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Sample records for renal tubular sodium

  1. Renal tubular NHE3 is required in the maintenance of water and sodium chloride homeostasis.

    Science.gov (United States)

    Fenton, Robert A; Poulsen, Søren B; de la Mora Chavez, Samantha; Soleimani, Manoocher; Dominguez Rieg, Jessica A; Rieg, Timo

    2017-08-01

    The sodium/proton exchanger isoform 3 (NHE3) is expressed in the intestine and the kidney, where it facilitates sodium (re)absorption and proton secretion. The importance of NHE3 in the kidney for sodium chloride homeostasis, relative to the intestine, is unknown. Constitutive tubule-specific NHE3 knockout mice (NHE3 loxloxCre) did not show significant differences compared to control mice in body weight, blood pH or bicarbonate and plasma sodium, potassium, or aldosterone levels. Fluid intake, urinary flow rate, urinary sodium/creatinine, and pH were significantly elevated in NHE3 loxloxCre mice, while urine osmolality and GFR were significantly lower. Water deprivation revealed a small urinary concentrating defect in NHE3 loxloxCre mice on a control diet, exaggerated on low sodium chloride. Ten days of low or high sodium chloride diet did not affect plasma sodium in control mice; however, NHE3 loxloxCre mice were susceptible to low sodium chloride (about -4 mM) or high sodium chloride intake (about +2 mM) versus baseline, effects without differences in plasma aldosterone between groups. Blood pressure was significantly lower in NHE3 loxloxCre mice and was sodium chloride sensitive. In control mice, the expression of the sodium/phosphate co-transporter Npt2c was sodium chloride sensitive. However, lack of tubular NHE3 blunted Npt2c expression. Alterations in the abundances of sodium/chloride cotransporter and its phosphorylation at threonine 58 as well as the abundances of the α-subunit of the epithelial sodium channel, and its cleaved form, were also apparent in NHE3 loxloxCre mice. Thus, renal NHE3 is required to maintain blood pressure and steady-state plasma sodium levels when dietary sodium chloride intake is modified. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  2. Distal renal tubular acidosis

    Science.gov (United States)

    ... this disorder. Alternative Names Renal tubular acidosis - distal; Renal tubular acidosis type I; Type I RTA; RTA - distal; Classical RTA Images Kidney anatomy Kidney - blood and urine flow References Bose A, Monk RD, Bushinsky DA. Kidney ...

  3. Effects of renal denervation on tubular sodium handling in rats with CBL-induced liver cirrhosis

    DEFF Research Database (Denmark)

    Jonassen, T.E.; Brond, L.; Torp, M.

    2003-01-01

    This study was designed to examine the effect of bilateral renal denervation (DNX) on thick ascending limb of Henle's loop (TAL) function in rats with liver cirrhosis induced by common bile duct ligation (CBL). The CBL rats had, as previously shown, sodium retention associated with hypertrophy...... renal sympathetic nerve activity known to be present in CBL rats plays a significant role in the formation of sodium retention by stimulating sodium reabsorption in the TAL via increased renal abundance of NKCC2....

  4. Effect of renal venous pressure elevation on tubular sodium and water reabsorption in the dog kidney

    DEFF Research Database (Denmark)

    Abildgaard, U; Amtorp, O; Holstein-Rathlou, N H

    1988-01-01

    of [51Cr]EDTA was used as a measure of the rate of glomerular filtration (GFR). GFR, urinary excretion rates of sodium and water, and lithium clearance were used for assessing the absolute and fractional reabsorption rates of sodium and water in the proximal as well as in more distal segments......This study was performed in order to quantify the effects of renal venous pressure (RVP) elevation on absolute and fractional reabsorption rates of sodium and water in proximal and distal segments of the nephron in dog kidneys. Renal blood flow (RBF) was measured electromagnetically. Clearance...

  5. Lithium clearance and renal tubular sodium handling during acute and long-term nifedipine treatment in essential hypertension

    DEFF Research Database (Denmark)

    Bruun, N E; Ibsen, H; Skøtt, P

    1988-01-01

    1. In two separate studies the lithium clearance method was used to evaluate the influence of acute and long-term nifedipine treatment on renal tubular sodium reabsorption. 2. In the acute study, after a 4 week placebo period two doses of 20 mg of nifedipine decreased supine blood pressure from 155...... were also unchanged, as were potassium clearance, urine flow and body weight. 3. In the long-term study, lithium clearance, glomerular filtration rate, sodium clearance, potassium clearance, urine flow and body fluid volumes were measured after a 4 weeks placebo period and after 6 and 12 weeks....../101 (20.6/13.5) +/- 11/4 (1.5/0.5) to 139/88 (18.5/11.7) +/- 16/9 (2.1/1.2) mmHg (kPa) (means +/- SD; P less than 0.01). Lithium clearance, glomerular filtration rate and sodium clearance did not change. Therefore the calculated values of absolute proximal and absolute distal sodium reabsorption rates...

  6. Atrial Natriuretic Peptide Stimulates Dopamine Tubular Transport by Organic Cation Transporters: A Novel Mechanism to Enhance Renal Sodium Excretion

    Science.gov (United States)

    Kouyoumdzian, Nicolás M.; Rukavina Mikusic, Natalia L.; Kravetz, María C.; Lee, Brenda M.; Carranza, Andrea; Del Mauro, Julieta S.; Pandolfo, Marcela; Gironacci, Mariela M.; Gorzalczany, Susana; Toblli, Jorge E.; Fernández, Belisario E.

    2016-01-01

    The aim of this study was to demonstrate the effects of atrial natriuretic peptide (ANP) on organic cation transporters (OCTs) expression and activity, and its consequences on dopamine urinary levels, Na+, K+-ATPase activity and renal function. Male Sprague Dawley rats were infused with isotonic saline solution during 120 minutes and randomized in nine different groups: control, pargyline plus tolcapone (P+T), ANP, dopamine (DA), D-22, DA+D-22, ANP+D-22, ANP+DA and ANP+DA+D-22. Renal functional parameters were determined and urinary dopamine concentration was quantified by HPLC. Expression of OCTs and D1-receptor in membrane preparations from renal cortex tissues were determined by western blot and Na+, K+-ATPase activity was determined using in vitro enzyme assay. 3H-DA renal uptake was determined in vitro. Compared to P+T group, ANP and dopamine infusion increased diuresis, urinary sodium and dopamine excretion significantly. These effects were more pronounced in ANP+DA group and reversed by OCTs blockade by D-22, demonstrating that OCTs are implied in ANP stimulated-DA uptake and transport in renal tissues. The activity of Na+, K+-ATPase exhibited a similar fashion when it was measured in the same experimental groups. Although OCTs and D1-receptor protein expression were not modified by ANP, OCTs-dependent-dopamine tubular uptake was increased by ANP through activation of NPR-A receptor and protein kinase G as signaling pathway. This effect was reflected by an increase in urinary dopamine excretion, natriuresis, diuresis and decreased Na+, K+-ATPase activity. OCTs represent a novel target that links the activity of ANP and dopamine together in a common mechanism to enhance their natriuretic and diuretic effects. PMID:27392042

  7. Effects of dopamine on renal haemodynamics tubular function and sodium excretion in normal humans

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal

    1998-01-01

    The renal functional changes following infusion of dopamine are well documented. The most pronounced effect is the increase in renal blood flow and a marked natriuretic response. Due to its specific renal effects, dopamine has become one of the most frequently used drugs in the treatment...... of critically ill patients with low cardiac output states and/or acute oliguric renal failure. Pharmacological effects of dopamine are dose dependent. Low doses of dopamine predominantly stimulate dopaminergic receptors, but with increasing doses actions secondary to stimulation of adrenergic beta(1) and alpha...... indirectly may dilate the vessels by inhibition of norepinephrine release. Consistent with previous results in animals, the present haemodynamic studies revealed that dopamine in normal subjects elicits a dose dependent biphasic effect on the mean arterial blood pressure. With 1 and 2 micrograms...

  8. Effect of metabolic acidosis on renal tubular sodium handling in rats as determined by lithium clearance

    Directory of Open Access Journals (Sweden)

    Menegon L.F.

    1998-01-01

    Full Text Available Systemic metabolic acidosis is known to cause a decrease in salt and water reabsorption by the kidney. We have used renal lithium clearance to investigate the effect of chronic, NH4Cl-induced metabolic acidosis on the renal handling of Na+ in male Wistar-Hannover rats (200-250 g. Chronic acidosis (pH 7.16 ± 0.13 caused a sustained increase in renal fractional Na+ excretion (267.9 ± 36.4%, accompanied by an increase in fractional proximal (113.3 ± 3.6% and post-proximal (179.7 ± 20.2% Na+ and urinary K+ (163.4 ± 5.6% excretion when compared to control and pair-fed rats. These differences occurred in spite of an unchanged creatinine clearance and Na+ filtered load. A lower final body weight was observed in the acidotic (232 ± 4.6 g and pair-fed (225 ± 3.6 g rats compared to the controls (258 ± 3.7 g. In contrast, there was a significant increase in the kidney weights of acidotic rats (1.73 ± 0.05 g compared to the other experimental groups (control, 1.46 ± 0.05 g; pair-fed, 1.4 ± 0.05 g. We suggest that altered renal Na+ and K+ handling in acidotic rats may result from a reciprocal relationship between the level of metabolism in renal tubules and ion transport.

  9. Reactive Oxygen Species Modulation of Na/K-ATPase Regulates Fibrosis and Renal Proximal Tubular Sodium Handling

    Directory of Open Access Journals (Sweden)

    Jiang Liu

    2012-01-01

    Full Text Available The Na/K-ATPase is the primary force regulating renal sodium handling and plays a key role in both ion homeostasis and blood pressure regulation. Recently, cardiotonic steroids (CTS-mediated Na/K-ATPase signaling has been shown to regulate fibrosis, renal proximal tubule (RPT sodium reabsorption, and experimental Dahl salt-sensitive hypertension in response to a high-salt diet. Reactive oxygen species (ROS are an important modulator of nephron ion transport. As there is limited knowledge regarding the role of ROS-mediated fibrosis and RPT sodium reabsorption through the Na/K-ATPase, the focus of this review is to examine the possible role of ROS in the regulation of Na/K-ATPase activity, its signaling, fibrosis, and RPT sodium reabsorption.

  10. Renal tubular reabsorption of sodium and water during infusion of low-dose dopamine in normal man

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Hansen, J M; Ladefoged, S D

    1990-01-01

    of sodium and water during dopamine infusion (3 micrograms min-1 kg-1) were estimated in 12 normal volunteers. 2. CNa increased by 128% (P less than 0.001). Effective renal plasma flow and GFR increased by 43% (P less than 0.001) and 9% (P less than 0.01), respectively. CLi increased in all subjects by......, on average, 44% (P less than 0.001). Fractional proximal reabsorption [1-(CLi/GFR)] decreased by 13% after dopamine infusion (P less than 0.001), and estimated absolute proximal reabsorption rate (GFR-CLi) decreased by 8% (P less than 0.01). Absolute distal sodium reabsorption rate [(CLi-CNa) x PNa, where...... PNa is plasma sodium concentration] increased (P less than 0.001), and fractional distal sodium reabsorption [(CLi-CNa)/CLi] decreased (P less than 0.001). 3. It is concluded that natriuresis during low-dose dopamine infusion is caused by an increased outflow of sodium from the proximal tubules...

  11. Effects of intravenous bumetanide administration on renal haemodynamics and proximal and distal tubular sodium reabsorption in conscious rats

    Energy Technology Data Exchange (ETDEWEB)

    Shalmi, M.; Petersen, J.S.; Christensen, S. (Department of pharmacology, University of Copenhagen (Denmark))

    1989-01-01

    The renal effects of 0.02-62.5 mg/kg bumetanide given as intravenous bolus injections were studied in water diuretic conscious rats. Clearances of {sup 14}C-tetraethylammonium, {sup 3}H-inulin and lithium were used as markers for renal plasma flow (RPF), glomerular filtion rate (GFR) and proximal tubular output, respectively. Bumetanide caused biphasic, transient and dose-independent changes in the renal haemodynamics without significant alterations of the filtration fraction. At dose-levels above 0.02 mg/kg bumetanide increased urine flow, absolute and fractional Na excretion as well as the indices for fractional output of Na from the proximal tubules (C{sub Li}/C{sub I}n) and the distal nephron segments (C{sub Na}/C{sub Li}). The changes in C{sub Li}/C{sub In} became maximal at doses above 0.5 mg/kg, whereas C{sub Na}/C{sub Li} was increased with the dose up to 12.5 mg/kg. Paradoxically, doses above 12.5 mg/kg were less natriuretic due to a decrease of C{sub Na}/C{sub Li}. It is concluded that in rats bumetanide is an effective although short-acting diuretic when administered intravenously. When comparing peak responses bumetanide is equipotent to furosemide but has a lower maximal efficacy. Judged from the changes in fractional lithium excretion, the natriuretic effect of bumetanide is effected by inhibition of Na reabsorption in the proximal tubule in addition to the well-known effect on the distal nephron segment. (author).

  12. Sodium glucose co-transporter 2 inhibitors: blocking renal tubular reabsorption of glucose to improve glycaemic control in patients with diabetes.

    Science.gov (United States)

    Jabbour, S A; Goldstein, B J

    2008-08-01

    The kidney plays a central role in the regulation of plasma glucose levels, although until recently this has not been widely appreciated or considered a target for therapeutic intervention. The sodium glucose co-transporter type 2 (SGLT2) located in the plasma membrane of cells lining the proximal tubule mediates the majority of renal glucose reabsorption from the tubular fluid, which normally prevents the loss of glucose in the urine. Competitive inhibitors of SGLT2 that provoke the renal excretion of glucose have been discovered, thereby providing a unique mechanism to potentially lower the elevated blood glucose levels in patients with diabetes. To explore the physiology of SGLT2 action and discuss several SGLT2 inhibitors that have entered early clinical development. All publicly available data were identified by searching the internet for 'SGLT2' and 'SGLT2 inhibitor' through 1 November 2007. Published articles, press releases and abstracts presented at national and international meetings were considered. Sodium glucose co-transporter type 2 inhibition is a novel treatment option for diabetes, which has been studied in preclinical models and a few potent and selective SGLT2 inhibitors have been reported and are currently in clinical development. These agents appear to be safe and generally well tolerated, and will potentially be a beneficial addition to the growing battery of oral antihyperglycaemic agents.

  13. Renal Tubular Function in Systemic Lupus Erythematosus*

    African Journals Online (AJOL)

    immune' diseases such as. Sjogren's syndrome,'" systemic lupus erythematosus. (SLE),3 alveolitis' and chronic active hepatitis.' The reported abnormalities of renal tubular function include impairment of acid excretion and urinary concentration.

  14. A neglected case of Renal Tubular Acidosis

    International Nuclear Information System (INIS)

    Derakhshan, A.; Basiratnia, M.; Fallahzadeh, M.H.; Al-Hashemi, G.H.

    2007-01-01

    In this report, we present a case of a child with distal renal tubular acidosis, severe failure to thrive and profound rickets, who was only 7.8 Kg when presented at 6 years of age. His response to treatment and his follow up for four years is discussed. Although failure to thrive is a common finding in renal tubular acidosis but the physical and x-ray findings in our case were unique. (author)

  15. Electrolyte composition of renal tubular cells in gentamicin nephrotoxicity

    International Nuclear Information System (INIS)

    Matsuda, O.; Beck, F.X.; Doerge, A.T.; Thurau, K.

    1988-01-01

    The effect of long-term gentamicin administration on sodium, potassium, chloride and phosphorus concentrations was studied in individual rat renal tubular cells using electron microprobe analysis. Histological damage was apparent only in proximal tubular cells. The extent of damage was only mild after 7 days of gentamicin administration (60 mg/kg body wt/day) but much more pronounced after 10 days. GFR showed a progressive decline during gentamicin treatment. In non-necrotic proximal tubular cells, sodium was increased from 14.6 +/- 0.3 (mean +/- SEM) in controls to 20.6 +/- 0.4 after 7 and 22.0 +/- 0.8 mmol/kg wet wt after 10 days of gentamicin administration. Chloride concentration was higher only after 10 days (20.6 +/- 0.6 vs. 17.3 +/- 0.2 mmol/kg wet wt). Both cell potassium and phosphorus concentrations were diminished by 6 and 15, and by 8 and 25 mmol/kg wet wt after 7 and 10 days of treatment, respectively. In contrast, no major alterations in distal tubular cell electrolyte concentrations could be observed after either 7 or 10 days of gentamicin administration. As in proximal tubular cells, distal tubular cell phosphorus concentrations were, however, lowered by gentamicin treatment. These results clearly indicate that gentamicin exerts its main effect on proximal tubular cells. Decreased potassium and increased sodium and chloride concentrations were observed in proximal tubular cells exhibiting only mild histological damage prior to the onset of advanced tissue injury. Necrotic cells, on the other hand, showed widely variable intracellular electrolyte concentration patterns

  16. Distal renal tubular acidosis in recurrent renal stone formers

    DEFF Research Database (Denmark)

    Osther, P J; Hansen, A B; Røhl, H F

    1989-01-01

    Renal acidification ability was examined in 90 recurrent renal stone formers, using fasting morning urinary pH levels followed by a short ammonium chloride loading test in subjects with pH levels above 6.0. Fifteen patients (16.6%) revealed a distal renal tubular acidification defect: one patient......, this has important therapeutic implications. The pathological sequence in renal stone formers with dRTA is discussed....

  17. Screening renal stone formers for distal renal tubular acidosis

    DEFF Research Database (Denmark)

    Osther, P J; Hansen, A B; Røhl, H F

    1989-01-01

    A group of 110 consecutive renal stone formers were screened for distal renal tubular acidosis (RTA) using morning fasting urinary pH (mfUpH) levels followed by a short ammonium chloride loading test in patients with levels above 6.0. In 14 patients (12.7%) a renal acidification defect was noted...... RTA in renal stone formers. Regardless of whether the acidification defect is primary or secondary to stone formation, however, all renal stone formers with distal RTA can expect to benefit from prophylactic alkaline therapy and it is recommended that the screening procedure, which is easy to use...

  18. Cyclosporine A induces senescence in renal tubular epithelial cells

    NARCIS (Netherlands)

    Jennings, Paul; Koppelstaetter, Christian; Aydin, Sonia; Abberger, Thomas; Wolf, Anna Maria; Mayer, Gert; Pfaller, Walter

    The nephrotoxic potential of the widely used immunosuppressive agent cyclosporine A (CsA) is well recognized. However, the mechanism of renal tubular toxicity is not yet fully elucidated. Chronic CsA nephropathy and renal organ aging share some clinical features, such as renal fibrosis and tubular

  19. Distal renal tubular acidosis and hepatic lipidosis in a cat.

    Science.gov (United States)

    Brown, S A; Spyridakis, L K; Crowell, W A

    1986-11-15

    Clinical and laboratory evidence of hepatic failure was found in a chronically anorectic cat. Simultaneous blood and urine pH determinations established a diagnosis of distal renal tubular acidosis. The cat did not respond to treatment. Necropsy revealed distal tubular nephrosis and hepatic lipidosis. The finding of distal renal tubular acidosis in a cat with hepatic lipidosis emphasizes the importance of complete evaluation of acid-base disorders in patients.

  20. Overall renal and tubular function during infusion of amino acids in normal man

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Hansen, J M; Ladefoged, S D

    1990-01-01

    sodium concentration] increased by 40% (P less than 0.001). Plasma renin concentration did not change significantly. 4. The results suggest that amino acids increase GFR by a primary effect on renal haemodynamics or, less likely, by reducing the signal to the tubuloglomerular feedback mechanism......1. Amino acids have been used to test renal reserve filtration capacity. Previous studies suggest that amino acids increase glomerular filtration rate (GFR) by reducing distal tubular flow and tubuloglomerular feedback activity. 2. Glomerular function and the renal tubular handling of sodium during...... infusion of amino acids was studied in 12 normal volunteers. 3. Clearance of sodium (CNa) was unchanged. Effective renal plasma flow increased slightly, but significantly, by 9% (P less than 0.05). GFR was increased by 13% (P less than 0.001). Clearance of lithium (CLi) (used as an index of proximal...

  1. Inherited renal tubular defects with hypokalemia

    Directory of Open Access Journals (Sweden)

    Muthukrishnan J

    2009-01-01

    Full Text Available Bartter′s and Gitelman′s syndrome are two ends of a spectrum of inherited renal tubular disorders that present with hypokalemic metabolic alkalosis of varying severity. Clinical features and associated calcium and magnesium ion abnormalities are used to diagnose these cases after excluding other commoner causes. We report on two cases, the first being a young boy, born of pregnancy complicated by polyhydramnios, who had classical dysmorphic features, polyuria, hypokalemia and hypercalciuria and was diagnosed as having Bartter′s syndrome. The second patient is a lady who had recurrent tetany as the only manifestation of Gitelman′s syndrome, which is an unusual presentation. Potassium replacement with supplementation of other deficient ions led to satisfactory clinical and biochemical response.

  2. Intrarenal purinergic signaling in the control of renal tubular transport

    DEFF Research Database (Denmark)

    Prætorius, Helle; Leipziger, Jens Georg

    2010-01-01

    Renal tubular epithelial cells receive hormonal input that regulates volume and electrolyte homeostasis. In addition, numerous intrarenal, local signaling agonists have appeared on the stage of renal physiology. One such system is that of intrarenal purinergic signaling. This system involves all......-reaching advances indicate that ATP is often used as a local transmitter for classical sensory transduction. This transmission apparently also applies to sensory functions in the kidney. Locally released ATP is involved in sensing of renal tubular flow or in detecting the distal tubular load of NaCl at the macula...

