Search Results (175)

(1) Background: The urate-lowering effects of three iridoid glycosides, which are paederosidic acid, paederosidic acid methyl ester, and paederoside, isolated from Paederia foetida and the protection they provide against hyperuricemia-induced kidney injury were investigated in a rat model. (2) Methods: A hyperuricemia (HUA) rat model was established in Sprague-Dawley (SD) rats through intraperitoneal potassium oxonate (PO) and intragastrical adenine for 2 weeks. Subsequently, rats in the pharmaceutical intervention groups received corresponding drug treatments at a concentration of 40 mg/kg/day, maintained consistently for 7 days. (3) Results: The results showed that three compounds reduced serum urate (SU), creatinine (CRE), and blood urea nitrogen (BUN) levels and that the urinary excretion levels of uric acid, urine urea nitrogen, and creatinine increased. Furthermore, the administration of three iridoid glycosides enhanced renal filtration capacity, as demonstrated by the elevated 24 h creatinine clearance rate (CCR) and 24 h uric acid clearance rate (CUA); improved the fraction excretion of uric acid (FEUA); and attenuated renal damage. Finally, three iridoid glycosides promoted uric acid excretion in HUA rats by downregulating URAT1 and GLUT9 and upregulating ABCG2, OAT1, and OAT3. Moreover, the molecular docking results further corroborated the finding that the three compounds can bind to multiple sites of the uric acid transporter via hydrogen, P-π, and hydrophobic bonds. (4) Conclusions: The three iridoid glycosides were found to lower SU levels by increasing uric acid excretion. They are promising natural products for the prevention of HUA and HUA-induced kidney injury. Full article

Background/Objectives: Recent Japanese guidelines recommend using the average sodium-to-potassium (Na/K) ratio from casual urine samples to assess hypertension and cardiovascular risk, suggesting cutoffs of 2 (optimal) and 4 (feasible). We aimed to evaluate the proportion of Korean individuals who would be classified as having elevated Na/K ratios using these cutoffs, based on random urine Na/K measurements obtained from the nationally representative Korea National Health and Nutrition Examination Survey (KNHANES) dataset. Methods: We analyzed 50,440 participants from the KNHANES 2016–2023 with available random urine Na and K results. Annual urinary Na/K ratios were calculated, and the prevalence of ratios ≥2 and ≥4 was assessed by age and sex using sampling weights. Results: The weighted median Na/K ratios were consistently lower than the weighted means, indicating skewed distributions. From 2016 to 2023, the weighted median and mean values increased from 2.3 and 2.7 to 2.8 and 3.3, respectively. The prevalence of a Na/K ratio ≥2 increased from 60.5% to 72.0%, and that of a ratio ≥4 increased from 16.9% to 28.3%. A U-shaped trend in Na/K ≥4 prevalence was observed by age, highest among those <20 and ≥70 years. Males had a higher prevalence than females in all age groups except 20–29. Conclusions: A growing proportion of Koreans exceeded Na/K cutoffs of 2 and 4 over time. Age- and sex-specific variation suggests tailored interpretation may be necessary when applying these thresholds in population health monitoring. Full article

The appearance rate of nutrients into systemic circulation affects hormones like insulin and through that efficiency of growth. This also affects mineral requirements critical for metabolism, notably phosphate (P), magnesium (Mg), and potassium (K). Fasting animals have a downregulated metabolism, upon which P, Mg, and K are exported from their cells into the blood and are subsequently excreted in their urine. Abrupt resumption of feed intake, especially of highly glycemic feeds, creates an acute need for these minerals, which can result in deficiency symptoms, particularly with P deficiency. In human medicine, this is called refeeding syndrome: a large meal after a period of fasting can prove fatal. Young animals seem to be especially sensitive, likely driven by their ability to grow rapidly and thus to drastically upregulate their metabolism in response to insulin. Symptoms of P deficiency are fairly a-specific and, consequently, not often recognized. They include edema, which makes it appear as if piglets are growing well, explaining the high gain/feed rate typically seen immediately after weaning, even when piglets are eating at or below the maintenance requirements. Phosphate deficiency can also result in hypoxia and hypercarbia, which may trigger ear necrosis, Streptococcus suis infections, or even death. Hypophosphatemia can also trigger rhabdomyolysis, which may contribute to tail-biting, but this requires further study. Arguably, when fasting cannot be avoided, diets for newly weaned piglets should be formulated to avoid these problems by lowering their glycemic load and by formulating diets according to the piglets’ actual requirements inspired by their genuine intake and health and not simply by extrapolating from older animals. Full article

