Racial differences in potassium homeostasis in response to differences in dietary sodium in girls123

PubMed Central

Wigertz, Karin; Martin, Berdine R; Braun, Michelle; Pratt, J Howard; Peacock, Munro; Weaver, Connie M

2010-01-01

Background: Racial differences in the renal disposition of potassium may be related to mechanisms for the greater susceptibility to hypertension in blacks than in whites. Objective: Our objective was to study the racial differences in the renin-angiotensin-aldosterone system and in potassium balance in black and white girls consuming a controlled diet that was low in potassium with 2 amounts of sodium intake (low compared with high). Design: The studies reported here were performed in 40 black and 28 white girls, aged 11–15 y, under highly controlled metabolic conditions. The studies comprised 2 sessions of 20-d metabolic balance sessions, at 2 amounts of dietary sodium intake (58 and 170 mmol · L−1 · d−1), in a crossover design and with a constant dietary potassium intake of 50 mmol · L−1 · d−1. Repeated-measures analysis of variance was used to test for racial differences in potassium output and retention by sodium intakes. Results: Thirty black and 20 white girls completed the study. Urinary potassium excretion was lower in blacks than in whites, regardless of sodium intake (P < 0.05), with no differences in fecal or sweat potassium excretion. Cumulative potassium retention was significantly higher in blacks while consuming the low sodium diet. Plasma aldosterone concentrations after upright posture were significantly lower in blacks than in whites but were similar when supine, as were urinary aldosterone excretion rates. On week 3, blood pressure, body weight, urinary volume, creatinine, and serum sodium and potassium were similar. Conclusion: The well-known racial difference in urinary potassium excretion appears to be at least in part due to greater renal retention of potassium in black girls. PMID:20007307

Sodium and potassium urinary excretion and their ratio in the elderly: results from the Nutrition UP 65 study

PubMed Central

Moreira, Pedro; Sousa, Ana S.; Guerra, Rita S.; Santos, Alejandro; Borges, Nuno; Afonso, Cláudia; Amaral, Teresa F.; Padrão, Patrícia

2018-01-01

Background We aimed to describe urinary sodium and potassium excretion and their ratio in a representative sample of Portuguese elderly population, according to sociodemographic characteristics and weight status. Methods A cluster sampling approach was used, representing older Portuguese adults (≥65 years) according to age, sex, education level, and regional area within the Nutrition UP 65 study. This cross-sectional evaluation was conducted in 2015 and 2016. From a sample size of 1,500 participants, 1,318 were eligible for the present analysis, 57.3% were women, and 23.5% were aged ≥80 years. Sodium and potassium consumption was evaluated through one 24 h urinary excretion. Inadequate sodium intake was defined as ≥2,000 mg/day, inadequate potassium intake was considered as <3,510 mg/day, and inadequate sodium-to-potassium ratio was defined as >1, according to the World Health Organization cutoffs. Results The proportion of the participants with an inadequate intake was 80.0% in women and 91.5% in men (sodium), 96.2% of women and 79.4% of men (potassium), and 98.4% of women and 99.1% of men (sodium-to-potassium ratio). Higher sodium adequacy was observed among the older elderly, unmarried, with lower household income, and underweight/normal weight. Higher potassium adequacy was observed in the younger elderly, married, and with higher income. Conclusion The majority of the Portuguese elderly population was classified as having inadequate sodium, potassium, and sodium-to-potassium ratio urinary excretion. Therefore, strategies for reducing sodium and increasing potassium intake are priorities in the Portuguese elderly population. PMID:29545733

Effectiveness of a Self-monitoring Device for Urinary Sodium-to-Potassium Ratio on Dietary Improvement in Free-Living Adults: a Randomized Controlled Trial.

PubMed

Iwahori, Toshiyuki; Ueshima, Hirotsugu; Ohgami, Naoto; Yamashita, Hideyuki; Miyagawa, Naoko; Kondo, Keiko; Torii, Sayuki; Yoshita, Katsushi; Shiga, Toshikazu; Ohkubo, Takayoshi; Arima, Hisatomi; Miura, Katsuyuki

2018-01-05

Reducing the urinary sodium-to-potassium ratio is important for reducing both blood pressure and risk of cardiovascular disease. Among free-living Japanese individuals, we carried out a randomized trial to clarify the effect of lifestyle modification for lowering urinary sodium-to-potassium ratio using a self-monitoring device. This was an open, prospective, parallel randomized, controlled trial. Ninety-two individuals were recruited from Japanese volunteers. Participants were randomly allocated into intervention and control groups. A month-long dietary intervention on self-monitoring urinary sodium-to-potassium ratio was carried out using monitors (HEU-001F, OMRON Healthcare Co., Ltd., Kyoto, Japan). All participants had brief dietary education and received a leaflet as usual care. Monitors were handed out to the intervention group, but not to the control group. The intervention group was asked to measure at least one spot urine sodium-to-potassium ratio daily, and advised to lower their sodium-to-potassium ratio toward the target of less than 1. Outcomes included changes in 24-hour urinary sodium-to-potassium ratio, sodium excretion, potassium excretion, blood pressure, and body weight in both groups. Mean measurement frequency of monitoring was 2.8 times/day during the intervention. Changes in urinary sodium-to-potassium ratio were -0.55 in the intervention group and -0.06 in the control group (P = 0.088); respective sodium excretion changes were -18.5 mmol/24 hours and -8.7 mmol/24 hours (P = 0.528); and corresponding potassium excretion was 2.6 mmol/24 hours and -1.5 mmol/24 hours (P = 0.300). No significant reductions were observed in either blood pressure or body weight after the intervention. Providing the device to self-monitor a sodium-to-potassium ratio did not achieve the targeted reduction of the ratio in "pure self-management" settings, indicating further needs to study an effective method to enhance the synergetic effect of dietary programs and self-monitoring practice to achieve the reduction. However, we cannot deny the possibility of reducing sodium-to-potassium ratio using a self-monitoring device.

Sodium in the Finnish diet: 20-year trends in urinary sodium excretion among the adult population.

PubMed

Laatikainen, T; Pietinen, P; Valsta, L; Sundvall, J; Reinivuo, H; Tuomilehto, J

2006-08-01

High sodium intake increases the risk of cardiovascular diseases and may also be associated with higher rates of stomach cancer, asthma disorders and infections. In Finland, cross-sectional population surveys to monitor cardiovascular risk factors have been carried out since the 1970s. The main aim of this paper is to present trends in urinary sodium and potassium excretion from 1979 to 2002. Cross-sectional population surveys on cardiovascular risk factors. Surveys were carried out in Finland in 1979, 1982, 1987 and 2002 in four geographical areas: North Karelia, the Kuopio area, Southwestern Finland and the Helsinki area. For each survey a random sample stratified by age and sex was drawn from the population register. In this analysis, participants of urine collection subsamples aged 25-64 years (n = 4648) were included. A 24-h urinary collection was carried out in subsamples (n = 2218-2487) in connection with population risk factor surveys. Urinary sodium and potassium concentrations were analyzed in the same laboratory throughout, using a flame photometer in 1979, 1982 and 1987 and an ion-selective electrode in 2002. Between 1979 and 2002 urinary sodium excretion in Finland decreased from over 220 to less than 170 mmol/day among men and from nearly 180 to less than 130 mmol/day among women. Although potassium excretion decreased somewhat as well, the decrease in sodium-potassium molar ratio was also significant. The 24-h urinary sodium excretion in Finland has decreased significantly during the last 20 years. However, excretion levels are still considerably higher than recommendations. A further decrease in sodium intake remains a goal for the Finnish food industry and consumers. All surveys were funded by the National Public Health Institute in Finland.

Renal function in sheep during infusion of alkali metal ions into the renal artery.

PubMed Central

Beal, A M; Harrison, F A

1975-01-01

1. The effect on renal function of 1 M solutions of LiCl, NaCl, KCl, RbCl and CsCl and 3 M-NaCl infused close-arterially to the kidney for 10 min at 0-7ml./min has been studied in nine experiments on four unilaterally nephrectomized sheep. The levels of flow, electrolyte concentration and electrolyte excretion in the urine were measured before, during and for 50 min after the infusions. 2. The infusion of 1-M-NaCl produced little change in urine flow and composition whereas 3 M-NaCl resulted in relatively small increases in urine flow and sodium excretion. 3. The infusion of lithium, potassium, rubidium and caesium resulted in marked increases in urine flow, urinary sodium concentration and excretion, urinary potassium excretion and osmolal clearance while the urinary potassium concentration decreased. 4. Changes in urine flow and urinary pH during the infusions of all the alkali ions except sodium were consistent with increased urinary bicarbonate excretion. 5. The osmolal clearance was increased by the infusion of lithium, potassium, rubidium and caesium, but equivalent increases in the rate of solutefree water reabsorption did not occur. 6. The infusion of caesium resulted in a depression of the glomerular filtration rate (G.F.R.) which was not observed when the other alkali ions were infused. 7. The effects of lithium, potassium and rubidium on urine flow and composition were rapid in onset and the residual effects on these ions, on cessation of infusion, were relatively short. The effects on caesium were slow in onset and prolonged in duration. 8. It was concluded that lithium, potassium, rubidium, and caesium altered urine flow and electrolyte excretion by acting upon common mechanisms which were predominantly intra-renal and located in the proximal segment of the nephron. PMID:236381

Assessment of Dietary Sodium and Potassium in Canadians Using 24-Hour Urinary Collection.

PubMed

Mente, Andrew; Dagenais, Gilles; Wielgosz, Andreas; Lear, Scott A; McQueen, Matthew J; Zeidler, Johannes; Fu, Lily; DeJesus, Jane; Rangarajan, Sumathy; Bourlaud, Anne-Sophie; De Bluts, Anne Leblanc; Corber, Erica; de Jong, Veronica; Boomgaardt, Jacob; Shane, Alexandra; Jiang, Ying; de Groh, Margaret; O'Donnell, Martin J; Yusuf, Salim; Teo, Koon

2016-03-01

Although salt intake derived from data on urinary sodium excretion in free-living populations has been used in public policy, a population study on urinary sodium excretion has not been done in Canada. We assessed dietary sodium and potassium intake using a 24-hour urine collection in a large survey of urban and rural communities from 4 Canadian cities and determined the association of these electrolytes with blood pressure (BP). One thousand seven hundred consecutive individuals, aged 37-72 years, attending their annual follow-up visits of the ongoing Prospective and Urban Rural Epidemiology (PURE) study in Vancouver, Hamilton, Ottawa, and Quebec City, Canada, collected a 24-hour urine sample using standardized procedures. Mean sodium excretion was 3325 mg/d and mean potassium excretion was 2935 mg/d. Sodium excretion ranged from 3093 mg/d in Vancouver to 3642 mg/d in Quebec City, after adjusting for covariates. Potassium excretion ranged from 2844 mg/d in Ottawa to 3082 mg/d in Quebec City. Both electrolytes were higher in men than in women and in rural populations than in urban settings (P < 0.001 for all). Sodium excretion was between 3000 and 6000 mg/d in 48.3% of the participants, < 3000 mg/d in 46.7%, and > 6000 mg/d in only 5%. No significant association between sodium or potassium excretion and BP was found. Sodium consumption in these Canadians is within a range comparable to other Western countries, and intake in most individuals is < 6000 mg/d, with only 5% at higher levels. Within this range, sodium or potassium levels were not associated with BP. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Effect of salt intake and potassium supplementation on urinary renalase and serum dopamine levels in Chinese adults.

PubMed

Wang, Yang; Wang, Dan; Chu, Chao; Mu, Jian-Jun; Wang, Man; Liu, Fu-Qiang; Xie, Bing-Qing; Yang, Fan; Dong, Zhen-Zhen; Yuan, Zu-Yi

2015-01-01

The aim of our study was to assess the effects of altered salt and potassium intake on urinary renalase and serum dopamine levels in humans. Forty-two subjects (28–65 years of age) were selected from a rural community of northern China. All subjects were sequentially maintained on a low-salt diet for 7 days (3.0 g/day of NaCl), a high-salt diet for an additional 7 days (18.0 g/day of NaCl), and a high-salt diet with potassium supplementation for a final 7 days (18.0 g/day of NaCl + 4.5 g/day of KCl). Urinary renalase excretions were significantly higher during the high-salt diet intervention than during the low-salt diet. During high-potassium intake, urinary renalase excretions were not significantly different from the high-salt diet, whereas they were significantly higher than the low-salt levels. Serum dopamine levels exhibited similar trends across the interventions. Additionally, a significant positive relationship was observed between the urine renalase and serum dopamine among the different dietary interventions. Also, 24-hour urinary sodium excretion positively correlated with urine renalase and serum dopamine in the whole population. The present study indicates that dietary salt intake and potassium supplementation increase urinary renalase and serum dopamine levels in Chinese subjects. © 2015 S. Karger AG, Basel

Urinary potassium excretion and risk of developing hypertension: the prevention of renal and vascular end-stage disease study.

PubMed

Kieneker, Lyanne M; Gansevoort, Ron T; Mukamal, Kenneth J; de Boer, Rudolf A; Navis, Gerjan; Bakker, Stephan J L; Joosten, Michel M

2014-10-01

Previous prospective cohort studies on the association between potassium intake and risk of hypertension have almost exclusively relied on self-reported dietary data, whereas repeated 24-hour urine excretions, as estimate of dietary uptake, may provide a more objective and quantitative estimate of this association. Risk of hypertension (defined as blood pressure ≥140/90 mm Hg or initiation of blood pressure-lowering drugs) was prospectively studied in 5511 normotensive subjects aged 28 to 75 years not using blood pressure-lowering drugs at baseline of the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study. Potassium excretion was measured in two 24-hour urine specimens at baseline (1997-1998) and midway during follow-up (2001-2003). Baseline median potassium excretion was 70 mmol/24 h (interquartile range, 57-85 mmol/24 h), which corresponds to a dietary potassium intake of ≈91 mmol/24 h. During a median follow-up of 7.6 years (interquartile range, 5.0-9.3 years), 1172 subjects developed hypertension. The lowest sex-specific tertile of potassium excretion (men: <68 mmol/24 h; women: <58 mmol/24 h) had an increased risk of hypertension after multivariable adjustment (hazard ratio, 1.20; 95% confidence interval, 1.05-1.37), compared with the upper 2 tertiles (Pnonlinearity=0.008). The proportion of hypertension attributable to low potassium excretion was 6.2% (95% confidence interval, 1.7%-10.9%). No association was found between the sodium to potassium excretion ratio and risk of hypertension after multivariable adjustment. Low urinary potassium excretion was associated with an increased risk of developing hypertension. Dietary strategies to increase potassium intake to the recommended level of 90 mmol/d may have the potential to reduce the incidence of hypertension. © 2014 American Heart Association, Inc.

Influence of injected caffeine on the metabolism of calcium and the retention and excretion of sodium, potassium, phosphorus, magnesium, zinc and copper in rats.

PubMed

Yeh, J K; Aloia, J F; Semla, H M; Chen, S Y

1986-02-01

Mineral metabolism was studied by the metabolic balance technique in rats with and without administration of caffeine. Caffeine was injected subcutaneously each day at either 2.5 mg or 10 mg/100 g body weight for 2 wk before the balance studies. Urinary volume excretion was higher in the group given caffeine than in the control group, but the creatinine clearance was not different. Urinary excretion of potassium, sodium, inorganic phosphate, magnesium and calcium, but not of zinc and copper, was also higher in the rats given caffeine. The rank order of the difference was the same as the percent of ingested mineral excreted in urine in the absence of caffeine. Caffeine caused a negative balance of potassium, sodium and inorganic phosphate. There was no significant difference from the control levels and in the apparent metabolic balance of calcium and magnesium. The urinary and fecal excretion of zinc and copper were found to be unaffected by caffeine. It is suggested that chronic administration of caffeine may lead to a tendency toward deficiency of those minerals that are excreted primarily in urine.

Potassium urinary excretion and dietary intake: a cross-sectional analysis in 8-10 year-old children.

PubMed

Oliveira, Ana Catarina; Padrão, Patrícia; Moreira, André; Pinto, Mariana; Neto, Mafalda; Santos, Tânia; Madureira, Joana; Fernandes, Eduardo de Oliveira; Graça, Pedro; Breda, João; Moreira, Pedro

2015-05-17

Data from studies assessing the intake of potassium, and the concomitant sodium-to-potassium ratio are limited. The aim of this study was to evaluate potassium and sodium-to-potassium ratio intake in 8-10 year-old children. A cross-sectional survey was carried out from January to June 2014 and data from 163 children (81 boys) were included. Potassium intake was estimated by 24-h urine collection and coefficient of creatinine was used to validate completeness of urine collections. Urinary sodium and sodium-to-potassium ratio were also analysed. A 24-h dietary recall was used to provide information on dietary sources of potassium. Height and weight were measured according to international standards. The mean urinary potassium excretion was 1701 ± 594 mg/day in boys, and 1682 ± 541 mg/day in girls (p = 0.835); 8.0% of children met the WHO recommendations for potassium intake. The mean sodium excretion was 2935 ± 1075 mg/day in boys and 2381 ± 1045 mg/day in girls (p <0.001) and urinary sodium-to-potassium ratio was 3.2 ± 1.4 in boys, and 2.5 ± 1.1 in girls (p = 0.002). The mean fruit and vegetable intake was 353.1 ± 232.5 g/day in boys, and 290.8 ± 213.1 g/day in girls (p = 0.101). This study reported a low compliance of potassium intake recommendations in 8-10 year-old children. Health promotion interventions are needed in order to broaden public awareness of potassium inadequacy and to increase potassium intake.

Effectiveness of a Self-monitoring Device for Urinary Sodium-to-Potassium Ratio on Dietary Improvement in Free-Living Adults: a Randomized Controlled Trial

PubMed Central

Ueshima, Hirotsugu; Ohgami, Naoto; Yamashita, Hideyuki; Miyagawa, Naoko; Kondo, Keiko; Torii, Sayuki; Yoshita, Katsushi; Shiga, Toshikazu; Ohkubo, Takayoshi; Arima, Hisatomi; Miura, Katsuyuki

2018-01-01

Background Reducing the urinary sodium-to-potassium ratio is important for reducing both blood pressure and risk of cardiovascular disease. Among free-living Japanese individuals, we carried out a randomized trial to clarify the effect of lifestyle modification for lowering urinary sodium-to-potassium ratio using a self-monitoring device. Methods This was an open, prospective, parallel randomized, controlled trial. Ninety-two individuals were recruited from Japanese volunteers. Participants were randomly allocated into intervention and control groups. A month-long dietary intervention on self-monitoring urinary sodium-to-potassium ratio was carried out using monitors (HEU-001F, OMRON Healthcare Co., Ltd., Kyoto, Japan). All participants had brief dietary education and received a leaflet as usual care. Monitors were handed out to the intervention group, but not to the control group. The intervention group was asked to measure at least one spot urine sodium-to-potassium ratio daily, and advised to lower their sodium-to-potassium ratio toward the target of less than 1. Outcomes included changes in 24-hour urinary sodium-to-potassium ratio, sodium excretion, potassium excretion, blood pressure, and body weight in both groups. Results Mean measurement frequency of monitoring was 2.8 times/day during the intervention. Changes in urinary sodium-to-potassium ratio were −0.55 in the intervention group and −0.06 in the control group (P = 0.088); respective sodium excretion changes were −18.5 mmol/24 hours and −8.7 mmol/24 hours (P = 0.528); and corresponding potassium excretion was 2.6 mmol/24 hours and −1.5 mmol/24 hours (P = 0.300). No significant reductions were observed in either blood pressure or body weight after the intervention. Conclusions Providing the device to self-monitor a sodium-to-potassium ratio did not achieve the targeted reduction of the ratio in “pure self-management” settings, indicating further needs to study an effective method to enhance the synergetic effect of dietary programs and self-monitoring practice to achieve the reduction. However, we cannot deny the possibility of reducing sodium-to-potassium ratio using a self-monitoring device. PMID:29093302

Increasing alkali supplementation decreases urinary nitrogen excretion when adjusted for same day nitrogen intake

USDA-ARS?s Scientific Manuscript database

Summary: We examined whether escalating doses of potassium bicarbonate (KHCO3) supplements alter urinary nitrogen excretion expressed as a ratio to same day nitrogen intake (measure of muscle-protein breakdown). The ratio declined significantly from placebo to low to high dose of KHCO3 supplementati...

In vivo measurement of human body composition

NASA Technical Reports Server (NTRS)

Pace, N.; Grunbaum, B. W.; Kodama, A. M.; Price, D. C.

1974-01-01

The female bed rest study has shown that, the response of women to prolonged recumbency of 2 to 3 weeks duration is very similar to that displayed by men. Some of the key findings in the women after 17 days of continuous recumbency are: (1) a decrease in plasma volume of 12-13 per cent; (2) a small decrease in total body water; (3) a decrease in total body potassium of 3 to 4 per cent; (4) a decrease in plasma potassium concentration of 4 to 5 per cent; (5) a decrease in total circulating plasma protein of 11 to 12 per cent; (6) a decrease in urinary norepinephrine excretion rate of 27 to 28 per cent; (7) a possible increase in urinary magnesium, calcium, and phosphate excretion rates; and (8) a possible increase in urinary citrate excretion rate.

Validity of a self-administered food frequency questionnaire in the 5-year follow-up survey of the JPHC Study Cohort I to assess sodium and potassium intake: comparison with dietary records and 24-hour urinary excretion level.

PubMed

Sasaki, Satoshi; Ishihara, Junko; Tsugane, Shoichiro

2003-01-01

We compared the intake levels of sodium and potassium assessed with a self-administered semi-quantitative food frequency questionnaire (FFQ) used in a 5-year follow-up survey of the JPHC study and 28-day dietary record (DR), and the corresponding two 24-hour urinary excretion levels (32 men and 57 women) in 3-areas, i.e., Ninohe, Yokote, and Saku Public Health Center areas. The Spearman rank correlation coefficients between dietary sodium assessed with FFQ and the urinary excretion for crude values were 0.24 and -0.10 in men and women, respectively. After adjusting for energy and creatinine, the sodium correlation coefficients were 0.35 and 0.25 in men and women, respectively. The correlation coefficients for crude potassium values were 0.18 and -0.13 in men and women, respectively. After adjusting for energy and creatinine, the potassium correlation coefficients were 0.48 and 0.18 in men and women, respectively in conclusion, a weak correlation was observed both for sodium and potassium after energy and creatinine adjustment in men, whereas no meaningful correlation was observed in women.

Urinary Sodium and Potassium Excretion and Carotid Atherosclerosis in Chinese Men and Women

PubMed Central

Dai, Xiao-Wei; Wang, Cheng; Xu, Ying; Guan, Ke; Su, Yi-Xiang; Chen, Yu-Ming

2016-01-01

Limited studies have examined the association between sodium (Na) and potassium (K) levels and the risk of atherosclerosis. This study examined whether higher Na and Na/K levels and low K levels were independent risk factors for atherosclerosis. This community-based cross-sectional study included 3290 subjects (1067 men and 2223 women) 40 to 75 years of age in Guangzhou, China, between 2011 and 2013. Urinary excretion of Na and K were measured from the first morning void, and creatinine-adjusted values were used. The intima-media thickness (IMT) of the carotid common artery and the carotid bifurcation was measured with high-resolution B-mode ultrasonography. Dietary K and Na intake and other covariates were obtained by face-to-face interviews. A significant positive association was seen between urinary Na excretion and carotid atherosclerosis after adjustment for age, sex, and other lifestyle covariates. The odds ratios (OR) and 95% confidence interval (CI) of the highest (vs. lowest) quartile of urinary Na were 1.32 (1.04–1.66) for carotid plaques, 1.48 (1.18–1.87) for increased common carotid artery IMT, and 1.55 (1.23–1.96) for increased carotid bifurcation IMT (all p-trend < 0.01). A similar positive association was observed between urinary Na/K levels and carotid plaque and increased IMT, and between dietary Na intake and increased bifurcation IMT. Regarding potassium data, we only found a significantly lower presence of carotid plaque (OR 0.72, 95% CI 0.57–0.91) for quartile 2 (vs. 1) of urinary K. Our findings suggest that higher levels of urinary excretion Na and Na/K are significantly associated with greater presence of carotid atherosclerosis in Chinese adults. PMID:27706075

Mechanism of Action and Pharmacology of Patiromer, a Nonabsorbed Cross-Linked Polymer That Lowers Serum Potassium Concentration in Patients With Hyperkalemia.

PubMed

Li, Lingyun; Harrison, Stephen D; Cope, M Jamie; Park, Craig; Lee, Lawrence; Salaymeh, Faleh; Madsen, Deidre; Benton, Wade W; Berman, Lance; Buysse, Jerry

2016-09-01

Hyperkalemia is a potentially life-threatening condition, and patients who have chronic kidney disease, who are diabetic, or who are taking renin-angiotensin-aldosterone system inhibitors are at increased risk. Therapeutic options for hyperkalemia tend to have limited effectiveness and can be associated with serious side effects. Colonic potassium secretion can increase to compensate when urinary potassium excretion decreases in patients with renal impairment, but this adaptation is insufficient and hyperkalemia still results. Patiromer is a novel, spherical, nonabsorbed polymer designed to bind and remove potassium, primarily in the colon, thereby decreasing serum potassium in patients with hyperkalemia. Patiromer has been found to decrease serum potassium in patients with hyperkalemia having chronic kidney disease who were on renin-angiotensin-aldosterone system inhibitors. Results of nonclinical studies and an early phase clinical study are reported here. Two studies with radiolabeled drug, one in rats and the other in dogs, confirmed that patiromer was not absorbed into the systemic circulation. Results of an in vitro study showed that patiromer was able to bind 8.5 to 8.8 mEq of potassium per gram of polymer at a pH similar to that found in the colon and had a much higher potassium-binding capacity compared with other resins, including polystyrene sulfonate. In a study in hyperkalemic rats, a decrease in serum potassium was observed via an increase in fecal potassium excretion. In a clinical study in healthy adult volunteers, a significant increase in fecal potassium excretion and a significant decrease in urinary potassium excretion were observed. Overall, patiromer is a high-capacity potassium binder, and the chemical and physical characteristics of patiromer may lead to good clinical efficacy, tolerability, and patient acceptance. © The Author(s) 2016.

Mechanism of Action and Pharmacology of Patiromer, a Nonabsorbed Cross-Linked Polymer That Lowers Serum Potassium Concentration in Patients With Hyperkalemia

PubMed Central

Harrison, Stephen D.; Cope, M. Jamie; Park, Craig; Lee, Lawrence; Salaymeh, Faleh; Madsen, Deidre; Benton, Wade W.; Berman, Lance; Buysse, Jerry

2016-01-01

Hyperkalemia is a potentially life-threatening condition, and patients who have chronic kidney disease, who are diabetic, or who are taking renin–angiotensin–aldosterone system inhibitors are at increased risk. Therapeutic options for hyperkalemia tend to have limited effectiveness and can be associated with serious side effects. Colonic potassium secretion can increase to compensate when urinary potassium excretion decreases in patients with renal impairment, but this adaptation is insufficient and hyperkalemia still results. Patiromer is a novel, spherical, nonabsorbed polymer designed to bind and remove potassium, primarily in the colon, thereby decreasing serum potassium in patients with hyperkalemia. Patiromer has been found to decrease serum potassium in patients with hyperkalemia having chronic kidney disease who were on renin–angiotensin–aldosterone system inhibitors. Results of nonclinical studies and an early phase clinical study are reported here. Two studies with radiolabeled drug, one in rats and the other in dogs, confirmed that patiromer was not absorbed into the systemic circulation. Results of an in vitro study showed that patiromer was able to bind 8.5 to 8.8 mEq of potassium per gram of polymer at a pH similar to that found in the colon and had a much higher potassium-binding capacity compared with other resins, including polystyrene sulfonate. In a study in hyperkalemic rats, a decrease in serum potassium was observed via an increase in fecal potassium excretion. In a clinical study in healthy adult volunteers, a significant increase in fecal potassium excretion and a significant decrease in urinary potassium excretion were observed. Overall, patiromer is a high-capacity potassium binder, and the chemical and physical characteristics of patiromer may lead to good clinical efficacy, tolerability, and patient acceptance. PMID:26856345

The salt-taste threshold in untreated hypertensive patients.

PubMed

Kim, Chang-Yeon; Ye, Mi-Kyung; Lee, Young Soo

2017-01-01

The salt-taste threshold can influence the salt appetite, and is thought to be another marker of sodium intake. Many studies have mentioned the relationship between the sodium intake and blood pressure (BP). The aim of this study was to evaluate the relationship between the salt-taste threshold and urinary sodium excretion in normotensive and hypertensive groups. We analyzed 199 patients (mean age 52 years, male 47.3%) who underwent 24-h ambulatory BP monitoring (ABPM). Hypertension was diagnosed as an average daytime systolic BP of ≥135 mmHg or diastolic BP of ≥85 mmHg by the ABPM. We assessed the salt-taste threshold using graded saline solutions. The salt-taste threshold, 24-h urinary sodium and potassium excretion, and echocardiographic data were compared between the control and hypertensive groups. The detection and recognition threshold of the salt taste did not significantly differ between the control and hypertensive groups. The 24-h urinary sodium excretion of hypertensive patients was significantly higher than that of the control group (140.9 ± 59.8 vs. 117.9 ± 57.2 mEq/day, respectively, p  = 0.011). Also, the urinary sodium-potassium ratio was significantly higher in the hypertensive patients. There was no correlation between the salt-taste threshold and 24-h urinary sodium excretion. The salt-taste threshold might not be related to the BP status as well as the 24-h urinary sodium excretion.

Evaluation of the Pharmacodynamic Effects of the Potassium Binder RDX7675 in Mice.

PubMed

Davidson, James P; King, Andrew J; Kumaraswamy, Padmapriya; Caldwell, Jeremy S; Korner, Paul; Blanks, Robert C; Jacobs, Jeffrey W

2018-05-01

Hyperkalemia is a common complication in patients with heart failure or chronic kidney disease, particularly those who are taking inhibitors of the renin-angiotensin-aldosterone system. RDX7675, the calcium salt of a reengineered polystyrene sulfonate-based resin, is a potassium binder that is being investigated as a novel treatment for hyperkalemia. This study evaluated the pharmacodynamic effects of RDX7675 in mice, compared to 2 current treatments, sodium polystyrene sulfonate (SPS) and patiromer. Seven groups of 8 male CD-1 mice were given either standard chow (controls) or standard chow containing 4.0% or 6.6% active moiety of RDX7675, patiromer, or SPS for 72 hours. Stool and urine were collected over the final 24 hours of treatment for ion excretion analyses. RDX7675 increased stool potassium (mean 24-hour excretion: 4.0%, 9.19 mg; 6.6%, 18.11 mg; both P < .0001) compared with controls (4.47 mg) and decreased urinary potassium (mean 24-hour excretion: 4.0%, 12.05 mg, P < .001; 6.6%, 6.68 mg, P < .0001; vs controls, 20.38 mg). The potassium-binding capacity of RDX7675 (stool potassium/gram of resin: 4.0%, 1.14 mEq/g; 6.6%, 1.32 mEq/g) was greater (all P < .0001) than for patiromer (4.0%, 0.63 mEq/g; 6.6%, 0.48 mEq/g) or SPS (4.0%, 0.73 mEq/g; 6.6% 0.55 mEq/g). RDX7675 and patiromer decreased urinary sodium (mean 24-hour excretion: 0.07-1.38 mg; all P < .001) compared to controls (5.01 mg). In contrast, SPS increased urinary sodium excretion (4.0%, 13.31 mg; 6.6%, 17.60 mg; both P < .0001) compared to controls. RDX7675 reduced intestinal potassium absorption and had a greater potassium-binding capacity than patiromer or SPS in mice. The calcium-based resins RDX7675 and patiromer reduced intestinal sodium absorption, unlike sodium-based SPS. These results support further studies in humans to confirm the potential of RDX7675 for the treatment of patients with hyperkalemia.

Assessment of Sodium and Potassium Intake by 24 h Urinary Excretion in a Healthy Mexican Cohort.

PubMed

Vallejo, Maite; Colín-Ramírez, Eloisa; Rivera Mancía, Susana; Cartas Rosado, Raúl; Madero, Magdalena; Infante Vázquez, Oscar; Vargas-Barrón, Jesús

2017-02-01

A high dietary sodium intake and a low potassium intake are associated with adverse cardiovascular health. Data on these nutrients consumption in Mexico is limited. The aim of this study was to assess sodium and potassium intake by 24 h urinary excretion in a clinically healthy Mexican population. We additionally explored their association with blood pressure. 711 clinically healthy participants aged 20-50 years old recruited in the Tlalpan 2020 cohort from September 2014-December 2015, were included in this cross-sectional analysis. All participants provided a 24 h urine sample and underwent anthropometric, biochemical, and blood pressure evaluations. Univariate and multivariate linear regression analyses were used to assess the association of urinary sodium, potassium, and Na/K ratio with blood pressure. Mean (95% confidence interval [CI]) urinary sodium and potassium in the overall population was 3150.1 (3054.2-3246.0) mg/d and 1909.5 (1859.3-1959.6) mg/d, respectively. Overall, only 121 (17%) met the WHO recommendation for sodium intake (<2000 mg/d) and 16 (2.3%) met the goal for potassium intake (≥3510 mg/d). Urinary sodium (β coefficient 1.3, 95% CI: 0.7, 1.8, p <0.001) and potassium (β coefficient 2.1, 95% CI: 1.0, 3.2, p <0.001) were found to be associated with systolic blood pressure in the univariate analysis but not in the multivariate analysis. Sodium intake was higher and potassium intake was lower than the WHO recommendations in this healthy Mexican population. Sodium and potassium intakes were not associated with blood pressure at the mean levels of intake observed in this population, after adjusting for key variables. Copyright © 2017 IMSS. Published by Elsevier Inc. All rights reserved.

Urinary potassium excretion, renal ammoniagenesis, and risk of graft failure and mortality in renal transplant recipients.

PubMed

Eisenga, Michele F; Kieneker, Lyanne M; Soedamah-Muthu, Sabita S; van den Berg, Else; Deetman, Petronella E; Navis, Gerjan J; Gans, Reinold Ob; Gaillard, Carlo Ajm; Bakker, Stephan Jl; Joosten, Michel M

2016-12-01

Renal transplant recipients (RTRs) have commonly been urged to limit their potassium intake during renal insufficiency and may adhere to this principle after transplantation. Importantly, in experimental animal models, low dietary potassium intake induces kidney injury through stimulation of ammoniagenesis. In humans, low potassium intake is an established risk factor for high blood pressure. We hypothesized that low 24-h urinary potassium excretion [UKV; urinary potassium concentration × volume], the gold standard for assessment of dietary potassium intake, represents a risk factor for graft failure and mortality in RTRs. In secondary analyses, we aimed to investigate whether these associations could be explained by ammoniagenesis, plasma potassium, or blood pressure. In a prospective cohort of 705 RTRs, we assessed dietary potassium intake by a single 24-h UKV and food-frequency questionnaires. Cox regression analyses were used to investigate prospective associations with outcome. We included 705 stable RTRs (mean ± SD age: 53 ± 13 y; 57% men) at 5.4 y (IQR: 1.9-12.0 y) after transplantation and 253 kidney donors. Mean ± SD UKV was 73 ± 24 mmol/24 h in RTRs compared with 85 ± 25 mmol/24 h in kidney donors. During follow-up for 3.1 y (IQR: 2.7-3.9 y), 45 RTRs developed graft failure and 83 died. RTRs in the lowest sex-specific tertile of UKV (women, <55 mmol/24 h; men, <65 mmol/24 h) had an increased risk of graft failure (HR: 3.70; 95% CI: 1.64, 8.34) and risk of mortality (HR; 2.66; 95% CI: 1.53, 4.61), independent of potential confounders. In causal path analyses, 24-h urinary ammonia excretion, plasma potassium, and blood pressure did not affect these associations. Our results indicate that low UKV is associated with a higher risk of graft failure and mortality in RTRs. Specific attention for adequate potassium intake after transplantation seems warranted. This trial was registered at clinicaltrials.gov as NCT02811835. © 2016 American Society for Nutrition.

Relationships between urinary electrolytes excretion and central hemodynamics, and arterial stiffness in hypertensive patients.

PubMed

Han, Weizhong; Han, Xiao; Sun, Ningling; Chen, Yunchao; Jiang, Shiliang; Li, Min

2017-08-01

High sodium intake plays an important role in the onset and exacerbation of hypertension. However, the relationships between urinary electrolytes excretion and central hemodynamics and between urinary electrolyte excretion and arterial stiffness are still the subject of debate. This study sought to clarify the associations of salt intake with central aortic pressure and arterial stiffness indicators. A total of 431 untreated hypertensive individuals were recruited into the study. Twenty-four-hour urinary samples were collected to measure the excretion of urinary electrolytes. Central hemodynamics parameters and brachial-ankle pulse wave velocity (baPWV) were measured. We evaluated the independent relationship between urinary sodium or potassium excretion and the abovementioned indices. The mean 24-h urinary sodium of all subjects was 166.6±70.0 mmol/24 h. With increases in urinary sodium excretion, central blood pressure and baPWV values markedly increased. Multiple regression analysis showed that urinary sodium was independently associated with increases in central systolic blood pressure, central diastolic blood pressure, the augmentation index, and baPWV. Significant correlations were identified between high dietary sodium and central hemodynamics and between high dietary sodium and arterial elasticity. Prospective interventional studies in hypertensive patients may be required to determine the effect of salt intake on central hemodynamics.

Geographic and socioeconomic variation of sodium and potassium intake in Italy: results from the MINISAL-GIRCSI programme

PubMed Central

Cappuccio, Francesco P; Ji, Chen; Donfrancesco, Chiara; Palmieri, Luigi; Ippolito, Renato; Vanuzzo, Diego; Giampaoli, Simona; Strazzullo, Pasquale

2015-01-01

Objectives To assess geographic and socioeconomic gradients in sodium and potassium intake in Italy. Setting Cross-sectional survey in Italy. Participants 3857 men and women, aged 39–79 years, randomly sampled in 20 regions (as part of a National cardiovascular survey of 8714 men and women). Primary outcome measures Participants’ dietary sodium and potassium intakes were measured by 24 h urinary sodium and potassium excretions. 2 indicators measured socioeconomic status: education and occupation. Bayesian geoadditive models were used to assess spatial and socioeconomic patterns of sodium and potassium intakes accounting for sociodemographic, anthropometric and behavioural confounders. Results There was a significant north-south pattern of sodium excretion in Italy. Participants living in southern Italy (eg, Calabria, Basilicata and Puglia >180 mmol/24 h) had a significantly higher sodium excretion than elsewhere (eg, Val d'Aosta and Trentino-Alto Adige <140 mmol/24 h; p<0.001). There was a linear association between occupation and sodium excretion (p<0.001). When compared with occupation I (top managerial), occupations III and IV had a 6.5% higher sodium excretion (coefficients: 0.054 (90% credible levels 0.014, 0.093) and 0.064 (0.024, 0.104), respectively). A similar relationship was found between educational attainment and sodium excretion (p<0.0001). When compared with those with a university degree, participants with primary and junior school education had a 5.9% higher urinary sodium (coefficients: 0.074 (0.031, 0.116) and 0.038 (0.001, 0.075), respectively). The socioeconomic gradient explained the spatial variation. Potassium excretion was higher in central regions and in some southern regions. Those in occupation V (low-skill workers) showed a 3% lower potassium excretion compared with those in occupation I. However, the socioeconomic gradient only partially explained the spatial variation. Conclusions Salt intake in Italy is significantly higher in less advantaged social groups. This gradient is independent of confounders and explains the geographical variation. PMID:26359282

Geographic and socioeconomic variation of sodium and potassium intake in Italy: results from the MINISAL-GIRCSI programme.

PubMed

Cappuccio, Francesco P; Ji, Chen; Donfrancesco, Chiara; Palmieri, Luigi; Ippolito, Renato; Vanuzzo, Diego; Giampaoli, Simona; Strazzullo, Pasquale

2015-09-10

To assess geographic and socioeconomic gradients in sodium and potassium intake in Italy. Cross-sectional survey in Italy. 3857 men and women, aged 39-79 years, randomly sampled in 20 regions (as part of a National cardiovascular survey of 8714 men and women). Participants' dietary sodium and potassium intakes were measured by 24 h urinary sodium and potassium excretions. 2 indicators measured socioeconomic status: education and occupation. Bayesian geoadditive models were used to assess spatial and socioeconomic patterns of sodium and potassium intakes accounting for sociodemographic, anthropometric and behavioural confounders. There was a significant north-south pattern of sodium excretion in Italy. Participants living in southern Italy (eg, Calabria, Basilicata and Puglia >180 mmol/24 h) had a significantly higher sodium excretion than elsewhere (eg, Val d'Aosta and Trentino-Alto Adige <140 mmol/24 h; p<0.001). There was a linear association between occupation and sodium excretion (p<0.001). When compared with occupation I (top managerial), occupations III and IV had a 6.5% higher sodium excretion (coefficients: 0.054 (90% credible levels 0.014, 0.093) and 0.064 (0.024, 0.104), respectively). A similar relationship was found between educational attainment and sodium excretion (p<0.0001). When compared with those with a university degree, participants with primary and junior school education had a 5.9% higher urinary sodium (coefficients: 0.074 (0.031, 0.116) and 0.038 (0.001, 0.075), respectively). The socioeconomic gradient explained the spatial variation. Potassium excretion was higher in central regions and in some southern regions. Those in occupation V (low-skill workers) showed a 3% lower potassium excretion compared with those in occupation I. However, the socioeconomic gradient only partially explained the spatial variation. Salt intake in Italy is significantly higher in less advantaged social groups. This gradient is independent of confounders and explains the geographical variation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Metabolic alkalosis during immobilization in monkeys (M. nemestrina)

NASA Technical Reports Server (NTRS)

Young, D. R.; Yeh, I.; Swenson, R. S.

1983-01-01

The systemic and renal acid-base response of monkeys during ten weeks of immobilization was studied. By three weeks of immobilization, arterial pH and bicarbonate concentrations were elevated (chronic metabolic alkalosis). Net urinary acid excretion increased in immobilized animals. Urinary bicarbonate excretion decreased during the first three weeks of immobilization, and then returned to control levels. Sustained increases in urinary ammonium excretion were seen throughout the time duration of immobilization. Neither potassium depletion nor hypokalemia was observed. Most parameters returned promptly to the normal range during the first week of recovery. Factors tentatively associated with changes in acid-base status of monkeys include contraction of extracellular fluid volume, retention of bicarbonate, increased acid excretion, and possible participation of extrarenal buffers.

Spot urine sodium excretion as prognostic marker in acutely decompensated heart failure: the spironolactone effect.

PubMed

Ferreira, João Pedro; Girerd, Nicolas; Medeiros, Pedro Bettencourt; Santos, Mário; Carvalho, Henrique Cyrne; Bettencourt, Paulo; Kénizou, David; Butler, Javed; Zannad, Faiez; Rossignol, Patrick

2016-06-01

Loop diuretic resistance characterized by inefficient sodium excretion complicates many patients with acutely decompensated heart failure (ADHF). Mineralocorticoid receptor antagonists (MRAs) in natriuretic doses may improve spot urine sodium excretion and outcomes. Our primary aim was to assess the association of high-dose spironolactone with short-term spot urine sodium excretion, and our secondary aim was to determine if this higher short-term spot urine sodium excretion is associated with reduction in the composite clinical outcome (of cardiovascular mortality and/or ADHF hospitalization) event rate at 180 days. Single-centre, non-randomized, open-label study enrolling 100 patients with ADHF. Patients were treated with standard ADHF therapy alone (n = 50) or oral spironolactone 100 mg/day plus standard ADHF therapy (n = 50). Spot urine samples were collected at day 1 and day 3 of hospitalization. Spironolactone group had significantly higher spot urine sodium levels compared to standard care group at day 3 (84.13 ± 28.71 mmol/L vs 70.74 ± 34.43 mmol/L, p = 0.04). The proportion of patients with spot urinary sodium <60 mmol/L was lower in spironolactone group at day 3 (18.8 vs 45.7, p = 0.01). In multivariate analysis, spironolactone was independently associated with increased spot urinary sodium and urinary sodium/potassium ratio of >2 at day 3 (both, p < 0.05). Higher spot urine sodium levels were associated with a lower event rate [HR for urinary sodium >100 mmol/L = 0.16 (0.06-0.42), p < 0.01, compared to <60], and provided a significant prognostic gain measured by net reclassification indexes. Spot urinary sodium levels >60 mmol/L and urinary sodium/potassium ratio >2 measured at day 3 of hospitalization for ADHF are associated with improved mid-term outcomes. Spironolactone is associated with increased spot urinary sodium and sodium/potassium ratio >2.

Sodium-bicarbonated mineral water decreases aldosterone levels without affecting urinary excretion of bone minerals.

PubMed

Schoppen, Stefanie; Pérez-Granados, Ana M; Carbajal, Angeles; Sarriá, Beatriz; Navas-Carretero, Santiago; Pilar Vaquero, M

2008-06-01

AIM To assess in healthy postmenopausal women the influence of consuming sodium-bicarbonated mineral water on postprandial evolution of serum aldosterone and urinary electrolyte excretion. Eighteen postmenopausal women consumed 500 ml of two sodium-bicarbonated mineral waters (sodium-bicarbonated mineral water 1 and sodium-bicarbonated mineral water 2) and a low-mineral water with a standard meal. Postprandial blood samples were taken at 60, 120, 240, 360 and 420 min and aldosterone concentrations were measured. Postprandial urinary minerals were determined. Urinary and total mineral excretion and urinary mineral concentrations did not differ except for sodium concentration, which was significantly higher with sodium-bicarbonated mineral water 1 than with low-mineral water (P = 0.005). There was a time effect (P = 0.003) on the aldosterone concentration. At 120 min, aldosterone concentrations were lower with sodium-bicarbonated mineral water 1 (P = 0.021) and sodium-bicarbonated mineral water 2 (P = 0.030) compared with low-mineral water. Drinking a sodium-rich bicarbonated mineral water with a meal increases urinary sodium concentration excretion without changes in the excretion of potassium and bone minerals.

Daily potassium intake and sodium-to-potassium ratio in the reduction of blood pressure: a meta-analysis of randomized controlled trials.

PubMed

Binia, Aristea; Jaeger, Jonathan; Hu, Youyou; Singh, Anurag; Zimmermann, Diane

2015-08-01

To evaluate the efficacy of daily potassium intake on decreasing blood pressure in non-medicated normotensive or hypertensive patients, and to determine the relationship between potassium intake, sodium-to-potassium ratio and reduction in blood pressure. Mixed-effect meta-analyses and meta-regression models. Medline and the references of previous meta-analyses. Randomized controlled trials with potassium supplementation, with blood pressure as the primary outcome, in non-medicated patients. Fifteen randomized controlled trials of potassium supplementation in patients without antihypertensive medication were selected for the meta-analyses (917 patients). Potassium supplementation resulted in reduction of SBP by 4.7 mmHg [95% confidence interval (CI) 2.4-7.0] and DBP by 3.5 mmHg (95% CI 1.3-5.7) in all patients. The effect was found to be greater in hypertensive patients, with a reduction of SBP by 6.8 mmHg (95% CI 4.3-9.3) and DBP by 4.6 mmHg (95% CI 1.8-7.5). Meta-regression analysis showed that both increased daily potassium excretion and decreased sodium-to-potassium ratio were associated with blood pressure reduction (P < 0.05). Increased total daily potassium urinary excretion from 60 to 100 mmol/day and decrease of sodium-to-potassium ratio were shown to be necessary to explain the estimated effect. Potassium supplementation is associated with reduction of blood pressure in patients who are not on antihypertensive medication, and the effect is significant in hypertensive patients. The reduction in blood pressure significantly correlates with decreased daily urinary sodium-to-potassium ratio and increased urinary potassium. Patients with elevated blood pressure may benefit from increased potassium intake along with controlled or decreased sodium intake.

Influence of renal insufficiency on the pharmacokinetics of cicletanine and its effects on the urinary excretion of electrolytes and prostanoids.

PubMed Central

Ferry, N; Geoffroy, J; Pozet, N; Cuisinaud, G; Benzoni, D; Zech, P Y; Sassard, J

1988-01-01

1. The kinetics of a single oral dose (300 mg) of cicletanine a new antihypertensive drug with diuretic properties, and its effects on the urinary excretion of electrolytes and of the major stable metabolites of prostacyclin and thromboxane A2 were studied in patients with normal renal function (n = 6), mild (n = 9) and severe (n = 10) renal insufficiency. 2. In normotensive subjects with normal renal function, cicletanine was rapidly and regularly absorbed, its apparent elimination half-life established around 7 h, and both its renal clearance (0.4 ml min-1) and its cumulative renal excretion (0.85% of the administered dose), were low. Mild renal insufficiency did not significantly alter these parameters, while severe renal impairment reduced the renal clearance and the cumulative urinary excretion of cicletanine and increased its apparent elimination half-life (31 h). However the area under the plasma curve was not changed due to reduced plasma concentrations in these patients. 3. Cicletanine induced a rapid and marked (four fold as a mean) increase in the urinary excretion of water, sodium and potassium which lasted for 6 to 10 h, in subjects with normal renal function. Renal insufficiency did not alter the slope of the calculated plasma concentration-effects curves but reduced the maximum effect observed for water, sodium and potassium. 4. A single oral dose of cicletanine did not change the urinary excretion of 6-keto-prostaglandin F1 alpha and thromboxane B2 in the three groups of patients studied, the basal values of which being found to be closely related to the creatinine clearance.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3358898

The Yanomami Indians in the INTERSALT Study.

PubMed

Mancilha-Carvalho, Jairo de Jesus; Souza e Silva, Nelson Albuquerque

2003-03-01

To study the distribution and interrelationship among constitutional and biochemical variables with blood pressure (BP) in an population of Yanomami indians. To compare these findings with those of other populations. The Yanomami indians were part of the INTERSALT, a study comprising 10,079 males and females, aged from 20 to 59 years, belonging to 52 populations in 32 countries in Africa, the Americas, Asia, and Europe. Each of the 52 centers was required to accrue 200 individuals, 25 participants in each age group. The variables analyzed were as follows: age, sex, arterial BP, urinary sodium and potassium excretion (24-hour urine), body mass index, and alcohol ingestion. The findings in the Yanomami population were as follows: a very low urinary sodium excretion (0.9 mmol/24 h); mean systolic and diastolic BP levels of 95.4 mmHg and 61.4 mmHg, respectively; no cases of hypertension or obesity; and they have no knowledge of alcoholic beverages. Their BP levels do not elevate with age. The urinary sodium excretion relates positively and the urinary potassium excretion relates negatively to systolic BP. This correlation was maintained even when controlled for age and body mass index. A positive relation between salt intake and blood pressure was detected in the analysis of a set of diverse populations participating in the INTERSALT Study, including populations such as the Yanomami Indians. The qualitative observation of their lifestyle provided additional information.

Association of urinary citrate excretion, pH, and net gastrointestinal alkali absorption with diet, diuretic use, and blood glucose concentration.

PubMed

Perinpam, Majuran; Ware, Erin B; Smith, Jennifer A; Turner, Stephen T; Kardia, Sharon L R; Lieske, John C

2017-10-01

Urinary citrate (Ucit) protects against urinary stone formation. Acid base status and diet influence Ucit. However, the effect of demographics, diet, and glucose metabolism on Ucit excretion, urinary pH (U-pH) and net gastrointestinal alkali absorption (NAA) are not known. Twenty-four hour urine samples, blood glucose, creatinine, and cystatin C were obtained from non-Hispanic white sibships in Rochester, MN ( n  = 446; 64.5 ± 9 years; 58% female). Diet was assessed by a food frequency questionnaire. The impact of blood glucose, demographics and dietary elements on Ucit excretion, U-pH, and NAA were evaluated in bivariate and multivariable models and interaction models that included age, sex, and weight. NAA significantly associated with Ucit and U-pH In multivariate models Ucit increased with age, weight, eGFR C ys , and blood glucose, but decreased with loop diuretic and thiazide use. U-pH decreased with serum creatinine, blood glucose, and dietary protein but increased with dietary potassium. NAA was higher in males and increased with age, weight, eGFR C ys and dietary potassium. Significant interactions were observed for Ucit excretion with age and blood glucose, weight and eGFR C ys, and sex and thiazide use. Blood glucose had a significant and independent effect on U-pH and also Ucit. This study provides the first evidence that blood glucose could influence urinary stone risk independent of urinary pH, potentially providing new insight into the association of obesity and urinary stone disease. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Calcineurin inhibitors block sodium-chloride cotransporter dephosphorylation in response to high potassium intake.

PubMed

Shoda, Wakana; Nomura, Naohiro; Ando, Fumiaki; Mori, Yutaro; Mori, Takayasu; Sohara, Eisei; Rai, Tatemitsu; Uchida, Shinichi

2017-02-01

Dietary potassium intake is inversely related to blood pressure and mortality. Moreover, the sodium-chloride cotransporter (NCC) plays an important role in blood pressure regulation and urinary potassium excretion in response to potassium intake. Previously, it was shown that NCC is activated by the WNK4-SPAK cascade and dephosphorylated by protein phosphatase. However, the mechanism of NCC regulation with acute potassium intake is still unclear. To identify the molecular mechanism of NCC regulation in response to potassium intake, we used adult C57BL/6 mice fed a 1.7% potassium solution by oral gavage. We confirmed that acute potassium load rapidly dephosphorylated NCC, which was not dependent on the accompanying anions. Mice were treated with tacrolimus (calcineurin inhibitor) and W7 (calmodulin inhibitor) before the oral potassium loads. Dephosphorylation of NCC induced by potassium was significantly inhibited by both tacrolimus and W7 treatment. There was no significant difference in WNK4, OSR1, and SPAK expression after high potassium intake, even after tacrolimus and W7 treatment. Another phosphatase, protein phosphatase 1, and its endogenous inhibitor I-1 did not show a significant change after potassium intake. Hyperkaliuria, induced by high potassium intake, was significantly suppressed by tacrolimus treatment. Thus, calcineurin is activated by an acute potassium load, which rapidly dephosphorylates NCC, leading to increased urinary potassium excretion. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

A Continuum of Renin-Independent Aldosteronism in Normotension

PubMed Central

Baudrand, Rene; Guarda, Francisco J.; Fardella, Carlos; Hundemer, Gregory; Brown, Jenifer; Williams, Gordon; Vaidya, Anand

2017-01-01

Primary aldosteronism (PA) is a severe form of autonomous aldosteronism. Milder forms of autonomous and renin-independent aldosteronism may be common, even in normotension. We characterized aldosterone secretion in 210 normotensives who had suppressed plasma renin activity (PRA<1.0 ng/mL/h), completed an oral sodium suppression test, received an infusion of angiotensin II (AngII), and had measurements of blood pressure (BP) and renal plasma flow (RPF). Continuous associations between urinary aldosterone excretion rate (AER), renin, and potassium handling were investigated. Severe autonomous aldosterone secretion that was consistent with confirmed PA was defined based on accepted criteria of an AER >12 mcg/24h with urinary sodium excretion >200 mmol/24h. Across the population, there were strong and significant associations between higher AER and higher urinary potassium excretion, higher AngII-stimulated aldosterone, and lower PRA, suggesting a continuum of renin-independent aldosteronism and mineralocorticoid receptor activity. Autonomous aldosterone secretion that fulfilled confirmatory criteria for PA was detected in 29 participants (14%). Normotensives with evidence suggestive of confirmed PA had higher 24h urinary AER (20.2±12.2 vs. 6.2±2.9 mcg/24h, P<0.001) as expected, but also higher AngII-stimulated aldosterone (12.4±8.6 vs. 6.6±4.3 ng/dL, P<0.001) and lower 24h urinary sodium-to-potassium excretion (2.69±0.65 vs. 3.69±1.50 mmol/mmol, P=0.001); however, there were no differences in age, aldosterone-to-renin ratio, BP, or RPF between the two groups. These findings indicate a continuum of renin-independent aldosteronism and mineralocorticoid receptor activity in normotension that ranges from subtle to overtly dysregulated and autonomous. Longitudinal studies are needed to determine whether this spectrum of autonomous aldosterone secretion contributes to hypertension and cardiovascular disease. PMID:28289182

Winter fasting and refeeding effects on urine characteristics in white-tailed deer

USGS Publications Warehouse

DelGiudice, G.D.; Mech, L.D.; Seal, U.S.; Karns, P.D.

1987-01-01

The effects of dietary protein, fasting, and refeeding on urinary characteristics of 9 captive, female white-tailed deer (Odocoileus virginianus) were studied from 23 February to 3 May 1984. Urinary sodium (na) and potassium (K) were diminished in fasted deer after 2 and 4 weeks. Renal excretion of Na and K were lower, whereas urinary phosphorus (P) was higher in fasted deer compared to deer fed high protein-high energy (HPHE) diets. Urinary P excretion of the fasted deer was also greater than in a low protein-high energy (LPHE)-fed group. Urinary area excretion of fasted deer was similar to that of deer fed low and high protein diets. One fasted deer died during the study and exhibited notably high excretion of urea, Na, K, and calcium (Ca). No effects of the 2 levels of dietary protein on urinary characteristics were detected. Urinary Na:C and K:C ratios wer significantly correlated with Na and K intake. Urinalysis has potential as a sensitive means of monitoring the nutritional status of white-tailed deer. Data are presented as reference values for interpretation of data from deer under less controlled circumstances.

Relation of Urinary Calcium and Magnesium Excretion to Blood Pressure

PubMed Central

Kesteloot†, Hugo; Tzoulaki, Ioanna; Brown, Ian J.; Chan, Queenie; Wijeyesekera, Anisha; Ueshima, Hirotsugu; Zhao, Liancheng; Dyer, Alan R.; Unwin, Robert J.; Stamler, Jeremiah; Elliott, Paul

2011-01-01

Data indicate an inverse association between dietary calcium and magnesium intakes and blood pressure (BP); however, much less is known about associations between urinary calcium and magnesium excretion and BP in general populations. The authors assessed the relation of BP to 24-hour excretion of calcium and magnesium in 2 cross-sectional studies. The International Study of Macro- and Micro-Nutrients and Blood Pressure (INTERMAP) comprised 4,679 persons aged 40–59 years from 17 population samples in China, Japan, the United Kingdom, and the United States, and the International Cooperative Study on Salt, Other Factors, and Blood Pressure (INTERSALT) comprised 10,067 persons aged 20–59 years from 52 samples around the world. Timed 24-hour urine collections, BP measurements, and nutrient data from four 24-hour dietary recalls (INTERMAP) were collected. In multiple linear regression analyses, urinary calcium excretion was directly associated with BP. After adjustment for multiple confounders (including weight, height, alcohol intake, calcium intake, urinary sodium level, and urinary potassium intake), systolic BP was 1.9 mm Hg higher per each 4.1 mmol per 24 hours (2 standard deviations) of higher urinary calcium excretion (associations were smaller for diastolic BP) in INTERMAP. Qualitatively similar associations were observed in INTERSALT analyses. Associations between magnesium excretion and BP were small and nonsignificant for most of the models examined. The present data suggest that altered calcium homoeostasis, as exhibited by increased calcium excretion, is associated with higher BP levels. PMID:21624957

Potassium bicarbonate attenuates the urinary nitrogen excretion that accompanies an increase in dietary protein and may promote calcium absorption

USDA-ARS?s Scientific Manuscript database

Protein is an essential component of muscle and bone. However, the acidic byproducts of protein metabolism may have a negative impact on the musculoskeletal system particularly in older individuals with declining renal function. We sought to determine whether adding an alkaline salt, potassium bicar...

Constitutively Active SPAK Causes Hyperkalemia by Activating NCC and Remodeling Distal Tubules.

PubMed

Grimm, P Richard; Coleman, Richard; Delpire, Eric; Welling, Paul A

2017-09-01

Aberrant activation of with no lysine (WNK) kinases causes familial hyperkalemic hypertension (FHHt). Thiazide diuretics treat the disease, fostering the view that hyperactivation of the thiazide-sensitive sodium-chloride cotransporter (NCC) in the distal convoluted tubule (DCT) is solely responsible. However, aberrant signaling in the aldosterone-sensitive distal nephron (ASDN) and inhibition of the potassium-excretory renal outer medullary potassium (ROMK) channel have also been implicated. To test these ideas, we introduced kinase-activating mutations after Lox-P sites in the mouse Stk39 gene, which encodes the terminal kinase in the WNK signaling pathway, Ste20-related proline-alanine-rich kinase (SPAK). Renal expression of the constitutively active (CA)-SPAK mutant was specifically targeted to the early DCT using a DCT-driven Cre recombinase. CA-SPAK mice displayed thiazide-treatable hypertension and hyperkalemia, concurrent with NCC hyperphosphorylation. However, thiazide-mediated inhibition of NCC and consequent restoration of sodium excretion did not immediately restore urinary potassium excretion in CA-SPAK mice. Notably, CA-SPAK mice exhibited ASDN remodeling, involving a reduction in connecting tubule mass and attenuation of epithelial sodium channel (ENaC) and ROMK expression and apical localization. Blocking hyperactive NCC in the DCT gradually restored ASDN structure and ENaC and ROMK expression, concurrent with the restoration of urinary potassium excretion. These findings verify that NCC hyperactivity underlies FHHt but also reveal that NCC-dependent changes in the driving force for potassium secretion are not sufficient to explain hyperkalemia. Instead, a DCT-ASDN coupling process controls potassium balance in health and becomes aberrantly activated in FHHt. Copyright © 2017 by the American Society of Nephrology.

Conservation of body calcium by increased dietary intake of potassium: A potential measure to reduce the osteoporosis process during prolonged exposure to microgravity

NASA Technical Reports Server (NTRS)

Nechay, Bohdan R.

1989-01-01

During the 1988 NASA Summer Faculty Fellowship Program, it was proposed that the loss of skeletal calcium upon prolonged exposure to microgravity could be explained, in part, by a renal maladjustment characterized by an increased urinary excretion of calcium. It was theorized that because the conservation of body fluids and electrolytes depends upon the energy of adenosine triphosphate and enzymes that control the use of its energy for renal ion transport, an induction of renal sodium and potassium-dependent adenosine triphosphatase (Na + K ATPase) by oral loading with potassium would increase the reabsorption of sodium directly and that of calcium indirectly, leading to improved hydration and to reduced calcium loss. Preliminary studies showed the following. Rats drinking water containing 0.2 M potassium chloride for six to 13 days excreted in urine 22 muEq of calcium and 135 muEq of sodium per 100 grams of body weight per day. The corresponding values for control rats drinking tap water were 43 muEq and 269 muEq respectively. Renal Na + K ATPase activity in potassium loaded rats was higher than in controls. Thus, oral potassium loading resulted in increased Na + K ATPase activity and diminished urinary excretion of calcium and of sodium as predicted by the hypothesis. An extension of these studies to humans has the potential of resulting in development of harmless, non-invasive, drug-free, convenient measures to reduce bone loss and other electrolyte and fluid problems in space travelers exposed to prolonged periods of microgravity.

Calcium and nitrogen balance, experiment M007

NASA Technical Reports Server (NTRS)

Whedon, G. D.; Lutwak, L.; Neuman, W. F.; Lachance, P. A.

1971-01-01

The collection of data on the response of the skeletal and muscular systems to 14-day space flights was evaluated for loss of calcium, nitrogen, and other metabolically related elements. Considerable interindividual variability was demonstrated in all experimental factors that were measured. Calcium balance became less positive and urinary phosphate excretion increased substantially in flight despite a reduction in phosphate intake. Patterns of excretion of magnesium, sodium, potassium, and chloride were different for each subject, and, in part, could be correlated with changes in adrenocortical steroid production. The principal hormonal change was a striking decrease during flight in the urinary excretion of 17-hydroxycortocosteroids. Dermal losses of calcium, magnesium, sulfate, and phosphate were insignificant during all three phases.

Hypokalemic Paralysis Complicated by Concurrent Hyperthyroidism and Chronic Alcoholism: A Case Report.

PubMed

Tsai, Ming-Hsien; Lin, Shih-Hua; Leu, Jyh-Gang; Fang, Yu-Wei

2015-09-01

Thyrotoxic periodic paralysis (TPP) is characterized by the presence of muscle paralysis, hypokalemia, and hyperthyroidism. We report the case of a young man with paralysis of the lower extremities, severe hypokalemia, and concurrent hyperthyroidism. TPP was suspected; therefore, treatment consisting of judicious potassium (K+) repletion and β-blocker administration was initiated. However, urinary K+ excretion rate, as well as refractoriness to treatment, was inconsistent with TPP. Chronic alcoholism was considered as an alternative cause of hypokalemia, and serum K+ was restored through vigorous K repletion and the addition of K+ -sparing diuretics. The presence of thyrotoxicosis and hypokalemia does not always indicate a diagnosis of TPP. Exclusion of TPP can be accomplished by immediate evaluation of urinary K+ excretion, acid-base status, and the amount of potassium chloride required to correct hypokalemia at presentation.

Hypokalemic Paralysis Complicated by Concurrent Hyperthyroidism and Chronic Alcoholism

PubMed Central

Tsai, Ming-Hsien; Lin, Shih-Hua; Leu, Jyh-Gang; Fang, Yu-Wei

2015-01-01

Abstract Thyrotoxic periodic paralysis (TPP) is characterized by the presence of muscle paralysis, hypokalemia, and hyperthyroidism. We report the case of a young man with paralysis of the lower extremities, severe hypokalemia, and concurrent hyperthyroidism. TPP was suspected; therefore, treatment consisting of judicious potassium (K+) repletion and β-blocker administration was initiated. However, urinary K+ excretion rate, as well as refractoriness to treatment, was inconsistent with TPP. Chronic alcoholism was considered as an alternative cause of hypokalemia, and serum K+ was restored through vigorous K+ repletion and the addition of K+-sparing diuretics. The presence of thyrotoxicosis and hypokalemia does not always indicate a diagnosis of TPP. Exclusion of TPP can be accomplished by immediate evaluation of urinary K+ excretion, acid-base status, and the amount of potassium chloride required to correct hypokalemia at presentation. PMID:26426670

Urinary Netrin-1: A New Biomarker for the Early Diagnosis of Renal Damage in Obese Children.

PubMed

Övünç Hacıhamdioğlu, Duygu; Hacıhamdioğlu, Bülent; Altun, Demet; Müftüoğlu, Tuba; Karademir, Ferhan; Süleymanoğlu, Selami

2016-09-01

Urinary netrin-1 is a new marker to demonstrate early tubular damage. The aim of this study was to determine whether urinary netrin-1 is increased in obese children. A total of 68 normoalbuminuric and normotensive obese patients and 65 controls were included in the study. Urine samples were collected for assessment of urinary phosphorus, sodium, potassium, creatinine, albumin, and netrin-1. Blood samples were collected for measurements of fasting glucose, insulin, lipid, phosphorus, sodium, potassium, and creatinine levels. Homeostatic model assessment insulin resistance index was calculated. Gender and age were similar between obese and control groups (12.01±3.03 vs. 11.7±3.2 years, p=0.568 and 33 vs. 35 girls, p=0.543, respectively). Obese patients had significantly higher netrin-1 excretion than the controls (841.68±673.17 vs. 228.94±137.25 pg/mg creatinine, p=0.000). Urinary netrin-1 level was significantly higher in obese subjects with insulin resistance compared to those without insulin resistance (1142±1181 vs. 604.9±589.91 pg/mg creatinine, p=0.001). In normotensive and normoalbuminuric obese children, urinary netrin-1 level can increase before onset of albuminuria. Urinary netrin-1 excretion appears to be affected predominantly by insulin resistance and hyperinsulinemia. Urinary netrin-1 may be a new biomarker for determining early tubular injury in obese children.

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

PubMed

Feng, Weijing; Cai, Qingqing; Yuan, Woliang; Liu, Yu; Bardeesi, Adham Sameer A; Wang, Jingfeng; Chen, Jie; Huang, Hui

2016-02-01

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.

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

PubMed Central

Feng, Weijing; Cai, Qingqing; Yuan, Woliang; Liu, Yu; Bardeesi, Adham Sameer A.; Wang, Jingfeng; Chen, Jie; Huang, Hui

2016-01-01

Abstract 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. PMID:26871780

Relationship Between Urinary Nitrate Excretion and Blood Pressure in the InChianti Cohort.

PubMed

Smallwood, Miranda J; Ble, Alessandro; Melzer, David; Winyard, Paul G; Benjamin, Nigel; Shore, Angela C; Gilchrist, Mark

2017-07-01

Inorganic nitrate from the oxidation of endogenously synthesized nitric oxide (NO) or consumed in the diet can be reduced to NO via a complex enterosalivary circulation pathway. The relationship between total nitrate exposure by measured urinary nitrate excretion and blood pressure in a large population sample has not been assessed previously. For this cross-sectional study, 24-hour urinary nitrate excretion was measured by spectrophotometry in the 919 participants from the InChianti cohort at baseline and blood pressure measured with a mercury sphygmomanometer. After adjusting for age and sex only, diastolic blood pressure was 1.9 mm Hg lower in subjects with ≥2 mmol urinary nitrate excretion compared with those excreting <1 mmol nitrate in 24 hours: systolic blood pressure was 3.4 mm Hg (95% confidence interval (CI): -3.5 to -0.4) lower in subjects for the same comparison. Effect sizes in fully adjusted models (for age, sex, potassium intake, use of antihypertensive medications, diabetes, HS-CRP, or current smoking status) were marginally larger: systolic blood pressure in the ≥2 mmol urinary nitrate excretion group was 3.9 (CI: -7.1 to -0.7) mm Hg lower than in the comparison <1 mmol excretion group. Modest differences in total nitrate exposure are associated with lower blood pressure. These differences are at least equivalent to those seen from substantial (100 mmol) reductions in sodium intake. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Relation of Dietary Sodium (Salt) to Blood Pressure and Its Possible Modulation by Other Dietary Factors: The INTERMAP Study.

PubMed

Stamler, Jeremiah; Chan, Queenie; Daviglus, Martha L; Dyer, Alan R; Van Horn, Linda; Garside, Daniel B; Miura, Katsuyuki; Wu, Yangfeng; Ueshima, Hirotsugu; Zhao, Liancheng; Elliott, Paul

2018-04-01

Available data indicate that dietary sodium (as salt) relates directly to blood pressure (BP). Most of these findings are from studies lacking dietary data; hence, it is unclear whether this sodium-BP relationship is modulated by other dietary factors. With control for multiple nondietary factors, but not body mass index, there were direct relations to BP of 24-hour urinary sodium excretion and the urinary sodium/potassium ratio among 4680 men and women 40 to 59 years of age (17 population samples in China, Japan, United Kingdom, and United States) in the INTERMAP (International Study on Macro/Micronutrients and Blood Pressure), and among its 2195 American participants, for example, 2 SD higher 24-hour urinary sodium excretion (118.7 mmol) associated with systolic BP 3.7 mm Hg higher. These sodium-BP relations persisted with control for 13 macronutrients, 12 vitamins, 7 minerals, and 18 amino acids, for both sex, older and younger, blacks, Hispanics, whites, and socioeconomic strata. With control for body mass index, sodium-BP-but not sodium/potassium-BP-relations were attenuated. Normal weight and obese participants manifested significant positive relations to BP of urinary sodium; relations were weaker for overweight people. At lower but not higher levels of 24-hour sodium excretion, potassium intake blunted the sodium-BP relation. The adverse association of dietary sodium with BP is minimally attenuated by other dietary constituents; these findings underscore the importance of reducing salt intake for the prevention and control of prehypertension and hypertension. URL: https://www.clinicaltrials.gov. Unique identifier: NCT00005271. © 2018 American Heart Association, Inc.

Relationship of nutrition knowledge and self-reported dietary behaviors with urinary excretion of sodium and potassium: comparison between dietitians and nondietitians.

PubMed

Sugimoto, Minami; Asakura, Keiko; Masayasu, Shizuko; Sasaki, Satoshi

2016-05-01

The effectiveness of better nutrition knowledge and dietary behavior on healthier dietary intake is still controversial. We hypothesized that nutritional knowledge and dietary behavior are associated with sodium and potassium intake in adult women. A cross-sectional study was conducted at welfare facilities located in 20 areas of Japan. Ninety-nine female dietitians and 117 nondietitians aged 20 to 69 years participated. Sodium and potassium intake were assessed with two 24-hour urine collections and 4-day semiweighed diet records. Nutritional knowledge and dietary behavior were accessed with 3 questionnaires. Analysis of covariance was performed to compare sodium and potassium excretion and selected nutrition and food intake between dietitians and nondietitians. After adjustment for age and smoking habit, sodium and potassium excretion did not significantly differ between the 2 groups (3857 vs 3959 mg/d, P = .57, and 2016 vs 1886 mg/d, P = .10, respectively). Sodium/potassium ratio was significantly lower in the dietitians (P = .044). The dietitians used food labels for sodium contents more often than the nondietitians and consumed more fruits and vegetables (P = .048 and P < .0001, respectively) and less sugar and confectionaries and fat and oils (P = .016 and P = .010, respectively). In conclusion, the higher level of nutritional knowledge and better dietary behavior were not associated with either sodium or potassium excretion but were moderately associated with sodium/potassium ratio. Copyright © 2016 Elsevier Inc. All rights reserved.

Circadian rhythmicity of the urinary excretion of mercury, potassium and catecholamines in unconventional shift-work systems.

PubMed

Vokac, Z; Gundersen, N; Magnus, P; Jebens, E; Bakka, T

1980-09-01

The round the clock urinary excretion rates of mercury were assessed for two series of unconventional patterns of activity and sleep in subjects who were not exposed to occupational, medical, or other obvious sources of mercury. In the first series the urine was collected in 3-h periods from six subjects during the first and last 2 d of a four-week, continuous 6-h shift (car ferry, watches either 0800--1400 and 2000--0200 or 1400--2000 and 0200--0800). In the second series the urine was collected in 4-h periods from five subjects working an 8-h experimental rotation shift compressed into 5 d (work two mornings--8-h interval--work two nights--8-h interval--work two afternoons). The mean daily excretion rate of the 11 subjects (48 investigation days, 334 urine samples) was 14.5 pmol of mercury/min (range 5.5--24.4 pmol of mercury/min). The mercury excretion oscillated regularly during 24 h by +/- 20--25% of the individual's daily mean excretion rates. The peak excretion rates were found at 0652 in the first and 0642 in the second series (cosinor treatment). Due to the circadian rhythm the mean 24-h excretion rates were best represented (correlation coefficient 0.92) by analyses of urine produced around noon (spot samples, collection periods 1100--1400 and 1000-1400, respectively). The circadian oscillations of mercury excretion were not influenced by the widely different and varying activity-sleep patterns of the two series. The rhythmicity of potassium excretion (peaks at around 1400) was more irregular. The stable oscillations of mercury excretion contrasted most with the excretion of adrenaline and noradrenaline, which, without losing the basic 24-h rhythmicity, closely followed the unconventional patterns of activity and sleep.

Validation and Assessment of Three Methods to Estimate 24-h Urinary Sodium Excretion from Spot Urine Samples in High-Risk Elder Patients of Stroke from the Rural Areas of Shaanxi Province

PubMed Central

Ma, Wenxia; Yin, Xuejun; Zhang, Ruijuan; Liu, Furong; Yang, Danrong; Fan, Yameng; Rong, Jie; Tian, Maoyi; Yu, Yan

2017-01-01

Background: 24-h urine collection is regarded as the “gold standard” for monitoring sodium intake at the population level, but ensuring high quality urine samples is difficult to achieve. The Kawasaki, International Study of Sodium, Potassium, and Blood Pressure (INTERSALT) and Tanaka methods have been used to estimate 24-h urinary sodium excretion from spot urine samples in some countries, but few studies have been performed to compare and validate these methods in the Chinese population. Objective: To compare and validate the Kawasaki, INTERSALT and Tanaka formulas in predicting 24-h urinary sodium excretion using spot urine samples in 365 high-risk elder patients of strokefrom the rural areas of Shaanxi province. Methods: Data were collected from a sub-sample of theSalt Substitute and Stroke Study. 365 high-risk elder patients of stroke from the rural areas of Shaanxi province participated and their spot and 24-h urine specimens were collected. The concentrations of sodium, potassium and creatinine in spot and 24-h urine samples wereanalysed. Estimated 24-h sodium excretion was predicted from spot urine concentration using the Kawasaki, INTERSALT, and Tanaka formulas. Pearson correlation coefficients and agreement by Bland-Altman method were computed for estimated and measured 24-h urinary sodium excretion. Results: The average 24-h urinary sodium excretion was 162.0 mmol/day, which representing a salt intake of 9.5 g/day. Three predictive equations had low correlation with the measured 24-h sodium excretion (r = 0.38, p < 0.01; ICC = 0.38, p < 0.01 for the Kawasaki; r = 0.35, p < 0.01; ICC = 0.31, p < 0.01 for the INTERSALT; r = 0.37, p < 0.01; ICC = 0.34, p < 0.01 for the Tanaka). Significant biases between estimated and measured 24-h sodium excretion were observed (all p < 0.01 for three methods). Among the three methods, the Kawasaki method was the least biased compared with the other two methods (mean bias: 31.90, 95% Cl: 23.84, 39.97). Overestimation occurred when the Kawasaki and Tanaka methods were used while the INTERSALT method underestimated 24-h sodium excretion. Conclusion: The Kawasaki, INTERSALT and Tanaka methods for estimation of 24-h urinary sodium excretion from spot urine specimens were inadequate for the assessment of sodium intake at the population level in high-risk elder patients of stroke from the rural areas of Shaanxi province, although the Kawasaki method was the least biased compared with the other two methods. PMID:29019912

Validation and Assessment of Three Methods to Estimate 24-h Urinary Sodium Excretion from Spot Urine Samples in High-Risk Elder Patients of Stroke from the Rural Areas of Shaanxi Province.

PubMed

Ma, Wenxia; Yin, Xuejun; Zhang, Ruijuan; Liu, Furong; Yang, Danrong; Fan, Yameng; Rong, Jie; Tian, Maoyi; Yu, Yan

2017-10-11

Background : 24-h urine collection is regarded as the "gold standard" for monitoring sodium intake at the population level, but ensuring high quality urine samples is difficult to achieve. The Kawasaki, International Study of Sodium, Potassium, and Blood Pressure (INTERSALT) and Tanaka methods have been used to estimate 24-h urinary sodium excretion from spot urine samples in some countries, but few studies have been performed to compare and validate these methods in the Chinese population. Objective : To compare and validate the Kawasaki, INTERSALT and Tanaka formulas in predicting 24-h urinary sodium excretion using spot urine samples in 365 high-risk elder patients of strokefrom the rural areas of Shaanxi province. Methods : Data were collected from a sub-sample of theSalt Substitute and Stroke Study. 365 high-risk elder patients of stroke from the rural areas of Shaanxi province participated and their spot and 24-h urine specimens were collected. The concentrations of sodium, potassium and creatinine in spot and 24-h urine samples wereanalysed. Estimated 24-h sodium excretion was predicted from spot urine concentration using the Kawasaki, INTERSALT, and Tanaka formulas. Pearson correlation coefficients and agreement by Bland-Altman method were computed for estimated and measured 24-h urinary sodium excretion. Results : The average 24-h urinary sodium excretion was 162.0 mmol/day, which representing a salt intake of 9.5 g/day. Three predictive equations had low correlation with the measured 24-h sodium excretion (r = 0.38, p < 0.01; ICC = 0.38, p < 0.01 for the Kawasaki; r = 0.35, p < 0.01; ICC = 0.31, p < 0.01 for the INTERSALT; r = 0.37, p < 0.01; ICC = 0.34, p < 0.01 for the Tanaka). Significant biases between estimated and measured 24-h sodium excretion were observed (all p < 0.01 for three methods). Among the three methods, the Kawasaki method was the least biased compared with the other two methods (mean bias: 31.90, 95% Cl: 23.84, 39.97). Overestimation occurred when the Kawasaki and Tanaka methods were used while the INTERSALT method underestimated 24-h sodium excretion. Conclusion : The Kawasaki, INTERSALT and Tanaka methods for estimation of 24-h urinary sodium excretion from spot urine specimens were inadequate for the assessment of sodium intake at the population level in high-risk elder patients of stroke from the rural areas of Shaanxi province, although the Kawasaki method was the least biased compared with the other two methods.

[Resorption of hydrocyanic acid from linseed].

PubMed

Schulz, V; Löffler, A; Gheorghiu, T

1983-01-01

Resorption of hydrocyanic acid after ingestion of linseed was investigated in 20 healthy volunteers and 5 patients. The persons investigated took a single dose of 30 g or of 100 g of linseed or they received throughout several weeks 15 g. t.i.d. One volunteer also took for purposes of comparison bitter almonds or potassium cyanide. Before, during and after the periods of ingestion plasma levels of hydrocyanic acid and of thiocyanate were normal. During long-term trials urinary excretion of thiocyanate was monitored regularly. Intake of linseed even in extremely high dosages never caused significant rises of plasma thiocyanate levels; this, however, was the case after intake of bitter almonds or potassium cyanide. Thus, it can be excluded, that intoxication by hydrocyanic acid can be caused by linseed. Long-term intake of linseed however, raised plasma levels of thiocyanate significantly; at the same time urinary excretion of thiocyanate increased.

Fish Oil Supplementation and Urinary Oxalate Excretion in Normal Subjects on a Low-oxalate Diet

PubMed Central

Lange, Jessica N.; Mufarrij, Patrick W.; Easter, Linda; Knight, John; Holmes, Ross P.; Assimos, Dean G.

2014-01-01

OBJECTIVE To determine if fish oil supplementation reduces endogenous oxalate synthesis in healthy subjects. MATERIALS AND METHODS Fifteen healthy non–stone-forming adults participated in this study. Subjects first abstained from using vitamins, medications, or foods enriched in omega-3 fatty acids for 30 days. Next, they collected two 24-hour urine specimens while consuming a self-selected diet. Subjects consumed an extremely low-oxalate and normal-calcium diet for 5 days and collected 24-hour urine specimens on the last 3 days of this diet. Next, the subjects took 2 fish oil capsules containing 650-mg eicosapentaenoic acid and 450-mg docosahexaenoic acid twice daily for 30 days. They consumed a self-selected diet on days 1–25 and the controlled diet on days 26–30. Twenty-four-hour urine samples were collected on days 28–30. Excretion levels of urinary analytes including oxalate and glycolate were analyzed. RESULTS Although there was a significant reduction in urinary oxalate, magnesium, and potassium excretions and an increase in uric acid excretion during the controlled dietary phases compared with the self-selected diet, there were no significant differences in their excretion during controlled diet phases with and without fish oil supplementation. CONCLUSION These results suggest that fish oil supplementation does not reduce endogenous oxalate synthesis or urinary oxalate excretion in normal adults during periods of extremely low oxalate intake. However, these results do not challenge the previously described reduction in urinary oxalate excretion demonstrated in normal subjects consuming a moderate amount of oxalate in conjunction with fish oil. PMID:25102784

Estimation of Daily Sodium and Potassium Excretion Using Spot Urine and 24-Hour Urine Samples in a Black Population (Benin).

PubMed

Mizéhoun-Adissoda, Carmelle; Houehanou, Corine; Chianéa, Thierry; Dalmay, François; Bigot, André; Preux, Pierre-Marie; Bovet, Pascal; Houinato, Dismand; Desport, Jean-Claude

2016-07-01

The 24-hour urine collection method is considered the gold standard for the estimation of ingested potassium and sodium. Because of the impracticalities of collecting all urine over a 24-hour period, spot urine is often used for epidemiological investigations. This study aims to assess the agreement between spot urine and 24-hour urine measurements to determine sodium and potassium intake. A total of 402 participants aged 25 to 64 years were randomly selected in South Benin. Spot urine was taken during the second urination of the day. Twenty-four-hour urine was also collected. Samples (2-mL) were taken and then stored at -20°C. The analysis was carried out using potentiometric dosage. The agreement between spot urine and 24-hour urine measurements was established using Bland-Altman plots. A total of 354 results were analyzed. Daily sodium chloride and potassium chloride urinary excretion means were 10.2±4.9 g/24 h and 2.9±1.4 g/24 h, respectively. Estimated daily sodium chloride and potassium chloride means from the spot urine were 10.7±7.0 g/24 h and 3.9±2.1 g/24 h, respectively. Concordance coefficients were 0.61 at d=-0.5 g, (d±2SD=-11 g and 10.1 g) for sodium chloride and 0.61 at d=-1 g, (d±2SD=-3.8 g and 1.8 g) for potassium chloride. Spot urine method is acceptable for estimating 24-hour urinary sodium and potassium excretion to assess sodium and potassium intake in a black population. However, the confidence interval for the mean difference, which is too large, makes the sodium chloride results inadmissible at a clinical level. © 2015 Wiley Periodicals, Inc.

Circadian rhythm of urinary potassium excretion during treatment with an angiotensin receptor blocker.

PubMed

Ogiyama, Yoshiaki; Miura, Toshiyuki; Watanabe, Shuichi; Fuwa, Daisuke; Tomonari, Tatsuya; Ota, Keisuke; Kato, Yoko; Ichikawa, Tadashi; Shirasawa, Yuichi; Ito, Akinori; Yoshida, Atsuhiro; Fukuda, Michio; Kimura, Genjiro

2014-12-01

We have reported that the circadian rhythm of urinary potassium excretion (U(K)V) is determined by the rhythm of urinary sodium excretion (U(Na)V) in patients with chronic kidney disease (CKD). We also reported that treatment with an angiotensin receptor blocker (ARB) increased the U(Na)V during the daytime, and restored the non-dipper blood pressure (BP) rhythm into a dipper pattern. However, the circadian rhythm of U(K)V during ARB treatment has not been reported. Circadian rhythms of U(Na)V and U(K)V were examined in 44 patients with CKD undergoing treatment with ARB. Whole-day U(Na)V was not altered by ARB whereas whole-day U(K)V decreased. Even during the ARB treatment, the significant relationship persisted between the night/day ratios of U(Na)V and U(K)V (r=0.56, p<0.0001). Whole-day U(K)V/U(Na)V ratio (p=0.0007) and trans-tubular potassium concentration gradient (p=0.002) were attenuated but their night/day ratios remained unchanged. The change in the night/day U(K)V ratio correlated directly with the change in night/day U(Na)V ratio (F=20.4) rather than with the changes in aldosterone, BP or creatinine clearance. The circadian rhythm of U(K)V was determined by the rhythm of UNaV even during ARB treatment. Changes in the circadian U(K)V rhythm were not determined by aldosterone but by U(Na)V. © The Author(s) 2013.

Unexpected effect of furosemide on radioiodine urinary excretion in patients with differentiated thyroid carcinomas treated with iodine 131.

PubMed

Matovic, Milovan D; Jankovic, Slobodan M; Jeremic, Marija; Tasic, Zoran; Vlajkovic, Marina

2009-08-01

In patients receiving (131)I for therapeutic purposes, diuretics are frequently used in an attempt to accelerate elimination of unbound radioiodine, reduce its adverse effects, and shorten the hospital stay. The aims of our study were to investigate the influence of furosemide therapy on urinary excretion of (131)I in patients with differentiated thyroid cancer (DTC), referred to radioiodine ablation after thyroidectomy, and to investigate whether diuretics are useful in daily practice in patients with DTC. Forty-three patients with DTC who had normal renal function and low (131)I uptake in cervical region (3.55 +/- 3.45%) were included in this study. The furosemide (20 mg) and potassium chloride (250 mg) were given orally to 23 patients 3 hours after the (131)I administration, and then q8h for 3 days. Twenty patients did not receive either furosemide or potassium chloride. After (131)I administration, the patients collected their urine for 3 days, and radioactivity of urine sample from each micturition was expressed as percentage of the administered dose. Radioactivity of blood samples was measured after 72 hours, and the values were corrected for decay of (131)I and expressed in relation to the administered dose. Initial whole-body measurement (immediately after (131)I administration) and the whole-body measurement after 72 hours were recorded for all patients. The 72-hour whole-body measurement was corrected for decay of (131)I, and expressed as a percentage of the initial whole-body measurement. Urinary excretion of (131)I was significantly lower in the patients who were taking furosemide and potassium chloride compared with the control group. The whole-body measurements after 72 hours (13.22 +/- 6.55% vs. 8.24 +/- 3.39% of the initial; p < 0.01, respectively) and the blood radioactivity (34.66 +/- 24.84 vs. 11.64 +/- 8.32 cpm/mL per 1 MBq of administered (131)I, p < 0.01) were found to be unexpectedly higher in the patients who were taking furosemide and potassium chloride compared with the control group. Our results demonstrated that furosemide given as an adjuvant medication in patients with DTC causes a significant decrease in urinary excretion of radioiodine and its higher blood concentration. Therefore, furosemide should not be recommended as an adjuvant therapy to radioiodine ablation in patients with DTC previously iodine depleted by low-iodine diet.

Dietary intake and sources of sodium and potassium among Australian schoolchildren: results from the cross-sectional Salt and Other Nutrients in Children (SONIC) study.

PubMed

Grimes, Carley A; Riddell, Lynn J; Campbell, Karen J; Beckford, Kelsey; Baxter, Janet R; He, Feng J; Nowson, Caryl A

2017-10-30

To examine sodium and potassium urinary excretion by socioeconomic status (SES), discretionary salt use habits and dietary sources of sodium and potassium in a sample of Australian schoolchildren. Cross-sectional study. Primary schools located in Victoria, Australia. 666 of 780 children aged 4-12 years who participated in the Salt and Other Nutrients in Children study returned a complete 24-hour urine collection. 24-hour urine collection for the measurement of sodium and potassium excretion and 24-hour dietary recall for the assessment of food sources. Parent and child reported use of discretionary salt. SES defined by parental highest level of education. Participants were 9.3 years (95% CI 9.0 to 9.6) of age and 55% were boys. Mean urinary sodium and potassium excretion was 103 (95% CI 99 to 108) mmol/day (salt equivalent 6.1 g/day) and 47 (95% CI 45 to 49) mmol/day, respectively. Mean molar Na:K ratio was 2.4 (95% CI 2.3 to 2.5). 72% of children exceeded the age-specific upper level for sodium intake. After adjustment for age, sex and day of urine collection, children from a low socioeconomic background excreted 10.0 (95% CI 17.8 to 2.1) mmol/day more sodium than those of high socioeconomic background (p=0.04). The major sources of sodium were bread (14.8%), mixed cereal-based dishes (9.9%) and processed meat (8.5%). The major sources of potassium were dairy milk (11.5%), potatoes (7.1%) and fruit/vegetable juice (5.4%). Core foods provided 55.3% of dietary sodium and 75.5% of potassium while discretionary foods provided 44.7% and 24.5%, respectively. For most children, sodium intake exceeds dietary recommendations and there is some indication that children of lower socioeconomic background have the highest intakes. Children are consuming about two times more sodium than potassium. To improve sodium and potassium intakes in schoolchildren, product reformulation of lower salt core foods combined with strategies that seek to reduce the consumption of discretionary foods are required. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Dietary intake and sources of sodium and potassium among Australian schoolchildren: results from the cross-sectional Salt and Other Nutrients in Children (SONIC) study

PubMed Central

Grimes, Carley A; Riddell, Lynn J; Campbell, Karen J; Beckford, Kelsey; Baxter, Janet R; He, Feng J; Nowson, Caryl A

2017-01-01

Objectives To examine sodium and potassium urinary excretion by socioeconomic status (SES), discretionary salt use habits and dietary sources of sodium and potassium in a sample of Australian schoolchildren. Design Cross-sectional study. Setting Primary schools located in Victoria, Australia. Participants 666 of 780 children aged 4–12 years who participated in the Salt and Other Nutrients in Children study returned a complete 24-hour urine collection. Primary and secondary outcome measures 24-hour urine collection for the measurement of sodium and potassium excretion and 24-hour dietary recall for the assessment of food sources. Parent and child reported use of discretionary salt. SES defined by parental highest level of education. Results Participants were 9.3 years (95% CI 9.0 to 9.6) of age and 55% were boys. Mean urinary sodium and potassium excretion was 103 (95% CI 99 to 108) mmol/day (salt equivalent 6.1 g/day) and 47 (95% CI 45 to 49) mmol/day, respectively. Mean molar Na:K ratio was 2.4 (95% CI 2.3 to 2.5). 72% of children exceeded the age-specific upper level for sodium intake. After adjustment for age, sex and day of urine collection, children from a low socioeconomic background excreted 10.0 (95% CI 17.8 to 2.1) mmol/day more sodium than those of high socioeconomic background (p=0.04). The major sources of sodium were bread (14.8%), mixed cereal-based dishes (9.9%) and processed meat (8.5%). The major sources of potassium were dairy milk (11.5%), potatoes (7.1%) and fruit/vegetable juice (5.4%). Core foods provided 55.3% of dietary sodium and 75.5% of potassium while discretionary foods provided 44.7% and 24.5%, respectively. Conclusions For most children, sodium intake exceeds dietary recommendations and there is some indication that children of lower socioeconomic background have the highest intakes. Children are consuming about two times more sodium than potassium. To improve sodium and potassium intakes in schoolchildren, product reformulation of lower salt core foods combined with strategies that seek to reduce the consumption of discretionary foods are required. PMID:29084791

Characterization of resistant hypertension: association between resistant hypertension, aldosterone, and persistent intravascular volume expansion.

PubMed

Gaddam, Krishna K; Nishizaka, Mari K; Pratt-Ubunama, Monique N; Pimenta, Eduardo; Aban, Inmaculada; Oparil, Suzanne; Calhoun, David A

2008-06-09

Resistant hypertension is a common clinical problem and greatly increases the risk of target organ damage. We evaluated the characteristics of 279 consecutive patients with resistant hypertension (uncontrolled despite the use of 3 antihypertensive agents) and 53 control subjects (with normotension or hypertension controlled by using

Control mechanisms of circadian rhythms in body composition: Implications for manned spaceflight

NASA Technical Reports Server (NTRS)

Ede, M. C. M.

1975-01-01

The mechanisms that underlie the circadian variations in electrolyte content in body fluid compartments were investigated, and the mechanisms that control the oscillations were studied in order to investigate what effects internal desynchronization in such a system would have during manned space flight. The studies were performed using volunteer human subjects and squirrel monkeys. The intercompartmental distribution of potassium was examined when dietary intake, activity, and posture are held constant throughout each 24-hour day. A net flux of potassium was observed out of the body cell mass during the day and a reverse flux from the extracellular fluid into the body cell mass during the night, counterbalanced by changes in urinary potassium excretion. Experiments with monkeys provided evidence for the synchronization of renal potassium excretion by the rhythm of cortisol secretion with the light-dark cycle. Three models of the circadian timing system were formalized.

Daily sodium and potassium excretion can be estimated by scheduled spot urine collections.

PubMed

Doenyas-Barak, Keren; Beberashvili, Ilia; Bar-Chaim, Adina; Averbukh, Zhan; Vogel, Ofir; Efrati, Shai

2015-01-01

The evaluation of sodium and potassium intake is part of the optimal management of hypertension, metabolic syndrome, renal stones, and other conditions. To date, no convenient method for its evaluation exists, as the gold standard method of 24-hour urine collection is cumbersome and often incorrectly performed, and methods that use spot or shorter collections are not accurate enough to replace the gold standard. The aim of this study was to evaluate the correlation and agreement between a new method that uses multiple-scheduled spot urine collection and the gold standard method of 24-hour urine collection. The urine sodium or potassium to creatinine ratios were determined for four scheduled spot urine samples. The mean ratios of the four spot samples and the ratios of each of the single spot samples were corrected for estimated creatinine excretion and compared to the gold standard. A significant linear correlation was demonstrated between the 24-hour urinary solute excretions and estimated excretion evaluated by any of the scheduled spot urine samples. The correlation of the mean of the four spots was better than for any of the single spots. Bland-Altman plots showed that the differences between these measurements were within the limits of agreement. Four scheduled spot urine samples can be used as a convenient method for estimation of 24-hour sodium or potassium excretion. © 2015 S. Karger AG, Basel.

