise induces stress and inflammation and affects circulating hematopoietic progenitor cell function.

    PubMed

    Stelzer, I; Kröpfl, J M; Fuchs, R; Pekovits, K; Mangge, H; Raggam, R B; Gruber, H-J; Prüller, F; Hofmann, P; Truschnig-Wilders, M; Obermayer-Pietsch, B; Haushofer, A C; Kessler, H H; Mächler, P

    2015-10-01

    Although amateur sports have become increasingly competitive within recent decades, there are as yet few studies on the possible health risks for athletes. This study aims to determine the impact of ultra-endurance exercise-induced stress on the number and function of circulating hematopoietic progenitor cells (CPCs) and hematological, inflammatory, clinical, metabolic, and stress parameters in moderately trained amateur athletes. Following ultra-endurance exercise, there were significant increases in leukocytes, platelets, interleukin-6, fibrinogen, tissue enzymes, blood lactate, serum cortisol, and matrix metalloproteinase-9. Ultra-endurance exercise did not influence the number of CPCs but resulted in a highly significant decline of CPC functionality after the competition. Furthermore, Epstein-Barr virus was seen to be reactivated in one of seven athletes. The link between exercise-induced stress and decline of CPC functionality is supported by a negative correlation between cortisol and CPC function. We conclude that ultra-endurance exercise induces metabolic stress and an inflammatory response that affects not only mature hematopoietic cells but also the function of the immature hematopoietic stem and progenitor cell fraction, which make up the immune system and provide for regeneration. PMID:25438993

  6. The endocannabinoid system mediates aerobic exercise-induced antinociception in rats.

    PubMed

    Galdino, Giovane; Romero, Thiago R L; Silva, José Felipe P; Aguiar, Daniele C; de Paula, Ana Maria; Cruz, Jader S; Parrella, Cosimo; Piscitelli, Fabiana; Duarte, Igor D; Di Marzo, Vincenzo; Perez, Andrea C

    2014-02-01

    Exercise-induced antinociception is widely described in the literature, but the mechanisms involved in this phenomenon are poorly understood. Systemic (s.c.) and central (i.t., i.c.v.) pretreatment with CB₁ and CB₂ cannabinoid receptor antagonists (AM251 and AM630) blocked the antinociception induced by an aerobic exercise (AE) protocol in both mechanical and thermal nociceptive tests. Western blot analysis revealed an increase and activation of CB₁ receptors in the rat brain, and immunofluorescence analysis demonstrated an increase of activation and expression of CB₁ receptors in neurons of the periaqueductal gray matter (PAG) after exercise. Additionally, pretreatment (s.c., i.t. and i.c.v.) with endocannabinoid metabolizing enzyme inhibitors (MAFP and JZL184) and an anandamide reuptake inhibitor (VDM11) prolonged and intensified this antinociceptive effect. These results indicate that exercise could activate the endocannabinoid system, producing antinociception. Supporting this hypothesis, liquid-chromatography/mass-spectrometry measurements demonstrated that plasma levels of endocannabinoids (anandamide and 2-arachidonoylglycerol) and of anandamide-related mediators (palmitoylethanolamide and oleoylethanolamide) were increased after AE. Therefore, these results suggest that the endocannabinoid system mediates aerobic exercise-induced antinociception at peripheral and central levels. PMID:24148812

  7. Exercise-induced norepinephrine decreases circulating hematopoietic stem and progenitor cell colony-forming capacity.

    PubMed

    Kröpfl, Julia M; Stelzer, Ingeborg; Mangge, Harald; Pekovits, Karin; Fuchs, Robert; Allard, Nathalie; Schinagl, Lukas; Hofmann, Peter; Dohr, Gottfried; Wallner-Liebmann, Sandra; Domej, Wolfgang; Müller, Wolfram

    2014-01-01

    A recent study showed that ergometry increased circulating hematopoietic stem and progenitor cell (CPC) numbers, but reduced hematopoietic colony forming capacity/functionality under normoxia and normobaric hypoxia. Herein we investigated whether an exercise-induced elevated plasma free/bound norepinephrine (NE) concentration could be responsible for directly influencing CPC functionality. Venous blood was taken from ten healthy male subjects (25.3+/-4.4 yrs) before and 4 times after ergometry under normoxia and normobaric hypoxia (FiO2<0.15). The circulating hematopoietic stem and progenitor cell numbers were correlated with free/bound NE, free/bound epinephrine (EPI), cortisol (Co) and interleukin-6 (IL-6). Additionally, the influence of exercise-induced NE and blood lactate (La) on CPC functionality was analyzed in a randomly selected group of subjects (n = 6) in vitro under normoxia by secondary colony-forming unit granulocyte macrophage assays. Concentrations of free NE, EPI, Co and IL-6 were significantly increased post-exercise under normoxia/hypoxia. Ergometry-induced free NE concentrations found in vivo showed a significant impairment of CPC functionality in vitro under normoxia. Thus, ergometry-induced free NE was thought to trigger CPC mobilization 10 minutes post-exercise, but as previously shown impairs CPC proliferative capacity/functionality at the same time. The obtained results suggest that an ergometry-induced free NE concentration has a direct negative effect on CPC functionality. Cortisol may further influence CPC dynamics and functionality. PMID:25180783

  8. Exercise-Induced Norepinephrine Decreases Circulating Hematopoietic Stem and Progenitor Cell Colony-Forming Capacity

    PubMed Central

    Mangge, Harald; Pekovits, Karin; Fuchs, Robert; Allard, Nathalie; Schinagl, Lukas; Hofmann, Peter; Dohr, Gottfried; Wallner-Liebmann, Sandra; Domej, Wolfgang; Müller, Wolfram

    2014-01-01

    A recent study showed that ergometry increased circulating hematopoietic stem and progenitor cell (CPC) numbers, but reduced hematopoietic colony forming capacity/functionality under normoxia and normobaric hypoxia. Herein we investigated whether an exercise-induced elevated plasma free/bound norepinephrine (NE) concentration could be responsible for directly influencing CPC functionality. Venous blood was taken from ten healthy male subjects (25.3+/−4.4 yrs) before and 4 times after ergometry under normoxia and normobaric hypoxia (FiO2<0.15). The circulating hematopoietic stem and progenitor cell numbers were correlated with free/bound NE, free/bound epinephrine (EPI), cortisol (Co) and interleukin-6 (IL-6). Additionally, the influence of exercise-induced NE and blood lactate (La) on CPC functionality was analyzed in a randomly selected group of subjects (n = 6) in vitro under normoxia by secondary colony-forming unit granulocyte macrophage assays. Concentrations of free NE, EPI, Co and IL-6 were significantly increased post-exercise under normoxia/hypoxia. Ergometry-induced free NE concentrations found in vivo showed a significant impairment of CPC functionality in vitro under normoxia. Thus, ergometry-induced free NE was thought to trigger CPC mobilization 10 minutes post-exercise, but as previously shown impairs CPC proliferative capacity/functionality at the same time. The obtained results suggest that an ergometry-induced free NE concentration has a direct negative effect on CPC functionality. Cortisol may further influence CPC dynamics and functionality. PMID:25180783

  9. Comparison of Nigella sativa- and exercise-induced models of cardiac hypertrophy: structural and electrophysiological features.

    PubMed

    Al-Asoom, Lubna Ibrahim; Al-Shaikh, Basil Abdulrahman; Bamosa, Abdullah Omar; El-Bahai, Mohammad Nabil

    2014-09-01

    Exercise training is employed as supplementary therapeutic intervention for heart failure, due to its ability to induce physiological cardiac hypertrophy. In parallel, supplementation with Nigella sativa (N. sativa) was found to enhance myocardial function and induce cardiac hypertrophy. In this study, we aim to compare the morphological and electrophysiological changes associated with these patterns of cardiac hypertrophy and the possible changes upon administration of N. sativa to exercise-trained animals. Fifty-six adult Wistar rats were divided into: control, Nigella-treated (N), exercise-trained (E), and Nigella-treated-exercise-trained (NE) rats. Daily 800 mg/kg N. sativa was administered orally to N and NE. E and NE ran on treadmill, 2 h/day. At the end of 8 weeks ECG, body weight (BW), heart weight (HW), and left ventricular weight (LVW) were recorded. Hematoxylin and Eosin and periodic acid-Schiff sections were prepared to study the histology of left ventricles and to measure diameter of cardiomyocytes (Cdia). HW/BW, LVW/BW, and mean Cdia were significantly higher in all experimental animals compared to the controls. Histology showed normal cardiomyocytes with no fibrosis. ECG showed significantly lower heart rates, higher QRS amplitude, and ventricular specific potential in NE group compared to control group. Supplementation of N. sativa demonstrated a synergistic effect with exercise training as Nigella-exercise-induced cardiac hypertrophy had lower heart rate and well-matched electrical activity of the heart to its mass. Therefore, this model of cardiac hypertrophy might be introduced as a new therapeutic strategy for treatment for heart failure with superior advantages to exercise training. PMID:24448711

  10. Exercise ameliorates high fat diet induced cardiac dysfunction by increasing interleukin 10

    PubMed Central

    Kesherwani, Varun; Chavali, Vishalakshi; Hackfort, Bryan T.; Tyagi, Suresh C.; Mishra, Paras K.

    2015-01-01

    Increasing evidence suggests that a sedentary lifestyle and a high fat diet (HFD) leads to cardiomyopathy. Moderate exercise ameliorates cardiac dysfunction, however underlying molecular mechanisms are poorly understood. Increased inflammation due to induction of pro-inflammatory cytokine such as tumor necrosis factor-alpha (TNF-α) and attenuation of anti-inflammatory cytokine such as interleukin 10 (IL-10) contributes to cardiac dysfunction in obese and diabetics. We hypothesized that exercise training ameliorates HFD- induced cardiac dysfunction by mitigating obesity and inflammation through upregulation of IL-10 and downregulation of TNF-α. To test this hypothesis, 8 week old, female C57BL/6J mice were fed with HFD and exercised (swimming 1 h/day for 5 days/week for 8 weeks). The four treatment groups: normal diet (ND), HFD, HFD + exercise (HFD + Ex) and ND + Ex were analyzed for mean body weight, blood glucose level, TNF-α, IL-10, cardiac fibrosis by Masson Trichrome, and cardiac dysfunction by echocardiography. Mean body weights were increased in HFD but comparatively less in HFD + Ex. The level of TNF-α was elevated and IL-10 was downregulated in HFD but ameliorated in HFD + Ex. Cardiac fibrosis increased in HFD and was attenuated by exercise in the HFD + Ex group. The percentage ejection fraction and fractional shortening were decreased in HFD but comparatively increased in HFD + Ex. There was no difference between ND and ND + Ex for the above parameters except an increase in IL-10 level following exercise. Based on these results, we conclude that exercise mitigates HFD- induced cardiomyopathy by decreasing obesity, inducing IL-10, and reducing TNF-α in mice. PMID:25954207

  11. Physical exercise-induced changes in the core body temperature of mice depend more on ambient temperature than on exercise protocol or intensity

    NASA Astrophysics Data System (ADS)

    Wanner, Samuel Penna; Costa, Kátia Anunciação; Soares, Anne Danieli Nascimento; Cardoso, Valbert Nascimento; Coimbra, Cândido Celso

    2014-08-01

    The mechanisms underlying physical exercise-induced hyperthermia may be species specific. Therefore, the present study aimed to investigate the effects of exercise intensity and ambient temperature on the core body temperature ( T core) of running mice, which provide an important experimental model for advancing the understanding of thermal physiology. We evaluated the influence of different protocols (constant- or incremental-speed exercises), treadmill speeds and ambient temperatures ( T a) on the magnitude of exercise-induced hyperthermia. To measure T core, a telemetric sensor was implanted in the abdominal cavity of male adult Swiss mice under anesthesia. After recovering from the surgery, the animals were familiarized to running on a treadmill and then subjected to the different running protocols and speeds at two T a: 24 °C or 34 °C. All of the experimental trials resulted in marked increases in T core. As expected, the higher-temperature environment increased the magnitude of running-induced hyperthermia. For example, during incremental exercise at 34 °C, the maximal T core achieved was increased by 1.2 °C relative to the value reached at 24 °C. However, at the same T a, neither treadmill speed nor exercise protocol altered the magnitude of exercise-induced hyperthermia. We conclude that T core of running mice is influenced greatly by T a, but not by the exercise protocols or intensities examined in the present report. These findings suggest that the magnitude of hyperthermia in running mice may be regulated centrally, independently of exercise intensity.

  12. Biochemical changes on the repair of surgical bone defects grafted with biphasic synthetic micro-granular HA + β-tricalcium phosphate induced by laser and LED phototherapies assessed by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Pinheiro, Antonio Luiz B.; Soares, Luiz Guilherme P.; Marques, Aparecida Maria C.; Silveira, Landulfo

    2016-03-01

    This work aimed the assessment of the biochemical changes during bone mineralization induced by laser and LED irradiation in an animal model of bone repair using a spectral model based on Raman spectroscopy. Six groups were studied: Clot, Laser (λ780 nm, 70 mW), LED (λ850 nm +/- 10 nm, 150 mW), Biomaterial (biphasic synthetic microgranular hydroxyapatite (HA) + β-tricalcium phosphate), Laser + Biomaterial and LED + Biomaterial. When indicated, defects were further irradiated at 48 h interval during 2 wks, 20 J/cm2 per session. At 15th and 30th days, femurs were dissected and spectra of the defects were collected. Raman spectra were submitted to a model to estimate the relative amount of collagen, phosphate HA and carbonate HA, by using spectra of pure collagen, biomaterial and basal bone, respectively. At 15th days, the use of biomaterial associated to phototherapy reduced the collagen formation, whereas the amount of carbonate HA was not different in all groups. The phosphate HA was higher in the groups that received biomaterial grafts. At 30th days, it was observed an increase of collagen for the group Laser + Biomaterial, and a reduction in the carbonate HA for the LED + Biomaterial. The phosphate HA was higher for the groups LED + Biomaterial and Laser + Biomaterial, while decreased for the group Biomaterial. These results indicated that the use of Laser and LED phototherapies improved the repair of bone defects grafted with the biomaterial by increasing the collagen deposition and phosphate HA.

  13. Exercise-induced neuroprotective effects on neurodegenerative diseases: the key role of trophic factors.

    PubMed

    Campos, Carlos; Rocha, Nuno Barbosa F; Lattari, Eduardo; Paes, Flávia; Nardi, António E; Machado, Sérgio

    2016-06-01

    Age-related neurodegenerative disorders, like Alzheimer's or Parkinson's disease, are becoming a major issue to public health care. Currently, there is no effective pharmacological treatment to address cognitive impairment in these patients. Here, we aim to explore the role of exercise-induced trophic factor enhancement in the prevention or delay of cognitive decline in patients with neurodegenerative diseases. There is a significant amount of evidence from animal and human studies that links neurodegenerative related cognitive deficits with changes on brain and peripheral trophic factor levels. Several trials with elderly individuals and patients with neurodegenerative diseases report exercise induced cognitive improvements and changes on trophic factor levels including BDNF, IGF-I, among others. Further studies with healthy aging and clinical populations are needed to understand how diverse exercise interventions produce different variations in trophic factor signaling. Genetic profiles and potential confounders regarding trophic factors should also be addressed in future trials. PMID:27086703

  14. Fibroblast growth factor 21 and exercise-induced hepatic mitochondrial adaptations.

    PubMed

    Fletcher, Justin A; Linden, Melissa A; Sheldon, Ryan D; Meers, Grace M; Morris, E Matthew; Butterfield, Anthony; Perfield, James W; Thyfault, John P; Rector, R Scott

    2016-05-15

    Exercise stimulates hepatic mitochondrial adaptations; however, the mechanisms remain largely unknown. Here we tested whether FGF21 plays an obligatory role in exercise induced hepatic mitochondrial adaptations by testing exercise responses in FGF21 knockout mice. FGF21 knockout (FGF21-KO) and wild-type (WT) mice (11-12 wk of age) had access to voluntary running wheels for exercise (EX) or remained sedentary for 8 wk. FGF21 deficiency resulted in greater body weight, adiposity, serum cholesterol, insulin, and glucose concentrations compared with WT mice (P < 0.05). In addition, hepatic mitochondrial complete palmitate oxidation, β-hydroxyacyl-CoA dehydrogenase (β-HAD) activity, and nuclear content of PGC-1α were 30-50% lower in FGF21-KO mice compared with WT mice (P < 0.01). EX effectively lowered body weight, adiposity, serum triglycerides, free fatty acids, and insulin and normalized mitochondrial complete palmitate oxidation in the FGF21-KO mice, whereas the reduced hepatic β-HAD activity and lowered nuclear content of PGC-1α in FGF21-KO mice were not restored by EX. In addition, EX increased hepatic CPT-1α mRNA expression and ACC phosphorylation (a marker of increased AMPK activity) and reduced hepatic triacylglycerol content in both genotypes. However, FGF21-KO mice displayed a lower EX-induced increase in the mRNA expression of the hepatic gluconeogenic gene, PEPCK, compared with WT. In conclusion, FGF21 does not appear necessary for exercise-induced systemic and hepatic mitochondrial adaptations, but the increased adiposity, hyperinsulinemia, and impairments in hepatic mitochondrial function induced by FGF21 deficiency can be partially rescued by daily wheel running exercise. PMID:27012775

  15. Suppression of exercise-induced angina by magnesium sulfate in patients with variant angina

    SciTech Connect

    Kugiyama, K.; Yasue, H.; Okumura, K.; Goto, K.; Minoda, K.; Miyagi, H.; Matsuyama, K.; Kojima, A.; Koga, Y.; Takahashi, M.

    1988-11-01

    The effects of intravenous magnesium on exercise-induced angina were examined in 15 patients with variant angina and in 13 patients with stable effort angina and were compared with those of placebo. Symptom-limited bicycle exercise and thallium-201 myocardial scintigraphy were performed after intravenous administration of 0.27 mmol/kg body weight of magnesium sulfate and after placebo on different days. In all patients, serum magnesium levels after administration of magnesium sulfate were about twofold higher than levels after placebo. Exercise-induced angina associated with transient ST segment elevation occurred in 11 patients with variant angina receiving placebo and in only 2 of these patients receiving magnesium (p less than 0.005). On the other hand, exercise-induced angina was not suppressed by magnesium in any patient with stable effort angina. In these patients there was no significant difference in exercise duration after administration of placebo versus after administration of magnesium. The size of the perfusion defect as measured by thallium-201 scintigraphy was significantly less in patients with variant angina receiving magnesium than that in those receiving placebo (p less than 0.001), whereas it was not significantly different in patients with stable effort angina receiving placebo versus magnesium. In conclusion, exercise-induced angina is suppressed by intravenous magnesium in patients with variant angina but not in patients with stable effort angina. This beneficial effect of magnesium in patients with variant angina is most likely due to improvement of regional myocardial blood flow by suppression of coronary artery spasm.

  16. Coronary arteriography and left ventriculography during spontaneous and exercise-induced ST segment elevation in patients with variant angina

    SciTech Connect

    Matsuda, Y.; Ozaki, M.; Ogawa, H.; Naito, H.; Yoshino, F.; Katayama, K.; Fujii, T.; Matsuzaki, M.; Kusukawa, R.

    1983-09-01

    The present study is an angiographic demonstration of coronary artery spasm during both spontaneous and exercise-induced angina in three patients with variant angina. In each case, clinical, ECG, coronary angiographic, and left ventriculographic observations were made at rest, during spontaneous angina, and during exercise-induced angina. The character of chest pain was similar during spontaneous and exercise-induced episodes. ST segment elevation was present in the anterior ECG leads during both episodes. The left anterior descending coronary artery became partially or totally obstructed during both types of attacks. When coronary spasm was demonstrated during both types of attacks, left ventriculography disclosed akinetic or dyskinetic wall motion in the area supplied by the involved artery. In those patients with reproducible exercise-induced ST segment elevation and chest pain, thallium-201 scintigraphy showed areas of reversible anteroseptal hypoperfusion. Thus in selected patients exercise-induced attacks of angina were similar to spontaneous episodes.

  17. Effects of propranolol and nifedipine on exercise-induced attack in patients variant angina: assessment by exercise thallium-201 myocardial scintigraphy with quantitative rotational tomography

    SciTech Connect

    Kugiyama, K.; Yasue, H.; Horio, Y.; Morikami, Y.; Fujii, H.; Koga, Y.; Kojima, A.; Takahashi, M.

    1986-08-01

    To examine the effects of propranolol and nifedipine on exercise-induced attack in patients with variant angina, exercise /sup 201/Tl myocardial scintigraphy with quantitative analysis by emission-computed tomography was performed in 20 patients with variant angina after oral propranolol (80 mg), nifedipine (20 mg), and placebo. Exercise-induced attack occurred in 11 patients on placebo, in 14 on propranolol, and in none on nifedipine. The exercise duration was significantly shorter in those on propranolol (p less than .05), but significantly longer in patients on nifedipine (p less than .05) than in those on placebo. The peak rate-pressure product was significantly lower in patients on propranolol (p less than .01), but did not change in those on nifedipine, as compared with that in patients on placebo. The size of the perfusion defect as measured by /sup 201/Tl tomography was significantly greater in patients on propranolol (p less than .05), but significantly less in those on nifedipine (p less than .01) than in those on placebo. In conclusion, propranolol does not suppress but rather may aggravate exercise-induced attack in patients with variant angina, while nifedipine suppresses it. This unfavorable effect of propranolol on exercise-induced attack in patients with variant angina is likely to be due to a reduction of regional myocardial blood flow.

  18. The role of exercise-induced myokines in muscle homeostasis and the defense against chronic diseases.

    PubMed

    Brandt, Claus; Pedersen, Bente K

    2010-01-01

    Chronic inflammation is involved in the pathogenesis of insulin resistance, atherosclerosis, neurodegeneration, and tumour growth. Regular exercise offers protection against type 2 diabetes, cardiovascular diseases, colon cancer, breast cancer, and dementia. Evidence suggests that the protective effect of exercise may to some extent be ascribed to the antiinflammatory effect of regular exercise. Here we suggest that exercise may exert its anti-inflammatory effect via a reduction in visceral fat mass and/or by induction of an anti-inflammatory environment with each bout of exercise. According to our theory, such effects may in part be mediated via muscle-derived peptides, so-called "myokines". Contracting skeletal muscles release myokines with endocrine effects, mediating direct anti-inflammatory effects, and/or specific effects on visceral fat. Other myokines work locally within the muscle and exert their effects on signalling pathways involved in fat oxidation and glucose uptake. By mediating anti-inflammatory effects in the muscle itself, myokines may also counteract TNF-driven insulin resistance. In conclusion, exercise-induced myokines appear to be involved in mediating both systemic as well as local anti-inflammatory effects. PMID:20224659

  19. Exercise-induced seizures and lateral asymmetry in patients with temporal lobe epilepsy☆☆☆

    PubMed Central

    Kamel, Jordan T.; Badawy, Radwa A.B.; Cook, Mark J.

    2014-01-01

    Objective The objective of this case report is to better characterize the clinical features and potential pathophysiological mechanisms of exercise-induced seizures. Methods We report a case series of ten patients from a tertiary epilepsy center, where a clear history was obtained of physical exercise as a reproducible trigger for seizures. Results The precipitating type of exercise was quite specific for each patient, and various forms of exercise are described including running, swimming, playing netball, dancing, cycling, weight lifting, and martial arts. The level of physical exertion also correlated with the likelihood of seizure occurrence. All ten patients had temporal lobe abnormalities, with nine of the ten patients having isolated temporal lobe epilepsies, as supported by seizure semiology, EEG recordings, and both structural and functional imaging. Nine of the ten patients had seizures that were lateralized to the left (dominant) hemisphere. Five patients underwent surgical resection, with no successful long-term postoperative outcomes. Conclusions Exercise may be an underrecognized form of reflex epilepsy, which tended to be refractory to both medical and surgical interventions in our patients. Almost all patients in our cohort had seizures localizing to the left temporal lobe. We discuss potential mechanisms by which exercise may precipitate seizures, and its relevance regarding our understanding of temporal lobe epilepsy and lateralization of seizures. Recognition of, as well as advice regarding avoidance of, known triggers forms an important part of management of these patients. PMID:25667863

  20. Superoxide dismutase derivative prevents oxidative damage in liver and kidney of rats induced by exhausting exercise.

    PubMed

    Radák, Z; Asano, K; Inoue, M; Kizaki, T; Oh-Ishi, S; Suzuki, K; Taniguchi, N; Ohno, H

    1996-01-01

    To prevent oxidative tissue damage induced by strenuous exercise in the liver and kidney superoxide dismutase derivative (SM-SOD), which circulated bound to albumin with a half-life of 6 h, was injected intraperitoneally into rats. Exhausting treadmill running caused a significant increase in the activities of xanthine oxidase (XO), and glutathione peroxidase (GPX) in addition to concentrations of thiobarbituric acid-reactive substances (TBARS) in hepatic tissue immediately after running. There was a definite increase in the immunoreactive content of mitochondrial superoxide dismutase (Mn-SOD) 1 day after the running. Meanwhile, the TBARS concentration in the kidney was markedly elevated 3 days after running. The activities of GPX, and catalase in the kidney increased significantly immediately and on days 1 and 3 following the test. The immunoreactive content of Mn-SOD also increased 1 day after running. The exercise induced no significant changes in immunoreactive Cu, Zn-SOD content in either tissue. The administration of SM-SOD provided effective protection against lipid peroxidation, and significantly attenuated the alterations in XO and all the anti-oxidant enzymes, measured. In summary, the present data would suggest that exhausting exercise may induce XO-derived oxidative damage in the liver, while the increase in lipid peroxidation in the kidney might be the result of washout-dependent accumulation of peroxidised metabolites. We found that the administration of SM-SOD provided excellent protection against exercise-induced oxidative stress in both liver and kidney. PMID:8820884

  1. Exercise-induced haemoptysis as a rare presentation of a rare lung disease.

    PubMed

    Mihalek, Andrew D; Haney, Carissa; Merino, Maria; Roy-Chowdhuri, Sinchita; Moss, Joel; Olivier, Kenneth N

    2016-09-01

    Amyloid primarily affecting the lungs is a seldom seen clinical entity. This case discusses the work-up of a patient presenting with exercise-induced haemoptysis and diffuse cystic lung disease on radiographic imaging. The common clinical and radiographic findings of diffuse cystic lung diseases as well as a brief overview of pulmonary amyloid are presented. PMID:27272655

  2. Green Tea Catechin Consumption Enhances Exercise-Induced Abdominal Fat Loss

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aim: This study evaluated the influence of a green tea catechin beverage on body composition and fat distribution in overweight and obese adults during exercised-induced weight loss. Methods: Participants (N=132) were randomly assigned to receive a 500 mL beverage containing approximately 625 mg of...

  3. Unusual Case of Exercise-Induced ST Segment Elevation Alternans: Successful Treatment with Transluminal Angioplasty

    PubMed Central

    Mammen, George; Krajcer, Zvonimir; Leachman, Robert D.

    1983-01-01

    Alternans of the ST segment is sometimes observed in experimental studies but is rarely seen in the clinical setting. Described is a case of exercise-induced ST segment elevation alternans that was successfully treated with transluminal coronary artery angioplasty. Theories regarding the cause and mechanism of this phenomenon are discussed. Images PMID:15227140

  4. Moderate exercise prevents neurodegeneration in D-galactose-induced aging mice.

    PubMed

    Li, Li; Xu, Meng; Shen, Bo; Li, Man; Gao, Qian; Wei, Shou-Gang

    2016-05-01

    D-galactose has been widely used in aging research because of its efficacy in inducing senescence and accelerating aging in animal models. The present study investigated the benefits of exercise for preventing neurodegeneration, such as synaptic plasticity, spatial learning and memory abilities, in mouse models of aging. D-galactose-induced aging mice were administered daily subcutaneous injections of D-galactose at the base of the neck for 10 consecutive weeks. Then, the mice were subjected to exercise training by running on a treadmill for 6 days a week. Shortened escape latency in a Morris water maze test indicated that exercise improved learning and memory in aging mice. The ameliorative changes were likely induced by an upregulation of Bcl-2 and brain-derived neurotrophic factor, the repression of apoptosis factors such as Fas and Bax, and an increase in the activity of glucose transporters-1 and 4. The data suggest moderate exercise may retard or inhibit neurodegeneration in D-galactose-induced aging mice. PMID:27335566

  5. Increased Protein Maintains Nitrogen Balance during Exercise-Induced Energy Deficit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    PURPOSE: This study examined how a high-protein diet affected nitrogen balance and protein turnover during an exercise-induced energy deficit. METHODS: Twenty-two men completed a 4-d (D1-4) baseline period (BL) of an energy balance diet while maintaining usual physical activity level, followed by 7 ...

  6. Influence of artistic gymnastics on iron nutritional status and exercise-induced hemolysis in female athletes.

    PubMed

    Sureira, Thaiz Mattos; Amancio, Olga Silverio; Pellegrini Braga, Josefina Aparecida

    2012-08-01

    This study evaluates the relationship between body iron losses and gains in artistic gymnastics female athletes. It shows that despite the low iron intake and exercise-induced hemolysis, iron deficiency or iron-deficiency anemia does not occur, but partial changes in the hematological profile do. The hypothesis that gymnasts' nutritional behavior contributes to anemia, which may be aggravated by exercise-induced hemolysis, led to this cross-sectional study, conducted with 43 female artistic gymnasts 6-16 yr old. The control group was formed by 40 nontraining girls, paired by age. Hemogram, serum iron, ferritin, soluble transferrin receptor, haptoglobin, total and fractional bilirubin, Type I urine, and parasitologic and occult fecal blood tests were evaluated. The athletes presented mean hematimetric and serum iron values (p = .020) higher than those of the control group. The bilirubin result discarded any hemolytic alteration in both groups. The haptoglobin results were lower in the athlete group (p = .002), confirming the incidence of exercise-induced hemolysis. Both groups presented low iron intake. The results suggest that artistic gymnastics practice leads to exercise-induced hemolysis and partially changes the hematological profile, although not causing iron deficiency or iron-deficiency anemia, even in the presence of low iron intake. PMID:22645172

  7. Moderate exercise prevents neurodegeneration in D-galactose-induced aging mice

    PubMed Central

    Li, Li; Xu, Meng; Shen, Bo; Li, Man; Gao, Qian; Wei, Shou-gang

    2016-01-01

    D-galactose has been widely used in aging research because of its efficacy in inducing senescence and accelerating aging in animal models. The present study investigated the benefits of exercise for preventing neurodegeneration, such as synaptic plasticity, spatial learning and memory abilities, in mouse models of aging. D-galactose-induced aging mice were administered daily subcutaneous injections of D-galactose at the base of the neck for 10 consecutive weeks. Then, the mice were subjected to exercise training by running on a treadmill for 6 days a week. Shortened escape latency in a Morris water maze test indicated that exercise improved learning and memory in aging mice. The ameliorative changes were likely induced by an upregulation of Bcl-2 and brain-derived neurotrophic factor, the repression of apoptosis factors such as Fas and Bax, and an increase in the activity of glucose transporters-1 and 4. The data suggest moderate exercise may retard or inhibit neurodegeneration in D-galactose-induced aging mice. PMID:27335566

  8. [Exercise-induced ST segment shift in vasospastic angina with special reference to comparisons between treadmill and bicycle ergometer exercise testings].

    PubMed

    Kasai, A; Yamakado, T; Masuda, T; Aoki, T; Futagami, Y; Hamada, M; Nakano, T

    1991-01-01

    To assess the difference between cardiovascular responses to treadmill exercise (TM) and those to bicycle ergometer exercise (EM) in provoking coronary spasm, we compared the ST segment shifts (elevation or depression) during TM and EM in 67 patients with vasospastic angina. Coronary artery spasm was demonstrated on angiography. Both TM and EM were performed on the same day during a medication-free period. For both tests, multistage, symptom-limited exercise protocols were used; EM in the morning and TM in the afternoon. The results obtained were as follows: 1. Rate-pressure products at peak exercise during TM and EM were similar. Systolic blood pressure levels at peak exercise were higher during EM than during TM (p < 0.01). The patients' heart rates at peak exercise were higher during TM than during EM (p < 0.01). Diastolic blood pressure levels at peak exercise were higher during EM than during TM (p < 0.05). 2. Exercise-induced ST elevation occurred more frequently with TM than with EM (19% vs 9%, p < 0.05). 3. Exercise-induced ST depression was provided in 27 patients during TM and in 13 during EM (40% vs 19%, p < 0.01). Among 45 patients without significant lesions, ST depression occurred in 19 during TM, but in only 7 during EM (42% vs 16%, p < 0.01). In conclusion, coronary spasm seemed to occur more frequently with TM than with EM. The mechanism causing such difference remains to be elucidated, however, we speculate that the difference between TM and EM as to enhanced autonomous nervous system activity and coronary perfusion exercise may be related to the difference in the incidence of coronary spasm. PMID:1841908

  9. Exercise-induced promotion of hippocampal cell proliferation requires beta-endorphin.

    PubMed

    Koehl, M; Meerlo, P; Gonzales, D; Rontal, A; Turek, F W; Abrous, D N

    2008-07-01

    Adult hippocampal neurogenesis is influenced by a variety of stimuli, including exercise, but the mechanisms by which running affects neurogenesis are not yet fully understood. Because beta-endorphin, which is released in response to exercise, increases cell proliferation in vitro, we hypothesized that it could exert a similar effect in vivo and mediate the stimulatory effects of running on neurogenesis. We thus analyzed the effects of voluntary wheel-running on adult neurogenesis (proliferation, differentiation, survival/death) in wild-type and beta-endorphin-deficient mice. In wild-type mice, exercise promoted cell proliferation evaluated by sacrificing animals 24 h after the last 5-bromo-2'-deoxyuridine (BrdU) pulse and by using endogenous cell cycle markers (Ki67 and pH(3)). This was accompanied by an increased survival of 4-wk-old BrdU-labeled cells, leading to a net increase of neurogenesis. Beta-endorphin deficiency had no effect in sedentary mice, but it completely blocked the running-induced increase in cell proliferation; this blockade was accompanied by an increased survival of 4-wk-old cells and a decreased cell death. Altogether, adult neurogenesis was increased in response to exercise in knockout mice. We conclude that beta-endorphin released during running is a key factor for exercise-induced cell proliferation and that a homeostatic balance may regulate the final number of new neurons. PMID:18263701

  10. Enhanced vagal modulation and exercise induced ischaemia of the inferoposterior myocardium

    PubMed Central

    Kawasaki, T; Azuma, A; Kuribayashi, T; Taniguchi, T; Asada, S; Kamitani, T; Kawasaki, S; Matsubara, H; Sugihara, H

    2006-01-01

    Objective To determine whether the Bezold‐Jarisch reflex or enhancement of vagal nerves, which are preferentially distributed in the inferoposterior myocardium, results from exercise induced ischaemia in this region. Methods On the basis of exercise myocardial scintigraphy and coronary angiography, 145 patients were classified as follows: group I, 34 patients with inferoposterior ischaemia; group A, 32 with anterior ischaemia; and control, 79 without ischaemia. The relation between ischaemic areas and ECG leads with ST segment changes and vagal modulation assessed by heart rate variability (HRV) (high frequency (HF) component (0.15–0.40 Hz) and coefficient of HF component variance (CCVHF), which is the square root of HF divided by mean RR interval) were assessed. Results The rate of ST segment depression in any lead did not differ between group I and group A. HF and CCVHF were similar before exercise but higher in group I than in group A and the control group after exercise (mean (SEM) HF: 94 (17) ms2, 41 (7) ms2, and 45 (6) ms2, respectively, p  =  0.021; CCVHF: 1.18 (0.09)%, 0.81 (0.07)%, and 0.89 (0.05)%, p  = 0.0053). Furthermore, the percentage change in CCVHF before and after exercise was higher in group I than in group A or controls (mean (SEM) 22 (10)%, −24 (4)%, and −21 (3)%, p < 0.0001). The optimal cut off for diagnosis of inferoposterior ischaemia was −5% with a sensitivity of 74%, specificity 75%, and accuracy 75%. Conclusions Vagal modulation as assessed by HRV analysis was enhanced in association with exercise induced inferoposterior ischaemia. Exercise ECG testing combined with HRV analysis would increase accuracy in the diagnosis of ischaemic areas in selected patients with angina pectoris. PMID:15939725

  11. Exercise prevents leptin-induced increase in blood pressure in Sprague-Dawley rats.

    PubMed

    Farhana, K; Effendi, I; Caszo, Brinnell; Satar, Nuraliza Abdul; Singh, H J

    2014-06-01

    Although leptin has been shown to increase blood pressure (BP), it is however unclear if this increase can be prevented by exercise. This study therefore investigated the effect of leptin treatment with concurrent exercise on blood pressure (BP), sodium output, and endothelin-1 (ET-1) levels in normotensive rats. Male Sprague-Dawley rats weighing 250-270 g were divided into four groups consisting of a control group (n = 6), leptin-treated (n = 8), non-leptin-treated exercise group (n = 8), and a leptin-treated exercise group (n = 8). Leptin was given subcutaneously daily for 14 days (60 μg/kg/day). Animals were exercised on a treadmill for 30 min at a speed of 0.5 m/s and at 5° incline four times per week. Measurement of systolic blood pressure (SBP) and collection of urine samples for estimation of sodium and creatinine was done once a week. Serum samples were collected at the end of the experiment for determination of sodium, creatinine and ET-1. At day 14, mean SBP and serum ET-1 level in the leptin-treated group was significantly higher than that in the control group whereas mean SBP and serum ET-1 level was significantly lower in the leptin-treated exercise group than those in leptin-treated and control groups. Creatinine clearance, urinary sodium excretion, and urine output were not different between the four groups. Regular treadmill exercise prevents leptin-induced increases in SBP in rats, which might in part result from increased urinary sodium excretion and preventing the leptin-induced increases in serum ET-1 concentration. PMID:24711061

  12. Interaction of myocardial insulin receptor and IGF receptor signaling in exercise-induced cardiac hypertrophy

    PubMed Central

    Ikeda, Hiroyuki; Shiojima, Ichiro; Ozasa, Yukako; Yoshida, Masashi; Holzenberger, Martin; Kahn, C Ronald; Walsh, Kenneth; Igarashi, Takashi; Abel, E Dale; Komuro, Issei

    2016-01-01

    Insulin-like growth factor-1 (IGF-1) signaling has recently been implicated in the development of cardiac hypertrophy after long-term endurance training, via mechanisms that may involve energetic stress. Given the potential overlap of insulin and IGF-1 signaling we sought to determine if both signaling pathways could contribute to exercise-induced cardiac hypertrophy following shorter-term exercise training. Studies were performed in mice with cardiac-specific IGF-1 receptor (IGF1R) knockout (CIGFRKO), mice with cardiac-specific insulin receptor (IR) knockout (CIRKO), CIGFRKO mice that lacked one IR allele in cardiomyocytes (IGFR−/−IR+/−), and CIRKO mice that lacked one IGF1R allele in cardiomyocytes (IGFR+/−IR−/−). Intravenous administration of IGF-1 or 75 hours of swimming over 4 weeks increased IGF1R tyrosine phosphorylation in the heart in control and CIRKO mice but not in CIGFRKO mice. Intriguingly, IR tyrosine phosphorylation in the heart was also increased following IGF-1 administration or exercise training in control and CIGFRKO mice but not in CIRKO mice. The extent of cardiac hypertrophy following exercise training in CIGFRKO and CIRKO mice was comparable to that in control mice. In contrast, exercise-induced cardiac hypertrophy was significantly attenuated in IGFR−/−IR+/− and IGFR+/−IR−/− mice. Thus, IGF-1 and exercise activates both IGF1R and IR in the heart, and IGF1R- and IR-mediated signals may serve redundant roles in the hypertrophic responses of the heart to exercise training. PMID:19744489

  13. Prior exercise training blunts short-term high-fat diet-induced weight gain.

    PubMed

    Snook, Laelie A; MacPherson, Rebecca E K; Monaco, Cynthia M F; Frendo-Cumbo, Scott; Castellani, Laura; Peppler, Willem T; Anderson, Zachary G; Buzelle, Samyra L; LeBlanc, Paul J; Holloway, Graham P; Wright, David C

    2016-08-01

    High-fat diets rapidly cause weight gain and glucose intolerance. We sought to determine whether these changes could be mitigated with prior exercise training. Male C57BL/6J mice were exercise-trained by treadmill running (1 h/day, 5 days/wk) for 4 wk. Twenty-four hours after the final bout of exercise, mice were provided with a high-fat diet (HFD; 60% kcal from lard) for 4 days, with no further exercise. In mice fed the HFD prior to exercise training, the results were blunted weight gain, reduced fat mass, and a slight attenuation in glucose intolerance that was mirrored by greater insulin-induced Akt phosphorylation in skeletal muscle compared with sedentary mice fed the HFD. When ad libitum-fed sedentary mice were compared with sedentary high-fat fed mice that were calorie restricted (-30%) to match the weight gain of the previously trained high-fat fed mice, the same attenuated impairments in glucose tolerance were found. Blunted weight gain was associated with a greater capacity to increase energy expenditure in trained compared with sedentary mice when challenged with a HFD. Although mitochondrial enzymes in white adipose tissue and UCP-1 protein content in brown adipose tissue were increased in previously exercised compared with sedentary mice fed a HFD, ex vivo mitochondrial respiration was not increased in either tissue. Our data suggest that prior exercise training attenuates high-fat diet-induced weight gain and glucose intolerance and is associated with a greater ability to increase energy expenditure in response to a high-fat diet. PMID:27101294

  14. Tryptophan-induced central fatigue in exercising rats is related to serotonin content in preoptic area.

    PubMed

    Soares, Danusa Dias; Coimbra, Cândido Celso; Marubayashi, Umeko

    2007-03-30

    To assess the effects of increased hypothalamic tryptophan (TRP) availability on 5-HT content in preoptic area on thermoregulation and work production during exercise on treadmill, 20.3 microM of L-TRP (n=7) or 0.15M NaCl (n=6) was injected into the lateral cerebral ventricle of male Wistar rats immediately before the animals started running (18 m min(-1) 5% inclination). Exercise time to fatigue (min), and workload (kgm) were analysed. Core temperature was measured by telemetry. At fatigue, brains were quickly removed and preoptic area (POA), hypothalamus (HP), frontal cortex (FC), hippocampi (HC) were rapidly dissected and frozen immediately in dry ice. Serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were measured by HPLC. TRP-exercised rats showed the highest content of 5-HT in the POA and the lowest in the hippocampi compared to the rested and SAL-exercised rats. An inverse relationship between TF and a direct correlation with body temperature changes and POA-5HT levels were observed. A correlation between HC 5-HT content and TF was also found. However, there was no correlation between HC 5-HT content and changes in Tb at fatigue. Finally, our results bring further evidences that increased 5-HT content in POA is involved with an increase in heat production during exercise. In addition, the direct correlation of 5-HT level in hippocampi and TF of TRP-exercised rats suggests that this brain area is also related to motor activity control during exercise. In conclusion, our data indicated that tryptophan-induced central fatigue in exercising rats is related to serotonin content in preoptic area. PMID:17280786

  15. The effects of physical exercise on the cigarette smoke-induced pulmonary oxidative response.

    PubMed

    Menegali, Bruno T; Nesi, Renata T; Souza, Priscila S; Silva, Luciano A; Silveira, Paulo C L; Valença, Samuel S; Pinho, Ricardo A

    2009-12-01

    Studies have shown that the oxidative power of cigarettes is related to the pathogenesis of several pulmonary diseases and that regular physical exercise contributes significantly to reducing the deleterious effects of cigarettes. The objective of the present study was to investigate the therapeutic effects of physical exercise on histological and oxidative stress markers in animals exposed to cigarette smoke. Thirty-six male, eight-week-old C57BL-6 mice were divided into four groups (n = 9 for each group): control, exercise, cigarette smoke, and cigarette smoke plus exercise. The cigarette smoke (CS) groups were exposed to cigarette smoke 3 times/day (4 cigarettes/session) for 60 consecutive days. The exercise groups were submitted to swimming physical training 5 days/week for eight weeks. Forty-eight hours after the last exercise and cigarette exposure, the animals were sacrificed using cervical traction. The right lung was removed, processed, and stored for future analysis. In addition to the analysis of collagen content (hydroxyproline), oxidant production (anion superoxide), antioxidant enzyme activity (SOD and CAT), and lipid and protein oxidative damage (TBARS and Carbonylation), histological and morphological studies were performed. The results revealed that the animals exposed to cigarette smoke showed enlargement and destruction of the alveolar septum and increases in the numbers of macrophages and neutrophils, as well as in the amount of collagen. Our results also showed a decrease in the volume density of elastic fibers and an increase in the volume density of airspaces. However, physical exercise partially improved these markers. Additionally, physical exercise decreased oxidant production and increased the activity of the enzymatic antioxidant defense system, but did not reverse lipid and protein oxidative damage induced by cigarette smoke. These results suggest that physical training partially improves histological and oxidative stress parameters in

  16. [Practical advice for exercise-induced asthma in children: experience of the exercise training centre of Necker-Enfants malades hospital].