  3. Roles of Akt and SGK1 in the Regulation of Renal Tubular Transport

    Directory of Open Access Journals (Sweden)

    Nobuhiko Satoh

    2015-01-01

    Full Text Available A serine/threonine kinase Akt is a key mediator in various signaling pathways including regulation of renal tubular transport. In proximal tubules, Akt mediates insulin signaling via insulin receptor substrate 2 (IRS2 and stimulates sodium-bicarbonate cotransporter (NBCe1, resulting in increased sodium reabsorption. In insulin resistance, the IRS2 in kidney cortex is exceptionally preserved and may mediate the stimulatory effect of insulin on NBCe1 to cause hypertension in diabetes via sodium retention. Likewise, in distal convoluted tubules and cortical collecting ducts, insulin-induced Akt phosphorylation mediates several hormonal signals to enhance sodium-chloride cotransporter (NCC and epithelial sodium channel (ENaC activities, resulting in increased sodium reabsorption. Serum- and glucocorticoid-inducible kinase 1 (SGK1 mediates aldosterone signaling. Insulin can stimulate SGK1 to exert various effects on renal transporters. In renal cortical collecting ducts, SGK1 regulates the expression level of ENaC through inhibition of its degradation. In addition, SGK1 and Akt cooperatively regulate potassium secretion by renal outer medullary potassium channel (ROMK. Moreover, sodium-proton exchanger 3 (NHE3 in proximal tubules is possibly activated by SGK1. This review focuses on recent advances in understanding of the roles of Akt and SGK1 in the regulation of renal tubular transport.

  4. Intrarenal purinergic signaling in the control of renal tubular transport

    DEFF Research Database (Denmark)

    Prætorius, Helle; Leipziger, Jens Georg

    2010-01-01

    -reaching advances indicate that ATP is often used as a local transmitter for classical sensory transduction. This transmission apparently also applies to sensory functions in the kidney. Locally released ATP is involved in sensing of renal tubular flow or in detecting the distal tubular load of NaCl at the macula...

  5. Genetics Home Reference: renal tubular acidosis with deafness

    Science.gov (United States)

    ... adults with renal tubular acidosis with deafness have short stature, and many develop kidney stones. The metabolic acidosis ... enlarged vestibular aqueduct, can be seen with medical imaging. The vestibular aqueduct is a bony canal that ...

  6. Luminal nucleotides are tonic inhibitors of renal tubular transport

    DEFF Research Database (Denmark)

    Leipziger, Jens Georg

    2011-01-01

    PURPOSE OF REVIEW: Extracellular ATP is an essential local signaling molecule in all organ systems. In the kidney, purinergic signaling is involved in an array of functions and this review highlights those of relevance for renal tubular transport. RECENT FINDINGS: Purinergic receptors are express...... discovered as an important signaling compartment in which local purinergic signaling determines an inhibitory tone for renal tubular transport. Blocking components of this system leads to tubular hyper-absorption, volume retention and elevated blood pressure.......PURPOSE OF REVIEW: Extracellular ATP is an essential local signaling molecule in all organ systems. In the kidney, purinergic signaling is involved in an array of functions and this review highlights those of relevance for renal tubular transport. RECENT FINDINGS: Purinergic receptors are expressed...... in all renal tubular segments and their stimulation generally leads to transport inhibition. Recent evidence has identified the tubular lumen as a restricted space for purinergic signaling. The concentrations of ATP in the luminal fluids are sufficiently high to inflict a tonic inhibition of renal...

  7. Renal pathophysiologic role of cortical tubular inclusion bodies.

    Science.gov (United States)

    Radi, Zaher A; Stewart, Zachary S; Grzemski, Felicity A; Bobrowski, Walter F

    2013-01-01

    Renal tubular inclusion bodies are rarely associated with drug administration. The authors describe the finding of renal cortical tubular intranuclear and intracytoplasmic inclusion bodies associated with the oral administration of a norepinephrine/serotonin reuptake inhibitor (NSRI) test article in Sprague-Dawley (SD) rats. Rats were given an NSRI daily for 4 weeks, and kidney histopathologic, ultrastructural pathology, and immunohistochemical examinations were performed. Round eosinophilic intranuclear inclusion bodies were observed histologically in the tubular epithelial cells of the renal cortex in male and female SD rats given the NSRI compound. No evidence of degeneration or necrosis was noted in the inclusion-containing renal cells. By ultrastructural pathology, inclusion bodies consisted of finely granular, amorphous, and uniformly stained nonmembrane-bound material. By immunohistochemistry, inclusion bodies stained positive for d-amino acid oxidase (DAO) protein. In addition, similar inclusion bodies were noted in the cytoplasmic tubular epithelial compartment by ultrastructural and immunohistochemical examination.  This is the first description of these renal inclusion bodies after an NSRI test article administration in SD rats. Such drug-induced renal inclusion bodies are rat-specific, do not represent an expression of nephrotoxicity, represent altered metabolism of d-amino acids, and are not relevant to human safety risk assessment.

  8. 99mTc renal tubular function agents: Current status

    International Nuclear Information System (INIS)

    Eshima, D.; Fritzberg, A.R.; Taylor, A. Jr.

    1990-01-01

    Orthoiodohippuric (OIH) acid labeled with 131I is a widely used renal radiopharmaceutical agent and has been the standard radiopharmaceutical agent for the measurement of effective renal plasma flow (EPRF). Limitations to the routine clinical use of 131I OIH are related to the suboptimal imaging properties of the 131I radionuclide and its relatively high radiation dose. 123I has been substituted for 131I; however, its high cost and short shelf-life have limited its widespread use. Recent work has centered on the development of a new 99mTc renal tubular function agent, which would use the optimal radionuclidic properties and availability of 99mTc and combine the clinical information provided by OIH. The search for a suitable 99mTc renal tubular function agent has focused on the diamide dithiolate (N2S2), the paraaminohippuric iminodiacetic acid (PAHIDA), and the triamide mercaptide (N3S) donor ligand systems. To date, the most promising 99mTc tubular function agent is the N3S complex: 99mTc mercaptoacetyltriglycine (99mTc MAG3). Studies in animal models in diuresis, dehydration, acid or base imbalance, ischemia, and renal artery stenosis demonstrate that 99mTc MAG3 behaves similarly to 131I OIH. A simple kit formulation is available that yields the 99mTc MAG3 complex in high radiochemical purity. Studies in normal subjects and patients indicate that 99mTc MAG3 is an excellent 99mTc renal tubular agent, but its plasma clearance is only 50% to 60% that of OIH. In an effort to develop an improved 99mTc renal tubular function agent, changes have been made in the core N3S donor ligand system, but to date no agent has been synthesized that is clinically superior to 99mTc MAG3. 61 references

  9. Tubular overexpression of gremlin induces renal damage susceptibility in mice.

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    Alejandra Droguett

    Full Text Available A growing number of patients are recognized worldwide to have chronic kidney disease. Glomerular and interstitial fibrosis are hallmarks of renal progression. However, fibrosis of the kidney remains an unresolved challenge, and its molecular mechanisms are still not fully understood. Gremlin is an embryogenic gene that has been shown to play a key role in nephrogenesis, and its expression is generally low in the normal adult kidney. However, gremlin expression is elevated in many human renal diseases, including diabetic nephropathy, pauci-immune glomerulonephritis and chronic allograft nephropathy. Several studies have proposed that gremlin may be involved in renal damage by acting as a downstream mediator of TGF-β. To examine the in vivo role of gremlin in kidney pathophysiology, we generated seven viable transgenic mouse lines expressing human gremlin (GREM1 specifically in renal proximal tubular epithelial cells under the control of an androgen-regulated promoter. These lines demonstrated 1.2- to 200-fold increased GREM1 expression. GREM1 transgenic mice presented a normal phenotype and were without proteinuria and renal function involvement. In response to the acute renal damage cause by folic acid nephrotoxicity, tubule-specific GREM1 transgenic mice developed increased proteinuria after 7 and 14 days compared with wild-type treated mice. At 14 days tubular lesions, such as dilatation, epithelium flattening and hyaline casts, with interstitial cell infiltration and mild fibrosis were significantly more prominent in transgenic mice than wild-type mice. Tubular GREM1 overexpression was correlated with the renal upregulation of profibrotic factors, such as TGF-β and αSMA, and with increased numbers of monocytes/macrophages and lymphocytes compared to wild-type mice. Taken together, our results suggest that GREM1-overexpressing mice have an increased susceptibility to renal damage, supporting the involvement of gremlin in renal damage

  10. The rebirth of interest in renal tubular function.

    Science.gov (United States)

    Lowenstein, Jerome; Grantham, Jared J

    2016-06-01

    The measurement of glomerular filtration rate by the clearance of inulin or creatinine has evolved over the past 50 years into an estimated value based solely on plasma creatinine concentration. We have examined some of the misconceptions and misunderstandings of the classification of renal disease and its course, which have followed this evolution. Furthermore, renal plasma flow and tubular function, which in the past were estimated by the clearance of the exogenous aryl amine, para-aminohippurate, are no longer measured. Over the past decade, studies in experimental animals with reduced nephron mass and in patients with reduced renal function have identified small gut-derived, protein-bound uremic retention solutes ("uremic toxins") that are poorly filtered but are secreted into the lumen by organic anion transporters (OATs) in the proximal renal tubule. These are not effectively removed by conventional hemodialysis or peritoneal dialysis. Residual renal function, urine produced in patients with advanced renal failure or undergoing dialysis treatment, may represent, at least in part, secretion of fluid and uremic toxins, such as indoxyl sulfate, mediated by proximal tubule OATs and might serve as a useful survival function. In light of this new evidence of the physiological role of proximal tubule OATs, we suggest that measurement of renal tubular function and renal plasma flow may be of considerable value in understanding and managing chronic kidney disease. Data obtained in normal subjects indicate that renal plasma flow and renal tubular function might be measured by the clearance of the endogenous aryl amine, hippurate. Copyright © 2016 the American Physiological Society.

  11. Importance of early audiologic assessment in distal renal tubular acidosis

    Directory of Open Access Journals (Sweden)

    Elizabeth Norgett

    2010-12-01

    Full Text Available Anand P Swayamprakasam1, Elizabeth Stover1, Elizabeth Norgett1, Katherine G Blake-Palmer1, Michael J Cunningham2, Fiona E Karet11Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, UK; 2Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA, USAAbstract: Autosomal recessive distal renal tubular acidosis is usually a severe disease of childhood, often presenting as failure to thrive in infancy. It is often, but not always, accompanied by sensorineural hearing loss, the clinical severity and age of onset of which may be different from the other clinical features. Mutations in either ATP6V1B1 or ATP6V0A4 are the chief causes of primary distal renal tubular acidosis with or without hearing loss, although the loss is often milder in the latter. We describe a kindred with compound heterozygous alterations in ATP6V0A4, where hearing loss was formally diagnosed late in both siblings such that they missed early opportunities for hearing support. This kindred highlights the importance of routine audiologic assessments of all children with distal renal tubular acidosis, irrespective either of age at diagnosis or of which gene is mutated. In addition, when diagnostic genetic testing is undertaken, both genes should be screened irrespective of current hearing status. A strategy for this is outlined.Keywords: sensorineural hearing loss, renal tubular acidosis, recessive, genetics, mutation

  12. Recent advances in renal tubular calcium reabsorption.

    NARCIS (Netherlands)

    Mensenkamp, A.R.; Hoenderop, J.G.J.; Bindels, R.J.M.

    2006-01-01

    PURPOSE OF REVIEW: Knowledge of renal Ca2+ reabsorption has evolved greatly in recent years. This review focuses on two recent discoveries concerning passive and active Ca2+ reabsorption. RECENT FINDINGS: The thiazide diuretics are known for their hypocalciuric effect. Recently, it has been

  13. Angiotensin II and Renal Tubular Ion Transport

    Directory of Open Access Journals (Sweden)

    Patricia Valles

    2005-01-01

    Evidence for the regulation of H+-ATPase activity in vivo and in vitro by trafficking/exocytosis has been provided. An additional level of H+-ATPase regulation via protein synthesis may be important as well. Recently, we have shown that both aldosterone and angiotensin II provide such a mechanism of regulation in vivo at the level of the medullary collecting tubule. Interestingly, in this part of the nephron, the effects of aldosterone and angiotensin II are not sodium dependent, whereas in the cortical collecting duct, both aldosterone and angiotensin II, by contrast, affect H+ secretion by sodium-dependent mechanisms.

  14. The effects of cimetidine on creatinine excretion, glomerular filtration rate and tubular function in renal transplant recipients

    DEFF Research Database (Denmark)

    Olsen, N V; Ladefoged, S D; Feldt-Rasmussen, B

    1989-01-01

    The renal clearance of endogenous creatinine (CCr), sodium (CNa) and lithium (CLi) was determined before and after a single intravenous bolus of cimetidine in nine renal transplant recipients. The glomerular filtration rate (GFR) was measured with 125I-iothalamate clearance (CTh). The initial CCr...... tubular flow. This suggests that on-going cimetidine treatment must be taken into account when graft function is evaluated by the CCr alone....

  15. Mathematical rationalization for the renal tubular transport: revised concepts.

    Science.gov (United States)

    Mioni, Roberto; Marega, Alessandra; Romano, Giulio; Montanaro, Domenico

    2017-09-01

    The current emphasis on kinetics and in situ control of molecular exchanges, across the tubular membrane, has not been paralleled by corresponding improvements in our understanding of tubular behaviour at the macroscopic level of classical physiology. In this paper, we propose a mathematical rationalization of macroscopic tubular transport by means of a principal transport equation, originating from the law of mass action between substrate and carrier. The other equations, derived from the main one, demonstrate the possibility of distinguishing between transporters with low affinity and high capacity and transporters with high affinity and low capacity. Moreover, our model formalizes both tubular reabsorption and tubular secretion. Regarding the renal calcium handling, our model confirms the two-compartment system proposed by Mioni in 1971, with some important variants, which are in agreement with the fractional reabsorptions of this cation along the tubule, as verified by micro-puncture technique. To obtain the frequency distribution of saturated tubules, we have utilized the infinitesimal analysis method, starting from the equations proposed by Smith in 1943, concluding that all titration curves result from the combined effect of enzymatic approach and anatomical heterogeneity of the nephrons. The theoretical equations included in our manuscript reflect substantial and palpable physiological mechanisms able to suggest diagnosis and therapy of some electrolyte and hormonal disorders. At the end of this paper, we highlight advantages and disadvantages detectable by comparing our mathematical approach with Marshall's and Bijvoet's methods, proposed, respectively, in 1976 and 1984.

  16. Renal tubular acidosis complicated with hyponatremia due to cortisol insufficiency

    OpenAIRE

    Izumi, Yuichiro; Nakayama, Yushi; Onoue, Tomoaki; Inoue, Hideki; Mukoyama, Masashi

    2015-01-01

    Adrenocortical insufficiency such as occurs in Addison's disease causes hyponatremia and renal tubular acidosis (RTA). Hyponatremia results from both aldosterone and cortisol insufficiency. RTA is due to aldosterone insufficiency. The involvement of cortisol in RTA is unclear. Here, we report a woman in her 70s who was admitted to our hospital with severe hyponatremia (106 mEq/l) and RTA. The patient exhibited low plasma cortisol levels with little response to rapid adrenocorticotropic hormon...

  17. CD47 regulates renal tubular epithelial cell self-renewal and proliferation following renal ischemia reperfusion.

    Science.gov (United States)

    Rogers, Natasha M; Zhang, Zheng J; Wang, Jiao-Jing; Thomson, Angus W; Isenberg, Jeffrey S

    2016-08-01

    Defects in renal tubular epithelial cell repair contribute to renal ischemia reperfusion injury, cause acute kidney damage, and promote chronic renal disease. The matricellular protein thrombospondin-1 and its receptor CD47 are involved in experimental renal ischemia reperfusion injury, although the role of this interaction in renal recovery is unknown. We found upregulation of self-renewal genes (transcription factors Oct4, Sox2, Klf4 and cMyc) in the kidney of CD47(-/-) mice after ischemia reperfusion injury. Wild-type animals had minimal self-renewal gene expression, both before and after injury. Suggestive of cell autonomy, CD47(-/-) renal tubular epithelial cells were found to increase expression of the self-renewal genes. This correlated with enhanced proliferative capacity compared with cells from wild-type mice. Exogenous thrombospondin-1 inhibited self-renewal gene expression in renal tubular epithelial cells from wild-type but not CD47(-/-) mice, and this was associated with decreased proliferation. Treatment of renal tubular epithelial cells with a CD47 blocking antibody or CD47-targeting small interfering RNA increased expression of some self-renewal transcription factors and promoted cell proliferation. In a syngeneic kidney transplant model, treatment with a CD47 blocking antibody increased self-renewal transcription factor expression, decreased tissue damage, and improved renal function compared with that in control mice. Thus, thrombospondin-1 via CD47 inhibits renal tubular epithelial cell recovery after ischemia reperfusion injury through inhibition of proliferation/self-renewal. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  18. Renal transplantant blood flow in patients with acute tubular necrosis

    Energy Technology Data Exchange (ETDEWEB)

    Huic, D; Crnkovic, S; Bubic-Filipi, L J; Grosev, D; Dodig, P; Porapat, M; Puretic, Z [Univ. Hospital Rebro, Zagreb (Croatia)

    1997-09-01

    The aim of this study was to investigate the quantity of renal transport blood flow in patients affected by acute tubular necrosis (ATN). During the four years period two hundred and thirty-three studies were performed using {sup 99m}Tc pertechnetate and {sup 131}I - OIH. Renal blood flow was calculated from the first-pass time activity curves generated over the kidney and aorta and expressed as a percentage of cardiac output (RBF/CO). Renal transplant blood flow is clearly diminished in ATN, similar as in acute rejection, and significantly related to the graft function, what means that RBF/CO value could potentially serve as a prognostic factor in the graft function recovery from ATN.

  19. Distal renal tubular acidosis and amelogenesis imperfecta: A rare association

    Directory of Open Access Journals (Sweden)

    P Ravi

    2013-01-01

    Full Text Available Renal tubular acidosis (RTA is characterized by a normal anion gap with hyperchloremic metabolic acidosis. Primary distal RTA (type I is the most common RTA in children. Childhood presentation of distal RTA includes vomiting, failure to thrive, metabolic acidosis, and hypokalemia. Amelogenesis imperfecta (AI represents a condition where the dental enamel and oral tissues are affected in an equal manner resulting in the hypoplastic or hypopigmented teeth. We report a 10-year-old girl, previously asymptomatic presented with the hypokalemic paralysis and on work-up found out to have type I RTA. The discoloration of teeth and enamel was diagnosed as AI.

  20. Amelogenesis Imperfecta with Distal Renal Tubular Acidosis: A Novel Syndrome?

    Science.gov (United States)

    Misgar, R A; Hassan, Z; Wani, A I; Bashir, M I

    2017-01-01

    Amelogenesis imperfecta (AI) is a heterogeneous group of inherited dental enamel defects. It has rarely been reported in association with multiorgan syndromes and metabolic disorders. The metabolic disorders that have been reported in association with AI include hypocalciuria, impaired urinary concentrating ability, and Bartter-like syndrome. In literature, only three cases of AI and distal renal tubular acidosis (dRTA) have been described: two cases in adults and a solitary case in the pediatric age group. Here, we report a child with AI presenting with dRTA; to the best of our knowledge, our reported case is the only second such case in pediatric age group. Our case highlights the importance of recognizing the possibility of renal abnormalities in patients with AI as it will affect the long-term prognosis.

  1. Amelogenesis imperfecta with distal renal tubular acidosis: A novel syndrome?

    Directory of Open Access Journals (Sweden)

    R A Misgar

    2017-01-01

    Full Text Available Amelogenesis imperfecta (AI is a heterogeneous group of inherited dental enamel defects. It has rarely been reported in association with multiorgan syndromes and metabolic disorders. The metabolic disorders that have been reported in association with AI include hypocalciuria, impaired urinary concentrating ability, and Bartter-like syndrome. In literature, only three cases of AI and distal renal tubular acidosis (dRTA have been described: two cases in adults and a solitary case in the pediatric age group. Here, we report a child with AI presenting with dRTA; to the best of our knowledge, our reported case is the only second such case in pediatric age group. Our case highlights the importance of recognizing the possibility of renal abnormalities in patients with AI as it will affect the long-term prognosis.

  2. Factor H and Properdin Recognize Different Epitopes on Renal Tubular Epithelial Heparan Sulfate

    NARCIS (Netherlands)

    Zaferani, Azadeh; Vives, Romain R.; van der Pol, Pieter; Navis, Gerjan J.; Daha, Mohamed R.; van Kooten, Cees; Lortat-Jacob, Hugues; Seelen, Marc A.; van den Born, Jacob

    2012-01-01

    During proteinuria, renal tubular epithelial cells become exposed to ultrafiltrate-derived serum proteins, including complement factors. Recently, we showed that properdin binds to tubular heparan sulfates (HS). We now document that factor H also binds to tubular HS, although to a different epitope

  3. Effect of Diuretics on Renal Tubular Transport of Calcium and Magnesium

    DEFF Research Database (Denmark)

    Alexander, R Todd; Dimke, Henrik

    2017-01-01

    are important for both forming divalent cation permeable pores and channels, but also for generating the necessary driving forces for Ca2+ and Mg2+ transport. Alterations in these molecular constituents lead to profound effects on tubular Ca2+ and Mg2+ handling. Diuretics are used to treat a large range...... of clinical conditions, but most commonly for the management of blood pressure and fluid balance. The pharmacological targets of diuretics generally directly facilitate sodium (Na+) transport, but also indirectly affect renal Ca2+ and Mg2+ handling, i.e. by establishing a prerequisite electrochemical gradient....... It is therefore not surprising that substantial alterations in divalent cation handling can be observed following diuretic treatment. The effects of diuretics on renal Ca2+ and Mg2+ handling are reviewed in the context of the current understanding of basal molecular mechanisms of Ca2+ and Mg2+ transport...

