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1.
Nutrients ; 16(11)2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38892701

ABSTRACT

This systematic review aimed to evaluate the effectiveness of the independent or combined use of nutritional ergogenic aids belonging to Group A of the ABCD classification by the Australian Institute of Sport (AIS) in the context of cycling (caffeine, creatine, sodium bicarbonate, beta-alanine, nitrates, and glycerol). A comprehensive search was carried out using three databases: PubMed, Scopus, and Web of Science. All the databases were searched for Randomized Controlled Trials or crossover design studies assessing the effects of supplementation on cycling performance in comparison with placebos in healthy adults. The methodological quality of each study was evaluated using the Physiotherapy Evidence Database scale. Thirty-six articles involving 701 participants were included in this review, examining supplementation with caffeine (n = 5), creatine (n = 2), sodium bicarbonate (n = 6), beta-alanine (n = 3), and nitrates (n = 8). Additionally, supplemental combinations of caffeine and creatine (n = 3), caffeine and sodium bicarbonate (n = 3), caffeine and nitrates (n = 1), creatine and sodium bicarbonate (n = 1), and sodium bicarbonate and beta-alanine (n = 4) were analyzed. A benefit for cyclists' athletic performnce was found when consuming a caffeine supplement, and a potential positive effect was noted after the consumption of sodium bicarbonate, as well as after the combination of caffeine and creatine. However, no statistically significant effects were identified for the remaining supplements, whether administered individually or in combination.


Subject(s)
Athletic Performance , Bicycling , Caffeine , Creatine , Dietary Supplements , Nitrates , Performance-Enhancing Substances , Humans , Bicycling/physiology , Athletic Performance/physiology , Nitrates/administration & dosage , Performance-Enhancing Substances/administration & dosage , Caffeine/administration & dosage , Creatine/administration & dosage , Sodium Bicarbonate/administration & dosage , beta-Alanine/administration & dosage , beta-Alanine/pharmacology , Adult , Male , Female , Randomized Controlled Trials as Topic
2.
J Vasc Surg Venous Lymphat Disord ; 12(4): 101848, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38346475

ABSTRACT

BACKGROUND: Thrombolytic therapy is effective method in the high-risk acute pulmonary embolism (PE) treatment. Reduced-dose thrombolysis (RDT) plus oral anticoagulation therapy is effective and safe method in the moderate and severe PE treatment. It is leading to good early and intermediate-term outcomes. In the RE-COVER and RE-COVER II studies, dabigatran showed similar effectiveness as warfarin in the treatment of acute PE. Dabigatran leads to fewer hemorrhagic complications and is not inferior in efficacy to warfarin in the prevention of PE after mechanical fragmentation and RDT (catheter-directed treatment [CDT]+RDT) in patients with high and intermediate to high PE risk. We sought to evaluate the efficacy and safety (incidence of clinically significant recurrence of venous thromboembolic complications and deaths) during a 6-month course of treatment with dabigatran or warfarin in patients with high and intermediate to high acute PE risk after endovascular mechanical thrombus fragmentation procedure with RDT (CDT+RDT). METHODS: The RE-SPIRE is a prospective, multicenter randomized double-arm study. Over a 5-year period, 66 consecutive patients with symptomatic high and intermediate to high PE risk after endovascular mechanical thrombus fragmentation procedure with RDT (CDT+RDT) were randomized into two groups within the next 48 hours. The first group continued treatment with dabigatran 150 mg twice a day for 6 months; the second group continued treatment with warfarin under the control of international normalized ratio (2.0-3.0) for 6 months. Both groups received low molecular weight heparins for 2 days after surgery. Then, group 1 continued to receive low molecular-weight-heparin for 5 to 7 days, followed by a switch to dabigatran at a dosage of 150 mg two times a day. Group 2 received both low-molecular-weight heparin and warfarin up to an international normalized ratio of >2.0, followed by heparin withdrawal. The follow-up period was 6 months. RESULTS: There were 63 patients who completed the study (32 in the dabigatran group and 31 in the warfarin group). In both groups, there was a statistically significant decrease in the mean pulmonary artery pressure. The mean pulmonary artery pressure at the 6-month follow-up after surgery was 24 mm Hg (interquartile range, 20.3-29.25 mm Hg) in the dabigatran group and 23 mm Hg (interquartile range, 20.0-26.3 mm Hg) in the warfarin group. The groups did not differ statistically in the deep vein thrombosis dynamics. Partial recanalization occurred in 52.0% vs 73.1% in the dabigatran and warfarin groups, respectively (P = .15). Complete recanalization occurred in 28.0% vs 19.2% in the dabigatran and warfarin groups, respectively (P = .56). The groups did not differ in the frequency of major bleeding events according to the International Society for Thrombosis and Hemostasis (0% vs 3.2% in the dabigatran and warfarin groups, respectively; P = 1.00). However, there were more nonmajor bleeding events in the warfarin group than in the dabigatran group (16.1% vs 0%, respectively; P = .02). CONCLUSIONS: The results of the study show that dabigatran is comparable in effectiveness to warfarin. Dabigatran has greater safety in comparison with warfarin in the occurrence of all cases of bleeding in the postoperative and long-term periods. Thus, dabigatran may be recommended for the treatment and prevention of PE after CDT with RDT in patients with high and intermediate to high PE risk.