    PubMed

    Karila, C; Fuchs-Climent, D; Clairicia, M; Leborgne, P; Salort, M; De Blic, J; Scheinmann, P

    2005-01-01

    Now, to care exercise-induced asthma is not only to prescribe drugs. It is a global and interdisciplinary approach: the pulmonary rehabilitation, matching a therapeutic education and a physical training, with the goal of promoting a regular physical activity in the asthmatic child, achieving physiological benefits and improvement of quality of life. Getting from the experience of Necker-Enfants Malades Hospital's Training Centre, a few advises encourage the physical practice of the asthmatic child, and decrease risks of exercise-induced asthma: optimisation of treatments;progressive beginning and end of exercises; use of the diaphragmatic breathing, keeping up with the exercise; use of the ventilatory threshold (or dysponea threshold) as intensity of the aerobic training; practice of different activities promoting play and conviviality in sports and allowing the integration of sports in the daily life of the asthmatic child. PMID:15653067

  17. Voluntary exercise does not ameliorate spatial learning and memory deficits induced by chronic administration of nandrolone decanoate in rats.

    PubMed

    Tanehkar, Fatemeh; Rashidy-Pour, Ali; Vafaei, Abbas Ali; Sameni, Hamid Reza; Haghighi, Saeed; Miladi-Gorji, Hossien; Motamedi, Fereshteh; Akhavan, Maziar Mohammad; Bavarsad, Kowsar

    2013-01-01

    Chronic exposure to the anabolic androgenic steroids (AAS) nandrolone decanoate (ND) in supra-physiological doses is associated with learning and memory impairments. Given the well-known beneficial effects of voluntary exercise on cognitive functions, we examined whether voluntary exercise would improve the cognitive deficits induced by chronic administration of ND. We also investigated the effects of ND and voluntary exercise on hippocampal BDNF levels. The rats were randomly distributed into 4 experimental groups: the vehicle-sedentary group, the ND-sedentary group, the vehicle-exercise group, and the ND-exercise group. The vehicle-exercise and the ND-exercise groups were allowed to freely exercise in a running wheel for 15 days. The vehicle-sedentary and the ND-sedentary groups were kept sedentary for the same period. Vehicle or ND injections were started 14 days prior to the voluntary exercise and continued throughout the 15 days of voluntary exercise. After the 15-day period, the rats were trained and tested on a water maze spatial task using four trials per day for 5 consecutive days followed by a probe trial two days later. Exercise significantly improved performance during both the training and retention of the water maze task, and enhanced hippocampal BDNF. ND impaired spatial learning and memory, and this effect was not rescued by exercise. ND also potentiated the exercise-induced increase in hippocampal BDNF levels. These results seem to indicate that voluntary exercise is unable to improve the disruption of cognitive functions by chronic ND. Moreover, increased levels of BDNF may play a role in ND-induced impairments in learning and memory. The harmful effects of ND and other AAS on learning and memory should be taken into account when athletes decide to use AAS for performance or body image improvement. PMID:23068768

  18. Effect of exercise-induced neurogenesis on cognitive function deficit in a rat model of vascular dementia

    PubMed Central

    CHOI, DONG-HEE; LEE, KYOUNG-HEE; LEE, JONGMIN

    2016-01-01

    Chronic cerebral hypoperfusion (CCH) is strongly correlated with progressive cognitive decline in neurological diseases, such as vascular dementia (VaD) and Alzheimer's disease. Exercise can enhance learning and memory, and delay age-related cognitive decline. However, exercise-induced hippocampal neurogenesis in experimental animals submitted to CCH has not been investigated. The present study aimed to investigate whether hippocampal neurogenesis induced by exercise can improve cognitive deficit in a rat model of VaD. Male Wistar rats (age, 8 weeks; weight, 292±3.05 g; n=12–13/group) were subjected to bilateral common carotid artery occlusion (2VO) or sham-surgery and each group was then subdivided randomly into no exercise and treadmill exercise groups. Exercise groups performed treadmill exercise daily at 15 m/min for 30 min for 4 weeks from the third to the seventh week after 2VO. It was demonstrated that the number of neural progenitor cells and mature neurons in the subgranular zone of 2VO rats was increased by exercise, and cognitive impairment in 2VO rats was attenuated by treadmill exercise. In addition, mature brain-derived neurotrophic factor (BDNF) levels in the hippocampus were increased in the exercise groups. Thus the present study suggests that exercise delays cognitive decline by the enhancing neurogenesis and increasing BDNF expression in the context of VaD. PMID:26934837

  19. Protective effects of forced exercise against methylphenidate-induced anxiety, depression and cognition impairment in rat

    PubMed Central

    Motaghinejad, Majid; Motevalian, Manijeh; Larijani, Setare Farokhi; Khajehamedi, Zohreh

    2015-01-01

    Background: Methylphenidate (MPH), a neural stimulant, can cause damages to brain; the chronic neurochemical and behavioral effects of MPH remain unclear. Exercise lowers stress and anxiety and can act as non-pharmacologic neuroprotective agent. In this study protective effects of exercise in MPH-induced anxiety, depression and cognition impairment were investigated. Materials and Methods: Seventy adult male rats were divided randomly into five groups. Group 1 served as negative control, received normal saline (0.2 ml/rat) for 21 days, group 2 and 3 (as positive controls) received MPH (10 and 20 mg/kg) for 21 days. Groups 4 and 5 concurrently were treated with MPH (10 and 20 mg/kg) and forced exercise for 21 days. On day 21, Elevated Plus Maze (EPM), Open Field Test (OFT), Forced Swim Test (FST) and Tail Suspension Test (TST) were used to investigate the level of anxiety and depression in animals. In addition between 17th and 21th days, Morris Water Maze (MWM) was applied to evaluate the effect of MPH on spatial learning and memory. Results: MPH-treated animals indicated a reflective depression and anxiety in a dose-dependent manner in FST, EPM and TST which were significantly different from the control group and also can significantly attenuate the motor activity and anxiety in OFT. Forced exercise by treadmill can attenuate MPH-induced anxiety, depression and motor activity alteration in OFT. MPH also can disturb learning and memory in MWM and forced exercise can neutralize this effect of MPH. Conclusion: We conclude that forced exercise can be protective in brain against MPH-induced anxiety, depression and cognition alteration. PMID:26322282

  20. The Nuclear Receptor, Nor-1, Induces the Physiological Responses Associated With Exercise.

    PubMed

    Goode, Joel M; Pearen, Michael A; Tuong, Zewen K; Wang, Shu-Ching M; Oh, Tae Gyu; Shao, Emily X; Muscat, George E O

    2016-06-01

    Skeletal muscle remodels metabolic capacity, contractile and exercise phenotype in response to physiological demands. This adaptive remodeling response to physical activity can ameliorate/prevent diseases associated with poor diet and lifestyle. Our previous work demonstrated that skeletal muscle-specific transgenic expression of the neuron-derived orphan nuclear receptor, Nor-1 drives muscle reprogramming, improves exercise endurance, and oxidative metabolism. The current manuscript investigates the association between exercise, Nor-1 expression and the role of Nor-1 in adaptive remodeling. We demonstrate that Nor-1 expression is induced by exercise and is dependent on calcium/calcineurin signaling (in vitro and in vivo). Analysis of fatigue-resistant transgenic mice that express Nor-1 in skeletal muscle revealed increased hypertrophy and vascularization of muscle tissue. Moreover, we demonstrate that transgenic Nor-1 expression is associated with increased intracellular recycling, ie, autophagy, involving 1) increased expression of light chain 3A or LC3A-II, autophagy protein 5, and autophagy protein 12 in quadriceps femoris muscle extracts from Tg-Nor-1 (relative to Wild-type (WT) littermates); 2) decreased p62 expression indicative of increased autophagolysosome assembly; and 3) decreased mammalian target of rapamycin complex 1 activity. Transfection of LC3A-GFP-RFP chimeric plasmid demonstrated that autophagolysosome formation was significantly increased by Nor-1 expression. Furthermore, we demonstrated a single bout of exercise induced LC3A-II expression in skeletal muscle from C57BL/6 WT mice. This study, when combined with our previous studies, demonstrates that Nor-1 expression drives multiple physiological changes/pathways that are critical to the beneficial responses of muscle to exercise and provides insights into potential pharmacological manipulation of muscle reprogramming for the treatment of lifestyle induced chronic diseases. PMID:27144290

  1. Size-dependent cytotoxicity of Fe3O4 nanoparticles induced by biphasic regulation of oxidative stress in different human hepatoma cells

    PubMed Central

    Xie, Yuexia; Liu, Dejun; Cai, Chenlei; Chen, Xiaojing; Zhou, Yan; Wu, Liangliang; Sun, Yongwei; Dai, Huili; Kong, Xianming; Liu, Peifeng

    2016-01-01

    The application of Fe3O4 nanoparticles (NPs) has made great progress in the diagnosis of disease and in the drug delivery system for cancer therapy, but the relative mechanisms of potential toxicity induced by Fe3O4 have not kept pace with its development in the application, which has hampered its further clinical application. In this article, we used two kinds of human hepatoma cell lines, SK-Hep-1 and Hep3B, to investigate the cytotoxic effects and the involved mechanisms of small Fe3O4 NPs with different diameters (6 nm, 9 nm, and 14 nm). Results showed that the size of NPs effectively influences the cytotoxicity of hepatoma cells: 6 nm Fe3O4 NPs exhibited negligible cytotoxicity and 9 nm Fe3O4 NPs affected cytotoxicity via cellular mitochondrial dysfunction and by inducing necrosis mediated through the mitochondria-dependent intracellular reactive oxygen species generation. Meanwhile, 14 nm Fe3O4 NPs induced cytotoxicity by impairing the integrity of plasma membrane and promoting massive lactate dehydrogenase leakage. These results explain the detailed mechanism of different diameters of small Fe3O4 NPs-induced cytotoxicity. We anticipate that this study will provide different insights into the cytotoxicity mechanism of Fe3O4 NPs, so as to make them safer to use in clinical application. PMID:27536098

  2. Effects of ascorbic acid on copper-induced oxidative changes in human erythrocytes: example of a biphasic dose-response relationship

    SciTech Connect

    Kemp, J.; Calabrese, E.J.

    1985-01-01

    In an in vitro study, ascorbic acid reduced the occurrence of copper acetate-induced oxidative stress in human erythrocytes at biologically relevant concentrations (0.06 - 0.25 mM) while enhancing oxidative changes (i.e., changes in methemoglobin (METHB) and reduced glutathione (GSH)) at higher levels of exposure (>1.0 mM).

  3. Size-dependent cytotoxicity of Fe3O4 nanoparticles induced by biphasic regulation of oxidative stress in different human hepatoma cells.

    PubMed

    Xie, Yuexia; Liu, Dejun; Cai, Chenlei; Chen, Xiaojing; Zhou, Yan; Wu, Liangliang; Sun, Yongwei; Dai, Huili; Kong, Xianming; Liu, Peifeng

    2016-01-01

    The application of Fe3O4 nanoparticles (NPs) has made great progress in the diagnosis of disease and in the drug delivery system for cancer therapy, but the relative mechanisms of potential toxicity induced by Fe3O4 have not kept pace with its development in the application, which has hampered its further clinical application. In this article, we used two kinds of human hepatoma cell lines, SK-Hep-1 and Hep3B, to investigate the cytotoxic effects and the involved mechanisms of small Fe3O4 NPs with different diameters (6 nm, 9 nm, and 14 nm). Results showed that the size of NPs effectively influences the cytotoxicity of hepatoma cells: 6 nm Fe3O4 NPs exhibited negligible cytotoxicity and 9 nm Fe3O4 NPs affected cytotoxicity via cellular mitochondrial dysfunction and by inducing necrosis mediated through the mitochondria-dependent intracellular reactive oxygen species generation. Meanwhile, 14 nm Fe3O4 NPs induced cytotoxicity by impairing the integrity of plasma membrane and promoting massive lactate dehydrogenase leakage. These results explain the detailed mechanism of different diameters of small Fe3O4 NPs-induced cytotoxicity. We anticipate that this study will provide different insights into the cytotoxicity mechanism of Fe3O4 NPs, so as to make them safer to use in clinical application. PMID:27536098

  4. Food-dependent exercise-induced anaphylaxis due to wheat in a young woman.

    PubMed

    Ahanchian, Hamid; Farid, Reza; Ansari, Elham; Kianifar, Hamid Reza; Jabbari Azad, Farahzad; Jafari, Seyed Ali; Purreza, Reza; Noorizadeh, Shadi

    2013-03-01

    Food Dependent Exercise-Induced Allergy is a rare condition. However, the occurrence of anaphylaxis is increasing especially in young people. The diagnosis of anaphylaxis is based on clinical criteria and can be supported by laboratory tests such as serum tryptase and positive skin test results for specific IgE to potential triggering allergens. Anaphylaxis prevention needs strict avoidance of confirmed relevant allergen. Food-exercise challenge test may be an acceptable method for diagnosis of Food Dependent Exercise-Induced Allergy and dietary elimination of food is recommended to manage it. In this study, a 32 year-old woman visited the allergy clinic with a history of several episodes of hives since 11 years ago and 3 life-threatening attacks of anaphylaxis during the previous 6 months. The onsets of majority of these attacks were due to physical activity after breakfast. On Blood RAST test, the panel of common food Allergens was used and she had positive test only to wheat flour. On skin prick tests for common food allergens she showed a 6 millimeter wheal with 14 mm flare to Wheat Extract. The rest of allergens were negative.The patient was diagnosed as wheat-dependent exercise-induced, and all foods containing wheat were omitted from her diet. In this report we emphasized on the importance of careful history taking in anaphylaxis diagnosis. PMID:23454785

  5. Primary renal magnesium wasting: an unusual clinical picture of exercise-induced symptoms.

    PubMed

    Stark, Christopher M; Nylund, Cade M; Gorman, Gregory H; Lechner, Brent L

    2016-04-01

    Magnesium is one of the most abundant cations in the human body and plays a key role as a metabolic enzyme cofactor and regulatory ion for neurons and cardiomyocytes. Hypomagnesemia due to isolated primary renal magnesium wasting is a rare clinical condition typically associated with neurological hyperexcitability. Exercise-related gastrointestinal symptoms are caused by ischemic, mechanical, or neurohormonal changes. The role of hypomagnesemia in gastrointestinal symptoms is not well understood. We present a case of a 15-year-old male who presented with exercise-induced abdominal pain, nausea, and vomiting, who was found to have profound hypomagnesemia and inappropriately elevated fractional excretion of magnesium (FEMg). Testing for multiple intrinsic and extrinsic etiologies of renal magnesium wasting was inconclusive. He was diagnosed with primary renal magnesium wasting and his symptoms resolved acutely with intravenous magnesium sulfate and with long-term oral magnesium chloride. Primary renal magnesium wasting is a rare clinical entity that can cause extreme hypomagnesemia. It has not been associated previously with exercise-induced gastrointestinal symptoms. The effects of hypomagnesemia on the human gastrointestinal tract are not well established. This case offers unique insights into the importance of magnesium homeostasis in the gastrointestinal tract. Exercise-induced splanchnic hypoperfusion may contribute to gastrointestinal symptoms observed in this chronically hypomagnesemic patient. PMID:27117800

  6. Attenuation of eccentric exercise-induced muscle damage conferred by maximal isometric contractions: a mini review

    PubMed Central

    Lima, Leonardo C. R.; Denadai, Benedito S.

    2015-01-01

    Although, beneficial in determined contexts, eccentric exercise-induced muscle damage (EIMD) might be unwanted during training regimens, competitions and daily activities. There are a vast number of studies investigating strategies to attenuate EIMD response after damaging exercise bouts. Many of them consist of performing exercises that induce EIMD, consuming supplements or using equipment that are not accessible for most people. It appears that performing maximal isometric contractions (ISOs) 2–4 days prior to damaging bouts promotes significant attenuation of EIMD symptoms that are not related to muscle function. It has been shown that the volume of ISOs, muscle length in which they are performed, and interval between them and the damaging bout influence the magnitude of this protection. In addition, it appears that this protection is not long-lived, lasting no longer than 4 days. Although no particular mechanisms for these adaptations were identified, professionals should consider applying this non-damaging stimulus before submitting their patients to unaccustomed exercised. However, it seems not to be the best option for athletes or relatively trained individuals. Future, studies should focus on establishing if ISOs protect other populations (i.e., trained individuals) or muscle groups (i.e., knee extensors) against EIMD, as well as investigate different mechanisms for ISO-induced protection. PMID:26578972

  7. FSTL1 as a Potential Mediator of Exercise-Induced Cardioprotection in Post-Myocardial Infarction Rats.

    PubMed

    Xi, Yue; Gong, Da-Wei; Tian, Zhenjun

    2016-01-01

    Exercise training has been reported to ameliorate heart dysfunction in both humans and animals after myocardial infarction (MI), but the underlying mechanisms are poorly understood. Follistatin-like1 (FSTL1) is a cardioprotective factor against ischemic injury and is induced in cardiomyocytes and skeletal muscle in ischemic and hypoxic conditions. To test the hypothesis that FSTL1 may be a molecular link between exercise and improved heart function post MI, we subjected MI-rats, induced by left coronary artery ligation, to two modes of exercise: intermittent aerobic exercise (IAE) or mechanical vibration training (MVT), for four weeks and examined the relevance of FSTL1 to exercise-mediated cardiac effects. Exercise improved the functional performance, reduced fibrosis of MI-hearts and induced FSTL1 expression, the TGFβ-Smad2/3 signaling and angiogenesis in myocardium. In gastrocnemius, exercise increased the cross-sectional area of myocytes and FSTL1 expression. Importantly, exercise increased circulating FSTL1 levels, which were positively correlated with the skeletal muscle FSTL1 expression and negatively correlated with heart fibrosis. Overall, the IAE was more effective than that of MVT in cardioprotection. Finally, exogenous FSTL1 administration directly improved angiogenesis as well as functionality of post-MI hearts. Taken together, we have demonstrated that FSTL1 is a potential mediator of exercise-induced cardioprotection in post-MI rats. PMID:27561749

  8. FSTL1 as a Potential Mediator of Exercise-Induced Cardioprotection in Post-Myocardial Infarction Rats

    PubMed Central

    Xi, Yue; Gong, Da-Wei; Tian, Zhenjun

    2016-01-01

    Exercise training has been reported to ameliorate heart dysfunction in both humans and animals after myocardial infarction (MI), but the underlying mechanisms are poorly understood. Follistatin-like1 (FSTL1) is a cardioprotective factor against ischemic injury and is induced in cardiomyocytes and skeletal muscle in ischemic and hypoxic conditions. To test the hypothesis that FSTL1 may be a molecular link between exercise and improved heart function post MI, we subjected MI-rats, induced by left coronary artery ligation, to two modes of exercise: intermittent aerobic exercise (IAE) or mechanical vibration training (MVT), for four weeks and examined the relevance of FSTL1 to exercise-mediated cardiac effects. Exercise improved the functional performance, reduced fibrosis of MI-hearts and induced FSTL1 expression, the TGFβ-Smad2/3 signaling and angiogenesis in myocardium. In gastrocnemius, exercise increased the cross-sectional area of myocytes and FSTL1 expression. Importantly, exercise increased circulating FSTL1 levels, which were positively correlated with the skeletal muscle FSTL1 expression and negatively correlated with heart fibrosis. Overall, the IAE was more effective than that of MVT in cardioprotection. Finally, exogenous FSTL1 administration directly improved angiogenesis as well as functionality of post-MI hearts. Taken together, we have demonstrated that FSTL1 is a potential mediator of exercise-induced cardioprotection in post-MI rats. PMID:27561749

  9. Single bout of running exercise changes LC3-II expression in rat cardiac muscle.

    PubMed

    Ogura, Yuji; Iemitsu, Motoyuki; Naito, Hisashi; Kakigi, Ryo; Kakehashi, Chiaki; Maeda, Seiji; Akema, Tatsuo

    2011-11-01

    Macroautophagy (autophagy) is an intracellular catalytic process. We examined the effect of running exercise, which stimulates cardiac work physiologically, on the expression of microtubule-associated protein 1 light chain 3 (LC3)-II, an indicator of autophagy, as well as some autophagy-related proteins in rat cardiac muscle. The left ventricles were taken from rats immediately (0 h), and at 0.5h, 1h or 3h after a single bout of running exercise on a treadmill for 30 min and also from rats in a rest condition. In these samples, we evaluated the level of LC3-II and p62, and the phosphorylation level of mammalian target of rapamycin (mTOR), Akt and AMP-activated protein kinase alpha (AMPKα) by Western blotting. The exercise produced a biphasic change in LC3-II, with an initial decrease observed immediately after the exercise and a subsequent increase 1h thereafter. LC3-II then returned to the rest level at 3h after the exercise. A negative correlation was found between the LC3-II expression and mTOR phosphorylation, which plays a role in inhibiting autophagy. The exercise increased phosphorylation of AMPKα, which stimulates autophagy via suppression of mTOR phosphorylation, immediately after exercise. The level of p62 and phosphorylated Akt was not altered significantly by the exercise. These results suggest for the first time that a single bout of running exercise induces a biphasic change in autophagy in the cardiac muscle. The exercise-induced change in autophagy might be partially mediated by mTOR in the cardiac muscle. PMID:22005460

  10. Irisin - a myth rather than an exercise-inducible myokine.

    PubMed

    Albrecht, Elke; Norheim, Frode; Thiede, Bernd; Holen, Torgeir; Ohashi, Tomoo; Schering, Lisa; Lee, Sindre; Brenmoehl, Julia; Thomas, Selina; Drevon, Christian A; Erickson, Harold P; Maak, Steffen

    2015-01-01

    The myokine irisin is supposed to be cleaved from a transmembrane precursor, FNDC5 (fibronectin type III domain containing 5), and to mediate beneficial effects of exercise on human metabolism. However, evidence for irisin circulating in blood is largely based on commercial ELISA kits which are based on polyclonal antibodies (pAbs) not previously tested for cross-reacting serum proteins. We have analyzed four commercial pAbs by Western blotting, which revealed prominent cross-reactivity with non-specific proteins in human and animal sera. Using recombinant glycosylated and non-glycosylated irisin as positive controls, we found no immune-reactive bands of the expected size in any biological samples. A FNDC5 signature was identified at ~20 kDa by mass spectrometry in human serum but was not detected by the commercial pAbs tested. Our results call into question all previous data obtained with commercial ELISA kits for irisin, and provide evidence against a physiological role for irisin in humans and other species. PMID:25749243

  11. Enhanced exercise-induced plasma cytokine response and oxidative stress in COPD patients depend on blood oxygenation.

    PubMed

    Jammes, Yves; Steinberg, Jean Guillaume; Ba, Abdoulaye; Delliaux, Stéphane; Brégeon, Fabienne

    2008-05-01

    In healthy subjects, hypoxemia and exercise represent independent stressors promoting the exercise-induced cytokine response and oxidative stress. We hypothesized that hypoxemia in patients with chronic obstructive pulmonary disease (COPD) may affect the cytokine production and/or the changes in oxidant-antioxidant status in response to maximal exercise. Exercise-induced changes in PaO2 allowed to transiently increase or decrease baseline hypoxemia and to point out its specific action on muscle metabolism. COPD patients with severe to moderate hypoxemia (56 < PaO2 < 72 mmHg) performed an incremental cycling exercise until volitional exhaustion. Two cytokines [interleukin (IL)-6 and tumour necrosis factor (TNF)-alpha] and three blood indices of oxidative stress [plasma thiobarbituric acid reactive substances (TBARS) and two antioxidants, reduced erythrocyte glutathione (GSH), and reduced plasma ascorbic acid, RAA] were measured at rest, then during and after exercise. The changes in the cytokine levels and oxidant-antioxidant status were analysed in relation with the baseline PaO2 and its exercise-induced variations. Data were compared with those obtained in an age- and body mass index-matched group of healthy subjects. Compared with healthy subjects, COPD patients presented a marked accentuation of exercise-induced increase in IL-6 level and earlier changes in their oxidant-antioxidant status. Resting levels of IL-6 and TNF-alpha and exercise-induced peak variations of TBARS, IL-6 and TNF-alpha were negatively correlated with the baseline PaO2. In COPD patients, the peak increases in IL-6 and TBARS were attenuated when exercise hyperventilation reduced the baseline hypoxemia. Our study indicates that the PaO2 level affects both the exercise-induced oxidative stress and cytokine response in hypoxemic COPD patients. PMID:18312445

  12. Statin-induced Myopathy in Skeletal Muscle: the Role of Exercise.

    PubMed

    Kwak, Hyo-Bum

    2014-09-01

    Statins are widely used drugs to lower cholesterol levels and to reduce the risk of cardiovascular disease. However, it has been reported that statins are associated with adverse side effects of skeletal myopathy. Statin treatment can impair mitochondrial function and induce apoptosis in skeletal muscle in both human and animal models. Ubiquinone plays an essential role in transferring electrons in the mitochondrial electron transfer chain for oxidative phosphorylation. However, statin treatment reduces ubiquinone levels in the cholesterol synthesis pathway, which may be associated with mitochondrial dysfunction. In addition, reactive oxygen species (ROS) production and apoptosis induced by statins may provide cellular and molecular mechanisms in skeletal myopathy. Exercise is the most effective therapy to prevent metabolic and cardiovascular diseases. However, whether exercise provides a benefit to or exacerbation of statin-induced myopathy in skeletal muscle remains poorly investigated. This review will briefly provide a comprehensive summary regarding the effects of statins on skeletal myopathy, and discuss the potential mechanisms of statin-induced myopathy and the role of exercise in statin-induced myopathy in skeletal muscle. PMID:26064857

  13. Statin-induced Myopathy in Skeletal Muscle: the Role of Exercise

    PubMed Central

    Kwak, Hyo-Bum

    2014-01-01

    Statins are widely used drugs to lower cholesterol levels and to reduce the risk of cardiovascular disease. However, it has been reported that statins are associated with adverse side effects of skeletal myopathy. Statin treatment can impair mitochondrial function and induce apoptosis in skeletal muscle in both human and animal models. Ubiquinone plays an essential role in transferring electrons in the mitochondrial electron transfer chain for oxidative phosphorylation. However, statin treatment reduces ubiquinone levels in the cholesterol synthesis pathway, which may be associated with mitochondrial dysfunction. In addition, reactive oxygen species (ROS) production and apoptosis induced by statins may provide cellular and molecular mechanisms in skeletal myopathy. Exercise is the most effective therapy to prevent metabolic and cardiovascular diseases. However, whether exercise provides a benefit to or exacerbation of statin-induced myopathy in skeletal muscle remains poorly investigated. This review will briefly provide a comprehensive summary regarding the effects of statins on skeletal myopathy, and discuss the potential mechanisms of statin-induced myopathy and the role of exercise in statin-induced myopathy in skeletal muscle. PMID:26064857

  14. Central and peripheral cardiovascular responses to electrically induced and voluntary leg exercise

    NASA Technical Reports Server (NTRS)

    Saltin, B.; Strange, S.; Bangsbo, J.; Kim, C. K.; Duvoisin, M.; Hargens, A.; Gollnick, P. D.

    1990-01-01

    With long missions in space countermeasures have to be used to secure safe operations in space and a safe return to Earth. Exercises of various forms have been used, but the question has arisen whether electrically induced contractions of muscle especially sensitive to weightlessness and crucial for man's performance would aid in maintaining their optimal function. The physiological responses both to short term and prolonged dynamic exercise performed either voluntarily or induced by electrical stimulation were considered. The local and systemic circulatory responses were similar for the voluntary and electrically induced contractions. The metabolic response was slightly more pronounced with electrical stimulation. This could be a reflection of not only slow twitch (type 1) but also fast twitch (type 2) fibers being recruited when the contractions were induced electrically. Intramuscular pressure recordings indicated that the dominant fraction of the muscle group was engaged regardless of mode of activation. Some 70 percent of the short term peak voluntary exercise capacity could be attained with electrical stimulation. Thus, electrically induced contractions of specific muscle groups should indeed be considered as an efficient countermeasure.

  15. Syndecan-4 Signaling Is Required for Exercise-Induced Cardiac Hypertrophy

    PubMed Central

    Xie, Jun; He, Guixin; Chen, Qinhua; Sun, Jiayin; Dai, Qin; Lu, Jianrong; Li, Guannan; Wu, Han; Li, Ran; Chen, Jianzhou; Xu, Wei; Xu, Biao

    2016-01-01

    Cardiac hypertrophy can be broadly classified as either physiological or pathological. Physiological stimuli such as exercise cause adaptive cardiac hypertrophy and normal heart function. Pathological stimuli including hypertension and aortic valvular stenosis cause maladaptive cardiac remodeling and ultimately heart failure. Syndecan-4 (synd4) is a transmembrane proteoglycan identified as being involved in cardiac adaptation after injury, but whether it takes part in physiological cardiac hypertrophy is unclear. We observed upregulation of synd4 in exercise-induced hypertrophic myocardium. To evaluate the role of synd4 in the physiological form of cardiac hypertrophy, mice lacking synd4 (synd4–/–) were exercised by swimming for 4 wks. Ultrasonic cardiogram (UCG) and histological analysis revealed that swimming induced the hypertrophic phenotype but was blunted in synd4–/– compared with wild-type (WT) mice. The swimming-induced activation of Akt, a key molecule in physiological hypertrophy was also more decreased than in WT controls. In cultured cardiomyocytes, synd4 overexpression could induce cell enlargement, protein synthesis and distinct physiological molecular alternation. Akt activation also was observed in synd4-overexpressed cardiomyocytes. Furthermore, inhibition of protein kinase C (PKC) prevented the synd4-induced hypertrophic phenotype and Akt phosphorylation. This study identified an essential role of synd4 in mediation of physiological cardiac hypertrophy. PMID:26835698

  16. [Exercise training in hypoxia prevents hypoxia induced mitochondrial DNA oxidative damage in skeletal muscle].

    PubMed

    Bo, Hai; Li, Ling; Duan, Fu-Qiang; Zhu, Jiang

    2014-10-25

    This study was undertaken to investigate the effect of exercise training on mitochondrial DNA (mtDNA) oxidative damage and 8-oxoguanine DNA glycosylase-1 (OGG1) expression in skeletal muscle of rats under continuous exposure to hypoxia. Male Sprague-Dawley rats were randomly divided into 4 groups (n = 8): normoxia control group (NC), normoxia training group (NT), hypoxia control group (HC), and hypoxia training group (HT). The hypoxia-treated animals were housed in normobaric hypoxic tent containing 11.3% oxygen for consecutive 4 weeks. The exercise-trained animals were exercised on a motor-driven rodent treadmill at a speed of 15 m/min, 5% grade for 60 min/day, 5 days per week for 4 weeks. The results showed that, compared with NC group, hypoxia attenuated complex I, II, IV and ATP synthase activities of the electron transport chain, and the level of mitochondrial membrane potential in HC group (P < 0.05 or P < 0.01). Moreover, hypoxia decreased mitochondrial OGG1, MnSOD, and GPx activities (P < 0.05 or P < 0.01), whereas elevated reactive oxygen species (ROS) generation and the level of 8-oxo-deoxyguanosine (8-oxodG) in mtDNA (P < 0.01). Furthermore, hypoxia attenuated muscle and mitochondrial [NAD⁺]/ [NADH] ratio, and SIRT3 protein expression (P < 0.05 or P < 0.01). Compared with HC group, exercise training in hypoxia elevated complex I, II, IV and ATP synthase activities, and the level of mitochondrial membrane potential in HT group (P < 0.05 or P < 0.01). Moreover, exercise training in hypoxia increased MnSOD and GPx activities and mitochondrial OGG1 level (P < 0.01), whereas decreased ROS generation and the level of 8-oxodG in mtDNA (P < 0.01). Furthermore, exercise training in hypoxia increased muscle and mitochondrial [NAD⁺]/[NADH] ratio, as well as SIRT3 protein expression (P < 0.05 or P < 0.01). These findings suggest that exercise training in hypoxia can decrease hypoxia-induced mtDNA oxidative damage in the skeletal muscle through up

  17. Effect of exercise-induced fatigue on postural control of the knee.

    PubMed

    Hassanlouei, H; Arendt-Nielsen, L; Kersting, U G; Falla, D

    2012-06-01

    Muscle fatigue is associated with reduced power output and work capacity of the skeletal muscle. Fatigue-induced impairments in muscle function are believed to be a potential cause of increased injury rates during the latter stages of athletic competition and often occur during unexpected perturbations. However the effect of fatigue on functionally relevant, full body destabilizing perturbations has not been investigated. This study examines the effect of muscle fatigue on the activation of the quadriceps and hamstrings to fast, full body perturbations evoked by a moveable platform. Surface electromyographic (EMG) signals were recorded from the knee extensor (vastus medialis, rectus femoris, and vastus lateralis) and flexor muscles (biceps femoris and semitendinosus) of the right leg in nine healthy men during full body perturbations performed at baseline and immediately following high intensity exercise performed on a bicycle ergometer. In each condition, participants stood on a moveable platform during which 16 randomized postural perturbations (eight repetitions of two perturbation types: 8 cm forward slides, 8 cm backward slides) with varying inter-perturbation time intervals were performed over a period of 2-3 min. Maximal voluntary knee extension force was measured before and after the high intensity exercise protocol to confirm the presence of fatigue. Immediately after exercise, the maximal force decreased by 63% and 66% for knee extensors and flexors, respectively (P<0.0001). During the post-exercise postural perturbations, the EMG average rectified value (ARV) was significantly lower than the baseline condition for both the knee extensors (average across all muscles; baseline: 19.7±25.4μV, post exercise: 16.2±19.4 μV) and flexors (baseline: 24.3±20.9 μV, post exercise: 13.8±11.0 μV) (both P<0.05). Moreover the EMG onset was significantly delayed for both the knee extensors (baseline: 132.7±32.9 ms, post exercise: 170.8±22.9 ms) and flexors

  18. Prevention of exercised induced cardiomyopathy following Pip-PMO treatment in dystrophic mdx mice.

    PubMed

    Betts, Corinne A; Saleh, Amer F; Carr, Carolyn A; Hammond, Suzan M; Coenen-Stass, Anna M L; Godfrey, Caroline; McClorey, Graham; Varela, Miguel A; Roberts, Thomas C; Clarke, Kieran; Gait, Michael J; Wood, Matthew J A

    2015-01-01

    Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disorder caused by mutations in the Dmd gene. In addition to skeletal muscle wasting, DMD patients develop cardiomyopathy, which significantly contributes to mortality. Antisense oligonucleotides (AOs) are a promising DMD therapy, restoring functional dystrophin protein by exon skipping. However, a major limitation with current AOs is the absence of dystrophin correction in heart. Pip peptide-AOs demonstrate high activity in cardiac muscle. To determine their therapeutic value, dystrophic mdx mice were subject to forced exercise to model the DMD cardiac phenotype. Repeated peptide-AO treatments resulted in high levels of cardiac dystrophin protein, which prevented the exercised induced progression of cardiomyopathy, normalising heart size as well as stabilising other cardiac parameters. Treated mice also exhibited significantly reduced cardiac fibrosis and improved sarcolemmal integrity. This work demonstrates that high levels of cardiac dystrophin restored by Pip peptide-AOs prevents further deterioration of cardiomyopathy and pathology following exercise in dystrophic DMD mice. PMID:25758104

  19. Prevention of exercised induced cardiomyopathy following Pip-PMO treatment in dystrophic mdx mice

    PubMed Central

    Betts, Corinne A.; Saleh, Amer F.; Carr, Carolyn A.; Hammond, Suzan M.; Coenen-Stass, Anna M. L.; Godfrey, Caroline; McClorey, Graham; Varela, Miguel A.; Roberts, Thomas C.; Clarke, Kieran; Gait, Michael J.; Wood, Matthew J. A.

    2015-01-01

    Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disorder caused by mutations in the Dmd gene. In addition to skeletal muscle wasting, DMD patients develop cardiomyopathy, which significantly contributes to mortality. Antisense oligonucleotides (AOs) are a promising DMD therapy, restoring functional dystrophin protein by exon skipping. However, a major limitation with current AOs is the absence of dystrophin correction in heart. Pip peptide-AOs demonstrate high activity in cardiac muscle. To determine their therapeutic value, dystrophic mdx mice were subject to forced exercise to model the DMD cardiac phenotype. Repeated peptide-AO treatments resulted in high levels of cardiac dystrophin protein, which prevented the exercised induced progression of cardiomyopathy, normalising heart size as well as stabilising other cardiac parameters. Treated mice also exhibited significantly reduced cardiac fibrosis and improved sarcolemmal integrity. This work demonstrates that high levels of cardiac dystrophin restored by Pip peptide-AOs prevents further deterioration of cardiomyopathy and pathology following exercise in dystrophic DMD mice. PMID:25758104

  20. Exercise-induced pulmonary hemorrhage in a nonathlete: case report and review of physiology.

    PubMed

    Diwakar, Amit; Schmidt, Gregory A

    2014-04-01

    The integrity of the pulmonary blood-gas barrier is vulnerable to intense exercise in elite athletes, similar to the phenomenon of exercise-induced pulmonary hemorrhage in thoroughbred racehorses. A 50-year-old previously healthy man presented with acute onset shortness of breath, dry cough, and hypoxemia after engaging in an extremely vigorous game of handball. CT scan of the chest showed diffuse patchy air-space disease. Bronchoalveolar lavage revealed diffuse alveolar hemorrhage. Infectious etiologies and bleeding diatheses were excluded by laboratory testing. Serological tests for ANCA-associated vasculitis, lupus, and Goodpasture's disease also were negative. A transthoracic echocardiogram was normal. The patient recovered completely on supportive therapy in less than 72 h. This case demonstrates strenuous exercise as a cause of diffuse alveolar hemorrhage in a previously healthy male with no apparent underlying cardiopulmonary disease. PMID:24532148

  1. Biphasic effect of Solanum nigrum fruit aqueous extract on vascular mesenteric beds in non-diabetic and streptozotocin-induced diabetic rats

    PubMed Central

    Sohrabipour, Shahla; Kharazmi, Fatemah; Soltani, Nepton; Kamalinejad, Mohammad

    2014-01-01

    Background: In Asia, Solanum nigrum fruit is traditionally used to manage, control, and treat diabetes. Objective: This study was carried out to investigate the endothelium and nitric oxide roles in Solanum nigrum-induced vasorelaxation in non-diabetic and diabetic rat vessels. Materials and Methods: Diabetes was induced by a single i.p. injection of streptozotocin. Eight weeks later, superior mesenteric arteries of non-diabetic and diabetic groups were isolated and perfused according to the McGregor method. Solanum nigrum fruit extract (SNE) at concentrations of 0.00001 to 0.6 mg/ml was added to the medium and perfusion pressure was recorded. Results: Baseline perfusion pressure of diabetic group was significantly higher than non-diabetic rats in both intact and denuded endothelium. The low concentrations of SNE have vasodilatory effect in the diabetic and non-diabetic, but high concentrations of SNE produce initial significant contractions, followed by secondary relaxations in normal and diabetic rats. We observed vasorelaxation at low and high concentrations of SNE in both diabetic and non-diabetic groups after endothelium denudation. SNE-induced vasorelaxation in diabetic group is mediated by both endothelium and smooth muscle, but the relaxatory effect of SNE in non-diabetic group is not mediated by endothelium, and SNE has direct action on the smooth muscle. Conclusion: Although the part of SNE-induced relaxation in diabetic vessel was mediated by endothelium, nitric oxide didn’t play any role in this action, and maybe we can use SNE in the management of diabetes vessel complications in future. PMID:24761120

  2. Concentrically trained cyclists are not more susceptible to eccentric exercise-induced muscle damage than are stretch-shortening exercise-trained runners.

