High-Carbohydrate Diet Enhanced the Anticontractile Effect of Perivascular Adipose Tissue Through Activation of Renin-Angiotensin System
The perivascular adipose tissue (PVAT) is an active endocrine organ responsible for release several substances that influence on vascular tone. Increasing evidence suggest that hyperactivation of the local renin-angiotensin system (RAS) in the PVAT plays a pivotal role in the pathogenesis of cardiometabolic diseases. However, the local RAS contribution to the PVAT control of vascular tone during obesity is still not clear. Since the consumption of a high-carbohydrate diet (HC diet) contributes to obesity inducing a rapid and sustained increase in adiposity, so that the functional activity of PVAT could be modulated, we aim...
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

A New Detection Method Defining the Aerobic Threshold for Endurance Exercise and Training Prescription Based on Fractal Correlation Properties of Heart Rate Variability
The short-term scaling exponent alpha1 of detrended fluctuation analysis (DFA a1), a nonlinear index of heart rate variability (HRV) based on fractal correlation properties, has been shown to steadily change with increasing exercise intensity. To date, no study has specifically examined using the behavior of this index as a method for defining a low intensity exercise zone. The aim of this report is to compare both oxygen intake (VO2) and heart rate (HR) reached at the first ventilatory threshold (VT1), a well-established delimiter of low intensity exercise, to those derived from a predefined DFA a1 transitional value. Gas...
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

Cerebral vs. Cardiovascular Responses to Exercise in Type 2 Diabetic Patients
The human brain is constantly active and even small limitations to cerebral blood flow (CBF) may be critical for preserving oxygen and substrate supply, e.g., during exercise and hypoxia. Exhaustive exercise evokes a competition for the supply of oxygenated blood between the brain and the working muscles, and inability to increase cardiac output sufficiently during exercise may jeopardize cerebral perfusion of relevance for diabetic patients. The challenge in diabetes care is to optimize metabolic control to slow progression of vascular disease, but likely because of a limited ability to increase cardiac output, these pati...
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

Calcium-Sensing Receptor Participates in High Glucose-Induced EndMT in Primary Human Aortic Endothelial Cells
ConclusionOur research demonstrated that HG-induced EndMT in HAECs might be mediated by CaSR and the downstream nuclear translocation of β-catenin. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

Utility of Zebrafish Models of Acquired and Inherited Long QT Syndrome
Long-QT Syndrome (LQTS) is a cardiac electrical disorder, distinguished by irregular heart rates and sudden death. Accounting for ∼40% of cases, LQTS Type 2 (LQTS2), is caused by defects in the Kv11.1 (hERG) potassium channel that is critical for cardiac repolarization. Drug block of hERG channels or dysfunctional channel variants can result in acquired or inherited LQTS2, respectively, which are typified by delayed repolarization and predisposition to lethal arrhythmia. As such, there is significant interest in clear identification of drugs and channel variants that produce clinically meaningful perturbation of hERG c...
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

Links Between Testosterone, Oestrogen, and the Growth Hormone/Insulin-Like Growth Factor Axis and Resistance Exercise Muscle Adaptations
Maintenance of skeletal muscle mass throughout the life course is key for the regulation of health, with physical activity a critical component of this, in part, due to its influence upon key hormones such as testosterone, estrogen, growth hormone (GH), and insulin-like growth factor (IGF). Despite the importance of these hormones for the regulation of skeletal muscle mass in response to different types of exercise, their interaction with the processes controlling muscle mass remain unclear. This review presents evidence on the importance of these hormones in the regulation of skeletal muscle mass and their responses, and ...
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

Slight Disruption in Intestinal Environment by Dextran Sodium Sulfate Reduces Egg Yolk Size Through Disfunction of Ovarian Follicle Growth
In conclusion, the oral administration of a lower dose of DSS is an useful method to cause slight disruptions of intestinal environment, and the intestinal condition decreases egg yolk size through disfunction of ovarian follicle. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

Serum Renin Levels Increase With Age in Boys Resulting in Higher Renin Levels in Young Men Compared to Young Women, and Soluble Angiotensin-Converting Enzyme 2 Correlates With Renin and Body Mass Index
Background: Age, sex, and body constitution may affect the shedding of membrane bound angiotensin-converting enzyme 2 (mACE2) and lead to a relative mACE2 deficiency. However, it is unclear if differences, reflected by serum renin levels, exist in the basal renin-angiotensin-system (RAS) between children and adults, boys, and girls as well as young women and young men. Furthermore, it remains to be investigated if renin and soluble ACE2 (sACE2) levels are correlated with body mass index (BMI) in children and young adults. The aim of this observational study was to assess age-and sex differences in serum renin, and the rela...
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

