1
|
Hu M, Han M, Zhang H, Li Z, Xu K, Kang H, Zong J, Zhao F, Liu Y, Liu W. Curcumin (CUMINUP60®) mitigates exercise fatigue through regulating PI3K/Akt/AMPK/mTOR pathway in mice. Aging (Albany NY) 2023; 15:2308-2320. [PMID: 36988546 PMCID: PMC10085593 DOI: 10.18632/aging.204614] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 03/17/2023] [Indexed: 03/30/2023]
Abstract
Curcumin is a chemical constituent extracted from Curcuma longa L. Several clinical and preclinical studies have demonstrated that it can mitigate exercise fatigue, but the exact mechanism is still unknown. Therefore, we applied a mouse model of exercise fatigue to investigate the possible molecular mechanisms of curcumin's anti-fatigue effect. Depending on body mass, Kunming mice were randomly divided into control, caffeine (positive drug), and curcumin groups, and were given 28 days intragastric administration. Both the caffeine group and curcumin group showed significant improvement in exercise fatigue compared to the control group, as evidenced by the increase in time to exhaustion, as well as the higher quadriceps coefficient, muscle glycogen (MG) content, and increase in the expression of Akt, AMPK, PI3K, and mTOR proteins. While the curcumin group also significantly improved the exercise fatigue of the mice, demonstrating a lower AMP/ATP ratio and lactic acid (LA) content, and increased glycogen synthase (GS), and myonectin content compared to the caffeine group. Therefore, in the present study, we found that curcumin can exert a similar anti-fatigue effect to caffeine and may act by regulating energy metabolism through modulating the expression of the proteins in the PI3K/Akt/AMPK/mTOR pathway.
Collapse
Affiliation(s)
- Minghui Hu
- Experimental Center, Shandong University of Traditional Chinese Medicine, Ji’nan, China
- Key Laboratory of Traditional Chinese Medicine Classical Theory, Ministry of Education, Shandong University of Traditional Chinese Medicine, Ji’nan, China
| | - Muxuan Han
- College of Health Sciences, Shandong University of Traditional Chinese Medicine, Ji’nan, China
| | - Hao Zhang
- Experimental Center, Shandong University of Traditional Chinese Medicine, Ji’nan, China
- Key Laboratory of Traditional Chinese Medicine Classical Theory, Ministry of Education, Shandong University of Traditional Chinese Medicine, Ji’nan, China
| | - Zifa Li
- Experimental Center, Shandong University of Traditional Chinese Medicine, Ji’nan, China
| | - Kaiyong Xu
- Experimental Center, Shandong University of Traditional Chinese Medicine, Ji’nan, China
| | - Huaixing Kang
- Experimental Center, Shandong University of Traditional Chinese Medicine, Ji’nan, China
| | | | - Feng Zhao
- Experimental Center, Shandong University of Traditional Chinese Medicine, Ji’nan, China
- Key Laboratory of Traditional Chinese Medicine Classical Theory, Ministry of Education, Shandong University of Traditional Chinese Medicine, Ji’nan, China
| | - Yuanxiang Liu
- The First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Ji’nan, China
| | - Wei Liu
- Department of Encephalopathy, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Ji’nan, China
| |
Collapse
|
2
|
Sogard AS, Mickleborough TD. The therapeutic potential of exercise and caffeine on attention-deficit/hyperactivity disorder in athletes. Front Neurosci 2022; 16:978336. [PMID: 36033633 PMCID: PMC9412016 DOI: 10.3389/fnins.2022.978336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is characterized by evident and persistent inattention, hyperactivity, impulsivity, and social difficulties and is the most common childhood neuropsychiatric disorder, and which may persist into adulthood. Seventy to 80% of children and adults with ADHD are treated with stimulant medication, with positive response rates occurring for both populations. Medicated ADHD individuals generally show sustained and improved attention, inhibition control, cognitive flexibility, on-task behavior, and cognitive performance. The ethics of ADHD medication use in athletics has been a debated topic in sport performance for a long time. Stimulants are banned from competition in accordance with World Anti-Doping Association and National Collegiate Athletic Association regulations, due to their ability to not only enhance cognitive performance but also exercise performance. Limited research has been conducted looking at the differences in exercise performance variables in unmedicated ADHD verses medicated ADHD. Not all ADHD athletes choose stimulant medication in their treatment plan due to personal, financial, or other reasons. Non-stimulant treatment options include non-stimulant medication and behavioral therapy. However, the use of caffeinated compounds and exercise has both independently been shown to be effective in the management of ADHD symptoms in human studies and animal models. This mini review will discuss the effect of exercise and caffeine on neurobehavioral, cognitive, and neurophysiological factors, and exercise performance in ADHD athletes, and whether exercise and caffeine should be considered in the treatment plan for an individual with ADHD.