    PubMed

    Snieckus, Audrius; Kamandulis, Sigitas; Venckūnas, Tomas; Brazaitis, Marius; Volungevičius, Gintautas; Skurvydas, Albertas

    2013-03-01

    Here, we test the hypothesis that continuous concentric exercise training renders skeletal muscles more susceptible to damage in response to eccentric exercise. Elite road cyclists (CYC; n = 10, training experience 8.1 ± 2.0 years, age 22.9 ± 3.7 years), long-distance runners (LDR; n = 10, 9.9 ± 2.3 years, 24.4 ± 2.5 years), and healthy untrained (UT) men (n = 10; 22.4 ± 1.7 years) performed 100 submaximal eccentric contractions at constant angular velocity of 60° s(-1). Concentric isokinetic peak torque, isometric maximal voluntary contraction (MVC), and electrically induced knee extension torque were measured at baseline and immediately and 48 h after an eccentric exercise bout. Muscle soreness was assessed and plasma creatine kinase (CK) activity was measured at baseline and 48 h after exercise. Voluntary and electrically stimulated knee extension torque reduction were significantly greater (p < 0.05) in UT than in LDR and CYC. Immediately and 48 h after exercise, MVC decreased by 32 % and 20 % in UT, 20 % and 5 % in LDR, and 25 % and 6 % in CYC. Electrically induced 20 Hz torque decreased at the same times by 61 and 29 % in UT, 40 and 17 % in LDR, and 26 and 14 % in CYC. Muscle soreness and plasma CK activity 48 h after exercise did not differ significantly between athletes and UT subjects. In conclusion, even though elite endurance athletes are more resistant to eccentric exercise-induced muscle damage than are UT people, stretch-shortening exercise-trained LDR have no advantage over concentrically trained CYC. PMID:22886189

  3. Endurance training improves the resistance of rat diaphragm to exercise-induced oxidative stress.

    PubMed

    Oh-ishi, S; Kizaki, T; Ookawara, T; Sakurai, T; Izawa, T; Nagata, N; Ohno, H

    1997-11-01

    The current study was designed to test the hypothesis that endurance training improves the ability of the diaphragm muscle to resist exercise-induced oxidative stress. Twenty-eight male Wistar rats were assigned to either untrained or trained groups. Trained rats were treadmill-trained for 9 wk. Each group was subdivided into acutely exercised or nonexercised groups. Diaphragm muscle from each rat was analyzed to determine the levels of certain antioxidant enzymes: Mn-superoxide dismutase (Mn-SOD), Cu,Zn-superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase, and catalase. In addition, interleukin-1 and myeloperoxidase levels were determined. Endurance training upregulated all of the antioxidant enzymes. Conversely, acute exercise increased glutathione peroxidase and catalase in untrained rats, while it had no overt effect on any antioxidant enzymes in trained rats. Both Mn-SOD and Cu,Zn-SOD contents and activities were increased with endurance training. However, the mRNA expressions of both forms of SOD did not show any significant change with endurance training. Acute exercise also increased the levels of interleukin-1 and myeloperoxidase in untrained rats but not in trained rats. Moreover, acute exercise significantly increased the ability of neutrophils to produce superoxide, especially in untrained rats. The results from this study demonstrate that endurance training can upregulate certain antioxidant enzyme activities in rat diaphragm muscle, indicating the potential for improvement of the resistance to intracellular reactive oxygen species. The results of this study also suggest that acute exercise may cause oxidative damage in rat diaphragm through the activation of the inflammatory pathway and that endurance training may minimize such an extracellular oxidative stress by acute exercise. PMID:9372679

  4. Contribution of diaphragmatic power output to exercise-induced diaphragm fatigue.

    PubMed

    Babcock, M A; Pegelow, D F; McClaran, S R; Suman, O E; Dempsey, J A

    1995-05-01

    In nine normal humans we compared the effects on diaphragm fatigue of whole body exercise to exhaustion (86-93% of maximal O2 uptake for 13.2 +/- 2.0 min) to voluntary increases in the tidal integral of transdiaphragmatic pressure (integral of Pdi) while at rest at the same magnitude and frequency and for the same duration as those during exercise. After the endurance exercise, we found a consistent and significant fall (-26 +/- 2.9%, range -19.2 to -41.0%) in the Pdi response to supramaximal bilateral phrenic nerve stimulation at all stimulation frequencies (1, 10, and 20 Hz). Integral of Pdi.fB (where fB is breathing frequency) achieved during exercise averaged 509 +/- 81.0 cmH2O/min (range 304.0-957.0 cmH2O/min). At rest, voluntary production of integral of Pdi.fB, which was < 550-600 cmH2O/min (approximately 4 times the resting eupenic integral of Pdi.fB or 60-70% of Pdi capacity), did not result in significant diaphragmatic fatigue, whereas sustained voluntary production of integral of Pdi.fB in excess of these threshold values usually did result in significant fatigue. Thus, with few exceptions (5 of 23 tests) the ventilatory requirements of whole body endurance exercise demanded a level of integral of Pdi.fB that, by itself, was not fatiguing. The rested first dorsal interosseous muscle showed no fatigue in response to supramaximal ulnar nerve stimulation after whole body exercise. We postulate that the effects of locomotor muscle activity, such as competition for blood flow distribution and/or extracellular fluid acidosis, in conjunction with a contracting diaphragm account for most of the exercise-induced diaphragm fatigue. PMID:7649904

  5. How accurate is the diagnosis of exercise induced asthma among Vancouver schoolchildren?

    PubMed Central

    Seear, M; Wensley, D; West, N

    2005-01-01

    Background: Limited access to exercise testing facilities means that the diagnosis of exercise induced asthma (EIA) is mainly based on self-reported respiratory symptoms. This is open to error since the correlation between exercise related symptoms and subsequent exercise testing has been shown to be poor. Aim: To study the accuracy of clinically diagnosed EIA among Vancouver schoolchildren. Methods: Fifty two children referred for investigation of poorly controlled EIA were studied. Following a careful history and physical examination, children performed pulmonary function tests before, then 5 and 15 minutes after a standardised treadmill exercise test. Based on overall assessment, a diagnostic explanation for each child's respiratory complaints was provided as far as possible. Results: Only eight children (15.4%) fulfilled diagnostic criteria for EIA (fall in FEV1 ⩾10%). Of the remainder: 12 (23.1%) were unfit, 14 (26.9%) had vocal cord dysfunction/sigh dyspnoea, 7 (13.5%) had a habit cough, and 11 (21.1%) had no abnormalities on clinical or laboratory testing, so were given no diagnosis. Initial reported symptoms of wheeze or cough often changed significantly following a careful history, particularly among the eight elite athletes. The final complaint was sometimes not respiratory, and, in a few cases, was not even associated with exercise. Conclusions: The clinical diagnosis of EIA is inaccurate among Vancouver schoolchildren, principally due to the unreliability of their initial exercise related complaints. Symptom exaggeration, familiarity with medical jargon, and psychogenic complaints are all common. A careful history is essential in this population before basing any diagnosis on self-reported respiratory symptoms. PMID:15855180

  6. Beneficial effects of previous exercise training on renal changes in streptozotocin-induced diabetic female rats.

    PubMed

    Amaral, Liliany S de Brito; Silva, Fernanda A; Correia, Vicente B; Andrade, Clara Ef; Dutra, Bárbara A; Oliveira, Márcio V; Magalhães, Amélia Cm de; Volpini, Rildo A; Seguro, Antonio C; Coimbra, Terezila M; Soares, Telma de J

    2016-02-01

    This study evaluated the effects of aerobic exercise performed both previously and after the induction of diabetes mellitus on changes of renal function and structure in streptozotocin-induced diabetic rats. Female wistar rats were divided into five groups: sedentary control (C + Se); trained control (C + Ex); sedentary diabetic (D + Se); trained diabetic (D + Ex) and previously trained diabetic (D + PEx). The previous exercise consisted of treadmill running for four weeks before the induction of diabetes mellitus. After induction of diabetes mellitus with streptozotocin, the D + PEx, D + Ex and C + Ex groups were submitted to eight weeks of aerobic exercise. At the end of the training protocol, we evaluate the serum glucose, insulin and 17β-estradiol levels, renal function and structure, proteinuria, and fibronectin, collagen IV and transforming growth factor beta 1 (TGF-β1) renal expressions. Induction of diabetes mellitus reduced the insulin and did not alter 17β-estradiol levels, and exercise did not affect any of these parameters. Previous exercise training attenuated the loss of body weight, the blood glucose, the increase of glomerular filtration rate and prevented the proteinuria in the D + PEx group compared to D + Se group. Previous exercise also reduced glomerular hypertrophy, tubular and glomerular injury, as well as the expressions of fibronectin and collagen IV. These expressions were associated with reduced expression of TGF-β1. In conclusion, our study shows that regular aerobic exercise especially performed previously to induction of diabetes mellitus improved metabolic control and has renoprotective action on the diabetic kidney. PMID:26490345

  7. Chronic endurance exercise training offsets the age-related attenuation in contraction-induced rapid vasodilation.

    PubMed

    Hughes, William E; Ueda, Kenichi; Casey, Darren P

    2016-06-01

    Aging is associated with attenuated contraction-induced rapid onset vasodilation (ROV). We sought to examine whether chronic exercise training would improve ROV in older adults. Additionally, we examined whether a relationship between cardiorespiratory fitness and ROV exists in young and older adults. Chronically exercise-trained older adults (n = 16; 66 ± 2 yr, mean ± SE) performed single muscle contractions in the forearm and leg at various intensities. Brachial and femoral artery diameter and blood velocity were measured using Doppler ultrasound. Vascular conductance (VC) was calculated as the quotient of blood flow (ml/min) and mean arterial pressure (mmHg). These data were compared with our previously published work from an identical protocol in 16 older untrained (66 ± 1 yr, mean ± SE) and 14 young (23 ± 1 yr) adults. Peak (ΔVCpeak) and total vasodilator (VCtotal) responses were greater in trained compared with untrained older adults across leg exercise intensities (P < 0.05). There were no differences in responses between trained older and young adults in the arm or leg at any exercise intensity (P > 0.05). Comparison of ΔVCpeak in a subset of subjects at an absolute workload in the leg revealed that trained older adults exhibited augmented responses relative to untrained older adults. Exercise capacity (V̇o2 peak) was associated with ΔVCpeak and VCtotal across arm (r = 0.59-0.64) and leg exercise intensities (r = 0.55-0.68, P < 0.05) in older adults. Our data demonstrate that 1) chronic exercise training improves ROV in the arm and leg of trained older adults, such that age-related differences in ROV are abolished, and 2) VO2peak is associated with ΔVCpeak responses in both limbs of older adults. PMID:27032899

  8. Glycogen overload by postexercise insulin administration abolished the exercise-induced increase in GLUT4 protein.

    PubMed

    Chou, Chia-Hau; Tsai, Yin-Lan; Hou, Chien-Wen; Lee, Hsing-Hao; Chang, Wei-Hsiang; Lin, Tzi-Wen; Hsu, Tung-Hsiung; Huang, Yi-Jen; Kuo, Chia-Hua

    2005-12-01

    To elucidate the role of muscle glycogen storage on regulation of GLUT4 protein expression and whole-body glucose tolerance, muscle glycogen level was manipulated by exercise and insulin administration. Sixty Sprague-Dawley rats were evenly separated into three groups: control (CON), immediately after exercise (EX0), and 16 h after exercise (EX16). Rats from each group were further divided into two groups: saline- and insulin-injected. The 2-day exercise protocol consisted of 2 bouts of 3-h swimming with 45-min rest for each day, which effectively depleted glycogen in both red gastrocnemius (RG) and plantaris muscles. EX0 rats were sacrificed immediately after the last bout of exercise on second day. CON and EX16 rats were intubated with 1 g/kg glucose solution following exercise and recovery for 16 h before muscle tissue collection. Insulin (0.5 microU/kg) or saline was injected daily at the time when glucose was intubated. Insulin injection elevated muscle glycogen levels substantially in both muscles above saline-injected group at CON and EX16. With previous day insulin injection, EX0 preserved greater amount of postexercise glycogen above their saline-injected control. In the saline-injected rats, EX16 significantly increased GLUT4 protein level above CON, concurrent with muscle glycogen supercompensation. Insulin injection for EX16 rats significantly enhanced muscle glycogen level above their saline-injected control, but the increases in muscle GLUT4 protein and whole-body glucose tolerance were attenuated. In conclusion, the new finding of the study was that glycogen overload by postexercise insulin administration significantly abolished the exercise-induced increases in GLUT4 protein and glucose tolerance. PMID:16319996

  9. Congenital laryngomalacia is related to exercise-induced laryngeal obstruction in adolescence

    PubMed Central

    Hilland, Magnus; Røksund, Ola Drange; Sandvik, Lorentz; Haaland, Øystein; Aarstad, Hans Jørgen; Halvorsen, Thomas; Heimdal, John-Helge

    2016-01-01

    Objectives Congenital laryngomalacia (CLM) is the major cause of stridor in infants. Most cases are expected to resolve before 2 years of age, but long-term respiratory prospects are poorly described. We aimed to investigate if CLM was associated with altered laryngeal structure or function in later life. Methods Twenty of 23 (87%) infants hospitalised at Haukeland University Hospital during 1990–2000 for CLM without comorbidities and matched controls were assessed at mean age 13 years. Past and current respiratory morbidity was recorded in a questionnaire, and spirometry performed according to standard quality criteria. Laryngoscopy was performed at rest and continuously throughout a maximal treadmill exercise test (continuous laryngoscopy exercise test (CLE-test)), and scored and classified in a blinded fashion according to preset criteria. Results In the CLM group, laryngeal anatomy supporting CLM in infancy was described at rest in nine (45%) adolescents. Eleven (55%) reported breathing difficulties in relation to exercise, of whom 7 had similarities to CLM at rest and 10 had supraglottic obstruction during CLE-test. Overall, 6/20 had symptoms during exercise and similarities to CLM at rest and obstruction during CLE-test. In the control group, one adolescent reported breathing difficulty during exercise and two had laryngeal obstruction during CLE-test. The two groups differed significantly from each other regarding laryngoscopy scores, obtained at rest and during exercise (p=0.001 or less). Conclusions CLM had left footprints that increased the risk of later exercise-induced symptoms and laryngeal obstruction. The findings underline the heterogeneity of childhood respiratory disease and the importance of considering early life factors. PMID:26906070

  10. Exercise-induced protection against reperfusion arrhythmia involves stabilization of mitochondrial energetics.

    PubMed

    Alleman, Rick J; Tsang, Alvin M; Ryan, Terence E; Patteson, Daniel J; McClung, Joseph M; Spangenburg, Espen E; Shaikh, Saame Raza; Neufer, P Darrell; Brown, David A

    2016-05-15

    Mitochondria influence cardiac electrophysiology through energy- and redox-sensitive ion channels in the sarcolemma, with the collapse of energetics believed to be centrally involved in arrhythmogenesis. This study was conducted to determine if preservation of mitochondrial membrane potential (ΔΨm) contributes to the antiarrhythmic effect of exercise. We utilized perfused hearts, isolated myocytes, and isolated mitochondria exposed to metabolic challenge to determine the effects of exercise on cardiac mitochondria. Hearts from sedentary (Sed) and exercised (Ex; 10 days of treadmill running) Sprague-Dawley rats were perfused on a two-photon microscope stage for simultaneous measurement of ΔΨm and ECG. After ischemia-reperfusion, the collapse of ΔΨm was commensurate with the onset of arrhythmia. Exercise preserved ΔΨm and decreased the incidence of fibrillation/tachycardia (P < 0.05). Our findings in intact hearts were corroborated in isolated myocytes exposed to in vitro hypoxia-reoxygenation, with Ex rats demonstrating enhanced redox control and sustained ΔΨm during reoxygenation. Finally, we induced anoxia-reoxygenation in isolated mitochondria using high-resolution respirometry with simultaneous measurement of respiration and H2O2 Mitochondria from Ex rats sustained respiration with lower rates of H2O2 emission than Sed rats. Exercise helps sustain postischemic mitochondrial bioenergetics and redox homeostasis, which is associated with preserved ΔΨm and protection against reperfusion arrhythmia. The reduction of fatal ventricular arrhythmias through exercise-induced mitochondrial adaptations indicates that mitochondrial therapeutics may be an effective target for the treatment of heart disease. PMID:26945082

  11. Vitamin D2 Supplementation Amplifies Eccentric Exercise-Induced Muscle Damage in NASCAR Pit Crew Athletes

    PubMed Central

    Nieman, David C.; Gillitt, Nicholas D.; Shanely, R. Andrew; Dew, Dustin; Meaney, Mary Pat; Luo, Beibei

    2013-01-01

    This study determined if 6-weeks vitamin D2 supplementation (vitD2, 3800 IU/day) had an influence on muscle function, eccentric exercise-induced muscle damage (EIMD), and delayed onset of muscle soreness (DOMS) in National Association for Stock Car Auto Racing (NASCAR) NASCAR pit crew athletes. Subjects were randomized to vitD2 (n = 13) and placebo (n = 15), and ingested supplements (double-blind) for six weeks. Blood samples were collected and muscle function tests conducted pre- and post-study (leg-back and hand grip dynamometer strength tests, body weight bench press to exhaustion, vertical jump, 30-s Wingate test). Post-study, subjects engaged in 90 min eccentric-based exercise, with blood samples and DOMS ratings obtained immediately after and 1- and 2-days post-exercise. Six weeks vitD2 increased serum 25(OH)D2 456% and decreased 25(OH)D3 21% versus placebo (p < 0.001, p = 0.036, respectively), with no influence on muscle function test scores. The post-study eccentric exercise bout induced EIMD and DOMS, with higher muscle damage biomarkers measured in vitD2 compared to placebo (myoglobin 252%, 122% increase, respectively, p = 0.001; creatine phosphokinase 24 h post-exercise, 169%, 32%, p < 0.001), with no differences for DOMS. In summary, 6-weeks vitD2 (3800 IU/day) significantly increased 25(OH)D2 and decreased 25(OH)D3, had no effect on muscle function tests, and amplified muscle damage markers in NASCAR pit crew athletes following eccentric exercise. PMID:24362707

  12. Epigenetic Modifications of the PGC-1α Promoter during Exercise Induced Expression in Mice

    PubMed Central

    Lochmann, Timothy L.; Thomas, Ravindar R.; Bennett, James P.; Taylor, Shirley M.

    2015-01-01

    The transcriptional coactivator, PGC-1α, is known for its role in mitochondrial biogenesis. Although originally thought to exist as a single protein isoform, recent studies have identified additional promoters which produce multiple mRNA transcripts. One of these promoters (promoter B), approximately 13.7kb upstream of the canonical PGC-1α promoter (promoter A), yields alternative transcripts present at levels much lower than the canonical PGC-1α mRNA transcript. In skeletal muscle, exercise resulted in a substantial, rapid increase of mRNA of these alternative PGC-1α transcripts. Although the β2-adrenergic receptor was identified as a signaling pathway that activates transcription from PGC-1α promoter B, it is not yet known what molecular changes occur to facilitate PGC-1α promoter B activation following exercise. We sought to determine whether epigenetic modifications were involved in this exercise response in mouse skeletal muscle. We found that DNA hydroxymethylation correlated to increased basal mRNA levels from PGC-1α promoter A, but that DNA methylation appeared to play no role in the exercise-induced activation of PGC-1α promoter B. The level of the activating histone mark H3K4me3 increased with exercise 2–4 fold across PGC-1α promoter B, but remained unaltered past the canonical PGC-1α transcriptional start site. Together, these data show that epigenetic modifications partially explain exercise-induced changes in the skeletal muscle mRNA levels of PGC-1α isoforms. PMID:26053857

  13. Vitamin D2 supplementation amplifies eccentric exercise-induced muscle damage in NASCAR pit crew athletes.

    PubMed

    Nieman, David C; Gillitt, Nicholas D; Shanely, R Andrew; Dew, Dustin; Meaney, Mary Pat; Luo, Beibei

    2014-01-01

    This study determined if 6-weeks vitamin D2 supplementation (vitD2, 3800 IU/day) had an influence on muscle function, eccentric exercise-induced muscle damage (EIMD), and delayed onset of muscle soreness (DOMS) in National Association for Stock Car Auto Racing (NASCAR) NASCAR pit crew athletes. Subjects were randomized to vitD2 (n=13) and placebo (n=15), and ingested supplements (double-blind) for six weeks. Blood samples were collected and muscle function tests conducted pre- and post-study (leg-back and hand grip dynamometer strength tests, body weight bench press to exhaustion, vertical jump, 30-s Wingate test). Post-study, subjects engaged in 90 min eccentric-based exercise, with blood samples and DOMS ratings obtained immediately after and 1- and 2-days post-exercise. Six weeks vitD2 increased serum 25(OH)D2 456% and decreased 25(OH)D3 21% versus placebo (p<0.001, p=0.036, respectively), with no influence on muscle function test scores. The post-study eccentric exercise bout induced EIMD and DOMS, with higher muscle damage biomarkers measured in vitD2 compared to placebo (myoglobin 252%, 122% increase, respectively, p=0.001; creatine phosphokinase 24 h post-exercise, 169%, 32%, p<0.001), with no differences for DOMS. In summary, 6-weeks vitD2 (3800 IU/day) significantly increased 25(OH)D2 and decreased 25(OH)D3, had no effect on muscle function tests, and amplified muscle damage markers in NASCAR pit crew athletes following eccentric exercise. PMID:24362707

  14. Facilitatory effect of paired-pulse stimulation by transcranial magnetic stimulation with biphasic wave-form.

    PubMed

    Julkunen, Petro; Järnefelt, Gustaf; Savolainen, Petri; Laine, Jarmo; Karhu, Jari

    2016-08-01

    Transcranial magnetic stimulation (TMS) is used to probe corticospinal excitability by stimulating the motor cortex. Our aim was to enhance the effects of biphasic TMS by coupling a suprathreshold test pulse and a following subthreshold priming pulse to induce short-interval intracortical facilitation (SICF), which is conventionally produced with monophasic TMS. Biphasic TMS could potentially induce the SICF effect with better energy-efficiency and with lower stimulus intensities. This would make the biphasic paired-pulses better applicable in patients with reduced cortical excitability. A prototype stimulator was built to produce biphasic paired-pulses. Resting motor thresholds (rMTs) from the right and left hand abductor pollicis brevis muscles, and the right tibialis anterior muscle of eight healthy volunteers were determined using single-pulse paradigm with neuronavigated TMS. The rMTs and MEPs were measured using single-pulses and three paired-pulse setups (interstimulus interval, ISI of 3, 7 or 15ms). The rMTs were lower and MEPs were higher with biphasic paired-pulses compared to single-pulses. The SICF effect was greatest at 3ms ISI. This suggests that the application of biphasic paired-pulses to enhance stimulation effects is possible. PMID:27215172

  15. Treadmill Exercise Induces Neutrophil Recruitment into Muscle Tissue in a Reactive Oxygen Species-Dependent Manner. An Intravital Microscopy Study

    PubMed Central

    Nunes-Silva, Albená; Bernardes, Priscila T. T.; Rezende, Bárbara M.; Lopes, Fernando; Gomes, Elisa C.; Marques, Pedro E.; Lima, Paulo M. A.; Coimbra, Cândido C.; Menezes, Gustavo B.; Teixeira, Mauro M.; Pinho, Vanessa

    2014-01-01

    Intense exercise is a physiological stress capable of inducing the interaction of neutrophils with muscle endothelial cells and their transmigration into tissue. Mechanisms driving this physiological inflammatory response are not known. Here, we investigate whether production of reactive oxygen species is relevant for neutrophil interaction with endothelial cells and recruitment into the quadriceps muscle in mice subjected to the treadmill fatiguing exercise protocol. Mice exercised until fatigue by running for 56.3±6.8 min on an electric treadmill. Skeletal muscle was evaluated by intravital microscopy at different time points after exercise, and then removed to assess local oxidative stress and histopathological analysis. We observed an increase in plasma lactate and creatine kinase (CK) concentrations after exercise. The numbers of monocytes, neutrophils, and lymphocytes in blood increased 12 and 24 hours after the exercise. Numbers of rolling and adherent leukocytes increased 3, 6, 12, and 24 hours post-exercise, as assessed by intravital microscopy. Using LysM-eGFP mice and confocal intravital microscopy technology, we show that the number of transmigrating neutrophils increased 12 hours post-exercise. Mutant gp91phox-/- (non-functional NADPH oxidase) mice and mice treated with apocynin showed diminished neutrophil recruitment. SOD treatment promoted further adhesion and transmigration of leukocytes 12 hours after the exercise. These findings confirm our hypothesis that treadmill exercise increases the recruitment of leukocytes to the postcapillary venules, and NADPH oxidase-induced ROS plays an important role in this process. PMID:24798414

  16. Restoration of plasma volume after 16 days of head-down tilt induced by a single bout of maximal exercise

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.; Engelke, K. A.; Ludwig, D. A.; Doerr, D. F.

    1996-01-01

    Seven healthy men performed maximal exercise 24 h before the end of 16 days exposure to 6 degrees head-down tilt (HDT) to test the hypothesis that such an exercise technique could restore plasma volume (PV) at the end of a simulated space mission. Exercise consisted of supine cycling with graded work rates increasing by 16 W/min to volitional fatigue and required an average of 16 min. The experimental protocol was a standard cross-over design in which the order of treatment (exercise or control) was counterbalanced across all seven subjects. PV, fluid intake (ad libitum), urine output, renal function, and hormones associated with fluid homeostasis were measured before HDT, 24 h before the end of HDT just prior to exercise, and at the end of HDT 24 h after exercise. HDT reduced PV by 16% in both control and exercise conditions. Maximal exercise completely restored plasma volume within 24 h to 3.9 +/- 3.2% of pre-HDT levels despite continued HDT. Compared with control, exercise induced a 660-ml larger positive fluid balance because of greater fluid intake and reduced urine volume during the 24 h after exercise. These results suggest that one bout of maximal leg exercise before return from 16 days of spaceflight may be completely effective in stimulating thirst and restoring plasma volume to preflight levels.

  17. Effects of Massage on Muscular Strength and Proprioception After Exercise-Induced Muscle Damage.

    PubMed

    Shin, Mal-Soon; Sung, Yun-Hee

    2015-08-01

    Exercise-induced muscle damage (EIMD), which is commonly associated with eccentric exercise, unaccustomed exercise, and resistance training, may lead to delayed onset muscle soreness, swelling, decreased muscle strength, and range of motion. Many researchers have evaluated various interventions to treat the signs and symptoms of EIMD. However, the effects of massage after EIMD are unclear. Here, we investigated the effect of massage on muscle strength and proprioception after EIMD. All subjects randomly were divided into an EIMD-treated control group (n = 10) and a massage-treated after EIMD experimental group (n = 11). Exercise-induced muscle damage was induced by repeated exercise. Massage treatment was provided by physiotherapist for 15 minutes. It consists of light stroking, milking, friction, and skin rolling. Lactate was evaluated by Lactate Pro analyzer in pre- and postexercise. Surface electromyography (muscle activity) and sonography (muscle thickness) were used to confirm the muscular characteristics. Proprioception was investigated by dual inclinometer. As a result, massage treatment on the gastrocnemius after EIMD increased activation of the medial gastrocnemius during contraction (p ≤ 0.05). In the lateral and medial gastrocnemius, the θs, which is the angle between muscle fibers and superficial aponeurosis, showed a significant change (p ≤ 0.05). However, there are no differences in the θd, which is the angle between muscle fibers and deep aponeurosis. We also found that proprioceptive acuity in the ankle joint was significantly greater in the massage-treated experimental group compared with that in the control group (p ≤ 0.05). These findings suggest that massage of the gastrocnemius after EIMD can improve muscle strength and proprioception by influencing the superficial layer of the gastrocnemius. PMID:25226328

  18. Evidence of local exercise-induced systemic oxidative stress in chronic obstructive pulmonary disease patients.

    PubMed

    Couillard, A; Koechlin, C; Cristol, J P; Varray, A; Prefaut, C

    2002-11-01

    Chronic inactivity may not be the sole factor involved in the myopathy of chronic obstructive pulmonary disease (COPD) patients. One hypothesis is that exercise-induced oxidative stress that leads to muscle alterations may also be involved. This study investigated whether exercise localised to a peripheral muscle group would induce oxidative stress in COPD patients. Eleven COPD patients (FEV1 1.15+/-0.4 L (mean+/-SD)) and 12 healthy age-matched subjects with a similar low quantity of physical activity performed endurance exercise localised to a peripheral muscle group, the quadriceps of the dominant leg. The authors measured plasma levels of thiobarbituric reactive substances (TBARs) as an index of oxidative stress, the release in superoxide anion (O2*-) by stimulated phagocytes as an oxidant, and blood vitamin E as one antioxidant. Quadriceps endurance was significantly lower in the COPD patients compared with healthy subjects (136+/-16 s versus 385+/-69 s (mean+/-SEM), respectively). A significant increase in TBARs 6 h after quadriceps exercise was only found in the COPD patients. In addition, significantly higher O2*- release and lower blood vitamin E levels were found in COPD patients than in controls at rest. This blood vitamin E level was significantly correlated with the resting level of plasma TBARs in the COPD patients. This study mainly showed that quadriceps exercise induced systemic oxidative stress in chronic obstructive pulmonary disease patients and that vitamin E levels were decreased in these patients at rest. The exact relevance of these findings to chronic obstructive pulmonary disease myopathy needs to be elucidated. PMID:12449164

  19. Vitamin D deficiency and exercise-induced laryngospasm in young competitive rowers.

    PubMed

    Heffler, Enrico; Bonini, Matteo; Brussino, Luisa; Solidoro, Paolo; Guida, Giuseppe; Boita, Monica; Nicolosi, Giuliana; Bucca, Caterina

    2016-07-01

    Exercise-induced dyspnea is common among adolescents and young adults and often originates from exercise-induced bronchoconstriction (EIB). Sometimes, dyspnea corresponds to exercise-induced laryngospasm (EILO), which is a paradoxical decrease in supraglottic/glottic area. Vitamin D deficiency, which occurs frequently at northern latitudes, might favor laryngospasm by impairing calcium transport and slowing striate muscle relaxation. The aim of this study was to evaluate whether vitamin D status has an influence on bronchial and laryngeal responses to exercise in young, healthy athletes. EIB and EILO were investigated during winter in 37 healthy competitive rowers (24 males; age range 13-25 years), using the eucapnic voluntary hyperventilation test (EVH). EIB was diagnosed when forced expiratory volume in the first second decreased by 10%, EILO when maximum mid-inspiratory flow (MIF50) decreased by 20%. Most athletes (86.5%) had vitamin D deficiency (below 30 ng/mL), 29 mild-moderate (78.4%) and 3 severe (8.1%). EVH showed EIB in 10 subjects (27%), EILO in 16 (43.2%), and combined EIB and EILO in 6 (16.2%). Athletes with EILO had lower vitamin D (19.1 ng/mL vs. 27.0 ng/mL, p < 0.001) and higher parathyroid hormone (30.5 pg/mL vs. 19.2 pg/mL, p = 0.006) levels. The degree of laryngoconstriction (post-EVH MIF50 as a percentage of pre-EVH MIF50) was related directly with vitamin D levels (r = 0.51; p = 0.001) and inversely with parathyroid hormone levels (r = -0.53; p = 0.001). We conclude that vitamin D deficiency is common during winter in young athletes living above the 40th parallel north and favors laryngospasm during exercise, probably by disturbing calcium homeostasis. This effect may negatively influence athletic performance. PMID:27218140

  20. Exercise Attenuates PCB-Induced Changes in the Mouse Gut Microbiome

    PubMed Central

    Choi, Jeong June; Eum, Sung Yong; Rampersaud, Evadnie; Daunert, Sylvia; Abreu, Maria T.

    2013-01-01

    Background: The gut microbiome, a dynamic bacterial community that interacts with the host, is integral to human health because it regulates energy metabolism and immune functions. The gut microbiome may also play a role in risks from environmental toxicants. Objectives: We investigated the effects of polychlorinated biphenyls (PCBs) and exercise on the composition and structure of the gut microbiome in mice. Methods: After mice exercised voluntarily for 5 weeks, they were treated by oral gavage with a mixture of environmentally relevant PCB congeners (PCB153, PCB138, and PCB180; total PCB dose, 150 µmol/kg) for 2 days. We then assessed the microbiome by determination of 16S rRNA using microarray analysis. Results: Oral exposure to PCBs significantly altered the abundance of the gut microbiome in mice primarily by decreasing the levels of Proteobacteria. The activity level of the mice correlated with a substantial shift in abundance, biodiversity, and composition of the microbiome. Importantly, exercise attenuated PCB-induced changes in the gut microbiome. Conclusions: Our results show that oral exposure to PCBs can induce substantial changes in the gut microbiome, which may then influence their systemic toxicity. These changes can be attenuated by behavioral factors, such as voluntary exercise. PMID:23632211

  1. Bricanyl Turbuhaler and Ventolin Rotahaler in exercise-induced asthma in children.

    PubMed

    dos Santos, J M; Costa, H; Ståhl, E; Wirén, J E

    1991-04-01

    Bricanyl Turbuhaler (0.5 mg terbutaline sulphate) and Ventolin Rotahaler (0.4 mg salbutamol) were compared in a randomized double-blind placebo controlled study on exercise-induced asthma in 19 children (14 boys) aged 7-14 years. The study was carried out on 3 separate days. Asthmatic attacks were provoked by free range running. Peak expiratory flow (PEF) was measured before and after exercise. If PEF decreased by greater than 20%, one inhalation from each of the inhalers was given under supervision of the investigator. Only one of the inhalers (none on the placebo day) delivered active drug. PEF was measured again 5 and 10 min after treatment. Already 5 min after treatment PEF had returned to baseline after active treatment. There was no statistically significant difference between the two active treatments. After placebo treatment, PEF did not return to baseline even at the 10 min post-exercise measurement. Ten children needed extra medication after the last PEF measurement on the placebo day, whereas no child needed extra medication after any of the active treatments. No adverse events were reported in this study. In conclusion, Bricanyl Turbuhaler (0.5 mg) and Ventolin Rotahaler (0.4 mg) were equally efficacious in the treatment of exercise-induced asthma in children. PMID:2058816

  2. Exercise induces hippocampal BDNF through a PGC-1α/FNDC5 pathway

    PubMed Central

    Wrann, Christiane D.; White, James P.; Salogiannnis, John; Laznik-Bogoslavski, Dina; Wu, Jun; Ma, Di; Lin, Jiandie D.; Greenberg, Michael E.; Spiegelman, Bruce M.

    2014-01-01

    SUMMARY Exercise can improve cognitive function and has been linked to the increased expression of brain-derived neurotrophic factor (BDNF). However, the underlying molecular mechanisms driving the elevation of this neurotrophin remain unknown. Here we show that FNDC5, a previously identified muscle protein that is induced in exercise and is cleaved and secreted as irisin, is also elevated by endurance exercise in the hippocampus of mice. Neuronal Fndc5 gene expression is regulated by PGC-1α and Pgc1a−/− mice show reduced Fndc5 expression in the brain. Forced expression of FNDC5 in primary cortical neurons increases Bdnf expression, whereas RNAi-mediated knockdown of FNDC5 reduces Bdnf. Importantly, peripheral delivery of FNDC5 to the liver via adenoviral vectors, resulting in elevated blood irisin, induces expression of Bdnf and other neuroprotective genes in the hippocampus. Taken together, our findings link endurance exercise and the important metabolic mediators, PGC-1α and FNDC5, with BDNF expression in the brain. PMID:24120943

  3. Exercise-induced myalgia may limit the cardiovascular benefits of statins.

    PubMed

    Opie, Lionel H

    2013-12-01

    The positive health benefits of statins extend beyond the cardiovascular and include increased flow mediated dilation, decreased atrial fibrillation, modest antihypertensive effects and reduced risks of malignancies. Prominent among the statin side-effects are myalgia and muscular weakness, which may be associated with a rise in circulating creatine kinase values. In increasing severity and decreasing incidence, the statin-induced muscle related conditions are myalgia, myopathy with elevated creatine kinase (CK) levels with or without symptoms, and rhabdomyolysis. Statin use may increase CK levels without decreasing average muscle strength or exercise performance. In one large study, only about 2 % had myalgia that could be attributed to statin use. A novel current hypothesis is that statins optimize cardiac mitochondrial function but impair the vulnerable skeletal muscle by inducing different levels of reactive oxygen species (ROS) in these two sites. In an important observational study, both statins and exercise reduced the adverse outcomes of cardiovascular disease, and the effects were additive. The major unresolved problem is that either can cause muscular symptoms with elevation of blood creatine kinase levels. There is, as yet, no clearly defined outcomes based policy to deal with such symptoms from use of either statins or exercise or both. A reasonable practical approach is to assess the creatine kinase levels, and if elevated to reduce the statin dose or the intensity of exercise. PMID:23934075

  4. Potassium-induced ventilatory reflexes originating from the dog hindlimb during rest and passive exercise.

    PubMed

    Leite-de-Barros-Neto, T; Russo, A K; Da Silva, A C; Piçarro, I C; Griggio, M A; Tarasantchi, J

    1981-10-01

    1. It has been previously shown that Ketalar-anesthetized dogs do not exhibit alterations either in ventilation or in oxygen uptake during passive motion. In the present study, the same model was used to study the effects induced by increasing extracellular K+ to the concentration achieved during active exercise. 2. The isolated hindlimbs of twelve dogs anesthetized with ketamine hydrochloride i.v., after induction with sodium pentobarbital, were perfused with control (2.8 mM KCl) and experimental (8 mM KCl) physiological solutions under resting conditions, and in passive motion. 3. Respiratory minute volume (VE), respiratory rate (f) and tidal volume (VT) were determined by collecting the expired air in a Tissot gasometer. 4. During the control perfusion, the values of VE, f and VT for passive exercise did not differ significantly from those obtained under resting conditions. However, during perfusion with 8 mM KCl, a significant increase in VE was observed, possibly due to an increase of VT under resting conditions and to an increase of f during passive exercise. 5. The results suggest that passive exercise can induce a significant increase in ventilation only when accompanied by local chemical changes such as an increase in extracellular K+. PMID:7344748

  5. Kinetics of exercise-induced neural activation; interpretive dilemma of altered cerebral perfusion.

    PubMed

    Miyazawa, Taiki; Horiuchi, Masahiro; Ichikawa, Daisuke; Sato, Kohei; Tanaka, Naoki; Bailey, Damian M; Ogoh, Shigehiko

    2012-02-01

    Neural activation decreases cerebral deoxyhaemoglobin (HHb(C)) and increases oxyhaemoglobin concentration (O(2)Hb(C)). In contrast, patients who present with restricted cerebral blood flow, such as those suffering from cerebral ischaemia or Alzheimer's disease, and during the course of ageing the converse occurs, in that HHb(C) increases and O(2)Hb(C) decreases during neural activation. In the present study, we examined the interpretive implications of altered exercise-induced cerebral blood flow for cortical oxygenation in healthy subjects. Both O(2)Hb(C) and HHb(C) (prefrontal cortex) were determined in 11 healthy men using near-infrared spectroscopy (NIRS). Middle cerebral artery mean blood velocity (MCA V(mean)) was determined via transcranial Doppler ultrasonography. Measurements were performed during contralateral hand-grip exercise during suprasystolic bilateral thigh-cuff occlusion (Cuff+) and within 2 s of cuff release (Cuff-) for the acute manipulation of cerebral perfusion. During Cuff+, both MCA V(mean) and O(2)Hb(C) increased during exercise, whereas HHb(C) decreased. In contrast, the opposite occurred during the Cuff- manipulation. These findings highlight the inverse relationship between cerebral blood flow and cerebral oxygenation as determined by NIRS, which has interpretive implications for the kinetics underlying exercise-induced neural activation. PMID:22041980

  6. Exercise protocol induces muscle, tendon, and bone adaptations in the rat shoulder

    PubMed Central

    Rooney, Sarah Ilkhanipour; Loro, Emanuele; Sarver, Joseph J.; Peltz, Cathryn D.; Hast, Michael W.; Tseng, Wei-Ju; Kuntz, Andrew F.; Liu, X. Sherry; Khurana, Tejvir S.; Soslowsky, Louis J.

    2014-01-01

    Summary Background: a rat model of supraspinatus overuse has suggested mechanisms governing tendon degeneration; however, delineating which changes are pathologic or simply physiologic adaptations to increased loading remains a question. The objective of this study was to develop and characterize a rat exercise model that induces systemic and local shoulder adaptations without mechanical injury to the supraspinatus tendon. Methods: exercise rats completed a treadmill training protocol for 12 weeks. Body, fat pad, and heart weights were determined. Supraspinatus tendon collagen content, cross-sectional area, and mechanical properties were measured. Supraspinatus muscle cross-sectional area, weight, and the expression of mitochondrial oxidative phosphorylation (OXPHOS) proteins were measured. Humeri were analyzed with μCT and mechanically tested. Results: exercise decreased fat pad mass. Supraspinatus muscle hypertrophied and had increased OXPHOS proteins. Humerus trabecular bone had increased anisotropic orientation, and cortical bone showed increased bone and tissue mineral density. Importantly, the supraspinatus tendon did not have diminished mechanical properties, indicating that this protocol was not injurious to the tendon. Conclusion: this study establishes the first rat exercise protocol that induces adaptations in the shoulder. Future research can use this as a comparison model to study how the supraspinatus tendon adapts to loading and undergoes degeneration with overuse. PMID:25767777

  7. A Systematic Review of the Literature on Screening for Exercise-Induced Asthma: Considerations for School Nurses

    ERIC Educational Resources Information Center

    Worrell, Kelly; Shaw, Michele R.; Postma, Julie; Katz, Janet R.

    2015-01-01

    Asthma is a major cause of illness, missed school days, and hospitalization in children. One type of asthma common in children is exercise-induced asthma (EIA). EIA causes airway narrowing with symptoms of cough and shortness of breath during exercise. The purpose of this article is to review the literature relevant to screening children and…

  8. Acute Exercise-Induced Response of Monocyte Subtypes in Chronic Heart and Renal Failure

    PubMed Central

    Van Craenenbroeck, Amaryllis H.; Hoymans, Vicky Y.; Verpooten, Gert A.; Vrints, Christiaan J.; Couttenye, Marie M.; Van Craenenbroeck, Emeline M.

    2014-01-01

    Purpose. Monocytes (Mon1-2-3) play a substantial role in low-grade inflammation associated with high cardiovascular morbidity and mortality of patients with chronic kidney disease (CKD) and chronic heart failure (CHF). The effect of an acute exercise bout on monocyte subsets in the setting of systemic inflammation is currently unknown. This study aims (1) to evaluate baseline distribution of monocyte subsets in CHF and CKD versus healthy subjects (HS) and (2) to evaluate the effect of an acute exercise bout. Exercise-induced IL-6 and MCP-1 release are related to the Mon1-2-3 response. Methods. Twenty CHF patients, 20 CKD patients, and 15 HS were included. Before and after a maximal cardiopulmonary exercise test, monocyte subsets were quantified by flow cytometry: CD14++CD16−CCR2+ (Mon1), CD14++CD16+CCR2+ (Mon2), and CD14+CD16++CCR2− (Mon3). Serum levels of IL-6 and MCP-1 were determined by ELISA. Results. Baseline distribution of Mon1-2-3 was comparable between the 3 groups. Following acute exercise, %Mon2 and %Mon3 increased significantly at the expense of a decrease in %Mon1 in HS and in CKD. This response was significantly attenuated in CHF (P < 0.05). In HS only, MCP-1 levels increased following exercise; IL-6 levels were unchanged. Circulatory power was a strong and independent predictor of the changes in Mon1 (β = −0.461, P < 0.001) and Mon3 (β = 0.449, P < 0.001); and baseline LVEF of the change in Mon2 (β = 0.441, P < 0.001). Conclusion. The response of monocytes to acute exercise is characterized by an increase in proangiogenic and proinflammatory Mon2 and Mon3 at the expense of phagocytic Mon1. This exercise-induced monocyte subset response is mainly driven by hemodynamic changes and not by preexistent low-grade inflammation. PMID:25587208

  9. Combination of exercise training and diet restriction normalizes limited exercise capacity and impaired skeletal muscle function in diet-induced diabetic mice.

    PubMed

    Suga, Tadashi; Kinugawa, Shintaro; Takada, Shingo; Kadoguchi, Tomoyasu; Fukushima, Arata; Homma, Tsuneaki; Masaki, Yoshihiro; Furihata, Takaaki; Takahashi, Masashige; Sobirin, Mochamad A; Ono, Taisuke; Hirabayashi, Kagami; Yokota, Takashi; Tanaka, Shinya; Okita, Koichi; Tsutsui, Hiroyuki

    2014-01-01

    Exercise training (EX) and diet restriction (DR) are essential for effective management of obesity and insulin resistance in diabetes mellitus. However, whether these interventions ameliorate the limited exercise capacity and impaired skeletal muscle function in diabetes patients remains unexplored. Therefore, we investigated the effects of EX and/or DR on exercise capacity and skeletal muscle function in diet-induced diabetic mice. Male C57BL/6J mice that were fed a high-fat diet (HFD) for 8 weeks were randomly assigned for an additional 4 weeks to 4 groups: control, EX, DR, and EX+DR. A lean group fed with a normal diet was also studied. Obesity and insulin resistance induced by a HFD were significantly but partially improved by EX or DR and completely reversed by EX+DR. Although exercise capacity decreased significantly with HFD compared with normal diet, it partially improved with EX and DR and completely reversed with EX+DR. In parallel, the impaired mitochondrial function and enhanced oxidative stress in the skeletal muscle caused by the HFD were normalized only by EX+DR. Although obesity and insulin resistance were completely reversed by DR with an insulin-sensitizing drug or a long-term intervention, the exercise capacity and skeletal muscle function could not be normalized. Therefore, improvement in impaired skeletal muscle function, rather than obesity and insulin resistance, may be an important therapeutic target for normalization of the limited exercise capacity in diabetes. In conclusion, a comprehensive lifestyle therapy of exercise and diet normalizes the limited exercise capacity and impaired muscle function in diabetes mellitus. PMID:24189138

  10. The effects of caffeine ingestion on exercise-induced hypoalgesia: A pilot study.

    PubMed

    Black, Christopher D; Gonglach, Alexander R; Renfroe, Jessica B; Hight, Robert E

    2016-07-01

    Exercise acutely reduces pain sensitivity, termed exercise-induced hypoalgesia (EIH). The mechanisms underlying EIH remain unclear. Caffeine, a non-specific adenosine receptor antagonist has been shown to attenuate EIH in animals-suggesting the involvement of the adenosinergic system. This pilot study investigated the effects of caffeine on pain sensitivity following cycling exercise in college-aged men. Pressure pain threshold (PPT) and thermal pain threshold (TPT) were assessed in thirteen low caffeine consuming men prior to ingestion of a counter-balanced 5mg·kg(-1) dose of caffeine or a placebo (Pre), 60min following ingestion (Post-In), and then following a 15min bout of cycling exercise (Post-Ex) at an intensity eliciting a quadriceps muscle pain rating of 3 out of 10. Nine of the men completed follow-up testing which was identical except that the exercise consisted of 10min of cycling eliciting a pain rating of 5 out of 10. Caffeine had no effect compared to placebo on PPT (p≥0.15) or TPT (p≥0.41) 60min following ingestion and following exercise. PPT increased from 599±176kPa to 648±202kPa (p=0.009) and from 578±217kPa to 666±278kPa (p=0.01) following 15 and 10min of cycling, respectively. TPT increased from 46.2±2.9°C to 46.8±2.6°C (p=0.008) following the 15min exercise bout, but did not change (46.4±3.6°C vs. 46.8±3.3°C; p=0.24) following the shorter, higher intensity exercise bout. The results from this study indicate cycling exercise reduces pain sensitivity, especially to pressure stimuli. Caffeine ingestion did not alter the EIH response-suggesting adenosine may not play a prominent role in the EIH response in humans. PMID:27063247

  11. Effects of exercise-induced muscle damage on resting metabolic rate, sub-maximal running and post-exercise oxygen consumption.

