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European Journal of Applied Physiology Jun 2020Low-flow mediated constriction (L-FMC) has emerged as a valuable and complementary measure of flow-mediated dilation (FMD) for assessing endothelial function... (Randomized Controlled Trial)
Randomized Controlled Trial
INTRODUCTION
Low-flow mediated constriction (L-FMC) has emerged as a valuable and complementary measure of flow-mediated dilation (FMD) for assessing endothelial function non-invasively. High dietary sodium has been shown to impair FMD independent of changes in blood pressure (BP), but its effects on L-FMC are unknown.
PURPOSE
To test the hypothesis that high dietary sodium would attenuate brachial artery L-FMC in salt-resistant adults.
METHODS
Fifteen healthy, normotensive adults (29 ± 6 years) participated in a controlled feeding study. Following a run-in diet, participants completed a 7-day low sodium (LS; 20 mmol sodium/day) and 7-day high sodium (HS; 300 mmol sodium/day) diet in randomized order. On the last day of each diet, 24 h urine was collected and assessments of 24 h ambulatory BP and L-FMC were performed. Salt-resistance was defined as a change in 24 h ambulatory mean arterial pressure (MAP) between the LS and HS diets of ≤ 5 mmHg. Resting vascular tone and L-FMC were calculated from ultrasound-derived arterial diameters.
RESULTS
High dietary sodium increased serum sodium and urinary sodium excretion (p < 0.001 for both), but 24 h MAP was unchanged (p = 0.16) by design. High dietary sodium augmented vascular tone (LS: 91 ± 23%, HS: 125 ± 56%, p = 0.01) and attenuated L-FMC (LS: - 0.58 ± 0.99%, HS: 0.17 ± 1.23%, p = 0.008).
CONCLUSION
These findings in salt-resistant adults provide additional evidence that dietary sodium has adverse vascular effects independent of changes in BP.
Topics: Adult; Blood Pressure; Brachial Artery; Female; Humans; Male; Sodium; Sodium Chloride, Dietary; Vasoconstriction; Vasodilation; Young Adult
PubMed: 32306153
DOI: 10.1007/s00421-020-04370-0 -
Journal of Molecular Modeling Apr 2022Thrombin is a Na[Formula: see text]-activated serine protease existing in two forms targeted to procoagulant and anticoagulant activities, respectively. There is one...
Thrombin is a Na[Formula: see text]-activated serine protease existing in two forms targeted to procoagulant and anticoagulant activities, respectively. There is one Na[Formula: see text]-binding site that has been the focus of the study of the thrombin. However, molecular dynamics (MD) simulations suggest that there might be actually two Na[Formula: see text]-binding sites in thrombin and that Na[Formula: see text] ions can even bind to two sites simultaneously. In this study, we performed 12 independent 2-µs all-atom MD simulations for the wild-type (WT) thrombin and we studied the effects of the different Na[Formula: see text] binding modes on thrombin. From the root-mean-square fluctuations (RMSF) for the [Formula: see text]-carbons, we see that the atomic fluctuations mainly change in the 60s, 170s, and 220s loops, and the connection (residue 167 to 170). The correlation matrices for different binding modes suggest regions that may play an important role in thrombin's allosteric response and provide us a possible allosteric pathway for the sodium binding. Amorim-Hennig (AH) clustering tells us how the structure of the regions of interest changes on sodium binding. Principal component analysis (PCA) shows us how the different regions of thrombin change conformation together with sodium binding. Solvent-accessible surface area (SASA) exposes the conformational change in exosite I and catalytic triad. Finally, we argue that the double binding mode might be an inactive mode and that the kinetic scheme for the Na[Formula: see text] binding to thrombin might be a multiple-step mechanism rather than a 2-step mechanism.
Topics: Binding Sites; Ions; Protein Binding; Sodium; Thrombin
PubMed: 35419655
DOI: 10.1007/s00894-022-05076-0 -
PloS One 2017Excess dietary sodium is associated with increased blood pressure (BP). Some drugs are associated with high sodium intake (in particular effervescent tablets), but the... (Review)
Review
BACKGROUND
Excess dietary sodium is associated with increased blood pressure (BP). Some drugs are associated with high sodium intake (in particular effervescent tablets), but the cardiovascular risk associated with such high sodium-containing drugs (HSCD) is largely underevaluated.
OBJECTIVES
To summarize the evidence for a potential cardiovascular risk associated with exposure to HSCD, and to highlight possible risk factors associated with this iatrogenic issue; in general and/or specific populations.
