The Influence of Dietary Salt Beyond Blood Pressure

HIV-Associated Hypertension: Risks, Mechanisms, and Knowledge Gaps

HIV type 1 (HIV-1) is the causative agent of AIDS. Since the start of the epidemic, HIV/AIDS has been responsible for ≈40 million deaths. Additionally, an estimated 39 million people are currently infected with the virus. HIV-1 primarily infects immune cells, such as CD4+ (cluster of differentiation 4+) T lymphocytes (T cells), and as a consequence, the number of CD4+ T cells progressively declines in people living with HIV. Within a span of ≈10 years, HIV-1 infection leads to the systemic failure of the immune system and progression to AIDS. Fortunately, potent antiviral therapy effectively controls HIV-1 infection and prevents AIDS-related deaths. The efficacy of the current antiviral therapy regimens has transformed the outcome of HIV/AIDS from a death sentence to a chronic disease with a prolonged lifespan of people living with HIV. However, antiviral therapy is not curative, is challenged by virus resistance, can be toxic, and, most importantly, requires lifelong adherence. Furthermore, the improved lifespan has resulted in an increased incidence of non-AIDS-related morbidities in people living with HIV including cardiovascular diseases, renal disease, liver disease, bone disease, cancer, and neurological conditions. In this review, we summarize the current state of knowledge of the cardiovascular comorbidities associated with HIV-1 infection, with a particular focus on hypertension. We also discuss the potential mechanisms known to drive HIV-1-associated hypertension and the knowledge gaps in our understanding of this comorbid condition. Finally, we suggest several directions of future research to better understand the factors, pathways, and mechanisms underlying HIV-1-associated hypertension in the post-antiviral therapy era.

MicroRNA-142-3p alleviated high salt-induced cardiac fibrosis via downregulating optineurin-mediated mitophagy

High salt can induce cardiac damage. The aim of this present study was to explore the effect and the mechanism of microRNA (miR)-142-3p on the cardiac fibrosis induced by high salt. Rats received high salt diet to induce cardiac fibrosis in vivo, and neonatal rat cardiac fibroblasts (NRCF) treated with sodium chloride (NaCl) to induce fibrosis in vitro. The fibrosis and mitochondrial autophagy levels were increased the heart and NRCF treated with NaCl, which were alleviated by miR-142-3p upregulation. The fibrosis and mitochondrial autophagy levels were elevated in NRCF after treating with miR-142-3p antagomiR. Optineurin (OPTN) expression was increased in the mitochondria of NRCF induced by NaCl, which was attenuated by miR-142-3p agomiR. OPTN downregulation inhibited the increases of fibrosis and mitochondrial autophagy levels induced by NaCl in NRCF. These results miR-142-3p could alleviate high salt-induced cardiac fibrosis via downregulation of OPTN to reduce mitophagy.

The Human Gut and Dietary Salt: The Bacteroides/Prevotella Ratio as a Potential Marker of Sodium Intake and Beyond

The gut microbiota is a dynamic ecosystem that plays a pivotal role in maintaining host health. The perturbation of these microbes has been linked to several health conditions. Hence, they have emerged as promising targets for understanding and promoting good health. Despite the growing body of research on the role of sodium in health, its effects on the human gut microbiome remain under-explored. Here, using nutrition and metagenomics methods, we investigate the influence of dietary sodium intake and alterations of the human gut microbiota. We found that a high-sodium diet (HSD) altered the gut microbiota composition with a significant reduction in Bacteroides and inverse increase in Prevotella compared to a low-sodium diet (LSD). However, there is no clear distinction in the Firmicutes/Bacteroidetes (F/B) ratio between the two diet types. Metabolic pathway reconstruction revealed the presence of sodium reabsorption genes in the HSD, but not LSD. Since it is currently difficult in microbiome studies to confidently associate the F/B ratio with what is considered healthy (e.g., low sodium) or unhealthy (e.g., high sodium), we suggest that the use of a genus-based ratio such as the Bacteroides/Prevotella (B/P) ratio may be more beneficial for the application of microbiome studies in health.

A review of the world's salt reduction policies and strategies - preparing for the upcoming year 2025

Excessive consumption of dietary sodium is a significant contributor to non-communicable diseases, including hypertension and cardiovascular disease. There is now a global consensus that regulating salt intake is among the most cost-effective measures for enhancing public health. More than half of the countries worldwide have implemented multiple strategies to decrease salt consumption. Nevertheless, a report on sodium intake reduction published by the World Health Organization revealed that the world is off-track to meet its targeted reduction of 30% by 2025. The global situation regarding salt reduction remains concerning. This review will center on domestic and international salt reduction policies, as well as diverse strategies, given the detrimental effects of excessive dietary salt intake and the existing global salt intake scenario. Besides, we used visualization software to analyze the literature related to salt reduction research in the last five years to explore the research hotspots in this field. Our objective is to enhance public awareness regarding the imperative of reducing salt intake and promoting the active implementation of diverse salt reduction policies.

Mechanical Stress Induces Sodium Entry and Osmoprotective Responses in Murine Synovial Fibroblasts

Osteoarthritis (OA) is a multifactorial disease depending on molecular, genetic, and environmental factors like mechanical strain. Next to the cartilage and the subchondral bone, OA also affects the synovium, which is critically involved in the maintenance of joint homeostasis. As there is a correlation between the extracellular sodium content in the knee joint and OA, this study investigates the impact of sodium on OA-associated processes like inflammation and bone remodeling without and with mechanical loading in synovial fibroblasts. For that purpose, murine synovial fibroblasts from the knee joint were exposed to three different extracellular sodium chloride concentrations (-20 mM, ±0 mM and +50 mM NaCl) in the absence or presence of compressive or intermittent tensile strain. In addition to the intracellular Na+ content and gene expression of the osmoprotective transcription factor nuclear factor of activated T cells 5 (Nfat5), the gene and protein expression of inflammatory mediators (interleukin-6 (IL6), prostaglandin endoperoxide synthase-2 (Ptgs2)/prostaglandin E2 (PGE2)), and factors involved in bone metabolism (receptor activator of NF-κB ligand (RANKL), osteoprotegerin (OPG)) were analyzed by qPCR and ELISA. Mechanical strain already increased intracellular Na+ and Nfat5 gene expression at standard salt conditions to levels obtained by exposure to increased extracellular Na+ content. Both high salt and compressive strain resulted in elevated IL6 and PGE2 release. Intermittent tensile strain did not increase Il6 mRNA expression or IL6 protein secretion but triggered Ptgs2 expression and PGE2 production. Increased extracellular Na+ levels and compressive strain increased RANKL expression. In contrast, intermittent tension suppressed RANKL expression without this response being subject to modification by extracellular sodium availability. OPG expression was only induced by compressive strain. Changes in extracellular Na+ levels modified the inflammatory response and altered the expression of mediators involved in bone metabolism in cells exposed to mechanical strain. These findings indicate that Na+ balance and Nfat5 are important players in synovial fibroblast responses to mechanical stress. The integration of Na+ and Na+-dependent signaling will help to improve the understanding of the pathogenesis of osteoarthritis and could lead to the establishment of new therapeutic targets.

European stroke organisation (ESO) guideline on cerebral small vessel disease, part 2, lacunar ischaemic stroke

A quarter of ischaemic strokes are lacunar subtype, typically neurologically mild, usually resulting from intrinsic cerebral small vessel pathology, with risk factor profiles and outcome rates differing from other stroke subtypes. This European Stroke Organisation (ESO) guideline provides evidence-based recommendations to assist with clinical decisions about management of lacunar ischaemic stroke to prevent adverse clinical outcomes. The guideline was developed according to ESO standard operating procedures and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. We addressed acute treatment (including progressive lacunar stroke) and secondary prevention in lacunar ischaemic stroke, and prioritised the interventions of thrombolysis, antiplatelet drugs, blood pressure lowering, lipid lowering, lifestyle, and other interventions and their potential effects on the clinical outcomes recurrent stroke, dependency, major adverse cardiovascular events, death, cognitive decline, mobility, gait, or mood disorders. We systematically reviewed the literature, assessed the evidence and where feasible formulated evidence-based recommendations, and expert concensus statements. We found little direct evidence, mostly of low quality. We recommend that patients with suspected acute lacunar ischaemic stroke receive intravenous alteplase, antiplatelet drugs and avoid blood pressure lowering according to current acute ischaemic stroke guidelines. For secondary prevention, we recommend single antiplatelet treatment long-term, blood pressure control, and lipid lowering according to current guidelines. We recommend smoking cessation, regular exercise, other healthy lifestyle modifications, and avoid obesity for general health benefits. We cannot make any recommendation concerning progressive stroke or other drugs. Large randomised controlled trials with clinically important endpoints, including cognitive endpoints, are a priority for lacunar ischaemic stroke.