  4. Renal haemodynamics, sodium and water reabsorption during continuous intravenous infusion of recombinant interleukin-2

    DEFF Research Database (Denmark)

    Geertsen, P F; von der Maase, H; Olsen, Niels Vidiendal

    1998-01-01

    1. Renal haemodynamics, lithium and sodium clearance were measured in 14 patients treated with recombinant interleukin-2 for metastatic renal cell carcinoma. 2. Patients were studied before and after 72 h of continuous intravenous infusion of recombinant interleukin-2 (18x10(6) i.u..24 h-1.m-2) a...... effect. Changes in renal prostaglandin synthesis may contribute to the decrease in renal blood flow. The lithium clearance data suggest that an increased proximal tubular reabsorption rate may contribute to the decreased sodium clearance during recombinant interleukin-2 treatment....

  5. Recombinant human erythropoietin in humans down-regulates proximal renal tubular reabsorption and causes a fall in glomerular filtration rate

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Aachmann-Andersen, Niels Jacob; Oturai, Peter

    2010-01-01

    HuEPO for 28 days in doses raising the hematocrit to 48.3 (4.1) %. Renal clearance studies with urine collections (N = 8) were done at baseline and at days 4, 11, 29, and 42. Glomerular filtration rate (GFR) was measured by (51)Cr-EDTA. Renal clearance of lithium (C(Li)) was used as an index of proximal...... tubular outflow and to assess segmental renal tubular handling of sodium and water. rHuEPO-induced increases in hematocrit occurred from day 10 onwards and was caused by both an increase in red cell volume and a fall in plasma volume. Well before that (from day 2 and throughout the treatment time), r...... and water (APR = GFR - C(Li), P

  6. Endogenous versus exogenous lithium clearance for evaluation of dopamine-induced changes in renal tubular function

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Fogh-Andersen, N; Strandgaard, S

    1996-01-01

    1. The present randomized, double-blind cross-over study compared endogenous and exogenous lithium clearance (CLi) for estimation of the effect of dopamine on tubular sodium reabsorption. Twelve normal, salt-repleted male subjects were investigated on three different occasions with either placebo...... or 450 mg or 600 mg of lithium given in random order at 22.00 hours. After an overnight fast, renal clearance studies were performed during a 1 h baseline period and subsequently during the second hour of an infusion of 3 micrograms min-1 kg-1 of dopamine. 2. Baseline values of endogenous CLi.......3-31.0)% (P lithium increased the baseline sodium clearance (CNa), but glomerular filtration rate and urine flow rate remained unchanged. 3. Dopamine increased CNa to similar values on the three study days. CLi increased to 40.9 (35.5-46.5) ml/min (endogenous lithium, P

  7. Renal handling of sodium and water in the hypothyroid rat

    Science.gov (United States)

    Michael, Ulrich F.; Barenberg, Robert L.; Chavez, Rafaelita; Vaamonde, Carlos A.; Papper, Solomon

    1972-01-01

    Hypothyroid rats were examined with conventional renal clearance and micropuncture techniques to elicit the mechanism and site within the nephron responsible for the increased salt and water excretion observed in these animals. When compared with age-matched control rats, a decrease in inulin clearance of 30% (P < 0.001) and in Hippuran clearance of 32% (P < 0.005) was observed in the hypothyroid rats. Absolute excretion of sodium and water was increased 3-fold (P < 0.02) and 2-fold (P < 0.025), respectively, while fractional excretion of sodium and water was increased 4.3-fold (P < 0.02) and 2.9-fold (P < 0.05), respectively, in the hypothyroid animals. Fractional proximal reabsorption of sodium as assessed from proximal tubular fluid to plasma ratios of inulin ([TF/P]IN) was found to be decreased by 28% (P < 0.001) in the hypothyroid rats. Superficial single nephron filtration rate was reduced proportionately to the decrease in total filtration rate in the hypothyroid rats. These data indicate that the proximal tubule is one of the sites of diminished sodium and water reabsorption in the hypothyroid rat. The data also suggest that the observed decrease in glomerular filtration rate in the hypothyroid animals is not caused by a decrease in the number of functioning nephrons and that the observed increase in sodium and water excretion is not caused by a redistribution of filtrate from juxtamedullary to superficial nephrons. Although the exact mechanisms of the observed changes in proximal tubular function remain unknown, the data suggest that they are probably related to the lack of thyroid hormone. Whatever their mechanism, it appears that the enhanced sodium and water excretion observed in the hypothyroid animals must be determined by further reduction in tubular sodium reabsorption in the distal nephron. PMID:5024038

  8. Renal tubular dysfunction in pediatric patients with beta-thalassemia major

    Directory of Open Access Journals (Sweden)

    Ali Ahmadzadeh

    2011-01-01

    Full Text Available To evaluate the prevalence of renal tubular dysfunction in children with β-thalassemia (β-T major, we studied the glomerular and tubular function in 140 children with β-T major and compared them to a healthy control group at our center from May 2007 to April 2008. Fresh first morning samples were collected from each patient and analyzed for sodium, potassium, calcium (Ca, protein, uric acid (UA, creatinine (Cr, urine osmolality and urinary N-acetyl-β-D-glucosaminidase (UNAG activity. Blood samples were also collected for complete blood count, blood urea nitrogen (BUN, fasting blood sugar, serum creatinine (SCr, electrolytes, and ferritin before transfusion. Among the study patients, 72 were males, and the mean age was 11.5 (ranging 7-16 years. SCr levels were all within normal limits and all of them had normal glomerular filtration rate (GFR. The mean UNAG was 17.8 IU/L in the study patients (normal 0.15-11.5 IU/L and 3.2 IU/L in the control group (P 0.21 (P = 0.006. Nine (6.4% thalassemic patients with a mean age of 12 years had proteinuria (Upr/UCr > 0.2. Sixty-nine (49.3% out of the 140 patients and 45 (65.2% of the patients having UNAG had uricosuria also (UUA/UCr > 0.26. Ten (7% patients had microscopic hematuria and 10 (7% patients with a mean age of 13.5 years had glucosuria or diabetes mellitus. We conclude that tubular dysfunction is a relative common complication of the β-T major; UNAG and its index are the best to detect renal tubular dysfunction in these patients. Currently, periodic measurement of UCa/UCr and UUA/UCr ratios as well as urinalysis are recommended.

  9. Stem cell factor expression after renal ischemia promotes tubular epithelial survival.

    Directory of Open Access Journals (Sweden)

    Geurt Stokman

    Full Text Available BACKGROUND: Renal ischemia leads to apoptosis of tubular epithelial cells and results in decreased renal function. Tissue repair involves re-epithelialization of the tubular basement membrane. Survival of the tubular epithelium following ischemia is therefore important in the successful regeneration of renal tissue. The cytokine stem cell factor (SCF has been shown to protect the tubular epithelium against apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: In a mouse model for renal ischemia/reperfusion injury, we studied how expression of c-KIT on tubular epithelium and its ligand SCF protect cells against apoptosis. Administration of SCF specific antisense oligonucleotides significantly decreased specific staining of SCF following ischemia. Reduced SCF expression resulted in impaired renal function, increased tubular damage and increased tubular epithelial apoptosis, independent of inflammation. In an in vitro hypoxia model, stimulation of tubular epithelial cells with SCF activated survival signaling and decreased apoptosis. CONCLUSIONS/SIGNIFICANCE: Our data indicate an important role for c-KIT and SCF in mediating tubular epithelial cell survival via an autocrine pathway.

  10. Effect of cisplatin on renal haemodynamics and tubular function in the dog kidney

    DEFF Research Database (Denmark)

    Daugaard, G; Abildgaard, U; Holstein-Rathlou, N H

    1987-01-01

    Administration of cisplatin (5 mg/kg) to dogs results in polyuric renal failure due initially to a proximal tubular functional impairment. 48-72 h after the cisplatin administration the depressed renal function can be attributed to impairment of proximal as well as distal tubular reabsorptive cap...... capacities associated with increased renal vascular resistance. The polyuria seems to be due to the impaired reabsorption rate in the distal nephron segments....

  11. Osteomalacia complicating renal tubular acidosis in association with Sjogren's syndrome.

    Science.gov (United States)

    El Ati, Zohra; Fatma, Lilia Ben; Boulahya, Ghada; Rais, Lamia; Krid, Madiha; Smaoui, Wided; Maiz, Hedi Ben; Beji, Soumaya; Zouaghi, Karim; Moussa, Fatma Ben

    2014-09-01

    Renal involvement in Sjogren's syndrome (SS) is not uncommon and may precede other complaints. Tubulointerstitial nephritis is the most common renal disease in SS and may lead to renal tubular acidosis (RTA), which in turn may cause osteomalacia. Nevertheless, osteomalacia rarely occurs as the first manifestation of a renal tubule disorder due to SS. We herewith describe a 43-year-old woman who was admitted to our hospital for weakness, lumbago and inability to walk. X-ray of the long bones showed extensive demineralization of the bones. Laboratory investigations revealed chronic kidney disease with serum creatinine of 2.3 mg/dL and creatinine clearance of 40 mL/min, hypokalemia (3.2 mmol/L), hypophosphatemia (0.4 mmol/L), hypocalcemia (2.14 mmol/L) and hyperchloremic metabolic acidosis (chlorine: 114 mmol/L; alkaline reserve: 14 mmol/L). The serum alkaline phosphatase levels were elevated. The serum levels of 25-hydroxyvitamin D and 1,25-dihydroxy vitamin D were low and borderline low, respectively, and the parathyroid hormone level was 70 pg/L. Urinalysis showed inappropriate alkaline urine (urinary PH: 7), glycosuria with normal blood glucose, phosphaturia and uricosuria. These values indicated the presence of both distal and proximal RTA. Our patient reported dryness of the mouth and eyes and Schirmer's test showed xerophthalmia. An accessory salivary gland biopsy showed changes corresponding to stage IV of Chisholm and Masson score. Kidney biopsy showed diffuse and severe tubulo-interstitial nephritis with dense lymphoplasmocyte infiltrates. Sicca syndrome and renal interstitial infiltrates indicated SS as the underlying cause of the RTA and osteomalacia. The patient received alkalinization, vitamin D (Sterogyl ®), calcium supplements and steroids in an initial dose of 1 mg/kg/day, tapered to 10 mg daily. The prognosis was favorable and the serum creatinine level was 1.7 mg/dL, calcium was 2.2 mmol/L and serum phosphate was 0.9 mmol/L.

  12. Hypokalaemia and Renal Tubular Acidosis due to Abuse of Nurofen Plus

    Directory of Open Access Journals (Sweden)

    M. J. Blackstock

    2012-01-01

    Full Text Available Nurofen Plus is a common analgesic containing ibuprofen and codeine. We present a case of a 38-year-old lady who developed renal tubular acidosis with severe hypokalaemia, after chronic abuse of Nurofen Plus tablets. She presented with confusion and profound biochemical abnormalities requiring critical care admission for electrolyte replacement. Ibuprofen causes renal tubular acidosis due to its effects on carbonic anhydrase activity.

  13. Prevalence of renal tubular dysfunction in beta thalassemia minor in shiraz

    Directory of Open Access Journals (Sweden)

    Ali Moradi Nakhodcheri

    2012-02-01

    Full Text Available  Background & objective: β-Thalassemia minor is an asymptomatic hereditary disease. The first study on the relation of renal tubular dysfunction and β-thalassemia minor was performed in 2002 but those studies seem inadequate.The main goal of this study is through evaluation of renal tubular function in 100 patients with thalassemia minor. Materials & Methods: 100 patients with β- thalassemia which confirmed by hemoglobin electrophoresis and CBC as well as RBC indices were studied.14 out of 100 cases exit because of Urinary Tract Infection, diabetes mellitus or hypertension.Complete chemistry profile was performed on serum and urine of all reminder 86 patients (46 female and 40 male. Patients classified into two groups: β-thalassemia minor with anemia and without anemia. Another control group include 50 healthy individuals also considered.Then data analyzed by proper statistical methods. Results: 20 out of 86 reminder cases e.g. 24% showed at least one index of renal tubular dysfunction.58% of patients was been anemic and 42% non anemic. The most prominent tubular dysfunction was seen in a 29 years old lady with glucosuria and without anemia. conclusion: β-Thalassemia minor is common in Iran specially in Fars province. This study revealed significant renal tubular dysfunction in patient with β-thalassemia minor. So it is necessary to check out thalassemic patients for renal function tests periodically. Key words: β-thalassemia, minor,renal tubular dysfunction

  14. Hyperammonemia associated with distal renal tubular acidosis or urinary tract infection: a systematic review.

    Science.gov (United States)

    Clericetti, Caterina M; Milani, Gregorio P; Lava, Sebastiano A G; Bianchetti, Mario G; Simonetti, Giacomo D; Giannini, Olivier

    2018-03-01

    Hyperammonemia usually results from an inborn error of metabolism or from an advanced liver disease. Individual case reports suggest that both distal renal tubular acidosis and urinary tract infection may also result in hyperammonemia. A systematic review of the literature on hyperammonemia secondary to distal renal tubular acidosis and urinary tract infection was conducted. We identified 39 reports on distal renal tubular acidosis or urinary tract infections in association with hyperammonemia published between 1980 and 2017. Hyperammonemia was detected in 13 children with distal renal tubular acidosis and in one adult patient with distal renal tubular acidosis secondary to primary hyperparathyroidism. In these patients a negative relationship was observed between circulating ammonia and bicarbonate levels (P urinary tract infection was complicated by acute hyperammonemia and symptoms and signs of acute neuronal dysfunction, such as an altered level of consciousness, convulsions and asterixis, often associated with signs of brain edema, such as anorexia and vomiting. Urea-splitting bacteria were isolated in 28 of the 31 cases. The urinary tract was anatomically or functionally abnormal in 30 of these patients. This study reveals that both altered distal renal tubular acidification and urinary tract infection may be associated with relevant hyperammonemia in both children and adults.

  15. Distal renal tubular acidosis in two children with acquired hypothyroidism.

    Science.gov (United States)

    Guerra-Hernández, Norma E; Ordaz-López, Karen V; Vargas-Poussou, Rosa; Escobar-Pérez, Laura; García-Nieto, Víctor M

    2018-04-28

    Two cases of children diagnosed with renal tubular acidosis (RTA) associated with autoimmune hypothyroidism are presented. Case 1 developed an intestinal ileus at the age of five in the context of a respiratory problem. The tests performed confirmed metabolic acidosis, hyperchloraemia, hypokalaemia and nephrocalcinosis. Case 2 was diagnosed with hypothyroidism at the age of 11, and with RTA two years later. In both patients, the diagnosis of RTA was verified when decreased maximum urinary pCO 2 was found. In case 2, a proximal bicarbonate leak (type 3 RTA) was also confirmed. This was the first case to be published on the topic. The causes of RTA in patients with hypothyroidism are reviewed. The deleterious effect on the kidneys may be due to the absence of thyroid hormone and/or autoantibodies in the cases of autoimmune hypothyroidism. Copyright © 2018 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  16. Quantitation of renal function with glomerular and tubular agents

    International Nuclear Information System (INIS)

    Dubovsky, E.V.; Russell, C.D.

    1982-01-01

    Quantitative methods to measure the glomerular and tubular function of the kidneys with radionuclides have been available for many years. They have not been widely used because the techniques and the calculations exceeded the scope of routine nuclear medicine practice. Validation of simplified methods and the introduction of computer technology have made measurement of the effective renal plasma flow (ERPF) and the glomerular filtration rate (GFR) simple enough so that they can be performed reproducibly in most nuclear medicine departments. The estimation of ERPF with radioiodinated OIH and GFR with /sup 99m/TcDTPA can be achieved in many ways, all of which yield clinically useful results. How to get the best results using the simplest methods is still unclear. The required accuracy depends on the intended clinical use. Our preference at the present time is to use a single or double plasma sample to calculate global ERPF or GFR, and to use the 1-2 min OIH or 1-3 min Tc-DTPA uptake to calculate relative function of the two kidneys (split function ERPF or GFR). The choice of method will be influenced by local factors, such as the nature of the patient population, the case volume, and the resources available. A desirable goal for future studies is to document carefully the capabilities and limitations of each alternative method, so that the choice can be rational

  17. The effects of cimetidine on creatinine excretion, glomerular filtration rate and tubular function in renal transplant recipients

    DEFF Research Database (Denmark)

    Olsen, N V; Ladefoged, S D; Feldt-Rasmussen, B

    1989-01-01

    The renal clearance of endogenous creatinine (CCr), sodium (CNa) and lithium (CLi) was determined before and after a single intravenous bolus of cimetidine in nine renal transplant recipients. The glomerular filtration rate (GFR) was measured with 125I-iothalamate clearance (CTh). The initial CCr...... of 65 ml/min (median) was reduced to a nadir of 46 ml/min (p less than 0.01) during the first 2 h after infusion of cimetidine. GFR remained unchanged, and thus the fractional clearance of creatinine (CCr/CTh) was reduced from 1.43 (median) to 1.03 (p less than 0.01). CNa and the fractional excretion...... of sodium decreased throughout the study (p less than 0.05); CLi was unchanged. In conclusion cimetidine, when measured during 1-h clearance periods, interferes with tubular creatinine secretion in the denervated kidney of transplant recipients without affecting the glomerular filtration rate or proximal...

  18. Insulin's acute effects on glomerular filtration rate correlate with insulin sensitivity whereas insulin's acute effects on proximal tubular sodium reabsorption correlate with salt sensitivity in normal subjects

    NARCIS (Netherlands)

    ter Maaten, JC; Bakker, SJL; Serne, EH; ter Wee, PM; Gans, ROB

    1999-01-01

    Background. Insulin induces increasing distal tubular sodium reabsorption. Opposite effects of insulin to offset insulin-induced sodium retention are supposedly increases in glomerular filtration rate (GFR) and decreases in proximal tubular sodium reabsorption. Defects in these opposing effects

  19. Effect of diuretics on renal tubular transport of calcium and magnesium.

    Science.gov (United States)

    Alexander, R Todd; Dimke, Henrik

    2017-06-01

    Calcium (Ca 2+ ) and Magnesium (Mg 2+ ) reabsorption along the renal tubule is dependent on distinct trans- and paracellular pathways. Our understanding of the molecular machinery involved is increasing. Ca 2+ and Mg 2+ reclamation in kidney is dependent on a diverse array of proteins, which are important for both forming divalent cation-permeable pores and channels, but also for generating the necessary driving forces for Ca 2+ and Mg 2+ transport. Alterations in these molecular constituents can have profound effects on tubular Ca 2+ and Mg 2+ handling. Diuretics are used to treat a large range of clinical conditions, but most commonly for the management of blood pressure and fluid balance. The pharmacological targets of diuretics generally directly facilitate sodium (Na + ) transport, but also indirectly affect renal Ca 2+ and Mg 2+ handling, i.e., by establishing a prerequisite electrochemical gradient. It is therefore not surprising that substantial alterations in divalent cation handling can be observed following diuretic treatment. The effects of diuretics on renal Ca 2+ and Mg 2+ handling are reviewed in the context of the present understanding of basal molecular mechanisms of Ca 2+ and Mg 2+ transport. Acetazolamide, osmotic diuretics, Na + /H + exchanger (NHE3) inhibitors, and antidiabetic Na + /glucose cotransporter type 2 (SGLT) blocking compounds, target the proximal tubule, where paracellular Ca 2+ transport predominates. Loop diuretics and renal outer medullary K + (ROMK) inhibitors block thick ascending limb transport, a segment with significant paracellular Ca 2+ and Mg 2+ transport. Thiazides target the distal convoluted tubule; however, their effect on divalent cation transport is not limited to that segment. Finally, potassium-sparing diuretics, which inhibit electrogenic Na + transport at distal sites, can also affect divalent cation transport. Copyright © 2017 the American Physiological Society.

  20. Sodium bicarbonate loading limits tubular cast formation independent of glomerular injury and proteinuria in dahl salt-sensitive rats.

    Science.gov (United States)

    Ray, S C; Patel, B; Irsik, D L; Sun, J; Ocasio, H; Crislip, G R; Jin, C H; Chen, J K; Baban, B; Polichnowski, A J; O'Connor, P M

    2018-04-12

    Sodium bicarbonate (NaHCO 3 ) slows the decline in kidney function in patients with chronic kidney disease (CKD), yet the mechanisms mediating this effect remain unclear. The Dahl salt-sensitive (SS) rat develops hypertension and progressive renal injury when fed a high salt diet; however, the effect of alkali loading on kidney injury has never been investigated in this model. We hypothesized that 'NaHCO 3 protects from the development of renal injury in Dahl salt-sensitive rats via luminal alkalization which limits the formation of tubular casts, which are a prominent pathological feature in this model. To examine this hypothesis, we determined blood pressure and renal injury responses in Dahl SS rats drinking vehicle (0.1M NaCl) or NaHCO 3 (0.1M) solutions as well as in Dahl SS rats lacking the voltage gated proton channel (Hv1). We found that oral NaHCO 3 reduced tubular NH 4 + production, tubular cast formation and interstitial fibrosis in rats fed a high salt diet for 2 weeks. This effect was independent of changes in blood pressure, glomerular injury or proteinuria and did not associate with changes in renal inflammatory status. We found that null mutation of Hv1 also limited cast formation in Dahl SS rats independent of proteinuria or glomerular injury. As Hv1 is localized to the luminal membrane of TAL, our data, suggest that alkalization of the luminal fluid within this segment limits cast formation in this model. Reduced cast formation, secondary to luminal alkalization within TAL segments may mediate some of the protective effects of alkali loading observed in CKD patients. ©2018 The Author(s).