Subject(s)
Anticoagulants , Antithrombins , Dabigatran , Pulmonary Embolism , Thrombolytic Therapy , Warfarin , Humans , Dabigatran/adverse effects , Dabigatran/administration & dosage , Warfarin/adverse effects , Warfarin/administration & dosage , Pulmonary Embolism/prevention & control , Pulmonary Embolism/drug therapy , Pulmonary Embolism/etiology , Male , Female , Anticoagulants/adverse effects , Anticoagulants/administration & dosage , Middle Aged , Thrombolytic Therapy/adverse effects , Aged , Treatment Outcome , Prospective Studies , Antithrombins/adverse effects , Antithrombins/administration & dosage , Acute Disease , Time Factors , Recurrence , Adult , beta-Alanine/analogs & derivatives , beta-Alanine/adverse effects , beta-Alanine/administration & dosage , Risk Factors , Hemorrhage/chemically induced , International Normalized Ratio
4.
Cornea ; 40(10): 1225-1228, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34481406

ABSTRACT

ABSTRACT: The current understanding on the clinical efficacy of Rho-associated protein kinase (ROCK) inhibitor for treating Fuchs endothelial corneal dystrophy is summarized to clarify whether the "off-label" ROCK-inhibitor eye-drop application are appropriate. ROCK-inhibitor eye drops may eventually be deemed a cutting-edge therapy for Fuchs endothelial corneal dystrophy patients with acute corneal endothelial defect.


Subject(s)
Fuchs' Endothelial Dystrophy/drug therapy , Protein Kinase Inhibitors/administration & dosage , rho-Associated Kinases/antagonists & inhibitors , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/administration & dosage , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/analogs & derivatives , Administration, Ophthalmic , Benzoates/administration & dosage , Clinical Trials as Topic , Humans , Isoquinolines/administration & dosage , Ophthalmic Solutions , Sulfonamides/administration & dosage , Treatment Outcome , beta-Alanine/administration & dosage , beta-Alanine/analogs & derivatives
5.
Nutrients ; 13(8)2021 Jul 25.
Article in English | MEDLINE | ID: mdl-34444703

ABSTRACT

Supplementation with ß-alanine is becoming a common practice in high-performance athletes. The purpose of the present study was to investigate the effects of a one-week high-dose ß-alanine loading phase employing a sustained-release powder on preserving the time-trial performance capacity of world tour cyclists during overreaching training. Per day, 20 g of sustained-release ß-alanine was administered during one week (7 days) of intensive team training camp in a randomised balanced placebo-controlled parallel trial design, with six participants in each ß-alanine (BA) or placebo (PLA) group. A 10-min time trial (10' TT) was carried out to analyse performance and biochemical variables. Anthropometry, paresthesia, and adverse event data were also collected. Power-based relative training load was quantified. Compared to placebo, the BA improved mean power (6.21%, 37.23 W; 95% CI: 3.98-70.48 W, p = 0.046), distance travelled (2.16%, p = 0.046) and total work (4.85%, p = 0.046) without differences in cadence (p = 0.506) or RPE. Lactate (p = 0.036) and anion gap (p = 0.047) were also higher in the BA group, without differences in pH or Bicarbonate. High daily and single doses were well tolerated. One-week high-dose ß-alanine loading with a sustained-release powder blend can help attenuate 10' TT performance losses of world tour cyclists due to intensive training.


Subject(s)
Athletic Performance/physiology , Bicycling/physiology , Dietary Supplements , beta-Alanine/administration & dosage , Adult , Double-Blind Method , Humans , Male , Powders , Young Adult
6.
J Int Soc Sports Nutr ; 18(1): 48, 2021 Jun 14.
Article in English | MEDLINE | ID: mdl-34127014

ABSTRACT

BACKGROUND: This study aimed to investigate the effect of multi-ingredient intra- (BA) versus extra- (ALK) cellular buffering factor supplementation, combined with the customary intake of branched-chain amino acids (BCAA) and creatine malate (TCM), on body composition, exercise variables, and biochemical and hematological parameters in 9 elite taekwondo athletes. METHODS: Eight-week randomized double-blind crossover BA (5.0 g·day-1 of ß-alanine) versus ALK (0.07 g·kgFFM-1·day-1 of sodium bicarbonate) supplementation combined with BCAA (0.2 g·kgFFM-1·day-1) and TCM (0.05 g·kgFFM-1·day-1) during a standard 8-week taekwondo training period was implemented. In the course of the experiment, body composition (dual X-ray absorptiometry), aerobic capacity (ergospirometric measurements during an incremental treadmill test until exhaustion), and exercise blood biomarkers concentrations were measured. Data were analyzed using repeated measures within-between interaction analysis of variance with the inclusion of experimental supplementation order. RESULTS: The maximum post-exercise blood ammonia concentration decreased in both groups after supplementation (from 80.3 ± 10.6 to 72.4 ± 10.2 µmol∙L-1, p = 0.013 in BA; from 81.4 ± 8.7 to 74.2 ± 8.9 µmol∙L-1, p = 0.027 in ALK), indicating reduced exercise-related adenosine triphosphate degradation. However, no differences were found in body composition, aerobic capacity, blood lactate concentration, and hematological parameters after neither BA (combined with BCAA and TCM) nor ALK (combined with BCAA and TCM) supplementation. CONCLUSIONS: In highly trained taekwondo athletes, neither extra- nor intracellular buffering enhancement resulting from BA and ALK supplementation, combined with BCAA and TCM treatment, affects body mass and composition, maximum oxygen uptake, and hematological indices, even though certain advantageous metabolic adaptations can be observed.