The current state of evidence for sodium and fluid restriction in heart failure

The field of heart failure has evolved in terms of the therapies that are available including pharmaceutical and device therapies. There is now substantial randomized trial data to indicate that dietary sodium restriction does not provide the reduction in clinical events with accepted heterogeneity in the clinical trial results. Dietary sodium restriction should be considered for some but not all patients and with different objectives than clinical outcomes but instead for potential quality of life benefit. In addition, fluid restriction, once the mainstay of clinical practice, has not shown to be of any additional benefit for patients in hospital or in the ambulatory care setting and therefore should be considered to be used cautiously (if at all) in clinical practice. Further developments and clinical trials are needed in this area to better identify patients who may benefit or have harm from these lower cost interventions and future research should focus on large scale, high quality, clinical trials rather than observational data to drive clinical practice.

Salty Subjects: Unpacking Racial Differences in Salt-Sensitive Hypertension

PURPOSE OF REVIEW

To review underlying mechanisms and environmental factors that may influence racial disparities in the development of salt-sensitive blood pressure.

RECENT FINDINGS

Our group and others have observed racial differences in diet and hydration, which may influence salt sensitivity. Dietary salt elicits negative alterations to the gut microbiota and immune system, which may increase hypertension risk, but little is known regarding potential racial differences in these physiological responses. Antioxidant supplementation and exercise offset vascular dysfunction following dietary salt, including in Black adults. Furthermore, recent work proposes the role of racial differences in exposure to social determinants of health, and differences in health behaviors that may influence risk of salt sensitivity. Physiological and environmental factors contribute to the mechanisms that manifest in racial differences in salt-sensitive blood pressure. Using this information, additional work is needed to develop strategies that can attenuate racial disparities in salt-sensitive blood pressure.

Effects of Behavioral Interventions for Salt Reduction on Blood Pressure and Urinary Sodium Excretion: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Hypertension is a prevalent cardiovascular condition, with excessive sodium intake being a significant risk factor. Various studies have investigated measures to reduce salt intake, including integrated lifestyle interventions and health education. However, the effectiveness of behavioral interventions focused solely on salt reduction remains unclear. This systematic review and meta-analysis aimed to investigate the effects of a behavioral intervention based on salt reduction on blood pressure and urinary sodium excretion. A comprehensive search of the Cochrane Central Register of Controlled Trials, EMBASE, PubMed, and Web of Science was conducted to identify relevant literature. Study and intervention characteristics were extracted for descriptive synthesis, and the quality of the included studies was assessed. A total of 10 studies, comprising 4,667 participants (3,796 adults and 871 children), were included. The interventions involved the provision of salt-restriction spoons or devices, salt-reduction education, self-monitoring devices for urinary sodium, and salt-reduction cooking classes. Meta-analysis results showed that behavioral interventions focused on salt reduction significantly reduced systolic blood pressure (SBP) (-1.17 mmHg; 95% CI, -1.86 to -0.49), diastolic blood pressure (DBP) (-0.58 mmHg; 95% CI, -1.07 to -0.08) and urinary sodium excretion (-21.88 mmol/24 hours; 95% CI, -32.12 to -11.64). These findings suggest that behavioral change interventions centered on salt reduction can effectively lower salt intake levels and decrease blood pressure levels. However, to enhance effectiveness, behavioral interventions for salt reduction should be combined with other salt-reduction strategies.

Melatonin supplementation does not alter vascular function or oxidative stress in healthy normotensive adults on a high sodium diet

High sodium diets (HSD) can cause vascular dysfunction, in part due to increases in reactive oxygen species (ROS). Melatonin reduces ROS in healthy and clinical populations and may improve vascular function. The purpose was to determine the effect of melatonin supplementation on vascular function and ROS during 10 days of a HSD. We hypothesized that melatonin supplementation during a HSD would improve vascular function and decrease ROS levels compared to HSD alone. Twenty-seven participants (13 M/14 W, 26.7 ± 2.9 years, BMI: 23.6 ± 2.0 kg/m2 , BP: 110 ± 9/67 ± 7 mmHg) were randomized to a 10-day HSD (6900 mg sodium/d) supplemented with either 10 mg of melatonin (HSD + MEL) or a placebo (HSD + PL) daily. Brachial artery flow-mediated dilation, a measure of macrovascular function, (HSD + PL: 7.1 ± 3.8%; HSD + MEL: 6.7 ± 3.4%; p = 0.59) and tissue oxygenation index (TSI) reperfusion rate, a measure of microvascular reactivity, (HSD + PL: 0.21 ± 0.06%/s; HSD + MEL: 0.21 ± 0.08%/s; p = 0.97) and TSI area under the curve (HSD + PL: 199899 ± 10,863 a.u.; HSD + MEL: 20315 ± 11,348 a.u.; p = 0.17) were similar at the end of each condition. Neither nitroxide molarity (HSD + PL: 7.8 × 10-5  ± 4.1 × 10-5 mol/L; HSD + MEL: 8.7 × 10-5  ± 5.1 × 10-5 mol/L; p = 0.55) nor free radical number (HSD + PL: 8.0 × 1015  ± 4.4 × 1015 ; HSD + MEL: 9.0 × 1015  ± 4.9 × 1015 ; p = 0.51) were different between conditions. Melatonin supplementation did not alter vascular function or ROS levels while on a HSD in this sample of young healthy normotensive adults.

Bioactive Peptides from Ruditapes philippinarum Attenuate Hypertension and Cardiorenal Damage in Deoxycorticosterone Acetate-Salt Hypertensive Rats

Hypertension is a common disease that affects human health and can lead to damage to the heart, kidneys, and other important organs. In this study, we investigated the regulatory effects of bioactive peptides derived from Ruditapes philippinarum (RPP) on hypertension and organ protection in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. We found that RPPs exhibited significant blood pressure-lowering properties. Furthermore, the results showed that RPPs positively influenced vascular remodeling and effectively maintained a balanced water-sodium equilibrium. Meanwhile, RPPs demonstrated anti-inflammatory potential by reducing the serum levels of inflammatory cytokines (TNF-α, IL-2, and IL-6). Moreover, we observed the strong antioxidant activity of RPPs, which played a critical role in reducing oxidative stress and alleviating hypertension-induced damage to the aorta, heart, and kidneys. Additionally, our study explored the regulatory effects of RPPs on the gut microbiota, suggesting a possible correlation between their antihypertensive effects and the modulation of gut microbiota. Our previous studies have demonstrated that RPPs can significantly reduce blood pressure in SHR rats. This suggests that RPPs can significantly improve both essential hypertension and DOAC-salt-induced secondary hypertension and can ameliorate cardiorenal damage caused by hypertension. These findings further support the possibility of RPPs as an active ingredient in functional anti-hypertensive foods.

