Sodium and Potassium and the Pathogenesis of Hypertension

The Relationship between Low-Sodium Salt Intake and Both Blood Pressure Level and Hypertension in Chinese Residents

Compared to common salt, low-sodium salt can reduce blood pressure to varying degrees. However, the exact dosage relationship remains unclear. We aimed to investigate the dose-response relationships between low-sodium salt intake and systolic blood pressure (SBP) and diastolic blood pressure (DBP), as well as the risk of hypertension, and to determine the optimal range for low-sodium salt intake. We investigated the basic characteristics and dietary profile of 350 individuals who consumed low-sodium salt. The samples were divided into three groups according to the 33.3rd and 66.6th percentiles of low-sodium salt intake in condiments (Q1: <4.72 g/d, Q2: ≥4.72 g/d, and <6.88 g/d, and Q3: ≥6.88 g/d). The restricted cubic spline results indicated that low-sodium salt intake decreased linearly with SBP and DBP, while low-sodium intake demonstrated a non-linear, L-shaped relationship with the risk of hypertension, with a safe range of 5.81 g to 7.66 g. The multiple linear regression analysis revealed that compared with group Q1, the DBP in group Q2 decreased by 2.843 mmHg (95%CI: -5.552, -0.133), and the SBP in group Q3 decreased by 4.997 mmHg (95%CI: -9.136, -0.858). Exploratory subgroup analyses indicated that low-sodium salt intake had a significant impact on reducing SBP in males, DBP in females, SBP in rural populations, and DBP in urban populations. The intake of low-sodium salt adheres to the principle of moderation, with 5.81-7.66 g potentially serving as a pivotal threshold.

Spot urinary sodium-to-potassium ratio is associated with blood pressure levels in healthy adolescents: the Wakayama Study

The spot urinary sodium-to-potassium (Na/K) ratio is a simple measure of salt loading and has been shown to be associated with elevated blood pressure (BP) in middle-aged and older adults. This study aimed to evaluate the association between the spot urinary Na/K ratio and BP in 457 healthy adolescents aged 12-15 years in a school-based setting. The mean urinary Na/K ratio was 4.99 ± 2.76, and no significant difference was found between the boys and girls. When the participants were stratified based on urinary Na/K ratio quartile, age- and sex-adjusted systolic and diastolic BP gradually increased as Na/K ratio increased (systolic BP: 106.1, 106.9, 108.2, and 111.5 mmHg, Ptrend < 0.001; diastolic BP: 62.0, 62.4, 63.1, 64.3 mmHg, Ptrend = 0.022). The systolic and diastolic BP were more closely associated with urinary Na/K ratio than with Na and K levels, as well as estimated daily salt intake. In the multiple regression analysis, the urinary Na/K ratio was significantly associated with systolic BP (β = 0.144, P < 0.001) and diastolic BP (β = 0.114, P = 0.015) independent of potential confounding factors. An additional subgroup analysis revealed that the BP of the group with both high salt intake (≥8.5 g/day) and high Na/K ratio (≥6.60) was significantly higher than that of the group with high salt intake alone (systolic BP, 115.0 vs. 109.1 mmHg, P < 0.001; diastolic BP, 66.0 vs. 62.5 mmHg, P = 0.017). These results suggest that the urinary Na/K ratio is associated with BP levels in healthy adolescents and may be useful for assessing salt loading and its effects on BP elevation.

Impact of clinico-biochemical variations on the etiopathogenesis of cataract: a case-control study

Purpose:

Cataract is a major cause of blindness worldwide with a greater prevalence in developing countries like India. Owing to speculations about the relationship of various biochemical markers and cataract formation this case-control study was designed with the aim to know the impact of serum blood sugar, serum electrolytes and serum calcium on the etiopathogenesis of cataract in Kashmiri population.

