Potassium in Hypertension and Cardiovascular Disease

Potassium homeostasis - Physiology and pharmacology in a clinical context

Membrane voltage controls the function of excitable cells and is mainly a consequence of the ratio between the extra- and intracellular potassium concentration. Potassium homeostasis is safeguarded by balancing the extra-/intracellular distribution and systemic elimination of potassium to the dietary potassium intake. These processes adjust the plasma potassium concentration between 3.5 and 4.5 mmol/L. Several genetic and acquired diseases but also pharmacological interventions cause dyskalemias that are associated with increased morbidity and mortality. The thresholds at which serum K+ not only associates but also causes increased mortality are hotly debated. We discuss physiologic, pathophysiologic, and pharmacologic aspects of potassium regulation and provide informative case vignettes. Our aim is to help clinicians, epidemiologists, and pharmacologists to understand the complexity of the potassium homeostasis in health and disease and to initiate appropriate treatment strategies in dyskalemic patients.

Soilless Cultivated Halophyte Plants: Volatile, Nutritional, Phytochemical, and Biological Differences

The use of halophyte plants appears as a potential solution for degraded soil, food safety, freshwater scarcity, and coastal area utilization. These plants have been considered an alternative crop soilless agriculture for sustainable use of natural resources. There are few studies carried out with cultivated halophytes using a soilless cultivation system (SCS) that report their nutraceutical value, as well as their benefits on human health. The objective of this study was to evaluate and correlate the nutritional composition, volatile profile, phytochemical content, and biological activities of seven halophyte species cultivated using a SCS (Disphyma crassifolium L., Crithmum maritimum L., Inula crithmoides L., Mesembryanthemum crystallinum L., Mesembryanthemum nodiflorum L., Salicornia ramosissima J. Woods, and Sarcocornia fruticosa (Mill.) A. J. Scott.). Among these species, results showed that S. fruticosa had a higher content in protein (4.44 g/100 g FW), ash (5.70 g/100 g FW), salt (2.80 g/100 g FW), chloride (4.84 g/100 g FW), minerals (Na, K, Fe, Mg, Mn, Zn, Cu), total phenolics (0.33 mg GAE/g FW), and antioxidant activity (8.17 µmol TEAC/g FW). Regarding the phenolic classes, S. fruticosa and M. nodiflorum were predominant in the flavonoids, while M. crystallinum, C. maritimum, and S. ramosissima were in the phenolic acids. Moreover, S. fruticosa, S. ramosissima, M. nodiflorum, M. crystallinum, and I. crithmoides showed ACE-inhibitory activity, an important target control for hypertension. Concerning the volatile profile, C. maritimum, I. crithmoides, and D. crassifolium were abundant in terpenes and esters, while M. nodiflorum, S. fruticosa, and M. crystallinum were richer in alcohols and aldehydes, and S. ramosissima was richer in aldehydes. Considering the environmental and sustainable roles of cultivated halophytes using a SCS, these results indicate that these species could be considered an alternative to conventional table salt, due to their added nutritional and phytochemical composition, with potential contribution for the antioxidant and anti-hypertensive effects.

The association of arterial stiffness with estimated excretion levels of urinary sodium and potassium and their ratio in Chinese adults

Arterial stiffness is an independent cardiovascular risk factor. However, the association between sodium/potassium intake and arterial stiffness in the Chinese population is unclear. Therefore, we performed a large, community-based cross-sectional study to reach a more definitive conclusion. The study was conducted at the Third Xiangya Hospital in Changsha between August 2017 and September 2019. Urinary sodium, potassium, and creatinine levels were tested from spot urine samples during physical examinations of each recruited participant. The 24-hour estimated urinary sodium excretion (eUNaE) and estimated urinary potassium excretion (eUKE) levels were calculated using the Kawasaki formula (used as a surrogate for intake). The brachial-ankle pulse wave velocity (baPWV) and ankle brachial index (ABI) were measured using an automatic waveform analyzer. In 22,557 subjects with an average age of 49.3 ± 10.3 years, the relationships of the ABI and baPWV with the levels of eUNaE, eUKE and the ratio of sodium to potassium (Na/K ratio) were analyzed. A significant negative relationship was found between the eUKE and baPWV levels (β = 2.41, p < 0.01), whereas the Na/K ratio was positively associated with baPWV (β = 2.46, p < 0.01), especially in the overweight and hypertensive populations (both pinteraction = 0.04). The association of eUNaE quartiles with baPWV presented a J-shaped curve after adjusting for confounders. In addition, a positive association was observed between the Na/K ratio and the ABI (β = 0.002, p < 0.01). In this study, high potassium and/or low sodium intake was further confirmed to be related to vascular stiffness in Chinese individuals.