The Relationship between Resistant Hypertension and Advanced Glycation End-Product Levels Measured Using the Skin Autofluorescence Method: A Case-Control Study

Resistant hypertension is hypertension that cannot be controlled despite the use of three antihypertensive drugs, one of which is a diuretic. Resistant hypertension often coexists with advanced age, obesity, smoking, and diabetes. Advanced glycation end products (AGEs) are substances that are generated as a result of the glycation of proteins, lipids, and nucleic acids due to conditions such as hyperlipidemia, oxidative stress, and hyperglycemia. There are studies showing the relationships between AGE levels and aortic stiffness, hypertension, and microvascular and macrovascular complications in diabetes. In our study, we examined the relationship between resistant hypertension and AGE levels. Our study was planned as a case-control study, and 88 patients with resistant hypertension were included in the focus group, while 88 patients with controlled hypertension were included in the control group. The AGE levels of the patients were measured using the skin autofluorescence method. AGE levels were found to be significantly higher in patients with resistant hypertension than those recorded in the control group. A significant increase in AGE levels was also observed in patients with resistant hypertension and without diabetes compared with the control group. The levels of AGEs, which can be measured cheaply, noninvasively, and quickly with the skin autofluorescence method, may provide benefits in identifying these patients with resistant hypertension.

Measured sodium excretion is associated with cardiovascular outcomes in non-dialysis CKD patients: results from the KNOW-CKD study

Background

There are insufficient studies on the effect of dietary salt intake on cardiovascular (CV) outcomes in chronic kidney disease (CKD) patients, and there is no consensus on the sodium (Na) intake level that increases the risk of CV disease in CKD patients. Therefore, we investigated the association between dietary salt intake and CV outcomes in CKD patients.

Methods

In the Korean cohort study for Outcome in patients with CKD (KNOW-CKD), 1,937 patients were eligible for the study, and their dietary Na intake was estimated using measured 24h urinary Na excretion. The primary outcome was a composite of CV events and/or all-cause death. The secondary outcome was a major adverse cardiac event (MACE).

Results

Among 1,937 subjects, there were 205 (10.5%) events for the composite outcome and 110 (5.6%) events for MACE. Compared to the reference group (urinary Na excretion< 2.0g/day), the group with the highest measured 24h urinary Na excretion (urinary Na excretion ≥ 8.0g/day) was associated with increased risk of both the composite outcome (hazard ratio 3.29 [95% confidence interval 1.00-10.81]; P = 0.049) and MACE (hazard ratio 6.28 [95% confidence interval 1.45-27.20]; P = 0.013) in a cause-specific hazard model. Subgroup analysis also showed a pronounced association between dietary salt intake and the composite outcome in subgroups of patients with abdominal obesity, female, lower estimated glomerular filtration rate (< 60 ml/min per 1.73m2), no overt proteinuria, or a lower urinary potassium-to-creatinine ratio (< 46 mmol/g).

Conclusion

A high-salt diet is associated with CV outcomes in non-dialysis CKD patients.

Intestinal Cckbr-specific knockout mouse as a novel model of salt-sensitive hypertension via sodium over-absorption

OBJECTIVES

To investigate the value of CCKBRfl/fl villin-Cre mice as a mouse model of salt-sensitive hypertension (SSH).

METHODS

In the first part, 2-month-old CCKBRfl/fl villin-Cre mice (CKO) and control CCKBRfl/fl mice (WT) were fed with normal diet (0.4% NaCl) or high salt diet (4% NaCl), separately for 6 weeks. In the rescue study, one week of hydrochlorothiazide or saline injection were treated with the CKO mice fed high salt diet. The blood pressure, biochemical indexes, and the expression of small intestinal sodium transporters (NHE3, NKCC1, eNaC) was detected. The organ injury markers (MMP2/MMP9) and the histopathological changes of kidneys were observed, whereas the changes of duodenal sodium absorption were detected by small intestinal perfusion in vivo.

RESULTS

The CCKBRfl/fl villin-Cre mice with high salt intake exhibited high blood pressure, increased duodenal sodium absorption and urinary sodium excretion, and with renal injury. The protein expression of NHE3, NKCC1 and eNaC were also significant increase in the intestine of CKO-HS mice. Treatment with hydrochlorothiazide remarkably attenuated the elevated blood pressure by high salt absorption in the CCKBRfl/fl villin-Cre mice, but no significant histopathological changes were observed.

CONCLUSIONS

These results support a crucial role of intestinal Cckbr deficiency on SSH development and the diuretic antihypertension effect in CCKBRfl/fl villin-Cre mice. The CCKBRfl/fl villin-Cre mice with the high salt intake may serve as a stable model of salt-sensitive hypertensive induced by sodium overloading.

Effects of a high salt diet on blood pressure dipping and the implications on hypertension

High blood pressure, also known as hypertension, is a major risk factor for cardiovascular disease. Salt intake has been shown to have a significant impact on BP, but the mechanisms by which it influences the blood pressure dipping pattern, and 24-h blood pressure remains controversial. This literature review aims to both summarize the current evidence on high salt diet induced hypertension and discuss the epidemiological aspects including socioeconomic issues in the United States and abroad. Our review indicates that a high salt diet is associated with a blunted nocturnal blood pressure dipping pattern, which is characterized by a reduced decrease in blood pressure during the nighttime hours. The mechanisms by which high salt intake affects blood pressure dipping patterns are not fully understood, but it is suggested that it may be related to changes in the sympathetic nervous system. Further, we looked at the association between major blood pressure and circadian rhythm regulatory centers in the brain, including the paraventricular nucleus (PVN), suprachiasmatic nucleus (SCN) and nucleus tractus solitarius (nTS). We also discuss the underlying social and economic issues in the United States and around the world. In conclusion, the evidence suggests that a high salt diet is associated with a blunted, non-dipping, or reverse dipping blood pressure pattern, which has been shown to increase the risk of cardiovascular disease. Further research is needed to better understand the underlying mechanisms by which high salt intake influences changes within the central nervous system.

Glycocalyx-Sodium Interaction in Vascular Endothelium

The glycocalyx generally covers almost all cellular surfaces, where it participates in mediating cell-surface interactions with the extracellular matrix as well as with intracellular signaling molecules. The endothelial glycocalyx that covers the luminal surface mediates the interactions of endothelial cells with materials flowing in the circulating blood, including blood cells. Cardiovascular diseases (CVD) remain a major cause of morbidity and mortality around the world. The cardiovascular risk factors start by causing endothelial cell dysfunction associated with destruction or irregular maintenance of the glycocalyx, which may culminate into a full-blown cardiovascular disease. The endothelial glycocalyx plays a crucial role in shielding the cell from excessive exposure and absorption of excessive salt, which can potentially cause damage to the endothelial cells and underlying tissues of the blood vessels. So, in this mini review/commentary, we delineate and provide a concise summary of the various components of the glycocalyx, their interaction with salt, and subsequent involvement in the cardiovascular disease process. We also highlight the major components of the glycocalyx that could be used as disease biomarkers or as drug targets in the management of cardiovascular diseases.

Potential impact of ambient temperature on maternal blood pressure and hypertensive disorders of pregnancy: A nationwide multicenter study based on the China birth cohort

Limited evidence exists regarding the association between ambient temperature and blood pressure (BP) level of pregnant women. To investigate the associations of ambient temperature with maternal BP and hypertensive disorders of pregnancy (HDP), we studied 105,063 participants in 38 centers of 17 provinces from November 2017 to December 2021. BP was measured with standardized automated digital sphygmomanometers. Ambient temperature was classified into five classes as very hot, moderate hot, mild, moderate cold, and very cold. Generalized linear mixed models were used to investigate the ambient temperature-BP/HDP associations, controlling for multiple covariates. No significant associations of first-trimester ambient temperature with maternal BP and HDP prevalence were observed. Compared with mild temperature, second-trimester very cold and second-trimester moderate cold were statistically associated with the increase of 1.239 mmHg (95% CI: 0.908, 1.569) and 0.428 mmHg (95% CI: 0.099, 0.757) for second-trimester systolic blood pressure (SBP), respectively. Similar trends were also observed in the association between second-trimester cold exposure and second-trimester diastolic blood pressure (DBP), in the association between second-trimester cold exposure and third-trimester SBP/DBP as well as in the association between third-trimester cold exposure and third-trimester SBP/DBP although some estimates were not statistically significant. Furthermore, in the second and third trimester, very cold [second trimester: adjusted odds ratio (aOR) = 1.298; third trimester: aOR = 1.236) and moderate cold (second trimester: aOR = 1.208; third trimester: aOR = 1.146) exposures also increased the odds of HDP, and these associations were stronger among participants aged ≥35 years or from North China. The second and third trimesters are the critical exposure windows for ambient temperature exposure-BP/HDP associations. During this period, exposure to cold ambient temperature was associated with elevated BP as well as increased HDP prevalence among most Chinese pregnant women, those aged ≥35 years or from North China being more vulnerable.