Subject(s)
Amino Acids, Branched-Chain/administration & dosage , Ammonia/blood , Athletic Performance/physiology , Creatine/administration & dosage , Dietary Supplements , Martial Arts/physiology , Sodium Bicarbonate/administration & dosage , beta-Alanine/administration & dosage , Adaptation, Physiological , Biomarkers/blood , Body Composition , Cross-Over Studies , Double-Blind Method , Humans
7.
Int J Sport Nutr Exerc Metab ; 31(4): 305-313, 2021 07 01.
Article in English | MEDLINE | ID: mdl-34098531

ABSTRACT

Currently, little is known about the extent of interindividual variability in response to beta-alanine (BA) supplementation, nor what proportion of said variability can be attributed to external factors or to the intervention itself (intervention response). To investigate this, individual participant data on the effect of BA supplementation on a high-intensity cycling capacity test (CCT110%) were meta-analyzed. Changes in time to exhaustion (TTE) and muscle carnosine were the primary and secondary outcomes. Multilevel distributional Bayesian models were used to estimate the mean and SD of BA and placebo group change scores. The relative sizes of group SDs were used to infer whether observed variation in change scores were due to intervention or non-intervention-related effects. Six eligible studies were identified, and individual data were obtained from four of these. Analyses showed a group effect of BA supplementation on TTE (7.7, 95% credible interval [CrI] [1.3, 14.3] s) and muscle carnosine (18.1, 95% CrI [14.5, 21.9] mmol/kg DM). A large intervention response variation was identified for muscle carnosine (σIR = 5.8, 95% CrI [4.2, 7.4] mmol/kg DM) while equivalent change score SDs were shown for TTE in both the placebo (16.1, 95% CrI [13.0, 21.3] s) and BA (15.9, 95% CrI [13.0, 20.0] s) conditions, with the probability that SD was greater in placebo being 0.64. In conclusion, the similarity in observed change score SDs between groups for TTE indicates the source of variation is common to both groups, and therefore unrelated to the supplement itself, likely originating instead from external factors such as nutritional intake, sleep patterns, or training status.


Subject(s)
Bicycling/physiology , Carnosine/metabolism , Dietary Supplements , Exercise Tolerance/physiology , Muscle, Skeletal/metabolism , beta-Alanine/administration & dosage , Bayes Theorem , Bias , Double-Blind Method , Humans , Randomized Controlled Trials as Topic , Sports Nutritional Physiological Phenomena , Time Factors
8.
Am J Physiol Regul Integr Comp Physiol ; 320(6): R824-R832, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33789445

ABSTRACT

To examine the role of chronic (in)activity on muscle carnosine (MCarn) and how chronic (in)activity affects MCarn responses to ß-alanine supplementation in spinal cord-injured athletes, 16 male athletes with paraplegia were randomized (2:1 ratio) to receive ß-alanine (n = 11) or placebo (PL, n = 5). They consumed 6.4 g/day of ß-alanine or PL for 28 days. Muscle biopsies of the active deltoid and the inactive vastus lateralis (VL) were taken before and after supplementation. MCarn in the VL was also compared with the VL of a group of individuals without paraplegia (n = 15). MCarn was quantified in whole muscle and in pools of individual fibers by high-performance liquid chromatography. MCarn was higher in chronically inactive VL vs. well-trained deltoid (32.0 ± 12.0 vs. 20.5 ± 6.1 mmol/kg DM; P = 0.018). MCarn was higher in inactive vs. active VL (32.0 ± 12.0 vs. 21.2 ± 7.5 mmol/kg DM; P = 0.011). In type-I fibers, MCarn was significantly higher in the inactive VL than in the active deltoid (38.3 ± 4.7 vs. 27.3 ± 11.8 mmol/kg DM, P = 0.014). MCarn increased similarly between inactive VL and active deltoid in the ß-alanine group (VL: 68.9 ± 55.1%, P = 0.0002; deltoid: 90.5 ± 51.4%, P < 0.0001), with no changes in the PL group. MCarn content was higher in the inactive VL than in the active deltoid and the active VL, but this is probably a consequence of fiber type shift (type I to type II) that occurs with chronic inactivity. Chronically inactive muscle showed an increase in MCarn after BA supplementation equally to the active muscle, suggesting that carnosine accretion following ß-alanine supplementation is not influenced by muscle inactivity.