Aldosterone: Renal Action and Physiological Effects

Aldosterone exerts profound effects on renal and cardiovascular physiology. In the kidney, aldosterone acts to preserve electrolyte and acid-base balance in response to changes in dietary sodium (Na+ ) or potassium (K+ ) intake. These physiological actions, principally through activation of mineralocorticoid receptors (MRs), have important effects particularly in patients with renal and cardiovascular disease as demonstrated by multiple clinical trials. Multiple factors, be they genetic, humoral, dietary, or otherwise, can play a role in influencing the rate of aldosterone synthesis and secretion from the adrenal cortex. Normally, aldosterone secretion and action respond to dietary Na+ intake. In the kidney, the distal nephron and collecting duct are the main targets of aldosterone and MR action, which stimulates Na+ absorption in part via the epithelial Na+ channel (ENaC), the principal channel responsible for the fine-tuning of Na+ balance. Our understanding of the regulatory factors that allow aldosterone, via multiple signaling pathways, to function properly clearly implicates this hormone as central to many pathophysiological effects that become dysfunctional in disease states. Numerous pathologies that affect blood pressure (BP), electrolyte balance, and overall cardiovascular health are due to abnormal secretion of aldosterone, mutations in MR, ENaC, or effectors and modulators of their action. Study of the mechanisms of these pathologies has allowed researchers and clinicians to create novel dietary and pharmacological targets to improve human health. This article covers the regulation of aldosterone synthesis and secretion, receptors, effector molecules, and signaling pathways that modulate its action in the kidney. We also consider the role of aldosterone in disease and the benefit of mineralocorticoid antagonists. © 2023 American Physiological Society. Compr Physiol 13:4409-4491, 2023.

Flavour Profile of Traditional Dry Sausage Prepared with Partial Substitution of NaCl with KCl

The effects of partial substitution of NaCl with 0%, 20%, 30% and 40% KCl on the physical characteristics, bacterial community and flavour profile of traditional dry sausage were investigated in this study. With the increase in KCl substitution ratio, the moisture content, astringency, bitterness and umami increased significantly, and the saltiness gradually decreased (p < 0.05). The high-throughput sequencing results showed that the dry sausages with KCl substitution had relatively high abundances of Staphylococcus. For volatile compounds, increasing the KCl substitution ratio reduced the formation of aldehydes, ketones and some alcohols, but promoted the formation of acids and esters (p < 0.05). Sensory evaluation and partial least square regression analysis showed that the dry sausages with 20% and 30% KCl were similar in overall physical and microbial properties, flavour profiles and sensory attributes, and the sausages with 40% KCl were characterized by taste defects. Overall, partial substitution of NaCl with 30% KCl could ensure the acceptable flavour and sensory attributes of dry sausages.

Genotypic variation in Na, K and their ratio in 45 commercial cultivars of Indian tropical onion: A pressing need to reduce hypertension among the population

The intake of diets with higher sodium (Na) and lower potassium (K) has been considered a leading factor for the development of hypertension (HTN). Majority of junk, processed and packaged food have higher Na contents. To counter the effects of diet on HTN, the identification of high K/Na ratio plant-based food is needed. Among fruits and vegetables, onion could be the ideal option since it contains high K content. Keeping this in mind, 45 commercially well adapted short day Indian onion cultivars were evaluated for K and Na content and their ratio to isolate suitable cultivars to prevent HTN in the Indian population. The data suggested wide variation among the genotypes for K, Na, and K/Na ratio ranging from 490.2 ± 17.0 to 9160.0 ± 96.7 mg/kg on dry matter basis, 52.7 ± 3.0 to 458.2 ± 61.7 mg/kg on dry matter basis and 3.1 ± 0.7 to 109.5 ± 17.3, respectively. The K content was recorded as significantly highest in the yellow-coloured bulb variety "Arka Pitamber" (9160.1 ± 96.7) followed by Pusa Sona (7933.2 ± 292.8). On the other hand, minimal K was assessed in the white-coloured bulb variety "Agrifound White" (490.3 ± 17.0) followed by Udaipur Local (732.9 ± 93.4). Twelve cultivars exhibited > 7000 mg K content, while nine cultivars recorded < 1500 mg. On the contrary, Na was recorded as significantly highest in the dark-red-coloured bulbs and the lowest in white bulbs. Furthermore, it was determined that there was a more than 35-fold difference observed between the highest (109.5) and lowest (3.1) K/Na ratio in the bulbs of tested cultivars. Cluster analysis revealed three major groups comprising of 23, 13 and 9 genotypes. This information could form the base for public health, food and onion researchers to design suitable cultivars to prevent HTN as a population-wide approach. The next century is going to be food-based for the amelioration of human diseases in a sustainable way without any after-effects on the human body.