Be aware of the sodium intake outside student canteens: development and validation of a sodium food frequency questionnaire in Chinese undergraduates

Background

Chinese college students used to eat in student canteens, making dietary consumption outside the cafeterias the main reason for the difference in sodium intake. This study aims to develop and validate a food frequency questionnaire (Sodium-FFQ) targeting dietary sodium intake outside the canteens among undergraduates in China.

Methods

This cross-sectional study included 124 and 81 college students from comprehensive universities in the development and validation stage. A 24 h dietary recall and a food frequency questionnaire were used to develop the Sodium-FFQ. Food items were selected according to the foods that contributed more to the total sodium intake. Test-retest correlation coefficients with an interval of 14 days were employed to evaluate reproducibility. Validity was assessed against a single 24 h urine collection and a 3-day dietary record using correlation coefficients, Bland-Altman analyses, and cross-classification analysis of Kappa coefficients.

Results

The Sodium-FFQ consists of 12 groups of foods with 48 items. The Spearman correlation coefficient of test-retest on sodium intake was 0.654 (p < 0.05), and that between the Sodium-FFQ, 3 × 24 h dietary record, and 24-h urinary sodium were 0.393 (p < 0.05) and 0.342 (p < 0.05), respectively. The Sodium-FFQ was correlated to 24 h urinary sodium-to-potassium ratio, with a Spearman coefficient of 0.370 (p < 0.05). The classification agreement of the Sodium-FFQ and 24 h urinary sodium was 68.4%, and the Kappa coefficient was 0.371 (p < 0.001).

Conclusion

The Sodium-FFQ developed in this study presented an acceptable reproducibility, validity, and classification agreement. It indicates that the Sodium-FFQ could be a potential tool for promoting sodium restriction in college students.

Identification and characterisation of taste-enhancing peptides from oysters (Crassostrea gigas) via the Maillard reaction

Oysters, which are flavourful edible marine products, have been utilised to produce Maillard reaction products (MRPs), which contribute to saltiness enhancement. Here, the molecular weight distribution, free amino acids, and taste characteristics of MRPs were analysed, while ultraviolet light was used to observe the Maillard reaction. Both thermal degradation and cross-linking reactions occur during the Maillard reaction. When the Maillard reaction time was 90 min, the saltiness, umami, and richness of the MRPs peaked, however bitterness reached its lowest value. Moreover, at an MRP concentration of 1.5 mg/mL, salts were reduced by 35.71% in a 3 mg/mL sodium chloride solution without reducing saltiness, based on sensory evaluation. Glycation sites of the MRPs, which are crucial for saltiness enhancement and derived from a variety of protein sources, were determined using nano-HPLC-MS/MS analysis. Our study establishes the foundation for preparing salt-enhancing peptides, accelerating the popularisation of oyster-derived flavouring agents.

Preparation of Saltiness-Enhancing Enzymatic Hydrolyzed Pea Protein and Identification of the Functional Small Peptides of Salt Reduction

According to the correlation of saltiness determined by electronic tongue and perceived NaCl concentration, favorable enzymatic hydrolysis parameters were achieved to prepare the saltiness enhancing mixture peptides from pea protein. Six peptide fractions (F1, F2, F3, F4, F5, and F6) were isolated using Sephadex G-10 gel filtration. Among them, fraction F4 (0.1%) exhibited the highest saltiness (5.90 ± 0.03). The amino acid sequences of five main peptides identified by time-of-flight mass spectrometry were Tyr-Trp (367.40 Da), Gly-Glu-His-Glu (470.43 Da), Glu-Arg-Phe-Gly-Pro (604.65 Da), Gly-Ala-Gly-Lys (331.37 Da), and Pro-Gly-Ala-Gly-Asn (414.41 Da). Tyr-Trp (0.01%) in 0.4% NaCl solution had a 20% saltiness-enhancement compared with 0.4% NaCl solution. More salivary aldosterone was secreted after tasting hydrolysate or Tyr-Trp solutions via enzyme-linked immunosorbent assay, reflecting the improvement of human sensitivity to saltiness. Thereby, the saltiness-enhancing effect was confirmed for the small peptides from hydrolyzed pea protein and the main contributor was further identified.

Short-term high-salt consumption does not influence resting or exercising heart rate variability but increases MCP-1 concentration in healthy young adults

High salt consumption increases blood pressure (BP) and cardiovascular disease risk by altering autonomic function and increasing inflammation. However, it is unclear whether salt manipulation alters resting and exercising heart rate variability (HRV), a noninvasive measure of autonomic function, in healthy young adults. The purpose of this investigation was to determine whether short-term high-salt intake 1) alters HRV at rest, during exercise, or exercise recovery and 2) increases the circulating concentration of the inflammatory biomarker monocyte chemoattractant protein 1 (MCP-1). With the use of a randomized, placebo-controlled, crossover study, 20 participants (8 females; 24 ± 4 yr old, 110 ± 10/64 ± 8 mmHg) consumed salt (3,900 mg sodium) or placebo capsules for 10 days each separated by ≥2 wk. We assessed HRV during 10 min of baseline rest, 50 min of cycling (60% V̇o2peak), and recovery. We quantified HRV using the standard deviation of normal-to-normal RR intervals, the root mean square of successive differences (RMSSD), and additional time and frequency domain metrics of HRV. Plasma samples were collected to assess MCP-1 concentration. No main effect of high salt or condition × time interaction was observed for HRV metrics. However, acute exercise reduced HRV (e.g., RMSSD time: P < 0.001, condition: P = 0.877, interaction: P = 0.422). High salt elevated plasma MCP-1 (72.4 ± 12.5 vs. 78.14 ± 14.7 pg/mL; P = 0.010). Irrespective of condition, MCP-1 was moderately associated (P values < 0.05) with systolic (r = 0.32) and mean BP (r = 0.33). Short-term high-salt consumption does not affect HRV; however, it increases circulating MCP-1, which may influence BP in young adults.

High sodium intake differentially impacts brachial artery dilation when evaluated with reactive versus active hyperemia in salt resistant individuals

This study sought to determine if high sodium (HS) intake in salt resistant (SR) individuals attenuates upper limb arterial dilation in response to reactive (occlusion) and active (exercise) hyperemia, two stimuli with varying vasodilatory mechanisms, and the role of oxidative stress in this response. Ten young, SR participants (9 males, 1 female) consumed a 7-day HS (6,900 mg/day) and a 7-day recommended sodium intake (RI: 2,300 mg/day) diet in a randomized order. On the last day of each diet, brachial artery (BA) function was evaluated via reactive (RH-FMD: 5 min of cuff occlusion) and active [handgrip (HG) exercise] hyperemia after consumption of both placebo (PL) and antioxidants (AO). The HS diet significantly elevated sodium excretion (P < 0.05), but mean arterial blood pressure was unchanged. During the PL condition, the HS diet significantly reduced RH-FMD when compared with RI diet (P = 0.01), but this reduction was significantly restored (P = 0.01) when supplemented with AO (HS + PL: 5.9 ± 3.4; HS + AO: 8.2 ± 2.7; RI + PL: 8.9 ± 4.7; RI + AO: 7.0 ± 2.1%). BA shear-to-dilation slopes, evaluated across all HG exercise workloads, were not significantly different across sodium intervention or AO supplementation. In SR individuals, HS intake impaired BA function when assessed via RH-FMD, but was restored with acute AO consumption suggesting oxidative stress as a contributor to this dysfunction. However, exercise-induced BA dilation was unaltered, potentially implicating an inability of HS intake to influence the mechanisms responsible for effectively maintaining skeletal muscle perfusion during exercise.NEW & NOTEWORTHY This study examined if high sodium (HS) intake in salt resistant (SR) individuals attenuates brachial artery (BA) flow-mediated dilation in response to reactive (occlusion) and active (exercise) hyperemia. In SR individuals, HS intake impaired reactive hyperemia-induced BA dilation, but not exercise-induced BA dilation. This finding suggests that although brachial artery nitric oxide bioavailability may be reduced following HS intake, the redundant mechanisms associated with adequate upper limb blood flow regulation during exercise are maintained.