Renal function refers to the combined actions of the glomerulus and tubular system to achieve homeostasis in bodily fluids. While the glomerulus is essential in the first step of urine formation through a coordinated filtration mechanism, the tubular system carries out active mechanisms of secretion and reabsorption of solutes and proteins using specific transporters in the epithelial cells. The assessment of renal function usually focuses on glomerular function, so the tubular function is often underestimated as a fundamental part of daily clinical practice. Therefore, it is essential to properly understand the tubular physiological mechanisms and their clinical association with prevalent human pathologies. This review discusses the primary solutes handled by the kidneys, including glucose, amino acids, sodium, potassium, calcium, phosphate, citrate, magnesium and uric acid. Additionally, it emphasizes the significance of physicochemical characteristics of urine, such as pH and osmolarity. The use of a concise methodology for the comprehensive assessment of urine should be strengthened in the basic training of nephrologists when dealing with problems such as water and electrolyte balance disorders, acid-base disorders, and harmful effects of commonly used drugs such as chemotherapy, antibiotics, or diuretics to avoid isolated replacement of the solute without carrying out comprehensive approaches, which can lead to potentially severe complications. Full article

Background: Primary aldosteronism is characterized by elevated aldosterone levels, leading to adverse effects such as hypertension, hypokalaemia and increased risk for cardiovascular and cerebrovascular events. Aldosterone impacts the central nervous system by promoting vascular remodelling and oxidative stress, potentially impairing cognitive function. The presence of mineralocorticoid receptors in the hippocampus, a key region for cognition, further suggest a link between primary aldosteronism and cognitive dysfunction. This study aims to further explore the association between hyperaldosteronism and cognitive impairment. Methods: In this pilot study we examined 15 individuals with primary aldosteronism and arterial hypertension alongside 15 age- and sex-matched controls with essential hypertension, all free of previous cerebrovascular events. Clinical and archival laboratory data were obtained. Cognitive function was assessed using the Mini-Mental State Examination and Montreal Cognitive Assessment. Results: Participants with primary aldosteronism had higher blood pressure values, longer duration of hypertension, lower serum potassium levels and higher 24 h urine albumin excretion rate compared to controls. Comorbidities, other characteristics and laboratory values were comparable across the two groups. No differences were observed in Mini-Mental State Examination scores, but Montreal Cognitive Assessment scores were significantly lower in the primary aldosteronism group (25.1 ± 2.2 vs. 27.1 ± 2.2, p = 0.021). Trends of poorer performance in language and attention/executive function domains were noted in primary aldosteronism individuals, as well as a higher number of pathological Montreal Cognitive Assessment scores (7 vs. 3). No significant correlations were found between cognitive test results and aldosterone concentrations or blood pressure in primary aldosteronism group. However, importantly, multiple regression analysis showed that aldosterone levels have a significant impact on Montreal Cognitive Assessment test, independent of blood pressure or duration of hypertension. Conclusions: This study supports an association between hyperaldosteronism and cognitive dysfunction, underscoring the need for more active detection and targeted treatment of primary aldosteronism. These findings warrant further research in larger cohorts to better elucidate this relationship. Full article

Background/Objectives: The urine sodium/potassium (Na/K) ratio can potentially be used to detect dietary habits that contribute to hypertension. In this prospective cohort interventional trial, we aimed to verify whether private insurance sales staff can help clients change their lifestyle habits based on their urinalysis results. Methods: Clients of the life insurance company (20–65 years old) who were considered to have “high risk” lifestyle factors, which was defined as having high values for two or more of the following indicators: body mass index, blood pressure, triglycerides, liver enzymes, and glucose metabolism, were included. The clients were randomly assigned to three groups: a face-to-face (FF) intervention by sales staff (n = 83), non-FF (Non-FF) intervention via a social networking service (n = 87), and no intervention (Control) (n = 58). Urinalysis and surveys about diet and exercise habits were conducted before and after a 3-month interventional period in all groups. Three interventions were performed for the FF and Non-FF groups, including dietary advice based on urinalysis results, education encouraging reduced salt intake and increased locomotor activity, and viewing an educational video. The Control group only received their urinalysis results by mail. Results: The participants’ mean age was 44.0 years old. Significant improvements in estimated potassium intake were observed in the Non-FF group, and significant reductions in urine Na/K ratios were noted in both the FF and Non-FF groups. Multiple logistic regression analysis indicated that watching the video was the most effective factor for decreasing the urine Na/K ratio (odds ratio = 1.869). The total points for dietary behavior, based on the questionnaire, significantly improved among the individuals who watched the video. Conclusions: This study demonstrates the potential for private health insurance companies to contribute to health promotion and introduces a novel strategy for improving lifestyle habits among individuals at high risk of lifestyle-related diseases. Full article