Eating more sardines instead of fish oil supplementation: Beyond omega-3 polyunsaturated fatty acids, a matrix of nutrients with cardiovascular benefits

Omega-3 polyunsaturated fatty acids (n-3 PUFA) play a significant role in the prevention and management of cardiometabolic diseases associated with a mild chronic pro-inflammatory background, including type 2 diabetes, hypertension, hypertriglyceridaemia, and fatty liver disease. The effects of n-3 PUFA supplements specifically, remain controversial regarding reducing risks of cardiovascular events. n-3 PUFA supplements come at a cost for the consumer and can result in polypharmacy for patients on pharmacotherapy. Sardines are a well-known, inexpensive source of n-3 PUFA and their consumption could reduce the need for n-3 PUFA supplementation. Moreover, sardines contain other cardioprotective nutrients, although further insights are crucial to translate a recommendation for sardine consumption into clinical practice. The present review discusses the matrix of nutrients contained in sardines which confer health benefits for cardiometabolism, beyond n-3 PUFA. Sardines contain calcium, potassium, magnesium, zinc, iron, taurine, arginine and other nutrients which together modulate mild inflammation and exacerbated oxidative stress observed in cardiovascular disease and in haemodynamic dysfunction. In a common serving of sardines, calcium, potassium, and magnesium are the minerals at higher amounts to elicit clinical benefits, whilst other nutrients are present in lower but valuable amounts. A pragmatic approach towards the consumption of such nutrients in the clinical scenario should be adopted to consider the dose-response relationship effects on physiological interactions. As most recommendations currently available are based on an indirect rationale of the physiological actions of the nutrients found in sardines, randomised clinical trials are warranted to expand the evidence on the benefits of sardine consumption.

Trace Element Quantification in Two Algerian Thymes (Thymus algeriensis Boiss & Reut. and Thymus capitatus (L.) Hoffm. & Link) Using EDXRF Spectrometry

In an attempt to know the elemental composition of two endemic Algerian thyme species, we analyzed eleven mineral and trace elements (Br, Ca, Cr, Cu, Fe, K, Mn, Rb, Sr, V, and Zn) in Thymus algeriensis Boiss & Reut. and Thymus capitatus (L.) Hoffm. & Link. These species are commonly used in Algeria as aromatic and medicinal shrubs. The total concentrations of chemical elements were determined by EDXRF spectrometry. The instrument calibration was assessed through the analysis of certified reference material CRM-336 (Lichen) from the IAEA, Vienna, Austria. The results show that the highest concentrations of the micronutrients (Br, Cr, Cu, Mn, Sr, V, and Zn) were registered in T. algeriensis, while the maximum concentrations of Ca, Fe, and the non-essential element, Rb, were found in T. capitatus. Potassium contents were similar in the two species. The concentrations of essential chemical elements in T. algeriensis leaves were found in the following order: K > Ca > Mn > Fe > Zn > Cu > Cr. However, the order of these elements in T. capitatus was Ca > K > Fe > Zn > Mn > Cu > Cr. Principal component analysis (PCA) showed that T. algeriensis was highly associated with Br, Cr, Cu, Mn, Sr, V, and Zn, while T. capitatus was correlated with Ca, Fe, K, and Rb. Dietary element intakes through ingestion of 1 teaspoon of dry powder (~ 10 g) were estimated and compared to recommended daily intakes and permissible limits under FAO/WHO guidelines. In all cases, these estimates were below those levels. These findings can enhance the dissemination of these medicinal plants, which have medicinal and organoleptic properties, and provide an experiment-based guidance to the pharmaceutical and food industries.

High prevalence of hypertension and target organ damage in patients with 11β-hydroxylase deficiency

BACKGROUND

Prevalence of hypertension and hypertension-mediated organ damage (HMOD) had not been well studied in patients with 11β-hydroxylase deficiency (11β-OHD).

OBJECTIVE

The study was to assess the prevalence and risk factors of hypertension and HMOD in patients with 11β-OHD.

DESIGN

Retrospective cohort analysis in a single medical centre.

PATIENTS

Twenty-eight patients with 11β-OHD were recruited between January 2003 and June 2021, and their diagnosis had been confirmed by Sanger sequencing.

MEASUREMENTS

Blood pressure and clinical indicators for the assessment of HMOD occurrence were collected from the medical records. Medication adherence of antihypertensive drugs and glucocorticoids were determined by the patients' biochemistry. Logistic regression was used to identify factors associated with HMOD.

RESULTS

Prevalence of hypertension and HMOD in the cohort was 100% and 50%, respectively. The kidneys (71.43%) are the organ most commonly damaged by high blood pressure, followed by the heart (64.29%), eyes (57.14%) and brain (21.43%). Risk factors of HMOD were hypokalemia (odds ratio [OR]: 9.16; 95% confidence interval [CI]: 1.634-51.43; p = .012), blood pressure ≥ 180/110 mmHg (OR: 22.0, 95% CI: 3.08-157.34; p = .002) and irregular glucocorticoid use (OR: 3.18, 95% CI: 1.13-8.98; p = .021). Blood pressure ≥ 180/110 mmHg was an independent predictor for HMOD.

CONCLUSION

Hypertension and HMOD are prevalent in patients with 11β-OHD in our study. These findings illustrate the importance of early HMOD evaluation and optimal glucocorticoid medication in 11β-OHD patients.

Associations of sodium and potassium intake with chronic kidney disease in a prospective cohort study: findings from the Hispanic Community Health Study/Study of Latinos, 2008-2017

BACKGROUND

According to dietary recommendations, reduction of sodium intake has potential to reduce Chronic Kidney Disease (CKD) risk; however the role of dietary potassium and the sodium -to- potassium ratio in the development of CKD is unclear.