Subject(s)
Carnosine/metabolism , Homeostasis/physiology , Muscle, Skeletal/physiopathology , Spinal Cord Injuries/physiopathology , Spinal Cord/physiopathology , Athletes , Dietary Supplements , Humans , Spinal Cord/drug effects , beta-Alanine/administration & dosage , beta-Alanine/pharmacology
9.
J Sports Sci ; 39(11): 1295-1301, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33491594

ABSTRACT

The availability of dietary beta-alanine (BA) is the limiting factor in carnosine synthesis within human muscle due to its low intramuscular concentration and substrate affinity. Carnosine can accept hydrogen ions (H+), making it an important intramuscular buffer against exercise-induced acidosis. Metabolite accumulation rate increases when exercising in hypoxic conditions, thus an increased carnosine concentration could attenuate H+ build-up when exercising in hypoxic conditions. This study examined the effects of BA supplementation on high intensity cycling capacity in normoxia and hypoxia. In a double-blind design, nineteen males were matched into a BA group (n = 10; 6.4 g·d-1) or a placebo group (PLA; n = 9) and supplemented for 28 days, carrying out two pre- and two post-supplementation cycling capacity trials at 110% of powermax, one in normoxia and one in hypoxia (15.5% O2). Hypoxia led to a 9.1% reduction in exercise capacity, but BA supplementation had no significant effect on exercise capacity in normoxia or hypoxia (P > 0.05). Blood lactate accumulation showed a significant trial x time interaction post-supplementation (P = 0.016), although this was not significantly different between groups. BA supplementation did not increase high intensity cycling capacity in normoxia, nor did it improve cycling capacity in hypoxia even though exercise capacity was reduced under hypoxic conditions.


Subject(s)
Bicycling/physiology , Carnosine/biosynthesis , Dietary Supplements , Hypoxia/metabolism , Muscle, Skeletal/metabolism , beta-Alanine/metabolism , Acidosis, Lactic/blood , Analysis of Variance , Double-Blind Method , Exercise Test , Exercise Tolerance/physiology , Humans , Hydrogen/metabolism , Male , Performance-Enhancing Substances/administration & dosage , Performance-Enhancing Substances/metabolism , Placebos , Single-Blind Method , Young Adult , beta-Alanine/administration & dosage
10.
Cornea ; 40(8): 1048-1054, 2021 08 01.
Article in English | MEDLINE | ID: mdl-33369939

ABSTRACT

PURPOSE: To describe cases in which netarsudil ophthalmic solution 0.02% precipitated reversible, reticular cystic epithelial edema. METHODS: A retrospective case review at the Brooklyn Veteran's Association Hospital of patients with corneal stromal edema that were treated with netarsudil and subsequently developed cystic epithelial edema. RESULTS: Four male patients with a mean age of 72 ± 8.0 years developed a reticular, honeycomb-like pattern of epithelial edema located in the interpalpebral and inferior cornea. In 3 of 4 patients, epithelial edema arose within 1 month compared with 2 months in 1 patient. New epithelial cysts did not correlate with worsening central corneal thickness and best spectacle-corrected visual acuity in every patient, which was likely due to the location of the cysts. Two of 4 patients developed increased central corneal thickness with worsening best spectacle-corrected visual acuity. In comparison, 1 patient had improvement in both parameters, whereas 1 patient had no significant change. In all cases, there was resolution of the epithelial cysts after discontinuation of netarsudil. CONCLUSIONS: Although rho-kinase inhibitors have been suggested to improve endothelial function, we have documented worsening epithelial cysts in a subset of patients with pre-existing corneal edema. These effects of netarsudil were transient and resolved after discontinuing treatment within 2 weeks in most patients. We hypothesize that the incidence of this adverse finding is more common than previously believed. Nevertheless, large-scale studies are needed to accurately report on the incidence and clinical significance of this novel finding.


Subject(s)
Benzoates/administration & dosage , Corneal Edema/drug therapy , Epithelium, Corneal/pathology , Intraocular Pressure/drug effects , Visual Acuity , beta-Alanine/analogs & derivatives , Aged , Aged, 80 and over , Corneal Edema/pathology , Corneal Edema/physiopathology , Epithelium, Corneal/drug effects , Humans , Male , Ophthalmic Solutions/administration & dosage , Retrospective Studies , Slit Lamp Microscopy , beta-Alanine/administration & dosage , rho-Associated Kinases/antagonists & inhibitors
11.
Vet Ophthalmol ; 24 Suppl 1: 87-95, 2021 Mar.
Article in English | MEDLINE | ID: mdl-31908139