Aldosterone, a mineralocorticoid hormone synthesised in the adrenal cortex, is essential for maintaining electrolyte balance and fluid homeostasis. Its role in feline physiology remains underexplored, despite its importance in regulating sodium reabsorption and potassium excretion via mineralocorticoid receptors in renal tubules. This study is warranted given aldosterone’s importance in cats, particularly in light of their unique physiological traits, including highly concentrated urine and sensitivity to hydration status. Primary hyperaldosteronism, the most common feline adrenocortical disorder, contributes to arterial hypertension and chronic kidney disease, yet often remains underdiagnosed due to overlapping symptoms like hypokalaemia and hypertension. This research aimed to validate a liquid chromatography–tandem mass spectrometry (LC-MS/MS) method to measure serum aldosterone and to establish a reference interval in a population of healthy cats across a broad age range. The method demonstrated high precision and accuracy, with inter-assay coefficients of variation under 15%. Analysis of 49 healthy cats (40 young, 9 old) revealed a reference interval of 5.0–78.4 pg/mL (13.8–217.2 pmol/L). These findings provide a robust framework for diagnosing aldosterone-related disorders in cats and underscore the need for species-specific diagnostic tools. Improved understanding of aldosterone’s role could refine treatment strategies and enhance outcomes for affected feline patients. Full article

Background/Objectives: To compare the results of oral chemolysis of non-opaque and semi-opaque kidney stones using potassium citrate (PS) and allopurinol + potassium citrate (ALPS) prospectively without advanced metabolic analysis. Methods: Between 2020 and 2022, 59 patients aged 19–60 years with non-obstructive, semi-opaque, and non-opaque kidney stones of 8–13 mm in size detected by non-contrast tomography were investigated, and oral chemolysis (potassium citrate 10 mEq 2 × 2, allopurinol 10 mEq 2 × 2) was initiated. Patients were divided into two groups, potassium citrate (PS) and allopurinol + potassium citrate (ALPS), according to the treatment to be received. The essential characteristics of the groups, monthly laboratory values throughout the process, and the stone size measured by non-contrast tomography at the initial presentation and the stone size after a mean of 9–10 months of treatment was recorded and compared. Results: The inferior calyx was the most common location. There were no statistically significant differences between the groups with regard to age, sex, size, location or side. Before treatment, the mean stone size was 11.01 ± 2.27 mm in the potassium citrate group and 11.1 ± 2.03 mm in the other group. Following treatment, both groups changed significantly, but did not differ statistically (p < 0.001) (p = 0.281). The mean urine pH of all patients changed considerably after treatment (p < 0.001). Conclusions: Potassium citrate-based urinary alkalisation can be started for non-opaque and semi-opaque kidney stones without metabolic analysis if the urine pH is appropriate. The combination of allopurinol with potassium citrate has no therapeutic advantage. Full article

Background/Objectives: Urolithiasis is a common disease in Western societies, affecting approximately 10% of the population, and more often men than women. The formation of renal calculi is a complex process, including various compounds and proteins. The aim of this study is to compare differences between the trace element concentrations in male and female renal calculi as well as differences between the trace element concentrations in different stone types. Material and Methods: Renal calculi specimens were obtained during elective nephrolithotripsy procedures. Crystallography of renal calculi was performed using X-ray diffraction; an elemental analysis was performed using Inductively Coupled Plasma–Optical Emission Spectrometry. Statistical analysis was performed to assess the differences in the metal element concentration between men and women. The second part of the analysis measured the differences in the metal element concentration between stones containing calcium phosphate (CaP) and pure calcium oxalate (CaOx) stones. Results: The renal calculi (n = 20) obtained from the male patients had a lower potassium concentration than the calculi (n = 24) from the female patients: 393.4 vs. 792.3 mg/kg, p = 0.007. A comparison of the CaP calculi and CaOx calculi showed a higher zinc concentration (p < 0.001) and potassium concentration (p < 0.001) in the stones containing calcium phosphate. Conclusions: The renal calculi from females had a significantly higher potassium content than those from males. This difference was not correlated with hyperkalemia or the blood potassium levels, suggesting a sex-dependent role of uromodulin in stone formation. The stones containing calcium phosphate exhibited higher zinc and potassium concentrations compared to the pure calcium oxalate stones. The increased presence of zinc and potassium in urine may accelerate the formation of calcium phosphate calculi. Full article