METHODS

We studied 9778 participants of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) from four US urban communities. Participants were aged 18-74 yrs., free from CKD at baseline in 2008-2011 and re-examined between 2014 and - 2017. Dietary intake of sodium, potassium and the ratio of dietary sodium -to- potassium were measured from two baseline 24-h dietary recalls. Incident CKD was defined as: 1) estimated glomerular filtration rate (eGFR) decline of 1 unit per year and eGFR < 60 ml/min/1.73m2 or 2) albumin to creatinine ratio ≥ 30 mg/g at the follow-up visit. We used multivariable survey weighted Poisson regression to estimate adjusted incident rates of incident CKD.

RESULTS

At baseline, mean age was 41 years. Average follow up time was 6.2 years. From fully adjusted Poisson regression analyses, self-reported sodium intake was not associated with incident CKD. However, for each 500 mg decrement in potassium intake, there was an 11% increase risk of incident CKD (IRR = 1.11, 95% CI = 1.00, 1.24). Additionally, every 1 M ratio increment of sodium -to -potassium ratio was associated with a 21% increased risk of incident CKD (IRR = 1.21, 95% CI = 1.02, 1.45), p < 0.05).

CONCLUSIONS

We conclude that diets low in potassium and high in sodium are associated with increased risk of developing chronic kidney disease among healthy US Hispanic/Latino adults.

Nutrients and Dietary Approaches in Patients with Type 2 Diabetes Mellitus and Cardiovascular Disease: A Narrative Review

Cardiovascular disease (CVD) is the most common cause of morbidity and mortality in developed countries. The prevalence of CVD is much higher in patients with type 2 diabetes mellitus (T2DM), who may benefit from lifestyle changes, which include adapted diets. In this review, we provide the role of different groups of nutrients in patients with T2DM and CVD, as well as dietary approaches that have been associated with better and worse outcomes in those patients. Many different diets and supplements have proved to be beneficial in T2DM and CVD, but further studies, guidelines, and dietary recommendations are particularly required for patients with both diseases.

100% Fruit juice intake and cardiovascular risk: a systematic review and meta-analysis of prospective and randomised controlled studies

PURPOSE

The relationship between 100% fruit juice (100%FJ) consumption and cardiovascular risk is object of debate: indeed, recently published investigations provided new but discrepant evidence on this important question and International dietary guidelines are not in agreement on recommendations about fruit juice consumption. Therefore, we performed a meta-analysis of the prospective studies and the randomised controlled trials (RCTs) that explored the relationship between 100%FJ intake, cardiovascular risk profile and risk of cardiovascular events.

METHODS

We performed a systematic search of publications up to August 2019. Summary relative risks and exploration of linearity of the association were estimated for prospective studies and summary mean differences (MDs) calculated for RCTs.

RESULTS

A total of 21 prospective studies and 35 RCTs met the inclusion criteria. Dose-response analysis detected a significant inverse association between low-moderate 100%FJ consumption and risk of stroke (up to 200 ml/day) or total CV events (up to 170 ml/day) compared with no consumption, with a non-linear relationship (p for non-linearity < 0.05). No significant association was found for coronary heart disease and diabetes risk. In RCTs, a favorable and significant effect of 100%FJ intake was detected on blood pressure (systolic, MD: - 3.14 mmHg; diastolic, MD: - 1.68 mmHg), arterial compliance (carotid-femoral pulse wave velocity, - 0.38 m/s) and endothelial function (flow-mediated dilation, 2.10%). Neutral effects were found on body weight, blood lipids and glucose metabolism.

CONCLUSIONS

The results of these analyses indicate that 100%FJ consumption is not associated with higher CV risk. A non-linear inverse dose-response relationship occurs between 100%FJ consumption and CV disease, in particular for risk of stroke, probably mediated by the decrease in blood pressure.

TRIAL REGISTRATION

PROSPERO registration number (CRD42019135577).

Potassium

Potassium is an essential nutrient that performs a vital role in cellular functions including maintaining fluid balance and osmolality of cells. Potassium balance is maintained by the kidney and the majority of ingested potassium is excreted in the urine. There is strong evidence of a negative association between dietary potassium and blood pressure, and some evidence (much of it indirect) of negative associations between dietary potassium and cardiovascular disease (particularly stroke and coronary heart disease) and kidney disease (chronic renal failure, and kidney stones). Blood pressure lowering is particularly associated with high potassium and low sodium diets. Important dietary sources of potassium include fruit and vegetables (including rice, potatoes, legumes and wholegrains), dairy products, and animal proteins. Worldwide, diets are low in potassium compared to dietary guidelines. Interventions focused on increasing dietary potassium will have major benefits including improvements in diet, reducing non-communicable disease and enhancing planetary health.