METHODS
We conducted a systematic review, by searching electronic databases including MEDLINE, EMBASE, Web of Science, CENTRAL and grey literature between 1960 and 2015. We included studies that reported modification of cardiovascular parameters or incidence/prevalence of cardiovascular outcomes, between a group of subjects exposed to HSCD relative to a non-exposed group. The threshold used to identify HSCD was 391 mg/day. We did not consider studies evaluating exposure to sodium as an active ingredient or those focusing on dialysis solutions or enteral/parenteral nutrition. Study quality was assessed using the EPHPP tool.
RESULTS
A total of eight studies met our inclusion criteria. Four reported results for short-term exposure to HSCD (≤ 7 days) on BP fluctuations. One study reported an elevation of BP (associated sodium intake: 1,656 mg/day). Four studies evaluated a long-term exposure (≥ 2 years or discontinuation of a chronic treatment). Two studies reported iatrogenic risk. For these studies, drug associated sodium intake was high (> 1,500 mg/day) in patients with comorbidities (in particular, diabetes mellitus and hypertension).
CONCLUSION
Despite numerous study limitations, this systematic review suggests three potential synergistic risk factors for cardiovascular complications after exposure to HSCD: a high sodium intake (≥ 1,500 mg/day), a long duration of exposure, and the presence of comorbidities. Further studies are required to characterize this iatrogenic risk.
TRIAL REGISTRATION
PROSPERO CRD42016047086.
Topics: Cardiovascular Diseases; Humans; Pharmaceutical Preparations; Sodium
PubMed: 28683120
DOI: 10.1371/journal.pone.0180634 -
The Journal of Physiology Jan 19671. Using (24)Na to label the exchangeable sodium in the tissue and either [(35)S]sulphate or [(14)C]sucrose to label the extracellular spaces, the intracellular sodium...
1. Using (24)Na to label the exchangeable sodium in the tissue and either [(35)S]sulphate or [(14)C]sucrose to label the extracellular spaces, the intracellular sodium concentration of frog heart ventricles was determined and found to be between about 5 and 10 m-mole/kg cell water.2. The intracellular potassium concentration, obtained by flame-photometric analysis, was approximately 163 m-mole/kg cell water.3. Two different methods were employed to study the sodium tracer efflux of resting heart ventricles. One involved a double-tracer technique, using (24)Na to indicate the release of the exchangeable tissue sodium, and (35)SO(4) to indicate, approximately, the release of extra-myocardial sodium. In the other a comparison was made of the sodium release from the tissue when it contained sodium either at the normal concentration or at a concentration enhanced by exchange with intracellular potassium.4. The magnitude of the sodium efflux from heart fibres as measured by both methods was of the order 50-100 p-mole/cm(2) sec. Simultaneously with this cellular efflux a substantial amount of sodium was released from extra-myocardial spaces and tissues.5. The net efflux of potassium ions from heart cells that occurred when heart ventricles were perfused with potassium-depleted fluids was determined. The results were used to obtain an indirect estimate, of about 2-3 p-mole/cm(2) sec, for the resting sodium influx.6. The significance of these different values of sodium efflux and influx is discussed.
Topics: Animals; Anura; Carbon Isotopes; Electrophysiology; Extracellular Space; Heart; In Vitro Techniques; Myocardium; Perfusion; Potassium; Sodium; Sodium Isotopes; Sulfur Isotopes; Ventricular Function
PubMed: 6030516
DOI: 10.1113/jphysiol.1967.sp008136 -
Clinical Chemistry and Laboratory... May 2019Moving average quality control (MA QC) was described decades ago as an analytical quality control instrument. Although a potentially valuable tool, it is struggling to... (Review)
Review
Moving average quality control (MA QC) was described decades ago as an analytical quality control instrument. Although a potentially valuable tool, it is struggling to meet expectations due to its complexity and need for evidence-based guidance. For this review, relevant literature and the world wide web were examined in order to (i) explain the basic concepts and current understanding of MA QC, (ii) discuss moving average (MA) optimization methods, (iii) gain insight into practical aspects related to applying MA in daily practice and (iv) describe future prospects to enable more widespread acceptance and application of MA QC. Each of the MA QC optimization methods currently available has their own advantages and disadvantages. Recently developed simulation methods provide realistic error detecting properties for MA QC and are available for laboratories. Operational MA management issues have been identified that allow developers of MA software to upgrade their packages to support optimal MA QC application and guide laboratories on MA management issues, such as MA alarm workup. The new insights into MA QC characteristics and operational issues, together with supporting online tools, may promote more widespread acceptance and application of MA QC.
Topics: Algorithms; Clinical Laboratory Techniques; Limit of Detection; Quality Control; Reproducibility of Results; Sodium
PubMed: 30307894
DOI: 10.1515/cclm-2018-0795 -
Obesity (Silver Spring, Md.) Feb 2018To test the hypothesis that tissue sodium and adipose content are elevated in patients with lipedema; if confirmed, this could establish precedence for tissue sodium and...