Background/Aim: Appropriate dietary assessment plays a crucial role in individualized nutritional therapy for individuals with type 2 diabetes mellitus (T2DM). Daily dietary variations must be considered in the estimation of usual dietary intake, and such data are limited in individuals with T2DM. This study aimed to evaluate within- and between-individual variations in protein, sodium, potassium, and phosphorus intakes estimated from 24 h urine collection (24 h UC) and semi-weighted dietary records (DRs) in Japanese individuals with T2DM. Methods: This study included 39 Japanese individuals (26 males, 13 females; mean age 64.6 years) with T2DM who attended two hospitals. Protein, sodium, potassium, and phosphorus intakes were estimated using 2-day 24 h UC and 3-day DRs and within- and between-individual variations were calculated using a one-way analysis of variance. Results: The mean protein, potassium, and phosphorus intakes did not significantly differ between 24 h UC and DRs. However, sodium intake was lower when estimated by DRs than by 24 h UC. The coefficients of within-individual variation (CV_w) differed between 24 h UC and DRs. For protein and phosphorus, the CV_w values were smaller by 12.5% and 8.0% in males and 2.3% and 3.0% in females, respectively, for 24 h UC than DRs. For sodium and potassium, the CV_w values were smaller by 7.0% and 4.8% in males, but larger by 5.0% and 3.3% in females, respectively, for 24 h UC than DRs. Conclusions: Our findings demonstrated that 24 h UC showed smaller within-individual variations than DRs for protein and phosphorus in both sexes, with sex-specific differences for sodium and potassium. Full article

Gitelman syndrome (GS) is a rare autosomal recessive renal tubulopathy characterized by hypokalemic metabolic alkalosis, hypomagnesemia, and hypocalciuria due to mutations in the SLC12A3 gene. This case report presents a 54-year-old African American female with near syncope and palpitations. The patient had a history of intermittent palpitations and generalized anxiety disorder and was previously diagnosed with GS. On presentation, the patient exhibited symptoms of severe hypokalemia and hypomagnesemia, attributed to medication non-adherence. Laboratory tests confirmed critically low potassium and magnesium levels, with elevated urine sodium and chloride. Treatment was initiated with oral and intravenous potassium and magnesium, leading to the normalization of electrolyte levels. This case highlights the challenges of managing GS, particularly in patients facing socioeconomic barriers that impede medication adherence and healthcare access. Personalized patient education, combined with comprehensive healthcare resources, is essential to mitigate complications and improve long-term outcomes in such cases. Full article

Diuretics are a class of pharmacological agents that promote the renal excretion of water and electrolytes, increasing urine output and reducing fluid retention. They play a critical role in the management of edematous syndromes, irrespective of their etiology (cardiac, renal, or hepatic), as well as in the treatment of hypertension (HTA). The mechanism of action of diuretics can be classified as either renal, as seen with saluretic diuretics that inhibit sodium and water reabsorption at various segments of the nephron, or extrarenal, involving alterations in the glomerular filtration pressure or osmotic mechanisms. Based on their site of action and mechanism, diuretics are categorized into multiple classes, including loop diuretics, thiazide and thiazide-like diuretics, potassium-sparing diuretics, carbonic anhydrase inhibitors, and osmotic diuretics. These agents are frequently used in combination with other antihypertensive or heart failure medications to optimize therapeutic efficacy. By reducing the blood volume and peripheral vascular resistance, diuretics improve cardiac function, lower blood pressure, and enhance exercise tolerance. Additionally, they are employed in managing chronic kidney disease (CKD), electrolyte imbalances, and specific metabolic disorders. Given the potential for adverse effects such as electrolyte disturbances and renal dysfunction, diuretic therapy should be individualized, with the careful monitoring of the dosage, patient response, and comorbid conditions. Patient education on adherence, lifestyle modifications, and the recognition of side effects is essential for optimizing the therapeutic outcomes and minimizing the risks associated with diuretic therapy. Full article

