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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 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

  17. 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

  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 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

  16. 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

  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

    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

  4. 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

  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 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

  8. 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

  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. 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

  11. 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.

  12. 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

  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. 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

  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. 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

  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. 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

  8. 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

  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. 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

  17. 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

  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. 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

  1. 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

  2. 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

  3. 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

  4. 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

  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. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  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. 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

  9. 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

  10. 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

  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. 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

  15. 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

  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. 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.

  18. 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

  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. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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.

  15. 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.

  16. 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

  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. 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

  19. 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

  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. 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

  2. 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

  3. 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

  4. 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

  5. [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

  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. 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.

  15. 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

  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. 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

  19. 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

  20. 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

  1. 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 ...

  2. 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

  3. 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

  4. 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...

  5. 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

  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. 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