Urinary excretion of adrenal steroids, catecholamines and electrolytes in man, before and after acclimatization to cold in Antarctica

PubMed Central

Budd, G. M.; Warhaft, N.

1970-01-01

1. Urine samples were collected from four men before and during test cold exposures in Melbourne, Australia, and Mawson, Antarctica. Changes in the response of body temperature to the test exposures showed that the men had acclimatized to cold at Mawson. 2. Excretion rates of 17-hydroxycorticosteroids and 17-ketosteroids were significantly greater at Mawson than in Melbourne, in both the pre-exposure and exposure periods. 3. Excretion rates of noradrenaline, adrenaline, sodium, potassium and creatinine did not differ significantly between Mawson and Melbourne, nor did urine flow rates. 4. During the cold exposure significant increases occurred, to the same extent at Mawson as in Melbourne, in urine flow rate and in all measured urinary constituents except creatinine. PMID:5501486

Low sodium intake does not impair renal compensation of hypoxia-induced respiratory alkalosis.

PubMed

Höhne, Claudia; Boemke, Willehad; Schleyer, Nora; Francis, Roland C; Krebs, Martin O; Kaczmarczyk, Gabriele

2002-05-01

Acute hypoxia causes hyperventilation and respiratory alkalosis, often combined with increased diuresis and sodium, potassium, and bicarbonate excretion. With a low sodium intake, the excretion of the anion bicarbonate may be limited by the lower excretion rate of the cation sodium through activated sodium-retaining mechanisms. This study investigates whether the short-term renal compensation of hypoxia-induced respiratory alkalosis is impaired by a low sodium intake. Nine conscious, tracheotomized dogs were studied twice either on a low-sodium (LS = 0.5 mmol sodium x kg body wt-1 x day-1) or high-sodium (HS = 7.5 mmol sodium x kg body wt-1 x day-1) diet. The dogs breathed spontaneously via a ventilator circuit during the experiments: first hour, normoxia (inspiratory oxygen fraction = 0.21); second to fourth hour, hypoxia (inspiratory oxygen fraction = 0.1). During hypoxia (arterial PO2 34.4 +/- 2.1 Torr), plasma pH increased from 7.37 +/- 0.01 to 7.48 +/- 0.01 (P < 0.05) because of hyperventilation (arterial PCO2 25.6 +/- 2.4 Torr). Urinary pH and urinary bicarbonate excretion increased irrespective of the sodium intake. Sodium excretion increased more during HS than during LS, whereas the increase in potassium excretion was comparable in both groups. Thus the quick onset of bicarbonate excretion within the first hour of hypoxia-induced respiratory alkalosis was not impaired by a low sodium intake. The increased sodium excretion during hypoxia seems to be combined with a decrease in plasma aldosterone and angiotensin II in LS as well as in HS dogs. Other factors, e.g., increased mean arterial blood pressure, minute ventilation, and renal blood flow, may have contributed.

Socioeconomic Status Associated With Urinary Sodium and Potassium Excretion in Japan: NIPPON DATA2010.

PubMed

Miyagawa, Naoko; Okuda, Nagako; Nakagawa, Hideaki; Takezaki, Toshiro; Nishi, Nobuo; Takashima, Naoyuki; Fujiyoshi, Akira; Ohkubo, Takayoshi; Kadota, Aya; Okamura, Tomonori; Ueshima, Hirotsugu; Okayama, Akira; Miura, Katsuyuki

2018-01-01

Although socioeconomic status (SES) may affect food and nutrient intakes, few studies have reported on sodium (Na) and potassium (K) intakes among individuals with various SESs in Japan. We investigated associations of SES with Na and K intake levels using urinary specimens in a representative Japanese population. This was a cross-sectional study of 2,560 men and women (the NIPPON DATA2010 cohort) who participated in the National Health and Nutrition Survey Japan in 2010. Casual urine was used to calculate estimated excretion in 24-hour urinary Na (E24hr-Na) and K (E24hr-K). The urinary sodium-to-potassium (Na/K) ratio was calculated from casual urinary electrolyte values. An analysis of covariance was performed to investigate associations of aspects of SES, including equivalent household expenditure (EHE), educational attainment, and job category, with E24hr-Na, E24hr-K, and the Na/K ratio for men and women separately. A stratified analysis was performed on educational attainment and the job category for younger (<65 years) and older (≥65 years) participants. In men and women, average E24hr-Na was 176.2 mmol/day and 172.3, average E24hr-K was 42.5 and 41.3, and the average Na/K ratio was 3.61 and 3.68, respectively. Lower EHE was associated with a higher Na/K ratio in women and lower E24hr-K in men and women. A shorter education was associated with a higher Na/K ratio in women and younger men, and lower E24hr-K in older men and women. Lower EHE and a shorter education were associated with a lower K intake and higher Na/K ratio estimated from casual urine specimens in Japanese men and women.

Demographic, dietary, and urinary factors and 24-h urinary calcium excretion.

PubMed

Taylor, Eric N; Curhan, Gary C

2009-12-01

Higher urinary calcium is a risk factor for nephrolithiasis. This study delineated associations between demographic, dietary, and urinary factors and 24-h urinary calcium. Cross-sectional studies were conducted of 2201 stone formers (SF) and 1167 nonstone formers (NSF) in the Health Professionals Follow-up Study (men) and Nurses' Health Studies I and II (older and younger women). Median urinary calcium was 182 mg/d in men, 182 mg/d in older women, and 192 mg/d in younger women. Compared with NSF, urinary calcium as a fraction of calcium intake was 33 to 38% higher in SF (P values < or =0.01). In regression analyses, participants were combined because associations with urinary calcium were similar in each cohort and in SF and NSF. After multivariate adjustment, participants in the highest quartile of calcium intake excreted 18 mg/d more urinary calcium than those in the lowest (P trend =0.01). Caffeine and family history of nephrolithiasis were positively associated, whereas urinary potassium, thiazides, gout, and age were inversely associated, with urinary calcium. After multivariate adjustment, participants in the highest quartiles of urinary magnesium, sodium, sulfate, citrate, phosphorus, and volume excreted 71 mg/d, 37 mg/d, 44 mg/d, 61 mg/d, 37 mg/d, and 24 mg/d more urinary calcium, respectively, than participants in the lowest (P values trend < or =0.01). Intestinal calcium absorption and/or negative calcium balance is greater in SF than NSF. Higher calcium intakes at levels typically observed in free-living individuals are associated with only small increases in urinary calcium.

Metabolic responses to high protein diet in Korean elite bodybuilders with high-intensity resistance exercise.

PubMed

Kim, Hyerang; Lee, Saningun; Choue, Ryowon

2011-07-04

High protein diet has been known to cause metabolic acidosis, which is manifested by increased urinary excretion of nitrogen and calcium. Bodybuilders habitually consumed excessive dietary protein over the amounts recommended for them to promote muscle mass accretion. This study investigated the metabolic response to high protein consumption in the elite bodybuilders. Eight elite Korean bodybuilders within the age from 18 to 25, mean age 21.5 ± 2.6. For data collection, anthropometry, blood and urinary analysis, and dietary assessment were conducted. They consumed large amounts of protein (4.3 ± 1.2 g/kg BW/day) and calories (5,621.7 ± 1,354.7 kcal/day), as well as more than the recommended amounts of vitamins and minerals, including potassium and calcium. Serum creatinine (1.3 ± 0.1 mg/dl) and potassium (5.9 ± 0.8 mmol/L), and urinary urea nitrogen (24.7 ± 9.5 mg/dl) and creatinine (2.3 ± 0.7 mg/dl) were observed to be higher than the normal reference ranges. Urinary calcium (0.3 ± 0.1 mg/dl), and phosphorus (1.3 ± 0.4 mg/dl) were on the border of upper limit of the reference range and the urine pH was in normal range. Increased urinary excretion of urea nitrogen and creatinine might be due to the high rates of protein metabolism that follow high protein intake and muscle turnover. The obvious evidence of metabolic acidosis in response to high protein diet in the subjects with high potassium intake and intensive resistance exercise were not shown in this study results. However, this study implied that resistance exercise with adequate mineral supplementation, such as potassium and calcium, could reduce or offset the negative effects of protein-generated metabolic changes. This study provides preliminary information of metabolic response to high protein intake in bodybuilders who engaged in high-intensity resistance exercise. Further studies will be needed to determine the effects of the intensity of exercise and the level of mineral intakes, especially potassium and calcium, which have a role to maintain acid-base homeostasis, on protein metabolism in large population of bodybuilders.

Shakuyaku-kanzo-to induces pseudoaldosteronism characterized by hypokalemia, rhabdomyolysis, metabolic alkalosis with respiratory compensation, and increased urinary cortisol levels.

PubMed

Kinoshita, Hiroyuki; Okabayashi, Misako; Kaneko, Masakazu; Yasuda, Mutsuko; Abe, Keisuke; Machida, Akira; Ohkubo, Takuya; Kamata, Tomoyuki; Yakushiji, Fumiatsu

2009-04-01

Licorice, the primary ingredient of the Japanese herbal medicine shakuyaku-kanzo-to, can cause pseudoaldosteronism. Thus, shakuyaku-kanzo-to can cause this condition. A 79-year-old woman was brought to the emergency room. She had been experiencing general fatigue, numbness in the hands, and weakness in the lower limbs and could not stand up without assistance. She presented with hypokalemia (potassium level, 1.7 mEq/L), increased urinary excretion of potassium (fractional excretion of K, 21.2%), abnormalities on an electrocardiogram (flat T waves in II, III, AVF, and V1-6), rhabdomyolysis (creatine kinase level, 28,376 U/L), myopathy, metabolic alkalosis with respiratory compensation (O(2) flow rate, 2 L/min; pH, 7.473; pco(2), 61.0 mm Hg; po(2), 78.0 mm Hg; HCO(3), 44.1 mmol/L), hypertension (174/93 mm Hg), hyperglycemia (blood glucose level, 200-300 mg/dL), frequent urination, suppressed plasma renin activity (0.1 ng/mL/hour), decreased aldosterone levels (2.6 ng/dL), and increased urinary cortisol levels (600.6 microg/day; reference range, 26.0-187.0 microg/day). In this case, the observed reduction in the urinary cortisol levels, from 600.6 to 37.8 microg/day, led to a definitive diagnosis of pseudoaldosteronism instead of the apparent mineralocorticoid excess syndrome. Discontinuing shakuyaku-kanzo-to treatment and administering spironolactone and potassium proved effective in improving the patient's condition. Medical practitioners prescribing shakuyaku-kanzo-to should take into account the association between licorice, which is its main ingredient, and pseudoaldosteronism.

Measurement error corrected sodium and potassium intake estimation using 24-hour urinary excretion.

PubMed

Huang, Ying; Van Horn, Linda; Tinker, Lesley F; Neuhouser, Marian L; Carbone, Laura; Mossavar-Rahmani, Yasmin; Thomas, Fridtjof; Prentice, Ross L

2014-02-01

Epidemiological studies of the association of sodium and potassium intake with cardiovascular disease risk have almost exclusively relied on self-reported dietary data. Here, 24-hour urinary excretion assessments are used to correct the dietary self-report data for measurement error under the assumption that 24-hour urine recovery provides a biomarker that differs from usual intake according to a classical measurement model. Under this assumption, dietary self-reports underestimate sodium by 0% to 15%, overestimate potassium by 8% to 15%, and underestimate sodium/potassium ratio by ≈20% using food frequency questionnaires, 4-day food records, or three 24-hour dietary recalls in Women's Health Initiative studies. Calibration equations are developed by linear regression of log-transformed 24-hour urine assessments on corresponding log-transformed self-report assessments and several study subject characteristics. For each self-report method, the calibration equations turned out to depend on race and age and strongly on body mass index. After adjustment for temporal variation, calibration equations using food records or recalls explained 45% to 50% of the variation in (log-transformed) 24-hour urine assessments for sodium, 60% to 70% of the variation for potassium, and 55% to 60% of the variation for sodium/potassium ratio. These equations may be suitable for use in epidemiological disease association studies among postmenopausal women. The corresponding signals from food frequency questionnaire data were weak, but calibration equations for the ratios of sodium and potassium/total energy explained ≈35%, 50%, and 45% of log-biomarker variation for sodium, potassium, and their ratio, respectively, after the adjustment for temporal biomarker variation and may be suitable for cautious use in epidemiological studies. Clinical Trial Registration- URL: www.clinicaltrials.gov. Unique identifier: NCT00000611.

The comparison of the diuretic and natriuretic efficacy of continuous and bolus intravenous furosemide in patients with chronic kidney disease.

PubMed

Sanjay, Srinivas; Annigeri, Rajeev A; Seshadri, Rajagopalan; Rao, Budithi Subba; Prakash, Kowdle C; Mani, Muthu Krishna

2008-06-01

To compare natriuretic, kaliuretic, diuretic and free water clearance efficacy of continuous versus bolus intravenous furosemide administration in patients with chronic renal insufficiency. In a prospective randomized cross-over trial, 42 patients of chronic renal insufficiency were randomized to receive the same dose of intravenous furosemide as bolus and continuous infusion. The effects of bolus and intravenous administration of furosemide on the volume of urine, sodium and potassium excretion were assessed. Mean age was 53.6 +/- 14 years and 23 (55%) were male. The mean modification of diet in renal disease glomerular filtration rate was 20.5 +/- 17 mL/min per 1.73 m(2). The urinary excretion of sodium in intravenous bolus and infusion was 98.1 +/- 78 and 114.4 +/- 100 mmol, respectively (P = 0.001). Total urinary volume following bolus and infusion of furosemide was 1064 +/- 627 and 1170 +/- 764 mL, respectively (0.001). The excretion of potassium was similar in bolus (15.8 +/- 16.6) and infusion (14.3 +/- 9) administration (P = 0.11). The fractional excretion of sodium was higher following infusion (16.63 +/- 16.1) than bolus administration (12.87 +/- 9) of furosemide (P = 0.016). Continuous intravenous infusion of furosemide has significantly better natriuretic and diuretic effect than bolus administration of the same dose of the drug in patients with advanced chronic renal insufficiency.

Estimating 24-h urinary sodium/potassium ratio from casual ('spot') urinary sodium/potassium ratio: the INTERSALT Study.

PubMed

Iwahori, Toshiyuki; Miura, Katsuyuki; Ueshima, Hirotsugu; Chan, Queenie; Dyer, Alan R; Elliott, Paul; Stamler, Jeremiah

2017-10-01

Association between casual and 24-h urinary sodium-to-potassium (Na/K) ratio is well recognized, although it has not been validated in diverse demographic groups. Our aim was to assess utility across and within populations of casual urine to estimate 24-h urinary Na/K ratio using data from the INTERSALT Study. The INTERSALT Study collected cross-sectional standardized data on casual urinary sodium and potassium and also on timed 24-h urinary sodium and potassium for 10 065 individuals from 52 population samples in 32 countries (1985-87). Pearson correlation coefficients and agreement were computed for Na/K ratio of casual urine against 24-h urinary Na/K ratio both at population and individual levels. Pearson correlation coefficients relating means of 24-h urine and casual urine Na/K ratio were r = 0.96 and r = 0.69 in analyses across populations and individuals, respectively. Correlations of casual urine Na/creatinine and K/creatinine ratios with 24-h urinary Na and K excretion, respectively, were lower than correlation of casual and 24-h urinary Na/K ratio in analyses across populations and individuals. The bias estimate with the Bland-Altman method, defined as the difference between Na/K ratio of 24-h urine and casual urine, was approximately 0.4 across both populations and individuals. Spread around, the mean bias was higher for individuals than populations. With appropriate bias correction, casual urine Na/K ratio may be a useful, low-burden alternative method to 24-h urine for estimation of population urinary Na/K ratio. It may also be applicable for assessment of the urinary Na/K ratio of individuals, with use of repeated measurements to reduce measurement error and increase precision. © The Author 2016. Published by Oxford University Press on behalf of the International Epidemiological Association

Population Pharmacokinetic-Pharmacodynamic Model of Oral Fludrocortisone and Intravenous Hydrocortisone in Healthy Volunteers.

PubMed

Hamitouche, Noureddine; Comets, Emmanuelle; Ribot, Mégane; Alvarez, Jean-Claude; Bellissant, Eric; Laviolle, Bruno

2017-05-01

This study aimed at describing the pharmacokinetics and the concentration-effect relationships of fludrocortisone and hydrocortisone on urinary sodium/potassium excretion in healthy volunteers. This was a placebo-controlled, randomized, double blind, crossover study, of oral fludrocortisone and intravenous hydrocortisone, given alone or in combination, in 12 healthy male volunteers. Nonlinear mixed-effects modeling was used to describe the pharmacokinetics and pharmacokinetic-pharmacodynamic relationships on urinary sodium/potassium ratio for each drug. A one-compartment model was used to describe fludrocortisone and hydrocortisone pharmacokinetics. Mean plasma half-life was 1.40 h (95%CI [0.80;2.10]) for fludrocortisone and 2.10 h (95%CI [1.78;2.40]) for hydrocortisone. Clearance was 40.8 L/h (95%CI [33.6;48]) for fludrocortisone and 30 L/h (95%CI [25.3;34.7]) for hydrocortisone. An indirect response model was used to describe effects on urinary sodium/potassium ratio. Fludrocortisone plasma concentrations showed a wider inter-individual dispersion than hydrocortisone plasma concentrations. Urinary sodium/potassium ratio variability was also higher with fludrocortisone as compared to hydrocortisone. The plasma concentration of drug producing 50% of maximal inhibition of urinary sodium/potassium (IC 50 ) was about 200 times lower for fludrocortisone (0.08 μg/L, 95%CI [0.035;0.125]) than for hydrocortisone (16.7 μg/L, 95%CI [10.5;22.9]). Simulations showed that a 4-time per day administration regimen allow to achieve steady fludrocortisone plasma concentrations with stable decrease in urinary sodium/potassium ratio after the second administration of fludrocortisone. Fludrocortisone and hydrocortisone have short and similar plasma elimination half-lives in healthy subjects. Fludrocortisone plasma concentrations and effect on urinary sodium/potassium ratio had a higher inter-individual variability as compared to hydrocortisone. The administration regimen of fludrocortisone should be reconsidered.

Association between Parent and Child Dietary Sodium and Potassium Intakes as Assessed by 24-h Urinary Excretion.

PubMed

Service, Carrie; Grimes, Carley; Riddell, Lynn; He, Feng; Campbell, Karen; Nowson, Caryl

2016-04-01

The aim of this study was to assess the association between parent and child sodium (Na) and potassium (K) intake as assessed by 24-h urinary excretion (24hUE). Primary school children and their parent(s) provided one 24-h urine sample and information on cooking and children's discretionary salt use. Valid urine samples were provided by 108 mothers (mean age 41.8 (5.1) (SD) years, Na 120 (45) mmol/day) (7.0 g/day salt equivalent) and 40 fathers (44.4 (4.9) years, Na 152 (49) mmol/day (8.9 g/day salt), and 168 offspring (51.8% male, age 9.1 (2.0) years, Na 101 (47) mmol/day (5.9 g/day salt). When adjusted for parental age, child age and gender a 17 mmol/day Na (1 g/day salt) increase in mother's 24hUE was associated with a 3.4 mmol/day Na (0.2 g/day salt) increase in child's salt 24hUE (p = 0.04) with no association observed between father and child. Sixty-seven percent of parents added salt during cooking and 37% of children added salt at the table. Children who reported adding table salt had higher urinary excretion than those who did not (p = 0.01). The association between mother and child Na intake may relate to the consumption of similar foods and highlights the importance of the home environment in influencing total dietary sodium intake.

Diuretic activity of Maydis stigma extract in rats.

PubMed

Maksimović, Z; Dobrić, S; Kovacević, N; Milovanović, Z

2004-12-01

Maydis stigma (corn silk) is a herbal drug reputed for the treatment of urinary ailments in various traditional medicine systems. To determine its influence on urinary volume and the excretion of sodium, potassium and chloride, 5% and 10% decoctions were administered daily to adult male Wistar rats for eight days. The concentration of electrolytes and urea in plasma, the influence of treatment on urinary pH value as well as creatinine clearance were also investigated. Daily oral administration of 5% decoction at the dose of 10 ml/kg led to a significant and acute diuresis in rats, reaching the peak value in the first 24 h of treatment. Over a similar period, application of 10% decoction did not affect urinary excretion of water, but significantly increased the pH value of excreted urine. A significant decrease in sodium and chloride plasma levels was observed in both treated groups. The creatinine clearance was markedly increased after the treatment with both extracts. Our findings indicate that the diuretic effect of 5% aqueous Maydis stigma extract is in accordance with the increase in glomerular filtration rate and inhibition of sodium and chloride tubular reabsorption, caused a by still unidentified intrinsic factor, but not the salt-loading effect.

Demographic, Dietary, and Urinary Factors and 24-h Urinary Calcium Excretion

PubMed Central

Curhan, Gary C.

2009-01-01

Background and objectives: Higher urinary calcium is a risk factor for nephrolithiasis. This study delineated associations between demographic, dietary, and urinary factors and 24-h urinary calcium. Design, setting, participants, & measurements: Cross-sectional studies were conducted of 2201 stone formers (SF) and 1167 nonstone formers (NSF) in the Health Professionals Follow-up Study (men) and Nurses' Health Studies I and II (older and younger women). Results: Median urinary calcium was 182 mg/d in men, 182 mg/d in older women, and 192 mg/d in younger women. Compared with NSF, urinary calcium as a fraction of calcium intake was 33 to 38% higher in SF (P values ≤0.01). In regression analyses, participants were combined because associations with urinary calcium were similar in each cohort and in SF and NSF. After multivariate adjustment, participants in the highest quartile of calcium intake excreted 18 mg/d more urinary calcium than those in the lowest (P trend =0.01). Caffeine and family history of nephrolithiasis were positively associated, whereas urinary potassium, thiazides, gout, and age were inversely associated, with urinary calcium. After multivariate adjustment, participants in the highest quartiles of urinary magnesium, sodium, sulfate, citrate, phosphorus, and volume excreted 71 mg/d, 37 mg/d, 44 mg/d, 61 mg/d, 37 mg/d, and 24 mg/d more urinary calcium, respectively, than participants in the lowest (P values trend ≤0.01). Conclusions: Intestinal calcium absorption and/or negative calcium balance is greater in SF than NSF. Higher calcium intakes at levels typically observed in free-living individuals are associated with only small increases in urinary calcium. PMID:19820135

Effect of Ramadan fasting on urinary risk factors for calculus formation.

PubMed

Miladipour, Amir Hossein; Shakhssalim, Nasser; Parvin, Mahmoud; Azadvari, Mohaddeseh

2012-01-01

Even though dehydration could aggravate formation of urinary calculi, the effects of fluid and food restriction on calculus formation is not thoroughly defined. The purpose of this study is to evaluate the effects of fluid and food restriction in Ramadan fasting on urinary factors in kidney and urinary calculus formation. Fifty-seven men aged 30 to 55 years old, including 37 recurrent calcium calculus formers and 20 with no history of kidney calculi were evaluated for blood tests, ultrasonography investigations, urinalysis, urine culture, and also 24-hour urine collection test. Metabolites including calcium, oxalate, citrate, uric acid, magnesium, phosphate, potassium, sodium, and creatinine were measured before and during Ramadan fasting. The values of calculus-precipitating solutes as well as inhibitory factors were documented thoroughly. Total excretion of calcium, phosphate, and magnesium in 24-hour urine and also urine volume during fasting were significantly lower than those in the nonfasting period. Urine concentration of calcium during fasting was significantly lower than nonfasting (P < .001). Urine concentrations of uric acid, citrate, phosphate, sodium, and potassium during fasting were significantly higher than nonfasting. Uric acid supersaturation was accentuated, and calcium phosphate supersaturation was decreased significantly during fasting. There was no significant increase in calcium oxalate supersaturation during the fasting period. Fasting during Ramadan has different effects on total excretion and concentrations of urinary precipitate and inhibitory factors contributing to calculus formation. We did not find enough evidence in favor of increased risks of calculus formation during Ramadan fasting.

Limitation on the use of amiloride in early renal failure.

PubMed

Knauf, H; Reuter, K; Mutschler, E

1985-01-01

The effect of a single oral dose of 10 mg amiloride was studied on urinary excretion of Na+, K+, Ca++ and Mg++ in healthy subjects and in patients with varying degrees of renal impairment. Amiloride produced a moderate diuresis and sodium excretion, and a slight calciuresis. Urinary excretion of potassium was significantly reduced as compared to the controls. Despite its diuretic and natriuretic effects, amiloride did not change the excretion of Mg++ as compared to the pretreatment period. When the creatinine clearance was below 50 ml/min, the net excretion of Na+ and Ca++ was drastically reduced. However, K+ retention and neutrality of Mg++ excretion were maintained down to end-stage renal disease. In the healthy volunteers the mean elimination half-life of amiloride was 20 h, and it rose to about 100 h in end-stage renal disease. This was because about 3/4 of native amiloride was eliminated through the kidney. Nonrenal elimination of amiloride was calculated to amount to only 1/4 of the total elimination. Therefore, the anticaliuretic amiloride is a valuable comedication in subjects with normal kidney function to prevent K+ and Mg++ loss. However, its use is hazardous if plasma creatinine is raised.

Metabolic Characteristics and Risks Associated with Stone Recurrence in Korean Young Adult Stone Patients.

PubMed

Kang, Ho Won; Seo, Sung Pil; Kim, Won Tae; Kim, Yong-June; Yun, Seok-Joong; Kim, Wun-Jae; Lee, Sang-Cheol

2017-08-01

The aim of this study was to assess the metabolic characteristics and risks of stone recurrence in young adult stone patients in Korea. The medical records of 1532 patients presenting with renal or ureteric stones at our stone clinic between 1994 and 2015 were retrospectively reviewed. Patients were grouped according to age (young adult, 18-29 years; intermediate onset, 30-59 years; old age, ≥60 years) at first presentation, and measurements of clinicometabolic characteristics and risks of stone recurrence were compared. Overall, excretion of urinary stone-forming substances was highest in the intermediate onset group, followed by the young adult and old age groups. Importantly, excretion of urinary citrate was lowest in the young adult group. Kaplan-Meier analyses identified a significant difference between the three age groups in terms of stone recurrence (log rank test, p < 0.001). Multivariate Cox regression analyses revealed that age at first stone presentation was an independent risk factor for stone recurrence. Urinary citrate excretion was an independent risk factor for stone recurrence in young adult stone patients. Younger age (18-29 years) at first stone presentation was a significant risk factor for stone recurrence, and urinary citrate excretion was an independent risk factor affecting recurrence in this group. Metabolic evaluation and potassium citrate therapy should be considered for young adult stone patients to prevent recurrence.

Adequate intake of potassium does not cause hyperkalemia in hypertensive individuals taking medications that antagonize the renin angiotensin aldosterone system.

PubMed

Malta, Daniela; Arcand, JoAnne; Ravindran, Anju; Floras, Vanessa; Allard, Johane P; Newton, Gary E

2016-10-01

Reduced potassium excretion caused by angiotensin-converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) may increase the risk of hyperkalemia (serum potassium concentration >5 mmol/L) in the setting of increased potassium intake. The purpose of this study was to assess the effect of increasing dietary potassium on serum potassium concentration in hypertensive individuals with normal renal function treated with an ACEi or ARB. We hypothesized that an increase in dietary potassium would not provoke hyperkalemia in this population despite treatment with either an ACEi or ARB. We conducted a controlled, parallel-design clinical trial in 20 hypertensive subjects with normal renal function treated with an ACEi or ARB, with random assignment to a usual diet or a high-potassium diet (HKD). Fruit and vegetable intake was used to increase potassium intake. Serum potassium concentration, 3-d food records, and 24-h urine collections were completed at baseline and 4 wk. In the usual-diet group there were no statistically significant differences for potassium excretion, intake, or serum levels at end of study compared with baseline. The HKD group had significant differences in urinary potassium excretion (83 ± 26 mmol/d at baseline compared with 109 ± 35 mmol/d at 4 wk, P = 0.01) and dietary potassium intake (3775 ± 1189 mg/d at baseline compared with 5212 ± 1295 mg/d at 4 wk, P = 0.02). Despite increased potassium intake in the HKD group, serum potassium concentrations did not significantly increase from baseline at midpoint or end of study (4.1 ± 0.6, 4.3 ± 0.3, and 4.2 ± 0.4 mmol/L, respectively). This study demonstrates that an increase in dietary potassium over a 4-wk period is safe in hypertensive subjects who have normal renal function and are receiving ACEi and/or ARB therapy. This trial was registered at www.clinicaltrials.gov as NCT02759367. © 2016 American Society for Nutrition.

Metabolic responses to high protein diet in Korean elite bodybuilders with high-intensity resistance exercise

PubMed Central

2011-01-01

Background High protein diet has been known to cause metabolic acidosis, which is manifested by increased urinary excretion of nitrogen and calcium. Bodybuilders habitually consumed excessive dietary protein over the amounts recommended for them to promote muscle mass accretion. This study investigated the metabolic response to high protein consumption in the elite bodybuilders. Methods Eight elite Korean bodybuilders within the age from 18 to 25, mean age 21.5 ± 2.6. For data collection, anthropometry, blood and urinary analysis, and dietary assessment were conducted. Results They consumed large amounts of protein (4.3 ± 1.2 g/kg BW/day) and calories (5,621.7 ± 1,354.7 kcal/day), as well as more than the recommended amounts of vitamins and minerals, including potassium and calcium. Serum creatinine (1.3 ± 0.1 mg/dl) and potassium (5.9 ± 0.8 mmol/L), and urinary urea nitrogen (24.7 ± 9.5 mg/dl) and creatinine (2.3 ± 0.7 mg/dl) were observed to be higher than the normal reference ranges. Urinary calcium (0.3 ± 0.1 mg/dl), and phosphorus (1.3 ± 0.4 mg/dl) were on the border of upper limit of the reference range and the urine pH was in normal range. Conclusions Increased urinary excretion of urea nitrogen and creatinine might be due to the high rates of protein metabolism that follow high protein intake and muscle turnover. The obvious evidence of metabolic acidosis in response to high protein diet in the subjects with high potassium intake and intensive resistance exercise were not shown in this study results. However, this study implied that resistance exercise with adequate mineral supplementation, such as potassium and calcium, could reduce or offset the negative effects of protein-generated metabolic changes. This study provides preliminary information of metabolic response to high protein intake in bodybuilders who engaged in high-intensity resistance exercise. Further studies will be needed to determine the effects of the intensity of exercise and the level of mineral intakes, especially potassium and calcium, which have a role to maintain acid-base homeostasis, on protein metabolism in large population of bodybuilders. PMID:21722409

Noncitrus alkaline fruit: a dietary alternative for the treatment of hypocitraturic stone formers.

PubMed

Baia, Leandro da Cunha; Baxmann, Alessandra Calábria; Moreira, Silvia Regina; Holmes, Ross Philip; Heilberg, Ita Pfeferman

2012-09-01

Fruits and vegetables are natural suppliers of potassium, bicarbonate, or bicarbonate precursors such as citrate, malate and others-hence, possessing potential effects on citraturia. We aimed to compare the acute effects of a noncitrus (melon) fruit vs citric ones (orange and lime) on citraturia and other lithogenic parameters. Two-hour urine samples were collected from 30 hypocitraturic stone-forming patients after an overnight fast and 2, 4, and 6 hours after the consumption of 385 mL (13 oz) of either freshly squeezed orange juice (n=10), freshly blended melon juice (n=10), or freshly squeezed lime juice (n=10). Urinary citrate, potassium, pH, and other lithogenic parameters were determined and net gastrointestinal alkali absorption (NGIA) was calculated. Potential renal acid load (PRAL) and pH from juices were determined. Significant and comparable increases of mean urinary citrate were observed in all groups, whereas mean urinary potassium, pH, and NGIA were significantly increased only after consumption of melon and orange juices. The pH of melon juice was higher and the PRAL value was more negative compared with orange juice, indicating a higher alkalinity. These findings suggested that melon, a noncitrus source of potassium, citrate, and malate, yielded an increase in urinary citrate excretion equivalent to that provided by orange, and hence represents another dietary alternative for the treatment of hypocitraturic stone-formers. Despite its low potassium content, lime also produced comparable increases in citraturia possibly because of its high citric acid content.

Association of urinary sodium and potassium excretion with blood pressure.

PubMed

Mente, Andrew; O'Donnell, Martin J; Rangarajan, Sumathy; McQueen, Matthew J; Poirier, Paul; Wielgosz, Andreas; Morrison, Howard; Li, Wei; Wang, Xingyu; Di, Chen; Mony, Prem; Devanath, Anitha; Rosengren, Annika; Oguz, Aytekin; Zatonska, Katarzyna; Yusufali, Afzal Hussein; Lopez-Jaramillo, Patricio; Avezum, Alvaro; Ismail, Noorhassim; Lanas, Fernando; Puoane, Thandi; Diaz, Rafael; Kelishadi, Roya; Iqbal, Romaina; Yusuf, Rita; Chifamba, Jephat; Khatib, Rasha; Teo, Koon; Yusuf, Salim

2014-08-14

Higher levels of sodium intake are reported to be associated with higher blood pressure. Whether this relationship varies according to levels of sodium or potassium intake and in different populations is unknown. We studied 102,216 adults from 18 countries. Estimates of 24-hour sodium and potassium excretion were made from a single fasting morning urine specimen and were used as surrogates for intake. We assessed the relationship between electrolyte excretion and blood pressure, as measured with an automated device. Regression analyses showed increments of 2.11 mm Hg in systolic blood pressure and 0.78 mm Hg in diastolic blood pressure for each 1-g increment in estimated sodium excretion. The slope of this association was steeper with higher sodium intake (an increment of 2.58 mm Hg in systolic blood pressure per gram for sodium excretion >5 g per day, 1.74 mm Hg per gram for 3 to 5 g per day, and 0.74 mm Hg per gram for <3 g per day; P<0.001 for interaction). The slope of association was steeper for persons with hypertension (2.49 mm Hg per gram) than for those without hypertension (1.30 mm Hg per gram, P<0.001 for interaction) and was steeper with increased age (2.97 mm Hg per gram at >55 years of age, 2.43 mm Hg per gram at 45 to 55 years of age, and 1.96 mm Hg per gram at <45 years of age; P<0.001 for interaction). Potassium excretion was inversely associated with systolic blood pressure, with a steeper slope of association for persons with hypertension than for those without it (P<0.001) and a steeper slope with increased age (P<0.001). In this study, the association of estimated intake of sodium and potassium, as determined from measurements of excretion of these cations, with blood pressure was nonlinear and was most pronounced in persons consuming high-sodium diets, persons with hypertension, and older persons. (Funded by the Heart and Stroke Foundation of Ontario and others.).

Lower potassium intake is associated with increased wave reflection in young healthy adults

PubMed Central

2014-01-01

Background Increased potassium intake has been shown to lower blood pressure (BP) even in the presence of high sodium consumption however the role of dietary potassium on vascular function has received less attention. The aim of this study was to evaluate the relationship between habitual intake of sodium (Na) and potassium (K) and measures of arterial stiffness and wave reflection. Methods Thirty-six young healthy adults (21 M, 15 F; 24 ± 0.6 yrs; systolic BP 117 ± 2; diastolic BP 63 ± 1 mmHg) recorded their dietary intake for 3 days and collected their urine for 24 hours on the 3rd day. Carotid-femoral pulse wave velocity (PWV) and the synthesis of a central aortic pressure waveform (by radial artery applanation tonometry and generalized transfer function) were performed. Aortic augmentation index (AI), an index of wave reflection, was calculated from the aortic pressure waveform. Results Subjects consumed an average of 2244 kcals, 3763 mg Na, and 2876 mg of K. Average urinary K excretion was 67 ± 5.3 mmol/24 hr, Na excretion was 157 ± 11 mmol/24 hr and the average Na/K excretion ratio was 2.7 ± 0.2. An inverse relationship between AI and K excretion was found (r = -0.323; p < 0.05). A positive relationship between AI and the Na/K excretion ratio was seen (r = 0.318; p < 0.05) while no relationship was noted with Na excretion alone (r = 0.071; p > 0.05). Reflection magnitude, the ratio of reflected and forward waves, was significantly associated with the Na/K excretion ratio (r = 0.365; p <0.05) but not Na or K alone. PWV did not correlate with Na or the Na/K excretion ratio (p > 0.05) but showed an inverse relationship with K excretion (r = -0.308; p < 0.05). Conclusions These data suggest that lower potassium intakes are associated with greater wave reflection and stiffer arteries in young healthy adults. PMID:24775098

Safety and efficacy of oral DMSA therapy for children with autism spectrum disorders: Part A - Medical results

PubMed Central

Adams, James B; Baral, Matthew; Geis, Elizabeth; Mitchell, Jessica; Ingram, Julie; Hensley, Andrea; Zappia, Irene; Newmark, Sanford; Gehn, Eva; Rubin, Robert A; Mitchell, Ken; Bradstreet, Jeff; El-Dahr, Jane

2009-01-01

Background This study investigated the effect of oral dimercapto succinic acid (DMSA) therapy for children with autism spectrum disorders ages 3-8 years. Methods Phase 1 involved 65 children who received one round of DMSA (3 days). Participants who had high urinary excretion of toxic metals were selected to continue on to phase 2. In phase 2, 49 participants were randomly assigned in a double-blind design to receive an additional 6 rounds of either DMSA or placebo. Results DMSA greatly increased the excretion of lead, substantially increased excretion of tin and bismuth, and somewhat increased the excretion of thallium, mercury, antimony, and tungsten. There was some increase in urinary excretion of essential minerals, especially potassium and chromium. The Phase 1 single round of DMSA led to a dramatic normalization of RBC glutathione in almost all cases, and greatly improved abnormal platelet counts, suggesting a significant decrease in inflammation. Conclusion Overall, DMSA therapy seems to be reasonably safe, effective in removing several toxic metals (especially lead), dramatically effective in normalizing RBC glutathione, and effective in normalizing platelet counts. Only 1 round (3 days) was sufficient to improve glutathione and platelets. Additional rounds increased excretion of toxic metals. PMID:19852789

The relationship between sodium intake and some bone minerals and osteoporosis risk assessment instrument in postmenopausal women.

PubMed

Vafa, Mohammadreza; Soltani, Sepideh; Zayeri, Farid; Niroomand, Mahtab; Najarzadeh, Azadeh

2016-01-01

The results of the studies on the effects of sodium on bone metabolism have been inconsistent. There is no definitive answer to the question of whether sodium restriction can be associated with a lower incidence of osteoporosis. What reinforces the necessity of designing this study is the lack of findings with the approach of examining the effects of sodium on bone in our country. This was a cross-sectional study conducted on 185 retired female teachers aged 45 to 70. Sodium intake was evaluated using two methods: A 24-hour recall and a 12-hour urine sample. To assess bone health, ORAI index was calculated for each individual. Urinary calcium, phosphorus, potassium and serum vitamin D and PTH were measured as laboratory variables. To compare the general characteristics of the participants across tertiles of urinary sodium, the analysis of variance (ANOVA) was used for quantitative variables and the Chi-square test for categorical variables. Phosphorous, calcium and potassium urinary excretion rate increased with the increase in urinary sodium (p<0.05). However, the changes in serum vitamin D, and PTH levels across tertiles of urinary sodium were not significant. Changes in urinary sodium levels were not significant (p=0.933) in ORAI groups (sorted by rating). The relationship between urinary calcium and sodium was apparent in low calcium intake (r=0.415, p<0.001), but not in higher calcium intake (r=0.144, p=0.177). Although urinary calcium and potassium increased with the increase in sodium intake, no relationship was found between sodium and ORAI.

Effects of potassium chloride and potassium bicarbonate in the diet on urinary pH and mineral excretion of adult cats.

PubMed

Passlack, Nadine; Brenten, Thomas; Neumann, Konrad; Zentek, Jürgen

2014-03-14

Low dietary K levels have been associated with increasing renal Ca excretion in humans, indicating a higher risk of calcium oxalate (CaOx) urolith formation. Therefore, the present study aimed to investigate whether dietary K also affects the urine composition of cats. A total of eight adult cats were fed diets containing 0·31 % native K and 0·50, 0·75 and 1·00 % K from KCl or KHCO₃ and were evaluated for the effects of dietary K. High dietary K levels were found to elevate urinary K concentrations (P<0·001). Renal Ca excretion was higher in cats fed the KCl diets than in those fed the KHCO₃ diets (P=0·026), while urinary oxalate concentrations were generally lower in cats fed the KCl diets and only dependent on dietary K levels in cats fed the KHCO₃ diets (P<0·05). Fasting urine pH increased with higher dietary K levels (P=0·022), reaching values of 6·38 (1·00 % KCl) and 7·65 (1·00 % KHCO₃). K retention was markedly negative after feeding the cats with the basal diet (-197 mg/d) and the 0·50 % KCl diet (-131 mg/d), while the cats tended to maintain their balance on being fed the highest-KCl diet (-23·3 mg/d). In contrast, K from KHCO₃ was more efficiently retained (P=0·018), with K retention being between -82·5 and 52·5 mg/d. In conclusion, the dietary inclusion of KHCO₃ instead of KCl as K source could be beneficial for the prevention of CaOx urolith formation in cats, since there is an association between a lower renal Ca excretion and a generally higher urine pH. The utilisation of K is distinctly influenced by the K salt, which may be especially practically relevant when using diets with low K levels.

[INFLUENCE OF OLEAMIDE OF WATER AND ION TRANSPORT IN THE OSMOREGULATORY ORGANS].

PubMed

Shakhmatova, E I; Bogolepova, A E; Dubina, M V; Natochin, Yu V

2015-01-01

Application of oleamide (final concentration of 10 μM) at the skin basal surface of the frog, Rana temporaria L., augmented the short-circuit current (SCC) from 59.8 ± 2.5 to 78.2 ± 1.4 μA/cm2. Oleamide added to the serous membrane of the frog urinary bladder at a final dose of 1 μM induced more than 30-fold increase of osmotic permeability. The addition of arginine-vasotocin on the background of oleamide action further increased SCC across the isolated frog skin and osmotic permeability of the frog urinary bladder. Intraperitoneal injection of oleamide at a dose of 0.1 mM/100 g BW to water-loaded non-anesthetized Wistar rats decreased diuresis by 22%, enhanced solute-free water reabsorption and urinary sodium excretion by 31% and 55% respectively, but did not affect the renal potassium excretion. The results obtained provide evidence of similarity of oleamide and neurohypophyseal hormones effects on water and ion transport in epithelial cells of osmoregulatory organs in vertebrates.

Salt Intake and the Association with Blood Pressure in Young Iranian Children: First Report From the Middle East and North Africa

PubMed Central

Kelishadi, Roya; Gheisari, Alaleh; Zare, Narges; Farajian, Sanam; Shariatinejad, Keyvan

2013-01-01

Background: This study aimed to assess the salt intake of Iranian children, and to assess the correlation of urinary electrolytes excretion with blood pressure. Methods: This cross-sectional study was conducted in 2011-2012 among 3-10-year-old children, selected by multi-stage cluster sampling from urban and rural areas of Isfahan, Iran. The sodium (Na), potassium (K), and creatinine (Cr) were measured in a random sample of the children's first morning fasting urine. Three-day averages of dietary intakes were analyzed by the Nutritionist-4 software. Results: The mean (SD) of urinary Na was 177.17 (28.68) mEq/day without significant difference according to gender and living area. The mean (SD) dietary intakes of Na and K were 2017.76 (117.94) and 1119.06 (76.03) mg/day, respectively. Children of urban and rural areas consumed similar sources of salty foods (bread, cheese, and snacks) and had low intake of vegetables. No significant association was documented between urinary electrolytes excretions and blood pressure. Conclusions: This study, which to the best of our knowledge is the first of its kind in the Middle East and North Africa region, revealed that Iranian young children consume a large amount of sodium and small amount of potassium. The non-significant associations of electrolyte excretions with blood pressure may be because of the very young age group of participants. Given the development of preference to salt taste from early childhood, and the tracking of risk factors of chronic diseases from this age, reducing salt intake of young children should be emphasized. PMID:23671781

Effects on milk urea concentration, urine output, and drinking water intake from incremental doses of potassium bicarbonate fed to mid-lactation dairy cows.

PubMed

Eriksson, T; Rustas, B-O

2014-07-01

Large variation exists in the potassium content of dairy cow feeds and also within a feed type due to soil type and fertilization. Increased ration K concentration causes a subsequent increase in urinary volume and could be expected to also lower milk urea concentration. Six multiparous mid-lactation Swedish Red dairy cows, all fitted with rumen cannulas, were subjected to 3 different levels of K intake in a Latin square experiment with three 2-wk periods to evaluate the effects on concentrations of milk urea and rumen ammonia, urinary output, and drinking water intake. The treatments were achieved by K supplementation on top of a low-K basal ration fed at individual allowances fixed throughout the experiment. The basal ration, consumed at 20.2 kg of dry matter (DM)/d, provided 165 g of crude protein/kg of DM and consisted of grass silage, concentrates, and urea in the proportions 39.3:60.0:0.7 on a DM basis. Potassium bicarbonate supplementation was 0, 616, and 1,142 g/d, respectively, to give total ration K concentrations that were low (LO; 12 g/kg of DM), medium (MED; 23 g/kg of DM), or high (HI; 32 g/kg of DM). Production and composition of milk was not affected by treatment. A linear effect on milk urea concentration was detected, being 4.48, 4.18, and 3.77 mM for LO, MED, and HI, respectively, and a linear tendency for rumen ammonia concentration with 6.65, 6.51, and 5.84 mg of NH₃-N/dL for LO, MED, and HI, respectively. Milk urea concentration peaked about 3h after the rumen ammonia peak from the morning feeding, at a level 1.3mM over the baseline. Urinary urea excretion declined linearly (105, 103, and 98 g of urea-N/d for LO, MED, and HI, respectively). Linear increases occurred in urinary output (0.058 ± 0.001 kg of urine/g of K intake; no intercept; coefficient of determination=0.997) and drinking water intake (65.9 ± 2.02 + 0.069 ± 0.004 kg of water/g of K intake; coefficient of determination=0.95). Urinary K concentration leveled off at 12.4 g/L. Urinary creatinine excretion was not affected by K addition, but allantoin excretion increased linearly by 27% from LO to HI, suggesting increased rumen microbial growth. Rumen pH, acetate proportion of total volatile fatty acids, and digestibility of DM, organic matter, and neutral detergent fiber increased linearly with increasing potassium intake. We concluded that increased ration K concentration lowers milk urea concentration with a magnitude significant for the interpretation of milk urea values, but other sources of variation, such as sampling time relative to feeding, may be even more important. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The effect of real and simulated time-zone shifts upon the circadian rhythms of body temperature, plasma 11-hydroxycorticosteroids, and renal excretion in human subjects

PubMed Central

Elliott, Ann L.; Mills, J. N.; Minors, D. S.; Waterhouse, J. M.

1972-01-01

1. Observations were made upon five subjects who flew through 4½-6 time zones, four of them returning later to their starting point, and upon twenty-three subjects experiencing simulated 6 or 8 hr time zones shifts in either direction in an isolation unit. 2. Measurements were made of plasma concentration of 11-hydroxycorticosteroids, of body temperature, and of urinary excretion of sodium, potassium and chloride. Their rhythm was defined, where possible, by fitting a sine curve of period 24 hr to each separate 24-hr stretch of data and computing the acrophase, or maximum predicted by the sine curve. 3. The adaptation of the plasma steroid rhythm was assessed by the presence of a sharp fall in concentration after the sample collected around 08.00 hr. The time course of adaptation varied widely between individuals; it was usually largely complete by the fourth day after westward, and rather later after eastward, flights. After time shift the pattern often corresponded neither to an adapted nor to an unadapted one, and in a subject followed for many months after a real flight a normal amplitude only appeared 2-3 months after flight. 4. Temperature rhythm adapted by a movement of the acrophase, without change in amplitude, although on some days no rhythm could be observed. This movement was always substantial even on the first day, and was usually nearly complete by the fifth. 5. High nocturnal excretion of electrolyte was often seen in the early days after time shift, more notably after simulated westward flights. Adaptation of urinary electrolyte rhythms usually proceeded as with temperature, but the movement of the acrophase was slower, more variable between individuals, more erratic, and sometimes reversed after partial adaptation. On a few days there were two maxima corresponding to those expected on real and on experimental time. 6. Sodium excretion was much less regular than that of potassium, but adapted more rapidly to time shift, so that the two often became completely dissociated. Chloride behaved much as sodium. 7. The time course of adaptation of the plasma steroid and urinary potassium rhythms were sufficiently similar to suggest a causal connexion. The time course of adaptation of the temperature rhythm did not coincide with that of any other component considered here. PMID:5016984

Alkali absorption and citrate excretion in calcium nephrolithiasis

NASA Technical Reports Server (NTRS)

Sakhaee, K.; Williams, R. H.; Oh, M. S.; Padalino, P.; Adams-Huet, B.; Whitson, P.; Pak, C. Y.

1993-01-01

The role of net gastrointestinal (GI) alkali absorption in the development of hypocitraturia was investigated. The net GI absorption of alkali was estimated from the difference between simple urinary cations (Ca, Mg, Na, and K) and anions (Cl and P). In 131 normal subjects, the 24 h urinary citrate was positively correlated with the net GI absorption of alkali (r = 0.49, p < 0.001). In 11 patients with distal renal tubular acidosis (RTA), urinary citrate excretion was subnormal relative to net GI alkali absorption, with data from most patients residing outside the 95% confidence ellipse described for normal subjects. However, the normal relationship between urinary citrate and net absorbed alkali was maintained in 11 patients with chronic diarrheal syndrome (CDS) and in 124 stone-forming patients devoid of RTA or CDS, half of whom had "idiopathic" hypocitraturia. The 18 stone-forming patients without RTA or CDS received potassium citrate (30-60 mEq/day). Both urinary citrate and net GI alkali absorption increased, yielding a significantly positive correlation (r = 0.62, p < 0.0001), with the slope indistinguishable from that of normal subjects. Thus, urinary citrate was normally dependent on the net GI absorption of alkali. This dependence was less marked in RTA, confirming the renal origin of hypocitraturia. However, the normal dependence was maintained in CDS and in idiopathic hypocitraturia, suggesting that reduced citrate excretion was largely dietary in origin as a result of low net alkali absorption (from a probable relative deficiency of vegetables and fruits or a relative excess of animal proteins).

Renal effects of continuous negative pressure breathing

NASA Technical Reports Server (NTRS)

Kinney, M. J.; Discala, V. A.

1975-01-01

Continuous negative pressure breathing (CNPB) was utilized to simulate the thoracic vascular distension of zero g or space, in 11 anesthetized rats. The animals underwent renal clearance and micropuncture renal nephron studies before, during, and after CNPB. Rats were pretreated with a high salt diet and I-M desoxycorticosterone (DOCA) in excess. None of these rats diuresed with CNPB. In contrast 5 of the 7 remaining rats increased the fraction of the filtered sodium excreted (C sub Na/GFR, p .05) and their urinary flow rate (V, p .05). Potassium excretion increased (U sub k V, p .05). End proximal tubular fluid specimen's TF/P inulin ratios were unchanged. Whole kidney and single nephron glomerular filtration rates fell 10%. CNPB, a mechanism for atrial distension, appears to cause, in rats, a decrease in distal tubular sodium, water and potassium reabsorption. Exogenous mineral-corticoid prevents the diuresis, saluresis, and kaluresis.

Analysis of Why the Renal Dialysis Unit is Losing Money

DTIC Science & Technology

1997-06-30

urinary obstruction, severe hypertension, diabetes mellitus, gout, and polycystic kidney disease. Patients with advanced chronic renal failure develop...failure. An excess amount of potassium in the body, also termed hyperkalemia , occurs in chronic renal failure because of inadequate renal excretion...Patients with hyperkalemia can develop skeletal muscle paralysis, but the most dangerous effect of hyperkalemia is the effect it has on the heart

[Risk for hyperkalemia during long-term treatment with angiotensin-converting enzyme inhibitors in insulin-dependent type 2 diabetics in relation to the glomerular filtration rate].

PubMed

Raml, A; Schmekal, B; Grafinger, P; Biesenbach, G

2001-11-23

The risk for hyperkalaemia during therapy with angiotensin-converting enzyme inhibitors is especially increased in the elderly diabetic because of a decrease in glomerular filtration rate (GFR), as well as the occurrence of hyporeninaemic hypoaldosteronism. We evaluated the risk for hyperkalaemia under long-term angiotensin-converting enyzme inhibition in 86 insulin-dependent type 2 diabetic patients in relation to their GFR. We compared the influence of a 3 to 6 months long treatment with angiotensin-converting enzyme inhibitors on the serum potassium levels, the creatinine clearance and the urinary albumin excretion in insulin-dependent type 2 diabetic patients with an initial creatinine clearance < 50 ml/min/1.73m(2) (n = 15, age 66 +/- 6 years) and >/= 50 ml/min/1.73m(2) respectively (n = 71, age 61 +/- 10 years). In addition, we also investigated the influence on the metabolic control and the blood pressure values in both groups of patients. In the patients with creatinine clearance >/= 50 ml/min/1,73m(2) the mean potassium level increased from 4.3 +/- 0.2 to 4.6 +/- 0.4 mmol/l (P < 0,01), while the incidence of a potassium level > 5 mmol/l was 17 %. In the group with a creatinine clearance < 50 ml/min/1.73m(2) the potassium level rose from 4.5 +/- 0.2 to 5.0 +/- 0.4 mmol/l (P < 0.01). The incidence of potassium levels > 5 mmol/l was 66 % (P < 0,01). In both patient groups the creatinine clearances did not change significantly during angiotensin-converting enzyme inhibition, and the urinary albumin excretion as well as the HbA(1c) values and blood pressure showed only a tendency towards a decrease. Long-term treatment with angiotensin-converting enzyme inhibitors in insulin-dependent type 2 diabetic patients leads to a significant increase in serum potassium. The incidence of hyperkalaemia with potassium levels > 5 mmol/l is significantly higher in the patients with initial creatinine clearance < 50 ml/min/1.73m(2). Severe hyperkalaemia with potassium levels > 6 mmol/l was not observed.

Significant hyperkalemia and hyponatremia secondary to telmisartan/hydrochlorothiazide treatment.

PubMed

Cakir, Mehtap

2010-12-01

The renin-angiotensin-aldosterone system (RAAS) has crucial importance in maintaining blood pressure; thus blockade of RAAS is an effective antihypertensive treatment choice. The final step in RAAS stimulation is aldosterone secretion by angiotensin II, which leads to increased renal tubular sodium absorption and potassium secretion. Angiotensin II receptor blockers (ARBs) allow blockade of RAAS by blocking binding of angiotensin II to the AT(1) receptors. There are several fixed-dose combinations of ARBs with hydrochlorothiazide in the market, providing antihypertensive therapies with complimentary mechanisms of action. With such combinations, while ARB inhibits the vasoconstricting action and aldosterone-secreting effects of angiotensin II, hydrochlorothiazide affects the renal tubular mechanisms of electrolyte reabsorption and directly increases excretion of sodium and chloride in the distal tubule, and promotes water excretion. Also, hypokalemia, which may be triggered by increased urinary potassium loss induced by hydrochlorothiazide, is opposed by ARB use and hence ARB/hydrochlorothiazide combination is known to be safe in terms of potassium imbalance. In this case report, significant hyperkalemia and hyponatremia related to telmisartan/hydrochlorothiazide use in a diabetic patient has been presented.

Difference between 24-h diet recall and urine excretion for assessing population sodium and potassium intake in adults aged 18–39 y12345

PubMed Central

Cogswell, Mary E; Valderrama, Amy L; Wang, Chia-Yih; Loria, Catherine M; Moshfegh, Alanna J; Rhodes, Donna G; Carriquiry, Alicia L

2015-01-01

Background: Limited data are available on the accuracy of 24-h dietary recalls used to monitor US sodium and potassium intakes. Objective: We examined the difference in usual sodium and potassium intakes estimated from 24-h dietary recalls and urine collections. Design: We used data from a cross-sectional study in 402 participants aged 18–39 y (∼50% African American) in the Washington, DC, metropolitan area in 2011. We estimated means and percentiles of usual intakes of daily dietary sodium (dNa) and potassium (dK) and 24-h urine excretion of sodium (uNa) and potassium (uK). We examined Spearman's correlations and differences between estimates from dietary and urine measures. Multiple linear regressions were used to evaluate the factors associated with the difference between dietary and urine measures. Results: Mean differences between diet and urine estimates were higher in men [dNa – uNa (95% CI) = 936.8 (787.1, 1086.5) mg/d and dK – uK = 571.3 (448.3, 694.3) mg/d] than in women [dNa – uNa (95% CI) = 108.3 (11.1, 205.4) mg/d and dK – uK = 163.4 (85.3, 241.5 mg/d)]. Percentile distributions of diet and urine estimates for sodium and potassium differed for men. Spearman's correlations between measures were 0.16 for men and 0.25 for women for sodium and 0.39 for men and 0.29 for women for potassium. Urinary creatinine, total caloric intake, and percentages of nutrient intake from mixed dishes were independently and consistently associated with the differences between diet and urine estimates of sodium and potassium intake. For men, body mass index was also associated. Race was associated with differences in estimates of potassium intake. Conclusions: Low correlations and differences between dietary and urinary sodium or potassium may be due to measurement error in one or both estimates. Future analyses using these methods to assess sodium and potassium intake in relation to health outcomes may consider stratifying by factors associated with the differences in estimates from these methods. This trial was registered at clinicaltrials.gov as NCT01631240. PMID:25646336

Difference between 24-h diet recall and urine excretion for assessing population sodium and potassium intake in adults aged 18-39 y.

PubMed

Mercado, Carla I; Cogswell, Mary E; Valderrama, Amy L; Wang, Chia-Yih; Loria, Catherine M; Moshfegh, Alanna J; Rhodes, Donna G; Carriquiry, Alicia L

2015-02-01

Limited data are available on the accuracy of 24-h dietary recalls used to monitor US sodium and potassium intakes. We examined the difference in usual sodium and potassium intakes estimated from 24-h dietary recalls and urine collections. We used data from a cross-sectional study in 402 participants aged 18-39 y (∼50% African American) in the Washington, DC, metropolitan area in 2011. We estimated means and percentiles of usual intakes of daily dietary sodium (dNa) and potassium (dK) and 24-h urine excretion of sodium (uNa) and potassium (uK). We examined Spearman's correlations and differences between estimates from dietary and urine measures. Multiple linear regressions were used to evaluate the factors associated with the difference between dietary and urine measures. Mean differences between diet and urine estimates were higher in men [dNa - uNa (95% CI) = 936.8 (787.1, 1086.5) mg/d and dK - uK = 571.3 (448.3, 694.3) mg/d] than in women [dNa - uNa (95% CI) = 108.3 (11.1, 205.4) mg/d and dK - uK = 163.4 (85.3, 241.5 mg/d)]. Percentile distributions of diet and urine estimates for sodium and potassium differed for men. Spearman's correlations between measures were 0.16 for men and 0.25 for women for sodium and 0.39 for men and 0.29 for women for potassium. Urinary creatinine, total caloric intake, and percentages of nutrient intake from mixed dishes were independently and consistently associated with the differences between diet and urine estimates of sodium and potassium intake. For men, body mass index was also associated. Race was associated with differences in estimates of potassium intake. Low correlations and differences between dietary and urinary sodium or potassium may be due to measurement error in one or both estimates. Future analyses using these methods to assess sodium and potassium intake in relation to health outcomes may consider stratifying by factors associated with the differences in estimates from these methods. This trial was registered at clinicaltrials.gov as NCT01631240. © 2015 American Society for Nutrition.

Evaluation of the Children's Eating Habits Questionnaire used in the IDEFICS study by relating urinary calcium and potassium to milk consumption frequencies among European children.

PubMed

Huybrechts, I; Börnhorst, C; Pala, V; Moreno, L A; Barba, G; Lissner, L; Fraterman, A; Veidebaum, T; Hebestreit, A; Sieri, S; Ottevaere, C; Tornaritis, M; Molnár, D; Ahrens, W; De Henauw, S

2011-04-01

Measuring dietary intake in children is notoriously difficult. Therefore, it is crucial to evaluate the performance of dietary intake assessment methods in children. Given the important contribution of milk consumption to calcium (Ca) and potassium (K) intakes, urinary calcium (UCa) and potassium (UK) excretions in spot urine samples could be used for estimating correlations with milk consumption frequencies. The aim of this study was to evaluate the assessment of milk consumption frequencies derived from the Food Frequency Questionnaire section of the Children's Eating Habits Questionnaire (CEHQ-FFQ) used in the IDEFICS (Identification and prevention of dietary- and lifestyle induced health effects in children and infants) study by comparing with UCa and UK excretions in spot urine samples. This study was conducted as a setting-based community-oriented intervention study and results from the first cross-sectional survey have been included in the analysis. A total of 10,309 children aged 2-10 years from eight European countries are included in this analysis. UCa and UK excretions were measured in morning spot urine samples. Calcium and potassium urine concentrations were standardised for urinary creatinine (Cr) excretion. Ratios of UCa/Cr and UK/Cr were used for multivariate regression analyses after logarithmic transformation to obtain normal distributions of data. Milk consumption frequencies were obtained from the CEHQ-FFQ. Multivariate regression analyses were used to investigate the effect of milk consumption frequencies on UCa and UK concentrations, adjusting for age, gender, study centre, soft drink consumption and frequency of main meals consumed at home. A significant positive correlation was found between milk consumption frequencies and ratios of UK/Cr and a weaker but still significant positive correlation with ratios of UCa/Cr, when using crude or partial Spearman's correlations. Multivariate regression analyses showed that milk consumption frequencies were predictive of UCa/Cr and UK/Cr ratios, when adjusted for age, gender, study centre, soft drink consumption and frequency of main meals consumed at home. Mean ratios of UK/Cr for increasing milk consumption frequency tertiles showed a progressive increase in UK/Cr. Children consuming at least two milk servings per day had significantly higher mean UCa/Cr and UK/Cr ratios than children who did not. Large differences in correlations between milk consumption frequencies and ratios of UCa/Cr and UK/Cr were found between the different study centres. Higher milk consumption frequencies resulted in a progressive increase in UK/Cr and UCa/Cr ratios, reflecting the higher Ca and K intakes that coincide with increasing milk consumption, which constitutes a major K and Ca source in children's diet.

Effect of indapamide on urinary calcium excretion in patients with and without urinary stone disease.

PubMed

Ceylan, Kadir; Topal, Cevat; Erkoc, Reha; Sayarlioglu, Hayriye; Can, Saban; Yilmaz, Yuksel; Dogan, Ekrem; Algun, Ekrem; Gonulalan, Hasan

2005-06-01

Indapamide is an antihypertensive agent similar to thiazides, but with some different effects. Thiazide and thiazide-like diuretics are useful in preventing recurrent urinary stone formation due to their hypocalciuric effects. To determine the hypocalciuric and other effects on certain laboratory parameters of indapamide 1.5 mg in different patient groups. Four groups of patients recruited from urology and nephrology outpatient departments were experiencing non-hypercalciuric urinary stone disease (group 1), idiopathic hypercalciuria (group 2), urinary stone disease with hypercalciuria (group 3), and essential hypertension (group 4). In all patients, fasting serum uric acid, calcium, sodium, potassium, cholesterol, triglyceride, parathyroid hormone (PTH) values, and morning second-spot urine calcium and creatinine levels were assessed before and 8 weeks after treatment with indapamide. Urinary calcium excretion was reduced significantly in all groups: group 1 from 0.10 +/- 0.02 to 0.07 +/- 0.03 (mean +/-SD; 30% reduction; p < 0.001), group 2 from 0.30 +/- 0.15 to 0.15 +/- 0.10 (50% reduction; p < 0.001), group 3 from 0.35 +/- 0.15 to 0.20 +/- 0.10 (43% reduction; p < 0.001), and group 4 from 0.10 +/- 0.03 to 0.08 +/- 0.02 (20% reduction; p < 0.0010). These results should be interpreted with caution since no control group was included in this study. Mean serum uric acid and triglyceride levels were significantly increased, and mean PTH and potassium levels and diastolic and systolic blood pressure were significantly decreased in all groups. Few temporary adverse effects, such as dizziness and fatigue, were noticed and none of them caused discontinuation of treatment. Indapamide 1.5 mg/day is effective in decreasing calciuria in patients with non-hypercalciuric urinary stone disease, idiopathic hypercalciuria, urinary stone disease with hypercalciuria, and essential hypertension. This could be achieved with few adverse effects similar to those of thiazides and indapamide 2.5 mg. Indapamide decreased the PTH levels in all groups. Long-term clinical benefits of these effects should be evaluated prospectively with further randomized studies.

Optimum nutrition for kidney stone disease.

PubMed

Heilberg, Ita P; Goldfarb, David S

2013-03-01

We summarize the data regarding the associations of individual dietary components with kidney stones and the effects on 24-hour urinary profiles. The therapeutic recommendations for stone prevention that result from these studies are applied where possible to stones of specific composition. Idiopathic calcium oxalate stone-formers are advised to reduce ingestion of animal protein, oxalate, and sodium while maintaining intake of 800 to 1200 mg of calcium and increasing consumption of citrate and potassium. There are few data regarding dietary therapy of calcium phosphate stones. Whether the inhibitory effect of citrate sufficiently counteracts increasing urine pH to justify more intake of potassium and citrate is not clear. Reduction of sodium intake to decrease urinary calcium excretion would also be expected to decrease calcium phosphate stone recurrence. Conversely, the most important urine variable in the causation of uric acid stones is low urine pH, linked to insulin resistance as a component of obesity and the metabolic syndrome. The mainstay of therapy is weight loss and urinary alkalinization provided by a more vegetarian diet. Reduction in animal protein intake will reduce purine ingestion and uric acid excretion. For cystine stones, restriction of animal protein is associated with reduction in intake of the cystine precursor methionine as well as cystine. Reduction of urine sodium results in less urine cystine. Ingestion of vegetables high in organic anion content, such as citrate and malate, should be associated with higher urine pH and fewer stones because the amino acid cystine is soluble in more alkaline urine. Because of their infectious origin, diet has no definitive role for struvite stones except for avoiding urinary alkalinization, which may worsen their development. Published by Elsevier Inc.

Dietary treatment of urinary risk factors for renal stone formation. A review of CLU Working Group.

PubMed

Prezioso, Domenico; Strazzullo, Pasquale; Lotti, Tullio; Bianchi, Giampaolo; Borghi, Loris; Caione, Paolo; Carini, Marco; Caudarella, Renata; Ferraro, Manuel; Gambaro, Giovanni; Gelosa, Marco; Guttilla, Andrea; Illiano, Ester; Martino, Marangella; Meschi, Tiziana; Messa, Piergiorgio; Miano, Roberto; Napodano, Giorgio; Nouvenne, Antonio; Rendina, Domenico; Rocco, Francesco; Rosa, Marco; Sanseverino, Roberto; Salerno, Annamaria; Spatafora, Sebastiano; Tasca, Andrea; Ticinesi, Andrea; Travaglini, Fabrizio; Trinchieri, Alberto; Vespasiani, Giuseppe; Zattoni, Filiberto

2015-07-07

Diet interventions may reduce the risk of urinary stone formation and its recurrence, but there is no conclusive consensus in the literature regarding the effectiveness of dietary interventions and recommendations about specific diets for patients with urinary calculi. The aim of this study was to review the studies reporting the effects of different dietary interventions for the modification of urinary risk factors in patients with urinary stone disease. A systematic search of the Pubmed database literature up to July 1, 2014 for studies on dietary treatment of urinary risk factors for urinary stone formation was conducted according to a methodology developed a priori. Studies were screened by titles and abstracts for eligibility. Data were extracted using a standardized form and the quality of evidence was assessed. Evidence from the selected studies were used to form evidence-based guideline statements. In the absence of sufficient evidence, additional statements were developed as expert opinions. General measures: Each patient with nephrolithiasis should undertake appropriate evaluation according to the knowledge of the calculus composition. Regardless of the underlying cause of the stone disease, a mainstay of conservative management is the forced increase in fluid intake to achieve a daily urine output of 2 liters. HYPERCALCIURIA: Dietary calcium restriction is not recommended for stone formers with nephrolithiasis. Diets with a calcium content ≥ 1 g/day (and low protein-low sodium) could be protective against the risk of stone formation in hypercalciuric stone forming adults. Moderate dietary salt restriction is useful in limiting urinary calcium excretion and thus may be helpful for primary and secondary prevention of nephrolithiasis. A low-normal protein intake decrease calciuria and could be useful in stone prevention and preservation of bone mass. Omega-3 fatty acids and bran of different origin decreases calciuria, but their impact on the urinary stone risk profile is uncertain. Sports beverage do not affect the urinary stone risk profile. HYPEROXALURIA: A diet low in oxalate and/or a calcium intake normal to high (800-1200 mg/day for adults) reduce the urinary excretion of oxalate, conversely a diet rich in oxalates and/or a diet low in calcium increase urinary oxalate. A restriction in protein intake may reduce the urinary excretion of oxalate although a vegetarian diet may lead to an increase in urinary oxalate. Adding bran to a diet low in oxalate cancels its effect of reducing urinary oxalate. Conversely, the addition of supplements of fruit and vegetables to a mixed diet does not involve an increased excretion of oxalate in the urine. The intake of pyridoxine reduces the excretion of oxalate. HYPERURICOSURIA: In patients with renal calcium stones the decrease of the urinary excretion of uric acid after restriction of dietary protein and purine is suggested although not clearly demonstrated. HYPOCITRATURIA: The administration of alkaline-citrates salts is recommended for the medical treatment of renal stone-formers with hypocitraturia, although compliance to this treatment is limited by gastrointestinal side effects and costs. Increased intake of fruit and vegetables (excluding those with high oxalate content) increases citrate excretion and involves a significant protection against the risk of stone formation. Citrus (lemons, oranges, grapefruit, and lime) and non citrus fruits (melon) are natural sources of dietary citrate, and several studies have shown the potential of these fruits and/or their juices in raising urine citrate levels. There are enought basis to advice an adequate fluid intake also in children. Moderate dietary salt restriction and implementation of potassium intake are useful in limiting urinary calcium excretion whereas dietary calcium restriction is not recommended for children with nephrolithiasis. It seems reasonable to advice a balanced consumption of fruit and vegetables and a low consumption of chocolate and cola according to general nutritional guidelines, although no studies have assessed in pediatric stone formers the effect of fruit and vegetables supplementation on urinary citrate and the effects of chocolate and cola restriction on urinary oxalate in pediatric stone formers. Despite the low level of scientific evidence, a low-protein (< 20 g/day) low-salt (< 2 g/day) diet with high hydration (> 3 liters/day) is strongly advised in children with cystinuria. ELDERLY: In older patients dietary counseling for renal stone prevention has to consider some particular aspects of aging. A restriction of sodium intake in association with a higher intake of potassium, magnesium and citrate is advisable in order to reduce urinary risk factors for stone formation but also to prevent the loss of bone mass and the incidence of hypertension, although more hemodynamic sensitivity to sodium intake and decreased renal function of the elderly have to be considered. A diet rich in calcium (1200 mg/day) is useful to maintain skeletal wellness and to prevent kidney stones although an higher supplementation could involve an increase of risk for both the formation of kidney stones and cardiovascular diseases. A lower content of animal protein in association to an higher intake of plant products decrease the acid load and the excretion of uric acid has no particular contraindications in the elderly patients, although overall nutritional status has to be preserved.

Plasma potassium and diurnal cyclic potassium excretion in the rat.

PubMed

Rabinowitz, L; Berlin, R; Yamauchi, H

1987-12-01

The relation of the plasma potassium concentration to the daily cyclic variation in potassium excretion was examined in undisturbed, unanesthetized male Sprague-Dawley rats maintained on a liquid diet in a 12-h light-dark environment. Potassium excretion increased from a light-phase minimum of 16 mu eq/h to a peak of 256 mu eq/h 3 h after the beginning of the dark phase. Plasma potassium concentration in arterial blood, sampled in rats at 90-min intervals during these changes in potassium excretion, showed no significant change and was in the range 4.50-4.99 meq/liter. In adrenalectomized rats receiving aldosterone and dexamethasone at constant basal rates by implanted pumps, the daily cycle of potassium excretion was the same as in the intact rats, and plasma potassium was not significantly different when measured at the time of minimum and maximum rates of potassium excretion (4.79 +/- 0.42 vs 5.16 +/- 0.47 meq/liter, mean +/- SD). These results indicate that plasma potassium concentration is not the efferent factor controlling diurnal cyclic changes in potassium excretion in adrenal intact rats and may not be the only significant factor in adrenalectomized-steroid replaced rats.

Neonatal handling reduces renal function in adult rats.

PubMed

Donadio, Márcio Vinícius Fagundes; Jacobs, Silvana; Corezola, Kizzy Ludnila; Melo, Denizar Alberto da Silva; Dias, Henrique Bregolin; Reichel, Carlos Luiz; Franci, Celso Rodrigues; Jeckel-Neto, Emilio Antonio; Lulhier, Francisco; Lucion, Aldo Bolten; de Oliveira, Jarbas Rodrigues; Sanvitto, Gilberto Luiz

2009-01-01

To evaluate the effects of neonatal handling on hydroelectrolytic balance in adult rats. The litters were divided into two groups: nonhandled and handled. The procedure consisted of handling the pups for 1 min/day in the first 10 days postnatally. When adults, animals had their body weight verified and were housed in individual metabolic cages. After a 24-hour period, urine samples were collected and the urinary and water intake volumes measured. Blood samples to determine osmolality, aldosterone, corticosterone, angiotensin II, creatinine, urea, sodium and potassium levels were collected. The kidneys were removed for histological assessment. Urinary osmolality, sodium, urea and creatinine were also measured and the creatinine clearance (CC) calculated. No difference between groups was found in the body weight. Handled animals showed a reduction in the total kidney wet weight, water intake, urinary volume, CC, plasma angiotensin II, corticosterone and aldosterone when compared to the nonhandled and an increase in the urinary osmolality and sodium excretion fraction. No differences in serum potassium and no evidence of structural changes were demonstrated by histological analysis. Neonatal handling induced long-lasting effects decreasing renal function without evidence of kidney structural changes. (c) 2009 S. Karger AG, Basel.

The Spectrum of Subclinical Primary Aldosteronism and Incident Hypertension: A Cohort Study

PubMed Central

Brown, Jenifer M.; Robinson-Cohen, Cassianne; Fernandez, Miguel Angel Luque; Allison, Matthew A.; Baudrand, Rene; Ix, Joachim H.; Kestenbaum, Bryan; de Boer, Ian H.; Vaidya, Anand

2018-01-01

Background Primary aldosteronism is recognized as a severe form of “renin-independent aldosteronism” that results in excessive mineralocorticoid receptor (MR) activation. Objective To investigate whether there is a spectrum of subclinical renin-independent aldosteronism among normotensives that increases risk for hypertension. Design Cohort study. Setting National community-based study. Participants 850 untreated normotensive participants in the Multi-Ethnic Study of Atherosclerosis with measurements of serum aldosterone, plasma renin activity (PRA). Measurements Longitudinal analyses investigated whether aldosterone concentrations, in the context of physiologic PRA phenotypes (suppressed: ≤0.50; indeterminate: 0.51–0.99; unsuppressed: ≥1.0 μg/L/h), associated with incident hypertension, defined as SBP≥140, DBP≥90 mmHg, or initiation of anti-hypertensive medications. Cross-sectional analyses investigated associations of aldosterone with MR activity, assessed via serum potassium and urinary fractional excretion of potassium. Results A suppressed renin phenotype was associated with a higher rate of incident hypertension when compared to other PRA phenotypes (85.4 [73.4, 99.3] vs. 53.3 [42.8, 66.4] vs. 54.5 [41.8, 71.0] cases per 1000 person-years of follow-up). With renin suppression, higher aldosterone concentrations were independently associated with an increased risk for incident hypertension; whereas no association between aldosterone and hypertension was observed when renin was not suppressed. Higher aldosterone concentrations were associated with lower serum potassium and higher urinary excretion of potassium, but only when renin was suppressed. Limitations Measurements of sodium and potassium occurred several years before renin and aldosterone. Conclusions Suppression of renin, and higher aldosterone concentrations in the context of this renin suppression, associated with an increased risk for developing hypertension and possibly also with increased MR activity. These findings suggest a clinically-relevant spectrum of subclinical primary aldosteronism (renin-independent aldosteronism) in normotension. Funding National Institutes of Health PMID:29052707

Use of Potassium Citrate to Reduce the Risk of Renal Stone Formation During Spaceflight

NASA Technical Reports Server (NTRS)

Whitson, P. A.; Pietrzyk, R. A.; Sams, C. F.; Jones, J. A.; Nelman-Gonzalez, M.; Hudson, E. K.

2008-01-01

Introduction: NASA s Vision for Space Exploration centers on exploration class missions including the goals of returning to the moon and landing on Mars. One of NASA s objectives is to focus research on astronaut health and the development of countermeasures that will protect crewmembers during long duration voyages. Exposure to microgravity affects human physiology and results in changes in the urinary chemical composition favoring urinary supersaturation and an increased risk of stone formation. Nephrolithiasis is a multifactorial disease and development of a renal stone is significantly influenced by both dietary and environmental factors. Previous results from long duration Mir and short duration Shuttle missions have shown decreased urine volume, pH, and citrate levels and increased calcium. Citrate, an important inhibitor of calcium-containing stones, binds with urinary calcium reducing the amount of calcium available to form stones. Citrate inhibits renal stone recurrence by preventing crystal growth, aggregation, and nucleation and is one of the most common therapeutic agents used to prevent stone formation. Methods: Thirty long duration crewmembers (29 male, 1 female) participated in this study. 24-hour urines were collected and dietary monitoring was performed pre, in, and postflight. Crewmembers in the treatment group received two potassium citrate (KCIT) pills, 10 mEq/pill, ingested daily beginning 3 days before launch, all inflight days and through 14 days postflight. Urinary biochemical and dietary analyses were completed. Results: KCIT treated subjects exhibited decreased urinary calcium excretion and maintained the levels of calcium oxalate supersaturation risk at their preflight levels. The increased urinary pH levels in these subjects reduced the risk of uric acid stones. Discussion: The current study investigated the use of potassium citrate as a countermeasure to minimize the risk of stone formation during ISS missions. Results suggest that supplementation with potassium citrate decreases the risk of stone formation during and immediately after spaceflight.

The circadian rhythms of human subjects without timepieces or indication of the alternation of day and night

PubMed Central

Mills, J. N.; Minors, D. S.; Waterhouse, J. M.

1974-01-01

1. Seven solitary subjects, and two groups of four, spent from 5 to 13 days in an isolation unit without knowledge of time. Three solitary subjects and one group of four adopted fairly regular activity habits with a period of 25-27 h; one subject adopted a period of 30 h, and one of 27 h initially, decreasing to 24-25 h after a few days. One group of four awoke roughly every 24 h, after a sleep which was alternately about 8 h, or about 4 h and believed by the subjects to be an afternoon siesta. Two solitary subjects alternated sleeps of about 8 or 16 h, separated by 24 h of activity. 2. Deep temperature in all subjects oscillated with a period of 24-26 h, which was thus commonly distinct from their activity habits. 3. Urinary potassium followed a rhythm whose period, though usually close to, was sometimes distinct from, that of temperature. A secondary period corresponding to that of activity was also sometimes present. 4. Urinary sodium and chloride usually gave evidence of two periodic components, one corresponding to activity and the other to the rhythm of either temperature or of urinary potassium. 5. Urinary creatinine and phosphate usually followed the subject's routine of activity. 6. Plasma samples were collected on a few occasions and analysed for phosphate and 11-hydroxycorticosteroids. Changes in plasma phosphate were usually, but not always, associated with similar changes in urinary phosphate, and changes in plasma corticosteroids were often, but not always, associated with similar changes in urinary potassium shortly afterwards. 7. Observations are recorded on a subject alone in a cave for 127 days. His activity habits, though wildly variable, gave evidence of a period of 25·1 h and his urinary electrolyte excretion indicated a shorter period, of 24·6 h. During the following 3 days, when he remained in the cave but was visited frequently, his plasma corticosteroids and urinary potassium oscillated with a period of 16 h. 8. The possible mechanisms controlling these rhythms are discussed. PMID:4416124

Urinary Sodium Excretion and Dietary Sources of Sodium Intake in Chinese Postmenopausal Women with Prehypertension

PubMed Central

Liu, Zhao-min; Ho, Suzanne C.; Tang, Nelson; Chan, Ruth; Chen, Yu-ming; Woo, Jean

2014-01-01

Background Reducing salt intake in communities is one of the most effective and affordable public health strategies to prevent hypertension, stroke and renal disease. The present study aimed to determine the sodium intake in Hong Kong Chinese postmenopausal women and identify the major food sources contributing to sodium intake and urine excretion. Methods This was a cross-sectional study among 655 Chinese postmenopausal women with prehypertension who were screened for a randomized controlled trial. Data collection included 24 h urine collection for the measurement of sodium, potassium and creatinine, 3-day dietary records, anthropometric measures and questionnaire survey on demographic data and dietary habits. Results The average salt intake estimated from urinary excretion was 7.8±3.2 g/d with 82.1% women above WHO recommendation of 5 g/day. Food groups as soup (21.6%), rice and noodles (13.5%), baked cereals (12.3%), salted/preserved foods (10.8%), Chinese dim sum (10.2%) and sea foods (10.1%) were the major contributors of non-discretionary salt. Discretionary salt use in cooking made a modest contribution to overall intake. Vegetable and fruit intake, age, sodium intake from salted foods, sea foods and soup were the independent determinants of urinary sodium excretion. Conclusions Our data revealed a significant room for reduction of the sodium intake. Efforts to reduce sodium from diets in Hong Kong Chinese postmenopausal women should focus on both processed foods and discretionary salt during cooking. Sodium reduction in soup and increase in fruit intake would be potentially effective strategy for reducing sodium. PMID:25083775

Creatinine, urea, uric acid, water and electrolytes renal handling in the healthy oldest old

PubMed Central

Musso, Carlos Guido; Álvarez Gregori, Joaquín; Jauregui, José Ricardo; Macías Núñez, Juan Florencio

2012-01-01

Renal physiology in the healthy oldest old has the following characteristics, in comparison with the renal physiology in the young: a reduced creatinine clearance, tubular pattern of creatinine back-filtration, preserved proximal tubule sodium reabsorption and uric acid secretion, reduced sodium reabsorption in the thick ascending loop of Henle, reduced free water clearance, increased urea excretion, presence of medulla hypotonicity, reduced urinary dilution and concentration capabilities, and finally a reduced collecting tubules response to furosemide which expresses a reduced potassium excretion in this segment due to a sort of aldosterone resistance. All physiological changes of the aged kidney are the same in both genders. PMID:24175249

Variability of urinary salt excretion estimated by spot urine in treated hypertensive patients.

PubMed

Arakawa, Kimika; Sakaki, Minako; Sakata, Satoko; Oniki, Hideyuki; Tominaga, Mitsuhiro; Tsuchihashi, Takuya

2015-01-01

Among the several methods used to assess salt intake, estimating 24 h urinary salt excretion by spot urine seems appropriate for clinical practice. In this study, we investigated variability in urinary salt excretion using spot urine in hypertensive outpatients. Participants included 200 hypertensive patients who underwent spot urinary salt excretion at least three times during the observation period. Mean urinary salt excretion and the coefficient of the variation were 8.62 ± 1.96 g/day and 19.0 ± 10.2%, respectively. In the analysis of participants who underwent assessment of urinary salt excretion at least eight times (n = 54), a significant reduction in mean urinary salt excretion was found at the 5th measurement. On the contrary, the coefficient of the variation of urinary salt excretion continued to increase until the 5th measurement, and became stable thereafter. Mean urinary salt excretion was positively correlated with mean clinic diastolic blood pressure (r = 0.27, p < 0.05). Clinic diastolic blood pressure in the high urinary salt excretion group (≥ 10 g/day) was significantly higher than that of the low group (76.2 ± 7.5 vs 73.4 ± 8.3 mmHg, p < 0.05). Mean urinary salt excretion in summer was significantly lower than that of the other seasons (7.75 ± 1.94 vs 9.09 ± 2.68 (spring), 8.72 ± 2.12 (autumn), 8.92 ± 2.17 (winter) g/day, p < 0.01). In conclusion, repeated measurements of urinary salt excretion using spot urine are required to assess daily salt intake of hypertensive patients.

Relationship between sodium and potassium intake and blood pressure in a sample of overweight adults.

PubMed

Ndanuko, Rhoda N; Tapsell, Linda C; Charlton, Karen E; Neale, Elizabeth P; O'Donnell, Katrina M; Batterham, Marijka J

2017-01-01

The aim of this study was to examine the relationship between sodium and potassium intakes and blood pressure (BP) in a clinical sample. Secondary analysis of baseline data from 328 participants (mean age: 43.6 ± 8 y, mean body mass index [BMI]: 32.4 ± 4.2 kg/m 2 , mean systolic BP [SBP]/diastolic BP [DBP]: 124.9 ± 14.5/73.3 ± 9.9 mm Hg) of the 12-mo HealthTrack randomized controlled weight loss trial was conducted. Resting BP and 24-h urine sodium and potassium were measured. Dietary intake was evaluated with 4-d food records and self-reported diet histories. Urinary sodium was positively correlated (Spearman's rho) with SBP (r = 0.176; P = 0.001) and DBP (r = 0.150; P = 0.003). The ratio of sodium to potassium was positively correlated with SBP (r = 0.1; P = 0.035). Urinary sodium (F [4,323] = 20.381; P < 0.0005; adjusted R 2  = 0.231) and sodium-to-potassium ratio (F[4,323] = 25.008; P < 0.0005; adjusted R 2  = 0.227) significantly predicted SBP after controlling for age, sex, BMI, and hypertension medication use. Dietary sodium and potassium significantly predicted urinary sodium (B = 0.33, t = 4.032, P < 0.01) and potassium (B = 0.67, t = 8.537, P < 0.01) excretion, respectively, after adjustment for energy and BMI. Median dietary sodium intake was 3197 mg/d and median dietary potassium intake was 2886 mg/d. Cereal-based products and dishes were the major contributors (22%) to total sodium intake. In the present study, a high dietary sodium intake and high sodium-to-potassium ratio predicted high SBP. This suggests a need to focus dietary advice on reduction of sources of sodium and increasing sources of potassium in weight loss interventions to improve BP control. Copyright © 2016 Elsevier Inc. All rights reserved.

Early effects of synthetic bovine parathyroid hormone and synthetic salmon calcitonin on urinary excretion of cyclic AMP, phosphate and calcium in man.

PubMed

Caniggia, A; Gennari, C; Vattimo, A; Nardi, P; Nuti, R; Galli, M

1976-04-20

Bovine synthetic parathyroid hormone infused intravenously in man increased both the urinary excretion of cyclic AMP and the urinary excretion of phosphate whereas a Salmon synthetic calcitonin infusion increased the urinary excretion of phosphate without change in urinary excretion of cyclic AMP. These data are consistent with the hypothesis that different renal mechanisms are involved in the response to each hormone.

Case report: a rare cause of metabolic alkalosis

PubMed Central

Gebara, Otávio C.E.; Callas, Silvia H.V.; Hoff, Ana O.; Hoff, Paulo M.; Galvão, P.C.A.

2011-01-01

A case of a 66-year-old white man with recent onset of oedema, hypertension, metabolic alkalosis and profound hypokalaemia is described. The initial laboratorial workup showed that urinary chloride concentration and potassium excretion were increased, suggesting a state of hyperaldosteronism. Nonetheless, renin activity was low and aldosterone levels were normal. The metabolic alkalosis seen in this case was due to a rare cause, the ectopic adrenocorticotropic hormone syndrome. A literature review in the subject is presented. PMID:25984146

A physiologic-based approach to the evaluation of a patient with hyperkalemia.

PubMed

Palmer, Biff F

2010-08-01

Hyperkalemia generally is attributable to cell shifts or abnormal renal potassium excretion. Cell shifts account for transient increases in serum potassium levels, whereas sustained hyperkalemia generally is caused by decreased renal potassium excretion. Impaired renal potassium excretion can be caused by a primary decrease in distal sodium delivery, a primary decrease in mineralocorticoid level or activity, or abnormal cortical collecting duct function. Excessive potassium intake is an infrequent cause of hyperkalemia by itself, but can worsen the severity of hyperkalemia when renal excretion is impaired. Before concluding that a cell shift or renal defect in potassium excretion is present, pseudohyperkalemia should be excluded. Copyright (c) 2010 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Increased Intake of Selected Vegetables, Herbs and Fruit may Reduce Bone Turnover in Post-Menopausal Women

PubMed Central

Gunn, Caroline Ann; Weber, Janet Louise; McGill, Anne-Thea; Kruger, Marlena Cathorina

2015-01-01

Increased consumption of vegetables/herbs/fruit may reduce bone turnover and urinary calcium loss in post-menopausal women because of increased intake of polyphenols and potassium, but comparative human studies are lacking. The main aim was to compare bone turnover markers and urinary calcium excretion in two randomised groups (n = 50) of healthy post-menopausal women consuming ≥9 servings of different vegetables/herbs/fruit combinations (three months). Group A emphasised a generic range of vegetables/herbs/fruit, whereas Group B emphasised specific vegetables/herbs/fruit with bone resorption-inhibiting properties (Scarborough Fair Diet), with both diets controlled for potential renal acid load (PRAL). Group C consumed their usual diet. Plasma bone markers, urinary electrolytes (24 h) and estimated dietary PRAL were assessed at baseline and 12 weeks. Procollagen type I N propeptide (PINP) decreased (−3.2 μg/L, p < 0.01) in the B group only, as did C-terminal telopeptide of type I collagen (CTX) (−0.065 μg/L, p < 0.01) in women with osteopenia compared to those with normal bone mineral density (BMD) within this group. Intervention Groups A and B had decreased PRAL, increased urine pH and significantly decreased urinary calcium loss. Urinary potassium increased in all groups, reflecting a dietary change. In conclusion, Group B demonstrated positive changes in both turnover markers and calcium conservation. PMID:25856221

The Effect of Salt Intake and Potassium Supplementation on Serum Gastrin Levels in Chinese Adults: A Randomized Trial

PubMed Central

Wang, Yuan-Yuan; He, Wen-Wen; Liu, Yan-Chun; Lin, Yi-Feng; Hong, Lu-Fei

2017-01-01

Excess dietary salt is strongly correlated with cardiovascular disease, morbidity, and mortality. Conversely, potassium likely elicits favorable effects against cardiovascular disorders. Gastrin, which is produced by the G-cells of the stomach and duodenum, can increase renal sodium excretion and regulate blood pressure by acting on the cholecystokinin B receptor. The aim of our study was to assess the effects of altered salt and potassium supplementation on serum gastrin levels in humans. A total of 44 subjects (38–65 years old) were selected from a rural community in northern China. All subjects were sequentially maintained on a relatively low-salt diet for 7 days (3.0 g/day of NaCl), a high-salt diet for 7 days (18.0 g/day of NaCl), and then a high-salt diet supplemented with potassium for another 7 days (18.0 g/day of NaCl + 4.5 g/day of KCl). The high-salt intake significantly increased serum gastrin levels (15.3 ± 0.3 vs. 17.6 ± 0.3 pmol/L). This phenomenon was alleviated through potassium supplementation (17.6 ± 0.3 vs. 16.5 ± 0.4 pmol/L). Further analyses revealed that serum gastrin was positively correlated with 24 h urinary sodium excretion (r = 0.476, p < 0.001). By contrast, gastrin level was negatively correlated with blood pressure in all dietary interventions (r = −0.188, p = 0.031). The present study indicated that variations in dietary salt and potassium supplementation affected the serum gastrin concentrations in the Chinese subjects. PMID:28420122

Calciuric effects of protein and potassium bicarbonate but not of sodium chloride or phosphate can be detected acutely in adult women and men.

PubMed

Whiting, S J; Anderson, D J; Weeks, S J

1997-05-01

An acute load test was used to test the influence of dietary factors on urinary calcium excretion. In study 1, 10 fasting premenopausal women consumed test meals providing a moderate amount of protein (MP; 23 g), MP plus 23 mmol KHCO3 (MP+K), MP plus 23 mmol NaCl (MP+Na), and a high amount of protein (HP; 53 g), HP plus 70 mmol KHCO3 (HP+K), and HP plus 70 mmol NaCl (HP+Na). Protein was casein:lactalbumin (80:20), except for the treatments with added sodium chloride, to which only casein was added. In study 2, the effects of HP and HP plus 50 mmol KHCO3 (HP+K) were compared with those of MP or MP plus 7.5 mmol phosphate (MP+Pi), equaling the additional phosphate of HP, in 10 adult men. Subjects completed all treatments in random order. In study 1, the peak of calcium excretion was at 3 h for all treatments, except for HP+K, which indicated an acute hypocalciuric effect of potassium. Unexpectedly, there was no hypercalciuric effect of adding sodium chloride, nor was urine sodium increased. In study 2, calcium excretion was significantly higher with HP than with MP+Pi but not with MP at 3 h, indicating an acute hypercalciuric effect of protein alone. A hypocalciuric effect of potassium (HP+K compared with HP) but not of phosphate (MP compared with MP+Pi) was seen. An acute load test measuring changes 3 h postload was appropriate for examining the calciuric effects of protein and potassium bicarbonate, but not those of sodium chloride or phosphate in adults.

Urinary Angiotensinogen and Renin Excretion are Associated with Chronic Kidney Disease.

PubMed

Juretzko, Annett; Steinbach, Antje; Hannemann, Anke; Endlich, Karlhans; Endlich, Nicole; Friedrich, Nele; Lendeckel, Uwe; Stracke, Sylvia; Rettig, Rainer

2017-01-01

Several studies sought to identify new biomarkers for chronic kidney disease (CKD). As the renal renin-angiotensin system is activated in CKD, urinary angiotensinogen or renin excretion may be suitable candidates. We tested whether urinary angiotensinogen or renin excretion is elevated in CKD and whether these parameters are associated with estimated glomerular filtration rate (eGFR). We further tested whether urinary angiotensinogen or renin excretion may convey additional information beyond that provided by albuminuria. We measured urinary and plasma angiotensinogen, renin, albumin and creatinine in 177 CKD patients from the Greifswald Approach to Individualized Medicine project and in 283 healthy controls from the Study of Health in Pomerania. The urinary excretion of specific proteins is given as protein-to-creatinine ratio. Receiver operating characteristic (ROC) curves, spearman correlation coefficients and linear regression models were calculated. Urinary angiotensinogen [2,511 (196-31,909) vs. 18.6 (8.3-44.0) pmol/g, *P<0.01] and renin excretion [0.311 (0.135-1.155) vs. 0.069 (0.045-0.148) pmol/g, *P<0.01] were significantly higher in CKD patients than in healthy controls. The area under the ROC curve was significantly larger when urinary angiotensinogen, renin and albumin excretion were combined than with urinary albumin excretion alone. Urinary angiotensinogen (ß-coefficient -2.405, standard error 0.117, P<0.01) and renin excretion (ß-coefficient -0.793, standard error 0.061, P<0.01) were inversely associated with eGFR. Adjustment for albuminuria, age, sex, systolic blood pressure and body mass index did not significantly affect the results. Urinary angiotensinogen and renin excretion are elevated in CKD patients. Both parameters are negatively associated with eGFR and these associations are independent of urinary albumin excretion. In CKD patients urinary angiotensinogen and renin excretion may convey additional information beyond that provided by albuminuria. © 2017 The Author(s)Published by S. Karger AG, Basel.

Urinary Acid Excretion Can Predict Changes in Bone Metabolism During Space Flight

NASA Technical Reports Server (NTRS)

Zwart, Sara R.; Smith, Scott M.

