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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 -
3 Biotech Oct 2023Drought stress remains one of the most detrimental environmental constraints that hampers plant growth and development resulting in reduced yield and leading to economic... (Review)
Review
Drought stress remains one of the most detrimental environmental constraints that hampers plant growth and development resulting in reduced yield and leading to economic losses. Studies have highlighted the beneficial role of carbon-based nanomaterials (NMs) such as multiwalled carbon nanotubes (MWNTs), single-walled carbon nanotubes (SWNTs), graphene, fullerene, and metal-based nanoparticles (NPs) (Ag, Au, Cu, FeO, TiO, and ZnO) in plants under unfavorable conditions such as drought. NPs help plants cope with drought by improving plant growth indices and enhancing biomass. It improves water and nutrient uptake and utilization. It helps retain water by altering the cell walls and regulating stomatal closure. The photosynthetic parameters in NP-treated plants reportedly improved with the increase in pigment content and rate of photosynthesis. Due to NP exposure, the activation of enzymatic and nonenzymatic antioxidants has reportedly improved. These antioxidants play a significant role in the defense system against stress. Studies have reported the accumulation of osmolytes and secondary metabolites. Osmolytes scavenge reactive oxygen species, which can cause oxidative stress in plants. Secondary metabolites are involved in the water retention process, thus improving plant coping strategies with stress. The deleterious effects of drought stress are alleviated by reducing malondialdehyde resulting from lipid peroxidation. Reactive oxygen species accumulation is also controlled with NP treatment. Furthermore, NPs have been reported to regulate the expression of drought-responsive genes and the biosynthesis of phytohormones such as abscisic acid, auxin, gibberellin, and cytokinin, which help plants defend against drought stress. This study reviewed 72 journal articles from 192 Google Scholar, ScienceDirect, and PubMed papers. In this review, we have discussed the impact of NP treatment on morphological, physio-biochemical, and molecular responses in monocot and dicot plants under drought conditions with an emphasis on NP uptake, transportation, and localization.
PubMed: 37693636
DOI: 10.1007/s13205-023-03751-4 -
Journal of Applied Physiology... Jun 2024This systematic review and meta-analysis examined the physiological mechanisms responsible for lower peak exercise leg oxygen uptake (V̇o) in patients with chronic... (Meta-Analysis)
Meta-Analysis Review
This systematic review and meta-analysis examined the physiological mechanisms responsible for lower peak exercise leg oxygen uptake (V̇o) in patients with chronic disease. Studies measuring peak leg V̇o (primary outcome) and its physiological determinants during large (cycle) or small muscle mass exercise (single-leg knee extension, SLKE) in patients with chronic disease were included in this meta-analysis. Pooled estimates for each outcome were reported as a weighted mean difference (WMD) between chronic disease and controls. We included 10 studies that measured peak leg V̇o in patients with chronic disease ( = 109, mean age: 45 yr; encompassing chronic obstructive pulmonary disease, COPD, heart failure with reduced ejection fraction, HFrEF, or chronic renal failure, RF) and age-matched controls ( = 88). In pooled analysis, peak leg V̇o (WMD; -0.23 L/min, 95% CI: -0.32 to -0.13), leg oxygen (O) delivery (WMD: -0.27 L/min, 95% CI: -0.37 to -0.17), and muscle O diffusive conductance (WMD: -5.2 mL/min/mmHg, 95% CI: -7.1 to -3.2) were all significantly lower during cycle and SLKE exercise in chronic disease versus controls. These results highlight that during large and small muscle mass exercise in patients with COPD, HFrEF, or RF, there is no single factor causing peak V̇o limitations. Specifically, the lower peak V̇o in these pathologies is due to not only the expected impairments in convective O delivery but also impairments in muscle oxygen diffusive transport from capillary to mitochondria. Whether impaired muscle O transport is caused solely by inactivity or additional muscle pathology remains in question. Peripheral (skeletal muscle and vasculature) factors contribute significantly to reduced exercise capacity during both large and small muscle mass exercise in chronic diseases such as COPD, HFrEF, or RF and should be important targets of therapy in addition to the primary organs (lungs, heart, and kidneys) affected by disease.