  1. Cleistanthus collinus induces type I distal renal tubular acidosis and type II respiratory failure in rats.

    Science.gov (United States)

    Maneksh, Delinda; Sidharthan, Anita; Kettimuthu, Kavithapriya; Kanthakumar, Praghalathan; Lourthuraj, Amala A; Ramachandran, Anup; Subramani, Sathya

    2010-06-01

    A water decoction of the poisonous shrub Cleistanthus collinus is used for suicidal purposes. The mortality rate is 28%. The clinical profile includes distal renal tubular acidosis (DRTA) and respiratory failure. The mechanism of toxicity is unclear. To demonstrate features of C. collinus toxicity in a rat model and to identify its mechanism(s) of action. Rats were anesthetized and the carotid artery was cannulated. Electrocardiogram and respiratory movements were recorded. Either aqueous extract of C. collinus or control solution was administered intraperitoneally. Serial measurements of blood gases, electrolytes and urinary pH were made. Isolated brush border and basolateral membranes from rat kidney were incubated with C. collinus extract and reduction in ATPase activity was assessed. Venous blood samples from human volunteers and rats were incubated with an acetone extract of C. collinus and plasma potassium was estimated as an assay for sodium-potassium pump activity. The mortality was 100% in tests and 17% in controls. Terminal event in test animals was respiratory arrest. Controls had metabolic acidosis, respiratory compensation acidic urine and hyperkalemia. Test animals showed respiratory acidosis, alkaline urine and low blood potassium as compared to controls. C. collinus extract inhibited ATPase activity in rat kidney. Plasma K(+) did not increase in human blood incubated with C. collinus extract. Active principles of C. collinus inhibit proton pumps in the renal brush border, resulting in type I DRTA in rats. There is no inhibition of sodium-potassium pump activity. Test animals develop respiratory acidosis, and the immediate cause of death is respiratory arrest.

  2. Autoimmune Hepatitis with Distal Renal Tubular Acidosis and Small Bowel Partial Malrotation.

    Science.gov (United States)

    Kanaiyalal Modi, Tejas; Parikh, Hardik; Sadalge, Abhishek; Gupte, Amit; Bhatt, Pratin; Shukla, Akash

    2015-01-01

    Renal tubular acidosis (RTA) is not uncommon in patient with chronic autoimmune hepatitis (AIH), but usually remains latent. Here, we report a case of renal tubular acidosis RTA who presented with AIH. She was also diagnosed to have partial bowel malrotation. A 9-year-old girl, a case of distal RTA, presented with jaundice, abdominal distension and altered sensorium. She was diagnosed to be AIH, which was successfully treated with steroids and azathioprine. Coexistent midgut partial malrotation with volvulus was diagnosed during the treatment. She was treated successfully with anti-tuberculous treatment for cervical lymphadenitis. Autoimmune hepatitis should not be ruled out in each case of RTA presenting with jaundice. Modi TK, Parikh H, Sadalge A, Gupte A, Bhatt P, Shukla A. Autoimmune Hepatitis with Distal Renal Tubular Acidosis and Small Bowel Partial Malrotation. Euroasian J Hepato-Gastroenterol 2015;5(2):107-109.

  3. Tumor-promoting phorbol esters effect alkalinization of canine renal proximal tubular cells

    International Nuclear Information System (INIS)

    Mellas, J.; Hammerman, M.R.

    1986-01-01

    We have demonstrated the presence of specific receptors for tumor-promoting phorbol esters in the plasma membrane of the canine renal proximal tubular cell. These compounds affect proximal tubular metabolism in vitro. For example, we have shown that they inhibit gluconeogenesis in canine renal proximal tubular segments. Tumor-promoting phorbol esters have been shown to effect alkalinization of non-renal cells, by enhancing Na + -H + exchange across the plasma membrane. To determine whether the actions of tumor-promoting phorbol esters in proximal tubular segments might be mediated by a similar process, we incubated suspensions of segments from dog kidney with these compounds and measured changes in intracellular pH using [ 14 C]-5,5-dimethoxazoladine-2-4-dione (DMO) and flow dialysis. Incubation of segments with phorbol 12,13 dibutyrate, but not inactive phorbol ester, 4 γ phorbol, effected alkalinization of cells within the segments in a concentration-dependent manner. Alkalinization was dependent upon the presence of extracellular [Na + ] > intracellular [Na + ], was prevented by amiloride and was demonstrable in the presence of SITS. Our findings suggest that tumor-promoting esters stimulate the Na + -H + exchanger known to be present in the brush border membrane of the renal proximal tubular cell. It is possible that the stimulation reflects a mechanism by which phorbol esters affect metabolic processes in these cells

  4. Renal tubular dysfunction presenting as recurrent hypokalemic periodic quadriparesis in systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    D Prasad

    2014-01-01

    Full Text Available We report recurrent hypokalemic periodic quadriparesis in a 30-year-old woman. Patient had also symptoms of multiple large and small joint pain, recurrent oral ulceration, photosensitivity and hair loss that were persisting since last 6 months and investigations revealed systemic lupus erythematosus (SLE with distal tubular acidosis. Our patient was successfully treated with oral potassium chloride, sodium bicarbonate, hydroxychloroquine and a short course of steroids. Thus, tubular dysfunction should be carefully assessed in patients with SLE.

  5. Renal Impairment with Sublethal Tubular Cell Injury in a Chronic Liver Disease Mouse Model.

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    Tokiko Ishida

    Full Text Available The pathogenesis of renal impairment in chronic liver diseases (CLDs has been primarily studied in the advanced stages of hepatic injury. Meanwhile, the pathology of renal impairment in the early phase of CLDs is poorly understood, and animal models to elucidate its mechanisms are needed. Thus, we investigated whether an existing mouse model of CLD induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC shows renal impairment in the early phase. Renal injury markers, renal histology (including immunohistochemistry for tubular injury markers and transmission electron microscopy, autophagy, and oxidative stress were studied longitudinally in DDC- and standard diet-fed BALB/c mice. Slight but significant renal dysfunction was evident in DDC-fed mice from the early phase. Meanwhile, histological examinations of the kidneys with routine light microscopy did not show definitive morphological findings, and electron microscopic analyses were required to detect limited injuries such as loss of brush border microvilli and mitochondrial deformities. Limited injuries have been recently designated as sublethal tubular cell injury. As humans with renal impairment, either with or without CLD, often show almost normal tubules, sublethal injury has been of particular interest. In this study, the injuries were associated with mitochondrial aberrations and oxidative stress, a possible mechanism for sublethal injury. Intriguingly, two defense mechanisms were associated with this injury that prevent it from progressing to apparent cell death: autophagy and single-cell extrusion with regeneration. Furthermore, the renal impairment of this model progressed to chronic kidney disease with interstitial fibrosis after long-term DDC feeding. These findings indicated that DDC induces renal impairment with sublethal tubular cell injury from the early phase, leading to chronic kidney disease. Importantly, this CLD mouse model could be useful for studying the

  6. Pathophysiology of incomplete renal tubular acidosis in recurrent renal stone formers: evidence of disturbed calcium, bone and citrate metabolism

    DEFF Research Database (Denmark)

    Osther, P J; Bollerslev, Jens; Hansen, A B

    1993-01-01

    Urinary acidification, bone metabolism and urinary excretion of calcium and citrate were evaluated in 10 recurrent stone formers with incomplete renal tubular acidosis (iRTA), 10 recurrent stone formers with normal urinary acidification (NUA) and 10 normal controls (NC). Patients with iRTA had...

  7. Diffuse Lymphomatous Infiltration of Kidney Presenting as Renal Tubular Acidosis and Hypokalemic Paralysis: Case Report

    Science.gov (United States)

    Jhamb, Rajat; Gupta, Naresh; Garg, Sandeep; Kumar, Sachin; Gulati, Sameer; Mishra, Deepak; Beniwal, Pankaj

    2007-01-01

    We report the case of a 22-year-old woman who presented with acute onset flaccid quadriparesis. Physical examination showed mild pallor with cervical and axillary lymphadenopathy, hepatomegaly, and bilateral smooth enlarged kidneys. Neurological examination revealed lower motor neuron muscle weakness in all the four limbs with hyporeflexia and normal sensory examination. Laboratory investigations showed anemia, severe hypokalemia, and metabolic acidosis. Urinalysis showed a specific gravity of 1.010, pH of 7.0, with a positive urine anion gap. Ultrasound revealed hepatosplenomegaly with bilateral enlarged smooth kidneys. Renal biopsy was consistent with the diagnosis of non-Hodgkin lymphoma (B cell type). Metabolic acidosis, alkaline urine, and severe hypokalemia due to excessive urinary loss in our patient were suggestive of distal renal tubular acidosis. Renal involvement in lymphoma is usually subclinical and clinically overt renal disease is rare. Diffuse lymphomatous infiltration of the kidneys may cause tubular dysfunction and present with hypokalemic paralysis. PMID:18074421

  8. Renal Tubular Acidosis Secondary to FK506 in Living Donor Liver Transplantation: A Case Report

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    Keiko Ogita

    2003-10-01

    Full Text Available FK506 is an immunosuppressant that is thought to be less nephrotoxic than cyclosporine A. However, complications due to renal tubular acidosis (RTA have recently been reported. We report a case of RTA secondary to FK506 administration in liver transplantation. A 6-month-old girl was treated with FK506 after undergoing living donor liver transplantation for fulminant hepatitis. On postoperative day 17, she demonstrated hyperkalaemia and metabolic acidosis; she was diagnosed to have hyperkalaemic distal RTA with aldosterone deficiency (type IV. Intravenous sodium bicarbonate and furosemide, and intrarectal calcium polystyrenesulfonate were administered to correct the acidosis and promote potassium secretion. Thereafter, the FK506 concentration in whole blood gradually decreased, and the hyperkalaemia and metabolic acidosis following RTA improved. RTA is one type of nephrotoxicity induced by FK506, and it is reversible in mild cases when appropriately treated. The mechanism of RTA induced by FK506 has not yet been clearly elucidated. Surgeons and physicians should therefore be aware of the potential for RTA to occur with FK506 after any organ transplantation. The treatment for acidosis and hyperkalaemia should be started as soon as RTA is diagnosed, and the dosage of FK506 should also be reduced if possible.

  9. Renal tubular dysfunction nephrocalcinosis in a patient with BetaThalassemia Minor

    International Nuclear Information System (INIS)

    Prabahar, M.R.; Jain, M.; Chandrasekaran, V.; Indumathi, E.; Soundrarajan, P.

    2008-01-01

    Thalassemia is a hereditary anemia resulting from defect in hemoglobinproduction. Beta thalassemia is due to impaired production. Beta thalassemiais due to impaired production of beta globin chains, leading to a relativeexcess of alpha globin chains. The term beta thalassemia minor is used todescribe heterozygotes, who carry one normal beta globin and one betathalassemic allele. The vast majority of these patients are asymptomatic.However, a variety of renal tubular abnormalities including hypercaliuria,hypomagnesemia with renal magnesium wasting, decreased tubular absorption ofphosphorous, hypouricemia with renal uric acid wasting, renal glycosuria andtubular proteinuria have been described even in patients with betathalassemia minor. We here in report a 24-year old patient who was found tohave thalassemia minor and nephrocalcinosis with evidence of renal tubulardysfunction. Investigations revealed normal renal function, hypercalciuria,reduced tubular reabsorption of phosphorous, hypomagnesemia and renalmagnesium wasting. Screening for aminoaciduria was found to be negative. Anacid loading test revealed normal urinary acidification. Ultrasonogram of theabdomen revealed nephrocalcinosis and splenomegaly. Detailed work up foranemia showed normal white cell and platelet count while peripheral smearshowed microcytic hypochromic anemia with few target cells. Hemoglobinelectrophoresis revealed hemoglobin A of 92%, hemoglobin A2 of 6.2% andhemoglobin F of 1.8% consistent with beta thalassemia minor. Her parentalscreening was normal. A diagnosis of beta thalassemia minor with renaltubular dysfunction was made and the patient was started on thiazidediuretics to reduce hypercalciuria and advised regular follow-up. (author)

  10. Whole‐exome sequencing as a diagnostic tool for distal renal tubular acidosis

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    Paula Cristina Barros Pereira

    2015-11-01

    Conclusion: These results confirm the value of whole‐exome sequencing for the study of rare and complex genetic nephropathies, allowing the identification of novel and recurrent mutations. Furthermore, for the first time the application of this molecular method in renal tubular diseases has been clearly demonstrated.

  11. The proximal tubular cell, a key player in renal damage

    NARCIS (Netherlands)

    Timmeren, Mirjan Miranda van

    2008-01-01

    A decline in renal function is associated with the degree of proteinuria and with histological findings of glomerulosclerosis and interstitial fibrosis. Proteinuria is not only a marker of renal damage, but ultrafiltered proteins can be toxic to the kidney, thereby contributing to

  12. A Mathematical Model of Renal Blood Distribution Coupling TGF, MR and Tubular System

    Institute of Scientific and Technical Information of China (English)

    GAO Ci-xiu; YANG Lin; WANG Ke-qiang; XU Shi-xiong; DAI Pei-dong

    2009-01-01

    Objective:To investigate the relationship between renal blood distribution and the physiological activities of the kidney. Methods:A mathematical model is developed based on Hagan-Poiseuille law and mass transport, coupling mechanics of myogenic response (MR), tubuloglomerular feedback (TGF) and the tubular system in the renal medulla. The model parameters, including the permeability coefficients, the vascular lumen radius and the solute concentration at the inlet of the tubes, are derived from the experimental results. Simulations of the blood and water flow in the loop of Henel, the collecting duct and vas rectum, are carried out by the model of the tubular system in the renal medulla, based on conservations of water and solutes for transmural transport. Then the tubular model is coupled with MR and TGF mechanics. Results:The results predict the dynamics of renal autoregulation on its blood pressure and flow,and the distributions are 88.5% in the cortex, 10.3% in the medulla, and 1.2% at papilla,respectively. The fluid flow and solute concentrations along the tubules and vasa recta are obtained. Conclusion:The present model could assess renal functions qualitatively and quantitatively and provide a methodological approach for clinical research.

  13. The influence of angiotensin-converting enzyme inhibition on renal tubular function in progressive chronic nephropathy

    DEFF Research Database (Denmark)

    Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P

    1996-01-01

    The influence of angiotensin-converting enzyme (ACE) inhibition on renal tubular function in progressive chronic nephropathy was investigated in 69 patients by the lithium clearance (C(Li)) method. Studies were done repeatedly for up to 2 years during a controlled trial on the effect of enalapril...... on progression of renal failure. The pattern of proteinuria was followed over the first 9 months. At baseline, the glomerular filtration rate (GFR) was 5 to 68 mL/min. Absolute proximal tubular reabsorption rate of fluid (APR), estimated as the difference between GFR and C(Li), was 1 to 54 mL/min. Calculated...... in either treatment regimen was associated with a long-term slower progression of renal failure. Over 9 months, the 24-hour fractional clearance of albumin decreased in the ACE inhibitor group (P

  14. Clinical profile and outcome of renal tubular disorders in children: A single center experience

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    B Vijay Kiran

    2014-01-01

    Full Text Available Tubular disorders form a significant proportion of pediatric kidney diseases and are an important differential diagnosis of failure to thrive (FTT in children. Data regarding their outcome is scarce from India. We evaluated the clinical profile of these children and studied the outcome in terms of their growth and renal failure. This is a retrospective longitudinal study of all children with renal tubular disorders attending a tertiary care pediatric nephrology center from 2005 to 2010. Growth and renal outcomes were assessed by Z scores and estimated glomerular filtration rate at diagnosis and. The common disorders encountered were distal renal tubular acidosis (d-RTA (44%, Bartter-like (Bartter′s and Gitelman syndromes (22% followed by hereditary Fanconi syndrome (cystinosis and idiopathic Fanconi syndrome (13% and few cases of nephrogenic diabetes insipidus, hypophosphatemic rickets and idiopathic hypercalciuria. Male: female ratio was 1.22. The median age at diagnosis was 1.5 (range 0.13-11 years. Growth failure was the presenting feature in 86% of children followed by polyuria (60% and bone deformities (47%. In 60% of children with hereditary Fanconi syndrome, nephropathic cystinosis was diagnosed, all of whom progressed to stage III chronic kidney disease (CKD within 3.41 ± 1.42 years. With appropriate therapy, catch-up growth was noted in d-RTA and Bartter syndrome. Renal tubular disorders usually present with FTT. d-RTA is the most common etiology followed by Bartter-like syndrome. Renal function is preserved in all these disorders except for nephropathic cystinosis, who ultimately progressed to CKD. With appropriate and inexpensive therapy, these children do grow well.

  15. Distal renal tubular acidosis and hypokalemic paralysis in a patient with hypothyroidism

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    Parvaiz Ahmad Koul

    2011-01-01

    Full Text Available A 43- year- old woman on treatment for primary hypothyroidism presented with 1- day progressive weakness of all her limbs and history of similar episodes in the past. Clinical examination revealed grade 2 hyporeflexive weakness. Investigations revealed features of hypokalemia, metabolic acidosis, alkaline urine, and a fractional bicarbonate excretion of 3.5%, consistent with distal renal tubular acidosis. Antithyroid peroxidase and antithroglobulin antibodies were positive, suggesting an autoimmune basis for the pathogenesis of the functional tubular defect. Bicarbonate therapy resulted in a sustained clinical recovery.

  16. Overendocytosis of gold nanoparticles increases autophagy and apoptosis in hypoxic human renal proximal tubular cells

    Directory of Open Access Journals (Sweden)

    Ding F

    2014-09-01

    Full Text Available Fengan Ding,1 Yiping Li,1 Jing Liu,1 Lei Liu,1 Wenmin Yu,1 Zhi Wang,1 Haifeng Ni,2 Bicheng Liu,2 Pingsheng Chen1,2 1School of Medicine, Southeast University, Nanjing, People’s Republic of China; 2Institute of Nephrology, The Affiliated Zhongda Hospital, Southeast University, Nanjing, People’s Republic of China Background: Gold nanoparticles (GNPs can potentially be used in biomedical fields ranging from therapeutics to diagnostics, and their use will result in increased human exposure. Many studies have demonstrated that GNPs can be deposited in the kidneys, particularly in renal tubular epithelial cells. Chronic hypoxic is inevitable in chronic kidney diseases, and it results in renal tubular epithelial cells that are susceptible to different types of injuries. However, the understanding of the interactions between GNPs and hypoxic renal tubular epithelial cells is still rudimentary. In the present study, we characterized the cytotoxic effects of GNPs in hypoxic renal tubular epithelial cells.Results: Both 5 nm and 13 nm GNPs were synthesized and characterized using various biophysical methods, including transmission electron microscopy, dynamic light scattering, and ultraviolet–visible spectrophotometry. We detected the cytotoxicity of 5 and 13 nm GNPs (0, 1, 25, and 50 nM to human renal proximal tubular cells (HK-2 by Cell Counting Kit-8 assay and lactate dehydrogenase release assay, but we just found the toxic effect in the 5 nm GNP-treated cells at 50 nM dose under hypoxic condition. Furthermore, the transmission electron microscopy images revealed that GNPs were either localized in vesicles or free in the lysosomes in 5 nm GNPs-treated HK-2 cells, and the cellular uptake of the GNPs in the hypoxic cells was significantly higher than that in normoxic cells. In normoxic HK-2 cells, 5 nm GNPs (50 nM treatment could cause autophagy and cell survival. However, in hypoxic conditions, the GNP exposure at the same condition led to the

  17. Renal tubular acidosis secondary to jejunoileal bypass for morbid obesity

    DEFF Research Database (Denmark)

    Schaffalitzky de Muckadell, O B; Ladefoged, Jens; Thorup, Jørgen Mogens

    1985-01-01

    Renal handling of acid and base was studied in patients with persistent metabolic acidosis 3-9 years after jejunoileal bypass for morbid obesity. Excretion of acid was studied before and after intravenous infusion of NH4Cl and excretion of bicarbonate after infusion of NaHCO3. Bypass patients...

  18. Effect of benazepril on the transdifferentiation of renal tubular epithelial cells from diabetic rats.

    Science.gov (United States)

    Peng, Tao; Wang, Jie; Zhen, Junhui; Hu, Zhao; Yang, Xiangdong

    2014-07-01

    The aim of this study was to investigate the effect of benazepril on the transdifferentiation of renal tubular epithelial cells from diabetic rats. Thirty male Sprague-Dawley rats were included in the present study. Eight of the 30 rats were randomly selected and served as the normal control group (N group), while the remaining 22 rats, injected with streptozotocin (STZ), comprised the diabetic rat model. Rats with diabetes were randomly divided into the diabetic (DM group) and benazepril (B group) groups. The total course was conducted over 12 weeks. Blood glucose, body weight, kidney/body weight, 24-h urinary protein, serum creatinine and blood urea nitrogen were measured at the start and end of the study. We observed the tubulointerstitial pathological changes, and applied immunohistochemistry and western blotting to detect the expression of α-smooth muscle actin (α-SMA) in renal tissue. The levels of blood glucose, kidney/body weight, 24-h urinary protein, serum creatinine, blood urea nitrogen and tubulointerstitial damage index (TII) in the DM group were significantly higher than that in the N group (pbenazepril significantly reduced the expression of α-SMA in renal tubular epithelial cells obtained from diabetic rats, inhibited the transdifferentiation of renal tubular epithelial cells and played an important role in kidney protection.

  19. Dual energy CT monitoring of the renal corticomedullary sodium gradient in swine

    International Nuclear Information System (INIS)

    Kumar, Rahi; Wang, Zhen J.; Forsythe, Carlos; Fu Yanjun; Chen, Yunn-Yi; Yeh, Benjamin M.