SARS-CoV-2 Mediated Endothelial Dysfunction: The Potential Role of Chronic Oxidative Stress
Endothelial cells have emerged as key players in SARS-CoV-2 infection and COVID-19 inflammatory pathologies. Dysfunctional endothelial cells can promote chronic inflammation and disease processes like thrombosis, atherosclerosis, and lung injury. In endothelial cells, mitochondria regulate these inflammatory pathways via redox signaling, which is primarily achieved through mitochondrial reactive oxygen species (mtROS). Excess mtROS causes oxidative stress that can initiate and exacerbate senescence, a state that promotes inflammation and chronic endothelial dysfunction. Oxidative stress can also activate feedback loops tha...
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

Post-activation Performance Enhancement in the Bench Press Throw: A Systematic Review and Meta-Analysis
Conclusion: The presented meta-analysis shows that performing a CA induces a small PAPE effect for the BPT performance in resistance-trained men. Individuals seeking to improve their BPT performance should consider preceding them with a single set of the BP exercise at moderate intensity (60–84% 1RM), performed 5–7 min before the explosive activity. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

Photobiomodulation 30 min or 6 h Prior to Cycling Does Not Alter Resting Blood Flow Velocity, Exercise-Induced Physiological Responses or Time to Exhaustion in Healthy Men
ConclusionsPBMT at 152 J applied 30 min or 6 h before cycling at severe-intensity did not alter resting plasma nitrite and blood flow velocity in the femoral artery, exercise-induced physiological responses, or time to exhaustion in healthy untrained men. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 15, 2021 Category: Physiology Source Type: research

M/M/Infinity Birth-Death Processes – A Quantitative Representational Framework to Summarize and Explain Phase Singularity and Wavelet Dynamics in Atrial Fibrillation
ConclusionM/M/∞ birth–death processes provide an accurate quantitative representational architecture to characterize PS and wavelet population dynamics in AF, by providing governing equations to understand the regeneration of PS and wavelets during sustained AF, as well as providing insight into the mechanism of spontaneous AF termination. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 14, 2021 Category: Physiology Source Type: research

Rapid Gardos Hereditary Xerocytosis Diagnosis in 8 Families Using Reticulocyte Indices
We report here that this diagnosis can be sped up using red blood cell (RBC) indices performed on an ADVIA 2120 (Siemens®) analyzer, which measures reticulocyte mean corpuscular volume (rMCV) and mean corpuscular hemoglobin concentration (rMCHC). We studied reticulocyte indices in 3 new and 12 described patients (8 families) with Gardos-HX, 11 subjects presented the recurrent p.Arg352His mutation, 4 cases (two families) carried a private KCNN4 mutation. They were compared to 79 described patients (49 families) with Piezo1-HX. Surprisingly, in Gardos-HX cases, rMCV revealed to be smaller than MCV and rMCHC higher than M...
Source: Frontiers in Physiology - January 14, 2021 Category: Physiology Source Type: research

Program of Seven 45-min Dry Immersion Sessions Improves Choice Reaction Time in Parkinson ’s Disease
The study hypothesis held that in subjects with Parkinson’s disease (PD), the reaction time (RT) tests of the higher cognition demand would have more readily improved under the program of analog microgravity (μG) modeled with “dry” immersion (DI). To test this hypothesis, 10 subjects with PD have passed through a program of seven DI sessions (each 45 min long) within 25–30 days, with overall μG dose 5 1/4 h. Five patients were enrolled as controls, without DI (noDI group). Simple RT (SRT), disjunctive RT (DRT), and choice RT (CRT) were assessed in four study points: before the DI program (preD...
Source: Frontiers in Physiology - January 14, 2021 Category: Physiology Source Type: research