Methods:

A total of 300 cases diagnosed with cataract and 360 healthy controls were taken for the study. Serum of all the cases and controls was analyzed for blood sugar and calcium using spectrometric techniques. Sodium and potassium were analyzed using Ion-Selective Electrode technology. All the investigations were done on ABBOTT c4000 fully automatic clinical chemistry analyzer.

Results:

Most of the patients in our study were ≥50 years of age having posterior subcapsular cataract. The mean levels of serum fasting blood sugar (mg/dL), serum sodium (mmol/L), serum potassium (mmol/L) and serum calcium (mg/dL) were 99.4 ± 7.7; 140.4 ± 2.5; 4.2 ± 0.5; and 8.9 ± 0.5, respectively, in cases compared to 107.7 ± 12.3; 142.9 ± 5.0; 3.8 ± 0.5; and 8.3 ± 1.7, respectively, in healthy controls. A significantly higher number of cataract cases had elevated serum glucose and sodium levels, low serum potassium and calcium levels compared to healthy controls.

Conclusions:

Hyperglycemia, hypernatremia, hypokalemia and hypocalcemia can independently increase the patients’ risk to cataracts. Corrections in these biochemical parameters may reduce cataract incidence.

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.

Early Contributors to Healthy Arterial Aging Versus Premature Atherosclerosis in Young Adults: The Bogalusa Heart Study

Background

Early identification of healthy arterial aging versus premature atherosclerosis is important for optimal atherosclerotic cardiovascular disease risk stratification and prevention. We sought to identify predictors for the long‐term absence of carotid plaque among young adults.

Methods and Results

We included 508 participants from the Bogalusa Heart Study without clinical atherosclerotic cardiovascular disease who were free of carotid plaque at baseline (2001–2002) and underwent ultrasound imaging at follow‐up (2013–2016). Modified Poisson regression estimated the persistent absence of plaque over 12.8 years. Participants were on average age 36.2 years at baseline, 64% were women, and 29% were Black. Although nearly all participants (97%) had a 10‐year atherosclerotic cardiovascular disease risk <7.5%, there were 162 people (32%) who developed premature atherosclerosis. Aside from younger age (risk ratio [RR], 1.21; 95% CI, 1.07–1.36, per 10 years) and a total cholesterol/high‐density lipoprotein cholesterol ratio <3.5 (RR, 1.15; 95% CI, 1.01–1.30), normal values of traditional risk factors did not predict long‐term absence of plaque. Independent from traditional markers including glomerular filtration rate, serum calcium‐phosphate product (RR, 1.07; 95% CI, 1.01–1.14, per 1‐SD lower), phosphate (RR, 1.15; 95% CI, 1.03–1.29, per 1 mg/dL lower), and dietary sodium <2300 mg/day (RR, 1.20; 95% CI, 1.02–1.41) were significantly associated with the non‐development of plaque.

Conclusions

Nearly one third of young adults with a low burden of traditional risk factors developed premature atherosclerosis. Beyond younger age and an ideal lipoprotein profile, lower calcium‐phosphate homeostasis and low sodium intake were associated with long‐term absence of carotid plaque. These results suggest that dietary and intrinsic minerals are early contributors to the development of arterial aging phenotypes.

Advances in Genomics Research of Blood Pressure Responses to Dietary Sodium and Potassium Intakes

More than half of US adults have hypertension by 40 years of age and a subsequent increase in atherosclerotic cardiovascular disease risk. Dietary sodium and potassium are intricately linked to the pathophysiology of hypertension. However, blood pressure responses to dietary sodium and potassium, phenomena known as salt and potassium sensitivity of blood pressure, respectively, are heterogenous and normally distributed in the general population. Like blood pressure, salt and potassium sensitivity are complex phenotypes, and previous research has shown that up to 75% of individuals experience a blood pressure change in response to such dietary minerals. Previous research has also implicated both high salt sensitivity and low salt sensitivity (or salt resistance) of blood pressure to an increased risk of hypertension and potentially atherosclerotic cardiovascular disease risk. Given the clinical challenges required to accurately measure the sodium and potassium response phenotypes, genomic characterization of these traits has become of interest for hypertension prevention initiatives on both the individual and population levels. Here, we review advances in human genomics research of blood pressure responses to dietary sodium and potassium by focusing on 3 main areas, including the phenotypic characterization of salt sensitivity and resistance, clinical challenges in diagnosing such phenotypes, and the genomic mechanisms that may help to explain salt and potassium sensitivity and resistance. Through this process, we hope to further underline the value of leveraging genomics and broader multiomics for characterizing the blood pressure response to sodium and potassium to improve precision in lifestyle approaches for primordial and primary atherosclerotic cardiovascular disease prevention.