Collapse
|
3
|
Salatino A, Iacono C, Gammeri R, Chiadò ST, Lambert J, Sulcova D, Mouraux A, George MS, Roberts DR, Berti A, Ricci R. Zero gravity induced by parabolic flight enhances automatic capture and weakens voluntary maintenance of visuospatial attention. NPJ Microgravity 2021; 7:29. [PMID: 34315902 PMCID: PMC8316350 DOI: 10.1038/s41526-021-00159-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 06/28/2021] [Indexed: 11/30/2022] Open
Abstract
Orienting attention in the space around us is a fundamental prerequisite for willed actions. On Earth, at 1 g, orienting attention requires the integration of vestibular signals and vision, although the specific vestibular contribution to voluntary and automatic components of visuospatial attention remains largely unknown. Here, we show that unweighting of the otolith organ in zero gravity during parabolic flight, selectively enhances stimulus-driven capture of automatic visuospatial attention, while weakening voluntary maintenance of covert attention. These findings, besides advancing our comprehension of the basic influence of the vestibular function on voluntary and automatic components of visuospatial attention, may have operational implications for the identification of effective countermeasures to be applied in forthcoming human deep space exploration and habitation, and on Earth, for patients’ rehabilitation.
Collapse
Affiliation(s)
- Adriana Salatino
- Department of Psychology, University of Turin, Turin, Italy. .,Institute of Neuroscience (IoN), Université Catholique de Louvain Brussels, Brussels, Belgium.
| | - Claudio Iacono
- Department of Psychology, University of Turin, Turin, Italy
| | | | | | - Julien Lambert
- Institute of Neuroscience (IoN), Université Catholique de Louvain Brussels, Brussels, Belgium
| | - Dominika Sulcova
- Institute of Neuroscience (IoN), Université Catholique de Louvain Brussels, Brussels, Belgium
| | - André Mouraux
- Institute of Neuroscience (IoN), Université Catholique de Louvain Brussels, Brussels, Belgium
| | - Mark S George
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA.,Ralph H. Johnson VA Medical Center, Charleston, SC, USA
| | - Donna R Roberts
- Department of of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Anna Berti
- Department of Psychology, University of Turin, Turin, Italy
| | - Raffaella Ricci
- Department of Psychology, University of Turin, Turin, Italy. .,Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA.
| |
Collapse
|
4
|
Ashton JS, Roberts JW, Wakefield CJ, Page RM, MacLaren DP, Marwood S, Malone JJ. The effects of medium chain triglyceride (MCT) supplementation using a C8:C10 ratio of 30:70 on cognitive performance in healthy young adults. Physiol Behav 2021; 229:113252. [DOI: 10.1016/j.physbeh.2020.113252] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/10/2020] [Accepted: 11/16/2020] [Indexed: 11/26/2022]
|
5
|
Guest NS, VanDusseldorp TA, Nelson MT, Grgic J, Schoenfeld BJ, Jenkins NDM, Arent SM, Antonio J, Stout JR, Trexler ET, Smith-Ryan AE, Goldstein ER, Kalman DS, Campbell BI. International society of sports nutrition position stand: caffeine and exercise performance. J Int Soc Sports Nutr 2021; 18:1. [PMID: 33388079 PMCID: PMC7777221 DOI: 10.1186/s12970-020-00383-4] [Citation(s) in RCA: 177] [Impact Index Per Article: 59.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 10/31/2020] [Indexed: 12/13/2022] Open
Abstract
Following critical evaluation of the available literature to date, The International Society of Sports Nutrition (ISSN) position regarding caffeine intake is as follows: 1. Supplementation with caffeine has been shown to acutely enhance various aspects of exercise performance in many but not all studies. Small to moderate benefits of caffeine use include, but are not limited to: muscular endurance, movement velocity and muscular strength, sprinting, jumping, and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions. 2. Aerobic endurance appears to be the form of exercise with the most consistent moderate-to-large benefits from caffeine use, although the magnitude of its effects differs between individuals. 3. Caffeine has consistently been shown to improve exercise performance when consumed in doses of 3-6 mg/kg body mass. Minimal effective doses of caffeine currently remain unclear but they may be as low as 2 mg/kg body mass. Very high doses of caffeine (e.g. 9 mg/kg) are associated with a high incidence of side-effects and do not seem to be required to elicit an ergogenic effect. 