2011-01-01

Mitigating space flight-induced bone loss is critical for space exploration, and a dietary countermeasure would be ideal. We present here preliminary data from a study where we examined the role of dietary intake patterns as one factor that can influence bone mineral loss in astronauts during space flight. Crewmembers (n=5) were asked to consume a prescribed diet with either a low (0.3-0.6) or high (1.0-1.3) ratio of animal protein to potassium (APro:K) before and during space flight for 4-d periods. Diets were controlled for energy, total protein, calcium, and sodium. 24-h urine samples were collected on the last day of each of the 4-d controlled diet sessions. 24-h urinary acid excretion, which was predicted by dietary potential renal acid load, was correlated with urinary n-telopeptide (NTX, Pearson R = 0.99 and 0.80 for the high and low APro:K sessions, respectively, p<0.001). The amount of protein when expressed as the percentage of total energy (but not as total grams) was also correlated with urinary NTX (R = 0.66, p<0.01). These results, from healthy individuals in a unique environment, will be important to better understand diet and bone interrelationships during space flight as well as on Earth. The study was funded by the NASA Human Research Program.

The effect of supplemental oral phosphate on the bone mineral changes during prolonged bed rest

PubMed Central

Hulley, Stephen B.; Vogel, John M.; Donaldson, Charles L.; Bayers, Jon H.; Friedman, Ronald J.; Rosen, Sheldon N.

1971-01-01

Five healthy young men were studied during 24-30 wk of continuous bed rest. During the first 12 wk of bed rest, untreated subjects increased calcium excretion in the urine by 109 mg/day and in the feces by 147 mg/day. The rate of total body calcium loss was 0.5-0.7% per month. Losses of central calcaneus mineral, assessed by gamma ray transmission scanning, occurred at a tenfold higher rate, whereas the mineral content of the radius did not change. Changes in phosphorus balance resembled the calcium pattern, and increased excretion of nitrogen and hydroxyproline also occurred during bed rest. Upon reambulation, the subjects' calcium balance became positive in 1 month and recovery of their calcaneus mineral was complete within 10-20 wk. Treatment with potassium phosphate supplements (1327 mg P/day) entirely prevented the hypercalciuria of bed rest, but fecal calcium tended to increase. During the first 12 wk, calcium balance was slightly less negative (mean - 193 mg/day) than during bed rest without added phosphate (mean - 267 mg/day). This effect was not seen during the second 12 wk of bed rest. The patterns of magnesium excretion were similar to those of calcium. Fecal and urinary phosphorus excretions were doubled, and phosphorus balance became positive (+ 113 mg/day). Mineral loss from the central calcaneus was similar to that of untreated subjects. It is concluded that this form of phosphate supplementation reduces urinary calcium excretion but does not prevent bone loss during bed rest. PMID:5129304

[Anatomy, physiology and clinical relevance of the connecting tubule].

PubMed

Miranda, N; Simeoni, M A; Ciriana, E; Panico, C; Cappello, E; Capasso, G B

2009-01-01

The cortical distal nephron is the site of fine regulation of salt and water excretion by peptide and mineralocorticoid hormones and the site for specific actions of diuretics. Some data suggest that sodium reabsorption and potassium secretion in the distal convoluted tubule and the connecting tubule (CNT) are sufficient to maintain the sodium and potassium balance, with little or no contribution of the collecting duct. The homeostatic role of the sodium and potassium transport systems in the collecting duct can be questioned, especially in conditions where dietary sodium intake is high and potassium intake is low compared with the physiological needs of the organism. The functional expression of epithelial sodium channels (ENaC) in the CNT is sufficient for furosemide-stimulated urinary acidification and identifies the CNT as a major segment in electrogenic urinary acidification. In the outer renal cortex, the CNT returns to the glomerular hilus and contacts the renal afferent arterioles (Af-Art). This morphology is compatible with a cross-talk between the CNT and Af-Art. This novel regulatory mechanism of the renal microcirculation may participate in the vasodilatation observed during high salt intake, perhaps by antagonizing tubuloglomerular feedback. In conclusion, the cortical distal nephron appears to be a complex site for several physiological mechanisms; it is mainly involved in salt and fluid homeostasis and in acid-base balance maintenance. Furthermore, the CNT segment appears to promote a CNT-Af-Art feedback loop.

Renal Stone Risk during Spaceflight: Assessment and Countermeasure Validation

NASA Technical Reports Server (NTRS)

Whitson, Peggy A.; Pietrzyk, Robert A.; Jones, Jeffery A.; Sams, Clarence F.; Hudson, Ed K.; Nelman-Gonzalez, Mayra

2009-01-01

NASA's Vision for Space Exploration centers on exploration class missions including the goals of returning to the moon and landing on Mars. One of NASA's objectives is to focus research on astronaut health and the development of countermeasures that will protect crewmembers during long duration voyages. Exposure to microgravity affects human physiology and results in changes in the urinary chemical composition favoring urinary supersaturation and an increased risk of stone formation. Nephrolithiasis is a multifactorial disease and development of a renal stone is significantly influenced by both dietary and environmental factors. Previous results from long duration Mir and short duration Shuttle missions have shown decreased urine volume, pH, and citrate levels and increased calcium. Citrate, an important inhibitor of calcium-containing stones, binds with urinary calcium reducing the amount of calcium available to form stones. Citrate inhibits renal stone recurrence by preventing crystal growth, aggregation, and nucleation and is one of the most common therapeutic agents used to prevent stone formation. Methods: Thirty long duration crewmembers (29 male, 1 female) participated in this study. 24-hour urines were collected and dietary monitoring was performed pre-, in-, and postflight. Crewmembers in the treatment group received two potassium citrate (KCIT) pills, 10 mEq/pill, ingested daily beginning 3 days before launch, all in-flight days and through 14 days postflight. Urinary biochemical and dietary analyses were completed. Results: KCIT treated subjects exhibited decreased urinary calcium excretion and maintained the levels of calcium oxalate supersaturation risk at their preflight levels. The increased urinary pH levels in these subjects reduced the risk of uric acid stones. Discussion: The current study investigated the use of potassium citrate as a countermeasure to minimize the risk of stone formation during ISS missions. Results suggest that supplementation with potassium citrate decreases the risk of stone formation during and immediately after spaceflight.

Renal function in hepatosplenic schistosomiasis--an assessment of renal tubular disorders.

PubMed

Duarte, Daniella Bezerra; Vanderlei, Lucas Alexandre; Bispo, Raianne Kívia de Azevêdo; Pinheiro, Maria Eliete; da Silva, Geraldo Bezerra; Martins, Alice Maria Costa; Meneses, Gdayllon Cavalcante; Daher, Elizabeth De Francesco

2014-01-01

Renal involvement in Schistosoma mansoni infection is not well studied. The aim of this study is to investigate the occurrence of renal abnormalities in patients with hepatosplenic schistosomiasis (HSS), especially renal tubular disorders. This is a cross-sectional study with 20 consecutive patients with HSS followed in a medical center in Maceió, Alagoas, Brazil. Urinary acidification and concentration tests were performed using calcium chloride (CaCl2) after a 12-h period of water and food deprivation. The biomarker monocyte chemoattractant protein 1 (MCP-1) was quantified in urine. Fractional excretion of sodium (FENa+), transtubular potassium gradient (TTKG) and solute-free water reabsorption (TcH2O) were calculated. The HSS group was compared to a group of 17 healthy volunteers. Patients' mean age and gender were similar to controls. Urinary acidification deficit was found in 45% of HSS patients. Urinary osmolality was significantly lower in HSS patients (588 ± 112 vs. 764 ± 165 mOsm/kg, p = 0,001) after a 12-h period of water deprivation. TcH2O was lower in HSS patients (0.72 ± 0.5 vs. 1.1 ± 0.3, p = 0.04). Urinary concentration deficit was found in 85% of HSS patients. The values of MCP-1 were higher in HSS group than in control group (122 ± 134 vs. 40 ± 28 pg/mg-Cr, p = 0.01) and positively correlated with the values of microalbuminuria and proteinuria. HSS is associated with important kidney dysfunction. The main abnormalities found were urinary concentrating ability and incomplete distal acidification defect, demonstrating the occurrence of tubular dysfunction. There was also an increase in urinary MCP-1, which appears to be a more sensitive marker of renal damage than urinary albumin excretion rate.

Association of urinary calcium excretion with serum calcium and vitamin D levels.

PubMed

Rathod, Anita; Bonny, Olivier; Guessous, Idris; Suter, Paolo M; Conen, David; Erne, Paul; Binet, Isabelle; Gabutti, Luca; Gallino, Augusto; Muggli, Franco; Hayoz, Daniel; Péchère-Bertschi, Antoinette; Paccaud, Fred; Burnier, Michel; Bochud, Murielle

2015-03-06

Population-based data on urinary calcium excretion are scarce. The association of serum calcium and circulating levels of vitamin D [25(OH)D2 or D3] with urinary calcium excretion in men and women from a population-based study was explored. Multivariable linear regression was used to explore factors associated with square root-transformed 24-hour urinary calcium excretion (milligrams per 24 hours) taken as the dependent variable with a focus on month-specific vitamin D tertiles and serum calcium in the Swiss Survey on Salt Study. In total, 624 men and 669 women were studied with mean ages of 49.2 and 47.0 years, respectively (age range=15-95 years). Mean urinary calcium excretion was higher in men than in women (183.05 versus 144.60 mg/24 h; P<0.001). In adjusted models, the association (95% confidence interval) of square root urinary calcium excretion with protein-corrected serum calcium was 1.78 (95% confidence interval, 1.21 to 2.34) mg/24 h per milligram per deciliter in women and 0.59 (95% confidence interval, -0.11 to 1.29) mg/24 h per milligram per deciliter in men. Men in the third 25(OH)D3 tertile had higher square root urinary calcium excretion than men in the first tertile (0.99; 95% confidence interval, 0.36 to 1.63 mg/24 h per nanogram per milliliter), and the corresponding association was 0.32 (95% confidence interval, -0.22 to 0.85) mg/24 h per nanogram per milliliter in women. These sex differences were more marked under conditions of high urinary sodium or urea excretions. There was a positive association of serum calcium with urinary calcium excretion in women but not men. Vitamin 25(OH)D3 was associated with urinary calcium excretion in men but not women. These results suggest important sex differences in the hormonal and dietary control of urinary calcium excretion. Copyright © 2015 by the American Society of Nephrology.

Influence of BMI in nephrolithiasis in an Appalachian pediatric population: A single-center experience.

PubMed

Murphy, Margaret O; Erpelding, Scott G; Chishti, Aftab S; Dugan, Adam; Ziada, Ali; Kiessling, Stefan G

2018-06-07

The prevalence of pediatric nephrolithiasis has increased significantly in the past 20 years. Metabolic abnormalities predisposing adults to nephrolithiasis in obese patients include increased urinary sodium and uric acid excretion as well as low urine pH; however, limited data are available in the pediatric population. The aim was to investigate whether obese pediatric patients presenting with nephrolithiasis have a unique metabolic profile similar to reported findings in obese adults with nephrolithiasis. A retrospective chart review was performed in children aged 1-18 years seen at Kentucky Children's Hospital between 2010 and 2016. Inclusion criteria included all patients with documented stones confirmed by ultrasonography or computed tomography. A total of 111 patient charts were reviewed in the study with a mean age of 11.8 ± 4.2 years. Seventy patients (63%) had a normal BMI and 41 patients (37%) were considered overweight/obese. There was no statistically significant relationship between BMI and stone recurrence. Obese patients had significantly decreased levels of urinary citrate, oxalate, magnesium, and potassium with significant elevations of urinary urea nitrogen, ammonia, and low urine pH compared with normal weight patients (Summary Figure). Several groups have reported on metabolic findings within obese and non-obese pediatric patients. A Turkish study reported increased oxalate excretion and hypocitraturia in obese patients while a Korean study also reported increased rates of hypocitraturia in recurrent stone formers. Similar to these studies, we did find significant differences in citrate within our study population; however, we found significantly lower levels of urinary oxalate in obese patients. The majority of these studies do not report an association with BMI and urine pH although this has been reported in the adult population and our findings support an inverse relationship between body mass index (BMI) and pH. Our group found a higher level of calcium phosphate stones, supporting of Eisner's findings that high BMI is associated with increased supersaturation of calcium phosphate. Limitations of our study include being a single center and retrospective in nature. Our study demonstrates differences in types of stones and urinary metabolites in an obese pediatric population suggestive of different metabolic profiles contributing to stone disease. We report similar association between BMI and urine pH, urinary potassium, and citrate. This study confirmed our primary hypothesis that obese pediatric patients would have a different urinary mineral profile as evidenced by lower levels of citrate and potassium and low urine pH; however, obese patients did not exhibit significantly elevated urinary sodium and uric acid when normalized to weight, as described in the adult population. Our study did not confirm our secondary hypothesis that stone composition would be associated with BMI status or stone recurrence. Copyright © 2018 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Reproducibility of urinary biomarkers in multiple 24-h urine samples.

PubMed

Sun, Qi; Bertrand, Kimberly A; Franke, Adrian A; Rosner, Bernard; Curhan, Gary C; Willett, Walter C

2017-01-01

Limited knowledge regarding the reproducibility of biomarkers in 24-h urine samples has hindered the collection and use of the samples in epidemiologic studies. We aimed to evaluate the reproducibility of various markers in repeat 24-h urine samples. We calculated intraclass correlation coefficients (ICCs) of biomarkers measured in 24-h urine samples that were collected in 3168 participants in the NHS (Nurses' Health Study), NHSII (Nurses' Health Study II), and Health Professionals Follow-Up Study. In 742 women with 4 samples each collected over the course of 1 y, ICCs for sodium were 0.32 in the NHS and 0.34 in the NHSII. In 2439 men and women with 2 samples each collected over 1 wk to ≥1 mo, the ICCs ranged from 0.33 to 0.68 for sodium at various intervals between collections. The urinary excretion of potassium, calcium, magnesium, phosphate, sulfate, and other urinary markers showed generally higher reproducibility (ICCs >0.4). In 47 women with two 24-h urine samples, ICCs ranged from 0.15 (catechin) to 0.75 (enterolactone) for polyphenol metabolites. For phthalates, ICCs were generally ≤0.26 except for monobenzyl phthalate (ICC: 0.55), whereas the ICC was 0.39 for bisphenol A (BPA). We further estimated that, for the large majority of the biomarkers, the mean of three 24-h urine samples could provide a correlation of ≥0.8 with true long-term urinary excretion. These data suggest that the urinary excretion of various biomarkers, such as minerals, electrolytes, most polyphenols, and BPA, is reasonably reproducible in 24-h urine samples that are collected within a few days or ≤1 y. Our findings show that three 24-h samples are sufficient for the measurement of long-term exposure status in epidemiologic studies. © 2017 American Society for Nutrition.

Reproducibility of urinary biomarkers in multiple 24-h urine samples123

PubMed Central

Sun, Qi; Bertrand, Kimberly A; Franke, Adrian A; Rosner, Bernard; Curhan, Gary C; Willett, Walter C

2017-01-01

Background: Limited knowledge regarding the reproducibility of biomarkers in 24-h urine samples has hindered the collection and use of the samples in epidemiologic studies. Objective: We aimed to evaluate the reproducibility of various markers in repeat 24-h urine samples. Design: We calculated intraclass correlation coefficients (ICCs) of biomarkers measured in 24-h urine samples that were collected in 3168 participants in the NHS (Nurses’ Health Study), NHSII (Nurses’ Health Study II), and Health Professionals Follow-Up Study. Results: In 742 women with 4 samples each collected over the course of 1 y, ICCs for sodium were 0.32 in the NHS and 0.34 in the NHSII. In 2439 men and women with 2 samples each collected over 1 wk to ≥1 mo, the ICCs ranged from 0.33 to 0.68 for sodium at various intervals between collections. The urinary excretion of potassium, calcium, magnesium, phosphate, sulfate, and other urinary markers showed generally higher reproducibility (ICCs >0.4). In 47 women with two 24-h urine samples, ICCs ranged from 0.15 (catechin) to 0.75 (enterolactone) for polyphenol metabolites. For phthalates, ICCs were generally ≤0.26 except for monobenzyl phthalate (ICC: 0.55), whereas the ICC was 0.39 for bisphenol A (BPA). We further estimated that, for the large majority of the biomarkers, the mean of three 24-h urine samples could provide a correlation of ≥0.8 with true long-term urinary excretion. Conclusions: These data suggest that the urinary excretion of various biomarkers, such as minerals, electrolytes, most polyphenols, and BPA, is reasonably reproducible in 24-h urine samples that are collected within a few days or ≤1 y. Our findings show that three 24-h samples are sufficient for the measurement of long-term exposure status in epidemiologic studies. PMID:28049663

Urine Potassium Excretion, Kidney Failure, and Mortality in CKD.

PubMed

Leonberg-Yoo, Amanda K; Tighiouart, Hocine; Levey, Andrew S; Beck, Gerald J; Sarnak, Mark J

2017-03-01

Low urine potassium excretion, as a surrogate for dietary potassium intake, is associated with higher risk for hypertension and cardiovascular disease in a general population. Few studies have investigated the relationship of urine potassium with clinical outcomes in chronic kidney disease (CKD). Longitudinal cohort study. The MDRD (Modification of Diet in Renal Disease) Study was a randomized controlled trial (N = 840) conducted in 1989 to 1993 to examine the effects of blood pressure control and dietary protein restriction on kidney disease progression in adults aged 18 to 70 years with CKD stages 2 to 4. This post hoc analysis included 812 participants. The primary predictor variable was 24-hour urine potassium excretion, measured at baseline and at multiple time points (presented as time-updated average urine potassium excretion). Kidney failure, defined as initiation of dialysis therapy or transplantation, was determined from US Renal Data System data. All-cause mortality was assessed using the National Death Index. Median follow-up for kidney failure was 6.1 (IQR, 3.5-11.7) years, with 9 events/100 patient-years. Median all-cause mortality follow-up was 19.2 (IQR, 10.8-20.6) years, with 3 deaths/100 patient-years. Baseline mean urine potassium excretion was 2.39±0.89 (SD) g/d. Each 1-SD higher baseline urine potassium level was associated with an adjusted HR of 0.95 (95% CI, 0.87-1.04) for kidney failure and 0.83 (95% CI, 0.74-0.94) for all-cause mortality. Results were consistent using time-updated average urine potassium measurements. Analyses were performed using urine potassium excretion as a surrogate for dietary potassium intake. Results are obtained from a primarily young, nondiabetic, and advanced CKD population and may not be generalizable to the general CKD population. Higher urine potassium excretion was associated with lower risk for all-cause mortality, but not kidney failure. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Association between 24-h urinary sodium excretion and obesity in Korean adults: A multicenter study.

PubMed

Nam, Ga Eun; Kim, Seon Mee; Choi, Mi-Kyeong; Heo, Young-Ran; Hyun, Tai-Sun; Lyu, Eun-Soon; Oh, Se-Young; Park, Hae-Ryun; Ro, Hee-Kyong; Han, Kyungdo; Lee, Yeon Kyung

2017-09-01

The aim of this study was to explore the association between sodium intake, as assessed by 24-h urinary sodium excretion, and various obesity parameters among South Korean adults. The associations of 24-h urinary sodium excretion and sodium intake calculated from the dietary questionnaire with obesity parameters also were compared. This multicenter, cross-sectional study analyzed data of 640 healthy adults from eight provinces in South Korea. Obesity was assessed by body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR). Mean 24-h urinary sodium excretion was calculated from repeatedly collected 24-h urine samples. Participants' dietary intake was assessed by 24-h dietary recall interview on the days before 24-h urine collection. In both sexes, the means of all anthropometric measurements tended to increase proportionally with 24-h urinary sodium excretion quartiles, regardless of adjustment. Men in the highest quartile (Q4) of 24-h urinary sodium excretion had increased odds of obesity (as assessed by BMI, WC, WHR, and WHtR) compared with men in the three lower quartiles (Q1-Q3) of 24-h urinary sodium excretion. Women in Q4 of 24-h urinary sodium excretion exhibited a higher chance of general obesity and abdominal obesity. Sodium intake calculated from the dietary questionnaire was not significantly associated with obesity in either sex. In Korean adults, there was a positive association between higher sodium intake as assessed by 24-h urinary sodium excretion and obesity independent of energy intake. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of cooking using multi-ply cookware on absorption of potassium and vitamins: a randomized double-blind placebo control study

PubMed Central

Mori, Mari; Hamada, Atsumi; Mori, Hideki; Yamori, Yukio; Tsuda, Kinsuke

2012-01-01

This 2-week interventional study involved a randomized allocation of subjects into three groups: Group A (daily ingestion of 350 g vegetables cooked without water using multi-ply [multilayer-structured] cookware), Group B (daily ingestion of 350g vegetables; ordinary cookware) and Group C (routine living). Before and after intervention, each subject underwent health examination with 24-h urine sampling. Blood vitamin C significantly increased after intervention from the baseline in Group A (P < 0.01) and Group B (P < 0.05). β-Carotene levels also increased significantly after intervention in Group A (P < 0.01) and Group B (P < 0.01). Oxidized low-density lipoprotein decreased significantly after intervention in Group A (P < 0.01). In Group A, 24-h urinary potassium excretion increased significantly (P < 0.01) and 24-h urinary sodium (Na)/K ratio improved significantly (P < 0.05) after intervention. In conclusion, a cooking method modification with multi-ply cookware improved absorption of nutrients from vegetables and enhanced effective utilization of the antioxidant potentials of vegetable nutrients. PMID:22229802

Protective Effect of Propolis in Proteinuria, Crystaluria, Nephrotoxicity and Hepatotoxicity Induced by Ethylene Glycol Ingestion.

PubMed

El Menyiy, Nawal; Al Waili, Noori; Bakour, Meryem; Al-Waili, Hamza; Lyoussi, Badiaa

2016-10-01

Propolis is a natural honeybee product with wide biological activities and potential therapeutic properties. The aim of the study is to evaluate the protective effect of propolis extract on nephrotoxicity and hepatotoxicity induced by ethylene glycol in rats. Five groups of rats were used. Group 1 received drinking water, group 2 received 0.75% ethylene-glycol in drinking water, group 3 received 0.75% ethylene-glycol in drinking water along with cystone 500 mg/kg/body weight (bw) daily, group 4 received 0.75% ethylene-glycol in drinking water along with propolis extract at a dose of 100 mg/kg/bw daily, and group 5 received 0.75% ethylene-glycol in drinking water along with propolis extract at a dose of 250 mg/kg/bw daily. The treatment continued for a total of 30 d. Urinalyses for pH, crystals, protein, creatinine, uric acid and electrolytes, and renal and liver function tests were performed. Ethylene-glycol increased urinary pH, urinary volume, and urinary calcium, phosphorus, uric acid and protein excretion. It decreased creatinine clearance and magnesium and caused crystaluria. Treatment with propolis extract or cystone normalized the level of magnesium, creatinine, sodium, potassium and chloride. Propolis is more potent than cystone. Propolis extract alleviates urinary protein excretion and ameliorates the deterioration of liver and kidney function caused by ethylene glycol. Propolis extract has a potential protective effect against ethylene glycol induced hepatotoxicity and nephrotoxicity and has a potential to treat and prevent urinary calculus, crystaluria and proteinuria. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

Dietary intake and urinary excretion of lignans in Finnish men.

PubMed

Nurmi, Tarja; Mursu, Jaakko; Peñalvo, José L; Poulsen, Henrik E; Voutilainen, Sari

2010-03-01

Intake of lignans has been assessed in different study populations, but so far none of the studies has compared the daily intake of lignans and the urinary excretion of plant and enterolignans. We assessed the intake of lariciresinol, pinoresinol, secoisolariciresinol and matairesinol in 100 Finnish men consuming their habitual omnivorous diet, and measured the 24 h urinary excretion of plant and enterolignans to compare the intake and metabolism. Dietary determinants of lignan intake and their urinary excretion were also determined. The mean intake of lignans was 1224 (sd 539) mug/d, of which lariciresinol and pinoresinol covered 78 %. Almost half (47 %) of the intake of lignans was explained by the intake of rye products, berries, coffee, tea and roots. The urinary excretion of plant lignans corresponded to 17 % and enterolignans to 92 % of the intake of lignans. The urinary excretion of plant lignans was explained 14 % by the intake of rye products and intake of coffee, and consequently 3-7 % by the intake of water-insoluble fibre. The urinary excretion of enterolactone was explained 11 % by the intake of vegetables and rye products, 14 % by the intake of water-soluble fibre and only 4 % by the intake of lariciresinol. Although the assessed intake of lignans corresponded well with the urinary excretion of lignans, the enterolactone production in the human body depended more on the dietary sources of lignans than the absolute intake of lignans.

Association of Urinary Calcium Excretion with Serum Calcium and Vitamin D Levels

PubMed Central

Rathod, Anita; Bonny, Olivier; Guessous, Idris; Suter, Paolo M.; Conen, David; Erne, Paul; Binet, Isabelle; Gabutti, Luca; Gallino, Augusto; Muggli, Franco; Hayoz, Daniel; Péchère-Bertschi, Antoinette; Paccaud, Fred

2015-01-01

Background and objectives Population-based data on urinary calcium excretion are scarce. The association of serum calcium and circulating levels of vitamin D [25(OH)D2 or D3] with urinary calcium excretion in men and women from a population-based study was explored. Design, settings, participants, & measurements Multivariable linear regression was used to explore factors associated with square root–transformed 24-hour urinary calcium excretion (milligrams per 24 hours) taken as the dependent variable with a focus on month-specific vitamin D tertiles and serum calcium in the Swiss Survey on Salt Study. Results In total, 624 men and 669 women were studied with mean ages of 49.2 and 47.0 years, respectively (age range=15–95 years). Mean urinary calcium excretion was higher in men than in women (183.05 versus 144.60 mg/24 h; P<0.001). In adjusted models, the association (95% confidence interval) of square root urinary calcium excretion with protein–corrected serum calcium was 1.78 (95% confidence interval, 1.21 to 2.34) mg/24 h per milligram per deciliter in women and 0.59 (95% confidence interval, −0.11 to 1.29) mg/24 h per milligram per deciliter in men. Men in the third 25(OH)D3 tertile had higher square root urinary calcium excretion than men in the first tertile (0.99; 95% confidence interval, 0.36 to 1.63 mg/24 h per nanogram per milliliter), and the corresponding association was 0.32 (95% confidence interval, −0.22 to 0.85) mg/24 h per nanogram per milliliter in women. These sex differences were more marked under conditions of high urinary sodium or urea excretions. Conclusions There was a positive association of serum calcium with urinary calcium excretion in women but not men. Vitamin 25(OH)D3 was associated with urinary calcium excretion in men but not women. These results suggest important sex differences in the hormonal and dietary control of urinary calcium excretion. PMID:25518946

Effects of chronic lithium administration on renal acid excretion in humans and rats

PubMed Central

Weiner, I. David; Leader, John P.; Bedford, Jennifer J.; Verlander, Jill W.; Ellis, Gaye; Kalita, Priyakshi; Vos, Frederiek; de Jong, Sylvia; Walker, Robert J.

2014-01-01

Abstract Lithium therapy's most common side effects affecting the kidney are nephrogenic diabetes insipidus (NDI) and chronic kidney disease. Lithium may also induce a distal renal tubular acidosis. This study investigated the effect of chronic lithium exposure on renal acid–base homeostasis, with emphasis on ammonia and citrate excretion. We compared 11 individuals on long‐term lithium therapy with six healthy individuals. Under basal conditions, lithium‐treated individuals excreted significantly more urinary ammonia than did control subjects. Following an acute acid load, urinary ammonia excretion increased approximately twofold above basal rates in both lithium‐treated and control humans. There were no significant differences between lithium‐treated and control subjects in urinary pH or urinary citrate excretion. To elucidate possible mechanisms, rats were randomized to diets containing lithium or regular diet for 6 months. Similar to humans, basal ammonia excretion was significantly higher in lithium‐treated rats; in addition, urinary citrate excretion was also significantly greater. There were no differences in urinary pH. Expression of the critical ammonia transporter, Rhesus C Glycoprotein (Rhcg), was substantially greater in lithium‐treated rats than in control rats. We conclude that chronic lithium exposure increases renal ammonia excretion through mechanisms independent of urinary pH and likely to involve increased collecting duct ammonia secretion via the ammonia transporter, Rhcg. PMID:25501430

Decreased urinary glycosaminoglycan excretion following alfuzosin treatment on ureteral stent-related symptoms: a prospective, randomized, placebo-controlled study.

PubMed

Liu, Shucheng; Yu, Ying; Gao, Yang; Yang, Xiong; Pang, Zili

2016-04-01

The objectives of the study were to evaluate changes in ureteral stent-related symptoms and urinary glycosaminoglycan (GAG) excretion after alfuzosin treatment, and to further investigate the relationship between stent-related symptoms and loss of urinary GAGs. Seventy consecutive patients scheduled for unilateral retrograde ureteroscopy with stent placement were recruited. Patients were randomly assigned to treatment with alfuzosin 10 mg/day or placebo for 3 weeks starting on the third postoperative day. The ureteral stent was removed when treatment stopped. International Prostate Symptom Score (IPSS), visual analog scale (VAS) score, and urinary GAG excretion were determined before treatment at 1, 2, and 3 weeks after treatment, and at 3 weeks after stent removal. Fifty-nine patients completed the study. IPSS, VAS score, and urinary GAG excretion were significantly lower in the alfuzosin group, compared with the placebo group, at 1, 2, and 3 weeks after treatment (P < 0.01). In both groups, IPSS, VAS score, and urinary GAG excretion were significantly lower at 3 weeks after stent removal compared with those before stent removal. No significant differences in IPSS, VAS score, or urinary GAG excretion were observed between the two groups at baseline and 3 weeks after stent removal (P > 0.05). Positive correlations were found between urinary GAG excretion (R(2) = 0.65, P < 0.001) and IPSS and between urinary GAG excretion and VAS score (R(2) = 0.33, P < 0.001). Stent placement contributes to loss of urinary GAGs. However, alfuzosin effectively reduces such loss and improves ureteral stent-related symptoms. Loss of urinary GAGs plays a role in these symptoms.

Identification and chromosomal localization of ecogenetic components of electrolyte excretion.

PubMed

Dumas, Pierre; Kren, Vladimír; Krenová, Drahomíra; Pravenec, Michal; Hamet, Pavel; Tremblay, Johanne

2002-02-01

To determine to what extent urinary excretion of blood pressure-modulating electrolytes is genetically determined, and to identify their chromosomal localization. Twenty-six rat recombinant inbred strains (RIS) originating from reciprocal crosses of normotensive Brown Norway (BN.Lx) and spontaneously hypertensive rats (SHR) were used. A pilot experiment on a subset of strains determined that fasting decreases the impact of environmental noise and increases that of heritability. Twenty-four-hour urinary collections were obtained from fasting rats aged 6-12 weeks (3-8 rats per strain). Sodium (Na), potassium (K) and calcium (Ca) excretions were measured, and the Na/K ratio calculated. These phenotypes served as quantitative traits for the search of quantitative trait loci (QTLs) by scanning the RIS genome that was mapped with 475 polymorphic markers. Constant Na intake resulted in a low heritability for Na excretion, reflecting the environmental impact (intake = excretion), whereas fasting revealed a gradient among RIS indicative of the genetic component of the traits. In the fasting state, a locus on chromosome 14 was found to be significantly associated with K excretion (Alb, P = 0.00002, r = -0.69, logarithm of the odds score (LOD) 3.9), whereas another locus on chromosome 10 (D10Cebrp97s5, P = 0.0003, r = -0.69, LOD 3.0) and one on chromosome 6 (D6Cebrp97s14, P = 0.0007, r = -0.65, LOD 1.9) were more significantly associated with Na excretion and the Na/K ratio respectively. The observed correlations were all negative for Na, K and Na/K, indicating a higher excretion of Na and K and a greater Na/K ratio in rats bearing BN.Lx alleles at these loci, i.e. salt retention in fasting SHR. These three loci accounted for 47-55% of variance of their associated trait, suggesting that they are the main genetic determinants for these phenotypes in basal fasting conditions. Rats bearing the Y chromosome of SHR origin had significantly higher K excretion that, in turn, led to a significantly lower Na/K ratio. Finally, a locus on chromosome 7 was linked to Ca excretion, explaining 46% of the trait variance (D7Mit10, LOD score 3.0). RIS enabled us to determine QTLs for environmentally modulated traits such as Na, K and Ca excretions. We demonstrated that whereas urinary electrolytes are determined mainly by intake (environment) in a steady state, their excretion in an adaptive state (fasting) is predominantly genetically determined by distinct QTL on autosomes as well as the Y chromosome. Furthermore, the loci responsible for Na and K excretions act independently of the locus governing the relative excretion of Na/K. Thus, the salt-retaining aspects of some hypertensives may be, in large part, determined by genes responsible for renal excretion, the impact of which is predominant over the environment under acute challenge.

Triiodothyronine and thyroxine in urine. II. Renal handling, and effect of urinary protein.

PubMed

Burke, C W; Shakespear, R A

1976-03-01

Mean urinary clearances of T3 were 164 ml/min in normal subjects, 177 in pregnancy, 221 in thyrotoxicosis, 174 in hypothyroidism, and 194 in 3 persons with undetectable T4 but normal T3 levels. T4 clearances were 38 ml/min in normal subjects, 48 in thyrotoxicosis, and 138 in hypothyroidism. Low creatinine clearance was associated with low clearances of T4 and T3. The data suggest urinary excretion of T3 by glomerular filtration of serum unbound T3 with added tubular excretion; and T4 excretion by glomerular filtration of unbound T4 and tubular reabsorption. However, 3-9% of urinary T3 and 5-12% of urinary T4 were bound to urinary proteins, and increased protein excretion caused markedly increased T4 excretion. In addition, 52% of urinary T3 and 68% of urinary T4 were bound to other substances of approximate mol wt 500-2,000, which may influence tubular handling of T3 or T4.

Urinary spot albumin:creatinine ratio for documenting proteinuria in women with preeclampsia.

PubMed

Huang, Qitao; Gao, Yunfei; Yu, Yanhong; Wang, Wei; Wang, Shuoshi; Zhong, Mei

2012-01-01

To assess whether a single urinary spot urinary albumin:creatinine ratio (ACR) can be used to estimate 24-hour urinary protein excretion in women with preeclampsia. ACR and 24-hour urinary protein excretion were measured in 50 consecutive patients with preeclampsia. ACR was determined in a spot midstream urine sample and the amount of protein excretion was quantified in a 24-hour urine collection performed the following day. The correlation between the spot ACR and 24-hour urine protein excretion was assessed, and the diagnostic value of ACR was expressed in terms of specificity and sensitivity. Receiver operating characteristic curve analysis was used to determine the best cutoff values of the spot ACR for mild preeclampsia (proteinuria ≥ 0.3 g/24 h) and severe preeclampsia (defined in China as proteinuria ≥ 2 g/24 h). A strong correlation was evident between the spot ACR and 24-hour urinary protein excretion (r = .938; P < .001). The optimal spot ACR cutoff point was 22.8 mg/mmol for 0.3 g/24 h of protein excretion (mild preeclampsia) with a sensitivity and specificity of 82.4% and 99.4%, respectively, and 155.6 mg/mmol for 2 g/24 h of protein excretion (severe preeclampsia) with a sensitivity and specificity of 90.6% and 99.6%, respectively. Compared with 24-hour urinary protein excretion, the spot urinary ACR may be a simple, convenient, and accurate indicator of significant proteinuria in women with preeclampsia.

Cardiovascular risk factors in two Ecuadorian urban and rural populations. The Ecuadorian-Japan Cooperative CARDIAC Study Group.

PubMed

Del Pozo, G; Davalos, P; Yamori, Y

1990-01-01

We examined the specific hypotheses linking the intake of sodium, potassium, calcium, magnesium, and protein to blood pressure (BP) and the relationship between dietary factors and mortality from the major cardiovascular diseases (CVD) in the Ecuadorian populations. Two Ecuadorian populations, the urban and the rural, were selected from Quito and Vilcabamba, respectively. From Quito: 87 men and 83 women; from Vilcabamba: 71 men and 91 women aged 50-54 were randomly selected for BP measurement, 24-h urine collection, and blood sampling according to the Cardiovascular Disease and Alimentary Comparison (CARDIAC) Study protocol. Samples were analyzed at CARDIAC center in Izumo, Japan. Mean systolic blood pressure (SBP) was not much different in the two populations, but mean diastolic blood pressure (DBP) and body mass index (BMI) were significantly lower in Vilcabamba (p less than 0.001). Mortality from stroke was higher in Vilcabamba, whereas coronary death rate was higher in Quito. Both sodium intake and sodium/potassium ratio were higher in Vilcabamba (p less than 0.001). Protein intake and serum cholesterol were higher in Quito (p less than 0.001). Urinary taurine excretion was higher in Quito. There was no difference in W3/W6 fatty acids ratio between the two populations. Multiple regression analyses of intracommunity correlation indicated that both SBP and DBP were highly significantly related with BMI in Quito and that urinary excretions were inversely related to SBP. Serum cholesterol was positively related to coronary death rate. Mortality from stroke was inversely related to both serum cholesterol and protein and was positively related to salt consumption.

Diet and renal stone formation.

PubMed

Trinchieri, A

2013-02-01

The relationship between diet and the formation of renal stones is demonstrated, but restrictive diets do not take into account the complexity of metabolism and the complex mechanisms that regulate the saturation and crystallization processes in the urine. The restriction of dietary calcium can reduce the urinary excretion of calcium but severe dietary restriction of calcium causes hyperoxaluria and a progressive loss of bone mineral component. Furthermore urinary calcium excretion is influenced by other nutrients than calcium as sodium, potassium, protein and refined carbohydrates. Up to 40% of the daily excretion of oxalate in the urine is from dietary source, but oxalate absorption in the intestine depends linearly on the concomitant dietary intake of calcium and is influenced by the bacterial degradation by several bacterial species of intestinal flora. A more rational approach should be based on the cumulative effects of foods and different dietary patterns on urinary saturation rather than on the effect of single nutrients. A diet based on a adequate intake of calcium (1000-1200 mg per day) and containment of animal protein and salt can decrease significantly urinary supersaturation for calcium oxalate and reduce the relative risk of stone recurrence in hypercalciuric renal stone formers. The DASH-style diet that is high in fruits and vegetables, moderate in low-fat dairy products and low in animal proteins and salt is associated with a lower relative supersaturation for calcium oxalate and a marked decrease in risk of incident stone formation. All the diets above mentioned have as a common characteristic the reduction of the potential acid load of the diet that can be correlated with a higher risk of recurrent nephrolithiasis, because the acid load of diet is inversely related to urinary citrate excretion. The restriction of protein and salt with an adequate calcium intake seem to be advisable but should be implemented with the advice to increase the intake of vegetables that can carry a plentiful supply of alkali that counteract the acid load coming from animal protein. New prospective studies to evaluate the effectiveness of the diet for the prevention of renal stones should be oriented to simple dietary advices that should be focused on a few specific goals easily controlled by means of self-evaluation tools, such as the LAKE food screener.

Normal distribution of urinary polyphenol excretion among Egyptian males 7-14 years old and changes following nutritional intervention with tomato juice (Lycopersicon esculentum).

PubMed

Hussein, Laila; Medina, Alexander; Barrionnevo, Ana; Lammuela-Raventos, Rosa M; Andres-Lacueva, Cristina

2009-06-01

The urinary flavonoids are considered a reliable biomarker for the intake of polyphenol-rich foods. To assess the normal distribution of urinary polyphenol [PP] excretion among healthy male children and adolescents on a typical Egyptian diet. To follow up the impact of nutritional intervention with tomato juice on the urinary excretion of [PP]. Forty-nine male subjects 7-14 years old collected a 24-h urine sample and filled a dietary record during a 7-day period. A daily serving of 230 g fresh tomato juice was followed for 18 days in a subgroup. Total urinary [PP] excretions were measured before and after termination of the intervention program. The total urinary [PP] was analyzed after a clean-up solid-phase extraction step by the Folin-Ciocalteu reagent in the 96 micro plates. The results were expressed as gallic acid equivalents (GAE). The urinary [PP] excretion averaged 48.6+/-5.5 mg GAE/24 h, equivalent to 89.5+/-8.4 mg GAE/g creatinine. The mean urinary [PP] excretion increased significantly (P<0.05) following the intervention with tomato juice (287.4+/-64.3 mg GAE/g creatinine) compared with the respective mean baseline level (94.5+/-8.92 mg GAE/g creatinine). Clinical laboratory reference limits for urinary polyphenols are presented for Egyptian male children and adolescents. Measuring the urinary polyphenol excretion proved a good biomarker for the dietary polyphenol intake and the results demonstrated that tomato [PP] was highly bioavailable in the human body.

Sodium and potassium excretion are related to bone mineral density in women with coeliac disease.

PubMed

Turner, Kirsty M; Clifton, Peter M; Keogh, Jennifer B

2015-04-01

Women with coeliac disease may have a lower bone mineral density due to the malabsorption of calcium before diagnosis. A high sodium excretion is associated with increased calcium and bone loss. Our aim was to describe the bone mineral density (BMD) and sodium excretion in women with coeliac disease. In a cross-sectional study BMD of the lumbar spine and hip was assessed by dual energy X-ray absorptiometry. Sodium, potassium and calcium excretion were measured from a 24 h urine collection. In 33 women (51 ± 16 yr) BMD was 1.14 ± 0.19 g/cm(2) and 0.94 ± 0.14 g/cm(2) at the lumbar spine and hip respectively. Age matched Z-scores were -0.1 ± 1.2 and -0.3 ± 1.1 at lumbar spine and hip respectively. Sodium excretion was 107 ± 51 mmol/d; 14 (42%) had a sodium excretion >100 mmol Na/d (145 ± 45 mmol/d). Potassium and calcium excretion were 87 ± 25 mmol/d and 4.1 ± 2.0 mmol/d respectively. In women with Na excretion >100 mmol Na/d, Ca excretion was significantly greater than those with <100 mmol/d (4.9 ± 2.0 vs 3.4 ± 1.8, p < 0.05). Sodium excretion and BMI were positively correlated (r = 0.61, p < 0.001) as were sodium and calcium excretion (r = 0.43, p < 0.05). Sodium excretion was inversely related to femoral neck BMD (t = -2.4 p = 0.023) after adjustment for weight, age, years since diagnosis and potassium excretion. Weight, but no other variable, was a predictor of BMD at the lumbar spine (t = 2.58 p = 0.018). Sodium excretion was inversely related and potassium excretion positively related to femoral neck density which was similar to age matched women without coeliac disease. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Association between urinary sodium excretion and uric acid, and its interaction on the risk of prehypertension among Chinese young adults.

PubMed

Wang, Yang; Hu, Jia-Wen; Qu, Peng-Fei; Wang, Ke-Ke; Yan, Yu; Chu, Chao; Zheng, Wen-Ling; Xu, Xian-Jing; Lv, Yong-Bo; Ma, Qiong; Gao, Ke; Yuan, Yue; Li, Hao; Yuan, Zu-Yi; Mu, Jian-Jun

2018-05-17

High uric acid (UA) level and high salt intake are reportedly associated with cardiovascular disease. This study investigated the association between UA and urinary sodium excretion, as well as its interaction on the risk of prehypertension. A total of 1869 participants without hypertension were recruited from a previously established cohort in Shaanxi Province, China. The participants were classified as normotensive or prehypertensive on the basis of their blood pressure. Increasing quartiles of sodium excretion were associated with high urinary UA/creatinine levels in prehypertensive participants. Estimated sodium excretion positively correlated with urinary UA/creatinine excretions in the prehypertensive group. In addition, the multivariate-adjusted odds ratios for prehypertension compared with normotension were 1.68 (1.27-2.22) for sodium excretion and 1.71 (1.21-2.42) for serum UA. Increasing sodium excretion and serum UA were associated with higher risk of prehypertension. Compared with the lowest quartiles, the highest sodium excretion and serum UA quartiles entailed 3.48 times greater risk of prehypertension. Sodium excretion is associated with urinary UA excretion in prehypertensive participants. The present study shows that high levels of salt intake and serum UA simultaneously are associated with a higher risk of prehypertension.

Bioavailability of potassium from potatoes and potassium gluconate: a randomized dose response trial.

PubMed

Macdonald-Clarke, Claire J; Martin, Berdine R; McCabe, Linda D; McCabe, George P; Lachcik, Pamela J; Wastney, Meryl; Weaver, Connie M

2016-08-01

The bioavailability of potassium should be considered in setting requirements, but to our knowledge, the bioavailability from individual foods has not been determined. Potatoes provide 19-20% of potassium in the American diet. We compared the bioavailability and dose response of potassium from nonfried white potatoes with skin [targeted at 20, 40, and 60 milliequivalents (mEq) K] and French fries (40 mEq K) with potassium gluconate at the same doses when added to a basal diet that contained ∼60 mEq K. Thirty-five healthy, normotensive men and women with a mean ± SD age of 29.7 ± 11.2 y and body mass index (in kg/m(2)) of 24.3 ± 4.4 were enrolled in a single-blind, crossover, randomized controlled trial. Participants were partially randomly assigned to the order of testing for nine 5-d interventions of additional potassium as follows: 0 (control; repeated at phases 1 and 5), 20, 40, and 60 mEq K/d consumed as a potassium gluconate supplement or as unfried potato or 40 mEq K from French fries completed at phase 9. The bioavailability of potassium was determined from the area under the curve (AUC) of serial blood draws and cumulative urinary excretion during a 24-h period and from a kinetic analysis. The effects of the potassium source and dose on the change in blood pressure and augmentation index (AIx) were determined. The serum potassium AUC increased with the dose (P < 0.0001) and did not differ because of the source (P = 0.53). Cumulative 24-h urinary potassium also increased with the dose (P < 0.0001) and was greater with the potato than with the supplement (P < 0.0001). The kinetic analysis showed the absorption efficiency was high across all interventions (>94% ± 12%). There were no significant differences in the change in blood pressure or AIx with the treatment source or dose. The bioavailability of potassium is as high from potatoes as from potassium gluconate supplements. Future studies that measure the effect of dietary potassium on blood pressure will need to evaluate the effect of various dietary sources on potassium retention and in both normal and hypertensive populations. This trial was registered at clinicaltrials.gov as NCT01881295. © 2016 American Society for Nutrition.

Monosodium glutamate (MSG) consumption is associated with urolithiasis and urinary tract obstruction in rats.

PubMed

Sharma, Amod; Prasongwattana, Vitoon; Cha'on, Ubon; Selmi, Carlo; Hipkaeo, Wiphawi; Boonnate, Piyanard; Pethlert, Supattra; Titipungul, Tanin; Intarawichian, Piyapharom; Waraasawapati, Sakda; Puapiroj, Anucha; Sitprija, Visith; Reungjui, Sirirat

2013-01-01

The peritoneal injection of monosodium glutamate (MSG) can induce kidney injury in adult rats but the effects of long-term oral intake have not been determined. We investigated the kidney histology and function in adult male Wistar rats that were fed ad libitum with a standard rat chow pellet and water with or without the addition of 2 mg/g body weight MSG/day in drinking water (n=10 per group). Both MSG-treated and control animals were sacrificed after 9 months when renal function parameters, blood and urine electrolytes, and tissue histopathology were determined. MSG-treated rats were more prone to kidney stone formation, as represented by the alkaline urine and significantly higher activity product of calcium phosphate. Accordingly, 3/10 MSG-treated rats developed kidney stones over 9 months versus none of the control animals. Further, 2/10 MSG-treated rats but none (0/10) of the controls manifested hydronephrosis. MSG-treated rats had significantly higher levels of serum creatinine and potassium including urine output volume, urinary excretion sodium and citrate compared to controls. In contrast, MSG-treated rats had significantly lower ammonium and magnesium urinary excretion. Oral MSG consumption appears to cause alkaline urine and may increase the risks of kidney stones with hydronephrosis in rats. Similar effects in humans must be verified by dedicated studies.

Monosodium Glutamate (MSG) Consumption Is Associated with Urolithiasis and Urinary Tract Obstruction in Rats

PubMed Central

Sharma, Amod; Prasongwattana, Vitoon; Cha’on, Ubon; Selmi, Carlo; Hipkaeo, Wiphawi; Boonnate, Piyanard; Pethlert, Supattra; Titipungul, Tanin; Intarawichian, Piyapharom; Waraasawapati, Sakda; Puapiroj, Anucha; Sitprija, Visith; Reungjui, Sirirat

2013-01-01

Background The peritoneal injection of monosodium glutamate (MSG) can induce kidney injury in adult rats but the effects of long-term oral intake have not been determined. Methods We investigated the kidney histology and function in adult male Wistar rats that were fed ad libitum with a standard rat chow pellet and water with or without the addition of 2 mg/g body weight MSG/day in drinking water (n=10 per group). Both MSG-treated and control animals were sacrificed after 9 months when renal function parameters, blood and urine electrolytes, and tissue histopathology were determined. Results MSG-treated rats were more prone to kidney stone formation, as represented by the alkaline urine and significantly higher activity product of calcium phosphate. Accordingly, 3/10 MSG-treated rats developed kidney stones over 9 months versus none of the control animals. Further, 2/10 MSG-treated rats but none (0/10) of the controls manifested hydronephrosis. MSG-treated rats had significantly higher levels of serum creatinine and potassium including urine output volume, urinary excretion sodium and citrate compared to controls. In contrast, MSG-treated rats had significantly lower ammonium and magnesium urinary excretion. Conclusion Oral MSG consumption appears to cause alkaline urine and may increase the risks of kidney stones with hydronephrosis in rats. Similar effects in humans must be verified by dedicated studies. PMID:24086562

Concave Urinary Crystallines: Direct Evidence of Calcium Oxalate Crystals Dissolution by Citrate In Vivo

PubMed Central

Shang, Yun-Feng; Xu, Meng; Zhang, Guang-Na; Ouyang, Jian-Ming

2013-01-01

The changes in urinary crystal properties in patients with calcium oxalate (CaOx) calculi after oral administration of potassium citrate (K3cit) were investigated via atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray powder diffractometry (XRD), and zeta potential analyzer. The AFM and SEM results showed that the surface of urinary crystals became concave, the edges and corners of crystals became blunt, the average size of urinary crystallines decreased significantly, and aggregation of urinary crystals was reduced. These changes were attributed to the significant increase in concentration of excreted citrate to 492 ± 118 mg/L after K3cit intake from 289 ± 83 mg/L before K3cit intake. After the amount of urinary citrate was increased, it complexed with Ca2+ ions on urinary crystals, which dissolved these crystals. Thus, the appearance of concave urinary crystals was a direct evidence of CaOx dissolution by citrate in vivo. The XRD results showed that the quantities and species of urinary crystals decreased after K3cit intake. The mechanism of inhibition of formation of CaOx stones by K3cit was possibly due to the complexation of Ca2+ with citrate, increase in urine pH, concentration of urinary inhibitor glycosaminoglycans (GAGs), and the absolute value of zeta potential after K3cit intake. PMID:24363634

Diet, but not oral probiotics, effectively reduces urinary oxalate excretion and calcium oxalate supersaturation.

PubMed

Lieske, John C; Tremaine, William J; De Simone, Claudio; O'Connor, Helen M; Li, Xujian; Bergstralh, Eric J; Goldfarb, David S

2010-12-01

We examined the effect of a controlled diet and two probiotic preparations on urinary oxalate excretion, a risk factor for calcium oxalate kidney stone formation, in patients with mild hyperoxaluria. Patients were randomized to a placebo, a probiotic, or a synbiotic preparation. This tested whether these probiotic preparations can increase oxalate metabolism in the intestine and/or decrease oxalate absorption from the gut. Patients were maintained on a controlled diet to remove the confounding variable of differing oxalate intake from food. Urinary oxalate excretion and calcium oxalate supersaturation on the controlled diet were significantly lower compared with baseline on a free-choice diet. Neither study preparation reduced urinary oxalate excretion nor calcium oxalate supersaturation. Fecal lactobacilli colony counts increased on both preparations, whereas enterococcal and yeast colony counts were increased on the synbiotic. Total urine volume and the excretion of oxalate and calcium were all strong independent determinants of urinary calcium oxalate supersaturation. Hence, dietary oxalate restriction reduced urinary oxalate excretion, but the tested probiotics did not influence urinary oxalate levels in patients on a restricted oxalate diet. However, this study suggests that dietary oxalate restriction is useful for kidney stone prevention.

First-in-Man Demonstration of Direct Endothelin-Mediated Natriuresis and Diuresis

PubMed Central

Hunter, Robert W.; Moorhouse, Rebecca; Farrah, Tariq E.; MacIntyre, Iain M.; Asai, Takae; Gallacher, Peter J.; Kerr, Debbie; Melville, Vanessa; Czopek, Alicja; Morrison, Emma E.; Ivy, Jess R.; Dear, James W.; Bailey, Matthew A.; Goddard, Jane; Webb, David J.

2017-01-01

Endothelin (ET) receptor antagonists are potentially novel therapeutic agents in chronic kidney disease and resistant hypertension, but their use is complicated by sodium and water retention. In animal studies, this side effect arises from ETB receptor blockade in the renal tubule. Previous attempts to determine whether this mechanism operates in humans have been confounded by the hemodynamic consequences of ET receptor stimulation/blockade. We aimed to determine the effects of ET signaling on salt transport in the human nephron by administering subpressor doses of the ET-1 precursor, big ET-1. We conducted a 2-phase randomized, double-blind, placebo-controlled crossover study in 10 healthy volunteers. After sodium restriction, subjects received either intravenous placebo or big ET-1, in escalating dose (≤300 pmol/min). This increased plasma concentration and urinary excretion of ET-1. Big ET-1 reduced heart rate (≈8 beats/min) but did not otherwise affect systemic hemodynamics or glomerular filtration rate. Big ET-1 increased the fractional excretion of sodium (from 0.5 to 1.0%). It also increased free water clearance and tended to increase the abundance of the sodium–potassium–chloride cotransporter (NKCC2) in urinary extracellular vesicles. Our protocol induced modest increases in circulating and urinary ET-1. Sodium and water excretion increased in the absence of significant hemodynamic perturbation, supporting a direct action of ET-1 on the renal tubule. Our data also suggest that sodium reabsorption is stimulated by ET-1 in the thick ascending limb and suppressed in the distal renal tubule. Fluid retention associated with ET receptor antagonist therapy may be circumvented by coprescribing potassium-sparing diuretics. PMID:28507171

Potassium intake modulates the thiazide-sensitive sodium-chloride cotransporter (NCC) activity via the Kir4.1 potassium channel.

PubMed

Wang, Ming-Xiao; Cuevas, Catherina A; Su, Xiao-Tong; Wu, Peng; Gao, Zhong-Xiuzi; Lin, Dao-Hong; McCormick, James A; Yang, Chao-Ling; Wang, Wen-Hui; Ellison, David H

2018-04-01

Kir4.1 in the distal convoluted tubule plays a key role in sensing plasma potassium and in modulating the thiazide-sensitive sodium-chloride cotransporter (NCC). Here we tested whether dietary potassium intake modulates Kir4.1 and whether this is essential for mediating the effect of potassium diet on NCC. High potassium intake inhibited the basolateral 40 pS potassium channel (a Kir4.1/5.1 heterotetramer) in the distal convoluted tubule, decreased basolateral potassium conductance, and depolarized the distal convoluted tubule membrane in Kcnj10flox/flox mice, herein referred to as control mice. In contrast, low potassium intake activated Kir4.1, increased potassium currents, and hyperpolarized the distal convoluted tubule membrane. These effects of dietary potassium intake on the basolateral potassium conductance and membrane potential in the distal convoluted tubule were completely absent in inducible kidney-specific Kir4.1 knockout mice. Furthermore, high potassium intake decreased, whereas low potassium intake increased the abundance of NCC expression only in the control but not in kidney-specific Kir4.1 knockout mice. Renal clearance studies demonstrated that low potassium augmented, while high potassium diminished, hydrochlorothiazide-induced natriuresis in control mice. Disruption of Kir4.1 significantly increased basal urinary sodium excretion but it abolished the natriuretic effect of hydrochlorothiazide. Finally, hypokalemia and metabolic alkalosis in kidney-specific Kir4.1 knockout mice were exacerbated by potassium restriction and only partially corrected by a high-potassium diet. Thus, Kir4.1 plays an essential role in mediating the effect of dietary potassium intake on NCC activity and potassium homeostasis. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Dietary salt restriction is beneficial to the management of autosomal dominant polycystic kidney disease.

PubMed

Torres, Vicente E; Abebe, Kaleab Z; Schrier, Robert W; Perrone, Ronald D; Chapman, Arlene B; Yu, Alan S; Braun, William E; Steinman, Theodore I; Brosnahan, Godela; Hogan, Marie C; Rahbari, Frederic F; Grantham, Jared J; Bae, Kyongtae T; Moore, Charity G; Flessner, Michael F

2017-02-01

The CRISP study of polycystic kidney disease (PKD) found that urinary sodium excretion associated with the rate of total kidney volume increase. Whether sodium restriction slows the progression of Autosomal Dominant PKD (ADPKD) is not known. To evaluate this we conducted a post hoc analysis of the HALT-PKD clinical trials of renin-angiotensin blockade in patients with ADPKD. Linear mixed models examined whether dietary sodium affected rates of total kidney volume or change in estimated glomerular filtration rate (eGFR) in patients with an eGFR over 60 ml/min/1.73 m 2 (Study A) or the risk for a composite endpoint of 50% reduction in eGFR, end-stage renal disease or death, or the rate of eGFR decline in patients with an eGFR 25-60 ml/min/1.73 m 2 (Study B) all in patients initiated on an under100 mEq sodium diet. During the trial urinary sodium excretion significantly declined by an average of 0.25 and 0.41 mEq/24 hour per month in studies A and B, respectively. In Study A, averaged and time varying urinary sodium excretions were significantly associated with kidney growth (0.43%/year and 0.09%/year, respectively, for each 18 mEq urinary sodium excretion). Averaged urinary sodium excretion was not significantly associated with faster eGFR decline (-0.07 ml/min/1.73m 2 /year for each 18 mEq urinary sodium excretion). In Study B, the averaged but not time-varying urinary sodium excretion significantly associated with increased risk for the composite endpoint (hazard ratio 1.08 for each 18 mEq urinary sodium excretion) and a significantly faster eGFR decline (-0.09 ml/min/1.73m 2 /year for each mEq 18 mEq urinary sodium excretion). Thus, sodium restriction is beneficial in the management of ADPKD. Copyright © 2016 International Society of Nephrology. All rights reserved.

Validation and Assessment of Three Methods to Estimate 24-h Urinary Sodium Excretion from Spot Urine Samples in Chinese Adults

PubMed Central

Peng, Yaguang; Li, Wei; Wang, Yang; Chen, Hui; Bo, Jian; Wang, Xingyu; Liu, Lisheng

2016-01-01

24-h urinary sodium excretion is the gold standard for evaluating dietary sodium intake, but it is often not feasible in large epidemiological studies due to high participant burden and cost. Three methods—Kawasaki, INTERSALT, and Tanaka—have been proposed to estimate 24-h urinary sodium excretion from a spot urine sample, but these methods have not been validated in the general Chinese population. This aim of this study was to assess the validity of three methods for estimating 24-h urinary sodium excretion using spot urine samples against measured 24-h urinary sodium excretion in a Chinese sample population. Data are from a substudy of the Prospective Urban Rural Epidemiology (PURE) study that enrolled 120 participants aged 35 to 70 years and collected their morning fasting urine and 24-h urine specimens. Bias calculations (estimated values minus measured values) and Bland-Altman plots were used to assess the validity of the three estimation methods. 116 participants were included in the final analysis. Mean bias for the Kawasaki method was -740 mg/day (95% CI: -1219, 262 mg/day), and was the lowest among the three methods. Mean bias for the Tanaka method was -2305 mg/day (95% CI: -2735, 1875 mg/day). Mean bias for the INTERSALT method was -2797 mg/day (95% CI: -3245, 2349 mg/day), and was the highest of the three methods. Bland-Altman plots indicated that all three methods underestimated 24-h urinary sodium excretion. The Kawasaki, INTERSALT and Tanaka methods for estimation of 24-h urinary sodium excretion using spot urines all underestimated true 24-h urinary sodium excretion in this sample of Chinese adults. Among the three methods, the Kawasaki method was least biased, but was still relatively inaccurate. A more accurate method is needed to estimate the 24-h urinary sodium excretion from spot urine for assessment of dietary sodium intake in China. PMID:26895296

Determinants of Brushite Stone Formation: A Case-Control Study

PubMed Central

Siener, Roswitha; Netzer, Linda; Hesse, Albrecht

2013-01-01

Purpose The occurrence of brushite stones has increased during recent years. However, the pathogenic factors driving the development of brushite stones remain unclear. Methods Twenty-eight brushite stone formers and 28 age-, sex- and BMI-matched healthy individuals were enrolled in this case-control study. Anthropometric, clinical, 24 h urinary parameters and dietary intake from 7-day weighed food records were assessed. Results Pure brushite stones were present in 46% of patients, while calcium oxalate was the major secondary stone component. Urinary pH and oxalate excretion were significantly higher, whereas urinary citrate was lower in patients as compared to healthy controls. Despite lower dietary intake, urinary calcium excretion was significantly higher in brushite stone patients. Binary logistic regression analysis revealed pH>6.50 (OR 7.296; p = 0.035), calcium>6.40 mmol/24 h (OR 25.213; p = 0.001) and citrate excretion <2.600 mmol/24 h (OR 15.352; p = 0.005) as urinary risk factors for brushite stone formation. A total of 56% of patients exhibited distal renal tubular acidosis (dRTA). Urinary pH, calcium and citrate excretion did not significantly differ between patients with or without dRTA. Conclusions Hypercalciuria, a diminished citrate excretion and an elevated pH turned out to be the major urinary determinants of brushite stone formation. Interestingly, urinary phosphate was not associated with urolithiasis. The increased urinary oxalate excretion, possibly due to decreased calcium intake, promotes the risk of mixed stone formation with calcium oxalate. Neither dietary factors nor dRTA can account as cause for hypercalciuria, higher urinary pH and diminished citrate excretion. Further research is needed to define the role of dRTA in brushite stone formation and to evaluate the hypothesis of an acquired acidification defect. PMID:24265740

Mini-review: regulation of the renal NaCl cotransporter by hormones.

PubMed

Rojas-Vega, Lorena; Gamba, Gerardo

2016-01-01

The renal thiazide-sensitive NaCl cotransporter, NCC, is the major pathway for salt reabsorption in the distal convoluted tubule. The activity of this cotransporter is critical for regulation of several physiological variables such as blood pressure, serum potassium, acid base metabolism, and urinary calcium excretion. Therefore, it is not surprising that numerous hormone-signaling pathways regulate NCC activity to maintain homeostasis. In this review, we will provide an overview of the most recent evidence on NCC modulation by aldosterone, angiotensin II, vasopressin, glucocorticoids, insulin, norepinephrine, estradiol, progesterone, prolactin, and parathyroid hormone. Copyright © 2016 the American Physiological Society.

Body mass index predicts aldosterone production in normotensive adults on a high-salt diet.

PubMed

Bentley-Lewis, Rhonda; Adler, Gail K; Perlstein, Todd; Seely, Ellen W; Hopkins, Paul N; Williams, Gordon H; Garg, Rajesh

2007-11-01

The mechanisms underlying obesity-mediated cardiovascular disease are not fully understood. Aldosterone and insulin resistance both are associated with obesity and cardiovascular disease. The objectives of this study were to test the hypotheses that aldosterone production is elevated and associated with insulin resistance in overweight adults on a high-sodium diet. Healthy normotensive adults were categorized as lean body mass index (BMI) less than 25 kg/m(2) (n = 63) or overweight BMI 25 kg/m(2) or greater (n = 57). After 7 d of a high-sodium diet, participants fasted overnight and remained supine throughout hemodynamic and laboratory assessments and angiotensin II (AngII) stimulation. The overweight group, compared with the lean group, had higher 24-h urinary aldosterone (9.0 +/- 0.8 vs. 6.6 +/- 0.5 microg per 24 h; P = 0.003) and higher AngII-stimulated serum aldosterone (11.4 +/- 1.0 vs. 9.0 +/- 0.6 ng/dl; P = 0.04). There were no differences in 24-h urinary cortisol or sodium or supine measurements of plasma renin activity, serum aldosterone, or serum potassium. The homeostasis model assessment of insulin resistance was predicted by urinary aldosterone excretion (r = 0.32, P = 0.03) and serum aldosterone response to AngII stimulation (r = 0.28, P = 0.02) independent of age and BMI. Urinary aldosterone excretion and AngII-stimulated aldosterone are increased in overweight, compared with lean, normotensive adults. The correlation of these measures of aldosterone production with insulin resistance suggests a potential role for aldosterone in the pathophysiology of obesity-mediated insulin resistance.

Urinary excretion of platinum from South African precious metals refinery workers.

PubMed

Linde, Stephanus J L; Franken, Anja; du Plessis, Johannes L

2018-03-30

Urinary platinum (Pt) excretion is a reliable biomarker for occupational Pt exposure and has been previously reported for precious metals refinery workers in Europe but not for South Africa, the world's largest producer of Pt. This study aimed to quantify the urinary Pt excretion of South African precious metals refinery workers. Spot urine samples were collected from 40 workers (directly and indirectly exposed to Pt) at two South African precious metals refineries on three consecutive mornings prior to their shifts. Urine samples were analysed for Pt using inductively coupled plasma-mass spectrometry and were corrected for creatinine content. The urinary Pt excretion of workers did not differ significantly between sampling days. Urinary Pt excretions ranged from <0.1 to 3.0 µg Pt/g creatinine with a geometric mean of 0.21 µg Pt/g creatinine (95% CI 0.17 to 0.26 µg Pt/g creatinine). The work area (P=0.0006; η 2 =0.567) and the number of years workers were employed at the refineries (P=0.003; η 2 =0.261) influenced their urinary Pt excretion according to effect size analyses. Directly exposed workers had significantly higher urinary Pt excretion compared with indirectly exposed workers (P=0.007). The urinary Pt excretion of South African precious metals refinery workers reported in this study is comparable with that of seven other studies conducted in precious metals refineries and automotive catalyst plants in Europe. The Pt body burden of workers is predominantly determined by their work area, years of employment in the refineries and whether they are directly or indirectly exposed to Pt. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Radioactive iodide (131 I-) excretion profiles in response to potassium iodide (KI) and ammonium perchlorate (NH4ClO4) prophylaxis.

PubMed

Harris, Curtis; Dallas, Cham; Rollor, Edward; White, Catherine; Blount, Benjamin; Valentin-Blasini, Liza; Fisher, Jeffrey

2012-08-01

Radioactive iodide ((131)I-) protection studies have focused primarily on the thyroid gland and disturbances in the hypothalamic-pituitary-thyroid axis. The objective of the current study was to establish (131)I- urinary excretion profiles for saline, and the thyroid protectants, potassium iodide (KI) and ammonium perchlorate over a 75 hour time-course. Rats were administered (131)I- and 3 hours later dosed with either saline, 30 mg/kg of NH(4)ClO(4) or 30 mg/kg of KI. Urinalysis of the first 36 hours of the time-course revealed that NH(4)ClO(4) treated animals excreted significantly more (131)I- compared with KI and saline treatments. A second study followed the same protocol, but thyroxine (T(4)) was administered daily over a 3 day period. During the first 6-12 hour after (131)I- dosing, rats administered NH(4)ClO(4) excreted significantly more (131)I- than the other treatment groups. T(4) treatment resulted in increased retention of radioiodide in the thyroid gland 75 hour after (131)I- administration. We speculate that the T(4) treatment related reduction in serum TSH caused a decrease synthesis and secretion of thyroid hormones resulting in greater residual radioiodide in the thyroid gland. Our findings suggest that ammonium perchlorate treatment accelerates the elimination rate of radioiodide within the first 24 to 36 hours and thus may be more effective at reducing harmful exposure to (131)I- compared to KI treatment for repeated dosing situations. Repeated dosing studies are needed to compare the effectiveness of these treatments to reduce the radioactive iodide burden of the thyroid gland.

Effects of cooking using multi-ply cookware on absorption of potassium and vitamins: a randomized double-blind placebo control study.

PubMed

Mori, Mari; Hamada, Atsumi; Mori, Hideki; Yamori, Yukio; Tsuda, Kinsuke

2012-08-01

This 2-week interventional study involved a randomized allocation of subjects into three groups: Group A (daily ingestion of 350 g vegetables cooked without water using multi-ply [multilayer-structured] cookware), Group B (daily ingestion of 350 g vegetables; ordinary cookware) and Group C (routine living). Before and after intervention, each subject underwent health examination with 24-h urine sampling. Blood vitamin C significantly increased after intervention from the baseline in Group A (P < 0.01) and Group B (P < 0.05). β-Carotene levels also increased significantly after intervention in Group A (P < 0.01) and Group B (P < 0.01). Oxidized low-density lipoprotein decreased significantly after intervention in Group A (P < 0.01). In Group A, 24-h urinary potassium excretion increased significantly (P < 0.01) and 24-h urinary sodium (Na)/K ratio improved significantly (P < 0.05) after intervention. In conclusion, a cooking method modification with multi-ply cookware improved absorption of nutrients from vegetables and enhanced effective utilization of the antioxidant potentials of vegetable nutrients.

Urinary renin, but not angiotensinogen or aldosterone, reflects the renal renin-angiotensin-aldosterone system activity and the efficacy of renin-angiotensin-aldosterone system blockade in the kidney.

PubMed

van den Heuvel, Mieke; Batenburg, Wendy W; Jainandunsing, Sjaam; Garrelds, Ingrid M; van Gool, Jeanette M G; Feelders, Richard A; van den Meiracker, Anton H; Danser, A H Jan

2011-11-01

To study which renin-angiotensin-aldosterone system (RAAS) component best reflects renal RAAS activity. We measured urinary and plasma renin, prorenin, angiotensinogen, aldosterone, albumin and creatinine in 101 diabetic and nondiabetic patients with or without hypertension. Plasma prorenin was elevated in diabetic patients. Urinary prorenin was undetectable. Urinary albumin and renin were higher in diabetic patients. Men had higher plasma renin/prorenin levels, and lower plasma angiotensinogen levels than women. Plasma creatinine and albumin were also higher in men. Urinary RAAS components showed no sexual dimorphism, whereas urinary creatinine and albumin were higher in men. Angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor blockers increased plasma renin and decreased plasma angiotensinogen, without altering plasma aldosterone. In contrast, in urine, these drugs decreased renin and aldosterone without affecting angiotensinogen. When analyzing all patients together, urinary angiotensinogen excretion closely mimicked that of albumin, whereas urinary angiotensinogen and albumin levels both were 0.05% or less of their concomitant plasma levels. This may reflect the identical glomerular filtration and tubular handling of both proteins, which have a comparable molecular weight. In contrast, urinary renin excretion did not correlate with urinary albumin excretion, and the urinary/plasma concentration ratio of renin was more than 200 times the ratio of albumin, despite its comparable molecular weight. Urinary aldosterone excretion closely followed urinary creatinine excretion. The increased urinary renin levels in diabetes and the decreased urinary renin levels following RAAS blockade, occurring independently of changes in plasma renin, reflect the activated renal RAAS in diabetes and the success of RAAS blockade in the kidney, respectively. Urinary renin, therefore, more closely reflects renal RAAS activity than urinary angiotensinogen or aldosterone.

An association between urinary cadmium and urinary stone disease in persons living in cadmium-contaminated villages in northwestern Thailand: A population study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swaddiwudhipong, Witaya, E-mail: swaddi@hotmail.com; Mahasakpan, Pranee; Limpatanachote, Pisit

Excessive urinary calcium excretion is the major risk of urinary stone formation. Very few population studies have been performed to determine the relationship between environmental cadmium exposure and urinary stone disease. This population-based study examined an association between urinary cadmium excretion, a good biomarker of long-term cadmium exposure, and prevalence of urinary stones in persons aged 15 years and older, who lived in the 12 cadmium-contaminated villages in the Mae Sot District, Tak Province, northwestern Thailand. A total of 6748 persons were interviewed and screened for urinary cadmium and urinary stone disease in 2009. To test a correlation between urinarymore » excretion of cadmium and calcium, we measured urinary calcium content in 1492 persons, who lived in 3 villages randomly selected from the 12 contaminated villages. The rate of urinary stones significantly increased from 4.3% among persons in the lowest quartile of urinary cadmium to 11.3% in the highest quartile. An increase in stone prevalence with increasing urinary cadmium levels was similarly observed in both genders. Multiple logistic regression analysis revealed a positive association between urinary cadmium levels and stone prevalence, after adjusting for other co-variables. The urinary calcium excretion significantly increased with increasing urinary cadmium levels in both genders, after adjusting for other co-variables. Elevated calciuria induced by cadmium might increase the risk of urinary stone formation in this environmentally exposed population. - Research highlights: {yields} Excessive calciuria is the major risk of urinary stone formation. {yields} We examine cadmium-exposed persons for urinary cadmium, calcium, and stones. {yields} The rate of urinary stones increases with increasing urinary cadmium. {yields} Urinary calcium excretion increases with increasing urinary cadmium. {yields} Elevated calciuria induced by cadmium may increase the risk of urinary stones.« less

Pathophysiology of Intense Physical Conditioning in a Hot Climate. I. MECHANISMS OF POTASSIUM DEPLETION

PubMed Central

Knochel, James P.; Dotin, Larry N.; Hamburger, Richard J.

1972-01-01

Serial estimations of exchangeable 42K showed that six volunteer subjects undergoing intensive physical conditioning in a hot climate sustained a mean deficit of 517 mEq. This deficit occurred despite a daily potassium intake of 100 mEq. Simultaneous values for lean body mass rose suggesting that potassium deficiency was not the result of catabolism. Although sweating was the major avenue by which the deficit occurred, daily excretion of potassium into the urine when each subject was maximally deficient ranged from 46 to 75 mEq and thus was inappropriately high for potassium-depleted subjects. Despite high intakes of sodium and excretion of corresponding quantities into the urine, Na/K ratios in sweat were low thus indicating unsuppressed activity of aldosterone on sweat glands. Moreover, excretion and secretion of aldosterone and in many instances, plasma renin activity, appeared to be high with respect to sodium intake. These findings suggest that intense physical work in the heat stimulates higher production of aldosterone than would occur in nonexercising subjects on similar sodium intakes. Similar to the phenomenon of mineralocorticoid escape, such overproduction of aldosterone in the presence of conditions permitting excretion of sodium into the urine could facilitate continued excretion of potassium by the kidney despite serious potassium depletion. As a consequence, the kidney played a role in the genesis of potassium depletion in these subjects. In contrast to subjects undergoing conditioning in the summer months, potassium depletion did not occur in 16 subjects during identical training under cooler environmental conditions. Images PMID:5009112

Objective assessment of smoking habits by urinary cotinine measurement in adolescents and young adults with type 1 diabetes. Reliability of reported cigarette consumption and relationship to urinary albumin excretion.

PubMed

Holl, R W; Grabert, M; Heinze, E; Debatin, K M

1998-05-01

To examine the relationship of objective smoking status to age, sex, longterm metabolic control, and urinary albumin excretion. Patients with type 1 diabetes who smoke are at increased risk to develop diabetic microvascular and macrovascular complications. While this has repeatedly been demonstrated in adults, smoking habits have rarely been investigated in adolescents. Urinary continine excretion has been determined by radioimmunoassay in 238 adolescents and young adults with type 1 diabetes. This biochemical parameter of nicotine use was related to age, to the number of cigarettes allegedly consumed per day, and to urinary albumin excretion. A total of 46 patients (19.3%) with urinary cotinine values > 500 ng/ml were classified as smokers. In 26 patients (10.9%), cotinine values between 100 and 500 ng/ml were found (infrequent smokers or environmental nicotine exposure), while the remaining 166 patients excreted < 100 ng/ml of cotinine in the urine (nonsmokers). Smokers were significantly older (20.2 +/- 0.6 years [mean +/- SE]) compared with the intermediate group (18.3 +/- 0.7 years) or with nonsmokers (15.9 +/- 0.4 years; P < 0.0001, Wilcoxon's signed-rank test). Of 46 smokers, 12 denied smoking cigarettes entirely, and among biochemically defined smokers, no correlation was present between urinary continine excretion and the reported number of cigarettes consumed per day. Urinary albumin excretion was significantly higher in smokers compared with nonsmokers (P < 0.003). These data demonstrate that cigarette smoking is common among German adolescents and young adults with type 1 diabetes in this study. Many patients deny nicotine use or refuse to disclose their smoking habits. Increased urinary albumin excretion is consistent with an increased risk of nephropathy in subjects with diabetes who smoke. Pediatricians in charge of adolescents with type 1 diabetes should actively discuss the risk of nicotine consumption with their patients.

Effect of potential renal acid load of foods on urinary citrate excretion in calcium renal stone formers.

PubMed

Trinchieri, Alberto; Lizzano, Renata; Marchesotti, Federica; Zanetti, Giampaolo

2006-02-01

The aim of this study was to investigate the influence of the potential renal acid load (PRAL) of the diet on the urinary risk factors for renal stone formation. The present series comprises 187 consecutive renal calcium stone patients (114 males, 73 females) who were studied in our stone clinic. Each patient was subjected to an investigation including a 24-h dietary record and 24-h urine sample taken over the same period. Nutrients and calories were calculated by means of food composition tables using a computerized procedure. Daily PRAL was calculated considering the mineral and protein composition of foods, the mean intestinal absorption rate for each nutrient and the metabolism of sulfur-containing amino acids. Sodium, potassium, calcium, magnesium, phosphate, oxalate, urate, citrate, and creatinine levels were measured in the urine. The mean daily PRAL was higher in male than in female patients (24.1+/-24.0 vs 16.1+/-20.1 mEq/day, P=0.000). A significantly (P=0.01) negative correlation (R=-0.18) was found between daily PRAL and daily urinary citrate, but no correlation between PRAL and urinary calcium, oxalate, and urate was shown. Daily urinary calcium (R=0.186, P=0.011) and uric acid (R=0.157, P=0.033) were significantly related to the dietary intake of protein. Daily urinary citrate was significantly related to the intakes of copper (R=0.178, P=0.015), riboflavin (R=0.20, P=0.006), piridoxine (R=0.169, P=0.021) and biotin (R=0.196, P=0.007). The regression analysis by stepwise selection confirmed the significant negative correlation between PRAL and urinary citrate (P=0.002) and the significant positive correlation between riboflavin and urinary citrate (P=0.000). Urinary citrate excretion of renal stone formers (RSFs) is highly dependent from dietary acid load. The computation of the renal acid load is advisable to investigate the role of diet in the pathogenesis of calcium stone disease and it is also a useful tool to evaluate the lithogenic potential of the diet of the individual patient.

The urinary excretion of metformin, ceftizoxime and ofloxacin in high serum creatinine rats: Can creatinine predict renal tubular elimination?

PubMed

Ma, Yan-Rong; Zhou, Yan; Huang, Jing; Qin, Hong-Yan; Wang, Pei; Wu, Xin-An

2018-03-01

The renal excretion of creatinine and most drugs are the net result of glomerular filtration and tubular secretion, and their tubular secretions are mediated by individual transporters. Thus, we hypothesized that the increase of serum creatinine (SCr) levels attributing to inhibiting tubular transporters but not glomerular filtration rate (GFR) could be used to evaluate the tubular excretion of drugs mediated by identical or partial overlap transporter with creatinine. In this work, we firstly developed the creatinine excretion inhibition model with normal GFR by competitively inhibiting tubular transporters, and investigated the renal excretion of metformin, ceftizoxime and ofloxacin in vivo and in vitro. The results showed that the 24-hour urinary excretion of metformin and ceftizoxime in model rats were decreased by 25% and 17% compared to that in control rats, respectively. The uptake amount and urinary excretion of metformin and ceftizoxime could be inhibited by creatinine in renal cortical slices and isolated kidney perfusion. However, the urinary excretion of ofloxacin was not affected by high SCr. These results showed that the inhibition of tubular creatinine transporters by high SCr resulted to the decrease of urinary excretion of metformin and ceftizoxime, but not ofloxacin, which implied that the increase of SCr could also be used to evaluate the tubular excretion of drugs mediated by identical or partial overlap transporter with creatinine in normal GFR rats. Copyright © 2018 Elsevier Inc. All rights reserved.

Genetic African Ancestry and Markers of Mineral Metabolism in CKD

PubMed Central

Parsa, Afshin; Isakova, Tamara; Scialla, Julia J.; Chen, Jing; Flack, John M.; Nessel, Lisa C.; Gupta, Jayanta; Bellovich, Keith A.; Steigerwalt, Susan; Sondheimer, James H.; Wright, Jackson T.; Feldman, Harold I.; Kusek, John W.; Lash, James P.; Wolf, Myles

2016-01-01

Background and objectives Disorders of mineral metabolism are more common in African Americans with CKD than in European Americans with CKD. Previous studies have focused on the differences in mineral metabolism by self-reported race, making it difficult to delineate the importance of environmental compared with biologic factors. Design, setting, participants, & measurements In a cross-sectional analysis of 3013 participants of the Chronic Renal Insufficiency Cohort study with complete data, we compared markers of mineral metabolism (phosphorus, calcium, alkaline phosphatase, parathyroid hormone, fibroblast growth factor 23, and urine calcium and phosphorus excretion) in European Americans versus African Americans and separately, across quartiles of genetic African ancestry in African Americans (n=1490). Results Compared with European Americans, African Americans had higher blood concentrations of phosphorus, alkaline phosphatase, fibroblast growth factor 23, and parathyroid hormone, lower 24-hour urinary excretion of calcium and phosphorus, and lower urinary fractional excretion of calcium and phosphorus at baseline (P<0.001 for all). Among African Americans, a higher percentage of African ancestry was associated with lower 24-hour urinary excretion of phosphorus (Ptrend<0.01) in unadjusted analyses. In linear regression models adjusted for socio-demographic characteristics, kidney function, serum phosphorus, and dietary phosphorus intake, higher percentage of African ancestry was significantly associated with lower 24-hour urinary phosphorus excretion (each 10% higher African ancestry was associated with 39.6 mg lower 24-hour urinary phosphorus, P<0.001) and fractional excretion of phosphorus (each 10% higher African ancestry was associated with an absolute 1.1% lower fractional excretion of phosphorus, P=0.01). Conclusions A higher percentage of African ancestry was independently associated with lower 24-hour urinary phosphorus excretion and lower fractional excretion of phosphorus among African Americans with CKD. These findings suggest that genetic variability might contribute to racial differences in urinary phosphorus excretion in CKD. PMID:26912553

Genetic African Ancestry and Markers of Mineral Metabolism in CKD.

PubMed

Gutiérrez, Orlando M; Parsa, Afshin; Isakova, Tamara; Scialla, Julia J; Chen, Jing; Flack, John M; Nessel, Lisa C; Gupta, Jayanta; Bellovich, Keith A; Steigerwalt, Susan; Sondheimer, James H; Wright, Jackson T; Feldman, Harold I; Kusek, John W; Lash, James P; Wolf, Myles

2016-04-07

Disorders of mineral metabolism are more common in African Americans with CKD than in European Americans with CKD. Previous studies have focused on the differences in mineral metabolism by self-reported race, making it difficult to delineate the importance of environmental compared with biologic factors. In a cross-sectional analysis of 3013 participants of the Chronic Renal Insufficiency Cohort study with complete data, we compared markers of mineral metabolism (phosphorus, calcium, alkaline phosphatase, parathyroid hormone, fibroblast growth factor 23, and urine calcium and phosphorus excretion) in European Americans versus African Americans and separately, across quartiles of genetic African ancestry in African Americans (n=1490). Compared with European Americans, African Americans had higher blood concentrations of phosphorus, alkaline phosphatase, fibroblast growth factor 23, and parathyroid hormone, lower 24-hour urinary excretion of calcium and phosphorus, and lower urinary fractional excretion of calcium and phosphorus at baseline (P<0.001 for all). Among African Americans, a higher percentage of African ancestry was associated with lower 24-hour urinary excretion of phosphorus (Ptrend<0.01) in unadjusted analyses. In linear regression models adjusted for socio-demographic characteristics, kidney function, serum phosphorus, and dietary phosphorus intake, higher percentage of African ancestry was significantly associated with lower 24-hour urinary phosphorus excretion (each 10% higher African ancestry was associated with 39.6 mg lower 24-hour urinary phosphorus, P<0.001) and fractional excretion of phosphorus (each 10% higher African ancestry was associated with an absolute 1.1% lower fractional excretion of phosphorus, P=0.01). A higher percentage of African ancestry was independently associated with lower 24-hour urinary phosphorus excretion and lower fractional excretion of phosphorus among African Americans with CKD. These findings suggest that genetic variability might contribute to racial differences in urinary phosphorus excretion in CKD. Copyright © 2016 by the American Society of Nephrology.

Effects of Different Doses of Irbesartan Combined With Spironolactone on Urinary Albumin Excretion Rate in Elderly Patients With Early Type 2 Diabetic Nephropathy.

PubMed

Chen, Yingying; Liu, Peng; Chen, Xia; Li, Yanan; Zhang, Fengmei; Wang, Yangang

2018-05-01

There is a lack of research on the effect of low dose of angiotensin receptor blockers combined with spironolactone, and the effect of high dose of angiotensin receptor blockers alone on the urinary albumin excretion rate (UAER) in elderly patients with early type 2 diabetic nephropathy (DN). We conducted a prospective, randomized, open-label, parallel-controlled study that included 244 elderly patients with early DN and mild-to-moderate essential hypertension. Patients were randomly divided into 4 groups: low-dose irbesartan (group A), high-dose irbesartan (group B), low-dose irbesartan combined with spironolactone (group C) and high-dose irbesartan combined with spironolactone (group D). Changes in UAER, serum potassium and blood pressure were compared. There were no statistical differences in the baseline characteristics among groups. Furthermore, no significant difference in blood pressure before and after treatment was found among different groups. After 72-week treatment, UAER in group D was lower compared to group A and B (P < 0.05). Meanwhile, compared with group B, UAER in group C decreased significantly (P < 0.05). Additionally, significantly higher serum potassium was found in group D compared to other groups (P < 0.05). Also, group D had the highest count of patients who withdrew from the study due to hyperkalemia compared to other groups (P < 0.05). Our results indicate high-dose irbesartan combined with spironolactone may be more efficient in reducing UAER in elderly patients with early DN, but this treatment could cause hyperkalemia. Low-dose irbesartan combined with spironolactone was shown to be safer and more effective in decreasing UAER compared to high-dose irbesartan. Copyright © 2018 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

Urinary protein-to-creatinine ratio versus 24-h proteinuria in the screening for nephropathy in HIV patients.

PubMed

Antonello, Vicente Sperb; Poli-De-Figueiredo, Carlos Eduardo; Antonello, Ivan Carlos Ferreira; Tovo, Cristiane Valle

2015-06-01

To determine the correlation between protein-to-creatinine ratio and 24-h urinary protein, proteinuria was measured in 45 patients attending a public HIV clinic in Porto Alegre, Brazil, using 24-h urinary protein excretion (24hUP) and urinary protein-to-creatinine ratio. Spearman's correlation test was done to evaluate the association between spot protein-to-creatinine ratio and 24hUP. The limits of agreement between the two methods were analysed by the Bland-Altman method. For protein excretion <1 g/day, limits (95%) of agreement of protein-to-creatinine ratio and 24hUP were +0.112 and -0.097 g/day. A strong correlation (r = 0.957) was found between protein-to-creatinine ratio and 24hUP excretion. The conclusion is that the protein-to-creatinine ratio in spot urine specimens is an accurate, convenient and reliable screening method to estimate the urinary protein excretion in HIV patients to detect abnormal urinary protein loss. Further studies are required to evaluate renal disease in HIV patients with chronic renal disease and higher urinary protein excretion. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Advances in the management of hyperkalemia in chronic kidney disease.

PubMed

Cowan, Andrea C J; Gharib, Elie G; Weir, Matthew A

2017-05-01

Patients with chronic kidney disease (CKD) have an increased risk of hyperkalemia that increases both short-term and long-term mortality. Historically, managing hyperkalemia has relied upon dietary modifications, augmentation of urinary potassium excretion and enhanced enteral potassium elimination. This review discusses current treatments and their limitations and summarizes the evidence supporting novel agents for potassium lowering in patients with CKD. The introduction of two novel ion exchange resins represents the first new pharmacologic therapies for hyperkalemia in the last 50 years. Patiromer, which was recently approved for use in the United States, has been shown to be well tolerated and effective for decreasing serum potassium in patients with CKD when taken for up to a year. Sodium zirconium cyclosilicate for which approval is pending has also shown promise in treating both acute and chronic hyperkalemia in patients with CKD. Both medications have been well tolerated with minimal adverse events in relatively short-term follow-up. Novel ion exchange resins have the potential to provide new strategies for safely and effectively managing hyperkalemia in the CKD population. This may decrease morbidity and mortality associated with hyperkalemia and allow more broad use of medications whose use is otherwise limited by hyperkalemia.

Decrease in Urinary Creatinine Excretion in Early Stage Chronic Kidney Disease

PubMed Central

Tynkevich, Elena; Flamant, Martin; Haymann, Jean-Philippe; Metzger, Marie; Thervet, Eric; Boffa, Jean-Jacques; Vrtovsnik, François; Houillier, Pascal; Froissart, Marc; Stengel, Bénédicte

2014-01-01

Background Little is known about muscle mass loss in early stage chronic kidney disease (CKD). We used 24-hour urinary creatinine excretion rate to assess determinants of muscle mass and its evolution with kidney function decline. We also described the range of urinary creatinine concentration in this population. Methods We included 1072 men and 537 women with non-dialysis CKD stages 1 to 5, all of them with repeated measurements of glomerular filtration rate (mGFR) by 51Cr-EDTA renal clearance and several nutritional markers. In those with stage 1 to 4 at baseline, we used a mixed model to study factors associated with urinary creatinine excretion rate and its change over time. Results Baseline mean urinary creatinine excretion decreased from 15.3±3.1 to 12.1±3.3 mmol/24 h (0.20±0.03 to 0.15±0.04 mmol/kg/24 h) in men, with mGFR falling from ≥60 to <15 mL/min/1.73 m2, and from 9.6±1.9 to 7.6±2.5 (0.16±0.03 to 0.12±0.03) in women. In addition to mGFR, an older age, diabetes, and lower levels of body mass index, proteinuria, and protein intake assessed by urinary urea were associated with lower mean urinary creatinine excretion at baseline. Mean annual decline in mGFR was 1.53±0.12 mL/min/1.73 m2 per year and that of urinary creatinine excretion rate, 0.28±0.02 mmol/24 h per year. Patients with fast annual decline in mGFR of 5 mL/min/1.73 m2 had a decrease in urinary creatinine excretion more than twice as big as in those with stable mGFR, independent of changes in urinary urea as well as of other determinants of low muscle mass. Conclusions Decrease in 24-hour urinary creatinine excretion rate may appear early in CKD patients, and is greater the more mGFR declines independent of lowering protein intake assessed by 24-hour urinary urea. Normalizing urine analytes for creatininuria may overestimate their concentration in patients with reduced kidney function and low muscle mass. PMID:25401694

Dietary sodium and potassium intake were associated with hypertension, kidney damage and adverse perinatal outcome in pregnant women with preeclampsia.

PubMed

Yılmaz, Zehra Vural; Akkaş, Elif; Türkmen, Gülenay Gençosmanoğlu; Kara, Özgür; Yücel, Aykan; Uygur, Dilek

2017-02-01

In this study, we hypothesized that dietary salt and potassium intake may be related with blood pressure, kidney damage and perinatal outcome in pregnants with preeclampsia (PE). In total, 200 women (50 control women with healthy pregnancy, 150 women with PE) were recruited for the study. Daily salt and potassium intake was estimated based on calculation of 24-hour urinary sodium U[Na+] and potassium U[K+] excretion. U[Na+]/[K+] was calculated by dividing U[Na+] by U[K+]. At the end of the measurements, the pregnant women with PE (n=150) were divided into tertiles according to U[Na+]/[K+]: low Na/K group (n=50, mean U[Na+]/[K+]: 1,04±0,32), medium Na/K group (n=50, mean U[Na+]/[K+]: 2,49± 0,54), high Na/K group (n=50, mean U[Na+]/[K+]: 6,62±3,41). The mean SBP and DBP levels were significantly lower in low Na/K group compared with medium or high Na/K groups (p=0.024, p=0.0002; respectively). Serum creatinine was significantly lower in low Na/K group than high Na/K group (p=0.025). Frequency of severe preeclampsia is lower in low Na/K group than medium or high Na/K groups (p=0.002, p=0.0001; respectively). Birth weight and gestational age at birth were higher in low Na/K group compared with high Na/K group (p=0.045, p=0.0002; respectively). After adjusting for covariates, SBP and DBP and creatinine levels were independently associated with 24 hours urinary [Na+]/[K+] Conclusion: These findings suggest that pregnant with PE with high dietary salt and low potassium intake may have greater maternal and neonatal morbidity risk than pregnant with PE under low dietary salt and high potassium intake.

Intake and urinary excretion of sodium chloride under varying conditions of effort and environment heat

NASA Technical Reports Server (NTRS)

Zohar, E.; Adar, R.; Tennenbaum, J.; Kesten, M.

1982-01-01

Intake and urinary excretion of sodium were investigated in a group of young, healthy and acclimated men. The sodium excretions of workers and of machinists in the engine rooms of a ship were also investigated.

Physicochemical action of potassium-magnesium citrate in nephrolithiasis

NASA Technical Reports Server (NTRS)

Pak, C. Y.; Koenig, K.; Khan, R.; Haynes, S.; Padalino, P.

1992-01-01

Effect of potassium-magnesium citrate on urinary biochemistry and crystallization of stone-forming salts was compared with that of potassium citrate at same dose of potassium in five normal subjects and five patients with calcium nephrolithiasis. Compared to the placebo phase, urinary pH rose significantly from 6.06 +/- 0.27 to 6.48 +/- 0.36 (mean +/- SD, p less than 0.0167) during treatment with potassium citrate (50 mEq/day for 7 days) and to 6.68 +/- 0.31 during therapy with potassium-magnesium citrate (containing 49 mEq K, 24.5 mEq Mg, and 73.5 mEq citrate per day). Urinary pH was significantly higher during potassium-magnesium citrate than during potassium citrate therapy. Thus, the amount of undissociated uric acid declined from 118 +/- 61 mg/day during the placebo phase to 68 +/- 54 mg/day during potassium citrate treatment and, more prominently, to 41 +/- 46 mg/day during potassium-magnesium citrate therapy. Urinary magnesium rose significantly from 102 +/- 25 to 146 +/- 37 mg/day during potassium-magnesium citrate therapy but not during potassium citrate therapy. Urinary citrate rose more prominently during potassium-magnesium citrate therapy (to 1027 +/- 478 mg/day from 638 +/- 252 mg/day) than during potassium citrate treatment (to 932 +/- 297 mg/day). Consequently, urinary saturation (activity product) of calcium oxalate declined significantly (from 1.49 x 10(-8) to 1.03 x 10(-8) M2) during potassium-magnesium citrate therapy and marginally (to 1.14 x 10(-8) M2) during potassium citrate therapy.(ABSTRACT TRUNCATED AT 250 WORDS).

Factors Affecting Canagliflozin-Induced Transient Urine Volume Increase in Patients with Type 2 Diabetes Mellitus.