Inflammation in Periodontal Disease: Possible Link to Vascular Disease
Inflammation is a well-organized protective response to pathogens and consists of immune cell recruitment into areas of infection. Inflammation either clears pathogens and gets resolved leading to tissue healing or remains predominantly unresolved triggering pathological processes in organs. Periodontal disease (PD) that is initiated by specific bacteria also triggers production of inflammatory mediators. These processes lead to loss of tissue structure and function. Reactive oxygen species and oxidative stress play a role in susceptibility to periodontal pathogenic bacterial infections. Periodontal inflammation is a risk ...
Source: Frontiers in Physiology - January 14, 2021 Category: Physiology Source Type: research

Circadian Mechanisms: Cardiac Ion Channel Remodeling and Arrhythmias
Circadian rhythms are involved in many physiological and pathological processes in different tissues, including the heart. Circadian rhythms play a critical role in adverse cardiac function with implications for heart failure and sudden cardiac death, highlighting a significant contribution of circadian mechanisms to normal sinus rhythm in health and disease. Cardiac arrhythmias are a leading cause of morbidity and mortality in patients with heart failure and likely cause ∼250,000 deaths annually in the United States alone; however, the molecular mechanisms are poorly understood. This suggests the need to improve our c...
Source: Frontiers in Physiology - January 14, 2021 Category: Physiology Source Type: research

Melatonin Lowers HIF-1 α Content in Human Proximal Tubular Cells (HK-2) Due to Preventing Its Deacetylation by Sirtuin 1
Although melatonin is widely known for its nephroprotective properties, there are no reports clearly pointing at its impact on the activity of hypoxia-inducible factor-1 (HIF-1), the main mediator of metabolic responses to hypoxia, in kidneys. The aim of the present study was to elucidate how melatonin affects the expression of the regulatory subunit HIF-1α in renal proximal tubules. HK-2 cells, immortalized human proximal tubular cells, were cultured under hypoxic conditions (1% O2). Melatonin was applied at 100 μM concentration. Protein and mRNA contents were determined by Western blot and RT-qPCR, respectively....
Source: Frontiers in Physiology - January 14, 2021 Category: Physiology Source Type: research

Quantifying Dynamical High-Order Interdependencies From the O-Information: An Application to Neural Spiking Dynamics
We address the problem of efficiently and informatively quantifying how multiplets of variables carry information about the future of the dynamical system they belong to. In particular we want to identify groups of variables carrying redundant or synergistic information, and track how the size and the composition of these multiplets changes as the collective behavior of the system evolves. In order to afford a parsimonious expansion of shared information, and at the same time control for lagged interactions and common effect, we develop a dynamical, conditioned version of the O-information, a framework recently proposed to...
Source: Frontiers in Physiology - January 14, 2021 Category: Physiology Source Type: research

Diffusion Entropy vs. Multiscale and R ényi Entropy to Detect Progression of Autonomic Neuropathy
We review the literature to argue the importance of the occurrence of crucial events in the dynamics of physiological processes. Crucial events are interpreted as short time intervals of turbulence, and the time distance between two consecutive crucial events is a waiting time distribution density with an inverse power law (IPL) index μ, with μ
Source: Frontiers in Physiology - January 14, 2021 Category: Physiology Source Type: research

Physiological Tradeoffs of Immune Response Differs by Infection Type in Pieris napi
Understanding the tradeoffs that result from successful infection responses is central to understanding how life histories evolve. Gaining such insights, however, can be challenging, as they may be pathogen specific and confounded with experimental design. Here, we investigated whether infection from gram positive or negative bacteria results in different physiological tradeoffs, and whether these infections impact life history later in life (post-diapause development), in the butterfly Pieris napi. During the first 24 h after infection (3, 6, 12, and 24 h), after removing effects due to injection, larvae infected with Mic...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