    PubMed

    Burt, Dean Gareth; Lamb, Kevin; Nicholas, Ceri; Twist, Craig

    2014-01-01

    Exercise-induced muscle damage (EIMD), described as the acute weakness of the musculature after unaccustomed eccentric exercise, increases oxidative metabolism at rest and during endurance exercise. However, it is not known whether oxygen uptake during recovery from endurance exercise is increased when experiencing symptoms of EIMD. Therefore, the purpose of this study was to investigate the effects of EIMD on physiological and metabolic responses before, during and after sub-maximal running. After a 12 h fast, eight healthy male participants completed baseline measurements comprising resting metabolic rate (RMR), indirect markers of EIMD, 10 min of sub-maximal running and 30 min of recovery to ascertain excess post-exercise oxygen consumption (EPOC). Measurements were then repeated at 24 and 48 h after 100 Smith-machine squats. Data analysis revealed significant (P<0.05) increases in muscle soreness and creatine kinase (CK) and decreases in peak knee extensor torque at 24 and 48 h after squatting exercise. Moreover, RMR, physiological, metabolic and perceptual responses during sub-maximal running and EPOC were increased in the two days after squatting exercise (P<0.05). It is suggested that the elevated RMR was a consequence of a raised energy requirement for the degradation and resynthesis of damaged muscle fibres. The increased oxygen demand during sub-maximal running after muscle damage was responsible for the increase in EPOC. Individuals engaging in unaccustomed resistance exercise that results in muscle damage should be mindful of the increases in resting energy expenditure and increased metabolic demand to exercise in the days that follow. PMID:23566074

  12. Impact-driven, pulmonary emboli of osseous fat in exercise-induced bronchospasm.

    PubMed

    Simkin, Peter A; Snitily, Brian K

    2015-11-01

    Exercise induced bronchospasm (EIB) affects approximately 10% of normal individuals with higher prevalence rates among children, obese adults, and competitive athletes. Although hyperpnea with dry air is the best known cause, the problem is multifactorial with atopy, asthma and chlorine all playing established roles. To date, no clear mechanism has connected musculoskeletal loading with the ensuing pulmonary compromise. This paper reviews evidence that impact-driven pulses in subchondral bone pressure may push osseous fat cells into the local venous sinusoids. The resultant showers of microemboli must then travel to the lung where lysis of membrane phospholipids leads to leukotriene formation with resultant inflammation and bronchial hypersensitivity. Concurrently, the same emboli deliver triglyceride fuels for further physical activity. Thus, pulmonary microemboli derived from osseous fat may resolve the seeming paradox of athletic excellence in persons afflicted with exercise-induced bronchospasm. PMID:26328480

  13. Biphasic nature of gastric emptying.

    PubMed

    Siegel, J A; Urbain, J L; Adler, L P; Charkes, N D; Maurer, A H; Krevsky, B; Knight, L C; Fisher, R S; Malmud, L S

    1988-01-01

    The existence of a lag phase during the gastric emptying of solid foods is controversial. It has been hypothesised that among other early events, the stomach requires a period of time to process solid food to particles small enough to be handled as a liquid. At present no standardised curve fitting techniques exist for the characterisation and quantification of the lag phase or the emptying rate of solids and liquids. We have evaluated the ability of a modified power exponential function to define the emptying parameters of two different solid meals. Dual labelled meals were administered to 24 normal volunteers. The subjects received meals consisting of either Tc-99m in vivo labelled chicken liver or Tc-99m-egg, which have different densities, and In-111-DTPA in water. The emptying curves were biphasic in nature. For solids, this represented an initial delay in emptying or lag phase followed by an equilibrium emptying phase characterised by a constant rate of emptying. The curves were analysed using a modified power exponential function of the form y(t) = 1-(1-e-kt)beta, where y(t) is the fractional meal retention at time t, k is the gastric emptying rate in min-1, and beta is the extrapolated y-intercept from the terminal portion of the curve. The length of the lag phase and half-emptying time increased with solid food density (31 +/- 8 min and 77.6 +/- 11.2 min for egg and 62 +/- 16 min and 94.1 +/- 14.2 min for chicken liver, respectively). After the lag phase, both solids had similar emptying rates, and these rates were identical to those of the liquids. In vitro experiments indicated that the egg meal disintegrated much more rapidly than the chicken liver under mechanical agitation in gastric juice, lending further support to the hypothesis that the initial lag in emptying of solid food is due to the processing of food into particles small enough to pass the pylorus. We conclude that the modified power exponential model permits characterisation of the biphasic

  14. Exercise-Induced Cognitive Plasticity, Implications for Mild Cognitive Impairment and Alzheimer’s Disease

    PubMed Central

    Foster, Philip P.; Rosenblatt, Kevin P.; Kuljiš, Rodrigo O.

    2011-01-01

    Lifestyle factors such as intellectual stimulation, cognitive and social engagement, nutrition, and various types of exercise appear to reduce the risk for common age-associated disorders such as Alzheimer’s disease (AD) and vascular dementia. In fact, many studies have suggested that promoting physical activity can have a protective effect against cognitive deterioration later in life. Slowing or a deterioration of walking speed is associated with a poor performance in tests assessing psychomotor speed and verbal fluency in elderly individuals. Fitness training influences a wide range of cognitive processes, and the largest positive impact observed is for executive (a.k.a. frontal lobe) functions. Studies show that exercise improves additional cognitive functions such as tasks mediated by the hippocampus, and result in major changes in plasticity in the hippocampus. Interestingly, this exercise-induced plasticity is also pronounced in APOE ε4 carriers who express a risk factor for late-onset AD that may modulate the effect of treatments. Based on AD staging by Braak and Braak (1991) and Braak et al. (1993) we propose that the effects of exercise occur in two temporo-spatial continua of events. The “inward” continuum from isocortex (neocortex) to entorhinal cortex/hippocampus for amyloidosis and a reciprocal “outward” continuum for neurofibrillary alterations. The exercise-induced hypertrophy of the hippocampus at the core of these continua is evaluated in terms of potential for prevention to stave off neuronal degeneration. Exercise-induced production of growth factors such as the brain-derived neurotrophic factor (BDNF) has been shown to enhance neurogenesis and to play a key role in positive cognitive effects. Insulin-like growth factor (IGF-1) may mediate the exercise-induced response to exercise on BDNF, neurogenesis, and cognitive performance. It is also postulated to regulate brain amyloid β (Aβ) levels by increased clearance via the choroid

  15. Effects of Exercise Induced Low Back Pain on Intrinsic Trunk Stiffness and Paraspinal Muscle Reflexes

    PubMed Central

    Miller, Emily M.; Bazrgari, Babak; Nussbaum, Maury A.; Madigan, Michael L.

    2012-01-01

    The purpose of this study was to 1) compare trunk neuromuscular behavior between individuals with no history of low back pain (LBP) and individuals who experience exercise-induced LBP (eiLBP) when pain free, and 2) investigate changes in trunk neuromuscular behavior with eiLBP. Seventeen young adult males participated including eight reporting recurrent, acute eiLBP and nine control participants reporting no history of LBP. Intrinsic trunk stiffness and paraspinal muscle reflex delay were determined in both groups using sudden trunk flexion position perturbations 1-2 days following exercise when the eiLBP participants were experiencing an episode of LBP (termed post-exercise) and 4-5 days following exercise when eiLBP had subsided (termed post-recovery). Post-recovery, when the eiLBP group was experiencing minimal LBP, trunk stiffness was 26% higher in the eiLBP group compared to the control group (p=0.033) and reflex delay was not different (p=0.969) between groups. Trunk stiffness did not change (p=0.826) within the eiLBP group from post-exercise to post-recovery, but decreased 22% within the control group (p=0.002). Reflex delay decreased 11% within the eiLBP group from post-exercise to post-recovery (p=0.013), and increased 15% within the control group (p=0.006). Although the neuromuscular mechanisms associated with eiLBP and chronic LBP may differ, these results suggest that previously-reported differences in trunk neuromuscular behavior between individuals with chronic LBP and healthy controls reflect a combination of inherent differences in neuromuscular behavior between these individuals as well as changes in neuromuscular behavior elicited by pain. PMID:23182221

  16. Running wheel exercise enhances recovery from nigrostriatal dopamine injury without inducing neuroprotection.

    PubMed

    O'Dell, S J; Gross, N B; Fricks, A N; Casiano, B D; Nguyen, T B; Marshall, J F

    2007-02-01

    Forced use of the forelimb contralateral to a unilateral injection of the dopaminergic neurotoxin 6-hydroxydopamine can promote recovery of motor function in that limb and can significantly decrease damage to dopamine terminals. The present study was conducted to determine (1) whether a form of voluntary exercise, wheel running, would improve motor performance in rats with such lesions, and (2) whether any beneficial effects of wheel running are attributable to ameliorating the dopaminergic damage. In experiment 1, rats were allowed to run in exercise wheels or kept in home cages for 2 1/2 weeks, then given stereotaxic infusions of 6-hydroxydopamine into the left striatum. The rats were replaced into their original environments (wheels or home cages) for four additional weeks, and asymmetries in forelimb use were quantified at 3, 10, 17, and 24 days postoperatively. After killing, dopaminergic damage was assessed by both quantifying 3 beta-(4-iodophenyl)tropan-2 beta-carboxylic acid methyl ester ([(125)I]RTI-55) binding to striatal dopamine transporters and counting tyrosine hydroxylase-positive cells in the substantia nigra. Exercised 6-hydroxydopamine-infused rats showed improved motor outcomes relative to sedentary lesioned controls, effects that were most apparent at postoperative days 17 and 24. Despite this behavioral improvement, 6-hydroxydopamine-induced loss of striatal dopamine transporters and tyrosine hydroxylase-positive nigral cells in exercised and sedentary groups did not differ. Since prior studies suggested that forced limb use improves motor performance by sparing nigrostriatal dopaminergic neurons from 6-hydroxydopamine damage, experiment 2 used a combined regimen of forced plus voluntary wheel running. Again, we found that the motor performance of exercised rats improved more rapidly than that of sedentary controls, but that there were no differences between these groups in the damage produced by 6-hydroxydopamine. It appears that voluntary

  17. Roles of exercise and pharmacokinetics in cerivastatin-induced skeletal muscle toxicity.

    PubMed

    Seachrist, Jennifer L; Loi, Cho-Ming; Evans, Mark G; Criswell, Kay A; Rothwell, Charles E

    2005-12-01

    Three-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are associated with adverse skeletal muscle effects, but the underlying mechanisms remain unclear. To determine whether toxicity involves the level of drug exposure in muscle tissue and to test the effect of exercise on cerivastatin (CVA)-induced skeletal muscle damage, female rats were administered vehicle or CVA at 0.1, 0.5, and 1.0 mg/kg/day by gavage for two weeks and exercised or not on treadmills for 20 min/day. Clinical chemistry and plasma and tissue pharmacokinetics were evaluated; light and transmission electron microscopy (TEM) of Type I and Type II fiber-predominant skeletal muscles were performed. Serum levels of AST, ALT, CK, and plasma lactic acid were significantly elevated dose-dependently. CVA treatment decreased psoas and quadriceps weights. At 1 mg/kg all muscles except soleus demonstrated degeneration. Exercise-exacerbated severity of CVA-induced degeneration was evident in all muscles sampled except soleus and quadriceps. Early mitochondrial involvement in toxicity is suggested by the numerous membranous whorls and degenerate mitochondria observed in muscles at 0.5 mg/kg. No significant differences in CVA concentrations between either EDL and soleus or plasma and muscle were found. We found that CVA had no effect on cleaved caspase 3. In summary, we found that treadmill exercise exacerbated the incidence and severity of CVA-induced damage in Type II fiber-predominant muscles. Tissue exposure is likely not the key factor mediating CVA-induced skeletal muscle toxicity. PMID:16141437

  18. The Biphasic Effects of Moderate Alcohol Consumption with a Meal on Ambiance-Induced Mood and Autonomic Nervous System Balance: A Randomized Crossover Trial

    PubMed Central

    Schrieks, Ilse C.; Stafleu, Annette; Kallen, Victor L.; Grootjen, Marc; Witkamp, Renger F.; Hendriks, Henk F. J.

    2014-01-01

    Background The pre-drinking mood state has been indicated to be an important factor in the mood effects of alcohol. However, for moderate alcohol consumption there are no controlled studies showing this association. Also, the mood effects of consuming alcohol combined with food are largely unknown. The aim of this study was to investigate the effects of moderate alcohol combined with a meal on ambiance-induced mood states. Furthermore effects on autonomic nervous system activity were measured to explore physiological mechanisms that may be involved in changes of mood state. Methods In a crossover design 28 women (age 18–45 y, BMI 18.5–27 kg/m2) were randomly allocated to 4 conditions in which they received 3 glasses of sparkling white wine (30 g alcohol) or alcohol-free sparkling white wine while having dinner in a room with either a pleasant or unpleasant created ambiance. Subjects filled out questionnaires (B-BAES, POMS and postprandial wellness questionnaire) at different times. Skin conductance and heart rate variability were measured continuously. Results Moderate alcohol consumption increased happiness scores in the unpleasant, but not in the pleasant ambiance. Alcohol consumption increased happiness and stimulation feelings within 1 hour and increased sedative feelings and sleepiness for 2.5 hour. Skin conductance was increased after alcohol within 1 hour and was related to happiness and stimulation scores. Heart rate variability was decreased after alcohol for 2 hours and was related to mental alertness. Conclusion Mood inductions and autonomic nervous system parameters may be useful to evaluate mood changes by nutritional interventions. Moderate alcohol consumption elevates happiness scores in an unpleasant ambiance. However, drinking alcohol during a pleasant mood results in an equally positive mood state. Trial Registration Clinicaltrials.gov NCT01426022. PMID:24465955

  19. Biphasic Effects of Nitric Oxide Radicals on Radiation-Induced Lethality and Chromosome Aberrations in Human Lung Cancer Cells Carrying Different p53 Gene Status

    SciTech Connect

    Su Xiaoming; Takahashi, Akihisa; Guo Guozhen; Mori, Eiichiro; Okamoto, Noritomo; Ohnishi, Ken; Iwasaki, Toshiyasu; Ohnishi, Takeo

    2010-06-01

    Purpose: The aim of this study was to clarify the effects of nitric oxide (NO) on radiation-induced cell killing and chromosome aberrations in two human lung cancer cell lines with a different p53 gene status. Methods and Materials: We used wild-type (wt) p53 and mutated (m) p53 cell lines that were derived from the human lung cancer H1299 cell line, which is p53 null. The wtp53 and mp53 cell lines were generated by transfection of the appropriate p53 constructs into the parental cells. Cells were pretreated with different concentrations of isosorbide dinitrate (ISDN) (an NO donor) and/or 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO) (an NO scavenger) and then exposed to X-rays. Cell survival, apoptosis, and chromosome aberrations were scored by use of a colony-forming assay, Hoechst 33342 staining assay and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP [deoxyuridine triphosphate] nick end labeling) assay, and chromosomal banding techniques, respectively. Results: In wtp53 cells the induction of radioresistance and the inhibition of apoptosis and chromosome aberrations were observed in the presence of ISDN at low 2- to 10-{mu}mol/L concentrations before X-irradiation. The addition of c-PTIO and ISDN into the culture medium 6 h before irradiation almost completely suppressed these effects. However, at high concentrations of ISDN (100-500 {mu}mol/L), clear evidence of radiosensitization, enhancement of apoptosis, and chromosome aberrations was detected. However, these phenomena were not observed in mp53 cells at either concentration range with ISDN. Conclusions: These results indicate that low and high concentrations of NO radicals can choreograph inverse radiosensitivity, apoptosis, and chromosome aberrations in human lung cancer cells and that NO radicals can affect the fate of wtp53 cells.

  20. Biphasic calcium phosphate in periapical surgery

    PubMed Central

    Suneelkumar, Chinni; Datta, Krithika; Srinivasan, Manali R; Kumar, Sampath T

    2008-01-01

    Calcium phosphate ceramics like hydroxyapatite and β -tricalcium phosphate (β -TCP) possess mineral composition that closely resembles that of the bone. They can be good bone substitutes due to their excellent biocompatibility. Biphasic calcium phosphate is a bone substitute which is a mixture of hydroxyapatite and β -tricalcium phosphate in fixed ratios. Studies have demonstrated the osteoconductive potential of this composition. This paper highlights the clinical use of biphasic calcium phosphate as a bone substitute in periapical surgery. PMID:20142892

  1. Acute and chronic watercress supplementation attenuates exercise-induced peripheral mononuclear cell DNA damage and lipid peroxidation.

    PubMed

    Fogarty, Mark C; Hughes, Ciara M; Burke, George; Brown, John C; Davison, Gareth W

    2013-01-28

    Pharmacological antioxidant vitamins have previously been investigated for a prophylactic effect against exercise-induced oxidative stress. However, large doses are often required and may lead to a state of pro-oxidation and oxidative damage. Watercress contains an array of nutritional compounds such as β-carotene and α-tocopherol which may increase protection against exercise-induced oxidative stress. The present randomised controlled investigation was designed to test the hypothesis that acute (consumption 2 h before exercise) and chronic (8 weeks consumption) watercress supplementation can attenuate exercise-induced oxidative stress. A total of ten apparently healthy male subjects (age 23 (SD 4) years, stature 179 (SD 10) cm and body mass 74 (SD 15) kg) were recruited to complete the 8-week chronic watercress intervention period (and then 8 weeks of control, with no ingestion) of the experiment before crossing over in order to compete the single-dose acute phase (with control, no ingestion). Blood samples were taken at baseline (pre-supplementation), at rest (pre-exercise) and following exercise. Each subject completed an incremental exercise test to volitional exhaustion following chronic and acute watercress supplementation or control. The main findings show an exercise-induced increase in DNA damage and lipid peroxidation over both acute and chronic control supplementation phases (P< 0.05 v. supplementation), while acute and chronic watercress attenuated DNA damage and lipid peroxidation and decreased H₂O₂ accumulation following exhaustive exercise (P< 0.05 v. control). A marked increase in the main lipid-soluble antioxidants (α-tocopherol, γ-tocopherol and xanthophyll) was observed following watercress supplementation (P< 0.05 v. control) in both experimental phases. These findings suggest that short- and long-term watercress ingestion has potential antioxidant effects against exercise-induced DNA damage and lipid peroxidation. PMID:22475430

  2. Increased renal tubular sodium reabsorption during exercise-induced hypervolemia in humans

    NASA Technical Reports Server (NTRS)

    Nagashima, K.; Wu, J.; Kavouras, S. A.; Mack, G. W.

    2001-01-01

    We tested the hypothesis that renal tubular Na(+) reabsorption increased during the first 24 h of exercise-induced plasma volume expansion. Renal function was assessed 1 day after no-exercise control (C) or intermittent cycle ergometer exercise (Ex, 85% of peak O(2) uptake) for 2 h before and 3 h after saline loading (12.5 ml/kg over 30 min) in seven subjects. Ex reduced renal blood flow (p-aminohippurate clearance) compared with C (0.83 +/- 0.12 vs. 1.49 +/- 0.24 l/min, P < 0.05) but did not influence glomerular filtration rates (97 +/- 10 ml/min, inulin clearance). Fractional tubular reabsorption of Na(+) in the proximal tubules was higher in Ex than in C (P < 0.05). Saline loading decreased fractional tubular reabsorption of Na(+) from 99.1 +/- 0.1 to 98.7 +/- 0.1% (P < 0.05) in C but not in Ex (99.3 +/- 0.1 to 99.4 +/- 0.1%). Saline loading reduced plasma renin activity and plasma arginine vasopressin levels in C and Ex, although the magnitude of decrease was greater in C (P < 0.05). These results indicate that, during the acute phase of exercise-induced plasma volume expansion, increased tubular Na(+) reabsorption is directed primarily to the proximal tubules and is associated with a decrease in renal blood flow. In addition, saline infusion caused a smaller reduction in fluid-regulating hormones in Ex. The attenuated volume-regulatory response acts to preserve distal tubular Na(+) reabsorption during saline infusion 24 h after exercise.

  3. Update on the Mechanisms of Pulmonary Inflammation and Oxidative Imbalance Induced by Exercise

    PubMed Central

    Araneda, O. F.; Carbonell, T.; Tuesta, M.

    2016-01-01

    The mechanisms involved in the generation of oxidative damage and lung inflammation induced by physical exercise are described. Changes in lung function induced by exercise involve cooling of the airways, fluid evaporation of the epithelial surface, increased contact with polluting substances, and activation of the local and systemic inflammatory response. The present work includes evidence obtained from the different types of exercise in terms of duration and intensity, the effect of both acute performance and chronic performance, and the influence of special conditions such as cold weather, high altitude, and polluted environments. Levels of prooxidants, antioxidants, oxidative damage to biomolecules, and cellularity, as well as levels of soluble mediators of the inflammatory response and its effects on tissues, are described in samples of lung origin. These samples include tissue homogenates, induced sputum, bronchoalveolar lavage fluid, biopsies, and exhaled breath condensate obtained in experimental protocols conducted on animal and human models. Finally, the need to simultaneously explore the oxidative/inflammatory parameters to establish the interrelation between them is highlighted. PMID:26881028

  4. Sex Differences in Exercise-Induced Muscle Pain and Muscle Damage

    PubMed Central

    Dannecker, Erin A.; Liu, Ying; Rector, R. Scott; Thomas, Tom R.; Fillingim, Roger B.; Robinson, Michael E.

    2012-01-01

    There is uncertainty about sex differences in exercise-induced muscle pain and muscle damage due to several methodological weaknesses in the literature. This investigation tested the hypothesis that higher levels of exercise-induced muscle pain and muscle damage indicators would be found in women than men when several methodological improvements were executed in the same study. Participants (N = 33; 42% women) with an average age of 23 years (SD = 2.82) consented to participate. After a familiarization session, participants visited the laboratory before and across four days after eccentric exercise was completed to induce arm muscle pain and muscle damage. Our primary outcomes were arm pain ratings and pressure pain thresholds. However, we also measured the following indicators of muscle damage: arm girth; resting elbow extension; isometric elbow flexor strength; myoglobin (Mb); tumor necrosis factor (TNFa); interleukin 1beta (IL1b); and total nitric oxide (NO). Temporary induction of muscle damage was indicated by changes in all outcome measures except TNFa, and IL1b. In contrast to our hypotheses, women reported moderately lower and less frequent muscle pain than men. Also, women’s arm girth and Mb levels increased moderately less than men’s, but the differences were not significant. Few large sex differences were detected. PMID:23182229

  5. Exercise-induced neuroprotection in the spastic Han Wistar rat: the possible role of brain-derived neurotrophic factor.

    PubMed

    Van Kummer, Brooke H; Cohen, Randy W

    2015-01-01

    Moderate aerobic exercise has been shown to enhance motor skills and protect the nervous system from neurodegenerative diseases, like ataxia. Our lab uses the spastic Han Wistar rat as a model of ataxia. Mutant rats develop forelimb tremor and hind limb rigidity and have a decreased lifespan. Our lab has shown that exercise reduced Purkinje cell degeneration and delayed motor dysfunction, significantly increasing lifespan. Our study investigated how moderate exercise may mediate neuroprotection by analyzing brain-derived neurotrophic factor (BDNF) and its receptor TrkB. To link BDNF to exercise-induced neuroprotection, mutant and normal rats were infused with the TrkB antagonist K252a or vehicle into the third ventricle. During infusion, rats were subjected to moderate exercise regimens on a treadmill. Exercised mutants receiving K252a exhibited a 21.4% loss in Purkinje cells compared to their controls. Cerebellar TrkB expression was evaluated using non-drug-treated mutants subjected to various treadmill running regimens. Running animals expressed three times more TrkB than sedentary animals. BDNF was quantified via Sandwich ELISA, and cerebellar expression was found to be 26.6% greater in mutant rats on 7-day treadmill exercise regimen compared to 30 days of treadmill exercise. These results suggest that BDNF is involved in mediating exercise-induced neuroprotection. PMID:25710032

  6. Biphasic Response of Ciprofloxacin in Human Fibroblast Cell Cultures

    PubMed Central

    Hincal, Filiz; Gürbay, Aylin; Favier, Alain

    2003-01-01

    To investigate the possibility of the involvement of an oxidative stress induction in the mechanism of the cytotoxic effect of quinolone antibiotics, we examined the viability of human fibroblast cells exposed to ciprofloxacin (CPFX), and measured the levels of lipid peroxidation (LP), glutathione (GSH), and the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPX). The data showed that the effect of CPFX on the viability of cells, as determined by neutral red uptake assay, was time-dependent, and the dose-response relation was biphasic. Cytotoxicity was not observed in the concentration range 5–150 mg/l CPFX when the cells were incubated for 24 h. In contrast, lower concentrations (5 and 12.5 mg/l) of CPFX increased the cell growth in all incubation periods tested. Marked decreases in the viability of fibroblasts were observed at concentrations 50 and 75 mg/l, and ≥50 mg/l, following 48 and 72 h exposure, respectively (p < 0.05). However, when the cells were exposed to > 75 mg/l CPFX for 48 h, no cytotoxicity was observed. By exposing fibroblast cultures to 75 mg/l CPFX for 48 h, an induction of LP enhancement and a marked decrease in intracellular GSH were observed. Vitamin E pretreatment of the cells lowered the level of LP, increased the total GSH content, and provided significant protection against CPFX-induced cytotoxicity. The biphasic effect of CPFX possibly resulted from the complex dose-dependent relationships between reactive oxygen species (ROS), cell proliferation, and cell viability. It was previously reported, in fact, for several cell models that ROS exert a biphasic effect on cell growth. Furthermore, cultured fibroblasts release their own free radicals, and the inhibition of endogenous ROS inhibits the fibroblast cell proliferation, whereas the effect of exogenous ROS is biphasic. PMID:19330132

  7. Avenanthramide supplementation attenuates exercise-induced inflammation in postmenopausal women.

    PubMed

    Koenig, Ryan; Dickman, Jonathan R; Kang, Chounghun; Zhang, Tianou; Chu, Yi-Fang; Ji, Li Li

    2014-01-01

    During aging, chronic systemic inflammation increases in prevalence and antioxidant balance shifts in favor of oxidant generation. Avenanthramide (AVA) is a group of oat phenolics that have shown anti-inflammatory and antioxidant capability. The present study investigated whether dietary supplementation of avenanthramides (AVA) in oats would increase antioxidant protection and reduce inflammation after a bout of downhill walking (DW) in postmenopausal women. Women at age of 50-80 years (N = 16) were randomly divided into two groups in a double-blinded fashion, receiving two cookies made of oat flour providing 9.2 mg AVA or 0.4 mg AVA (control, C) each day for 8 weeks. Before and after the dietary regimen, each group of subjects walked downhill on a treadmill (-9% grade) for 4 bouts of 15 minutes at a speed of 4.0 km/h with 5 minutes rest between sessions. Blood samples were collected at rest, 24 h post-DW, and 48 h post-DW pre- and post-supplementation. Both DW sessions increased plasma creatine kinase activity (P < 0.05). Before supplementation, in vitro neutrophil respiratory burst (NRB) activity was increased at 24 h post-DW (P < 0.05) and C-reactive protein (CRP) was increased 48 h post-DW (P < 0.05). AVA supplementation decreased DW-induced NRB at 24 h (P < 0.05) and CRP level 48 h (P < 0.05). Plasma interleukin (IL)-1β concentration and mononuclear cell nuclear factor (NF) κB binding were suppressed at rest and during post-DW period in AVA but not C group (P < 0.05). Plasma total antioxidant capacity (P < 0.05) and erythrocyte superoxide dismutase activity were increased in AVA vs. C (P < 0.05), whereas glutathione redox status was elevated 48 h post-DW but not affected by AVA. Thus, chronic AVA supplementation decreased systemic and DW-induced inflammation and increased blood-borne antioxidant defense in postmenopausal women. PMID:24645793

  8. Avenanthramide supplementation attenuates exercise-induced inflammation in postmenopausal women

    PubMed Central

    2014-01-01

    During aging, chronic systemic inflammation increases in prevalence and antioxidant balance shifts in favor of oxidant generation. Avenanthramide (AVA) is a group of oat phenolics that have shown anti-inflammatory and antioxidant capability. The present study investigated whether dietary supplementation of avenanthramides (AVA) in oats would increase antioxidant protection and reduce inflammation after a bout of downhill walking (DW) in postmenopausal women. Women at age of 50–80 years (N = 16) were randomly divided into two groups in a double-blinded fashion, receiving two cookies made of oat flour providing 9.2 mg AVA or 0.4 mg AVA (control, C) each day for 8 weeks. Before and after the dietary regimen, each group of subjects walked downhill on a treadmill (−9% grade) for 4 bouts of 15 minutes at a speed of 4.0 km/h with 5 minutes rest between sessions. Blood samples were collected at rest, 24 h post-DW, and 48 h post-DW pre- and post-supplementation. Both DW sessions increased plasma creatine kinase activity (P < 0.05). Before supplementation, in vitro neutrophil respiratory burst (NRB) activity was increased at 24 h post-DW (P < 0.05) and C-reactive protein (CRP) was increased 48 h post-DW (P < 0.05). AVA supplementation decreased DW-induced NRB at 24 h (P < 0.05) and CRP level 48 h (P < 0.05). Plasma interleukin (IL)-1β concentration and mononuclear cell nuclear factor (NF) κB binding were suppressed at rest and during post-DW period in AVA but not C group (P < 0.05). Plasma total antioxidant capacity (P < 0.05) and erythrocyte superoxide dismutase activity were increased in AVA vs. C (P < 0.05), whereas glutathione redox status was elevated 48 h post-DW but not affected by AVA. Thus, chronic AVA supplementation decreased systemic and DW-induced inflammation and increased blood-borne antioxidant defense in postmenopausal women. PMID:24645793

  9. Biphasic Janus particles with nanoscale anisotropy

    NASA Astrophysics Data System (ADS)

    Roh, Kyung-Ho; Martin, David C.; Lahann, Joerg

    2005-10-01

    Advances in the field of nanotechnology have fuelled the vision of future devices spawned from tiny functional components that are able to assemble according to a master blueprint. In this concept, the controlled distribution of matter or `patchiness' is important for creating anisotropic building blocks and introduces an extra design parameter - beyond size and shape. Although the reliable and efficient fabrication of building blocks with controllable material distributions will be of interest for many applications in research and technology, their synthesis has been addressed only in a few specialized cases. Here we show the design and synthesis of polymer-based particles with two distinct phases. The biphasic geometry of these Janus particles is induced by the simultaneous electrohydrodynamic jetting of parallel polymer solutions under the influence of an electrical field. The individual phases can be independently loaded with biomolecules or selectively modified with model ligands, as confirmed by confocal microscopy and transmission electron microscopy. The fact that the spatial distribution of matter can be controlled at such small length scales will provide access to unknown anisotropic materials. This type of nanocolloid may enable the design of multicomponent carriers for drug delivery, molecular imaging or guided self-assembly.

  10. Effects of the consumption of caffeinated and decaffeinated instant coffee beverages on oxidative stress induced by strenuous exercise in rats.

    PubMed

    Viana, André Luiz Machado; Fonseca, Miriam das Dores Mendes; Meireles, Elisson Lamin Jerônimo; Duarte, Stella Maris da Silveira; Rodrigues, Maria Rita; Paula, Fernanda Borges de Araujo

    2012-03-01

    Many authors attribute the antioxidant activity of brewed coffee to its caffeine content. In addition, caffeine intake has been associated with increased performance during physical exercise. This study analyzed the in vivo effects of drinking caffeinated and decaffeinated instant coffee (8%, w/v) on oxidative stress and antioxidant enzyme activity in the anterior tibialis muscles of rats subjected to intense exercise. It was observed that exercise induced lipid peroxidation (estimated using malondialdehyde) and protein oxidation (evaluated by determining the formation of carbonyl groups) in the muscle (P < 0.05). Decaffeinated instant coffee and caffeine solution did not exhibit antioxidant activity in vivo. Caffeinated instant coffee beverage intake did not induce changes in superoxide dismutase and glutathione peroxidase activities but was able to diminish lipid and protein oxidation in the anterior tibialis muscles of rats after exercise (P < 0.05), contributing to a reduction in the oxidative stress triggered by exercise. PMID:22173821

  11. Exercise-induced metabolic fluctuations influence AMPK, p38-MAPK and CaMKII phosphorylation in human skeletal muscle.

    PubMed

    Combes, Adrien; Dekerle, Jeanne; Webborn, Nick; Watt, Peter; Bougault, Valérie; Daussin, Frédéric N

    2015-09-01

    During transition from rest to exercise, metabolic reaction rates increase substantially to sustain intracellular ATP use. These metabolic demands activate several kinases that initiate signal transduction pathways which modulate transcriptional regulation of mitochondrial biogenesis. The purpose of this study was to determine whether metabolic fluctuations per se affect the signaling cascades known to regulate peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α). On two separate occasions, nine men performed a continuous (30-min) and an intermittent exercise (30 × 1-min intervals separated by 1-min of recovery) at 70% of V˙O2peak. Skeletal muscle biopsies from the vastus lateralis were taken at rest and at +0 h and +3 h after each exercise. Metabolic fluctuations that correspond to exercise-induced variation in metabolic rates were determined by analysis of VO2 responses. During intermittent exercise metabolic fluctuations were 2.8-fold higher despite identical total work done to continuous exercise (317 ± 41 vs. 312 ± 56 kJ after intermittent and continuous exercise, respectively). Increased phosphorylation of AMP-activated protein kinase (AMPK) (~2.9-fold, P < 0.01), calcium/calmodulin-dependent protein kinase II (CaMKII) (~2.7-fold, P < 0.01) and p38-mitogen-activated protein kinase (MAPK) (~4.2-fold, P < 0.01) occurred immediately in both exercises and to a greater extent after the intermittent exercise (condition x time interaction, P < 0.05). A single bout of intermittent exercise induces a greater activation of these signaling pathways regulating PGC-1α when compared to a single bout of continuous exercise of matched work and intensity. Chronic adaptations to exercise on mitochondria biogenesis are yet to be investigated. PMID:26359238

  12. Dynamic changes in dna methylation status in peripheral blood Mononuclear cells following an acute bout of exercise: Potential impact of exercise-induced elevations in interleukin-6 concentration.

    PubMed

    Robson-Ansley, P J; Saini, A; Toms, C; Ansley, L; Walshe, I H; Nimmo, M A; Curtin, J A

    2014-01-01

    The aim of the present study was to examine the relationship between interleukin (IL)-6 concentrations and DNA methylation in the peripheral blood mononuclear cells (PBMCs) of trained runners after a bout of prolonged, strenuous exercise. Eight healthy trained males completed a treadmill run at 60% vVO(2max) for 120 min followed by a 5-km time trial in a fasted condition. Whole blood samples were taken prior to, immediately before and 24 h following exercise. From these samples, PBMCs were isolated for analysis and plasma IL-6 concentrations were measured. The methylation status of DNA extracted from PBMCs was analysed using the Illumina 27k methylation beadchip platform. Global DNA methylation status was unaltered immediately and up to 24 hours following a bout of prolonged exercise in comparison to pre-exercise. Despite no change in global DNA methylation, plasma IL-6 concentrations were significantly related to the DNA methylation status of 11 genes. Our study demonstrates that the methylome is stable, while discovering a novel link between exercise-induced increases in circulating IL-6 and the DNA methylation status of 11 individual genes. Based on our preliminary findings, the mechanisms by which changes in plasma IL-6 concentrations and DNA methylation in response to exercise interact require further study. PMID:25316129

  13. The Angiotensin Converting Enzyme Insertion/Deletion Polymorphism Modifies Exercise-Induced Muscle Metabolism

    PubMed Central

    Vaughan, David; Brogioli, Michael; Maier, Thomas; White, Andy; Waldron, Sarah; Rittweger, Jörn; Toigo, Marco; Wettstein, Jessica; Laczko, Endre; Flück, Martin

    2016-01-01

    Objective A silencer region (I-allele) within intron 16 of the gene for the regulator of vascular perfusion, angiotensin-converting enzyme (ACE), is implicated in phenotypic variation of aerobic fitness and the development of type II diabetes. We hypothesised that the reportedly lower aerobic performance in non-carriers compared to carriers of the ACE I-allele, i.e. ACE-DD vs. ACE-ID/ACE-II genotype, is associated with alterations in activity-induced glucose metabolism and capillarisation in exercise muscle. Methods Fifty-three, not-specifically trained Caucasian men carried out a one-legged bout of cycling exercise to exhaustion and/or participated in a marathon, the aim being to identify and validate genotype effects on exercise metabolism. Respiratory exchange ratio (RER), serum glucose and lipid concentration, glycogen, and metabolite content in vastus lateralis muscle based on ultra-performance lipid chromatography-mass spectrometry (UPLC-MS), were assessed before and after the cycling exercise in thirty-three participants. Serum metabolites were measured in forty subjects that completed the marathon. Genotype effects were assessed post-hoc. Results Cycling exercise reduced muscle glycogen concentration and this tended to be affected by the ACE I-allele (p = 0.09). The ACE-DD genotype showed a lower maximal RER and a selective increase in serum glucose concentration after exercise compared to ACE-ID and ACE-II genotypes (+24% vs. +2% and –3%, respectively). Major metabolites of mitochondrial metabolism (i.e. phosphoenol pyruvate, nicotinamide adenine dinucleotide phosphate, L-Aspartic acid, glutathione) were selectively affected in vastus lateralis muscle by exercise in the ACE-DD genotype. Capillary-to-fibre ratio was 24%-lower in the ACE-DD genotype. Individuals with the ACE-DD genotype demonstrated an abnormal increase in serum glucose to 7.7 mM after the marathon. Conclusion The observations imply a genetically modulated role for ACE in control of

  14. The calcineurin antagonist RCAN1-4 is induced by exhaustive exercise in rat skeletal muscle.

    PubMed

    Emrani, Ramin; Rébillard, Amélie; Lefeuvre, Luz; Gratas-Delamarche, Arlette; Davies, Kelvin J A; Cillard, Josiane

    2015-10-01

    The aim of this work was to study the regulation of the calcineurin antagonist regulator of calcineurin 1 (RCAN1) in rat skeletal muscles after exhaustive physical exercise, which is a physiological modulator of oxidative stress. Three skeletal muscles, namely extensor digitorum longus (EDL), gastrocnemius, and soleus, were investigated. Exhaustive exercise increased RCAN1-4 protein levels in EDL and gastrocnemius, but not in soleus. Protein oxidation as an index of oxidative stress was increased in EDL and gastrocnemius, but remained unchanged in soleus. However, lipid peroxidation was increased in all three muscles. CuZnSOD and catalase protein levels were increased at 3 h postexercise in soleus, whereas they remained unchanged in EDL and gastrocnemius. Calcineurin enzymatic activity declined in EDL and gastrocnemius but not in soleus, and its protein expression was decreased in all three muscles. The level of PGC1-α protein remained unchanged, whereas the protein expression of the transcription factor NFATc4 was decreased in all three muscles. Adiponectin expression was increased in all three muscles. RCAN1-4 expression in EDL and gastrocnemius muscles was augmented by the oxidative stress generated from exhaustive exercise. We propose that increased RCAN1-4 expression and the signal transduction pathways it regulates represent important components of the physiological adaptation to exercise-induced oxidative stress. PMID:26122706

  15. Susceptibility to Exercise-Induced Muscle Damage: a Cluster Analysis with a Large Sample.

    PubMed

    Damas, F; Nosaka, K; Libardi, C A; Chen, T C; Ugrinowitsch, C

    2016-07-01

    We investigated the responses of indirect markers of exercise-induced muscle damage (EIMD) among a large number of young men (N=286) stratified in clusters based on the largest decrease in maximal voluntary contraction torque (MVC) after an unaccustomed maximal eccentric exercise bout of the elbow flexors. Changes in MVC, muscle soreness (SOR), creatine kinase (CK) activity, range of motion (ROM) and upper-arm circumference (CIR) before and for several days after exercise were compared between 3 clusters established based on MVC decrease (low, moderate, and high responders; LR, MR and HR). Participants were allocated to LR (n=61), MR (n=152) and HR (n=73) clusters, which depicted significantly different cluster centers of 82%, 61% and 42% of baseline MVC, respectively. Once stratified by MVC decrease, all muscle damage markers were significantly different between clusters following the same pattern: small changes for LR, larger changes for MR, and the largest changes for HR. Stratification of individuals based on the magnitude of MVC decrease post-exercise greatly increases the precision in estimating changes in EIMD by proxy markers such as SOR, CK activity, ROM and CIR. This indicates that the most commonly used markers are valid and MVC orchestrates their responses, consolidating the role of MVC as the best EIMD indirect marker. PMID:27116346

  16. Effect of dehydroepiandrosterone administration on recovery from mix-type exercise training-induced muscle damage.

    PubMed

    Liao, Yi-Hung; Liao, Kun-Fu; Kao, Chung-Lan; Chen, Chung-Yu; Huang, Chih-Yang; Chang, Wei-Hsiang; Ivy, John L; Bernard, Jeffrey R; Lee, Shin-Da; Kuo, Chia-Hua

    2013-01-01

    This study aimed to determine the role of DHEA-S in coping against the exercise training mixing aerobic and resistance components. During 5-day successive exercise training, 16 young male participants (19.2 ± 1.2 years) received either a placebo (flour capsule) or DHEA (100 mg/day) in a double-blinded and placebo-controlled design. Oral DHEA supplementation significantly increased circulating DHEA-S by 2.5-fold, but a protracted drop (~35 %) was observed from Day 3 during training. In the Placebo group, only a minimal DHEA-S reduction (~17 %) was observed. Changes in testosterone followed a similar pattern as DHEA-S. Muscle soreness was elevated significantly on Day 2 for both groups to a similar extent. Lower muscle soreness was observed in the DHEA-supplemented group on Day 3 and Day 6. In the Placebo group, training increased circulating creatine kinase (CK) levels by approximately ninefold, while only a threefold increase was observed in the DHEA-supplemented group. This mix-type exercise training improved glucose tolerance in both groups, while lowering the insulin response to the glucose challenge, but no difference between treatments was observed. Our results suggest that DHEA-S may play a role in protecting skeletal muscle from exercise training-induced muscle damage. PMID:22588361

  17. Voluntary Exercise Induces Astrocytic Structural Plasticity in the Globus Pallidus

    PubMed Central

    Tatsumi, Kouko; Okuda, Hiroaki; Morita-Takemura, Shoko; Tanaka, Tatsuhide; Isonishi, Ayami; Shinjo, Takeaki; Terada, Yuki; Wanaka, Akio

    2016-01-01

    Changes in astrocyte morphology are primarily attributed to the fine processes where intimate connections with neurons form the tripartite synapse and participate in neurotransmission. Recent evidence has shown that neurotransmission induces dynamic synaptic remodeling, suggesting that astrocytic fine processes may adapt their morphologies to the activity in their environment. To illustrate such a neuron-glia relationship in morphological detail, we employed a double transgenic Olig2CreER/WT; ROSA26-GAP43-EGFP mice, in which Olig2-lineage cells can be visualized and traced with membrane-targeted GFP. Although Olig2-lineage cells in the adult brain usually become mature oligodendrocytes or oligodendrocyte precursor cells with NG2-proteoglycan expression, we found a population of Olig2-lineage astrocytes with bushy morphology in several brain regions. The globus pallidus (GP) preferentially contains Olig2-lineage astrocytes. Since the GP exerts pivotal motor functions in the indirect pathway of the basal ganglionic circuit, we subjected the double transgenic mice to voluntary wheel running to activate the GP and examined morphological changes of Olig2-lineage astrocytes at both the light and electron microscopic levels. The double transgenic mice were divided into three groups: control group mice were kept in a cage with a locked running wheel for 3 weeks, Runner group were allowed free access to a running wheel for 3 weeks, and the Runner-Rest group took a sedentary 3-week rest after a 3-week running period. GFP immunofluorescence analysis and immunoelectron microscopy revealed that astrocytic fine processes elaborated complex arborization in the Runner mice, and reverted to simple morphology comparable to that of the Control group in the Runner-Rest group. Our results indicated that the fine processes of the Olig2-lineage astrocytes underwent plastic changes that correlated with overall running activities, suggesting that they actively participate in motor