PubMed

Tanaka, Hiroyuki; Takano, Kazuhiko; Iijima, Hiroaki; Kubo, Hajime; Maruyama, Nobuko; Hashimoto, Toshio; Arakawa, Kenji; Togo, Masanori; Inagaki, Nobuya; Kaku, Kohei

2017-02-01

Sodium glucose co-transporter 2 (SGLT2) inhibitors exhibit diuretic activity, which is a possible mechanism underlying the cardiovascular benefit of these inhibitors. However, the osmotic diuresis-induced increase in urine volume, and the risk of dehydration have been of concern with SGLT2 inhibitor treatment. This study aimed to investigate the mechanism underlying SGLT2 inhibitor canagliflozin-induced diuresis in Japanese type 2 diabetes mellitus (T2DM) patients. Thirteen T2DM patients received a daily oral dose of 100 mg canagliflozin before breakfast for 6 days. Blood and urine samples were collected at predetermined time points. The primary endpoint was evaluation of correlations between changes from baseline in urine volume and factors that are known to affect urine volume and between actual urine volume and these factors. Canagliflozin transiently increased urine volume and urinary sodium excretion on Day 1 with a return to baseline levels thereafter. Canagliflozin administration increased urinary glucose excretion, which was sustained during repeated-dose administration. Plasma atrial natriuretic peptide (ANP) and N-terminal pro-b-type natriuretic peptide (NT-proBNP) levels decreased, while plasma renin activity increased. On Day 1 of treatment, changes in sodium and potassium excretion were closely correlated with changes in urine output. A post hoc multiple regression analysis showed changes in sodium excretion and water intake as factors that affected urine volume change at Day 1. Furthermore, relative to that at baseline, canagliflozin decreased blood glucose throughout the day and increased plasma total GLP-1 after breakfast. Canagliflozin induced transient sodium excretion and did not induce water intake at Day 1; hence, natriuresis rather than glucose-induced osmotic diuresis may be a major factor involved in the canagliflozin-induced transient increase in urine output. In addition, canagliflozin decreased plasma ANP and NT-proBNP levels and increased plasma renin activity, which may be a compensatory mechanism for sodium retention, leading to subsequent urine output recovery. UMIN000019462. Mitsubishi Tanabe Pharma Corporation.

Vasopressin and oxytocin levels during normal pregnancy: effects of chronic dietary sodium restriction.

PubMed

van der Post, J A; van Buul, B J; Hart, A A; van Heerikhuize, J J; Pesman, G; Legros, J J; Steegers, E A; Swaab, D F; Boer, K

1997-03-01

Neurohypophysial hormones are thought to be involved in alterations in fluid balance during pregnancy and delivery. In the course of normal pregnancy intravascular volume is increased whereas sodium restriction is thought to reduce plasma volume and cardiac output. In the present study, we measured the effect of long-term severe sodium restriction on vasopressin (AVP) and oxytocin (OT) levels during normal pregnancy and after delivery. Fifty-nine healthy nulliparous women were randomized either for a low sodium diet (20 mmol sodium daily) or for a normal diet from week 12 of pregnancy onwards. Circulating plasma levels and urinary excretion of AVP and OT, their neurophysins (Np-AVP and Np-OT) and AVP bound to platelets were determined at regular intervals during pregnancy and after delivery. After completion of the study, women on a sodium-restricted diet were compared with control women on a normal diet using repeated measurement ANOVA with adjustment for potentially confounding variables. After randomization, a reduction in urinary sodium excretion of, on average, 40-82% was found. In general, no effect of sodium restriction could be demonstrated on the various parameters (0.53 < P < 0.98) with the exception of a significantly lower 24-h urinary AVP excretion by non-smokers with sodium restriction compared with non-smokers having a normal diet (P = 0.018). For all parameters, clear changes were found in the course of pregnancy and puerperium (P < 0.0001 to P < 0.005). Platelet-bound AVP decreased and Np-OT increased during pregnancy. After birth, free plasma AVP, platelet-bound AVP, OT, osmolality, sodium and potassium increased, while Np-AVP and Np-OT decreased. Although elevated Np-AVP and Np-OT levels during pregnancy seem to indicate increased release of neurohypophysial hormones, pregnancy up to 36 weeks of gestation is accompanied by low circulating AVP and OT levels. Long-term severe sodium restriction diminishes urinary AVP excretion in (non-smoking) pregnant women, without changing circulating levels of AVP and OT, despite the known reduction in circulating volume. The reduced circulating (platelet-bound) AVP levels during pregnancy, whether or not in combination with severe sodium restriction, support the absence of significant non-osmotic stimulation of AVP during pregnancy.

Raised urinary glucocorticoid and adrenal androgen precursors in the urine of young hypertensive patients: possible evidence for partial glucocorticoid resistance

PubMed Central

Shamim, W; Yousufuddin, M; Francis, D; Gualdiero, P; Honour, J; Anker, S; Coats, A

2001-01-01

OBJECTIVE—To evaluate urinary glucocorticoid excretion profiles in a cohort of recently diagnosed young hypertensive patients.
METHODS—After excluding patients with secondary causes, 60 individuals with premature hypertension were recruited (diagnosed by ambulatory blood pressure monitoring before the age of 36 years). In addition, 30 older hypertensive controls (age of onset > 36 years, "middle aged hypertensive controls"), and 30 normal controls (age matched to the young hypertensive group) were studied. All provided 24 hour urine collections for mass spectrometry for total cortisol metabolites and total androgen metabolites by gas chromatography.
RESULTS—Among male patients, those with premature hypertension had higher total urinary excretion of cortisol metabolites (mean (SD), 13 332 (6472) µg/day) than age matched normal controls (7270 (1788) µg/day; p = 0.00001) or middle aged hypertensive controls (8315 (3565) µg/day; p = 0.002). A similar increase was seen among the female patients, although the absolute concentrations were lower. There was no significant difference between middle aged hypertensive patients and normal controls. Urinary total androgen excretion profiles in female patients also showed an unusual increase in the premature hypertension group (2958 (1672) µg/day) compared with the other groups (middle aged hypertensive controls, 1373 (748) µg/day, p = 0.0003; normal controls, 1687 (636) µg/day, p = 0.002). In all subjects, serum sodium and creatinine concentrations were within the normal range; serum potassium concentrations were found to be low before the start of treatment.
CONCLUSIONS—Individuals presenting with premature hypertension have an abnormally high excretion of glucocorticoid metabolites in the urine. While the mechanism remains uncertain, these findings are compatible with partial resistance of the glucocorticoid receptors, with a compensatory increase in cortisol and androgen metabolites. The mineralocorticoid effects of the latter (sodium and water retention) may contribute to an abnormally high blood pressure and may have implications for targeted selection of first line treatment in young hypertensive patients.


Keywords: premature hypertension; glucocorticoid resistance; cortisol metabolites; glucocorticoid receptor resistance PMID:11454825

Decreased fractional urinary calcium excretion and serum 1,25-dihydroxyvitamin D and IGF-I levels in preeclampsia.

PubMed

Halhali, Ali; Díaz, Lorenza; Avila, Euclides; Ariza, Ana Carolina; Garabédian, Michèle; Larrea, Fernando

2007-03-01

During preeclampsia several alterations of calcium metabolism have been described, the most common of them is hypocalciuria, which pathophysiology is still unclear. In order to assess the contribution of calciotropic hormones to urinary calcium excretion, a cross-sectional study was done including 26 preeclamptic Mexican women (PE group) and 26 normotensive control pregnant women (NT group). Total and fractional urinary calcium excretion were significantly lower (P<0.0001) in the PE group than in the NT group (82+/-7 versus 171+/-7 mg/24h and 0.62+/-0.38 versus 1.38+/-0.71%, respectively), without significant differences in creatinine clearance, urinary sodium excretion and phosphate tubular reabsorption. In addition, serum 1,25-(OH)(2)D and IGF-I levels were significantly (P<0.05) lower in the PE than in NT group (43+/-9 versus 50+/-9 pg/mL and 195+/-67 versus 293+/-105 ng/mL, respectively), without significant differences in serum PTH levels. In the NT group, association analysis showed that total and fractional urinary calcium excretions positively correlated with serum levels of 1,25-(OH)(2)D (P<0.01) and IGF-I (P<0.001). In the PE group, total urinary calcium excretion positively correlated only with serum 1,25-(OH)(2)D (P<0.05). In conclusion, the results obtained in this study confirm that PE is associated with hypocalciuria and suggest that 1,25-(OH)(2)D and/or IGF-I may be involved in the regulation of urinary calcium excretion.

Increased Klk9 Urinary Excretion Is Associated to Hypertension-Induced Cardiovascular Damage and Renal Alterations.

PubMed

Blázquez-Medela, Ana M; García-Sánchez, Omar; Quirós, Yaremi; Blanco-Gozalo, Victor; Prieto-García, Laura; Sancho-Martínez, Sandra M; Romero, Miguel; Duarte, Juan M; López-Hernández, Francisco J; López-Novoa, José M; Martínez-Salgado, Carlos

2015-10-01

Early detection of hypertensive end-organ damage and secondary diseases are key determinants of cardiovascular prognosis in patients suffering from arterial hypertension. Presently, there are no biomarkers for the detection of hypertensive target organ damage, most outstandingly including blood vessels, the heart, and the kidneys.We aimed to validate the usefulness of the urinary excretion of the serine protease kallikrein-related peptidase 9 (KLK9) as a biomarker of hypertension-induced target organ damage.Urinary, plasma, and renal tissue levels of KLK9 were measured by the Western blot in different rat models of hypertension, including angiotensin-II infusion, DOCA-salt, L-NAME administration, and spontaneous hypertension. Urinary levels were associated to cardiovascular and renal injury, assessed by histopathology. The origin of urinary KLK9 was investigated through in situ renal perfusion experiments.The urinary excretion of KLK9 is increased in different experimental models of hypertension in rats. The ACE inhibitor trandolapril significantly reduced arterial pressure and the urinary level of KLK9. Hypertension did not increase kidney, heart, liver, lung, or plasma KLK9 levels. Hypertension-induced increased urinary excretion of KLK9 results from specific alterations in its tubular reabsorption, even in the absence of overt nephropathy. KLK9 urinary excretion strongly correlates with cardiac hypertrophy and aortic wall thickening.KLK9 appears in the urine in the presence of hypertension as a result of subtle renal handling alterations. Urinary KLK9 might be potentially used as an indicator of hypertensive cardiac and vascular damage.

A Dietary Intervention in Urban African Americans

PubMed Central

Miller, Edgar R.; Cooper, Lisa A.; Carson, Kathryn A.; Wang, Nae-Yuh; Appel, Lawrence J.; Gayles, Debra; Charleston, Jeanne; White, Karen; You, Na; Weng, Yingjie; Martin-Daniels, L. Michelle; Bates-Hopkins, Barbara; Robb, Inez; Franz, Whitney K.; Brown, Emily L.; Halbert, Jennifer P.; Albert, Michael C.; Dalcin, Arlene T.; Yeh, Hsin-Chieh

2015-01-01

Introduction Unhealthy diets, often low in potassium, likely contribute to racial disparities in blood pressure. We tested the effectiveness of providing weekly dietary advice, assistance with selection of higher potassium grocery items, and a $30 per week food allowance on blood pressure and other outcomes in African American adults with hypertension. Design We conducted an 8-week RCT with two parallel arms between May 2012 and November 2013. Setting/participants We randomized 123 African Americans with controlled hypertension from an urban primary care clinic in Baltimore, Maryland and implemented the trial in partnership with a community supermarket and the Baltimore City Health Department. Mean (SD) age was 58.6 (9.5) years, 71% were female, blood pressure was 131.3 (14.7)/77.2 (10.5) mmHg, BMI was 34.5 (8.2) kg/m2, and 28% had diabetes. Intervention Participants randomized to the active intervention group (Dietary Approaches to Stop Hypertension [DASH]-Plus) received coach-directed dietary advice and assistance with weekly online ordering and purchasing of high-potassium foods ($30/week) delivered by a community supermarket to a neighborhood library. Participants in the control group received a printed DASH diet brochure along with debit account of equivalent value to that of the DASH-Plus group. Main outcome measures The primary outcome was blood pressure change. Analyses were conducted in January to October 2014. Results Compared with the control group, the DASH-Plus group increased self-reported consumption of fruits and vegetables (mean=1.4, 95% CI=0.7, 2.1 servings/day), estimated intake of potassium (mean=0.4, 95% CI=0.1, 0.7 grams/day), and urine potassium excretion (mean=19%, 95% CI=1%, 38%). There was no significant effect on blood pressure. Conclusions A program providing dietary advice, assistance with grocery ordering, and $30/week of high-potassium foods in African American patients with controlled hypertension in a community-based clinic did not reduce BP. However, the intervention increased consumption of fruits, vegetables, and urinary excretion of potassium. PMID:26321012

A Dietary Intervention in Urban African Americans: Results of the "Five Plus Nuts and Beans" Randomized Trial.

PubMed

Miller, Edgar R; Cooper, Lisa A; Carson, Kathryn A; Wang, Nae-Yuh; Appel, Lawrence J; Gayles, Debra; Charleston, Jeanne; White, Karen; You, Na; Weng, Yingjie; Martin-Daniels, Michelle; Bates-Hopkins, Barbara; Robb, Inez; Franz, Whitney K; Brown, Emily L; Halbert, Jennifer P; Albert, Michael C; Dalcin, Arlene T; Yeh, Hsin-Chieh

2016-01-01

Unhealthy diets, often low in potassium, likely contribute to racial disparities in blood pressure. We tested the effectiveness of providing weekly dietary advice, assistance with selection of higher potassium grocery items, and a $30 per week food allowance on blood pressure and other outcomes in African American adults with hypertension. We conducted an 8-week RCT with two parallel arms between May 2012 and November 2013. We randomized 123 African Americans with controlled hypertension from an urban primary care clinic in Baltimore, Maryland, and implemented the trial in partnership with a community supermarket and the Baltimore City Health Department. Mean (SD) age was 58.6 (9.5) years; 71% were female; blood pressure was 131.3 (14.7)/77.2 (10.5) mmHg; BMI was 34.5 (8.2); and 28% had diabetes. Participants randomized to the active intervention group (Dietary Approaches to Stop Hypertension [DASH]-Plus) received coach-directed dietary advice and assistance with weekly online ordering and purchasing of high-potassium foods ($30/week) delivered by a community supermarket to a neighborhood library. Participants in the control group received a printed DASH diet brochure along with a debit account of equivalent value to that of the DASH-Plus group. The primary outcome was blood pressure change. Analyses were conducted in January to October 2014. Compared with the control group, the DASH-Plus group increased self-reported consumption of fruits and vegetables (mean=1.4, 95% CI=0.7, 2.1 servings/day); estimated intake of potassium (mean=0.4, 95% CI=0.1, 0.7 grams/day); and urine potassium excretion (mean=19%, 95% CI=1%, 38%). There was no significant effect on blood pressure. A program providing dietary advice, assistance with grocery ordering, and $30/week of high-potassium foods in African American patients with controlled hypertension in a community-based clinic did not reduce BP. However, the intervention increased consumption of fruits, vegetables, and urinary excretion of potassium. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Hormonal disturbances in visceral leishmaniasis (kala-azar).

PubMed

Verde, Frederico Araujo Lima; Verde, Francisco Agenor Araujo Lima; Neto, Augusto Saboia; Almeida, Paulo César; Verde, Emir Mendonça Lima

2011-05-01

This study presents a cross-sectional analysis of the hormonal alterations of patients with visceral leishmaniasis. The diagnosis was established by the bone marrow aspiration and polymerase chain reaction test. Primary adrenal insufficiency was observed in 45.8% of patients; low aldosterone/renin plasma ratio in 69.4%; low daily urinary aldosterone excretion in 61.1%; and low transtubular potassium gradient in 68.0%. All patients had normal plasma antidiuretic hormone (ADH) concentrations, hyponatremia, and high urinary osmolality. Plasma parathyroid hormone was low in 63%; hypomagnesemia was present in 46.4%, and increased Mg(++)(EF) in 100%. Primary thyroid insufficiency was observed in 24.6%, and secondary thyroid insufficiency in 14.1%. Normal follicle-stimulating hormone plasma levels were present in 81.4%; high luteinizing hormone and low testosterone plasma levels in 58.2% of men. There are evidences of hypothalamus-pituitary-adrenal axis abnormalities, inappropriate aldosterone and ADH secretions, and presence of hypoparathyroidism, magnesium depletion, thyroid and testicular insufficiencies.

Sodium and water metabolism under the influence of prolactin, aldosterone, and antidiuretic hormone.

PubMed Central

Burstyn, P G

1978-01-01

1. Rabbits were placed in metabolism cages in order to measure their intakes of food, water, and sodium chloride (as 1% saline solution), and to measure urinary and faecal excretion of sodium, potassium, and water. 2. Antidiuretic hormone (0.2 i.u./day) caused a reduction in urine volume and no change in sodium excretion. There was full compensatory reduction in water intake so that no accumulation of water occurred. 3. Aldosterone (4 mg/da) caused a reduction in renal sodium excretion for 1--2 days. The saline intake was reduced, though this was insufficient to prevent some sodium accumulation. 4. Renal mineralocorticoid 'escape' resulted in a large increase in sodium excretion at the end of the aldosterone treatment period. This was fully compensated through increased saline intake, and balance was maintained. 5. Prolactin (200 i.u./day) caused a reduction in urine volume and in renal sodium excretion and since there were no compensatory changes in water and sodium intake, this led to substantial accumulation of both water and sodium. 6. The effects of smaller doses of both aldosterone and prolactin were investigated and found to be similar but smaller. 7. It is suggested that whereas prolactin may have little or no role to play in the sodium homoeostasis of the normal animal, the hormone may well be responsible for the substantial increase in body fluids in pregnancy. PMID:633132

Effect of high dietary sodium on bone turnover markers and urinary calcium excretion in Korean postmenopausal women with low bone mass.

PubMed

Park, S M; Joung, J Y; Cho, Y Y; Sohn, S Y; Hur, K Y; Kim, J H; Kim, S W; Chung, J H; Lee, M K; Min, Y-K

2015-03-01

High salt intake is a well-recognized risk factor of osteoporosis for its modulating effect on calcium metabolism. To understand the effect of dietary sodium on bone turnover, we evaluated the association between urinary sodium excretion and bone turnover markers in Korean postmenopausal women with low bone mass. A retrospective review of medical records at a single institution identified 537 postmenopausal women who were first diagnosed with osteopenia or osteoporosis between 2008 and 2013. Subjects were stratified by low (<2 g/day, n=77), moderate (2-4.4 g/day, n=354) and high (⩾4.4 g/day, n=106) sodium excretion. A 24-h urine was collected to estimate sodium, calcium and creatinine. Bone turnover markers and calciotropic hormones were measured in serum. Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry. Sodium intake was positively associated with urinary sodium excretion (P=0.006, r=0.29). Bone turnover markers were significantly higher in the moderate-to-high urinary sodium excretion group (⩾2 g/day) than in the low urinary sodium excretion group (<2 g/day); CTX-I (C-telopeptides of type I collagen) was 21.3% higher (P=0.001) and osteocalcin (OC) was 15.7% higher (P=0.004). Calciotropic hormones and BMD were not significantly different across the sodium excretion groups. High urinary sodium excretion (⩾2 g/day) increased bone turnover markers in Korean postmenopausal women, suggesting that excessive sodium intake might accelerate bone turnover.

Urinary 24-h creatinine excretion in adults and its use as a simple tool for the estimation of daily urinary analyte excretion from analyte/creatinine ratios in populations.

PubMed

Johner, S A; Boeing, H; Thamm, M; Remer, T

2015-12-01

The assessment of urinary excretion of specific nutrients (e.g. iodine, sodium) is frequently used to monitor a population's nutrient status. However, when only spot urines are available, always a risk of hydration-status-dependent dilution effects and related misinterpretations exists. The aim of the present study was to establish mean values of 24-h creatinine excretion widely applicable for an appropriate estimation of 24-h excretion rates of analytes from spot urines in adults. Twenty-four-hour creatinine excretion from the formerly representative cross-sectional German VERA Study (n=1463, 20-79 years old) was analysed. Linear regression analysis was performed to identify the most important influencing factors of creatinine excretion. In a subsample of the German DONALD Study (n=176, 20-29 years old), the applicability of the 24-h creatinine excretion values of VERA for the estimation of 24-h sodium and iodine excretion from urinary concentration measurements was tested. In the VERA Study, mean 24-h creatinine excretion was 15.4 mmol per day in men and 11.1 mmol per day in women, significantly dependent on sex, age, body weight and body mass index. Based on the established 24-h creatinine excretion values, mean 24-h iodine and sodium excretions could be estimated from respective analyte/creatinine concentrations, with average deviations <10% compared with the actual 24-h means. The present mean values of 24-h creatinine excretion are suggested as a useful tool to derive realistic hydration-status-independent average 24-h excretion rates from urinary analyte/creatinine ratios. We propose to apply these creatinine reference means routinely in biomarker-based studies aiming at characterizing the nutrient or metabolite status of adult populations by simply measuring metabolite/creatinine ratios in spot urines.

Renal-Stone Risk Assessment During Space Shuttle Flights

NASA Technical Reports Server (NTRS)

Whitson, Peggy A.; Pietrzyk, Robert A.; Pak, Charles Y. C.

1996-01-01

The metabolic and environmental factors influencing renal stone formation before, during, and after Space Shuttle flights were assessed. We established the contributing roles of dietary factors in relationship to the urinary risk factors associated with renal stone formation. 24-hr urine samples were collected prior to, during space flight, and following landing. Urinary factors associated with renal stone formation were analyzed and the relative urinary supersaturation ratios of calcium oxalate, calcium phosphate (brushite), sodium urate, struvite and uric acid were calculated. Food and fluid consumption was recorded for a 48-hr period ending with the urine collection. Urinary composition changed during flight to favor the crystallization of stone-forming salts. Factors that contributed to increased potential for stone formation during space flight were significant reductions in urinary pH and increases in urinary calcium. Urinary output and citrate, a potent inhibitor of calcium-containing stones, were slightly reduced during space flight. Dietary intakes were significantly reduced for a number of variables, including fluid, energy, protein, potassium, phosphorus and magnesium. This is the first in-flight characterization of the renal stone forming potential in astronauts. With the examination of urinary components and nutritional factors, it was possible to determine the factors that contributed to increased risk or protected from risk. In spite of the protective components, the negative contributions to renal stone risk predominated and resulted in a urinary environment that favored the supersaturation of stone-forming salts. The importance of the hypercalciuria was noted since renal excretion was high relative to the intake.

Urinary Excretion of N-Nitroso Compounds in Rats Fed Sodium Nitrite and/or Hot Dogs

PubMed Central

2015-01-01

Nitrite-treated meat is a reported risk factor for colon cancer. Mice that ingested sodium nitrite (NaNO2) or hot dogs (a nitrite-treated product) showed increased fecal excretion of apparent N-nitroso compounds (ANC). Here, we investigated for the first time whether rats excrete increased amounts of ANC in their urine after they are fed NaNO2 and/or hot dogs. Rats were treated for 7 days with NaNO2 in drinking water or were fed hot dogs. Their 24 h urine samples were analyzed for ANC by thermal energy analysis on days 1–4 after nitrite or hot dog treatment was stopped. For two rats fed 480 mg NaNO2/L drinking water, mean urinary ANC excretion on days 1–4 was 30, 5.2, 2.5, and 0.8 nmol/day, respectively. For two to eight rats/dose given varied NaNO2 doses, mean urinary ANC output on day 1 increased from 0.9 (for no nitrite) to 37 (for 1000 mg NaNO2/L drinking water) nmol ANC/day. Urine samples of four rats fed 40–60% hot dogs contained 12–13 nmol ANC on day 1. Linear regression analysis showed highly significant correlations between urinary ANC excretion on day 1 after stopping treatment and varied (a) NaNO2 level in drinking water for rats fed semipurified or commercials diet and (b) hot dog levels in the diet. Some correlations remained significant up to 4 days after nitrite treatment was stopped. Urinary output of ANC precursors (compounds that yield ANC after mild nitrosation) for rats fed semipurified or commercial diet was 11–17 or 23–48 μmol/day, respectively. Nitrosothiols and iron nitrosyls were not detected in urinary ANC and ANCP. Excretion of urinary ANC was about 60% of fecal ANC excretion for 1 to 2 days after NaNO2 was fed. Administered NaNO2 was not excreted unchanged in rat urine. We conclude that urinary ANC excretion in humans could usefully be surveyed to indicate exposure to N-nitroso compounds. PMID:25183213

Urinary Angiotensinogen Excretion Level Is Associated With Elevated Blood Pressure in the Normotensive General Population.

PubMed

Sato, Emiko; Wang, An Yi; Satoh, Michihiro; Nishikiori, Yoko; Oba-Yabana, Ikuko; Yoshida, Mai; Sato, Hiroshi; Ito, Sadayoshi; Hida, Wataru; Mori, Takefumi

2018-05-07

Inflammation, intrarenal renin-angiotensin system (RAS) activation, oxidative stress, and carbonyl stress have been postulated to play a fundamental role in controlling blood pressure. However, little is known about the association among renal RAS activation, carbonyl stress, and blood pressure elevation. We evaluated the relationship between blood pressure elevation and either renal RAS activity or carbonyl stress in the general population (N = 355) in Japan. To minimize the effect of antihypertensive drug therapy, we divided participants into 3 groups (normotensive, hypertensive-with-non-medication, and hypertensive-with-medication). Intrarenal RAS activity and carbonyl stress were indicated by the urinary angiotensinogen (AGT) and carbonyl compound excretion levels, respectively. The urinary AGT and carbonyl compound excretion levels were significantly associated with blood pressure. Using a stepwise multiple regression analysis, we found that the urinary AGT excretion levels were strongly associated with blood pressure elevation, compared with inflammation, oxidative stress, and carbonyl stress markers, in all groups. Urinary carbonyl compound excretion was significantly associated with blood pressure in only the hypertensive-without-medication group. Furthermore, blood pressure was significantly increased in these participants, and both the urinary AGT and carbonyl compound levels were high. The urinary AGT excretion levels were strongly associated with elevated blood pressure in normotensive people, and inappropriate renal RAS activity and carbonyl stress independently contributed to the development of hypertension. These findings suggest that RAS activation, particularly renal RAS activation exert a fundamental role in the pathogenesis of hypertension in the general population.

Role of vasopressin in regulation of renal kinin excretion in Long-Evans and diabetes insipidus rats.

PubMed Central

Kauker, M L; Crofton, J T; Share, L; Nasjletti, A

1984-01-01

To study the relationship between vasopressin and the renal kallikrein-kinin system we measured the rate of excretion of kinins into the urine of anesthetized rats during conditions of increased and decreased vasopressin level. The excretion of immunoreactive kinins in Brattleboro rats with hereditary diabetes insipidus (DI) (24 +/- 3 pg min-1 kg-1) was lower than in the control Long Evans (LE) rats (182 +/- 22 pg min-1 kg-1; P less than 0.05). The DI rats also exhibited negligible urinary excretion of immunoreactive vasopressin, reduced urine osmolality, and increased urine flow and kininogenase excretion. In LE rats, volume expansion by infusion of 0.45% NaCl-2.5% dextrose to lower vasopressin secretion reduced (P less than 0.05) kinin excretion, vasopressin excretion, and urine osmolality to 41, 26, and 15% of their respective control values, while increasing (P less than 0.05) urine flow and kininogenase excretion. On the other hand, the infusion of 5% NaCl, which promotes vasopressin secretion, increased (P less than 0.05) the urinary excretion of kinins and vasopressin to 165 and 396% of control, while increasing (P less than 0.05) urine flow and kininogenase excretion. Infusion of vasopressin (1.2 mU/h, intravenous) enhanced (P less than 0.05) kinin excretion by two to threefold in DI rats and in LE rats during volume expansion with 0.45% NaCl-2.5% dextrose, while decreasing urine flow and increasing urine osmolality. This study demonstrates that the urinary excretion of immunoreactive kinins varies in relation to the urinary level of vasopressin, irrespective of urine volume and osmolality and of the urinary excretions of sodium and kininogenase. The study suggests a role for vasopressin in promoting the activity of the renal kallikrein-kinin system in the rat. PMID:6561201

Estimated Net Endogenous Acid Production and Serum Bicarbonate in African Americans with Chronic Kidney Disease

PubMed Central

Appel, Lawrence J.; Astor, Brad C.; Miller, Edgar R.; Beddhu, Srinivasan; Woodward, Mark; Parekh, Rulan S.; Anderson, Cheryl A.M.

2011-01-01

Summary Background and objectives Metabolic acidosis may contribute to morbidity and disease progression in patients with chronic kidney disease (CKD). The ratio of dietary protein, the major source of nonvolatile acid, to dietary potassium, which is naturally bound to alkali precursors, can be used to estimate net endogenous acid production (NEAP). We tested the association between estimated NEAP and serum bicarbonate in patients with CKD. Design, setting, participants, & measurements NEAP was estimated among 462 African American adults with hypertensive CKD using published equations: NEAP (mEq/d) = −10.2 + 54.5 (protein [g/d]/potassium [mEq/d]). Dietary protein and potassium intake were estimated from 24-hour urinary excretion of urea nitrogen and potassium, respectively. All of the eligible measurements during follow-up were modeled using generalized linear regression clustered by participant and adjusted for demographics, 24-hour urinary sodium, kidney function, and selected medications. Results Higher NEAP was associated with lower serum bicarbonate in a graded fashion (P trend < 0.001). Serum bicarbonate was 1.27 mEq/L lower among those in the highest compared with the lowest quartile of NEAP (P < 0.001). There was a greater difference in serum bicarbonate between the highest and lowest quartiles of NEAP among patients with stage 4/5 CKD (−2.43 mEq/L, P < 0.001) compared with those with stage 2/3 disease (−0.77 mEq/L, P = 0.01; P-interaction = 0.02). Conclusions Reducing NEAP, through reduction of dietary protein and increased intake of fruits and vegetables, may prevent metabolic acidosis in patients with CKD. PMID:21700817

Renal Function, Bisphenol A, and Alkylphenols: Results from the National Health and Nutrition Examination Survey (NHANES 2003–2006)

PubMed Central

You, Li; Zhu, Xiangzhu; Shrubsole, Martha J.; Fan, Hong; Chen, Jing; Dong, Jie; Hao, Chuan-Ming; Dai, Qi

2011-01-01

Background Urinary excretion of bisphenol A (BPA) and alkylphenols (APs) was used as a biomarker in most previous studies, but no study has investigated whether urinary excretion of these environmental phenols differed by renal function. Objective We estimated the association between renal function and urinary excretion of BPA and APs. Methods Analyses were conducted using data from the National Health and Nutrition Examination Survey (NHANES) 2003–2006. Renal function was measured as estimated glomerular filtration rate (eGFR) calculated by the Modification of Diet in Renal Disease (MDRD) Study equation and by the newly developed Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Regression models were used to calculate geometric means of urinary BPA and APs excretion by eGFR category (≥ 90, 60–90, < 60 mL/min/m2) after adjusting for potential confounding factors. Results When we used the MDRD Study equation, participants without known renal disease (n = 2,573), 58.2% (n = 1,499) had mildly decreased renal function or undiagnosed chronic kidney disease. The adjusted geometric means for urinary BPA excretion decreased with decreasing levels of eGFR (p for trend = 0.04). The associations appeared primarily in females (p for trend = 0.03). Urinary triclosan excretion decreased with decreasing levels of eGFR (p for trend < 0.01) for both males and females, and the association primarily appeared in participants < 65 years of age. The association between BPA and eGFR was nonsignificant when we used the CKD-EPI equation. Conclusions Urinary excretion of triclosan, and possibly BPA, decreased with decreasing renal function. The associations might differ by age or sex. Further studies are necessary to replicate our results and understand the mechanism. PMID:21147601

Iodine Excretion in 24-hour Urine Collection and Its Dietary Determinants in Healthy Japanese Adults

PubMed Central

Katagiri, Ryoko; Asakura, Keiko; Uechi, Ken; Masayasu, Shizuko; Sasaki, Satoshi

2016-01-01

Background Since seaweed is a common component of the Japanese diet, iodine intake in Japanese is expected to be high. However, urinary iodine excretion, measured using 24-hour urine samples, and its dietary determinants are not known. Methods Apparently healthy adults aged 20 to 69 years living in 20 areas throughout Japan were recruited in February and March, 2013. Urinary iodine excretion was evaluated using 24-hour urine collected from 713 subjects (362 men and 351 women), and the difference among age groups was assessed. The association between dietary intake of food groups and urinary iodine excretion was assessed among 358 subjects who completed a semi-weighed 4-day diet record (DR) and urine collection. The correlations between iodine intake and iodine excretion were also evaluated, and correlation coefficients were calculated for iodine intake in the DR of the overlapping day or the DR 1 day before and after urine collection. Results Median iodine excretion in 24-hour urine was 365 µg, and excretion was significantly higher in older subjects. Iodine intake estimated by the DRs was significantly correlated with urinary iodine excretion when DRs and urine collection were obtained on the same day (r = 0.37). After adjustment for confounding factors, iodine excretion was significantly associated with intakes of kelp and soup stock from kelp and fish. Conclusions Although multiple measurements for urinary iodine are required to confirm our results, this study showed the current iodine status of healthy Japanese adults. The results suggest that kelp and fish are the main contributors to Japanese iodine status measured by 24-hour urine. PMID:27374137

Increased urinary excretion of thioether in new rubber workers

PubMed Central

Kilpikari, I; Savolainen, H

1982-01-01

ABSTRACT Urinary excretion of thioether before starting work and in the early work period in a rubber factory was measured in urine samples collected after one, two to four, and five or more months of starting work. The study population consisted of 84 new workers. The urinary excretion of thioether decreased after one month's exposure and increased thereafter up to five months. Measurement of urinary thioethers in groups of new workers is therefore informative of exposure to alkylating agents only after several months from starting work. This effect may be mediated by the induction of the pertinent metabolic pathway. PMID:7138800

The Kallikrein-Kinin System in Bartter's Syndrome and Its Response to Prostaglandin Synthetase Inhibition

PubMed Central

Vinci, Joseph M.; Gill, John R.; Bowden, Robert E.; Pisano, John J.; Izzo, Joseph L.; Radfar, Nazam; Taylor, Addison A.; Zusman, Randall M.; Bartter, Frederic C.; Keiser, Harry R.

1978-01-01

The kallikrein-kinin system was characterized in seven patients with Bartter's syndrome on constant metabolic regimens before, during, and after treatment with prostaglandin synthetase inhibitors. Patients with Bartter's syndrome had high values for plasma bradykinin, plasma renin activity (PRA), urinary kallikrein, urinary immunoreactive prostaglandin E excretion, and urinary aldosterone; urinary kinins were subnormal and plasma prekallikrein was normal. Treatment with indomethacin or ibuprofen which decreased urinary immunoreactive prostaglandin E excretion by 67%, decreased mean PRA (patients recumbent) from 17.3±5.3 (S.E.M.) ng/ml per h to 3.3±1.1 ng/ml per h, mean plasma bradykinin (patients recumbent) from 15.4±4.4 ng/ml to 3.9±0.9 ng/ml, mean urinary kallikrein excretion from 24.8±3.2 tosyl-arginine-methyl ester units (TU)/day to 12.4±2.0 TU/day, but increased mean urinary kinin excretion from 3.8±1.3 μg/day to 8.5±2.5 μg/day. Plasma prekallikrein remained unchanged at 1.4 TU/ml. Thus, with prostaglandin synthetase inhibition, values for urinary kallikrein and kinin and plasma bradykinin returned to normal pari passu with changes in PRA, in aldosterone, and in prostaglandin E. The results suggest that, in Bartter's syndrome, prostaglandins mediate the low urinary kinins and the high plasma bradykinin, and that urinary kallikrein, which is aldosterone dependent, does not control kinin excretion. The high plasma bradykinin may be a cause of the pressor hyporesponsiveness to angiotensin II which characterizes the syndrome. PMID:96139

Increased Klk9 Urinary Excretion Is Associated to Hypertension-Induced Cardiovascular Damage and Renal Alterations

PubMed Central

Blázquez-Medela, Ana M.; García-Sánchez, Omar; Quirós, Yaremi; Blanco-Gozalo, Victor; Prieto-García, Laura; Sancho-Martínez, Sandra M.; Romero, Miguel; Duarte, Juan M.; López-Hernández, Francisco J.; López-Novoa, José M.; Martínez-Salgado, Carlos

2015-01-01

Abstract Early detection of hypertensive end-organ damage and secondary diseases are key determinants of cardiovascular prognosis in patients suffering from arterial hypertension. Presently, there are no biomarkers for the detection of hypertensive target organ damage, most outstandingly including blood vessels, the heart, and the kidneys. We aimed to validate the usefulness of the urinary excretion of the serine protease kallikrein-related peptidase 9 (KLK9) as a biomarker of hypertension-induced target organ damage. Urinary, plasma, and renal tissue levels of KLK9 were measured by the Western blot in different rat models of hypertension, including angiotensin-II infusion, DOCA-salt, L-NAME administration, and spontaneous hypertension. Urinary levels were associated to cardiovascular and renal injury, assessed by histopathology. The origin of urinary KLK9 was investigated through in situ renal perfusion experiments. The urinary excretion of KLK9 is increased in different experimental models of hypertension in rats. The ACE inhibitor trandolapril significantly reduced arterial pressure and the urinary level of KLK9. Hypertension did not increase kidney, heart, liver, lung, or plasma KLK9 levels. Hypertension-induced increased urinary excretion of KLK9 results from specific alterations in its tubular reabsorption, even in the absence of overt nephropathy. KLK9 urinary excretion strongly correlates with cardiac hypertrophy and aortic wall thickening. KLK9 appears in the urine in the presence of hypertension as a result of subtle renal handling alterations. Urinary KLK9 might be potentially used as an indicator of hypertensive cardiac and vascular damage. PMID:26469898

Technical Basis Document: A Statistical Basis for Interpreting Urinary Excretion of Plutonium Based on Accelerator Mass Spectrometry (AMS) for Selected Atoll Populations in the Marshall Islands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bogen, K; Hamilton, T F; Brown, T A

2007-05-01

We have developed refined statistical and modeling techniques to assess low-level uptake and urinary excretion of plutonium from different population group in the northern Marshall Islands. Urinary excretion rates of plutonium from the resident population on Enewetak Atoll and from resettlement workers living on Rongelap Atoll range from <1 to 8 {micro}Bq per day and are well below action levels established under the latest Department regulation 10 CFR 835 in the United States for in vitro bioassay monitoring of {sup 239}Pu. However, our statistical analyses show that urinary excretion of plutonium-239 ({sup 239}Pu) from both cohort groups is significantly positivelymore » associated with volunteer age, especially for the resident population living on Enewetak Atoll. Urinary excretion of {sup 239}Pu from the Enewetak cohort was also found to be positively associated with estimates of cumulative exposure to worldwide fallout. Consequently, the age-related trends in urinary excretion of plutonium from Marshallese populations can be described by either a long-term component from residual systemic burdens acquired from previous exposures to worldwide fallout or a prompt (and eventual long-term) component acquired from low-level systemic intakes of plutonium associated with resettlement of the northern Marshall Islands, or some combination of both.« less

The relationship between sodium excretion and blood pressure, urine albumin, central retinal arteriolar equivalent.

PubMed

Huang, Feng; Yu, Peng; Yuan, Yin; Li, Qiaowei; Lin, Fan; Gao, Zhonghai; Chen, Falin; Zhu, Pengli

2016-10-11

Many studies showed an association between dietary salt intake, blood pressure and increased CVD risk. The potential reason may be related to vascular structural and functional changes, through alterations in endothelial function. The central retinal arteriolar equivalent and urinary albumin reflected vascular endothelial dysfunction in different part of the body. The urinary sodium-creatinine ratio of causal urine specimens could represent the 24-h urinary sodium intake to estimate sodium intake. The 24-h sodium excretion was estimated by urinary sodium-creatinine ratio. Urinary albumin-creatinine ratio (UACR), reflecting renal arterial damage, was also determined. The central retinal arteriolar equivalent (CRAE) was detected by fundus photography and was further analyzed by semi-quantitative software. Participants included 951 hypertensive patients with the average sodium excretion of 11.62 ± 3.01 g. The sodium excretion was significantly higher (P < 0.01) in the hypertensive as compared to that of the non-hypertensive participants. Prevalence of hypertension was increased with increasing sodium excretion. The sodium excretion was positively correlated with systolic blood pressure (SBP) and diastolic blood pressure (DBP), respectively (r = 0.20 and 0.14; P < 0.01). Furthermore, UACR and CRAE were significantly (P < 0.01) different within the sodium excretion quartiles (Q1-Q4). After adjusting the confounding variables, such as age and sex, the binary logistic regression analysis showed that sodium excretion was an independent factor of UACR and CRAE (P < 0.01). Our results suggest that sodium excretion in the hypertensive participants were higher. The high sodium excretion was related with the renal arterial damage as well as retinal arteriolar changes.

Contribution of dietary oxalate to urinary oxalate excretion

NASA Technical Reports Server (NTRS)

Holmes, R. P.; Goodman, H. O.; Assimos, D. G.

2001-01-01

BACKGROUND: The amount of oxalate excreted in urine has a significant impact on calcium oxalate supersaturation and stone formation. Dietary oxalate is believed to make only a minor (10 to 20%) contribution to the amount of oxalate excreted in urine, but the validity of the experimental observations that support this conclusion can be questioned. An understanding of the actual contribution of dietary oxalate to urinary oxalate excretion is important, as it is potentially modifiable. METHODS: We varied the amount of dietary oxalate consumed by a group of adult individuals using formula diets and controlled, solid-food diets with a known oxalate content, determined by a recently developed analytical procedure. Controlled solid-food diets were consumed containing 10, 50, and 250 mg of oxalate/2500 kcal, as well as formula diets containing 0 and 180 mg oxalate/2500 kcal. Changes in the content of oxalate and other ions were assessed in 24-hour urine collections. RESULTS: Urinary oxalate excretion increased as dietary oxalate intake increased. With oxalate-containing diets, the mean contribution of dietary oxalate to urinary oxalate excretion ranged from 24.4 +/- 15.5% on the 10 mg/2500 kcal/day diet to 41.5 +/- 9.1% on the 250 mg/2500 kcal/day diet, much higher than previously estimated. When the calcium content of a diet containing 250 mg of oxalate was reduced from 1002 mg to 391 mg, urinary oxalate excretion increased by a mean of 28.2 +/- 4.8%, and the mean dietary contribution increased to 52.6 +/- 8.6%. CONCLUSIONS: These results suggest that dietary oxalate makes a much greater contribution to urinary oxalate excretion than previously recognized, that dietary calcium influences the bioavailability of ingested oxalate, and that the absorption of dietary oxalate may be an important factor in calcium oxalate stone formation.

Roles of renal ammonia metabolism other than in acid-base homeostasis

PubMed Central

Weiner, I. David

2016-01-01

The importance of renal ammonia metabolism in acid-base homeostasis is well known. However, the effects of renal ammonia metabolism other than in acid-base homeostasis are not as widely recognized. First, ammonia differs from almost all other solutes in the urine in that it does not result from arterial delivery. Instead, ammonia is produced by the kidney and only a portion of the ammonia produced is excreted in the urine. The remainder is returned to the systemic circulation through the renal veins. In normal individuals, systemic ammonia addition is metabolized efficiently by the liver, but in patients with either acute or chronic liver disease, conditions that increase renal ammonia addition to the systemic circulation can cause precipitation and/or worsening of hyperammonemia. Second, ammonia appears to serve as an intra-renal paracrine signaling molecule. Hypokalemia increases proximal tubule ammonia production and secretion and it increases reabsorption in the thick ascending limb of the loop of Henle, thereby increasing delivery to the renal interstitium and the collecting duct. In the collecting duct, ammonia decreases potassium secretion and stimulates potassium reabsorption, thereby decreasing urinary potassium excretion and enabling feedback correction of the initiating hypokalemia. Finally, hypokalemia’s stimulation of renal ammonia metabolism and hypokalemia contributes to development of metabolic alkalosis, which can stimulate NaCl reabsorption and thereby contribute to the intravascular volume expansion, increased blood pressure and diuretic resistance that can develop with hypokalemia. In this review, we discuss the evidence supporting these novel non-acid-base roles of renal ammonia metabolism. PMID:27169421

Roles of renal ammonia metabolism other than in acid-base homeostasis.

PubMed

Weiner, I David

2017-06-01

The importance of renal ammonia metabolism in acid-base homeostasis is well known. However, the effects of renal ammonia metabolism other than in acid-base homeostasis are not as widely recognized. First, ammonia differs from almost all other solutes in the urine in that it does not result from arterial delivery. Instead, ammonia is produced by the kidney, and only a portion of the ammonia produced is excreted in the urine, with the remainder returned to the systemic circulation through the renal veins. In normal individuals, systemic ammonia addition is metabolized efficiently by the liver, but in patients with either acute or chronic liver disease, conditions that increase the addition of ammonia of renal origin to the systemic circulation can result in precipitation and/or worsening of hyperammonemia. Second, ammonia appears to serve as an intrarenal paracrine signaling molecule. Hypokalemia increases proximal tubule ammonia production and secretion as well as reabsorption in the thick ascending limb of the loop of Henle, thereby increasing delivery to the renal interstitium and the collecting duct. In the collecting duct, ammonia decreases potassium secretion and stimulates potassium reabsorption, thereby decreasing urinary potassium excretion and enabling feedback correction of the initiating hypokalemia. Finally, the stimulation of renal ammonia metabolism by hypokalemia may contribute to the development of metabolic alkalosis, which in turn can stimulate NaCl reabsorption and contribute to the intravascular volume expansion, increased blood pressure and diuretic resistance that can develop with hypokalemia. The evidence supporting these novel non-acid-base roles of renal ammonia metabolism is discussed in this review.

Maturation of the renal response to hypertonic sodium chloride loading in rats: micropuncture and clearance studies.

PubMed Central

Baker, J T; Solomon, S

1976-01-01

1. The ability of maturing rats to excrete a sodium load was studied by micropuncture and clearance procedures. 2. During control conditions, no change of glomerular filtration rate or sodium excretion was observed for the time period of the entire procedure (P greater than 0-20). During the infusion of hypertonic (4%) sodium chloride, fractional sodium excretion was 0-08 +/- 0-01 in rats 21-30 days old and 0-14 +/- 0-01 (P less than 0-01) in adults. However, the depression of proximal tubular water re-absorption was equal in both groups (P greater than 0-20). 3. Proximal glomerulotubular balance for water re-absorption was similar in all groups (P less than 0-20). Since end proximal tubular water excretion and depression of fractional water excretion were the same in all animals, differences of urinary sodium excretion during development are probably due to differences of function of segments beyond the proximal tubule during development. 4. Fractional potassium excretion was reduced in young rats (0-17 +/- 0-04) during hypertonic sodium chloride infusion, compared to adults (0-24 +/- 0-01, P less than 0-05). 5. Passage time of fast green through cortical segments in seconds is prolonged in young rats during control conditions. Similar decreases of passage time were seen in all groups during hypertonic sodium chloride infusion. No segmental differences of passage time were seen during developmental. 6. No difference in the relationship between fractional sodium and water excretion was seen during development of the renal response to hypertonic sodium chloride infusion. Thus, altered sensitivity to sodium chloride osmotic diuresis does not exist during maturation in rats. PMID:945839

Systematic review and meta-analysis of randomised controlled trials on the effects of potassium supplements on serum potassium and creatinine.

PubMed

Cappuccio, Francesco P; Buchanan, Laura A; Ji, Chen; Siani, Alfonso; Miller, Michelle A

2016-08-26

High potassium intake could prevent stroke, but supplementation is considered hazardous. We assessed the effect of oral potassium supplementation on serum or plasma potassium levels and renal function. We updated a systematic review of the effects of potassium supplementation in randomised clinical trials carried out worldwide, published in 2013, extending it to July 2015. We followed the PRISMA guidelines. Any individual taking part in a potassium supplementation randomised clinical trial. Studies included met the following criteria: randomised clinical trials, potassium supplement given and circulating potassium levels reported. Oral potassium supplementation. Serum or plasma potassium and serum or plasma creatinine. A total of 20 trials (21 independent groups) were included (1216 participants from 12 different countries). All but 2 were controlled (placebo n=16, control n=2). Of these trials, 15 were crossover, 4 had a parallel group and 1 was sequential. The duration of supplementation varied from 2 to 24 weeks and the amount of potassium given from 22 to 140 mmol/day. In the pooled analysis, potassium supplementation caused a small but significant increase in circulating potassium levels (weighted mean difference (WMD) 0.14 mmol/L, 95% CI 0.09 to 0.19, p<1×10(-5)), not associated with dose or duration of treatment. The average increase in urinary potassium excretion was 45.75 mmol/24 hours, 95% CI 38.81 to 53.69, p<1×10(-5). Potassium supplementation did not cause any change in circulating creatinine levels (WMD 0.30 µmol/L, 95% CI -1.19 to 1.78, p=0.70). In short-term studies of relatively healthy persons, a moderate oral potassium supplement resulted in a small increase in circulating potassium levels and no change in renal function. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Controlled exercise effects on chromium excretion of trained and untrained runners consuming a constant diet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, R.A.; Bryden, N.A.; Polansky, M.M.

1986-03-05

To determine if degree of training effects urinary Cr losses, Cr excretion of 8 adult trained and 5 untrained runners was determined on rest days and following exercise at 90% of maximal oxygen uptake on a treadmill to exhaustion with 30 second exercise and 30 second rest periods. Subjects were fed a constant daily diet containing 9 ..mu..g of Cr per 1000 calories to minimize changes due to diet. Maximal oxygen consumption of the trained runners was in the good or above range based upon their age and that of the untrained runners was average or below. While consuming themore » control diet, basal urinary Cr excretion of subjects who exercise regularly was significantly lower than that of the sedentary control subjects, 0.09 +/- 0.01 and 0.21 +/- 0.03 ..mu..g/day (mean +/- SEM), respectively. Daily urinary Cr excretion of trained subjects was significantly higher on the day of a single exercise bout at 90% of maximal oxygen consumption compared to nonexercise days, 0.12 +/- 0.02 and 0.09 +/- 0.01 ..mu..g/day, respectively. Urinary Cr excretion of 5 untrained subjects was not altered following controlled exercise. These data demonstrate that basal urinary Cr excretion and excretion in response to exercise are related to maximal oxygen consumption and therefore degree of fitness.« less

Low-grade albuminuria reduction with angiotensin II type 1 receptor blocker in renal transplant recipients.

PubMed

Uchida, Junji; Machida, Yuichi; Iwai, Tomoaki; Iguchi, Taro; Kamada, Yoshiko; Naganuma, Toshihide; Kumada, Norihiko; Kim, Taku; Kawashima, Hidenori; Nakatani, Tatsuya

2011-01-01

Microalbuminuria, defined as urine albumin to urine creatinine ratio of 30 to <300 mg/g, is an established risk factor for cardiovascular morbidity and mortality in the general population. Low-grade albuminuria (<30 mg/g) is considered a marker for subclinical vascular damage that predisposes to future cardiovascular diseases and death. Lowering urinary albumin excretion reduces the risk of cardiovascular disease. Our study was designed to evaluate the influence of angiotensin II type 1 receptor blocker (ARB) in normotensive renal transplant recipients with low-grade albuminuria. Our 6-month prospective observation study used a randomized control and open-label design as we examined the effects of an ARB (valsartan) on blood pressure, urinary albumin excretion, hematocrit, serum potassium and estimated glomerular filtration rate (eGFR) in normotensive recipients with allografts of more than 1 year. A total of 35 renal transplant recipients were enrolled in this study. Patients were randomly assigned to 2 groups: ARB group (n=18), receiving 40-80 mg valsartan daily for 6 months, and the control group (n=17). In the ARB group, urine albumin excretion was significantly reduced from 25.9 ± 19.1 mg/g to 12.0 ± 9.6 mg/g at 6 months after administration. eGFR decreased slightly at 6 months after administration. However, no patients undergoing treatment for adverse effects required discontinuation of ARB. This study reveals that ARB is safe and reduces low-grade albuminuria in normotensive renal transplant recipients. Thus, early treatment of ARB in recipients with low-grade albuminuria may prevent cardiovascular disease after renal transplantation.

COMPARISON OF THE URINARY METABOLITES OF RATS, MICE, AND HUMANS AFTER ORAL ARSENIC EXPOSURE FOCUSING ON THIOARSENICALS

EPA Science Inventory

Urinary metabolites of arsenic are useful as biomarkers of exposure because ingested arsenic is excreted primarily in urine1. Complete urinary arsenic speciation can provide insight into possible metabolic pathways as well as potential exposure sources. The pattern of excreted me...

Urinary Fluoride Concentration in Children with Disabilities Following Long-Term Fluoride Tablet Ingestion

ERIC Educational Resources Information Center

Liu, Hsiu-Yueh; Chen, Jung-Ren; Hung, Hsin-Chia; Hsiao, Szu-Yu; Huang, Shun-Te; Chen, Hong-Sen

2011-01-01

Urine is the most commonly utilized biomarker for fluoride excretion in public health and epidemiological studies. Approximately 30-50% of fluoride is excreted from urine in children. Urinary fluoride excretion reflects the total fluoride intake from multiple sources. After administering fluoride tablets to children with disabilities, urinary…

Urinary isoflavonoid excretion as a biomarker of dietary soy intake during two randomized soy trials

PubMed Central

Morimoto, Yukiko; Beckford, Fanchon; Franke, Adrian A.; Maskarinec, Gertraud

2014-01-01

We evaluated urinary isoflavonoid excretion as a biomarker of dietary isoflavone intake during two randomized soy trials (13–24 months) among 256 premenopausal women with a total of 1,385 repeated urine samples. Participants consumed a high-soy diet (2 servings/day) and a low-soy diet (<3 servings/week), completed 7 unannounced 24-hour dietary recalls, and donated repeated urine samples, which were analyzed for isoflavonoid excretion by liquid chromatography methods. We computed correlation coefficients and applied logistic regression to estimate the area under the curve. Median daily dietary isoflavone intakes at baseline, during low- and high-soy diet were 0.5, 0.2, and 67.7 mg aglycone equivalents, respectively. The corresponding urinary isoflavonoid excretion values were 0.9, 1.1, and 43.9 nmol/mg creatinine. Across diets, urinary isoflavonoid excretion was significantly associated with dietary isoflavone intake (rs=0.51, AUC=0.85; p<0.0001) but not within diet periods (rs=0.05–0.06, AUC=0.565–0.573). Urinary isoflavonoid excretion is an excellent biomarker to discriminate between low- and high-soy diets across populations, but the association with dietary isoflavone intake is weak when the range of soy intake is small. PMID:24901088

Marked increase in urinary excretion of apolipoproteins in children with nephrolithiasis associated with hypercalciuria.

PubMed

Kovacevic, Larisa; Lu, Hong; Caruso, Joseph A; Govil-Dalela, Tuhina; Thomas, Ronald; Lakshmanan, Yegappan

2017-06-01

Using a proteomic approach, we aimed to identify and compare the urinary excretion of proteins involved in lipid transport and metabolism in children with kidney stones and hypercalciuria (CAL), hypocitraturia (CIT), and normal metabolic work-up (NM), and in healthy controls (HCs). Additionally, we aimed to confirm these results using ELISA, and to examine the relationship between the urinary excretion of selected proteins with demographic, dietary, blood, and urinary parameters. Prospective, controlled, pilot study of pooled urine from CAL, CIT, and NM versus age- and gender-matched HCs, using liquid chromatography-mass spectrometry. Relative protein abundance was estimated using spectral counting. Results were confirmed by ELISA performed on individual samples. Of the 1,813 proteins identified, 230 met the above criteria. Of those, 5 proteins (apolipoprotein A-II [APOA2]; apolipoprotein A-IV [APOA4]; apolipoprotein C-III [APOA3]; fatty acid-binding protein, liver [FABPL]; fatty acid-binding protein, adipocyte [FABP4]) involved in lipid metabolism and transport were found in the CAL group, with significant differences compared with HCs. ELISA analysis indicated statistically significant differences in the urinary excretion of APOC3, APOA4, and FABPL in the CAL group compared with HCs. Twenty-four-hour urinary calcium excretion correlated significantly with concentrations of ApoC3 (r = 0.77, p < 0.001), and FABPL (r = 0.80, p = 0.005). We provide proteomic data showing increased urinary excretion of lipid metabolism/transport-related proteins in children with kidney stones and hypercalciuria. These findings suggest that abnormalities in lipid metabolism might play a role in kidney stone formation.

Effect of fasting on the urinary excretion of water-soluble vitamins in humans and rats.

PubMed

Fukuwatari, Tsutomu; Yoshida, Erina; Takahashi, Kei; Shibata, Katsumi

2010-01-01

Recent studies showed that the urinary excretion of the water-soluble vitamins can be useful as a nutritional index. To determine how fasting affects urinary excretion of water-soluble vitamins, a human study and an animal experiment were conducted. In the human study, the 24-h urinary excretion of water-soluble vitamins in 12 healthy Japanese adults fasting for a day was measured. One-day fasting drastically decreased urinary thiamin content to 30%, and increased urinary riboflavin content by 3-fold. Other water-soluble vitamin contents did not show significant change by fasting. To further investigate the alterations of water-soluble vitamin status by starvation, rats were starved for 3 d, and water-soluble vitamin contents in the liver, blood and urine were measured during starvation. Urinary excretion of thiamin, riboflavin, vitamin B(6) metabolite 4-pyridoxic acid, nicotinamide metabolites and folate decreased during starvation, but that of vitamin B(12), pantothenic acid and biotin did not. As for blood vitamin levels, only blood vitamin B(1), plasma PLP and plasma folate levels decreased with starvation. All water-soluble vitamin contents in the liver decreased during starvation, whereas vitamin concentrations in the liver did not decrease. Starvation decreased only concentrations of vitamin B(12) and folate in the skeletal muscle. These results suggest that water-soluble vitamins were released from the liver, and supplied to the peripheral tissues to maintain vitamin nutrition. Our human study also suggested that the effect of fasting should be taken into consideration for subjects showing low urinary thiamin and high urinary riboflavin.

Urinary excretion of 5-hydroxyindoleacetic acid, serotonin and 6-sulphatoxymelatonin in normoserotonemic and hyperserotonemic autistic individuals.

PubMed

Mulder, Erik J; Anderson, George M; Kemperman, Ramses F J; Oosterloo-Duinkerken, Alida; Minderaa, Ruud B; Kema, Ido P

2010-01-01

A substantial proportion of individuals with autism have elevated levels of platelet serotonin (5-HT). We examined whether platelet hyperserotonemia is associated with increased gut 5-HT synthesis, altered 5-HT catabolism or altered melatonin production. Urinary excretion of 5-hydroxyindoleacetic acid (5-HIAA) and 5-HT was compared in 10 normoserotonemic and 10 hyperserotonemic age-matched autistic individuals. The relationship of urinary 6-sulfatoxymelatonin (6-SM) excretion to platelet 5-HT, and to urinary 5-HT and 5-HIAA excretion, was also examined. In the hyperserotonemic group, significant increases at trend level in urinary excretion of 5-HIAA (p = 0.061) and 5-HT (p = 0.071) and a significant decrease for 6-SM were found (p = 0.027). The urinary 5-HIAA:5-HT ratio was similar in the normo- versus the hyperserotonemic groups. The catabolism of 5-HT does not differ in the groups, but greater exposure of the platelet to 5-HT cannot be ruled out as a cause of the platelet hyperserotonemia of autism. Although only trend level significant, the data point to a need for larger studies to examine more thoroughly the relationships between platelet hyperserotonemia, gut 5-HT synthesis and melatonin production. (c) 2009 S. Karger AG, Basel.

Effect of monofluoroacetate on renal H+ excretion in the rat.

PubMed

Simonnet, H; Gauthier, C; Pellet, M V

1979-05-01

In order to investigate the effect of monofluoroacetate (MFA) on renal H+ excretion, anesthetized rats under mannitol diuresis were given intraperitoneally MFA and some of the acido-basic status parameters were determined. Urinary pH and pCO2 did not change after MFA administration, while urinary flow rate increased. MFA induced a decrease in H+ net excretion and in ammonia excretion. Titratable acidity did not change significantly within the experiment.

Effect of urinary pH and nicotine excretion rate on plasma nicotine during cigarette smoking and chewing nicotine gum

PubMed Central

Feyerabend, C.; Russell, M. A. H.

1978-01-01

1 Plasma nicotine levels produced by chewing nicotine gum were compared with those obtained by cigarette smoking under conditions of controlled urinary pH. 2 Although absorption was slower, plasma levels comparable to cigarette smoking were built up on 4 mg (but not 2 mg) nicotine gum. 3 Urinary excretion of nicotine was influenced markedly by pH and the rate of urine flow. 4 Plasma nicotine was higher under alkaline compared to acidic conditions (P < 0.001) but the rate of urinary nicotine excretion appeared to have little effect on the plasma level.

Extreme urinary betaine losses in type 2 diabetes combined with bezafibrate treatment are associated with losses of dimethylglycine and choline but not with increased losses of other osmolytes.

PubMed

Lever, Michael; McEntyre, Christopher J; George, Peter M; Slow, Sandy; Elmslie, Jane L; Lunt, Helen; Chambers, Stephen T; Parry-Strong, Amber; Krebs, Jeremy D

2014-10-01

Betaine deficiency is a probable cardiovascular risk factor and a cause of elevated homocysteine. Urinary betaine excretion is increased by fibrate treatment, and is also often elevated in diabetes. Does fibrate further increase betaine excretion in diabetes, and does it affect the plasma concentrations and excretions of related metabolites and of other osmolytes? Samples from a previous study of type 2 diabetes were selected if participants were taking bezafibrate (n = 32). These samples were compared with participants matched for age and gender and not on a fibrate (comparator group, n = 64). Betaine, related metabolites, and osmolytes were measured in plasma and urine samples from these 96 participants. Median urinary betaine excretion in those on bezafibrate was 5-fold higher than in the comparator group (p < 0.001), itself 3.5-fold higher than the median reported for healthy populations. In the bezafibrate group, median dimethylglycine excretion was higher (9-fold, p < 0.001). Excretions of choline, and of the osmolytes myo-inositol, taurine and glycerophosphorylcholine, were not significantly different between groups. Some participants excreted more betaine than usual dietary intakes. Several betaine fractional clearances were >100 %. Betaine excretion correlated with excretions of the osmolytes myo-inositol and glycerophosphorylcholine, and also with the excretion of choline and N,N-dimethylglycine, but it was inconclusive whether these relationships were affected by bezafibrate therapy. Increased urinary betaine excretions in type 2 diabetes are further increased by fibrate treatment, sometimes to more than their dietary intake. Concurrent betaine supplementation may be beneficial.

Renal effects of continuous negative pressure breathing

NASA Technical Reports Server (NTRS)

Kinney, M. J.

1975-01-01

Continuous negative pressure breathing (CNPB) was utilized to simulate the thoracic vascular distension of zero G in 11 anesthetized rats. The animals underwent renal clearance and micropuncture renal nephron studies before, during, and after CNPB. Four rats were pretreated with a high salt diet and I-M desoxycorticosterone (DOCA) in excess. None of these rats diuresed with CNPB. In contrast, five of the seven remaining rats increased the fraction of the filtered sodium excreted and their urinary flow rate. Potassium excretion increased. End proximal tubular fluid specimen's TF/P inulin ratios were unchanged. Whole kidney and single nephron glomerular filtration rates fell 10%. CNPB, a mechanism for atrial distension, appears to cause in the rat a decrease in distal tubular sodium and water reabsorption. Exogenous mineral-corticoid prevents the diuresis, saluresis, and kaluresis. The adequacy of other nonatrial volume control mechanisms in regulating renal salt and water conservation in opposition to the studied atrial-renal (Henry-Gauer) reflex of thoracic vascular distension is confirmed.

Carnitine status in Thai adults.

PubMed

Tanphaichitr, V; Lerdvuthisopon, N; Dhanamitta, S; Broquist, H P

1980-04-01

Plasma carnitine and urinary carnitine levels were measured in Thai adults living in Bangkok city and Ubol villages. The mean plasma carnitine and urinary carnitine levels expressed in micromoles per liter in Bangkok adults were higher than those in Ubol adults. Their mean plasma carnitine levels were 56.6 +/- 1.8 and 50.3 +/- 1.7 whereas urinary carnitine levels were 161 +/- 19 and 127 +/- 18 micromole/liter, respectively. The nutritional status in Ubol adults was inadequate. This was evidenced by the significant decrease in urinary creatinine excretion, serum albumin, and hematocrit levels. The dietary assessment agreed with the biochemical findings. Since rice, limiting in carnitine, was the main protein and energy source consumed by Ubol adults their inadequate carnitine status could be due to the low carnitine intake. Sex affects plasma carnitine levels in Bangkok adults and urinary carnitine excretion in both groups. This could be related to the lean body mass in which most of the body carnitine resides. This is supported by the higher urinary creatinine excretion in males and the significant positive correlation between carnitine excretion and creatinine-height index.

Effects of pressure on the skin exerted by clothing on responses of urinary catecholamines and cortisol, heart rate and nocturnal urinary melatonin in humans

NASA Astrophysics Data System (ADS)

Mori, Yuki; Kioka, Etsuko; Tokura, Hiromi

2002-09-01

The study investigated how the pressure exerted on the skin by clothing worn while working in the daytime affected the urinary excretion of adrenaline, noradrenaline and cortisol, heart rate, and also melatonin secretion at night. Nine young women (experiment I) and seven young women (experiment II) participated. Participants wore either a 100% cotton jacket (tight clothes, TC) or a 100% cotton T-shirt (loose clothes, LC). Loose-fitting, 100% cotton tank tops and panties were worn as underwear in both the TC and the LC groups. The main results can be summarized as follows: (1) urinary excretion of adrenaline, noradrenaline and cortisol was facilitated, and the amounts of urinary excretion were significantly higher when TC were worn. Heart rate was significantly higher in the TC group; (2) nocturnal urinary melatonin excretion was significantly greater in the TC group. These results are discussed in terms of an enhancement of diurnal sympathetic nervous system activity caused by pressure on the skin produced by tight clothing.

The effects of infusions of ring-A-reduced derivatives of aldosterone on the antinatriuretic and kaliuretic actions of aldosterone.

PubMed

Morris, D J; Souness, G W; Saccoccio, N A; Harnik, M

1989-01-01

Infusion of Ring-A-reduced metabolites of aldosterone in adrenalectomized male rats for 4 days revealed that 5 alpha-Ring-A-reduced derivatives, 5 alpha-dihydroaldosterone (5 alpha-DHAldo; 2.5-5.0 micrograms/day), 3 alpha,5 alpha-tetrahydroaldosterone (3 alpha,5 alpha-THAldo; 5-25 micrograms/day), and 3 beta,5 alpha-THAldo (50-175 micrograms/day) possessed intrinsic Na+-retaining activity. The same infusions of 5 alpha-DHAldo, 3 alpha,5 alpha-THAldo, and 3 beta,5 alpha-THAldo, also lowered the urinary excretion of potassium. The 5 beta-Ring-A-reduced derivative 3 alpha,5 beta-THAldo did not demonstrate either of these biological properties. In another set of experiments, on the fourth day of infusion, aldosterone (0.1 microgram/rat) was administered acutely subcutaneously; none of the Ring-A-reduced derivatives altered the Na+-retaining activity of aldosterone. However, in a dose-dependent manner, both 3 alpha,5 alpha-THAldo and 3 beta,5 alpha-THAldo blunted the urinary K+-secretory effect of aldosterone; low dosages of 5 alpha-DHAldo and larger dosages of 3 alpha,5 beta-THAldo did not. Thus, the 5 alpha-reduced derivatives of aldosterone not only lowered urinary Na+ and K+ excretion in their own right, but two of them blunted the kaliuretic response of the parent mineralocorticoid, aldosterone. Further experiments will be required to determine whether these aldosterone metabolites are further metabolized or interconverted during the expression of the regulatory properties described here and whether these properties are physiologically relevant.

Application of path analysis to urinary findings of cadmium-induced renal dysfunction.

PubMed

Abe, T; Kobayashi, E; Okubo, Y; Suwazono, Y; Kido, T; Shaikh, Z A; Nogawa, K

2001-01-01

In order to identify some causal relations among various urinary indices of cadmium-induced renal dysfunction, such as glucose, total protein, amino nitrogen, beta 2-microglobulin (beta 2-m), metallothionein (MT), and cadmium (Cd), we applied path analysis method to previous epidemiological studies targeting the residents of the Cd-polluted Kakehashi River basin of Ishikawa Prefecture, Japan. We obtained a diagram-termed path model, representing some causal relations among the above urinary indices. It shows that urinary Cd is located at the beginning point in the diagram, and Cd-induced renal dysfunction develops in the following order: Cd exposure-->increase of beta 2-m and/or MT excretion-->increase of amino-N and/or total protein excretion-->increase of glucose excretion. It was proved mathematically, that in the case of both males and females, increased excretions of beta 2-m and/or MT were the most sensitive urinary indices of the early stage of chronic Cd-induced renal dysfunction.

A multiregional Italian cohort of 24-hour urine metabolic evaluation in renal stone formers.

PubMed

Esperto, Francesco; Marangella, Martino; Trinchieri, Alberto; Petrarulo, Michele; Miano, Roberto

2018-02-01

Nephrolithiasis is a common condition with several studies documenting an increased prevalence over the past four decades. EAU and AUA guidelines recommend 24-hour urine metabolic evaluation in high-risk stone formers. Aim of this study is to retrospectively evaluate the first three years of experience with LithoTest® (Biohealth Italia Srl, Turin, Italy) through the analysis of demographic, clinical and biochemical data collected from a large cohort of patients with kidney stones. We retrospectively analyzed data from the LithoCenter database, including data from outpatient consultations, between January 2007 and December 2009 from all over Italy. LithoTest® was performed through a 24-hour urine collection and included measurements of urine volume and pH, 24-hour excretion of creatinine as well as main cations and anions, including calcium, magnesium sodium potassium, ammonium, uric acid, oxalate, citrate, phosphate, inorganic sulphate and chloride. Urine state of saturation for calcium oxalate (βCaOx), calcium hydrogen phosphate or brushite (βbsh) and uric acid (βUA) were also calculated by means of the computer program LithoRisk. Brand's test for cystinuria was also carried out. Statistical analysis was performed using the S-PSS software v. 22.0. The number of patients with data available for analysis was 435, of whom 236 were male (54%) and 199 female (46%). Complete 24-hour urine measurements were available for all 435 patients. Compared to men, women had significantly lower values for creatinine, urate, oxalate, phosphate, sodium, potassium, magnesium and chloride excretion, whereas 24-hour pH and citrate excretion were higher. No significant differences were found for the other examined variables. βCaOx and βUA were significantly higher in men than women, whereas no significant difference was found for βbsh. There was a direct relationship between calcium and sodium urine excretion. Excessive sodium excretion was recorded in 191 patients (44%) and low urine volumes in 201 (46.2%). Hyperoxaluria was observed in 118 patients (27.3%), hypercalciuria in 115 (26.6%), hyperuricosuria in 153 (35.4%), hypomagnesuria in 96 (22.2%), and hypocitraturia in 134 patients (31%). Hyperexcretion of sodium, hypocitraturia and hyperoxaluria were most frequent in males. βCaOx was significantly higher in the setting of hypercalciuria, hypocitraturia, hyperoxaluria and urine pH below 5.5. Our findings in a large cohort of high-risk stone-forming patients show significant differences in urinary metabolic profiles between men and women. Carrying on the collection and analysis of data by LithoTest® from 2009 to 2015 and matching urinary and dietary data could eventually improve our understanding on the metabolic profile of stone-formers in Italy.

Behavior of heavy metals in human urine and blood following calcium disodium ethylenediamine tetraacetate injection: observations in metal workers.

PubMed

Sata, F; Araki, S; Murata, K; Aono, H

1998-06-12

To evaluate the effects of calcium disodium ethylenediamine tetraacetate (CaEDTA) on the behavior of 8 heavy metals in human urine and blood, CaEDTA was administered for 1 h by intravenous injection to 18 male metal foundry workers, whose blood lead concentrations (PbB) were between 16 and 59 (mean 34) microg/dl. Significant increases were found in urinary excretion of manganese, chromium, lead, zinc, and copper after the start of CaEDTA injection. Urinary chromium excretion reached a maximal level within 1 h after the start of injection, while urinary manganese, lead, and zinc excretion reached their highest concentrations between 1 and 2 h. Urinary copper excretion reached the highest level between 2 and 4 h. The rapid increases in urinary excretion of five metals were different from the "circadian rhythms," which are the normal, daily variations in renal glomerular filtration, reabsorption, and excretory mechanisms. Plasma lead concentrations were highest 1.5 h after the start of the 1-h injection, while plasma zinc concentration became lowest 5 h after the start of CaEDTA injection. Data suggest that manganese and chromium absorbed in human tissues might be mobilized by CaEDTA.

Self-monitoring urinary salt excretion in adults: A novel education program for restricting dietary salt intake

PubMed Central

YASUTAKE, KENICHIRO; SAWANO, KAYOKO; YAMAGUCHI, SHOKO; SAKAI, HIROKO; AMADERA, HATSUMI; TSUCHIHASHI, TAKUYA

2011-01-01

This study aimed to examine the usefulness of the self-monitoring of urinary salt excretion for educating individuals about the risk of excessive dietary salt intake. The subjects were 30 volunteers (15 men and 15 women) not consuming anti-hypertensive medication. The subjects measured urinary salt excretion at home for 4 weeks using a self-monitoring device. Blood pressure (BP), anthropometric variables and nutritional variables (by a dietary-habits questionnaire) were measured before and after the measurement of urinary salt excretion. Statistical analyses were performed, including paired t-tests, Chi-square test, Pearson’s product moment correlation coefficient and multiple linear regression analysis. In all subjects, the average urinary salt excretion over 4 weeks was 8.05±1.61 g/day and the range (maximum-minimum value) was 5.58±2.15 g/day. Salt excretion decreased significantly in weeks 3 and 4 (P<0.05 and P<0.01, respectively). Diastolic BP decreased from 77.7±14.3 (at baseline) to 74.3±13.3 after 4 weeks (P<0.05), while systolic BP and anthropometric variables remained unchanged. Nutrition surveys indicated that energy intake was correlated with salt intake both before and after the measurements; changes in both variables during the observation period were correlated (r=0.40, P<0.05). The percentage of subjects who were aware of the restriction in dietary salt intake increased from 47 to 90%. In conclusion, daily monitoring of the amount of urinary salt excretion using a self-monitoring device appears to be an effective educational tool for improving the quality of life of healthy adults. PMID:22977549

Self-monitoring urinary salt excretion in adults: A novel education program for restricting dietary salt intake.

PubMed

Yasutake, Kenichiro; Sawano, Kayoko; Yamaguchi, Shoko; Sakai, Hiroko; Amadera, Hatsumi; Tsuchihashi, Takuya

2011-07-01

This study aimed to examine the usefulness of the self-monitoring of urinary salt excretion for educating individuals about the risk of excessive dietary salt intake. The subjects were 30 volunteers (15 men and 15 women) not consuming anti-hypertensive medication. The subjects measured urinary salt excretion at home for 4 weeks using a self-monitoring device. Blood pressure (BP), anthropometric variables and nutritional variables (by a dietary-habits questionnaire) were measured before and after the measurement of urinary salt excretion. Statistical analyses were performed, including paired t-tests, Chi-square test, Pearson's product moment correlation coefficient and multiple linear regression analysis. In all subjects, the average urinary salt excretion over 4 weeks was 8.05±1.61 g/day and the range (maximum-minimum value) was 5.58±2.15 g/day. Salt excretion decreased significantly in weeks 3 and 4 (P<0.05 and P<0.01, respectively). Diastolic BP decreased from 77.7±14.3 (at baseline) to 74.3±13.3 after 4 weeks (P<0.05), while systolic BP and anthropometric variables remained unchanged. Nutrition surveys indicated that energy intake was correlated with salt intake both before and after the measurements; changes in both variables during the observation period were correlated (r=0.40, P<0.05). The percentage of subjects who were aware of the restriction in dietary salt intake increased from 47 to 90%. In conclusion, daily monitoring of the amount of urinary salt excretion using a self-monitoring device appears to be an effective educational tool for improving the quality of life of healthy adults.

Adult presentation of Bartter syndrome type IV with erythrocytosis.

PubMed

Heilberg, Ita Pfeferman; Tótoli, Cláudia; Calado, Joaquim Tomaz

2015-01-01

Bartter syndrome comprises a group of rare autosomal-recessive salt-losing disorders with distinct phenotypes, but one unifying pathophysiology consisting of severe reductions of sodium reabsorption caused by mutations in five genes expressed in the thick ascending limb of Henle, coupled with increased urinary excretion of potassium and hydrogen, which leads to hypokalemic alkalosis. Bartter syndrome type IV, caused by loss-of-function mutations in barttin, a subunit of chloride channel CLC-Kb expressed in the kidney and inner ear, usually occurs in the antenatal-neonatal period. We report an unusual case of late onset presentation of Bartter syndrome IV and mild phenotype in a 20 years-old man who had hypokalemia, deafness, secondary hyperparathyroidism and erythrocytosis.

Human urinary excretion profile after smoking and oral administration of ( sup 14 C)delta 1-tetrahydrocannabinol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johansson, E.; Gillespie, H.K.; Halldin, M.M.

The urinary excretion profiles of delta 1-tetrahydrocannabinol (delta 1-THC) metabolites have been evaluated in two chronic and two naive marijuana users after smoking and oral administration of ({sup 14}C)delta 1-THC. Urine was collected for five days after each administration route and analyzed for total delta 1-THC metabolites by radioactivity determination, for delta 1-THC-7-oic acid by high-performance liquid chromatography, and for cross-reacting cannabinoids by the EMIT d.a.u. cannabinoid assay. The average urinary excretion half-life of {sup 14}C-labeled delta 1-THC metabolites was calculated to be 18.2 +/- 4.9 h (+/- SD). The excretion profiles of delta 1-THC-7-oic acid and EMIT readings weremore » similar to the excretion profile of {sup 14}C-labeled metabolites in the naive users. However, in the chronic users the excretion profiles of delta 1-THC-7-oic acid and EMIT readings did not resemble the radioactive excretion due to the heavy influence from previous Cannabis use. Between 8-14% of the radioactive dose was recovered in the urine in both user groups after oral administration. Lower urinary recovery was obtained both in the chronic and naive users after smoking--5 and 2%, respectively.« less

Associations of Biomarker-Calibrated Sodium and Potassium Intakes With Cardiovascular Disease Risk Among Postmenopausal Women.

PubMed

Prentice, Ross L; Huang, Ying; Neuhouser, Marian L; Manson, JoAnn E; Mossavar-Rahmani, Yasmin; Thomas, Fridtjof; Tinker, Lesley F; Allison, Matthew; Johnson, Karen C; Wassertheil-Smoller, Sylvia; Seth, Arjun; Rossouw, Jacques E; Shikany, James; Carbone, Laura D; Martin, Lisa W; Stefanick, Marcia L; Haring, Bernhard; Van Horn, Linda

2017-11-01

Studies of the associations of sodium and potassium intakes with cardiovascular disease incidence often rely on self-reported dietary data. In the present study, self-reported intakes from postmenopausal women at 40 participating US clinical centers are calibrated using 24-hour urinary excretion measures in cohorts from the Women's Health Initiative, with follow-up from 1993 to 2010. The incidence of hypertension was positively related to (calibrated) sodium intake and to the ratio of sodium to potassium. The sodium-to-potassium ratio was associated with cardiovascular disease incidence during an average follow-up period of 12 years. The estimated hazard ratio for a 20% increase in the sodium-to-potassium ratio was 1.13 (95% confidence interval (CI): 1.04, 1.22) for coronary heart disease, 1.20 (95% CI: 1.01, 1.42) for heart failure, and 1.11 (95% CI: 1.04, 1.19) for a composite cardiovascular disease outcome. The association with total stroke was not significant, but it was positive for ischemic stroke and inverse for hemorrhagic stroke. Aside from hemorrhagic stroke, corresponding associations of cardiovascular disease with sodium and potassium jointly were positive for sodium and inverse for potassium, although some were not statistically significant. Specifically, for coronary heart disease, the hazard ratios for 20% increases were 1.11 (95% CI: 0.95, 1.30) for sodium and 0.85 (95% CI: 0.73, 0.99) for potassium; and corresponding values for heart failure were 1.36 (95% CI: 1.02, 1.82) for sodium and 0.90 (95% CI: 0.69, 1.18) for potassium. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Reproducibility of blood pressure responses to dietary sodium and potassium interventions: the GenSalt study.

PubMed

Gu, Dongfeng; Zhao, Qi; Chen, Jing; Chen, Ji-Chun; Huang, Jianfeng; Bazzano, Lydia A; Lu, Fanghong; Mu, Jianjun; Li, Jianxin; Cao, Jie; Mills, Katherine; Chen, Chung-Shiuan; Rice, Treva; Hamm, L Lee; He, Jiang

2013-09-01

Blood pressure responses to dietary sodium and potassium interventions vary among individuals. We studied the long-term reproducibility of blood pressure responses to dietary sodium and potassium intake. We repeated the dietary sodium and potassium interventions among 487 Chinese adults 4.5 years after the original dietary intervention. The identical dietary intervention protocol, which included a 7-day low-sodium feeding (51.3 mmol/d), a 7-day high-sodium feeding (307.8 mmol/d), and a 7-day high-sodium feeding with oral potassium supplementation (60.0 mmol/d), was applied in both the initial and repeated studies. Three blood pressure measurements were obtained during each of the 3 days of baseline observation and on days 5, 6, and 7 of each intervention period. The results from the 24-hour urinary excretion of sodium and potassium showed excellent compliance with the study diet. Blood pressure responses to dietary intervention in the original and repeated studies were highly correlated. For example, the correlation coefficients (95% confidence interval) for systolic blood pressure levels were 0.77 (0.73-0.80) at baseline, 0.79 (0.75-0.82) during low sodium, 0.80 (0.77-0.83) during high sodium, and 0.82 (0.79-0.85) during high sodium and potassium supplementation interventions (all P<0.0001). The correlation coefficients for systolic blood pressure changes were 0.37 (0.29-0.44) from baseline to low sodium, 0.37 (0.29-0.44) from low to high sodium, and 0.28 (0.20-0.36) from high sodium to high sodium plus potassium supplementation (all P<0.0001). These data indicate that blood pressure responses to dietary sodium and potassium interventions have long-term reproducibility and stable characteristics in the general population.

Cytomegalovirus urinary excretion and long term outcome in children with congenital cytomegalovirus infection. Congenital CMV Longitudinal Study Group.

PubMed

Noyola, D E; Demmler, G J; Williamson, W D; Griesser, C; Sellers, S; Llorente, A; Littman, T; Williams, S; Jarrett, L; Yow, M D

2000-06-01

Cytomegalovirus (CMV) is the most frequent cause of congenital infection, and both symptomatic and asymptomatic infants may have long term sequelae. Children with congenital CMV infection are chronically infected and excrete CMV in the urine for prolonged periods. However, the effect of prolonged viral replication on the long term outcome of these children is unknown. To determine whether duration of CMV excretion is associated with outcome at 6 years of life in symptomatic and asymptomatic congenitally infected children. Longitudinal cohort study. Children congenitally infected with CMV were identified at birth and followed prospectively in a study of long term effects of congenital CMV infection. The relationship between duration of CMV urinary excretion and growth, neurodevelopment and presence and progression of sensorineural hearing loss (SNHL) at 6 years of age was determined. There was no significant difference in the duration of viral urinary excretion between children born with asymptomatic (median, 4.55 years) and symptomatic (median, 2.97 years) congenital CMV infection (P = 0.11). Furthermore there was no association between long term growth or cognitive outcome and duration of viral excretion. However, a significantly greater proportion of children who excreted CMV for <4 years had SNHL and progressive SNHL compared with children with CMV excretion >4 years (P = 0.019, P = 0.009, respectively). Children congenitally infected with CMV are chronically infected for years, but the duration of CMV urinary excretion is not associated with abnormalities of growth, or neurodevelopmental deficits. However, SNHL and progressive SNHL were associated with a shorter duration of CMV excretion.

HPLC method for urinary theobromine determination: Effect of consumption of cocoa products on theobromine urinary excretion in children.

PubMed

Rodriguez, Adrian; Costa-Bauza, Antonia; Saez-Torres, Concepcion; Rodrigo, Dolores; Grases, Felix

2015-11-01

To validate a simple method of urinary theobromine determination, to assess urinary theobromine levels in 80 healthy children and to relate these levels to consumption of cocoa products. Urine samples were diluted, directly injected into an HPLC system, separated by gradient elution on a C18 column, and detected by UV spectrometry. The method was validated for linearity, limits of detection and quantification, imprecision, accuracy, recovery and interferences. The proposed method was used to assess 12-h day and 12-h night urinary theobromine excretion by 80 healthy children, divided into four groups based on consumption of cocoa products. In addition, urinary excretion of magnesium and oxalate, also present in cocoa, was measured in these four groups. The method was linear to a theobromine concentration of 278μmol/L (50mg/L). LOD and LOQ for urine samples, diluted 1:5 (vol/vol) with water, were 1.1 and 3.6μmol/L respectively. Within-run and between-run imprecisions (CV) were each <2%. Average recovery was 99%, and analysis of a certified reference sample showed an error <2.5%. Theobromine excretion levels were significantly higher in healthy children with higher consumption of cocoa products (p<0.001), but oxalate (p=0.098) and magnesium (p=0.068) excretion levels did not differ significantly. This validated method resulted in urinary theobromine determination with 100% recovery, without sample pretreatment. Urinary theobromine levels in healthy children were directly related to their consumption of cocoa products. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Associations of Urinary Caffeine and Caffeine Metabolites With Arterial Stiffness in a Large Population-Based Study.

PubMed

Ponte, Belen; Pruijm, Menno; Ackermann, Daniel; Ehret, Georg; Ansermot, Nicolas; Staessen, Jan A; Vogt, Bruno; Pechère-Bertschi, Antoinette; Burnier, Michel; Martin, Pierre-Yves; Eap, Chin B; Bochud, Murielle; Guessous, Idris

2018-05-01

To assess the influence of caffeine on arterial stiffness by exploring the association of urinary excretion of caffeine and its related metabolites with pulse pressure (PP) and pulse wave velocity (PWV). Families were randomly selected from the general population of 3 Swiss cities from November 25, 2009, through April 4, 2013. Pulse pressure was defined as the difference between the systolic and diastolic blood pressures obtained by 24-hour ambulatory monitoring. Carotid-femoral PWV was determined by applanation tonometry. Urinary caffeine, paraxanthine, theophylline, and theobromine excretions were measured in 24-hour urine collections. Multivariate linear and logistic mixed models were used to explore the associations of quartiles of urinary caffeine and metabolite excretions with PP, high PP, and PWV. We included 863 participants with a mean ± SD age of 47.1±17.6 years, 24-hour PP of 41.9±9.2 mm Hg, and PWV of 8.0±2.3 m/s. Mean (SE) brachial PP decreased from 43.5 (0.5) to 40.5 (0.6) mm Hg from the lowest to the highest quartiles of 24-hour urinary caffeine excretion (P<.001). The odds ratio (95% CI) of high PP decreased linearly from 1.0 to 0.52 (0.31-0.89), 0.38 (0.22-0.65), and 0.31 (0.18-0.55) from the lowest to the highest quartile of 24-hour urinary caffeine excretion (P<.001). Mean (SE) PWV in the highest caffeine excretion quartile was significantly lower than in the lowest quartile (7.8 [0.1] vs 8.1 [0.1] m/s; P=.03). Similar associations were found for paraxanthine and theophylline, whereas no associations were found with theobromine. Urinary caffeine, paraxanthine, and theophylline excretions were associated with decreased parameters of arterial stiffness, suggesting a protective effect of caffeine intake beyond its blood pressure-lowering effect. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

New anthropometry-based age- and sex-specific reference values for urinary 24-hour creatinine excretion based on the adult Swiss population.

PubMed

Forni Ogna, Valentina; Ogna, Adam; Vuistiner, Philippe; Pruijm, Menno; Ponte, Belen; Ackermann, Daniel; Gabutti, Luca; Vakilzadeh, Nima; Mohaupt, Markus; Martin, Pierre-Yves; Guessous, Idris; Péchère-Bertschi, Antoinette; Paccaud, Fred; Bochud, Murielle; Burnier, Michel

2015-02-27

Urinary creatinine excretion is used as a marker of completeness of timed urine collections, which are a keystone of several metabolic evaluations in clinical investigations and epidemiological surveys. We used data from two independent Swiss cross-sectional population-based studies with standardised 24-hour urinary collection and measured anthropometric variables. Only data from adults of European descent, with estimated glomerular filtration rate (eGFR) ≥60 ml/min/1.73 m2 and reported completeness of the urinary collection were retained. A linear regression model was developed to predict centiles of the 24-hour urinary creatinine excretion in 1,137 participants from the Swiss Survey on Salt and validated in 994 participants from the Swiss Kidney Project on Genes in Hypertension. The mean urinary creatinine excretion was 193 ± 41 μmol/kg/24 hours in men and 151 ± 38 μmol/kg/24 hours in women in the Swiss Survey on Salt. The values were inversely correlated with age and body mass index (BMI). We propose a validated prediction equation for 24-hour urinary creatinine excretion in the general European population, based on readily available variables such as age, sex and BMI, and a few derived normograms to ease its clinical application. This should help healthcare providers to interpret the completeness of a 24-hour urine collection in daily clinical practice and in epidemiological population studies.

Intercalated cell-specific Rh B glycoprotein deletion diminishes renal ammonia excretion response to hypokalemia

PubMed Central

Bishop, Jesse M.; Lee, Hyun-Wook; Handlogten, Mary E.; Han, Ki-Hwan; Verlander, Jill W.

2013-01-01

The ammonia transporter family member, Rh B Glycoprotein (Rhbg), is an ammonia-specific transporter heavily expressed in the kidney and is necessary for the normal increase in ammonia excretion in response to metabolic acidosis. Hypokalemia is a common clinical condition in which there is increased renal ammonia excretion despite the absence of metabolic acidosis. The purpose of this study was to examine Rhbg's role in this response through the use of mice with intercalated cell-specific Rhbg deletion (IC-Rhbg-KO). Hypokalemia induced by feeding a K+-free diet increased urinary ammonia excretion significantly. In mice with intact Rhbg expression, hypokalemia increased Rhbg protein expression in intercalated cells in the cortical collecting duct (CCD) and in the outer medullary collecting duct (OMCD). Deletion of Rhbg from intercalated cells inhibited hypokalemia-induced changes in urinary total ammonia excretion significantly and completely prevented hypokalemia-induced increases in urinary ammonia concentration, but did not alter urinary pH. We conclude that hypokalemia increases Rhbg expression in intercalated cells in the cortex and outer medulla and that intercalated cell Rhbg expression is necessary for the normal increase in renal ammonia excretion in response to hypokalemia. PMID:23220726

Urinary excretion ratio of xanthurenic acid/kynurenic acid as a functional biomarker of niacin nutritional status.

PubMed

Shibata, Katsumi; Yamazaki, Marika; Matsuyama, Yukiyo

2016-07-18

The present study was conducted to survey functional biomarkers for evaluation of niacin nutritional status. Over 500 enzymes require niacin as a coenzyme. Of these, we chose the tryptophan degradation pathway. To create niacin-deficient animals, quinolinic acid phosphoribosyltransferase-knock out mice were used in the present study because wild type mice can synthesize nicotinamide from tryptophan. When the mice were made niacin-deficient, the urinary excretion of xanthurenic acid (XA) was extremely low compared with control mice; however, it increased according to the recovery of niacin nutritional status. The urinary excretion of kynurenic acid (KA) was the reverse of XA. Kynurenine 3-monooxygenase, which needs NADPH, was thought to be suppressed by niacin deficiency. Thus, we calculated the urinary excretion ratio of XA:KA as a functional biomarker of niacin nutrition. The ratio increased according to recovering niacin nutritional status. Low values equate with low niacin nutritional status.

Effect of vitamin A supplementation on the urinary retinol excretion in very low birth weight infants.

PubMed

Schmiedchen, Bettina; Longardt, Ann Carolin; Loui, Andrea; Bührer, Christoph; Raila, Jens; Schweigert, Florian J

2016-03-01

Despite high-dose vitamin A supplementation of very low birth weight infants (VLBW, <1500 g), their vitamin A status does not improve substantially. Unknown is the impact of urinary retinol excretion on the serum retinol concentration in these infants. Therefore, the effect of high-dose vitamin A supplementation on the urinary vitamin A excretion in VLBW infants was investigated. Sixty-three VLBW infants were treated with vitamin A (5000 IU intramuscular, 3 times/week for 4 weeks); 38 untreated infants were classified as control group. On days 3 and 28 of life, retinol, retinol-binding protein 4 (RBP4), glomerular filtration rate, proteinuria, and Tamm-Horsfall protein were quantified in urine. On day 3 of life, substantial retinol and RBP4 losses were found in both groups, which significantly decreased until day 28. Notwithstanding, the retinol excretion was higher (P < 0.01) under vitamin A supplementation as compared to infants of the control group. On day 28 of life, the urinary retinol concentrations were predictive for serum retinol concentrations in the vitamin A treated (P < 0.01), but not in the control group (P = 0.570). High urinary retinol excretion may limit the vitamin A supplementation efficacy in VLBW infants. Advanced age and thus postnatal kidney maturation seems to be an important contributor in the prevention of urinary retinol losses.

Urinary D-lactate excretion in infants receiving Lactobacillus johnsonii with formula.

PubMed

Haschke-Becher, Elisabeth; Brunser, Oscar; Cruchet, Sylvia; Gotteland, Martin; Haschke, Ferdinand; Bachmann, Claude

2008-01-01

Supplementation with certain probiotics can improve gut microbial flora and immune function but should not have adverse effects. This study aimed to assess the risk of D-lactate accumulation and subsequent metabolic acidosis in infants fed on formula containing Lactobacillus johnsonii (La1). In the framework of a double-blind, randomized controlled trial enrolling 71 infants aged 4-5 months, morning urine samples were collected before and 4 weeks after being fed formulas with or without La1 (1 x 10(8)/g powder) or being breastfed. Urinary D- and L-lactate concentrations were assayed by enzymatic, fluorimetric methods and excretion was normalized per mol creatinine. At baseline, no significant differences in urinary D-/L-lactate excretion among the formula-fed and breastfed groups were found. After 4 weeks, D-lactate excretion did not differ between the two formula groups, but was higher in both formula groups than in breastfed infants. In all infants receiving La1, urinary D-lactate concentrations remained within the concentration ranges of age-matched healthy infants which had been determined in an earlier study using the same analytical method. Urinary L-lactate also did not vary over time or among groups. Supplementation of La1 to formula did not affect urinary lactate excretion and there is no evidence of an increased risk of lactic acidosis. Copyright 2008 S. Karger AG, Basel.

Mineral and nitrogen balance study - Results of metabolic observations on Skylab II 28-day orbital mission

NASA Technical Reports Server (NTRS)

Whedon, G. D.; Lutwak, L.; Reid, J.; Rambaut, P.; Whittle, M.; Smith, M.; Leach, C.

1975-01-01

The prediction that various stresses of flight, particularly weightlessness, would bring about significant derangements in the metabolism of the musculoskeletal system has been based on various balance-study observations of long-term immobilized or inactive bed rest. The three astronauts of Skylab II consumed a planned dietary intake of major metabolic elements in mixed foods and beverages and provided virtually complete collections of excreta for 31 days preflight, 28 days inflight, and 17 days postflight. Analyses showed that, in varying degree among the crewmen, urinary calcium increased gradually during flight in a pattern similar to that observed in bed-rest studies. Fecal calcium excretion did not change significantly, but calcium balance, owing to the urinary calcium rise, became either negative or less positive than in preflight measurement. Increased excretion and negative nitrogen and phosphorus balances inflight indicated appreciable loss of muscle tissue in all three crewmen. Significant losses also occurred inflight in potassium, sodium, and magnesium. Based on the similarity in pattern and degree between these observations of calcium, phosphorus, and nitrogen loss, musculoskeletal integrity would not be threatened in space flights of up to at least 3 months. However, if similar changes occur in the planed Skylab flights for considerably more than 28 days, concern for capable musculoskeletal function should be serious for flights of very many months' duration.

Effect of potato on acid-base and mineral homeostasis in rats fed a high-sodium chloride diet.