4. The most commonly used timing of caffeine supplementation is 60 min pre-exercise. Optimal timing of caffeine ingestion likely depends on the source of caffeine. For example, as compared to caffeine capsules, caffeine chewing gums may require a shorter waiting time from consumption to the start of the exercise session. 5. Caffeine appears to improve physical performance in both trained and untrained individuals. 6. Inter-individual differences in sport and exercise performance as well as adverse effects on sleep or feelings of anxiety following caffeine ingestion may be attributed to genetic variation associated with caffeine metabolism, and physical and psychological response. Other factors such as habitual caffeine intake also may play a role in between-individual response variation. 7. Caffeine has been shown to be ergogenic for cognitive function, including attention and vigilance, in most individuals. 8. Caffeine may improve cognitive and physical performance in some individuals under conditions of sleep deprivation. 9. The use of caffeine in conjunction with endurance exercise in the heat and at altitude is well supported when dosages range from 3 to 6 mg/kg and 4-6 mg/kg, respectively. 10. Alternative sources of caffeine such as caffeinated chewing gum, mouth rinses, energy gels and chews have been shown to improve performance, primarily in aerobic exercise. 11. Energy drinks and pre-workout supplements containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance.
Collapse
Affiliation(s)
- Nanci S Guest
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 1 King's College Circle, Room 5326A, Toronto, ON, M5S 1A8, Canada.
| | - Trisha A VanDusseldorp
- Department of Exercise Science and Sport Management, Kennesaw State University, Kennesaw, GA, 30144, USA
| | | | - Jozo Grgic
- Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia
| | - Brad J Schoenfeld
- Department of Health Sciences, CUNY Lehman College, Bronx, NY, 10468, USA
| | - Nathaniel D M Jenkins
- Department of Health and Human Physiology, University of Iowa, Iowa City, IA, 52240, USA
| | - Shawn M Arent
- Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Colombia, SC, 29208, USA
- School of Social and Health Sciences, Leeds Trinity University, Leeds, UK
| | - Jose Antonio
- Exercise and Sport Science, Nova Southeastern University, Davie, FL, 33314, USA
| | - Jeffrey R Stout
- Institue of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL, 32816, USA
| | | | - Abbie E Smith-Ryan
- Department of Exercise and Sport Science, Applied Physiology Laboratory, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Erica R Goldstein
- Institue of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL, 32816, USA
| | - Douglas S Kalman
- Nutrion Department, College of Osteopathic Medicine, Nova Southeastern University, Fort Lauderdale, FL, 33314, USA
- Scientific Affairs. Nutrasource, Guelph, ON, Canada
| | - Bill I Campbell
- Performance & Physique Enhancement Laboratory, University of South Florida, Tampa, FL, 33612, USA
| |
Collapse
|
6
|
A Multimodal Analysis Combining Behavioral Experiments and Survey-Based Methods to Assess the Cognitive Effect of Video Game Playing: Good or Evil? SENSORS 2020; 20:s20113219. [PMID: 32517096 PMCID: PMC7308934 DOI: 10.3390/s20113219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 06/01/2020] [Accepted: 06/03/2020] [Indexed: 11/16/2022]
Abstract
This study aims to bridge the gap between the discrepant views of existing studies in different modalities on the cognitive effect of video game play. To this end, we conducted a set of tests with different modalities within each participant: (1) Self-Reports Analyses (SRA) consisting of five popular self-report surveys, and (2) a standard Behavioral Experiment (BE) using pro- and antisaccade paradigms, and analyzed how their results vary between Video Game Player (VGP) and Non-Video Game Player (NVGP) participant groups. Our result showed that (1) VGP scored significantly lower in Behavioral Inhibition System (BIS) than NVGP (p = 0.023), and (2) VGP showed significantly higher antisaccade error rate than NVGP (p = 0.005), suggesting that results of both SRA and BE support the existing view that video game play has a maleficent impact on the cognition by increasing impulsivity. However, the following correlation analysis on the results across individual participants found no significant correlation between SRA and BE, indicating a complex nature of the cognitive effect of video game play.