OBJECTIVE
To test the hypothesis that tissue sodium and adipose content are elevated in patients with lipedema; if confirmed, this could establish precedence for tissue sodium and adipose content representing a discriminatory biomarker for lipedema.
METHODS
Participants with lipedema (n = 10) and control (n = 11) volunteers matched for biological sex, age, BMI, and calf circumference were scanned with 3.0-T sodium and conventional proton magnetic resonance imaging (MRI). Standardized tissue sodium content was quantified in the calf skin, subcutaneous adipose tissue (SAT), and muscle. Dixon MRI was employed to quantify tissue fat and water volumes of the calf. Nonparametric statistical tests were applied to compare regional sodium content and fat-to-water volume between groups (significance: two-sided P ≤ 0.05).
RESULTS
Skin (P = 0.01) and SAT (P = 0.04) sodium content were elevated in lipedema (skin: 14.9 ± 2.9 mmol/L; SAT: 11.9 ± 3.1 mmol/L) relative to control participants (skin: 11.9 ± 2.0 mmol/L; SAT: 9.4 ± 1.6 mmol/L). Relative fat-to-water volume in the calf was elevated in lipedema (1.2 ± 0.48 ratio) relative to control participants (0.63 ± 0.26 ratio; P < 0.001). Skin sodium content was directly correlated with fat-to-water volume (Spearman's rho = 0.54; P = 0.01).
CONCLUSIONS
Internal metrics of tissue sodium and adipose content are elevated in patients with lipedema, potentially providing objective imaging-based biomarkers for differentially diagnosing the under-recognized condition of lipedema from obesity.
Topics: Adolescent; Adult; Female; Humans; Lipedema; Male; Middle Aged; Skin; Sodium; Subcutaneous Fat
PubMed: 29280322
DOI: 10.1002/oby.22090 -
Nutrients Nov 2023Sodium intake from pre-packaged foods is increasing in China and is well above the WHO recommendation of 5 g per day. The purpose of this study is to analyze the sodium...
Sodium intake from pre-packaged foods is increasing in China and is well above the WHO recommendation of 5 g per day. The purpose of this study is to analyze the sodium content of pre-packaged foods collected by the National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention (NINH, China CDC) in 20 provinces of China from 2017 to 2022. The proportion of pre-packaged foods that meet or exceed the low-sodium, medium-sodium, and high-sodium classifications were analyzed. The proportion of pre-packaged foods that meet and do not meet the WHO global sodium benchmarks and the difference in sodium content between these foods was also calculated. High-sodium foods include sauces, dips, and dressings (3896 mg/100 g), convenience foods (1578 mg/100 g), processed fish products (1470 mg/100 g), processed meat products (1323 mg/100 g), processed poultry products (1240 mg/100 g), snack foods (750 mg/100 g), processed egg products (741 mg/100 g), and fine dried noodles (602 mg/100 g). A large number of pre-packaged foods currently collected in China have a sodium content above sodium benchmarks. This study provided data to support the assessment of sodium intake from pre-packaged foods in the Chinese population and the implementation of comprehensive salt reduction strategies.
Topics: Sodium; Sodium, Dietary; Sodium Chloride, Dietary; Food Labeling; Fast Foods; Food Analysis
PubMed: 38068721
DOI: 10.3390/nu15234862 -
Proceedings of the National Academy of... Mar 2018Transient receptor potential melastatin subfamily member 4 (TRPM4) is a widely distributed, calcium-activated, monovalent-selective cation channel. Mutations in human...
Transient receptor potential melastatin subfamily member 4 (TRPM4) is a widely distributed, calcium-activated, monovalent-selective cation channel. Mutations in human TRPM4 (hTRPM4) result in progressive familial heart block. Here, we report the electron cryomicroscopy structure of hTRPM4 in a closed, Na-bound, apo state at pH 7.5 to an overall resolution of 3.7 Å. Five partially hydrated sodium ions are proposed to occupy the center of the conduction pore and the entrance to the coiled-coil domain. We identify an upper gate in the selectivity filter and a lower gate at the entrance to the cytoplasmic coiled-coil domain. Intramolecular interactions exist between the TRP domain and the S4-S5 linker, N-terminal domain, and N and C termini. Finally, we identify aromatic interactions via π-π bonds and cation-π bonds, glycosylation at an N-linked extracellular site, a pore-loop disulfide bond, and 24 lipid binding sites. We compare and contrast this structure with other TRP channels and discuss potential mechanisms of regulation and gating of human full-length TRPM4.