  18. Voluntary Exercise Induces Astrocytic Structural Plasticity in the Globus Pallidus.

    PubMed

    Tatsumi, Kouko; Okuda, Hiroaki; Morita-Takemura, Shoko; Tanaka, Tatsuhide; Isonishi, Ayami; Shinjo, Takeaki; Terada, Yuki; Wanaka, Akio

    2016-01-01

    Changes in astrocyte morphology are primarily attributed to the fine processes where intimate connections with neurons form the tripartite synapse and participate in neurotransmission. Recent evidence has shown that neurotransmission induces dynamic synaptic remodeling, suggesting that astrocytic fine processes may adapt their morphologies to the activity in their environment. To illustrate such a neuron-glia relationship in morphological detail, we employed a double transgenic Olig2(CreER/WT); ROSA26-GAP43-EGFP mice, in which Olig2-lineage cells can be visualized and traced with membrane-targeted GFP. Although Olig2-lineage cells in the adult brain usually become mature oligodendrocytes or oligodendrocyte precursor cells with NG2-proteoglycan expression, we found a population of Olig2-lineage astrocytes with bushy morphology in several brain regions. The globus pallidus (GP) preferentially contains Olig2-lineage astrocytes. Since the GP exerts pivotal motor functions in the indirect pathway of the basal ganglionic circuit, we subjected the double transgenic mice to voluntary wheel running to activate the GP and examined morphological changes of Olig2-lineage astrocytes at both the light and electron microscopic levels. The double transgenic mice were divided into three groups: control group mice were kept in a cage with a locked running wheel for 3 weeks, Runner group were allowed free access to a running wheel for 3 weeks, and the Runner-Rest group took a sedentary 3-week rest after a 3-week running period. GFP immunofluorescence analysis and immunoelectron microscopy revealed that astrocytic fine processes elaborated complex arborization in the Runner mice, and reverted to simple morphology comparable to that of the Control group in the Runner-Rest group. Our results indicated that the fine processes of the Olig2-lineage astrocytes underwent plastic changes that correlated with overall running activities, suggesting that they actively participate in motor

  19. Abnormal expression of key genes and proteins in the canonical Wnt/β-catenin pathway of articular cartilage in a rat model of exercise-induced osteoarthritis

    PubMed Central

    LIU, SHEN-SHEN; ZHOU, PU; ZHANG, YANQIU

    2016-01-01

    To investigate the molecular pathogenesis of the canonical Wnt/β-catenin pathway in exercise-induced osteoarthritis (OA), 30 male healthy Sprague Dawley rats were divided into three groups (control, normal exercise-induced OA and injured exercise-induced OA groups) in order to establish the exercise-induced OA rat model. The mRNA and protein expression levels of Runx-2, BMP-2, Ctnnb1, Sox-9, collagen II, Mmp-13, Wnt-3a and β-catenin in chon-drocytes were detected by reverse transcription-quantitative polymerase chain reaction, western blotting and immunohistochemical staining. The mRNA levels of Runx-2, BMP-2 and Ctnnb1 were upregulated in the normal exercise-induced OA and injured exercise-induced OA groups; while Runx-2 and BMP-2 were upregulated in the injured exercise-induced OA group when compared with the normal exercise-induced OA group. The protein levels of Mmp-13, Wnt-3a and β-catenin were increased and collagen II was reduced in the normal exercise-induced OA and injured exercise-induced OA groups. Ctnnb1, Wnt-3a and β-catenin, which are key genes and proteins in the canonical Wnt/β-catenin pathway, were abnormally expressed in chondrocytes of the exercise-induced OA rat model. Ctnnb1, β-catenin and Wnt-3a were suggested to participate in the pathogenesis of exercise-induced OA by abnormally activating the Wnt/β-catenin pathway during physical exercise due to excessive pressure. The results of the present study may provide an improved understanding of the pathogenesis of exercise-induced OA. PMID:26794964

  20. Exercise Prevents Memory Impairment Induced by Arsenic Exposure in Mice: Implication of Hippocampal BDNF and CREB

    PubMed Central

    Yu, Zi-Jiang; Yu, Yan; Xiao, Chao-Lun; Kang, Chao-Sheng; Ge, Guo; Linghu, Yan; Zhu, Jun-De; Li, Yu-Mei; Li, Qiang-Ming; Luo, Shi-Peng; Yang, Dang; Li, Lin; Zhang, Wen-Yan; Tian, Guang

    2015-01-01

    High concentrations of arsenic, which can be occasionally found in drinking water, have been recognized as a global health problem. Exposure to arsenic can disrupt spatial memory; however, the underlying mechanism remains unclear. In the present study, we tested whether exercise could interfere with the effect of arsenic exposure on the long-term memory (LTM) of object recognition in mice. Arsenic (0, 1, 3, and 10 mg/ kg, i.g.) was administered daily for 12 weeks. We found that arsenic at dosages of 1, 3, and 10 mg/kg decreased body weight and increased the arsenic content in the brain. The object recognition LTM (tested 24 h after training) was disrupted by 3 mg/ kg and 10 mg/ kg, but not 1 mg/ kg arsenic exposure. Swimming exercise also prevented LTM impairment induced by 3 mg/ kg, but not with 10 mg/ kg, of arsenic exposure. The expression of brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP-response element binding protein (pCREB) in the CA1 and dentate gyrus areas (DG) of the dorsal hippocampus were decreased by 3 mg/ kg and 10 mg/ kg, but not by 1 mg/ kg, of arsenic exposure. The decrease in BDNF and pCREB in the CA1 and DG induced by 3 mg/ kg, but not 10 mg/ kg, of arsenic exposure were prevented by swimming exercise. Arsenic exposure did not affect the total CREB expression in the CA1 or DG. Taken together, these results indicated that swimming exercise prevented the impairment of object recognition LTM induced by arsenic exposure, which may be mediated by BDNF and CREB in the dorsal hippocampus. PMID:26368803

  1. Effects of allopurinol on exercise-induced muscle damage: new therapeutic approaches?

    PubMed

    Sanchis-Gomar, F; Pareja-Galeano, H; Perez-Quilis, C; Santos-Lozano, A; Fiuza-Luces, C; Garatachea, N; Lippi, G; Lucia, A

    2015-01-01

    Intensive muscular activity can trigger oxidative stress, and free radicals may hence be generated by working skeletal muscle. The role of the enzyme xanthine oxidase as a generating source of free radicals is well documented and therefore is involved in the skeletal muscle damage as well as in the potential transient cardiovascular damage induced by high-intensity physical exercise. Allopurinol is a purine hypoxanthine-based structural analog and a well-known inhibitor of xanthine oxidase. The administration of the xanthine oxidase inhibitor allopurinol may hence be regarded as promising, safe, and an economic strategy to decrease transient skeletal muscle damage (as well as heart damage, when occurring) in top-level athletes when administered before a competition or a particularly high-intensity training session. Although continuous administration of allopurinol in high-level athletes is not recommended due to its possible role in hampering training-induced adaptations, the drug might be useful in non-athletes. Exertional rhabdomyolysis is the most common form of rhabdomyolysis and affects individuals participating in a type of intense exercise to which they are not accustomed. This condition can cause exercise-related myoglobinuria, thus increasing the risk of acute renal failure and is also associated with sickle cell trait. In this manuscript, we have reviewed the recent evidence about the effects of allopurinol on exercise-induced muscle damage. More research is needed to determine whether allopurinol may be useful for preventing not only exertional rhabdomyolysis and acute renal damage but also skeletal muscle wasting in critical illness as well as in immobilized, bedridden, sarcopenic or cachectic patients. PMID:25181966

  2. A combination of exercise and capsinoid supplementation additively suppresses diet-induced obesity by increasing energy expenditure in mice.

    PubMed

    Ohyama, Kana; Nogusa, Yoshihito; Suzuki, Katsuya; Shinoda, Kosaku; Kajimura, Shingo; Bannai, Makoto

    2015-02-15

    Exercise effectively prevents the development of obesity and obesity-related diseases such as type 2 diabetes. Capsinoids (CSNs) are capsaicin analogs found in a nonpungent pepper that increase whole body energy expenditure. Although both exercise and CSNs have antiobesity functions, the effectiveness of exercise with CSN supplementation has not yet been investigated. Here, we examined whether the beneficial effects of exercise could be further enhanced by CSN supplementation in mice. Mice were randomly assigned to four groups: 1) high-fat diet (HFD, Control), 2) HFD containing 0.3% CSNs, 3) HFD with voluntary running wheel exercise (Exercise), and 4) HFD containing 0.3% CSNs with voluntary running wheel exercise (Exercise + CSN). After 8 wk of ingestion, blood and tissues were collected and analyzed. Although CSNs significantly suppressed body weight gain under the HFD, CSN supplementation with exercise additively decreased body weight gain and fat accumulation and increased whole body energy expenditure compared with exercise alone. Exercise together with CSN supplementation robustly improved metabolic profiles, including the plasma cholesterol level. Furthermore, this combination significantly prevented diet-induced liver steatosis and decreased the size of adipocyte cells in white adipose tissue. Exercise and CSNs significantly increased cAMP levels and PKA activity in brown adipose tissue (BAT), indicating an increase of lipolysis. Moreover, they significantly activated both the oxidative phosphorylation gene program and fatty acid oxidation in skeletal muscle. These results indicate that CSNs efficiently promote the antiobesity effect of exercise, in part by increasing energy expenditure via the activation of fat oxidation in skeletal muscle and lipolysis in BAT. PMID:25516550

  3. Dysfunctional breathing and reaching one’s physiological limit as causes of exercise-induced dyspnoea

    PubMed Central

    Everard, Mark L.

    2016-01-01

    Key points Excessive exercise-induced shortness of breath is a common complaint. For some, exercise-induced bronchoconstriction is the primary cause and for a small minority there may be an alternative organic pathology. However for many, the cause will be simply reaching their physiological limit or be due to a functional form of dysfunctional breathing, neither of which require drug therapy. The physiological limit category includes deconditioned individuals, such as those who have been through intensive care and require rehabilitation, as well as the unfit and the fit competitive athlete who has reached their limit with both of these latter groups requiring explanation and advice. Dysfunctional breathing is an umbrella term for an alteration in the normal biomechanical patterns of breathing that result in intermittent or chronic symptoms, which may be respiratory and/or nonrespiratory. This alteration may be due to structural causes or, much more commonly, be functional as exemplified by thoracic pattern disordered breathing (PDB) and extrathoracic paradoxical vocal fold motion disorder (pVFMD). Careful history and examination together with spirometry may identify those likely to have PDB and/or pVFMD. Where there is doubt about aetiology, cardiopulmonary exercise testing may be required to identify the deconditioned, unfit or fit individual reaching their physiological limit and PDB, while continuous laryngoscopy during exercise is increasingly becoming the benchmark for assessing extrathoracic causes. Accurate assessment and diagnosis can prevent excessive use of drug therapy and result in effective management of the cause of the individual’s complaint through cost-effective approaches such as reassurance, advice, breathing retraining and vocal exercises. This review provides an overview of the spectrum of conditions that can present as exercise-­induced breathlessness experienced by young subjects participating in sport and aims to promote understanding of

  4. The influence of ice slushy on voluntary contraction force following exercise-induced hyperthermia.

    PubMed

    Burdon, Catriona A; Easthope, Christopher S; Johnson, Nathan A; Chapman, Phillip G; O'Connor, Helen

    2014-07-01

    This study aimed to investigate the effect of exercise-induced hyperthermia on central fatigue and force decline in exercised and nonexercised muscles and whether ingestion of ice slushy (ICE) ameliorates fatigue. Eight participants (5 males, 3 females) completed 45 s maximal voluntary isometric contractions (MVIC) with elbow flexors and knee extensors at baseline and following an exercise-induced rectal temperature (Trec) of 39.3 ± 0.2 °C. Percutaneous electrical muscle stimulation was superimposed at 15, 30 and 44 s during MVICs to assess muscle activation. To increase Trec to 39.3 °C, participants cycled at 60% maximum power output for 42 ± 11 min in 40 °C and 50% relative humidity. Immediately prior to each MVIC, participants consumed 50 g of ICE (-1 °C) or thermoneutral drink (38 °C, CON) made from 7.4% carbohydrate beverage. Participants consumed water (19 °C) during exercise to prevent hypohydration. Voluntary muscle force production and activation in both muscle groups were unchanged at Trec 39.3 °C with ICE (knee extensors: 209 ± 152 N) versus CON (knee extensors: 255 ± 157 N, p = 0.19). At Trec 39.3 °C, quadriceps mean force (232 ± 151 N) decreased versus baseline (302 ± 180 N, p < 0.001) and mean voluntary activation was also decreased (by 15% ± 11%, p < 0.001). Elbow flexor mean force decreased from 179 ± 67 N to 148 ± 65 N when Trec was increased to 39.3 °C (p < 0.001) but mean voluntary activation was not reduced at 39.3 °C (5% ± 25%, p = 0.79). After exercise-induced hyperthermia, ICE had no effect on voluntary activation or force production; however, both were reduced from baseline in the exercised muscle group. Peripheral fatigue was greater than the central component and limited the ability of an intervention designed to alter central fatigue. PMID:24971678

  5. Effects of ginsenosides-Rb1 on exercise-induced oxidative stress in forced swimming mice

    PubMed Central

    Qi, Bo; Zhang, Lan; Zhang, Zhiqun; Ouyang, Jiangqiong; Huang, Hui

    2014-01-01

    Background: The fleshy root of Panax ginseng C.A. Meyer (ginseng) is one of the most well-known and valued herbs in traditional Chinese medicine. Ginsenosides are considered mainly responsible for the pharmacological activities of ginseng. The purpose of this study was to investigate the effects of ginsenoside-Rb1 (G-Rb1) on swimming exercise-induced oxidative stress in male mice. Materials and Methods: A total of 48 animals were randomly divided into four groups, with twelve mice in each group. The first, second and third groups were designed as G-Rb1 treatment groups, got 25, 50 and 100 mg/kg bodyweight of G-Rb1, respectively. The fourth group was designed as the control group, got physiologic saline. The mice were intragastrically administered once daily for 4 weeks. The weight-loaded forced swimming test was conducted on the final day of experimentation. Then the exhaustive swimming time, blood lactate, serum creatine kinase (CK), malondialdehyde (MDA) and antioxidant enzymes in liver of mice were measured. Results: The results showed that G-Rb1 could prolong the exhaustive swimming time and improve exercise endurance capacity of mice, as well as accelerate the clearance of blood lactate and decrease serum CK activities. Meanwhile, G-Rb1 could decrease MDA contents and increase superoxide dismutase, catalase, glutathione peroxidase activities in liver of mice. Conclusions: The study suggested that G-Rb1 possessed protective effects on swimming exercise-induced oxidative stress in mice. PMID:25422546

  6. Time course of exercise-induced bronchoconstriction in asthmatics exposed to sulfur dioxide

    SciTech Connect

    Hackney, J.D.; Linn, W.S.; Bailey, R.M.; Spier, C.E.; Valencia, L.M.

    1984-08-01

    Young adult asthmatic volunteers (N = 17) were exposed to 0.75 ppM sulfur dioxide (SO/sub 2/) for 3-hr periods, exercising vigorously for the first 10 min and resting thereafter. Specific airway resistance (SR/sub aw/) and symptoms were recorded preexposure, immediately postexercise, and after 1, 2, and 3 hr of exposure. Symptoms and SR/sub aw/ were significantly increased after exercise, relative to preexposure measurements. Group mean SR/sub aw/ and symptom increases were no longer significant at 1 hr. In a few individuals, effects may have persisted for 2 hr or more. On separate occasions, comparable exposures were conducted, and forced expiratory spirometry was performed preexposure and postexercise, in addition to the other tests. Inclusion of spirometry did no significantly affect the other results. Spirometry and SR/sub aw/ showed nearly equal significance in changes postexercise. Thus, in general, asthmatics bronchoconstriction induced by exercise in SO/sub 2/ seems to reverse quickly with rest, even if SO/sub 2/ exposure continues. Spirometry may be useful for studying pollution-induced bronchoconstriction when SR/sub aw/ measurements are impractical.

  7. Spontaneous Pneumomediastinum in Non-Asthmatic Children with Exercise-Induced Bronchoconstriction

    PubMed Central

    Anantasit, Nattachai; Manuyakorn, Wiparat; Anantasit, Nualnapa; Choong, Karen; Preuthipan, Aroonwan

    2015-01-01

    Case series Patient: Male, 11 • Male, 15 Final Diagnosis: Spontaneous pneumomediastinum Symptoms: — Medication: — Clinical Procedure: None Specialty: Pediatrics and Neonatology Objective: Unusual clinical course Background: Subcutaneous emphysema can result from rupture of the respiratory or gastrointestinal systems, commonly occurring after trauma or surgery, as well as from rupture of alveoli as pneumothorax or pneumomediastinum. Spontaneous pneumomediastinum with subcutaneous emphysema is rare in children without chest or neck trauma. Here, we report 2 cases of spontaneous pneumomediastinum with exercise-induced bronchoconstriction. Case Report: The first case is an 11-year-old boy who presented with neck pain after vigorous exercise. Radiography showed pneumomediastinum. The second case is a 15-year-old boy who presented with pleuritic chest pain and respiratory failure requiring intubation. We extensively investigated the possible causes of pneumomediastinum. Both patients had no history of trauma or asthma, and were diagnosed with exercise-induced bronchoconstriction. They were discharged after conservative treatment, without complication. Conclusions: Early recognition and investigation of serious conditions should be promptly done in spontaneous pneumomediastinum patients. Conservative treatment, extensive investigations of predisposing factors, and treatment are important. PMID:26394070

  8. [A case of food-dependent exercise-induced anaphylaxis caused by ingestion of orange].

    PubMed

    Ono, Rintaro; Motomura, Chikako; Takamatsu, Nobue; Kondo, Yasuto; Akamine, Yuko; Matsuzaki, Hiroshi; Murakami, Yoko; Amimoto, Yuko; Taba, Naohiko; Honjyo, Satoshi; Shibata, Rumiko; Odajima, Hiroshi

    2015-02-01

    The patient was a 10-year-old girl who presented with a history of anaphylactic episodes on three occasions, that developed in association with exercise after she ate citrus fruit. She underwent tolerance tests, as food-dependent exercise-induced anaphylaxis (FDEIA) induced by citrus fruit was suspected. The result of the test for the combination of intake of oranges and exercise was negative. The patient presented with swollen eyelid and wheezing following combined intake of orange and aspirin, based on which she was diagnosed as having FDEIA. Many patients developing an allergic reaction to fruit are diagnosed as having oral allergy syndrome (OAS), and only few cases of FDEIA are reported. Immunoblot tests revealed antigens of 9 kDa, 39 kDa and 53 kDa in this patient, and an inhibition study with oranges revealed that the 39 kDa and 53 kDa antigens were probably antigen-specific allergens. Although the studied patient showed a strongly positive result for IgE antibodies specifically directed at cedar pollen, no common antigenicity with cedar pollen could be recognized. The final diagnosis was a type of FDEIA caused by 39 kDa and 53 kDa proteins, which are different from antigens previously identified in patients with citrus fruits allergy. It should be the first report of such a case. PMID:25924908

  9. Restoration of fluid balance after exercise-induced dehydration: effects of alcohol consumption.

    PubMed

    Shirreffs, S M; Maughan, R J

    1997-10-01

    The effect of alcohol consumption on the restoration of fluid and electrolyte balance after exercise-induced dehydration [2.01 +/- 0.10% (SD) of body mass] was investigated. Drinks containing 0, 1, 2, and 4% alcohol were consumed over 60 min beginning 30 min after the end of exercise; a different beverage was consumed in each of four trials. The volume consumed (2,212 +/- 153 ml) was equivalent to 150% of body mass loss. Peak urine flow rate occurred later (P = 0.024) with the 4% beverage. The total volume of urine produced over the 6 h after rehydration, although not different between trials (P = 0.307), tended to increase as the quantity of alcohol ingested increased. The increase in blood (P = 0.013) and plasma (P = 0.050) volume with rehydration was slower when the 4% beverage was consumed and did not increase to values significantly greater than the dehydrated level (P = 0.013 and P = 0.050 for blood volume and plasma volume, respectively); generally, the increase was an inverse function of the quantity of alcohol consumed. These results suggest that alcohol has a negligible diuretic effect when consumed in dilute solution after a moderate level of hypohydration induced by exercise in the heat. There appears to be no difference in recovery from dehydration whether the rehydration beverage is alcohol free or contains up to 2% alcohol, but drinks containing 4% alcohol tend to delay the recovery process. PMID:9338423

  10. Food-Dependent Exercise-Induced Anaphylaxis: A Case Related to Chickpea Ingestion and Review

    PubMed Central

    2007-01-01

    Food-dependent exercise-induced anaphylaxis (FDEIA) is recognized as a distinct category of exercise-induced anaphylaxis (EIA) but is very likely underdiagnosed. This report describes a 41-year-old Indian woman who experienced two separate episodes of anaphylaxis while dancing after she had eaten chickpea-containing foods. The chickpea, a small legume, is a staple ingredient in culinary traditions from around the world, especially in India, the Middle East, and North Africa. Chickpea-containing dishes are also becoming more widespread in the Western world with the growing popularity of South Asian, Middle Eastern, and African cuisines. It is important to consider FDEIA in cases of unexplained anaphylaxis as reactions can occur several hours after ingesting the culprit food(s). Furthermore, no reaction occurs if a sensitized individual eats the culprit food(s) without exercising afterward; therefore, triggering foods can easily be overlooked. Current ideas on the pathophysiology, predisposing factors, workup, and treatment of FDEIA are also summarized here. PMID:20525119

  11. [Clinical courses of 18 cases with food-dependent exercise-induced anaphylaxis].

    PubMed

    Kano, H; Juji, F; Shibuya, N; Narita, M; Naritaka, S; Suko, M; Morita, Y; Iwata, T

    2000-06-01

    Eighteen cases (7 males and 11 females) of food-dependent exercise-induced anaphylaxis were observed for several years. The age of the patients at the first visit to our hospital ranged from 9 to 43 years (average 24.3 years). The offending foods were wheat in 9 cases, shrimp in 2 cases, shellfish in 1 case, fish in 1 case, and unknown foods in 5 cases. The inducing exercises were ball play games, running, riding a bicycle, swimming, kendo (Japanese fencing), walking, and so on. We advised these patients to avoid eating offending foods or taking exercises, or to take antiallergic medicine such as DSCG, and repirinast. We observed their clinical courses and laboratory data for 2 to 10 years. Only a few cases relapsed anaphylactoid reactions, but all cases have improved until now. In some cases, IgE RAST scores for wheat decreased. In other cases, the rate of histamine release on anti-IgE stimulation decreased after taking DSCG. PMID:10916885

  12. Vitamin E attenuates myocardial oxidative stress induced by DHEA in rested and exercised rats.

    PubMed

    Goldfarb, A H; McIntosh, M K; Boyer, B T

    1996-02-01

    Sixty-four male Sprague-Dawley rats were randomly assigned to one of eight treatment groups to determine whether vitamin E (VitE) could help protect the heart from oxidative stress induced by either dehydroepiandrosterone (DHEA) or exercise. Oxidative stress was indicated by lipid peroxidation [i.e., thiobarbituric acid-reactive substances (TBARS)] and two scavenger enzymes. VitE supplementation (250 IU VitE/kg of diet) was given to one-half of the rats. DHEA acetate (0.35 mol/kg body wt) was injected intraperitoneally to one-half of the animals while the others were injected with corn oil vehicle. All treatments lasted for 5 wk. Next, 32 rats were randomly assigned to run for 1 h on a motorized rodent treadmill at 21 m/min up a 12% grade and then were killed. The remaining rats were killed at rest. Exercise increased TBARS in heart independent of treatment (1.94 +/- 0.12 vs. 2.43 +/- 0.11 nmol/mg protein). VitE attenuated the amount of TBARS in heart when DHEA was given. DHEA significantly increased TBARS in heart. Total and selenium-dependent glutathione peroxidase activities in heart were unaffected by any treatment. DHEA increased catalase activity at rest. Exercise increased catalase activity (71.5 +/- 7.9 vs. 97.4 +/- 9.5 mu mol x min-1 x mg protein-1); however, when VitE was given, the response to exercise was attenuated (74.1 +/- 8.4 vs. 80.9 +/- 9.9 mu mol center dot min-1 x mg protein-1). These results suggest that aerobic exercise and DHEA are mild oxidative stressors on the heart and that VitE supplementation can be beneficial in attenuating these combined stressors on the heart. PMID:8929588

  13. Acute resistance exercise-induced IGF1 expression and subsequent GLUT4 translocation.

    PubMed

    Kido, Kohei; Ato, Satoru; Yokokawa, Takumi; Makanae, Yuhei; Sato, Koji; Fujita, Satoshi

    2016-08-01

    Acute aerobic exercise (AE) is a major physiological stimulus for skeletal muscle glucose uptake through activation of 5' AMP-activated protein kinase (AMPK). However, the regulation of glucose uptake by acute resistance exercise (RE) remains unclear. To investigate the intracellular regulation of glucose uptake after acute RE versus acute AE, male Sprague-Dawley rats were divided into three groups: RE, AE, or nonexercise control. After fasting for 12 h overnight, the right gastrocnemius muscle in the RE group was exercised at maximum isometric contraction via percutaneous electrical stimulation (3 × 10 sec, 5 sets). The AE group ran on a treadmill (25 m/min, 60 min). Muscle samples were taken 0, 1, and 3 h after completion of the exercises. AMPK, Ca(2+)/calmodulin-dependent protein kinase II, and TBC1D1 phosphorylation were increased immediately after both forms of exercise and returned to baseline levels by 3 h. Muscle IGF1 expression was increased by RE but not AE, and maintained until 3 h after RE Additionally, Akt and AS160 phosphorylation were sustained for 3 h after RE, whereas they returned to baseline levels by 3 h after AE Similarly, GLUT4 translocation remained elevated 3 h after RE, although it returned to the baseline level by 3 h after AE Overall, this study showed that AMPK/TBC1D1 and IGF1/Akt/AS160 signaling were enhanced by acute RE, and that GLUT4 translocation after acute RE was more prolonged than after acute AE These results suggest that acute RE-induced increases in intramuscular IGF1 expression might be a distinct regulator of GLUT4 translocation. PMID:27550988

  14. Exercise reward induces appetitive 50-kHz calls in rats.

    PubMed

    Heyse, Natalie C; Brenes, Juan C; Schwarting, Rainer K W

    2015-08-01

    Rats express affective states by visible behaviors (like approach or flight) and through different kinds of ultrasonic vocalizations (USV). 50-kHz calls are thought to reflect positive affective states since they occur during rewarding situations like social play or palatable food. However, the effects of voluntary exercise on USV have not been investigated yet, although such exercise can serve as reward. To this aim, we gave young adult rats restricted daily access to a runway maze, where they could interact with either a movable (experimental group) or locked wheel (sedentary group) for 14days and we tested USV in anticipation of and during subsequent running. We also studied inter-individual differences in running, and relationships with USV, and rat-typical trait measures. The results showed that the experimental rats had to be separated into "runners" and "pseudorunners" since only runners performed true running, whereas pseudorunners hardly entered the wheel and turned it only with their forelimbs. This outcome seems to be related to subject-dependent differences in responding to novelty and in reward sensitivity, as indicated by pertinent screening tests, which we had performed prior to the 14days of wheel access. In the runway, our experimental and control groups did not differ in visible anticipatory behavior, like approach. Yet, only runners and sedentary rats displayed an increasing but similar amount of anticipatory USV, which is suggestive of a state of incentive anticipation of the coming wheel access. During exercise, only runners increased USV, probably indicating a highly positive emotional state. To conclude, voluntary exercise provides a promising tool to induce 50-kHz USV during and in anticipation of exercise. When performing such studies, possible individual differences between subjects have to be taken into account, and the actual wheel performance should carefully be controlled. PMID:25872156

  15. Energy deficit after exercise augments lipid mobilization but does not contribute to the exercise-induced increase in insulin sensitivity

    PubMed Central

    Newsom, Sean A.; Schenk, Simon; Thomas, Kristin M.; Harber, Matthew P.; Knuth, Nicolas D.; Goldenberg, Naila

    2010-01-01

    The content of meals consumed after exercise can impact metabolic responses for hours and even days after the exercise session. The purpose of this study was to compare the effect of low dietary carbohydrate (CHO) vs. low energy intake in meals after exercise on insulin sensitivity and lipid metabolism the next day. Nine healthy men participated in four randomized trials. During the control trial (CON) subjects remained sedentary. During the other three trials, subjects exercised [65% peak oxygen consumption (V̇o2peak); cycle ergometer and treadmill exercise] until they expended ∼800 kcal. Dietary intake during CON and one exercise trial (BAL) was designed to provide sufficient energy and carbohydrate to maintain nutrient balance. In contrast, the diets after the other two exercise trials were low in either CHO (LOW-CHO) or energy (LOW-EN). The morning after exercise we obtained a muscle biopsy, assessed insulin sensitivity (Si; intravenous glucose tolerance test) and measured lipid kinetics (isotope tracers). Although subjects were in energy balance during both LOW-CHO and CON, the lower muscle glycogen concentration during LOW-CHO vs. CON (402 ± 29 vs. 540 ± 33 mmol/kg dry wt, P < 0.01) coincided with a significant increase in Si [5.2 ± 0.7 vs. 3.8 ± 0.7 (mU/l)−1·min−1; P < 0.05]. Conversely, despite ingesting several hundred fewer kilocalories after exercise during LOW-EN compared with BAL, this energy deficit did not affect Si the next day [4.9 ± 0.9, and 5.0 ± 0.8 (mU/l)−1·min−1]. Maintaining an energy deficit after exercise had the most potent effect on lipid metabolism, as measured by a higher plasma triacylglycerol concentration, and increased plasma fatty acid mobilization and oxidation compared with when in nutrient balance. Carbohydrate deficit after exercise, but not energy deficit, contributed to the insulin-sensitizing effects of acute aerobic exercise, whereas maintaining an energy deficit after exercise augmented lipid

  16. BDNF-stimulated intracellular signalling mechanisms underlie exercise-induced improvement in spatial memory in the male Wistar rat.

    PubMed

    Bechara, Ranya G; Lyne, Ronan; Kelly, Áine M

    2014-12-15

    Exercise-induced improvements in learning are associated with neurotrophic and neurogenic changes in the dentate gyrus, but the intracellular signalling mechanisms that may mediate these improvements remain unknown. In the current study we investigate the effects of one week of forced exercise on spatial memory and analyse in parallel BDNF-stimulated signalling pathways in cells of the dentate gyrus. Additionally, we test whether a single intracerebroventricular (i.c.v.) injection of BDNF can mimic the observed cognitive and signalling changes. Male Wistar rats were assigned to exercised and sedentary groups and tested in a spatial task post-exercise. Tissue from the dentate gyrus was assessed for expression and release of BDNF, and for changes in expression and activation of TrkB, ERK and synapsin-1. In a separate set of experiments, male Wistar rats received a single i.c.v. injection of BDNF and were then tested in the same spatial learning task. Exercised and BDNF-treated (but not control) rats could successfully complete an object displacement task that tests spatial learning. Exercised rats and BDNF-treated rats displayed increases BDNF expression and ERK1 activation, while exercised rats showed increases in cell division, stimulated BDNF release, TrkB activation, and synapsin-1 expression in the dentate gyrus. We conclude that exercise-induced increases in BDNF in the dentate gyrus are sufficient to cause improvements in spatial memory by activating signalling cascades that enhance synaptic transmission in the hippocampus. PMID:24269499

  17. Exercise-induced alterations in pancreatic oxidative stress and mitochondrial function in type 2 diabetic Goto-Kakizaki rats.

    PubMed

    Raza, Haider; John, Annie; Shafarin, Jasmin; Howarth, Frank C

    2016-04-01

    Progressive metabolic complications accompanied by oxidative stress are the hallmarks of type 2 diabetes. The precise molecular mechanisms of the disease complications, however, remain elusive. Exercise-induced nontherapeutic management of type 2 diabetes is the first line of choice to control hyperglycemia and diabetes associated complications. In this study, using 11-month-old type 2 Goto-Kakizaki (GK) rats, we have investigated the effects of exercise on mitochondrial metabolic and oxidative stress in the pancreas. Our results showed an increase in theNADPHoxidase enzyme activity and reactive oxygen species (ROS) production inGKrats, which was inhibited after exercise. Increased lipid peroxidation and protein carbonylation andSODactivity were also inhibited after exercise. Interestingly, glutathione (GSH) level was markedly high in the pancreas ofGKdiabetic rats even after exercise. However,GSH-peroxidase andGSH-reductase activities were significantly reduced. Exercise also induced energy metabolism as observed by increased hexokinase and glutamate dehydrogenase activities. A significant decrease in the activities of mitochondrial ComplexesII/IIIandIVwere observed in theGKrats. Exercise improved only ComplexIVactivity suggesting increased utilization of oxygen. We also observed increased activities of cytochrome P450s in the pancreas ofGKrats which was reduced significantly after exercise.SDS-PAGEresults have shown a decreased expression ofNF-κB, Glut-2, andPPAR-ϒ inGKrats which was markedly increased after exercise. These results suggest differential oxidative stress and antioxidant defense responses after exercise. Our results also suggest improved mitochondrial function and energy utilization in the pancreas of exercisingGKrats. PMID:27095835

  18. Exercise-induced cramp, myoglobinuria, and tubular aggregates in phosphoglycerate mutase deficiency.

    PubMed

    Oh, Shin J; Park, Kyung-Seok; Ryan, Hewitt F; Danon, Moris J; Lu, Jiesheng; Naini, Ali B; DiMauro, Salvatore

    2006-11-01

    We report two patients in whom phosphoglycerate mutase (PGAM) deficiency was associated with the triad of exercise-induced cramps, recurrent myoglobinuria, and tubular aggregates in the muscle biopsy. Serum creatine kinase (CK) levels were elevated between attacks of myoglobinuria. Forearm ischemic exercise tests produced subnormal increases of venous lactate. Muscle biopsies showed subsarcolemmal tubular aggregates in type 2 fibers. Muscle PGAM activities were markedly decreased (3% of the normal mean) and molecular genetic studies showed that both patients were homozygous for a described missense mutation (W78X). A review of 15 cases with tubular aggregates in the muscle biopsies from our laboratory and 15 cases with PGAM deficiency described in the literature showed that this clinicopathological triad is highly suggestive of PGAM deficiency. PMID:16881065

  19. A Method to Study the Impact of Chemically-induced Ovarian Failure on Exercise Capacity and Cardiac Adaptation in Mice

    PubMed Central

    Chen, Hao; Perez, Jessica N.; Constantopoulos, Eleni; McKee, Laurel; Regan, Jessica; Hoyer, Patricia B.; Brooks, Heddwen L.; Konhilas, John

    2014-01-01

    The risk of cardiovascular disease (CVD) increases in post-menopausal women, yet, the role of exercise, as a preventative measure for CVD risk in post-menopausal women has not been adequately studied. Accordingly, we investigated the impact of voluntary cage-wheel exercise and forced treadmill exercise on cardiac adaptation in menopausal mice. The most commonly used inducible model for mimicking menopause in women is the ovariectomized (OVX) rodent. However, the OVX model has a few dissimilarities from menopause in humans. In this study, we administered 4-vinylcyclohexene diepoxide (VCD) to female mice, which accelerates ovarian failure as an alternative menopause model to study the impact of exercise in menopausal mice. VCD selectively accelerates the loss of primary and primordial follicles resulting in an endocrine state that closely mimics the natural progression from pre- to peri- to post-menopause in humans. To determine the impact of exercise on exercise capacity and cardiac adaptation in VCD-treated female mice, two methods were used. First, we exposed a group of VCD-treated and untreated mice to a voluntary cage wheel. Second, we used forced treadmill exercise to determine exercise capacity in a separate group VCD-treated and untreated mice measured as a tolerance to exercise intensity and endurance. PMID:24747886

  20. A method to study the impact of chemically-induced ovarian failure on exercise capacity and cardiac adaptation in mice.

    PubMed

    Chen, Hao; Perez, Jessica N; Constantopoulos, Eleni; McKee, Laurel; Regan, Jessica; Hoyer, Patricia B; Brooks, Heddwen L; Konhilas, John

    2014-01-01

    The risk of cardiovascular disease (CVD) increases in post-menopausal women, yet, the role of exercise, as a preventative measure for CVD risk in post-menopausal women has not been adequately studied. Accordingly, we investigated the impact of voluntary cage-wheel exercise and forced treadmill exercise on cardiac adaptation in menopausal mice. The most commonly used inducible model for mimicking menopause in women is the ovariectomized (OVX) rodent. However, the OVX model has a few dissimilarities from menopause in humans. In this study, we administered 4-vinylcyclohexene diepoxide (VCD) to female mice, which accelerates ovarian failure as an alternative menopause model to study the impact of exercise in menopausal mice. VCD selectively accelerates the loss of primary and primordial follicles resulting in an endocrine state that closely mimics the natural progression from pre- to peri- to post-menopause in humans. To determine the impact of exercise on exercise capacity and cardiac adaptation in VCD-treated female mice, two methods were used. First, we exposed a group of VCD-treated and untreated mice to a voluntary cage wheel. Second, we used forced treadmill exercise to determine exercise capacity in a separate group VCD-treated and untreated mice measured as a tolerance to exercise intensity and endurance. PMID:24747886

  1. Exercise-induced bronchoconstriction: The effects of montelukast, a leukotriene receptor antagonist

    PubMed Central

    Kemp, James P

    2009-01-01

    Exercise-induced bronchoconstriction (EIB) is very common in both patients with asthma and those who are otherwise thought to be normal. The intensity of exercise as well as the type of exercise is important in producing symptoms. This may make some types of exercise such as swimming more suitable and extended running more difficult for patients with this condition. A better understanding of EIB will allow the physician to direct the patient towards a type of exercise and medications that can result in a more active lifestyle without the same concern for resulting symptoms. This is especially important for schoolchildren who are usually enrolled in physical education classes and elite athletes who may desire to participate in competitive sports. Fortunately several medications (short- and long-acting β2-agonists, cromolyn, nedocromil, inhaled corticosteroids, and more recently leukotriene modifiers) have been shown to be effective in preventing or attenuating the effects of exercise in many patients. In addition, inhaled β2-agonists have been shown to quickly reverse the airway obstruction that develops in patients and continue to be the reliever medications of choice. Inhaled corticosteroids are increasingly being recommended as regular therapy now that the role of inflammation and airway injury has been identified in EIB. With the discovery that there is a release of mediators such as histamine and leukotrienes from cells in the airway following exercise with resulting airway obstruction in susceptible individuals, interest has turned to attenuating their effects with mediator antagonists especially those that block the effects of leukotrienes. Studies with an oral leukotriene antagonist, montelukast, have shown beneficial effects in adults and children aged as young as 6 years with EIB. These effects can be demonstrated as soon as two hours and as long as 24 hours after administration without a demonstrated loss of a protective effect after months of treatment

  2. Hormonal responses to exercise after partial sleep deprivation and after a hypnotic drug-induced sleep.

    PubMed

    Mougin, F; Bourdin, H; Simon-Rigaud, M L; Nguyen, N U; Kantelip, J P; Davenne, D

    2001-02-01

    The aim of this study was to determine the hormonal responses, which are dependent on the sleep wake cycle, to strenuous physical exercise. Exercise was performed after different nocturnal regimens: (i) a baseline night preceded by a habituation night; (ii) two nights of partial sleep deprivation caused by a delayed bedtime or by an early awakening; and (iii) two nights of sleep after administration of either a hypnotic compound (10 mg zolpidem) or a placebo. Eight well-trained male endurance athletes with a maximal oxygen uptake of 63.5 +/- 3.8 ml x kg(-1) x min(-1) (mean value +/- s(x)) were selected on the basis of their sleeping habits and their physical training. Polygraphic recordings of EEG showed that both nights with partial sleep loss led to a decrease (P< 0.01) in stage 2 and rapid eye movement sleep. A delayed bedtime also led to a decrease (P < 0.05) in stage 1 sleep. Zolpidem had no effect on the different stages of sleep. During the afternoon after an experimental night, exercise was performed on a cycle ergometer. After a 10-min warm-up, the participants performed 30 min steady-state cycling at 75% VO(2-max) followed by a progressively increased workload until exhaustion. The recovery period lasted 30 min. Plasma growth hormone, prolactin, cortisol, catecholamine and lactate concentrations were measured at rest, during exercise and after recovery. The concentration of plasma growth hormone and catecholamine were not affected by partial sleep deprivation, whereas that of plasma prolactin was higher (P < 0.05) during the trial after an early awakening. Plasma cortisol was lower (P < 0.05) during recovery after both sleep deprivation conditions. Blood lactate was higher (P < 0.05) during submaximal exercise performed after both a delayed bedtime and an early awakening. Zolpidem-induced sleep did not affect the hormonal and metabolic responses to subsequent exercise. Our results demonstrate only minor alterations in the hormonal responses to exercise

  3. Effect of New Zealand blueberry consumption on recovery from eccentric exercise-induced muscle damage

    PubMed Central

    2012-01-01

    Background Exercise-induced muscle damage (EIMD) is accompanied by localized oxidative stress / inflammation which, in the short-term at least, is associated with impaired muscular performance. Dietary antioxidants have been shown to reduce excessive oxidative stress; however, their effectiveness in facilitating recovery following EIMD is not clear. Blueberries demonstrate antioxidant and anti-inflammatory properties. In this study we examine the effect of New Zealand blueberries on EIMD after strenuous eccentric exercise. Methods In a randomized cross-over design, 10 females consumed a blueberry smoothie or placebo of a similar antioxidant capacity 5 and 10 hours prior to and then immediately, 12 and 36 hours after EIMD induced by 300 strenuous eccentric contractions of the quadriceps. Absolute peak and average peak torque across the knee, during concentric, isometric, and eccentric actions were measured. Blood biomarkers of oxidative stress, antioxidant capacity, and inflammation were assessed at 12, 36 and 60 hours post exercise. Data were analyzed using a two-way ANOVA. Results A significant (p < 0.001) decrease in isometric, concentric and eccentric torque was observed 12 hours following exercise in both treatment groups. During the 60 hour recovery period, a significant (p = 0.047) interaction effect was seen for peak isometric tension suggesting a faster rate of recovery in the blueberry intervention group. A similar trend was observed for concentric and eccentric strength. An increase in oxidative stress and inflammatory biomarkers was also observed in both treatment groups following EIMD. Although a faster rate of decrease in oxidative stress was observed in the blueberry group, it was not significant (p < 0.05) until 36 hours post-exercise and interestingly coincided with a gradual increase in plasma antioxidant capacity, whereas biomarkers for inflammation were still elevated after 60 hours recovery. Conclusions This study demonstrates that

  4. Acute Resistance Exercise Induces Antinociception by Activation of the Endocannabinoid System in Rats

    PubMed Central

    Galdino, Giovane; Romero, Thiago; da Silva, José Felippe Pinho; Aguiar, Daniele; de Paula, Ana Maria; Cruz, Jader; Parrella, Cosimo; Piscitelli, Fabiana; Duarte, Igor; Di Marzo, Vincenzo; Perez, Andrea

    2014-01-01

    Background Resistance exercise (RE) is also known as strength training, and it is performed to increase the strength and mass of muscles, bone strength and metabolism. RE has been increasingly prescribed for pain relief. However, the endogenous mechanisms underlying this antinociceptive effect are still largely unexplored. Thus, we investigated the involvement of the endocannabinoid system in RE-induced antinociception. Methods Male Wistar rats were submitted to acute RE in a weight-lifting model. The nociceptive threshold was measured by a mechanical nociceptive test (paw pressure) before and after exercise. To investigate the involvement of cannabinoid receptors and endocannabinoids in RE-induced antinociception, cannabinoid receptor inverse agonists, endocannabinoid metabolizing enzyme inhibitors and an anandamide reuptake inhibitor were injected before RE. After RE, CB1 cannabinoid receptors were quantified in rat brain tissue by Western blot and immunofluorescence. In addition, endocannabinoid plasma levels were measured by isotope dilution-liquid chromatography mass spectrometry. Results RE-induced antinociception was prevented by preinjection with CB1 and CB2 cannabinoid receptor inverse agonists. By contrast, preadministration of metabolizing enzyme inhibitors and the anandamide reuptake inhibitor prolonged and enhanced this effect. RE also produced an increase in the expression and activation of CB1 cannabinoid receptors in rat brain tissue and in the dorsolateral and ventrolateral periaqueductal regions and an increase of endocannabinoid plasma levels. Conclusion The present study suggests that a single session of RE activates the endocannabinoid system to induce antinociception. PMID:24977916

  5. Both aerobic exercise and resveratrol supplementation attenuate doxorubicin-induced cardiac injury in mice.

    PubMed

    Dolinsky, Vernon W; Rogan, Kyle J; Sung, Miranda M; Zordoky, Beshay N; Haykowsky, Mark J; Young, Martin E; Jones, Lee W; Dyck, Jason R B

    2013-07-15

    Because doxorubicin (DOX)-containing chemotherapy causes left ventricular (LV) dysfunction and remodeling that can progress to heart failure, strategies to alleviate DOX cardiotoxicity are necessary to improve health outcomes of patients surviving cancer. Although clinical evidence suggests that aerobic exercise training (ET) can prevent cardiotoxicity in patients undergoing DOX chemotherapy, the physiological mechanisms involved have not been extensively studied, nor is it known whether compounds [such as resveratrol (RESV)] have similar beneficial effects. With the use of a murine model of chronic DOX exposure, this study compared the efficacy of modest ET to RESV treatment on exercise performance, LV remodeling, and oxidative stress resistance. Mice were divided into four groups that received saline, DOX (8 mg/kg ip, one time per week), DOX + RESV (4 g/kg diet, ad libitum), and DOX + ET (45 min of treadmill exercise, 5 days/wk) for 8 wk. LV function and morphology were evaluated by in vivo echocardiography. DOX caused adverse LV remodeling that was partially attenuated by modest ET and completely prevented by RESV. These effects were paralleled by improvements in exercise performance. The cardioprotective properties of ET and RESV were associated with reduced levels of atrial natriuretic peptide and the lipid peroxidation by-product, 4-hydroxy-2-nonenal. In addition, ET and RESV increased the expression of cardiac sarcoplasmic/endoplasmic reticulum calcium-ATPase 2a, superoxide dismutase, mitochondrial electron transport chain complexes, and mitofusin-1 and -2 in mice administered DOX. Compared with modest ET, RESV more effectively prevented DOX-induced LV remodeling and was associated with the reduction of DOX-induced oxidative stress. Our findings have important implications for protecting patients against DOX-associated cardiac injury. PMID:23695218

  6. Do changes in energy intake and non-exercise physical activity affect exercise-induced weight loss? Midwest Exercise Trial-2

    PubMed Central

    Herrmann, Stephen D.; Willis, Erik A.; Honas, Jeffery J.; Lee, Jaehoon; Washburn, Richard A.; Donnelly, Joseph E.