Topics: Humans; Oxygen Consumption; Leg; Muscle, Skeletal; Chronic Disease; Exercise; Pulmonary Disease, Chronic Obstructive; Oxygen; Heart Failure
PubMed: 38482572
DOI: 10.1152/japplphysiol.00918.2023 -
Environmental Research Jan 2023Volatile organic compound (VOC) emissions have attracted wide attention due to their impacts on atmospheric quality and public health. However, most studies reviewed... (Review)
Review
Volatile organic compound (VOC) emissions have attracted wide attention due to their impacts on atmospheric quality and public health. However, most studies reviewed certain aspects of natural VOCs (NVOCs) or anthropogenic VOCs (AVOCs) rather than comprehensively quantifying the hotspots and evolution trends of AVOCs and NVOCs. We combined the bibliometric method with the evolution tree and Markov chain to identify research focus and uncover the trends in VOC emission sources. This study found that research mainly focused on VOC emission characteristics, effects on air quality and health, and VOC emissions under climate change. More studies concerned on AVOCs than on NVOCs, and AVOC emissions have shifted with a decreasing proportion of transport emissions and an increasing share of solvent utilization in countries with high emissions and publications (China and the USA). Research on AVOCs is imperative to develop efficient and economical abatement techniques specific to solvent sources or BTEX species to mitigate the detrimental effects. Research on NVOCs originating from human sources risen due to their application in medicine, while studies on sources sensitive to climate change grew slowly, including plants, biomass burning, microbes, soil and oceans. Research on the long-term responses of NVOCs derived from various sources to climate warming is warranted to explore the evolution of emissions and the feedback on global climate. It is worthwhile to establish an emission inventory with all kinds of sources, accurate estimation, high spatial and temporal resolution to capture the emission trends in the synergy of industrialization and climate change as well as to simulate the effects on air quality. We review VOC emissions from both anthropogenic and natural sources under climate change and their effects on atmospheric quality and health to point out the research directions for the comprehensive control of global VOCs and mitigation of O pollution.
Topics: Humans; Volatile Organic Compounds; Air Pollutants; Ozone; Air Pollution; Solvents; China; Environmental Monitoring
PubMed: 36162470
DOI: 10.1016/j.envres.2022.114386 -
Current Problems in Cardiology Feb 2023Transient receptor potential (TRP) family play critical roles in cardiovascular system. TRPM family as largest TRP subfamily is non-voltage Ca2+-activated selective... (Review)
Review
Transient receptor potential (TRP) family play critical roles in cardiovascular system. TRPM family as largest TRP subfamily is non-voltage Ca2+-activated selective channels which has 8 members. This study aimed to discuss the role of TRPM family in cardiovascular system and diseases. Systematic search was performed covering PubMed, ISI Web of Science, and Google Scholar from inception until June 2021 using related keywords and Mesh terms for English studies with human, animal and in-vitro subjects. Finally 10 studies were selected for data extraction. Reviewing the articles showed that TRPM2, TRPM4, TRPM5, TRPM6 and TRPM7 play important roles in cardiovascular system and diseases. TRPM2 could be activated by reactive oxygen species (ROS) and effects on cardiac injury and cardiac fibrosis. TRPM7 and TRPM6 also have been reported to be associated with cardiac fibrosis and atrial fibrosis development respectively. TRPM4 channels contributed to resting membrane potential of cerebral artery smooth muscle cells and atrial contraction. TRPM5 channels are bitter taste sensors and prevent high salt intake and consequently high blood pressure due to the high salt intake. In conclusion based on the proof of the effectiveness of some members of TRPM family in the cardiovascular system, research on other members of this channel group seems to be useful and necessary to find their possible connection to the cardiovascular system.