Etiological Diagnosis and Personalized Therapy for Hypertension: A Hypothesis of the REASOH Classification

With the epidemic of risk factors such as unhealthy lifestyle, obesity and mental stress, the prevalence of hypertension continues to rise across the world. Although standardized treatment protocols simplify the selection of antihypertensive drugs and ensure therapeutic efficacy, the pathophysiological state of some patients remains, which may also lead to the development of other cardiovascular diseases. Thus, there is an urgent need to consider the pathogenesis and selection of antihypertensive drug for different type of hypertensive patients in the era of precision medicine. We proposed the REASOH classification, based on the etiology of hypertension, including renin-dependent hypertension, elderly-arteriosclerosis-based hypertension, sympathetic-active hypertension, secondary hypertension, salt-sensitive hypertension and hyperhomocysteinemia hypertension. The aim of this paper is to propose a hypothesis and provide a brief reference for the personalized treatment of hypertensive patients.

Coexistence of high content of critical nutrients and claims in food products targeted at Brazilian children

ABSTRACT Objective: This study aimed to evaluate food labels targeted at children and identify the concomitant presence of claims and high levels of critical nutrients and/or the presence of sweeteners. As a secondary objective, it aimed to list different types of claims and check which marketing strategies are most used. Methods: We collected 409 products, from 8 popular food groups targeted at children, in Brazilian market (i.e., fruit drinks, dairy drinks, sandwich cookies, cakes, breakfast cereals, jellies, corn snacks, and yogurts). The contents of critical nutrients (e.g., sugar, total fat, saturated fat, and trans-fat, and sodium) and presence/absence of sweetener were calculated, considering Pan American Health Organization (PAHO) parameters. Then, we verified the presence and types of claims in these products. Results: Overall, 265 (64.7%) labels presented claims. In three of the eight categories (i.e., breakfast cereals, dairy drinks, and yogurt), all products with claims (50, 34, and 34 products, respectively) had one or more nutrients in harmful concentrations (critical nutrients above PAHO’s nutritional profile and/or presence of sweeteners). In the other categories, only one product (of 63 sandwich cookies and 26 breakfast cereals with claims) and three products (of 22 cakes and 28 jellies with claims) had no nutrient in critical concentration. The presence of claims, like “rich/source” of micronutrient, was predominant in seven of the eight food groups. Conclusion: In the present study, there was a high presence of claims, of different types, in foods targeted at children, which, for the most part, also have excess of at least one critical nutrient, according to PAHO.

The relationship between physicochemical and microbiological characteristics of Surk cheese

In this study, the relationship between the physicochemical and microbiological properties of the Surk cheese was investigated through the analysis of dry matter (D.M.), ash, protein, salt, acidity, pH and enumeration of the total mesophyll aerobic bacteria (TMAB), yeast-mold, presumptive lactobacilli and lactococci. Surk samples were obtained randomly from 36 different local dairy shops in Antakya province of Turkey. The average values of the dry matter, ash, protein, fat, and salt, acidity and pH analysis were 44.4%, 9.09%, 17.5%, 17.0%, 8.08%, 0.916% and 4.17, respectively. The average values for TMAB, yeast mold, presumptive lactobacilli and lactococci enumeration in the microbiological analysis were found to be 6.23, 4.09, 6.04, and 3.42 log cfu/g, respectively. Based on the statistical analysis, Surk samples were divided into 3 groups in terms of salt content (3-6, 6-9 and > 9%). Then, the physicochemical and microbiological properties of Surk samples were evaluated according to these groups. This study suggests that besides the different methods to produce Surk cheese as followed by the different manufacturers, the amount of salt added to Surk cheese affects its microbiological and physicochemical characteristics.

Mechanisms of sodium-mediated injury in cardiovascular disease: old play, new scripts

There is a strong association between salt intake and cardiovascular diseases, particularly hypertension, on the population level. The mechanisms that explain this association remain incompletely understood and appear to extend beyond blood pressure. In this review, we describe some of the 'novel' roles of Na⁺ in cardiovascular health and disease: energetic implications of sodium handling in the kidneys; local accumulation in tissue; fluid dynamics; and the role of the microvasculature, with particular focus on the lymphatic system. We describe the interplay between these factors that involves body composition, metabolic signatures, inflammation and composition of the extracellular and intracellular milieus.

Molecular logic of salt taste reception in special reference to transmembrane channel-like 4 (TMC4)

The taste is biologically of intrinsic importance. It almost momentarily perceives environmental stimuli for better survival. In the early 2000s, research into taste reception was greatly developed with discovery of the receptors. However, the mechanism of salt taste reception is not fully elucidated yet and many questions still remain. At present, next-generation sequencing and genome-editing technologies are available which would become pivotal tools to elucidate the remaining issues. Here we review current mechanisms of salt taste reception in particular and characterize the properties of transmembrane channel-like 4 as a novel salt taste-related molecule that we found using these sophisticated tools.

High salt intake damages myocardial viability and induces cardiac remodeling via chronic inflammation in the elderly

Background

The heart is an important target organ for the harmful effects of high dietary salt intake. However, the effects and associations of high salt intake on myocardial viability, cardiac function changes, and myocardial remodeling are unclear.

Methods

A total of 3,810 participants aged 60 years and older were eligible and enrolled from April 2008 to November 2010 and from August 2019 to November 2019 in the Shandong area of China. Salt intake was estimated using 24-h urine collection consecutively for 7 days. Myocardial strain rates, cardiac function and structure, and serum high-sensitivity C-reactive protein (hsCRP) levels were assessed. Participants were classified into low (n = 643), mild (n = 989), moderate (n = 1,245), and high (n = 933) groups, corresponding to < 6, 6–9, 9–12, and >12 g/day of salt intake, respectively, depending on the salt intake estimation.

Results

The global early diastolic strain rate (SRe) and late diastolic strain rate (SRa) in the high group were 1.58 ± 0.26, 1.38 ± 0.24. respectively, and significantly lower compared with the low, mild, and moderate groups (all P < 0.05). The global systolic strain rate (SRs) in the high group was −1.24 ± 0.24, and it was higher than those in the low, mild, and moderate groups (all P < 0.05). Salt intake was independently and positively correlated with global SRs, Tei index, and the parameters of left ventricular structure separately; negatively correlated with global SRe and SRa, left ventricular short axis shortening rate, left ventricular ejection fraction after adjusting for confounders (all P_adjusted < 0.001). Hayes process analyses demonstrated that the mediating effects of hsCRP on global SRe, SRa, and SRs; Tei index; and left ventricular remodeling index were −0.013 (95% CI: −0.015 to −0.010), −0.010 (−0.012 to −0.008), 0.008 (0.006–0.010), 0.005 (0.003–0.006), and 0.010 (0.009–0.012), respectively (all P_adjusted < 0.001).

Conclusion

Our data indicate that excess salt intake is independently associated with the impairment in myocardial viability and cardiac function, as well as myocardial remodeling. Chronic inflammation might play a mediating role in the association between high salt intake and cardiac function damage and myocardial remodeling.