Collapse
|
7
|
Sanchis C, Blasco E, Luna FG, Lupiáñez J. Effects of caffeine intake and exercise intensity on executive and arousal vigilance. Sci Rep 2020; 10:8393. [PMID: 32439849 PMCID: PMC7242431 DOI: 10.1038/s41598-020-65197-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 04/17/2020] [Indexed: 12/13/2022] Open
Abstract
During physical efforts and sport practice, vigilance is responsible for maintaining an optimal state of activation, guaranteeing the ability to quickly respond and detect unexpected, but critical, stimuli over time. Caffeine and physical exercise are able to modulate the activation state, affecting vigilance performance. The aim of the present work was to assess the specific effects and modulations of caffeine intake and two physical intensities on vigilance components. Participants performed an attentional task (ANTI-Vea) to measure the executive and arousal components of vigilance, in six double-blinded counterbalanced sessions combining caffeine, placebo, or no-ingestion, with light vs. moderate cyclergometer exercise. Exercise at moderate intensity improved executive vigilance with faster overall reaction time (RT), without impairing error rates. Instead, caffeine intake generally improved arousal vigilance. In conclusion, caffeine and acute exercise seems to moderate executive and arousal vigilance in different ways.
Collapse
Affiliation(s)
- Carlos Sanchis
- Faculty of Physical Education & Sport Sciences, Catholic University of Valencia, Valencia, 46001, Spain.
| | - Esther Blasco
- Faculty of Physical Education & Sport Sciences, Catholic University of Valencia, Valencia, 46001, Spain
| | - Fernando G Luna
- Department of Experimental Psychology, Mind, Brain and Behavior Research Center, University of Granada, 18071, Granada, Spain
- Instituto de Investigaciones Psicológicas (IIPsi, CONICET-UNC), Facultad de Psicología, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Juan Lupiáñez
- Department of Experimental Psychology, Mind, Brain and Behavior Research Center, University of Granada, 18071, Granada, Spain.
| |
Collapse
|
8
|
Caffeine intake modulates the functioning of the attentional networks depending on consumption habits and acute exercise demands. Sci Rep 2019; 9:10043. [PMID: 31296908 PMCID: PMC6624295 DOI: 10.1038/s41598-019-46524-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 06/28/2019] [Indexed: 01/07/2023] Open
Abstract
Consume of stimulants (as caffeine) is very usual in different contexts where the performers have to take quick and accurate decisions during physical effort. Decision-making processes are mediated by the attentional networks. An experiment was carried out to examine the effect of caffeine intake on attention (alerting, orienting, and executive control) as a function of consumption habit under two physical exertion conditions (rest vs. aerobic exercise). Two groups of participants with different caffeine consumption profiles (moderate consumers vs. low consumers) performed the Attention Network Test-Interactions under four different conditions regarding activity (rest vs. exercise) and intake (caffeine vs. placebo). Results showed that whereas exercise led to faster reaction times (RT) in all cases, caffeine intake accelerated RT but only at rest and in moderate caffeine consumers. More importantly, caffeine intake reduced the alertness effect in moderate consumers only at the rest condition. No interactions between Intake and Activity were observed in the other attentional networks, with exercise reducing orienting independently of caffeine intake, which suggests that physical exercise and caffeine are different modulators of attention but can interact. Caffeine intake had differential effects on reaction speed at rest and during physical exercise depending on the individual consumption habit. On the basis of these finding it seems that mainly alertness is modulated differently by internal and external "arousing" conditions.
