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Frontiers in Sports and Active Living 2022The objective of the present study is to review and meta-analyze the effect of E-cycling on health outcomes. We included longitudinal experimental and cohort studies...
The objective of the present study is to review and meta-analyze the effect of E-cycling on health outcomes. We included longitudinal experimental and cohort studies investigating the effect of E-cycling on health outcomes. The studies were identified from the seven electronic databases: Web of Science, Scopus, Medline, Embase, PsycINFO, Cinahl and SportDiscus and risk of bias was assessed with the revised Cochrane Collaboration Risk of Bias Tool (RoB2). We performed meta-analysis with random effects models on outcomes presented in more than one study. Our study includes one randomized controlled trial, five quasi experimental trials and two longitudinal cohort studies. The trials included 214 subjects of whom 77 were included in control groups, and the cohort studies included 10,222 respondents at baseline. Maximal oxygen consumption and maximal power output were assessed in four and tree trials including 78 and 57 subjects, respectively. E-cycling increased maximal oxygen consumption and maximal power output with 0.48 SMD (95%CI 0.16-0.80) and 0.62 SMD (95%CI 0.24-0.99). One trial reported a decrease in 2-h post plasma glucoses from 5.53 ± 1.18 to 5.03 ± 0.91 mmol L and one cohort study reported that obese respondents performed 0.21 times more trips on E-bike than respondents with normal weight. All the included studies had a high risk of bias due to flaws in randomization. However, the outcomes investigated in most studies showed that E-cycling can improve health.
PubMed: 36339641
DOI: 10.3389/fspor.2022.1031004 -
Cardiology 2023Space travel imposes significant gravitational and radiation stress on both cellular and systemic physiology, resulting in myriad cardiovascular changes that have not...
INTRODUCTION
Space travel imposes significant gravitational and radiation stress on both cellular and systemic physiology, resulting in myriad cardiovascular changes that have not been fully characterized.
METHODS
We conducted a systematic review of the cellular and clinical adaptations of the cardiovascular system after exposure to real or simulated space travel in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed and Cochrane databases were searched in June 2021 for all peer-reviewed articles published since 1950 related to the following search terms entered in separate pairs: "cardiology and space" and "cardiology and astronaut." Only cellular and clinical studies in English concerning the investigation of cardiology and space were included.
RESULTS
Eighteen studies were identified, comprising 14 clinical and 4 cellular investigations. On the genetic level, pluripotent stem cells in humans and cardiomyocytes in mice displayed increased beat irregularity, with clinical studies revealing a persistent increase in heart rate after space travel. Further cardiovascular adaptations included a higher frequency of orthostatic tachycardia but no evidence of orthostatic hypotension, after return to sea level. Hemoglobin concentration was also consistently decreased after return to Earth. No consistent change in systolic or diastolic blood pressure or any clinically significant arrhythmias were observed during or after space travel.
CONCLUSION
Changes in oxygen carrying capacity, blood pressure, and post-flight orthostatic tachycardia may serve as reasons to further screen for pre-existing anemic and hypotensive conditions among astronauts.
Topics: Humans; Animals; Mice; Space Flight; Astronauts; Heart; Blood Pressure; Tachycardia
PubMed: 37302388
DOI: 10.1159/000531466 -
JAMA Network Open Apr 2024The associations of sodium glucose cotransporter-2 inhibitors (SGLT2is) with reduction in mortality and hospitalization rates in patients with heart failure (HF) are... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
The associations of sodium glucose cotransporter-2 inhibitors (SGLT2is) with reduction in mortality and hospitalization rates in patients with heart failure (HF) are well established. However, their association with improving functional capacity and quality of life (QOL) has been variably studied and less reported.
OBJECTIVE
To provide evidence on the extent to which SGLT2is are associated with improvement on objective measures of functional capacity and QOL in patients living with HF.
DATA SOURCES
The MEDLINE, EMBASE, and Cochrane databases were systematically searched for relevant articles on July 31, 2023.