    2012-01-01

    Objective: To evaluate the feasibility of dual-energy CT (DECT) for monitoring dynamic changes in the renal corticomedullary sodium gradient in swine. Material and methods: This study was approved by our Institutional Animal Care and Use Committee. Four water-restricted pigs were CT-scanned at 80 and 140 kVp at baseline and at 5 min intervals for 30 min during saline or furosemide diuresis. The renal cortical and medullary CT numbers were recorded. A DECT basis material decomposition method was used to quantify renal cortical and medullary sodium concentrations and medulla-to-cortex sodium ratios at each time point based on the measured CT numbers. The sodium concentrations and medulla-to-cortex sodium ratios were compared between baseline and at 30 min diuresis using paired Student t-tests. The medulla-to-cortex sodium ratios were considered to reflect the corticomedullary sodium gradient. Results: At baseline prior to saline diuresis, the mean medullary and cortical sodium concentrations were 103.8 ± 8.7 and 65.3 ± 1.7 mmol/l, respectively, corresponding to a medulla-to-cortex sodium ratio of 1.59. At 30 min of saline diuresis, the medullary and cortical sodium concentrations decreased to 72.3 ± 1.0 and 56.0 ± 1.4 mmol/l, respectively, corresponding to a significantly reduced medulla-to-cortex sodium ratio of 1.29 (P < 0.05). At baseline prior to furosemide diuresis, the mean medullary and cortical sodium concentrations were 110.5 ± 3.6 and 66.7 ± 4.1 mmol/l, respectively, corresponding to a medulla-to-cortex sodium ratio of 1.66. At 30 min of furosemide diuresis, the medullary and cortical sodium concentrations decreased to 68.5 ± 0.3 and 58.9 ± 4.0 mmol/l, respectively, corresponding to a significantly reduced medulla-to-cortex sodium ratio of 1.16 (P < 0.05). One of the 4 pigs developed acute tubular necrosis likely related to prolonged hypoxia during intubation prior to the furosemide diuresis experiment. The medulla-to-cortex sodium ratio for this

  20. Interferon-γ Reduces the Proliferation of Primed Human Renal Tubular Cells

    Directory of Open Access Journals (Sweden)

    Omar García-Sánchez

    2014-01-01

    Full Text Available Background/Aims: Chronic kidney disease (CKD is a progressive deterioration of the kidney function, which may eventually lead to renal failure and the need for dialysis or kidney transplant. Whether initiated in the glomeruli or the tubuli, CKD is characterized by progressive nephron loss, for which the process of tubular deletion is of key importance. Tubular deletion results from tubular epithelial cell death and defective repair, leading to scarring of the renal parenchyma. Several cytokines and signaling pathways, including transforming growth factor-β (TGF-β and the Fas pathway, have been shown to participate in vivo in tubular cell death. However, there is some controversy about their mode of action, since a direct effect on normal tubular cells has not been demonstrated. We hypothesized that epithelial cells would require specific priming to become sensitive to TGF-β or Fas stimulation and that this priming would be brought about by specific mediators found in the pathological scenario. Methods: Herein we studied whether the combined effect of several stimuli known to take part in CKD progression, namely TGF-β, tumor necrosis factor-α, interferon-γ (IFN-γ, and Fas stimulation, on primed resistant human tubular cells caused cell death or reduced proliferation. Results: We demonstrate that these cytokines have no synergistic effect on the proliferation or viability of human kidney (HK2 cells. We also demonstrate that IFN-γ, but not the other stimuli, reduces the proliferation of cycloheximide-primed HK2 cells without affecting their viability. Conclusion: Our results point at a potentially important role of IFN-γ in defective repair, leading to nephron loss during CKD.

  1. Furosemide/Fludrocortisone Test and Clinical Parameters to Diagnose Incomplete Distal Renal Tubular Acidosis in Kidney Stone Formers.

    Science.gov (United States)

    Dhayat, Nasser A; Gradwell, Michael W; Pathare, Ganesh; Anderegg, Manuel; Schneider, Lisa; Luethi, David; Mattmann, Cedric; Moe, Orson W; Vogt, Bruno; Fuster, Daniel G

    2017-09-07

    Incomplete distal renal tubular acidosis is a well known cause of calcareous nephrolithiasis but the prevalence is unknown, mostly due to lack of accepted diagnostic tests and criteria. The ammonium chloride test is considered as gold standard for the diagnosis of incomplete distal renal tubular acidosis, but the furosemide/fludrocortisone test was recently proposed as an alternative. Because of the lack of rigorous comparative studies, the validity of the furosemide/fludrocortisone test in stone formers remains unknown. In addition, the performance of conventional, nonprovocative parameters in predicting incomplete distal renal tubular acidosis has not been studied. We conducted a prospective study in an unselected cohort of 170 stone formers that underwent sequential ammonium chloride and furosemide/fludrocortisone testing. Using the ammonium chloride test as gold standard, the prevalence of incomplete distal renal tubular acidosis was 8%. Sensitivity and specificity of the furosemide/fludrocortisone test were 77% and 85%, respectively, yielding a positive predictive value of 30% and a negative predictive value of 98%. Testing of several nonprovocative clinical parameters in the prediction of incomplete distal renal tubular acidosis revealed fasting morning urinary pH and plasma potassium as the most discriminative parameters. The combination of a fasting morning urinary threshold pH 3.8 mEq/L yielded a negative predictive value of 98% with a sensitivity of 85% and a specificity of 77% for the diagnosis of incomplete distal renal tubular acidosis. The furosemide/fludrocortisone test can be used for incomplete distal renal tubular acidosis screening in stone formers, but an abnormal furosemide/fludrocortisone test result needs confirmation by ammonium chloride testing. Our data furthermore indicate that incomplete distal renal tubular acidosis can reliably be excluded in stone formers by use of nonprovocative clinical parameters. Copyright © 2017 by the American

  2. Insuficiencia renal aguda con necrosis tubular aguda secundaria a picadura masiva de abejas

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    Gustavo A. Aroca - Martínez

    2006-01-01

    Full Text Available Leñador de 46 años consulta al servicio de nefrología, de la Clínica Renal de la Costa en Barranquilla, con episodio de insuficiencia renal aguda 48 horas después de haber sufrido múltiples picaduras por abejas africanizadas. Durante su estancia hospitalaria presentó incremento de enzimas musculares (AST LDH, y de pruebas de función renal, motivo por el cual fue dializado en varias ocasiones. Con mejoría total, se decide egresar y manejar ambulatoriamente. Se concluye que el caso se trata de una insuficiencia renal por necrosis tubular aguda por rabdomiolisis debida a la picadura múltiple de abejas africanizadas.

  3. Renal functional reserve and tubular function in patents with type 2 diabetes mellitus

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    Dilyara Makhmutrievna Khakimova

    2011-06-01

    Full Text Available Aim. To study renal functional reserve and partial functions in patents with type 2 diabetes mellitus in the absence of renal lesionsMaterials and methods. We examined 42 patients (17 men and 24 women aged 38-69 (mean 49.8?8.3 years with DM2 4.6?2.6 yr in duration.Control group comprised 32 practically healthy subjects. Intrarenal hemodynamics was estimated from RFR values. Ethanolamine, uric acid, Ca,and P levels were measured in sera and 24-hr urine; daily excretion of ammonia and aminonitrogen in the urine was determined. Results. The patients were divided into 2 groups based on the results of RFR measurement. FRF remained unaltered in 21 patients (mean 60.7?27.6%and decreased in the absence of filtration reserve in 20 (-25.8?23.4%. Correlation analysis revealed the relationship of lipid metabolism and abdominalobesity with the renal tubular function and intraglomerular hemodynamics. Conclusion. Examination of DM2 patients without clinical and laboratory signs of renal lesions revealed compromised function of all nephron compartments,viz. intraglomerular hypertension, impaired stability of renal cell membranes, and tubular dysfunction. The latter is related to hemodynamic disturbances.

  4. Regulatory mechanism of ulinastatin on autophagy of macrophages and renal tubular epithelial cells

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    Wu Ming

    2018-04-01

    Full Text Available Kidney ischemia and hypoxia can cause renal cell apoptosis and activation of inflammatory cells, which lead to the release of inflammatory factors and ultimately result in the damage of kidney tissue and the whole body. Renal tubular cell and macrophage autophagy can reduce the production of reactive oxygen species (ROS, thereby reducing the activation of inflammatory cytoplasm and its key effector protein, caspase-1, which reduces the expression of IL-1β and IL-18 and other inflammatory factors. Ulinastatin (UTI, as a glycoprotein drug, inhibits the activity of multiple proteases and reduces myocardial damage caused by ischemia-reperfusion by upregulating autophagy. However, it can be raised by macrophage autophagy, reduce the production of ROS, and ultimately reduce the expression of inflammatory mediators, thereby reducing renal cell injury, promote renal function recovery is not clear. In this study, a series of cell experiments have shown that ulinastatin is reduced by regulating the autophagy of renal tubular epithelial cells and macrophages to reduce the production of reactive oxygen species and inflammatory factors (TNF-α, IL-1β and IL-1, and then, increase the activity of the cells under the sugar oxygen deprivation model. The simultaneous use of cellular autophagy agonists Rapamycin (RAPA and ulinastatin has a synergistic effect on the production of reactive oxygen species and the expression of inflammatory factors.

  5. Usefulness of zebrafish larvae to evaluate drug-induced functional and morphological renal tubular alterations.

    Science.gov (United States)

    Gorgulho, Rita; Jacinto, Raquel; Lopes, Susana S; Pereira, Sofia A; Tranfield, Erin M; Martins, Gabriel G; Gualda, Emilio J; Derks, Rico J E; Correia, Ana C; Steenvoorden, Evelyne; Pintado, Petra; Mayboroda, Oleg A; Monteiro, Emilia C; Morello, Judit

    2018-01-01

    Prediction and management of drug-induced renal injury (DIRI) rely on the knowledge of the mechanisms of drug insult and on the availability of appropriate animal models to explore it. Zebrafish (Danio rerio) offers unique advantages for assessing DIRI because the larval pronephric kidney has a high homology with its human counterpart and it is fully mature at 3.5 days post-fertilization. Herein, we aimed to evaluate the usefulness of zebrafish larvae as a model of renal tubular toxicity through a comprehensive analysis of the renal alterations induced by the lethal concentrations for 10% of the larvae for gentamicin, paracetamol and tenofovir. We evaluated drug metabolic profile by mass spectrometry, renal function with the inulin clearance assay, the 3D morphology of the proximal convoluted tubule by two-photon microscopy and the ultrastructure of proximal convoluted tubule mitochondria by transmission electron microscopy. Paracetamol was metabolized by conjugation and oxidation with further detoxification with glutathione. Renal clearance was reduced with gentamicin and paracetamol. Proximal tubules were enlarged with paracetamol and tenofovir. All drugs induced mitochondrial alterations including dysmorphic shapes ("donuts", "pancakes" and "rods"), mitochondrial swelling, cristae disruption and/or loss of matrix granules. These results are in agreement with the tubular effects of gentamicin, paracetamol and tenofovir in man and demonstrate that zebrafish larvae might be a good model to assess functional and structural damage associated with DIRI.

  6. Exosome production and its regulation of EGFR during wound healing in renal tubular cells.

    Science.gov (United States)

    Zhou, Xiangjun; Zhang, Wei; Yao, Qisheng; Zhang, Hao; Dong, Guie; Zhang, Ming; Liu, Yutao; Chen, Jian-Kang; Dong, Zheng

    2017-06-01

    Kidney repair following injury involves the reconstitution of a structurally and functionally intact tubular epithelium. Growth factors and their receptors, such as EGFR, are important in the repair of renal tubules. Exosomes are cell-produced small (~100 nm in diameter) vesicles that contain and transfer proteins, lipids, RNAs, and DNAs between cells. In this study, we examined the relationship between exosome production and EGFR activation and the potential role of exosome in wound healing. EGFR activation occurred shortly after scratch wounding in renal tubular cells. Wound repair after scratching was significantly promoted by EGF and suppressed by EGFR inhibitor gefitinib. Interestingly, scratch wounding induced a significant increase of exosome production. The exosome production was decreased by EGF and increased by gefitinib, suggesting a suppressive role of EGFR signaling in exosome production. Conversely, inhibition of exosome release by GW4869 and manumycin A markedly increased EGFR activation and promoted wound healing. Moreover, exosomes derived from scratch-wounding cells could inhibit wound healing. Collectively, the results indicate that wound healing in renal tubular cells is associated with EGFR activation and exosome production. Although EGFR activation promotes wound healing, released exosomes may antagonize EGFR activation and wound healing. Copyright © 2017 the American Physiological Society.

  7. High Glucose Increases Metallothionein Expression in Renal Proximal Tubular Epithelial Cells

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    Daisuke Ogawa

    2011-01-01

    Full Text Available Metallothionein (MT is an intracellular metal-binding, cysteine-rich protein, and is a potent antioxidant that protects cells and tissues from oxidative stress. Although the major isoforms MT-1 and -2 (MT-1/-2 are highly inducible in many tissues, the distribution and role of MT-1/-2 in diabetic nephropathy are poorly understood. In this study, diabetes was induced in adult male rats by streptozotocin, and renal tissues were stained with antibodies for MT-1/-2. MT-1/-2 expression was also evaluated in mProx24 cells, a mouse renal proximal tubular epithelial cell line, stimulated with high glucose medium and pretreated with the antioxidant vitamin E. MT-1/-2 expression was gradually and dramatically increased, mainly in the proximal tubular epithelial cells and to a lesser extent in the podocytes in diabetic rats, but was hardly observed in control rats. MT-1/-2 expression was also increased by high glucose stimulation in mProx24 cells. Because the induction of MT was suppressed by pretreatment with vitamin E, the expression of MT-1/-2 is induced, at least in part, by high glucose-induced oxidative stress. These observations suggest that MT-1/-2 is induced in renal proximal tubular epithelial cells as an antioxidant to protect the kidney from oxidative stress, and may offer a novel therapeutic target against diabetic nephropathy.

  8. Tubular and endothelial chimerism in renal allografts using fluorescence and chromogenic in situ hybridization (FISH, CISH) technology.

    Science.gov (United States)

    Varga, Zsuzsanna; Gaspert, Ariana; Behnke, Silvia; von Teichman, Adriana; Fritzsche, Florian; Fehr, Thomas

    2012-04-01

    The role of endothelial and tubular chimerism in renal allograft adaptation and rejection varies in different studies. We addressed the correlation between different clinico-pathological settings and sex-chromosomal endothelial and/or tubular chimerism in renal allografts. We examined the presence or absence of the X and Y chromosomes by fluorescence and chromogenic in situ hybridization (FISH, CISH) methodology on paraffin embedded kidney biopsies in 16 gender mismatched renal transplants (1 to 12 years post-transplantation). Twelve patients were male, four female. Four groups were selected: (i) Vascular calcineurin inhibitor toxicity without rejection; (ii) T-cell mediated vascular rejection; (iii) antibody mediated rejection; and (iv) C4d-positivity in AB0-incompatible transplants with or without rejection. Twelve non-transplant kidney biopsies (8 female, 4 male) were used as controls. Tubular chimerism was detected more frequently (69%) than endothelial chimerism (12%) in renal transplants. One of 12 control patients had tubular and endothelial chimeric cells (8%). The Y chromosome occurred in 8/12 male recipients (67%) in tubular epithelial cells and in 5/12 male recipients (42%) in endothelial cells. Double X chromosomes were detected in 3/4 female recipients in tubular epithelium. Tubular chimerism occurred more often with endothelial chimerism and capillaritis without correlation with other parameters, such as rejection. Combined Y chromosomal tubular and lymphatic endothelial chimerism correlated with T-cell mediated vascular rejection in two out of three patients (66%). Combined Y chromosomal tubular and peritubular capillary chimerism correlated with antibody mediated C4d+ rejection in one out of two patients (50%). Tubular and/or endothelial chimerism occur frequently in gender mismatched renal allografts and, when combined, this is associated with T-cell mediated rejection. © 2012 The Authors. Pathology International © 2012 Japanese Society of

  9. [Case of distal renal tubular acidosis complicated with renal diabetes insipidus, showing aggravation of symptoms with occurrence of diabetes mellitus].

    Science.gov (United States)

    Liu, Hexing; Tomoda, Fumihiro; Koike, Tsutomu; Ohara, Maiko; Nakagawa, Taizo; Kagitani, Satoshi; Inoue, Hiroshi

    2011-01-01

    We report herein a 27-year-old male case of inherited distal renal tubular acidosis complicated with renal diabetes insipidus, the symptoms of which were aggravated by the occurrence of diabetes mellitus. At 2 months after birth, he was diagnosed as having inherited distal renal tubular acidosis and thereafter supplementation of both potassium and alkali was started to treat his hypokalemia and metabolic acidosis. At the age of 4 years, calcification of the bilateral renal medulla was detected by computed tomography. Subsequently his urinary volume gradually increased and polyuria of approximately 4 L/day persisted. At the age of 27 years, he became fond of sugar-sweetened drinks and also often forgot to take the medicine. He was admitted to our hospital due to polyuria of more than 10 L day, muscle weakness and gait disturbance. Laboratory tests disclosed worsening of both hypokalemia and metabolic acidosis in addition to severe hyperglycemia. It seemed likely that occurrence of diabetes mellitus and cessation of medications can induce osmotic diuresis and aggravate hypokalemia and metabolic acidosis. Consequently, severe dehydration, hypokalemia-induced damage of his urinary concentration ability and enhancement of the renin angiotensin system occurred and thereby possibly worsened his hypokalemia and metabolic acidosis. As normalization of hyperglycemia and metabolic acidosis might have exacerbated hypokalemia further, dehydration and hypokalemia were treated first. Following intensive treatment, these abnormalities were improved, but polyuria persisted. Elevated plasma antidiuretic hormone (12.0 pg/mL) and deficit of renal responses to antidiuretic hormone suggested that the polyuria was attributable to the preexisting renal diabetes insipidus possibly caused by bilateral renal medulla calcification. Thiazide diuretic or nonsteroidal anti-inflammatory drugs were not effective for the treatment of diabetes insipidus in the present case.

  10. Urinary Beta-2Microglobulin: An Indicator of Renal Tubular Damage after Extracorporeal Shock Wave Lithotripsy.

    Science.gov (United States)

    Nasseh, Hamidreza; Abdi, Sepideh; Roshani, Ali; Kazemnezhad, Ehsan

    2016-12-08

    This study aims to determine extracorporeal shock wave lithotripsy (ESWL)-induced renal tubular damageand the affecting factors by measuring urinary beta2microglobulin (β2M) excretion. This is a cross-sectional study conducted on 91 patients with renal stones who underwentESWL during 2012. Urinary beta2microglobulin was measured immediately before and after the procedure foreach patient and analyzed based on different variables to evaluate factors affecting ESWL-induced renal tubularinjury. Mean ± SD urinary beta2-microglobulin values, before and after ESWL were 0.08 ± 0.07 and 0.22 ± 0.71mg/dL respectively, the average difference between which was equal to 0.14 ± 0.07 mg/dL. These figures exhibiteda 166.66% rise in the urinary β2M concentration after ESWL which was statistically significant (P ESWL (P = .02) were predictive factors ofhigher post-ESWL urinary beta2-microglobulin excretion. Urinary excretion of beta2-microglobulin increased significantly immediately after ESWL. Thesechanges could indicate that ESWL is a contributing factor to renal tubular damage. It also seems that in patientswith hypertension and a previous history of ESWL the likelihood of this injury is higher than others.

  11. Effects of compound Shenhua tablet on renal tubular Na+-K+-ATPase in rats with acute ischemic reperfusion injury.

    Science.gov (United States)

    Yang, Yue; Wei, Ri-bao; Zheng, Xiao-yong; Qiu, Qiang; Cui, Shao-yuan; Yin, Zhong; Shi, Suo-zhu; Chen, Xiang-mei

    2014-03-01

    To observe the effect of Compound Shenhua Tablet (, SHT) on the sodium-potassium- exchanging adenosinetriphosphatase (Na(+)-K(+)-ATPase) in the renal tubular epithelial cells of rats with acute ischemic reperfusion and to investigate the mechanisms underlying the effects of SHT on renal ischemic reperfusion injury (RIRI). Fifty male Wistar rats were randomly divided into the sham surgery group, model group, astragaloside group [150 mg/(kg·d)], SHT low-dose group [1.5 g/(kg·d)] and SHT high-dose group [3.0 g/(kg·d)], with 10 rats in each group. After 1 week of continuous intragastric drug administration, surgery was performed to establish the model. At either 24 or 72 h after the surgery, 5 rats in each group were sacrificed, blood biochemistry, renal pathology, immunoblot and immunohistochemical examinations were performed, and double immunofluorescence staining was observed under a laser confocal microscope. Compared with the sham surgery group, the serum creatinine (SCr) and blood urea nitrogen (BUN) levels were significantly increased, Na(+)-K(+)-ATPase protein level was decreased, and kidney injury molecule-1 (KIM-1) protein level was increased in the model group after the surgery (P<0.01 or P<0.05). Compared with the model group, the SCr, BUN, pathological scores, Na(+)-K(+)-ATPase, and the KIM-1 protein level of the three treatment groups were significantly improved at 72 h after the surgery (P<0.05 or P<0.01). And the SCr, BUN of the SHT low- and high-dose groups, and the pathological scores of the SHT high-dose group were significantly lower than those of the astragaloside group (P<0.05). The localizations of Na(+)-K(+)-ATPase and megalin of the model group were disrupted, with the distribution areas overlapping with each other and alternately arranged. The severity of the disruption was slightly milder in three treatment groups compared with that of the model group. The results of immunofluorescence staining showed that the SHT high-dose group had a

  12. Renal blood flow after transplantation: Effects of acute tubular necrosis, rejection, and cyclosporine toxicity

    International Nuclear Information System (INIS)

    Lear, J.L.; Raff, U.; Jain, R.; Horgan, J.G.