Topics: Animals; Humans; TRPM Cation Channels; Sodium Chloride, Dietary; Membrane Potentials; Clusterin; Cardiovascular System; Protein Serine-Threonine Kinases
PubMed: 34644560
DOI: 10.1016/j.cpcardiol.2021.101012 -
Pharmaceuticals (Basel, Switzerland) May 2020Epilepsy is a serious neurological disorder affecting around 70 million people globally and is characterized by spontaneous recurrent seizures. Recent evidence indicates... (Review)
Review
Epilepsy is a serious neurological disorder affecting around 70 million people globally and is characterized by spontaneous recurrent seizures. Recent evidence indicates that dysfunction in metabolic processes can lead to the alteration of neuronal and network excitability, thereby contributing to epileptogenesis. Developing a suitable animal model that can recapitulate all the clinical phenotypes of human metabolic epilepsy (ME) is crucial yet challenging. The specific environment of many symptoms as well as the primary state of the applicable neurobiology, genetics, and lack of valid biomarkers/diagnostic tests are the key factors that hinder the process of developing a suitable animal model. The present systematic review summarizes the current state of available animal models of metabolic dysfunction associated with epileptic disorders. A systematic search was performed by using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) model. A range of electronic databases, including google scholar, Springer, PubMed, ScienceDirect, and Scopus, were scanned between January 2000 and April 2020. Based on the selection criteria, 23 eligible articles were chosen and are discussed in the current review. Critical analysis of the selected literature delineated several available approaches that have been modeled into metabolic epilepsy and pointed out several drawbacks associated with the currently available models. The result describes available models of metabolic dysfunction associated with epileptic disorder, such as mitochondrial respiration deficits, Lafora disease (LD) model-altered glycogen metabolism, causing epilepsy, glucose transporter 1 (GLUT1) deficiency, adiponectin responsive seizures, phospholipid dysfunction, glutaric aciduria, mitochondrial disorders, pyruvate dehydrogenase (PDH) α-subunit gene (PDHA1), pyridoxine dependent epilepsy (PDE), BCL2-associated agonist of cell death (BAD), Kcna1 knock out (KO), and long noncoding RNAs (lncRNA) cancer susceptibility candidate 2 (lncRNA CASC2). Finally, the review highlights certain focus areas that may increase the possibilities of developing more suitable animal models and underscores the importance of the rationalization of animal models and evaluation methods for studying ME. The review also suggests the pressing need of developing precise robust animal models and evaluation methods for investigating ME.
PubMed: 32466498
DOI: 10.3390/ph13060106 -
International Journal of Molecular... Mar 2023Energy production by cancer is driven by accelerated glycolysis, independently of oxygen levels, which results in increased lactate production. Lactate is shuttled to... (Review)
Review
Energy production by cancer is driven by accelerated glycolysis, independently of oxygen levels, which results in increased lactate production. Lactate is shuttled to and from cancer cells via monocarboxylate transporters (MCTs). MCT1 works both as an importer and an extruder of lactate, being widely studied in recent years and generally associated with a cancer aggressiveness phenotype. The aim of this systematic review was to assess the prognostic value of MCT1 immunoexpression in different malignancies. Study collection was performed by searching nine different databases (PubMed, EMBASE, ScienceDirect, Scopus, Cochrane Library, Web of Science, OVID, TRIP and PsycINFO), using the keywords "cancer", "Monocarboxylate transporter 1", "SLC16A1" and "prognosis". Results showed that MCT1 is an indicator of poor prognosis and decreased survival for cancer patients in sixteen types of malignancies; associations between the transporter's overexpression and larger tumour sizes, higher disease stage/grade and metastasis occurrence were also frequently observed. Yet, MCT1 overexpression correlated with better outcomes in colorectal cancer, pancreatic ductal adenocarcinoma and non-small cell lung cancer patients. These results support the applicability of MCT1 as a biomarker of prognosis, although larger cohorts would be necessary to validate the overall role of MCT1 as an outcome predictor.