Thiazide-Sensitive NCC (Sodium-Chloride Cotransporter) in Human Metabolic Syndrome: Sodium Sensitivity and Potassium-Induced Natriuresis

The thiazide-sensitive sodium-chloride cotransporter (NCC;SLC12A3) is central to sodium and blood pressure regulation. Metabolic syndrome induces NCC upregulation generating sodium-sensitive hypertension in experimental animal models. We tested the role of NCC in sodium sensitivity in hypertensive humans with metabolic syndrome. Conversely, oral potassium induces NCC downregulation producing potassium-induced natriuresis. We determined the time course and magnitude of potassium-induced natriuresis compared with the natriuresis following hydrochlorothiazide (HCTZ) as a reference standard. We studied 19 obese hypertensive humans with metabolic syndrome during 13-day inpatient confinement. We determined sodium sensitivity by change in 24-hour mean systolic pressure by automated monitor from days 5 (low sodium) to 10 (high sodium). We determined NCC activity by standard 50 mg HCTZ sensitivity test (day 11). We determined potassium-induced natriuresis following 35 mmol KCl (day 13). We determined (1) whether NCC activity was greater in sodium-sensitive versus sodium-resistant participants and correlated with sodium sensitivity and (2) time course and magnitude of potassium-induced natriuresis following 35 mmol KCl directly compared with 50 mg HCTZ. NCC activity was not greater in sodium-sensitive versus sodium-resistant humans and did not correlate with sodium sensitivity. Thirty-five-millimoles KCl produced a rapid natriuresis approximately half that of 50 mg HCTZ with a greater kaliuresis. Our investigation tested a key hypothesis regarding NCC activity in human hypertension and characterized potassium-induced natriuresis following 35 mmol KCl compared with 50 mg HCTZ. In obese hypertensive adults with metabolic syndrome ingesting a high-sodium diet, 35 mmol KCl had a net natriuretic effect approximately half that of 50 mg HCTZ.

Measurement of selected trace elements in Olea europaea L. cv. 'Sigoise'

BACKGROUND

Olive-trees (Olea europaea L.) are the dominant rustic trees cultivated in the Mediterranean agricultural zones. Major and micronutrients play an indispensable role in their plant physiological functions although; the effect of trace elements on metabolic processes has not been sufficiently investigated, especially in olive-trees.

METHODS

In the current study, we have used X-ray fluorescence (XRF) spectrometry to determine selected major and trace elements (Br, Cu, Fe, K, Mn, P, Rb and Zn) in the main olive cultivar cultivated in Algeria, cv.'Sigoise'. Certified reference materials viz. IAEA-336 (Lichen) and NIST-1646a (Estuarine sediment) were evaluated simultaneously with the soil and plant samples for quality control of the analytical method.

RESULTS

The results show that Fe and Mn concentrations were superior in leaves than fruits. However large amounts of K, Cu and Rb were accumulated in the olive-fruits. The contents of all chemical elements were above the threshold limits for possible plant nutrient deficiencies, except for P whose concentration was in borderline requirement of olive trees. High values of a translocation factor index were found for K, Cu and Rb (TFs > 4). Principal component analysis (PCA) indicated that K was highly related with olives-fruits, suggesting that the fruit was the principal organ of K storage. Furthermore, dietary element intake through consuming olives was also estimated and compared to recommended daily intakes (RDIs) and daily permissible limits (DPLs). The estimations of chemical element intakes were below the DPLs set by WHO/FAO guidelines for human nutrition.

CONCLUSION

The present work indicates that the concentrations of macro- and microelements (Cu, Fe, K, Mn and Zn) were above the threshold limits for possible plant deficiencies except for P, and this cultivar can easily accumulate high amount of K in their organs (predominance in olives). These findings will be used to achieve efficient fertilization for O. europaea orchards.

Results of the CARDIA study suggest that higher dietary potassium may be kidney protective

The association between dietary sodium and potassium intake with the development of kidney disease remains unclear, particularly among younger individuals. Here, we determined whether dietary sodium and potassium intake are associated with incident chronic kidney disease (CKD) using data from 1,030 adults (age 23-35 in 1990-1991) from the Coronary Artery Risk Development In Young Adults study, based on repeated measurements of estimated glomerular filtration rate (eGFR) and urinary albumin to creatinine ratio (ACR) from 1995 through 2015. Urinary sodium and potassium excretion (mg/day), calculated from three 24-hour urine collections in 1990-1991, were averaged to measure sodium and potassium intake. Serum creatinine was used to calculate eGFR using the CKD EPI equation; spot urine albumin and creatinine were used to calculate ACR, each at five visits from 1995-1996 through 2015-2016. CKD was defined as decreased eGFR (under 60 ml/min/1.73m2) or the development of albuminuria (ACR over 30 mg/g). We used log binomial regression models adjusted for socio-demographic, behavioral, and clinical factors to determine whether sodium and potassium intake were associated with incident CKD (decreased eGFR or developed albuminuria) among those free of CKD in 1995. Dietary sodium intake was not significantly associated with incident CKD. However, every 1,000 mg/day increment of potassium intake in 1990 was significantly associated with a 29% lower risk of incident albuminuria (relative risk 0.71, 95% confidence interval 0.53, 0.95), but not eGFR. Thus, higher dietary potassium intake may protect against the development of kidney damage, particularly albuminuria.