Effects of Sodium Intake on Health and Performance in Endurance and Ultra-Endurance Sports

The majority of reviews on sports nutrition issues focus on macronutrients, often omitting or paying less attention to substances such as sodium. Through the literature, it is clear that there are no reviews that focus entirely on the effects of sodium and in particular on endurance sports. Sodium intake, both at high and low doses, has been found to be associated with health and performance issues in athletes. Besides, there have been theories that an electrolyte imbalance, specifically sodium, contributes to the development of muscle cramps (EAMC) and hyponatremia (EAH). For this reason, it is necessary to create this systematic review, in order to report extensively on the role of sodium consumption in the population and more specifically in endurance and ultra-endurance athletes, the relationship between the amount consumed and the occurrence of pathological disorders, the usefulness of simultaneous hydration and whether a disturbance of this substance leads to EAH and EAMC. As a method of data collection, this study focused on exploring literature from 2000–2021. The search was conducted through the research engines PubMed and Scopus. In order to reduce the health and performance effects in endurance athletes, simultaneous emphasis should be placed on both sodium and fluid intake.

Dietary sodium and health: How much is too much for those with orthostatic disorders?

High dietary salt (NaCl) increases blood pressure (BP) and can adversely impact multiple target organs including the vasculature, heart, kidneys, brain, autonomic nervous system, skin, eyes, and bone. However, patients with orthostatic disorders are told to increase their NaCl intake to help alleviate symptoms. While there is evidence to support the short-term benefits of increasing NaCl intake in these patients, there are few studies assessing the benefits and side effects of long-term high dietary NaCl. The evidence reviewed suggests that high NaCl can adversely impact multiple target organs, often independent of BP. However, few of these studies have been performed in patients with orthostatic disorders. We conclude that the recommendation to increase dietary NaCl in patients with orthostatic disorders should be done with care, keeping in mind the adverse impact on dietary NaCl in people without orthostatic disorders. Modest, rather than robust, increases in NaCl intake may be sufficient to alleviate symptoms but also minimize any long-term negative effects.

Impact of oats in the prevention/management of hypertension

Oats are a rich source of a soluble fibre, beta-glucan, phenolic compounds, as well as functional lipid and protein components that could potentially aid in preventing and managing hypertension. Processing techniques commonly used to manufacture oat based foods have been shown to improve its physiological efficacy. Hypertension is a common condition that is a risk factor for cardiovascular disease, a primary cause of mortality worldwide. Though exercise and pharmacological interventions are often used in the management of hypertension, diet is an incredibly important factor. One preclinical study and a handful of clinical studies have shown that oat components/products are effective in lowering blood pressure. However, research in this area is limited and more studies are needed to elucidate the anti-hypertensive potential of oats.

Perceptions and Feasibility of Actions Related to Sodium Reduction among Restaurant Owners and Cooks in Seongnam, South Korea: Comparison According to Stages of Behavioral Change

With the increase in meals eaten outside the home, sodium reduction in restaurant foods is essential for reducing sodium intake. This study aimed to assess the stages of behavioral change for reducing sodium and the differences in perceptions among restaurant staff by stage. Restaurant owners and cooks (n = 313) in Seongnam, South Korea were surveyed on their stage of behavioral change, practices, and perceptive factors related to sodium reduction in restaurant meals using a questionnaire. The proportion of behavioral change by stage was 20.4% in the maintenance and action (MA) stage, 32.3% in the preparation (P) stage, and 47.3% in the pre-preparation (PP) stage, which included contemplation and pre-contemplation stages. The items that represent differences among the groups were recognition of social environment for sodium reduction, practice of weighing condiments and measuring salinity, and feasibility of actions related to low-sodium cooking. Logistic regression analysis was used to estimate odds ratios for practice and perceptive factors by using stage of behavioral change as the independent variable. Factors associated with being in the MA stage were weighing condiments, measuring salinity, and high feasibility of actions related to low-sodium cooking. Recognition of sodium labeling and anticipation of better taste by reducing sodium increased the odds of being in the P stage rather than the PP stage. These results suggest that customized stepwise education and support are needed for the efficacy of restaurant-based sodium reduction programs.

Maillard-reacted peptides from glucosamine-induced glycation exhibit a pronounced salt taste-enhancing effect

Reducing salt intake, as one of the most cost-effective approaches, is congruent with improved population health. Grass carp skin collagen was subjected to enzymatic hydrolysis and ultrafiltration, followed by glucosamine-induced Maillard reaction to prepare Maillard-reacted peptides. Their color, free amino acid and peptide size distribution were analyzed, while UV and fluorescence spectroscopy were utilized to characterize the progress of Maillard reaction. The salt taste-enhancing effect of Maillard-reacted peptides was investigated via sensory analysis and electronic tongue. LC-MS/MS was employed to analyze the glycation sites of Maillard-reacted peptides. The results indicated that the degree of Maillard reaction was relatively low, and thermal degradation and crosslinking simultaneously occurred. Maillard-reacted peptides exhibited a significant salt taste-enhancing effect, which may be attributed to the glucosamine-induced glycation confirmed by LC-MS/MS analysis. The current study provides a theoretical basis for preparation of salt taste-enhancing peptides and their future application to reduce salt content of formulated foods.

MicroRNA-210-5p alleviates cardiac fibrosis via targeting transforming growth factor-beta type I receptor in rats on high sodium chloride (NaCl)-based diet

The present study was designed to explore whether high sodium chloride (NaCl)-based diet (HSD) caused cardiac fibrosis regardless of blood pressure in Sprague-Dawley (SD) rats, and to further determine the effects and the underlying mechanisms of microRNA (miR)-210-5p on HSD-induced cardiac fibrosis in rats or NaCl-induced cardiac fibroblast activation in neonatal rat cardiac fibroblasts (NRCFs). The SD rats received 8% HSD, and NRCFs were treated with NaCl. The levels of collagen I, alpha-smooth muscle actin (α-SMA) and transforming growth factor-beta 1 (TGF-β1) were increased in the heart of hypertension (HTN), hypertension-prone (HP) and hypertension-resistant (HR) rats on HSD in vivo. NaCl increased the levels of collagen I, α-SMA and TGF-β1 in NRCFs in vitro. The level of miR-210-5p was reduced in both NBD-induced rats' hearts and NaCl-treated NRCFs, which was consistent with the results of miR high-throughput sequencing in NRCFs. The HSD or NaCl-induced increases of collagen I, α-SMA and TGF-β1 were inhibited by miR-210-5p agomiR in vitro and in vivo, respectively. miR-210-5p antagomiR could mimic the pathological effects of NaCl in NRCFS. Bioinformatics analysis and luciferase reporter assays demonstrated that TGF-β type I receptor (TGFBR1) was a direct target gene of miR-210-5p. These results indicated that HSD resulted in cardiac fibrosis regardless of blood pressure. The upregulation of miR-210-5p could attenuate cardiac fibroblast activation in NRCFS via targeting TGFBR1. Thus, upregulating miR-210-5p might be a strategy for the treatment of cardiac fibrosis.

Salt supplementation in the management of orthostatic intolerance: Vasovagal syncope and postural orthostatic tachycardia syndrome

Salt supplementation is a common non-pharmacological approach to the management of recurrent orthostatic syncope or presyncope, particularly for patients with vasovagal syncope (VVS) or postural orthostatic tachycardia syndrome (POTS), although there is limited consensus on the optimal dosage, formulation and duration of treatment. Accordingly, we reviewed the evidence for the use of salt supplementation to reduce susceptibility to syncope or presyncope in patients with VVS and POTS. We found that short-term (~3 months) salt supplementation improves susceptibility to VVS and associated symptoms, with little effect on supine blood pressure. In patients with VVS, salt supplementation is associated with increases in plasma volume, and an increase in the time taken to provoke a syncopal event during orthostatic tolerance testing, with smaller orthostatic heart rate increases, enhanced peripheral vascular responses to orthostatic stress, and improved cerebral autoregulation. Responses were most pronounced in those with a baseline sodium excretion <170 mmol/day. Salt supplementation also improved symptoms, plasma volume, and orthostatic responses in patients with POTS. Salt supplementation should be considered for individuals with recurrent and troublesome episodes of VVS or POTS without cardiovascular comorbidities, particularly if their typical urinary sodium excretion is low, and their supine blood pressure is not elevated. The efficacy of the response, in terms of the improvement in subjective and objective markers of orthostatic intolerance, and any potential deleterious effect on supine blood pressure, should be routinely monitored in individuals on high salt regimes.