Topics: Cryoelectron Microscopy; Humans; Models, Molecular; Sodium; TRPM Cation Channels
PubMed: 29463718
DOI: 10.1073/pnas.1722038115 -
Journal of Cosmetic Dermatology Jul 2022Intrinsic aging promotes wrinkles formation by an imbalance between matrix synthesis/degradation in favor of degradation. This is accelerated by the exposome leading to...
BACKGROUND
Intrinsic aging promotes wrinkles formation by an imbalance between matrix synthesis/degradation in favor of degradation. This is accelerated by the exposome leading to overproduction of protease and fewer remodeling.
OBJECTIVE
Protecting the integrity of extracellular matrix appears as the most efficient anti-aging solution. We developed a grafted HA specifically designed to get anti-aging property due to a specific molecular weight and acetylation degree.
METHODS
A transcriptomic analysis was performed on fibroblasts, followed by a measurement of MMP secretion and subsequent effect on collagen degradation. MMP expression in skin explants concerned by chronobiological and extrinsic aging was analyzed by immunostaining. A clinical study was conducted on volunteers presenting wrinkles on face to evaluate flash reduction of wrinkles after 6 h of application by profilometry and anti-aging efficacy after 2 months by VISIA CR2.3.
RESULTS
Transcriptomic analysis evidenced an inhibition of MMP gene expression with acetylated HA, confirmed by an inhibition of MMPs release by fibroblasts, and a protection of type I collagen against degradation. We confirmed the reduction of MMPs in mature skin and in skin explants exposed to UV and urban dust. We demonstrated during clinical studies the flash reduction effect of acetylated HA on crow's feet wrinkles and a filling of nasogenian areas 6 h after application, and a wrinkles number reduction on nasogenian area up to 2 months of application.
CONCLUSION
We developed a new grafted HA owing protective properties against ECM degradation induced by chronobiological and extrinsic aging, leading to a significant and efficient anti-wrinkles effect.
Topics: Aging; Fibroblasts; Humans; Skin; Skin Aging; Sodium
PubMed: 34708918
DOI: 10.1111/jocd.14539 -
Clinical Nutrition ESPEN Oct 2022Dietary sodium restriction is recommended by current guidelines to reduce blood pressure and decrease the risk of cardiovascular disease. Current methods to assess...
BACKGROUND & AIMS
Dietary sodium restriction is recommended by current guidelines to reduce blood pressure and decrease the risk of cardiovascular disease. Current methods to assess sodium intake such as dietary questionnaires and 24-h urine collection are cumbersome, and the results are not readily available to patients. In this analysis, we evaluated using chloride and creatinine dipsticks as a convenient method to monitor sodium intake, in addition to patients' ability to practice this method independently.
METHODS
This is a post-hoc analysis of a previously published trial, LowSalt4Life, that measured change in sodium consumption over 8 weeks to evaluate the effect of a just-in-time adaptive mobile application intervention. Participants were instructed on how to complete and interpret Quantab® chloride and Multistix® PRO 10 LS creatinine dipstick measurements at home and upload a picture of their results. A pharmacy student interpreted the chloride dipsticks, and intraclass correlation coefficients (ICC) were calculated to assess interrater reliability between the participant and pharmacy student. Predicted 24-h sodium values were calculated by the Kawasaki and Mann methods and compared to actual 24-h sodium excretion.
RESULTS
There was a strong interobserver correlation between interpretations of the chloride dipsticks, with the ICC values 0.90, 0.97, 0.99, and 0.98 at weeks 2, 4, 6, and 8, respectively. There was a moderate correlation between the dipstick predicted 24-h sodium excretion and actual 24-h sodium excretion at baseline (r = 0.506; P < 0.001), and a weak correlation at week 8 (r = 0.187; P = 0.217). When corrected creatinine values were used, the dipstick predicted 24-h sodium excretion correlated with the actual 24-h sodium excretion at baseline and week 8 (r = 0.512; P < 0.001 and r = 0.451; P = 0.002).
CONCLUSIONS
Our analysis suggests that chloride and creatinine dipsticks have the potential to predict total daily excretion of sodium. This method provides patients with an easy, convenient, and accurate method to assess sodium excretion at home. Further research is needed to identify the optimal timing of performing the dipstick analysis as well as ways to improve the creatinine measurement of the urine samples.
TRIAL REGISTRATION
ClinicalTrials.gov NCT03099343; https://clinicaltrials.gov/ct2/show/NCT03099343.
Topics: Chlorides; Creatinine; Humans; Hypertension; Reproducibility of Results; Self-Assessment; Sodium; Sodium Radioisotopes; Sodium, Dietary
PubMed: 36184219
DOI: 10.1016/j.clnesp.2022.08.011