The Correlation Between Urinary Sodium Excretion and Blood Pressure in Hospitalized Adult Patients with Hypertension

INTRODUCTION

This study was designed to understand the baseline salt intake of adult patients with hypertension in Shanxi Province, and to analyze the correlation between urinary sodium excretion and blood pressure.

METHODS

From June 2018 to December 2019, 16 hospitals with regional representativeness and experimental conditions in Shanxi Province were selected, and 643 eligible adult inpatients with primary hypertension were enrolled from these hospitals. The ages of patients ranged from 18 to 80 years. A 24-h ambulatory blood pressure monitoring was performed, and morning urine sodium concentration and 24-h urine sodium excretion were measured. The correlation between urinary sodium excretion and blood pressure in adult patients with hypertension was analyzed.

RESULTS

The baseline salt intake of the adult patient participants with hypertension in Shanxi Province was 11.51 g/day. The average 24-h urinary sodium excretion of all observed subjects was 191.90 ± 98.18 mmol. The 24-h urinary sodium excretion and morning urinary sodium concentration were significantly positively correlated with systolic and diastolic blood pressure following adjustment of confounding factors, including gender, age, body weight, and smoking.

CONCLUSION

The morning urine sodium concentration and 24-h urine sodium excretion were significantly positively correlated with blood pressure. High sodium excretion may be a risk factor for rhythm abnormalities in non-dipper pattern blood pressure. The control of urinary sodium concentration can thus be an important strategy for regulating abnormal blood pressure rhythm.

Whole body potassium as a biomarker for potassium uptake using a mouse model

Potassium is known for its effect on modifiable chronic diseases like hypertension, cardiac disease, diabetes (type-2), and bone health. In this study, a new method, neutron generator based neutron activation analysis (NAA), was utilized to measure potassium (K) in mouse carcasses. A DD110 neutron generator based NAA assembly was used for irradiation.Thirty-two postmortem mice (n= 16 males and 16 females, average weight \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$22.02\pm 1.3$$\end{document}22.02±1.3 and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$17.9\pm 1.1$$\end{document}17.9±1.1 g) were employed for this study. Soft-tissue equivalent mouse phantoms were prepared for the calibration. All mice were irradiated for 10 minutes, and the gamma spectrum with 42K was collected using a high efficiency, high purity germanium (HPGe) detector. A lead shielding assembly was designed and developed around the HPGe detector to obtain an improved detection limit. Each mouse sample was irradiated and measured twice to reduce uncertainty. The average potassium concentration was found to be significantly higher in males \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$(2846 \pm 525 \upmu g/g)$$\end{document}(2846±525μg/g) compared to females \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$(2116.2 \pm 432 \upmu g/g)$$\end{document}(2116.2±432μg/g). We also observed a significant correlation between potassium concentration and the weight of the mice. The detection limit for potassium quantification with the NAA system was 46 ppm. The radiation dose to the mouse was approximately 56 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${ \pm 1.6 }$$\end{document}±1.6 mSv for 10-min irradiation. In conclusion, this method is suitable for estimating individual potassium concentration in small animals. The direct evaluation of total body potassium in small animals provides a new way to estimate potassium uptake in animal models. This method can be adapted later to quantify potassium in the human hand and small animals in vivo. When used in vivo, it is also expected to be a valuable tool for longitudinal assessment, kinetics, and health outcomes.