High Throughput Sequencing of MicroRNA in Rainbow Trout Plasma, Mucus, and Surrounding Water Following Acute Stress
The objective of this study was to identify the altered plasma miRNAs in response to acute stress in rainbow trout (Oncorhynchus mykiss), as well as altered miRNAs in fish epidermal mucus and the surrounding ambient water. Small RNA was extracted and sequenced from plasma, mucus, and water collected from rainbow trout pre- and 1 h-post a 3-min air stressor. Following small RNA-Seq and pathway analysis, we identified differentially expressed plasma miRNAs that targeted biosynthetic, degradation, and metabolic pathways. We successfully isolated miRNA from trout mucus and the surrounding water and detected differences in miRN...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Mild Attenuation of the Pulmonary Inflammatory Response in a Mouse Model of Hereditary Hemochromatosis Type 4
The respiratory tract is constantly exposed to pathogens that require iron for proliferation and virulence. Pulmonary iron levels are increased in several lung diseases and associated with increased susceptibility to infections. However, regulation of lung iron homeostasis and its cross talk to pulmonary immune responses are largely unexplored. Here we investigated how increased lung iron levels affect the early pulmonary inflammatory response. We induced acute local pulmonary inflammation via aerosolized LPS in a mouse model of hereditary hemochromatosis type 4 (Slc40a1C326S/C326S), which is hallmarked by systemic and pul...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Relationships Between Circulating Irisin Response to Ice Swimming and Body Composition in People With Regular Exercise Experience
Severe cold exercise involves the irisin response, and may be related to body composition. We aimed to investigate changes in circulating irisin after ice swimming (IS), as well as to evaluate the correlation between body composition and the change in irisin caused by IS (Δirisin). 81 ice swimmers were recruited to perform IS activities. Blood samples were drawn 30 min before and 30 min after IS, and the serum levels of irisin and the ice swimmers’ body composition were measured. As results, circulating irisin declined significantly during the recovery period following IS exercise (P
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Red Blood Cell Morphodynamics: A New Potential Marker in High-Risk Patients
In this study, we investigated the existence of any association between RBC morphodynamics and HRP features in individuals with different grades of coronary stenosis detected by coronary computed tomography angiography (CCTA). Ninety-one consecutive individuals who underwent CCTA [33 no CAD; 26 nonobstructive (nonob), and 32 obstructive (ob) CAD] were enrolled. RBC morphodynamic features, i.e., RBC aggregability and deformability, were analyzed by means of Laser Assisted Optical Rotation Cell Analyzer (LoRRca MaxSis). The putative global RBC morphodynamic (RMD) score and the related risk chart, associating the extent of HR...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Developmental Changes of the Ovary in Neonatal Cotton Rat (Sigmodon hispidus)
The reproductive characteristics and ovarian development in cotton rats (Sigmodon hispidus, CRs) are unclear, although CRs are commonly used as animal models in biomedical research. We previously reported that young (6–8 weeks) CRs showed multi-oocyte follicles (MOFs) and double nucleated oocytes (DNOs) in different stages of follicles. The developmental changes in neonatal CR ovaries were investigated in the present study and were compared with our findings in previous studies of unique phenotypes, particularly in oocytes. CR ovaries at postnatal days (PND) 0, 4, and 7 were obtained from the Hokkaido Institute of Pu...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Molecular Basis for the Therapeutic Effects of Exercise on Mitochondrial Defects
Mitochondrial dysfunction is common to many organ system disorders, including skeletal muscle. Aging muscle and diseases of muscle are often accompanied by defective mitochondrial ATP production. This manuscript will focus on the pre-clinical evidence supporting the use of regular exercise to improve defective mitochondrial metabolism and function in skeletal muscle, through the stimulation of mitochondrial turnover. Examples from aging muscle, muscle-specific mutations and cancer cachexia will be discussed. We will also examine the effects of exercise on the important mitochondrial regulators PGC-1α, and Parkin, and...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Evaluation of Cardiac Circadian Rhythm Deconditioning Induced by 5-to-60 Days of Head-Down Bed Rest
Head-down tilt (HDT) bed rest elicits changes in cardiac circadian rhythms, generating possible adverse health outcomes such as increased arrhythmic risk. Our aim was to study the impact of HDT duration on the circadian rhythms of heart beat (RR) and ventricular repolarization (QTend) duration intervals from 24-h Holter ECG recordings acquired in 63 subjects during six different HDT bed rest campaigns of different duration (two 5-day, two 21-day, and two 60-day). Circadian rhythms of RR and QTend intervals series were evaluated by Cosinor analysis, resulting in a value of midline (MESOR), oscillation amplitude (OA) and acr...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Protective Effect of Xinmailong Injection on Rats With Myocardial Infarction
In conclusion, Xinmailong is safe and had anti-inflammatory, heart-improving, and myocardial-protective effects. Its effectiveness is not inferior to that of sodium creatine phosphate. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