STUDY SELECTION
Randomized, placebo-controlled clinical trials reporting the effect of SGLT2i on functional outcomes of exercise capacity (peak oxygen consumption [peak VO2] or 6-minute walk distance [6MWD]) and/or QOL using validated questionnaires for patients with HF were included.
DATA EXTRACTION AND SYNTHESIS
Data were extracted by 2 authors following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines, and a meta-analysis using the restricted maximum likelihood random-effects model was conducted.
MAIN OUTCOMES AND MEASURES
Outcomes of interest included changes in peak VO2, 6MWD, and Kansas City Cardiomyopathy Questionnaire-12 total symptom score (KCCQ-TSS), clinical summary score (KCCQ-CSS), and overall summary score (KCCQ-OSS).
RESULTS
In this meta-analysis of 17 studies, 23 523 patients (mean [range] age, 69 [60-75] years) were followed over a period ranging from 12 to 52 weeks. Four studies included peak VO2 as an outcome, 7 studies included 6MWD, and 10 studies reported KCCQ scores. Mean (SD) left ventricular ejection fraction was 43.5% (12.4%). Compared with controls, patients receiving SGLT2i treatment experienced significant increases in peak VO2 (mean difference [MD], 1.61 mL/kg/min; 95% CI, 0.59-2.63 mL/kg/min; P = .002) and 6MWD (MD, 13.09 m; 95% CI, 1.20-24.97 m; P = .03). SGLT2i use was associated with increased KCCQ-TSS (MD, 2.28 points; 95% CI, 1.74-2.81 points; P < .001), KCCQ-CSS (MD, 2.14 points; 95% CI, 1.53-2.74 points; P < .001), and KCCQ-OSS (MD, 1.90 points; 95% CI, 1.41-2.39 points; P < .001) scores. Subgroup analysis and meta-regression demonstrated almost all improvements were consistent across ejection fraction, sex, and the presence of diabetes.
CONCLUSIONS AND RELEVANCE
These findings suggest that in addition to known clinical associations with mortality and hospitalization outcomes, SGLT2i use is associated with improvement in outcomes of interest to patients' everyday lives as measured by objective assessments of maximal exercise capacity and validated QOL questionnaires, regardless of sex or ejection fraction.
Topics: Aged; Humans; Heart Failure; Quality of Life; Sodium-Glucose Transporter 2 Inhibitors; Stroke Volume; Ventricular Function, Left; Middle Aged
PubMed: 38573633
DOI: 10.1001/jamanetworkopen.2024.5135 -
Nature and Science of Sleep 2021Obstructive sleep apnea (OSA) is a highly prevalent disease with substantial public health burden. In most of the cases, there is a genetic predisposition to OSA.... (Review)
Review
Polymorphism of the Serotonin Transporter Gene and the Peripheral 5-Hydroxytryptamine in Obstructive Sleep Apnea: What Do We Know and What are We Looking for? A Systematic Review of the Literature.
BACKGROUND
Obstructive sleep apnea (OSA) is a highly prevalent disease with substantial public health burden. In most of the cases, there is a genetic predisposition to OSA. Serotonin/T-HydroxyTriptamine (5-HT) plays a key role in ventilatory stimulation, while the polymorphism of the serotonin transporter gene (STG) leads to alterations in serotonin level, making it important in OSA.
OBJECTIVE
To examine whether the 5-HydroxyTriptamine and the genetic predisposition influence the incidence and evolution of OSA, we reviewed randomized, controlled trials and observational studies on the selected topic. The secondary objective was to determine the metabolic effects of the circulating serotonin in other tissues (liver, pancreas, gut, brown adipose tissue, and white adipose tissue) and its role in the development of obesity.
DATA SOURCES
A systematic review of English articles was performed based on PubMed and the Cochrane Library databases. Search filters included randomized controlled trial, controlled clinical trial, random allocation, double-blind method, and case-control studies and used the following keywords: Brain Serotonin OR Serotonin Transporter Gene Polymorphism OR Peripheral 5-HydroxyTryptamine AND Obstructive Sleep Apnea OR Sleep Disorder Breathing OR brain serotonin AND OSA OR serotonin transporter gene OR Peripheral 5-Hydroxytryptamine AND Sleep.