The ratio potassium-to-magnesium intake and high blood pressure

BACKGROUND

To analyse whether the weight ratio of potassium-to-magnesium intake is associated with incident high blood pressure, in otherwise healthy individuals.

MATERIALS AND METHODS

A total of 529 healthy individuals were enrolled in a cross-sectional study and allocated into following groups: group 1) potassium and magnesium intake within Recommended Dietary Allowance; group 2) magnesium intake as recommended and potassium intake below of recommended dietary allowance; group 3) potassium intake as recommended and magnesium intake below of recommended dietary allowance; and group 4) magnesium and potassium intake below recommended dietary allowance. Groups in study were matched by sodium and calcium intake. A "24 hours recall" questionnaire was used to register all intakes of food and drinks for two consecutive days. Multiple logistic regression analysis adjusted by sex, waist circumference, and triglycerides levels was used to compute the odds ratio between intakes of magnesium and potassium with the high blood pressure.

RESULTS

High blood pressure was identified in 155 (29.3%) individuals. There were no statistical significant differences by obesity and overweight between the groups. As compared with individuals in the group 1, the potassium-to-magnesium ratio (odds ratio 0.88; 95%CI 0.85-0.93) but not the isolated magnesium and potassium intake per se, was inversely associated to high blood pressure in the subjects of group 4; individuals in the groups 2 and 3 showed no association.

CONCLUSIONS

Our results suggest that, in healthy individuals with magnesium and potassium intake below recommended dietary allowance, the high potassium-to-magnesium ratio is inversely associated with incident high blood pressure.

School meals' centesimal and mineral composition and their nutritional value for Brazilian children

The assessment of meals served under the Brazilian National School Meal Program (PNAE) is an important tool to verify its adequacy to the proposed parameters and the nutritional needs of school-aged children. The aim of this study was to evaluate the centesimal and mineral composition of the meals offered by the program and adequacy to the nutritional recommendations in three municipalities of the state of Bahia, Brazil. Centesimal composition of meals was determined according to the reference guidelines and mineral composition was analyzed by atomic absorption spectrometry. Non-parametric analysis of variance was used to test the differences of the medians among the municipalities and Student-t test to compare the means between the two sampling periods. There were inadequacies in the carbohydrate, lipid and protein contents, and none of the municipalities reached the recommendation of 20%. Mineral concentration, especially Fe, Se, Cu and K were much lower than expected. Sodium levels were three-folds higher than the recommended, being worrisome due to higher risk of elevated blood pressure. There were inadequacies with regard to the PNAE guidelines, and there is a need to reevaluate the meals that are being offered to better meet childreńs needs and to form healthy habits from childhood.

Adding Salt to Meals as a Risk Factor of Type 2 Diabetes Mellitus: A Case-Control Study

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is thought to arise from the complex interplay between genetic and environmental factors. It is important to identify modifiable risk factors that may help to reduce the risk of diabetes. Data on salt intake and the risk of type 2 diabetes are limited. The aim of this study was to assess the relationship between adding salt to prepared meals and the risk of type 2 diabetes.

METHODS

In a case-control study, we included 234 cases, all of whom were patients aged 35-86 years with a newly confirmed diagnosis of T2DM, and 468 controls that were free of the disease. Cases and controls (ratio 1:2) were matched by gender and age (±5 years). A questionnaire was used to collect information on possible risk factors for diabetes. Adding salt to prepared meals was assessed according to: Never, when there was not enough, or almost every time without tasting. The odds ratios (OR), and 95% confidence intervals (CI) for type 2 diabetes was calculated using a conditional logistic regression.

RESULTS

The cases had a higher body mass index and a significantly lower education level compared to the controls. Variables such as waist circumference, body mass index, eating speed, smoking, family history of diabetes, arterial hypertension, plasma triglycerides, educational level, occupational status, morning exercise, marital status, daily urine sodium excretion, and daily energy intake were retained in the models as confounders. After adjusting for possible confounders, an approximately two-fold increased risk of type 2 diabetes was determined in subjects who add salt to prepared meals when "it is not enough" or "almost every time without tasting" (1.82; 95% CI 1.19-2.78; p = 0.006) compared with never adding salt.