PubMed

Narcy, Agnès; Robert, Laetitia; Mazur, Andrzej; Demigné, Christian; Rémésy, Christian

2006-05-01

Excessive dietary NaCl in association with a paucity of plant foods, major sources of K alkaline salts, is a common feature in Western eating habits which may lead to acid-base disorders and to Ca and Mg wasting. In this context, to evaluate the effects of potato, rich in potassium citrate, on acid-base homeostasis and mineral retention, Wistar rats were fed wheat starch (WS) or cooked potato (CP) diets with a low (0.5 %) or a high (2 %) NaCl content during 3 weeks. The replacement of WS by CP in the diets resulted in a significant urinary alkalinisation (pH from 5.5 to 7.3) parallel to a rise in citrate and K excretion. Urinary Ca and Mg elimination represented respectively 17 and 62 % of the daily absorbed mineral in rats fed the high-salt WS diet compared with 5 and 28 % in rats fed the high-salt CP diet. The total SCFA concentration in the caecum was 3-fold higher in rats fed the CP diets compared with rats fed the WS diets, and it led to a significant rise in Ca and Mg intestinal absorption (Ca from 39 to 56 %; Mg from 37 to 60 %). The present model of low-grade metabolic acidosis indicates that CP may be effective in alkalinising urine, enhancing citrate excretion and ameliorating Ca and Mg balance.

Metabolism of boldenone in man: gas chromatographic/mass spectrometric identification of urinary excreted metabolites and determination of excretion rates.

PubMed

Schänzer, W; Donike, M

1992-01-01

Urinary metabolites of boldenone (androsta-1,4-dien-17 beta-ol-3-one) following oral administration of boldenone (doses from 11 to 80 mg) to man were isolated from urine via XAD-2 adsorption and enzymatic hydrolysis with beta-glucuronidase from Escherichia coli. The isolated metabolites were derivatized with N-methyl-N-trimethylsilyltri- fluoroacetamide/trimethyliodosilane and analysed by gas chromatography/mass spectrometry with electron impact (EI) ionization at 70 eV. Boldenone (I) and four metabolites were identified after hydrolysis of the urine with beta-glucuronidase: 5 beta-androst-1-en-17 beta-ol-3-one (II), 5 beta-androst-1-ene-3 alpha, 17 beta-diol (III), 5 beta-androst-1-en-3 alpha-ol-17-one (IV) and 5 beta-androst-1-en-6 beta-ol-3,17-dione (V). Five further metabolites in low concentration were identified without enzymatic hydrolysis after treatment of the urine with potassium carbonate: 5 beta-androst-1-ene-3,17-dione (VI), 5 alpha-androst-1-ene-3,17-dione (VII), androsta-1,4-diene-3,17-dione (VIII), androsta-1,4-diene-6 beta,17 beta-diol-3-one (IX) and androsta-1,4-dien-6 beta-ol-3,17-dione (X). The identification of the metabolites is based on the gas chromatography retention index, high-performance liquid chromatography retention, EI mass spectrum, chemical reactions of the isolated metabolites, and synthesis of metabolites II, III, IV, VI and VII. The EI mass spectra of the bis-trimethylsilyl derivatives of boldenone and its metabolites display all intense molecular ions, M-15 ions and fragment ions originating from cleavage of the B-ring. The excreted metabolites can be separated in basic extractable labile conjugates and in stable conjugates. More than 95% of metabolites are excreted as stable conjugates.

Diabetic ketoacidosis producing extreme hyperkalemia in a patient with type 1 diabetes on hemodialysis.

PubMed

Yamada, Hodaka; Funazaki, Shunsuke; Kakei, Masafumi; Hara, Kazuo; Ishikawa, San-E

2017-01-01

Diabetic ketoacidosis (DKA) is a critical complication of type 1 diabetes associated with water and electrolyte disorders. Here, we report a case of DKA with extreme hyperkalemia (9.0 mEq/L) in a patient with type 1 diabetes on hemodialysis. He had a left frontal cerebral infarction resulting in inability to manage his continuous subcutaneous insulin infusion pump. Electrocardiography showed typical changes of hyperkalemia, including absent P waves, prolonged QRS interval and tented T waves. There was no evidence of total body water deficit. After starting insulin and rapid hemodialysis, the serum potassium level was normalized. Although DKA may present with hypokalemia, rapid hemodialysis may be necessary to resolve severe hyperkalemia in a patient with renal failure. Patients with type 1 diabetes on hemodialysis may develop ketoacidosis because of discontinuation of insulin treatment.Patients on hemodialysis who develop ketoacidosis may have hyperkalemia because of anuria.Absolute insulin deficit alters potassium distribution between the intracellular and extracellular space, and anuria abolishes urinary excretion of potassium.Rapid hemodialysis along with intensive insulin therapy can improve hyperkalemia, while fluid infusions may worsen heart failure in patients with ketoacidosis who routinely require hemodialysis.

Clinical utility of patiromer, sodium zirconium cyclosilicate, and sodium polystyrene sulfonate for the treatment of hyperkalemia: an evidence-based review

PubMed Central

Beccari, Mario V; Meaney, Calvin J

2017-01-01

Introduction Hyperkalemia is a serious medical condition that often manifests in patients with chronic kidney disease and heart failure. Renin–angiotensin–aldosterone system inhibitors are known to improve outcomes in these disease states but can also cause drug-induced hyperkalemia. New therapeutic options exist for managing hyperkalemia in these patients which warrant evidence-based evaluation. Aim The objective of this article was to review the efficacy and safety evidence for patiromer, sodium zirconium cyclosilicate (ZS9), and sodium polystyrene sulfonate (SPS) for the treatment of hyperkalemia. Evidence review Current treatment options to enhance potassium excretion are SPS and loop diuretics, which are complicated by ambiguous efficacy and known toxicities. Patiromer and ZS9 are new agents designed to address this treatment gap. Both unabsorbable compounds bind potassium in the gastrointestinal (GI) tract to facilitate fecal excretion. The capacity to bind other medications in the GI tract infers high drug–drug interaction potential, which has been demonstrated with patiromer but not yet investigated with ZS9 or SPS. Phase II and III clinical trials of patiromer and ZS9 demonstrated clear evidence of a dose-dependent potassium-lowering effect and the ability to initiate, maintain, or titrate renin–angiotensin–aldosterone system inhibitors. There is limited evidence base for SPS: two small clinical trials indicated potassium reduction in chronic hyperkalemia. All agents may cause adverse GI effects, although they are less frequent with ZS9. Concerns remain for SPS to cause rare GI damage. Electrolyte abnormalities occurred with patiromer and SPS, whereas urinary tract infections, edema, and corrected QT-interval prolongations were reported with ZS9. Conclusion Patiromer and ZS9 have improved upon the age-old standard SPS for the treatment of hyperkalemia. Additional research should focus on drug–drug interactions in patients on multiple medications, incidence of rare adverse events, and use in high-risk populations. PMID:28356904

Comparison of synchronization of primate circadian rhythms by light and food

NASA Technical Reports Server (NTRS)

Sulzman, F. M.; Fuller, C. A.; Moore-Ede, M. C.

1978-01-01

It is a well-documented fact that cycles of light and dark (LD) are the major entraining agent or 'zeitgeber' for circadian rhythms and that cycles of eating and fasting (EF) are capable of synchronizing a few circadian rhythms in the squirrel monkey. In this paper, by contrasting how these rhythms are timed by LD and EF cycles, the differential coupling to the oscillating system within adult male squirrel monkeys is examined. The variables measured are the rhythms of drinking, colonic temperature, and urinary potassium and water excretion. Attention is given to a comparison of the reproducibility of the averaged waveforms of the rhythms, the stability of the timing of a phase reference point, and the rate of resynchronization of these rhythms following an abrupt 8-hr phase delay in the zeitgeber. It is shown that the colonic temperature rhythm is more tightly controlled by LD than EF cycles, and that the drinking and urinary rhythms are more tightly coupled to EF than LD cycles.

Diuretic effect of extracts, fractions and two compounds 2α,3β,19α-trihydroxy-urs-12-en-28-oic acid and 5-hydroxy-3,6,7,8,4'-pentamethoxyflavone from Rubus rosaefolius Sm. (Rosaceae) leaves in rats.

PubMed

de Souza, Priscila; Boeing, Thaise; Somensi, Lincon Bordignon; Cechinel-Zanchett, Camile Cecconi; Bastos, Jairo Kenupp; Petreanu, Marcel; Niero, Rivaldo; Cechinel-Filho, Valdir; da Silva, Luisa Mota; de Andrade, Sérgio Faloni

2017-04-01

Although diuretics have been widely used to treat hypertension along with others cardiovascular and renal disorders, no scientific data have been recorded to support the diuretic properties of Rubus rosaefolius Sm. (Rosaceae), a plant popularly used in Brazil to treat hypertension. Male Wistar rats were orally treated with: vehicle; hydrochlorothiazide; aqueous (AERR) and methanolic (MERR) extracts; dichloromethane (DCM), hexane (HEX) and ethyl acetate (EA) fractions; and the isolated compounds 2α,3β,19α-trihydroxy-urs-12-en-28-oic acid (TUA) and 5-hydroxy-3,6,7,8,4'-pentamethoxyflavone (PMF). At the end of the experiment (after 8 or 24 h), urine volume and other urine or plasma parameters were measured. AERR and MERR, at 100 and 30 mg/kg, respectively, induced diuretic, natriuretic and kaliuretic effect. Additionally, the DCM and HEX, but not EA, at 10 mg/kg, also increased urine volume and Na + and K + excretion. Both active constituents, TUA and PMF, at doses of 1 and 3 mg/kg, showed an augmented diuretic and natriuretic index. While TUA revealed a kaliuretic action, PMF did not interfere with potassium excretion. The compounds increased urinary creatinine, but not urea, levels. TUA was able to decrease calcium excretion, as well as HCTZ, while PMF effect was associated with increased urinary prostaglandin E 2 levels. The non-selective muscarinic receptor antagonist (atropine) prevented TUA-induced diuresis. In addition, indomethacin (a cyclooxygenase inhibitor) and atropine, exhibited the ability to block the diuretic effects prompted by PMF. Our study demonstrates the diuretic effect of extracts, fractions and two natural compounds obtained from R. rosaefolius leaves in rats.

Space motion sickness medications: interference with biomedical parameters

NASA Technical Reports Server (NTRS)

Vernikos-Danellis, J.; Winget, C. M.; Leach, C. S.; Rosenblatt, L. S.; Lyman, J.; Beljan, J. R.

1977-01-01

The possibility that drugs administered to Skylab 3 (SL-3) and 4 (SL-4) crewmen for space motion sickness may have interfered with their biomedical evaluation in space was investigated. Healthy volunteers received combinations of Scopolamine/Dexedrine for four days in regimens similar to those used in these missions. Urine samples, heart rate, body temperature, mood and performance were analyzed for drug-related changes. Twenty-four hour urine samples were analyzed by the same procedures as those used to analyze the flight samples. Hormone concentrations determined included cortisol, epinephrine, norepinephrine, aldosterone and antidiuretic hormone (ADH). In addition, volume, specific gravity, osmolarity, sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), chloride (Cl), inorganic phosphate, uric acid and creatinine were measured. Performance was not affected by the Scopolamine/Dexedrine. The drug combination increased daily mean heart rate (HR) significantly in all the subjects and daily mean rectal temperature (RT) in some of the subjects. A 2-4 hr phase shift in the HR circadian rhythm was also observed which indicates that internal circadian synchrony was disturbed by the drugs. Psychological and subjective evaluation indicated that the subjects could usually identify which days they were given the drugs by an increase in tension and anxiety, decreased patience, restlessness, decreased appetite, difficulty in sleeping and feelings of increased heart rate and body temperature. Urinary electrolytes were not changed significantly by the drug, but marked and significant changes occurred in urine volume and hormone excretion patterns. Scopolamine/Dexedrine caused consistent elevations in urinary cortisol and epinephrine and a transient elevation in ADH. Norepinephrine excretion was decreased, but there was no significant change in aldosterone excretion or in 24 hr urine volume. A comparison of these findings with the first four days of inflight data from the SL-3 and SL-4 missions leads to the conclusion that the dramatic increases in aldosterone excretion during the first three days of spaceflight probably can be directly attributed to weightlessness, whereas the antimotion sickness medication could have substantially contributed to the early increased excretion of epinephrine and cortisol during these missions.

Role of 11beta-hydroxysteroid dehydrogenase 2 renal activity in potassium homeostasis in rats with chronic renal failure.

PubMed

Yeyati, N L; Altuna, M E; Damasco, M C; Mac Laughlin, M A

2010-01-01

Aldosterone concentrations vary in advanced chronic renal failure (CRF). The isozyme 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2), which confers aldosterone specificity for mineralocorticoid receptors in distal tubules and collecting ducts, has been reported to be decreased or normal in patients with renal diseases. Our objective was to determine the role of aldosterone and 11beta-HSD2 renal microsome activity, normalized for glomerular filtration rate (GFR), in maintaining K+ homeostasis in 5/6 nephrectomized rats. Male Wistar rats weighing 180-220 g at the beginning of the study were used. Rats with experimental CRF obtained by 5/6 nephrectomy (N = 9) and sham rats (N = 10) were maintained for 4 months. Systolic blood pressure and plasma creatinine (Pcr) concentration were measured at the end of the experiment. Sodium and potassium excretion and GFR were evaluated before and after spironolactone administration (10 mg.kg-1.day-1 for 7 days) and 11beta-HSD2 activity on renal microsomes was determined. Systolic blood pressure (means +/- SEM; Sham = 105 +/- 8 and CRF = 149 +/- 10 mmHg) and Pcr (Sham = 0.42 +/- 0.03 and CRF = 2.53 +/- 0.26 mg/dL) were higher (P < 0.05) while GFR (Sham = 1.46 +/- 0.26 and CRF = 0.61 +/- 0.06 mL/min) was lower (P < 0.05) in CRF, and plasma aldosterone (Pald) was the same in the two groups. Urinary sodium and potassium excretion was similar in the two groups under basal conditions but, after spironolactone treatment, only potassium excretion was decreased in CRF rats (sham = 0.95 +/- 0.090 (before) vs 0.89 +/- 0.09 microEq/min (after) and CRF = 1.05 +/- 0.05 (before) vs 0.37 +/- 0.07 microEq/min (after); P < 0.05). 11beta-HSD2 activity on renal microsomes was lower in CRF rats (sham = 0.807 +/- 0.09 and CRF = 0.217 +/- 0.07 nmol.min-1.mg protein-1; P < 0.05), although when normalized for mL GFR it was similar in both groups. We conclude that K+ homeostasis is maintained during CRF development despite normal Pald levels. This adaptation may be mediated by renal 11beta-HSD2 activity, which, when normalized for GFR, became similar to that of control rats, suggesting that mineralocorticoid receptors maintain their aldosterone selectivity.

Assessment of urinary betaine as a marker of diabetes mellitus in cardiovascular patients.

PubMed

Schartum-Hansen, Hall; Ueland, Per M; Pedersen, Eva R; Meyer, Klaus; Ebbing, Marta; Bleie, Øyvind; Svingen, Gard F T; Seifert, Reinhard; Vikse, Bjørn E; Nygård, Ottar

2013-01-01

Abnormal urinary excretion of betaine has been demonstrated in patients with diabetes or metabolic syndrome. We aimed to identify the main predictors of excretion in cardiovascular patients and to make initial assessment of its feasibility as a risk marker of future diabetes development. We used data from 2396 patients participating in the Western Norway B-vitamin Intervention Trial, who delivered urine and blood samples at baseline, and in the majority at two visits during follow-up of median 39 months. Betaine in urine and plasma were measured by liquid-chromatography-tandem mass spectrometry. The strongest determinants of urinary betaine excretion by multiple regression were diabetes mellitus, age and estimated glomerular filtration rate; all p<0.001. Patients with diabetes mellitus (n = 264) had a median excretion more than three times higher than those without. We found a distinct non-linear association between urinary betaine excretion and glycated hemoglobin, with a break-point at 6.5%, and glycated hemoglobin was the strongest determinant of betaine excretion in patients with diabetes mellitus. The discriminatory power for diabetes mellitus corresponded to an area under the curve by receiver-operating characteristics of 0.82, and betaine excretion had a coefficient of reliability of 0.73. We also found a significant, independent log-linear relation between baseline betaine excretion and the risk of developing new diabetes during follow-up. The good discriminatory power for diabetes, high test-retest stability and independent association with future risk of new diabetes should motivate further investigation on the role of betaine excretion in risk assessment and long-term follow-up of diabetes mellitus.

Applying recovery biomarkers to calibrate self-report measures of sodium and potassium in the Hispanic Community Health Study/Study of Latinos

PubMed Central

Mossavar-Rahmani, Yasmin; Sotres-Alvarez, Daniela; Wong, William W.; Loria, Catherine M.; Gellman, Marc D.; Van Horn, Linda; Alderman, Michael H.; Beasley, Jeannette M.; Lora, Claudia M.; Siega-Riz, Anna Maria; Kaplan, Robert C.; Shaw, Pamela A.

2017-01-01

Measurement error in assessment of sodium and potassium intake obscures associations with health outcomes. The level of this error in a diverse US Hispanic/Latino population is unknown. We investigated measurement error in self-reported dietary intake of sodium and potassium and examined differences by background (Central American, Cuban, Dominican, Mexican, Puerto Rican and South American). In 2010-2012, we studied 447 participants aged 18-74 years from four communities (Miami, Bronx, Chicago, and San Diego), obtaining objective 24-hour urinary sodium and potassium excretion measures. Self-report was captured from two interviewer-administered 24-hour dietary recalls. Twenty percent of the sample repeated the study. We examined bias in self-reported sodium and potassium from diet and the association of mismeasurement with participant characteristics. Linear regression relating self-report with objective measures was used to develop calibrations equations. Self-report underestimated sodium intake by 19.8% and 20.8% and potassium intake by 1.3% and 4.6% in men and women, respectively. Sodium intake underestimation varied by Hispanic/Latino background (p<0.05) and was associated with higher body mass index. Potassium intake underestimation was associated with higher BMI, lower restaurant score (indicating lower consumption of foods prepared away from home and/or eaten outside the home), and supplement use. The R2 was 19.7% and 25.0% for the sodium and potassium calibration models, respectively, increasing to 59.5% and 61.7% after adjusting for within-person variability in each biomarker. These calibration equations, corrected for subject-specific reporting error, have the potential to reduce bias in diet-disease associations within this largest cohort of Hispanics in the US. PMID:28205551

Desmopressin resistant nocturnal polyuria secondary to increased nocturnal osmotic excretion.

PubMed

Dehoorne, Jo L; Raes, Ann M; van Laecke, Erik; Hoebeke, Piet; Vande Walle, Johan G

2006-08-01

We investigated the role of increased solute excretion in children with desmopressin resistant nocturnal enuresis and nocturnal polyuria. A total of 42 children with monosymptomatic nocturnal enuresis and significant nocturnal polyuria with high nocturnal urinary osmolality (more than 850 mmol/l) were not responding to desmopressin. A 24-hour urinary concentration profile was obtained with measurement of urine volume, osmolality, osmotic excretion and creatinine. The control group consisted of 100 children without enuresis. Based on osmotic excretion patients were classified into 3 groups. Group 1 had 24-hour increased osmotic excretion, most likely secondary to a high renal osmotic load. This was probably diet related since 11 of these 12 patients were obese. Group 2 had increased osmotic excretion in the evening and night, probably due to a high renal osmotic load caused by the diet characteristics of the evening meal. Group 3 had deficient osmotic excretion during the day, secondary to extremely low fluid intake to compensate for small bladder capacity. Nocturnal polyuria with high urinary osmolality in our patients with desmopressin resistant monosymptomatic nocturnal enuresis is related to abnormal increased osmotic excretion. This may be explained by their fluid and diet habits, eg daytime fluid restriction, and high protein and salt intake.

Urinary potassium is a potential biomarker of disease activity in Ulcerative colitis and displays in vitro immunotolerant role.

PubMed

Goyal, Sandeep; Rampal, Ritika; Kedia, Saurabh; Mahajan, Sandeep; Bopanna, Sawan; Yadav, Devesh P; Jain, Saransh; Singh, Amit Kumar; Wari, Md Nahidul; Makharia, Govind; Awasthi, Amit; Ahuja, Vineet

2017-12-22

We evaluated the in-vitro effect of potassium on CD4 + T cells and the role of urinary potassium as a potential biomarker of disease activity in patients with ulcerative colitis (UC). This prospective observational cohort study included healthy controls (n = 18) and UC patients [n = 30, median age: 40 (IQR: 28-46) years, 17 males)] with active disease(assessed by Mayo score) from September 2015-May 2016. Twenty-four hours urinary potassium along with fecal calprotectin (FCP) were estimated in UC patients (at baseline and follow-up after 3-6 months) and controls. In healthy volunteers, we also assessed the effect of potassium on CD4 + T cells differentiated in the presence of Th17 polarizing condition. UC patients had significantly higher FCP (368.2 ± 443.04 vs 12.44 ± 27.51, p < 0.001) and significantly lower urinary potassium (26.6 ± 16.9 vs 46.89 ± 35.91, p = 0.01) levels than controls. At follow-up, a significant increase in urinary potassium among patients who had clinical response [n = 22, 21.4 (14.4-39.7) to 36.5 (20.5-61.6), p = 0.04] and remission [n = 12, 18.7 (9.1-34.3) to 36.5 (23.4-70.5), p = 0.05] was accompanied with a parallel decline in FCP. On in-vitro analysis, potassium under Th17 polarizing conditions significantly inhibited IL-17 and interferon-[Formula: see text] expression while favoring the induction of FoxP3 + T cells. Therefore, urinary potassium levels are inversely associated with disease activity in UC with in-vitro data supporting an immune-tolerant role of potassium.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kramer, L.

The effect of drugs such as glucocorticoids and thyroid extract on calcium metabolism is unknown. However, several other medications affect the excretion and intestinal absorption of calcium. A controlled study was carried out to investigate these aspects. Urinary calcium was determined for 3 months during the long-term intake of the antituberculous drug isoniazid (INH) and of the antibiotic tetracycline. The effect of the diuretics furosemide and hydrochlorothiazide, of several aluminum-containing antacids, of thyroid extract and of corticosteroids was also studied. Metabolic balances of calcium, phosphorus, magnesium and zinc were determined, as well as the intestinal absorption of calcium using Camore » 47. Plasma levels, urinary and fecal excretions of Ca 47 were determined. All drugs tested increased urinary calcium except for the diuretic hydrochlorothiazide. Regarding the effect of corticosteroids: the intestinal absorption of calcium was unchanged after the short-term use and was very high after long-term use. The studies have shown that several commonly used drugs induce an increase in urinary calcium excretion which may contribute to calcium loss, if this increase persists for prolonged periods of time. Urinary excretions of phosphorus, magnesium and zinc increased in some of the studies.« less

Randomized controlled trial of febuxostat versus allopurinol or placebo in individuals with higher urinary uric acid excretion and calcium stones.

PubMed

Goldfarb, David S; MacDonald, Patricia A; Gunawardhana, Lhanoo; Chefo, Solomon; McLean, Lachy

2013-11-01

Higher urinary uric acid excretion is a suspected risk factor for calcium oxalate stone formation. Febuxostat, a xanthine oxidoreductase inhibitor, is effective in lowering serum urate concentration and urinary uric acid excretion in healthy volunteers and people with gout. This work studied whether febuxostat, compared with allopurinol and placebo, would reduce 24-hour urinary uric acid excretion and prevent stone growth or new stone formation. In this 6-month, double-blind, multicenter, randomized controlled trial, hyperuricosuric participants with a recent history of calcium stones and one or more radio-opaque calcium stone ≥ 3 mm (as seen by multidetector computed tomography) received daily febuxostat at 80 mg, allopurinol at 300 mg, or placebo. The primary end point was percent change from baseline to month 6 in 24-hour urinary uric acid. Secondary end points included percent change from baseline to month 6 in size of index stone and change from baseline in the mean number of stones and 24-hour creatinine clearance. Of 99 enrolled participants, 86 participants completed the study. Febuxostat led to significantly greater reduction in 24-hour urinary uric acid (-58.6%) than either allopurinol (-36.4%; P=0.003) or placebo (-12.7%; P<0.001). Percent change from baseline in the size of the largest calcium stone was not different with febuxostat compared with allopurinol or placebo. There was no change in stone size, stone number, or renal function. No new safety concerns were noted for either drug. Febuxostat (80 mg) lowered 24-hour urinary uric acid significantly more than allopurinol (300 mg) in stone formers with higher urinary uric acid excretion after 6 months of treatment. There was no change in stone size or number over the 6-month period.

Formic acid excretion in rats exposed to trichloroethylene: a possible explanation for renal toxicity in long-term studies.

PubMed

Green, T; Dow, J; Foster, J R; Hext, P M

1998-05-15

Rats exposed to trichloroethylene, either by gavage or by inhalation, excreted large amounts of formic acid in urine which was accompanied by a change in urinary pH, increased excretion of ammonia, and slight increases in the excretion of calcium. Following a single 6-h exposure to 500 ppm trichloroethylene, the excretion of formic acid was comparable to that seen after a 500 mg/kg dose of formic acid itself, yet the half-life was markedly different. Formate excretion in trichloroethylene treated rats reached a maximum on day 2 and had a half-life of 4-5 days, whereas urinary excretion was complete within 24 h following a single dose of formic acid itself. Formic acid was shown not to be a metabolite of trichloroethylene. When rats were exposed to 250 or 500 ppm trichloroethylene, 6 h/day, for 28 days, the only significant effects were increased formic acid and ammonia excretion, and a change in urinary pH. There was no evidence of morphological liver or kidney damage. Long-term exposure to formic acid is known to cause kidney damage suggesting that excretion of this acid may contribute to the kidney damage seen in the long-term studies with trichloroethylene.

Kidney injury biomarkers and urinary creatinine variability in nominally healthy adults

EPA Science Inventory

Environmental exposure diagnostics use creatinine concentrations in urine aliquots as the internal standard for dilution normalization of all other excreted metabolites when urinary excretion rate data are not available. This is a reasonable approach for healthy adults as creati...

Effect of sauna bathing and beer ingestion on plasma concentrations of purine bases.

PubMed

Yamamoto, Tetsuya; Moriwaki, Yuji; Ka, Tuneyoshi; Takahashi, Sumio; Tsutsumi, Zenta; Cheng, Jidong; Inokuchi, Taku; Yamamoto, Asako; Hada, Toshikazu

2004-06-01

To determine whether sauna bathing alone or in combination with beer ingestion increases the plasma concentration of uric acid, 5 healthy subjects were tested. Urine and plasma measurements were performed before and after each took a sauna bath, ingested beer, and ingested beer just after taking a sauna bath, with a 2-week interval between each activity. Sauna bathing alone increased the plasma concentrations of uric acid and oxypurines (hypoxanthine and xanthine), and decreased the urinary and fractional excretion of uric acid, while beer ingestion alone increased the plasma concentrations and urinary excretion of uric acid and oxypurines. A combination of both increased the plasma concentration of uric acid and oxypurines, and decreased the urinary and fractional excretion of uric acid, with an increase in the urinary excretion of oxypurines. The increase in plasma concentration of uric acid with the combination protocol was not synergistic as compared to the sum of the increases by each alone. Body weight, urine volume, and the urinary excretion of sodium and chloride via dehydration were decreased following sauna bathing alone. These results suggest that sauna bathing had a relationship with enhanced purine degradation and a decrease in the urinary excretion of uric acid, leading to an increase in the plasma concentration of uric acid. Further, we concluded that extracellular volume loss may affect the common renal transport pathway of uric acid and xanthine. Therefore, it is recommended that patients with gout refrain from drinking alcoholic beverages, including beer, after taking a sauna bath, since the increase in plasma concentration of uric acid following the combination of sauna bathing and beer ingestion was additive.

High Dietary Sodium Intake Assessed by Estimated 24-h Urinary Sodium Excretion Is Associated with NAFLD and Hepatic Fibrosis

PubMed Central

Huh, Ji Hye; Lee, Kyong Joo; Lim, Jung Soo; Lee, Mi Young; Park, Hong Jun; Kim, Moon Young; Kim, Jae Woo; Chung, Choon Hee; Shin, Jang Yel; Kim, Hyun-Soo; Kwon, Sang Ok; Baik, Soon Koo

2015-01-01

Background Although high sodium intake is associated with obesity and hypertension, few studies have investigated the relationship between sodium intake and non-alcoholic fatty liver disease (NAFLD). We evaluated the association between sodium intake assessed by estimated 24-h urinary sodium excretion and NAFLD in healthy Koreans. Methods We analyzed data from 27,433 participants in the Korea National Health and Nutrition Examination Surveys (2008–2010). The total amount of sodium excretion in 24-h urine was estimated using Tanaka’s equations from spot urine specimens. Subjects were defined as having NAFLD when they had high scores in previously validated NAFLD prediction models such as the hepatic steatosis index (HSI) and fatty liver index (FLI). BARD scores and FIB-4 were used to define advanced fibrosis in subjects with NAFLD. Results The participants were classified into three groups according to estimated 24-h urinary excretion tertiles. The prevalence of NAFLD as assessed by both FLI and HSI was significantly higher in the highest estimated 24-h urinary sodium excretion tertile group. Even after adjustment for confounding factors including body fat and hypertension, the association between higher estimated 24-h urinary sodium excretion and NAFLD remained significant (Odds ratios (OR) 1.39, 95% confidence interval (CI) 1.26–1.55, in HSI; OR 1.75, CI 1.39–2.20, in FLI, both P < 0.001). Further, subjects with hepatic fibrosis as assessed by BARD score and FIB-4 in NAFLD patients had higher estimated 24-h urinary sodium values. Conclusions High sodium intake was independently associated with an increased risk of NAFLD and advanced liver fibrosis. PMID:26571018

High Dietary Sodium Intake Assessed by Estimated 24-h Urinary Sodium Excretion Is Associated with NAFLD and Hepatic Fibrosis.

PubMed

Huh, Ji Hye; Lee, Kyong Joo; Lim, Jung Soo; Lee, Mi Young; Park, Hong Jun; Kim, Moon Young; Kim, Jae Woo; Chung, Choon Hee; Shin, Jang Yel; Kim, Hyun-Soo; Kwon, Sang Ok; Baik, Soon Koo

2015-01-01

Although high sodium intake is associated with obesity and hypertension, few studies have investigated the relationship between sodium intake and non-alcoholic fatty liver disease (NAFLD). We evaluated the association between sodium intake assessed by estimated 24-h urinary sodium excretion and NAFLD in healthy Koreans. We analyzed data from 27,433 participants in the Korea National Health and Nutrition Examination Surveys (2008-2010). The total amount of sodium excretion in 24-h urine was estimated using Tanaka's equations from spot urine specimens. Subjects were defined as having NAFLD when they had high scores in previously validated NAFLD prediction models such as the hepatic steatosis index (HSI) and fatty liver index (FLI). BARD scores and FIB-4 were used to define advanced fibrosis in subjects with NAFLD. The participants were classified into three groups according to estimated 24-h urinary excretion tertiles. The prevalence of NAFLD as assessed by both FLI and HSI was significantly higher in the highest estimated 24-h urinary sodium excretion tertile group. Even after adjustment for confounding factors including body fat and hypertension, the association between higher estimated 24-h urinary sodium excretion and NAFLD remained significant (Odds ratios (OR) 1.39, 95% confidence interval (CI) 1.26-1.55, in HSI; OR 1.75, CI 1.39-2.20, in FLI, both P < 0.001). Further, subjects with hepatic fibrosis as assessed by BARD score and FIB-4 in NAFLD patients had higher estimated 24-h urinary sodium values. High sodium intake was independently associated with an increased risk of NAFLD and advanced liver fibrosis.

Polyethylene glycol versus dual sugar assay for gastrointestinal permeability analysis: is it time to choose?

PubMed

van Wijck, Kim; Bessems, Babs Afm; van Eijk, Hans Mh; Buurman, Wim A; Dejong, Cornelis Hc; Lenaerts, Kaatje

2012-01-01

Increased intestinal permeability is an important measure of disease activity and prognosis. Currently, many permeability tests are available and no consensus has been reached as to which test is most suitable. The aim of this study was to compare urinary probe excretion and accuracy of a polyethylene glycol (PEG) assay and dual sugar assay in a double-blinded crossover study to evaluate probe excretion and the accuracy of both tests. Gastrointestinal permeability was measured in nine volunteers using PEG 400, PEG 1500, and PEG 3350 or lactulose-rhamnose. On 4 separate days, permeability was analyzed after oral intake of placebo or indomethacin, a drug known to increase intestinal permeability. Plasma intestinal fatty acid binding protein and calprotectin levels were determined to verify compromised intestinal integrity after indomethacin consumption. Urinary samples were collected at baseline, hourly up to 5 hours after probe intake, and between 5 and 24 hours. Urinary excretion of PEG and sugars was determined using high-pressure liquid chromatography-evaporative light scattering detection and liquid chromatography-mass spectrometry, respectively. Intake of indomethacin increased plasma intestinal fatty acid-binding protein and calprotectin levels, reflecting loss of intestinal integrity and inflammation. In this state of indomethacin-induced gastrointestinal compromise, urinary excretion of the three PEG probes and lactulose increased compared with placebo. Urinary PEG 400 excretion, the PEG 3350/PEG 400 ratio, and the lactulose/rhamnose ratio could accurately detect indomethacin-induced increases in gastrointestinal permeability, especially within 2 hours of probe intake. Hourly urinary excretion and diagnostic accuracy of PEG and sugar probes show high concordance for detection of indomethacin-induced increases in gastrointestinal permeability. This comparative study improves our knowledge of permeability analysis in man by providing a clear overview of both tests and demonstrates equivalent performance in the current setting.

Anemia, Iron Deficiency and Iodine Deficiency among Nepalese School Children.

PubMed

Khatiwada, Saroj; Lamsal, Madhab; Gelal, Basanta; Gautam, Sharad; Nepal, Ashwini Kumar; Brodie, David; Baral, Nirmal

2016-07-01

To assess iodine and iron nutritional status among Nepalese school children. A cross-sectional, community based study was conducted in the two districts, Ilam (hilly region) and Udayapur (plain region) of eastern Nepal. A total of 759 school children aged 6-13 y from different schools within the study areas were randomly enrolled. A total of 759 urine samples and 316 blood samples were collected. Blood hemoglobin level, serum iron, total iron binding capacity and urinary iodine concentration was measured. Percentage of transferrin saturation was calculated using serum iron and total iron binding capacity values. The mean level of hemoglobin, serum iron, total iron binding capacity, transferrin saturation and median urinary iodine excretion were 12.29 ± 1.85 g/dl, 70.45 ± 34.46 μg/dl, 386.48 ± 62.48 μg/dl, 19.94 ± 12.07 % and 274.67 μg/L respectively. Anemia, iron deficiency and iodine deficiency (urinary iodine excretion <100 μg/L) were present in 34.5 %, 43.4 % and 12.6 % children respectively. Insufficient urinary iodine excretion (urinary iodine excretion <100 μg/L) was common in anemic and iron deficient children. Iron deficiency and anemia are common in Nepalese children, whereas, iodine nutrition is more than adequate. Low urinary iodine excretion was common in iron deficiency and anemia.

Lowering urinary oxalate excretion to decrease calcium oxalate stone disease

PubMed Central

Knight, John; Assimos, Dean G.

2016-01-01

Dietary modifications should be considered as a first line approach in the treatment of idiopathic calcium oxalate nephrolithiasis. The amounts of oxalate and calcium consumed in the diet are significant factors in the development of the disease due to their impact on urinary oxalate excretion. There are a number of strategies that can be employed to reduce oxalate excretion. The consumption of oxalate-rich foods should be avoided and calcium intake adjusted to 1000–1200 mg/day. To encourage compliance it should be emphasized to patients that they be vigilant with this diet as a deviation in any meal or snack could potentially result in significant stone growth. The evidence underlying these two modifications is outlined and other strategies to reduce urinary oxalate excretion are reviewed. PMID:26614109

Aldosterone Is Not Associated With Metabolic and Microvascular Insulin Sensitivity in Abdominally Obese Men.

PubMed

Schütten, Monica T J; Kusters, Yvo H A M; Houben, Alfons J H M; Scheijen, Jean L J M; van de Waarenburg, Marjo P H; Schalkwijk, Casper G; Joris, Peter J; Plat, Jogchum; Mensink, Ronald P; de Leeuw, Peter W; Stehouwer, Coen D A

2018-02-01

Impaired insulin-mediated muscle microvascular recruitment (IMMR) may add to the development of insulin resistance and hypertension. Increased aldosterone levels have been linked to these obesity-related complications in severely to morbidly obese individuals and to impaired microvascular function in experimental studies. To investigate whether aldosterone levels are associated with IMMR, insulin sensitivity, and blood pressure in lean and moderately abdominally obese men, and to study the effect of weight loss. In 25 lean and 53 abdominally obese men, 24-hour blood pressure measurement was performed, and aldosterone levels were measured using ultra-performance liquid chromatography tandem mass spectrometry. Insulin sensitivity was assessed by determining whole-body glucose disposal during a hyperinsulinemic clamp. IMMR in forearm skeletal muscle was measured with contrast-enhanced ultrasonography. These assessments were repeated in the abdominally obese men following an 8-week weight loss or weight stable period. Sodium excretion and aldosterone levels were similar in lean and abdominally obese participants, but sodium excretion was inversely associated with aldosterone concentration only in the lean individuals [lean, β/100 mmol sodium excretion (adjusted for age and urinary potassium excretion) = -0.481 (95% confidence interval, -0.949 to -0.013); abdominally obese, β/100 mmol sodium excretion = -0.081 (95% confidence interval, -0.433 to 0.271); P for interaction = 0.02]. Aldosterone was not associated with IMMR, insulin sensitivity, or blood pressure and was unaffected by weight loss. In moderately abdominally obese men, the inverse relationship between sodium excretion and aldosterone concentration is less than that in lean men but does not translate into higher aldosterone levels. The absolute aldosterone level does not explain differences in microvascular and metabolic insulin sensitivity and blood pressure between lean and moderately abdominally obese men. Copyright © 2017 Endocrine Society

Adaptation to abrupt time shifts of the oscillator(s) controlling human circadian rhythms.

PubMed Central

Mills, J N; Minors, D S; Waterhouse, J M

1978-01-01

1. Thirty-six subjects in an isolation unit were subjected to time shifts of 12 hr, or of 8 hr in either direction. 2. The rhythms of body temperature and excretion of eight urinary constituents were studied before and after the shift, both on a usual nychthemeral routine and during 24 hr when they remained under constant conditions, awake, engaged in light, mainly sedentary activity, and consuming identical food and fluid every hour. 3. The rhythms on nychthemeral routine were defined by fitting cosine curves. On constant routine the rhythm after the shift was cross-correlated with the original rhythm, either with variable delay (or advance) or with an additive mixture between this variably shifted rhythm and the unshifted or a fully shifted rhythm. The process yielding the highest correlation coefficient was accepted as the best descriptor of the nature of adaptation. 4. A combination of two rhythms was observed more often for urinary sodium, chloride and phosphate than for other variables. 5. Adaptation appeared to have proceeded further after westward than eastward shifts, and this difference was particularly noticeable for urinary potassium, sodium and chloride. 6. Partial adaptation usually involved a phase delay, even after an eastward shift when a cumulative delay of 16 hr would be needed to achieve full adaptation and re-entrainment. 7. Observations under nychthemeral conditions often gave a false idea of the degree of adaptation. In particular, after an eastward shift the phase of the rhythms appeared to shift in the appropriate direction when studied under nychthemeral conditions whereas the endogenous oscillator either showed no consistent behaviour or, in the control of urate excretion, a shift in the wrong direction. 8. The implications for people undergoing time shifts, in the course of shift work or transmeridional flights, are indicated. PMID:745108

Effect of zeolite nano-materials and artichoke (Cynara scolymus L.) leaf extract on increase in urinary clearance of systematically absorbed nicotine.

PubMed

Malekshah, R E; Mahjub, R; Rastgarpanah, M; Ghorbani, M; Partoazar, A R; Mehr, S E; Dehpour, A R; Dorkoosh, F A

2012-12-01

Nicotine, the main pharmacologically active component in tobacco and cigarette, has some toxic effects and also high potential for addiction. In this study, the effect of artichoke (Cynara scolymus L.) and zeolite nano-materials on urinary excretion of nicotine and consequently elimination of systematically absorbed nicotine was investigated. A simple, valid and highly sensitive high performance liquid chromatography method has been developed for determination of nicotine in rat urine according to guidelines for bioanalysis.It was found that nano-zeolites can cause increase in urinary concentration of nicotine due to its high surface adsorption. Artichoke leaf extract can cause increase in urinary excretion of nicotine in longer post administration times. It was observed that co-administration of nanozeolites and the leaf extract has the synergetic effect on increasing the urinary excretion of nicotine. © Georg Thieme Verlag KG Stuttgart · New York.

Diabetic kidney disease in FVB/NJ Akita mice: temporal pattern of kidney injury and urinary nephrin excretion.

PubMed

Chang, Jae-Hyung; Paik, Seung-Yeol; Mao, Lan; Eisner, William; Flannery, Patrick J; Wang, Liming; Tang, Yuping; Mattocks, Natalie; Hadjadj, Samy; Goujon, Jean-Michel; Ruiz, Phillip; Gurley, Susan B; Spurney, Robert F

2012-01-01

Akita mice are a genetic model of type 1 diabetes. In the present studies, we investigated the phenotype of Akita mice on the FVB/NJ background and examined urinary nephrin excretion as a marker of kidney injury. Male Akita mice were compared with non-diabetic controls for functional and structural characteristics of renal and cardiac disease. Podocyte number and apoptosis as well as urinary nephrin excretion were determined in both groups. Male FVB/NJ Akita mice developed sustained hyperglycemia and albuminuria by 4 and 8 weeks of age, respectively. These abnormalities were accompanied by a significant increase in systolic blood pressure in 10-week old Akita mice, which was associated with functional, structural and molecular characteristics of cardiac hypertrophy. By 20 weeks of age, Akita mice developed a 10-fold increase in albuminuria, renal and glomerular hypertrophy and a decrease in the number of podocytes. Mild-to-moderate glomerular mesangial expansion was observed in Akita mice at 30 weeks of age. In 4-week old Akita mice, the onset of hyperglycemia was accompanied by increased podocyte apoptosis and enhanced excretion of nephrin in urine before the development of albuminuria. Urinary nephrin excretion was also significantly increased in albuminuric Akita mice at 16 and 20 weeks of age and correlated with the albumin excretion rate. These data suggest that: 1. FVB/NJ Akita mice have phenotypic characteristics that may be useful for studying the mechanisms of kidney and cardiac injury in diabetes, and 2. Enhanced urinary nephrin excretion is associated with kidney injury in FVB/NJ Akita mice and is detectable early in the disease process.

Diabetic Kidney Disease in FVB/NJ Akita Mice: Temporal Pattern of Kidney Injury and Urinary Nephrin Excretion

PubMed Central

Chang, Jae-Hyung; Paik, Seung-Yeol; Mao, Lan; Eisner, William; Flannery, Patrick J.; Wang, Liming; Tang, Yuping; Mattocks, Natalie; Hadjadj, Samy; Goujon, Jean-Michel; Ruiz, Phillip; Gurley, Susan B.; Spurney, Robert F.

2012-01-01

Akita mice are a genetic model of type 1 diabetes. In the present studies, we investigated the phenotype of Akita mice on the FVB/NJ background and examined urinary nephrin excretion as a marker of kidney injury. Male Akita mice were compared with non-diabetic controls for functional and structural characteristics of renal and cardiac disease. Podocyte number and apoptosis as well as urinary nephrin excretion were determined in both groups. Male FVB/NJ Akita mice developed sustained hyperglycemia and albuminuria by 4 and 8 weeks of age, respectively. These abnormalities were accompanied by a significant increase in systolic blood pressure in 10-week old Akita mice, which was associated with functional, structural and molecular characteristics of cardiac hypertrophy. By 20 weeks of age, Akita mice developed a 10-fold increase in albuminuria, renal and glomerular hypertrophy and a decrease in the number of podocytes. Mild-to-moderate glomerular mesangial expansion was observed in Akita mice at 30 weeks of age. In 4-week old Akita mice, the onset of hyperglycemia was accompanied by increased podocyte apoptosis and enhanced excretion of nephrin in urine before the development of albuminuria. Urinary nephrin excretion was also significantly increased in albuminuric Akita mice at 16 and 20 weeks of age and correlated with the albumin excretion rate. These data suggest that: 1. FVB/NJ Akita mice have phenotypic characteristics that may be useful for studying the mechanisms of kidney and cardiac injury in diabetes, and 2. Enhanced urinary nephrin excretion is associated with kidney injury in FVB/NJ Akita mice and is detectable early in the disease process. PMID:22496773

Urinary sodium excretion after gastric bypass surgery.

PubMed

Docherty, Neil G; Fändriks, Lars; le Roux, Carel W; Hallersund, Peter; Werling, Malin

2017-09-01

Gut-kidney signaling is implicated in sodium homeostasis and thus blood pressure regulation. Roux-en-Y gastric bypass (RYGB) surgery for morbid obesity confers a pronounced and long-lasting blood pressure lowering effect in addition to significant weight loss. We set out to establish whether RYGB is associated with an intrinsic change in urinary sodium excretion that may contribute to the reported blood pressure lowering effects of the procedure. University hospital METHODS: Five female patients (age range: 28-50 yr) without metabolic or hypertensive co-morbidities were included in a study involving four 24-hour residential visits: once before surgery and 10 days, 3 months, and 20 months after surgery. Creatinine and sodium were measured in fasting plasma samples and 24-hour urine samples and creatinine clearance, estimated glomerular filtration rate, and indices of urinary sodium excretion were calculated. Fasting and 60-minute postprandial blood samples from each study day were assayed for pro-B-type natriuretic peptide (NT-proBNP). Increases in weight-normalized urinary sodium excretion of up to 2.3-fold in magnitude occurred at 20 months after surgery. Median fractional excretion of sodium at 20 months was double that seen before surgery. Fasting NT-proBNP levels were stable or increased (1.5- to 5-fold). Moreover, a small postprandial increase in NT-proBNP was observed after surgery. Renal fractional excretion of sodium is increased after RYGB. A shift toward increased postoperative basal and meal associated levels of NT-proBNP coincides with increased urinary sodium excretion. The data support a working hypothesis that an enhanced natriuretic gut-kidney signal after RYGB may be of mechanistic importance in the blood pressure lowering effects of this procedure. Copyright © 2017 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

Excess Vitamin Intake before Starvation does not Affect Body Mass, Organ Mass, or Blood Variables but Affects Urinary Excretion of Riboflavin in Starving Rats.

PubMed

Moriya, Aya; Fukuwatari, Tsutomu; Shibata, Katsumi

2013-01-01

B-vitamins are important for producing energy from amino acids, fatty acids, and glucose. The aim of this study was to elucidate the effects of excess vitamin intake before starvation on body mass, organ mass, blood, and biological variables as well as on urinary excretion of riboflavin in rats. Adult rats were fed two types of diets, one with a low vitamin content (minimum vitamin diet for optimum growth) and one with a sufficient amount of vitamins (excess vitamin diet). Body mass, organ mass, and blood variables were not affected by excess vitamin intake before starvation. Interestingly, urinary riboflavin excretion showed a different pattern. Urine riboflavin in the excess vitamin intake group declined gradually during starvation, whereas it increased in the low vitamin intake group. Excess vitamin intake before starvation does not affect body mass, organ mass, or blood variables but does affect the urinary excretion of riboflavin in starving rats.

Use of the Method of Triads in the Validation of Sodium and Potassium Intake in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

PubMed Central

Pereira, Taísa Sabrina Silva; Cade, Nágela Valadão; Mill, José Geraldo; Sichieri, Rosely; Molina, Maria del Carmen Bisi

2016-01-01

Introduction Biomarkers are a good choice to be used in the validation of food frequency questionnaire due to the independence of their random errors. Objective To assess the validity of the potassium and sodium intake estimated using the Food Frequency Questionnaire ELSA-Brasil. Subjects/Methods A subsample of participants in the ELSA-Brasil cohort was included in this study in 2009. Sodium and potassium intake were estimated using three methods: Semi-quantitative food frequency questionnaire, 12-hour nocturnal urinary excretion and three 24-hour food records. Correlation coefficients were calculated between the methods, and the validity coefficient was calculated using the method of triads. The 95% confidence intervals for the validity coefficient were estimated using bootstrap sampling. Exact and adjacent agreement and disagreement of the estimated sodium and potassium intake quintiles were compared among three methods. Results The sample consisted of 246 participants, aged 53±8 years, 52% of women. Validity coefficient for sodium were considered weak (рfood frequency questionnaire actual intake = 0.37 and рbiomarker actual intake = 0.21) and moderate (рfood records actual intake 0.56). The validity coefficient were higher for potassium (рfood frequency questionnaire actual intake = 0.60; рbiomarker actual intake = 0.42; рfood records actual intake = 0.79). Conclusions: The Food Frequency Questionnaire ELSA-Brasil showed good validity in estimating potassium intake in epidemiological studies. For sodium validity was weak, likely due to the non-quantification of the added salt to prepared food. PMID:28030625

Use of the Method of Triads in the Validation of Sodium and Potassium Intake in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

PubMed

Pereira, Taísa Sabrina Silva; Cade, Nágela Valadão; Mill, José Geraldo; Sichieri, Rosely; Molina, Maria Del Carmen Bisi

2016-01-01

Biomarkers are a good choice to be used in the validation of food frequency questionnaire due to the independence of their random errors. To assess the validity of the potassium and sodium intake estimated using the Food Frequency Questionnaire ELSA-Brasil. A subsample of participants in the ELSA-Brasil cohort was included in this study in 2009. Sodium and potassium intake were estimated using three methods: Semi-quantitative food frequency questionnaire, 12-hour nocturnal urinary excretion and three 24-hour food records. Correlation coefficients were calculated between the methods, and the validity coefficient was calculated using the method of triads. The 95% confidence intervals for the validity coefficient were estimated using bootstrap sampling. Exact and adjacent agreement and disagreement of the estimated sodium and potassium intake quintiles were compared among three methods. The sample consisted of 246 participants, aged 53±8 years, 52% of women. Validity coefficient for sodium were considered weak (рfood frequency questionnaire actual intake = 0.37 and рbiomarker actual intake = 0.21) and moderate (рfood records actual intake 0.56). The validity coefficient were higher for potassium (рfood frequency questionnaire actual intake = 0.60; рbiomarker actual intake = 0.42; рfood records actual intake = 0.79). Conclusions: The Food Frequency Questionnaire ELSA-Brasil showed good validity in estimating potassium intake in epidemiological studies. For sodium validity was weak, likely due to the non-quantification of the added salt to prepared food.

Dental hyponatraemia.

PubMed

Simpson, R M

2011-08-01

A 14-year-old girl developed dental pain and was treated for acute infected pulpitis of her right upper lateral incisor with drilling and filling. The pain continued and was helped by analgesia, sucking ice cubes and drinking cold water. Forty-eight hours later, she became confused and disoriented. She started to vomit and complained of headache. Investigations revealed hyponatraemia with normal serum potassium levels and initially normal urinary sodium excretion. Over the next 24 hours, she passed 5.45 L of urine and her serum sodium rose from 125 to 143 mmol/L. Self-induced water intoxication has been described during drinking games and initiation ceremonies, but this would appear to an unusual cause. Conservative management proved successful in allowing this girl to recover without sequelae.

Adult presentation of Bartter syndrome type IV with erythrocytosis

PubMed Central

Heilberg, Ita Pfeferman; Tótoli, Cláudia; Calado, Joaquim Tomaz

2015-01-01

Abstract Bartter syndrome comprises a group of rare autosomal-recessive salt-losing disorders with distinct phenotypes, but one unifying pathophysiology consisting of severe reductions of sodium reabsorption caused by mutations in five genes expressed in the thick ascending limb of Henle, coupled with increased urinary excretion of potassium and hydrogen, which leads to hypokalemic alkalosis. Bartter syndrome type IV, caused by loss-of-function mutations in barttin, a subunit of chloride channel CLC-Kb expressed in the kidney and inner ear, usually occurs in the antenatal-neonatal period. We report an unusual case of late onset presentation of Bartter syndrome IV and mild phenotype in a 20 years-old man who had hypokalemia, deafness, secondary hyperparathyroidism and erythrocytosis. PMID:26537508

Blood pressure, ethnic group, and salt intake in Belize.

PubMed

Simmons, D

1983-03-01

A total of 1316 individuals were studied in seven villages in Belize, Central America. This represented 92% of the area population aged over 18. Generally, they were members of three ethnic groups--Maya, Spanish, and Creole. The systolic and diastolic IV and V blood pressures were recorded using standardised procedure. Significant differences in blood pressure, weight, and obesity were found between ethnic groups in both sexes, Creoles having higher means than the other groups. Significant relationships with blood pressure were found with obesity, age, and number of children. An early morning urine specimen was obtained from a random 50% of the men, and only in Creoles was there an association between raised blood pressure and sodium/potassium urinary excretion ratio.

Direct radioimmunoassay of urinary estrogen and pregnanediol glucuronides during the menstrual cycle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stanczyk, F.Z.; Miyakawa, I.; Goebelsmann, U.

Assays measuring immunoreactive estrone glucuronide (E/sub 1/G), estradiol-3-glucuronide (E/sub 2/-3G), estradiol-17..beta..-glucuronide (E/sub 2/-17G), estriol-3-glucuronide (E/sub 3/-3G), estriol-16..cap alpha..-glucuronide (E/sub 3/-16G), and pregnanediol-3..cap alpha..-glucuronide (Pd-3G) directly in diluted urine were developed and validated. These estrogen and pregnanediol glucuronide fractions were measured in aliquots of 24-hour and overnight samples of urine collected daily from seven women for one menstrual cycle. Urinary hormone excretion was correlated with daily serum estradiol (E/sub 2/), progesterone (P), and lutenizing hormonee (LH) levels. A sharp midcycle LH peak preceded by a preovulatory rise in serum E/sub 2/ and followed by luteal phase serum P levels were notedmore » in each of the seven apparently ovulatory cycles. Twenty-four-hour and overnight urinary excretion patterns of estrogen glucuronides were similar to those of serum E/sub 2/. Of the five estrogen glucuronide fractions tested, excretion of E/sub 2/-17G exhibited the earliest and steepest ascending slope of the preovulatory estrogen surge and correlated best with serum E/sub 2/ levels. Urinary excretion of E/sub 1/-G, E/sub 2/-3G, and E/sub 3/-16G also showed an early and steep preovulatory rise and preceded that of E/sub 3/-3G, whereas urinary excretion of E/sub 3/-3G exhibited the poorest correlation with serum E/sub 2/ concentrations. The urinary excretion of Pd-3G rose parallel to serum P levels and was markedly elevated 2 to 3 days after the midcycle LH peak in both 24-hour and overnight collections of urine. These results indicate that among the urinary estrogen conjugate fractions tested, E/sub 2/-17G is the one that most suitably predicts ovulation.« less

Assessment of Urinary Betaine as a Marker of Diabetes Mellitus in Cardiovascular Patients

PubMed Central

Schartum-Hansen, Hall; Ueland, Per M.; Pedersen, Eva R.; Meyer, Klaus; Ebbing, Marta; Bleie, Øyvind; Svingen, Gard F. T.; Seifert, Reinhard; Vikse, Bjørn E.; Nygård, Ottar

2013-01-01

Abnormal urinary excretion of betaine has been demonstrated in patients with diabetes or metabolic syndrome. We aimed to identify the main predictors of excretion in cardiovascular patients and to make initial assessment of its feasibility as a risk marker of future diabetes development. We used data from 2396 patients participating in the Western Norway B-vitamin Intervention Trial, who delivered urine and blood samples at baseline, and in the majority at two visits during follow-up of median 39 months. Betaine in urine and plasma were measured by liquid-chromatography-tandem mass spectrometry. The strongest determinants of urinary betaine excretion by multiple regression were diabetes mellitus, age and estimated glomerular filtration rate; all p<0.001. Patients with diabetes mellitus (n = 264) had a median excretion more than three times higher than those without. We found a distinct non-linear association between urinary betaine excretion and glycated hemoglobin, with a break-point at 6.5%, and glycated hemoglobin was the strongest determinant of betaine excretion in patients with diabetes mellitus. The discriminatory power for diabetes mellitus corresponded to an area under the curve by receiver-operating characteristics of 0.82, and betaine excretion had a coefficient of reliability of 0.73. We also found a significant, independent log-linear relation between baseline betaine excretion and the risk of developing new diabetes during follow-up. The good discriminatory power for diabetes, high test-retest stability and independent association with future risk of new diabetes should motivate further investigation on the role of betaine excretion in risk assessment and long-term follow-up of diabetes mellitus. PMID:23936331

Urinary excretion of purine derivatives as an index of microbial protein synthesis in the camel (Camelus dromedarius).

PubMed

Guerouali, Abdelhai; El Gass, Youssef; Balcells, Joaquim; Belenguer, Alvaro; Nolan, John

2004-08-01

Five experiments were carried out to extend knowledge of purine metabolism in the camel (Camelus dromedarius) and to establish a model to enable microbial protein outflow from the forestomachs to be estimated from the urinary excretion of purine derivatives (PD; i.e. xanthine, hypoxanthine, uric acid, allantoin). In experiment 1, four camels were fasted for five consecutive days to enable endogenous PD excretion in urine to be determined. Total PD excretion decreased during the fasting period to 267 (SE 41.5) micromol/kg body weight (W)0.75 per d. Allantoin and xanthine + hypoxanthine were consistently 86 and 6.1 % of total urinary PD during this period but uric acid increased from 3.6 % to 7.4 %. Xanthine oxidase activity in tissues (experiment 2) was (micromol/min per g fresh tissue) 0.038 in liver and 0.005 in gut mucosa but was not detected in plasma. In experiment 3, the duodenal supply of yeast containing exogenous purines produced a linear increase in urinary PD excretion rate with the slope indicating that 0.63 was excreted in urine. After taking account of endogenous PD excretion, the relationship can be used to predict purine outflow from the rumen. From the latter prediction, and also the purine:protein ratio in bacteria determined in experiment 5, we predicted the net microbial outflow from the rumen. In experiment 4, with increasing food intake, the rate of PD excretion in the urine increased linearly by about 11.1 mmol PD/kg digestible organic matter intake (DOMI), equivalent to 95 g microbial protein/kg DOMI.

Acidosis and Urinary Calcium Excretion: Insights from Genetic Disorders

PubMed Central

Cordat, Emmanuelle; Chambrey, Régine; Dimke, Henrik; Eladari, Dominique

2016-01-01

Metabolic acidosis is associated with increased urinary calcium excretion and related sequelae, including nephrocalcinosis and nephrolithiasis. The increased urinary calcium excretion induced by metabolic acidosis predominantly results from increased mobilization of calcium out of bone and inhibition of calcium transport processes within the renal tubule. The mechanisms whereby acid alters the integrity and stability of bone have been examined extensively in the published literature. Here, after briefly reviewing this literature, we consider the effects of acid on calcium transport in the renal tubule and then discuss why not all gene defects that cause renal tubular acidosis are associated with hypercalciuria and nephrocalcinosis. PMID:27468975

Increased urinary excretion of platelet activating factor in mice with lupus nephritis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Macconi, D.; Noris, M.; Benfenati, E.

1991-01-01

Platelet activating factor (PAF) is present in urine from humans and experimental animals in normal conditions. Very little is known about changes in PAF urinary excretion under pathologic conditions and no data are available about the origin of PAF in the urine. In the present study we explored the possibility that immunologic renal disease is associated with an increase in PAF urinary excretion using gas chromatography-mass spectrometry technique. To clarify the renal or extrarenal origin of urinary PAF we evaluated whether exogenously administered PAF (1-(1{prime},2{prime}-{sup 3}H)alkyl) is filtered through the glomerulus and excreted in the urine. The results show that:more » (1) urine from mice with lupus nephritis in the early phase of the disease contained amounts of PAF comparable to those excreted in normal mouse urine, (2) PAF levels increased when animals started to develop high grade proteinuria, (3) after intravenous injection of ({sup 3}H) PAF In nephritic mice, a negligible amount of ({sup 3}H) ether lipid, corresponding to ({sup 3}H)1-alkyl -2-acyl-3-phosphocholine (alkyl-2-acyl-GPC), was recovered from the 24 h urine extract.« less

Changes in urinary risk profile after short-term low sodium and low calcium diet in recurrent Swiss kidney stone formers.

PubMed

Seeger, Harald; Kaelin, Andrea; Ferraro, Pietro M; Weber, Damian; Jaeger, Philippe; Ambuehl, Patrice; Robertson, William G; Unwin, Robert; Wagner, Carsten A; Mohebbi, Nilufar

2017-12-04

Kidney stone disease is common in industrialized countries. Recently, it has attracted growing attention, because of its significant association with adverse renal outcomes, including end stage renal disease. Calcium-containing kidney stones are frequent with high recurrence rates. While hypercalciuria is a well-known risk factor, restricted intake of animal protein and sodium, combined with normal dietary calcium, has been shown to be more effective in stone prevention compared with a low-calcium diet. Notably, the average sodium intake in Switzerland is twice as high as the WHO recommendation, while the intake of milk and dairy products is low. We retrospectively analyzed Swiss recurrent kidney stone formers (rKSF) to test the impact of a low-sodium in combination with a low-calcium diet on the urinary risk profile. In patients with recurrent calcium oxalate containing stones, we investigated both, the consequence of a low-sodium diet on urinary volume and calcium excretion, and the influence of a low-sodium low-calcium diet on urinary oxalate excretion. Of the 169 patients with CaOx stones, 49 presented with hypercalciuria at baseline. The diet resulted in a highly significant reduction in 24-h urinary sodium and calcium excretion: from 201 ± 89 at baseline to 128 ± 88 mmol/d for sodium (p < 0.0001), and from 5.67 ± 3.01 to 4.06 ± 2.46 mmol/d (p < 0.0001) for calcium, respectively. Urine volume remained unchanged. Notably, no increase in oxalate excretion occurred on the restricted diet (0.39 ± 0.26 vs 0.39 ± 0.19 mmol/d, p = 0.277). Calculated Psf (probability of stone formation) values were only predictive for the risk of calcium phosphate stones. A diet low in sodium and calcium in recurrent calcium oxalate stone formers resulted in a significant reduction of urinary calcium excretion, but no change in urine volume. In this population with apparently low intake of dairy products, calcium restriction does not necessarily result in increased urinary oxalate excretion. However, based on previous studies, we recommend a normal dietary calcium intake to avoid a potential increase in urinary oxalate excretion and unfavorable effects on bone metabolism in hypercalciuric KSFs.

Effect of Roux-en-Y gastric bypass and diet-induced weight loss on diabetic kidney disease in the Zucker diabetic fatty rat.

PubMed

Neff, Karl J; Elliott, Jessie A; Corteville, Caroline; Abegg, Kathrin; Boza, Camilo; Lutz, Thomas A; Docherty, Neil G; le Roux, Carel W

2017-01-01

Reductions in urinary protein excretion after Roux-en-Y gastric bypass (RYGB) surgery in patients with diabetic kidney disease have been reported in multiple studies. To determine the weight loss dependence of the effect of RYGB on urinary protein excretion by comparing renal outcomes in Zucker diabetic fatty rats undergoing either gastric bypass surgery or a sham operation with or without weight matching. University laboratories. Zucker diabetic fatty rats underwent surgery at 18 weeks of age. A subgroup of sham operated rats were weight matched to RYGB operated rats by restricting food intake. Urinary protein excretion was assessed at baseline and at postoperative weeks 4 and 12. Renal histology and macrophage-associated inflammation were assessed at postoperative week 12. Progressive urinary protein excretion was attenuated by both RYGB and diet-induced weight loss, albeit to a lesser extent by the latter. Both weight loss interventions produced equivalent reductions in glomerulomegaly, glomerulosclerosis, and evidence of renal macrophage infiltration. Weight loss per se improves renal structure and attenuates renal inflammatory responses in an experimental animal model of diabetic kidney disease. Better glycemic control post-RYGB may in part explain the greater reductions in urinary protein excretion after gastric bypass surgery. Copyright © 2017 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

Low Impact of Urinary Cortisol in the Assessment of Hydrocortisone Replacement Therapy.

PubMed

Haas, C S; Rahvar, A-H; Danneberg, S; Lehnert, H; Moenig, H; Harbeck, B

2016-09-01

Hydrocortisone replacement therapy is a cornerstone in the treatment of adrenal insufficiency (AI). While urinary cortisol has been used as a diagnostic tool for AI, it remains unclear whether it is a useful parameter to monitor hydrocortisone replacement therapy. Aim of this study was to evaluate possible differences in cortisol metabolism between adrenal insufficient patients and healthy subjects and to assess the value of urinary cortisol in AI management. In a case-control study, urinary cortisol excretion was determined in 14 patients with primary and secondary AI receiving hydrocortisone infusions from midnight to 8:00 AM. Results were correlated with serum cortisol levels and compared to urinary values obtained from 53 healthy volunteers. Urinary cortisol excretion in healthy subjects was 14.0±7.8 μg/8 h (range: 0.24-35.4), levels did not differ between 3 groups aged 20-34 years, 35-49 years, and ≥50 years. Patients with AI receiving hydrocortisone infusions demonstrated significantly higher rates of urinary cortisol excretion (51.6±37.8 μg/8 h; range 17.1-120.0, p<0.001); the values correlated with serum cortisol levels (r(2)=0.98). Of interest, patients with secondary AI showed significantly higher serum cortisol levels after hydrocortisone infusion than those with primary AI, conceivably due to residual adrenal function. In conclusion, we showed that: (i) there is a wide inter-individual variability in urinary cortisol excretion rates; (ii) cortisol metabolism in adrenal insufficient patients differs when compared to controls; (iii) there is a strong correlation between urinary and serum cortisol levels; and (iv) urinary cortisol levels despite their variability may help to discriminate between secondary and primary adrenal insufficiency. © Georg Thieme Verlag KG Stuttgart · New York.

Hypertension and Hyperglycemia Synergize to Cause Incipient Renal Tubular Alterations Resulting in Increased NGAL Urinary Excretion in Rats

PubMed Central

Blázquez-Medela, Ana M.; García-Sánchez, Omar; Blanco-Gozalo, Víctor; Quiros, Yaremi; Montero, María J.; Martínez-Salgado, Carlos; López-Novoa, José M.; López-Hernández, Francisco J.

2014-01-01

Background Hypertension and diabetes are the two leading causes of chronic kidney disease (CKD) eventually leading to end stage renal disease (ESRD) and the need of renal replacement therapy. Mortality among CKD and ESRD patients is high, mostly due to cardiovascular events. New early markers of risk are necessary to better anticipate the course of the disease, to detect the renal affection of additive risk factors, and to appropriately handle patients in a pre-emptive and personalized manner. Methods Renal function and NGAL urinary excretion was monitored in rats with spontaneous (SHR) or L-NAME induced hypertension rendered hyperglycemic (or not as controls). Results Combination of hypertension and hyperglycemia (but not each of these factors independently) causes an increased urinary excretion of neutrophil gelatinase-associated lipocalin (NGAL) in the rat, in the absence of signs of renal damage. Increased NGAL excretion is observed in diabetic animals with two independent models of hypertension. Elevated urinary NGAL results from a specific alteration in its tubular handling, rather than from an increase in its renal expression. In fact, when kidneys of hyperglycaemic-hypertensive rats are perfused in situ with Krebs-dextran solution containing exogenous NGAL, they excrete more NGAL in the urine than hypertensive rats. We also show that albuminuria is not capable of detecting the additive effect posed by the coexistence of these two risk factors. Conclusions Our results suggest that accumulation of hypertension and hyperglycemia induces an incipient and quite specific alteration in the tubular handling of NGAL resulting in its increased urinary excretion. PMID:25148248

Hypertension and hyperglycemia synergize to cause incipient renal tubular alterations resulting in increased NGAL urinary excretion in rats.

PubMed

Blázquez-Medela, Ana M; García-Sánchez, Omar; Blanco-Gozalo, Víctor; Quiros, Yaremi; Montero, María J; Martínez-Salgado, Carlos; López-Novoa, José M; López-Hernández, Francisco J

2014-01-01

Hypertension and diabetes are the two leading causes of chronic kidney disease (CKD) eventually leading to end stage renal disease (ESRD) and the need of renal replacement therapy. Mortality among CKD and ESRD patients is high, mostly due to cardiovascular events. New early markers of risk are necessary to better anticipate the course of the disease, to detect the renal affection of additive risk factors, and to appropriately handle patients in a pre-emptive and personalized manner. Renal function and NGAL urinary excretion was monitored in rats with spontaneous (SHR) or L-NAME induced hypertension rendered hyperglycemic (or not as controls). Combination of hypertension and hyperglycemia (but not each of these factors independently) causes an increased urinary excretion of neutrophil gelatinase-associated lipocalin (NGAL) in the rat, in the absence of signs of renal damage. Increased NGAL excretion is observed in diabetic animals with two independent models of hypertension. Elevated urinary NGAL results from a specific alteration in its tubular handling, rather than from an increase in its renal expression. In fact, when kidneys of hyperglycaemic-hypertensive rats are perfused in situ with Krebs-dextran solution containing exogenous NGAL, they excrete more NGAL in the urine than hypertensive rats. We also show that albuminuria is not capable of detecting the additive effect posed by the coexistence of these two risk factors. Our results suggest that accumulation of hypertension and hyperglycemia induces an incipient and quite specific alteration in the tubular handling of NGAL resulting in its increased urinary excretion.

Evolution of urinary iodine excretion over eleven years in an adult population.

PubMed

Gutiérrez-Repiso, Carolina; Colomo, Natalia; Rojo-Martinez, Gemma; Valdés, Sergio; Tapia, Maria J; Esteva, Isabel; Ruiz de Adana, Maria S; Rubio-Martin, Elehazara; Lago-Sampedro, Ana; Santiago, Piedad; Velasco, Ines; Garcia-Fuentes, Eduardo; Moreno, Jose C; Soriguer, Federico

2015-08-01

Few prospective cohort studies have evaluated dietary iodine intake and urinary iodine concentrations in the general adult population. We assess the evolution of urinary iodine excretion and factors that may influence it in an adult population followed for 11 years. A population-based cohort study was undertaken in Pizarra (Spain). In the three study phases (baseline (n = 886), and 6 (n = 788) and 11 years later (n = 501)), participants underwent an interview and a standardized clinical examination that included a food questionnaire, and thyroid hormone and urinary iodine determinations. Subjects with thyroid dysfunction, palpable goiter or urinary iodine excretion >400 μg/L were excluded. Urinary iodine increased over the years (100.6 ± 70.0 μg/L at baseline vs. 125.4 ± 95.2 μg/L at 6 years and 141.6 ± 81.4 μg/L at 11 years; p < 0.0001). Urinary iodine was significantly higher in subjects who reported iodized salt consumption and in subjects with a higher intake of dairy products (p < 0.05). Consumption of iodized salt (Risk ratio (RR) = 1.23, 95% CI [1.01-2.05]) and dairy products (RR = 2.07, 95% CI [1.01-4.23]), and a baseline urinary iodine concentration ≥100 μg/L (RR = 1.26, 95% CI [1.04-1.53]) were significantly associated with urinary iodine concentrations ≥100 μg/L at 11 years. There is no correlation between thyroid function (TSH, free triiodothyronine or free thyroxine levels) and urinary iodine concentrations in conditions of iodine sufficiency. The increase in urinary iodine concentrations over eleven years is associated with an increase in iodized salt intake and with the dairy products intake, and possibly with a higher iodine content of dairy products. However, individual variability in urinary iodine excretion was not fully explained by dietary iodine intake alone; previous urinary iodine concentrations were also important. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

LY3127760, a Selective Prostaglandin E4 (EP4) Receptor Antagonist, and Celecoxib: A Comparison of Pharmacological Profiles

PubMed Central

Smith, Claire; Hu, Leijun; Coutant, David E.; Whitehurst, Kelly; Phipps, Krista; McNearney, Terry Ann; Yang, Xiao; Ackermann, Bradley; Pottanat, Thomas; Landschulz, William

2017-01-01

Abstract Safety, tolerability, and pharmacology profiles of LY3127760, an EP4 antagonist, were explored in healthy subjects in a subject/investigator‐blind, parallel‐group, multiple‐ascending dose study. Cohorts consisted of 13 patients randomized to LY3127760, celecoxib (400 mg), or placebo (9:2:2 ratio) for 28 days. LY3127760 was well tolerated; the most commonly observed adverse events were gastrointestinal, similar to celecoxib. LY3127760 increased release of ex vivo tumor necrosis factor alpha after lipopolysaccharide/prostaglandin E2 stimulation when compared with placebo, suggesting a dose‐dependent blockade of the EP4 receptor. Compared with placebo, 24‐h urinary excretion of prostaglandin E metabolite was modestly increased; prostacyclin metabolite was inhibited; and thromboxane A2 metabolite was unchanged. Effects on sodium and potassium excretion were similar to those of celecoxib. We conclude that LY3127760 demonstrated similar effects on prostacyclin synthesis and renal sodium retention as celecoxib. These data support exploration of LY3127760 at daily doses of 60 mg to 600 mg in phase II trials. This trial's registration number: NCT01968070. PMID:28857461

INFLUENCE OF DIETARY ARSENIC ON URINARY ARSENIC METABOLITE EXCRETION

EPA Science Inventory

Influence of Dietary Arsenic on Urinary Arsenic Metabolite Excretion

Cara L. Carty, M.S., Edward E. Hudgens, B.Sc., Rebecca L. Calderon, Ph.D., M.S.P.H., Richard Kwok, M.S.P.H., Epidemiology and Biomarkers Branch/HSD, NHEERL/US EPA; David J. Thomas, Ph.D., Pharmacokinetics...

[Effects of excess nicotinic acid on growth and the urinary excretion of B-group vitamins and the metabolism of tryptophan in weaning rats].

PubMed

Fukuwatari, Tsutomu; Kurata, Kaori; Shibata, Katsumi

2009-04-01

To determine the tolerable upper intake level of nicotinic acid in humans, we investigated the effects of excess nicotinic acid administration on body weight gain, food intake, and urinary excretion of water-soluble vitamins and the metabolism of tryptophan in weaning rats. The weaning rats were freely fed a niacin-free 20% casein diet (control diet) or the same diet with 0.1%, 0.3% or 0.5% nicotinic acid for 23 days. The excess nicotinic acid intake did not affect body weight gain, food intake, serotonin contents in the brain, stomach and small intestine, or the urinary excretions of water-soluble vitamins. Although excess nicotinic acid did not affect the upper part of the tryptophan-nicotinamide pathway, 0.5% nicotinic acid diet increased the urinary excretion of quinolinic acid. The diet containing more than 0.3% nicotinic acid also increased the urinary excretion of nicotinic acid, which is usually below the limit of detection. As determined from the results of body weight gain and food intake as indices for apparent adverse effects, the no-observed-adverse-effect-level (NOAEL) for nicotinic acid was 0.5% in diet, corresponding to 450 mg/kg body weight/day. As judged from in increase of urinary quinolinic acid and nicotinic acid as indices of metabolic change, NOAEL was 0.1% in diet, corresponding to 90 mg/kg body weight/day, and the lowest-observed-adverse-effect-level (LOAEL) was 0.3% in diet, corresponding to 270 mg/kg body weight/day.

Mangiferin Inhibits Renal Urate Reabsorption by Modulating Urate Transporters in Experimental Hyperuricemia.

PubMed

Yang, Hua; Gao, Lihui; Niu, Yanfen; Zhou, Yuanfang; Lin, Hua; Jiang, Jing; Kong, Xiangfu; Liu, Xu; Li, Ling

2015-01-01

Mangiferin, a natural glucosyl xanthone from the leaves of Mangifera indica L., was previously shown to exert potent hypouricemic effects associated with inhibition of the activity of xanthine dehydrogenase/oxidase. The present study aimed to evaluate its uricosuric effect and possible molecular mechanisms underlying the renal urate transporters responsible for urate reabsorption in vivo. Mangiferin (1.5-24.0 mg/kg) was administered intragastrically to hyperuricemic mice and rats induced by the intraperitoneal injection of uric acid and potassium oxonate, respectively. The uricosuric effect was evaluated by determining the serum and urinary urate levels as well as fractional excretion of uric acid (FEUA). The mRNA and protein levels of renal urate-anion transporter 1 (URAT1), organic anion transporter 10 (OAT10), glucose transporter 9 (GLUT9), and PDZ domain-containing protein (PDZK1) were analyzed. The administration of mangiferin significantly decreased the serum urate levels in hyperuricemic mice in a dose- and time-dependent manner. In hyperuricemic rats, mangiferin also reduced the serum urate levels and increased the urinary urate levels and FEUA. These results indicate that mangiferin has uricosuric effects. Further examination showed that mangiferin markedly inhibited the mRNA and protein expression of renal URAT1, OAT10, and GLUT9 in hyperuricemic rats, but did not interfere with PDZK1 expression. Taken together, these findings suggest that mangiferin promotes urate excretion by the kidney, which may be related to the inhibition of urate reabsorption via downregulation of renal urate transporters.

Urinary Excretion of Sodium, Nitrogen, and Sugar Amounts Are Valid Biomarkers of Dietary Sodium, Protein, and High Sugar Intake in Nonobese Adolescents.

PubMed

Moore, Lori B; Liu, Sarah V; Halliday, Tanya M; Neilson, Andrew P; Hedrick, Valisa E; Davy, Brenda M

2017-12-01

Background: Objective indicators of dietary intake (e.g., biomarkers) are needed to overcome the limitations of self-reported dietary intake assessment methods in adolescents. To our knowledge, no controlled feeding studies to date have evaluated the validity of urinary sodium, nitrogen, or sugar excretion as dietary biomarkers in adolescents. Objective: This investigation aimed to evaluate the validity of urinary sodium, nitrogen, and total sugars (TS) excretion as biomarkers for sodium, protein, and added sugars (AS) intake in nonobese adolescents. Methods: In a crossover controlled feeding study design, 33 adolescents [12-18 y of age, 47 ± 25th percentile (mean ± SD) of body mass index (BMI; in kg/m 2 ) for age] consumed 5% AS [low added sugars (LAS)] and 25% AS [high added sugars (HAS)] isocaloric, macronutrient-matched (55% carbohydrate, 30% fat, and 15% protein) diets for 7 d each, in a randomly assigned order, with a 4-wk washout period between diets. On the final 2 d of each diet period, 24-h urine samples were collected. Thirty-two adolescents completed all measurements (97% retention). Results: Urinary sodium was not different from the expected 90% recovery (mean ± SD: 88% ± 18%, P = 0.50). Urinary nitrogen was correlated with protein intake ( r = 0.69, P < 0.001), although it was below the 80% expected recovery (62% ± 7%, P < 0.001). Urinary TS values were correlated with AS intake during the HAS diet ( r = 0.77, P < 0.001) and had a higher R 2 value of 0.28 than did AS intake ( R 2 = 0.36). TS excretion differed between LAS (0.226 ± 0.09 mg/d) and HAS (0.365 ± 0.16 mg/d) feeding periods ( P < 0.001). Conclusions: Urinary sodium appears to be a valid biomarker for sodium intake in nonobese adolescents. Urinary nitrogen is associated with protein intake, but nitrogen excretion rates were less than previously reported for adults, possibly owing to adolescent growth rates. TS excretion reflects AS at 25% AS intake and was responsive to the change in AS intake. Thus, urinary biomarkers are promising objective indicators of dietary intake in adolescents, although larger-scale feeding trials are needed to confirm these findings. This trial was registered at clinicaltrials.gov as NCT02455388. © 2017 American Society for Nutrition.

The renal TRPV4 channel is essential for adaptation to increased dietary potassium

PubMed Central

Mamenko, Mykola; Boukelmoune, Nabila; Tomilin, Viktor; Zaika, Oleg; Jensen, V. Behrana; O’Neil, Roger G.; Pochynyuk, Oleh

2016-01-01

To maintain potassium homeostasis, kidneys exert flow-dependent potassium secretion to facilitate kaliuresis in response to elevated dietary potassium intake. This process involves stimulation of calcium-activated large conductance maxi-K (BK) channels in the distal nephron, namely the connecting tubule and the collecting duct. Recent evidence suggests that the TRPV4 channel is a critical determinant of flow-dependent intracellular calcium elevations in these segments of the renal tubule. Here, we demonstrate that elevated dietary potassium intake (five percent potassium) increases renal TRPV4 mRNA and protein levels in an aldosterone-dependent manner and causes redistribution of the channel to the apical plasma membrane in native collecting duct cells. This, in turn, leads to augmented TRPV4-mediated flow-dependent calcium ion responses in freshly isolated split-opened collecting ducts from mice fed the high potassium diet. Genetic TRPV4 ablation greatly diminished BK channel activity in collecting duct cells pointing to a reduced capacity to excrete potassium. Consistently, elevated potassium intake induced hyperkalemia in TRPV4 knockout mice due to deficient renal potassium excretion. Thus, regulation of TRPV4 activity in the distal nephron by dietary potassium is an indispensable component of whole body potassium balance. PMID:28187982

Exacerbation of underlying hypothyroidism caused by proteinuria and induction of urinary thyroxine loss: case report and subsequent investigation.

PubMed

Chandurkar, Vikram; Shik, John; Randell, Edward

2008-01-01

To describe a patient with excess urinary thyroxine (T4) excretion and worsening of preexisting hypothyroidism in the setting of nephrotic syndrome and to determine whether excess urinary T4 excretion is present in other patients with proteinuria. We present data regarding the patient's initial presentation, diagnostic studies, and course of her illness. We suspected urinary T4 loss to be the cause of her presentation and analyzed her urine sample for total T4. We also analyzed differences in urinary T4 excretion in 22 patients with proteinuria and 16 control patients without proteinuria. Relevant medical literature is reviewed. A 44-year-old woman presented with a 3-month history of increasing fluid retention, weight gain, and fatigue. She had long-standing hypothyroidism on a stable levothyroxine dosage, 125 mcg/d. She had gained 27 kg and had developed significant edema. She had a grossly elevated thyroid-stimulating hormone level of 91 mIU/L. Her condition worsened, and a urinary protein measurement was 14.06 g/24 h-diagnostic of nephrotic syndrome. The levothyroxine dosage was increased to 225 mcg/d. Urinary total T4 concentration in a 24-hour sample was 59.0 microg/L (83.1 microg/24 h), indicating that a substantial fraction of her orally ingested T4 was lost in urine. Urinary total T4 excretion was significantly higher in patients with proteinuria (mean +/- standard deviation, 18.0 +/- 18.2 microg/L) vs control patients without proteinuria (mean, 3.8 +/- 1.8 microg/L) (P = .0014). In the patient described, urinary T4 loss due to proteinuria and nephrotic syndrome resulted in a severe exacerbation of underlying hypothyroidism.

Urinary thioether of employees of a chemical plant.

PubMed

Vainio, H; Savolainen, H; Kilpikari, I

1978-08-01

The thiols in the morning urine of 224 employees of a chemical plant were determined after alkaline hydrolysis of all urinary thioethers. The highest thioether excretion was found in rubber workers and radial tyre builders in comparison with clerks, plastic monomer mixers and footwear preparers. Smoking and medication tended to increase thioether excretion. Urinary thioether determination may prove to be a valuable tool in assessing exposure to mixtures of chemicals regardless of the route of absorption.

Urinary thioether of employees of a chemical plant.

PubMed Central

Vainio, H; Savolainen, H; Kilpikari, I

1978-01-01

The thiols in the morning urine of 224 employees of a chemical plant were determined after alkaline hydrolysis of all urinary thioethers. The highest thioether excretion was found in rubber workers and radial tyre builders in comparison with clerks, plastic monomer mixers and footwear preparers. Smoking and medication tended to increase thioether excretion. Urinary thioether determination may prove to be a valuable tool in assessing exposure to mixtures of chemicals regardless of the route of absorption. PMID:698138

Supplementation of alfalfa (Medicago sativa) with condensed tannin-containing pellets of sericea lespedeza (Lespedeza cuneata): Effects on ruminant urinary urea excretion and digestibility

USDA-ARS?s Scientific Manuscript database

Some feedstuffs that contain condensed tannins can reduce urinary urea excretion without compromising nutrition for ruminant livestock. This results in reducing environmental impact, improving productivity and enhancing sustainability of ruminant farming operations. In some situations there are adva...

Relationship between plasma uridine and urinary urea excretion.

PubMed

Ka, Tuneyoshi; Inokuchi, Taku; Tamada, Daisuke; Suda, Michio; Tsutsumi, Zenta; Okuda, Chihiro; Yamamoto, Asako; Takahashi, Sumio; Moriwaki, Yuji; Yamamoto, Tetsuya

2010-03-01

To investigate whether the concentration of uridine in plasma is related to the urinary excretion of urea, 45 healthy male subjects with normouricemia and normal blood pressure were studied after providing informed consent. Immediately after collection of 24-hour urine, blood samples were drawn after an overnight fast except for water. The contents of ingested foods during the 24-hour urine collection period were described by the subjects and analyzed by a dietician. Simple regression analysis showed that plasma uridine was correlated with the urinary excretions of urea (R = 0.41, P < .01), uric acid (R = 0.36, P < .05), and uridine (R = 0.30, P < .05), as well as uric acid clearance (R = 0.35, P < .05) and purine intake (R = 0.30, P < .05). In contrast, multiple regression analysis showed a positive relationship only between plasma uridine and urinary excretion of urea. These results suggest that an increase in de novo pyrimidine synthesis leads to an increased concentration of uridine in plasma via nitrogen catabolism in healthy subjects with normouricemia and normal blood pressure. (c) 2010 Elsevier Inc. All rights reserved.

Effect of dietary supplementation of gallic acid on nitrogen balance, nitrogen excretion pattern and urinary nitrogenous constituents in beef cattle.

PubMed

Wei, Chen; Yang, Kai; Zhao, Guangyong; Lin, Shixin; Xu, Zhiwei

2016-10-01

The objective of the trial was to study the effects of dietary supplementation of gallic acid (GA) on nitrogen (N) balance, N excretion pattern and urinary N constituents in beef cattle. In a 4 × 4 Latin square design, four male 30-month-old Simmental cattle (443 ± 22 kg live weight) received four levels of GA (purity ≥ 98.5%), i.e. 0, 5.3, 10.5, 21.1 g/kg DM, added to a basal ration. Each experimental period lasted 17 d, consisting of 12 d adaptation and 5 d sampling. The results showed that supplementation of GA at 5.3, 10.5 or 21.1 g/kg DM did not affect the N balance but regulated the N excretion pattern by increasing the ratio of faecal N/urinary N and decreasing the ratio of urinary urea N/total urinary N in beef cattle fed at maintenance level.

Biochemical diagnosis of phaeochromocytoma: two instructive case reports.

PubMed Central

Stewart, M F; Reed, P; Weinkove, C; Moriarty, K J; Ralston, A J

1993-01-01

The biochemical features of two patients with phaeochromocytomas illustrate the inadvisability of depending on a single group of analytes for the diagnosis. The first case presented as a surgical emergency with retroperitoneal haemorrhage. Biochemical diagnosis was difficult since total 24 hour urinary free catecholamine excretion was within normal limits in two out of three samples, and only marginally raised in the third with an atypical preponderance of adrenaline. Plasma catecholamine concentrations were also normal. But urinary excretion of the catecholamine metabolites, metadrenaline and 4-hydroxy-3-methoxy mandelic acid (HMMA), was consistently raised. In contrast, the second patient presenting with headache and labile hypertension showed normal metabolite excretion in the face of grossly increased free noradrenaline excretion and raised plasma noradrenaline concentrations. It is therefore recommend that, as well as urinary free catecholamines, one group of their main metabolites, the 3-methoxy amines (normetadrenaline and metadrenaline) or HMMA, should routinely be measured whenever a phaeochromocytoma is suspected. PMID:8463426

Renal effects of intrathecally injected tachykinins in the conscious saline-loaded rat: receptor and mechanism of action

PubMed Central

Ding Yuan, Yi; Couture, Réjean

1997-01-01

The effects of intrathecally (i.t.) injected substance P (SP), neurokinin A (NKA), [β-Ala8]NKA (4–10) and [MePhe7]neurokinin B (NKB) at T13 thoracic spinal cord level were investigated on renal excretion of water, sodium and potassium in the conscious saline-loaded rat. Antagonists selective for NK1 (RP 67580), NK2 (SR 48968) and NK3 (R 820; 3-indolylcarbonyl-Hyp-Phg-N(Me)-Bzl) receptors were used to characterize the spinal effect of SP on renal function. Saline gavage (4.5% of the body weight) enhanced renal excretion of water, sodium and potassium over the subsequent hour of measurement. Whereas these renal responses were not affected by 0.65 nmol SP, the dose of 6.5 nmol SP blocked the natriuretic response (aCSF value 3.9±0.8; SP value 0.7±0.3 μmol min−1, P<0.01) as well as the renal excretion of water (aCSF value 48.9±5.8; SP value 14.5±4.0 μl min−1, P<0.01) and potassium (aCSF value 4.8±0.6; SP value 1.5±0.6 μmol min−1, P<0.01) at 30 min post-injection. SP had no significant effect on urinary osmolality. The SP-induced renal inhibitory effects during the first 30 min were abolished in rats subjected to bilateral renal denervation 1 week earlier or in rats injected i.t. 5 min earlier with 6.5 nmol RP 67580. In contrast, the co-injection of SR 48968 and R 820 (6.5 nmol each) did not affect the inhibitory responses to SP. On their own, these antagonists had no direct effect on renal excretion function. Since SP induced only transient changes in mean arterial blood pressure (−18.8±3.8 mmHg at 1 min and +6.3±2.4 mmHg at 5 min post-injection), it is unlikely that the renal effects of SP are due to systemic haemodynamic changes. NKA (6.5 nmol but not 0.65 nmol) produced a transient drop in renal excretion of water (aCSF value 31.2±5.1; NKA value 11.3±4.2 μl min−1, P<0.05), sodium (aCSF value 1.7±0.8; NKA value 0.4±0.2 μmol min−1, P<0.05) and potassium (aCSF value 4.1±0.7; NKA value 1.5±0.4 μmol min−1, P<0.05) at 15 min post-injection. However, the same doses (6.5 nmol) of selective agonists for tachykinin NK2 ([β-Ala8]NKA(4-10)) and NK3 ([MePhe7]NKB) receptors were devoid of renal effects. This study provided functional evidence that tachykinins may be involved in the renal control of water and electrolyte excretion at the level of the rat spinal cord through the activation of NK1 receptors and the sympathetic renal nerve. PMID:9249250

Mobilisation of heavy metals into the urine by CaEDTA: relation to erythrocyte and plasma concentrations and exposure indicators.

PubMed

Araki, S; Aono, H; Murata, K

1986-09-01

To investigate the effects of calcium disodium ethylenediamine tetra-acetate (CaEDTA) on the urinary excretion, erythrocyte, and plasma concentrations and exposure indicators of seven heavy metals, CaEDTA was administered by intravenous infusion to 20 workers exposed to lead, zinc, and copper. The workers' blood lead concentrations ranged from 22 to 59 micrograms/dl (mean 38 micrograms/dl (1.8 mumol/l]. The 24 hour urinary excretion of metals after CaEDTA administration (mobilisation yield) was on average 13 times the background excretion for lead, 11 times for zinc, 3.8 times for manganese, 3.4 times for cadmium, 1.3 times for copper, and 1.1 times for chromium; no significant increase was found for mercury. The mobilisation yield of lead (MPb) was significantly correlated with whole blood and erythrocyte concentrations and the urinary excretion of lead but not with its plasma concentration; similarly, the mobilisation yield of cadmium was significantly correlated with its erythrocyte concentration. In addition, MPb was significantly correlated with intra-erythrocytic enzyme delta-aminolaevulinic acid dehydratase activity and urinary coproporphyrin excretion. The relation between the mobilisation yield of heavy metals and their body burden (and toxic signs) is discussed in the light of these findings.

Mobilisation of heavy metals into the urine by CaEDTA: relation to erythrocyte and plasma concentrations and exposure indicators.

PubMed Central

Araki, S; Aono, H; Murata, K

1986-01-01

To investigate the effects of calcium disodium ethylenediamine tetra-acetate (CaEDTA) on the urinary excretion, erythrocyte, and plasma concentrations and exposure indicators of seven heavy metals, CaEDTA was administered by intravenous infusion to 20 workers exposed to lead, zinc, and copper. The workers' blood lead concentrations ranged from 22 to 59 micrograms/dl (mean 38 micrograms/dl (1.8 mumol/l]. The 24 hour urinary excretion of metals after CaEDTA administration (mobilisation yield) was on average 13 times the background excretion for lead, 11 times for zinc, 3.8 times for manganese, 3.4 times for cadmium, 1.3 times for copper, and 1.1 times for chromium; no significant increase was found for mercury. The mobilisation yield of lead (MPb) was significantly correlated with whole blood and erythrocyte concentrations and the urinary excretion of lead but not with its plasma concentration; similarly, the mobilisation yield of cadmium was significantly correlated with its erythrocyte concentration. In addition, MPb was significantly correlated with intra-erythrocytic enzyme delta-aminolaevulinic acid dehydratase activity and urinary coproporphyrin excretion. The relation between the mobilisation yield of heavy metals and their body burden (and toxic signs) is discussed in the light of these findings. PMID:3092853

Enteric oxalate elimination is induced and oxalate is normalized in a mouse model of primary hyperoxaluria following intestinal colonization with Oxalobacter

PubMed Central

Gjymishka, Altin; Salido, Eduardo C.; Allison, Milton J.; Freel, Robert W.

2011-01-01

Oxalobacter colonization of rat intestine was previously shown to promote enteric oxalate secretion and elimination, leading to significant reductions in urinary oxalate excretion (Hatch et al. Kidney Int 69: 691–698, 2006). The main goal of the present study, using a mouse model of primary hyperoxaluria type 1 (PH1), was to test the hypothesis that colonization of the mouse gut by Oxalobacter formigenes could enhance enteric oxalate secretion and effectively reduce the hyperoxaluria associated with this genetic disease. Wild-type (WT) mice and mice deficient in liver alanine-glyoxylate aminotransferase (Agxt) exhibiting hyperoxalemia and hyperoxaluria were used in these studies. We compared the unidirectional and net fluxes of oxalate across isolated, short-circuited large intestine of artificially colonized and noncolonized mice. In addition, plasma and urinary oxalate was determined. Our results demonstrate that the cecum and distal colon contribute significantly to enteric oxalate excretion in Oxalobacter-colonized Agxt and WT mice. In colonized Agxt mice, urinary oxalate excretion was reduced 50% (to within the normal range observed for WT mice). Moreover, plasma oxalate concentrations in Agxt mice were also normalized (reduced 50%). Colonization of WT mice was also associated with marked (up to 95%) reductions in urinary oxalate excretion. We conclude that segment-specific effects of Oxalobacter on intestinal oxalate transport in the PH1 mouse model are associated with a normalization of plasma oxalate and urinary oxalate excretion in otherwise hyperoxalemic and hyperoxaluric animals. PMID:21163900

Blood plasma response and urinary excretion of nitrite and nitrate in milk-fed calves after oral nitrite and nitrate administration.

PubMed

Hüsler, B R.; Blum, J W.

2001-05-01

There is marked endogenous production of nitrate in young calves. Here we have studied the contribution of exogenous nitrate and nitrite to plasma concentrations and urinary excretion of nitrite and nitrate in milk-fed calves. In experiment 1, calves were fed 0 or 200 &mgr;mol nitrate or nitrite/kg(0.75) or 100 &mgr;mol nitrite plus 100 &mgr;mol nitrate/kg(0.75) with milk for 3 d. In experiment 2, calves were fed 400 &mgr;mol nitrate or nitrite/kg(0.75) with milk for 1 d. Plasma nitrate rapidly and comparably increased after feeding nitrite, nitrate or nitrite plus nitrate. The rise of plasma nitrate was greater if 400 than 200 &mgr;mol nitrate or nitrite/kg(0.75) were fed. Plasma nitrate decreased slowly after the 3-d administration of 200 &mgr;mol nitrate or nitrite/kg(0.75) and reached pre-experimental concentrations 4 d later. Urinary nitrate excretions nearly identically increased if nitrate, nitrite or nitrite plus nitrate were administered and excreted amounts were greater if 400 than 200 &mgr;mol nitrate or nitrite/kg(0.75) were fed. After nitrite ingestion plasma nitrite only transiently increased after 2 and 4 h and urinary excretion rates remained unchanged. Plasma nitrate concentration remained unchanged if milk was not supplemented with nitrite or nitrate. Nitrate concentrations were stable for 24 h after addition of nitrite to full blood in vitro, whereas nitrite concentrations decreased within 2 h. In conclusion, plasma nitrate concentrations and urinary nitrate excretions are enhanced dose-dependently by feeding low amounts of nitrate and nitrite, whereas after ingested nitrite only a transient and small rise of plasma nitrite is observed because of rapid conversion to nitrate.