Collapse
|
9
|
The quiet eye is sensitive to exercise-induced physiological stress. PROGRESS IN BRAIN RESEARCH 2018; 240:35-52. [PMID: 30390839 DOI: 10.1016/bs.pbr.2018.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The current study sought to explore attentional mechanisms underpinning visuomotor performance degradation following acute exercise. Ten experienced basketball players took free throws while wearing mobile eye tracking glasses, before and after performing a bout of cycling exercise. Shooting accuracy was measured using a 6-point scoring system, and quiet eye duration (the final fixation to a target) was adopted as an objective measure of top-down attentional control. Four intensities of exercise (based on an initial ramp test) were performed in a counterbalanced order: rest, moderate, heavy and severe. The four intensities resulted in participants reaching 52±4%, 58±4%, 76±6% and 86±5% of their heart rate max, respectively. Performance and quiet eye were only significantly impaired (19% and 45% drops, respectively) between pre- and post-intervention at the severe intensity workload level. Additionally, exercise-induced changes in quiet eye predicted 33% of the subsequent change in performance accuracy. The results suggest that attentional disruptions may at least partially explain why sporting skills break down under acute fatigue. Implications for training to mitigate against these impairments are discussed.
Collapse
|
10
|
Ma J, Chen H, Liu X, Zhang L, Qiao D. Exercise-Induced Fatigue Impairs Bidirectional Corticostriatal Synaptic Plasticity. Front Cell Neurosci 2018; 12:14. [PMID: 29422839 PMCID: PMC5788965 DOI: 10.3389/fncel.2018.00014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Accepted: 01/10/2018] [Indexed: 11/18/2022] Open
Abstract
Exercise-induced fatigue (EF) is a ubiquitous phenomenon in sports competition and training. It can impair athletes’ motor skill execution and cognition. Corticostriatal synaptic plasticity is considered to be the cellular mechanism of movement control and motor learning. However, the effect of EF on corticostriatal synaptic plasticity remains elusive. In the present study, using field excitatory postsynaptic potential recording, we found that the corticostriatal long-term potentiation (LTP) and long-term depression (LTD) were both impaired in EF mice. To further investigate the cellular mechanisms underlying the impaired synaptic plasticity in corticostriatal pathway, whole-cell patch clamp recordings were carried out on striatal medium spiny neurons (MSNs). MSNs in EF mice exhibited increased spontaneous excitatory postsynaptic current (sEPSC) frequency and decreased paired-pulse ratio (PPR), while with normal basic electrophysiological properties and normal sEPSC amplitude. Furthermore, the N-methyl-D-aspartate (NMDA)/α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) ratio of MSNs was reduced in EF mice. These results suggest that the enhanced presynaptic glutamate (Glu) release and downregulated postsynaptic NMDA receptor function lead to the impaired corticostriatal plasticity in EF mice. Taken together, our findings for the first time show that the bidirectional corticostriatal synaptic plasticity is impaired after EF, and suggest that the aberrant corticostriatal synaptic plasticity may be involved in the production and/or maintenance of EF.
Collapse
Affiliation(s)
- Jing Ma
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| | - Huimin Chen
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| | - Xiaoli Liu
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| | - Lingtao Zhang
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| | - Decai Qiao
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| |
Collapse
|
11
|
Connell CJW, Thompson B, Turuwhenua J, Srzich A, Gant N. Effects of Dopamine and Norepinephrine on Exercise-induced Oculomotor Fatigue. Med Sci Sports Exerc 2018; 49:1778-1788. [PMID: 28452866 DOI: 10.1249/mss.0000000000001307] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Fatigue-induced impairments in the control of eye movements are detectable via reduced eye movement velocity after a bout of prolonged, strenuous exercise. Slower eye movements caused by neural fatigue within the oculomotor system can be prevented by caffeine, and the upregulation of central catecholamines may be responsible for this effect. This study explored the individual contribution of dopamine and norepinephrine to fatigue-related impairments in oculomotor control. METHODS The influence of a dopamine reuptake inhibitor (methylphenidate) and a norepinephrine reuptake inhibitor (reboxetine) was assessed in 12 cyclists performing 180 min of stationary cycling within a placebo-controlled crossover design. Eye movement kinematics (saccades, smooth pursuit, and optokinetic nystagmus) were measured using infrared oculography. Visual attention was assessed with overt and covert spatial attention tasks. RESULTS Exercise-induced fatigue was associated with a 6% ± 8% reduction in the peak velocity of visually guided, reflexive prosaccades. Importantly, both dopamine reuptake inhibition and norepinephrine reuptake inhibition prevented fatigue-related decrements in the peak velocity of prosaccades. Pursuit eye movements, optokinetic nystagmus, and visual attention tasks were unaffected by exercise or drug treatments. CONCLUSION Overall, our findings suggest that alterations in norepinephrinergic and dopaminergic neurotransmission are linked with the development of fatigue within circuits that control eye movements. Psychiatric medications that target central catecholamines can exert a protective effect on eye movements after prolonged exercise.