    2015-01-01

    Objective To compare energy intake, total daily energy expenditure (TDEE), non-exercise energy expenditure (NEEx), resting metabolic rate (RMR), non-exercise physical activity (NEPA), and sedentary time between participants with weight loss <5% (non-responders) vs. ≥5% (responders) in response to exercise. Methods Overweight/obese (BMI 25–40 kg/m2), adults (18–30 yrs.) were randomized to exercise: 5 day/week, 400 or 600 kcal/session, 10 months. Results Forty participants responded and 34 did not respond to the exercise protocol. Non-responder energy intake was higher vs. responders, significant only in men (p=0.034). TDEE increased only in responders (p=0.001). NEEx increased in responders and decreased in non-responders, significant only in men (p=0.045). There were no within or between-group differences for change in RMR. NEPA increased in responders and decreased in non-responders (group-by-time interactions: total sample, p=0.049; men, p=0.016). Sedentary time decreased in both groups, significant only in men. Conclusion Men who did not lose weight in response to exercise (<5%) had higher energy intake and lower NEEx compared to men losing ≥5%. No significant differences in any parameters assessed were observed between women who lost <5% vs. those losing ≥5. Factors associated with the weight loss response to exercise in women warrant additional investigation. PMID:26193059

  7. Regular exercise alleviates renovascular hypertension-induced cardiac/endothelial dysfunction and oxidative injury in rats.

    PubMed

    Kumral, Z N O; Sener, G; Ozgur, S; Koc, M; Suleymanoglu, S; Hurdag, C; Yegen, B C

    2016-02-01

    The importance of physical activity in the management of renovascular diseases is well-known, but lacks evidence of underlying mechanisms. The purpose of the study was to elucidate the protective/therapeutic effects of regular exercise on experimental renovascular hypertension (RVH)-induced oxidative stress and cardiac dysfunction. Wistar albino rats underwent a RVH surgery (2K1C, Goldblatt). Three weeks later half of the rats started swimming exercise for 9 weeks (n = 15), while the sedentary RVH group (n = 15) had no exercise during that period. Sham-operated control rats (n = 10), had the similar surgical procedures but the left renal artery was left unclipped. Body weights were monitored, and blood pressures were measured weekly using tail-cuff. Echocardiographic evaluation was performed on the 3(rd) week and on the 12(th) week of the experiment before the rats were decapitated. Heart and thoracic aorta were removed and serum was collected, while aortic samples were put in a 10% formaldehyde solution for immunochemistry. Cardiac tissue samples obtained from each animal were used for the determination of tissue myeloperoxidase (MPO) and catalase (CAT) activities, malondialdehyde (MDA), and glutathione (GSH) levels. In the sedentary RVH group, aortic contractile response (contraction/relaxation in isolated organ bath), left ventricular diastolic and systolic dimensions, and immunohistochemical staining of aortic inducible nitric oxide synthase (iNOS) were increased, while ejection fraction and aortic endothelial nitric oxide synthase (eNOS) staining were decreased. RVH in the sedentary rats resulted in increased pro-inflammatory cytokines (TNF-α, IL-2, IL-6), lipid peroxidation (malondialdehyde) and neutrophil infiltration (myeloperoxidase activity) along with reductions in antioxidant glutathione and catalase levels in the cardiac tissue. Exercise after RVH increased the immunhistochemical staining of aortic eNOS, decreased iNOS staining and reversed the

  8. Exercise training starting at weaning age preserves cardiac pacemaker function in adulthood of diet-induced obese rats.

    PubMed

    Carvalho de Lima, Daniel; Guimarães, Juliana Bohnen; Rodovalho, Gisele Vieira; Silveira, Simonton Andrade; Haibara, Andrea Siqueira; Coimbra, Cândido Celso

    2014-08-01

    Peripheral sympathetic overdrive in young obese subjects contributes to further aggravation of insulin resistance, diabetes, and hypertension, thus inducing worsening clinical conditions in adulthood. Exercise training has been considered a strategy to repair obesity autonomic dysfunction, thereby reducing the cardiometabolic risk. Therefore, the aim of this study was to assess the effect of early exercise training, starting immediately after weaning, on cardiac autonomic control in diet-induced obese rats. Male Wistar rats (weaning) were divided into four groups: (i) a control group (n = 6); (ii) an exercise-trained control group (n = 6); (iii) a diet-induced obesity group (n = 6); and (iv) an exercise-trained diet-induced obesity group (n = 6). The development of obesity was induced by 9 weeks of palatable diet intake, and the training program was implemented in a motor-driven treadmill (5 times per week) during the same period. After this period, animals were submitted to vein and artery catheter implantation to assess cardiac autonomic balance by methylatropine (3 mg/kg) and propranolol (4 mg/kg) administration. Exercise training increased running performance in both groups (p < 0.05). Exercise training also prevented the increased resting heart rate in obese rats, which seemed to be related to cardiac pacemaker activity preservation (p < 0.05). Additionally, the training program preserved the pressure and bradycardia responses to autonomic blockade in obese rats (p < 0.05). An exercise program beginning at weaning age prevents cardiovascular dysfunction in obese rats, indicating that exercise training may be used as a nonpharmacological therapeutic strategy for the treatment of cardiometabolic diseases. PMID:24806307

  9. Distinct neuroplasticity processes are induced by different periods of acrobatic exercise training.

    PubMed

    Salame, Samira; Garcia, Priscila C; Real, Caroline C; Borborema, Juliana; Mota-Ortiz, Sandra R; Britto, Luiz R G; Pires, Raquel S

    2016-07-15

    Short and long-term physical exercise induce physiological and structural changes in brain motor areas. The relationship between changes of structural and synaptic proteins in brain motor areas and acrobatic exercise is less understood. Our aim was to evaluate the expression of synapsin I (SYS), synaptophysin (SYP), microtubule-associated protein 2 (MAP2), neurofilament (NF), and a marker for recent neuronal activity (Egr-1) in the motor cortex, striatum and cerebellum of adult rats subjected to acrobatic exercise (AE, for 1-4 weeks). We used adult Wistar rats, divided into 4 groups based on duration of acrobatic training, namely 1 week (AE1, n=15), 2 weeks (AE2, n=15), 4 weeks (AE4, n=15), and sedentary (SED, n=15). In AE groups, the rats covered 5 times a circuit that was composed of obstacles, three times a week. The protein levels were analyzed by immunoblotting and immunohistochemistry. The results revealed that short-term AE (AE1 and AE2) induced MAP2 decreases and NF, SYP and Egr-1 increases in the motor cortex; an increase of MAP2, SYS and SYP in the dorsolateral striatum, whereas the dorsomedial striatum showed increased NF, SYS, SYP and Egr-1. Granular cerebellar layer showed increased NF and Egr-1, with increased NF and SYP in the molecular layer. Long-term AE (AE4) promoted an increase of MAP2, SYP and Egr-1 in motor cortex; MAP2, SYS and SYP in the dorsomedial striatum; and NF and Egr-1 in the cerebellar granular layer. In conclusion, our data suggest that different durations of AE induce distinct plastic responses among distinct cortical and subcortical circuits. PMID:27126278

  10. Loss of functional endothelial connexin40 results in exercise-induced hypertension in mice.

    PubMed

    Morton, Susan K; Chaston, Daniel J; Howitt, Lauren; Heisler, Jillian; Nicholson, Bruce J; Fairweather, Stephen; Bröer, Stefan; Ashton, Anthony W; Matthaei, Klaus I; Hill, Caryl E

    2015-03-01

    During activity, coordinated vasodilation of microcirculatory networks with upstream supply vessels increases blood flow to skeletal and cardiac muscles and reduces peripheral resistance. Endothelial dysfunction in humans attenuates activity-dependent vasodilation, resulting in exercise-induced hypertension in otherwise normotensive individuals. Underpinning activity-dependent hyperemia is an ascending vasodilation in which the endothelial gap junction protein, connexin (Cx)40, plays an essential role. Because exercise-induced hypertension is proposed as a forerunner to clinical hypertension, we hypothesized that endothelial disruption of Cx40 function in mice may create an animal model of this condition. To this end, we created mice in which a mutant Cx40T152A was expressed alongside wildtype Cx40 selectively in the endothelium. Expression of the Cx40T152A transgene in Xenopus oocytes and mouse coronary endothelial cells in vitro impaired both electric and chemical conductance and acted as a dominant-negative against wildtype Cx40, Cx43, and Cx45, but not Cx37. Endothelial expression of Cx40T152A in Cx40T152ATg mice attenuated ascending vasodilation, without effect on radial coupling through myoendothelial gap junctions. Using radiotelemetry, Cx40T152ATg mice showed an activity-dependent increase in blood pressure, which was significantly greater than in wildtype mice, but significantly less than in chronically hypertensive, Cx40knockout mice. The increase in heart rate with activity was also greater than in wildtype or Cx40knockout mice. We conclude that the endothelial Cx40T152A mutation attenuates activity-dependent vasodilation, producing a model of exercise-induced hypertension. These data highlight the importance of endothelial coupling through Cx40 in regulating blood pressure during activity. PMID:25547341

  11. Wheat-dependent exercise-induced anaphylaxis sensitized with hydrolyzed wheat protein in soap.

    PubMed

    Chinuki, Yuko; Morita, Eishin

    2012-12-01

    Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a specific form of wheat allergy typically induced by exercise after ingestion of wheat products. Wheat ω-5 gliadin is a major allergen associated with conventional WDEIA, and detection of serum immunoglobulin E (IgE) specific to recombinant ω-5 gliadin is a reliable method for its diagnosis. Recently, an increased incidence of a new subtype of WDEIA, which is likely to be sensitized via a percutaneous and/or rhinoconjunctival route to hydrolyzed wheat protein (HWP), has been observed. All of the patients with this new subtype had used the same brand of soap, which contained HWP. Approximately half of these patients developed contact allergy several months later and subsequently developed WDEIA. In each of these patients, contact allergy with soap exposure preceded food ingestion-induced reactions. Other patients directly developed generalized symptoms upon ingestion of wheat products. The predominant observed symptom of the new WDEIA subtype was angioedema of the eyelids; a number of patients developed anaphylaxis. This new subtype of WDEIA has little serum ω-5 gliadin-specific serum IgE. PMID:23093796

  12. Exercise induced sympathetic influences do not change interatrial conduction times in VDD and DDD pacing.

    PubMed

    Ismer, B; Von Knorre, G H; Voss, W; Grille, W; Klenke, G; Pulya, K; Koglek, W; Suntinger, A; Luessow, H

    1996-11-01

    Using telemetry, right atrial electrogram (RA), and marker channel of atrial sense events (MA) in combination with the left atrial electrogram (LA), recorded by a filtered bipolar esophageal lead, interatrial conduction during submaximal exercise and at rest was examined in 46 DDD pacemaker patients. The RA-LA and MA-LA conduction times measured in the presence of atrial sensing (VDD) as well as the conduction time SA-LA from atrial stimulus (SA) to LA, determined during atrial pacing (DDD) were found to be individual constants independent of exercise induced sympathetic influences. Thus, having determined an optimal mechanical interval (LA-LV)mech/opt from left atrium to ventricle by other methods, the optimal AV delay for DDD as well as for VDD operation can be calculated by the sum of the appropriate interatrial conduction time (SA-LA, respectively MA-LA) and the (LA-LV)mech/opt interval. Due to the constant SA-LA and MA-LA, the difference between these two values (AV delay correction interval) is a constant as well, which remains unchanged during exercise. Therefore, in selecting the rate responsive AV delay, only hemodynamic and not electrophysiological measurements need to be considered. PMID:8945041

  13. Could a vegetarian diet reduce exercise-induced oxidative stress? A review of the literature.

    PubMed

    Trapp, Denise; Knez, Wade; Sinclair, Wade

    2010-10-01

    Oxidative stress is a natural physiological process that describes an imbalance between free radical production and the ability of the antioxidant defence system of the body to neutralize free radicals. Free radicals can be beneficial as they may promote wound healing and contribute to a healthy immune response. However, free radicals can have a detrimental impact when they interfere with the regulation of apoptosis and thus play a role in the promotion of some cancers and conditions such as cardiovascular disease. Antioxidants are molecules that reduce the damage associated with oxidative stress by counteracting free radicals. Regular exercise is a vital component of a healthy lifestyle, although it can increase oxidative stress. As a typical vegetarian diet comprises a wide range of antioxidant-rich foods, it is plausible that the consumption of these foods will result in an enhanced antioxidant system capable of reducing exercise-induced oxidative stress. In addition, a relationship between a vegetarian diet and lower risks of cardiovascular disease and some cancers has been established. This review explores the current available evidence linking exercise, vegetarians, antioxidants, and oxidative stress. PMID:20845212

  14. The Intervention Effects of Acupuncture on Fatigue Induced by Exhaustive Physical Exercises: A Metabolomics Investigation

    PubMed Central

    Ma, Haifeng; Liu, Xia; Wu, Ying; Zhang, Naixia

    2015-01-01

    In this study, the antifatigue effects of acupuncture had been investigated at the metabolic level on the young male athletes with exhaustive physical exercises. After a series of exhaustive physical exercises and a short-term rest, the athletes either were treated with needling acupuncture on selected acupoints (TA group) or enjoyed an extended rest (TR group). NMR-based metabolomics analysis was then applied to depict the metabolic profiles of urine samples, which were collected from the athletes at three time points including the time before exercises, the time before and after the treatment of acupuncture, or taking the extended rest. The results from multivariate statistical analysis indicated that the recoveries of disturbed metabolites in the athletes treated with acupuncture were significantly faster than in those only taking rest. After the treatment with acupuncture, the levels of distinguished metabolites, 2-hydroxybutyrate, 3-hydroxyisovalerate, lactate, pyruvate, citrate, dimethylglycine, choline, glycine, hippurate, and hypoxanthine were recovered at an accelerated speed in the TA group in comparison with the TR group. The above-mentioned results indicated that the acupuncture treatment ameliorated fatigue by backregulating the perturbed energy metabolism, choline metabolism, and attenuating the ROS-induced stress at an accelerated speed, which demonstrated that acupuncture could serve as an alternative fatigue-relieving approach. PMID:26442121

  15. Effects of vitamin E supplementation on exercise-induced oxidative stress: a meta-analysis.

    PubMed

    Stepanyan, Vahan; Crowe, Melissa; Haleagrahara, Nagaraja; Bowden, Bruce

    2014-09-01

    Tocopherols (commonly referred to as "vitamin E") are frequently studied antioxidants in exercise research. However, the studies are highly heterogeneous, which has resulted in contradicting opinions. The aim of this review is to identify similar studies investigating the effects of tocopherol supplementation on exercise performance and oxidative stress and to perform minimally biased qualitative comparisons and meta-analysis. The literature search and study selection were performed according to Cochrane guidelines. A 2-dimensional study execution process was developed to enable selection of similar and comparable studies. Twenty relevant studies were identified. The high variability of study designs resulted in final selection of 6 maximally relevant studies. Markers of lipid peroxidation (malondialdehyde) and muscle damage (creatine kinase) were the 2 most frequently and similarly measured variables. Meta comparison showed that tocopherol supplementation did not result in significant protection against either exercise-induced lipid peroxidation or muscle damage. The complex antioxidant nature of tocopherols and low accumulation rates in muscle tissues could underlie an absence of protective effects. PMID:25068790

  16. Exercise-induced bronchospasm: A case study in a nonasthmatic patient

    PubMed Central

    Hayden, Mary Lou; Stoloff, Stuart W; Colice, Gene L; Ostrom, Nancy K; Eid, Nemr S; Parsons, Jonathan P

    2012-01-01

    Purpose To provide an overview of the clinical presentation, diagnosis, and management of exercise-induced bronchospasm (EIB) without underlying asthma. Data sources Case presentation and review of the EIB Landmark Survey. Conclusions EIB is a common and well-described occurrence in patients with asthma, as well as in patients with no overt respiratory condition. Treatment with a short-acting beta-agonist before starting exercise is effective, yet this treatment approach is underutilized in the majority of patients with asthma. Implications for practice This case highlights the implications of undermanaged EIB and the disconnect between healthcare provider recommendations and the beliefs and behaviors in patients with EIB. Inhaled short-acting beta-agonists can attenuate EIB in 80%–95% of patients and are effective during 2–3 h of exercise. Patients with a compromised level of physical activity because of EIB who do not respond to conventional treatment strategies should be referred to a respiratory specialist for diagnostic evaluation and confirmation of underlying asthma. Nurse practitioners should remain vigilant to identify untreated EIB and ensure that affected patients understand the condition and appropriate treatment options. PMID:22243677

  17. Plasma levels of trace elements and exercise induced stress hormones in well-trained athletes.

    PubMed

    Soria, Marisol; González-Haro, Carlos; Ansón, Miguel; López-Colón, José L; Escanero, Jesús F

    2015-01-01

    This study analyzed the variation and relationship of several trace elements, metabolic substrates and stress hormones activated by exercise during incremental exercise. Seventeen well-trained endurance athletes performed a cycle ergometer test: after a warm-up of 10 min at 2.0 W kg(-1), the workload was increased by 0.5 W kg(-1) every 10 min until exhaustion. Prior diet, activity patterns, and levels of exercise training were controlled, and tests timed to minimize variations due to the circadian rhythm. Oxygen uptake, blood lactate concentration, plasma ions (Zn, Se, Mn and Co), serum glucose, non-esterified fatty acids (NEFAs) and several hormones were measured at rest, at the end of each stage and 3, 5 and 7 min post-exercise. Urine specific gravity was measured before and after the test, and participants drank water ad libitum. Significant differences were found in plasma Zn and Se levels as a function of exercise intensity. Zn was significantly correlated with epinephrine, norepinephrine and cortisol (r = 0.884, P < 0.01; r = 0.871, P < 0.01; and r = 0.808, P = 0.05); and Se showed significant positive correlations whit epinephrine and cortisol (r = 0.743, P < 0.05; and r = 0.776, P < 0.05). Neither Zn nor Se levels were associated with insulin or glucagon, and neither Mn nor Co levels were associated with any of the hormones or substrate metabolites studied. Further, while Zn levels were found to be associated only with lactate, plasma Se was significantly correlated with lactate and glucose (respectively for Zn: r = 0.891, P < 0.01; and for Se: r = 0.743, P < 0.05; r = 0.831, P < 0.05). In conclusion, our data suggest that there is a positive correlation between the increases in plasma Zn or Se and stress hormones variations induced by exercise along different submaximal intensities in well-hydrated well-trained endurance athletes. PMID:26004901

  18. Exercise-induced acute compartment syndrome in a young man, occurring after a short race.

    PubMed

    Basnet, Bibhusan; Matar, Mousa; Vaitilingham, Siddharthan; Chalise, Shyam; Irooegbu, Nkem; Bang, Jane

    2016-04-01

    We describe a case of exercise-induced acute compartment syndrome (ACS) in a 23-year-old man who presented to his primary care physician 48 hours after he attempted to run a 5K race. He noticed searing pain in his left leg after the first half mile but had no other symptoms. He was referred to the emergency department and diagnosed with ACS, and a fasciotomy was done. A presentation of limb pain that is out of proportion to a known or suspected injury should prompt consideration of ACS. Early recognition and surgical management are essential to achieving the best possible outcome. PMID:27034546

  19. Where to from here for exercise-induced bronchoconstriction: the unanswered questions.

    PubMed

    Hallstrand, Teal S; Kippelen, Pascale; Larsson, Johan; Bougault, Valérie; van Leeuwen, Janneke C; Driessen, Jean M M; Brannan, John D

    2013-08-01

    The role of epithelial injury is an unanswered question in those with established asthma and in elite athletes who develop features of asthma and exercise-induced bronchorestriction (EIB) after years of training. The movement of water in response to changes in osmolarity is likely to be an important signal to the epithelium that may be central to the onset of EIB. It is generally accepted that the mast cell and its mediators play a major role in EIB and the presence of eosinophils is likely to enhance EIB severity. PMID:23830134

  20. Exercise-induced acute compartment syndrome in a young man, occurring after a short race

    PubMed Central

    Matar, Mousa; Vaitilingham, Siddharthan; Chalise, Shyam; Irooegbu, Nkem; Bang, Jane

    2016-01-01

    We describe a case of exercise-induced acute compartment syndrome (ACS) in a 23-year-old man who presented to his primary care physician 48 hours after he attempted to run a 5K race. He noticed searing pain in his left leg after the first half mile but had no other symptoms. He was referred to the emergency department and diagnosed with ACS, and a fasciotomy was done. A presentation of limb pain that is out of proportion to a known or suspected injury should prompt consideration of ACS. Early recognition and surgical management are essential to achieving the best possible outcome. PMID:27034546

  1. Acute Exercise-Induced Compartment Syndrome of the Leg- Don’t Miss It

    PubMed Central

    Khare, Manish Kumar; Mishra, Sumanta; Marhual, Jogesh Chandra

    2016-01-01

    Acute exercise induced compartment syndrome of leg is a very rare and very oftenly missed entity which leads to delay in its management. We are presenting such case in which diagnosis was established two days after the onset of symptoms. Urgent decompressive fasciotomy was done. After 3 months of follow up, patient has got full functional recovery of his affected limb. This case highlights the importance of keeping high index of clinical suspicion to diagnose the problem and manage promptly. We have reviewed the English literature and found only about 40 cases since 1945. PMID:27042521

  2. Biphasic Peptide Amphiphile Nanomatrix Embedded with Hydroxyapatite Nanoparticles for Stimulated Osteoinductive Response

    PubMed Central

    Anderson, Joel M.; Patterson, Jessica L.; Vines, Jeremy B.; Javed, Amjad; Gilbert, Shawn R.; Jun, Ho-Wook

    2013-01-01

    Formation of the native bone extracellular matrix (ECM) provides an attractive template for bone tissue engineering. The structural support and biological complexity of bone ECM are provided within a composite microenvironment that consists of an organic fibrous network reinforced by inorganic hydroxyapatite (HA) nanoparticles. Recreating this biphasic assembly, a bone ECM analogous scaffold comprised of self-assembling peptide amphiphile (PA) nanofibers and interspersed HA nanoparticles was investigated. PAs were endowed with biomolecular ligand signaling using a synthetically inscribed peptide sequence (i.e. RGDS) and integrated with HA nanoparticles to form a biphasic nanomatrix hydrogel. It was hypothesized the biphasic hydrogel would induce osteogenic differentiation of human mesenchymal stem cells (hMSCs) and improve bone healing as mediated by RGDS ligand signaling within PA nanofibers and embedded HA mineralization source. Viscoelastic stability of the biphasic PA hydrogels was evaluated with different weight concentrations of HA for improved gelation. After demonstrating initial viability, long-term cellularity and osteoinduction of encapsulated hMSCs in different PA hydrogels were studied in vitro. Temporal progression of osteogenic maturation was assessed by gene expression of key markers. A preliminary animal study demonstrated bone healing capacity of the biphasic PA nanomatrix under physiological conditions using a critical size femoral defect rat model. The combination of RGDS ligand signaling and HA nanoparticles within the biphasic PA nanomatrix hydrogel demonstrated the most effective osteoinduction and comparative bone healing response. Therefore, the biphasic PA nanomatrix establishes a well-organized scaffold with increased similarity to natural bone ECM with the prospect for improved bone tissue regeneration. PMID:22077993

  3. Exercise-induced changes in atrial peptides in relation to neuroendocrine responses and fluid balance in the horse.

    PubMed

    Kokkonen, U M; Pösö, A R; Hyyppä, S; Huttunen, P; Leppäluoto, J

    2002-04-01

    Previous data show that, in horses, plasma atrial natriuretic peptides (ANP and NT-ANP) remain elevated for a long time after exercise. To study whether exercise-induced changes in hormonal and fluid balance explain this, we measured plasma concentrations of COOH- and NH2-terminal atrial natriuretic peptides (ANP(99-129) and NT-ANP(1-98) together with arginine vasopressin (AVP), adrenocorticotrophin (ACTH), beta-endorphin, cortisol, catecholamines, and indicators of fluid balance in six Finnhorses after a graded submaximal exercise test on a treadmill. After exercise, AVP and catecholamines diminished rapidly; atrial peptides, ACTH, beta-endorphin, and cortisol remained elevated longer. ANP reached its peak value at 5 min and NT-ANP at 30 min post-exercise. At 60 min, ANP was still significantly increased and NT-ANP even above its level at the end of exercise. The different temporal patterns of ANP and NT-ANP are most probably explained by differences in their plasma half-lives. The post-exercise increase in NT-ANP indicates that the release of atrial peptides is stimulated during recovery after exercise. The rapid decrease in AVP and catecholamines suggests that these hormones do not explain the long-lasting increase in atrial peptides. Cortisol remained elevated longer and it may have contributed to some extent. After exercise, the packed cell volume (PCV) decreased more slowly than plasma total protein and electrolytes, which refers to a slow post-exercise return in blood volume. Taken together, the present results show that the long-lasting post-exercise increase in plasma atrial peptides in horses is most probably explained by elevated central blood volume and that the role of vasoactive hormones is small. PMID:12019955

  4. Section 2. Exercise-Induced Bronchospasm: Albuterol versus Montelukast: Highlights of the Asthma Summit 2009: Beyond the Guidelines

    PubMed Central

    2010-01-01

    Exercise-induced bronchospasm (EIB) involves airway obstruction with an onset shortly after exercising. It can occur in individuals without a diagnosis of asthma, but is most common in asthmatic patients (and in this scenario may be referred to as exercise-induced asthma, EIA), correlating with the patient's degree of airway hyperreactivity. While albuterol is the most commonly used rescue and prophylactic medication for EIB, the leukotriene antagonist, monetlukast, may be an appropriate choice for some patients. Clinical data have shown that once-daily treatment with montelukast (5 or 10 mg tablet) can offer protection against EIB within 3 days for some patients. Such an approach might be preferred for patients who have difficulty with inhaled medications and for children who cannot access their inhalers during the school day. Montelukast also may be an option to reduce side effects associated with albuterol for individuals who exercise regularly. PMID:24228852

  5. Biphasic Investigation of Tissue Mechanical Response During Freezing Front Propagation

    PubMed Central

    Wright, Jamie; Han, Bumsoo; Chuong, Cheng-Jen

    2012-01-01

    Cryopreservation of engineered tissue (ET) has achieved limited success due to limited understanding of freezing-induced biophysical phenomena in ETs, especially fluid-matrix interaction within ETs. To further our understanding of the freezing-induced fluid-matrix interaction, we have developed a biphasic model formulation that simulates the transient heat transfer and volumetric expansion during freezing, its resulting fluid movement in the ET, elastic deformation of the solid matrix and the corresponding pressure redistribution within. Treated as a biphasic material, the ET consists of a porous solid matrix fully saturated with interstitial fluid. Temperature-dependent material properties were employed and phase change was included by incorporating the latent heat of phase change into an effective specific heat term. Model-predicted temperature distribution, the location of the moving freezing front, and the ET deformation rates through the time course compare reasonably well with experiments reported previously. Results from our theoretical model show that behind the marching freezing front, the ET undergoes expansion due to phase change of its fluid contents. It compresses the region preceding the freezing front leading to its fluid expulsion and reduced regional fluid volume fractions. The expelled fluid is forced forward and upward into the region further ahead of the compression zone causing a secondary expansion zone; which then compresses the region further downstream with much reduced intensity. Overall, it forms an alternating expansion-compression pattern which moves with the marching freezing front. The present biphasic model helps us to gain insights into some facets of the freezing process and cryopreservation treatment that could not be gleaned experimentally. Its resulting understanding will ultimately be useful to design and improve cryopreservation protocols for ETs. PMID:22757502

  6. Effects of exercise-induced arterial hypoxaemia and work rate on diaphragmatic fatigue in highly trained endurance athletes

    PubMed Central

    Vogiatzis, Ioannis; Georgiadou, Olga; Giannopoulou, Ifigenia; Koskolou, Maria; Zakynthinos, Spyros; Kostikas, Konstantinos; Kosmas, Epaminondas; Wagner, Harrieth; Peraki, Eleni; Koutsoukou, Antonia; Koulouris, Nickolaos; Wagner, Peter D; Roussos, Charis

    2006-01-01

    Diaphragmatic fatigue occurs in highly trained athletes during exhaustive exercise. Since approximately half of them also exhibit exercise-induced arterial hypoxaemia (EIAH) during high-intensity exercise, the present study sought to test the hypothesis that arterial hypoxaemia contributes to exercise-induced diaphragmatic fatigue in this population. Ten cyclists (: 70.0 ± 1.6 ml kg−1 min−1; mean ± s.e.m.) completed, in a balanced ordering sequence, one normoxic (end-exercise arterial O2 saturation (Sa,O2): 92 ± 1%) and one hyperoxic (FI,O2: 0.5% O2; Sa,O2: 97 ± 1%) 5 min exercise test at intensities equal to 80 ± 3 and 90 ± 3% of maximal work rate (WRmax), respectively, producing the same tidal volume (VT) and breathing frequency (f) throughout exercise. Cervical magnetic stimulation was used to determine reduction in twitch transdiaphragmatic pressure (Pdi,tw) during recovery. Hyperoxic exercise at 90% WRmax induced significantly (P = 0.022) greater post-exercise reduction in Pdi,tw (15 ± 2%) than did normoxic exercise at 80% WRmax (9 ± 2%), despite the similar mean ventilation (123 ± 8 and 119 ± 8 l min−1, respectively), breathing pattern (VT: 2.53 ± 0.05 and 2.61 ± 0.05 l, f: 49 ± 2 and 46 ± 2 breaths min−1, respectively), mean changes in Pdi during exercise (37.1 ± 2.4 and 38.2 ± 2.8 cmH2O, respectively) and end-exercise arterial lactate (12.1 ± 1.4 and 10.8 ± 1.1 mmol l−1, respectively). The difference found in diaphragmatic fatigue between the hyperoxic (at higher leg work rate) and the normoxic (at lower leg work rate) tests suggests that neither EIAH nor lactic acidosis per se are likely predominant causative factors in diaphragmatic fatigue in this population, at least at the level of Sa,O2 tested. Rather, this result leads us to hypothesize that blood flow competition with the legs is an important contributor to diaphragmatic fatigue in heavy exercise, assuming that higher leg work required greater leg blood flow. PMID

  7. Exercise-induced cardiac performance in autoimmune (type 1) diabetes is associated with a decrease in myocardial diacylglycerol.

    PubMed

    Loganathan, Rajprasad; Novikova, Lesya; Boulatnikov, Igor G; Smirnova, Irina V

    2012-09-01

    One of the fundamental biochemical defects underlying the complications of diabetic cardiovascular system is elevation of diacylglycerol (DAG) and its effects on protein kinase C (PKC) signaling. It has been noted that exercise training attenuates poor cardiac performance in Type 1 diabetes. However, the role of PKC signaling in exercise-induced alleviation of cardiac abnormalities in diabetes is not clear. We investigated the possibility that exercise training modulates PKC-βII signaling to elicit its beneficial effects on the diabetic heart. bio-breeding diabetic resistant rats, a model reminiscent of Type 1 diabetes in humans, were randomly assigned to four groups: 1) nonexercised nondiabetic (NN); 2) nonexercised diabetic (ND); 3) exercised nondiabetic; and 4) exercised diabetic. Treadmill training was initiated upon the onset of diabetes. At the end of 8 wk, left ventricular (LV) hemodynamic assessment revealed compromised function in ND compared with the NN group. LV myocardial histology revealed increased collagen deposition in ND compared with the NN group, while electron microscopy showed a reduction in the viable mitochondrial fraction. Although the PKC-βII levels and activity were unchanged in the diabetic heart, the DAG levels were increased. With exercise training, the deterioration of LV structure and function in diabetes was attenuated. Notably, improved cardiac performance in training was associated with a decrease in myocardial DAG levels in diabetes. Exercise-induced benefits on cardiac performance in diabetes may be mediated by prevention of an increase in myocardial DAG levels. PMID:22797313

  8. Acute Exercise-Induced Mitochondrial Stress Triggers an Inflammatory Response in the Myocardium via NLRP3 Inflammasome Activation with Mitophagy

    PubMed Central

    Li, Haiying; Miao, Weiguo; Ma, Jingfen; Xv, Zhen; Li, Jianyu; Zhang, Yong; Ji, Li Li

    2016-01-01

    Increasing evidence has indicated that acute strenuous exercise can induce a range of adverse reactions including oxidative stress and tissue inflammation. However, little is currently known regarding the mechanisms that underlie the regulation of the inflammatory response in the myocardium during acute heavy exercise. This study evaluated the mitochondrial function, NLRP3 inflammasome activation, and mitochondrial autophagy-related proteins to investigate the regulation and mechanism of mitochondrial stress regarding the inflammatory response of the rat myocardium during acute heavy exercise. The results indicated that the mitochondrial function of the myocardium was adaptively regulated to meet the challenge of stress during acute exercise. The exercise-induced mitochondrial stress also enhanced ROS generation and triggered an inflammatory reaction via the NLRP3 inflammasome activation. Moreover, the mitochondrial autophagy-related proteins including Beclin1, LC3, and Bnip3 were all significantly upregulated during acute exercise, which suggests that mitophagy was stimulated in response to the oxidative stress and inflammatory response in the myocardium. Taken together, our data suggest that, during acute exercise, mitochondrial stress triggers the rat myocardial inflammatory response via NLRP3 inflammasome activation and activates mitophagy to minimize myocardial injury. PMID:26770647

  9. [Two cases of food-dependent exercise-induced anaphylaxis difficult to evoke symptoms by provocation test].

    PubMed

    Morimoto, Kenichi; Sanada, Seiko; Hara, Takeshi; Hide, Michihiro

    2006-11-01

    We report two cases of food-dependent exercise-induced anaphylaxis (FDEIA), which were hardly induced by provocation test in the hospital. Case 1: A 28-years-old Japanese female suffers repeated episodes of sternutation, nasal discharge and edema of eyelids after wheat ingestion of wheat followed by exercise. Case 2: A 14-years-old Japanese male suffers repeated episodes of wheal formation on whole body and dyspnea after lunch containing apple followed by exercise. Both of them had never developed symptoms by either ingestion or exercise alone. Provocation tests were performed on admission by combinations of the ingestion of suspected foods, exercise, and aspirin, but no symptoms were reproduced by any combination of them. After discharge, case 1 reproduced symptoms during exercise after the ingestion of wheat under prostration and cold climate. Case 2 reproduced symptoms during exercise after ingestion of apple when he suffered from common cold. Warm and comfortable condition in admission may make it harder to evoke symptoms by the provocation test. Frigidity, cold, prostration, and stress should be reckoned with in the provocation test to improve the accuracy of diagnosis for FDEIA. PMID:17159435

  10. Increased uptake of 18F-fluorodeoxyglucose in postischemic myocardium of patients with exercise-induced angina

    SciTech Connect

    Camici, P.; Araujo, L.I.; Spinks, T.; Lammertsma, A.A.; Kaski, J.C.; Shea, M.J.; Selwyn, A.P.; Jones, T.; Maseri, A.

    1986-07-01

    Regional myocardial perfusion and exogenous glucose uptake were assessed with rubidium-82 (82Rb) and 18F-2-fluoro-2-deoxyglucose (FDG) in 10 normal volunteers and 12 patients with coronary artery disease and stable angina pectoris by means of positron emission tomography. In patients at rest, the myocardial uptake of /sup 82/Rb and FDG did not differ significantly from that measured in normal subjects. The exercise test performed within the positron camera in eight patients produced typical chest pain and ischemic electrocardiographic changes in all. In each of the eight patients a region of reduced cation uptake was demonstrated in the /sup 82/Rb scan recorded at peak exercise, after which uptake of /sup 82/Rb returned to the control value 5 to 14 min after the end of the exercise. In these patients, FDG was injected in the recovery phase when all the variables that were altered during exercise, including regional myocardial /sup 82/Rb uptake, had returned to control values. In all but one patient, FDG accumulation in the regions of reduced /sup 82/Rb uptake during exercise was significantly higher than that in the nonischemic regions, i.e., the ones with a normal increment of /sup 82/Rb uptake on exercise. In the nonischemic areas, FDG uptake was not significantly different from that found in normal subjects after exercise. In conclusion, myocardial glucose transport and phosphorylation seem to be enhanced in the postischemic myocardium of patients with exercise-induced ischemia.

  11. Prevalence and Associated Clinical Characteristics of Exercise-Induced ST-Segment Elevation in Lead aVR

    PubMed Central

    Pitcher, Ian; Fordyce, Christopher B.; Yousefi, Masoud; Yeo, Tee Joo; Ignaszewski, Andrew; Isserow, Saul; Chan, Sammy; Ramanathan, Krishnan; Taylor, Carolyn M.

    2016-01-01

    Background Exercise-induced ST-segment elevation (STE) in lead aVR may be an important indicator of prognostically important coronary artery disease (CAD). However, the prevalence and associated clinical features of exercise-induced STE in lead aVR among consecutive patients referred for exercise stress electrocardiography (ExECG) is unknown. Methods All consecutive patients receiving a Bruce protocol ExECG for the diagnosis of CAD at a tertiary care academic center were included over a two-year period. Clinical characteristics, including results of coronary angiography, were compared between patients with and without exercise-induced STE in lead aVR. Results Among 2227 patients undergoing ExECG, exercise-induced STE ≥1.0mm in lead aVR occurred in 3.4% of patients. Patients with STE in lead aVR had significantly lower Duke Treadmill Scores (DTS) (-0.5 vs. 7.0, p<0.01) and a higher frequency of positive test results (60.2% vs. 7.3%, p<0.01). Furthermore, patients with STE in lead aVR were more likely to undergo subsequent cardiac catheterization than those without STE in lead aVR (p<0.01, odds ratio = 4.2). Conclusions Among patients referred for ExECG for suspected CAD, exercise-induced STE in lead aVR was associated with a higher risk DTS, an increased likelihood of a positive ExECG, and referral for subsequent coronary angiography. These results suggest that exercise-induced STE in lead aVR may represent a useful ECG feature among patients undergoing ExECG in the risk stratification of patients. PMID:27467388

  12. Level of dietary protein does not impact whole body protein turnover during an exercise induced energy deficit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: This study examined the effect of a high protein diet on whole body protein turnover during an exercise-induced energy deficit. A sustained energy deficit induced by energy intake restriction increases protein catabolism which can cause lean-body mass loss. A high-protein diet has be...

  13. Physical exercise in overweight to obese individuals induces metabolic- and neurotrophic-related structural brain plasticity

    PubMed Central

    Mueller, Karsten; Möller, Harald E.; Horstmann, Annette; Busse, Franziska; Lepsien, Jöran; Blüher, Matthias; Stumvoll, Michael; Villringer, Arno; Pleger, Burkhard

    2015-01-01

    Previous cross-sectional studies on body-weight-related alterations in brain structure revealed profound changes in the gray matter (GM) and white matter (WM) that resemble findings obtained from individuals with advancing age. This suggests that obesity may lead to structural brain changes that are comparable with brain aging. Here, we asked whether weight-loss-dependent improved metabolic and neurotrophic functioning parallels the reversal of obesity-related alterations in brain structure. To this end we applied magnetic resonance imaging (MRI) together with voxel-based morphometry and diffusion-tensor imaging in overweight to obese individuals who participated in a fitness course with intensive physical training twice a week over a period of 3 months. After the fitness course, participants presented, with inter-individual heterogeneity, a reduced body mass index (BMI), reduced serum leptin concentrations, elevated high-density lipoprotein-cholesterol (HDL-C), and alterations of serum brain-derived neurotrophic factor (BDNF) concentrations suggesting changes of metabolic and neurotrophic function. Exercise-dependent changes in BMI and serum concentration of BDNF, leptin, and HDL-C were related to an increase in GM density in the left hippocampus, the insular cortex, and the left cerebellar lobule. We also observed exercise-dependent changes of diffusivity parameters in surrounding WM structures as well as in the corpus callosum. These findings suggest that weight-loss due to physical exercise in overweight to obese participants induces profound structural brain plasticity, not primarily of sensorimotor brain regions involved in physical exercise, but of regions previously reported to be structurally affected by an increased body weight and functionally implemented in gustation and cognitive processing. PMID:26190989

  14. Identification and partial characterization of an exercise-induced neutrophil chemotactic factor in bronchial asthma.