Nutritional Content of Sliced Bread Available in Quebec, Canada: Focus on Sodium and Fibre Content

Bread is a highly consumed food and an important source of nutrients in the diet of Canadians, underlining the need to improve its nutritional quality. The Food Quality Observatory (Observatory) aimed to evaluate the nutritional value of the sliced bread products available in Quebec (Canada), according to their grain type and main flour. Analyses included comparing the bread’s sodium content to Health Canada’s daily values (DV) and sodium voluntary targets, comparing the bread’s fibre content thresholds with the source of fibre mentioned, and assessing whether the main flour was associated with the nutrient content. The nutritional values of 294 sliced breads available in Quebec were merged with sales data (from October 2016 to October 2017), with 262 products successfully cross-referenced. The results showed that 64% of the breads purchased were ‘low’ in fibre (i.e., below 2 g per two slices), while 47% were ‘high’ in sodium (i.e., above 15% DV per two slices). Attention should be paid to 100% refined grain bread and to bread with refined flour as the main flour, since they are great sellers, while showing a less favourable nutrient content. This study shows that there is room for improvement in the nutritional content of Quebec’s bread offer, particularly regarding sodium and fibre content.

Sodium Content of Foods Sold in the Spanish Market. Results from the BADALI Project

High sodium/salt intake is a risk factor for Non-Communicable Diseases (NCDs). Excess sodium intake has been associated with high coronary heart disease, stroke and high blood pressure. The sodium daily intake is above the recommendations in the world as well as in Spain. Reducing salt content in processed foods and ready meals is one of the main strategies for reducing sodium intake. The aim of the present work is to characterise the presence of sodium in foods sold in the Spanish market. We also study a possible shift in sodium content in products over the last few years. For this purpose, 3897 products included in the BADALI food database were analysed, classified into 16 groups (G). We found that 93.3% of all foods displayed the sodium/salt content in the nutrition declaration. Meat—processed and derivatives (G8) had the highest mean and median values for sodium content, followed by snacks (G15) and sauces (G14). Only 12.7% of foods were sodium-free (≤5 mg/100 g or 100 mL), 32.4% had very low sodium (≤40 mg/100 g or 100 mL) and 48.2% were low in sodium (≤120 mg/100 g or 100 mL). On the contrary, 47.2% were high in sodium according to the Pan American Health Organisation Nutrient Profile Model (PAHO-NPM), while there were 31.9% according to the Chile-NPM. The agreement between the two NPMs was considered ‘substantial’ (κ = 0.67). When sodium content was compared over the years, no decrease was observed. This analysis was performed in the entire food population, by food group and in matched products. Therefore, more effort should be made by all parties involved in order to decrease the sodium/salt intake in the population.

Endogenous Taurine Downregulation Is Required for Renal Injury in Salt-Sensitive Hypertensive Rats via CBS/H2S Inhibition

Although taurine is known to exert an antihypertensive effect, it is unclear whether it is involved in the mechanism for hypertension-related target organ injury. To reveal the role of endogenous taurine in renal injury formation during salt-sensitive hypertension and clarify its mechanisms, both salt-sensitive Dahl rats and salt-resistant SS-13BN rats were fed a high-salt diet (8% NaCl) and given 2% taurine for 6 weeks. Rat systolic blood pressure (SBP) was measured by the tail-cuff method and artery catheterization. Kidney ultrastructure was observed under an electron microscope. Taurine content and mRNA and protein levels of taurine synthases, cysteine dioxygenase type 1 (CDO1) and cysteine sulfinic acid decarboxylase (CSAD), were decreased in Dahl rats fed a high-salt diet. However, taurine supplementation and the resulting increase in renal taurine content reduced the increased SBP and improved renal function and structural damage in high-salt diet-fed Dahl rats. In contrast, taurine did not affect SS-13BN SBP and renal function and structure. Taurine intervention increased the renal H₂S content and enhanced cystathionine-β-synthase (CBS) expression and activity in Dahl rats fed a high-salt diet. Taurine reduced the renin, angiotensin II, and aldosterone contents and the levels of oxidative stress indices in Dahl rat renal tissues but increased antioxidant capacity, antioxidant enzyme activity, and protein expression. However, taurine failed to achieve this effect in the renal tissue of SS-13BN rats fed a high-salt diet. Pretreatment with the CBS inhibitor HA or renal CBS knockdown inhibited H₂S generation and subsequently blocked the effect of taurine on renin, superoxide dismutase 1 (SOD1), and superoxide dismutase 2 (SOD2) levels in high-salt-stimulated Dahl renal slices. In conclusion, the downregulation of endogenous taurine production resulted in a decrease in the renal CBS/H₂S pathway. This decrease subsequently promoted renin-angiotensin-aldosterone system (RAAS) activation and oxidative stress in the kidney, ultimately contributing to renal injury in salt-sensitive Dahl rats.

Vascular contributions to cognitive impairment and dementia: the emerging role of 20-HETE

The accumulation of extracellular amyloid-β (Aβ) and intracellular hyperphosphorylated τ proteins in the brain are the hallmarks of Alzheimer's disease (AD). Much of the research into the pathogenesis of AD has focused on the amyloid or τ hypothesis. These hypotheses propose that Aβ or τ aggregation is the inciting event in AD that leads to downstream neurodegeneration, inflammation, brain atrophy and cognitive impairment. Multiple drugs have been developed and are effective in preventing the accumulation and/or clearing of Aβ or τ proteins. However, clinical trials examining these therapeutic agents have failed to show efficacy in preventing or slowing the progression of the disease. Thus, there is a need for fresh perspectives and the evaluation of alternative therapeutic targets in this field. Epidemiology studies have revealed significant overlap between cardiovascular and cerebrovascular risk factors such as hypertension, diabetes, atherosclerosis and stroke to the development of cognitive impairment. This strong correlation has given birth to a renewed focus on vascular contributions to AD and related dementias. However, few genes and mechanisms have been identified. 20-Hydroxyeicosatetraenoic acid (20-HETE) is a potent vasoconstrictor that plays a complex role in hypertension, autoregulation of cerebral blood flow and blood-brain barrier (BBB) integrity. Multiple human genome-wide association studies have linked mutations in the cytochrome P450 (CYP) 4A (CYP4A) genes that produce 20-HETE to hypertension and stroke. Most recently, genetic variants in the enzymes that produce 20-HETE have also been linked to AD in human population studies. This review examines the emerging role of 20-HETE in AD and related dementias.

The Combined Effect of Weaning Stress and Immune Activation during Pig Gestation on Serum Cytokine and Analyte Concentrations

Weaning stress can elicit changes in the metabolic, hormone and immune systems of pigs and interact with prolonged disruptions stemming from maternal immune activation (MIA) during gestation. The present study advances the characterization of the combined effects of weaning stress and MIA on blood chemistry, immune and hormone indicators that inform on the health of pigs. Three-week-old female and male offspring of control gilts or gilts infected with the porcine reproductive and respiratory syndrome virus were allocated to weaned or nursed groups. The anion gap and bilirubin profiles suggest that MIA enhances tolerance to the effects of weaning stress. Interleukin 1 beta and interleukin 2 were highest among weaned MIA females, and cortisol was higher among weaned relative to nursed pigs across sexes. Canonical discriminant analysis demonstrated that weaned and nursed pigs have distinct chemistry profiles, whereas MIA and control pigs have distinct cytokine profiles. The results from this study can guide management practices that recognize the effects of the interaction between MIA and weaning stress on the performance and health of pigs.