Collapse
Affiliation(s)
- Charlotte J W Connell
- 1Department of Exercise Sciences, Centre for Brain Research, University of Auckland, Auckland, NEW ZEALAND; 2School of Optometry and Vision Science, University of Waterloo, Ontario, CANADA; and 3Department of Optometry and Vision Science, University of Auckland, Auckland, NEW ZEALAND
| | | | | | | | | |
Collapse
|
12
|
Caffeine increases the velocity of rapid eye movements in unfatigued humans. Psychopharmacology (Berl) 2017; 234:2311-2323. [PMID: 28536868 DOI: 10.1007/s00213-017-4638-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 05/02/2017] [Indexed: 12/25/2022]
Abstract
BACKGROUND Caffeine is a widely used dietary stimulant that can reverse the effects of fatigue on cognitive, motor and oculomotor function. However, few studies have examined the effect of caffeine on the oculomotor system when homeostasis has not been disrupted by physical fatigue. This study examined the influence of a moderate dose of caffeine on oculomotor control and visual perception in participants who were not fatigued. METHODS Within a placebo-controlled crossover design, 13 healthy adults ingested caffeine (5 mg·kg-1 body mass) and were tested over 3 h. Eye movements, including saccades, smooth pursuit and optokinetic nystagmus, were measured using infrared oculography. RESULTS Caffeine was associated with higher peak saccade velocities (472 ± 60° s-1) compared to placebo (455 ± 62° s-1). Quick phases of optokinetic nystagmus were also significantly faster with caffeine, whereas pursuit eye movements were unchanged. Non-oculomotor perceptual tasks (global motion and global orientation processing) were unaffected by caffeine. CONCLUSIONS These results show that oculomotor control is modulated by a moderate dose of caffeine in unfatigued humans. These effects are detectable in the kinematics of rapid eye movements, whereas pursuit eye movements and visual perception are unaffected. Oculomotor functions may be sensitive to changes in central catecholamines mediated via caffeine's action as an adenosine antagonist, even when participants are not fatigued.
Collapse
|
13
|
Fatigue-related impairments in oculomotor control are prevented by norepinephrine-dopamine reuptake inhibition. Sci Rep 2017; 7:42726. [PMID: 28198465 PMCID: PMC5309883 DOI: 10.1038/srep42726] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 01/12/2017] [Indexed: 11/09/2022] Open
Abstract
Fatigue-induced reductions in saccade velocity have been reported following acute, prolonged exercise. Interestingly, the detrimental impact of fatigue on oculomotor control can be prevented by a moderate dose of caffeine. This effect may be related to central catecholamine upregulation via caffeine's action as an adenosine antagonist. To test this hypothesis, we compared the protective effect of caffeine on oculomotor control post-exercise to that of a norepinephrine-dopamine reuptake inhibitor. Within a placebo-controlled crossover design, 12 cyclists consumed placebo, caffeine or a norepinephrine-dopamine reuptake inhibitor (bupropion) during 180 minutes of stationary cycling. Saccades, smooth pursuit and optokinetic nystagmus were measured using infrared oculography. Exercise fatigue was associated with an 8 ± 11% reduction in the peak velocity of prosaccades, and a 10 ± 11% decrement in antisaccade peak velocity. Optokinetic nystagmus quick phases decreased in velocity by 15 ± 17%. These differences were statistically significant (p < 0.05). Norepinephrine-dopamine reuptake inhibition and caffeine prevented fatigue-related decrements in eye movement velocity. Pursuit eye movements and visual attention were unaffected. These findings show that norepinephrine-dopamine reuptake inhibition protects oculomotor function during exercise fatigue. Caffeine's fatigue-reversing effects on eye movements appear to be mediated, at least in part, via modulation of central catecholamines.
Collapse
|