CONCLUSION

Presented data suggest the possible relationship between additional adding of salt to prepared meals and an increased risk of type 2 diabetes.

Modulation of the vascular endothelium functioning by dietary components, the role of epigenetics

Rather than being a passive barrier between circulating blood and smooth muscle cells and the underlying tissues, the endothelium is a fundamental functional component of the vasculature, and could be viewed as the largest human endocrine gland/organ, secreting multiple pro-/antiangiogenic factors, cytokines and low-molecular-weight mediators controlling the vascular tone. The location of endothelium, at the interface between the circulation and the tissues, makes this epithelial layer particularly exposed to physical and chemical cues coming from the bloodstream. In response to such stimuli, the endothelium modulates its morphology and functions to maintain vascular homeostasis. Dietary components significantly affect the proper functioning of the endothelium. High-calories and high-fat western diets, in the long term, cause endothelial dysfunction, which is a major contributor to the development of the metabolic syndrome and its pathological consequences, including atherosclerosis, diabetes, and hypertension. On the contrary, plant-derived antioxidant molecules and polyphenols have been shown to exert beneficial effects on endothelial function. Extensive research in the last decade has clearly shown the close relationship between food intake, dietary habits, and gene expression, which is driven by the action of macro- and micronutrients on chromatin regulation. Nutrient-induced chromatin epigenetic modifications via DNA methylation and histone post-translational modifications, especially in the context of the western diet, significantly contribute to the dysregulation of endothelial functioning. Here, we review the current understanding on how dietary components (macronutrients, antioxidants), acting on epigenetic mechanisms, regulate endothelial physiology, and physiopathology. © 2016 BioFactors, 43(1):5-16, 2017.

The Hyponatremia Epidemic: A Frontier Too Far?

Hyponatremia is the most common electrolyte abnormality and is often neglected, especially in elderly and seemingly terminal patients. Hyponatremia can be asymptomatic or can cause symptoms ranging from nausea and lethargy to convulsions and coma. This condition has become increasingly common over time with a similar time course to the increase in adoption of low salt diets. The popularization of low salt may not be justified in people with normal kidney function in whom the compatible statistically based evidence that salt causes hypertension has been challenged by experimental evidence to the contrary.

Association between 24h Urinary Sodium and Potassium Excretion and Estimated Glomerular Filtration Rate (eGFR) Decline or Death in Patients with Diabetes Mellitus and eGFR More than 30 ml/min/1.73m2

Background

Data regarding the association between 24h urinary sodium and potassium excretion with kidney outcomes in patients with diabetes mellitus is currently scarce.

Methods

We conducted a single-center, retrospective cohort study in which 1230 patients with diabetes who had undergone a 24h urinary sodium and potassium excretion test were analyzed. Patients with incomplete urine collection were excluded based on 24h urinary creatinine excretion. Outcomes were the composite of a 30% decline in eGFR or death. Multivariate cox regression analysis was used to investigate the association between urinary sodium and potassium excretion and outcomes.

Results

With a mean follow up period of 5.47 years, 130 patients reached the outcomes (30% decline in eGFR: 124, death: 6). Mean (SD) eGFR and 24h urinary sodium and potassium excretion at baseline were 78.6 (19.5) ml/min/1.73m², 4.50 (1.64) g/day, and 2.14 (0.77) g/day. Compared with sodium excretion < 3.0 g/day, no significant change in risk of outcomes was observed with increased increments of 1.0 g/day. Compared with potassium excretion of < 1.5 g/day, 2.0–2.5 g/day, and 2.5–3.0 g/day were significantly associated with a lower risk of outcomes (hazard ratio [HR], 0.49 and 0.44; 95% confidence interval [CI], 0.28 to 0.84 and 0.22 to 0.87).