STUDY ELIGIBILITY CRITERIA
The inclusion criteria for the current review were previous diagnosis of OSA, age above 18 years, and articles including quantitative data about serotonin transporter gene or peripheral serotonin. Language and time criteria were added - English articles published in the last 15 years. Studies that were not included were reviews and case reports.
STUDY APPRAISAL AND SYNTHESIS METHODS
In order to study the serotonin function, a literature research was conducted in the databases Pubmed and Cochrane Library. The following search terms were used: serotonin, 5-hydroxytryptamine, serotonin transporter gene. A critical appraisal of the included studies was performed with the Newcastle-Ottawa scale (NOS) and Delphi list.
RESULTS
The search yielded 1210 articles, from which 43 were included. The included studies suggest that the two polymorphisms of serotonin transporter gene (5HTT) - variable number of tandem repeats (VNTR) and linked polymorphic region (LPR) - are strong candidates in the pathogenesis of OSA. The allele 10 of 5HTTVNTR and the long/long (L/L) allele genotype were associated with a higher prevalence of OSA and the L allele with a higher apnea-hypopnea index and a longer time during sleep with oxygen desaturation.
LIMITATIONS
The main limitation of the present study consists of heterogeneity of the information. Being a less studied subject, randomized trials are not widely available and most data were obtained from case-control trials. Moreover, the included material indirectly approached the subject by demonstrating the effects of serotoninergic system over the metabolism, the connection between serotonin and obesity, factors which are implied in the pathogenesis of OSA.
CONCLUSION AND IMPLICATIONS OF KEY FINDINGS
The two polymorphisms of serotonin gene can be considered important factors in the diagnosis and management of OSA.
PubMed: 33603523
DOI: 10.2147/NSS.S278170 -
Journal of Toxicology 2020Iron is an essential element and the most abundant trace metal in the body involved in oxygen transport and oxygen sensing, electron transfer, energy metabolism, and DNA... (Review)
Review
Iron is an essential element and the most abundant trace metal in the body involved in oxygen transport and oxygen sensing, electron transfer, energy metabolism, and DNA synthesis. Excess labile and unchelated iron can catalyze the formation of tissue-damaging radicals and induce oxidative stress. English abstracts were identified in PubMed and Google Scholar using multiple and various search terms based on defined inclusion and exclusion criteria. Full-length articles were selected for systematic review, and secondary and tertiary references were developed. Although bloodletting or phlebotomy remains the gold standard in the management of iron overload, this systematic review is an updated account of the pitfalls of phlebotomy and classical synthetic chelators with scientific justification for the use of natural iron chelators of dietary origin in resource-poor nations.
PubMed: 32399029
DOI: 10.1155/2020/4084538 -
The Science of the Total Environment Jan 2024Low- and middle-income countries (LMIC) are disproportionately affected by air pollution and its health burden, representing a global inequity. The COVID-19 pandemic... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Low- and middle-income countries (LMIC) are disproportionately affected by air pollution and its health burden, representing a global inequity. The COVID-19 pandemic provided a unique opportunity to investigate the impact of unprecedented lockdown measures on air pollutant concentrations globally. We aim to quantify air pollutant concentration changes across LMIC settings as a result of COVID-19 restrictions.
METHODS
Searches for this systematic review and meta-analysis were carried out across five databases on 30th March 2022; MEDLINE, Embase, Web of Science, Scopus and Transport Research Information Documentation. Modelling and observational studies were included, as long as the estimates reflected city or town level data and were taken exclusively in pre-lockdown and lockdown periods. Mean percentage changes per pollutant were calculated and meta-analyses were carried out to calculate mean difference in measured ground-level observed concentrations for each pollutant (PROSPERO CRD42022326924).