Urinary sodium-to-potassium ratio and body mass index in relation to high blood pressure in a national health survey in Chile

Several lifestyle and sociodemographic factors are associated with blood pressure (BP). The authors conducted a retrospective study of 4870 subjects from the National Health Survey 2009 in Chile to identify exposure factors associated with increasing BP levels. Subjects with isolated urinary excretion of sodium (n = 2873), potassium, and creatinine were included to estimate daily salt intake and urinary sodium/potassium (Na/K) ratio. Hypertension was defined according to European guidelines 2018 and American guidelines ACC/AHA 2017. Proportional odds models were developed to analyze education level, sedentarism, smoking, alcohol intake, estimated urinary Na/K ratio, estimated daily salt intake, and body mass index (BMI) as factors associated with increasing BP levels (from high-normal BP to hypertension). Logistic regression models were checked for overdispersion. Mean age and BMI of the population were 42 years old and 27 kg/m² , respectively; 19% had low education level and 27% had hypertension according to European guidelines, whereas 47% according to ACC/AHA criteria. Mean estimated urinary Na/K ratio was 4 ± 2, and mean salt consumption was 10 ± 2 g/day. Estimated urinary Na/K ratio (OR, 1.11; 95% CI, 1.01-1.21), BMI (OR, 1.10; 95% CI, 1.07-1.13), estimated daily salt intake (OR, 1.10; 95% CI, 1.03-1.17), and alcohol intake (OR, 1.03; 95% CI, 1.01-1.05) were significantly associated with hypertension. This study highlights that a healthy diet and weight control should be important components of BP management plans, and it suggests that public policies should include close monitoring of these factors to reduce hypertension prevalence and improve its management in a Latino population.

Should we eat more potassium to better control blood pressure in hypertension?

Changes in lifestyle and nutrition are recommended as the first-step approach to the management of hypertension by all national and international guidelines. Today, when considering nutritional factors in hypertension, almost all the attention is focused on the reduction of salt intake to improve blood pressure (BP) control. Changes in potassium intake are only briefly evoked in guidelines. Few physicians actually think about proposing to eat more foods that are high in potassium (fruits, vegetables, nuts) to better control BP. Yet, during the last 40 years, increasing evidence has accumulated demonstrating that increasing potassium intake, either with food products or with supplements, is associated with significant reductions of both systolic and diastolic BP. The hypotensive effect of potassium is particularly marked in patients with hypertension and in subjects with a very high sodium intake, suggesting that potassium counterbalances the effects of sodium. In addition, several meta-analyses have now confirmed that high potassium intake reduces the risk of stroke by ∼ 25%. Finally, increasing potassium in the diet may perhaps be beneficial for some renal patients, as post hoc analyses have suggested that a high potassium intake may retard the decline of renal function in patients with early chronic kidney disease (CKD) stages. However, high potassium intake may be risky and sometimes even dangerous in hypertensive patients with CKD stages 3-5, specifically diabetics. In this context, however, as the level of evidence remains low, more prospective clinical studies are needed. The goal of this review is to discuss the actual evidence that supports the recommendation to eat more potassium in order to better control BP in essential hypertension and to review the restrictions in CKD patients with hypertension.

Seeds

A wide variety of plant species provide edible seeds. Seeds are the dominant source of human calories and protein. The most important and popular seed food sources are cereals, followed by legumes and nuts. Their nutritional content of fiber, protein, and monounsaturated/polyunsaturated fats make them extremely nutritious. They are important additions to our daily food consumption. When consumed as part of a healthy diet, seeds can help reduce blood sugar, cholesterol, and blood pressure.

Deletion of the serine protease CAP2/Tmprss4 leads to dysregulated renal water handling upon dietary potassium depletion

The kidney needs to adapt daily to variable dietary K⁺ contents via various mechanisms including diuretic, acid-base and hormonal changes that are still not fully understood. In this study, we demonstrate that following a K⁺-deficient diet in wildtype mice, the serine protease CAP2/Tmprss4 is upregulated in connecting tubule and cortical collecting duct and also localizes to the medulla and transitional epithelium of the papilla and minor calyx. Male CAP2/Tmprss4 knockout mice display altered water handling and urine osmolality, enhanced vasopressin response leading to upregulated adenylate cyclase 6 expression and cAMP overproduction, and subsequently greater aquaporin 2 (AQP2) and Na⁺-K⁺-2Cl⁻ cotransporter 2 (NKCC2) expression following K⁺-deficient diet. Urinary acidification coincides with significantly increased H⁺,K⁺-ATPase type 2 (HKA2) mRNA and protein expression, and decreased calcium and phosphate excretion. This is accompanied by increased glucocorticoid receptor (GR) protein levels and reduced 11β-hydroxysteroid dehydrogenase 2 activity in knockout mice. Strikingly, genetic nephron-specific deletion of GR leads to the mirrored phenotype of CAP2/Tmprss4 knockouts, including increased water intake and urine output, urinary alkalinisation, downregulation of HKA2, AQP2 and NKCC2. Collectively, our data unveil a novel role of the serine protease CAP2/Tmprss4 and GR on renal water handling upon dietary K⁺ depletion.