Conclusions

24h urinary sodium excretion was not significantly associated with a risk of 30% decline in eGFR or death in patients with diabetes. However, an increased risk of 30% decline in eGFR or death was significantly associated with 24h urinary potassium excretion < 1.5 g/day than with 2.0–2.5 g/day and 2.5–3.0 g/day.

High-dose consumption of NaCl resulted in severe degradation of lipoproteins associated with hyperlipidemia, hyperglycemia, and infertility via impairment of testicular spermatogenesis

Although the effect of NaCl on serum lipid levels and hypertension is well known, the detailed mechanism of lipoprotein metabolism still remains unclear. To study the physiological effects of high salt consumption on lipoprotein metabolism, NaCl was administered to human cells and zebrafish. Wildtype zebrafish (10-week old) were fed 10% NaCl (wt/wt) in tetrabit diet with or without 4% cholesterol (wt/wt) for 21 weeks. Treatment with NaCl accelerated oxidation and glycation of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) as well as induced proteolytic degradation and aggregation. NaCl treatment also exacerbated phagocytosis of oxLDL into macrophage as well as cytotoxicity. The consumption of high salt diet (HSD, final 5% or 10% in diet, wt/wt) supplemented with or without 4% cholesterol for 21 weeks resulted in a remarkable elevation of serum cholesterol, triglyceride, glucose, and hepatic inflammation levels in zebrafish with significant weight loss. Fertility based on egg production was reduced by up to 45% in the HSD group. However, embryonic survivability after hatching was significantly lowered to less than 55%, whereas the control group showed 87% survival. The HSD group showed abnormal testicular histology as well as spermatogenic defects, especially upon the consumption of HCD. These results suggest that hyperlipidemia and high salt consumption have an additive effect on male fertility impairment. High salt consumption exacerbates hyperlipidemia, inflammation, spermatogenic defects, and infertility via a modification of lipoproteins.

Low Response of Renin-Angiotensin System to Sodium Intake Intervention in Chinese Hypertensive Patients

The interactions of sodium balance and response of renin-angiotensin-aldosterone system are important for maintaining the hemodynamic stability in physiological conditions. However, the influence of short-term sodium intake intervention in the response of renin-angiotensin system (RAS) on hypertensive patients is still unclear. Thus, we conducted a clinical trial to investigate the effects of short-term sodium intake intervention on the response of RAS in hypertensive patients.One hundred twenty-five primary Chinese hypertensive patients were divided into high, moderate, and low sodium groups by 24-hour urinary sodium excretion (UNa). All the patients received a 10-day dietary sodium intake intervention with standardized sodium (173.91mmol/day) and potassium (61.53mmol/day). Blood pressure, urinary sodium, urinary potassium, plasma sodium, potassium, creatinine, the levels of plasma renin activity, plasma angiotensin II concentrations (AT-II), and plasma aldosterone concentrations were detected before and after the intervention.Before the intervention, no differences were found in blood pressure and RAS among 3 groups. After standardized dietary sodium intake intervention, both UNa excretion and systolic pressure decreased in high-sodium group, while they increased in moderate and low-sodium groups. Intriguingly, there were no changes in the levels of plasma renin activity, AT-II, and plasma aldosterone concentrations among 3 groups during the intervention.The present study demonstrated that the influenced sodium excretion and blood pressure by short-term sodium intake intervention were independent of RAS quick response in Chinese hypertensive patients.