ABSTRACT

OBJECTIVES: To evaluate the effect of QD or BID 0.02% netarsudil ophthalmic solution (Aerie Pharmaceuticals) on intraocular pressure (IOP) in normotensive dogs and to describe any adverse effects. ANIMALS STUDIED: Normotensive Labrador retriever dogs were included in this study: 10 received netarsudil in one eye and artificial tears in the contralateral eye QD, and 10 received netarsudil in one eye and artificial tears in the contralateral eye BID. PROCEDURES: Intraocular pressure curves were acquired over a 3-day acclimation period, 5-day dosing period (QD or BID-10 dogs/group), and 3-day recovery period. Toxicity was assessed daily using slit-lamp biomicroscopy and the semiquantitative preclinical ocular toxicology scoring system. RESULTS: Once-daily dosing did not lower IOP over the entire 5-day dosing period (95% CI 0.1 to -0.9 mm Hg, P = .20) or on the last day of dosing (95% CI 0.4 to -0.9 mm Hg, P = .65). Twice-daily dosing resulted in a statistically significant, but clinically unimportant, IOP reduction over the entire 5-day dosing period (-0.6 mm Hg; 95% CI 0.05 to -1.1 mm Hg, P = .02) and on the last day of dosing (-0.9 mm Hg; 95% CI 0.2 to -1.5 mm Hg, P = .003). Adverse events were limited to transient mild-to-moderate conjunctival hyperemia during the dosing phase in eyes receiving netarsudil vs control (P < .0001). CONCLUSIONS: Netarsudil 0.02% ophthalmic solution twice daily resulted in a small, statistically significant, but clinically unimportant, IOP reduction in normotensive dogs. Future studies should investigate efficacy in glaucomatous dogs.


Subject(s)
Benzoates/pharmacology , Intraocular Pressure/drug effects , beta-Alanine/analogs & derivatives , Animals , Benzoates/administration & dosage , Benzoates/adverse effects , Dogs , Dose-Response Relationship, Drug , Female , Male , Ophthalmic Solutions/administration & dosage , Ophthalmic Solutions/adverse effects , Ophthalmic Solutions/pharmacology , Prospective Studies , beta-Alanine/administration & dosage , beta-Alanine/adverse effects , beta-Alanine/pharmacology
12.
Vet Ophthalmol ; 24 Suppl 1: 75-86, 2021 Mar.
Article in English | MEDLINE | ID: mdl-31872953

ABSTRACT

OBJECTIVE: To evaluate safety and efficacy of topically administered 0.02% netarsudil ophthalmic solution (Rhopressa™; Aerie Pharmaceutical) in normal and glaucomatous dogs with ADAMTS10-open-angle glaucoma (ADAMTS10-OAG). ANIMALS STUDIED: Five normal and 5 glaucomatous Beagle dogs with ADAMTS10-OAG. PROCEDURES: In each dog, left or right eye was randomly selected for netarsudil treatment. Contralateral eyes were sham-treated with balanced salt solution (BSS). Following a 1-week baseline period, dogs were treated once daily (q24h) during week 2, and twice daily (q12h) during week 3; week 4 served as washout period. Efficacy was measured by diurnal intraocular pressure (IOP) and pupil diameter. Safety was assessed by routine ophthalmic examination, gonioscopy, and pachymetry. Differences in least square means of quantitative outcome measures were compared between netarsudil and BSS sham-treated eyes by linear Gaussian model. RESULTS: Baseline IOPs were 18.5 ± 0.5 mm Hg (mean ± SEM) in normal and 27.8 ± 1.0 mm Hg in OAG dogs. Even though mean IOPs were lower in netarsudil- vs sham-treated eyes, the overall differences were neither significant nor clinically relevant, regardless of treatment frequency (q24h-normal: sham 16.4 ± 1.1 mm Hg vs treatment 15.6 ± 1.0 mm Hg; q24hr-OAG: sham 25.8 ± 2.3 mm Hg vs. treatment 25.7 ± 2.4 mm Hg; q12hr-normal: sham 15.4 ± 0.8 mm Hg vs. treatment 14.4 ± 0.8 mm Hg; q12hr-OAG: sham 26.3 ± 1.7 mm Hg vs. treatment 25.4 ± 1.8 mm Hg). Netarsudil administration was well tolerated but resulted in significant, moderate-to-severe conjunctival hyperemia (P < .001). CONCLUSIONS: Once or twice daily administration of netarsudil resulted in marginal and clinically irrelevant IOP decreases in normal and OAG-affected dogs. Except for conjunctival hyperemia, the drug was well tolerated.


Subject(s)
Benzoates/therapeutic use , Dog Diseases/drug therapy , Glaucoma, Open-Angle/veterinary , beta-Alanine/analogs & derivatives , Administration, Ophthalmic/veterinary , Animals , Benzoates/administration & dosage , Benzoates/adverse effects , Dogs , Female , Glaucoma, Open-Angle/drug therapy , Intraocular Pressure/drug effects , Male , Pupil/drug effects , Treatment Outcome , beta-Alanine/administration & dosage , beta-Alanine/adverse effects , beta-Alanine/therapeutic use
13.
J Diet Suppl ; 18(2): 147-168, 2021.
Article in English | MEDLINE | ID: mdl-32138563