The Role of Glycocalyx and Caveolae in Vascular Homeostasis and Diseases
We describe the structure, synthesis, and function of glycocalyx and caveolae in vascular cells under physiological and pathophysiological conditions. Special focus will be given in glycocalyx and caveolae that are associated with impaired production of nitric oxide (NO) and generation of reactive oxygen species (ROS). Such alterations could contribute to the development of cardiovascular diseases, such as atherosclerosis, and hypertension. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Benefit of Physiologically Variable Over Pressure-Controlled Ventilation in a Model of Chronic Obstructive Pulmonary Disease: A Randomized Study
IntroductionThe advantages of physiologically variable ventilation (PVV) based on a spontaneous breathing pattern have been demonstrated in several respiratory conditions. However, its potential benefits in chronic obstructive pulmonary disease (COPD) have not yet been characterized. We used an experimental model of COPD to compare respiratory function outcomes after 6 h of PVV versus conventional pressure-controlled ventilation (PCV).Materials and MethodsRabbits received nebulized elastase and lipopolysaccharide throughout 4 weeks. After 30 days, animals were anesthetized, tracheotomized, and randomized to receive 6 h of ...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Antenatal Endotoxin Impairs Lung Mechanics and Increases Sensitivity to Ventilator-Induced Lung Injury in Newborn Rat Pups
Perinatal inflammation due to chorioamnionitis and ventilator-induced lung injury (VILI) at birth is independent risk factors for the development of bronchopulmonary dysplasia (BPD). We have previously shown that antenatal endotoxin (ETX) causes abnormal lung structure and function in 2-week-old rats, but whether ETX impairs lung mechanics at birth and increases risk for VILI is unknown. Fetal rats were exposed to 10 μg endotoxin or saline via intra-amniotic injection. At birth (D0) or 7 days (D7), rats received 90 min of lung protective ventilation [PROTECT group; tidal volume (Vt) = 6 ml/kg with positive end expirator...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Editorial: Saliva and Oral Microbiota: From Physiology to Diagnostic and Therapeutic Implications
(Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

The Comparison of Different Stretching Intensities on the Range of Motion and Muscle Stiffness of the Quadriceps Muscles
Muscle strain is one of the most frequent sports injuries, having the rectus femoris (RF) muscle as the reported preferred site of quadriceps muscle strain. The decrease muscle stiffness could be an effective RF muscle strain prevention. In recent studies, a high-intensity static stretching intervention decreased passive stiffness, though no study has investigated on the effect of the different static stretching intervention intensities on quadriceps muscle stiffness. The purpose of this study was to investigate the three different quadriceps muscle stiffness intensities (120 vs. 100 vs. 80%). Eighteen healthy, sedentary m...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Activation of Tripartite Motif Containing 63 Expression by Transcription Factor EB and Transcription Factor Binding to Immunoglobulin Heavy Chain Enhancer 3 Is Regulated by Protein Kinase D and Class IIa Histone Deacetylases
ConclusionTFEB and TFE3 activate TRIM63 expression. Both transcription factors are controlled by HDAC4, HDAC5, HDAC7, and all PKD-family members. We propose that the multilevel PKD/HDAC/TFEB/TFE3 network tightly controls TRIM63 expression. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