    PubMed Central

    Lee, T H; Nagy, L; Nagakura, T; Walport, M J; Kay, A B

    1982-01-01

    A heat-stable neutrophil chemotactic factor (NCF) has been identified in the serum of 13 atopic asthmatic subjects after treadmill exercise. Peak activity was detected at 10 min and returned to prechallenge values by 1 h. No NCF activity was detected in the sera of three nonasthmatic atopic or four normal nonatopic individuals performing the same task. NCF produced by exercise (NCFEX) had a similar time-course of release to NCF provoked by specific antigen (NCFAG). The appearance of circulating NCFEX and NCFAG closely paralleled the fall in peak expiratory flow rate/forced expiratory volume in 1 s (PEFR/FEV1). Histamine challenge in atopic asthmatics at concentrations giving a comparable change in PEFR/FEV1 to that evoked by exercise or inhaled antigen was not associated with the appearance of circulating NCF. In seven subjects NCFEX release was inhibited by prior administration of disodium cromoglycate. NCFEX and NCFAG eluted as single peaks of activity when applied separately to columns of Sephadex G-200, and both were an estimated 750,000 daltons. NCFEX and NCFAG also eluted as single peaks of activity, at between 0.15 and 0.30 M NaCl, following anion exchange chromatography on DEAE-Sephacel (pH 7.8). The isoelectric points of NCFEX and NCFAG were virtually identical (between pH 6.0 and 6.5) as determined by chromatofocusing on Polybuffer Exchanger 94. The activities of NCFEX and NCFAG were substantially reduced, in both a time- and dose-dependent fashion, after incubation with trypsin and chymotrypsin. Partially purified NCFEX and NCFAG promoted both stimulated random migration (chemokinesis) as well as directional migration (chemotaxis). These experiments indicate that NCFEX and NCFAG might be identical substances and raise the possibility that mediators by hypersensitivity are released during exercise-induced asthma in atopic subjects. PMID:7076852

  15. Exercise Training-Induced Adaptations Associated with Increases in Skeletal Muscle Glycogen Content

    PubMed Central

    Manabe, Yasuko; Gollisch, Katja S.C.; Holton, Laura; Kim, Young–Bum; Brandauer, Josef; Fujii, Nobuharu L.; Hirshman, Michael F.; Goodyear, Laurie J.

    2012-01-01

    Chronic exercise training results in numerous skeletal muscle adaptations, including increases in insulin sensitivity and glycogen content. To understand the mechanism for increased muscle glycogen, we studied the effects of exercise training on glycogen regulatory proteins in rat skeletal muscle. Female Sprague Dawley rats performed voluntary wheel running for 1, 4, or 7 weeks. After 7 weeks of training, insulin-stimulated glucose uptake was increased in epitrochlearis muscle. Compared to sedentary control rats, muscle glycogen did not change after 1 week of training, but increased significantly after 4 and 7 weeks. The increases in muscle glycogen were accompanied by elevated glycogen synthase activity and protein expression. To assess the regulation of glycogen synthase, we examined its major activator, protein phosphatase 1 (PP1), and its major deactivator, glycogen synthase kinase 3 (GSK3). Consistent with glycogen synthase activity, PP1 activity was unchanged after 1 week of training but significantly increased after 4 and 7 weeks of training. Protein expression of RGL(GM), another regulatory PP1 subunit, significantly decreased after 4 and 7 weeks of training. Unlike PP1, GSK3 phosphorylation did not follow the pattern of glycogen synthase activity. The ~40% decrease in GSK-3α phosphorylation after 1 week of exercise training persisted until 7 weeks and may function as a negative feedback to elevated glycogen. Our findings suggest that exercise training-induced increases in muscle glycogen content could be regulated by multiple mechanisms including enhanced insulin sensitivity, glycogen synthase expression, allosteric activation of glycogen synthase and PP1activity. PMID:23206309

  16. The Acute Effect of Local Vibration As a Recovery Modality from Exercise-Induced Increased Muscle Stiffness.

    PubMed

    Pournot, Hervé; Tindel, Jérémy; Testa, Rodolphe; Mathevon, Laure; Lapole, Thomas

    2016-03-01

    Exercise involving eccentric muscle contractions is known to decrease range of motion and increase passive muscle stiffness. This study aimed at using ultrasound shear wave elastography to investigate acute changes in biceps brachii passive stiffness following intense barbell curl exercise involving both concentric and eccentric contractions. The effect of local vibration (LV) as a recovery modality from exercise-induced increased stiffness was further investigated. Eleven subjects performed 4 bouts of 10 bilateral barbell curl movements at 70% of the one-rep maximal flexion force. An arm-to-arm comparison model was then used with one arm randomly assigned to the passive recovery condition and the other arm assigned to the LV recovery condition (10 min of 55-Hz vibration frequency and 0.9-mm amplitude). Biceps brachii shear elastic modulus measurements were performed prior to exercise (PRE), immediately after exercise (POST-EX) and 5 min after the recovery period (POST-REC). Biceps brachii shear elastic modulus was significantly increased at POST-EX (+53 ± 48%; p < 0.001) and POST-REC (+31 ± 46%; p = 0.025) when compared to PRE. No differences were found between passive and LV recovery (p = 0.210). LV as a recovery strategy from exercise-induced increased muscle stiffness was not beneficial, probably due to an insufficient mechanical action of vibrations. Key pointsBouts of barbell curl exercise induce an immediate increased passive stiffness of the biceps brachii muscle, as evidenced by greater shear elastic modulus measured by supersonic shear imaging.The administration of a vibratory massage did not reduce this acute exercise-induced increased stiffness. PMID:26957937

  17. The Acute Effect of Local Vibration As a Recovery Modality from Exercise-Induced Increased Muscle Stiffness

    PubMed Central

    Pournot, Hervé; Tindel, Jérémy; Testa, Rodolphe; Mathevon, Laure; Lapole, Thomas

    2016-01-01

    Exercise involving eccentric muscle contractions is known to decrease range of motion and increase passive muscle stiffness. This study aimed at using ultrasound shear wave elastography to investigate acute changes in biceps brachii passive stiffness following intense barbell curl exercise involving both concentric and eccentric contractions. The effect of local vibration (LV) as a recovery modality from exercise-induced increased stiffness was further investigated. Eleven subjects performed 4 bouts of 10 bilateral barbell curl movements at 70% of the one-rep maximal flexion force. An arm-to-arm comparison model was then used with one arm randomly assigned to the passive recovery condition and the other arm assigned to the LV recovery condition (10 min of 55-Hz vibration frequency and 0.9-mm amplitude). Biceps brachii shear elastic modulus measurements were performed prior to exercise (PRE), immediately after exercise (POST-EX) and 5 min after the recovery period (POST-REC). Biceps brachii shear elastic modulus was significantly increased at POST-EX (+53 ± 48%; p < 0.001) and POST-REC (+31 ± 46%; p = 0.025) when compared to PRE. No differences were found between passive and LV recovery (p = 0.210). LV as a recovery strategy from exercise-induced increased muscle stiffness was not beneficial, probably due to an insufficient mechanical action of vibrations. Key points Bouts of barbell curl exercise induce an immediate increased passive stiffness of the biceps brachii muscle, as evidenced by greater shear elastic modulus measured by supersonic shear imaging. The administration of a vibratory massage did not reduce this acute exercise-induced increased stiffness. PMID:26957937

  18. Treadmill exercise improves short-term memory by enhancing neurogenesis in amyloid beta-induced Alzheimer disease rats

    PubMed Central

    Kim, Bo-Kyun; Shin, Mal-Soon; Kim, Chang-Ju; Baek, Sang-Bin; Ko, Yeong-Chan; Kim, Young-Pyo

    2014-01-01

    Alzheimer’s disease is one of the most devastating neurodegenerative disorders, and this disease is characterized by severe memory impairment and decline of cognition. Hippocampal neurons are vulnerable to injury induced by Alzheimer’s disease. Physical exercise is known to promote cell survival and functional recovery after brain injuries. In the present study, we investigated the effects of treadmill exercise on short-term memory in relation with neurogenesis in the rats with amyloid β25–35 (Aβ25–35)-induced Alzheimer’s disease. The rat model of Alzheimer’s disease was induced by the intracerebroventricular (ICV) injection of Aβ25–35, using a stereotaxic instrument. The rats in the exercise group were forced to run on a treadmill for 30 min once daily for 4 consecutive weeks, starting 2 days after Aβ25–35 injection. Presently, short-term memory was deteriorated and apical dendritic length in the hippocampus was shortened in the hippocampus by Aβ25–35 injection. In contrast, treadmill exercise alleviated memory impairment and increased apical dendritic length in the Aβ25–35-injected rats. Neurogenesis and brain-derived neurotorphic factor (BDNF) and tyrosine kinase B (trkB) in the hippocampal dentate gyrus were decreased by Aβ25–35 injection. Treadmill exercise increased neurogenesis and expressions of BDNF and trkB expressions. The present study shows that treadmill exercise may provide therapeutic value for the alleviating symptoms of Alzheimer’s disease. PMID:24678498

  19. Treadmill exercise improves motor coordination through ameliorating Purkinje cell loss in amyloid beta23-35-induced Alzheimer's disease rats.

    PubMed

    Lee, Jae-Min; Shin, Mal-Soon; Ji, Eun-Sang; Kim, Tae-Woon; Cho, Han-Sam; Kim, Chang-Ju; Jang, Myung-Soo; Kim, Tae-Wook; Kim, Bo-Kyun; Kim, Dong-Hee

    2014-10-01

    Alzheimer's disease (AD) is a most common age-related neurodegenerative disease. AD is characterized by a progressive loss of neurons causing cognitive dysfunction. The cerebellum is closely associated with integration of movement, including motor coordination, control, and equilibrium. In the present study, we evaluated the effect of tread-mill exercise on the survival of Purkinje neurons in relation with reactive astrocyte in the cerebellum using Aβ25-35-induced AD rats. AD was induced by a bilateral intracerebroventricular (ICV) injection of Aβ25-35. The rats in the exercise groups were forced to run on a motorized treadmill for 30 min once a day for 4 weeks, starting 2 days after Aβ25-35 injection. In the present results, ICV injection of Aβ25-35 deteriorated motor coordination and balance. The number of calbindin-positive cells in the cerebellar vermis was decreased and glial fibrillary acidic protein (GFAP) expression in the cerebellar vermis was increased in the Aβ25-35-induced AD rats. Treadmill exercise improved motor coordination and balance. Treadmill exercise increased the number of Purkinje neurons and suppressed GFAP expression in the cerebellar vermis. The present study demonstrated that treadmill exercises alleviated dysfunction of motor coordination and balance by reduction of Purkinje cell loss through suppressing reactive astrocytes in the cerebellum of AD rats. The present study provides the possibility that treadmill exercise might be an important therapeutic strategy for the symptom improvement of AD patients. PMID:25426461

  20. Effect of Regular Exercise on Inflammation Induced by Drug-resistant Staphylococcus aureus 3089 in ICR mice

    PubMed Central

    Lee, Jong-Kook; Luchian, Tudor; Park, Yoonkyung

    2015-01-01

    Obesity is often associated with irregular dietary habits and reduced physical activity. Regular exercise induces a metabolic response that includes increased expression of various cytokines, signaling proteins and hormones, and reduced adipocyte size. In this study, mice performed a swimming exercise for 10 min/day, 5 days/week for 3 weeks. We then investigated the effect of this exercise regimen on inflammation induced by infection with drug-resistant Staphylococcus aureus strain 3089 (DRSA). In humans, DRSA causes dermatitis and pneumonitis. Similarly, DRSA induced inflammatory pneumonitis in both no-exercise (No-EX) and swim-trained (SW-EX) ICR mice. Regular exercise increased levels of the pro-inflammatory cytokines TNF-α and IL-1β and nitric oxide in both serum and whole lung tissue in SW-EX, as compared to No-EX control mice. Moreover, levels of the antimicrobial peptide cathelicidin were significantly increased in visceral adipose tissue and whole lung tissue in the SW-EX group, and this was accompanied by a reduction in the size of visceral adipocytes. In addition, levels of the inflammation marker peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) were not increased in the lung tissue of SW-EX mice. These findings suggest that in these model mice, regular exercise strengthens immune system responses, potentially preventing or mitigating infectious disease. PMID:26542343

  1. Attenuated exercise induced hyperaemia with age: mechanistic insight from passive limb movement

    PubMed Central

    McDaniel, John; Hayman, Melissa A; Ives, Steve; Fjeldstad, Anette S; Trinity, Joel D; Wray, D Walter; Richardson, Russell S

    2010-01-01

    The influence of age on the central and peripheral contributors to exercise-induced hyperaemia is unclear. Utilizing a reductionist approach, we compared the peripheral and central haemodynamic responses to passive limb movement (exercise without an increase in metabolism) in 11 old (71 ± 9 years of age s.d.) and 11 young (24 ± 2 years of age) healthy subjects. Cardiac output (CO), heart rate (HR), stroke volume (SV), mean arterial pressure (MAP), and femoral blood flow of the passively moved and control legs were evaluated second-by-second during 2 min of passive knee extension at a rate of 1 Hz. Compared to the young, the old group exhibited a significantly attenuated increase in HR (7 ± 4%vs. 13 ± 7%s.d.), CO (10 ± 6%vs. 18 ± 8%) and femoral blood flow in the passively moved (123 ± 55%vs. 194 ± 57%) and control legs (47 ± 43%vs. 77 ± 96%). In addition, the change in vascular conductance in the passively moving limb was also significantly attenuated in the old (2.4 ± 1.2 ml min−1 mmHg−1) compared to the young (4.3 ± 1.7 ml min−1 mmHg−1). In both groups all main central and peripheral changes that occurred at the onset of passive knee extension were transient, lasting only 45 s. In a paradigm where metabolism does not play a role, these data reveal that both central and peripheral haemodynamic mechanisms are likely to be responsible for the 30% reduction in exercise-induced hyperaemia with age. PMID:20876201

  2. Exercise-induced differential changes in gene expression among arterioles of skeletal muscles of obese rats.

    PubMed

    Laughlin, M Harold; Padilla, Jaume; Jenkins, Nathan T; Thorne, Pamela K; Martin, Jeffrey S; Rector, R Scott; Akter, Sadia; Davis, J Wade

    2015-09-15

    Using next-generation, transcriptome-wide RNA sequencing (RNA-Seq) technology we assessed the effects of exercise training on transcriptional profiles in skeletal muscle arterioles isolated from the soleus and gastrocnemius muscles of Otsuka Long Evans Tokushima Fatty (OLETF) rats that underwent an endurance exercise training program (EX; n = 13), interval sprint training program (SPRINT; n = 14), or remained sedentary (Sed; n = 12). We hypothesized that the greatest effects of exercise would be in the gastrocnemius arterioles. Results show that EX caused the largest number of changes in gene expression in the soleus and white gastrocnemius 2a arterioles with little to no changes in the feed arteries. In contrast, SPRINT caused substantial changes in gene expression in the feed arteries. IPA canonical pathway analysis revealed 18 pathways with significant changes in gene expression when analyzed across vessels and revealed that EX induces increased expression of the following genes in all arterioles examined: Shc1, desert hedgehog protein (Dhh), adenylate cyclase 4 (Adcy4), G protein binding protein, alpha (Gnat1), and Bcl2l1 and decreased expression of ubiquitin D (Ubd) and cAMP response element modulator (Crem). EX increased expression of endothelin converting enzyme (Ece1), Hsp90b, Fkbp5, and Cdcl4b in four of five arterioles. SPRINT had effects on expression of Crem, Dhh, Bcl2l1, and Ubd that were similar to EX. SPRINT also increased expression of Nfkbia, Hspa5, Tubb 2a and Tubb 2b, and Fkbp5 in all five arterioles and increased expression of Gnat1 in all but the soleus second-order arterioles. Many contractile and/or structural protein genes were increased by SPRINT in the gastrocnemius feed artery, but the same genes exhibited decreased expression in red gastrocnemius arterioles. We conclude that training-induced changes in arteriolar gene expression patterns differ by muscle fiber type composition and along the arteriolar tree. PMID:26183477

  3. Glycopyrrolate abolishes the exercise-induced increase in cerebral perfusion in humans.

    PubMed

    Seifert, Thomas; Fisher, James P; Young, Colin N; Hartwich, Doreen; Ogoh, Shigehiko; Raven, Peter B; Fadel, Paul J; Secher, Niels H

    2010-10-01

    Brain blood vessels contain muscarinic receptors that are important for cerebral blood flow (CBF) regulation, but whether a cholinergic receptor mechanism is involved in the exercise-induced increase in cerebral perfusion or affects cerebral metabolism remains unknown. We evaluated CBF and cerebral metabolism (from arterial and internal jugular venous O(2), glucose and lactate differences), as well as the middle cerebral artery mean blood velocity (MCA V(mean); transcranial Doppler ultrasound) during a sustained static handgrip contraction at 40% of maximal voluntary contraction (n = 9) and the MCA V(mean) during ergometer cycling (n = 8). Separate, randomized and counterbalanced trials were performed in control (no drug) conditions and following muscarinic cholinergic receptor blockade by glycopyrrolate. Glycopyrrolate increased resting heart rate from approximately 60 to approximately 110 beats min(-1) (P < 0.01) and cardiac output by approximately 40% (P < 0.05), but did not affect mean arterial pressure. The central cardiovascular responses to exercise with glycopyrrolate were similar to the control responses, except that cardiac output did not increase during static handgrip with glycopyrrolate. Glycopyrrolate did not significantly affect cerebral metabolism during static handgrip, but a parallel increase in MCA V(mean) (approximately 16%; P < 0.01) and CBF (approximately 12%; P < 0.01) during static handgrip, as well as the increase in MCA V(mean) during cycling (approximately 15%; P < 0.01), were abolished by glycopyrrolate (P < 0.05). Thus, during both cycling and static handgrip, a cholinergic receptor mechanism is important for the exercise-induced increase in cerebral perfusion without affecting the cerebral metabolic rate for oxygen. PMID:20660020

  4. Treadmill exercise alleviates stress-induced impairment of social interaction through 5-hydroxytryptamine 1A receptor activation in rats

    PubMed Central

    Kim, Tae-Woon; Lim, Baek-Vin; Kim, Kijeong; Seo, Jin-Hee; Kim, Chang-Ju

    2015-01-01

    Brain-derived neurotrophic factor (BDNF) and its receptors tyrosine kinase B (trkB), and cyclic adenosine monophosphate response element binding protein (CREB) have been suggested as the neurobiological risk factors causing depressive disorder. Serotonin (5-hydroxytryptamine, 5-HT) plays an important role in the pathogenesis of depression. We in-vestigated the effect of treadmill exercise on social interaction in relation with BDNF and 5-HT expressions following stress in rats. Stress was induced by applying inescapable 0.2 mA electric foot shock to the rats for 7 days. The rats in the exercise groups were forced to run on a motorized treadmill for 30 min once a day for 4 weeks. Social interaction test and western blot for BDNF, TrkB, pCREB, and 5-HT1A in the hippocampus were performed. The results indicate that the spend time with unfamiliar partner was decreased by stress, in contrast, treadmill exercise increased the spending time in the stress-induced rats. Expressions of BDNF, TrkB, and pCREB were decreased by stress, in contrast, treadmill exercise enhanced expressions of BDNF, TrkB, and pCREB in the stress-induced rats. In addition, 5-HT1A receptor expression was de-creased by stress, in contrast, treadmill exercise enhanced 5-HT1A expression in the stress-induced rats. In the present study, treadmill exercise alleviated stress-induced social interaction impairment through enhancing hippocampal plasticity and serotonergic function in the hippocampus. These effects of treadmill exercise are achieved through 5-HT1A receptor activation. PMID:26331133

  5. Treadmill exercise alleviates stress-induced impairment of social interaction through 5-hydroxytryptamine 1A receptor activation in rats.

    PubMed

    Kim, Tae-Woon; Lim, Baek-Vin; Kim, Kijeong; Seo, Jin-Hee; Kim, Chang-Ju

    2015-08-01

    Brain-derived neurotrophic factor (BDNF) and its receptors tyrosine kinase B (trkB), and cyclic adenosine monophosphate response element binding protein (CREB) have been suggested as the neurobiological risk factors causing depressive disorder. Serotonin (5-hydroxytryptamine, 5-HT) plays an important role in the pathogenesis of depression. We in-vestigated the effect of treadmill exercise on social interaction in relation with BDNF and 5-HT expressions following stress in rats. Stress was induced by applying inescapable 0.2 mA electric foot shock to the rats for 7 days. The rats in the exercise groups were forced to run on a motorized treadmill for 30 min once a day for 4 weeks. Social interaction test and western blot for BDNF, TrkB, pCREB, and 5-HT1A in the hippocampus were performed. The results indicate that the spend time with unfamiliar partner was decreased by stress, in contrast, treadmill exercise increased the spending time in the stress-induced rats. Expressions of BDNF, TrkB, and pCREB were decreased by stress, in contrast, treadmill exercise enhanced expressions of BDNF, TrkB, and pCREB in the stress-induced rats. In addition, 5-HT1A receptor expression was de-creased by stress, in contrast, treadmill exercise enhanced 5-HT1A expression in the stress-induced rats. In the present study, treadmill exercise alleviated stress-induced social interaction impairment through enhancing hippocampal plasticity and serotonergic function in the hippocampus. These effects of treadmill exercise are achieved through 5-HT1A receptor activation. PMID:26331133

  6. Heat and exercise acclimation increases intracellular levels of Hsp72 and inhibits exercise-induced increase in intracellular and plasma Hsp72 in humans

    PubMed Central

    Magalhães, Flávio de Castro; Amorim, Fabiano Trigueiro; Passos, Renata L. Freitas; Fonseca, Michele Atalla; Oliveira, Kenya Paula Moreira; Lima, Milene Rodrigues Malheiros; Guimarães, Juliana Bohen; Ferreira-Júnior, João Batista; Martini, Angelo R. P.; Lima, Nilo R. V.; Soares, Danusa Dias; Oliveira, Edilamar Menezes

    2010-01-01

    In order to verify the effects of heat and exercise acclimation (HA) on resting and exercise-induced expression of plasma and leukocyte heat shock protein 72 (Hsp72) in humans, nine healthy young male volunteers (25.0 ± 0.7 years; 80.5 ± 2.0 kg; 180 ± 2 cm, mean ± SE) exercised for 60 min in a hot, dry environment (40 ± 0°C and 45 ± 0% relative humidity) for 11 days. The protocol consisted of running on a treadmill using a controlled hyperthermia technique in which the work rate was adjusted to elevate the rectal temperature by 1°C in 30 min and maintain it elevated for another 30 min. Before and after the HA, the volunteers performed a heat stress test (HST) at 50% of their individual maximal power output for 90 min in the same environment. Blood was drawn before (REST), immediately after (POST) and 1 h after (1 h POST) HST, and plasma and leukocytes were separated and stored. Subjects showed expected adaptations to HA: reduced exercise rectal and mean skin temperatures and heart rate, and augmented sweat rate and exercise tolerance. In HST1, plasma Hsp72 increased from REST to POST and then returned to resting values 1 h POST (REST: 1.11 ± 0.07, POST: 1.48 ± 0.10, 1 h POST: 1.22 ± 0.11 ng mL−1; p < 0.05). In HST2, there was no change in plasma Hsp72 (REST: 0.94 ± 0.08, POST: 1.20 ± 0.15, 1 h POST: 1.17 ± 0.16 ng mL−1; p > 0.05). HA increased resting levels of intracellular Hsp72 (HST1: 1 ± 0.02 and HST2: 4.2 ± 1.2 density units, p < 0.05). Exercise-induced increased intracellular Hsp72 expression was observed on HST1 (HST1: REST, 1 ± 0.02 vs. POST, 2.9 ± 0.9 density units, mean ± SE, p < 0.05) but was inhibited on HST2 (HST2: REST, 4.2 ± 1.2 vs. POST, 4.4 ± 1.1 density units, p > 0.05). Regression analysis showed that the lower the pre-exercise expression of intracellular Hsp72, the higher the exercise-induced increase (R = −0

  7. Osteoblastic cell response on biphasic fluorhydroxyapatite/strontium-substituted hydroxyapatite coatings.

    PubMed

    Yin, Ping; Feng, Fang Fang; Lei, Ting; Zhong, Xiao Huan; Jian, Xin Chun

    2014-03-01

    Fluorhydroxyapatite/strontium-substituted hydroxyapatite (FHA/SrHA) biphasic coatings with F and Sr elements incorporated simultaneously into one coating layer were prepared on titanium substrate via colloidal sol-gel method. The bioactivity of the as-prepared FHA/SrHA biphasic coatings was evaluated in vitro by immersion in simulated body fluid (SBF). All the biphasic coatings exhibited great ability to induce apatite precipitation on their surfaces. In vitro cell responses were evaluated using osteoblast-like MG63 cells in terms of cell proliferation and differentiation (alkaline phosphatase activity and osteocalcin level). The biphasic coatings show significantly positive effects on the viability and functional activity of osteoblastic cells with clear evidence that an optimum SrHA amount dose exists, indicating that the coexistence of FHA and SrHA had a synergistic stimulatory effect. This finding suggests the potential use of this colloidal sol-gel derived FHA/SrHA biphasic coatings for hard tissue applications. PMID:23533202

  8. Myocardial accumulation and localization of the inducible 70-kDa heat shock protein, Hsp70, following exercise

    PubMed Central

    Wolff, S.; Noble, E. G.

    2012-01-01

    Exercise increases the 70-kDa heat shock protein (Hsp70) in the myocardium, and this exercise-induced increase is associated with significantly improved cardiac recovery following insult. However, while heat shock has been shown to elevate Hsp70 primarily in the cardiac vasculature of the myocardium, the localization following exercise is unknown. Male Sprague-Dawley rats performed continuous treadmill running at 30 m/min for 60 min (2% incline) on either 1 or 5 consecutive days. At 30 min and 24 h following exercise, hearts were extirpated, and the left ventricle was isolated, OCT-cork mounted, and sectioned for immunofluorescent analysis. Whereas immunofluorescent analysis revealed little to no Hsp70 in control hearts and 30 min postexercise, the accumulation of Hsp70 24 h after a single exercise bout or 5 days of training was predominantly located in large blood vessels and, in particular, colocalized with a marker of smooth muscle. Furthermore, higher core temperatures attained during exercise led to more abundant accumulation in smaller vessels and the endothelium. It is concluded that the accumulation of myocardial Hsp70 following acute exercise predominantly occurs in a cell type-specific manner, such that changes in the cardiac vasculature account for much of the increase. This accumulation appears first in the smooth muscle of larger vessels and then increases in smaller vessels and the endothelium, as core temperature attained during exercise increases. This finding supports the observations after heat shock and further suggests that the vasculature is a primary target in exercise-induced cardioprotection. PMID:22773766

  9. Effects of Chemically Induced Ovarian Failure on Voluntary Wheel-Running Exercise and Cardiac Adaptation in Mice

    PubMed Central

    Perez, Jessica N; Chen, Hao; Regan, Jessica A; Emert, Ashlie; Constantopoulos, Eleni; Lynn, Melissa; Konhilas, John P

    2013-01-01

    The role of exercise in decreasing the risk of cardiovascular disease in postmenopausal women has not been studied sufficiently. Accordingly, we investigated the effect of voluntary wheel-running and forced treadmill exercise on cardiac adaptation in mice treated with 4-vinylcyclohexine diepoxide (VCD), which selectively accelerates the loss of primary and primordial follicles and results in a state that closely mimics human menopause. Two-month-old female C57BL/6 mice injected with VCD (160 mg/kg) for 20 consecutive days underwent ovarian failure by 60 to 90 d after injection. Responses to voluntary wheel running and treadmill exercise did not differ between VCD- and vehicle-treated 7-mo-old C57BL/6 or outbred B6C3F1 mice. Moreover, adaptive cardiac hypertrophy, hypertrophic marker expression, and skeletal muscle characteristics after voluntary cage-wheel exercise did not differ between VCD- and vehicle-treated mice. Because 5′ AMP-activated protein kinase (AMPK) is a key component for the maintenance of cardiac energy balance during exercise, we determined the effect of exercise and VCD-induced ovarian failure on the AMPK signaling axis in the heart. According to Western blotting, VCD treatment followed by voluntary cage-wheel exercise differently affected the upstream AMPK regulatory components AMPKα1 and AMPKα2. In addition, net downstream AMPK signaling was reduced after VCD treatment and exercise. Our data suggest that VCD did not affect exercise-induced cardiac hypertrophy but did alter cellular cardiac adaptation in a mouse model of menopause. PMID:23759526

  10. Effects of endotoxin induced lung injury and exercise in goats/sheep. Final report, 1 February 1992-2 June 1993

    SciTech Connect

    Mundie, T.G.

    1993-06-02

    This study was designed the effects of exercise performed on animals already injured with E. coli endotoxin. This would tell us whether exercise makes the lung injury worse. It would also tell us how much exercise performance is impaired. These studies were designed to give further insights into the underlying causes of acute lung injury. Premature termination of the study prevented completion of the research project. It appeared from the limited experimentation conducted that maximal exercise was impaired by endotoxin-induced lung injury. Conclusions regarding exacerbation of endotoxin-induced lung injury cannot be made.... Acute lung injury, Maximal exercise, Endotoxin.

  11. Biphasic decay of the Ca transient results from increased sarcoplasmic reticulum Ca leak

    PubMed Central

    Sankaranarayanan, Rajiv; Li, Yatong; Greensmith, David J.; Eisner, David A.

    2016-01-01

    Key points Ca leak from the sarcoplasmic reticulum through the ryanodine receptor (RyR) reduces the amplitude of the Ca transient and slows its rate of decay.In the presence of β‐adrenergic stimulation, RyR‐mediated Ca leak produces a biphasic decay of the Ca transient with a fast early phase and a slow late phase.Two forms of Ca leak have been studied, Ca‐sensitising (induced by caffeine) and non‐sensitising (induced by ryanodine) and both induce biphasic decay of the Ca transient.Only Ca‐sensitising leak can be reversed by traditional RyR inhibitors such as tetracaine.Ca leak can also induce Ca waves. At low levels of leak, waves occur. As leak is increased, first biphasic decay and then slowed monophasic decay is seen. The level of leak has major effects on the shape of the Ca transient. Abstract In heart failure, a reduction in Ca transient amplitude and contractile dysfunction can by caused by Ca leak through the sarcoplasmic reticulum (SR) Ca channel (ryanodine receptor, RyR) and/or decreased activity of the SR Ca ATPase (SERCA). We have characterised the effects of two forms of Ca leak (Ca‐sensitising and non‐sensitising) on calcium cycling and compared with those of SERCA inhibition. We measured [Ca2+]i with fluo‐3 in voltage‐clamped rat ventricular myocytes. Increasing SR leak with either caffeine (to sensitise the RyR to Ca activation) or ryanodine (non‐sensitising) had similar effects to SERCA inhibition: decreased systolic [Ca2+]i, increased diastolic [Ca2+]i and slowed decay. However, in the presence of isoproterenol, leak produced a biphasic decay of the Ca transient in the majority of cells while SERCA inhibition produced monophasic decay. Tetracaine reversed the effects of caffeine but not of ryanodine. When caffeine (1 mmol l−1) was added to a cell which displayed Ca waves, the wave frequency initially increased before waves disappeared and biphasic decay developed. Eventually (at higher caffeine concentrations), the

  12. Treadmill exercise alleviates prenatal noise stress-induced impairment of spatial learning ability through enhancing hippocampal neurogenesis in rat pups

    PubMed Central

    Kim, Tae-Woon; Shin, Mal-Soon; Park, Joon-Ki; Shin, Mi-Ai; Lee, Hee-Hyuk; Lee, Sam-Jun

    2013-01-01

    Stress alters brain cell properties and then disturbs cognitive processes, such as learning and memory. In this study, we investigated the effect of postnatal treadmill exercise on hippocampal neurogenesis and spatial learning ability of rat pups following prenatal noise stress. The impact of exercise intensity (mild-intensity exercise vs heavy-intensity exercise) was also compared. The pregnant rats in the stress-applied group were exposed to a 95 dB supersonic machine sound for 1 h once a day from the 15th day after mating until delivery. After birth, the rat pups in the exercise groups were made to run on a treadmill for 30 min once a day for 7 consecutive days, starting 4 weeks after birth. The spatial learning ability was tested using radial-arm maze task and hippocampal neurogenesis was determined by 5-bromo-2′-deoxyuridine (BrdU) immunohistochemistry. The rat pups born from the stress-applied maternal rats spent more time for the seeking of water and showed higher number of error in the radial-arm maze task compared to the control group. These rat pups showed suppressed neurogenesis in the hippocampus. In contrast, the rat pups performed postnatal treadmill exercise saved time for seeking of water and showed lower number of error compared to the stress-applied group. Postnatal treadmill exercise also enhanced neurogenesis in the hippocampus. The mild-intensity exercise showed more potent impact compared to the heavy-intensity exercise. The present results reveal that postnatal treadmill exercise lessens prenatal stress-induced deterioration of brain function in offspring. PMID:24282804

  13. Contribution of respiratory muscle blood flow to exercise-induced diaphragmatic fatigue in trained cyclists

    PubMed Central

    Vogiatzis, Ioannis; Athanasopoulos, Dimitris; Boushel, Robert; Guenette, Jordan A; Koskolou, Maria; Vasilopoulou, Maroula; Wagner, Harrieth; Roussos, Charis; Wagner, Peter D; Zakynthinos, Spyros

    2008-01-01

    We investigated whether the greater degree of exercise-induced diaphragmatic fatigue previously reported in highly trained athletes in hypoxia (compared with normoxia) could have a contribution from limited respiratory muscle blood flow. Seven trained cyclists completed three constant load 5 min exercise tests at inspired O2 fractions () of 0.13, 0.21 and 1.00 in balanced order. Work rates were selected to produce the same tidal volume, breathing frequency and respiratory muscle load at each (63 ± 1, 78 ± 1 and 87 ± 1% of normoxic maximal work rate, respectively). Intercostals and quadriceps muscle blood flow (IMBF and QMBF, respectively) were measured by near-infrared spectroscopy over the left 7th intercostal space and the left vastus lateralis muscle, respectively, using indocyanine green dye. The mean pressure time product of the diaphragm and the work of breathing did not differ across the three exercise tests. After hypoxic exercise, twitch transdiaphragmatic pressure fell by 33.3 ± 4.8%, significantly (P < 0.05) more than after both normoxic (25.6 ± 3.5% reduction) and hyperoxic (26.6 ± 3.3% reduction) exercise, confirming greater fatigue in hypoxia. Despite lower leg power output in hypoxia, neither cardiac output nor QMBF (27.6 ± 1.2 l min−1 and 100.4 ± 8.7 ml (100 ml)−1 min−1, respectively) were significantly different compared with normoxia (28.4 ± 1.9 l min−1 and 94.4 ± 5.2 ml (100 ml)−1 min−1, respectively) and hyperoxia (27.8 ± 1.6 l min−1 and 95.1 ± 7.8 ml (100 ml)−1 min−1, respectively). Neither IMBF was different across hypoxia, normoxia and hyperoxia (53.6 ± 8.5, 49.9 ± 5.9 and 52.9 ± 5.9 ml (100 ml)−1 min−1, respectively). We conclude that when respiratory muscle energy requirement is not different between normoxia and hypoxia, diaphragmatic fatigue is greater in hypoxia as intercostal muscle blood flow is not increased (compared with normoxia) to compensate for the reduction in , thus further compromising O2

  14. Exercise-Induced Splanchnic Hypoperfusion Results in Gut Dysfunction in Healthy Men

    PubMed Central

    van Wijck, Kim; Lenaerts, Kaatje; van Loon, Luc J. C.; Peters, Wilbert H. M.; Buurman, Wim A.; Dejong, Cornelis H. C.

    2011-01-01

    Background Splanchnic hypoperfusion is common in various pathophysiological conditions and often considered to lead to gut dysfunction. While it is known that physiological situations such as physical exercise also result in splanchnic hypoperfusion, the consequences of flow redistribution at the expense of abdominal organs remained to be determined. This study focuses on the effects of splanchnic hypoperfusion on the gut, and the relationship between hypoperfusion, intestinal injury and permeability during physical exercise in healthy men. Methods and Findings Healthy men cycled for 60 minutes at 70% of maximum workload capacity. Splanchnic hypoperfusion was assessed using gastric tonometry. Blood, sampled every 10 minutes, was analyzed for enterocyte damage parameters (intestinal fatty acid binding protein (I-FABP) and ileal bile acid binding protein (I-BABP)). Changes in intestinal permeability were assessed using sugar probes. Furthermore, liver and renal parameters were assessed. Splanchnic perfusion rapidly decreased during exercise, reflected by increased gapg-apCO2 from −0.85±0.15 to 0.85±0.42 kPa (p<0.001). Hypoperfusion increased plasma I-FABP (615±118 vs. 309±46 pg/ml, p<0.001) and I-BABP (14.30±2.20 vs. 5.06±1.27 ng/ml, p<0.001), and hypoperfusion correlated significantly with this small intestinal damage (rS = 0.59; p<0.001). Last of all, plasma analysis revealed an increase in small intestinal permeability after exercise (p<0.001), which correlated with intestinal injury (rS = 0.50; p<0.001). Liver parameters, but not renal parameters were elevated. Conclusions Exercise-induced splanchnic hypoperfusion results in quantifiable small intestinal injury. Importantly, the extent of intestinal injury correlates with transiently increased small intestinal permeability, indicating gut barrier dysfunction in healthy individuals. These physiological observations increase our knowledge of splanchnic hypoperfusion sequelae, and may help to

  15. Exercise induced changes in lymphocyte beta adrenergic receptors correlate with peak exercise heart rates in healthy trained and sedentary human subjects

    SciTech Connect

    Eisinger, M.; Engelmeier, R.; Glisson, S.; Scanlon, P.

    1986-03-05

    Lymphocyte beta adrenergic receptors (lymph BAR) increase after maximal multistage treadmill exercise (TME) presumably by externalization from intracellular vesicles. Nine healthy subjects underwent symptom limited TME by the Bruce protocol. Heart rate was measured at the end of each 3 minute stage. Plasma norepinephrine (NE), plasma epinephrine (EPI) and lymph BAR were measured at rest and at peak exercise. Catecholamines were determined by high performance liquid chromatography. Lymph BAR were measured by separating cells from 25cc of whole blood across a Ficoll-Hypaque density gradient and incubating membrane preparations with 7 dilutions of I/sup 125/ cyanopindolol in the presence or absence of 1..mu..M(-) propranolol in a total assay volume of 450 ..mu..l. BAR was standardized to Lowry-Peterson protein at rest and exercise. The relationship of maximum heart rate versus peak plasma NE, EPI and lymph BAR was analyzed by linear regression. The following conclusions were reached: (1) there is a significant correlation between exercise induced changes in lymph BAR and peak heart rate; (2) this relationship does not exist between peak plasma NE or EPI and peak heart rate.

  16. Physical Exercise Counteracts Stress-induced Upregulation of Melanin-concentrating Hormone in the Brain and Stress-induced Persisting Anxiety-like Behaviors.

    PubMed

    Kim, Tae-Kyung; Han, Pyung-Lim

    2016-08-01

    Chronic stress induces anxiety disorders, whereas physical exercise is believed to help people with clinical anxiety. In the present study, we investigated the mechanisms underlying stress-induced anxiety and its counteraction by exercise using an established animal model of anxiety. Mice treated with restraint for 2 h daily for 14 days exhibited anxiety-like behaviors, including social and nonsocial behavioral symptoms, and these behavioral impairments lasted for more than 12 weeks after the stress treatment was removed. Despite these lasting behavioral changes, wheel-running exercise treatment for 1 h daily from post-stress days 1 - 21 counteracted anxiety-like behaviors, and these anxiolytic effects of exercise persisted for more than 2 months, suggesting that anxiolytic effects of exercise stably induced. Repeated restraint treatment up-regulated the expression of the neuropeptide, melanin-concentrating hormone (MCH), in the lateral hypothalamus, hippocampus, and basolateral amygdala, the brain regions important for emotional behaviors. In an in vitro study, treatment of HT22 hippocampal cells with glucocorticoid increased MCH expression, suggesting that MCH upregulation can be initially triggered by the stress hormone, corticosterone. In contrast, post-stress treatment with wheel-running exercise reduced the stress-induced increase in MCH expression to control levels in the lateral hypothalamus, hippocampus and basolateral amygdala. Administration of an MCH receptor antagonist (SNAP94847) to stress-treated mice was therapeutic against stress-induced anxiety-like behaviors. These results suggest that repeated stress produces long-lasting anxiety-like behaviors and upregulates MCH in the brain, while exercise counteracts stress-induced MCH expression and persisting anxiety-like behaviors. PMID:27574483

  17. Physical Exercise Counteracts Stress-induced Upregulation of Melanin-concentrating Hormone in the Brain and Stress-induced Persisting Anxiety-like Behaviors

    PubMed Central

    Kim, Tae-Kyung

    2016-01-01

    Chronic stress induces anxiety disorders, whereas physical exercise is believed to help people with clinical anxiety. In the present study, we investigated the mechanisms underlying stress-induced anxiety and its counteraction by exercise using an established animal model of anxiety. Mice treated with restraint for 2 h daily for 14 days exhibited anxiety-like behaviors, including social and nonsocial behavioral symptoms, and these behavioral impairments lasted for more than 12 weeks after the stress treatment was removed. Despite these lasting behavioral changes, wheel-running exercise treatment for 1 h daily from post-stress days 1 - 21 counteracted anxiety-like behaviors, and these anxiolytic effects of exercise persisted for more than 2 months, suggesting that anxiolytic effects of exercise stably induced. Repeated restraint treatment up-regulated the expression of the neuropeptide, melanin-concentrating hormone (MCH), in the lateral hypothalamus, hippocampus, and basolateral amygdala, the brain regions important for emotional behaviors. In an in vitro study, treatment of HT22 hippocampal cells with glucocorticoid increased MCH expression, suggesting that MCH upregulation can be initially triggered by the stress hormone, corticosterone. In contrast, post-stress treatment with wheel-running exercise reduced the stress-induced increase in MCH expression to control levels in the lateral hypothalamus, hippocampus and basolateral amygdala. Administration of an MCH receptor antagonist (SNAP94847) to stress-treated mice was therapeutic against stress-induced anxiety-like behaviors. These results suggest that repeated stress produces long-lasting anxiety-like behaviors and upregulates MCH in the brain, while exercise counteracts stress-induced MCH expression and persisting anxiety-like behaviors. PMID:27574483

  18. Resistance exercise induced mTORC1 signaling is not impaired by subsequent endurance exercise in human skeletal muscle.

    PubMed

    Apró, William; Wang, Li; Pontén, Marjan; Blomstrand, Eva; Sahlin, Kent

    2013-07-01

    The current dogma is that the muscle adaptation to resistance exercise is blunted when combined with endurance exercise. The suggested mechanism (based on rodent experiments) is that activation of adenosine monophosphate-activated protein kinase (AMPK) during endurance exercise impairs muscle growth through inhibition of the mechanistic target of rapamycin complex 1 (mTORC1). The purpose of this study was to investigate potential interference of endurance training on the signaling pathway of resistance training [mTORC1 phosphorylation of ribosomal protein S6 kinase 1 (S6K1)] in human muscle. Ten healthy and moderately trained male subjects performed on two separate occasions either acute high-intensity and high-volume resistance exercise (leg press, R) or R followed by 30 min of cycling (RE). Muscle biopsies were collected before and 1 and 3 h post resistance exercise. Phosphorylation of mTOR (Ser²⁴⁴⁸) increased 2-fold (P < 0.05) and that of S6K1 (Thr³⁸⁹) 14-fold (P < 0.05), with no difference between R and RE. Phosphorylation of eukaryotic elongation factor 2 (eEF2, Thr⁵⁶) was reduced ~70% during recovery in both trials (P < 0.05). An interesting finding was that phosphorylation of AMPK (Thr¹⁷²) and acetyl-CoA carboxylase (ACC, Ser⁷⁹) decreased ~30% and ~50%, respectively, 3 h postexercise (P < 0.05). Proliferator-activated receptor-γ coactivator-1 (PGC-1α) mRNA increased more after RE (6.5-fold) than after R (4-fold) (RE vs. R: P < 0.01) and was the only gene expressed differently between trials. These data show that the signaling of muscle growth through the mTORC1-S6K1 axis after heavy resistance exercise is not inhibited by subsequent endurance exercise. It is also suggested that prior activation of mTORC1 signaling may repress subsequent phosphorylation of AMPK. PMID:23632629

  19. A single prior bout of exercise protects against palmitate-induced insulin resistance despite an increase in total ceramide content.