ABSTRACT

Introduction: ß-alanine (BA) supplementation may improve cognition and mitigate symptoms of anxiety and depression associated with aging, neurological disorders, and physical exertion, which has been attributed to increases in brain carnosine and/or brain-derived neurotropic factor (BDNF). BA also provides beneficial effects on cognition, mood, and physical performance during military operations; however, whether BA can attenuate mood disruptions and cognitive dysfunction associated with the anticipatory stress prior to simulated military operations is unknown.Purpose: The present study examined the effects of 14 days of BA (12 g·day-1) supplementation on cognitive function, mood, and circulating BDNF concentrations in recreationally-active, healthy males with limited inflammation and oxidative stress prior to a 24h simulated military operation.Methods: Participants were randomized into BA (n = 10) or placebo (n = 9; PL) for 14 days. Cognitive function, mood, and circulating BDNF were assessed before (PRE) and after (POST) supplementation. Cognition was assessed via multiple object tracking (Neurotracker™), visuomotor reaction time (Dynavision™), mathematical processing (Serial Subtraction Test), and neuropsychological assessments (ANAM™). Mood was assessed using the Profile of Mood States (POMS) questionnaire. After POST testing, subjects underwent a 24h simulated military operation.Results: No change in measures of cognitive function or BDNF concentrations were observed (p > 0.05). However, BA experienced significant reductions (p = 0.046) in subjective feelings of depression, while PL experienced significant reductions (p = 0.021) in feelings of vigor from PRE to POST.Conclusions: High-dose, short-duration BA supplementation does not appear to affect cognitive function or circulating BDNF, but may mitigate the onset of negative mood states in healthy, recreationally-active males prior to a simulated military operation.


Subject(s)
Affect/drug effects , Brain-Derived Neurotrophic Factor , Cognition , Military Personnel , Stress, Psychological , beta-Alanine/administration & dosage , Brain , Brain-Derived Neurotrophic Factor/blood , Cognition/drug effects , Dietary Supplements , Humans , Male
14.
J Sports Med Phys Fitness ; 61(12): 1605-1612, 2021 Dec.
Article in English | MEDLINE | ID: mdl-33305552

ABSTRACT

BACKGROUND: Beta-alanine has become a dietary supplement widely used by athletes due to its ergogenic effect. However, there is still no consensus on the performance benefit of beta-alanine on exercise lasting longer than ten minutes. The present study aimed to evaluate the effect of beta-alanine supplementation on running performance and the expression of TauT and PAT1. METHODS: This double-blind, randomized study enrolled 16 long-distance runners (37±8 years) who were randomly allocated to two groups: placebo (PLA) and beta-alanine (BA) (4.8 g/day 1) for four weeks. Maximal oxygen consumption, anthropometry, body composition, and food intake were determined. Before and after the intervention, the athletes undertook a 5000 m running time trial. Venous blood (TauT and PAT1 expressions) and ear lobe capillary blood (lactate) collected before and after exercise. Between tests, we monitored the training variables. RESULTS: The results were analyzed by t-tests and an ANOVA of repeated measures, with Sidak's post hoc (P<0.05). PLA exhibited lower body fat than BA (8.7±2.2 vs. 11.5±2.8%, P=0.04). After supplementation, there was an increase in PAT1 expression in BA when compared to PLA (1.17±0.47 vs. 0.77±0.18, P=0.04). No significant differences were shown for the 5000 m running time in PLA (PRE: 1128±72; POST: 1123±72s) and BA (PRE: 1107±95; POST: 1093±86s). CONCLUSIONS: Although beta-alanine supplementation increased PAT1 expression, there was no statistically significant improvement in 5000 m running performance. However, individual responses should be considered as the BA showed a higher delta than the PLA.


Subject(s)
Amino Acid Transport Systems/metabolism , Athletic Performance , Performance-Enhancing Substances , Running , Symporters/metabolism , beta-Alanine/administration & dosage , Adult , Dietary Supplements , Double-Blind Method , Humans , Lactic Acid , Membrane Glycoproteins/metabolism , Membrane Transport Proteins/metabolism , Middle Aged , Performance-Enhancing Substances/administration & dosage , Physical Endurance , Sports Nutritional Physiological Phenomena
15.
Med Sci Sports Exerc ; 53(5): 1079-1088, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33148972

ABSTRACT

PURPOSE: This study aimed to describe the kinetics of carnosine washout in human skeletal muscle over 16 wk. METHODS: Carnosine washout kinetics were studied in 15 young, physically active omnivorous men randomly assigned to take 6.4 g·d-1 of ß-alanine (n = 11) or placebo (n = 4) for 8 wk. Muscle carnosine content (M-Carn) was determined before (PRE), immediately after (POST), and 4, 8, 12, and 16 wk after supplementation. High-intensity exercise tests were performed at these same time points. Linear and exponential models were fitted to the washout data, and the leave-one-out method was used to select the model with the best fit for M-Carn decay data. Repeated-measures correlation analysis was used to assess the association between changes in M-Carn and changes in performance. RESULTS: M-Carn increased from PRE to POST in the ß-alanine group only (+91.1% ± 29.1%; placebo, +0.04% ± 10.1%; P < 0.0001). M-Carn started to decrease after cessation of ß-alanine supplementation and continued to decrease until week 16 (POST4, +59% ± 40%; POST8, +35% ± 39%; POST12, +18% ± 32%; POST16, -3% ± 24% of PRE M-Carn). From week 12 onward, M-Carn was no longer statistically different from PRE. Both linear and exponential models displayed very similar fit and could be used to describe carnosine washout, although the linear model presented a slightly better fit. The decay in M-Carn was mirrored by a similar decay in high-intensity exercise tolerance; M-Carn was moderately and significantly correlated with total mechanical work done (r = 0.505; P = 0.032) and time to exhaustion (r = 0.72; P < 0.001). CONCLUSIONS: Carnosine washout takes 12-16 wk to complete, and it can be described either by linear or exponential curves. Changes in M-Carn seem to be mirrored by changes in high-intensity exercise tolerance. This information can be used to optimize ß-alanine supplementation strategies.