    1988-01-01

    The authors incorporated their recently developed radionuclide first pass-technique for the quantitative measurement of renal transplant perfusion into routine DTPA imaging. Using this technique they investigated the effects of acute tubular necrosis (ATN), rejection, and cyclosporing toxicity on renal blood flow in a series of 80 studies in 35 patients, with independent evaluation of renal function. Transplant flow values were as follows: normal functioning, 439 mL/min +-83; ATN 248 mL/min +-63; rejection, 128 mL/min +-58; cyclosporing toxicity, 284 mL/min +-97; (normal flow in nontransplanted kidneys, approximately 550 mL/min). Differences between normal functioning, ATN, and rejection were significant (P < .05). Interestingly, immediate postsurgical hyperemia frequently occurred, with flow values sometimes exceeding 700 mL/min

  13. Hyperglycemia induced damage to mitochondrial respiration in renal mesangial and tubular cells: Implications for diabetic nephropathy

    Directory of Open Access Journals (Sweden)

    Anna Czajka

    2016-12-01

    Full Text Available Damage to renal tubular and mesangial cells is central to the development of diabetic nephropathy (DN, a complication of diabetes which can lead to renal failure. Mitochondria are the site of cellular respiration and produce energy in the form of ATP via oxidative phosphorylation, and mitochondrial dysfunction has been implicated in DN. Since the kidney is an organ with high bioenergetic needs, we postulated that hyperglycemia causes damage to renal mitochondria resulting in bioenergetic deficit. The bioenergetic profiles and the effect of hyperglycemia on cellular respiration of human primary mesangial (HMCs and proximal tubular cells (HK-2 were compared in normoglycemic and hyperglycemic conditions using the seahorse bio-analyzer. In normoglycemia, HK-2 had significantly lower basal, ATP-linked and maximal respiration rates, and lower reserve capacity compared to HMCs. Hyperglycemia caused a down-regulation of all respiratory parameters within 4 days in HK-2 but not in HMCs. After 8 days of hyperglycemia, down-regulation of respiratory parameters persisted in tubular cells with compensatory up-regulated glycolysis. HMCs had reduced maximal respiration and reserve capacity at 8 days, and by 12 days had compromised mitochondrial respiration despite which they did not enhance glycolysis. These data suggest that diabetes is likely to lead to a cellular deficit in ATP production in both cell types, although with different sensitivities, and this mechanism could significantly contribute to the cellular damage seen in the diabetic kidney. Prevention of diabetes induced damage to renal mitochondrial respiration may be a novel therapeutic approach for the prevention/treatment of DN.

  14. Involvement of caspase-12-dependent apoptotic pathway in ionic radiocontrast urografin-induced renal tubular cell injury

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Cheng Tien [Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Weng, Te I. [Department of Forensic Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Chen, Li Ping [Department of Dentistry, Chang Gang Memorial Hospital, Chang Gang University, Taoyuan, Taiwan (China); Chiang, Chih Kang [Department of Integrated Diagnostics and Therapeutics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China); Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China); Liu, Shing Hwa, E-mail: shinghwaliu@ntu.edu.tw [Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China)

    2013-01-01

    Contrast medium (CM) induces a direct toxic effect on renal tubular cells. This toxic effect subjects in the disorder of CM-induced nephropathy. Our previous work has demonstrated that CM shows to activate the endoplasmic reticulum (ER)-related adaptive unfolding protein response (UPR) activators. Glucose-regulated protein 78 (GRP78)/eukaryotic initiation factor 2α (eIF2α)-related pathways play a protective role during the urografin (an ionic CM)-induced renal tubular injury. However, the involvement of ER stress-related apoptotic signals in the urografin-induced renal tubular cell injury remains unclear. Here, we examined by the in vivo and in vitro experiments to explore whether ER stress-regulated pro-apoptotic activators participate in urografin-induced renal injury. Urografin induced renal tubular dilation, tubular cells detachment, and necrosis in the kidneys of rats. The tubular apoptosis, ER stress-related pro-apoptotic transcriptional factors, and kidney injury marker-1 (kim-1) were also conspicuously up-regulated in urografin-treated rats. Furthermore, treatment of normal rat kidney (NRK)-52E tubular cells with urografin augmented the expressions of activating transcription factor-6 (ATF-6), C/EBP homologous protein (CHOP), Bax, caspase-12, JNK, and inositol-requiring enzyme (IRE) 1 signals. Urografin-induced renal tubular cell apoptosis was not reversed by the inhibitors of ATF-6, JNK signals or CHOP siRNA transfection, but it could be partially reversed by the inhibitor of caspase-12. Taken together, the present results and our previous findings suggest that exposure of CM/urografin activates the ER stress-regulated survival- and apoptosis-related signaling pathways in renal tubular cells. Caspase-12-dependent apoptotic pathway may be partially involved in the urografin-induced nephropathy. -- Highlights: ► Ionic contrast medium-urografin induces renal tubular cell apoptosis. ► Urografin induces the ER stress-regulated survival and apoptosis

  15. Proximal renal tubular injury in rats sub-chronically exposed to low fluoride concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Cárdenas-González, Mariana C.; Del Razo, Luz M. [Departmento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), México, D. F., México (Mexico); Barrera-Chimal, Jonatan [Unidad de Fisiología Molecular, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México, D. F., México (Mexico); Jacobo-Estrada, Tania [Departmento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), México, D. F., México (Mexico); López-Bayghen, Esther [Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), México, D. F., México (Mexico); and others

    2013-11-01

    Fluoride is usually found in groundwater at a very wide range of concentration between 0.5 and 25 ppm. At present, few studies have assessed the renal effects of fluoride at environmentally relevant concentrations. Furthermore, most of these studies have used insensitive and nonspecific biomarkers of kidney injury. The aim of this study was to use early and sensitive biomarkers to evaluate kidney injury after fluoride exposure to environmentally relevant concentrations. Recently weaned male Wistar rats were exposed to low (15 ppm) and high (50 ppm) fluoride concentrations in drinking water for a period of 40 days. At the end of the exposure period, kidney injury biomarkers were measured in urine and renal mRNA expression levels were assessed by real time RT-PCR. Our results showed that the urinary kidney injury molecule (Kim-1), clusterin (Clu), osteopontin (OPN) and heat shock protein 72 excretion rate significantly increased in the group exposed to the high fluoride concentration. Accordingly, fluoride exposure increased renal Kim-1, Clu and OPN mRNA expression levels. Moreover, there was a significant dose-dependent increase in urinary β-2-microglobulin and cystatin-C excretion rate. Additionally, a tendency towards a dose dependent increase of tubular damage in the histopathological light microscopy findings confirmed the preferential impact of fluoride on the tubular structure. All of these changes occurred at early stages in which, the renal function was not altered. In conclusion using early and sensitive biomarkers of kidney injury, we were able to found proximal tubular alterations in rats sub-chronically exposed to fluoride. - Highlights: • Exposure to low concentrations of fluoride induced proximal tubular injury • Increase in urinary Kim-1, Clu, OPN and Hsp72 in 50 ppm fluoride-exposed group • Increase in urinary B2M and CysC in 15 and 50 ppm fluoride-exposed groups • Fluoride exposure increased renal Kim, Clu and OPN mRNA expression levels.

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

    Science.gov (United States)

    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.

  17. Reversal of Proximal Renal Tubular Dysfunction after Nucleotide Analogue Withdrawal in Chronic Hepatitis B

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    Abhasnee Sobhonslidsuk

    2017-01-01

    Full Text Available Aims. Proximal renal tubular dysfunction (PRTD is an infrequent complication after nucleotide analogue therapy. We evaluated the outcomes of PRTD and nephrotoxicity after nucleotide analogue withdrawal in chronic hepatitis B (CHB. Methods. A longitudinal follow-up study was performed in patients with PRTD after nucleotide analogue discontinuation. Serum and urine were collected at baseline and every 3 months for one year. The fractional excretion of phosphate (PO4, uric acid (UA, and potassium and tubular maximal reabsorption rate of PO4 to glomerular filtration rate (TmPO4/GFR were calculated. Renal losses were defined based on the criteria of substance losses. Subclinical PRTD and overt PRTD were diagnosed when 2 and ≥3 criteria were identified. Results. Eight subclinical and eight overt PRTD patients were enrolled. After nucleotide analogue withdrawal, there were overall improvements in GFR, serum PO4, and UA. Renal loss of PO4, UA, protein, and β2-microglobulin reduced over time. At one year, complete reversal of PRTD was seen in 13 patients (81.2%. Improvements in PRTD were seen in all but one patient. Conclusion. One year after nucleotide analogue withdrawal, PRTD was resolved in most patients. Changes in TmPO4/GFR, urinary protein, and β2-microglobulin indicate that urinary biomarkers may represent an early sign of PRTD recovery.

  18. Pediatric Sjogren syndrome with distal renal tubular acidosis and autoimmune hypothyroidism: an uncommon association.

    Science.gov (United States)

    Agarwal, Amit; Kumar, Pradeep; Gupta, Nomeeta

    2015-11-01

    A 14-year-old female came with the history of sudden onset weakness; during work up, she was found to have hyperchloremic metabolic acidosis with normal anion gap and normal renal function suggesting the possibility of renal tubular acidosis (RTA). On further evaluation of RTA, she had positive antinuclear antibody, anti-Ro, and anti-La antibodies. On nuclear scan of salivary glands, her left parotid gland was nonfunctional. Her parotid biopsy revealed dilated interlobular ducts engulfed by lymphoid cells. She also had autoimmune hypothyroidism as suggested by raised TSH and positive anti-TPO antibodies. At admission, her serum potassium levels were low and she was treated with intravenous potassium chloride. After she recovered from acute hypokalemic paralysis, she was started on oral potassium citrate along with phosphate supplements, hydroxychloroquine, oral prednisolone and thyroxine supplements. Over the next 6 months, she has significant reduction in the dosage of potassium, bicarbonate and phosphate and gained 3 kg of weight and 3.5 cm of height. As primary Sjogren syndrome itself is rare in pediatric population and its association with renal tubular acidosis is even rarer, we suggest considering Sjogren syndrome as a differential diagnosis during the RTA work-up is worth trying.

  19. Effect of taurine on advanced glycation end products-induced hypertrophy in renal tubular epithelial cells

    International Nuclear Information System (INIS)

    Huang, J.-S.; Chuang, L.-Y.; Guh, J.-Y.; Yang, Y.-L.; Hsu, M.-S.

    2008-01-01

    Mounting evidence indicates that advanced glycation end products (AGE) play a major role in the development of diabetic nephropathy (DN). Taurine is a well documented antioxidant agent. To explore whether taurine was linked to altered AGE-mediated renal tubulointerstitial fibrosis in DN, we examined the molecular mechanisms of taurine responsible for inhibition of AGE-induced hypertrophy in renal tubular epithelial cells. We found that AGE (but not non-glycated BSA) caused inhibition of cellular mitogenesis rather than cell death by either necrosis or apoptosis. There were no changes in caspase 3 activity, bcl-2 protein expression, and mitochondrial cytochrome c release in BSA, AGE, or the antioxidant taurine treatments in these cells. AGE-induced the Raf-1/extracellular signal-regulated kinase (ERK) activation was markedly blocked by taurine. Furthermore, taurine, the Raf-1 kinase inhibitor GW5074, and the ERK kinase inhibitor PD98059 may have the ability to induce cellular proliferation and cell cycle progression from AGE-treated cells. The ability of taurine, GW5074, or PD98059 to inhibit AGE-induced hypertrophy was verified by the observation that it significantly decreased cell size, cellular hypertrophy index, and protein levels of RAGE, p27 Kip1 , collagen IV, and fibronectin. The results obtained in this study suggest that taurine may serve as the potential anti-fibrotic activity in DN through mechanism dependent of its Raf-1/ERK inactivation in AGE-induced hypertrophy in renal tubular epithelial cells

  20. Renal handling of technetium-99m DMSA in rats with proximal tubular dysfunction

    International Nuclear Information System (INIS)

    Provoost, A.P.; Van Aken, M.

    1985-01-01

    The renal handling of technetium-/sup 99m/ dimercaptosuccinic acid ([/sup 99m/Tc]DMSA) was studied in rats before and after treatment with Na-maleate (2 mmol/kg i.v.). In the control period, when measured 2 hr after the intravenous injection of [/sup 99m/Tc]DMSA, 39.9% of the injected dose was in the kidneys and 14.6% was in the bladder. After Na-maleate treatment, only 6.4% of the injected dose of [/sup 99m/Tc]DMSA was retained in the kidneys while 37.9% was found in the bladder. Subsequent studies revealed that Na-maleate produced a fall in the glomerular filtration rate, the effective renal plasma flow, and a generalized proximal tubular dysfunction. The latter was characterized by polyuria and an increased excretion of glucose, protein, albumin, calcium, and inorganic phosphate. It was concluded that proximal tubular dysfunction markedly alters the renal handling of [/sup 99m/Tc]DMSA. Whether this augmented urinary excretion is due to an inhibition of reabsorption or an enhanced cellular efflux of [/sup 99m/Tc]DMSA remains to be answered

  1. ER stress and basement membrane defects combine to cause glomerular and tubular renal disease resulting from Col4a1 mutations in mice

    Directory of Open Access Journals (Sweden)

    Frances E. Jones

    2016-02-01

    Full Text Available Collagen IV is a major component of basement membranes, and mutations in COL4A1, which encodes collagen IV alpha chain 1, cause a multisystemic disease encompassing cerebrovascular, eye and kidney defects. However, COL4A1 renal disease remains poorly characterized and its pathomolecular mechanisms are unknown. We show that Col4a1 mutations in mice cause hypotension and renal disease, including proteinuria and defects in Bowman's capsule and the glomerular basement membrane, indicating a role for Col4a1 in glomerular filtration. Impaired sodium reabsorption in the loop of Henle and distal nephron despite elevated aldosterone levels indicates that tubular defects contribute to the hypotension, highlighting a novel role for the basement membrane in vascular homeostasis by modulation of the tubular response to aldosterone. Col4a1 mutations also cause diabetes insipidus, whereby the tubular defects lead to polyuria associated with medullary atrophy and a subsequent reduction in the ability to upregulate aquaporin 2 and concentrate urine. Moreover, haematuria, haemorrhage and vascular basement membrane defects confirm an important vascular component. Interestingly, although structural and compositional basement membrane defects occurred in the glomerulus and Bowman's capsule, no tubular basement membrane defects were detected. By contrast, medullary atrophy was associated with chronic ER stress, providing evidence for cell-type-dependent molecular mechanisms of Col4a1 mutations. These data show that both basement membrane defects and ER stress contribute to Col4a1 renal disease, which has important implications for the development of treatment strategies for collagenopathies.

  2. Lipid myopathy associated with renal tubular acidosis and spastic diplegia in two brothers.

    Science.gov (United States)

    Tung, Y C; Tsau, Y K; Chu, L W; Young, C; Shen, Y Z

    2001-07-01

    Lipid myopathy is a group of disorders involving mitochondrial fatty acid oxidation. We describe two brothers, 3 years 8 months old and 2 years 9 months old, respectively, with progressive spastic diplegia, developmental delay, failure to thrive, and chronic metabolic acidosis who had lipid myopathy and renal tubular acidosis. Brain magnetic resonance imaging revealed demyelinating changes in the periventricular white matter, which was compatible with spastic diplegia. These symptoms may be related to errors in fatty acid metabolism. Cerebral palsy had been misdiagnosed in both of these patients at another hospital. Therefore, for patients with late-onset and progressive spastic diplegia, detailed investigations for underlying diseases are warranted.

  3. Evaluation of (o)-[77Br]bromohippuran as renal tubular function agent

    International Nuclear Information System (INIS)

    Aswegen, A. van; Roodt, J.P.; Pieters, H.; Herbst, C.P.; Otto, A.C.; Loetter, M.G.; Minnaar, P.C.; Haasbroek, F.J.

    1985-01-01

    (o)-[ 77 Br]bromohippuran (BHIP) was developed as renal tubular function agent due to its favourable chemical and physical properties and compared to (o)-[ 131 I]iodohippuran (IHIP). Renograms obtained from baboons were compared and absorbed radiation dose calculations performed. Although BHIP showed a delayed kidney uptake and washout pattern, good kidney clearance of the radionuclide was obtained after 30 min. Radiation dose values for BHIP were markedly lower than for IHIP indicating that larger activities of BHIP could be administered to increase counting statistics. BHIP imaging in normal volunteers did however not substantiate the favourable behaviour obtained in the primate. (author)

  4. Comparison of four decontamination treatments on porcine renal decellularized extracellular matrix structure, composition, and support of human renal cortical tubular epithelium cells.

    Science.gov (United States)

    Poornejad, Nafiseh; Nielsen, Jeffery J; Morris, Ryan J; Gassman, Jason R; Reynolds, Paul R; Roeder, Beverly L; Cook, Alonzo D

    2016-03-01

    Engineering whole organs from porcine decellularized extracellular matrix and human cells may lead to a plentiful source of implantable organs. Decontaminating the porcine decellularized extracellular matrix scaffolds is an essential step prior to introducing human cells. However, decontamination of whole porcine kidneys is a major challenge because the decontamination agent or irradiation needs to diffuse deep into the structure to eliminate all microbial contamination while minimizing damage to the structure and composition of the decellularized extracellular matrix. In this study, we compared four decontamination treatments that could be applicable to whole porcine kidneys: 70% ethanol, 0.2% peracetic acid in 1 M NaCl, 0.2% peracetic acid in 4% ethanol, and gamma (γ)-irradiation. Porcine kidneys were decellularized by perfusion of 0.5% (w/v) aqueous solution of sodium dodecyl sulfate and the four decontamination treatments were optimized using segments (n = 60) of renal tissue to ensure a consistent comparison. Although all four methods were successful in decontamination, γ-irradiation was very damaging to collagen fibers and glycosaminoglycans, leading to less proliferation of human renal cortical tubular epithelium cells within the porcine decellularized extracellular matrix. The effectiveness of the other three optimized solution treatments were then all confirmed using whole decellularized porcine kidneys (n = 3). An aqueous solution of 0.2% peracetic acid in 1 M NaCl was determined to be the best method for decontamination of porcine decellularized extracellular matrix. © The Author(s) 2015.

  5. Renal Tubular Acidosis an Adverse Effect of PD-1 Inhibitor Immunotherapy

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    Sandy El Bitar

    2018-01-01

    Full Text Available Immune checkpoint blockade therapy is gaining popularity among oncologists for treatment of solid and hematologic malignancies. The widespread use of these agents resulted in increasing incidence of renal immune-related adverse events. Reported renal toxicity described so far includes acute interstitial nephritis, minimal change disease, and immune complex glomerulonephritis. We report the case of a 79-year-old female with metastatic non-small cell lung cancer on anti-PD-1 therapy nivolumab. After the 4th administration of nivolumab, the treatment course was complicated with normal anion gap metabolic acidosis. Urine and blood studies were in favor of distal renal tubular acidosis (RTA. Following a negative workup for an underlying etiology, immunotherapy-induced RTA was suspected. Withholding of the offending agent and initiation of steroid therapy resulted in adequate response. The present report provides the first presentation of RTA as a renal immune-related adverse event secondary to nivolumab. Nephrologists and oncologists should be familiar with potentially life-threatening renal side effects induced by immune checkpoint inhibitors.

  6. Distal renal tubular acidosis and quadriparaesis in Sjögren′s syndrome: A cunning congregate

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    Arundhati G Diwan

    2014-01-01

    Full Text Available Sjögren′s syndrome (SS is a chronic autoimmune disease, chiefly affecting the exocrine glandular function of salivary glands and lacrimal glands. Rarely, it involves the kidneys, central and peripheral nervous system, muscloskeletal apparatus and lungs. We report a rare constellation of SS with distal renal tubular acidosis and quadriparaesis in a young female. History of quadriparaesis was acute, with rapid progression. Supplementary treatment for severe hypokalemia was instituted at the earliest, lest the patient develop respiratory muscle weakness. Concomitantly, metabolic acidosis with alkaline urine was suspected and subsequently investigated. Eventually, this was attributed to impaired renal acidification of urine in the distal tubules. History of dryness of eyes and mouth since 6 months justified salivary gland biopsy. The results yielded a lymphocytic infiltrative pathology strongly favoring SS. The patient benefited from prompt potassium replacement therapy and had complete resolution over the next week. Supportive treatment for predictable manifestations was continued along with potassium supplements.

  7. Bilateral Proximal Femur Fractures in a Patient with Renal Tubular Acidosis: A Case Report

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    Charl SS

    2018-03-01

    Full Text Available The diagnosis of pathological fractures is on the rise. The morbidity involved does not only burden the patient and their families but it has a great toll on the healthcare system as well. Early identification of the patient at risk is an invaluable tool to cut cost and improve the patient’s quality of life. Multiple renal pathologies have been highlighted in relation to the risk of pathological fractures; however, complications in renal tubular acidosis have been rarely documented. Nevertheless, prompt action with adequate and relevant patient education ultimately can reduce the associated morbidity. We present a case of poor control of the disease and its debilitating pathological fracture complications.