Dietary recommendations for prevention of atherosclerosis

This review aims at summarizing updated evidence on cardiovascular disease (CVD) risk associated with consumption of specific food items to substantiate dietary strategies for atherosclerosis prevention. A systematic search on PubMed was performed to identify meta-analyses of cohort studies and RCTs with CVD outcomes. The evidence is highly concordant in showing that, for the healthy adult population, low consumption of salt and foods of animal origin, and increased intake of plant-based foods-whole grains, fruits, vegetables, legumes, and nuts-are linked with reduced atherosclerosis risk. The same applies for the replacement of butter and other animal/tropical fats with olive oil and other unsaturated-fat-rich oil. Although the literature reviewed overall endorses scientific society dietary recommendations, some relevant novelties emerge. With regard to meat, new evidence differentiates processed and red meat-both associated with increased CVD risk-from poultry, showing a neutral relationship with CVD for moderate intakes. Moreover, the preferential use of low-fat dairies in the healthy population is not supported by recent data, since both full-fat and low-fat dairies, in moderate amounts and in the context of a balanced diet, are not associated with increased CVD risk; furthermore, small quantities of cheese and regular yogurt consumption are even linked with a protective effect. Among other animal protein sources, moderate fish consumption is also supported by the latest evidence, although there might be sustainability concerns. New data endorse the replacement of most high glycemic index (GI) foods with both whole grain and low GI cereal foods. As for beverages, low consumption not only of alcohol, but also of coffee and tea is associated with a reduced atherosclerosis risk while soft drinks show a direct relationship with CVD risk. This review provides evidence-based support for promoting appropriate food choices for atherosclerosis prevention in the general population.

Impact of Brazil Nut (Bertholletia excelsa, H.B.K.) Supplementation on Body Composition, Blood Pressure, and the Vascular Reactivity of Wistar Rats When Submitted to a Hypersodium Diet

Introdution: Endothelium integrity is a key that maintains vascular homeostasis but it can suffer irreversible damage by blood pressure changes, reflecting an imbalance in the maintenance of vascular homeostasis.Objective: The aim of this study was to investigate the impact of Brazil nut (Bertholletia excelsa, H.B.K.) (BN) supplementation (10% in chow, wt/wt) on the vascular reactivity of Wistar rats during chronic exposure to a sodium overload (1% in water).Methods: First, male Wistar rats were allocated into two groups: Control Group (CG) and the Hypersodic Group (HG) for 4 weeks. Afterward, the CG was divided into the Brazil Nut Group (BNG) and the HG Group into the Hypersodic Brazil Nut Group (HBNG) for a further 8 weeks, totaling 4 groups. Blood pressure was measured during the protocol. At the end of the protocol, the vascular reactivity procedure was performed. Glucose, lipid profile, lipid peroxidation, and platelet aggregation were analyzed in the serum. Body composition was determined by the carcass technique.Results: The groups that were supplemented with the BN chow presented less body mass gain and body fat mass, together with lower serum glucose levels. The HG Group presented an increase in blood pressure and a higher platelet aggregation, while the BN supplementation was able to blunt this effect. The HG Group also showed an increase in contractile response that was phenylephrine-induced and a decrease in maximum relaxation that was acetylcholine-induced when compared to the other groups.Conclusion: The BN supplementation was able to prevent an impaired vascular function in the early stages of arterial hypertension, while also improving body composition, serum glucose, and platelet aggregation.

Association between the Urinary Sodium to Potassium Ratio and Blood Pressure in Adults: A Systematic Review and Meta-Analysis

While sodium and potassium are individually important for blood pressure (BP) regulation, the relative contribution of sodium to potassium intake has not been sufficiently investigated. This study aimed to evaluate the association between urinary sodium to potassium ratio (UNa: K) and systolic and diastolic BP in adults. A systematic review (PROSPERO; CRD42016035296) was conducted and was reported according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Three scientific databases (MEDLINE, Scopus, Web of Science) were searched to March 2020 while reference lists of included articles were further hand-searched. Randomized controlled trials (RCT), cohort and cross-sectional studies that assessed 24-h urinary excretion in adults were included. Data from eligible studies were extracted and summarized. Random effects meta-analysis was conducted on RCT data to assess standardized mean differences (SMD) in systolic and diastolic BP according to 24-h UNa: K. Thirty-nine studies were included. Meta-analysis of 5 RCTs found a lower UNa: K ratio to be associated with a significantly greater reduction in systolic and diastolic BP compared with a higher UNa: K ratio [SMD: -1.09 (95% CI: -1.91, -0.28) mmHg and -1.42 (95% CI: -2.24, -0.59) mmHg, respectively]. Heterogeneity between RCTs was observed in systolic and diastolic BP (I2 = 97%, P < 0.0001 and I2 = 98%, P < 0.0001, respectively). The current body of evidence demonstrates that a lower 24-h UNa: K ratio is associated with lower BP in adults. Dietary strategies to achieve an increase in potassium while at the same time lowering sodium would be beneficial in lowering BP.

Impact of functional foods and nutraceuticals on high blood pressure with a special focus on meta-analysis: review from a public health perspective

In recent times many researchers are expressing immense interest in nutraceuticals and functional foods for combating various diseases or abnormal conditions, especially against hypertension (HT). Persistent HT is medically referred to as chronic high blood pressure (BP) and considered to be one of the major risk factors for the deadliest diseases including cardiovascular disease (CVD) and cerebrovascular diseases. Hence HT poses a serious socio-economic burden worldwide, particularly to developing countries. The current treatment strategy for HT includes standard anti-hypertensive drugs, which are associated with many adverse effects and lower drug adherence rates. Therefore, an alternative or complementary natural therapy (functional foods or nutraceuticals or dietary supplements) would be the alternate choice along with a modified lifestyle pattern that might help to manage or combat HT and its related complications. During this review, the author would like to shed light on the basic science behind HT including pathophysiology and the impact of dietary salt on HT and the impact of various functional foods or nutraceuticals against HT in humans (meta-analysis and systemic review). This contribution gives a better idea (public health perspective) for choosing the best functional foods/nutraceuticals for the prevention, management or delaying the onset of HT and its associated conditions along with modified lifestyle patterns and standard anti-hypertensive drugs.

Effects of High Salt Intake on Detrusor Muscle Contraction in Dahl Salt-Sensitive Rats

High salt intake has been reported as a risk factor for urinary storage symptoms. However, the association between high salt intake and detrusor muscle contraction is not clear. Therefore, we investigated the effects of high salt intake on the components of detrusor muscle contraction in rats. Six-week-old male Dahl salt-resistant (DR; n = 5) and Dahl salt-sensitive (DS; n = 5) rats were fed a high salt (8% NaCl) diet for one week. The contractile responses of the detrusor muscle to the cumulative administration of carbachol and electrical field stimulation (EFS) with and without suramin and atropine were evaluated via isometric tension study. The concentration-response curves of carbachol were shifted more to the left in the DS group than those in the DR group. Contractile responses to EFS were more enhanced in the DS group than those in the DR group (p < 0.05). Cholinergic component-induced responses were more enhanced in the DS group than those in the DR group (p < 0.05). High salt intake might cause urinary storage symptoms via abnormalities in detrusor muscle contraction and the enhancement of cholinergic signals. Excessive salt intake should be avoided to preserve bladder function.

Idiopathic Osteoporosis and Nephrolithiasis: Two Sides of the Same Coin?

Idiopathic osteoporosis and nephrolithiasis are formidable health problems showing a progressive increase in their incidence and prevalence in the last decades. These temporal trends were observed in both pediatric and adult populations worldwide. Epidemiological and experimental studies indicate that both disorders show several common pathogenic environmental and genetic factors. In this review, we analyzed the clinical characteristics common to the two disorders and the state-of-the-art knowledge regarding the genetic predisposition and the environmental factors recognized as triggers in adult and pediatric ages. As a result of this work, we propose to consider idiopathic nephrolithiasis and osteoporosis as two possible expressions of a unique clinical syndrome. Accordingly, the clinical approach to both disorders should be modified in order to program an efficient primary and secondary prevention strategy.

High dietary sodium augments vascular tone and attenuates low-flow mediated constriction in salt-resistant adults

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.