Topics: Humans; Carcinoma, Non-Small-Cell Lung; Lactic Acid; Lung Neoplasms; Monocarboxylic Acid Transporters; Pancreatic Neoplasms; Prognosis; Symporters
PubMed: 36982217
DOI: 10.3390/ijms24065141 -
Journal of Applied Physiology... Feb 2022Pulmonary gas exchange during diving or in a dry hyperbaric environment is affected by increased breathing gas density and possibly water immersion. During free diving,... (Review)
Review
Pulmonary gas exchange during diving or in a dry hyperbaric environment is affected by increased breathing gas density and possibly water immersion. During free diving, there is also the effect of apnea. Few studies have published blood gas data in underwater or hyperbaric environments: this review summarizes the available literature and was used to test the hypothesis that arterial Po under hyperbaric conditions can be predicted from blood gas measurement at 1 atmosphere assuming a constant arterial/alveolar Po ratio (a:A). A systematic search was performed on traditional sources including arterial blood gases obtained on humans in hyperbaric or underwater environments. The a:A was calculated at 1 atmosphere absolute (ATA). For each condition, predicted arterial partial pressure of oxygen ([Formula: see text]) at pressure was calculated using the 1 ATA a:A, and the measured [Formula: see text] was plotted against the predicted value with Spearman correlation coefficients. Of 3,640 records reviewed, 30 studies were included: 25 were reports describing values obtained in hyperbaric chambers, and the remaining were collected while underwater. Increased inspired O at pressure resulted in increased [Formula: see text], although underlying lung disease in patients treated with hyperbaric oxygen attenuated the rise. [Formula: see text] generally increased only slightly. In breath-hold divers, hyperoxemia generally occurred at maximum depth, with hypoxemia after surfacing. The a:A adequately predicted the [Formula: see text] under various conditions: dry ( = 0.993, < 0.0001), rest versus exercise ( = 0.999, < 0.0001), and breathing mixtures ( = 0.995, < 0.0001). In conclusion, pulmonary oxygenation under hyperbaric conditions can be reliably and accurately predicted from 1 ATA a:A measurements.
Topics: Blood Gas Analysis; Diving; Humans; Hyperbaric Oxygenation; Oxygen; Partial Pressure; Pulmonary Gas Exchange
PubMed: 34941439
DOI: 10.1152/japplphysiol.00569.2021 -
The Laryngoscope Jun 2020The inner ear is responsible for hearing and balance and consists of a membranous labyrinth within a bony labyrinth. The balance structure is divided into the otolith...
The inner ear is responsible for hearing and balance and consists of a membranous labyrinth within a bony labyrinth. The balance structure is divided into the otolith organ that recognizes linear acceleration and the semicircular canal that is responsible for rotational movement. The cochlea is the hearing organ. The external and middle ear are covered with skin and mucosa, respectively, and the space is filled with air, whereas the inner ear is composed of endolymph and perilymph. The inner ear is a fluid-filled sensory organ composed of hair cells with cilia on the upper part of the cells that convert changes in sound energy and balance into electric energy through the hair cells to transmit signals to the auditory nerve through synapses. Aquaporins (AQPs) are a family of transmembrane proteins present in all species that can be roughly divided into three subfamilies according to structure and function: 1) classical AQP, 2) aquaglyceroporin, and 3) superaquaporin. Currently, the subfamily of mammalian species is known to include 13 AQP members (AQP0-AQP12). AQPs have a variety of functions depending on their structure and are related to inner ear diseases such as Meniere's disease, sensorineural hearing loss, and presbycusis. Additional studies on the relationship between the inner ear and AQPs may be helpful in the diagnosis and treatment of inner ear disease. Laryngoscope, 130:1532-1539, 2020.
Topics: Animals; Aquaporins; Humans; Labyrinth Diseases
PubMed: 31593306
DOI: 10.1002/lary.28334