Triiodothyronine and thyroxine in urine. I. Measurement and application.

PubMed

Shakespear, R A; Burke, C W

1976-03-01

Urinary triiodothyronine (T3) and thyroxine (T4) were measured by RIA, and T4 was also measured by competitive protein binding (CPB). pH 1-hydrolysable conjugates were 48% of total urinary T3, and enzyme- or pH 1-hydrolysable conjugates were 55% and 61% of total urinary T4. The mean unconjugated T3 excretion was 34.3 ng/h (0.99 mug T3/g creatinine) in normal subjects (no day-night rhythm found), 1.56 mug/g in late pregnancy, 0.82 mug/g in neonates (1-12 days), and was also unchanged in persons with high or low thyroxine-binding globulin (TBG). In thyrotoxicosis, mean T3 excretion was 281 ng/h, no values being in the normal range. In primary hypothyroidism it was 18.3 ng/h, but over half the values were in the normal range. The mean urinary unconjugated T4 was 82.2 ng/h (1.37 mug T4/g creatinine) in normal subjects, 1.6 mug/g in neonates, and unchanged in persons with high or low TBG, except that in pregnancy high values were compatible with increases protein excretion. Apparently increased day-time T4 excretion compared with night-time excretion may also be due to changes in protein excretion rate. The mean T4 in thyrotoxicosis was 337 ng/h (12% of values in the normal range) and 32.8 ng/h in primary hypothyroidism (over half the normal range). All the assays, especially that of T4 by CPB gave readings which were incorrect with protein concentrations above 100 mg/l. Urinary T3 and T4 assays for clinical purposes have few practical advantages over serum assays, despite the relationship of urine T3 and T4 to serum unbound levels.

Pantothenic acid deficiency may increase the urinary excretion of 2-oxo acids and nicotinamide catabolites in rats.

PubMed

Shibata, Katsumi; Inomoto, Kasumi; Nakata, Chifumi; Fukuwatari, Tsutomu

2013-01-01

Pantothenic acid (PaA) is involved in the metabolism of amino acids as well as fatty acid. We investigated the systemic metabolism of amino acids in PaA-deficient rats. For this purpose, urine samples were collected and 2-oxo acids and L-tryptophan (L-Trp) and its metabolites including nicotinamide were measured. Group 1 was freely fed a conventional chemically-defined complete diet and used as an ad lib-fed control, which group was used for showing reference values. Group 2 was freely fed the complete diet without PaA (PaA-free diet) and used as a PaA-deficient group. Group 3 was fed the complete diet, but the daily food amount was equal to the amount of the PaA-deficient group and used as a pair-fed control group. All rats were orally administered 100 mg of L-Trp/kg body weight at 09:00 on day 34 of the experiment and the following 24-h urine samples were collected. The urinary excretion of the sum of pyruvic acid and oxaloacetic acid was higher in rats fed the PaA-free diets than in the rats fed pair-fed the complete diet. PaA deficiency elicited the increased urinary excretion of anthranilic acid and kynurenic acid, while the urinary excretion of xanthurenic acid decreased. The urinary excretion of L-Trp itself, 3-hydroxyanthranilic acid, and quinolinic acid revealed no differences between the rats fed the PaA-free and pair-fed the complete diets. PaA deficiency elicited the increased excretion of N(1)-methylnicotinamide, N(1)-methyl-2-pyridone-5-carboxamide, and N(1)-methyl-4-pyridone-3-carboxamide. These findings suggest that PaA deficiency disturbs the amino acid catabolism.

Polyethylene glycol versus dual sugar assay for gastrointestinal permeability analysis: is it time to choose?

PubMed Central

van Wijck, Kim; Bessems, Babs AFM; van Eijk, Hans MH; Buurman, Wim A; Dejong, Cornelis HC; Lenaerts, Kaatje

2012-01-01

Background Increased intestinal permeability is an important measure of disease activity and prognosis. Currently, many permeability tests are available and no consensus has been reached as to which test is most suitable. The aim of this study was to compare urinary probe excretion and accuracy of a polyethylene glycol (PEG) assay and dual sugar assay in a double-blinded crossover study to evaluate probe excretion and the accuracy of both tests. Methods Gastrointestinal permeability was measured in nine volunteers using PEG 400, PEG 1500, and PEG 3350 or lactulose-rhamnose. On 4 separate days, permeability was analyzed after oral intake of placebo or indomethacin, a drug known to increase intestinal permeability. Plasma intestinal fatty acid binding protein and calprotectin levels were determined to verify compromised intestinal integrity after indomethacin consumption. Urinary samples were collected at baseline, hourly up to 5 hours after probe intake, and between 5 and 24 hours. Urinary excretion of PEG and sugars was determined using high-pressure liquid chromatography-evaporative light scattering detection and liquid chromatography-mass spectrometry, respectively. Results Intake of indomethacin increased plasma intestinal fatty acid-binding protein and calprotectin levels, reflecting loss of intestinal integrity and inflammation. In this state of indomethacin-induced gastrointestinal compromise, urinary excretion of the three PEG probes and lactulose increased compared with placebo. Urinary PEG 400 excretion, the PEG 3350/PEG 400 ratio, and the lactulose/rhamnose ratio could accurately detect indomethacin-induced increases in gastrointestinal permeability, especially within 2 hours of probe intake. Conclusion Hourly urinary excretion and diagnostic accuracy of PEG and sugar probes show high concordance for detection of indomethacin-induced increases in gastrointestinal permeability. This comparative study improves our knowledge of permeability analysis in man by providing a clear overview of both tests and demonstrates equivalent performance in the current setting. PMID:22888267

Excretion of Avenanthramides, Phenolic Acids and their Major Metabolites Following Intake of Oat Bran

PubMed Central

Schär, Manuel Y.; Corona, Giulia; Soycan, Gulten; Dine, Clemence; Kristek, Angelika; Alsharif, Sarah N. S.; Behrends, Volker; Lovegrove, Alison; Shewry, Peter R.

2017-01-01

Scope Wholegrain has been associated with reduced chronic disease mortality, with oat intake particularly notable for lowering blood cholesterol and glycemia. To better understand the complex nutrient profile of oats, we studied urinary excretion of phenolic acids and avenanthramides after ingestion of oat bran in humans. Methods and results After a 2‐d (poly)phenol‐low diet, seven healthy men provided urine 12 h before and 48 h after consuming 60 g oat bran (7.8 μmol avenanthramides, 139.2 μmol phenolic acids) or a phenolic‐low (traces of phenolics) control in a crossover design. Analysis by ultra‐high performance liquid chromatography (UPLC)–MS/MS showed that oat bran intake resulted in an elevation in urinary excretion of 30 phenolics relative to the control, suggesting that they are oat bran‐derived. Mean excretion levels were elevated between 0–2 and 4–8 h, following oat bran intake, and amounted to a total of 33.7 ± 7.3 μmol total excretion (mean recovery: 22.9 ± 5.0%), relative to control. The predominant metabolites included: vanillic acid, 4‐ and 3‐hydroxyhippuric acids, and sulfate‐conjugates of benzoic and ferulic acids, which accounted collectively for two thirds of total excretion. Conclusion Oat bran phenolics follow a relatively rapid urinary excretion, with 30 metabolites excreted within 8 h of intake. These levels of excretion suggest that bound phenolics are, in part, rapidly released by the microbiota. PMID:29024323

Changes of hormones regulating electrolyte metabolism after space flight and hypokinesia

NASA Astrophysics Data System (ADS)

Macho, L.; Fickova, M.; Lichardus, B.; Kvetnansky, R.; Carrey, R. M.; Grigoriev, A.; Popova, I. A.; Tigranian, R. A.; Noskov, V. B.

The changes of hormones in plasma involved in the body fluid regulation were studied in human subjects during and after space flights in relation to redistribution of body fluids in the state of weightlessness. Since hypokinesia was used as a model for simulation of some effects of the stay in microgravity the plasma hormone levels in rats exposed to hypokinesia were also investigated. Plasma aldosterone values showed great individual variations during the first inflight days, the increased levels were observed with prolongation of space flights. The important elevation was found in the recovery period, however it was interesting to note, that in some cosmonauts with repeated exposure to space flight, the postflight plasma aldosterone levels were not elevated. The urine excretion of aldosterone was increased inflight, however in postflight period the decrease or increase were found in the first 1-5 days. The increase of plasma renin activity was observed in flight and postflight period. The rats were exposed to hypokinesia (forced restriction of motor activity) for 1, 7 and 60 days and urine was collected during last 24 hours. The animals were sacrificed and the concentration of electrolytes and of levels of corticosterone aldosteron (A), ANF and plasma-renin activity (PRA) were determined in plasma. In urine excretion of sodium and potassium were estimated. An important increase of plasma renin activity and aldosterone concentration was found after short-term hypokinesia (1 day). These hormonal values appear to decrease with time (7 days) and are not significantly different from controls after long-term hypokinesia (60 days). A decrease of values ANF in plasma was observed after 1 and 7 days hypokinesia. After prolonged hypokinesia a decrease of sodium plasma concentration was observed. The excretion of sodium in urine was higher in long-term hypokinetic animals. There were no significant changes of plasma potassium levels in rats exposed to hypokinesia, however the urinary excretion of potassium was elevated. In rats exposed to hypokinesia for 7 and 60 days an increase of urine osmolality was observed. The results of hormone and electrolyte determination in plasma of cosmonauts after space flight and in experimental animals after hypokinesia suggested that in evaluation of relations between the changes of hormone levels and electrolyte in plasma and urine other factors like emotional stress working load; altered diurnal cycles should be considered in interpretation of homeostatic response of fluid and electrolyte metabolism to space flight conditions.

[Validity of the assessment of urinary protein excretion by spot urine in patients with chronic kidney disease].

PubMed

Hayashi, Ami; Okada, Tomonari; Matsumoto, Hiroshi; Nagaoka, Yume; Wada, Toshikazu; Gondo, Asako; Nango, Tomoka; Miyaoka, Yoshitaka; Watanabe, Kanna; Iwata, Azusa; Nakao, Toshiyuki

2013-01-01

We investigate the validity of the assessment of urinary protein excretion by spot urine samples collected by different methods in outpatients with chronic kidney disease (CKD). SUBJECTS AND METHODS We obtained 24-hour urine and two spot urine samples, including the first morning urine and daytime urine in 159 CKD patients. Urinary protein excretion was assessed by the protein/creatinine ratio from spot urine samples (morning: m-UP (g/gCr), daytime: d-UP (g/gCr) ]. We examined the correlations and the differences among m-UP, d-UP and the actual urinary protein excretion obtained by 24-hour urine (a-UP(g/day) . Significant correlations were found between m-UP and a-UP, and between d-UP and a-UP (r = 0.88, 0.85; p < 0.001). Correlations between m-UP and a-UP were greater relative to those between d-UP and a-UP in patients with less than 3.5 g/day of a-UP and in patients with CKD stages 1 to approximately 3. The percent difference between m-UP and a-UP was--16.0 +/- 40.5%, and that between d-UP and a-UP was 27.1 +/- 72.9%. The absolute value of the percent difference between d-UP and a-UP tended to be greater than that between m-UP and a-UP (34.9 +/- 25.9% vs. 49.9 +/- 59.9%, p = 0.06). Urinary protein/creatinie ratio of the first morning urine is better approximate the urinary protein excretion obtained by 24-hour urine compared with that of spot urine in the daytime.

Urinary free cortisol and cortisone excretion in healthy individuals: influence of water loading.

PubMed

Fenske, Martin

2006-11-01

The influence of water loading on urinary excretion of free cortisol and cortisone was investigated in healthy men. The results were as follows: water loading tests (intake of 0.25-1.5 L) in a single individual showed that a water load of 1.5 L reliably increased the excretion of urine, free cortisol and cortisone (p < 0.01). Regression analyses gave significant correlations of urine volume with free cortisol and free cortisone, and of free cortisol and free cortisone. Corresponding results were obtained when water loading tests were performed in males who ingested 1.5 L of water (n = 8): the excretion of urine, free cortisol and free cortisone were significantly augmented; correlated was urine volume with free cortisol and free cortisone, and free cortisol with free cortisone. In a third set of tests, volunteers collected one 5 h urine (10:00-15:00 h) after the intake of 3 x 0.1 or 0.5 L at 11:00, 12:00 and 14:00 h. Excretion of urine, free cortisol and free cortisone in males of the low water loading group (3 x 0.1 L) was 0.59 mL/min, and 8.2 or 15.0 microg/5 h; corresponding values in individuals ingesting 3 x 0.5 L of water were 1.5 mL/min (p < 0.01), 12.3 microg/5 h (p > 0.05) and 26.3 microg/5 h (p < 0.02). In summary, urinary free cortisol and cortisone excretion in healthy men depends on urine volume, especially during water diuresis. Thus, interpretation of free cortisol and especially of free cortisone excretion is only possible if subjects strictly control their fluid intake and if urine volume is considered an important pre-analytical parameter-otherwise, interpretation of urinary free cortisol results is difficult and of urinary free cortisone data remains tenuous at best.

Influence of genetic susceptibility on the urinary excretion of 8-hydroxydeoxyguanosine of firefighters.

PubMed

Hong, Y C; Park, H S; Ha, E H

2000-06-01

Oxidative DNA damage has been implicated in carcinogenesis. The DNA damage can be assessed from the urinary excretion of the DNA-repair product 8-hydroxydeoxyguanosine (8-OH-dG). The factors were investigated that influenced the excretion of urinary 8-OH-dG in 78 firefighters. 53 Out of 78 firefighters were exposed to fire within 5 days of the study and 25 were not. 8-OH-dG was measured by ELISA and the distribution of the genotypes of CYP1A1, CYP2E1, GSTM1, and GSTT1 was measured by polymerase chain reaction. The homozygous wild type frequencies of CYP1A1 MspI, CYP1A1 ile-val, CYP2E1, GSTM1, and GSTT1 were 31.5%, 56.2%, 60.3%, 50.7%, and 53.4%, respectively. The geometric mean of urinary 8-OH-dG was 14.1 ng/mg creatinine in more active firefighters and 12.3 ng/mg creatinine in non-exposed and less active subjects. Significantly increased concentrations of urinary 8-OH-dG were found to be associated with cigarette smoking, and 14% of the variation of 8-OH-dG was explained by cigarettes smoked per day. The CYP1A1 MspI, CYP1A1 ile-val, GSTM1, and GSTT1 genetic polymorphisms were not found to be significantly associated with the urinary excretion of 8-OH-dG. However, the subjects carrying the CYP2E1 mutant type excreted higher concentrations of 8-OH-dG and there was a marginally significant interaction of GSTT1 with firefighting activity. Multiple regression analysis confirmed that smoking was the strongest predictor of excretion of 8-OH-dG. Age, body mass index, and firefighting activity were not significant predictive factors for urinary 8-OH-dG. Smoking and CYP2E1 gene polymorphism may be important factors in carcinogenesis and the GSTT1 positive genotype may be a genetic susceptibility factor in firefighters who are exposed regularly to various chemical carcinogens.

Increasing plasma [K+] by intravenous potassium infusion reduces NCC phosphorylation and drives kaliuresis and natriuresis.

PubMed

Rengarajan, Srinivas; Lee, Donna H; Oh, Young Taek; Delpire, Eric; Youn, Jang H; McDonough, Alicia A

2014-05-01

Dietary potassium loading results in rapid kaliuresis, natriuresis, and diuresis associated with reduced phosphorylation (p) of the distal tubule Na(+)-Cl(-) cotransporter (NCC). Decreased NCC-p inhibits NCC-mediated Na(+) reabsorption and shifts Na(+) downstream for reabsorption by epithelial Na(+) channels (ENaC), which can drive K(+) secretion. Whether the signal is initiated by ingesting potassium or a rise in plasma K(+) concentration ([K(+)]) is not understood. We tested the hypothesis, in male rats, that an increase in plasma [K(+)] is sufficient to reduce NCC-p and drive kaliuresis. After an overnight fast, a single 3-h 2% potassium (2%K) containing meal increased plasma [K(+)] from 4.0 ± 0.1 to 5.2 ± 0.2 mM; increased urinary K(+), Na(+), and volume excretion; decreased NCC-p by 60%; and marginally reduced cortical Na(+)-K(+)-2Cl(-) cotransporter (NKCC) phosphorylation 25% (P = 0.055). When plasma [K(+)] was increased by tail vein infusion of KCl to 5.5 ± 0.1 mM over 3 h, significant kaliuresis and natriuresis ensued, NCC-p decreased by 60%, and STE20/SPS1-related proline alanine-rich kinase (SPAK) phosphorylation was marginally reduced 35% (P = 0.052). The following were unchanged at 3 h by either the potassium-rich meal or KCl infusion: Na(+)/H(+) exchanger 3 (NHE3), NHE3-p, NKCC, ENaC subunits, and renal outer medullary K(+) channel. In summary, raising plasma [K(+)] by intravenous infusion to a level equivalent to that observed after a single potassium-rich meal triggers renal kaliuretic and natriuretic responses, independent of K(+) ingestion, likely driven by decreased NCC-p and activity sufficient to shift sodium reabsorption downstream to where Na(+) reabsorption and flow drive K(+) secretion.

Effect of Salt Intake and Potassium Supplementation on Serum Renalase Levels in Chinese Adults

PubMed Central

Wang, Yang; Liu, Fu-Qiang; Wang, Dan; Mu, Jian-Jun; Ren, Ke-Yu; Guo, Tong-Shuai; Chu, Chao; Wang, Lan; Geng, Li-Ke; Yuan, Zu-Yi

2014-01-01

Abstract Renalase, a recently discovered enzyme released by the kidneys, breaks down blood-borne catecholamines and may thus regulate blood pressure (BP). Animal studies have suggested that high levels of dietary salt might reduce blood and kidney renalase levels. We conducted a randomized trial to assess the effects of altered salt and potassium intake on serum renalase levels and the relationship between serum renalase levels and BP in humans. Forty-two subjects (28–65 years of age) were selected from a rural community of northern China. All subjects were sequentially maintained on a low-salt diet for 7 days (3.0 g/day of NaCl), a high-salt diet for additional 7 days (18.0 g/day of NaCl), and a high-salt diet with potassium supplementation for final 7 days (18.0 g/day of NaCl + 4.5 g/day of KCl). Serum renalase levels were significantly higher than baseline levels during the low-salt diet intervention period. Renalase levels decreased with the change from the low-salt to high-salt diet, whereas dietary potassium prevented the decrease in serum renalase induced by the high-salt diet. There was a significant inverse correlation between the serum renalase level and 24-h urinary sodium excretion. No significant correlation was found between the renalase level and BP among the different dietary interventions. The present study indicates that variations in dietary salt intake and potassium supplementation affect the serum renalase concentration in Chinese subjects. PMID:25058146

Effect of salt intake and potassium supplementation on serum renalase levels in Chinese adults: a randomized trial.

PubMed

Wang, Yang; Liu, Fu-Qiang; Wang, Dan; Mu, Jian-Jun; Ren, Ke-Yu; Guo, Tong-Shuai; Chu, Chao; Wang, Lan; Geng, Li-Ke; Yuan, Zu-Yi

2014-07-01

Renalase, a recently discovered enzyme released by the kidneys, breaks down blood-borne catecholamines and may thus regulate blood pressure (BP). Animal studies have suggested that high levels of dietary salt might reduce blood and kidney renalase levels. We conducted a randomized trial to assess the effects of altered salt and potassium intake on serum renalase levels and the relationship between serum renalase levels and BP in humans.Forty-two subjects (28-65 years of age) were selected from a rural community of northern China. All subjects were sequentially maintained on a low-salt diet for 7 days (3.0 g/day of NaCl), a high-salt diet for additional 7 days (18.0 g/day of NaCl), and a high-salt diet with potassium supplementation for final 7 days (18.0 g/day of NaCl + 4.5 g/day of KCl).Serum renalase levels were significantly higher than baseline levels during the low-salt diet intervention period. Renalase levels decreased with the change from the low-salt to high-salt diet, whereas dietary potassium prevented the decrease in serum renalase induced by the high-salt diet. There was a significant inverse correlation between the serum renalase level and 24-h urinary sodium excretion. No significant correlation was found between the renalase level and BP among the different dietary interventions.The present study indicates that variations in dietary salt intake and potassium supplementation affect the serum renalase concentration in Chinese subjects.

Differential Diagnosis of Nongap Metabolic Acidosis: Value of a Systematic Approach

PubMed Central

Madias, Nicolaos E.

2012-01-01

Summary Nongap metabolic acidosis is a common form of both acute and chronic metabolic acidosis. Because derangements in renal acid-base regulation are a common cause of nongap metabolic acidosis, studies to evaluate renal acidification often serve as the mainstay of differential diagnosis. However, in many cases, information obtained from the history and physical examination, evaluation of the electrolyte pattern (to determine if a nongap acidosis alone or a combined nongap and high anion gap metabolic acidosis is present), and examination of the serum potassium concentration (to characterize the disorder as hyperkalemic or hypokalemic in nature) is sufficient to make a presumptive diagnosis without more sophisticated studies. If this information proves insufficient, indirect estimates or direct measurement of urinary NH4+ concentration, measurement of urine pH, and assessment of urinary HCO3− excretion can help in establishing the diagnosis. This review summarizes current information concerning the pathophysiology of this electrolyte pattern and the value and limitations of all of the diagnostic studies available. It also provides a systematic and cost-effective approach to the differential diagnosis of nongap metabolic acidosis. PMID:22403272

Circadian rhythm dissociation in an environment with conflicting temporal information

NASA Technical Reports Server (NTRS)

Sulzman, F. M.; Fuller, C. A.; Hiles, L. G.; Moore-Ede, M. C.

1978-01-01

The relative contributions of light-dark (LD) cycles and eating-fasting (EF) cycles in providing temporal information to the circadian time-keeping system were examined in chair-acclimatized squirrel monkeys (Saimiri sciureus). The circadian rhythms of drinking, colonic temperature, urine volume, and urinary potassium excretion were measured with the LD and EF cycles providing either conflicting phases or periods. In conflicting phase experiments, animals were exposed to 24-hr LD cycles consisting of 12 hr of 600 lx followed by 12 hr of less than 1 lx and concurrent 24-hr EF cycles in which the animals ate for 3 hr and then fasted for 21 hr. One group had food available at the beginning and a second group at the end of the light period. In conflicting period experiments, monkeys were exposed to 23-hr LD cycles and 24-hr EF cycles. Analysis of the rhythms showed that both phase and period information were conveyed to the drinking and urinary rhythms by the EF cycle, and to the temperature rhythm by the LD cycle.

Urinary purine derivatives as a tool to estimate dry matter intake in cattle: a meta-analysis

USDA-ARS?s Scientific Manuscript database

The objectives of this study were: 1) to investigate the relationship between dry matter intake (DMI) and urinary purine derivatives (PD) excretion in order to develop equations to predict DMI, and 2) to determine the endogenous excretion of PD for beef and dairy cattle using a meta-analytic approac...

Increased leukotriene E4 excretion in systemic mastocytosis.

PubMed

Butterfield, Joseph H

2010-06-01

Cysteinyl leukotrienes such as LTE(4) are produced by mast cells, neutrophils, eosinophils, and macrophages. LTE(4) levels have not been reported in systemic mastocytosis, a disorder with a large increase in mast cell numbers. Urinary LTE(4) from patients referred for symptoms potentially due to mast cell degranulation or systemic mastocytosis was measured by a commercial cysteinyl leukotriene enzyme immunoassay kit. The diagnosis of systemic mastocytosis was established using current World Health Organization criteria. Compared with a control group of patients with various potential mast cell-related symptoms (e.g., "spells"), patients with systemic mastocytosis had a significant (P=.01) increase in urinary LTE(4) excretion, whether expressed as LTE(4) ng/g creatinine or as LTE(4) ng/24h. There was a moderate correlation of LTE(4) ng/24h with excretion of N-methyl histamine and serum tryptase but not with urinary 11beta-prostaglandin F(2alpha) (11beta-PGF(2alpha)) excretion. LTE(4) excretion is increased in patients with systemic mastocytosis and potentially contributes to clinical symptoms. Copyright 2010 Elsevier Inc. All rights reserved.

Oral salmon calcitonin induced suppression of urinary collagen type II degradation in postmenopausal women: a new potential treatment of osteoarthritis.

PubMed

Bagger, Yu Z; Tankó, László B; Alexandersen, Peter; Karsdal, Morten A; Olson, Melvin; Mindeholm, Linda; Azria, Moïse; Christiansen, Claus

2005-09-01

To assess the efficacy of 3 months of oral salmon calcitonin (sCT) on cartilage degradation as estimated by the changes in the urinary excretion of C-terminal telopeptide of collagen type II (CTX-II), and to investigate whether the response of oral sCT to urinary CTX-II depends on the baseline level of cartilage turnover. This was a randomized, double blind, placebo-controlled clinical setting including 152 Danish postmenopausal women aged 55-85. The subjects received treatment with the different doses of sCT (0.15, 0.4, 1.0, or 2.5 mg) combined with Eligen technology-based carrier molecule (200 mg), or placebo for 3 months. The efficacy parameter was the changes in the 24-h excretion of urinary CTX-I/II corrected for creatinine excretion at month 3. sCT induced a significant dose-dependent decrease in 24-h urinary CTX-II excretion. Similar dose-dependent responses were found in 24-h urinary CTX-I. When stratifying the study population into tertiles of baseline urinary CTX-II, the present osteoarthritic symptoms and definite cases of osteoarthritis (OA) were significantly more frequent in women in the highest tertile of CTX-II (mean 391 +/- 18 ng/mmol). Women who received 1.0 mg of sCT and had the highest cartilage turnover presented the greatest decrease in urinary CTX-II after 3 months of treatment. In addition to its pronounced effect on bone resorption, this novel oral sCT formulation may also reduce cartilage degradation and thereby provide therapeutic benefit in terms of chondroprotection. Women with high cartilage turnover are more likely to benefit from oral sCT treatment.

Ultra-long–term human salt balance studies reveal interrelations between sodium, potassium, and chloride intake and excretion12

PubMed Central

Birukov, Anna; Rakova, Natalia; Lerchl, Kathrin; Engberink, Rik HG Olde; Johannes, Bernd; Wabel, Peter; Moissl, Ulrich; Rauh, Manfred; Luft, Friedrich C; Titze, Jens

2016-01-01

Background: The intake of sodium, chloride, and potassium is considered important to healthy nutrition and cardiovascular disease risk. Estimating the intake of these electrolytes is difficult and usually predicated on urine collections, commonly for 24 h, which are considered the gold standard. We reported on data earlier for sodium but not for potassium or chloride. Objective: We were able to test the value of 24-h urine collections in a unique, ultra-long–term balance study conducted during a simulated trip to Mars. Design: Four healthy men were observed while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, while their potassium intake was maintained at 4 g/d for 105 d. Six healthy men were studied while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, with a re-exposure of 12 g/d, while their potassium intake was maintained at 4 g/d for 205 d. Food intake and other constituents were recorded every day for each subject. All urine output was collected daily. Results: Long-term urine recovery rates for all 3 electrolytes were very high. Rather than the expected constant daily excretion related to daily intake, we observed remarkable daily variation in excretion, with a 7-d infradian rhythm at a relatively constant intake. We monitored 24-h aldosterone excretion in these studies and found that aldosterone appeared to be the regulator for all 3 electrolytes. We report Bland–Altman analyses on the value of urine collections to estimate intake. Conclusions: A single 24-h urine collection cannot predict sodium, potassium, or chloride intake; thus, multiple collections are necessary. This information is important when assessing electrolyte intake in individuals. PMID:27225435

Estimation of the 24-h urinary protein excretion based on the estimated urinary creatinine output.

PubMed

Ubukata, Masamitsu; Takei, Takashi; Nitta, Kosaku

2016-06-01

The urinary protein/creatinine ratio [Up/Ucr (g/gCr)] has been used in the clinical management of patients with chronic kidney disease (CKD). However, a discrepancy is often noted between the Up/Ucr and 24-h urinary protein excretion [24hUp (g/day)] in patients with extremes of muscle mass. We examined devised a method for precise estimation of the 24-h urinary protein excretion (E-24hUp) based on estimation of 24-h urinary creatinine output (E-24hCr). Three parameters, spot Up/Ucr, 24hUP and E-24hUp (=Up/Ucr × E-24hCr), were determined in 116 adult patients with CKD. The correlations among the groups were analyzed. There was a significant correlation between the Up/Ucr and 24hUp (p < 0.001). We divided the patients into three groups according to the 24hUp; the low urinary protein group (<1.0 g/day), the intermediate urinary protein group (1.0-3.5 g/day), and the high urinary protein group (>3.5 g/day). There was a significant correlation between the Up/Ucr and 24hUp in the low (p = 0.04) and high urinary protein (p = 0.01) groups, whereas the correlation coefficient was lower in the intermediate urinary protein (p = 0.07) group. Thus, we found a significant correlation between 24hUp and E-24hUp in the study population overall (p < 0.001), in the low (p = 0.01), in the intermediate (p < 0.001), and in the high urinary protein group (p < 0.001). We conclude that a poor correlation exists between the Up/Ucr and 24hUp in patients with intermediate urinary protein excretion levels. The recommended parameter for monitoring proteinuria in such patients may be the E-24hUp, which is calculated using the E-24hCr.

Self-reports of salt intake by 10- to 18-year-olds: relationship to urinary sodium excretion.

PubMed

Murphy, J K; Alpert, B S; Stapleton, F B; Miller, L A; Willey, E S; Walker, S S; Nanney, G C

1990-03-01

Our data indicated that self-reports of consumption of salty foods by children and adolescents were associated with 24-hour urinary sodium excretion. Specifically, youths 10 to 18 years of age who selected a poster depicting high-sodium foods excreted significantly more sodium than youths who selected a poster depicting low-sodium foods. Future research is needed to refine simplified self-report measures, to corroborate the validity of the measures, and to extend the studies to other samples, e.g., younger children.

The renal TRPV4 channel is essential for adaptation to increased dietary potassium.

PubMed

Mamenko, Mykola V; Boukelmoune, Nabila; Tomilin, Viktor N; Zaika, Oleg L; Jensen, V Behrana; O'Neil, Roger G; Pochynyuk, Oleh M

2017-06-01

To maintain potassium homeostasis, kidneys exert flow-dependent potassium secretion to facilitate kaliuresis in response to elevated dietary potassium intake. This process involves stimulation of calcium-activated large conductance maxi-K (BK) channels in the distal nephron, namely the connecting tubule and the collecting duct. Recent evidence suggests that the TRPV4 channel is a critical determinant of flow-dependent intracellular calcium elevations in these segments of the renal tubule. Here, we demonstrate that elevated dietary potassium intake (five percent potassium) increases renal TRPV4 mRNA and protein levels in an aldosterone-dependent manner and causes redistribution of the channel to the apical plasma membrane in native collecting duct cells. This, in turn, leads to augmented TRPV4-mediated flow-dependent calcium ion responses in freshly isolated split-opened collecting ducts from mice fed the high potassium diet. Genetic TRPV4 ablation greatly diminished BK channel activity in collecting duct cells pointing to a reduced capacity to excrete potassium. Consistently, elevated potassium intake induced hyperkalemia in TRPV4 knockout mice due to deficient renal potassium excretion. Thus, regulation of TRPV4 activity in the distal nephron by dietary potassium is an indispensable component of whole body potassium balance. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Effect of losartan on proteinuria and urinary angiotensinogen excretion in non-diabetic patients with chronic kidney disease.

PubMed

Lee, Yu-Ji; Cho, Seong; Kim, Sung Rok; Jang, Hye Ryoun; Lee, Jung Eun; Huh, Wooseong; Kim, Dae Joong; Oh, Ha Young; Kim, Yoon-Goo

2011-10-01

Activation of the rennin-angiotensin system (RAS) is thought to contribute to hypertension and proteinuria, and eventually to the progression of chronic kidney disease (CKD). Recent evidence suggests that urinary angiotensinogen (UAGT) excretion reflects activation of the intrarenal RAS. This study was performed to determine the effect of losartan on proteinuria and UAGT excretion in non-diabetic patients with CKD with non-nephrotic-range proteinuria. Thirty-two patients with non-nephrotic-range proteinuria (0.045-0.23 g/mmol creatinine) and normal renal function between April 2005 and April 2006 were randomised to a losartan (n=17) or a control (n=15) group. Patients in the losartan group received losartan 50 mg/day, and the doses were titrated up to 100 mg/day after 6 weeks. Serum and urinary angiotensinogen concentrations were measured by sandwich ELISA. The primary end point was the percentage change in proteinuria. The secondary end points were changes in estimated glomerular filtration rate and UAGT excretion. The follow-up period was 24 months. Baseline characteristics in the two groups were similar. After 24 months, losartan had reduced urinary protein excretion by 43% (from mean±SD 0.13±0.04 to 0.073±0.03 g/mmol, p<0.0001), but proteinuria had not changed in the control group. The percentage change in mean arterial pressure did not differ between the groups. Losartan decreased logarithmically converted UAGT excretion (from 1.58±0.47 to 1.00±0.52, p=0.001). Estimated glomerular filtration rate decreased significantly only in the control group. Losartan significantly decreased proteinuria and UAGT excretion, and preserved renal function in non-diabetic patients with CKD.

Lime powder treatment reduces urinary excretion of total protein and transferrin but increases uromodulin excretion in patients with urolithiasis.

PubMed

Tosukhowong, Piyaratana; Kulpradit, Pimsuda; Chaiyarit, Sakdithep; Ungjareonwattana, Wattanachai; Kalpongnukul, Nuttiya; Ratchanon, Supoj; Thongboonkerd, Visith

2018-06-01

Our previous study has shown that lime powder (LP) had an inhibitory effect against calcium oxalate stone formation. However, the precise mechanisms underlying such beneficial effect remained unclear. Our present study thus aimed to address the effect of LP on excretory level and compositions of urinary proteins using a proteomics approach. From a total of 80 calcium oxalate stone formers recruited into our 2-year randomized clinical trial of LP effect, 10 patients with comparable age and clinical parameters were selected for this proteomic study. 24-h urine specimens were collected from all subjects, at baseline (before) and after LP treatment for 6 months, and then subjected to quantitative proteomics analysis and subsequent validation by ELISA. Total urinary protein excretion was significantly decreased by LP treatment, but unaffected by placebo. Nanoflow liquid chromatography coupled to tandem mass spectrometry (nanoLC-MS/MS) followed by quantitative analysis revealed 17 proteins whose levels were significantly altered (16 decreased and 1 increased) exclusively by LP treatment. Among these, the decrease of transferrin and increase of uromodulin were validated by ELISA. Moreover, there was a significant correlation between microalbuminuria and urinary transferrin level by Pearson's correlation test. In summary, LP treatment caused significant reduction in total urinary protein excretion and changes in urinary protein compositions that could be linked to stone inhibitory effects and might be relevant mechanisms responsible for the beneficial effects of LP to prevent kidney stone formation and recurrence.

[Renal handling of beta2 microglobulin. Its significance in carriers of adolescent nephronophthisis (NPH3)].

PubMed

Fernández, Carmen; Araque, Carolina; Méndez, Jorge; Angulo, Luisa; Fargier, Bernardo

2007-06-01

The adolescent nephronophthisis (NPH3) is a variant of the nephronophthisis. In Venezuela, one to three patients have been registered each year, all of them belonging to the same family tree. The objective of this study was to evaluate the function of the proximal convoluted tubule in NPHP3 carriers; using the beta2M as biological marker. Eight carriers, 7 heterozygotes and 1 homozygote, with normal renal function were compared with a 10 healthy subjects (control group). Serum beta2 microglobulin (beta2M), urinary beta2M, the quotient urinary beta2M/urinary creatinine and the beta2M fractional excretion were determinated. The filtered beta2M and the percentage of reabsortion were calculated. We observed an increase in the plasmatic concentration of beta2M but not related with a decrease of the glomerular filtration. The urinary beta2M, the beta2M/urinary creatinine relation and the fractional excretion of beta2M were normal. The filtered load of beta2M was elevated without increase in the excretion or percentage of reabsortion. We conclude that in our group of NPH3 carriers, functional changes in the proximal convoluted tubule, when measured by urinary excretion of beta2M, were absent. This finding suggests the existence of other mechanism of uptake or degradation of the substance in the proximal convoluted tubule, which have yet to be elucidated.

Effects of drugs which influence renal transport systems on the urinary excretion of the beta 2-adrenoceptor agonist clenbuterol and the anabolic steroids ethinylestradiol and methyltestosterone.

PubMed

Gleixner, A; Sauerwein, H; Meyer, H H

1997-01-01

The aim of this study was to determine whether the illegal application of clenbuterol, ethinylestradiol and methyltestosterone in cattle as growth promoters can be concealed by co-treatment with drugs that affect urinary excretion. Six male veal calves were fed with 0.8 micrograms clenbuterol kg-1 of body weight (BW), 3.5 micrograms ethinylestradiol kg-1 BW and 35 micrograms methyltestosterone kg-1 BW together twice daily for 28 days. At the eighth day of clenbuterol, ethinylestradiol and methyltestosterone treatment each calf was additionally fed either with probenecid, para-aminohippuric acid, trimethoprim, famotidine or cimetidine at three different doses which were increased in weekly intervals. During the treatment 24 h-urine and blood samples (once daily) were obtained and analysed for clenbuterol, ethinylestradiol and methyltestosterone by specific enzyme immunoassay. By high performance liquid chromatography/enzyme immunoassay it was determined whether these drugs or their metabolites interfered with the immunological detection of the growth promoters. Clenbuterol, ethinylestradiol and methyltestosterone could be detected in plasma and urine throughout the whole experiment. Co-treatment with probenecid led to a five-fold reduction in urinary excretion of ethinylestradiol and co-treatment with trimethoprim led to a three-fold reduction in urinary excretion of clenbuterol. None of the drugs reduced urinary excretion of the growth promoters to concentrations below the limit of detection. The detection of these three growth promoters in urine samples from calves which were co-treated with the drugs tested in this study can thus not be prevented.

Amino Acid Medical Foods Provide a High Dietary Acid Load and Increase Urinary Excretion of Renal Net Acid, Calcium, and Magnesium Compared with Glycomacropeptide Medical Foods in Phenylketonuria

PubMed Central

Stroup, Bridget M.; Sawin, Emily A.; Murali, Sangita G.; Binkley, Neil; Hansen, Karen E.

2017-01-01

Background. Skeletal fragility is a complication of phenylketonuria (PKU). A diet containing amino acids compared with glycomacropeptide reduces bone size and strength in mice. Objective. We tested the hypothesis that amino acid medical foods (AA-MF) provide a high dietary acid load, subsequently increasing urinary excretion of renal net acid, calcium, and magnesium, compared to glycomacropeptide medical foods (GMP-MF). Design. In a crossover design, 8 participants with PKU (16–35 y) provided food records and 24-hr urine samples after consuming a low-Phe diet in combination with AA-MF and GMP-MF for 1–3 wks. We calculated potential renal acid load (PRAL) of AA-MF and GMP-MF and determined bone mineral density (BMD) measurements using dual X-ray absorptiometry. Results. AA-MF provided 1.5–2.5-fold higher PRAL and resulted in 3-fold greater renal net acid excretion compared to GMP-MF (p = 0.002). Dietary protein, calcium, and magnesium intake were similar. GMP-MF significantly reduced urinary excretion of calcium by 40% (p = 0.012) and magnesium by 30% (p = 0.029). Two participants had low BMD-for-age and trabecular bone scores, indicating microarchitectural degradation. Urinary calcium with AA-MF negatively correlated with L1–L4 BMD. Conclusion. Compared to GMP-MF, AA-MF increase dietary acid load, subsequently increasing urinary calcium and magnesium excretion, and likely contributing to skeletal fragility in PKU. The trial was registered at clinicaltrials.gov as NCT01428258. PMID:28546877

Urinary excretion of ciprofloxacin after administration of extended release tablets in healthy volunteers. Swellable drug-polyelectrolyte matrix versus bilayer tablets.

PubMed

Guzmán, M L; Romañuk, C B; Sanchez, M F; Luciani Giacobbe, L C; Alarcón-Ramirez, L P; Battistini, F D; Alovero, F L; Jimenez-Kairuz, A F; Manzo, R H; Olivera, María Eugenia

2018-02-01

This paper builds on a previous paper in which new ciprofloxacin extended-release tablets were developed based on a ciprofloxacin-based swellable drug polyelectrolyte matrix (SDPM-CIP). The matrix contains a molecular dispersion of ciprofloxacin ionically bonded to the acidic groups of carbomer, forming the polyelectrolyte-drug complex CB-CIP. This formulation showed that the release profile of the ciprofloxacin bilayer tablets currently commercialised can be achieved with a simpler strategy. Thus, since ciprofloxacin urine concentrations are associated with the clinical cure of urinary tract infections, the goal of this work was to compare the urinary excretion of SDPM-CIP tablets with those of the CIPRO XR® bilayer tablets. A batch of SDPM-CIP tablets was manufactured by the wet granulation method and the CB-CIP ionic complex was obtained in situ. Fasted healthy volunteers received a single oral dose of 500 mg ciprofloxacin of either formulation in a randomised crossover study. Urinary concentrations were assessed by HPLC at intervals up to 36 h. Pharmacokinetic parameters (rate of urinary excretion, maximum urine excretion rate, t max , area under the curve, amount and percentage of the ciprofloxacin dose excreted in urine) showed no statistical differences between both formulations at any of the time intervals of collection. The processing conditions to obtain SDPM-CIP tablets are easy to scale up since they involve technology currently employed in the pharmaceutical industry and the process is less challenging to implement. In addition, SDPM-CIP tablets met pharmacopoeial quality specifications.

Dietary Sodium Restriction and Association with Urinary Marinobufagenin, Blood Pressure, and Aortic Stiffness

PubMed Central

Fedorova, Olga V.; Racine, Matthew L.; Geolfos, Candace J.; Gates, Phillip E.; Chonchol, Michel; Fleenor, Bradley S.; Lakatta, Edward G.; Bagrov, Alexei Y.; Seals, Douglas R.

2013-01-01

Summary Background and objectives Systolic BP and large elastic artery stiffness both increase with age and are reduced by dietary sodium restriction. Production of the natriuretic hormone marinobufagenin, an endogenous α1 Na+,K+-ATPase inhibitor, is increased in salt-sensitive hypertension and contributes to the rise in systolic BP during sodium loading. Design, setting, participants, & measurements The hypothesis was that dietary sodium restriction performed in middle-aged/older adults (eight men and three women; 60±2 years) with moderately elevated systolic BP (139±2/83±2 mmHg) would reduce urinary marinobufagenin excretion as well as systolic BP and aortic pulse-wave velocity (randomized, placebo-controlled, and crossover design). This study also explored the associations among marinobufagenin excretion with systolic BP and aortic pulse-wave velocity across conditions of 5 weeks of a low-sodium (77±9 mmol/d) and 5 weeks of a normal-sodium (144±7 mmol/d) diet. Results Urinary marinobufagenin excretion (weekly measurements; 25.4±1.8 versus 30.7±2.1 pmol/kg per day), systolic BP (127±3 versus 138±5 mmHg), and aortic pulse-wave velocity (700±40 versus 843±36 cm/s) were lower during the low- versus normal-sodium condition (all P<0.05). Across all weeks, marinobufagenin excretion was related with systolic BP (slope=0.61, P<0.001) and sodium excretion (slope=0.46, P<0.001). These associations persisted during the normal- but not the low-sodium condition (both P<0.005). Marinobufagenin excretion also was associated with aortic pulse-wave velocity (slope=0.70, P=0.02) and endothelial cell expression of NAD(P)H oxidase-p47phox (slope=0.64, P=0.006). Conclusions These results show, for the first time in humans, that dietary sodium restriction reduces urinary marinobufagenin excretion and that urinary marinobufagenin excretion is positively associated with systolic BP, aortic stiffness (aortic pulse-wave velocity), and endothelial cell expression of the oxidant enzyme NAD(P)H oxidase. Importantly, marinobufagenin excretion is positively related to systolic BP over ranges of sodium intake typical of an American diet, extending previous observations in rodents and humans fed experimentally high-sodium diets. PMID:23929930

Mathematical Model of Ammonia Handling in the Rat Renal Medulla

PubMed Central

Noiret, Lorette; Baigent, Stephen; Jalan, Rajiv; Thomas, S. Randall

2015-01-01

The kidney is one of the main organs that produces ammonia and release it into the circulation. Under normal conditions, between 30 and 50% of the ammonia produced in the kidney is excreted in the urine, the rest being absorbed into the systemic circulation via the renal vein. In acidosis and in some pathological conditions, the proportion of urinary excretion can increase to 70% of the ammonia produced in the kidney. Mechanisms regulating the balance between urinary excretion and renal vein release are not fully understood. We developed a mathematical model that reflects current thinking about renal ammonia handling in order to investigate the role of each tubular segment and identify some of the components which might control this balance. The model treats the movements of water, sodium chloride, urea, NH3 and NH4+, and non-reabsorbable solute in an idealized renal medulla of the rat at steady state. A parameter study was performed to identify the transport parameters and microenvironmental conditions that most affect the rate of urinary ammonia excretion. Our results suggest that urinary ammonia excretion is mainly determined by those parameters that affect ammonia recycling in the loops of Henle. In particular, our results suggest a critical role for interstitial pH in the outer medulla and for luminal pH along the inner medullary collecting ducts. PMID:26280830

The arginine-creatine pathway is disturbed in children and adolescents with renal transplants.

PubMed

Andrade, Fernando; Rodríguez-Soriano, Juan; Prieto, José Angel; Elorz, Javier; Aguirre, Mireia; Ariceta, Gema; Martin, Sergio; Sanjurjo, Pablo; Aldámiz-Echevarría, Luis

2008-08-01

Cardiovascular disease is an important cause of morbidity in recipients of renal transplants. The aim of the present study was to analyze the status of the arginine-creatine pathway in such patients, given the relationship between the arginine metabolism and both renal function and the methionine-homocysteine cycle. Twenty-nine children and adolescents (median age 13, range 6-18 years), who had received a renal allograft 14.5-82.0 months before, were recruited for the study. On immunosuppressive therapy, all patients evidenced an adequate level of renal function. Plasma concentrations of homocysteine and glycine were significantly higher, whereas urinary excretions of guanidinoacetate and creatine were significantly lower than controls. Urinary excretions of guanidinoacetate and creatine correlated positively with creatinine clearance. Urinary excretion of creatine was negatively correlated with plasma concentration of homocysteine. The demonstration of disturbances in the arginine-creatine pathway in patients with well-functioning renal transplants and in absence of chronic renal failure represents a novel finding. We speculate that the low urinary excretion of guanidinoacetate and creatine is probably related to the nephrotoxic effect of immunosuppressive therapy and to defective methylation associated with the presence of hyperhomocysteinemia.

[Effects of excess pyridoxine-HCl on growth and urinary excretion of water-soluble vitamins in weaning rats].

PubMed

Fukuwatari, Tsutomu; Itoh, Keiko; Shibata, Katsumi

2009-04-01

To determine the tolerable upper intake level of pyridoxine-HCl in humans, we investigated the effects of excess pyridoxine-HCl administration on body weight gain, food intake, tissue weight, and urinary excretion of water-soluble vitamins in weaning rats. The weaning rats were freely fed ordinary diet containing 0.0007% pyridoxine-HCl (control diet) or the same diet with 0.1%, 0.5%, 0.8% or 1.0% pyridoxine-HCl for 30 days. The body weight gain in the 0.8% and 1.0% groups, and the total food intake in the 1.0% group were significantly lower than those in the control group. The urinary excretion of pantothenic acid in the pyridoxine-HCl added groups were higher than that in the control group, while excessive pyridoxine-HCl intake did not affect the urinary excretion of other water-soluble vitamins. These results showed that the no-observed-adverse-effect-level (NOAEL) for pyridoxine-HCl was 0.1% in diet, corresponding to 90 mg/kg body weight/day, and lowest-observed-adverse-effect-level (LOAEL) was 0.5% in diet, corresponding to 450 mg/kg body weight/day.

Comparison of plutonium systemic distribution in rats and dogs with published data in humans.

PubMed

Melo, Dunstana R; Weber, Waylon; Doyle-Eisele, Melanie; Guilmette, Raymond A

2014-11-01

This manuscript compares the behavior of monomeric (239)Pu(4+)-citrate injected intravenously in rats and dogs with a comparison of available humans' data. The experimental design for these two studies consisted of eight groups sacrificed at predetermined time-points post exposure. All organs and tissues as well as daily urinary and fecal excretion were analyzed. Liver and skeleton were the organs with the highest (239)Pu uptake in both species; 76% in dogs and 70% in rats at 24 hours (h) post IV administration. By the end of the study (28 days, d), the activity in skeleton and liver was 85% in dogs and 65% in rats. The urinary excretion function seems to be similar for rats, dogs and humans but the daily fecal to urinary excretion ratio differs between species. A rapid clearance from the liver of rats was observed compared to dogs. Skeleton-to-liver ratios are variable between species. Urinary and fecal excretion patterns for dogs are consistent with human data, indicating that dogs seem to represent better the (239)Pu behavior in humans. The data confirm that the better animal model to evaluate the efficacy of (239)Pu chelating compounds is the canine model.

Effect of urinary trypsin inhibitor on potassium currents: fetus modulates membrane excitability by production of UTI.

PubMed

Takeuchi, Kinya; Fukuda, Atsuo; Kanayama, Naohiro

2004-01-01

Amniotic fluid contains a significant level of urinary trypsin inhibitor (UTI). Previously, we reported that UTI inhibits calcium influx of myometrium and it is effective in preventing uterine contraction. This study examined the effects of UTI upon potassium channels, which is important for membrane excitability. Whole-cell patch-clamp recordings were performed in fibroblasts derived from human fetal skin. Potassium currents were recorded and the effects of exogenous UTI and/or cadmium determined. Tetraethylammonium sensitive potassium currents were elicited by step or ramp stimulations at depolarized membrane potentials (over +30 mV). Administration of 1 micro M UTI significantly increased these potassium currents by 16.9%. When calcium channels were blocked by the administration of cadmium, UTI increased the rest of the potassium currents by 4.8%. This indicates that UTI increased calcium-dependent potassium currents by 94.8% but only increased voltage-dependent potassium currents by 4.8%. Urinary trypsin inhibitor is a physiological substance of fetal origin that modulates calcium-dependent and voltage-dependent potassium channels. These data suggest that UTI is capable of regulating the membrane properties of the fetal and myometrial cells in contact with amniotic fluid.

The fractional urinary fluoride excretion of adults consuming naturally and artificially fluoridated water and the influence of water hardness: a randomized trial.

PubMed

Villa, A; Cabezas, L; Anabalón, M; Rugg-Gunn, A

2009-09-01

To assess whether there was any significant difference in the average fractional urinary fluoride excretion (FUFE) values among adults consuming (NaF) fluoridated Ca-free water (reference water), naturally fluoridated hard water and an artificially (H2SiF6) fluoridated soft water. Sixty adult females (N=20 for each treatment) participated in this randomized, double-blind trial. The experimental design of this study provided an indirect estimation of the fluoride absorption in different types of water through the assessment of the fractional urinary fluoride excretion of volunteers. Average daily FUFE values (daily amount of fluoride excreted in urine/daily total fluoride intake) were not significantly different between the three treatments (Kruskal-Wallis; p = 0.62). The average 24-hour FUFE value (n=60) was 0.69; 95% C.I. 0.65-0.73. The results of this study suggest that the absorption of fluoride is not affected by water hardness.

Can lemon juice be an alternative to potassium citrate in the treatment of urinary calcium stones in patients with hypocitraturia? A prospective randomized study.

PubMed

Aras, Bekir; Kalfazade, Nadir; Tuğcu, Volkan; Kemahli, Eray; Ozbay, Bedi; Polat, Hakan; Taşçi, Ali Ihsan

2008-12-01

To investigate that lemon juice could be an alternative to potassium citrate in the treatment of urinary calcium stones in patients with hypocitraturia, 30 patients with hypocitraturic urinary calcium stones were enrolled into study. The patients were divided into three groups equally. Exactly 60 mEq/day fresh lemon juice ( approximately 85 cc/day) and potassium citrate (60 mEq/day) were given to the patients of first and second group, respectively. Dietary recommendations were made for the third group. Blood and 24-h urine tests were performed before treatment and repeated 3 months later. The differences between demographic datas of groups were not significant. There was no significant difference between values of blood tests performed before and after treatment in all groups. Statistically significant differences were found between pre- and post-treatment urine values in each group. Although there was no significant difference between pre-treatment citrate levels of the groups. A significant difference was found between post-treatment citrate levels of the groups. There was 2.5-, 3.5- and 0.8-fold increase in urinary citrate level of lemon juice, potassium citrate and dietary recommendation groups, respectively. Urinary calcium level was decreased only in lemon juice and potassium citrate groups after treatment. While there was no significant difference between pre- and post-treatment urinary oxalate levels in all groups, a significant decrease in urinary uric acid levels was determined in all groups. We suggest that lemon juice can be an alternative in the treatment of urinary calcium stones in patients with hypocitraturia. Additionally, dietary recommendations can increase effectiveness of the treatment.

Prediction of urinary nitrogen and urinary urea nitrogen excretion by lactating dairy cattle in northwestern Europe and North America: a meta-analysis.

PubMed

Spek, J W; Dijkstra, J; van Duinkerken, G; Hendriks, W H; Bannink, A

2013-07-01

A meta-analysis was conducted on the effect of dietary and animal factors on the excretion of total urinary nitrogen (UN) and urinary urea nitrogen (UUN) in lactating dairy cattle in North America (NA) and northwestern Europe (EU). Mean treatment data were used from 47 trials carried out in NA and EU. Mixed model analysis was used with experiment included as a random effect and all other factors, consisting of dietary and animal characteristics, included as fixed effects. Fixed factors were nested within continent (EU or NA). A distinction was made between urinary excretions based on either urine spot samples or calculated assuming a zero N balance, and excretions that were determined by total collection of urine only. Moreover, with the subset of data based on total collection of urine, a new data set was created by calculating urinary N excretion assuming a zero N balance. Comparison with the original subset of data allowed for examining the effect of such an assumption on the relationship established between milk urea N (MUN) concentration and UN. Of all single dietary and animal factors evaluated to predict N excretion in urine, MUN and dietary crude protein (CP) concentration were by far the best predictors. Urinary N excretion was best predicted by the combination of MUN, CP, and dry matter intake, whereas UUN was best predicted by the combination of MUN and CP. All other factors did not improve or only marginally improved the prediction of UN or UUN. The relationship between UN and MUN differed between NA and EU, with higher estimated regression coefficients for MUN for the NA data set. Precision of UN and UUN prediction improved substantially when only UN or UUN data based on total collection of urine were used. The relationship between UN and MUN for the NA data set, but not for the EU data set, was substantially altered when UN was calculated assuming a zero N balance instead of being based on the total collection of urine. According to results of the present meta-analysis, UN and UUN are best predicted by the combination of MUN and CP and that, in regard to precision and accuracy, prediction equations for UN and UUN should be derived from the total collection of urine. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Diet effects on urine composition of cattle and N2O emissions.

PubMed

Dijkstra, J; Oenema, O; van Groenigen, J W; Spek, J W; van Vuuren, A M; Bannink, A

2013-06-01

Ruminant production contributes to emissions of nitrogen (N) to the environment, principally ammonia (NH3), nitrous oxide (N2O) and di-nitrogen (N2) to air, nitrate (NO3 -) to groundwater and particulate N to surface waters. Variation in dietary N intake will particularly affect excretion of urinary N, which is much more vulnerable to losses than is faecal N. Our objective is to review dietary effects on the level and form of N excreted in cattle urine, as well as its consequences for emissions of N2O. The quantity of N excreted in urine varies widely. Urinary N excretion, in particular that of urea N, is decreased upon reduction of dietary N intake or an increase in the supply of energy to the rumen microorganisms and to the host animal itself. Most of the N in urine (from 50% to well over 90%) is present in the form of urea. Other nitrogenous components include purine derivatives (PD), hippuric acid, creatine and creatinine. Excretion of PD is related to rumen microbial protein synthesis, and that of hippuric acid to dietary concentration of degradable phenolic acids. The N concentration of cattle urine ranges from 3 to 20 g/l. High-dietary mineral levels increase urine volume and lead to reduced urinary N concentration as well as reduced urea concentration in plasma and milk. In lactating dairy cattle, variation in urine volume affects the relationship between milk urea and urinary N excretion, which hampers the use of milk urea as an accurate indicator of urinary N excretion. Following its deposition in pastures or in animal houses, ubiquitous microorganisms in soil and waters transform urinary N components into ammonium (NH4 +), and thereafter into NO3 - and ultimately in N2 accompanied with the release of N2O. Urinary hippuric acid, creatine and creatinine decompose more slowly than urea. Hippuric acid may act as a natural inhibitor of N2O emissions, but inhibition conditions have not been defined properly yet. Environmental and soil conditions at the site of urine deposition or manure application strongly influence N2O release. Major dietary strategies to mitigating N2O emission from cattle operations include reducing dietary N content or increasing energy content, and increasing dietary mineral content to increase urine volume. For further reduction of N2O emission, an integrated animal nutrition and excreta management approach is required.

Sodium and potassium content of 24 h urinary collections: a comparison between field- and laboratory-based analysers.

PubMed

Yin, Xuejun; Neal, Bruce; Tian, Maoyi; Li, Zhifang; Petersen, Kristina; Komatsu, Yuichiro; Feng, Xiangxian; Wu, Yangfeng

2018-04-01

Measurement of mean population Na and K intakes typically uses laboratory-based assays, which can add significant logistical burden and costs. A valid field-based measurement method would be a significant advance. In the current study, we used 24 h urine samples to compare estimates of Na, K and Na:K ratio based upon assays done using the field-based Horiba twin meter v. laboratory-based methods. The performance of the Horiba twin meter was determined by comparing field-based estimates of mean Na and K against those obtained using laboratory-based methods. The reported 95 % limits of agreement of Bland-Altman plots were calculated based on a regression approach for non-uniform differences. The 24 h urine samples were collected as part of an ongoing study being done in rural China. One hundred and sixty-six complete 24 h urine samples were qualified for estimating 24 h urinary Na and K excretion. Mean Na and K excretion were estimated as 170·4 and 37·4 mmol/d, respectively, using the meter-based assays; and 193·4 and 43·8 mmol/d, respectively, using the laboratory-based assays. There was excellent relative reliability (intraclass correlation coefficient) for both Na (0·986) and K (0·986). Bland-Altman plots showed moderate-to-good agreement between the two methods. Na and K intake estimations were moderately underestimated using assays based upon the Horiba twin meter. Compared with standard laboratory-based methods, the portable device was more practical and convenient.

Urinary type IV collagen excretion predicts subsequent declining renal function in type 2 diabetic patients with proteinuria.

PubMed

Katavetin, Pisut; Katavetin, Paravee; Susantitaphong, Paweena; Townamchai, Natavudh; Tiranathanagul, Khajohn; Tungsanga, Kriang; Eiam-Ong, Somchai

2010-08-01

Baseline urinary type IV collagen excretion was negatively correlated with the subsequent GFR change (r(s)=-0.39, p=0.04) in our cohort of 30 type 2 diabetic patients with proteinuria. Therefore, it could be used to predict subsequent declining renal function in type 2 diabetic patients with proteinuria. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

COMPARATIVE TISSUE DISTRIBUTION AND URINARY EXCRETION OF INORGANIC ARSENIC (IAS) AND ITS METHYLATED METABOLITES IN MICE FOLLOWING ORAL ADMINISTRATION OF ARSENATE (ASV) AND ARSENITE (ASIII)

EPA Science Inventory

COMPARATIVE TISSUE DISTRIBUTION AND URINARY EXCRETION OF INORGANIC ARSENIC (iAs) AND ITS METHYLATED METABOLITES IN MICE FOLLOWING ORAL ADMINISTRATION OF ARSENATE (AsV) AND ARSENITE (AsIII). E M Kenyon, L M Del Razo and M F Hughes. U.S. EPA, ORD, NHEERL, ETD, PKB, RTP, NC, USA; ...

Urinary prostaglandin excretion in pregnancy: the effect of dietary sodium restriction.

PubMed

Delemarre, F M; Thomas, C M; van den Berg, R J; Jongsma, H W; Steegers, E A

2000-10-01

Dietary sodium restriction results in activation of the renin-angiotensin-aldosterone-system. In the non-pregnant situation renin release in response to a low sodium diet is mediated by prostaglandins. We studied the effect of dietary sodium restriction on urinary prostaglandin metabolism in pregnancy. In a randomized, longitudinal study the excretion of urinary metabolites of prostacyclin (6-keto-PGF(1 alpha)and 2,3-dinor-6-keto-PGF(1 alpha)) and thromboxane A(2)(TxB(2)and 2,3-dinor-TxB(2)) was determined throughout pregnancy and post partum in 12 women on a low sodium diet and in 12 controls. In pregnancy the excretion of all urinary prostaglandins is increased. The 6-keto-PGF(1 alpha)/ TxB(2)-ratio as well as the 2, 3-dinor-6-keto-PGF(1 alpha)/ 2,3-dinor-TxB(2)-ratio did not significantly change in pregnancy. CONCLUISION Prostacyclin and thromboxane do not seem to play an important role in sodium balance during pregnancy. Copyright 2000 Harcourt Publishers Ltd.

Dramatic elevation in urinary amino terminal titin fragment excretion quantified by immunoassay in Duchenne muscular dystrophy patients and in dystrophin deficient rodents.

PubMed

Robertson, Alan S; Majchrzak, Mark J; Smith, Courtney M; Gagnon, Robert C; Devidze, Nino; Banks, Glen B; Little, Sean C; Nabbie, Fizal; Bounous, Denise I; DiPiero, Janet; Jacobsen, Leslie K; Bristow, Linda J; Ahlijanian, Michael K; Stimpson, Stephen A

2017-07-01

Enzyme-linked and electrochemiluminescence immunoassays were developed for quantification of amino (N-) terminal fragments of the skeletal muscle protein titin (N-ter titin) and qualified for use in detection of urinary N-ter titin excretion. Urine from normal subjects contained a small but measurable level of N-ter titin (1.0 ± 0.4 ng/ml). A 365-fold increase (365.4 ± 65.0, P = 0.0001) in urinary N-ter titin excretion was seen in Duchene muscular dystrophy (DMD) patients. Urinary N-ter titin was also evaluated in dystrophin deficient rodent models. Mdx mice exhibited low urinary N-ter titin levels at 2 weeks of age followed by a robust and sustained elevation starting at 3 weeks of age, coincident with the development of systemic skeletal muscle damage in this model; fold elevation could not be determined because urinary N-ter titin was not detected in age-matched wild type mice. Levels of serum creatine kinase and serum skeletal muscle troponin I (TnI) were also low at 2 weeks, elevated at later time points and were significantly correlated with urinary N-ter titin excretion in mdx mice. Corticosteroid treatment of mdx mice resulted in improved exercise performance and lowering of both urinary N-ter titin and serum skeletal muscle TnI concentrations. Low urinary N-ter titin levels were detected in wild type rats (3.0 ± 0.6 ng/ml), while Dmd mdx rats exhibited a 556-fold increase (1652.5 ± 405.7 ng/ml, P = 0.002) (both at 5 months of age). These results suggest that urinary N-ter titin is present at low basal concentrations in normal urine and increases dramatically coincident with muscle damage produced by dystrophin deficiency. Urinary N-ter titin has potential as a facile, non-invasive and translational biomarker for DMD. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Citraturic response to oral citric acid load

NASA Technical Reports Server (NTRS)

Sakhaee, K.; Alpern, R.; Poindexter, J.; Pak, C. Y.

1992-01-01

It is possible that some orally administered citrate may appear in urine by escaping oxidation in vivo. To determine whether this mechanism contributes to the citraturic response to potassium citrate, we measured serum and urinary citrate for 4 hours after a single oral load of citric acid (40 mEq.) in 6 normal subjects. Since citric acid does not alter acid-base balance, the effect of absorbed citrate could be isolated from that of alkali load. Serum citrate concentration increased significantly (p less than 0.05) 30 minutes after a single oral dose of citric acid and remained significantly elevated for 3 hours after citric acid load. Commensurate with this change, urinary citrate excretion peaked at 2 hours and gradually decreased during the next 2 hours after citric acid load. In contrast, serum and urinary citrate remained unaltered following the control load (no drug). Differences of the citratemic and citraturic effects between phases were significant (p less than 0.05) at 2 and 3 hours. Urinary pH, carbon dioxide pressure, bicarbonate, total carbon dioxide and ammonium did not change at any time after citric acid load, and did not differ between the 2 phases. No significant difference was noted in serum electrolytes, arterialized venous pH and carbon dioxide pressure at any time after citric acid load and between the 2 phases. Thus, the citraturic and citratemic effects of oral citric acid are largely accountable by provision of absorbed citrate, which has escaped in vivo degradation.

Effect of Cuscuta chinensis on renal function in ischemia/reperfusion-induced acute renal failure rats.

PubMed

Shin, Sun; Lee, Yun Jung; Kim, Eun Ju; Lee, An Sook; Kang, Dae Gill; Lee, Ho Sub

2011-01-01

The kidneys play a central role in regulating water, ion composition and excretion of metabolic waste products in the urine. Cuscuta chinensis has been known as an important traditional Oriental medicine for the treatment of liver and kidney disorders. Thus, we studied whether an aqueous extract of Cuscuta chinensis (ACC) seeds has an effect on renal function parameters in ischemia/reperfusion-induced acute renal failure (ARF) rats. Administration of 250 mg/kg/day ACC showed that renal functional parameters including urinary excretion rate, osmolality, Na(+), K(+), Cl(-), creatinine clearance, solute-free water reabsorption were significantly recovered in ischemia/reperfusion-induced ARF. Periodic acid Schiff staining showed that administration of ACC improved tubular damage in ischemia/reperfusion-induced ARF. In immunoblot and immunohistological examinations, ischemia/reperfusion-induced ARF decreased the expressions of water channel AQP 2, 3 and sodium potassium pump Na,K-ATPase in the renal medulla. However, administration of ACC markedly incremented AQP 2, 3 and Na,K-ATPase expressions. Therefore, these data indicate that administration of ACC ameliorates regulation of the urine concentration and renal functions in rats with ischemia/reperfusion-induced ARF.

Urinary acrylamide metabolites as biomarkers for short-term dietary exposure to acrylamide.

PubMed

Bjellaas, Thomas; Stølen, Linn Helene; Haugen, Margaretha; Paulsen, Jan Erik; Alexander, Jan; Lundanes, Elsa; Becher, Georg

2007-06-01

It has previously been reported that heat-treated carbohydrate rich foods may contain high levels of acrylamide resulting in consumers being inadvertently exposed to acrylamide. Acrylamide is mainly excreted in the urine as mercapturic acid derivatives of acrylamide and glycidamide. In a clinical study comprising of 53 subjects, the urinary excretion of these metabolites was determined using solid-phase extraction and liquid chromatography with positive electrospray MS/MS detection. The median (range) total excretion of acrylamide in urine during 24 h was 16 (7-47) microg acrylamide for non-smokers and 74 (38-106) microg acrylamide for smokers, respectively. It was found that the median intake estimate in the study based on 24 h dietary recall was 21 (13-178) and 26 (12-67) for non-smokers and smokers, respectively. The median dietary exposure to acrylamide was estimated to be 0.47 (range 0.17-1.16) microg/kg body weight per day. In a multiple linear regression analysis, the urinary excretion of acrylamide metabolites correlated statistically significant with intake of aspartic acid, protein, starch and coffee. Consumption of citrus fruits correlated negatively with excretion of acrylamide metabolites.

[Absence of effect of propranolol on urinary excretion of 3-methylhistidine in hyperthyroidism].

PubMed

Beylot, M; Riou, J P; Sautot, G; Mornex, R

Lean body mass and muscle protein breakdown were evaluated in euthyroid and hyperthyroid subjects by measuring the urinary excretion of creatinine and 3-methylhistidine. Since catecholamines probably have an inhibitory effect on muscle protein catabolism through a beta-receptor mechanism, the effects of propranolol on 3-methylhistidine excretion were also evaluated in hyperthyroid subjects. Hyperthyroid subjects had a lower lean body mass (34.9 +/- 6.3 kg versus 47.7 +/- 8.9 kg, p less than 0.001) and a greater 3-methylhistidine excretion (25.1 +/- 7.4 versus 19.0 +/- 4.8 mumol/mmol creatinine, p less than 0.05) than euthyroid subjects. Propranolol administered orally to hyperthyroid subjects decreased pulse rate (p less than 0.01) and plasma triiodothyronine concentrations (from 5.40 +/- 2.28 to 3.61 +/- 1.61 nmol/l, p less than 0.01), but did not modify urinary 3-methylhistidine excretion (24.8 +/- 8.7 versus 25.1 +/- 7.4 mumol/mmol creatinine). These results suggest that muscle wasting in hyperthyroidism is related to increased protein catabolism. This increased protein breakdown is not modified by short term administration of propranolol, a beta-blocking agent widely used in the management of hyperthyroidism.

Vitamin C activity of dehydroascorbic acid in humans--association between changes in the blood vitamin C concentration or urinary excretion after oral loading.

PubMed

Tsujimura, Masaru; Higasa, Shizu; Nakayama, Kazuhiro; Yanagisawa, Yoshiko; Iwamoto, Sadahiko; Kagawa, Yasuo

2008-08-01

We performed oral loading of AsA or DAsA (1 mmol) in subjects who had consumed a diet low in vitamin C (C) (C< or =5 mg/d) for 3 d before loading, and measured urinary and blood vitamin C. Since the crossover method was used, the same experiment was repeated after an interval of about 1 mo in each subject. The results of the experiment including a total of 17 subjects for 2005 and 2006, were as follows. (1) There were marked individual differences in urinary C excretion. (2) The C level in 24-h urine after C loading did not differ between the two orally administered C forms (AsA and DAsA). (3) C excretion between 0 and 3 h after C loading was significantly higher (p<0.05) for the DAsA group, while those between 3 and 6, 6 and 9, 9 and 12, and 12 and 24 h after C loading were significantly higher (p<0.05 or p<0.01) for the AsA group. (4) The blood C concentration and the increase in C 1 h after C loading were significantly higher (p<0.05 and p<0.01, respectively) in the DAsA than in the AsA group. (5) Evaluation of the association between C metabolism and the single nucleotide polymorphisms of glutathione S-transferase P (GSTP) 1-1 showed a lower urinary C excretion and a significantly lower C level in 24-h urine (p<0.05) after AsA loading, and a significantly lower urinary C excretion between 0 and 3 h after DAsA loading (p<0.05) for the GA heterozygotes than for the AA homozygotes. Considering the activity of C as DAsA in humans, based on urinary and blood C levels after a single loading of C, the utilization of DAsA is equivalent to that of AsA, although the metabolic turnover time is different. The involvement of polymorphisms in the xenobiotic metabolizing enzyme, GSTP1-1, in C metabolism, particularly urinary C excretion, was also clarified. This demonstrates the necessity of considering gene polymorphisms in determining individual C requirements. An abstract of this paper was reported by the Vitamin C Research Committee (Ochanomizu University) in 2007.

Factors Associated With High Sodium Intake Based on Estimated 24-Hour Urinary Sodium Excretion: The 2009-2011 Korea National Health and Nutrition Examination Survey.

PubMed

Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

2016-03-01

Although reducing dietary salt consumption is the most cost-effective strategy for preventing progression of cardiovascular and renal disease, policy-based approaches to monitor sodium intake accurately and the understanding factors associated with excessive sodium intake for the improvement of public health are lacking. We investigated factors associated with high sodium intake based on the estimated 24-hour urinary sodium excretion, using data from the 2009 to 2011 Korea National Health and Nutrition Examination Survey (KNHANES). Among 21,199 adults (≥19 years of age) who participated in the 2009 to 2011 KNHANES, 18,000 participants (weighted n = 33,969,783) who completed urinary sodium and creatinine evaluations were analyzed in this study. The 24-hour urinary sodium excretion was estimated using Tanaka equation. The mean estimated 24-hour urinary sodium excretion level was 4349 (4286-4413) mg per day. Only 18.5% (weighted n = 6,298,481/3,396,973, unweighted n = 2898/18,000) of the study participants consumed less the 2000 mg sodium per day. Female gender (P < 0.001), older age (P < 0.001), total energy intake ≥50 percentile (P < 0.005), and obesity (P < 0.001) were associated with high sodium intake, even after adjusting for potential confounders. Senior high school/college graduation in education and managers/professionals in occupation were associated with lower sodium intake (P < 0.001). According to hypertension management status, those who had hypertension without medication consumed more sodium than those who were normotensive. However, those who receiving treatment for hypertension consumed less sodium than those who were normotensive (P < 0.001). The number of family members, household income, and alcohol drinking did not affect 24-hour urinary sodium excretion. The logistic regression analysis for the highest estimated 24-hour urinary sodium excretion quartile (>6033 mg/day) using the abovementioned variables as covariates yielded identical results. Our data suggest that age, sex, education level, occupation, total energy intake, obesity, and hypertension management status are associated with excessive sodium intake in Korean adults using nationally representative data. Factors associated with high sodium intake should be considered in policy-based interventions to reduce dietary salt consumption and prevent cardiovascular disease as a public health target.

Early Biochemical Effects of an Organic Mercury Fungicide on Infants: ``Dose Makes the Poison''

NASA Astrophysics Data System (ADS)

Gotelli, Carlos A.; Astolfi, Emilio; Cox, Christopher; Cernichiari, Elsa; Clarkson, Thomas W.

1985-02-01

Phenylmercury absorbed through the skin from contaminated diapers affected urinary excretion in infants in Buenos Aires. The effects were reversible and quantitatively related to the concentration of urinary mercury. Excretion of γ -glutamyl transpeptidase, an enzyme in the brush borders of renal tubular cells, increased in a dose-dependent manner when mercury excretion exceeded a ``threshold'' value. Urine volume also increased but at a higher threshold with respect to mercury. The results support the threshold concept of the systemic toxicity of metals. γ -Glutamyl transpeptidase is a useful and sensitive marker for preclinical effects of toxic metals.

Association of urinary sodium/creatinine ratio with bone mineral density in postmenopausal women: KNHANES 2008-2011.

PubMed

Kim, Sung-Woo; Jeon, Jae-Han; Choi, Yeon-Kyung; Lee, Won-Kee; Hwang, In-Ryang; Kim, Jung-Guk; Lee, In-Kyu; Park, Keun-Gyu

2015-08-01

Accumulating evidence shows that high sodium chloride intake increases urinary calcium excretion and may be a risk factor for osteoporosis. However, the effect of oral sodium chloride intake on bone mineral density (BMD) and risk of osteoporosis has been inadequately researched. The aim of the present study was to determine whether urinary sodium excretion (reflecting oral sodium chloride intake) associates with BMD and prevalence of osteoporosis in postmenopausal women. This cross-sectional study involved a nationally representative sample consisting of 2,779 postmenopausal women who participated in the Korea National Health and Nutritional Examination Surveys in 2008-2011. The association of urinary sodium/creatinine ratio with BMD and other osteoporosis risk factors was assessed. In addition, the prevalence of osteoporosis was assessed in four groups with different urinary sodium/creatinine ratios. Participants with osteoporosis had significantly higher urinary sodium/creatinine ratios than the participants without osteoporosis. After adjusting for multiple confounding factors, urinary sodium/creatinine ratio correlated inversely with lumbar spine BMD (P = 0.001). Similarly, when participants were divided into quartile groups according to urinary sodium/creatinine ratio, the average BMD dropped as the urinary sodium/creatinine ratio increased. Multiple logistic regression analysis revealed that compared to quartile 1, quartile 4 had a significantly increased prevalence of lumbar spine osteoporosis (odds ratios 1.346, P for trend = 0.044). High urinary sodium excretion was significantly associated with low BMD and high prevalence of osteoporosis in lumbar spine. These results suggest that high sodium chloride intake decreases lumbar spine BMD and increases the risk of osteoporosis in postmenopausal women.

Urinary oxalate to creatinine ratios in healthy Turkish schoolchildren.

PubMed

Dursun, Ismail; Çelik, İlknur; Poyrazoglu, Hakan M; Köse, Kader; Tanrıkulu, Esen; Sahin, Habibe; Yılmaz, Kenan; Öztürk, Ahmet; Yel, Sibel; Gündüz, Zübeyde; Düşünsel, Ruhan

2017-11-01

we aimed to establish reference values for urinary oxalate to creatinine ratios in healthy children aged 6-15 years and to investigate the relationship between their nutritional habits and oxalate excretion. Random urine specimens from 953 healthy children aged 6-15 years were obtained and analyzed for oxalate and creatinine. Additionally, a 24-h dietary recall form was prepared and given to them. The ingredient composition of the diet was calculated. The children were divided into three groups according to age: Group I (69 years, n = 353), Group II (10-12 years, n = 335), and Group III (13-15 years, n = 265). The 95th percentile of the oxalate to creatinine ratio for subjects aged 6-9, 10-12, and 13-15 years were 0.048, 0.042, and 0.042 mg/mg, respectively. The oxalate to creatinine ratio was significantly higher in Group 1 than in Group 2 and Group 3. Urinary oxalate excretion was positively correlated with increased protein intake and negatively correlated with age. A significant positive correlation was determined between urinary oxalate excretion and the proline, serine, protein, and glycine content of diet. Dietary proline intake showed a positive correlation with the urine oxalate to creatinine ratio and was found to be an independent predictor for urinary oxalate. These data lend support to the idea that every country should have its own normal reference values to determine the underlying metabolic risk factor for kidney stone disease since regional variation in the dietary intake of proteins and other nutrients can affect normal urinary excretion of oxalate.

The relationship between cognitive function, depressive behaviour and sleep quality with 24-h urinary sodium excretion in patients with essential hypertension.

PubMed

Afsar, Baris

2013-03-01

Various studies have shown that sodium intake is related to increased blood pressure. However, the relationship between sodium intake and cognitive function and depression has not previously been studied. The objective of this study was to investigate the relationship between 24-h sodium excretion with cognitive function, depression and sleep quality in patients newly diagnosed with essential hypertension. All patients underwent history taking, physical examination, blood pressure measurement, 12-lead ECG evaluation, routine urine analysis, biochemical analysis and 24-h urine collection to measure urinary sodium and protein excretion and creatinine clearance, evaluation of cognitive function, depressive behaviour and sleep quality. In total, 119 patients newly diagnosed with essential hypertension (50 men and 69 women aged 54.2 ± 16.1 years) were enrolled. The 24-h urinary sodium excretion of the patients was 204.0 ± 240.4 mEq/day. The Standardized Mini Mental State Examination (SMMSE), Pittsburgh Sleep Quality Index and Beck Depression Inventory scores of the patients were 26.0 ± 2.7, 5.6 ± 3.1 and 21.6 ± 13.5, respectively. Spearman correlation analysis revealed that 24-h urinary sodium excretion was correlated with age (rho -0.258, p = 0.005), systolic blood pressure (rho 0.219, p = 0.017), diastolic blood pressure (rho 0.195, p = 0.034), creatinine clearance (rho 0.414, p < 0.0001) and SMMSE score (rho -0.257, p = 0.005). Stepwise linear regression of independent factors revealed that gender (p < 0.0001), creatinine clearance (p < 0.0001), systolic blood pressure (p = 0.031) and SMMSE score (p < 0.0001) were independently related to logarithmically converted 24-h sodium excretion. The current study demonstrated that better cognitive function, but not depressive behaviour and sleep disturbance, is related to decreased sodium intake as evaluated by 24-h urinary sodium excretion. Studies are needed to highlight the mechanisms regarding the relationship between cognitive function and sodium intake.

Diagnostic Value of Urinary Mevalonic Acid Excretion in Patients with a Clinical Suspicion of Mevalonate Kinase Deficiency (MKD).

PubMed

Jeyaratnam, Jerold; Ter Haar, Nienke M; de Sain-van der Velden, Monique G M; Waterham, Hans R; van Gijn, Mariëlle E; Frenkel, Joost

2016-01-01

In patients suffering from mevalonate kinase deficiency (MKD), the reduced enzyme activity leads to an accumulation of mevalonic acid which is excreted in the urine. This study aims to evaluate the diagnostic value of urinary mevalonic acid measurement in patients with a clinical suspicion of mevalonate kinase deficiency. In this single-center, retrospective analysis, all patients in whom both measurement of mevalonic acid and genetic testing had been performed in the preceding 17 years have been included. The presence of two pathogenic MVK mutations or demonstration of decreased enzyme activity was considered to be the gold standard for the diagnosis of MKD. Sixty-one patients were included in this study. Thirteen of them harbored two MVK mutations; twelve of them showed elevated levels of mevalonic acid. Forty-eight patients did not harbor any MVK mutations, yet five of them excreted increased amounts of mevalonic acid. This corresponds to a sensitivity of 92%, a specificity of 90%, a positive predictive value of 71%, and a negative predictive value of 98%. The positive likelihood ratio is 10 and the negative likelihood ratio is 0.09. MKD seems very unlikely in patients with a normal mevalonic acid excretion, but it cannot be excluded completely. Further, a positive urinary mevalonic acid excretion still requires MVK analysis to confirm the diagnosis of MKD. Therefore, detection of urinary mevalonic acid should not be mandatory before genetic testing. However, as long as genetic testing is not widely available and affordable, measurement of urinary mevalonic acid is a fair way to select patients for MVK gene analysis or enzyme assay.

Long-term impact of systolic blood pressure and glycemia on the development of microalbuminuria in essential hypertension.

PubMed

Pascual, Jose Maria; Rodilla, Enrique; Gonzalez, Carmen; Pérez-Hoyos, Santiago; Redon, Josep

2005-06-01

The objective was to assess the temporal impact of factors related to the development of microalbuminuria during the follow-up of young adult normoalbuminurics with high-normal blood pressure or at stage 1 of essential hypertension. Prospective follow-up was conducted on 245 normoalbuminuric hypertensive subjects (mean age 40.9 years; 134 men; blood pressure 139.7/88.6 mm Hg; body mass index 28.5 kg/m2) never treated previously with antihypertensive drugs, with yearly urinary albumin excretion measurements, until the development of microalbuminuria. After enrollment, patients were placed on usual care including nonpharmacological treatment or with an antihypertensive drug regime to achieve a blood pressure of <135/85 mm Hg. Thirty subjects (12.2%) developed microalbuminuria after a mean follow-up of 29.9 months (range 12 to 144 months), 2.5 per 100 patients per year. Baseline urinary albumin excretion (hazard ratio, 1.07; P=0.006) and systolic blood pressure during the follow-up (hazard ratio, 1.03; P=0.008) were independent factors related to the follow-up urinary albumin excretion in a Cox proportional hazard model. A significant increase in the risk of developing microalbuminuria for urinary albumin excretion at baseline >15 mg per 24-hour systolic blood pressure >139 mm Hg and a positive trend in fasting glucose were observed in the univariate analyses. However, in the multivariate analysis, only the baseline urinary albumin excretion and the trend of fasting glucose were independently related to the risk of developing microalbuminuria. In mild hypertensives, the development of microalbuminuria was linked to insufficient blood pressure control and to a progressive increment of glucose values.

Clarithromycin, trimethoprim, and penicillin and oxidative nucleic acid modifications in humans: randomised, controlled trials.

PubMed

Larsen, Emil List; Cejvanovic, Vanja; Kjaer, Laura Kofoed; Pedersen, Morten Thorup; Popik, Sara Daugaard; Hansen, Lina Kallehave; Andersen, Jon Traerup; Jimenez-Solem, Espen; Broedbaek, Kasper; Petersen, Morten; Weimann, Allan; Henriksen, Trine; Lykkesfeldt, Jens; Torp-Pedersen, Christian; Poulsen, Henrik Enghusen

2017-08-01

In vitro studies have demonstrated that formation of reactive oxygen species (ROS) contributes to the effect of bactericidal antibiotics. The formation of ROS is not restricted to bacteria, but also occurs in mammalian cells. Oxidative stress is linked to several diseases. This study investigates whether antibiotic drugs induce oxidative stress in healthy humans as a possible mechanism for adverse reactions to the antibiotic drugs. This study contains information from two randomised, controlled trials. Participants underwent 1 week treatment with clarithromycin, trimethoprim, phenoxymethylpenicillin (penicillin V), or placebo. Oxidative modifications were measured as 24-h urinary excretion of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo), and plasma levels of malondialdehyde before and after treatment as a measurement of DNA oxidation, RNA oxidation, and lipid peroxidation, respectively. Clarithromycin significantly increased urinary excretion of 8-oxodG by 22.0% (95% confidence interval (CI): 3.6-40.4%) and 8-oxoGuo by 14.9% (95% CI: 3.7-26.1%). Further, we demonstrated that trimethoprim significantly lowered urinary excretion of 8-oxodG by 21.7% (95% CI: 5.8-37.6%), but did not influence urinary excretion of 8-oxoGuo. Penicillin V did not influence urinary excretion of 8-oxodG or 8-oxoGuo. None of the antibiotic drugs influenced plasma levels of malondialdehyde. Clarithromycin significantly increases oxidative nucleic acid modifications. Increased oxidative modifications might explain some of clarithromycin's known adverse reactions. Trimethoprim significantly lowers DNA oxidation but not RNA oxidation. Penicillin V had no effect on oxidative nucleic acid modifications. © 2017 The British Pharmacological Society.

Urinary excretion of uric acid is negatively associated with albuminuria in patients with chronic kidney disease: a cross-sectional study.

PubMed

Li, Fengqin; Guo, Hui; Zou, Jianan; Chen, Weijun; Lu, Yijun; Zhang, Xiaoli; Fu, Chensheng; Xiao, Jing; Ye, Zhibin

2018-04-24

Increasing evidence has shown that albuminuria is related to serum uric acid. Little is known about whether this association may be interrelated via renal handling of uric acid. Therefore, we aim to study urinary uric acid excretion and its association with albuminuria in patients with chronic kidney disease (CKD). A cross-sectional study of 200 Chinese CKD patients recruited from department of nephrology of Huadong hospital was conducted. Levels of 24 h urinary excretion of uric acid (24-h Uur), fractional excretion of uric acid (FEur) and uric acid clearance rate (Cur) according to gender, CKD stages, hypertension and albuminuria status were compared by a multivariate analysis. Pearson and Spearman correlation and multiple regression analyses were used to study the correlation of 24-h Uur, FEur and Cur with urinary albumin to creatinine ratio (UACR). The multivariate analysis showed that 24-h Uur and Cur were lower and FEur was higher in the hypertension group, stage 3-5 CKD and macro-albuminuria group (UACR> 30 mg/mmol) than those in the normotensive group, stage 1 CKD group and the normo-albuminuria group (UACR< 3 mg/mmol) (all P < 0.05). Moreover, males had higher 24-h Uur and lower FEur than females (both P < 0.05). Multiple linear regression analysis showed that UACR was negatively associated with 24-h Uur and Cur (P = 0.021, P = 0.007, respectively), but not with FEur (P = 0.759), after adjusting for multiple confounding factors. Our findings suggested that urinary excretion of uric acid is negatively associated with albuminuria in patients with CKD. This phenomenon may help to explain the association between albuminuria and serum uric acid.

Role of renal metabolism and excretion in 5-nitrofuran-induced uroepithelial cancer in the rat.

PubMed Central

Spry, L A; Zenser, T V; Cohen, S M; Davis, B B

1985-01-01

5-Nitrofurans have been used in the study of chemical carcinogenesis. There is substantial evidence that N-[4-(5-nitro-2-furyl)-2-thiazolyl] formamide (FANFT) is deformylated to 2-amino-4-(5-nitro-2-furyl)thiazole (ANFT) in the process of FANFT-induced bladder cancer. Paradoxically, ANFT is less potent as a uroepithelial carcinogen than FANFT when fed to rats. Feeding aspirin with FANFT to rats decreases the incidence of bladder cancer. Isolated kidneys were perfused with 5-nitrofurans to determine renal clearances and whether aspirin acts to decrease urinary excretion of the carcinogen. In FANFT-perfused kidneys, FANFT was deformylated to ANFT and excreted (1.06 +/- 0.22 nmol/min) at a rate eightfold higher than excretion of FANFT. In kidneys perfused with equimolar ANFT, excretion of ANFT was 0.25 +/- 0.05 nmol/min, which suggests a coupling of renal deformylation of FANFT to excretion of ANFT in FANFT-perfused kidneys. Neither aspirin nor probenecid altered the urinary excretion or half-life of FANFT or ANFT. In rats fed 0.2% FANFT as part of their diet, coadministration of aspirin (0.5%) increased urinary excretion of ANFT during a 12-wk feeding study, which suggests decreased tissue binding or metabolism of ANFT. Kidney perfusion with acetylated ANFT (NFTA), a much less potent uroepithelial carcinogen, resulted in no ANFT excretion or accumulation, which indicates the specificity of renal deformylase. Renal deformylase activity was found in broken cell preparations of rat and human kidney. These data describe a unique renal metabolic/excretory coupling for these compounds that appears to explain the differential carcinogenic potential of the 5-nitrofurans tested. These results are consistent with the hypothesis that aspirin decreases activation of ANFT by inhibiting prostaglandin H synthase. PMID:4044826

Nonsteroidal Anti-Inflammatory Drugs and the Kidney

PubMed Central

Hörl, Walter H.

2010-01-01

Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit the isoenzymes COX-1 and COX-2 of cyclooxygenase (COX). Renal side effects (e.g., kidney function, fluid and urinary electrolyte excretion) vary with the extent of COX-2-COX-1 selectivity and the administered dose of these compounds. While young healthy subjects will rarely experience adverse renal effects with the use of NSAIDs, elderly patients and those with co-morbibity (e.g., congestive heart failure, liver cirrhosis or chronic kidney disease) and drug combinations (e.g., renin-angiotensin blockers, diuretics plus NSAIDs) may develop acute renal failure. This review summarizes our present knowledge how traditional NSAIDs and selective COX-2 inhibitors may affect the kidney under various experimental and clinical conditions, and how these drugs may influence renal inflammation, water transport, sodium and potassium balance and how renal dysfunction or hypertension may result. PMID:27713354

Lower body negative pressure treadmill exercise as a countermeasure for bed rest-induced bone loss in female identical twins.

PubMed

Zwart, Sara R; Hargens, Alan R; Lee, Stuart M C; Macias, Brandon R; Watenpaugh, Donald E; Tse, Kevin; Smith, Scott M

2007-02-01

Supine weight-bearing exercise within lower body negative pressure (LBNP) alleviates some of the skeletal deconditioning induced by simulated weightlessness in men. We examined this potential beneficial effect in women. Because dietary acid load affected the degree of bone resorption in men during bed rest, we also investigated this variable in women. Subjects were 7 pairs of female identical twins assigned at random to 2 groups, sedentary bed rest (control) or bed rest with supine treadmill exercise within LBNP. Dietary intake was controlled and monitored. Urinary calcium and markers of bone resorption were measured before bed rest and on bed rest days 5/6, 12/13, 19/20, and 26/27. Bone mineral content was assessed by dual-energy X-ray absorptiometry before and after bed rest. Data were analyzed by repeated-measures two-way analysis of variance. Pearson correlation coefficients were used to define the relationships between diet and markers of bone metabolism and to estimate heritability of markers. During bed rest, all markers of bone resorption and urinary calcium and phosphorus increased (P<0.001); parathyroid hormone (P=0.06), bone-specific alkaline phosphatase (P=0.06), and 1,25-dihydroxyvitamin D (P=0.09) tended to decrease. LBNP exercise tended to mitigate bone density loss. The ratio of dietary animal protein to potassium was positively correlated with urinary calcium excretion for all weeks of bed rest in the control group, but only during weeks 1 and 3 in the exercise group. Pre-bed rest data suggested that many markers of bone metabolism have strong genetic determinants. Treadmill exercise within LBNP had less of a protective effect on bone resorption during bed rest in women than previously published results had shown for its effect in men, but the same trends were observed for both sexes. Dietary acid load of these female subjects was significantly correlated with calcium excretion but not with other bone resorption markers.

Lower body negative pressure treadmill exercise as a countermeasure for bed rest-induced bone loss in female identical twins

PubMed Central

Zwart, Sara R.; Hargens, Alan R.; Lee, Stuart M. C.; Macias, Brandon R.; Watenpaugh, Donald E.; Tse, Kevin; Smith, Scott M.

2007-01-01

Supine weight-bearing exercise within lower body negative pressure (LBNP) alleviates some of the skeletal deconditioning induced by simulated weightlessness in men. We examined the potential beneficial effect in women. Because dietary acid load affected the degree of bone resorption in men during bed rest, we also investigated this variable in women. Subjects were 7 pairs of female identical twins assigned at random to 2 groups, sedentary bed rest (control) or bed rest with supine treadmill exercise within LBNP. Dietary intake was controlled and monitored. Urinary calcium and markers of bone resorption were measured before bed rest (BR) and on BR days 5/6, 12/13, 19/20, and 26/27. Bone mineral content was assessed by dual-energy X-ray absorptiometry before and after bed rest. Data were analyzed by repeated measures two-way analysis of variance. Pearson correlation coefficients were used to define the relationships between diet and markers of bone metabolism, and to estimate heritability of markers. During bed rest, all markers of bone resorption and urinary calcium and phosphorus increased (P < 0.001); parathyroid hormone (P = 0.06), bone-specific alkaline phosphatase (P = 0.06), and 1,25-dihydroxyvitamin D (P = 0.09) tended to decrease. LBNP exercise tended to mitigate bone density loss. The ratio of dietary animal protein to potassium was positively correlated with urinary calcium excretion for all weeks of bed rest in the control group, but only during weeks 1 and 3 for the exercise group. Pre-bed rest data suggested that many markers of bone metabolism have strong genetic determinants. Treadmill exercise within LBNP had less of a protective effect on bone resorption during bed rest in women than previously-published results had shown for its effect in men, but the same trends were observed for both sexes. Dietary acid load of these female subjects was significantly correlated with calcium excretion but not with other bone resorption markers. PMID:17070743

Dietary Intake Can Predict and Protect Against Changes in Bone Metabolism during Spaceflight and Recovery (Pro K)

NASA Technical Reports Server (NTRS)

Smith, Scott M.; Zwart, S. R.; Shackelford, L.; Heer, M.

2009-01-01

Bone loss is not only a well-documented effect of spaceflight on astronauts, but also a condition that affects millions of men and women on Earth each year. Many countermeasures aimed at preventing bone loss during spaceflight have been proposed, and many have been evaluated to some degree. To date, those showing potential have focused on either exercise or pharmacological interventions, but none have targeted dietary intake alone as a factor to predict or minimize bone loss during spaceflight. The "Dietary Intake Can Predict and Protect against Changes in Bone Metabolism during Spaceflight and Recovery" investigation ("Pro K") is one of the first inflight evaluations of a dietary countermeasure to lessen bone loss of astronauts. This protocol will test the hypothesis that the ratio of acid precursors to base precursors (specifically animal protein to potassium) in the diet can predict directional changes in bone mineral during spaceflight and recovery. The ratio of animal protein to potassium in the diet will be controlled for multiple short (4-day) periods before and during flight. Based on multiple sets of bed rest data, we hypothesize that a higher ratio of the intake of animal protein to the intake of potassium will yield higher concentrations of markers of bone resorption and urinary calcium excretion during flight and during recovery from bone mineral loss after long-duration spaceflight.