Daily Intake of Sodium and Potassium Among Diverse US Hispanics/Latinos, the Hispanic Community Health Study/Study of Latinos

BACKGROUND

High sodium and low potassium consumption are risk factors for hypertension. The objectives of this study were to describe usual daily intake of sodium and potassium among US Hispanics/Latinos of diverse background groups and estimate the proportion meeting guidelines for dietary sodium and potassium intake.

METHODS

We studied 16,171 participants of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a diverse group of self-identified Hispanics/Latinos aged 18-74 years from 4 US communities. In 2008-2011, all HCHS/SOL participants underwent a standardized examination. Median usual daily intake of dietary sodium and potassium were derived from two 24-hour diet recalls; standard errors and 95% confidence intervals (CIs) were calculated using boot strap methods. Meeting 2015 US Department of Agriculture guidelines was defined as an intake of <2,300 mg/day of sodium and ≥4,700 mg/day of potassium.

RESULTS

Among US Hispanics/Latinos, median usual daily intake of sodium was 2,574 mg (95% CI: 2,547, 2,600) among women and 3,747 mg (95% CI: 3,697, 3,796) among men. Median usual daily intake of potassium was 2,069 mg (95% CI: 2,046, 2,092) among women and 2,649 mg (95% CI: 2,615, 2,683) among men. Overall, only 21.3% (95% CI: 20.2%, 22.4%) of the US Hispanic/Latino population met 2015 recommendations for sodium and 0.6% (95% CI: 0.4%, 0.8%) for potassium.

CONCLUSIONS

Among US Hispanics/Latinos intake of sodium is too high and potassium too low. Strategies to reduce sodium intake while simultaneously increasing intake of potassium in this US population are warranted.

High sodium intake and sodium to potassium ratio may be linked to subsequent increase in vascular damage in adults aged 40 years and older: the Korean multi-rural communities cohort (MRCohort)

PURPOSE

Subclinical vascular damage is a chronic intermediate process in cardiovascular disease (CVD) and high sodium (Na) has been regarded as an adverse factor in subclinical vascular health; however, the longitudinal relationship between Na intake and subclinical vascular damage has not been studied. We aimed to evaluate the longitudinal relationship of dietary Na intake and sodium to potassium ratio (Na:K) with brachial-ankle pulse wave velocity (baPWV) and carotid intima media thickness (cIMT) in healthy adults aged 40 years and older in Korea.

METHODS

The present study was based on participants (n = 2145 for baPWV analysis and n = 2494 for cIMT analysis) who visited three times during 2005-2013 (median 5.3 years of follow-up). We used both dietary Na intake and Na:K at baseline and its average (baseline, 2nd, 3rd), which was obtained from food frequency questionnaire (FFQ) as exposure at every visit. baPWV and cIMT levels at the third visit and change from baseline to the third visit were used to represent the level of subclinical vascular damage.

RESULTS

After adjustment for potential confounders, significant positive relationships between dietary Na intake and both baPWV_3rd and cIMT_3rd were observed (baPWV: p for trend ≤ 0.0001 for Na_average; cIMT: p for trend = 0.013 for Na_average). Compared with Na:Ks less than 1.0, the levels of both baPWV and cIMT were higher for participants with Na:Ks over 1.0 (baPWV: p for trend = 0.0002 for Na:K_average; cIMT: p for trend = 0.005 for Na:K_average). Similar significant trends were shown in relationships between dietary Na intake and Na:K and changes in baPWV and cIMT levels.

CONCLUSIONS

In conclusion, dietary Na intake and Na:K may be positively linked to subsequent baPWV and cIMT levels in adults aged 40 years and older in Korea. Our findings may provide informative evidence on subclinical vascular damage, particularly for populations with relatively high dietary Na intake and low dietary K intake.

The Hypertension Pandemic: An Evolutionary Perspective

Hypertension affects over 1.2 billion individuals worldwide and has become the most critical and expensive public health problem. Hypertension is a multifactorial disease involving environmental and genetic factors together with risk-conferring behaviors. The cause of the disease is identified in ∼10% of the cases (secondary hypertension), but in 90% of the cases no etiology is found (primary or essential hypertension). For this reason, a better understanding of the mechanisms controlling blood pressure in normal and hypertensive patients is the aim of very active experimental and clinical research. In this article, we review the importance of the renin-angiotensin-aldosterone system (RAAS) for the control of blood pressure, focusing on the evolution of the system and its critical importance for adaptation of vertebrates to a terrestrial and dry environment. The evolution of blood pressure control during the evolution of primates, hominins, and humans is discussed, together with the role of common genetic factors and the possible causes of the current hypertension pandemic in the light of evolutionary medicine.