FINDINGS
Of the 2982 manuscripts from initial searches, 256 manuscripts were included providing 3818 percentage changes of all pollutants. No studies included any countries from Sub-Saharan Africa and 34 % and 39.4 % of studies were from China and India, respectively. There was a mean percentage change of -37.4 %, -21.7 %, -54.6 %, -39.1 %, -48.9 %, 16.9 %, -34.9 %, -30.6 % and - 14.7 % for black carbon (BC), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO), oxides of nitrogen (NO), ozone (O), particulate matter 10 (PM) and 2.5 (PM) and sulphur dioxide (SO), respectively. Meta-analysis included 100 manuscripts, providing 908 mean concentration differences, which showed significant reduction in mean concentration in all study settings for BC (-0.46 μg/m, PI -0.85; -0.08), CO (-0.25 mg/m, PI -0.44; -0.03), NO (-19.41 μg/m, PI -31.14; -7.68) and NO (-22.32 μg/m, PI -40.94; -3.70).
INTERPRETATION
The findings of this systematic review and meta-analysis quantify and confirm the trends reported across the globe in air pollutant concentration, including increases in O. Despite the majority of global urban growth occurring in LMIC, there are distinct geographical gaps in air pollution data and, where it is available, differing approaches to analysis and reporting.
Topics: Humans; Developing Countries; Nitrogen Dioxide; Pandemics; COVID-19; Communicable Disease Control; Air Pollution; Air Pollutants; Particulate Matter; Ozone; Nitric Oxide
PubMed: 37884141
DOI: 10.1016/j.scitotenv.2023.168110 -
Journal of Translational Medicine Sep 2020Since the 1990s, neuroimaging has been utilised to study Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a debilitating illness with unknown aetiology.... (Review)
Review
BACKGROUND
Since the 1990s, neuroimaging has been utilised to study Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a debilitating illness with unknown aetiology. While brain abnormalities in ME/CFS have been identified, relatively little is known regarding which specific abnormalities are consistently observed across research groups and to what extent the observed abnormalities are reproducible.
METHOD
To identify consistent and inconsistent neuroimaging observations in ME/CFS, this retrospective and systematic review searched for studies in which neuroimaging was used to investigate brain abnormalities in ME/CFS in Ovid MEDLINE, PubMed (NCBI), and Scopus from January 1988 to July 2018. A qualitative synthesis of observations was performed to identify brain abnormalities that were consistently and inconsistently reported.
RESULTS
63 full-text articles were included in the synthesis of results from 291 identified papers. Additional brain area recruitment for cognitive tasks and abnormalities in the brain stem are frequent observations in 11 and 9 studies using different modalities from different research teams respectively. Also, sluggish blood oxygenation level-dependent (BOLD) signal responses to tasks, reduced serotonin transporters, and regional hypometabolism are consistent observations by more than two research teams. Single observations include abnormal brain tissue properties, regional metabolic abnormalities, and association of brain measures with ME/CFS symptoms. Reduced resting cerebral blood flow and volumetric brain changes are inconsistent observations across different studies.
CONCLUSION
Neuroimaging studies of ME/CFS have frequently observed additional brain area recruitment during cognitive tasks and abnormalities in the brain stem. The frequent observation of additional brain area recruitment and consistent observation of sluggish fMRI signal response suggest abnormal neurovascular coupling in ME/CFS.