  8. Uric Acid Induces Renal Inflammation via Activating Tubular NF-κB Signaling Pathway

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    Zhou, Yang; Fang, Li; Jiang, Lei; Wen, Ping; Cao, Hongdi; He, Weichun; Dai, Chunsun; Yang, Junwei

    2012-01-01

    Inflammation is a pathologic feature of hyperuricemia in clinical settings. However, the underlying mechanism remains unknown. Here, infiltration of T cells and macrophages were significantly increased in hyperuricemia mice kidneys. This infiltration of inflammatory cells was accompanied by an up-regulation of TNF-α, MCP-1 and RANTES expression. Further, infiltration was largely located in tubular interstitial spaces, suggesting a role for tubular cells in hyperuricemia-induced inflammation. In cultured tubular epithelial cells (NRK-52E), uric acid, probably transported via urate transporter, induced TNF-α, MCP-1 and RANTES mRNA as well as RANTES protein expression. Culture media of NRK-52E cells incubated with uric acid showed a chemo-attractive ability to recruit macrophage. Moreover uric acid activated NF-κB signaling. The uric acid-induced up-regulation of RANTES was blocked by SN 50, a specific NF-κB inhibitor. Activation of NF-κB signaling was also observed in tubule of hyperuricemia mice. These results suggest that uric acid induces renal inflammation via activation of NF-κB signaling. PMID:22761883

  9. Sjögren syndrome presenting with hypopotassemic periodic paralysis due to renal tubular acidosis

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    Ataoglu, Esra Hayriye; Demir, Betul; Tuna, Mazhar; Çavus, Bilger; Cetin, Faik; Temiz, Levent Umit; Ozturk, Savas; Yenigun, Mustafa

    2012-01-01

    Summary Background: Sjögren syndrome (SS) is an autoimmune-lymphoproliferative disorder characterized by mononuclear cell infiltration of exocrine glands. Clinically, Sjögren syndrome (SS) has a wide spectrum, varying from autoimmune exocrinopathy to systemic involvement. There have been few cases reporting that primary SS developed with distal renal tubular acidosis clinically. Case Report: Here, we present a case with primary Sjögren syndrome accompanied by hypopotassemic paralysis due to renal tubular acidosis. Severe hypopotassemia, hyperchloremic metabolic acidosis, alkaline urine and disorder in urinary acidification test were observed in the biochemical examination of the 16-year-old female patient, who had applied to our clinic for extreme loss of muscle force. After the examinations it was determined that the patient had developed Type 1 RTA (distal RTA) due to primary Sjögren syndrome. Potassium and alkaline replacement was made and an immediate total recovery was achieved. Conclusions: Hypopotassemic paralysis due to primary Sjögren syndrome is a rare but severe disorder that could lead to death if not detected early and cured appropriately. Thus, effective treatment should be immediately initiated in cases where severe hypopotassemia is accompanied by metabolic acidosis, and the cases should also be examined for extraglandular involvement of SS. PMID:23569525

  10. The association between serum vitamin D levels and renal tubular dysfunction in a general population exposed to cadmium in China.

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    Chen, Xiao; Dai, Yan; Wang, Zhongqiu; Zhu, Guoying; Ding, Xiaoqiang; Jin, Taiyi

    2018-01-01

    Cadmium exposure can cause renal tubular dysfunction. Recent studies show that vitamin D can play multiple roles in the body. However, the association between serum vitamin D levels and renal tubular dysfunction in a general population exposed to cadmium has not been clarified. We performed study to assess the effects of cadmium on serum 25(OH) D levels and the association between serum 25(OH) D levels and renal tubular dysfunction in a population environmentally exposed to cadmium. A total of 133 subjects living in control area and two cadmium polluted areas were included in the present study. Cadmium in urine (UCd) and blood (BCd), urinary β2Microglobulin (UBMG), urinary retinol binding protein (URBP) and serum 25 (OH) D were determined. Logistic regression was used to estimate the association between 25 (OH) D and prevalence of renal tubular dysfunction. No significant differences were observed in serum 25(OH) D levels among the four quartile of UCd and BCd after adjusting with cofounders. After adjusted with the confounders, the odds ratio (OR) of subjects with 25(OH) D ≥ 40 ng/ml were 0.20 (95%CI: 0.1-0.8) if UBMG was chosen as indicators of renal dysfunction and 0.28 (95%CI: 0.1-1.1) if URBP was chosen as indicators of renal dysfunction, compared with those with 25(OH) D < 30 ng/ml, respectively. Similar results were observed in those subjects living in cadmium polluted areas or with high level of UCd or BCd. Our data indicated that cadmium exposure did not affect serum 25(OH) D level and high 25 (OH) D levels were associated with a decreased risk of renal tubular dysfunction induced by cadmium.

  11. Systemic lupus erythematosus associated with type 4 renal tubular acidosis: a case report and review of the literature

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    Young Larry

    2011-03-01

    Full Text Available Abstract Introduction Type 4 renal tubular acidosis is an uncommon clinical manifestation of systemic lupus erythematosus and has been reported to portend a poor prognosis. To the best of our knowledge, this is the first case report which highlights the successful management of a patient with systemic lupus erythematosus complicated by type 4 renal tubular acidosis who did not do poorly. Case presentation A 44-year-old Hispanic woman developed a non-anion gap hyperkalemic metabolic acidosis consistent with type 4 renal tubular acidosis while being treated in the hospital for recently diagnosed systemic lupus erythematosus with multi-organ involvement. She responded well to treatment with corticosteroids, hydroxychloroquine and mycophenolate mofetil. Normal renal function was achieved prior to discharge and remained normal at the patient's one-month follow-up examination. Conclusion This case increases awareness of an uncommon association between systemic lupus erythematosus and type 4 renal tubular acidosis and suggests a positive impact of early diagnosis and appropriate immunosuppressive treatment on the patient's outcome.

  12. Urinary excretion of beta 2-glycoprotein-1 (apolipoprotein H) and other markers of tubular malfunction in "non-tubular" renal disease.

    Science.gov (United States)

    Flynn, F V; Lapsley, M; Sansom, P A; Cohen, S L

    1992-07-01

    To determine whether urinary beta 2-glycoprotein-1 assays can provide improved discrimination between chronic renal diseases which are primarily of tubular or glomerular origin. Urinary beta 2-glycoprotein-1, retinol-binding protein, alpha 1-microglobulin, beta 2-microglobulin, N-acetyl-beta-D-glucosa-minidase and albumin were measured in 51 patients with primary glomerular disease, 23 with obstructive nephropathy, and 15 with polycystic kidney disease, and expressed per mmol of creatinine. Plasma beta 2-glycoprotein-1 was assayed in 52 patients and plasma creatinine in all 89. The findings were compared between the diagnostic groups and with previously published data relating to primary tubular disorders. All 31 patients with plasma creatinine greater than 200 mumol/l excreted increased amounts of beta 2-glycoprotein-1, retinol-binding protein, and alpha 1-microglobulin, and 29 had increased N-acetyl-beta-D-glucosaminidase; the quantities were generally similar to those found in comparable patients with primary tubular pathology. Among 58 with plasma creatinine concentrations under 200 mumol/l, increases in beta 2-glycoprotein-1, retinol-binding protein, and alpha 1-microglobulin excretion were less common and much smaller, especially in those with obstructive nephropathy and polycystic disease. The ratios of the excretion of albumin to the other proteins provided the clearest discrimination between the patients with glomerular or tubular malfunction, but an area of overlap was present which embraced those with obstructive nephropathy and polycystic disease. Increased excretion of beta 2-glycoprotein-1 due to a raised plasma concentration or diminution of tubular reabsorption, or both, is common in all the forms of renal disease investigated, and both plasma creatinine and urinary albumin must be taken into account when interpreting results. Ratios of urinary albumin: beta 2-glycoprotein-1 greater than 1000 are highly suggestive of primary glomerular disease and

  13. Role of mitochondrial permeability transition in human renal tubular epithelial cell death induced by aristolochic acid

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    Qi Xinming; Cai Yan; Gong Likun; Liu Linlin; Chen Fangping; Xiao Ying; Wu Xiongfei; Li Yan; Xue Xiang; Ren Jin

    2007-01-01

    Aristolochic acid (AA), a natural nephrotoxin and carcinogen, can induce a progressive tubulointerstitial nephropathy. However, the mechanism by which AA causes renal injury remains largely unknown. Here we reported that the mitochondrial permeability transition (MPT) plays an important role in the renal injury induced by aristolochic acid I (AAI). We found that in the presence of Ca 2+ , AAI caused mitochondrial swelling, leakage of Ca 2+ , membrane depolarization, and release of cytochrome c in isolated kidney mitochondria. These alterations were suppressed by cyclosporin A (CsA), an agent known to inhibit MPT. Culture of HK-2 cell, a human renal tubular epithelial cell line for 24 h with AAI caused a decrease in cellular ATP, mitochondrial membrane depolarization, cytochrome c release, and increase of caspase 3 activity. These toxic effects of AAI were attenuated by CsA and bongkrekic acid (BA), another specific MPT inhibitor. Furthermore, AAI greatly inhibited the activity of mitochondrial adenine nucleotide translocator (ANT) in isolated mitochondria. We suggested that ANT may mediate, at least in part, the AAI-induced MPT. Taken together, these results suggested that MPT plays a critical role in the pathogenesis of HK-2 cell injury induced by AAI and implied that MPT might contribute to human nephrotoxicity of aristolochic acid

  14. Autophagy Limits Endotoxemic Acute Kidney Injury and Alters Renal Tubular Epithelial Cell Cytokine Expression.

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    Jeremy S Leventhal

    Full Text Available Sepsis related acute kidney injury (AKI is a common in-hospital complication with a dismal prognosis. Our incomplete understanding of disease pathogenesis has prevented the identification of hypothesis-driven preventive or therapeutic interventions. Increasing evidence in ischemia-reperfusion and nephrotoxic mouse models of AKI support the theory that autophagy protects renal tubular epithelial cells (RTEC from injury. However, the role of RTEC autophagy in septic AKI remains unclear. We observed that lipopolysaccharide (LPS, a mediator of gram-negative bacterial sepsis, induces RTEC autophagy in vivo and in vitro through TLR4-initiated signaling. We modeled septic AKI through intraperitoneal LPS injection in mice in which autophagy-related protein 7 was specifically knocked out in the renal proximal tubules (ATG7KO. Compared to control littermates, ATG7KO mice developed more severe renal dysfunction (24hr BUN 100.1mg/dl +/- 14.8 vs 54.6mg/dl +/- 11.3 and parenchymal injury. After injection with LPS, analysis of kidney lysates identified higher IL-6 expression and increased STAT3 activation in kidney lysates from ATG7KO mice compared to controls. In vitro experiments confirmed an altered response to LPS in RTEC with genetic or pharmacological impairment of autophagy. In conclusion, RTEC autophagy protects against endotoxin induced injury and regulates downstream effects of RTEC TLR4 signaling.

  15. BAG3 regulates ECM accumulation in renal proximal tubular cells induced by TGF-β1.

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    Du, Feng; Li, Si; Wang, Tian; Zhang, Hai-Yan; Li, De-Tian; Du, Zhen-Xian; Wang, Hua-Qin; Wang, Yan-Qiu

    2015-01-01

    Previously we have demonstrated that Bcl-2-associated athanogene 3 (BAG3) is increased in renal fibrosis using a rat unilateral ureteral obstruction model. The current study investigated the role of BAG3 in renal fibrosis using transforming growth factor (TGF)-β1-treated human proximal tubular epithelial (HK-2) cells. An upregulation of BAG3 in vitro models was observed, which correlated with the increased synthesis of extracellular matrix (ECM) proteins and expression of tissue-type plasminogen activator inhibitor (PAI)-1. Blockade of BAG3 induction by shorting hairpin RNA suppressed the expression of ECM proteins but had no effect on PAI-1 expression induced by TGF-β1. Forced overexpression of BAG3 selectively increased collagens. TGF-β1-induced BAG3 expression in HK-2 cells was attenuated by ERK1/2 and JNK MAPK inhibitors. In addition, forced BAG3 overexpression blocked attenuation of collagens expression by ERK1/2 and JNK inhibitors. These data suggest that ERK1/2 and JNK signaling events are involved in modulating the expression of BAG3, which would ultimately contribute to renal fibrosis by enhancing the synthesis and deposition of ECM proteins.

  16. Autophagy activation promotes removal of damaged mitochondria and protects against renal tubular injury induced by albumin overload.

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    Tan, Jin; Wang, Miaohong; Song, Shuling; Miao, Yuyang; Zhang, Qiang

    2018-01-10

    Proteinuria (albuminuria) is an important cause of aggravating tubulointerstitial injury. Previous studies have shown that autophagy activation can alleviate renal tubular epithelial cell injury caused by urinary protein, but the mechanism is not clear. Here, we investigated the role of clearance of damaged mitochondria in this protective effect. We found that albumin overload induces a significant increase in turnover of LC3-II and decrease in p62 protein level in renal proximal tubular (HK-2) cells in vitro. Albumin overload also induces an increase in mitochondrial damage. ALC, a mitochondrial torpent, alleviates mitochondrial damage induced by albumin overload and also decreases autophagy, while mitochondrial damage revulsant CCCP further increases autophagy. Furthermore, pretreatment of HK-2 cells with rapamycin reduced the amount of damaged mitochondria and the level of apoptosis induced by albumin overload. In contrast, blocking autophagy with chloroquine exerted an opposite effect. Taken together, our results indicated autophagy activation promotes removal of damaged mitochondria and protects against renal tubular injury caused by albumin overload. This further confirms previous research that autophagy activation is an adaptive response in renal tubular epithelial cells after urinary protein overload.

  17. Whole-exome sequencing as a diagnostic tool for distal renal tubular acidosis

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    Paula Cristina Barros Pereira

    2015-11-01

    Full Text Available Objective: Distal renal tubular acidosis (dRTA is characterized by metabolic acidosis due to impaired renal acid excretion. The aim of this study was to demonstrate the genetic diagnosis of four children with dRTA through use of whole-exome sequencing. Methods: Two unrelated families were selected; a total of four children with dRTA and their parents, in order to perform whole-exome sequencing. Hearing was preserved in both children from the first family, but not in the second, wherein a twin pair had severe deafness. Whole-exome sequencing was performed in two pooled samples and findings were confirmed with Sanger sequencing method. Results: Two mutations were identified in the ATP6V0A4 and ATP6V1B1 genes. In the first family, a novel mutation in the exon 13 of the ATP6V0A4 gene with a single nucleotide change GAC → TAC (c.1232G>T was found, which caused a substitution of aspartic acid to tyrosine in position 411. In the second family, a homozygous recurrent mutation with one base-pair insertion (c.1149_1155insC in exon 12 of the ATP6V1B1 gene was detected. Conclusion: These results confirm the value of whole-exome sequencing for the study of rare and complex genetic nephropathies, allowing the identification of novel and recurrent mutations. Furthermore, for the first time the application of this molecular method in renal tubular diseases has been clearly demonstrated. Resumo: Objetivo: A acidose tubular renal distal (ATRd é caracterizada por acidose metabólica devido a excreção renal de ácido prejudicada. O objetivo deste artigo é apresentar o diagnóstico genético de quatro crianças com ATRd utilizando o sequenciamento total do exoma. Métodos: Selecionamos duas famílias não relacionadas, totalizando quatro crianças com ATRd e seus pais, para realizar o sequenciamento total do exoma. A audição foi preservada em ambas as crianças da família um, porém em nenhuma criança da família dois, na qual um par de gêmeas teve

  18. Intracellular kinases mediate increased translation and secretion of netrin-1 from renal tubular epithelial cells.

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    Calpurnia Jayakumar

    Full Text Available BACKGROUND: Netrin-1 is a laminin-related secreted protein, is highly induced after tissue injury, and may serve as a marker of injury. However, the regulation of netrin-1 production is not unknown. Current study was carried out in mouse and mouse kidney cell line (TKPTS to determine the signaling pathways that regulate netrin-1 production in response to injury. METHODS AND PRINCIPAL FINDINGS: Ischemia reperfusion injury of the kidney was induced in mice by clamping renal pedicle for 30 minutes. Cellular stress was induced in mouse proximal tubular epithelial cell line by treating with pervanadate, cisplatin, lipopolysaccharide, glucose or hypoxia followed by reoxygenation. Netrin-1 expression was quantified by real time RT-PCR and protein production was quantified using an ELISA kit. Cellular stress induced a large increase in netrin-1 production without increase in transcription of netrin-1 gene. Mitogen activated protein kinase, ERK mediates the drug induced netrin-1 mRNA translation increase without altering mRNA stability. CONCLUSION: Our results suggest that netrin-1 expression is suppressed at the translational level and MAPK activation leads to rapid translation of netrin-1 mRNA in the kidney tubular epithelial cells.

  19. Intracellular Kinases Mediate Increased Translation and Secretion of Netrin-1 from Renal Tubular Epithelial Cells

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    Jayakumar, Calpurnia; Mohamed, Riyaz; Ranganathan, Punithavathi Vilapakkam; Ramesh, Ganesan

    2011-01-01

    Background Netrin-1 is a laminin-related secreted protein, is highly induced after tissue injury, and may serve as a marker of injury. However, the regulation of netrin-1 production is not unknown. Current study was carried out in mouse and mouse kidney cell line (TKPTS) to determine the signaling pathways that regulate netrin-1 production in response to injury. Methods and Principal Findings Ischemia reperfusion injury of the kidney was induced in mice by clamping renal pedicle for 30 minutes. Cellular stress was induced in mouse proximal tubular epithelial cell line by treating with pervanadate, cisplatin, lipopolysaccharide, glucose or hypoxia followed by reoxygenation. Netrin-1 expression was quantified by real time RT-PCR and protein production was quantified using an ELISA kit. Cellular stress induced a large increase in netrin-1 production without increase in transcription of netrin-1 gene. Mitogen activated protein kinase, ERK mediates the drug induced netrin-1 mRNA translation increase without altering mRNA stability. Conclusion Our results suggest that netrin-1 expression is suppressed at the translational level and MAPK activation leads to rapid translation of netrin-1 mRNA in the kidney tubular epithelial cells. PMID:22046354

  20. Renal Tubular Acidosis after Jejunoileal Bypass for Morbid Obesity: role of secondary hyperparathyroidism

    DEFF Research Database (Denmark)

    Andersen, NN; Ladefoged, NN

    1991-01-01

    The effect of calcium infusion was studied in patients with renal tubular acidosis (RTA) and secondary hyperparathyroidism. Both developed after jejunoileal bypass operation (JIB) for morbid obesity. In three of four cases the acidification defect was abolished, probably due to a decrease of serum...... parathyroid hormone. As we found RTA in 9% (95% confidence limits 2-21%) of our patients, screening for acidosis is recommended in obesity patients after malabsorptive operations. RTA can be verified through an ammonium loading test. Before deciding on re-establishing bowel continuity due to RTA, we suggest...... and vitamin D supplementation. If RTA can be abolished through correction of calcium homeostasis, reoperation may be avoided. Before deciding on re-establishing bowel continuity in JIB patients with RTA, we therefore suggest that patients be evaluated for secondary hyperparathyroidism and any calcium...

  1. The need for genetic study to diagnose some cases of distal renal tubular acidosis.

    Science.gov (United States)

    Heras Benito, Manuel; Garcia-Gonzalez, Miguel A; Valdenebro Recio, María; Molina Ordás, Álvaro; Callejas Martínez, Ramiro; Rodríguez Gómez, María Astrid; Calle García, Leonardo; Sousa Silva, Lisbeth; Fernández-Reyes Luis, María José

    We describe the case of a young woman who was diagnosed with advanced kidney disease, with an incidental finding of nephrocalcinosis of unknown aetiology, having been found asymptomatic throughout her life. The genetic study by panels of known genes associated with tubulointerstitial disease allowed us to discover autosomal dominant distal renal tubular acidosis associated with a de novo mutation in exon 14 of the SLC4A1 gene, which would have been impossible to diagnose clinically due to the advanced nature of the kidney disease when it was discovered. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  2. Albumin Overload and PINK1/Parkin Signaling-Related Mitophagy in Renal Tubular Epithelial Cells.

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    Tan, Jin; Xie, Qi; Song, Shuling; Miao, Yuyang; Zhang, Qiang

    2018-03-01

    BACKGROUND Albumin, as a major urinary protein component, is a risk factor for chronic kidney disease progression. Mitochondrial dysfunction is one of the main causes of albumin-induced proximal tubule cells injury. Mitophagy is considered as a pivotal protective mechanism for the elimination of dysfunctional mitochondria. The objective of this research was to determine whether albumin overload-induced mitochondrial dysfunction can activate PINK1/Parkin-mediated mitophagy in renal tubular epithelial cells (TECs). MATERIAL AND METHODS Immunofluorescence assay and Western blot assay were used to detect the effects of albumin overload on autophagy marker protein LC3. Transmission electron microscopy and Western blot assay were used to investigate the role of albumin in mitochondrial injury. Western blot assay and co-localization of acidic lysosomes and mitochondria assay were employed to detect the activation of mitophagy induced by albumin. Finally, we explored the role of PINK1/Parkin signaling in albumin-induced mitophagy by inhibiting mitophagy by knockdown of PARK2 (Parkin) level. RESULTS Immunofluorescence and Western blot results showed that the expression level of LC3-II increased, and the maximum increase point was observed after 8 h of albumin treatment. Transmission electron microscopy results demonstrated that albumin overload-induced mitochondrial injury and quantity of autophagosomes increased. Additionally, expression of PINK1 and cytosolic cytochrome C increased and mitochondria cytochrome C decreased in the albumin group. The co-localization of acidic lysosomes and mitochondria demonstrated that the number of albumin overload-induced mitophagy-positive dots increased. The transient transfection of PARK2 siRNA result showed knockdown of the expression level of PARK2 can inhibit mitophagy induced by albumin. CONCLUSIONS In conclusion, our study suggests that mitochondrial dysfunction activates the PINK1/Parkin signaling and mitophagy in renal tubular

  3. A paracrine mechanism involving renal tubular cells, adipocytes and macrophages promotes kidney stone formation in a simulated metabolic syndrome environment.