Maintaining optimal hydration is critical for physiological function, particularly during intense physical activities, in which dehydration or overhydration can impair performance and recovery. Traditional methods for monitoring hydration status, such as body weight changes, bioelectrical impedance, and urine specific gravity, are limited by inconvenience and lack of real-time capability. This study introduces a novel graphene-based dual-sensing electrochemical sensor for the rapid and non-invasive quantification of sodium and potassium concentrations in human sweat, key biomarkers of hydration status. Leveraging graphene’s exceptional conductivity and functionalization potential, the sensor employs open-circuit potentiometry (OCP) to achieve high sensitivity and selectivity in detecting sodium and potassium. The sensor performance was validated against that of a commercial analyzer and ICP-OES, demonstrating a near-Nernstian response (61.93 mV/decade for sodium and 61.21 mV/decade for potassium detection) and a linear detection range spanning from 0.1 mM to 100 mM for both sodium and potassium monitoring in sweat. Sweat samples from an athlete during endurance exercise confirmed the sensor’s reliability, with results closely matching those of ICP-OES and outperforming the commercial analyzer in regards to accuracy and sample efficiency. This work represents a cross-validated study of a sweat-based sensor with a second analytical technique, highlighting its potential as a real-time hydration monitoring tool for use in sports and beyond. Full article

Systemic hypertension is a major global health concern, significantly contributing to the risk of cardiovascular, cerebrovascular, and renal diseases. Antihypertensive medications play a crucial role in lowering blood pressure, with diuretics serving as a particularly effective first-line therapy. However, the development of new compounds with diuretic properties, renal protective effects, and unique mechanisms of action remains a critical area of research for improving clinical outcomes. In this context, the present study investigated the diuretic and renal protective potential of the citrus flavonoid hesperidin in rats. Male spontaneously hypertensive and normotensive rats were treated with hesperidin at a dose of 3.0 mg/kg daily for seven days. Urine samples were analyzed for electrolytes (Na⁺, K⁺, Cl⁻, and Ca²⁺), biochemical parameters, and crystal precipitation, while renal tissues were examined histologically. Hesperidin treatment resulted in significant diuretic and natriuretic effects, along with potassium- and calcium-sparing properties. Furthermore, a marked reduction in calcium oxalate crystal formation was observed in the hesperidin-treated group. Histological analysis indicated a protective effect on renal tissue, with structural preservation observed in hypertensive rats. Docking studies revealed that hesperetin, the active metabolite of hesperidin formed upon oral administration, exhibited a high binding affinity for the calcium-sensing receptor (CaSR). This hypothesis may explain its role in preventing urinary crystalluria and contributing to calcium-sparing effects. Full article

Background and Objectives: Brain natriuretic peptide (NT-proBNP) is a biomarker widely used in diagnosing and monitoring heart failure. Its impact on electrolyte homeostasis is known, particularly for sodium. However, its relationship with serum calcium remains unclear. This retrospective observational study aimed to investigate the longitudinal association between NT-proBNP and serum calcium levels in a cohort of hospitalized patients with the goal of determining whether NT-proBNP could have a direct or indirect impact on calcium metabolism. Materials and Methods: We included 688 patients with 1022 repeated measurements of NT-proBNP and serum calcium collected during hospitalization from March 2022 to February 2025. Linear mixed models (LMMs) were employed to analyze longitudinal associations, adjusting for age, eGFR, estimated plasma volume status (ePVs), CRP, potassium, and albumin. Results: Baseline analysis revealed a negative correlation between NT-proBNP and serum calcium (r = −0.23, p < 0.001). Univariate LMM demonstrated a significant negative association (β = −1.3 × 10⁻⁵, p < 0.001), which remained significant in multivariate analysis (β = −6.9 × 10⁻⁶, p = 0.01), accounting for intrasubject variability. This suggests that as NT-proBNP increases, serum calcium levels decrease within individual patients, independent of confounders. This study’s findings indicate that NT-proBNP may influence calcium excretion, possibly through mechanisms involving the sodium–calcium exchanger (NCX) in renal tubules, similar to its effects on sodium homeostasis. Conclusions: This is the first study to evaluate the longitudinal impact of NT-proBNP on serum calcium, highlighting a potential clinical relevance in patients with cardiac dysfunction. Limitations include a retrospective design and a lack of urine calcium data. Further research is warranted to validate these findings and elucidate the underlying mechanisms. Full article