    PubMed

    Thrush, A Brianne; Harasim, Ewa; Chabowski, Adrian; Gulli, Roberto; Stefanyk, Leslie; Dyck, David J

    2011-05-01

    Ceramide accumulation has been implicated in the impairment of insulin-stimulated glucose transport in skeletal muscle following saturated fatty acid (FA) exposure. Importantly, a single bout of exercise can protect against acute lipid-induced insulin resistance. The mechanism by which exercise protects against lipid-induced insulin resistance is not completely known but may occur through a redirection of FA toward triacylglycerol (TAG) and away from ceramide and diacylglycerol (DAG). Therefore, in the current study, an in vitro preparation was used to examine whether a prior bout of exercise could confer protection against palmitate-induced insulin resistance and whether the pharmacological [50 μM fumonisin B(1) (FB1)] inhibition of ceramide synthesis in the presence of palmitate could mimic the protective effect of exercise. Soleus muscle of sedentary (SED), exercised (EX), and SED in the presence of FB1 (SED+FB1) were incubated with or without 2 mM palmitate for 4 h. This 2-mM palmitate exposure impaired insulin-stimulated glucose transport (-28%, P < 0.01) and significantly increased ceramide, DAG, and TAG accumulation in the SED group (P < 0.05). A single prior bout of exercise prevented the detrimental effects of palmitate on insulin signaling and caused a partial redistribution of FA toward TAG (P < 0.05). However, the net increase in ceramide content in response to palmitate exposure in the EX group was not different compared with SED, despite the maintenance of insulin sensitivity. The incubation of soleus from SED rats with FB1 (SED+FB1) prevented the detrimental effects of palmitate and caused a redirection of FA toward TAG accumulation (P < 0.05). Therefore, this research suggests that although inhibiting ceramide accumulation can prevent the detrimental effects of palmitate, a single prior bout of exercise appears to protect against palmitate-induced insulin resistance, which may be independent of changes in ceramide content. PMID:21325642

  20. Swimming exercise ameliorates neurocognitive impairment induced by neonatal exposure to isoflurane and enhances hippocampal histone acetylation in mice.

    PubMed

    Zhong, T; Ren, F; Huang, C S; Zou, W Y; Yang, Y; Pan, Y D; Sun, B; Wang, E; Guo, Q L

    2016-03-01

    Isoflurane-induced neurocognitive impairment in the developing rodent brain is well documented, and regular physical exercise has been demonstrated to be a viable intervention for some types of neurocognitive impairment. This study was designed to investigate the potential protective effect of swimming exercise on both neurocognitive impairment caused by repeated neonatal exposure to isoflurane and the underlying molecular mechanism. Mice received 0.75% isoflurane exposures for 4h on postnatal days 7, 8, and 9. From the third month after anesthesia, the mice were subjected to regular swimming exercise for 4weeks, followed by a contextual fear condition (CFC) trial. We found that repeated neonatal exposure to isoflurane reduced freezing behavior during CFC testing and deregulated hippocampal histone H4K12 acetylation. Conversely, mice subjected to regular swimming exercise showed enhanced hippocampal H3K9, H4K5, and H4K12 acetylation levels, increased numbers of c-Fos-positive cells 1h after CFC training, and less isoflurane-induced memory impairment. We also observed increases in histone acetylation and of cAMP-response element-binding protein (CREB)-binding protein (CBP) during the swimming exercise program. The results suggest that neonatal isoflurane exposure-induced memory impairment was associated with dysregulation of H4K12 acetylation, which may lead to less hippocampal activation following learning tasks. Swimming exercise was associated with enhanced hippocampal histone acetylation and CBP expression. Exercise most likely ameliorated isoflurane-induced memory impairment by enhancing hippocampal histone acetylation and activating more neuron cells during memory formation. PMID:26748054

  1. Melatonin Reduces Oxidative Stress and Cardiovascular Changes Induced by Stanozolol in Rats Exposed to Swimming Exercise

    PubMed Central

    Barbosa dos Santos, Gustavo; Machado Rodrigues, Marcelo José; Gonçalves, Estela Maria; Cintra Gomes Marcondes, Maria Cristina; Areas, Miguel Arcanjo

    2013-01-01

    Objective: Anabolic-androgenic steroids (AAS) are nominated for clinical use to promote protein synthesis in many therapeutic conditions. However, the indiscriminate use of AAS is related to hazardous cardiac disturbances and oxidative stress. We designed a study to investigate whether prolonged treatment with high doses of stanozolol modifies the activities of some antioxidant enzymes in the heart in sedentary and trained rats and whether this treatment causes alterations of cardiovascular parameters. In addition, the effectiveness of melatonin as an antioxidant and as a modulator of the cardiovascular side effects of stanozolol (STA) treatment was analyzed. Materials and Methods: Thirty male Wistar rats were divided into the following six groups: sedentary (S), stanozolol sedentary (SS), stanozolol-melatonin sedentary (SMS), trained (T), stanozolol trained (ST) and stanozolol-melatonin trained (SMT). The stanozolol-treatment rats received 5 mg.kg−1 by subcutaneous injection before each exercise session (5 d.wk−1, i.e., 25 mg.kg−1.wk−1), while control groups received only saline solution injection. The melatonin-treatment groups received intraperitoneal injections of melatonin (10 mg.kg−1), 5 d.wk−1 for 6 wk. Electrocardiography, blood pressure and antioxidant enzyme activity measurements were performed at the end of the experimental period for cardiac function and molecular assessment. Results: This is the first time that the in vivo effects of melatonin treatment on stanozolol-induced cardiovascular side effects have been studied. Stanozolol induced bradycardia and significantly increased cardiac superoxide dismutase and catalase activities. Trained stanozolol-treated rats experienced an increase in blood pressure and relative heart weight, and they developed left cardiac axis deviation. Although melatonin did not prevent cardiac hypertrophy in exercised stanozolol-treated animals, it maintained blood pressure and cardiac catalase activity, and it

  2. Exercise-induced intrapulmonary shunting of venous gas emboli does not occur after open-sea diving.

    PubMed

    Dujić, Zeljko; Palada, Ivan; Obad, Ante; Duplancić, Darko; Brubakk, Alf O; Valic, Zoran

    2005-09-01

    Paradoxical arterializations of venous gas emboli can lead to neurological damage after diving with compressed air. Recently, significant exercise-induced intrapulmonary anatomical shunts have been reported in healthy humans that result in widening of alveolar-to-arterial oxygen gradient. The aim of this study was to examine whether intrapulmonary shunts can be found following strenuous exercise after diving and, if so, whether exercise should be avoided during that period. Eleven healthy, military male divers performed an open-sea dive to 30 m breathing air, remaining at pressure for 30 min. During the bottom phase of the dive, subjects performed mild exercise at approximately 30% of their maximal oxygen uptake. The ascent rate was 9 m/min. Each diver performed graded upright cycle ergometry up to 80% of the maximal oxygen uptake 40 min after the dive. Monitoring of venous gas emboli was performed in both the right and left heart with an ultrasonic scanner every 20 min for 60 min after reaching the surface pressure during supine rest and following two coughs. The diving profile used in this study produced significant amounts of venous bubbles. No evidence of intrapulmonary shunting was found in any subject during either supine resting posture or any exercise grade. Also, short strenuous exercise after the dive did not result in delayed-onset decompression sickness in any subject, but studies with a greater number of participants are needed to confirm whether divers should be allowed to exercise after diving. PMID:15845772

  3. Exercise-induced lactate accumulation regulates intramuscular triglyceride metabolism via transforming growth factor-β1 mediated pathways.

    PubMed

    Nikooie, Rohollah; Samaneh, Sajadian

    2016-01-01

    The mechanism regulating the utilization of intramuscular triacylglycerol (IMTG) during high-intensity interval training (HIIT) and post-exercise recovery period remains elusive. In this study, the acute and long-term effects of HIIT on transforming growth factor beta 1 (TGF-β1) abundance in rat skeletal muscle and role of lactate and TGF-β1 in IMTG lipolysis during post-exercise recovery period were examined. TGF-β1 and Adipose triacylglycerol lipase (ATGL) abundance as well as total lipase activity in the gastrocnemius muscle significantly increased to a maximum value 10 h after acute bout of HIIT. Inhibition of TGF-β1 signaling by intramuscular injection of SB431542 30 min prior to the acute exercise attenuated ATGL abundance and total lipase activity in the gastrocnemius muscle in response to acute exercise. Intramuscular acute injection of lactate increased TGF-β1 and ATGL abundance in the gastrocnemius muscle and there were a significant increase in Muscle TGF-β1 and ATGL abundance after 5 weeks of HIIT/lactate treatment. These results indicate that exercise-induced lactate accumulation regulates intramuscular triglyceride metabolism via transforming growth factor-β1 mediated pathways during post-exercise recovery from strenuous exercise. PMID:26522131

  4. Exercise and the asthmatic.

    PubMed

    Bundgaard, A

    1985-01-01

    Physical exercise is not hazardous to asthmatics. Some asthmatics may benefit from physical training, and almost all asthmatics can perform any kind of physical exercise. Free running was earlier thought to induce more asthma than swimming, for example; however, when ventilation is identical during running and swimming, the exercise-induced asthma will also be the same. Hyperventilation alone is as good as physical exercise to induce exercise-induced asthma. If the physical exercise provokes an asthmatic attack, this is most often easily reversed by inhaled beta 2-agonists. Pretreatment of exercise-induced asthma is most efficient by inhaled beta 2-agonist; orally dosed beta 2-agonist is not as efficient as inhaled beta 2-agonist in the pretreatment of exercise-induced asthma. Inhaled sodium cromoglycate diminishes exercise-induced asthma, and the effect seems to be better in children than in adults. Inhaled steroids have no immediate effect on exercise-induced asthma, but long term treatment with steroids diminishes exercise-induced asthma. The pathogenesis of exercise-induced asthma remains obscure. If the water content is low in the inhaled air, e.g. in cold air, the changes in ventilatory capacity following exercise. will be greater than when the exercise is performed while inhaling hot air with high humidity. Almost all asthmatics present changes in the ventilatory capacity following exercise. Seasonal changes in exercise-induced asthma are only present in asthmatics with seasonal allergies, e.g. pollen allergy. No diurnal variation is found in exercise-induced asthma. Asthmatics can do any form of physical exercise. Almost all asthmatics can prevent major changes in ventilatory capacity by pretreatment of exercise-induced asthma or be treated for exercise-induced asthma during the physical activity so that they will not suffer from asthma while performing physical exercise. Asthmatics who have been successfully treated for exercise-induced asthma can do

  5. Physical exercise-induced expression of inducible nitric oxide synthase and heme oxygenase-1 in human leukocytes: effects of RRR-alpha-tocopherol supplementation.

    PubMed

    Niess, A M; Sommer, M; Schneider, M; Angres, C; Tschositsch, K; Golly, I C; Battenfeld, N; Northoff, H; Biesalski, H K; Dickhuth, H H; Fehrenbach, E

    2000-01-01

    This study evaluated the effects of RRR-alpha-tocopherol (500 IU/day, 8 days) on in vivo cytokine response and cytoplasmic expression of inducible nitric oxide synthase (iNOS) and the antioxidant stress protein heme oxygenase-1 (HO-1) in human leukocytes after exhaustive exercise. Thirteen men were investigated in a double-blind, placebo-controlled, cross-over study with a wash-out period of 28 days. The exercise procedure consisted of an incremental treadmill test followed by a continuous run until exhaustion at 110% of the individual anaerobic threshold (total duration 28.5 +/- 0.8 min). HO-1 and iNOS protein were assessed in mono- (M), lympho-, and granulocytes (G) using flow cytometry. Plasma interleukin-6 (IL-6) and IL-8 were measured by ELISA. IL-6 rose significantly whereas IL-8 did not exhibit significant changes after exercise. Changes of IL-6 were not affected by RRR-alpha-tocopherol. Exercise induced an increase of iNOS protein primarily in M and G. A small, but significant, increase of HO-1 protein was measured in M and G. RRR-alpha-Tocopherol did not show any significant effects on cytoplasmic expression of iNOS and HO-1 at rest and after exercise. In conclusion, exhaustive exercise induces expression of iNOS and HO-1 in human leukocytes by a mechanism that is not sensitive to RRR-alpha-tocopherol supplementation. PMID:11232592

  6. Clinical significance of exercise-induced left ventricular wall motion abnormality occurring at a low heart rate

    SciTech Connect

    Kimchi, A.; Rozanski, A.; Fletcher, C.; Maddahi, J.; Swan, H.J.; Berman, D.S.

    1987-10-01

    We studied the relationship between the heart rate at the time of onset of exercise-induced wall motion abnormality and the severity of coronary artery disease in 89 patients who underwent exercise equilibrium radionuclide ventriculography as part of their evaluation for coronary artery disease. Segmental wall motion was scored with a five-point system (3 = normal; -1 = dyskinesis); a decrease of one score defined the onset of wall motion abnormality. The onset of wall motion abnormality at less than or equal to 70% of maximal predicted heart rate had 100% predictive accuracy for coronary artery disease and higher sensitivity than the onset of ischemic ST segment depression at similar heart rate during exercise: 36% (25 of 69 patients with coronary disease) vs 19% (13 of 69 patients), p = 0.01. Wall motion abnormality occurring at less than or equal to 70% of maximal predicted heart rate was present in 49% of patients (23 of 47) with critical stenosis (greater than or equal to 90% luminal diameter narrowing), and in only 5% of patients (2 of 42) without such severe stenosis, p less than 0.001. The sensitivity of exercise-induced wall motion abnormality occurring at a low heart rate for the presence of severe coronary artery disease was similar to that of a deterioration in wall motion by more than two scores during exercise (49% vs 53%) or an absolute decrease of greater than or equal to 5% in exercise left ventricular ejection fraction (49% vs 45%).

  7. Temperature- and exercise-induced gene expression and metabolic enzyme changes in skeletal muscle of adult zebrafish (Danio rerio)

    PubMed Central

    McClelland, Grant B; Craig, Paul M; Dhekney, Kalindi; Dipardo, Shawn

    2006-01-01

    Both exercise training and cold acclimatization induce muscle remodelling in vertebrates, producing a more aerobic phenotype. In ectothermic species exercise training and cold-acclimatization represent distinct stimuli. It is currently unclear if these stimuli act through a common mechanism or if different mechanisms lead to a common phenotype. The goal of this study was to survey responses that represent potential mechanisms responsible for contraction- and temperature-induced muscle remodelling, using an ectothermic vertebrate. Separate groups of adult zebrafish (Danio rerio) were either swim trained or cold acclimatized for 4 weeks. We found that the mitochondrial marker enzyme citrate synthase (CS) was increased by 1.5× in cold and by 1.3× with exercise (P < 0.05). Cytochrome c oxidase (COx) was increased by 1.2× following exercise training (P < 0.05) and 1.2× (P = 0.07) with cold acclimatization. However, only cold acclimatization increased β-hydroxyacyl-CoA dehydrogenase (HOAD) compared to exercise-trained (by 1.3×) and pyruvate kinase (PK) relative to control zebrafish. We assessed the whole-animal performance outcomes of these treatments. Maximum absolute sustained swimming speed (Ucrit) was increased in the exercise trained group but not in the cold acclimatized group. Real-time PCR analysis indicated that increases in CS are primarily transcriptionally regulated with exercise but not with cold treatments. Both treatments showed increases in nuclear respiratory factor (NRF)-1 mRNA which was increased by 2.3× in cold-acclimatized and 4× in exercise-trained zebrafish above controls. In contrast, peroxisome proliferator-activated receptor (PPAR)-α mRNA levels were decreased in both experimental groups while PPAR-β1 declined in exercise training only. Moreover, PPAR-γ coactivator (PGC)-1α mRNA was not changed by either treatment. In zebrafish, both temperature and exercise produce a more aerobic phenotype, but there are stimulus-dependent responses

  8. Incidence of exercise-induced asthma in adolescent athletes under different training and environmental conditions.

    PubMed

    Sidiropoulou, Maria P; Kokaridas, Dimitrios G; Giagazoglou, Paraskevi F; Karadonas, Michalis I; Fotiadou, Eleni G

    2012-06-01

    The aim of this study was to establish if there were differences in the incidence of exercise-induced bronchospasm between athletes in different sports, which take place under different environmental conditions such as open places, closed courses, and swimming pools with similar exercise intensity (football, basketball, water polo) using the free running test. The study included 90 adolescents (3 groups of 30) aged 14-18 years recruited from academies in northern Greece. All the participants were initially subjected to (a) a clinical examination and cardiorespiratory assessment by a physician and (b) free running test of a 6-minute duration and measurement with a microspirometer of the forced expiratory volume in 1 second (FEV₁). Only the participants who had measured a decrease in FEV₁ ≥ 10% were reevaluated with the microspirometer during a training session. The examination of all the participants during the free running test showed that 22 athletes, that is, 9, 8, and 5 of football, basketball, and water polo athletes, respectively, demonstrated an FEV₁ ≥ 10 drop. Reevaluation of the 22 participants during training showed that 5 out 9 (55%) football athletes, 4 out of 8 basketball athletes (50%), and none of the 5 athletes of the water polo team displayed a drop of FEV₁ ≥ 10%. Despite the absence of any significant statistical differences between the 3 groups, the analysis of variances did show a trend of a lower incidence of EIA in the water polo athletes. It was found that a football or basketball game can induce EIA in young athletes but to a lesser degree than the free running test can induce. The water polo can be a safer sport even for participants with a medical history of asthma or allergies. PMID:21912293

  9. Treadmill exercise training prevents myocardial mechanical dysfunction induced by androgenic-anabolic steroid treatment in rats.

    PubMed

    Bocalini, Danilo S; Beutel, Abram; Bergamaschi, Cássia T; Tucci, Paulo J; Campos, Ruy R

    2014-01-01

    Elevated concentrations of testosterone and its synthetic analogs may induce changes in cardiovascular function. However, the effects of the combination of anabolic/androgenic steroid (AAS) treatment and exercise training on systolic and diastolic cardiac function are poorly understood. In the present study, we aimed to investigate the effects of low-dose steroid treatment (stanozolol) on cardiac contractile parameters when this steroid treatment was combined with exercise training in rats and the effects of chronic steroid treatment on the Frank-Starling (length-tension curves) relationship. Male Wistar rats were randomly assigned to one of four groups: U (untrained), US (untrained and treated with stanozolol 5 mg/kg/week), T (trained, 16 m/min/1 h) and TS (trained and treated with stanozolol 5 mg/kg/week). Continuous exercise training was conducted 5 days/week for 8 consecutive weeks. The speed of the treadmill was gradually increased to a final setting of 16 m/min/1 h. Experiments were divided into two independent series: 1) central hemodynamic analysis for mean arterial blood pressure (MAP) and cardiac output (CO) measurements and 2) isolated papillary muscle preparation in Krebs solution. Stanozolol treatment significantly increased the MAP and the heart size in untrained and trained rats (U 113±2; T 106±2; US 138±8 and TS 130±7 mmHg). Furthermore, stanozolol significantly decreased developed tension and dT/dt (maximal and minimal) in U rats. However, the developed tension was completely restored by training. The Frank/Starling relationship was impaired in rats treated with stanozolol; however, again, training completely restored diastolic function. Taken together, the present data suggest that AAS treatment is able to decrease cardiac performance (systolic and diastolic functions). The combination of stanozolol and physical training improved cardiac performance, including diastolic and systolic functions, independent of changes in central hemodynamic

  10. Preventive Effects of Forced Exercise against Alcohol-induced Physical Dependency and Reduction of Pain Perception Threshold

    PubMed Central

    Motaghinejad, Majid; Ghaleni, Majid Asadi; Motaghinejad, Ozra

    2014-01-01

    Background: Treatment of postabstinence syndrome of alcohol is one of the major strategies of alcoholism treatment. Exercise can be modulated major brain pathways such as a reward system and pain perception centers. The aim of this study was to evaluation the effects of forced exercise in the management of alcohol dependence and pain perception alteration which induced by alcoholism. Methods: 72 adult male rats were divided into 2 major groups: (1) 40 of them was divided into groups of positive control (alcohol dependent) negative control and alcohol dependent groups under treatment by forced exercise, diazepam (0.4 mg/kg) and forced exercise in combination with diazepam and alcohol withdrawal signs, and blood cortisols, were measured in this groups. (2) 32 rats were divided into control, alcohol dependent (without treatment), and alcohol-dependent groups under treatment by forced exercise or indometacin (5 mg/kg) and then pain perception was assessed by using writhing test, tail-flick and hot plate test. Results: Forced exercise, diazepam, and their combinations significantly attenuates withdrawal syndrome to 20 ± 2, 22 ± 1.3 and 16 ± 2 and blood cortisol level to 6.8 ± 1.3,7.9 ± 1.2 and 5.8 ± 1.1, respectively, in comparison with the positive control group (P < 0.05 and P < 0.001). In alcohol dependent animal under treatment by forced exercise, pain response significantly inhibited with 37%, 57% and 38% decreases in writhing test, hot plate, and tail-flick test, respectively, in comparison with alcohol dependent (without treatment) group (P < 0.05). Conclusions: This study suggested that forced exercise can be useful as adjunct therapy in alcoholism patient and also can be effective in modulation of pain threshold reduction that was induced by alcohol dependency. PMID:25400889

  11. Exercise-induced improvement in cognitive performance after traumatic brain-injury in rats is dependent on BDNF Activation

    PubMed Central

    Griesbach, Grace Sophia; Hovda, David Allen; Gomez-Pinilla, Fernando

    2009-01-01

    We have previously shown that voluntary exercise upregulates brain-derived neurotrophic factor (BDNF) within the hippocampus and is associated with an enhancement of cognitive recovery after a lateral fluid-percussion injury (FPI). In order to determine if BDNF is critical to this effect we used an immunoadhesin chimera (TrkB-IgG) that inactivates free BDNF. This BDNF inhibitor was administered to adult male rats two weeks after they had received a mild fluid percussion injury (FPI) or sham surgery. These animals were then housed with or without access to a running wheel (RW) from post-injury-day (PID) 14 to 20. On PID 21, rats were tested for spatial learning in a Morris Water Maze. Results showed that exercise counteracted the cognitive deficits associated with the injury. However this exercise-induced cognitive improvement was attenuated in the FPI-RW rats that were treated with TrkB-IgG. Molecules important for synaptic plasticity and learning were measured in a separate group of rats that were sacrificed immediately after exercise (PID 21). Western blot analyses showed that exercise increased the mature form of BDNF, synapsin I and cyclic-AMP response-element-binding protein (CREB) in the vehicle treated Sham-RW group. However, only the mature form of BDNF and CREB were increased in the vehicle treated FPI-RW group. Blocking BDNF (pre administration of TrkB-IgG) greatly reduced the molecular effects of exercise in that exercise-induced increases of BDNF, synapsin I and CREB were not observed. These studies provide evidence that BDNF has a major role in exercise's cognitive effects in traumatically injured brain. PMID:19555673

  12. Meta-Analysis of Prognostic Implications of Exercise-Induced Ventricular Premature Complexes in the General Population.

    PubMed

    Kim, Joonseok; Kwon, Minkyung; Chang, Jinsoo; Harris, David; Gerson, Myron C; Hwang, Seung-Sik; Oh, Seung-Won

    2016-09-01

    Ventricular premature complexes (VPCs) during stress testing in the general population are commonly seen in clinical practice, but their prognostic value is not well understood. A comprehensive literature search of MEDLINE, Embase, and the Cochrane Library from January 1970 to May 2015 was conducted. Observational cohort studies on general populations evaluating the association between exercise-induced VPCs and all-cause or cardiovascular mortality were included in the analysis. Nine studies comprising 62,488 participants comparing clinical outcomes of patients with and without exercise-induced VPCs were included. The overall combined relative risks (RRs) for all-cause mortality and cardiovascular mortality in patients with exercise-induced VPCs were 1.41 (95% CI 1.23 to 1.61) and 1.86 (95% CI 1.51 to 2.30), respectively. In subgroup analysis, both frequent VPCs (RR 1.35, 95% CI 1.14 to 1.60) and infrequent VPCs (RR 1.57, 95% CI 1.13 to 2.18) were associated with an adverse outcome. VPCs during recovery were associated with an increased risk of death (RR 1.55, 95% CI 1.22 to 1.96). VPCs during exercise did not achieve statistical significance (RR 1.14, 95% CI 0.96 to 1.34), but only a few studies were included in the analysis. In conclusion, our meta-analysis suggests that exercise-induced VPCs in the general population significantly increase the risk of total mortality and cardiovascular mortality. Our study calls for further studies to assess the prognostic significance of exercise-induced VPCs and the utility of efforts to reduce the VPC burden to improve the clinical outcome. PMID:27394411

  13. Comparison of Watermelon and Carbohydrate Beverage on Exercise-Induced Alterations in Systemic Inflammation, Immune Dysfunction, and Plasma Antioxidant Capacity

    PubMed Central

    Shanely, R. Andrew; Nieman, David C.; Perkins-Veazie, Penelope; Henson, Dru A.; Meaney, Mary P.; Knab, Amy M.; Cialdell-Kam, Lynn

    2016-01-01

    Consuming carbohydrate- and antioxidant-rich fruits during exercise as a means of supporting and enhancing both performance and health is of interest to endurance athletes. Watermelon (WM) contains carbohydrate, lycopene, l-citrulline, and l-arginine. WM may support exercise performance, augment antioxidant capacity, and act as a countermeasure to exercise-induced inflammation and innate immune changes. Trained cyclists (n = 20, 48 ± 2 years) participated in a randomized, placebo controlled, crossover study. Subjects completed two 75 km cycling time trials after either 2 weeks ingestion of 980 mL/day WM puree or no treatment. Subjects drank either WM puree containing 0.2 gm/kg carbohydrate or a 6% carbohydrate beverage every 15 min during the time trials. Blood samples were taken pre-study and pre-, post-, 1 h post-exercise. WM ingestion versus no treatment for 2-weeks increased plasma l-citrulline and l-arginine concentrations (p < 0.0125). Exercise performance did not differ between WM puree or carbohydrate beverage trials (p > 0.05), however, the rating of perceived exertion was greater during the WM trial (p > 0.05). WM puree versus carbohydrate beverage resulted in a similar pattern of increase in blood glucose, and greater increases in post-exercise plasma antioxidant capacity, l-citrulline, l-arginine, and total nitrate (all p < 0.05), but without differences in systemic markers of inflammation or innate immune function. Daily WM puree consumption fully supported the energy demands of exercise, and increased post-exercise blood levels of WM nutritional components (l-citrulline and l-arginine), antioxidant capacity, and total nitrate, but without an influence on post-exercise inflammation and changes in innate immune function. PMID:27556488

  14. Comparison of Watermelon and Carbohydrate Beverage on Exercise-Induced Alterations in Systemic Inflammation, Immune Dysfunction, and Plasma Antioxidant Capacity.

    PubMed

    Shanely, R Andrew; Nieman, David C; Perkins-Veazie, Penelope; Henson, Dru A; Meaney, Mary P; Knab, Amy M; Cialdell-Kam, Lynn

    2016-01-01

    Consuming carbohydrate- and antioxidant-rich fruits during exercise as a means of supporting and enhancing both performance and health is of interest to endurance athletes. Watermelon (WM) contains carbohydrate, lycopene, l-citrulline, and l-arginine. WM may support exercise performance, augment antioxidant capacity, and act as a countermeasure to exercise-induced inflammation and innate immune changes. Trained cyclists (n = 20, 48 ± 2 years) participated in a randomized, placebo controlled, crossover study. Subjects completed two 75 km cycling time trials after either 2 weeks ingestion of 980 mL/day WM puree or no treatment. Subjects drank either WM puree containing 0.2 gm/kg carbohydrate or a 6% carbohydrate beverage every 15 min during the time trials. Blood samples were taken pre-study and pre-, post-, 1 h post-exercise. WM ingestion versus no treatment for 2-weeks increased plasma l-citrulline and l-arginine concentrations (p < 0.0125). Exercise performance did not differ between WM puree or carbohydrate beverage trials (p > 0.05), however, the rating of perceived exertion was greater during the WM trial (p > 0.05). WM puree versus carbohydrate beverage resulted in a similar pattern of increase in blood glucose, and greater increases in post-exercise plasma antioxidant capacity, l-citrulline, l-arginine, and total nitrate (all p < 0.05), but without differences in systemic markers of inflammation or innate immune function. Daily WM puree consumption fully supported the energy demands of exercise, and increased post-exercise blood levels of WM nutritional components (l-citrulline and l-arginine), antioxidant capacity, and total nitrate, but without an influence on post-exercise inflammation and changes in innate immune function. PMID:27556488

  15. No protection by oral terbutaline against exercise-induced asthma in children: a dose-response study.

    PubMed

    Fuglsang, G; Hertz, B; Holm, E B

    1993-04-01

    We wanted to assess the protective effects on exercise-induced asthma as well as the clinical efficacy and safety of increasing doses of a new sustained-release formulation of terbutaline sulphate, in 17 asthmatic children aged 6-12 yrs (mean 9 yrs). Placebo, 2, 4 and 6 mg terbutaline were given b.i.d. for 14 days, in a randomized, double-blind, cross-over design. At the end of each two week period, an exercise test was performed and plasma terbutaline was measured. Compared with placebo, no significant effect was seen on asthma symptoms monitored at home, or on exercise-induced asthma. The percentage falls in FEV1 after the exercise test were 36, 35, 27 and 28%, after placebo, 4, 8 and 12 mg terbutaline.day-1, respectively. There was no correlation between plasma terbutaline and dose of terbutaline. A small but statistically significant dose-related increase in morning and evening peak expiratory flow (PEF) recordings occurred, but the incidence of side-effects also increased with the dose given. There was a trend towards more side-effects when the high doses were used, and two patients withdrew from the study because of side-effects at this dose. It is concluded that continuous treatment, even with high doses of oral terbutaline, does not offer clinically useful protection against exercise-induced asthma. PMID:8491302

  16. Influence of vitamin D mushroom powder supplementation on exercise-induced muscle damage in vitamin D insufficient high school athletes.

    PubMed

    Shanely, R Andrew; Nieman, David C; Knab, Amy M; Gillitt, Nicholas D; Meaney, Mary Pat; Jin, Fuxia; Sha, Wei; Cialdella-Kam, Lynn

    2014-01-01

    Incidence of vitamin D deficiency is increasing worldwide. The purpose of this study was to determine if supplementation with vitamin D2 from Portobello mushroom powder would enhance skeletal muscle function and attenuate exercise-induced muscle damage in low vitamin D status high school athletes. Participants were randomised to Portobello mushroom powder (600 IU/d vitamin D2) or placebo for 6 weeks. Participants then completed a 1.5-h exercise session designed to induce skeletal muscle damage. Blood samples and measures of skeletal muscle function were taken pre-supplementation, post-supplementation/pre-exercise and post-exercise. Six weeks supplementation with vitamin D2 increased serum 25(OH)D2 by 9.9-fold and decreased serum 25(OH)D3 by 28%. Changes in skeletal muscle function and circulating markers of skeletal muscle damage did not differ between groups. In conclusion, 600 IU/d vitamin D2 increased 25(OH)D2 with a concomitant decrease in 25(OD)D3, with no effect on muscular function or exercise-induced muscle damage in high school athletes. PMID:24117183

  17. Effects of oral glutamine supplementation on exercise-induced gastrointestinal permeability and tight junction protein expression.

    PubMed

    Zuhl, Micah N; Lanphere, Kathryn R; Kravitz, Len; Mermier, Christine M; Schneider, Suzanne; Dokladny, Karol; Moseley, Pope L

    2014-01-15

    The objectives of this study are threefold: 1) to assess whether 7 days of oral glutamine (GLN) supplementation reduces exercise-induced intestinal permeability; 2) whether supplementation prevents the proinflammatory response; and 3) whether these changes are associated with upregulation of the heat shock response. On separate occasions, eight human subjects participated in baseline testing and in GLN and placebo (PLA) supplementation trials, followed by a 60-min treadmill run. Intestinal permeability was higher in the PLA trial compared with baseline and GLN trials (0.0604 ± 0.047 vs. 0.0218 ± 0.008 and 0.0272 ± 0.007, respectively; P < 0.05). IκBα expression in peripheral blood mononuclear cells was higher 240 min after exercise in the GLN trial compared with the PLA trial (1.411 ± 0.523 vs. 0.9839 ± 0.343, respectively; P < 0.05). In vitro using the intestinal epithelial cell line Caco-2, we measured effects of GLN supplementation (0, 4, and 6 mM) on heat-induced (37° or 41.8°C) heat shock protein 70 (HSP70), heat shock factor-1 (HSF-1), and occludin expression. HSF-1 and HSP70 levels increased in 6 mM supplementation at 41°C compared with 0 mM at 41°C (1.785 ± 0.495 vs. 0.6681 ± 0.290, and 1.973 ± 0.325 vs. 1.133 ± 0.129, respectively; P < 0.05). Occludin levels increased after 4 mM supplementation at 41°C and 6 mM at 41°C compared with 0 mM at 41°C (1.236 ± 0.219 and 1.849 ± 0.564 vs. 0.7434 ± 0.027, respectively; P < 0.001). GLN supplementation prevented exercise-induced permeability, possibly through HSF-1 activation. PMID:24285149

  18. Neuroprotective Effects of Endurance Exercise Against High-Fat Diet-Induced Hippocampal Neuroinflammation.

    PubMed

    Kang, E-B; Koo, J-H; Jang, Y-C; Yang, C-H; Lee, Y; Cosio-Lima, L M; Cho, J-Y

    2016-05-01

    Obesity contributes to systemic inflammation, which is associated with the varied pathogenesis of neurodegenerative diseases. Growing evidence has demonstrated that endurance exercise (EE) mitigates obesity-induced brain inflammation. However, exercise-mediated anti-inflammatory mechanisms remain largely unknown. We investigated how treadmill exercise (TE) reverses obesity-induced brain inflammation, mainly focusing on toll-like receptor-4 (TLR-4)-dependent neuroinflammation in the obese rat brain after 20 weeks of a high-fat diet (HFD). TE in HFD-fed rats resulted in a significant lowering in the homeostasis model assessment of insulin resistance index, the area under the curve for glucose and abdominal visceral fat, and also improved working memory ability in a passive avoidance task relative to sedentary behaviour in HFD-fed rats, with the exception of body weight. More importantly, TE revoked the increase in HFD-induced proinflammatory cytokines (tumour necrosis factor α and interleukin-1β) and cyclooxygenase-2, which is in parallel with a reduction in TLR-4 and its downstream proteins, myeloid differentiation 88 and tumour necrosis factor receptor associated factor 6, and phosphorylation of transforming growth factor β-activated kinase 1, IkBα and nuclear factor-κB. Moreover, TE reduced an indicator of microglia activation, ionised calcium-binding adapter molecule-1, and also decreased glial fibrillary acidic protein, an indicator of gliosis formed by activated astrocytes in the cerebral cortex and the hippocampal dentate gyrus, compared to HFD-fed sedentary rats. Finally, EE up-regulated the expression of anti-apoptotic protein, Bcl-2, and suppressed the expression of pro-apoptotic protein, Bax, in the hippocampus compared to HFD-fed sedentary rats. Taken together, these data suggest that TE may exert neuroprotective effects as a result of mitigating the production of proinflammatory cytokines by inhibiting the TLR4 signalling pathways. The results of

  19. Fish oil supplementation reduces severity of exercise-induced bronchoconstriction in elite athletes.

    PubMed

    Mickleborough, Timothy D; Murray, Rachael L; Ionescu, Alina A; Lindley, Martin R

    2003-11-15

    In elite athletes, exercise-induced bronchoconstriction (EIB) may respond to dietary modification, thereby reducing the need for pharmacologic treatment. Ten elite athletes with EIB and 10 elite athletes without EIB (control subjects) participated in a randomized, double-blind crossover study. Subjects entered the study on their normal diet, and then received either fish oil capsules containing 3.2 g eicosapentaenoic acid and 2.2 g docohexaenoic acid (n-3 polyunsaturated fatty acid [PUFA] diet; n = 5) or placebo capsules containing olive oil (placebo diet; n = 5) taken daily for 3 weeks. Diet had no effect on preexercise pulmonary function in either group or on postexercise pulmonary function in control subjects. However, in subjects with EIB, the n-3 PUFA diet improved postexercise pulmonary function compared with the normal and placebo diets. FEV1 decreased by 3 +/- 2% on n-3 PUFA diet, 14.5 +/- 5% on placebo diet, and 17.3 +/- 6% on normal diet at 15 minutes postexercise. Leukotriene (LT)E4, 9alpha, 11beta-prostaglandin F2, LTB4, tumor necrosis factor-alpha, and interleukin-1beta, all significantly decreased on the n-3 PUFA diet compared with normal and placebo diets and after the exercise challenge. These data suggest that dietary fish oil supplementation has a markedly protective effect in suppressing EIB in elite athletes, and this may be attributed to their antiinflammatory properties. PMID:12904324

  20. The effect of inter-set rest intervals on resistance exercise-induced muscle hypertrophy.

    PubMed

    Henselmans, Menno; Schoenfeld, Brad J

    2014-12-01

    Due to a scarcity of longitudinal trials directly measuring changes in muscle girth, previous recommendations for inter-set rest intervals in resistance training programs designed to stimulate muscular hypertrophy were primarily based on the post-exercise endocrinological response and other mechanisms theoretically related to muscle growth. New research regarding the effects of inter-set rest interval manipulation on resistance training-induced muscular hypertrophy is reviewed here to evaluate current practices and provide directions for future research. Of the studies measuring long-term muscle hypertrophy in groups employing different rest intervals, none have found superior muscle growth in the shorter compared with the longer rest interval group and one study has found the opposite. Rest intervals less than 1 minute can result in acute increases in serum growth hormone levels and these rest intervals also decrease the serum testosterone to cortisol ratio. Long-term adaptations may abate the post-exercise endocrinological response and the relationship between the transient change in hormonal production and chronic muscular hypertrophy is highly contentious and appears to be weak. The relationship between the rest interval-mediated effect on immune system response, muscle damage, metabolic stress, or energy production capacity and muscle hypertrophy is still ambiguous and largely theoretical. In conclusion, the literature does not support the hypothesis that training for muscle hypertrophy requires shorter rest intervals than training for strength development or that predetermined rest intervals are preferable to auto-regulated rest periods in this regard. PMID:25047853

  1. Probiotic cheese attenuates exercise-induced immune suppression in Wistar rats.

    PubMed

    Lollo, P C B; Cruz, A G; Morato, P N; Moura, C S; Carvalho-Silva, L B; Oliveira, C A F; Faria, J A F; Amaya-Farfan, J

    2012-07-01

    Intense physical activity results in a substantial volume of stress and hence a significant probability of immunosuppression in athletes, with milk proteins being, perhaps, the most recommended protein supplements. Consumption of a probiotic cheese can attenuate immune suppression induced by exhausting exercise in rats. A popular Brazilian fresh cheese (Minas Frescal cheese) containing Lactobacillus acidophilus LA14 and Bifidobacterium longum BL05 was fed for 2wk to adult Wistar rats, which then were brought to exhaustion on the treadmill. Two hours after exhaustion, the rats were killed and material was collected for the determination of serum uric acid, total and high-density lipoprotein cholesterol fraction, total protein, triacylglycerols, aspartate aminotransferase, alanine aminotransferase, creatine kinase, and blood cell (monocyte, lymphocyte, neutrophil, and leukocyte) counts. Exercise was efficient in reducing lymphocyte counts, irrespective of the type of ingested cheese, but the decrease in the group fed the probiotic cheese was 22% compared with 48% in the animals fed regular cheese. Monocyte counts were unaltered in the rats fed probiotic cheese compared with a significant decrease in the rats fed the regular cheese. Most importantly, ingestion of the probiotic cheese resulted in a >100% increase in serum high-density lipoprotein cholesterol and a 50% decrease in triacylglycerols. We conclude that probiotic Minas Frescal cheese may be a viable alternative to enhance the immune system and could be used to prevent infections, particularly those related to the physical overexertion of athletes. PMID:22720913

  2. Stretch-induced enhancement of mechanical power output in human multijoint exercise with countermovement.

    PubMed

    Takarada, Y; Hirano, Y; Ishige, Y; Ishii, N

    1997-11-01

    The relation between the eccentric force developed during a countermovement and the mechanical power output was studied in squatting exercises under nominally isotonic load (50% of 1-repetition maximum). The subjects (n = 5) performed squatting exercises with a countermovement at varied deceleration rates before lifting the load. The ground reaction force and video images were recorded to obtain the power output of the body. Net muscle moments acting at hip, knee, and ankle joints were calculated from video recordings by using inverse dynamics. When an intense deceleration was taken at the end of downward movement, large eccentric force was developed, and the mechanical power subsequently produced during the lifting movement was consistently larger than that produced without the countermovement. Both maximal and mean power outputs during concentric actions increased initially with the eccentric force, whereas they began to decline when the eccentric force exceeded approximately 1.4 times the sum of load and body weight. Video-image analysis showed that this characteristic relation was predominantly determined by the torque around the knee joint. Electromyographic analyses showed no consistent increase in time-averaged integrated electromyograph from vastus lateralis with the power output, suggesting that the enhancement of power output is primarily caused by the prestretch-induced improvement of an intrinsic force-generating capability of the agonist muscle. PMID:9375347

  3. Eucapnic Voluntary Hyperpnea: Gold Standard for Diagnosing Exercise-Induced Bronchoconstriction in Athletes?

    PubMed

    Hull, James H; Ansley, Les; Price, Oliver J; Dickinson, John W; Bonini, Matteo

    2016-08-01

    In athletes, a secure diagnos is of exercise-induced bronchoconstriction (EIB) is dependent on objective testing. Evaluating spirometric indices of airflow before and following an exercise bout is intuitively the optimal means for the diagnosis; however, this approach is recognized as having several key limitations. Accordingly, alternative indirect bronchoprovocation tests have been recommended as surrogate means for obtaining a diagnosis of EIB. Of these tests, it is often argued that the eucapnic voluntary hyperpnea (EVH) challenge represents the 'gold standard'. This article provides a state-of-the-art review of EVH, including an overview of the test methodology and its interpretation. We also address the performance of EVH against the other functional and clinical approaches commonly adopted for the diagnosis of EIB. The published evidence supports a key role for EVH in the diagnostic algorithm for EIB testing in athletes. However, its wide sensitivity and specificity and poor repeatability preclude EVH from being termed a 'gold standard' test for EIB. PMID:27007599

  4. Improving screening and diagnosis of exercise-induced bronchoconstriction: a call to action.

    PubMed

    Weiler, John M; Hallstrand, Teal S; Parsons, Jonathan P; Randolph, Christopher; Silvers, William S; Storms, William W; Bronstone, Amy

    2014-01-01

    This article summarizes the findings of an expert panel of nationally recognized allergists and pulmonologists who met to discuss how to improve detection and diagnosis of exercise-induced bronchoconstriction (EIB), a transient airway narrowing that occurs during and most often after exercise in people with and without underlying asthma. EIB is both commonly underdiagnosed and overdiagnosed. EIB underdiagnosis may result in habitual avoidance of sports and physical activity, chronic deconditioning, weight gain, poor asthma control, low self-esteem, and reduced quality of life. Routine use of a reliable and valid self-administered EIB screening questionnaire by professionals best positioned to screen large numbers of people could substantially improve the detection of EIB. The authors conducted a systematic review of the literature that evaluated the accuracy of EIB screening questionnaires that might be adopted for widespread EIB screening in the general population. Results of this review indicated that no existing EIB screening questionnaire had adequate sensitivity and specificity for this purpose. The authors present a call to action to develop a new EIB screening questionnaire, and discuss the rigorous qualitative and quantitative research necessary to develop and validate such an instrument, including key methodological pitfalls that must be avoided. PMID:24811017

  5. Genetic Ablation of CD38 Protects against Western Diet-Induced Exercise Intolerance and Metabolic Inflexibility

    PubMed Central

    Chiang, Shian-Huey; Harrington, W. Wallace; Luo, Guizhen; Milliken, Naphtali O.; Ulrich, John C.; Chen, Jing; Rajpal, Deepak K.; Qian, Ying; Carpenter, Tiffany; Murray, Rusty; Geske, Robert S.; Stimpson, Stephen A.; Kramer, Henning F.; Haffner, Curt D.; Becherer, J. David; Preugschat, Frank; Billin, Andrew N.

    2015-01-