Subject(s)
Carnosine/metabolism , Exercise Tolerance/physiology , Exercise/physiology , Muscle, Skeletal/metabolism , beta-Alanine/administration & dosage , Adult , Dietary Supplements , Exercise Test , Humans , Linear Models , Male , Time Factors , Young Adult
16.
J Sports Med Phys Fitness ; 61(1): 37-43, 2021 01.
Article in English | MEDLINE | ID: mdl-33092320

ABSTRACT

BACKGROUND: Chronic supplementation with carnosine and ß-alanine (Carn-ßA) has been proposed to improve muscle contractility and reduce muscle fatigue mainly through an increase in intracellular pH buffering capacity. However, the acute ergogenic effects of Carn-ßA supplementation are poorly investigated. This study aimed at evaluating the acute effects of a single Carn-ßA supplementation on the cardiorespiratory and metabolic response during a ramp cycle-ergometric test. METHODS: This randomized, double-blind, placebo-controlled study, involved 10 healthy males (age: 22.2±1.9 years, body mass: 72.5±7.9 kg, stature: 1.72±0.08 m, Body Mass Index: 24.47±1.91 kg/m2, mean±standard deviation). All the participants performed two maximal incremental ramp tests on a cycle ergometer, with a prior randomized assumption of 2.5 g L-carnosine plus 2.5 g ß-alanine (Carn-ßA) or placebo (PLA). During exercise, gas exchange parameters were measured breath-by-breath, heart rate was monitored by electrocardiography and rate perceived exertion was determined on Borg scales. From the ramp test, peak cardiorespiratory and metabolic parameters and ventilatory thresholds (VT1 and VT2) were calculated offline. RESULTS: No differences between the experimental conditions emerged at peak exercise. However, despite acute Carn-ßA supplementation did not affect the single ventilatory thresholds, the compensated portion of the ramp test (i.e. the difference between VT2 and VT1) was significantly larger (P=0.043) in Carn-ßA. CONCLUSIONS: These findings demonstrate a positive effect of acute Carn-ßA supplementation on the compensated part of the exercise. This should be taken into account by nutritionists and athletes searching for nutritional supplements, when a quick effect based on an acute dose is required.


Subject(s)
Dietary Supplements , beta-Alanine/pharmacology , Adult , Carnosine/metabolism , Carnosine/pharmacology , Double-Blind Method , Exercise/physiology , Exercise Test , Heart Rate/drug effects , Humans , Male , Muscle Fatigue/drug effects , Muscle, Skeletal/physiology , Performance-Enhancing Substances/pharmacology , Respiration/drug effects , Young Adult , beta-Alanine/administration & dosage
17.
Am J Ophthalmol ; 222: 382-387, 2021 02.
Article in English | MEDLINE | ID: mdl-33045216

ABSTRACT

PURPOSE: To assess whether prophylactic use of netarsudil 0.02% ophthalmic solution reduces the risk of intraocular pressure (IOP) elevation associated with prolonged use of topical corticosteroids to prevent cornea transplantation rejection. DESIGN: Prospective, randomized clinical trial. METHODS: In this study, 120 subjects were randomized to use netarsudil (off-label) or placebo once daily for 9 months after Descemet membrane endothelial keratoplasty, and 71 fellow eyes were enrolled and assigned to the opposite treatment arm. Participants concurrently used topical prednisolone acetate 1% 4× daily for 3 months, 3× daily for a month, twice daily for a month, and once daily for 4 months. The main outcome was IOP elevation (defined as IOP ≥24 mm Hg or an increase of ≥10 mm Hg over baseline) assessed by Kaplan-Meier and proportional hazards analyses, taking loss to follow-up into consideration. RESULTS: Overall, 95 eyes were assigned to netarsudil and 96 to placebo; 15 eyes (16%) were withdrawn early from the netarsudil arm because of ocular irritation. The rate of IOP elevation was 14% with netarsudil and 21% with placebo (relative risk: 0.6; 95% confidence interval: 0.3-1.3; P = .23). IOP was >30 mm Hg in 7.8% assigned to netarsudil versus 7.4% assigned to placebo (P = .84). Median 6-month central endothelial cell loss was 31% versus 29% with netarsudil versus placebo, respectively (P = .49). CONCLUSIONS: Netarsudil did not produce a statistically significant reduction in the risk of steroid-induced IOP elevation after corneal transplantation relative to placebo.