Effect of fruits and vegetables on metabolic syndrome: a systematic review and meta-analysis of randomized controlled trials

Evidence regarding the effect of fruit and vegetable consumption on metabolic syndrome remains inconclusive. Using MEDLINE, EMBASE, and Cochrane, we searched for relevant studies published before 10 December 2013. Of the 383 articles identified, eight randomized controlled trials with 396 participants (205 in intervention groups and 191 in control groups) were included in the final analyses. Fruit and vegetable intake was associated with a reduction in diastolic blood pressure (standardized mean difference: -0.29; 95% confidence interval: -0.57 to -0.02; p = 0.04); however, such intake did not affect waist circumference, systolic blood pressure, fasting glucose, high-density lipoprotein cholesterol, and triglyceride levels in metabolic syndrome patients. In a subgroup analysis, there were no statistically significant differences found according to the intervention period and provision type. Our results suggest an inverse association between fruit and vegetable consumption and diastolic blood pressure in metabolic syndrome patients.

Meta-analysis of prospective studies on the effects of nut consumption on hypertension and type 2 diabetes mellitus

BACKGROUND

Inconclusive reports have been published on the consumption of nuts and the risk of hypertension and type 2 diabetes mellitus (T2DM). We performed a meta-analysis of prospective studies to assess the effects of nut consumption on hypertension and T2DM risks.

METHODS

A PUBMED and EMBASE database search was performed. Summary relative risks (SRRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Q and I2 statistics were used to examine between-study heterogeneity.

RESULTS

A total of eight articles with nine prospective cohort studies (three hypertension studies and six T2DM studies) were selected. Using random effects models, we found that compared with never/rare consumers of nuts, those consuming >2 servings per week had an 8% lower risk of hypertension (SRR = 0.92, 95% CI: 0.87-0.97, P(heterogeneity)  = 0.590, I2  = 0%), while consumption of nuts at one serving per week had similar risk (SRR = 0.97, 95% CI: 0.83-1.13). In addition, nuts consumption was not associated with risk of T2DM (SRRs = 0.98, 95% CI: 0.84-1.15; P(heterogeneity)  = 0.008, I2  = 67.7%) on the basis of the highest versus lowest analysis. This null association was also shown in the dose-response analysis.

CONCLUSION

Findings from this meta-analysis indicate that consumption of nuts (>2 servings/week) may be inversely associated with hypertension risk, but not with T2DM risk.

Molecular targets of antihypertensive peptides: understanding the mechanisms of action based on the pathophysiology of hypertension

There is growing interest in using functional foods or nutraceuticals for the prevention and treatment of hypertension or high blood pressure. Although numerous preventive and therapeutic pharmacological interventions are available on the market, unfortunately, many patients still suffer from poorly controlled hypertension. Furthermore, most pharmacological drugs, such as inhibitors of angiotensin-I converting enzyme (ACE), are often associated with significant adverse effects. Many bioactive food compounds have been characterized over the past decades that may contribute to the management of hypertension; for example, bioactive peptides derived from various food proteins with antihypertensive properties have gained a great deal of attention. Some of these peptides have exhibited potent in vivo antihypertensive activity in both animal models and human clinical trials. This review provides an overview about the complex pathophysiology of hypertension and demonstrates the potential roles of food derived bioactive peptides as viable interventions targeting specific pathways involved in this disease process. This review offers a comprehensive guide for understanding and utilizing the molecular mechanisms of antihypertensive actions of food protein derived peptides.

Interactive contribution of serine/threonine kinase 39 gene multiple polymorphisms to hypertension among northeastern Han Chinese

Serine/threonine kinase 39 (STK39) gene has been reported to be a hypertension-susceptibility gene by a recent genome-wide association study in Western populations. To validate this finding in Chinese, we focused on five well-characterized common polymorphisms in STK39 gene to examine their potential association with hypertension in a large northeastern Han population. This is a hospital-based case-control study involving 1009 hypertensive patients and 756 normotensive controls. Data were analyzed by the Haplo.Stats and multifactor dimensionality reduction (MDR) softwares. The genotype and allele distributions of rs6749447, rs3754777 and rs6433027 differed significantly between patients and controls (P < 0.001) even after the Bonferroni correction. The majority of derived haplotypes also showed remarkable differences between the two groups (P ≤ 0.001). As indicated by MDR analysis, a three-locus model including rs6749447, rs35929607 and rs3754777 was selected as the overall best with a larger testing accuracy of 0.7309 and a maximum cross-validation consistency of 10 (P < 0.001). The utility of this model was reinforced by a Logistic regression analysis. Taken together, our findings suggest the potential interactive role of STK39 gene multiple polymorphisms in the development of hypertension among northeastern Han Chinese.