Dietary sodium, dietary potassium, and systolic blood pressure in US adolescents

Both high sodium and low potassium diets are associated with hypertension, but whether these risk factors are distinct or overlapping has not been thoroughly investigated. The authors evaluated the relationship between dietary sodium, potassium, and high systolic blood pressure among 4716 adolescents aged 12 to 14 years who participated in the National Health and Nutrition Examination Survey from 1999 to 2012. There was no association with blood pressure across most values of sodium or potassium intake. However, participants who reported sodium intake ≥7500 mg/d, potassium <700 mg/d, or sodium-potassium ratio ≥2.5 had increased odds for high systolic blood pressure (≥95th percentile for age, sex, and height). Although the high sodium and low potassium groups did not overlap, 49.2% of these adolescents also had a sodium-potassium ratio ≥2.5. In young adolescents, both excessive sodium and limited potassium are associated with high systolic blood pressure, but the balance between sodium and potassium intake may be more useful in explaining blood pressure in this population.

A membrane-anchored fluorescent probe for detecting K(+) in the cell microenvironment

Cell-surface fluorescent probes are effective tools in cell biology and engineering. Here, we for the first time report a diacyllipid-aptamer conjugate-based fluorescent probe which could anchor on cell membrane for real-time tracking of potassium ions in the cell microenvironment.

Effect of partial substitution of NaCl by KCl on physicochemical properties, biogenic amines and N-nitrosamines during ripening and storage of dry-cured bacon

Effects of three salting treatments (Formulation II: 80 % NaCl + 20 % KCl; Formulation III: 60 % NaCl + 40 % KCl and Formulation IV: 40 % NaCl + 60 % KCl) on physicochemical properties, residual nitrite, N-nitrosamines and biogenic amines were compared with those of control bacons (Formulation I: 100 % NaCl) during processing and storage. Results showed that there were no significant differences among treatments for moisture, pH, and total volatile basic nitrogen (TVBN) content in dry-cured bacons during processing. The replacement of 40 % or less NaCl by KCl had no negative effects on the sensory quality of bacons during processing. Formulation III significantly reduced putrescine, cadaverine and histamine contents and enhanced nitrite residues compared with the control. After 12-day ripening and during storage, the substitution of NaCl by 60 % KCl significantly increased the N-nitrosodimethylamine (NDMA) content than the control. Principal component analysis showed that there were positive correlations between TVBN, biogenic amines (putrescine, cadaverine, histamine and tyramine) and NDMA, and negative correlation between NDMA and nitrite. These findings suggested the partial substitution of NaCl by KCl could be utilized for producing reduced-sodium dry-cured bacons to improve safety of finished products.

Dietary potassium and the renal control of salt balance and blood pressure

Dietary potassium (K(+)) intake has antihypertensive effects, prevents strokes, and improves cardiovascular outcomes. The underlying mechanism for these beneficial effects of high K(+) diets may include vasodilation, enhanced urine flow, reduced renal renin release, and negative sodium (Na(+)) balance. Indeed, several studies demonstrate that dietary K(+) intake induces renal Na(+) loss despite elevated plasma aldosterone. This review briefly highlights the epidemiological and experimental evidences for the effects of dietary K(+) on arterial blood pressure. It discusses the pivotal role of the renal distal tubule for the regulation of urinary K(+) and Na(+) excretion and blood pressure and highlights that it depends on the coordinated interaction of different nephron portions, epithelial cell types, and various ion channels, transporters, and ATPases. Moreover, we discuss the relevance of aldosterone and aldosterone-independent factors in mediating the effects of an altered K(+) intake on renal K(+) and Na(+) handling. Particular focus is given to findings suggesting that an aldosterone-independent downregulation of the thiazide-sensitive NaCl cotransporter significantly contributes to the natriuretic and antihypertensive effect of a K(+)-rich diet. Last but not least, we refer to the complex signaling pathways enabling the kidney to adapt its function to the homeostatic needs in response to an altered K(+) intake. Future work will have to further address the underlying cellular and molecular mechanism and to elucidate, among others, how an altered dietary K(+) intake is sensed and how this signal is transmitted to the different epithelial cells lining the distal tubule.

Gender differences in the relationship between risk of hypertension and fruit intake

OBJECTIVE

To investigate the relationship between hypertension and fruit intake in an Asian population.

METHOD

This study was based on the data from 2007, 2008 and 2009 Korea National Health and Nutrition Examination Survey. In the final analysis, a total of 9791 subjects (men=3819, women=5972) were included. Daily energy and nutrient intakes were assessed using 24-h recall. The odds ratios (ORs) for hypertension were assessed by using logistic regression and multivariable models.

RESULTS

A total of 10.6% of individuals were classified as having hypertension. Compared with the lowest quintile of fruit intake, the fifth quintile showed the lowest likelihood of hypertension (OR 0.73; 95% confidence interval [CI], 0.61-0.88) after adjusting for age and gender. For women, the likelihood of hypertension in the 2nd, 3rd, 4th and 5th quintiles of fruit intake decreased to 0.67 (95% CI, 0.34-1.30), 0.76 (0.56-1.05), 0.90 (0.67-1.22) and 0.54 (0.38-0.77), respectively, after adjusting for confounding factors (P value for trend=0.0011). An inverse association of fruit intake and hypertension was shown only in non-obese women. For men and obese women, there was no relationship between fruit intake and hypertension.

CONCLUSION

Dietary fruit recommendation for hypertension should be taken into account together with ethnic background, gender as well as the presence of obesity in individuals.