Topics: Brain; Fatigue Syndrome, Chronic; Humans; Magnetic Resonance Imaging; Neuroimaging; Retrospective Studies
PubMed: 32873297
DOI: 10.1186/s12967-020-02506-6 -
Antioxidants (Basel, Switzerland) Feb 2022Mitochondrial uncoupling proteins (UCP) 1-3 fulfill many physiological functions, ranging from non-shivering thermogenesis (UCP1) to glucose-stimulated insulin release... (Review)
Review
Mitochondrial uncoupling proteins (UCP) 1-3 fulfill many physiological functions, ranging from non-shivering thermogenesis (UCP1) to glucose-stimulated insulin release (GSIS) and satiety signaling (UCP2) and muscle fuel metabolism (UCP3). Several studies have suggested that UCPs mediate these functions by facilitating proton return to the matrix. This would decrease protonic backpressure on the respiratory chain, lowering the production of hydrogen peroxide (HO), a second messenger. However, controlling mitochondrial HO production to prevent oxidative stress by activating these leaks through these proteins is still enthusiastically debated. This is due to compelling evidence that UCP2/3 fulfill other function(s) and the inability to reproduce findings that UCP1-3 use inducible leaks to control reactive oxygen species (ROS) production. Further, other studies have found that UCP2/3 may serve as Ca. Therefore, we performed a systematic review aiming to summarize the results collected on the topic. A literature search using a list of curated keywords in Pubmed, BIOSIS Citation Index and Scopus was conducted. Potentially relevant references were screened, duplicate references eliminated, and then literature titles and abstracts were evaluated using Rayyan software. A total of 1101 eligible studies were identified for the review. From this total, 416 studies were evaluated based on our inclusion criteria. In general, most studies identified a role for UCPs in preventing oxidative stress, and in some cases, this may be related to the induction of leaks and lowering protonic backpressure on the respiratory chain. However, some studies also generated evidence that UCP2/3 may mitigate oxidative stress by transporting Ca into the matrix, exporting lipid hydroperoxides, or by transporting C-4 metabolites. Additionally, some showed that activating UCP1 or 3 can increase mitochondrial ROS production, even though there is still augmented protection from oxidative stress. : Overall, most available studies demonstrate that UCPs, particularly UCP2/3, prevent oxidative stress. However, the mechanism utilized to do so remains elusive and raises the question that UCP2/3 should be renamed, since they may still not be true "uncoupling proteins".
PubMed: 35204205
DOI: 10.3390/antiox11020322 -
Sports Medicine - Open Sep 2019There is abundant and mounting information related to the molecular and biological structure and function of the Aquaporin-1 (AQP1) gene and the AQP1-Aquaporin channel.... (Review)
Review
BACKGROUND
There is abundant and mounting information related to the molecular and biological structure and function of the Aquaporin-1 (AQP1) gene and the AQP1-Aquaporin channel. Regulation of water flow across cell membranes is essential for supporting inter- and intracellular fluid balance, which is critical for health and exercise performance. The transmembrane water channel AQP1 is important for cardiorespiratory endurance (CE) because it influences fluid transfers in erythrocytes, endothelial, and pulmonary cells and is vital for transport of ammonium, bicarbonate, carbon dioxide, glycerol, nitric oxide, potassium ion, water, and trans-epithelial and renal water. Very recent publications suggest the association between a DNA sequence variant, rs1049305 (C > G), in the 3'-untranslated region of the AQP1 gene and CE performance. Other reports indicate further significant associations between AQP1 channel and CE phenotypes. The purposes of this systematic review were to examine the extent of the associations between the AQP1 rs1049305 genotype and CE exercise performance and body fluid loss in long-distance runners and AQP1 channel associations with other CE phenotypes.
METHODS
Data sources: A comprehensive review was conducted using PubMed, EMBASE, CINAHL, and Cochrane electronic databases. The search ranged from January 1, 1988, to December 31, 2018. Studies reported in English, French, and Spanish were considered. Eligibility criteria: The criteria for inclusion in the review were (a) case-control study; (b) unequivocal definition of cases and controls; (c) CE was defined as performance in endurance events, laboratory tests, and/or maximal oxygen consumption; (d) exclusion criteria of known causes; (e) genotyping performed by PCR or sequencing; (f) genotype frequencies reported; and (g) no deviation of genotype frequencies from Hardy-Weinberg equilibrium in the control group. Study appraisal: The systematic review included studies examining the AQP1 gene and AQP1 channel structure and function, associations between the AQP1 gene sequence variant rs1049305 (C > G) and CE performance, body fluid loss in long-distance runners, and other studies reporting on the AQP1 gene and channel CE phenotype associations. Synthesis methods: For each selected study, the following data were extracted: authors, year of publication, sample size and number of cases and controls, CE definition, exclusion criteria, inclusion criteria for cases and controls, methods used for genotyping, genotype, allele frequencies and HWE for genotype frequencies in cases and control groups, and method of AQP1 gene and AQP1 channel analysis.