A 1-Minute Re-warm Up at High-Intensity Improves Sprint Performance During the Loughborough Intermittent Shuttle Test
In conclusion, the RW improved sprint performance, core temperature, muscle activation, and heart rate in the second half of the LIST. The findings suggest that the RW should be recommended for intermittent team sports players when longer RWs are not possible. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Adult and Developing Zebrafish as Suitable Models for Cardiac Electrophysiology and Pathology in Research and Industry
The electrophysiological behavior of the zebrafish heart is very similar to that of the human heart. In fact, most of the genes that codify the channels and regulatory proteins required for human cardiac function have their orthologs in the zebrafish. The high fecundity, small size, and easy handling make the zebrafish embryos/larvae an interesting candidate to perform whole animal experiments within a plate, offering a reliable and low-cost alternative to replace rodents and larger mammals for the study of cardiac physiology and pathology. The employment of zebrafish embryos/larvae has widened from basic science to indust...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Simulating Dynamics of Circulation in the Awake State and Different Stages of Sleep Using Non-autonomous Mathematical Model With Time Delay
We propose a mathematical model of the human cardiovascular system. The model allows one to simulate the main heart rate, its variability under the influence of the autonomic nervous system, breathing process, and oscillations of blood pressure. For the first time, the model takes into account the activity of the cerebral cortex structures that modulate the autonomic control loops of blood circulation in the awake state and in various stages of sleep. The adequacy of the model is demonstrated by comparing its time series with experimental records of healthy subjects in the SIESTA database. The proposed model can become a u...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Characterization of the Temporal Pattern of Blood Protein Digestion in Rhodnius prolixus: First Description of Early and Late Gut Cathepsins
Rhodnius prolixus is one important vector for the parasite Trypanosoma cruzi in Latin America, where Chagas disease is a significant health issue. Although R. prolixus is a model for investigations of vector–parasite interaction and transmission, not much has been done recently to further comprehend its protein digestion. In this work, gut proteolysis was characterized using new fluorogenic substrates, including optimum pH, inhibition profiles, and tissue and temporal expression patterns. Each protease possessed a particular tissue prevalence and activity cycle after feeding. Cathepsin L had a higher activity in the ...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Senescence Is Associated With Elevated Intracellular Resting [Ca2 +] in Mice Skeletal Muscle Fibers. An in vivo Study
Aging causes skeletal muscles to become atrophied, weak, and easily fatigued. Here, we have tested the hypothesis that normal aging in skeletal muscle cells is associated with Ca2+ intracellular dyshomeostasis and oxidative stress. Intracellular Ca2+ concentration ([Ca2+]i), resting intracellular Na+ concentration ([Na+]i) and reactive oxygen species (ROS) production were measured in vivo (superficial gastrocnemius fibers) using double-barreled ion-selective microelectrodes, and in vitro [isolated single flexor digitorum brevis fibers] using fluorescent ROS sensor CM-H2DCFDA in young (3 months of age), middle-aged (12 mont...
Source: Frontiers in Physiology - January 13, 2021 Category: Physiology Source Type: research

Aging, Immunity, and COVID-19: How Age Influences the Host Immune Response to Coronavirus Infections?
The novel coronavirus severe acute respiratory syndrome coronavirus 2 causing the Coronavirus disease (COVID-19) pandemic has ravaged the world with over 72 million total cases and over 1.6 million deaths worldwide as of early December 2020. An overwhelming preponderance of cases and deaths is observed within the elderly population, and especially in those with pre-existing conditions and comorbidities. Aging causes numerous biological changes in the immune system, which are linked to age-related illnesses and susceptibility to infectious diseases. Age-related changes influence the host immune response and therefore not on...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

Physiological Network From Anthropometric and Blood Test Biomarkers
Currently, research in physiology focuses on molecular mechanisms underlying the functioning of living organisms. Reductionist strategies are used to decompose systems into their components and to measure changes of physiological variables between experimental conditions. However, how these isolated physiological variables translate into the emergence -and collapse- of biological functions of the organism as a whole is often a less tractable question. To generate a useful representation of physiology as a system, known and unknown interactions between heterogeneous physiological components must be taken into account. In th...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

The Impact of Polyphenols-Based Diet on the Inflammatory Profile in COVID-19 Elderly and Obese Patients
The World Health Organization declared the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-associated disease (coronavirus disease 2019 – COVID-19) as a pandemic in March 2020. COVID-19 is characterized by cytokine storm, acute respiratory distress syndrome (ARDS), and systemic inflammation–related pathology and already kills more than 1.5 million of people worldwide. Since aged and obese COVID-19 patients exhibit an enhanced inflammatory status, they represent a high-risk cluster for rapidly progressive clinical deterioration. These individuals present comorbid disorders and immunosenescence that ...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

The Gustavus Gene Can Regulate the Fecundity of the Green Peach Aphid, Myzus persicae (Sulzer)
In this study, we report the first investigation of an ortholog of Gus in M. persicae, designated MpGus, and describe its role in the fecundity of this insect. First, we identified the MpGus mRNA sequence in the M. persicae transcriptome database, verified its identity with reverse transcription-polymerase chain reaction (RT-PCR), and then evaluated the transcription levels of MpGus in M. persicae nymphs of different instars and tissues with real-time quantitative PCR (RT-qPCR). To investigate its role in regulating the fecundity of M. persicae, we used RNA interference (RNAi) to silence the expression of MpGus in adult in...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