The contributory role of angiotensin receptor-like 1 gene multiple polymorphisms in hypertension among northeastern Han Chinese

Background and Objective

Via direct sequencing, we have recently identified six common polymorphisms in angiotensin receptor-like 1 (AGTRL1) gene, and found only two polymorphisms were significantly associated with hypertension in a family-based analysis on 1,015 southern Han Chinese. Extending our previous work and considering the ubiquity of epistasis in determining disease susceptibility, we, in this study, sought to explore the potential interaction of AGTRL1 gene six polymorphisms with hypertension in a large northeastern Han Chinese population.

Methods and Results

This was a case-control study involving 1,009 sporadic hypertensive patients and 756 normotensive controls. Data were analyzed by Haplo.Stats and multifactor dimensionality reduction (MDR) softwares. There were no deviations from Hardy-Weinberg equilibrium for all polymorphisms. The genotypes and alleles of rs7119675 and rs11544374 differed significantly between the two groups (P<0.0005), even after the Bonferroni correction. Under three genetic models, significant association was consistently observed for rs7119675 and rs11544374, and this association was independent of confounding factors. Taking rs7119375 as an example, the odds of having hypertension was 2.46 (95% confidence interval (95% CI): 2.06–2.94), 2.82 (95% CI: 2.29–3.46) and 3.97 (95% CI: 2.37–6.64) under additive, dominant and recessive models (P<0.001), respectively, whereas the adjusted risk estimates were slightly attenuated but still significant. The frequencies of most derived haplotypes differed significantly between patients and controls. Haplotype-phenotype analyses indicated marginal association for triglyceride (P_Sim = 0.011) and total cholesterol (P_Sim = 0.025) in patients and for triglyceride in controls (P_Sim = 0.023). The overall best MDR model included rs11544374, rs7119375 and rs948847 with the maximal testing accuracy of 0.737 and cross-validation consistency of 10 out of 10 (P<0.0001). Further interaction entropy graph suggested that the interaction of rs7119375 with rs11544374 and rs948847 was strongly antagonized.

Conclusions

Our findings demonstrate that AGTRL1 genetic polymorphisms might contribute to the development of hypertension independently and/or through complex interaction.

RETRACTED: Nut consumption with risk of hypertension and type 2 diabetes mellitus: A meta-analysis of prospective cohort studies

Background

The consumption of nuts was reported to be associated with risk of hypertension and type 2 diabetes mellitus (T2DM), but the results were inconclusive. The aim of this study was to systematically examine longitudinal studies investigating nut intake in relation to risk of hypertension and T2DM.

Methods

A systematic search of the PubMed and EMBASE databases to 31 March 2013 was performed. Reference lists of retrieved articles were also screened. Summary relative risks (SRRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Q and I2 statistics were used to examine between-study heterogeneity.

Results

A total of nine prospective cohort studies (three for hypertension and six for T2DM) were identified. Using random effects models, we found that based on the highest vs lowest analysis, nut consumption were inversely associated with risk of hypertension (SRR = 0.84, 95% CI: 0.76–0.93, pheterogeneity = 0.831, I2 = 0%). Dose-response analyses indicated that nut consumption at more than two servings/wk, but not ne serving/wk, had a preventative role in the hypertension. In addition, nut consumption was not associated with risk of T2DM (SRRs = 0.98, 95% CI: 0.84–1.15; pheterogeneity = 0.008, I2 = 67.7%) on the basis of the highest vs lowest analysis. This null association was also shown in the dose-response analysis.

Conclusion

In our meta-analysis, nut consumption is found to be inversely associated with hypertension risk but is not associated with the risk of T2DM.