RESULTS
The initial databases search found 172 pertinent studies. Of those, 46 studies were utilized in the final synthesis of the systematic review. The most relevant findings were (a) the identification of an independent replication of the association between AQP1 gene sequence variant rs1049305 (C > G) and CE performance; (b) the association of the rs1049305 C-allele with faster CE running performance; (c) in knockout model, using a linear regression analysis of distance run as a function of Aqp1 status (Aqp1-null vs. wild-type mice) and conditions of hypoxia (ambient [O] = 16%), normoxia (21%), and hyperoxia (40%) indicated that the Aqp1 knockout ran less distance than the wild-type mice (p < 0.001); (d) in vitro, a reduced AQP1 expression was associated with the presence of the rs1049305 G-allele; (e) AQP1 null humans led normal lives and were entirely unaware of any physical limitations. However, they could not support fluid homeostasis when exposed to chronic fluid overload. The limited number of studies with "adequate sample sizes" in various racial and ethnic groups precluding to perform proper in-depth statistical analysis.
CONCLUSIONS
The AQP1 gene and AQP1 channel seems to support homeostatic mechanisms, yet to be totally understood, that are auxiliary in achieving an advantage during endurance exercise. AQP1 functions are vital during exercise and have a profound influence on endurance running performance. AQP1s are underappreciated structures that play vital roles in cellular homeostasis at rest and during CE endurance running exercise. The outcome of the present systematic review provide support to the statement of hypotheses and further research endeavors on the likely influence of AQP1 gene and AQP1 channel on CE performance. Registration: The protocol is not registered.
PubMed: 31486928
DOI: 10.1186/s40798-019-0213-0 -
Medicina (Kaunas, Lithuania) May 2023: Colchicine has been proposed as a cytokine storm-blocking agent for COVID-19 due to its efficacy as an anti-inflammatory drug. The findings of the studies were... (Review)
Review
: Colchicine has been proposed as a cytokine storm-blocking agent for COVID-19 due to its efficacy as an anti-inflammatory drug. The findings of the studies were contentious on the role of colchicine in preventing deterioration in COVID-19 patients. We aimed to evaluate the efficacy of colchicine in COVID-19-hospitalized patients. : A retrospective observational cohort study was carried out at three major isolation hospitals in Alexandria (Egypt), covering multiple centers. In addition, a systematic review was conducted by searching six different databases for published studies on the utilization of colchicine in patients with COVID-19 until March 2023. The primary outcome measure was to determine whether colchicine could decrease the number of days that the patient needed supplemental oxygen. The secondary outcomes were to evaluate whether colchicine could reduce the number of hospitalization days and mortality rate in these patients. : Out of 515 hospitalized COVID-19 patients, 411 were included in the survival analysis. After adjusting for the patients' characteristics, patients not receiving colchicine had a shorter length of stay (median: 7.0 vs. 6.0 days) and fewer days of supplemental oxygen treatment (median: 6.0 vs. 5.0 days), < 0.05, but there was no significant difference in mortality rate. In a subgroup analysis based on oxygen equipment at admission, patients admitted on nasal cannula/face masks who did not receive colchicine had a shorter duration on oxygen supply than those who did [Hazard Ratio (HR) = 0.76 (CI 0.59-0.97)]. Using cox-regression analysis, clarithromycin compared to azithromycin in colchicine-treated patients was associated with a higher risk of longer duration on oxygen supply [HR = 1.77 (CI 1.04-2.99)]. Furthermore, we summarized 36 published colchicine studies, including 114,878 COVID-19 patients. COVID-19-hospitalized patients who were given colchicine had poorer outcomes in terms of the duration of supplemental oxygen use and the length of their hospital stay. Therefore, based on these findings, the use of colchicine is not recommended for COVID-19-hospitalized adults.
Topics: Adult; Humans; COVID-19; Colchicine; Retrospective Studies; SARS-CoV-2; Oxygen Saturation; Oxygen; Observational Studies as Topic
PubMed: 37241167
DOI: 10.3390/medicina59050934