Human Adaptations to Multiday Saturation on NASA NEEMO
Human adaptation to extreme environments has been explored for over a century to understand human psychology, integrated physiology, comparative pathologies, and exploratory potential. It has been demonstrated that these environments can provide multiple external stimuli and stressors, which are sufficient to disrupt internal homeostasis and induce adaptation processes. Multiday hyperbaric and/or saturated (HBS) environments represent the most understudied of environmental extremes due to inherent experimental, analytical, technical, temporal, and safety limitations. National Aeronautic Space Agency (NASA) Extreme Environm...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

Relationship of the Pro12Ala Polymorphism on the PPARy2 Gene With the Body Composition of Practitioners of Cyclic Exercises
This study aimed to verify the association between the genotypic of the receptor gene activated by peroxisome proliferators gamma 2 (PPARy2) and the body composition and the specific indicators of adiposity in practitioners physical exercises, considering nutritional intake, age, and training load as influencing factors. It was conducted a cross-sectional study with 335 adults (47.9 ± 12.7 years, 138 men, body mass index/BMI = 27.0 ± 4.9 kg/m2), practitioners of aerobic exercises in cyclical modalities (running, walking and/or cycling, who spent 328.3 ± 193.6 kcal/day on physical training). The genotyp...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

Whole-Body Vibration Exercise in Different Postures on Handgrip Strength in Healthy Women: A Cross-Over Study
ObjectiveTo compare the effect of Whole-Body Vibration Exercise (WBVE) applied in push-up modified and half-squat positions, on handgrip strength (HS) and on the electromyography registry (EMGrms) of the flexor digitorum superficialis muscle (FDSM) of the dominant hand.MethodsNineteen healthy women (age 23.40 ± 4.03 years, bodyweight: 58.89 ± 9.87 kg), performed in a randomized order five different tests: (S1) Control; (S2) Push-up modified; (S3) Push-up placebo; (S4); Half-squatting; (S5) Half-squatting placebo. The HS and the EMGrms were assessed at baseline and immediately after the tests. ANOVA two-way de...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

Interlimb Coordination: A New Order Parameter and a Marker of Fatigue During Quasi-Isometric Exercise?
Although exercise-induced fatigue has been mostly studied from a reductionist and component-dominant approach, some authors have started to test the general predictions of theories of self-organized change during exercises performed until exhaustion. However, little is known about the effects of fatigue on interlimb coordination in quasi-isometric actions. The aim of this study was to investigate the effect of exercise-induced fatigue on upper interlimb coordination during a quasi-isometric exercise performed until exhaustion. In order to do this, we hypothesized an order parameter that governs the interlimb coordination a...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

Maturation of the Autonomic Nervous System in Premature Infants: Estimating Development Based on Heart-Rate Variability Analysis
This study aims at investigating the development of premature infants' autonomic nervous system (ANS) based on a quantitative analysis of the heart-rate variability (HRV) with a variety of novel features. Additionally, the role of heart-rate drops, known as bradycardias, has been studied in relation to both clinical and novel sympathovagal indices. ECG data were measured for at least 3 h in 25 preterm infants (gestational age ≤32 weeks) for a total number of 74 recordings. The post-menstrual age (PMA) of each patient was estimated from the RR interval time-series by means of multivariate linear-mixed effects regression....
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

LncRNA H19 as a Competing Endogenous RNA to Regulate AQP Expression in the Intestinal Barrier of IBS-D Patients
ObjectiveThe study aimed to investigate the role of Long non-coding RNA (LncRNA) H19 in the pathogenesis of Diarrhea Irritable Bowel Syndrome (IBS-D), and further to the regulatory effect of LncRNA H19 on AQP1, 3 in the intestinal mucosa of IBS-D patients, so as to seek a new way to elucidate the mechanism of IBS in clinic.MethodsThe levels of LncRNA H19, AQP1, and AQP3 were detected in colonic tissues of IBS-D patients, compared with that in healthy controls. Through RNA gene interference and activation methods, small activating RNA (saRNA) and small interfering (siRNA) were transfered into Caco-2 cells in vitro experimen...
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research

Physical Activity Level Influences MTHFR Gene Methylation Profile in Diabetic Patients
ConclusionWe concluded that insufficient physical activity is associated with partially methylated pattern of MTHFR promoter. (Source: Frontiers in Physiology)
Source: Frontiers in Physiology - January 12, 2021 Category: Physiology Source Type: research