Comparison of hypotensive, diuretic and renal effects between cladodes of Opuntia ficus-indica and furosemide.

PubMed

Bakour, Meryem; Al-Waili, Noori; El-Haskoury, Redouan; El-Menyiy, Nawal; Al-Waili, Thia; Al-Waili, Ali; Lyoussi, Badiaa

2017-09-01

To investigate the diuretic, hypotensive and renal effect of Opuntia ficus-indica in two different species in oral and intravenous administration. Diuretic activity was evaluated in rats with the plant cladode gel and aqueous extract administrated orally, and was evaluated in rabbits with plant extract administered intravenously. Single and repeated doses of cladode gel or aqueous extract of cladode were tested. Urine volume and blood and urine creatinine, sodium and potassium were measured, and creatinine clearance was calculated. The hypotensive effect of lyophilized extract of cladode was evaluated in rabbits. Two polyethylene PE50 catheters were used: one in the jugular vein for the infusion of the plant extract and the other in the carotid for the evaluation of the arterial pressure. The cladode gel or aqueous extract increased urine volume, creatinine clearance and urinary excretion of sodium and potassium without significant effect on serum creatinine or blood urea. Furosemide, gel and aqueous extract of cladode insignificantly lowered plasma potassium in rats. Intravenous administration of the lyophilized extract caused a significant decrease in mean arterial pressure in rabbits with a significant increase in urine volume and urine sodium and potassium; the effect was dose dependent. Intravenous administration of lyophilized extract did not affect plasma sodium or potassium. Gel and aqueous extract of Opuntia ficus-indica cladode have a significant diuretic effect on rats, and the lyophilized extract has a diuretic and hypotensive effect on normotensive rabbits without deterioration in renal function test. Additional studies on active ingredients are essential to pave the way for clinical studies on diuretic and hypotensive effect of the plant. Copyright © 2017 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.

Novel evidence that nitric oxide of the medial septal area influences the salivary secretion induced by pilocarpine.

PubMed

Saad, Wilson Abrão; Guarda, Ismael Francisco Motta Siqueira; Camargo, Luiz Antonio de Arruda; dos Santos, Talmir Augusto Faria Brisola; Saad, William Abrão; Simões, Sylvio; Guarda, Renata Saad

2002-04-05

Our studies have focused on the effect of injection of L-NAME and sodium nitroprussiate (SNP) on the salivary secretion, arterial blood pressure, sodium excretion and urinary volume induced by pilocarpine which was injected into the medial septal area (MSA). Rats were anesthetized with urethane (1.25 g/kg b. wt.) and a stainless steel cannula was implanted into their MSA. The amount of saliva secretion was studied over a five-minute period after injection of pilocarpine into MSA. Injection of pilocarpine (10, 20, 40, 80, 160 microg/microl) into MSA produced a dose-dependent increase in salivary secretion. L-NG-nitro arginine methyl-esther (L-NAME) (40 microg/microl), a nitric oxide (NO) synthase inhibitor, was injected into MSA prior to the injection of pilocarpine into MSA, producing an increase in salivary secretion due to the effect of pilocarpine. Sodium nitroprussiate (SNP) (30 microg/microl) was injected into MSA prior to the injection of pilocarpine into MSA attenuating the increase in salivary secretion induced by pilocarpine. Medial arterial pressure (MAP) increase after injections of pilocarpine into the MSA. L-NAME injected into the MSA prior to injection of pilocarpine into MSA increased the MAP. SNP injected into the MSA prior to pilocarpine attenuated the effect of pilocarpine on MAP. Pilocarpine (40 ug/ul) injected into the MAS induced an increase in sodium and urinary excretion. L-NAME injected prior to pilocarpine into the MSA increased the urinary sodium excretion and urinary volume induced by pilocarpine. SNP injected prior to pilocarpine into the MSA decreased the sodium excretion and urinary volume induced by pilocarpine. All these roles of pilocarpine depend on the release of nitric oxide into the MSA. We may also conclude that the MSA is involved with the cholinergic excitatory mechanism that induce salivary secretion, increase in MAP and increase in sodium excretion and urinary volume.

Hormonal changes during 17 days of head-down bed-rest

NASA Technical Reports Server (NTRS)

Custaud, Marc-Antoine; Arnaud, Sara B.; Monk, Timothy H.; Claustrat, Bruno; Gharib, Claude; Gauquelin-Koch, Guillemette

2003-01-01

We investigated in six men the impact of 17 days of head-down bed rest (HDBR) on the daily rhythms of the hormones involved in hydroelectrolytic regulation. This HDBR study was designed to mimic a real space flight. Urine samples were collected at each voiding before, during and after HDBR. Urinary excretion of Growth Hormone (GH), Cortisol, 6 Sulfatoxymelatonin, Normetadrenaline (NMN) and Metadrenaline (NM) was determined. A decrease in urinary cortisol excretion during the night of HDBR was noted. For GH, a rhythm was found before and during HDBR. The rhythm of melatonin, evaluated with the urine excretion of 6 Sulfatoxymelatonin (aMT6S), the main hepatic metabolite, persisted throughout the experiment without any modification to the level of phase. A decrease during the night was noted for normetadrenaline urinary derivates, but only during the HDBR.

Sodium Excretion and the Risk of Cardiovascular Disease in Patients With Chronic Kidney Disease

PubMed Central

Mills, Katherine T.; Chen, Jing; Yang, Wei; Appel, Lawrence J.; Kusek, John W.; Alper, Arnold; Delafontaine, Patrice; Keane, Martin G.; Mohler, Emile; Ojo, Akinlolu; Rahman, Mahboob; Ricardo, Ana C.; Soliman, Elsayed Z.; Steigerwalt, Susan; Townsend, Raymond; He, Jiang

2016-01-01

IMPORTANCE Patients with chronic kidney disease (CKD) are at an increased risk of cardiovascular disease (CVD) compared with the general population. Prior studies have produced contradictory results on the association of dietary sodium intake with risk of CVD, and this relationship has not been investigated in patients with CKD. OBJECTIVE To evaluate the association between urinary sodium excretion and clinical CVD events among patients with CKD. DESIGN, SETTING, AND PARTICIPANTS A prospective cohort study of patients with CKD from 7 locations in the United States enrolled in the Chronic Renal Insufficiency Cohort Study and followed up from May 2003 to March 2013. EXPOSURES The cumulative mean of urinary sodium excretion from three 24-hour urinary measurements and calibrated to sex-specific mean 24-hour urinary creatinine excretion. MAIN OUTCOMES AND MEASURES A composite of CVD events defined as congestive heart failure, stroke, ormyocardial infarction. Events were reported every 6 months and confirmed by medical record adjudication. RESULTS Among 3757 participants (mean age, 58 years; 45% women), 804 composite CVD events (575 heart failure, 305 myocardial infarction, and 148 stroke) occurred during a median 6.8 years of follow-up. From lowest (<2894 mg/24 hours) to highest (≥4548 mg/24 hours) quartile of calibrated sodium excretion, 174, 159, 198, and 273 composite CVD events occurred, and the cumulative incidence was 18.4%, 16.5%, 20.6%, and 29.8% at median follow-up. In addition, the cumulative incidence of CVD events in the highest quartile of calibrated sodium excretion compared with the lowest was 23.2% vs 13.3% for heart failure, 10.9% vs 7.8% for myocardial infarction, and 6.4% vs 2.7% for stroke at median follow-up. Hazard ratios of the highest quartile compared with the lowest quartile were 1.36 (95% CI, 1.09–1.70; P = .007) for composite CVD events, 1.34 (95% CI, 1.03–1.74; P = .03) for heart failure, and 1.81 (95% CI, 1.08–3.02; P = .02) for stroke after multivariable adjustment. Restricted cubic spline analyses of the association between sodium excretion and composite CVD provided no evidence of a nonlinear association (P = .11) and indicated a significant linear association (P < .001). CONCLUSIONS AND RELEVANCE Among patients with CKD, higher urinary sodium excretion was associated with increased risk of CVD. PMID:27218629

Impact of Dietary Calcium and Oxalate, and Oxalobacter Formigenes Colonization on Urinary Oxalate Excretion

PubMed Central

Jiang, Juquan; Knight, John; Easter, Linda H.; Neiberg, Rebecca; Holmes, Ross P.; Assimos, Dean G.

2011-01-01

Purpose Enteric colonization with Oxalobacter formigenes, a bacterium whose main energy source is oxalate, has been demonstrated to decrease the risk of recurrent calcium oxalate kidney stone formation. We assessed the impact of diets controlled in calcium and oxalate contents on urinary and fecal analytes in healthy subjects who were naturally colonized with O. formigenes or not colonized with O. formigenes. Materials and Methods A total of 11 O. formigenes colonized and 11 noncolonized subjects were administered diets controlled in calcium and oxalate contents. We assayed 24-hour urine collections and stool samples obtained on the last 4 days of each 1-week diet for stone risk parameters and O. formigenes levels. Mixed model analysis was used to determine the effects of colonization status on these variables. Results Urinary calcium and oxalate excretion were significantly altered by the dietary changes in O. formigenes colonized and noncolonized individuals. Mixed model analysis showed significant interaction between colonization status and oxalate excretion on a low calcium (400 mg daily)/moderate oxalate (250 mg daily) diet (p = 0.026). Urinary oxalate excretion was 19.5% lower in O. formigenes colonized subjects than in noncolonized subjects on the low calcium/moderate oxalate diet (mean ± SE 34.9 ± 2.6 vs 43.6 ± 2.6 mg, p = 0.031). Conclusions Results suggest that O. formigenes colonization decreases oxalate excretion during periods of low calcium and moderate oxalate intake. PMID:21575973

Urinary excretion of uranium in adult inhabitants of the Czech Republic.

PubMed

Malátová, Irena; Bečková, Věra; Kotík, Lukáš

2016-02-01

The main aim of this study was to determine and evaluate urinary excretion of uranium in the general public of the Czech Republic. This value should serve as a baseline for distinguishing possible increase in uranium content in population living near legacy sites of mining and processing uranium ores and also to help to distinguish the proportion of the uranium content in urine among uranium miners resulting from inhaled dust. The geometric mean of the uranium concentration in urine of 74 inhabitants of the Czech Republic was 0.091 mBq/L (7.4 ng/L) with the 95% confidence interval 0.071-0.12 mBq/L (5.7-9.6 ng/L) respectively. The geometric mean of the daily excretion was 0.15 mBq/d (12.4 ng/d) with the 95% confidence interval 0.12-0.20 mBq/d (9.5-16.1 ng/d) respectively. Despite the legacy of uranium mines and plants processing uranium ore in the Czech Republic, the levels of uranium in urine and therefore, also human body content of uranium, is similar to other countries, esp. Germany, Slovenia and USA. Significant difference in the daily urinary excretion of uranium was found between individuals using public supply and private water wells as a source of drinking water. Age dependence of daily urinary excretion of uranium was not found. Mean values and their range are comparable to other countries, esp. Germany, Slovenia and USA. Copyright © 2015 Elsevier Ltd. All rights reserved.

Urinary levels of nickel and chromium associated with dental restoration by nickel–chromium based alloys

PubMed Central

Chen, Bo; Xia, Gang; Cao, Xin-Ming; Wang, Jue; Xu, Bi-Yao; Huang, Pu; Chen, Yue; Jiang, Qing-Wu

2013-01-01

This paper aims to investigate if the dental restoration of nickel–chromium based alloy (Ni–Cr) leads to the enhanced excretions of Ni and Cr in urine. Seven hundred and ninety-five patients in a dental hospital had single or multiple Ni–Cr alloy restoration recently and 198 controls were recruited to collect information on dental restoration by questionnaire and clinical examination. Urinary concentrations of Ni and Cr from each subject were measure by graphite furnace atomic absorption spectrometry. Compared to the control group, the urinary level of Ni was significantly higher in the patient group of <1 month of the restoration duration, among which higher Ni excretions were found in those with either a higher number of teeth replaced by dental alloys or a higher index of metal crown not covered with the porcelain. Urinary levels of Cr were significantly higher in the three patient groups of <1, 1 to <3 and 3 to <6 months, especially in those with a higher metal crown exposure index. Linear curve estimations showed better relationships between urinary Ni and Cr in patients within 6-month groups. Our data suggested significant increased excretions of urinary Ni and Cr after dental restoration. Potential short- and long-term effects of Ni–Cr alloy restoration need to be investigated. PMID:23579466

Urinary excretion of orally ingested gastrografin on CT.

PubMed

Apter, S; Gayer, G; Amitai, M; Hertz, M

1998-01-01

Renal excretion of orally ingested gastrografin has rarely been reported on computed tomography (CT). We studied the unenhanced scans of 82 patients with bowel disorders or perforation to assess the prevalence of urinary contrast material (CM) in various bowel diseases. We also assessed the clinical significance of this sign. In addition, we reviewed the unenhanced CT scans of 100 randomly selected patients without bowel diseases as a control group. Twenty-nine of the 58 patients with bowel diseases, six of nine with free perforation, and one of 15 with covered perforation had CM in the urinary tract. None of the 100 without bowel disease showed urinary CM. Statistical analysis was done by using the Fisher's exact test. The prevalence of urinary CM was highest in inflammatory bowel disease, radiation enteritis, and free perforation (p < 0. 0001). This study shows that the CT finding of orally ingested gastrografin in the urinary tract differentiates patients with bowel disease from those without.

Caffeine intake antagonizes salt sensitive hypertension through improvement of renal sodium handling

PubMed Central

Yu, Hao; Yang, Tao; Gao, Peng; Wei, Xing; Zhang, Hexuan; Xiong, Shiqiang; Lu, Zongshi; Li, Li; Wei, Xiao; Chen, Jing; Zhao, Yu; Arendshorst, William J.; Shang, Qianhui; Liu, Daoyan; Zhu, Zhiming

2016-01-01

High salt intake is a major risk factor for hypertension. Although acute caffeine intake produces moderate diuresis and natriuresis, caffeine increases the blood pressure (BP) through activating sympathetic activity. However, the long-term effects of caffeine on urinary sodium excretion and blood pressure are rarely investigated. Here, we investigated whether chronic caffeine administration antagonizes salt sensitive hypertension by promoting urinary sodium excretion. Dahl salt-sensitive (Dahl-S) rats were fed with high salt diet with or without 0.1% caffeine in drinking water for 15 days. The BP, heart rate and locomotor activity of rats was analyzed and urinary sodium excretion was determined. The renal epithelial Na+ channel (ENaC) expression and function were measured by in vivo and in vitro experiments. Chronic consumption of caffeine attenuates hypertension induced by high salt without affecting sympathetic nerve activity in Dahl-S rats. The renal α-ENaC expression and ENaC activity of rats decreased after chronic caffeine administration. Caffeine increased phosphorylation of AMPK and decrease α-ENaC expression in cortical collecting duct cells. Inhibiting AMPK abolished the effect of caffeine on α-ENaC. Chronic caffeine intake prevented the development of salt-sensitive hypertension through promoting urinary sodium excretion, which was associated with activation of renal AMPK and inhibition of renal tubular ENaC. PMID:27173481

Dietary exposure to 5-hydroxymethylfurfural from Norwegian food and correlations with urine metabolites of short-term exposure.

PubMed

Husøy, T; Haugen, M; Murkovic, M; Jöbstl, D; Stølen, L H; Bjellaas, T; Rønningborg, C; Glatt, H; Alexander, J

2008-12-01

5-Hydroxymethylfurfural (HMF) is formed in carbohydrate-rich food during acid-catalysed dehydration and in the Maillard reaction from reducing sugars. HMF is found in mg quantities per kg in various foods. HMF is mainly metabolised to 5-hydroxymethyl-2-furoic acid (HMFA), but unknown quantities of the mutagenic 5-sulphoxymethylfurfural (SMF) may also be formed, making HMF potentially hazardous to humans. We determined the HMF content in Norwegian food items and estimated the dietary intake of HMF in 53 volunteers by means of 24h dietary recall. The estimated intakes of HMF were correlated with urinary excretion of HMFA. Coffee, prunes, dark beer, canned peaches and raisins had the highest levels of HMF. The 95th percentile of the estimated daily dietary intake of HMF and the 24h urinary excretion of HMFA were 27.6 and 28.6mg, respectively. Coffee, dried fruit, honey and alcohol were identified as independent determinants of urinary HMFA excretion. Most participants had lower estimated HMF intake than the amount of HMFA excreted in urine. In spite of this there was a significant correlation (r=0.57, P<0.001) between the estimated HMF intake and urinary HMFA. Further studies are needed to reveal alternative sources for HMF exposure.

Variability of plasma and urine betaine in diabetes mellitus and its relationship to methionine load test responses: an observational study

PubMed Central

2012-01-01

Background Since betaine is an osmolyte and methyl donor, and abnormal betaine loss is common in diabetes mellitus (>20% patients), we investigated the relationship between betaine and the post-methionine load rise in homocysteine, in diabetes and control subjects. The post-methionine load test is reported to be both an independent vascular risk factor and a measure of betaine sufficiency. Methods Patients with type 2 diabetes (n = 34) and control subjects (n = 17) were recruited. We measured baseline fasting plasma and 4-hour post-methionine load (L-methionine, 0.1 mg/kg body weight) concentrations of homocysteine, betaine, and the betaine metabolite N,N-dimethylglycine. Baseline urine excretions of betaine, dimethylglycine and glucose were measured on morning urine samples as the ratio to urine creatinine. Statistical determinants of the post-methionine load increase in homocysteine were identified in multiple linear regression models. Results Plasma betaine concentrations and urinary betaine excretions were significantly (p < 0.001) more variable in the subjects with diabetes compared with the controls. Dimethylglycine excretion (p = 0.00014) and plasma dimethylglycine concentrations (p = 0.039) were also more variable. In diabetes, plasma betaine was a significant negative determinant (p < 0.001) of the post-methionine load increase in homocysteine. However, it was not conclusive that this was different from the relationship in the controls. In the patients with diabetes, a strong relationship was found between urinary betaine excretion and urinary glucose excretion (but not with plasma glucose). Conclusions Both high and low plasma betaine concentrations, and high and low urinary betaine excretions, are more prevalent in diabetes. The availability of betaine affects the response in the methionine load test. The benefits of increasing betaine intake should be investigated. PMID:22510294

Therapeutic effect of Arctium lappa in Schistosoma haematobium associated kidney disturbance: biochemical and molecular effects.

PubMed

Koriem, Khaled M M; Idris, Zulzamri H; Haron, Hasniza F; Omar, Nurulhuda A; Lazain, Halita S

2016-12-01

Schistosoma haematobium ( S. haematobium ) infection has been found to be strongly associated with bladder cancer, which necessitates for discover of a natural new therapeutic agent. The aim of this study was to evaluate the therapeutic effect of Arctium lappa seed extract in S. haematobium associated kidney disturbance. Forty male albino mice were used and divided into four equal groups; group 1 control includes non-infected healthy mice, groups 2, 3 and 4 subcutaneous infected with S. haematobium cercariae. Groups 3 co-treated daily with oral dose of A. lappa seed extract (300 mg/kg, bwt) for 15 days in the same time of S. haematobium infection. Groups 4 post-treated daily for 15 days with oral dose of A. lappa seed extract (300 mg/kg, bwt) after 15 days of S. haematobium infection. The results obtained revealed that S. haematobium significantly decreased kidney weight and serum sodium, potassium and chloride, but increased urinary volume, urinary excretion of sodium, potassium and chloride, serum urea, creatinine and uric acid. Schistosoma haematobium also significantly decreased kidney superoxide dismutase, glutathione peroxidase and reduced glutathione levels while increased kidney lipid peroxidation level. Co- and post-treatment with A. lappa seed extract restore all the above parameters to approach the normal values. These results were supported with histopathological examinations. In conclusion, A. lappa seed extract has therapeutic effect in kidney disturbance caused by S. haematobium where co-treatment of A. lappa seed extract was more effective than post-treatment of the extract.

Identification of a sensitive urinary biomarker, selenium-binding protein 1, for early detection of acute kidney injury.

PubMed

Kim, Kyeong Seok; Yang, Hun Yong; Song, Hosup; Kang, Ye Rim; Kwon, JiHoon; An, JiHye; Son, Ji Yeon; Kwack, Seung Jun; Kim, Young-Mi; Bae, Ok-Nam; Ahn, Mee-Young; Lee, Jaewon; Yoon, Sungpil; Lee, Byung Mu; Kim, Hyung Sik

2017-01-01

Acute kidney injury (AKI) is associated with increased mortality rate in patients but clinically available biomarkers for disease detection are currently not available. Recently, a new biomarker, selenium-binding protein 1 (SBP1), was identified for detection of nephrotoxicity using proteomic analysis. The aim of this study was to assess the sensitivity of urinary SBP1 levels as an early detection of AKI using animal models such as cisplatin or ischemia/reperfusion (I/R). Sprague-Dawley rats were injected with cisplatin (6 mg/kg, once i.p.) and sacrificed at 1, 3, or 5 days after treatment. Ischemia was achieved by bilaterally occluding both kidneys with a microvascular clamp for 45 min and verified visually by a change in tissue color. After post-reperfusion, urine samples were collected at 9, 24, and 48 hr intervals. Urinary excretion of protein-based biomarkers was measured by Western blot analysis. In cisplatin-treated rats, mild histopathologic alterations were noted at day 1 which became severe at day 3. Blood urea nitrogen (BUN) and serum creatinine (SCr) levels were significantly increased at day 3. Levels of urinary excretion of SBP1, neutrophil gelatinase-associated lipocalin (NGAL), and a tissue inhibitor of metalloproteinase-1 (TIMP-1) were markedly elevated at day 3 and 5 following drug treatment. In the vehicle-treated I/R group, serum levels of BUN and SCr and AST activity were significantly increased compared to sham. Urinary excretion of SBP1 and NGAL rose markedly following I/R. The urinary levels of SBP1, NGAL, TIMP-1, and KIM-1 proteins excreted by AKI patients and normal subjects were compared. Among these proteins, a marked rise in SBP1 was observed in urine of patients with AKI compared to normal subjects. Based upon receiver-operator curves (ROC), SBP1 displayed a higher area under the curve (AUC) scores than levels of SCr, BUN, total protein, and glucose. In particular, SBP1 protein was readily detected in small amounts of urine without purification. Data thus indicate that urinary excretion of SBP1 may be useful as a reliable biomarker for early diagnosis of AKI in patients.

Comparison of two aquaretic drugs (niravoline and OPC-31260) in cirrhotic rats with ascites and water retention.

PubMed

Bosch-Marcé, M; Poo, J L; Jiménez, W; Bordas, N; Leivas, A; Morales-Ruiz, M; Muñoz, R M; Pérez, M; Arroyo, V; Rivera, F; Rodés, J

1999-04-01

kappa-Opioid receptor agonists (niravoline) or nonpeptide antidiuretic hormone (ADH) V2 receptor antagonists (OPC-31260) possess aquaretic activity in cirrhosis; however, there is no information concerning the effects induced by the chronic administration of these drugs under this condition. To compare the renal and hormonal effects induced by the long-term oral administration of niravoline, OPC-31260, or vehicle, urine volume, urinary osmolality, sodium excretion, and urinary excretion of aldosterone (ALD) and ADH were measured in basal conditions and for 10 days after the daily oral administration of niravoline, OPC-31260, or vehicle to cirrhotic rats with ascites and water retention. Creatinine clearance, serum osmolality, ADH mRNA expression, and systemic hemodynamics were also measured at the end of the study. Niravoline increased water excretion, peripheral resistance, serum osmolality, and sodium excretion and reduced creatinine clearance, ALD and ADH excretion, and mRNA expression of ADH. OPC-31260 also increased water metabolism and sodium excretion and reduced urinary ALD, although the aquaretic effect was only evident during the first 2 days, and no effects on serum osmolality, renal filtration, and systemic hemodynamics were observed. Therefore, both agents have aquaretic efficacy, but the beneficial therapeutic effects of the long-term oral administration of niravoline are more consistent than those of OPC-31260 in cirrhotic rats with ascites and water retention.

Effects of exercise on the urinary proteome.

PubMed

Kohler, Maxie; Schänzer, Wilhelm; Thevis, Mario

2015-01-01

Exercise-induced proteinuria has been observed and studied for more than a century. It was found that different sport disciplines alter the urinary proteome in different ways. Moderate-intensity exercise results in increased glomerular filtration, meaning that medium-sized proteins are excreted in higher amounts, while high-intensity exercise of short duration also increases the excretion of low molecular weight proteins as a result of tubular dysfunction. Exhaustive exercise may lead to the excretion of hemoglobin or myoglobin, which changes the urinary proteome considerably. Studies comparing protein maps of different sport types compared to a control group showed that quality and quantity of urinary proteins are interindividually different. In addition, urine samples collected before and after exercise exhibit substantially different protein patterns even from the same person. Therefore, further studies investigating the urinary proteome are desirable. As the variation of protein content and composition in urine are generally much higher than in other matrices, respective studies need to be well controlled and homogenous groups of volunteers should be chosen. In addition to the sport-related physiological and biochemical interest, exercise-induced protein changes also need to be considered for biomarker measurements from urine samples for kidney or other diseases.

Effect of cinnamon and turmeric on urinary oxalate excretion, plasma lipids, and plasma glucose in healthy subjects.

PubMed

Tang, Minghua; Larson-Meyer, D Enette; Liebman, Michael

2008-05-01

High oxalate intake resulting from consuming supplemental doses of cinnamon and turmeric may increase risk of hyperoxaluria, a significant risk factor for urolithiasis. This study assessed urinary oxalate excretion from supplemental doses of cinnamon and turmeric as well as changes in fasting plasma glucose, cholesterol, and triacylglycerol concentrations. Eleven healthy subjects, aged 21-38 y, participated in an 8-wk, randomly assigned, crossover study that involved the ingestion of supplemental doses of cinnamon and turmeric for 4-wk periods that provided 55 mg oxalate/d. Oxalate load tests, which entailed the ingestion of a 63-mg dose of oxalate from the test spices, were performed after each 4-wk experimental period and at the study onset with water only (control treatment). Fasting plasma glucose and lipid concentrations were also assessed at these time points. Compared with the cinnamon and control treatments, turmeric ingestion led to a significantly higher urinary oxalate excretion during the oxalate load tests. There were no significant changes in fasting plasma glucose or lipids in conjunction with the 4-wk periods of either cinnamon or turmeric supplementation. The percentage of oxalate that was water soluble differed markedly between cinnamon (6%) and turmeric (91%), which appeared to be the primary cause of the greater urinary oxalate excretion/oxalate absorption from turmeric. The consumption of supplemental doses of turmeric, but not cinnamon, can significantly increase urinary oxalate levels, thereby increasing risk of kidney stone formation in susceptible individuals.

Role of inward rectifier potassium channels in salivary gland function and sugar feeding of the fruit fly, Drosophila melanogaster

USDA-ARS?s Scientific Manuscript database

The arthropod salivary gland is of critical importance for horizontal transmission of pathogens, yet a detailed understanding of the ion conductance pathways responsible for saliva production and excretion is lacking. A superfamily of potassium ion channels, known as inward rectifying potassium (Ki...

Reversibility of increased intestinal permeability to 51Cr-EDTA in patients with gastrointestinal inflammatory diseases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jenkins, R.T.; Jones, D.B.; Goodacre, R.L.

1987-11-01

Intestinal permeability in adults with inflammatory gastrointestinal diseases was investigated by measuring the 24-h urinary excretion of orally administered /sup 51/Cr-EDTA. Eighty controls along with 100 patients with Crohn's disease, 46 patients with ulcerative colitis, 20 patients with gluten-sensitive enteropathy, and 18 patients with other diseases were studied. In controls, the median 24-h excretion was 1.34%/24 h of the oral dose. Patients with Crohn's disease (median 2.96%/24 h), ulcerative colitis (median 2.12%/24 h), and untreated gluten-sensitive enteropathy (median 3.56%/24 h) had significantly elevated urinary excretion of the probe compared to controls (p less than 0.0001). Increased 24-h urinary excretion ofmore » /sup 51/Cr-EDTA had a high association with intestinal inflammation (p less than 0.0001). Test specificity and sensitivity were 96% and 57%, respectively. A positive test has a 96% probability of correctly diagnosing the presence of intestinal inflammation, whereas a negative test has a 50% probability of predicting the absence of disease.« less

High Prolactin Excretion in Patients with Diabetes Mellitus and Impaired Renal Function.

PubMed

Triebel, Jakob; Moreno-Vega, Aura Ileana; Vázquez-Membrillo, Miguel; Nava, Gabriel; García-Franco, Renata; López-Star, Ellery; Baldivieso-Hurtado, Olivia; Ochoa, Daniel; Macotela, Yazmín; Bertsch, Thomas; Martinez de la Escalera, Gonzalo; Clapp, Carmen

2015-01-01

The metabolic clearance of prolactin (PRL) is partially executed by the kidney. Here, we investigate the urine excretion of PRL in patients with Diabetes Mellitus and renal impairment. Serum and urine samples were collected from male, mestizo patients in central Mexico employing a cross-sectional study design. Ninety-eight individuals had either no diabetes and normal renal function (control), diabetes and normal renal function, or diabetes with impaired renal function. PRL was determined by a chemiluminescent immunometric assay; protein, albumin, and creatinine were evaluated using quantitative colorimetric assays. The results were analyzed using ANOVA-testing. Patients with Diabetes Mellitus and renal impairment had significantly higher urine PRL levels than patients with Diabetes Mellitus and normal renal function and control patients. Higher urine PRL levels were associated with lower glomerular filtration rates, higher serum creatinine, and higher urinary albumin-to-creatinine ratios (UACR). Urine PRL levels correlated positively with UACR. Serum PRL levels were similar among groups. Patients with Diabetes Mellitus and impaired renal function demonstrate a high urinary PRL excretion. Urinary PRL excretion in the context of proteinuria could contribute to PRL dysregulation in renal impairment.

Hypertension increases urinary excretion of immunoglobulin G, ceruloplasmin and transferrin in normoalbuminuric patients with type 2 diabetes mellitus.

PubMed

Ohara, Nobumasa; Hanyu, Osamu; Hirayama, Satoshi; Nakagawa, Osamu; Aizawa, Yoshifusa; Ito, Seiki; Sone, Hirohito

2014-02-01

Increased urinary excretion of certain plasma proteins, such as immunoglobulin G (IgG), ceruloplasmin and transferrin, with different molecular radii of 55 Å or less and different isoelectric points have been reported to precede development of microalbuminuria in patients who have diabetes mellitus with hypertension. We examined how hypertension affects these urinary proteins in a diabetic state. Excretion of IgG, ceruloplasmin, transferrin, albumin, α2-macroglobulin with a large molecular radius of 88 Å and N-acetylglucosaminidase in first-morning urine samples were measured in normoalbuminuric patients (urinary albumin-to-creatinine ratio < 15 mg/g) with hypertension and nondiabetes mellitus (group hypertension, n = 32), type 2 diabetes mellitus and normotension (group diabetes mellitus, n = 52) and type 2 diabetes mellitus and hypertension (group Both, n =45), and in age-matched controls (n = 72). Urinary IgG, ceruloplasmin, transferrin, albumin and N-acetylglucosaminidase and estimated glomerular filtration rate (eGFR) were significantly elevated in groups diabetes mellitus and Both compared with controls. Furthermore, urinary IgG, ceruloplasmin and transferrin in group Both were significantly higher than those in group diabetes mellitus. These exhibited a positive and relatively strong association with eGFR compared with controls. No significant difference in urinary albumin or N-acetylglucosaminidase was found between the two diabetic groups. In contrast, group hypertension had elevated urinary transferrin without any changes in the other compounds. Urinary α2-macroglobulin did not differ among the four groups. These findings suggest that normoalbuminuric diabetic patients without hypertension have both glomerular hemodynamic changes such as increased intraglomerular hydraulic pressure and altered proximal tubules, and that hypertension increases intraglomerular hydraulic pressure. Increased urinary IgG, ceruloplasmin and transferrin may reflect an increase in intraglomerular hydraulic pressure.

Potassium measurements and risk of type 2 diabetes: a dose-response meta-analysis of prospective cohort studies

PubMed Central

Peng, Yang; Zhong, Guo-Chao; Mi, Qiao; Li, Kejia; Wang, Ao; Li, Ling; Liu, Hua; Yang, Gangyi

2017-01-01

Objective To clarify the relationship between serum, dietary, and urinary potassium and the risk of type 2 diabetes mellitus (T2DM). Materials and Methods We searched PubMed and EMBASE through January 6, 2017 for studies reporting risk estimates on the association of potassium measurements and the risk of T2DM. The summary risk estimates were obtained through a random-effects model. Dose-response analysis was conducted. Results Eight studies involving 5,053 cases and 119,993 individuals were included. A trend toward significance was found in the highest versus lowest meta-analysis on serum potassium and T2DM risk (RR = 0.79; 95% CI 0.60–1.04); moreover, the RR per 1 mmol/L increase in serum potassium was 0.83 (95% CI 0.73–0.95). A non-significant association of dietary potassium and T2DM risk was detected (RR for the highest versus lowest category: 0.93; 95% CI 0.81–1.06; RR for every 1000mg increase per day: 1.00, 95% CI 0.96–1.05). A similar non-significant association was found for urinary potassium and T2DM risk (RR for the highest versus lowest category: 0.83; 95% CI 0.39–1.75; RR per 10 mmol increase: 1.00; 95% CI 0.95–1.05). Evidence of a linear association between serum, dietary, and urinary potassium and the risk of T2DM was found (all Pnon-linearity > 0.05). Conclusions Low serum potassium increases the risk of T2DM in a linear dose-response manner; nevertheless, neither dietary potassium nor urinary potassium shows any association with the risk of T2DM. However, these findings should be interpreted with caution due to limited studies. PMID:29246005

Effect of endovascular treatment on nitric oxide and renal function in Takayasu's arteritis with renovascular hypertension.

PubMed

Parildar, Zuhal; Gulter, Ceyda; Parildar, Mustafa; Oran, Ismail; Erdener, Dilek; Memis, Ahmet

2002-01-01

Renal involvement in Takayasu's arteritis (TA) effects the disease outcome and endovascular treatment is an effective treatment of choice. We investigated nitric oxide (NO) levels and the effect of endovascular treatment in renovascular hypertensive TA patients. In five hypertensive patients with renal artery stenosis due to TA, serum creatinine, nitrite, nitrate; urinary microalbumin, nitrite, nitrate measurements and blood pressures were recorded at entry and after 24 h and 6 weeks of endovascular treatment. Serum NO levels were higher in patients than controls (p = 0.008). Serum and urine NO levels increased 24 h after the treatment and decreased after 6 weeks (p = 0.015; p = 0.01, respectively). After the treatment blood pressures decreased. Urinary microalbumin excretions increased after the intervention (p = 0.02) and returned to normal in patients 1 and 4, and decreased in the others. There were no significant differences in estimated glomerular filtration rate (EGFR), serum creatinine, urinary sodium and potassium levels. Increased NO secretion in these patients may contribute to improve the prognosis of renal function through its vasodilator and antiproliferative activities possibly by counterbalancing the excessive vasoconstrictor actions. Endovascular treatment causes a dilatation-induced shear stress that may be responsible for the increased NO release, which in turn leads to the rapid hypotensive response. Copyright 2002 S. Karger AG, Basel

Effect of acute hyperinsulinemia on magnesium homeostasis in humans.

PubMed

Xu, Li Hao Richie; Maalouf, Naim M

2017-02-01

Insulin may influence magnesium homeostasis through multiple mechanisms. Acutely, it stimulates the shift of magnesium from plasma into red blood cells and platelets, and in vitro, it stimulates the activity of the TRPM6 channel, a key regulator of renal magnesium reabsorption. We investigated the impact of hyperinsulinemia on magnesium handling in participants with a wide range of insulin sensitivity. Forty-seven participants were recruited, including 34 nondiabetic controls and 13 with type 2 diabetes mellitus. After stabilization under fixed metabolic diet, participants underwent hyperinsulinemic-euglycemic clamp. Serum and urine samples were collected before and during hyperinsulinemia. Change in serum magnesium, urinary magnesium to creatinine (Mg 2 + :Cr) ratio, fractional excretion of urinary magnesium (FEMg 2 + ), and estimated transcellular shift of magnesium were compared before and during hyperinsulinemia. Hyperinsulinemia led to a small but statistically significant decrease in serum magnesium, and to a shift of magnesium into the intracellular compartment. Hyperinsulinemia did not significantly alter urinary magnesium to creatinine ratio or fractional excretion of urinary magnesium in the overall population, although a small but statistically significant decline in these parameters occurred in participants with diabetes. There was no significant correlation between change in fractional excretion of urinary magnesium and body mass index or insulin sensitivity measured as glucose disposal rate. In human participants, acute hyperinsulinemia stimulates the shift of magnesium into cells with minimal alteration in renal magnesium reabsorption, except in diabetic patients who experienced a small decline in fractional excretion of urinary magnesium. The magnitude of magnesium shift into the intracellular compartment in response to insulin does not correlate with that of insulin-stimulated glucose entry into cells. Copyright © 2016 John Wiley & Sons, Ltd.

Urinary oxalate to creatinine ratios in healthy Turkish schoolchildren

PubMed Central

Dursun, Ismail; Çelik, İlknur; Poyrazoglu, Hakan M.; Tanrıkulu, Esen; Sahin, Habibe; Yılmaz, Kenan; Öztürk, Ahmet; Yel, Sibel; Gündüz, Zübeyde; Düşünsel, Ruhan

2017-01-01

Abstract Aim: we aimed to establish reference values for urinary oxalate to creatinine ratios in healthy children aged 6–15 years and to investigate the relationship between their nutritional habits and oxalate excretion. Materials and methods: Random urine specimens from 953 healthy children aged 6–15 years were obtained and analyzed for oxalate and creatinine. Additionally, a 24-h dietary recall form was prepared and given to them. The ingredient composition of the diet was calculated. The children were divided into three groups according to age: Group I (69 years, n = 353), Group II (10–12 years, n = 335), and Group III (13–15 years, n = 265). Results: The 95th percentile of the oxalate to creatinine ratio for subjects aged 6–9, 10–12, and 13–15 years were 0.048, 0.042, and 0.042 mg/mg, respectively. The oxalate to creatinine ratio was significantly higher in Group 1 than in Group 2 and Group 3. Urinary oxalate excretion was positively correlated with increased protein intake and negatively correlated with age. A significant positive correlation was determined between urinary oxalate excretion and the proline, serine, protein, and glycine content of diet. Dietary proline intake showed a positive correlation with the urine oxalate to creatinine ratio and was found to be an independent predictor for urinary oxalate. Conclusions: These data lend support to the idea that every country should have its own normal reference values to determine the underlying metabolic risk factor for kidney stone disease since regional variation in the dietary intake of proteins and other nutrients can affect normal urinary excretion of oxalate. PMID:27846788

Estimating 24-Hour Urinary Sodium Excretion From Casual Urinary Sodium Concentrations in Western Populations

PubMed Central

Brown, Ian J.; Dyer, Alan R.; Chan, Queenie; Cogswell, Mary E.; Ueshima, Hirotsugu; Stamler, Jeremiah; Elliott, Paul

2013-01-01

High intakes of dietary sodium are associated with elevated blood pressure levels and an increased risk of cardiovascular disease. National and international guidelines recommend reduced sodium intake in the general population, which necessitates population-wide surveillance. We assessed the utility of casual (spot) urine specimens in estimating 24-hour urinary sodium excretion as a marker of sodium intake in the International Cooperative Study on Salt, Other Factors, and Blood Pressure. There were 5,693 participants recruited in 1984–1987 at the ages of 20–59 years from 29 North American and European samples. Participants were randomly assigned to test or validation data sets. Equations derived from casual urinary sodium concentration and other variables in the test data were applied to the validation data set. Correlations between observed and estimated 24-hour sodium excretion were 0.50 for individual men and 0.51 for individual women; the values were 0.79 and 0.71, respectively, for population samples. Bias in mean values (observed minus estimated) was small; for men and women, the values were −1.6 mmol per 24 hours and 2.3 mmol per 24 hours, respectively, at the individual level and −1.8 mmol per 24 hours and 2.2 mmol per 24 hours, respectively, at the population level. Proportions of individuals with urinary 24-hour sodium excretion above the recommended levels were slightly overestimated by the models. Casual urine specimens may be a useful, low-burden, low-cost alternative to 24-hour urine collections for estimation of population sodium intakes; ongoing calibration with study-specific 24-hour urinary collections is recommended to increase validity. PMID:23673246

Neurogenic regulation of proximal bicarbonate and chloride reabsorption.

PubMed

Cogan, M G

1986-01-01

Although a change in renal nerve activity is known to alter proximal reabsorption, it is unclear whether reabsorption of NaHCO3 or NaCl or both are affected. Sprague-Dawley rats (n = 10) were studied using free-flow micropuncture techniques during euvolemia and following acute ipsilateral denervation. Glomerular filtration rate and single nephron glomerular filtration rate were stable. Absolute proximal bicarbonate reabsorption fell following denervation (933 +/- 40 to 817 +/- 30 pmol/min) with a parallel reduction in chloride reabsorption (1,643 +/- 116 to 1,341 +/- 129 peq/min). Urinary sodium, potassium, bicarbonate, and chloride excretion all increased significantly. To further assess the physiological significance of neurogenic modulation of proximal transport, other rats (n = 6) were subjected to acute unilateral nephrectomy (AUN). There is evidence that AUN induces a contralateral natriuresis (renorenal reflex) at least partially by causing inhibition of efferent renal nerve traffic. AUN caused significant changes in proximal NaHCO3 and NaCl reabsorption as well as in whole kidney electrolyte excretion in the same pattern as had denervation. Prior denervation of the remaining kidney prevented the proximal and whole kidney response to AUN (n = 6). In conclusion, depression of renal nerve activity inhibits both NaHCO3 and NaCl reabsorption in the rat superficial proximal convoluted tubule. The data are consistent with the hypothesis that changes in renal nerve activity modify whole kidney electrolyte excretion under physiological conditions at least partially by regulating proximal transport.

Effect of paricalcitol on renin and albuminuria in non-diabetic stage III-IV chronic kidney disease: a randomized placebo-controlled trial

PubMed Central

2013-01-01

Background Vitamin D receptor activators reduce albuminuria, and may improve survival in chronic kidney disease (CKD). Animal studies suggest that these pleiotropic effects of vitamin D may be mediated by suppression of renin. However, randomized trials in humans have yet to establish this relationship. Methods In a randomized, placebo-controlled, double-blinded crossover study, the effect of oral paricalcitol (2 μg/day) was investigated in 26 patients with non-diabetic, albuminuric stage III-IV CKD. After treatment, plasma concentrations of renin (PRC), angiotensin II (AngII) and aldosterone (Aldo) were measured. GFR was determined by 51Cr-EDTA clearance. Assessment of renal NO dependency was performed by infusion of NG-monomethyl-L-arginine (L-NMMA). Albumin excretion rate (AER) was analyzed in 24-h urine and during 51Cr-EDTA clearance. Results Paricalcitol did not alter plasma levels of renin, AngII, Aldo, or urinary excretion of sodium and potassium. A modest reduction of borderline significance was observed in AER, and paricalcitol abrogated the albuminuric response to L-NMMA. Conclusions In this randomized, placebo-controlled trial paricalcitol only marginally decreased AER and did not alter circulating levels of renin, AngII or Aldo. The abrogation of the rise in albumin excretion by paricalcitol during NOS blockade may indicate that favourable modulation of renal NO dependency could be involved in mediating reno-protection and survival benefits in CKD. Trial registration ClinicalTrials.gov identifier: NCT01136564 PMID:23889806

Hypophosphatemic rickets with hypocalciuria following long-term treatment with aluminum-containing antacid.

PubMed

Foldes, J; Balena, R; Ho, A; Parfitt, A M; Kleerekoper, M

1991-01-01

We present what we believe is the first case of rickets following prolonged treatment with aluminum containing antacids that bind phosphate, in an 18-year-old mentally retarded boy with cerebral palsy and spastic quadriplegia. As expected, serum calcitriol was increased and urinary phosphate excretion was very low. However, in contrast to all published cases of antacid induced hypophosphatemic osteomalacia in adults, despite a substantial increase in bone resorption reflected by urinary total hydroxyproline excretion, urinary calcium excretion was low rather than high, and significant hypocalcemia occurred after antacids were ceased and a phosphate salt administered. We suggest that the skeleton was so under-mineralized because of growth during prolonged phosphate deficiency, possibly augmented by anticonvulsant administration and immobilization, that increased bone resorption did not release enough calcium to cause hypercalciuria, or to prevent hypocalcemia during resumption of normal mineralization.

THE METABOLISM OF SILICON IN THE RAT AND ITS RELATION TO THE FORMATION OF ARTIFICIAL SILICEOUS CALCULI

PubMed Central

Keeler, Richard F.; Lovelace, Stuart A.

1959-01-01

The urinary excretion of silicon in the rat was found to be enhanced beyond normal levels by the administration of various chemical forms of silicon. The excretion was enhanced to a much greater degree by the administration of ethyl silicate than by magnesium trisilicate, sodium metasilicate, or water glass. The tolerance level of rats to sustained daily doses of ethyl silicate fed via stomach tube was approximately 15 to 30 mg. of silicon per rat per day. Urinary silicon excretion was found to be a straight line function of the concentration of ethyl silicate administered, via stomach tube, with approximately 18 per cent of the administered silicon appearing in the urine at all levels tested. Using sustained dietary additions of ethyl silicate as a means of enhancing urine silicon levels, artificial siliceous urinary calculi were consistently produced on zinc pellets implanted in the bladders of rats. PMID:13654631

Genetic variation underlying renal uric acid excretion in Hispanic children: the Viva La Familia Study.

PubMed

Chittoor, Geetha; Haack, Karin; Mehta, Nitesh R; Laston, Sandra; Cole, Shelley A; Comuzzie, Anthony G; Butte, Nancy F; Voruganti, V Saroja

2017-01-17

Reduced renal excretion of uric acid plays a significant role in the development of hyperuricemia and gout in adults. Hyperuricemia has been associated with chronic kidney disease and cardiovascular disease in children and adults. There are limited genome-wide association studies associating genetic polymorphisms with renal urate excretion measures. Therefore, we investigated the genetic factors that influence the excretion of uric acid and related indices in 768 Hispanic children of the Viva La Familia Study. We performed a genome-wide association analysis for 24-h urinary excretion measures such as urinary uric acid/urinary creatinine ratio, uric acid clearance, fractional excretion of uric acid, and glomerular load of uric acid in SOLAR, while accounting for non-independence among family members. All renal urate excretion measures were significantly heritable (p <2 × 10 -6 ) and ranged from 0.41 to 0.74. Empirical threshold for genome-wide significance was set at p <1 × 10 -7 . We observed a strong association (p < 8 × 10 -8 ) of uric acid clearance with a single nucleotide polymorphism (SNP) in zinc finger protein 446 (ZNF446) (rs2033711 (A/G), MAF: 0.30). The minor allele (G) was associated with increased uric acid clearance. Also, we found suggestive associations of uric acid clearance with SNPs in ZNF324, ZNF584, and ZNF132 (in a 72 kb region of 19q13; p <1 × 10 -6 , MAFs: 0.28-0.31). For the first time, we showed the importance of 19q13 region in the regulation of renal urate excretion in Hispanic children. Our findings indicate differences in inherent genetic architecture and shared environmental risk factors between our cohort and other pediatric and adult populations.

Excess dietary sodium and inadequate potassium intake in Italy: results of the MINISAL study.

PubMed

Donfrancesco, C; Ippolito, R; Lo Noce, C; Palmieri, L; Iacone, R; Russo, O; Vanuzzo, D; Galletti, F; Galeone, D; Giampaoli, S; Strazzullo, P

2013-09-01

As excess sodium and inadequate potassium intake are causally related to hypertension and cardiovascular disease, the MINISAL-GIRCSI Program aimed to provide reliable estimates of dietary sodium and potassium intake in representative samples of the Italian population. Random samples of adult population were collected from 12 Italian regions, including 1168 men and 1112 women aged 35-79 yrs. Electrolyte intake was estimated from 24 hour urine collections and creatinine was measured to estimate the accuracy of the collection. Anthropometric indices were measured with standardised procedures. The average sodium excretion was 189 mmol (or 10.9 g of salt/day) among men and 147 mmol (or 8.5 g) among women (range 27-472 and 36-471 mmol, respectively). Ninety-seven % of men and 87% of women had a consumption higher than the WHO recommended target of 5g/day. The 24 h average potassium excretion was 63 and 55 mmol, respectively (range 17-171 and 20-126 mmol), 96% of men and 99% of women having an intake lower than 100 mmol/day (European and American guideline recommendation). The mean sodium/potassium ratio was 3.1 and 2.8 respectively, i.e. over threefold greater than the desirable level of 0.85. The highest sodium intake was observed in Southern regions. Sodium and potassium excretion were both progressively higher the higher the BMI (p < 0.0001). These MINISAL preliminary results indicate that in all the Italian regions thus far surveyed dietary sodium intake was largely higher and potassium intake lower than the recommended intakes. They also highlight the critical association between overweight and excess salt intake. Copyright © 2012 Elsevier B.V. All rights reserved.

Urinary Excretion of Tetrodotoxin Modeled in a Porcine Renal Proximal Tubule Epithelial Cell Line, LLC-PK₁.

PubMed

Matsumoto, Takuya; Ishizaki, Yui; Mochizuki, Keika; Aoyagi, Mitsuru; Mitoma, Yoshiharu; Ishizaki, Shoichiro; Nagashima, Yuji

2017-07-17

This study examined the urinary excretion of tetrodotoxin (TTX) modeled in a porcine renal proximal tubule epithelial cell line, LLC-PK₁. Time course profiles of TTX excretion and reabsorption across the cell monolayers at 37 °C showed that the amount of TTX transported increased linearly for 60 min. However, at 4 °C, the amount of TTX transported was approximately 20% of the value at 37 °C. These results indicate that TTX transport is both a transcellular and carrier-mediated process. Using a transport inhibition assay in which cell monolayers were incubated with 50 µM TTX and 5 mM of a transport inhibitor at 37 °C for 30 min, urinary excretion was significantly reduced by probenecid, tetraethylammonium (TEA), l-carnitine, and cimetidine, slightly reduced by p -aminohippuric acid (PAH), and unaffected by 1-methyl-4-phenylpyridinium (MPP+), oxaliplatin, and cefalexin. Renal reabsorption was significantly reduced by PAH, but was unaffected by probenecid, TEA and l-carnitine. These findings indicate that TTX is primarily excreted by organic cation transporters (OCTs) and organic cation/carnitine transporters (OCTNs), partially transported by organic anion transporters (OATs) and multidrug resistance-associated proteins (MRPs), and negligibly transported by multidrug and toxic compound extrusion transporters (MATEs).

Effect of Docosahexaenoic Acid Ingestion on Temporal Change in Urinary Excretion of Mercapturic Acid in ODS Rats.

PubMed

Sekine, Seiji; Kubo, Kazuhiro; Tadokoro, Tadahiro; Saito, Morio

2007-11-01

We hypothesized a suppressive mechanism for docosahexaenoic acid (22:6n-3; DHA)-induced tissue lipid peroxidation in which the degradation products, especially aldehydic compounds, are conjugated with glutathione through catalysis by glutathione S-transferases, and then excreted into urine as mercapturic acids. In the present study, ascorbic acid-requiring ODS rats were fed a diet containing DHA (3.6% of total energy) for 31 days. Lipid peroxides including degradation products and their scavengers in the liver and kidney were determined, and the temporal change in the urinary excretion of mercapturic acids was also measured. The activity of aldehyde dehydrogenase, which catalyzes the oxidation and detoxification of aldehydes, tended to be higher in the liver of DHA-fed rats. The levels of lipid peroxides as measured by thiobarbituric acid-reactive substances and aldehydic compounds were higher and that of alpha-tocopherol was lower in the liver, and the pattern of temporal changes in the urinary excretion of mercapturic acids was also different between the n-6 linoleic acid and DHA-fed rats. Accordingly, we presume from these results that after dietary DHA-induced lipid peroxidation, a proportion of the lipid peroxidation-derived aldehydic degradation products is excreted into urine as mercapturic acids.

Effect of Docosahexaenoic Acid Ingestion on Temporal Change in Urinary Excretion of Mercapturic Acid in ODS Rats

PubMed Central

Sekine, Seiji; Kubo, Kazuhiro; Tadokoro, Tadahiro; Saito, Morio

2007-01-01

We hypothesized a suppressive mechanism for docosahexaenoic acid (22:6n-3; DHA)-induced tissue lipid peroxidation in which the degradation products, especially aldehydic compounds, are conjugated with glutathione through catalysis by glutathione S-transferases, and then excreted into urine as mercapturic acids. In the present study, ascorbic acid-requiring ODS rats were fed a diet containing DHA (3.6% of total energy) for 31 days. Lipid peroxides including degradation products and their scavengers in the liver and kidney were determined, and the temporal change in the urinary excretion of mercapturic acids was also measured. The activity of aldehyde dehydrogenase, which catalyzes the oxidation and detoxification of aldehydes, tended to be higher in the liver of DHA-fed rats. The levels of lipid peroxides as measured by thiobarbituric acid-reactive substances and aldehydic compounds were higher and that of α-tocopherol was lower in the liver, and the pattern of temporal changes in the urinary excretion of mercapturic acids was also different between the n-6 linoleic acid and DHA-fed rats. Accordingly, we presume from these results that after dietary DHA-induced lipid peroxidation, a proportion of the lipid peroxidation-derived aldehydic degradation products is excreted into urine as mercapturic acids. PMID:18299714

[Diagnostic value of radom spot albuminuria to creatinine ratio in women with preeclampsia].

PubMed

Gao, Yun-fei; Huang, Qi-tao; Zhong, Mei; Wang, Yan; Wang, Wei; Wang, Zhi-jian; Leng, Ling-zhi; Yu, Yan-hong

2012-03-01

To investigate the correlation between spot albuminuria to creatinine ratio (ACR) and 24 h urinary protein excretion in women with preeclampsia and determine the optimal cut-off values of spot ACR in mild preeclampsia and severe preeclampsia. Twenty-eight women with mild preeclampsia and 22 with severe preeclampsia at Nanfang Hospital, Southern Medical University between October 2010 and June 2011 were recruited. Maternal serum cystatin, uric acid, urea nitrogen, creatinine and albumin levels were collected and analyzed. Twenty-four hours urinary protein excretion was measured with immunoturbidimetric assay and ACR with automatic analyzer DCA2000. The correlation between ACR and 24 hours urinary protein excretion was explored. And the optimal cut-off values of the spot ACR for mild and severe preeclampsia were determined with receiver operating characteristic curve. (1) Maternal serum biochemical parameters: uric acid levels in mild and severe preeclampsia were (359 ± 114) µmol/L and (450 ± 132) µmol/L, while cystatin levels were (1.3 ± 0.3) mg/L and (1.6 ± 0.5) mg/L respectively. The differences were statistically significant (P < 0.05). Serum urea nitrogen, creatinine and albumin in mild preeclampsia were (3.6 ± 1.6) mmol/L, (52 ± 38) µmol/L and (33 ± 3) g/L, while in severe preeclampsia were (6.2 ± 3.1) mmol/L, (78 ± 59) µmol/L and (29 ± 6) g/L respectively. There were no statistical significant differences (P > 0.05). (2) Twenty-four hours urinary protein excretion and ACR: 24 hours urinary protein levels in mild and severe preeclampsia was (700 ± 160) mg and (4800 ± 2200) mg (P < 0.05). ACR in mild and severe preeclampsia was (72.7 ± 12.4) mg/mmol and (401 ± 245) mg/mmol respectively (P < 0.05). (3) There was a strong correlation between the spot ACR and 24 hours urine protein excretion (r = 0.938; P < 0.05). (4) The optimal spot ACR cut-off point for the diagnosis of preeclampsia: the optimal spot ACR cut-off point was 22.8 mg/mmol for 300 mg/24 hours of protein excretion in mild preeclampsia, the area under curve was 0.956, with a sensitivity, specificity of 82.4%, 99.4% respectively. And the optimal spot ACR cut-off point was 155.6 mol for 2000 mg/24 hours of protein excretion in severe preeclampsia, the area under curve was 0.956, with a sensitivity, specificity of 88.6%, 91.3% respectively. Compared with 24 hours urinary protein excretion, the spot ACR may be a simple, convenient and accurate indicator of early diagnosis of preeclampsia. Spot ACR may be used as a replacement for 24 hours urine protein excretion in assessment of preeclampsia. The optimal spot ACR cut off points were 22.8 mg/mmol for mild preeclampsia and 155.6 mg/mmol for severe preeclampsia.

Neurohumoral mechanism in the natriuretic action of intracerebroventricular administration of renin.

PubMed

Zavala, Lida; Barbella, Yarisma; Israel, Anita

2004-03-01

Intracerebroventricular (i.v.t.) administration of renin (R) decreases urinary volume and increases urinary sodium excretion. We investigated whether i.v.t.-R-induced natriuresis could be associated with the release of atrial natriuretic peptide (ANP), its interaction with renal ANP-A receptors (ANPR-A) and the subsequent increase of urinary cyclic 3-5 guanosine monophosphate (cGMP). In i.v.t. cannulated rats, the left carotid artery was catheterised with PE-50 tubing for blood collection, renin was injected i.v.t. and arterial blood samples were collected at 0, 2, 5, 10 and 15 minutes of injection, and urinary sodium and cGMP excretion at 1-, 3- and 6-hour periods of urine collection. Plasma ANP levels and urinary cGMP were determined by radioimmunoassay, and each urine sample was analysed for sodium concentration using a flame photometer. Our results demonstrate that i.v.t.-R administration increases plasma ANP levels after two minutes of injection and urinary cGMP concentration at 1-, 3- and 6 hour period of urine collection. The natriuretic action induced by i.v.t.-R was blunted by peripheral administration of anantin, an ANPR-A antagonist. We assessed the role of brain angiotensin II (Ang II) AT1-receptors on the i.v.t.-induced antidiuresis, natriuresis and cGMP urinary excretion, the last as an indirect index of ANP secretion. Blockade of brain Ang II AT1-receptors with losartan (LOS; 120 microg/3 microl, i.v.t.), inhibited the antidiuretic action and blocked the increased urinary sodium and cGMP excretion induced by i.v.t.-R (7.14 mGU/5 microl). The increase in urinary cGMP was independent of nitric oxide synthase stimulation, since L-NAME pre-treatment did not alter the renal actions induced by i.v.t.-R. Our results suggest that there is a link between the brain and the kidney. The activation of brain angiotensinergic neurons and stimulation of AT1- receptors may stimulate the release of ANP to the circulation. The released ANP circulates to the kidneys where it acts through renal ANPR-As and the consequent increase in cGMP to produce natriuresis.

Bifidobacterium animalis subsp. lactis decreases urinary oxalate excretion in a mouse model of primary hyperoxaluria

PubMed Central

Whittamore, Jonathan M.; Hatch, Marguerite

2015-01-01

Hyperoxaluria significantly increases the risk of calcium oxalate kidney stone formation. Since several bacteria have been shown to metabolize oxalate in vitro, including probiotic bifidobacteria, we focused on the efficiency and possible mechanisms by which bifidobacteria can infuence oxalate handling in vivo, especially in the intestines, and compared these results with the reported effects of Oxalobacter formigenes. Bifidobacterium animalis subsp. lactis DSM 10140 and B. adolescentis ATCC 15703 were administered to wild-type (WT) mice and to mice defcient in the hepatic enzyme alanine-glyoxylate aminotransferase (Agxt−/−, a mouse model of Primary Hyperoxaluria) that were fed an oxalate-supplemented diet. The administration of B. animalis subsp. lactis led to a significant decrease in urinary oxalate excretion in WT and Agxt−/− mice when compared to treatment with B. adolescent-is. Detection of B. animalis subsp. lactis in feces revealed that 3 weeks after oral gavage with the bacteria 64 % of WT mice, but only 37 % of Agxt−/− mice were colonized. Examining intestinal oxalate fuxes showed there were no significant changes to net oxalate secretion in colonized animals and were therefore not associated with the changes in urinary oxalate excretion. These results indicate that colonization with B. animalis subsp. lactis decreased urinary oxalate excretion by degrading dietary oxalate thus limiting its absorption across the intestine but it did not promote enteric oxalate excretion as reported for O. formigenes. Preventive or therapeutic administration of B. animalis subsp. lactis appears to have some potential to beneficially infuence dietary hyperoxaluria in mice. PMID:25269440

Substituting milk for apple juice does not increase kidney stone risk in most normocalciuric adults who form calcium oxalate stones.

PubMed

Massey, L K; Kynast-Gales, S A

1998-03-01

Increasing intake of dietary calcium from less than 400 mg to 800 mg daily may decrease the absorption of dietary oxalate, which in turn would decrease urinary oxalate excretion. The effect of substituting milk for apple juice on urine composition and risk of calcium oxalate precipitability was studied. Twenty-one normocalciuric adults with a history of at least 1 calcium oxalate stone and urinary oxalate excretion exceeding 275 micromol/day on their self-selected diet. Randomized crossover trial. Each participant consumed two moderate-oxalate (2,011 micromol/day) study diets, which were identical except that one contained 360 mL milk and the other contained 540 mL apple juice as the beverage with meals. Four days free-living then 2 days in the metabolic unit of a university nutrition department. Tiselius risk index for calcium oxalate precipitability calculated from urine composition. Paired t tests. Twenty-four hour urinary oxalate excretion was 18% lower (P<.0001) on the milk diet vs the juice diet: 423 vs 514 micromol, respectively. Calcium excretion was 17% higher (P<.05) on the milk vs juice diet: 4.7 vs 3.9 mmol, respectively. Urinary magnesium and citrate excretion, volume, and Tiselius risk index did not differ between diets. Substituting 360 mL milk daily for apple juice with meals in a diet containing moderate amounts of dietary oxalate from whole grains, legumes, fruits, and vegetables does not increase the risk index of calcium oxalate precipitability in most normocalciuric adults who form stones.

Metabolism of gonadotropins: comparisons of the primary structures of the human pituitary and urinary LH beta cores and the chimpanzee CG beta core demonstrate universality of core production.

PubMed

Birken, S; Gawinowicz, M A; Maydelman, Y; Milgrom, Y

2001-10-01

The gonadotropins are a family of closely related heterodimeric glycoprotein hormones homologous in structure to disulfide-knot growth factors. Metabolic proteolytic processing in vivo of this disulfide cross-linked region results in urinary excretion of a residual highly stable core structure. The primary structure of the pituitary form of the hLH beta core was reported earlier, but it has proved difficult to isolate the urinary core, although antibodies to the pituitary core demonstrated its presence. By conventional and immunoaffinity methods, the urinary core has been isolated and its structure determined by both chemical and mass spectrometric methods. The urinary hLH beta core is the same as the pituitary-extracted hLH beta core, beta 6-40 disulfide bridged to beta 55-93, except that the pituitary core is more heterogeneous containing also beta 49-93. These findings imply a dual origin of urinary cores, both directly from a secreting tissue and by kidney processing of circulating hormone. We also found that pregnant chimpanzees excrete a CG beta core with a primary structure identical to that of the human CG beta core of pregnancy. In conclusion, gonadotropin core generation and urinary excretion of nearly identical gonadotropin metabolites is common among primates. Although possible biological functions of these core fragments remain unproven, they have diagnostic utility because of their stability and abundance.

Potassium bicarbonate supplementation lowers bone turnover and calcium excretion in older men and women a randomized dose-finding trial

USDA-ARS?s Scientific Manuscript database

The acid load accompanying modern diets may have adverse effects on bone and muscle metabolism. Treatment with alkaline salts of potassium can neutralize the acid load, but the optimal amount of alkali is not established. Our objective was to determine the effectiveness of two doses of potassium bic...

Daily urinary urea excretion to guide intermittent hemodialysis weaning in critically ill patients.

PubMed

Aniort, Julien; Ait Hssain, Ali; Pereira, Bruno; Coupez, Elisabeth; Pioche, Pierre Antoine; Leroy, Christophe; Heng, Anne Elisabeth; Souweine, Bertrand; Lautrette, Alexandre

2016-02-19

There are no easily available markers of renal recovery to guide intermittent hemodialysis (IHD) weaning. The aim of this study was to identify markers for IHD weaning in critically ill patients with acute kidney injury (AKI). We performed a retrospective single-center cohort study of patients treated with IHD for at least 7 days and four dialysis sessions for AKI between 2006 and 2011 in an intensive care unit (ICU) of a French university hospital. Blood and urinary markers were recorded on the day of the last IHD in the ICU for unweaned patients and 2 days after the last IHD for weaned patients. Factors associated with IHD weaning were identified by multiple logistic regression. The areas under the receiver operating characteristic curve (AUROC) and the characteristics of the best diagnostic thresholds were compared. Sixty-seven patients were analyzed, including thirty-seven IHD-weaned patients. Urine output [odds ratio (OR) 1.59, 95% confidence interval (CI) 1.20-2.10 (per ml/kg/24 h increase); P = 0.01] and urinary urea concentration [OR 1.29, 95% CI 1.01-1.64 (per 10 mmol/L increase); P = 0.04] were both associated with IHD weaning. The optimal diagnostic thresholds for IHD weaning were urine output greater than 8.5 ml/kg/24 h, urinary urea concentration greater than 148 mmol/L, and daily urea excretion greater than 1.35 mmol/kg/24 h, with accuracy of 82.1%, 76.1%, and 92.5% (P = 0.03), respectively. The AUROC of daily urinary urea excretion (0.96) was greater than the AUROC of urine output (0.86) or the AUROC of urinary urea concentration (0.83) (P < 0.001). A daily urinary urea excretion greater than 1.35 mmol/kg/24 h was found to be the best marker for weaning ICU patients with AKI from IHD.

Management of hyperkalaemia.

PubMed

Maxwell, A P; Linden, K; O'Donnell, S; Hamilton, P K; McVeigh, G E

2013-01-01

Hyperkalaemia, an elevated extracellular fluid potassium concentration, is a common electrolyte disorder and is present in 1-10% of hospitalised patients. Elevated serum potassium concentrations are usually asymptomatic but may be associated with electrocardiogram (ECG) changes. Hyperkalaemia occasionally leads to life-threatening cardiac arrhythmias. Prompt recognition of this disorder, patient risk management and administration of appropriate treatment can prevent serious cardiac complications of hyperkalaemia. Further assessment of the underlying basis for hyperkalaemia usually reveals a problem with renal potassium excretion (rather than transcellular shift of potassium or excess potassium intake). Reduced potassium excretion is typically associated with decreased potassium secretion in the aldosterone-sensitive distal nephron of the kidney. Common causes for hyperkalaemia include kidney failure, limited delivery of sodium and water to the distal nephron and drugs that inhibit the renin-angiotensin-aldosterone system. Treatment of life-threatening hyperkalaemia (particularly those patients with ECG changes) involves administration of intravenous calcium salts to stabilise the resting cardiac membrane potential. The potassium concentration can be lowered by administration of intravenous insulin combined with an infusion of glucose to stimulate intracellular uptake of potassium. Nebulised β-2 adrenoceptor agonists can augment the effects of intravenous insulin and glucose pending more definitive management of the recurrent hyperkalaemia risk. Additional management steps include stopping further potassium intake and careful review of prescribed drugs that may be adversely affecting potassium homeostasis. Changes to prescribing systems and an agreed institutional protocol for management of hyperkalaemia can improve patient safety for this frequently encountered electrolyte disorder.

Circadian rhythm of blood and urinary copper in presumably healthy subjects of vegetarian food habit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhattacharya, R.D.

Circadian rhythm of blood and urinary copper has been studied in presumably healthy subjects of a particular ethnic group in India who are vegetarians. A definite 24-hr variation has been observed for both blood and urinary copper. The peak for blood copper was 1500 hr and the lowest value was 0600 hr, with values of 0.185 mg/100 ml and 0.160 mg/100 ml respectively. The urinary peak and trough occurred at 0600 and 0300 hr, respectively. Remarkably higher 24-hr copper excretion values were noted (64.49 ..mu..g/day) with a range of 15-100 ..mu..g/day. The blood level of copper (0.134 mg/100 ml) remainedmore » within the range reported. One subject out of 25 deviated from the group with respect to circadian phasing and amplitude to urinary copper excretion. 20 references.« less

Development and evaluation of adsorption sheet (HD safe sheet-U) using active carbon for the purpose of the preventing the contamination diffusion of urinary excreted anticancer drug.

PubMed

Sato, Junya; Ohkubo, Haruka; Sasaki, Yuki; Yokoi, Makoto; Hotta, Yasunori; Kudo, Kenzo

2017-01-01

Certain amount of anticancer drugs is excreted in the urine of patients receiving anticancer drugs, and urinary scattering including anticancer drugs at excretion has become a route of anticancer drug contamination. Therefore, we developed an active carbon sheet (HD safe sheet-U) that prevented diffusion by adsorbing anticancer drugs including that excreted in urine. The present study conducted a performance evaluation of this sheet. The adsorption performance of active carbon to anticancer drug in the urine was evaluated by determining concentration changes in the active carbon suspension (5 mg/mL) of 14 kinds of anticancer drugs (cyclophosphamide, ifosfamide, carboplatin, cisplatin, methotrexate, 5-fluorouracil, cytarabine, gemcitabine, doxorubicin, epirubicin, paclitaxel, docetaxel, etoposide, and irinotecan) diluted with artificial urine. Adhesion of the anticancer drug dropping on the sheet to a slipper sole was evaluated because urine including anticancer drugs is scattered on the floor, which can spread by adhering to shoe soles of patients and healthcare workers. The performance of the active carbon sheet was compared with two other types of medical adsorption sheets used as control sheets. Anticancer drugs diluted with artificial urine (1 mL) were dropped on the active carbon sheet and the two control sheets. The sheets were trod with slippers made by polyvinyl chloride. The adhered anticancer drug was wiped off and its quantity was determined. A remarkable decrease in anticancer drug concentrations, except for cisplatin, was detected by mixture of active carbon in the artificial urine (0-79.6%). The quantity of anticancer drug adhesion to slipper soles from the active carbon sheet was significantly lower compared with that observed for the two control sheets for eight kinds of anticancer drugs (cyclophosphamide, ifosfamide, carboplatin, methotrexate, cytarabine, gemcitabine, doxorubicin, and docetaxel). There was no adhesion in cyclophosphamide and docetaxel. Furthermore, the quantities of adhesion in cytarabine, gemcitabine, doxorubicin, paclitaxel, and irinotecan were lower than determination limit. Active carbon might be effective in adsorbing urinary anticancer drugs. The active carbon sheet adsorbed urinary excreted anticancer drugs, and use of such sheets might prevent diffusion of contamination due to urinary excreted anticancer drugs.

Ammonia Transporters and Their Role in Acid-Base Balance

PubMed Central

2017-01-01

Acid-base homeostasis is critical to maintenance of normal health. Renal ammonia excretion is the quantitatively predominant component of renal net acid excretion, both under basal conditions and in response to acid-base disturbances. Although titratable acid excretion also contributes to renal net acid excretion, the quantitative contribution of titratable acid excretion is less than that of ammonia under basal conditions and is only a minor component of the adaptive response to acid-base disturbances. In contrast to other urinary solutes, ammonia is produced in the kidney and then is selectively transported either into the urine or the renal vein. The proportion of ammonia that the kidney produces that is excreted in the urine varies dramatically in response to physiological stimuli, and only urinary ammonia excretion contributes to acid-base homeostasis. As a result, selective and regulated renal ammonia transport by renal epithelial cells is central to acid-base homeostasis. Both molecular forms of ammonia, NH3 and NH4+, are transported by specific proteins, and regulation of these transport processes determines the eventual fate of the ammonia produced. In this review, we discuss these issues, and then discuss in detail the specific proteins involved in renal epithelial cell ammonia transport. PMID:28151423

A case report of nephrogenic diabetes insipidus with idiopathic Fanconi syndrome in a child who presented with vitamin D resistant rickets.

PubMed

Patra, Soumya; Nadri, Gulnaz; Chowdhary, Harish; Pemde, Harish K; Singh, Varinder; Chandra, Jagdish

2014-05-01

Fanconi syndrome is a complex of multiple tubular dysfunctions of proximal tubular cells, occurring alone or in association with a variety of inherited (primary) or acquired (secondary) disorders. It is characterized by aminoaciduria, normoglycemic glycosuria, tubular proteinuria without hematuria, metabolic acidosis without anion gap and excessive urinary excretion of phosphorous, calcium, uric acid, bicarbonate, sodium, potassium and magnesium. Diabetes insipidus is a disease of collecting tubules and children mainly present with dehydration and hypernatremia. We are reporting the first case of idiopathic Fanconi's syndrome along with nephrogenic diabetes insipidus in a child who presented to us with vitamin D resistant rickets. Medline search did not reveal any case of nephrogenic diabetes insipidus (NDI) associated with idiopathic Fanconi syndrome. We hypothesized that the NDI may be due to to severe hypokalemia induced tubular dysfunction.

Nephrogenic diabetes insipidus with idiopathic Fanconi's syndrome in a child who presented as vitamin D resistant rickets.

PubMed

Patra, Soumya; Nadri, Gulnaz; Chowdhary, Harish; Pemde, Harish K; Singh, Varinder; Chandra, Jagdish

2011-10-01

Fanconi's syndrome is a complex of multiple tubular dysfunctions of proximal tubular cells occurring alone or in association with a variety of inherited (primary) or acquired (secondary) disorders. It is characterized by aminoaciduria, normoglycaemic glycosuria, tubular proteinuria without hematuria, metabolic acidosis without anion gap and excessive urinary excretion of phosphorous, calcium, uric acid, bicarbonate, sodium, potassium, and magnesium. Whereas diabetes insipidus is a disease of collecting tubules and child mainly presents with dehydration and hypernatremia. Though all the cases published till date were secondary to drugs, myeloma, hematological disorders, etc., we are reporting the first case of idiopathic Fanconi's syndrome along with nephrogenic diabetes insipidus in a child who presented to us as resistant rickets. Medline search did not reveal any case of nephrogenic diabetes insipidus associated with idiopathic Fanconi syndrome. We hypothesized that the NDI may be due to of severe hypokalemia induced tubular dysfunction.

Potential role of ammoniagenesis in the hypocalciuric effect of phosphorus in rats.

PubMed

Cerklewski, F L

1995-02-01

Hypocalciuria associated with a high phosphorus intake is known to be both a parathyroid hormone and non-parathyroid hormone dependent event. The present study was designed to define the role that ammoniagenesis may play in the non-parathyroid hormone dependent pathway. Male rats, initially weighing 160 g, were fed a purified diet containing, in g/kg diet, a single level of protein (200) and variable inorganic phosphorus (1.8, 4.5, 9.0) for 20 days. Food intake and body weight were similar for the three groups. Significant inverse correlations were found for both urinary calcium and phosphorus and for urinary ammonia nitrogen and calcium excretion (r = -0.62, p < 0.01). Urinary ammonia nitrogen excretion was highly correlated with both phosphorus intake (r = 0.89, p < 0.001) and urinary phosphorus (r = 0.88, p < 0.001). Urinary urea nitrogen tended to vary inversely with phosphorus intake. High dietary phosphorus decreased the activity of glutamine synthetase and increased the activity of glutaminase I in kidney. Tying-up some of the hydrogen ions destined for excretion by phosphorus-stimulated ammoniagenesis could reduce the interfering effect of hydrogen ion on kidney calcium reabsorption and provide a mechanism to explain why phosphorus can have a direct positive impact upon tubular calcium reabsorption.

Interesting Layering of Excreted 18F-FDG in the Urinary Bladder in Patients with Urinary Tract Infection and Distended Bladder.

PubMed

Shen, Guohua; Zhang, Wenjie; Jia, Zhiyun; Deng, Houfu

2015-09-01

Settling of (18)F-FDG in the bladder is often noted on whole-body PET/CT images, but this phenomenon has never received any careful attention and the mechanism has been unclear. The 2 patients described in this report, one with a T1 pathologic fracture and another with widespread bone and lymph node metastases from an unknown primary tumor, underwent PET/CT. Both had urinary tract infection and a distended bladder during scanning. The interesting layering of (18)F-FDG in the urinary bladder was observed in both patients. The presence of this phenomenon demands careful evaluation of the urine by the clinician, and the mechanism is hypothesized to be slow (18)F-FDG excretion in patients with a distended urinary bladder, resulting in delayed mixing with urine. In addition, urinary tract infection may be a potential cause. Images showing this interesting layering should be interpreted with care. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Effect of Hygrophila spinosa in ethylene glycol induced nephrolithiasis in rats.

PubMed

Ingale, Kundan G; Thakurdesai, Prasad A; Vyawahare, Neeraj S

2012-01-01

Hygrophila spinosa (Acanthaceae) is traditionally used to treat urinary calculi. The present study aimed to evaluate the antiurolithiatic activity of methanolic extract of Hygrophila spinosa (Acanthaceae) in ethylene glycol induced nephrolithiasic rats. Methanolic extract of Hygrophila spinosa (HSME) (250 and 500 mg/ kg body weight) was administered orally to male Wistar albino rats. Ethylene glycol (EG) was used to induce nephrolithiasis. The parameters studied included water intake, urinary volume, urinary pH, urinary and kidney oxalate and calcium, urinary magnesium and serum uric acid. Ethylene glycol feeding resulted in hyperoxaluria as well as increased renal excretion of calcium and serum uric acid along with decreased excretion of urinary magnesium. Treatment with HSME significantly reduced the elevated urinary oxalate, urinary calcium and serum uric acid with increase in reduced urinary magnesium. Ethylene glycol feeding also resulted in increased levels of calcium and oxalate in kidney which was decreased after the treatment with HSME. The increased deposition of stone forming constituents in the kidneys of ethylene glycol treated rats was significantly lowered by treatment with HSME. The results indicate that the aerial parts of Hygrophila spinosa are endowed with antiurolithiatic activity, thereby justifying its traditional claim.

Urinary metabolites of histamine and leukotrienes before and after placebo-controlled challenge with ASA and food additives in chronic urticaria patients.

PubMed

Di Lorenzo, G; Pacor, M L; Vignola, A M; Profita, M; Esposito-Pellitteri, M; Biasi, D; Corrocher, R; Caruso, C

2002-12-01

The recovery of mediator metabolites from urine has the potential to provide a rapid, safe, and easily available index of release of mediators. We aimed to determine urinary metabolites of both histamine and leukotrienes (LTs) in patients affected by chronic urticaria (CU). Twenty patients with CU were studied. They were selected on the basis of double-blind placebo-controlled challenge (DBPC) with acetyl salicylic acid (ASA) and food additives. Ten patients (group B) were negative to both challenges. Ten patients (group C) presented urticaria and/or the appearance of angioedema during or 24 h after challenge, with reactions to ASA (five patients) or food additives (five patients). We recruited 15 healthy volunteers as controls (group A). During a second challenge, groups B and C were challenged double-blind with a single dose of ASA, or a specific food additive, or placebo. The healthy group was challenged only with a placebo (talc capsule). Patients in groups B and C were challenged twice: with placebo (as groups B1 and C1) and with ASA (groups B2 and C2) or food additives (C2). Four samples of urine were collected; one during the night before the specific or sham challenge (baseline), and three at 2, 6 and 24 h after the challenge. Urinary methylhistamine (N-MH) and LTE4 were analyzed and normalized for urinary creatinine. For urinary N-MH at baseline, there was a significant difference only between group A and groups B1, B2, C1 and C2 (A vs. B1, P < 0.0001; A vs. B2, P < 0.0001; A vs. C1, P < 0.0001; A vs. C2, P < 0.0001). We detected a significant variation in urinary methylhistamine excretion only in group C2 after 2 h, 6 h and 24 h (P < 0.0001). However, no variations were observed in N-MH excretion rate in the other groups (A, B1, C1) after challenge with placebo, and in B2 after challenge with ASA 20 mg. For urinary LTE4 at baseline no differences were found between the mean values for the different groups. After specific challenge, only C2 patients showed significantly increased excretion rates of urinary LTE4 compared with the other groups challenged with placebo (A, B1, C1), or ASA (B2) (P < 0.0001). No significant correlation was seen between urinary LTE4 and methylhistamine excretion rate in any patients. Our results show that urinary excretion of N-MH and LTE4 is different for CU patients without ASA or food hypersensitivity, compared to those with CU with ASA or food additive hypersensitivity after specific challenge.

Estimation model for habitual 24-hour urinary-sodium excretion using simple questionnaires from normotensive Koreans.

PubMed

Kong, Ji-Sook; Lee, Yeon-Kyung; Kim, Mi Kyung; Choi, Mi-Kyeong; Heo, Young-Ran; Hyun, Taisun; Kim, Sun Mee; Lyu, Eun-Soon; Oh, Se-Young; Park, Hae-Ryun; Rhee, Moo-Yong; Ro, Hee-Kyong; Song, Mi Kyung

2018-01-01

This study was conducted to develop an equation for estimation of 24-h urinary-sodium excretion that can serve as an alternative to 24-h dietary recall and 24-h urine collection for normotensive Korean adults. In total, data on 640 healthy Korean adults aged 19 to 69 years from 4 regions of the country were collected as a training set. In order to externally validate the equation developed from that training set, 200 subjects were recruited independently as a validation set. Due to heterogeneity by gender, we constructed a gender-specific equation for estimation of 24-h urinary-sodium excretion by using a multivariable linear regression model and assessed the performance of the developed equation in validation set. The best model consisted of age, body weight, dietary behavior ('eating salty food', 'Kimchi consumption', 'Korean soup or stew consumption', 'soy sauce or red pepper paste consumption'), and smoking status in men, and age, body weight, dietary behavior ('salt preference', 'eating salty food', 'checking sodium content for processed foods', 'nut consumption'), and smoking status in women, respectively. When this model was tested in the external validation set, the mean bias between the measured and estimated 24-h urinary-sodium excretion from Bland-Altman plots was -1.92 (95% CI: -113, 110) mmol/d for men and -1.51 (95% CI: -90.6, 87.6) mmol/d for women. The cut-points of sodium intake calculated based on the equations were ≥4,000 mg/d for men and ≥3,500 mg/d for women, with 89.8 and 76.6% sensitivity and 29.3 and 64.2% specificity, respectively. In this study, a habitual 24-hour urinary-sodium-excretion-estimation model of normotensive Korean adults based on anthropometric and lifestyle factors was developed and showed feasibility for an asymptomatic population.

Estimation model for habitual 24-hour urinary-sodium excretion using simple questionnaires from normotensive Koreans

PubMed Central

Choi, Mi-Kyeong; Heo, Young-Ran; Hyun, Taisun; Kim, Sun Mee; Lyu, Eun-Soon; Oh, Se-Young; Park, Hae-Ryun; Rhee, Moo-Yong; Ro, Hee-Kyong; Song, Mi Kyung

2018-01-01

This study was conducted to develop an equation for estimation of 24-h urinary-sodium excretion that can serve as an alternative to 24-h dietary recall and 24-h urine collection for normotensive Korean adults. In total, data on 640 healthy Korean adults aged 19 to 69 years from 4 regions of the country were collected as a training set. In order to externally validate the equation developed from that training set, 200 subjects were recruited independently as a validation set. Due to heterogeneity by gender, we constructed a gender-specific equation for estimation of 24-h urinary-sodium excretion by using a multivariable linear regression model and assessed the performance of the developed equation in validation set. The best model consisted of age, body weight, dietary behavior (‘eating salty food’, ‘Kimchi consumption’, ‘Korean soup or stew consumption’, ‘soy sauce or red pepper paste consumption’), and smoking status in men, and age, body weight, dietary behavior (‘salt preference’, ‘eating salty food’, ‘checking sodium content for processed foods’, ‘nut consumption’), and smoking status in women, respectively. When this model was tested in the external validation set, the mean bias between the measured and estimated 24-h urinary-sodium excretion from Bland-Altman plots was -1.92 (95% CI: -113, 110) mmol/d for men and -1.51 (95% CI: -90.6, 87.6) mmol/d for women. The cut-points of sodium intake calculated based on the equations were ≥4,000 mg/d for men and ≥3,500 mg/d for women, with 89.8 and 76.6% sensitivity and 29.3 and 64.2% specificity, respectively. In this study, a habitual 24-hour urinary-sodium-excretion-estimation model of normotensive Korean adults based on anthropometric and lifestyle factors was developed and showed feasibility for an asymptomatic population. PMID:29447201

Tissue accumulation and urinary excretion of chromium in rats fed diets containing graded levels of chromium chloride or chromium picolinate.

PubMed

Yoshida, Munehiro; Hatakeyama, Erika; Hosomi, Ryota; Kanda, Seiji; Nishiyama, Toshimasa; Fukunaga, Kenji

2010-08-01

To attempt a risk assessment of the excess intake of trivalent chromium (Cr), tissue Cr accumulation and urinary Cr excretion were examined in weanling rats fed experimental diets containing graded levels of Cr chloride (CrCl3) or Cr picolinate (CrPic). Thirty-six male weanling 4-weeks-old Wistar rats were divided into six groups and fed a casein-based semi-purified diet (Cr content: <0.02 microg/g) supplemented with 1, 10, or 100 microg Cr/g as CrCl3 or CrPic for 28 days. Among the experimental groups, no significant difference was observed in body weight; however, supplementation of 100 microg Cr/g to the diets caused a significant low liver weight irrespective of the chemical species of Cr. Activities of serum aspartate aminotransferase and alanine aminotransferase were significantly elevated in rats given CrPic at 100 microg Cr/g. In the liver, kidney and femur, Cr accumulation increased with elevation of the dietary Cr level. No influence of the difference in the chemical species of supplemented Cr was observed in the liver and kidney, but CrCl3 caused significantly higher Cr accumulation than CrPic in the femur of rats given 100 microg Cr/g. Daily urinary Cr excretion elevated with the increase of the dietary Cr level. Rats given CrPic showed significantly higher daily urinary Cr excretion than those given CrCl3, particularly at a dietary Cr level of 100 microg/g. The rate of urinary Cr excretion in rats given CrPic was constant, irrespective of the dietary Cr level, but that of rats given CrCl3 fell with the increase of the dietary Cr level. These results indicate that the lowest adverse effect level of dietary Cr is less than 100 microg/g, irrespective of the chemical species of Cr.

[Field observation on the effect of low-sodium and high-potassium salt substitute on blood pressure in the rural community-based population in China].

PubMed

Zhang, Gao-hui; Ma, Ji-xiang; Guo, Xiao-lei; Dong, Jing; Chen, Xi; Zhang, Ji-yu; Su, Jun-ying; Tang, Jun-li; Xu, Ai-qiang

2011-09-01

To investigate the effect of commercial low-sodium and high-potassium salt substitutes on blood pressure in the rural community-based population in China. We conducted a quasi-experiment on 411 adults, who were 30 to 60 years of age, in 2 rural communities from Laiwu city in Shandong province of China on data from blood pressure screening. The subjects were divided into 2 groups: high blood pressure (HBP) and non-HBP (NHBP). Both groups and their family members took a low-sodium and high-potassium salt substitute for 3 months to replace the normal salt in their bodies. Blood pressure (BP) and 24-hour urinary sodium and potassium were measured regularly in the 2 groups. There was a continuously decreasing trend for BP at the end of the first month. Three months later, the mean BP decreased by 7.4 mm Hg (1 mm Hg = 0.133 kPa, t = 10.096, P = 0.000) for SBP and 3.8 mm Hg (t = 8.017, P = 0.000) for DBP in the HBP group, when compared to a 1.2 mm Hg (t = 2.507, P = 0.007) decrease on SBP and 1.0 mm Hg (t = 2.987, P = 0.002) on DBP in the NHBP group. The mean urinary sodium had a decrease of 15.5 mmol/24 h (t = 1.803, P = 0.037), but the urinary potassium increased by 4.2 mmol/24 h (t' = 2.132, P = 0.018). The result of urinary sodium appeared to be as follows: potassium ratio (Na(+)/K(+)) decreased by 1.2 (t = 2.786, P = 0.003) in the HBP group. However, in NHBP group, the mean urinary sodium decreased by 1.7 mmol/24 h (t = 0.211, P = 0.417) and urinary potassium increased by 3.7 mmol/24 h (t' = 2.207, P = 0.015), together with the decrease of Na(+)/K(+) by 0.7 (t = 1.818, P = 0.036). Results from our study clearly demonstrated that the intake of low-sodium and high-potassium salt substitute could effectively reduce the BP with good compliance among adults in the rural community-based population in China. This was an effective but non-medical method to prevent and control the high blood pressure.

[A study on the effects of a Mg-deficient diet on blood pressure and various hormonal systems in Wistar rats and spontaneously hypertensive rats].

PubMed

Honda, M; Izumi, Y; Hatano, M

1988-08-20

The influence of a Mg-deficient diet on blood pressure and various hormonal systems was examined in Wistar rats (WR) and spontaneously hypertensive rats (SHR). The WR and SHR were individually divided into 2 groups. The Mg-deficient diet was given to one group, and a Mg-containing diet was given to the other group for 3 weeks. During this experimental period, the body weight, blood pressure, urine volume, blood and urinary electrolytes, plasma steroid hormones, plasma renin activity (PRA), and urinary hormones [kinin, prostaglandin E2 (PGE2), 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), and noradrenaline] were examined. Although no significant difference in body weight was observed between the Mg-deficient and Mg-containing diet groups in either the WR or SHR (because the experiments were performed in a pair-fed fashion in both kinds of rat), the blood pressure was increased in the Mg-containing diet group but was unchanged in the Mg-deficient diet group. As regards changes in electrolytes, a decreased urinary excretion of Mg and significantly increased urinary excretion of P were observed in the Mg-deficient diet group in both the WR and SHR. Furthermore, decreased levels of serum Mg and P and increased levels of serum Ca were also noted. In the WR group, the urinary excretion of noradrenaline was significantly increased in the Mg-deficient diet group as compared to the Mg-containing diet group. However, the change was reversed in the SHR group. The plasma steroid hormones and PRA were both significantly low in the Mg-deficient diet group in both the WR and SHR. The urinary excretions of PGE2, 6-keto-PGF1 alpha, and kinin showed no significant differences between the two diet groups. The above results indicate that blood pressure is not affected by the Mg-deficient diet in either the WR or SHR, and the possible participation of the sympathetic nervous system in the mechanism of control of blood pressure may differ somewhat between the WR and SHR. In addition, Mg ion was found to play an important role in the biosynthesis of renin and steroid hormones but to have no such significant role in the urinary excretions of kinin, PGE2, and 6-keto-PGF1 alpha.

5C.07: A METHOD TO ESTIMATE 24-HOUR SODIUM EXCRETION THROUGH SPOT URINE SAMPLES AND ITS APPLICATION VALUE FOR TARGET-ORGAN DAMAGE ASSESSMENT.

PubMed

Wang, H; Zhao, L; Xi, Y; Sun, N

2015-06-01

24-h urine sodium excretion is considered the most reliable method to evaluate the salt intakes. However, this method is cumbersome. So we want to develop formulas to estimate 24-h urinary sodium excretion using spot urinary samples in Chinese hypertensive population and explore the application value of this method in salt intake assessment and target organ damage. 1. We enrolled 510 cases of hospitalized patients with hypertension, 2/3 of them were arranged randomly to formula group to develop a new formula and the remainings were used to test the performance of the formula. All participants were instructed to collect a 24-h urine sample, a second morning voiding urine sample (SMU), and a post-meridiem urine sample in the late afternoon or early evening, prior to the evening meal (PMU). All samples were sent to measure sodium and creatinine concentration.2. We compared the differences of office blood pressure, 24-hour ambulatory blood pressure and left ventricular hypertrophy, vascular stiffness and urine protein among groups of different sodium intake. 24hour sodium excretion formulas was obtained using SMU and PMU respectively, which have good cosistency. The difference between the estimated and measured values in sodium excretion is 12.66mmol/day (SMU) and 9.41mmol/day (PM), to be equal to 0.7 g (SMU) and 0.6 g (PM) salt intake. Comparing with Kawasaki and Tanaka method, the new formula shows the lower degree of deviation, and higher accuracy and precision. Blood pressure of high urinary sodium group is higher than that in low urinary sodium group (P < 0.05). Left ventricular hypertrophy and urinary albumin/creatinine aggravated with the salt intake increase, this has eliminated the influence of other factors. All of morphologies of the relationship between ambulatory arterial stiffness index, pulse wave velocity and carotid intima-media thickness with quartiles of sodium intake resembled a J-shaped curve. In Chinese hypertensive population, the formulas to estimate 24-h urinary sodium using spot urinary samples spot urine are considered useful for estimating the mean level of population salt intake, and have a role in evaluating target organ damage.

Collagen cross-link excretion during space flight and bed rest

NASA Technical Reports Server (NTRS)

Smith, S. M.; Nillen, J. L.; Leblanc, A.; Lipton, A.; Demers, L. M.; Lane, H. W.; Leach, C. S.; LeBlanc, A. (Principal Investigator)

1998-01-01

Extended exposure to weightlessness results in bone loss. However, little information exists as to the precise nature or time course of this bone loss. Bone resorption results in the release of collagen breakdown products, including N-telopeptide and the pyridinium (PYD) cross-links, pyridinoline and deoxypyridinoline. Urinary pyridinoline and deoxypyridinoline are known to increase during bed rest. We assessed excretion of PYD cross-links and N-telopeptide before, during, and after long (28-day, 59-day, and 84-day) Skylab missions, as well as during short (14-day) and long (119-day) bed-rest studies. During space flight, the urinary cross-link excretion level was twice those observed before flight. Urinary excretion levels of the collagen breakdown products were also 40-50% higher, during short and long bed rest, than before. These results clearly show that the changes in bone metabolism associated with space flight involve increased resorption. The rate of response (i.e. within days to weeks) suggests that alterations in bone metabolism are an early effect of weightlessness. These studies are important for a better understanding of bone metabolism in space crews and in those who are bedridden.

Technical note: Evaluation of urinary purine derivatives in comparison with duodenal purines for estimating rumen microbial protein supply in sheep.

PubMed

Kozloski, G V; Stefanello, C M; Oliveira, L; Filho, H M N Ribeiro; Klopfenstein, T J

2017-02-01

A data set of individual observations was compiled from digestibility trials to examine the relationship between the duodenal purine bases (PB) flow and urinary purine derivatives (PD) excretion and the validity of different equations for estimating rumen microbial N (Nm) supply based on urinary PD in comparison with estimates based on duodenal PB. Trials (8 trials, = 185) were conducted with male sheep fitted with a duodenal T-type cannula, housed in metabolic cages, and fed forage alone or with supplements. The amount of PD excreted in urine was linearly related to the amount of PB flowing to the duodenum ( < 0.05). The intercept of the linear regression was 0.180 mmol/(d·kg), representing the endogenous excretion of PD, and the slope was lower than 1 ( < 0.05), indicating that only 0.43% of the PB in the duodenum was excreted as PD in urine. The Nm supply estimated by either approach was linearly related ( < 0.05) to the digestible OM intake. However, the Nm supply estimated through either of 3 published PD-based equations probably underestimated the Nm supply in sheep.

Urinary excretion of water-soluble vitamins increases in streptozotocin-induced diabetic rats without decreases in liver or blood vitamin content.

PubMed

Imai, Eri; Sano, Mitsue; Fukuwatari, Tsutomu; Shibata, Katsumi

2012-01-01

It is thought that the contents of water-soluble vitamins in the body are generally low in diabetic patients because large amounts of vitamins are excreted into urine. However, this hypothesis has not been confirmed. To investigate this hypothesis, diabetes was induced in male Wistar rats (6 wk old) by streptozotocin treatment, and they were then given diets containing low, medium or sufficient vitamins for 70 d. The contents of 6 kinds of B-group vitamins, namely vitamin B₁, vitamin B₂, vitamin B₆, vitamin B₁₂, folate and biotin, were determined in the urine, blood and liver. No basic differences among the dietary vitamin contents were observed. The urinary excretion of vitamins was higher in diabetic rats than in control rats. The blood concentrations of vitamin B₁₂ and folate were lowered by diabetes, while, those of vitamin B₁, vitamin B₂, vitamin B₆, and biotin were not. All liver concentrations of vitamins were increased in diabetic rats above those in control rats. These results showed that streptozotocin-induced diabetes increased urinary excretion of water-soluble vitamins, though their blood and liver concentrations were essentially maintained in the rats.