Subject(s)
Benzoates/administration & dosage , Intraocular Pressure/drug effects , Ocular Hypertension/prevention & control , Prednisolone/analogs & derivatives , beta-Alanine/analogs & derivatives , Adult , Aged , Aged, 80 and over , Double-Blind Method , Female , Follow-Up Studies , Glucocorticoids/adverse effects , Humans , Male , Middle Aged , Ocular Hypertension/chemically induced , Ocular Hypertension/physiopathology , Ophthalmic Solutions/administration & dosage , Prednisolone/adverse effects , Prospective Studies , beta-Alanine/administration & dosage
18.
Nutrients ; 12(12)2020 Dec 18.
Article in English | MEDLINE | ID: mdl-33352860

ABSTRACT

The aim of this study was to analyze the anthropometric characteristics and sport supplement (SS) consumption patterns of heavyweight and lightweight international rowers. Methods: The 13 heavyweights (11 males) and seven lightweights (five males) of the Spanish National Rowing Team were recruited for the study. Body composition was measured by bio-impedance analysis, and the questionnaire used in this investigation was previously validated to assess SS consumption. According to anthropometrics parameters, it was reported that male heavyweight rowers were heavier (p < 0.001) and taller (p < 0.001), but no statistical differences were reported for % body fat (p = 0.104) or % lean body mass (p = 0.161). All rowers reported consumption of at least one SS. Based on the Australian Institute of Sport's classification, higher medical supplement consumption was observed when comparing heavyweight rowers to lightweight rowers (2.5 ± 1.1 vs. 1.7 ± 0.5, p = 0.040). There were no differences in the totals of group A (strong scientific evidence for sports scenarios, p = 0.069), group B (emerging scientific support, deserving of further research, p = 0.776), or group C (scientific evidence not supportive of benefit and/or security amongst athletes, p = 0.484). The six most consumed SSs were iron (85%), caffeine (85%), ß-alanine (85%), energy bars (85%), vitamin supplements (80%), and isotonic drinks (80%), with no statistical differences between heavyweight and lightweight rowers (p > 0.05). These results suggest that the absence of differences in body composition (expressed as a percentage) do not represent anthropometric disadvantages for heavyweight rowers. In addition, SS consumption was similar between rowers, reporting only higher medical supplement consumption in heavyweight rowers.


Subject(s)
Body Composition , Dietary Supplements , Sports Nutritional Physiological Phenomena , Water Sports , Adiposity , Anthropometry , Athletes , Body Height , Body Weight , Caffeine/administration & dosage , Electric Impedance , Energy Intake , Female , Humans , Iron, Dietary/administration & dosage , Male , Spain , Vitamins/administration & dosage , Young Adult , beta-Alanine/administration & dosage
19.
Ophthalmol Glaucoma ; 3(6): 421-425, 2020.
Article in English | MEDLINE | ID: mdl-33250082

ABSTRACT

PURPOSE: To describe the changes in endothelial cell density (ECD), the coefficient of variation (CV), and the percent of hexagonal cells (%HEX) after 3 months of therapy with netarsudil (Rhopressa; Aerie Pharmaceuticals Inc, Durham, NC) 0.02% dosed once daily (QD) or twice daily (BID) and to compare these changes with those seen with timolol 0.5% BID in eyes with ocular hypertension (OHTN) or open-angle glaucoma (OAG). DESIGN: Post hoc analysis of data from a phase 3 evaluation of the intraocular pressure (IOP)-lowering efficacy and safety of netarsudil 0.02% versus timolol 0.5%. PARTICIPANTS: A subset of study subjects underwent corneal endothelial cell imaging by specular microscopy at baseline and after 3 months of therapy. METHODS: Images were evaluated in a masked fashion at an independent reading center. The ECD, CV, and %HEX were determined using a standardized protocol for image analysis. MAIN OUTCOME MEASURES: Changes in ECD, CV, and %HEX from baseline to 3 months were compared between treatment groups using 2-sample t tests. RESULTS: Data from 386 subjects from whom analyzable specular microscopy images were obtained at both baseline and month 3 were included in this analysis. Mean ECD, CV, and %HEX values were comparable between groups at baseline. There were no statistically significant between-group differences in changes from baseline to month 3 in ECD, CV, or %HEX between either of the netarsudil groups and the timolol group. Within groups, CV declined in a statistically significant fashion from baseline to month 3 in all 3 groups by 1.4% to 2.1% (P < 0.001), and %HEX increased by a statistically significant amount (0.7%, P = 0.030) in the timolol group. These small changes were unlikely to be of clinical significance. No statistically significant changes in ECD were seen in any group. CONCLUSIONS: Netarsudil 0.02% showed no clinically significant effects on ECD, CV, or %HEX when dosed QD or BID for 3 months in eyes with OHTN or OAG.


Subject(s)
Benzoates/administration & dosage , Endothelium, Corneal/drug effects , Glaucoma/drug therapy , Intraocular Pressure/physiology , Ocular Hypertension/drug therapy , beta-Alanine/analogs & derivatives , Aged , Double-Blind Method , Endothelium, Corneal/pathology , Female , Follow-Up Studies , Glaucoma/diagnosis , Glaucoma/physiopathology , Humans , Male , Middle Aged , Ocular Hypertension/diagnosis , Ocular Hypertension/physiopathology , Ophthalmic Solutions/administration & dosage , Prospective Studies , Time Factors , Treatment Outcome , beta-Alanine/administration & dosage
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