Sodium and potassium intake and risk of cardiovascular events and all-cause mortality: the Rotterdam Study

PubMed Central

Witteman, Jacqueline C. M.; Stijnen, Theo; Kloos, Margot W.; Hofman, Albert; Grobbee, Diederick E.

2007-01-01

Background Dietary electrolytes influence blood pressure, but their effect on clinical outcomes remains to be established. We examined sodium and potassium intake in relation to cardiovascular disease (CVD) and mortality in an unselected older population. Methods A case–cohort analysis was performed in the Rotterdam Study among subjects aged 55 years and over, who were followed for 5 years. Baseline urinary samples were analyzed for sodium and potassium in 795 subjects who died, 206 with an incident myocardial infarction and 181 subjects with an incident stroke, and in 1,448 randomly selected subjects. For potassium, dietary data were additionally obtained by food-frequency questionnaire for 78% of the cohort. Results There was no consistent association of urinary sodium, potassium, or sodium/potassium ratio with CVD and all-cause mortality over the range of intakes observed in this population. Dietary potassium estimated by food frequency questionnaire, however, was associated with a lower risk of all-cause mortality in subjects initially free of CVD and hypertension (RR = 0.71 per standard deviation increase; 95% confidence interval: 0.51–1.00). We observed a significant positive association between urinary sodium/potassium ratio and all-cause mortality, but only in overweight subjects who were initially free of CVD and hypertension (RR = 1.19 (1.02–1.39) per unit). Conclusion The effect of sodium and potassium intake on CVD morbidity and mortality in Western societies remains to be established. PMID:17902026

Eclampsia despite strict dietary sodium restriction.

PubMed

Delemarre, F M; Steegers, E A; Berendes, J N; de Jong PA

2001-01-01

The classic indication for prescribing dietary sodium restriction in pregnancy has been the prevention of eclampsia. We describe a case of intrapartum eclampsia in a 24-year-old nulliparous woman. A strongly sodium restricted diet was prescribed because of pre-eclampsia. Compliance to the diet was checked with 24-hour urinary sodium excretion. This report, describing the first case of eclampsia despite neglectable urinary sodium excretion, adds to the view that sodium restriction in pregnancy is obsolete. Copyright 2001 S. Karger AG, Basel.

Alteration of renal excretion pathways in gentamicin-induced renal injury in rats.

PubMed

Ma, Yan-Rong; Luo, Xuan; Wu, Yan-Fang; Zhang, Tiffany; Zhang, Fan; Zhang, Guo-Qiang; Wu, Xin-An

2018-07-01

The kidney plays a major part in the elimination of many drugs and their metabolites, and drug-induced kidney injury commonly alters either glomerular filtration or tubular transport, or both. However, the renal excretion pathway of drugs has not been fully elucidated at different stages of renal injury. This study aimed to evaluate the alteration of renal excretion pathways in gentamicin (GEN)-induced renal injury in rats. Results showed that serum cystatin C, creatinine and urea nitrogen levels were greatly increased by the exposure of GEN (100 mg kg -1 ), and creatinine concentration was increased by 39.7% by GEN (50 mg kg -1 ). GEN dose-dependently upregulated the protein expression of rOCT1, downregulated rOCT2 and rOAT1, but not affected rOAT2. Efflux transporters, rMRP2, rMRP4 and rBCRP expressions were significantly increased by GEN(100), and the rMATE1 level was markedly increased by GEN(50) but decreased by GEN(100). GEN(50) did not alter the urinary excretion of inulin, but increased metformin and furosemide excretion. However, GEN(100) resulted in a significant decrease of the urinary excretion of inulin, metformin and p-aminohippurate. In addition, urinary metformin excretions in vivo were significantly decreased by GEN(100), but slightly increased by GEN(50). These results suggested that GEN(50) resulted in the induction of rOCTs-rMATE1 and rOAT3-rMRPs pathway, but not changed the glomerular filtration rate, and GEN(100)-induced acute kidney injury caused the downregulated function of glomerular filtration -rOCTs-rMATE1 and -rOAT1-rMRPs pathway. Copyright © 2018 John Wiley & Sons, Ltd.

LY3127760, a Selective Prostaglandin E4 (EP4) Receptor Antagonist, and Celecoxib: A Comparison of Pharmacological Profiles.

PubMed

Jin, Yan; Smith, Claire; Hu, Leijun; Coutant, David E; Whitehurst, Kelly; Phipps, Krista; McNearney, Terry Ann; Yang, Xiao; Ackermann, Bradley; Pottanat, Thomas; Landschulz, William

2018-01-01

Safety, tolerability, and pharmacology profiles of LY3127760, an EP4 antagonist, were explored in healthy subjects in a subject/investigator-blind, parallel-group, multiple-ascending dose study. Cohorts consisted of 13 patients randomized to LY3127760, celecoxib (400 mg), or placebo (9:2:2 ratio) for 28 days. LY3127760 was well tolerated; the most commonly observed adverse events were gastrointestinal, similar to celecoxib. LY3127760 increased release of ex vivo tumor necrosis factor alpha after lipopolysaccharide/prostaglandin E2 stimulation when compared with placebo, suggesting a dose-dependent blockade of the EP4 receptor. Compared with placebo, 24-h urinary excretion of prostaglandin E metabolite was modestly increased; prostacyclin metabolite was inhibited; and thromboxane A2 metabolite was unchanged. Effects on sodium and potassium excretion were similar to those of celecoxib. We conclude that LY3127760 demonstrated similar effects on prostacyclin synthesis and renal sodium retention as celecoxib. These data support exploration of LY3127760 at daily doses of 60 mg to 600 mg in phase II trials. This trial's registration number: NCT01968070. © 2017 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Pre-stimulation of the kallikrein system in cisplatin-induced acute renal injury: An approach to renoprotection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aburto, Andrés; Barría, Agustín; Cárdenas, Areli

Antineoplastic treatment with cisplatin is frequently complicated by nephrotoxicity. Although oxidative stress may be involved, the pathogenic mechanisms responsible for renal damage have not been completely clarified. In order to investigate the role of the renal kinin system in this condition, a group of rats was submitted to high potassium diet to stimulate the synthesis and excretion of tissue kallikrein 1 (rKLK1) previous to an intraperitoneal injection of 7 mg/kg cisplatin. A significant reduction in lipoperoxidation, evidenced by urinary excretion of malondialdehyde and renal immunostaining of hidroxy-nonenal, was accompanied by a decline in apoptosis. Coincident with these findings we observedmore » a reduction in the expression of renal KIM-1 suggesting that renoprotection may be occurring. Stimulation or indemnity of the renal kinin system deserves to be evaluated as a complementary pharmacological measure to diminish cisplatin nephrotoxicity. - Highlights: • Mechanisms of cisplatin-induced-renal damage have not been completely clarified. • Cisplatin induces oxidative stress and apoptosis. • The renal kallikrein-kinin system is protective in experimental acute renal damage. • Kallikrein stimulation reduces oxidative stress and apoptosis induced by cisplatin. • Protection of the kallikrein-kinin system may reduce cisplatin toxicity.« less

Urinary Excretion of Niacin Metabolites in Humans After Coffee Consumption.

PubMed

Kremer, Jonathan Isaak; Gömpel, Katharina; Bakuradze, Tamara; Eisenbrand, Gerhard; Richling, Elke

2018-04-01

Coffee is a major natural source of niacin in the human diet, as it is formed during coffee roasting from the alkaloid trigonelline. The intention of our study was to monitor the urinary excretion of niacin metabolites after coffee consumption under controlled diet. We performed a 4-day human intervention study on the excretion of major niacin metabolites in the urine of volunteers after ingestion of 500 mL regular coffee containing 34.8 μmol nicotinic acid (NA) and 0.58 μmol nicotinamide (NAM). In addition to NA and NAM, the metabolites N 1 -methylnicotinamide (NMNAM), N 1 -methyl-2-pyridone-5-carboxamide (2-Py), and nicotinuric acid (NUA) were identified and quantified in the collected urine samples by stable isotope dilution analysis (SIVA) using HPLC-ESI-MS/MS. Rapid urinary excretion was observed for the main metabolites (NA, NAM, NMNAM, and 2-Py), with t max values within the first hour after ingestion. NUA appeared in traces even more rapidly. In sum, 972 nmol h -1 of NA, NAM, NMNAM, and 2-Py were excreted within 12 h after coffee consumption, corresponding to 6% of the ingested NA and NAM. The results indicate regular coffee consumption to be a source of niacin in human diet. © 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantification of acetylcholine, choline, betaine, and dimethylglycine in human plasma and urine using stable-isotope dilution ultra performance liquid chromatography-tandem mass spectrometry.

PubMed

Kirsch, Susanne H; Herrmann, Wolfgang; Rabagny, Yannick; Obeid, Rima

2010-12-15

Disorders in choline metabolism are related to disease conditions. We developed a stable-isotope dilution ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS) method for the simultaneous quantification of acetylcholine (ACh), betaine, choline, and dimethylglycine (DMG). We used this method to measure concentrations of the analytes in plasma and urine in addition to other biological fluids after a protein precipitation by acetonitrile. The detection limits were between 0.35 nmol/L (for ACh in urine) and 0.34 μmol/L (for betaine in urine). ACh concentrations were not detectable in plasma. Intraassay and interassay coefficient of variation (CVs) were all <10.0% in biological fluids, except for DMG in cerebrospinal fluid (CV=12.44%). Mean recoveries in urine pool samples were between 99.2% and 103.9%. The urinary excretion of betaine, choline, and DMG was low, with approximately 50.0% higher excretion of choline in females compared to males. Median urinary excretion of ACh were 3.44 and 3.92 μmol/mol creatinine in males and females, respectively (p=0.689). Plasma betaine concentrations correlated significantly with urinary excretions of betaine (r=0.495, p=0.027) and choline (r=0.502, p=0.024) in females. Plasma choline concentrations correlated significantly with urinary excretion of ACh in males (r=0.419, p=0.041) and females (r=0.621, p=0.003). The new method for the simultaneous determination of ACh, betaine, choline, and DMG is sensitive, precise, and fast enough to be used in clinical investigations related to the methylation pathway. Copyright © 2010 Elsevier B.V. All rights reserved.

L-carnitine and cancer cachexia. I. L-carnitine distribution and metabolic disorders in cancer cachexia.

PubMed

Szefel, Jarosław; Kruszewski, Wiesław Janusz; Ciesielski, Maciej; Szajewski, Mariusz; Kawecki, Krzysztof; Aleksandrowicz-Wrona, Ewa; Jankun, Jerzy; Lysiak-Szydłowska, Wiesława

2012-07-01

Cancer cachexia (CC), a progressive loss of body mass, is associated with decreased energy production. Abnormally low levels of L-carnitine (LC) in skeletal muscle means that mitochondrial β-oxidation of long-chain fatty acids (LCFA) does not occur efficiently in patients with CC. We assessed the influence of CC on LC distribution and the effects of parenteral lipid emulsions on plasma LC levels and urinary excretion. Fifty patients with CC were randomly assigned to total parenteral nutrition (TPN) with long-chain triglycerides (LCTs), or LCTs plus medium-chain triglycerides (MCTs) as 50/50. Patients were further separated into those with body-mass index (BMI) ≤ 19 kg/m(2) and BMI >19 kg/m(2). Plasma concentrations of total LC (TC) and free LC (FC) and their urinary excretion were measured, along with skeletal muscle LC levels. On average, plasma FC and TC were higher than reference values in all patients. Patients with BMI ≤ 19 kg/m(2) had lower plasma FC and TC than those with BMI >19 kg/m(2). Skeletal muscle FC in the BMI ≤ 19 kg/m(2) group was lower than reference value, but within the normal range in others. LC and FC urinary excretion was higher than reference values. Plasma LC and its urinary excretion were higher in patients administered pure LCTs relative to those given MCTs/LCTs. A decrease in skeletal muscle LC in cancer patients with CC (BMI ≤ 19 kg/m(2)) correlates with an increase in its plasma levels and increased renal excretion. A diet of MCTs/LCTs reduces LC release from muscle to plasma and urine more effectively than LCTs.

Effects of dietary benzoic acid and sodium-benzoate on performance, nitrogen and mineral balance and hippuric acid excretion of piglets.

PubMed

Gräber, Tobias; Kluge, Holger; Hirche, Frank; Broz, Jirí; Stangl, Gabriele I

2012-06-01

The objective of this study was to compare the effects of sodium-benzoate (NaB) with those of benzoic acid (BAc) on growth performance of piglets as well as nutrient digestibility, nitrogen and mineral balance, urinary pH, and the urinary excretion of BAc and hippuric acid (HAc). The study was conducted with 120 weaning piglets (6.5 kg body weight), divided in four groups (15 replicates of two piglets each), which received (1) a basal diet (Control), or the basal diet supplemented with (2) 4 g NaB per kg (Group 4NaB), (3) 3.5 g BAc per kg (Group 3.5BAc) or (4) 5 g BAc per kg (Group 5BAc). Performance data were monitored over a 42-day period. Urine and faeces were collected from day 28-33 in metabolic cages with five piglets per treatment. Piglets of Groups 3.5BAc and 5BAc had similarly a considerably improved average daily gain and feed intake (p < 0.05). Performance of Group 4NaB was not significantly different from the other groups. Compared to the Control, the nitrogen retention was only improved in Group 5BAc (p < 0.05); the other groups showed intermediate values. In the supplemented groups, most of the BAc was excreted as HAc in urine, but only Groups 3.5BAc and 5BAc had reduced urinary pH (p < 0.05). Daily intake and faecal and urinary excretion of P and Ca were not affected by the treatment. The molar excess of Na in Group 4NaB was reflected by higher renal excretion of Na compared to the other groups (p < 0.05).

[Influence of mineral water on absorption of oral alendronate in rats].

PubMed

Akagi, Yuuki; Sakaue, Tomoyuki; Yoneyama, Eiji; Aoyama, Takao

2011-01-01

Alendronate, an oral bisphosphonate (e.g., Fosamax(®)), is effective in the treatment of osteoporosis, and the Fosamax(®) package insert advises that the bioavailability is reduced when taken with mineral water containing high levels of metal cations (Ca(2+), Mg(2+), etc.). However, standards regarding the water used when taking alendronate are unclear. In this study, the influence of mineral water on the absorption of oral alendronate was investigated based on urinary excretion of its unchanged form in rats. Alendronate was diluted in each water sample and administered orally (0.7 mg/kg) to male Wistar rats after 24-hour fast. Urine samples were collected until 24 h after dosing. Urine samples were alkalinized, and alendronate in urine was precipitated as a calcium salt, followed by loading on an anion exchange cartridge. Eluted alendronate was derivatized with 9-fluorenylmethoxycarbonyl (Fmoc) chloride and determined by HPLC with fluorescent detection. Cumulative urinary excretion recoveries of alendronate were calculated from the amounts of urinary excretion. Alendronate was rapidly excreted in the first 6 h, and similar elimination rate constants were seen (from 0.28 to 0.45 h(-1/2)) among the water samples. Cumulative urinary excretion recoveries with tap water, evian(®) and 100% deep ocean water were 0.98±0.17%, 0.80±0.18% and 1.01±0.16% (mean±S.E., n=4). Those with Contrex(®) (0.33±0.07%) were significantly lower when compared with ultrapure water (1.56±0.35%, p<0.01). These findings suggest that the absorption of alendronate decreases based on the calcium concentration of mineral water. In conclusion, mineral water containing high levels of calcium is not recommended when alendronate is taken.

Urinary 2,5-hexanedione excretion in cryptogenic polyneuropathy compared to the general Swedish population

PubMed Central

2013-01-01

Background 2,5-hexanedione (2,5-HD) is the main neurotoxic metabolite of methyl-n-butyl ketone (MBK) and n-hexane, and known to cause polyneuropathy. The aim of our study was to compare the urinary levels of 2,5-HD between cases with cryptogenic polyneuropathy and the general Swedish population, and to elucidate the role of certain external factors. Methods Morning urine samples were collected from 114 cases with cryptogenic polyneuropathy (77 men and 37 women) and 227 referents (110 men and 117 women) randomly selected from the population registry. None had any current occupational exposure to n-hexane or MBK. The urine samples were analysed by a gas chromatographic method based on acidic hydrolysis. Results Cases had statistically higher urinary levels of 2,5-HD (0.48 mg/L) than the general population (0.41 mg/L) and men higher excretion than women (0.48 mg/L and 0.38 mg/L, respectively). There was no difference in 2,5-HD levels between current smokers and non-smokers. Occupational exposure to xylene, alcohol consumption and ever exposed to general anaesthesia were associated with lower excretion in men while for occupational exposure to nitrous oxide in women higher excretion was seen. Higher excretion of 2,5 HD was inversely related to increasing age. Conclusions Significantly higher levels of urinary 2,5-HD were seen in men and cryptogenic polyneuropathy cases seemingly unexposed to n-hexane. Hypothetically, this might be due to either differences in metabolic patterns or some concealed exposure. The difference in means between cases and the general population is small and can therefore not allow any firm conclusions of the causality, however. PMID:23898939

Urinary excretion levels of water-soluble vitamins in pregnant and lactating women in Japan.

PubMed

Shibata, Katsumi; Fukuwatari, Tsutomu; Sasaki, Satoshi; Sano, Mitsue; Suzuki, Kahoru; Hiratsuka, Chiaki; Aoki, Asami; Nagai, Chiharu

2013-01-01

Recent studies have shown that the urinary excretion levels of water-soluble vitamins can be used as biomarkers for the nutritional status of these vitamins. To determine changes in the urinary excretion levels of water-soluble vitamins during pregnant and lactating stages, we surveyed and compared levels of nine water-soluble vitamins in control (non-pregnant and non-lactating women), pregnant and lactating women. Control women (n=37), women in the 2nd (16-27 wk, n=24) and 3rd trimester of pregnancy (over 28 wk, n=32), and early- (0-5 mo, n=54) and late-stage lactating (6-11 mo, n=49) women took part in the survey. The mean age of subjects was ~30 y, and mean height was ~160 cm. A single 24-h urine sample was collected 1 d after the completion of a validated, self-administered comprehensive diet history questionnaire to measure water-soluble vitamins or metabolites. The average intake of each water-soluble vitamin was ≍ the estimated average requirement value and adequate intake for the Japanese Dietary Reference Intakes in all life stages, except for vitamin B6 and folate intakes during pregnancy. No change was observed in the urinary excretion levels of vitamin B2, vitamin B6, vitamin B12, biotin or vitamin C among stages. Urine nicotinamide and folate levels were higher in pregnant women than in control women. Urine excretion level of vitamin B1 decreased during lactation and that of pantothenic acid decreased during pregnancy and lactation. These results provide valuable information for setting the Dietary Reference Intakes of water-soluble vitamins for pregnant and lactating women.

Relevance of dietary protein concentration and quality as risk factors for the formation of calcium oxalate stones in cats.

PubMed

Paßlack, Nadine; Burmeier, Hannes; Brenten, Thomas; Neumann, Konrad; Zentek, Jürgen

2014-01-01

The role of dietary protein for the development of feline calcium oxalate (CaOx) uroliths has not been conclusively clarified. The present study evaluated the effects of a varying dietary protein concentration and quality on critical indices for the formation of CaOx uroliths. Three diets with a high protein quality (10-11 % greaves meal/diet) and a varying crude protein (CP) concentration (35, 44 and 57 % in DM) were compared. Additionally, the 57 % CP diet was compared with a fourth diet that had a similar CP concentration (55 % in DM), but a lower protein quality (34 % greaves meal/diet). The Ca and oxalate (Ox) concentrations were similar in all diets. A group of eight cats received the same diet at the same time. Each feeding period was divided into a 21 d adaptation period and a 7 d sampling period to collect urine. There were increases in urinary volume, urinary Ca concentrations, renal Ca and Ox excretion and urinary relative supersaturation (RSS) with CaOx with increasing dietary protein concentrations. Urinary pH ranged between 6·34 and 6·66 among all groups, with no unidirectional effect of dietary protein. Lower renal Ca excretion was observed when feeding the diet with the lower protein quality, however, the underlying mechanism needs further evaluation. In conclusion, although the observed higher urinary volume is beneficial, the increase in urinary Ca concentrations, renal Ca and Ox excretion and urinary RSS CaOx associated with a high-protein diet may be critical for the development of CaOx uroliths in cats.

Circadian rhythm of blood pressure and the renin-angiotensin system in the kidney.

PubMed

Ohashi, Naro; Isobe, Shinsuke; Ishigaki, Sayaka; Yasuda, Hideo

2017-05-01

Activation of the intrarenal renin-angiotensin system (RAS) has a critical role in the pathophysiology of the circadian rhythm of blood pressure (BP) and renal injury, independent of circulating RAS. Although it is clear that the circulating RAS has a circadian rhythm, reports of a circadian rhythm in tissue-specific RAS are limited. Clinical studies evaluating intrarenal RAS activity by urinary angiotensinogen (AGT) levels have indicated that urinary AGT levels were equally low during both the daytime and nighttime in individuals without chronic kidney disease (CKD) and that urinary AGT levels were higher during the daytime than at nighttime in patients with CKD. Moreover, urinary AGT levels of the night-to-day (N/D) ratio of urinary AGT were positively correlated with the levels of N/D of urinary protein, albumin excretion and BP. In addition, animal studies have demonstrated that the expression of intrarenal RAS components, such as AGT, angiotensin II (AngII) and AngII type 1 receptor proteins, increased and peaked at the same time as BP and urinary protein excretion during the resting phase, and the amplitude of the oscillations of these proteins was augmented in a chronic progressive nephritis animal compared with a control. Thus, the circadian rhythm of intrarenal RAS activation may lead to renal damage and hypertension, which both are associated with diurnal variations in BP. It is possible that augmented glomerular permeability increases AGT excretion levels into the tubular lumen and that circadian fluctuation of glomerular permeability influences the circadian rhythm of the intrarenal RAS.

A pilot study of the effect of human breast milk on urinary metabolome analysis in infants.

PubMed

Shoji, Hiromichi; Taka, Hikari; Kaga, Naoko; Ikeda, Naho; Kitamura, Tomohiro; Miura, Yoshiki; Shimizu, Toshiaki

2017-08-28

This study aimed to examine the nutritional effect of breast feeding on healthy term infants by using urinary metabolome analysis. Urine samples were collected from 19 and 14 infants at 1 and 6 months, respectively. Infants were separated into two groups: the breast-fed group receiving <540 mL/week of their intake from formula (n=13 at 1 month; n=9 at 6 months); and the formula-fed group receiving no breast milk (BM) (n=6 at 1 month; n=5 at 6 months). Urinary metabolome analysis was performed using capillary electrophoresis-time-of-flight mass spectrometry (CE-TOF/MS). A total of 29 metabolites were detected by CE-TOF/MS metabolome analysis in all samples. Urinary excretion of choline metabolites (choline base solution, N,N-dimethylglycine, sarcosine, and betaine) at 1 month were significantly (p<0.05) higher in breast-fed infants than in formula-fed infants. However, choline metabolites were not significantly different between the groups at 6 months. Urinary excretion of lactic acid in breast-fed infants at 1 and 6 months was significantly lower than that in formula-fed infants. Urinary l(-)-threonine and l-carnosine excretion at 1 month was significantly lower in breast-fed infants than in formula-fed infants, but it was not significantly different between the groups at 6 months. The type of feeding in early infancy affects choline metabolism, as well as lactate, threonine, and carnosine levels, in healthy term infants. Urinary metabolome analysis by the CE-TOF/MS method is useful for assessing nutritional metabolism in infants.

The effect of aliskiren on urinary cytokine/chemokine responses to clamped hyperglycaemia in type 1 diabetes.

PubMed

Cherney, David Z I; Reich, Heather N; Scholey, James W; Daneman, Denis; Mahmud, Farid H; Har, Ronnie L H; Sochett, Etienne B

2013-10-01

Acute clamped hyperglycaemia activates the renin-angiotensin-aldosterone system (RAAS) and increases the urinary excretion of inflammatory cytokines/chemokines in patients with uncomplicated type 1 diabetes mellitus. Our objective was to determine whether blockade of the RAAS would blunt the effect of acute hyperglycaemia on urinary cytokine/chemokine excretion, thereby giving insights into potentially protective effects of these agents prior to the onset of clinical nephropathy. Blood pressure, renal haemodynamic function (inulin and para-aminohippurate clearances) and urinary cytokines/chemokines were measured after 6 h of clamped euglycaemia (4-6 mmol/l) and hyperglycaemia (9-11 mmol/l) on two consecutive days in patients with type 1 diabetes mellitus (n = 27) without overt nephropathy. Measurements were repeated after treatment with aliskiren (300 mg daily) for 30 days. Before aliskiren, clamped hyperglycaemia increased filtration fraction (from 0.188 ± 0.007 to 0.206 ± 0.007, p = 0.003) and urinary fibroblast growth factor-2 (FGF2), IFN-α2 and macrophage-derived chemokine (MDC) (p < 0.005). After aliskiren, the filtration fraction response to hyperglycaemia was abolished, resulting in a lower filtration fraction after aliskiren under clamped hyperglycaemic conditions (p = 0.004), and none of the biomarkers increased in response to hyperglycaemia. Aliskiren therapy also reduced levels of urinary eotaxin, FGF2, IFN-α2, IL-2 and MDC during clamped hyperglycaemia (p < 0.005). The increased urinary excretion of inflammatory cytokines/chemokines in response to acute hyperglycaemia is blunted by RAAS blockade in humans with uncomplicated type 1 diabetes mellitus.

Urinary excretion values in 2-day food-deprived, unrestrained chimpanzees.

NASA Technical Reports Server (NTRS)

Mcnew, J. J.; Sabbot, I. M.; Hoshizaki, T.; Mandell, A. J.; Spooner, C. E.; Marcus, I.; Adey, W. R.

1972-01-01

A study was conducted to determine the baseline 24-hr urinary excretion values in the young, unrestrained chimpanzee, and also changes in urinary values, if any, induced by the two-day food deprivation stress. Urine was analyzed for volume, osmolarity, creatinine, creatine, urea nitrogen, 17-hydroxycorticosteroids (17-OHCS), 3-methoxy-4-hydroxymandelic acid (VMA), calcium, and inorganic phosphorus. Significant increases due to food deprivation stress were observed for volume, creatine, urea nitrogen, 17-OHCS, VMA, and phosphorus values, with significant decreases in osmolarity and calcium. All values approached normal levels by the second poststress day. No significant changes were observed in creatinine. A comparison is drawn between human and chimpanzee adaptation to stress.

76 FR 6335 - Sodium and Potassium Salts of N-alkyl (C8

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-04

...): Solvents such as alcohols and hydrocarbons; surfactants such as polyoxyethylene polymers and fatty acids... metabolites are not systemically toxic and would be rapidly conjugated and excreted. The SSNA surfactants (mono and di-sodium propionates) may be conjugated and excreted directly. Alternatively, the tertiary...

Zea mays L. extracts modify glomerular function and potassium urinary excretion in conscious rats.

PubMed

Velazquez, D V O; Xavier, H S; Batista, J E M; de Castro-Chaves, C

2005-05-01

Diuretic and uricosuric properties have traditionally been attributed to corn silk, stigma/style of Zea mays L. Although the diuretic effect was confirmed, studies of the plant's effects on renal function or solute excretion were lacking. Thus, we studied the effects of corn silk aqueous extract on the urinary excretion of water, Na+, K+, and uric acid. Glomerular and proximal tubular function and Na+ tubular handling were also studied. Conscious, unrestrained adult male rats were housed in individual metabolic cages (IMC) with continuous urine collection for 5 and 3 h, following two protocols. The effects of 25, 50, 200, 350, and 500 mg/kg body wt. corn silk extract on urine volume plus Na+ and K+ excretions were studied in water-loaded conscious rats (2.5 ml/100 g body wt.) in the IMC for 5 h (Protocol 1). Kaliuresis was observed with doses of 350 (100.42 +/- 22.32-120.28 +/- 19.70 microEq/5 h/100 g body wt.; n = 13) and 500 mg/kg body wt. (94.97+/- 29.30-134.32 +/- 39.98 microEq/5h/100 g body wt.; n = 12; p<0.01), and the latter dose resulted in diuresis as well (1.98 +/- 0.44-2.41 +/- 0.41 ml/5 h/100 g body wt.; n = 12; p<0.05). The effects of a 500 mg/kg body wt. dose of corn silk extract on urine volume, Na+, K+ and uric acid excretions, and glomerular and proximal tubular function, were measured respectively by creatinine (Cler) and Li+ (ClLi) clearances and Na+ tubular handling, in water-loaded rats (5 ml/100 g body wt.) in the IMC for 3 h (Protocol 2). Clcr (294.6 +/- 73.2, n = 12, to 241.7 +/- 48.0 microl/ min/100 g body wt.; n = 13; p<0.05) and the Na+ filtered load (41.9 +/- 10.3, n = 12, to 34.3 +/- .8, n = 13, p<0.05) decreased and ClLi and Na+ excretion were unchanged, while K+ excretion (0.1044 +/- 0.0458, n=12, to 0.2289 +/- 0.0583 microEq/min/100 body wt.; n = 13; p<0.001) increased. For Na+ tubular handling, the fractional proximal tubular reabsorption (91.5 +/- 3.5, n = 12, to 87.5 +/- 3.4%; n = 13; p<0.01) decreased, and both fractional distal reabsorptions--I and II--increased (96.5 +/- 1.5, n = 12, to 97.8 +/- 0.9%; n = 13; p<0.01; and 8.2 +/- 3.5, n = 12, to 12.2 +/- 3.4%, n = 13, p<0.01, respectively). To summarize, in water-loaded conscious rats (2.5 ml/100 body wt.), corn silk aqueous extract is diuretic at a dose of 500 mg/kg body wt. and kaliuretic at doses of 350 and 500 mg/kg body wt. In water-loaded conscious rats (5.0 ml/100 g body wt.), corn silk aqueous extract is kaliuretic at a dose of 500 mg/kg body wt., but glomerular filtration and filtered load decrease without affecting proximal tubular function, Na+, or uric acid excretion.

Steroid hormone release as well as renal water and electrolyte excretion of mice expressing PKB/SGK-resistant GSK3.

PubMed

Boini, Krishna M; Bhandaru, Madhuri; Mack, Andreas; Lang, Florian

2008-09-01

Insulin and insulin-like growth factor (IGF1) participate in the regulation of renal electrolyte excretion. Insulin- and IGF1-dependent signaling includes phosphatidylinositide-3 (PI3)-kinase, phosphoinositide-dependent kinase PDK1 as well as protein kinase B (PKB) and serum and glucocorticoid inducible kinase (SGK) isoforms, which in turn phosphorylate and thus inhibit glycogen synthase kinase GSK3alpha,beta. Replacement of the serines in the PKB/SGK consensus sequences by alanine (gsk3 ( KI )) confers resistance of GSK3 to PKB/SGK. To explore the role of PKB/SGK-dependent inhibition of GSK3 in the regulation of water/electrolyte metabolism, mice carrying the PKB/SGK resistant mutant (gsk3 ( KI )) were compared to their wild-type littermates (gsk3 ( WT ) ). Body weight was similar in gsk3 ( KI ) and gsk3 ( WT ) mice. Plasma aldosterone at 10 A.M: . and corticosterone concentrations at 5 P.M: . were significantly lower, but 24-h urinary aldosterone was significantly higher, and corticosterone excretion tended to be higher in gsk3 ( KI ) than in gsk3 ( WT ) mice. Food and water intake, fecal excretion, glomerular filtration rate, urinary flow rate, urine osmolarity, as well as urinary Na+, K+, urea excretion were significantly larger, and plasma Na+, urea, but not K+ concentration, were significantly lower in gsk3 ( KI ) than in gsk3 ( WT ) mice. Body temperature was significantly higher in gsk3 ( KI ) than in gsk3 ( WT ) mice. When allowed to choose between tap water and saline, gsk3 ( WT ) mice drank more saline, whereas gsk3 ( KI ) mice drank similar large volumes of tap water and saline. During high-salt diet, urinary vasopressin excretion increased to significantly higher levels in gsk3 ( KI ) than in gsk3 ( WT ) mice. After water deprivation, body weight decreased faster in gsk3 ( KI ) than in gsk3 ( WT ) mice. Blood pressure, however, was significantly higher in gsk3 ( KI ) than in gsk3 ( WT ) mice. The observations disclose a role of PKB/SGK-dependent GSK3 activity in the regulation of steroid hormone release, renal water and electrolyte excretion and blood pressure control.

Correlation of arsenic exposure through drinking groundwater and urinary arsenic excretion among adults in Pakistan.

PubMed

Ahmed, Mubashir; Fatmi, Zafar; Ali, Arif

2014-01-01

Long-term exposure to arsenic has been associated with manifestation of skin lesions (melanosis/keratosis) and increased risk of internal cancers (lung/bladder). The objective of the study described here was to determine the relationship between exposure of arsenic through drinking groundwater and urinary arsenic excretion among adults > or =15 years of age living in Khairpur district, Pakistan. Total arsenic was determined in drinking groundwater and in spot urine samples of 465 randomly selected individuals through hydride generation-atomic absorption spectrometry. Spearman's rank correlation coefficient was calculated between arsenic in drinking groundwater and arsenic excreted in urine. The median arsenic concentration in drinking water was 2.1 microg/L (range: 0.1-350), and in urine was 28.5 microg/L (range: 0.1-848). Positive correlation was found between total arsenic in drinking water and in urine (r = .52, p < .01). Urinary arsenic may be used as a biomarker of arsenic exposure through drinking water.

Effects of enviromental temperature and femoral fracture on wound healing in rats.

PubMed

Crowley, L V; Seifter, E; Kriss, P; Rettura, G; Nakao, K; Levenson, S M

1977-06-01

Femoral fracture, unilateral and bilateral, impaired the healing of dorsal skin incisions and formation of reparative granulation tissue in subcutaneously implanted polyvinyl alcohol sponges judged histologically and by breaking strengths and hydroxyproline contents, respectively, 1 week after injury in pair-fed rats kept at 22 degrees C. When rats were transferred to a room at 30 degrees C immediately after skin incision and sponge implants, with or without unilateral fracture, no differences in healing were observed between the two groups. Rats with skin incision, sponge implants, and either femoral fracture or sham-fracture excreted more urinary nitrogen than preoperatively when kept at 22 degrees. Counterpart groups transferred to a 30 degrees room right after operation excreted less urinary nitrogen than preoperatively, but because of lower food intakes postoperatively, the ratio of urinary nitrogen to food intake nitrogen was increased. With equivalent food intakes, pair-fed rats with fracture kept at 22 degrees postoperatively lost more weight and excreted more nitrogen than corresponding rats transfered to a 30 degrees room.

Behavior of Americium in Simulated Wounds in Nonhuman Primates

DOE PAGES

Poudel, Deepesh; Guilmette, Raymond A.; Bertelli, Luiz; ...

2017-06-01

An americium solution injected intramuscularly into several nonhuman primates (NHPs) was found to behave differently than predicted by the wound models described in the NCRP Report 156. This was because the injection was made along with a citrate solution, which is known to be more soluble than chlorides, oxides, or nitrates on which the NCRP Report was based. We developed a multi-exponential wound model specific to the injected americium solution based on the retention in the intramuscular sites. The model was coupled with the americium systemic model to interpret the urinary excretion data and assess the intake, and it wasmore » determined that the models were adequate to predict early urinary excretion in most cases but unable to predict late urinary excretion. This was attributed to the differences in the systemic handling of americium between humans and nonhuman primates. Furthermore, information on the type of wounds, solubility, particle size, mass, chemical form, etc., should always be considered when performing wound dosimetry.« less

Severe metabolic alkalosis, hypokalemia, and respiratory acidosis induced by the Chinese herbal medicine yokukansan in an elderly patient with muscle weakness and drowsiness.

PubMed

Yamada, Shunsuke; Tokumoto, Masanori; Kansui, Yasuo; Wakisaka, Yoshinobu; Uchizono, Yuji; Tsuruya, Kazuhiko; Ooboshi, Hiroaki

2013-05-01

Yokukansan is a Chinese herbal medicine containing licorice that has been shown to alleviate the behavioral and psychological symptoms of Alzheimer's disease, with few adverse effects. Increasing numbers of patients with Alzheimer's disease in Japan are now being treated with this drug. However, yokukansan should be used with caution because of its potential to induce pseudoaldosteronism through the inhibition of 11-beta-hydroxysteroid dehydrogenase type 2, which metabolizes cortisol into cortisone. We present the case of an 88-year-old woman with a history of Alzheimer's disease who was transferred to our emergency department because of drowsiness, anorexia, and muscle weakness. Her blood pressure was 168/90 mmHg. Laboratory data showed serum potassium of 1.9 mmol/l, metabolic alkalosis (pH 7.54; HCO 3 - , 50.5 mmol/l; chloride, 81 mmol/l; sodium, 140 mmol/l), and respiratory disorders (pCO 2 , 60.5 mmHg; pO 2 , 63.8 mmHg). Plasma renin activity and aldosterone concentration were suppressed, and urinary potassium excretion was 22 mmol/l (calculated transtubular potassium gradient 12.9). An electrocardiogram showed flat T-waves and U-waves with ventricular premature contractions. Echocardiography denied volume depletion. Medical interview disclosed that she had been treated with a Chinese herbal medicine (yokukansan) containing licorice. The final diagnosis was pseudoaldosteronism and respiratory acidosis induced by licorice. Hypokalemia, metabolic alkalosis, and respiratory acidosis all subsided shortly after the discontinuation of yokukansan and initiation of intravenous potassium replacement. This case highlights the need for nephrologists to consider the possible involvement of Chinese herbal medicines, including yokukansan, when they encounter hypokalemia in elderly patients.

Potassium intake and risk of incident type 2 diabetes mellitus: the Coronary Artery Risk Development in Young Adults (CARDIA) Study

PubMed Central

Colangelo, L. A.; Yeh, H. C.; Anderson, C. A.; Daviglus, M. L.; Liu, K.; Brancati, F. L.

2014-01-01

Aims/hypothesis Serum potassium has been found to be a significant predictor of diabetes risk, but the effect of dietary potassium on diabetes risk is not clear. We sought to determine if dietary potassium is associated with risk of incident type 2 diabetes in young adults. Methods We used data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Potassium intake was measured by (1) an average of three 24 h urinary potassium collections at the 5-year study visit, and (2) the CARDIA dietary assessment instrument at baseline. Incident type 2 diabetes cases were ascertained on the basis of use of diabetes medication and laboratory measurements. Analyses were adjusted for relevant confounders including intake of fruit and vegetables and other dietary factors. Results Of 1,066 participants with urinary potassium measurements, 99 (9.3%) developed diabetes over 15 years of follow-up. In multivariate models, adults in the lowest urinary potassium quintile were more than twice as likely to develop diabetes as their counterparts in the highest quintile (HR 2.45; 95% CI 1.08, 5.59). Of 4,754 participants with dietary history measurements, 373 (7.8%) developed diabetes over 20 years of follow-up. In multivariate models, African-Americans had a significantly increased risk of diabetes with lower potassium intake, which was not found in whites. Conclusions/interpretation Low dietary potassium is associated with increased risk of incident diabetes in African-Americans. Randomised clinical trials are needed to determine if potassium supplementation, from either dietary or pharmacological sources, could reduce the risk of diabetes, particularly in higher-risk populations. PMID:22322920

Possible potassium chlorate nephrotoxicity associated with chronic matchstick ingestion.

PubMed

Thurlow, John S; Little, Dustin J; Baker, Thomas P; Yuan, Christina M

2013-06-01

We present a case of a 48-year-old active duty male soldier with a history of chronic exposure to potassium chlorate, later diagnosed with chronic interstitial nephritis. He reported regular matchstick consumption to prevent chigger (Trombicula autumnalis) bites, amounting to ∼5.8 g of potassium chlorate over 3 years. Potassium chlorate can cause anuric renal failure within days of a toxic dose. Its slow excretion and mechanism of action suggest that renal toxicity may result from lower-dose chronic exposure. This case represents possible sequelae of chronic potassium chlorate ingestion.

Possible potassium chlorate nephrotoxicity associated with chronic matchstick ingestion*

PubMed Central

Thurlow, John S.; Little, Dustin J.; Baker, Thomas P.; Yuan, Christina M.

2013-01-01

We present a case of a 48-year-old active duty male soldier with a history of chronic exposure to potassium chlorate, later diagnosed with chronic interstitial nephritis. He reported regular matchstick consumption to prevent chigger (Trombicula autumnalis) bites, amounting to ∼5.8 g of potassium chlorate over 3 years. Potassium chlorate can cause anuric renal failure within days of a toxic dose. Its slow excretion and mechanism of action suggest that renal toxicity may result from lower-dose chronic exposure. This case represents possible sequelae of chronic potassium chlorate ingestion. PMID:26064493

Proximal tubule glutamine synthetase expression is necessary for the normal response to dietary protein restriction.

PubMed

Lee, Hyun-Wook; Osis, Gunars; Handlogten, Mary E; Verlander, Jill W; Weiner, I David

2017-07-01

Dietary protein restriction has multiple benefits in kidney disease. Because protein intake is a major determinant of endogenous acid production, it is important that net acid excretion changes in parallel during changes in dietary protein intake. Dietary protein restriction decreases endogenous acid production and decreases urinary ammonia excretion, a major component of net acid excretion. Glutamine synthetase (GS) catalyzes the reaction of [Formula: see text] and glutamate, which regenerates the essential amino acid glutamine and decreases net ammonia generation. Because renal proximal tubule GS expression increases during dietary protein restriction, this could contribute to the decreased ammonia excretion. The purpose of the current study was to determine the role of proximal tubule GS in the renal response to protein restriction. We generated mice with proximal tubule-specific GS deletion (PT-GS-KO) using Cre-loxP techniques. Cre-negative (Control) and PT-GS-KO mice in metabolic cages were provided 20% protein diet for 2 days and were then changed to low-protein (6%) diet for the next 7 days. Additional PT-GS-KO mice were maintained on 20% protein diet. Dietary protein restriction caused a rapid decrease in urinary ammonia excretion in both genotypes, but PT-GS-KO blunted this adaptive response significantly. This occurred despite no significant genotype-dependent differences in urinary pH or in serum electrolytes. There were no significant differences between Control and PT-GS-KO mice in expression of multiple other proteins involved in renal ammonia handling. We conclude that proximal tubule GS expression is necessary for the appropriate decrease in ammonia excretion during dietary protein restriction.

Urinary isoflavone excretion as a compliance measure in a soy intervention among young girls: a pilot study

PubMed Central

Maskarinec, G; Oshiro, C; Morimoto, Y; Hebshi, S; Novotny, R; Franke, AA

2006-01-01

Objective To investigate the compliance of young girls with a soy intervention. Design An 8-week dietary intervention and urine sample collection. Setting Free-living girls. Subjects A convenience sample of 8-to 14-y-old girls (20 started and 17 finished the study) recruited through flyers distributed to staff members and previous study participants. Intervention The girls consumed one daily serving of soymilk, soy nuts, or tofu, completed 3-day food records, kept daily soy intake logs, and collected weekly urine samples. Main outcome measures Compliance with the intervention was evaluated by daily soy intake logs, 3-day food records analyzed by the center’s Food Composition and Food Groups Servings Databases, and weekly urinary isoflavone excretion using high-pressure liquid chromatography. The statistical analysis included paired t-tests, analysis of variance, and Spearman’s rank-order correlation coefficients. Results Daily soy intake logs indicated a mean intake of 6.28 servings out of a maximum of 7.0 servings per week. The food records revealed a six-fold increase in isoflavone intake during the study period (P < 0.01) which was confirmed by an increase in urinary isoflavone excretion of similar magnitude (23.3–142.1 nmol/mg creatinine, P = 0.02). Conclusions This study demonstrated the ability of young girls to consume one daily soy serving and the usefulness of urinary isoflavones as a primary compliance measure. The high urinary isoflavone excretion levels detected in girls as compared to adult women suggest less intestinal degradation and/or greater absorption of isoflavones in nonadult populations. This finding requires further investigations into the pharmacokinetics of isoflavones. PMID:15523482

Effect of urban traffic, individual habits, and genetic polymorphisms on background urinary 1-hydroxypyrene excretion.

PubMed

Cocco, Pierluigi; Moore, Patrick S; Ennas, Maria G; Tocco, Maria G; Ibba, Antonio; Mattuzzi, Silvia; Meloni, Michele; Monne, Maria; Piras, Giovanna; Collu, Stefania; Satta, Giannina; Zucca, Mariagrazia; Scarpa, Aldo; Flore, Costantino

2007-01-01

Potential sources of exposure to polycyclic aromatic hydrocarbons (PAHs) and genetic polymorphisms were investigated in relation to their contribution to interindividual variation in baseline levels of urinary 1-hydroxypyrene (1-OHP) excretion in subjects without occupational exposure to PAHs. Urinary excretion of 1-OHP was measured in 114 subjects, including 48 women and 66 men. Questionnaire information was collected on possible environmental and individual sources of PAH exposure. A subset of 70 individuals also was evaluated for a single-nucleotide polymorphism (Ex7+295C-->T) in the cytochrome P-450 1A2 (CYP1A2) gene, and 61 of these also were evaluated for the glutathione transferase T1 (GSTT1) gene polymorphism. 1-OHP values did not show a significant seasonal variability and were unaffected by age; education; body mass index; smoking status, including passive smoking; or the C-->T base substitution in position 295 of exon 7 of the CYP1A2 gene. After reciprocal adjustment with logistic regression, living in a heavily trafficked urban area (odds ratio, 4.9; 95% confidence interval, 1.0-24.9), and frequent intake of grilled meat (odds ratio, 6.9; 95% confidence interval, 1.1-43.5) were significant predictors of background urinary 1-OHP levels of 0.50 microg/g creatinine or greater. Elevated risks also were associated with daily alcohol intake greater than 65 g and the nonnull GSTT1 genotype. Our study shows that exposure to urban traffic, dietary habits, and the nonnull GSTT1 genotype may contribute to interindividual variation in background levels of 1-OHP urinary excretion in subjects without occupational exposure to PAHs.

Renal excretion of water-soluble contrast media after enema in the neonatal period.

PubMed

Kim, Hee Sun; Je, Bo-Kyung; Cha, Sang Hoon; Choi, Byung Min; Lee, Ki Yeol; Lee, Seung Hwa

2014-08-01

When abdominal distention occurs or bowel obstruction is suspected in the neonatal period, a water-soluble contrast enema is helpful for diagnostic and therapeutic purposes. The water-soluble contrast medium is evacuated through the anus as well as excreted via the kidneys in some babies. This study was designed to evaluate the incidence of renal excretion after enemas using water-soluble contrast media and presume the causes. Contrast enemas using diluted water-soluble contrast media were performed in 23 patients under 2 months of age. After the enema, patients were followed with simple abdominal radiographs to assess the improvement in bowel distention, and we could also detect the presence of renal excretion of contrast media on the radiographs. Reviewing the medical records and imaging studies, including enemas and consecutive abdominal radiographs, we evaluated the incidence of renal excretion of water-soluble contrast media and counted the stay duration of contrast media in urinary tract, bladder, and colon. Among 23 patients, 12 patients (52%) experienced the renal excretion of water-soluble contrast media. In these patients, stay-in-bladder durations of contrast media were 1-3 days and stay-in-colon durations of contrast media were 1-10 days, while stay-in-colon durations of contrast media were 1-3 days in the patients not showing renal excretion of contrast media. The Mann-Whitney test for stay-in-colon durations demonstrated the later evacuation of contrast media in the patients with renal excretion of contrast media (p = 0.07). The review of the medical records showed that 19 patients were finally diagnosed as intestinal diseases, including Hirschsprung's disease, meconium ileum, meconium plug syndrome, and small bowel atresia or stenosis. Fisher's exact test between the presence of urinary excretion and intestinal diseases indicated a statistically significant difference (p = 0.04). The intestinal diseases causing bowel obstruction may increase the water-soluble contrast media's dwell time in the bowel and also increase urinary excretion. Copyright © 2013. Published by Elsevier B.V.

Influence of a low- and a high-oxalate vegetarian diet on intestinal oxalate absorption and urinary excretion.

PubMed

Thomas, E; von Unruh, G E; Hesse, A

2008-09-01

To compare quantitatively the effect of a low- and a high-oxalate vegetarian diet on intestinal oxalate absorption and urinary excretion. Eight healthy volunteers (three men and five women, mean age 28.6+/-6.3) were studied. Each volunteer performed the [(13)C(2)]oxalate absorption test thrice on a low-oxalate mixed diet, thrice on a low-oxalate vegetarian diet and thrice on a high-oxalate vegetarian diet. For each test, the volunteers had to adhere to an identical diet and collect their 24-h urines. In the morning of the second day, a capsule containing [(13)C(2)]oxalate was ingested. On the low-oxalate vegetarian diet, mean intestinal oxalate absorption and urinary oxalate excretion increased significantly to 15.8+/-2.9% (P=0.012) and 0.414+/-0.126 mmol/day (P=0.012), compared to the mixed diet. On the high-oxalate vegetarian diet, oxalate absorption (12.5+/-4.6%, P=0.161) and urinary excretion (0.340+/-0.077 mmol/day, P=0.093) did not change significantly, compared to the mixed diet. A vegetarian diet can only be recommended for calcium oxalate stone patients, if the diet (1) contains the recommended amounts of divalent cations such as calcium and its timing of ingestion to a meal rich in oxalate is considered and (2) excludes foodstuffs with a high content of nutritional factors, such as phytic acid, which are able to chelate calcium.

Intrarenal urea recycling leads to a higher rate of renal excretion of potassium: an hypothesis with clinical implications.

PubMed

Kamel, Kamel S; Halperin, Mitchell L

2011-09-01

This review aims to illustrate why urea recycling may play an important role in potassium (K⁺) excretion and to emphasize its potential clinical implications. A quantitative analysis of the process of intrarenal urea recycling reveals that the amount of urea delivered to the distal convoluted tubule is about two-fold larger than the quantity of urea excreted in the urine. As the number of osmoles delivered to the late cortical distal nephron (CCD) determines its flow rate when aquaporin 2 water channels have been inserted in the luminal membrane of principal cells, urea recycling may play an important role in regulating the rate of excretion of K⁺ when the distal delivery of electrolytes is not very high. Urea recycling aids the excretion of K⁺; this is especially important in patients with disorders or those who are taking drugs that lead to a less lumen-negative voltage in the CCD. As a large quantity of urea is reabsorbed daily in the inner medullary collecting duct, the assumption made in the calculation of the transtubular K concentration gradient that there is no appreciable reabsorption of osmoles downstream CCD is not valid.

Humans seem to produce arsenobetaine and dimethylarsinate after a bolus dose of seafood.

PubMed

Molin, M; Ulven, S M; Dahl, L; Telle-Hansen, V H; Holck, M; Skjegstad, G; Ledsaak, O; Sloth, J J; Goessler, W; Oshaug, A; Alexander, J; Fliegel, D; Ydersbond, T A; Meltzer, H M

2012-01-01

Seafood is the predominant food source of several organoarsenic compounds. Some seafood species, like crustaceans and seaweed, also contain inorganic arsenic (iAs), a well-known toxicant. It is unclear whether human biotransformation of ingested organoarsenicals from seafood result in formation of arsenicals of health concern. The present controlled dietary study examined the urinary excretion of arsenic compounds (total arsenic (tAs), iAs, AB (arsenobetaine), dimethylarsinate (DMA) and methylarsonate (MA)) following ingestion of a single test meal of seafood (cod, 780 μg tAs, farmed salmon, 290 μg tAs or blue mussel, 690 μg tAs or potato (control, 110 μg tAs)) in 38 volunteers. The amount of ingested tAs excreted via the urine within 0-72 h varied significantly among the groups: Cod, 74% (52-92%), salmon 56% (46-82%), blue mussel 49% (37-78%), control 45% (30-60%). The estimated total urinary excretion of AB was higher than the amount of ingested AB in the blue mussel group (112%) and also ingestion of cod seemed to result in more AB, indicating possible endogenous formation of AB from other organoarsenicals. Excretion of iAs was lower than ingested (13-22% of the ingested iAs was excreted in the different groups). Although the ingested amount of iAs+DMA+MA was low for all seafood groups (1.2-4.5% of tAs ingested), the urinary DMA excretion was high in the blue mussel and salmon groups, counting for 25% and 11% of the excreted tAs respectively. In conclusion our data indicate a possible formation of AB as a result of biotransformation of other organic arsenicals. The considerable amount of DMA excreted is probably not only due to methylation of ingested iAs, but due to biotransformation of organoarsenicals making it an inappropriate biomarker of iAs exposure in populations with a high seafood intake. Copyright © 2011 Elsevier Inc. All rights reserved.

The urinary excretion of assayable vitamin B12 and radioactivity after parenteral 58Co B12 in man

PubMed Central

Adams, J. F.

1961-01-01

Evidence is presented that after injection of radioactive vitamin B12 in man, there is a close correlation between the amount of radioactivity excreted and the amount of assayable vitamin B12 excreted, and thus that the amount of radioactivity excreted is a true measure of the vitamin B12 excreted. The possible reasons for this occurrence are discussed and it is suggested that in the body vitamin B12 does not exist as such but as an analogue or active derivative. PMID:13681399

Night-rest urinary catecholamine excretion in relation to aspects of free time, work and background data in a teacher group.

PubMed

Kinnunen, U; Vihko, V

1991-01-01

Free time, work and background data were related to night-rest catecholamine excretion rates in a teacher group (n = 137) during an autumn term. The explained interindividual variance increased slightly towards the end of the term. Adrenaline excretion was predicted better than noradrenaline, notedly by coffee consumption, amount of physical activity, and subjective stress feelings which explained 16% of the variance in adrenaline excretion during night rest. However, the results indicated that the differences in catecholamine excretion during night rest remained mostly unpredictable.

Relationship between Sodium Intake and Water Intake: The False and the True.

PubMed

Bankir, Lise; Perucca, Julie; Norsk, Peter; Bouby, Nadine; Damgaard, Morten

2017-01-01

Generally, eating salty food items increases thirst. Thirst is also stimulated by the experimental infusion of hypertonic saline. But, in steady state, does the kidney need a higher amount of water to excrete sodium on a high than on a low sodium intake? This issue is still controversial. The purpose of this review is to provide examples of how the kidney handles water in relation to salt intake/output. It is based on re-analysis of previously published studies in which salt intake was adjusted to several different levels in the same subjects, and in databases of epidemiologic studies in populations on an ad libitum diet. Summary and Key Messages: These re-analyses allow us to draw the following conclusions: (1) In a steady state situation, the urine volume (and thus the fluid intake) remains unchanged over a large range of sodium intakes. The adaptation to a higher sodium excretion rests only on changes in urinary sodium concentration. However, above a certain limit, this concentration cannot increase further and the urine volume may then increase. (2) In population studies, it is not legitimate to assume that sodium is responsible for changes in urine volume, since people who eat more sodium also eat more of other nutrients leading to an increase in the excretion of potassium, urea and other solutes, besides sodium. (3) After an abrupt increase in sodium intake, fluid intake is increased in the first few days, but urine volume does not change. The extra fluid drunk is responsible for an increase in body weight. © 2017 The Author(s) Published by S. Karger AG, Basel.

Gallic acid, a phenolic compound isolated from Mimosa bimucronata (DC.) Kuntze leaves, induces diuresis and saluresis in rats.

PubMed

Schlickmann, Fabile; Boeing, Thaise; Mariano, Luisa Nathália Bolda; da Silva, Rita de Cássia Melo Vilhena de Andrade Fonseca; da Silva, Luisa Mota; de Andrade, Sérgio Faloni; de Souza, Priscila; Cechinel-Filho, Valdir

2018-06-01

Although present in the leaves of Mimosa bimucronata (DC.) and many other medicinal plants commonly used to augment urinary volume excretion, the effects of gallic acid as a diuretic agent remain to be studied. Wistar rats were orally treated with vehicle, hydrochlorothiazide, or gallic acid. The effects of gallic acid in the presence of hydrochlorothiazide, furosemide, amiloride, L-NAME, atropine, and indomethacin were also investigated. Diuretic index, pH, conductivity, and electrolyte excretion were evaluated at the end of the experiment (after 8 or 24 h). Gallic acid induced diuretic and saluretic (Na + and Cl - ) effects, without interfering with K + excretion, when orally given to female and male rats at a dose of 3 mg/kg. These effects were associated with increased creatinine and conductivity values while pH was unaffected by any of the treatments. Plasma Na + , K + , and Cl - levels were not affected by any of the acute treatments. The combination with hydrochlorothiazide or furosemide was unable to intensify the effects of gallic acid when compared with the response obtained with each drug alone. On the other hand, the treatment with amiloride plus gallic acid amplified both diuresis and saluresis, besides to a marked potassium-sparing effect. Its diuretic action was significantly prevented in the presence of indomethacin, a cyclooxygenase inhibitor, but not with the pretreatments with L-NAME or atropine. Although several biological activities have already been described for gallic acid, this is the first study demonstrating its potential as a diuretic agent.

An Intervention with Mineral Water Decreases Cardiometabolic Risk Biomarkers. A Crossover, Randomised, Controlled Trial with Two Mineral Waters in Moderately Hypercholesterolaemic Adults.

PubMed

Toxqui, Laura; Vaquero, M Pilar

2016-06-28

Water intake is essential for health maintenance and disease prevention. The effects of an intervention with two mineral waters, sodium-bicarbonated mineral water (BW) or control mineral water low in mineral content (CW), on cardiometabolic risk biomarkers were studied. In a randomised-controlled crossover-trial, sixty-four moderately hypercholesterolaemic adults were randomly assigned to consume 1 L/day of either BW (sodium, 1 g/L; bicarbonate, 2 g/L) or CW with the main meals for eight weeks, separated by an eight-week washout period. Blood lipids, lipid oxidation, glucose, insulin, aldosterone, urine pH, urinary electrolytes, blood pressure, body weight, fluid intake, energy, and nutrients from total diet and beverages were determined. Total cholesterol, LDL cholesterol, and glucose decreased (p < 0.01), oxidised LDL tended to decrease (p = 0.073), and apolipoprotein B increased during the intervention, without water type effect. Energy and carbohydrates from beverages decreased since soft drinks and fruit juice consumptions decreased throughout the trial. BW increased urinary pH (p = 0.006) and reduced calcium/creatinine excretion (p = 0.011). Urinary potassium/creatinine decreased with both waters. Consumption of 1 L/day of mineral water with the main meals reduces cardiometabolic risk biomarkers, likely to be attributed to a replacement of soft drinks by water. In addition, BW does not affect blood pressure and exerts a moderate alkalizing effect in the body.

Vitamin C modulates lead excretion in rats.

PubMed

Lihm, Hoseob; Kim, Hyun; Chang, Heekyung; Yoon, Myunghee; Lee, Kayoung; Choi, Jongsoon

2013-12-01

Lead, one of the most toxic heavy metals, takes longer time to be excreted from the body than other heavy metals. The purpose of this study is, by measuring lead excretion via urine and feces, to find out the effect of vitamin C in lead chelation. Thirty-six rats were randomly assorted into four groups. All 33 rats except for the control group were administered with lead, before orally administered with different doses of vitamin C per kilogram of body weight. The lead excretion levels in urine and feces as well as the survival rate were then measured for each group. The rats with lead administrations (10/13, 76.9%) with lead administrations only, 10/11 rats (90.9%) with lead administrations and low dose of vitamin C, 9/9 rats (100%) with lead administrations and high dose of vitamin C survived. Among the 29 surviving rats, low vitamin C intake group exhibited higher urinary excretion than the lead only group. The urinary excretion level in high dose vitamin C intakegroup was significantly higher than the lead only group. In addition, fecal lead excretion seemed to be increased in the high dose vitamin C intake group, compared to the group with lead administrations only with statistical significance. Through animal experiment, it was found out that administrating high dose of vitamin C accelerated the excretion of lead in body compared to low dose of vitamin C.

Placing Salt/Soy Sauce at Dining Tables and Out-Of-Home Behavior Are Related to Urinary Sodium Excretion in Japanese Secondary School Students.

PubMed

Okuda, Masayuki; Asakura, Keiko; Sasaki, Satoshi

2017-11-28

We investigated whether home environment, salt knowledge, and salt-use behavior were associated with urinary sodium (Na) excretion in Japanese secondary school students. Students (267; mean age, 14.2 years) from Suo-Oshima, Japan, collected three overnight urine samples and completed a salt environment/knowledge/behavior questionnaire. A subset of students ( n = 66) collected, on non-consecutive days, two 24 h urine samples, and this subset was used to derive a formula for estimating 24 h Na excretion. Generalized linear models were used to examine the association between salt environment/knowledge/behavior and Na excretions. Students that had salt or soy sauce placed on the dining table during meals excreted more Na than those that did not ( p for trend < 0.05). A number of foods to which the students added seasonings were positively associated with Na excretion ( p for trend = 0.005). The students who frequently bought foods at convenience stores or visited restaurants excreted more Na in urine than those who seldom bought foods ( p for trend < 0.05). Knowledge about salt or discretionary seasoning use was not significantly associated with Na excretion. The associations found in this study indicate that home environment and salt-use behavior may be a target for a public health intervention to reduce salt intake of secondary school students.

Placing Salt/Soy Sauce at Dining Tables and Out-Of-Home Behavior Are Related to Urinary Sodium Excretion in Japanese Secondary School Students

PubMed Central

Okuda, Masayuki; Asakura, Keiko; Sasaki, Satoshi

2017-01-01

We investigated whether home environment, salt knowledge, and salt-use behavior were associated with urinary sodium (Na) excretion in Japanese secondary school students. Students (267; mean age, 14.2 years) from Suo-Oshima, Japan, collected three overnight urine samples and completed a salt environment/knowledge/behavior questionnaire. A subset of students (n = 66) collected, on non-consecutive days, two 24 h urine samples, and this subset was used to derive a formula for estimating 24 h Na excretion. Generalized linear models were used to examine the association between salt environment/knowledge/behavior and Na excretions. Students that had salt or soy sauce placed on the dining table during meals excreted more Na than those that did not (pfor trend < 0.05). A number of foods to which the students added seasonings were positively associated with Na excretion (pfor trend = 0.005). The students who frequently bought foods at convenience stores or visited restaurants excreted more Na in urine than those who seldom bought foods (pfor trend < 0.05). Knowledge about salt or discretionary seasoning use was not significantly associated with Na excretion. The associations found in this study indicate that home environment and salt-use behavior may be a target for a public health intervention to reduce salt intake of secondary school students. PMID:29182529

Magnesium and Space Flight

PubMed Central

Smith, Scott M.; Zwart, Sara R.

2015-01-01

Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD) before, during, and after 4–6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female), 35 ± 7 years old). We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4–6-month space missions. PMID:26670248

Magnesium and Space Flight.

PubMed

Smith, Scott M; Zwart, Sara R

2015-12-08

Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD) before, during, and after 4-6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female), 35 ± 7 years old). We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4-6-month space missions.

Effect of vitamin C supplements on urinary oxalate and pH in calcium stone-forming patients.

PubMed

Baxmann, Alessandra Calábria; De O G Mendonça, Claudia; Heilberg, Ita Pfeferman

2003-03-01

The contribution of ascorbate to urinary oxalate is controversial. The present study aimed to determine whether urinary oxalate and pH may be affected by vitamin C supplementation in calcium stone-forming patients. Forty-seven adult calcium stone-forming patients received either 1 g (N=23) or 2 g (N=24) of vitamin C supplement for 3 days and 20 healthy subjects received 1 g. A 24-hour urine sample was obtained both before and after vitamin C for calcium, oxalate, magnesium, citrate, sodium, potassium, and creatinine determination. The Tiselius index was used as a calcium oxalate crystallization index. A spot fasting morning urine sample was also obtained to determine the urinary pH before and after vitamin C. Fasting urinary pH did not change after 1 g (5.8 +/- 0.6 vs. 5.8 +/- 0.7) or 2 g vitamin C (5.8 +/- 0.8 vs. 5.8 +/- 0.7). A significant increase in mean urinary oxalate was observed in calcium stone-forming patients receiving either 1 g (50 +/- 16 vs. 31 +/- 12 mg/24 hours) or 2 g (48 +/- 21 vs. 34 +/- 12 mg/24 hours) of vitamin C and in healthy subjects (25 +/- 12 vs. 39 +/- 13 mg/24 hours). A significant increase in mean Tiselius index was observed in calcium stone-forming patients after 1 g (1.43 +/- 0.70 vs. 0.92 +/- 0.65) or 2 g vitamin C (1.61 +/- 1.05 vs. 0.99 +/- 0.55) and in healthy subjects (1.50 +/- 0.69 vs. 0.91 +/- 0.46). Ancillary analyses of spot urine obtained after vitamin C were performed in 15 control subjects in vessels with or without ethylenediaminetetraacetic acid (EDTA) with no difference in urinary oxalate between them (28 +/- 23 vs. 26 +/- 21 mg/L), suggesting that the in vitro conversion of ascorbate to oxalate did not occur. These data suggest that vitamin C supplementation may increase urinary oxalate excretion and the risk of calcium oxalate crystallization in calcium stone-forming patients.

Effect of Potassium Citrate on Calcium Phosphate Stones in a Model of Hypercalciuria

PubMed Central

Asplin, John R.; Frick, Kevin K.; Granja, Ignacio; Culbertson, Christopher D.; Ng, Adeline; Grynpas, Marc D.; Bushinsky, David A.

2015-01-01

Potassium citrate is prescribed to decrease stone recurrence in patients with calcium nephrolithiasis. Citrate binds intestinal and urine calcium and increases urine pH. Citrate, metabolized to bicarbonate, should decrease calcium excretion by reducing bone resorption and increasing renal calcium reabsorption. However, citrate binding to intestinal calcium may increase absorption and renal excretion of both phosphate and oxalate. Thus, the effect of potassium citrate on urine calcium oxalate and calcium phosphate supersaturation and stone formation is complex and difficult to predict. To study the effects of potassium citrate on urine supersaturation and stone formation, we utilized 95th-generation inbred genetic hypercalciuric stone-forming rats. Rats were fed a fixed amount of a normal calcium (1.2%) diet supplemented with potassium citrate or potassium chloride (each 4 mmol/d) for 18 weeks. Urine was collected at 6, 12, and 18 weeks. At 18 weeks, stone formation was visualized by radiography. Urine citrate, phosphate, oxalate, and pH levels were higher and urine calcium level was lower in rats fed potassium citrate. Furthermore, calcium oxalate and calcium phosphate supersaturation were higher with potassium citrate; however, uric acid supersaturation was lower. Both groups had similar numbers of exclusively calcium phosphate stones. Thus, potassium citrate effectively raises urine citrate levels and lowers urine calcium levels; however, the increases in urine pH, oxalate, and phosphate levels lead to increased calcium oxalate and calcium phosphate supersaturation. Potassium citrate induces complex changes in urine chemistries and resultant supersaturation, which may not be beneficial in preventing calcium phosphate stone formation. PMID:25855777

Effect of fruit on net acid and urinary calcium excretion in an acute feeding trial of women.

PubMed

Bell, Janet Amy; Whiting, Susan Joyce

2004-05-01

Consumption of fruits and vegetables has been implicated in lowering net acid excretion (NAE), but few studies have directly examined NAE and urinary calcium effects. Further, there is no evidence that only fresh fruits and vegetables must be consumed for a beneficial effect on bone. A crossover, acute-load study was designed to investigate whether processed fruit was as effective as fresh fruit in reducing NAE and protein-induced hypercalciuria. Fifteen women completed three dietary treatments on three different mornings. A fasting urine sample was collected before consuming one of the following three isocaloric high-protein treatments: control, fresh apples, and processed applesauce. The serving size for the applesauce treatment was 2.5 times that for fresh apples. Urine was collected at baseline (0 h) and at 1.5, 3.0, and 4.5 h. Compared with baseline, NAE increased after control treatment but decreased after fresh or processed apple treatment (P = 0.041). Calcium excretion increased with all treatments by 3 h; however, the increase was less for fresh apple and applesauce (P = 0.024). In an acute feeding model, fruit intake reduced NAE and urinary calcium excretion. Processed fruit appears to be effective, although a larger serving size was needed than with fresh fruit.

Gluten and casein supplementation does not increase symptoms in children with autism spectrum disorder.

PubMed

Pusponegoro, Hardiono D; Ismael, Sofyan; Firmansyah, Agus; Sastroasmoro, Sudigdo; Vandenplas, Yvan

2015-11-01

A gluten- and casein-free diet is often given to children with autism spectrum disorder (ASD). We aimed to determine the effect of gluten and casein supplementation on maladaptive behaviour, gastrointestinal symptom severity and intestinal fatty acids binding protein (I-FABP) excretion in children with ASD. A randomised, controlled, double-blind trial was performed on 74 children with ASD with severe maladaptive behaviour and increased urinary I-FABP. Subjects were randomised to receive gluten-casein or a placebo for seven days. We evaluated maladaptive behaviour before and after supplementation, using I-FABP excretion, the approach withdrawal problem composite subtest of the Pervasive Developmental Disorder Behavior Inventory and the Gastrointestinal Symptom Severity Index. The mean approach withdrawal problem composite score was significantly higher before supplementation than after, both in the placebo and in the gluten-casein group. However, the mean difference was not significant and may have been caused by additional therapy. There was no significant difference in gastrointestinal symptoms and urinary I-FABP excretion. Administrating gluten-casein to children with ASD for one week did not increase maladaptive behaviour, gastrointestinal symptom severity or urinary I-FABP excretion. The effect of prolonged administration or other mechanisms of enterocyte damage in ASD should be explored. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

DIETARY SODIUM ADHERENCE IS POOR IN CHRONIC HEART FAILURE PATIENTS

PubMed Central

Basuray, Anupam; Dolansky, Mary; Josephson, Richard; Sattar, Abdus; Grady, Ellen M.; Vehovec, Anton; Gunstad, John; Redle, Joseph; Fang, James; Hughes, Joel W.

2015-01-01

Background We sought to determine the rates and predictors of dietary sodium restriction, while evaluating the reliability of the 24-hour urine collection as a tool to estimate dietary sodium intake in heart failure (HF) patients. Methods and Results We evaluated the 24-hour urinary sodium excretion of 305 outpatients with HF and reduced ejection fraction who were educated on following a <2 gm sodium diet. The mean sodium excretion using a single sample from each participant was 3.15 ± 1.58 grams, and 23% were adherent to the <2 gm recommendation. 168 participants provided two samples with urinary creatinine excretion within normative range. Averaging both resulted in a mean sodium excretion of 3.21 ± 1.20 grams and lower adherence rates to the <2-gram diet: 14% versus 23% (p=0.019). Multivariate logistic regression showed only male sex and higher BMI was associated with non-adherence (OR male: 2.20, 95% CI: 1.25-3.88, OR one unit BMI: 1.05, 95% CI: 1.01-1.10). Bland-Altman plots of urinary sodium and creatinine showed poor reproducibility between samples. Conclusions In this chronic HF population, sodium consumption probably exceeds recommended amounts, particularly in men and those with higher BMI. Urine analyses were not highly reproducible, suggesting variation in both diet and urine collection. PMID:25576680

Stress in air traffic controllers : a restudy of 32 controllers 5 to 9 years later.

DOT National Transportation Integrated Search

1978-10-01

Thirty-two subjects who had participated in air traffic controller stress studies 5-9 years earlier were restudied with regard to urinary excretion of 17-ketogenic steroids, epinephrine, and norepinephrine. All subjects showed decreases in excretion ...

ESTIMATES OF AGE-SPECIFIC URINARY EXCRETION RATES FOR CREATININE AMONG CHILDREN

EPA Science Inventory

The results of this study suggest that naïve adjustment by creatinine concentration, without consideration of the age-dependence of the physiological mechanisms controlling its excretion, may introduce sizeable error and is inappropriate when comparing metabolite concentrations a...

Effect of a commercial anion dietary supplement on acid-base balance, urine volume, and urinary ion excretion in male goats fed oat or grass hay diets.

PubMed

Stratton-Phelps, Meri; House, John K

2004-10-01

To determine whether feeding a commercial anionic dietary supplement as a urinary acidifier to male goats may be useful for management of urolithiasis. 8 adult sexually intact male Toggenburg, Saanen, and Nubian goats. Goats were randomly assigned by age-, breed-, and weight-matched pairs to an oat or grass hay diet that was fed for 12 days. On days 13 to 14 (early sample collection time before supplementation), measurements were made of blood and urine sodium, potassium, calcium, magnesium, chloride, phosphorus, and sulfur concentrations; blood and urine pH; urine production; and water consumption. During the next 28 days, the anionic dietary supplement was added to the oat and grass hay diets to achieve a dietary cation-anion difference of 0 mEq/100g of dry matter. Blood and urine samples were analyzed during dietary supplementation on days 12 to 13 (middle sample collection time) and 27 to 28 (late sample collection time). Blood bicarbonate, pH, and urine pH of goats fed grass hay and goats fed oat hay were significantly decreased during the middle and late sample collection times, compared with the early sample collection time. Water consumption and urine production in all goats increased significantly during the late sample collection time, compared with the early sample collection time. The anionic dietary supplement used in our study increases urine volume, alters urine ion concentrations, and is an efficacious urinary acidifier in goats. Goats treated with prolonged anionic dietary supplementation should be monitored for secondary osteoporosis from chronic urinary calcium loss.

Effects of drinking water quality on urinary parameters in men with and without urinary tract stones.

PubMed

Mirzazadeh, Majid; Nouran, Mina Ghadimi; Richards, Kyle A; Zare, Mariam

2012-03-01

There is some controversy regarding the impact of water hardness on stone risk. Our study addresses this issue in a controlled setting. Fifteen stone-former (SF) and 14 non-stone-former (NSF) males participated in this study in 3 intervals of 2 days each. Subjects collected a 24-hour urine sample while consuming a self-selected diet. They were then administered controlled diets. During the first 2 days, patients consumed water of minimal hardness (WMH), followed by tap water (TW) with moderate hardness on days 3 and 4, and mineral water (MW) on the final 2 days. Calcium (Ca), phosphorus, uric acid, oxalate, citrate, magnesium (Mg), sodium, potassium, and creatinine (Cr) content were measured in 24-hour urine samples on days 2, 4, and 6. Differences in water hardness and analytes were statistically significant among the different water types (P < .05). Urinary output in both groups increased during intervention with all 3 varieties of water (P < .05). Specific gravity of urine decreased in both groups drinking WMH and TW (P < .05) but not with MW. Mg/g Cr level was higher in NSF at baseline (P < .01), WMH (P < .05), and TW (P < .05). With the increase in drinking water hardness, Ca/g Cr ratio increased in SF but not in NSF (P < .05). NSF had significantly higher urinary Mg/g Cr excretion rate before intervention than SF (P < .01). Increasing drinking water hardness while controlling for all other factors increased Ca/g Cr ratio in SF, rendering them at least theoretically more inclined to stone formation. Copyright © 2012 Elsevier Inc. All rights reserved.

Renal excretion in coho salmon (Oncorhynchus kisutch) after acute exposure to 3-trifluoromethyl-4-nitrophenol

USGS Publications Warehouse

Hunn, J.B.; Allen, J.L.

1975-01-01

COHO SALMON (ONCORHYNCHUS KISUTCH) EXPOSED TO AN ACUTE, SUBLETHAL CONCENTRATION OF 3-TRIFLUOROMETHLY 1-4 NITROPHENOL (TFM) EXHIBITED AN INCREASED OUTPUT OF URINE WHEN COMPARED WITH CONTROLS, BUT THE URINARY EXCRETION OF NA, K, CA, MG AND C1 WAS NOT AFFECTED. ABOUT 35 TIMES MORE CONJUGATED TFM THAN FREE TFM WAS EXCRETED DURING THE 24-HOUR STUDY PERIOD.

Low blood pressure in vegetarians: the possible role of potassium.

PubMed

Ophir, O; Peer, G; Gilad, J; Blum, M; Aviram, A

1983-05-01

Ninety-eight confirmed adult vegetarians were examined against a matched group of nonvegetarians living in the same urban environment in order to evaluate the prevalence of arterial hypertension. The average blood pressure was 126/77 for the vegetarians and 147/88 for the control group (p less than 0.05). Significantly lower blood pressure was found in every decade of age. Only 2% of the vegetarians had hypertension (higher than 160/95) as compared to 26% hypertensives in the nonvegetarians. These differences in blood pressure were maintained also when individuals with the same "relative weight" were compared. Family history of hypertension was similar in both groups. Analysis of factors such as coffee drinking and smoking did not favor reduced blood pressure among the vegetarian group. Sodium and potassium intake were evaluated from their ratios to creatinine in a single urine sample. It was evident that both groups excreted the same amounts of sodium, while potassium excretion was significantly higher in the vegetarians. In view of the increasing evidence that potassium plays an important role in the regulation of blood pressure it is concluded that the protective antihypertensive factor in the vegetarian diet is the presence of high amounts of potassium.

Potassium status of Northeast Thai constructors in three different geographic locations.

PubMed

Tosukhowong, P; Sriboonlue, P; Tungsanga, K; Bovornpadungkitti, S; Chatuporn, S; Muktahant, B; Prapunwattana, P; Sangwatanaroj, S; Sitprija, V

2001-06-01

Sudden and unexpected death of young adults during sleep is a phenomenon among Southeast Asians and particularly young Northeast (NE) Thailand constructors in Singapore. Survivor of sudden unexplained death syndrome (SUDS) without structural heart disease with idopathic ventricular fibrillation (VF) has been documented. Low plasma potassium (K) and depletion of K can occur simply through a reduction of K intake and are associated with increased risk of VF. The K-status of the populations was evaluated in the NE (Group 1, n=30), Bangkok (Group 2, n=48) and Singapore (Group 3, n=46). Groups 2 and 3 were further subdivided into Group 2A (worked in Bangkok < or = 1 year, n=8), Group 2B (worked in Bangkok > 1 year, n=40), Group 3A (consumed self-prepared or ready-to-buy meals, n=25) and Group 3B (regularly consumed foods provided free-of-charge by construction companies, n=21). Thirty-four male healthy university personnels from the NE and Bangkok served as the control--Group 4. Two 24-h urine samples and a fasting blood sample were collected from each subject. Dietary-K from food was determined by duplicated meal analysis. All these samples were then analyzed for their K-content. Group 3A had the lowest K-status: their K-intake, serum-K, and urinary-K level were 29 +/- 5.8 mmol/day (% low K-intake=100), 3.43 +/- 0.34 mmol/L (% hypokalemia=48) and 19.23 +/- 8.2 mmol/day (% hypokaliuria=87.5), respectively. Among the construction workers, average K-intake, serum-K and urinary-K levels were 45.5 +/- 6.1 mmol/day (% low K-intake = 37.5), 3.93 +/- 0.2 mmol/L (% hypokalemia = 2.5) and 39.6 +/- 9.2 mmol/day (% hypokaliuria = 12.5), respectively. The values of Group 2B were similar to Group 4. In addition, when the data from all of the groups were compared, there was a positive correlation between dietary-K (intake) and urinary-K (excretion) (r=0.881, p<0.001). In conclusion, NE Thailand constructors from various locations exhibited low K status with low dietary-K, high incidence of hypokalemia, and low urinary-K. From the present study, this low K status may be an important trigger factor for VF in construction workers and associated with increase risk of SUDS.

Urinary iodine excretion (UIE) estimated by iodine/creatinine ratio from spot urine in Chinese school-age children.

PubMed

Chen, Wen; Li, Xiang; Guo, Xiaohui; Shen, Jun; Tan, Long; Lin, Laixiang; Wu, Yalan; Wang, Wei; Wang, Wenqiang; Bian, Jianchao; Zhang, Wanqi

2017-04-01

To assess the validity of urinary iodine excretion (UIE) estimated by urinary iodine/creatinine ratio (UI/Cr) from spot urines in Chinese school-age children. A cross-sectional survey was performed in which twice-repeated collections of 24-h urine, and spot urine samples were obtained within 1 month. Urinary iodine concentration (UIC), urinary creatinine concentration (UCr), urine volume (Uvol) of spot and 24-h urine samples were measured. Measured 24-h UIE was calculated from 24-h UIC multiplied by 24-h Uvol, while the estimated 24-h UIE was calculated from spot UI/Cr multiplied by 24-h urinary creatinine excretion (24-h UCrE). No significant difference was observed in 24-h Uvol between two repeated collections (P = 0·70), while spot UIC, 24-h UIC, spot UI/Cr and measured 24-h UIE were significantly different (P < 0·05). The estimated 24-h UIE was 247 (136-431) μg/day in the first collection, lower than the measured 24-h UIE of 329 (183-536) μg/day (P < 0·001), while no significant difference was observed (P = 0·30) in the second sampling as the estimated 24-h UIE was 355 (168-624) μg/day and the measured 24-h UIE 350 (181-615) μg/day. The spot UIC (r = 0·57, P < 0·001), spot UI/Cr (r = 0·63, P < 0·001) and the estimated 24-h UIE (r = 0·83, P < 0·001) were strongly correlated with the measured 24-h UIE in the first collection. Likewise, in the second sampling, spot UIC (r = 0·60, P < 0·001), spot UI/Cr (r = 0·72, P < 0·001) and the estimated 24-h UIE (r = 0·89, P < 0·001) were also correlated with measured 24-h UIE. The Bland-Altman results indicated 95% of subjects were expected to locate within the limits of agreement (LOA), but showed an underestimation of the urinary iodine excretion by the estimated 24-h UIE. In addition, moderate-to-good agreement was found for the estimated and measured 24-h UIE, with kappa values of 0·55 and 0·66. Estimated 24-h UIE by UI/Cr ratio from spot urine could represent a valid and reliable alternative for measured 24-h UIE in estimating iodine excretion in children. © 2016 John Wiley & Sons Ltd.

Metabolism of Nonessential N15-Labeled Amino Acids and the Measurement of Human Whole-Body Protein Synthesis Rates

NASA Technical Reports Server (NTRS)

Stein, T. P.; Settle, R. G.; Albina, J. A.; Dempsey, D. T.; Melnick, G.

1991-01-01

Eight N-15 labeled nonessential amino acids plus (15)NH4Cl were administered over a 10 h period to four healthy adult males using a primed-constant dosage regimen. The amount of N-15 excreted in the urine and the urinary ammonia, hippuric acid, and plasma alanine N-15 enrichments were measured. There was a high degree of consistency across subjects in the ordering of the nine compounds based on the fraction of N-15 excreted (Kendall coefficient of concordance W = 0.83, P is less than 0.01). Protein synthesis rates were calculated from the urinary ammonia plateau enrichment and the cumulative excretion of N-15. Glycine was one of the few amino acids that gave similar values by both methods.

Soy foods and urinary isoprostanes: results from a randomized study in premenopausal women.

PubMed

Sen, Cherisse; Morimoto, Yukiko; Heak, Sreang; Cooney, Robert V; Franke, Adrian A; Maskarinec, Gertraud

2012-05-01

In addition to their antiestrogenic effects, soy isoflavones may protect against cancer through alternate biological actions, for example, antioxidant properties. This randomized crossover study explored the relationship between dietary isoflavone intake through common soy foods and oxidative stress quantified by urinary isoprostane levels. Eighty-two women aged 39.2 ± 6.1 years were randomly selected to receive a high soy diet of 2 soy food servings per day and a low soy diet of <3 servings per week for 6 months each, separated by a 1-month washout period. Urine samples were collected at baseline and at the end of each dietary period. Urinary isoprostane levels were measured using enzyme-linked immunosorbent assays (ELISA) and adjusted for creatinine levels. Mixed models using log-transformed values were applied to evaluate the effect of the high soy diet. Unadjusted isoprostane excretion levels were lower during the high rather than the low soy diet, but this effect was not statistically significant (p = 0.81). After adjustment for urinary creatinine, isoprostane excretion was slightly higher during the high soy diet (p = 0.02), an observation that was confirmed in a regression analysis between urinary isoflavones and isoprostanes during the high soy diet. The original association remained significant when restricted to adherent participants, however this effect disappeared after exclusion of three extreme values. In agreement with several previous reports, these findings do not support the hypothesis that soy exerts antioxidant effects, as measured by urinary isoprostane excretions, but additional markers of oxidative stress need to be investigated in future studies.

Soy Foods and Urinary Isoprostanes: Results from a Randomized Study in Premenopausal Women

PubMed Central

Sen, Cherisse; Morimoto, Yukiko; Heak, Sreang; Cooney, Robert V.; Franke, Adrian A.; Maskarinec, Gertraud

2013-01-01

In addition to their antiestrogenic effects, soy isoflavones may protect against cancer through alternate biologic actions including antioxidant properties. This randomized, crossover study explored the relation between dietary isoflavone intake through common soy foods and oxidative stress quantified by urinary isoprostane levels. Eighty-two women aged 39.2±6.1 years were randomized to a high soy diet of 2 soy food servings per day and a low soy diet of <3 servings per week for 6 months each, separated by a 1 month washout period. Urine samples were collected at baseline and at the end of each dietary period. Urinary isoprostane levels were measured using enzyme-linked immunosorbent assays (ELISA) and adjusted for creatinine levels. Mixed models using log-transformed values were applied to evaluate the effect of the high soy diet. Unadjusted isoprostane excretion levels were lower during the high than the low soy diet, but this effect was not statistically significant (p=0.81). After adjustment for urinary creatinine, isoprostane excretion was slightly higher during the high soy diet (p=0.02), an observation that was confirmed in a regression analysis between urinary isoflavones and isoprostanes during the high soy diet. The original association remained significant when restricted to adherent participants; however, this effect disappeared after exclusion of three extreme values. In agreement with several previous reports, these findings do not support the hypothesis that soy exerts antioxidant effects as measured by urinary isoprostane excretions, but additional markers of oxidative stress need to be investigated in future studies. PMID:22331037

Relation of dietary salt and aldosterone to urinary protein excretion in subjects with resistant hypertension.

PubMed

Pimenta, Eduardo; Gaddam, Krishna K; Pratt-Ubunama, Monique N; Nishizaka, Mari K; Aban, Inmaculada; Oparil, Suzanne; Calhoun, David A

2008-02-01

Experimental data indicate that the cardiorenal effects of aldosterone excess are dependent on concomitant high dietary salt intake. Such an interaction of endogenous aldosterone and dietary salt has not been observed previously in humans. We assessed the hypothesis that excess aldosterone and high dietary sodium intake combine to worsen proteinuria in patients with resistant hypertension. Consecutive subjects with resistant hypertension (n=84) were prospectively evaluated by measurement of 24-hour urinary aldosterone (Ualdo), sodium, and protein (Uprot) excretion. Subjects were analyzed according to aldosterone status (high: Ualdo >or=12 microg/24 hours; or normal: <12 microg/24 hours) and dietary salt intake based on tertiles of urinary sodium. The mean clinic blood pressure for all of the subjects was 161.4+/-22.4/89.8+/-13.5 mm Hg on an average of 4.3 medications. There was no blood pressure difference between study groups. Uprot was significantly higher in the 38 subjects with high Ualdo compared with the 46 subjects with normal Ualdo (143.0+/-83.8 versus 95.9+/-81.7 mg/24 hours; P=0.01). Among subjects with high Ualdo, Uprot increased progressively across urinary sodium groups (P<0.05). In contrast, there was no difference in Uprot across sodium tertiles among subjects with normal Ualdo. A positive correlation between Uprot and urinary sodium (r=0.47; P=0.003) was observed in subjects with high Ualdo but not in subjects with normal Ualdo (r=0.18; P value not significant). These results suggest that aldosterone excess and high dietary salt combine to increase urinary protein excretion.

Additive effect of ketoconazole and octreotide in the treatment of severe adrenocorticotropin-dependent hypercortisolism.

PubMed

Vignati, F; Loli, P

1996-08-01

Over the last few years ketoconazole and octreotide have been employed in the treatment of pituitary-dependent or ectopic Cushing's syndrome. In four patients (two men and two women, aged 25-64 yr) with severe ACTH-dependent hypercortisolism in whom medical treatment with ketoconazole showed limited effectiveness and/or tolerability, we tried the association with octreotide. In all patients ketoconazole (200-1000 mg) induced a marked decrease in urinary free cortisol (UFC) excretion, but normalization could not be achieved. After ketoconazole discontinuation, three patients received octreotide alone (300-1500 micrograms/day, sc). This drug caused a dramatic decrease in UFC excretion, although not normalization; in all patients, escape from treatment occurred. Combined treatment was carried out for 10-180 days. Urinary cortisol excretion normalized and remained steadily within normal limits in three of four patients in whom normal UFC excretion had never been attained with both single drug regimens; in the fourth patient, UFC excretion decreased to levels lower than those achieved with ketoconazole or octreotide alone. The association with octreotide allowed a reduction in the daily dose of ketoconazole in three patients. Consistent with the steady reduction of cortisol production, a striking clinical improvement occurred in all patients after starting combined treatment. The normalization of UFC in three of four patients treated with both agents suggests that this approach may be useful in the long term treatment of severe forms of hypercortisolism of both pituitary and ectopic origin. In contrast to the limited effectiveness of each drug taken singularly at the same or higher doses, the association of the two drugs had an additive effect in the attainment of normal urinary cortisol excretion.

Chronic prazosin attenuates the natriuretic response to a modest saline load in anaesthetized rats.

PubMed Central

Penner, S. B.; Smyth, D. D.

1988-01-01

1. The effect of chronic prazosin pretreatment (3 days) on the ability to excrete a modest saline load (i.v. saline, 0.097 ml min-1) was studied in the anaesthetized rat. Three days before the experiment, the drinking water was replaced with 0.5% dextrose (control), 0.015 mg ml-1 prazosin in 0.5% dextrose (low dose) or 0.15 mg ml-1 prazosin in 0.5% dextrose (high dose). 2. The selectivity of the prazosin for alpha 1-adrenoceptors was evaluated in pithed rats. The pressor response to phenylephrine was partially attenuated by the low dose of prazosin and completely attenuated by the high dose of prazosin. The pressor response to clonidine was slightly decreased by the 3 day prazosin pretreatment indicating a selectivity for alpha 1-adrenoceptors. 3. In rats pretreated with the low dose of prazosin, there was a significant decrease in sodium and water, but not potassium excretion as compared to the control group. Captopril failed to alter these effects of the low dose of prazosin. Blood pressure and creatinine clearance were the same in both groups. In rats pretreated with the high dose of prazosin, there was a further decrease in sodium and water but not potassium excretion. However, this dose of prazosin also significantly decreased blood pressure and increased creatinine clearance. A decrease in renal perfusion pressure with an aortic clamp to the same level as that observed with the high prazosin dose also decreased sodium and water but not potassium excretion. The decrease in sodium and water excretion was not as great as that observed with the high dose of prazosin.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2896036

Signification of distal urinary acidification defects in hypocitraturic patients

PubMed Central

Forni Ogna, Valentina; Blanchard, Anne; Vargas-Poussou, Rosa; Ogna, Adam; Baron, Stéphanie; Bertocchio, Jean-Philippe; Prot-Bertoye, Caroline; Nevoux, Jérôme; Dubourg, Julie; Maruani, Gérard; Mendes, Margarida; Garcia-Castaño, Alejandro; Treard, Cyrielle; Lepottier, Nelly; Houillier, Pascal; Courbebaisse, Marie

2017-01-01

Background and objectives Hypocitraturia has been associated with metabolic acidosis and mineral disorders. The aim of this study was to investigate the occurrence of urinary acidification defects underlying hypocitraturia. Materials and methods This retrospective observational study included 67 patients (32 men), aged 40.7±15.1 years with hypocitraturia (<1.67 mmol/24-h) and nephrolithiasis, nephrocalcinosis, and/or bone demineralization, referred to our center from 2000 to 2015. We aimed to assess renal distal acidification capacity, prevalence and mechanisms of urinary acidification defects. Patients with low baseline plasma HCO3- (<22 mmol/L) were studied by bicarbonate loading or furosemide/fludrocortisone tests. Patients with normal baseline plasma HCO3- had an ammonium-chloride challenge test. A normal response was a decrease in urinary pH <5.3 and an increase in urinary NH4+ ≥33 μmol/min and defined idiopathic hypocitraturia. Results Eleven patients (16.4%) had low HCO3- and overt distal acidification defect. Three had a mutation in the gene encoding AE1, 4 had Gougerot-Sjögren syndrome and no cause was found in the remaining 4 cases. Fifty-six patients (83.6%) had normal HCO3-; of those, 33 (58.9%) had idiopathic hypocitraturia. Among the 23 (41%) remaining patients, 12 were unable to increase urinary NH4+ excretion (among them, 8 were able to decrease urinary pH and 4 were not) whereas 11 were able to increase urinary NH4+ excretion but unable to decrease urinary pH. These 11 patients had higher fasting urinary calcium, reflecting bone resorption, than the other 12 patients: median 0.41 [0.24–0.47] vs. 0.22 [0.08–0.37] mmol/mmol creatinine (P = 0.04). Conclusions Patients with hypocitraturia and normal plasma HCO3- frequently show a latent acidification defect that can be further dissected into one of several subtypes based on urinary pH and NH4+ response to the acid load. Those patients with impaired urine acidification capacity but preserved NH4+ excretion exhibit particularly high calciuria and should be identified to optimize nephrolithiasis prevention. PMID:28542241

Urinary proteomics in renal pathophysiology: Impact of proteinuria.

PubMed

Sancho-Martínez, Sandra M; Prieto-García, Laura; Blanco-Gozalo, Víctor; Fontecha-Barriuso, Miguel; López-Novoa, José M; López-Hernández, Francisco J

2015-06-01

Urinary differential proteomics is used to study renal pathophysiological mechanisms, find novel markers of biological processes and renal diseases, and stratify patients according to proteomic profiles. The proteomic procedure determines the pathophysiological meaning and clinical relevance of results. Urine samples for differential proteomic studies are usually normalized by protein content, regardless of its pathophysiological characteristics. In the field of nephrology, this approach translates into the comparison of a different fraction of the total daily urine output between proteinuric and nonproteinuric samples. Accordingly, alterations in the level of specific proteins found by this method reflect the relative presence of individual proteins in the urine; but they do not necessarily show alterations in their daily excretion, which is a key parameter for the understanding of the pathophysiological meaning of urinary components. For renal pathophysiology studies and clinical biomarker identification or determination, an alternative proteomic concept providing complementary information is based on sample normalization by daily urine output, which directly informs on changes in the daily excretion of individual proteins. This is clinically important because daily excretion (rather than absolute or relative concentration) is the only self-normalized way to evaluate the real meaning of urinary parameters, which is also independent of urine concentration. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The atypical excretion profile of meldonium: Comparison of urinary detection windows after single- and multiple-dose application in healthy volunteers.

PubMed

Görgens, Christian; Guddat, Sven; Bosse, Christina; Geyer, Hans; Pop, Valentin; Schänzer, Wilhelm; Thevis, Mario

2017-05-10

Following a one-year monitoring program providing unequivocal analytical evidence for a high prevalence in international elite sports, meldonium has been included in the World Anti-Doping Agency's (WADA) list of prohibited substances that came into effect on 1 January 2016. Despite of the polar and hydrophilic nature of the molecule, an unusual long detection window was observed in pilot elimination studies. Consequently, in the present study, urinary excretion profiles after single-dose (5 volunteers, 1×500mg) and multiple-dose oral application (5 volunteers; 2×500mg/day for 6days) were determined in order to facilitate the result management concerning meldonium findings in doping controls. Particularly the option to differentiate between recent use and tapering concentrations was studied. Urinary meldonium concentrations were determined using an analytical approach based on hydrophilic interaction liquid chromatography and high resolution tandem mass spectrometry. The study corroborates the hypothesis of a non-linear, dose-depended and biphasic excretion profile after oral application of meldonium and demonstrates that urinary detection windows are of considerable extent with up to 65 and 117days (concentrations>LOQ of 10ng/mL) following single- and multiple-dose applications, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.