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    Zuo, Li; Tozawa, Keiichi; Okada, Atsushi; Yasui, Takahiro; Taguchi, Kazumi; Ito, Yasuhiko; Hirose, Yasuhiko; Fujii, Yasuhiro; Niimi, Kazuhiro; Hamamoto, Shuzo; Ando, Ryosuke; Itoh, Yasunori; Zou, Jiangang; Kohri, Kenjiro

    2014-06-01

    We developed an in vitro system composed of renal tubular cells, adipocytes and macrophages to simulate metabolic syndrome conditions. We investigated the molecular communication mechanism of these cells and their involvement in kidney stone formation. Mouse renal tubular cells (M-1) were cocultured with adipocytes (3T3-L1) and/or macrophages (RAW264.7). Calcium oxalate monohydrate crystals were exposed to M-1 cells after 48-hour coculture and the number of calcium oxalate monohydrate crystals adherent to the cells was quantified. The expression of cocultured medium and M-1 cell inflammatory factors was analyzed by enzyme-linked immunosorbent assay and quantitative polymerase chain reaction, respectively. The inflammatory markers MCP-1, OPN and TNF-α were markedly up-regulated in cocultured M-1 cells. OPN expression increased in M-1 cells cocultured with RAW264.7 cells while MCP-1 and TNF-α were over expressed in M-1 cells cocultured with 3T3-L1 cells. Coculturing M-1 cells simultaneously with 3T3-L1 and RAW264.7 cells resulted in a significant increase in calcium oxalate monohydrate crystal adherence to M-1 cells. Inflammatory cytokine changes were induced by coculturing renal tubular cells with adipocytes and/or macrophages without direct contact, indicating that crosstalk between adipocytes/macrophages and renal tubular cells was mediated by soluble factors. The susceptibility to urolithiasis of patients with metabolic syndrome might be due to aggravated inflammation of renal tubular cells triggered by a paracrine mechanism involving these 3 cell types. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  4. Complicated pregnancies in inherited distal renal tubular acidosis: importance of acid-base balance.

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    Seeger, Harald; Salfeld, Peter; Eisel, Rüdiger; Wagner, Carsten A; Mohebbi, Nilufar

    2017-06-01

    Inherited distal renal tubular acidosis (dRTA) is caused by impaired urinary acid excretion resulting in hyperchloremic metabolic acidosis. Although the glomerular filtration rate (GFR) is usually preserved, and hypertension and overt proteinuria are absent, it has to be considered that patients with dRTA also suffer from chronic kidney disease (CKD) with an increased risk for adverse pregnancy-related outcomes. Typical complications of dRTA include severe hypokalemia leading to cardiac arrhythmias and paralysis, nephrolithiasis and nephrocalcinosis. Several physiologic changes occur in normal pregnancy including alterations in acid-base and electrolyte homeostasis as well as in GFR. However, data on pregnancy in women with inherited dRTA are scarce. We report the course of pregnancy in three women with hereditary dRTA. Complications observed were severe metabolic acidosis, profound hypokalemia aggravated by hyperemesis gravidarum, recurrent urinary tract infection (UTI) and ureteric obstruction leading to renal failure. However, the outcome of all five pregnancies (1 pregnancy each for mothers n. 1 and 2; 3 pregnancies for mother n. 3) was excellent due to timely interventions. Our findings highlight the importance of close nephrologic monitoring of women with inherited dRTA during pregnancy. In addition to routine assessment of creatinine and proteinuria, caregivers should especially focus on acid-base status, plasma potassium and urinary tract infections. Patients should be screened for renal obstruction in the case of typical symptoms, UTI or renal failure. Furthermore, genetic identification of the underlying mutation may (a) support early nephrologic referral during pregnancy and a better management of the affected woman, and (b) help to avoid delayed diagnosis and reduce complications in affected newborns.

  5. Comorbid renal tubular damage and hypoalbuminemia exacerbate cardiac prognosis in patients with chronic heart failure.

    Science.gov (United States)

    Otaki, Yoichiro; Watanabe, Tetsu; Takahashi, Hiroki; Funayama, Akira; Kinoshita, Daisuke; Yokoyama, Miyuki; Takahashi, Tetsuya; Nishiyama, Satoshi; Arimoto, Takanori; Shishido, Tetsuro; Miyamoto, Takuya; Konta, Tsuneo; Kubota, Isao

    2016-02-01

    Renal tubular damage (RTD) and hypoalbuminemia are risks for poor prognosis in patients with chronic heart failure (CHF). Renal tubules play a pivotal role in amino acid and albumin reabsorption, which maintain serum albumin levels. The aims of the present study were to (1) examine the association of RTD with hypoalbuminemia, and (2) assess the prognostic importance of comorbid RTD and hypoalbuminemia in patients with CHF. We measured N-acetyl-β-D-glucosamidase (NAG) levels and the urinary β2-microglobulin to creatinine ratio (UBCR) in 456 patients with CHF. RTD was defined as UBCR ≥ 300 μg/g or NAG ≥ 14.2 U/g. There were moderate correlations between RTD markers and serum albumin (NAG, r = -0.428, P < 0.0001; UBCR, r = -0.399, P < 0.0001). Multivariate logistic analysis showed that RTD was significantly related to hypoalbuminemia in patients with CHF. There were 134 cardiac events during a median period of 808 days. The comorbidity of RTD and hypoalbuminemia was increased with advancing New York Heart Association functional class. Multivariate Cox proportional hazard regression analysis showed that the presence of RTD and hypoalbuminemia was associated with cardiac events. The net reclassification index was significantly improved by adding RTD and hypoalbuminemia to the basic risk factors. Comorbid RTD and hypoalbuminemia are frequently observed and increase the risk for extremely poor outcome in patients with CHF.

  6. Epoetin Delta Reduces Oxidative Stress in Primary Human Renal Tubular Cells

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    Annelies De Beuf

    2010-01-01

    Full Text Available Erythropoietin (EPO exerts (renal tissue protective effects. Since it is unclear whether this is a direct effect of EPO on the kidney or not, we investigated whether EPO is able to protect human renal tubular epithelial cells (hTECs from oxidative stress and if so which pathways are involved. EPO (epoetin delta could protect hTECs against oxidative stress by a dose-dependent inhibition of reactive oxygen species formation. This protective effect is possibly related to the membranous expression of the EPO receptor (EPOR since our data point to the membranous EPOR expression as a prerequisite for this protective effect. Oxidative stress reduction went along with the upregulation of renoprotective genes. Whilst three of these, heme oxygenase-1 (HO-1, aquaporin-1 (AQP-1, and B-cell CLL/lymphoma 2 (Bcl-2 have already been associated with EPO-induced renoprotection, this study for the first time suggests carboxypeptidase M (CPM, dipeptidyl peptidase IV (DPPIV, and cytoglobin (Cygb to play a role in this process.

  7. Ultrastructural study of electron dense deposits in renal tubular basement membrane: prevalence and relationship to epithelial atrophy.

    Science.gov (United States)

    Yong, Jim L C; Killingsworth, Murray C

    2014-08-01

    This study reports the prevalence of immune deposits associated with the proximal and distal tubules in a series of routine renal biopsies received in our department during a single calendar year. From 87 cases, 65 (74%) were found to have glomerular immune deposits by immunofluorescence. Tubular immune deposits were found in 12 cases (18%), 3 of which had no glomerular deposits. By transmission electron microscopy (EM), 58 cases (66%) were found to have deposits of granular or vesicular material associated with the tubular basement membranes (TBM). Finely granular electron dense deposits appeared to correspond to the immune deposits seen by immunofluorescence microscopy (IF) and may be a sensitive marker of immune deposition.

  8. Osteomalacia complicating renal tubular acidosis in association with Sjogren′s syndrome

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    Zohra El Ati

    2014-01-01

    Full Text Available Renal involvement in Sjogren′s syndrome (SS is not uncommon and may precede other complaints. Tubulointerstitial nephritis is the most common renal disease in SS and may lead to renal tubular acidosis (RTA, which in turn may cause osteomalacia. Nevertheless, osteomalacia rarely occurs as the first manifestation of a renal tubule disorder due to SS. We herewith describe a 43-year-old woman who was admitted to our hospital for weakness, lumbago and inability to walk. X-ray of the long bones showed extensive demineralization of the bones. Laboratory investigations revealed chronic kidney disease with serum creatinine of 2.3 mg/dL and creatinine clearance of 40 mL/min, hypokalemia (3.2 mmol/L, hypophosphatemia (0.4 mmol/L, hypocalcemia (2.14 mmol/L and hyperchloremic metabolic acidosis (chlorine: 114 mmol/L; alkaline reserve: 14 mmol/L. The serum alkaline phosphatase levels were elevated. The serum levels of 25-hydroxyvitamin D and 1,25-dihydroxy vitamin D were low and borderline low, respectively, and the parathyroid hormone level was 70 pg/L. Urinalysis showed inappropriate alkaline urine (urinary PH: 7, glycosuria with normal blood glucose, phosphaturia and uricosuria. These values indicated the presence of both distal and proximal RTA. Our patient reported dryness of the mouth and eyes and Schirmer′s test showed xerophthalmia. An accessory salivary gland biopsy showed changes corresponding to stage IV of Chisholm and Masson score. Kidney biopsy showed diffuse and severe tubulo-interstitial nephritis with dense lymphoplasmocyte infiltrates. Sicca syndrome and renal interstitial infiltrates indicated SS as the underlying cause of the RTA and osteomalacia. The patient received alkalinization, vitamin D (Sterogyl ®, calcium supplements and steroids in an initial dose of 1 mg/kg/day, tapered to 10 mg daily. The prognosis was favorable and the serum creatinine level was 1.7 mg/dL, calcium was 2.2 mmol/L and serum phosphate was 0.9 mmol/L.

  9. Augmenter of liver regeneration inhibits TGF-β1-induced renal tubular epithelial-to-mesenchymal transition via suppressing TβR II expression in vitro

    International Nuclear Information System (INIS)

    Liao, Xiao-hui; Zhang, Ling; Chen, Guo-tao; Yan, Ru-yu; Sun, Hang; Guo, Hui; Liu, Qi

    2014-01-01

    Tubular epithelial-to-mesenchymal transition (EMT) plays a crucial role in the progression of renal tubular interstitial fibrosis (TIF), which subsequently leads to chronic kidney disease (CKD) and eventually, end-stage renal disease (ESRD). We propose that augmenter of liver regeneration (ALR), a member of the newly discovered ALR/Erv1 protein family shown to ameliorate hepatic fibrosis, plays a similar protective role in renal tubular cells and has potential as a new treatment option for CKD. Here, we showed that recombinant human ALR (rhALR) inhibits EMT in renal tubular cells by antagonizing activation of the transforming growth factor-β1 (TGF-β1) signaling pathway. Further investigation revealed that rhALR suppresses the expression of TGF-β receptor type II (TβR II) and significantly alleviates TGF-β1-induced phosphorylation of Smad2 and nuclear factor-κB (NF-κB). No apparent adverse effects were observed upon the addition of rhALR alone to cells. These findings collectively suggest that ALR plays a role in inhibiting progression of renal tubular EMT, supporting its potential utility as an effective antifibrotic strategy to reverse TIF in CKD. - Highlights: • ALR is involved in the pathological progression of renal EMT in NRK-52E cells. • ALR suppresses the expression of TβRII and the phosphorylation of Smad2 and NF-κB. • ALR plays a role in inhibiting progression of renal tubular EMT

  10. Augmenter of liver regeneration inhibits TGF-β1-induced renal tubular epithelial-to-mesenchymal transition via suppressing TβR II expression in vitro

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    Liao, Xiao-hui [Department of Nephrology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China); Zhang, Ling, E-mail: lindazhang8508@hotmail.com [Department of Nephrology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China); Chen, Guo-tao; Yan, Ru-yu [Department of Nephrology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China); Sun, Hang; Guo, Hui [Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China); Liu, Qi, E-mail: txzzliuqi@163.com [Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China)

    2014-10-01

    Tubular epithelial-to-mesenchymal transition (EMT) plays a crucial role in the progression of renal tubular interstitial fibrosis (TIF), which subsequently leads to chronic kidney disease (CKD) and eventually, end-stage renal disease (ESRD). We propose that augmenter of liver regeneration (ALR), a member of the newly discovered ALR/Erv1 protein family shown to ameliorate hepatic fibrosis, plays a similar protective role in renal tubular cells and has potential as a new treatment option for CKD. Here, we showed that recombinant human ALR (rhALR) inhibits EMT in renal tubular cells by antagonizing activation of the transforming growth factor-β1 (TGF-β1) signaling pathway. Further investigation revealed that rhALR suppresses the expression of TGF-β receptor type II (TβR II) and significantly alleviates TGF-β1-induced phosphorylation of Smad2 and nuclear factor-κB (NF-κB). No apparent adverse effects were observed upon the addition of rhALR alone to cells. These findings collectively suggest that ALR plays a role in inhibiting progression of renal tubular EMT, supporting its potential utility as an effective antifibrotic strategy to reverse TIF in CKD. - Highlights: • ALR is involved in the pathological progression of renal EMT in NRK-52E cells. • ALR suppresses the expression of TβRII and the phosphorylation of Smad2 and NF-κB. • ALR plays a role in inhibiting progression of renal tubular EMT.

  11. GSTA3 Attenuates Renal Interstitial Fibrosis by Inhibiting TGF-Beta-Induced Tubular Epithelial-Mesenchymal Transition and Fibronectin Expression.

    Directory of Open Access Journals (Sweden)

    Yun Xiao

    Full Text Available Tubular epithelial-mesenchymal transition (EMT has been widely accepted as the underlying mechanisms of renal interstitial fibrosis (RIF. The production of reactive oxygen species (ROS plays a vital role in tubular EMT process. The purpose of this study was to investigate the involved molecular mechanisms in TGF-beta-induced EMT and identify the potential role of glutathione S-transferase alpha 3 (GSTA3 in this process. The iTRAQ screening was performed to identify protein alterations of the rats underwent unilateral-ureteral obstruction (UUO. Protein expression of GSTA3 in patients with obstructive nephropathy and UUO rats was detected by immunohistochemistry. Protein and mRNA expression of GSTA3 in UUO rats and NRK-52E cells were determined by Western blot and RT-PCR. siRNA and overexpression plasmid were transfected specifically to assess the role of GSTA3 in RIF. The generation of ROS was measured by dichlorofluorescein fluorescence analysis. GSTA3 protein and mRNA expression was significantly reduced in UUO rats. Immunohistochemical analysis revealed that GSTA3 expression was reduced in renal cortex in UUO rats and patients with obstructive nephropathy. Treating with TGF-β1 down-regulated GSTA3 expression in NRK-52E cells, which have been found to be correlated with the decreased expression in E-cadherin and megalin and increased expression in α-smooth muscle actin. Furthermore, knocking down GSTA3 in NRK-52 cells led to increased production of ROS and tubular EMT, whereas overexpressing GSTA3 ameliorated ROS production and prevented the occurrence of tubular EMT. GSTA3 plays a protective role against tubular EMT in renal fibrosis, suggesting GSTA3 is a potential therapeutic target for RIF.

  12. Bmi-1 plays a critical role in the protection from acute tubular necrosis by mobilizing renal stem/progenitor cells.

    Science.gov (United States)

    Lv, Xianhui; Yu, Zhenzhen; Xie, Chunfeng; Dai, Xiuliang; Li, Qing; Miao, Dengshun; Jin, Jianliang

    2017-01-22

    The regeneration of injured tubular cell occurs primarily from intrinsic renal stem/progenitor cells (RSCs) labeled with CD24 and CD133 after acute tubular necrosis (ATN). Bmi-1 plays a crucial role in regulating self-renewal, differentiation and aging of multiple adult stem cells and progenitor cells. Bmi-1 was rapidly elevated in the induction of adult kidney regeneration by renal injury. To determine whether Bmi-1 maintained mobilization of RSCs in the protection from ATN, glycerol-rhabdomyolysis-induced ATN were performed in wild type (WT) and Bmi-1-deficient (Bmi-1 -/- ) mice. Their ATN phenotypes were analyzed; CD24 and CD133 double positive (CD24 + CD133 + ) cells were measured; and the levels of serum urea nitrogen (SUN) and serum creatinine (SCr) were detected. We found that CD24 + CD133 + RSCs were mobilized in WT ATN mice with the increased expression of Bmi-1; Bmi-1 deficiency led to increased tubular cast formation and necrosis, elevated levels of SUN and SCr, decreased tubular proliferation, and immobilized ratio of RSCs in ATN. These findings indicated that Bmi-1 played a critical role in the protection from ATN by maintaining mobilization of RSCs and would be a novel therapeutic target for preventing the progression of ATN. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Bmi-1 plays a critical role in the protection from acute tubular necrosis by mobilizing renal stem/progenitor cells

    International Nuclear Information System (INIS)

    Lv, Xianhui; Yu, Zhenzhen; Xie, Chunfeng; Dai, Xiuliang; Li, Qing; Miao, Dengshun; Jin, Jianliang

    2017-01-01

    The regeneration of injured tubular cell occurs primarily from intrinsic renal stem/progenitor cells (RSCs) labeled with CD24 and CD133 after acute tubular necrosis (ATN). Bmi-1 plays a crucial role in regulating self-renewal, differentiation and aging of multiple adult stem cells and progenitor cells. Bmi-1 was rapidly elevated in the induction of adult kidney regeneration by renal injury. To determine whether Bmi-1 maintained mobilization of RSCs in the protection from ATN, glycerol-rhabdomyolysis-induced ATN were performed in wild type (WT) and Bmi-1-deficient (Bmi-1 −/− ) mice. Their ATN phenotypes were analyzed; CD24 and CD133 double positive (CD24 + CD133 + ) cells were measured; and the levels of serum urea nitrogen (SUN) and serum creatinine (SCr) were detected. We found that CD24 + CD133 + RSCs were mobilized in WT ATN mice with the increased expression of Bmi-1; Bmi-1 deficiency led to increased tubular cast formation and necrosis, elevated levels of SUN and SCr, decreased tubular proliferation, and immobilized ratio of RSCs in ATN. These findings indicated that Bmi-1 played a critical role in the protection from ATN by maintaining mobilization of RSCs and would be a novel therapeutic target for preventing the progression of ATN.

  14. In vitro generation of renal tubular epithelial cells from fibroblasts: implications for precision and regenerative medicine in nephrology.

    Science.gov (United States)

    Wyatt, Christina M; Dubois, Nicole

    2017-02-01

    Prior efforts to generate renal epithelial cells in vitro have relied on pluripotent or bone marrow-derived mesenchymal stem cells. A recent publication in Nature Cell Biology describes the generation of induced tubular epithelial cells from fibroblasts, potentially offering a novel platform for personalized drug toxicity screening and in vitro disease modeling. This report serves as a promising proof of principle study and opens future research directions, including the optimization of the reprogramming process, efficient translation to adult human fibroblasts, and the generation of highly specific functional renal cell types. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  15. Selective Cannabinoid 2 Receptor Stimulation Reduces Tubular Epithelial Cell Damage after Renal Ischemia-Reperfusion Injury.

    Science.gov (United States)

    Pressly, Jeffrey D; Mustafa, Suni M; Adibi, Ammaar H; Alghamdi, Sahar; Pandey, Pankaj; Roy, Kuldeep K; Doerksen, Robert J; Moore, Bob M; Park, Frank

    2018-02-01

    Ischemia-reperfusion injury (IRI) is a common cause of acute kidney injury (AKI), which is an increasing problem in the clinic and has been associated with elevated rates of mortality. Therapies to treat AKI are currently not available, so identification of new targets that can be modulated to ameliorate renal damage upon diagnosis of AKI is essential. In this study, a novel cannabinoid receptor 2 (CB2) agonist, SMM-295 [3'-methyl-4-(2-(thiophen-2-yl)propan-2-yl)biphenyl-2,6-diol], was designed, synthesized, and tested in vitro and in silico. Molecular docking of SMM-295 into a CB2 active-state homology model showed that SMM-295 interacts well with key amino acids to stabilize the active state. In human embryonic kidney 293 cells, SMM-295 was capable of reducing cAMP production with 66-fold selectivity for CB2 versus cannabinoid receptor 1 and dose-dependently increased mitogen-activated protein kinase and Akt phosphorylation. In vivo testing of the CB2 agonist was performed using a mouse model of bilateral IRI, which is a common model to mimic human AKI, where SMM-295 was immediately administered upon reperfusion of the kidneys after the ischemia episode. Histologic damage assessment 48 hours after reperfusion demonstrated reduced tubular damage in the presence of SMM-295. This was consistent with reduced plasma markers of renal dysfunction (i.e., creatinine and neutrophil gelatinase-associated lipocalin) in SMM-295-treated mice. Mechanistically, kidneys treated with SMM-295 were shown to have elevated activation of Akt with reduced terminal deoxynucleotidyl transferase-mediated digoxigenin-deoxyuridine nick-end labeling (TUNEL)-positive cells compared with vehicle-treated kidneys after IRI. These data suggest that selective CB2 receptor activation could be a potential therapeutic target in the treatment of AKI. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  16. Amelioration of renal ischaemia-reperfusion injury by liposomal delivery of curcumin to renal tubular epithelial and antigen-presenting cells.

    Science.gov (United States)

    Rogers, N M; Stephenson, M D; Kitching, A R; Horowitz, J D; Coates, P T H

    2012-05-01

    Renal ischaemia-reperfusion (IR) injury is an inevitable consequence of renal transplantation, causing significant graft injury, increasing the risk of rejection and contributing to poor long-term graft outcome. Renal injury is mediated by cytokine and chemokine synthesis, inflammation and oxidative stress resulting from activation of the NF-κB pathway. We utilized liposomal incorporation of a potent inhibitor of the NF-κB pathway, curcumin, to target delivery to renal tubular epithelial and antigen-presenting cells. Liposomes containing curcumin were administered before bilateral renal ischaemia in C57/B6 mice, with subsequent reperfusion. Renal function was assessed from plasma levels of urea and creatinine, 4 and 24 h after reperfusion. Renal tissue was examined for NF-κB activity and oxidative stress (histology, immunostaining) and for apoptosis (TUNEL). Cytokines and chemokines were measured by RT-PCR and Western blotting. Liposomal curcumin significantly improved serum creatinine, reduced histological injury and cellular apoptosis and lowered Toll-like receptor-4, heat shock protein-70 and TNF-α mRNA expression. Liposomal curcumin also reduced neutrophil infiltration and diminished inflammatory chemokine expression. Curcumin liposomes reduced intracellular superoxide generation and increased superoxide dismutase levels, decreased inducible NOS mRNA expression and 3-nitrotyrosine staining consistent with limitations in nitrosative stress and inhibited renal tubular mRNA and protein expression of thioredoxin-interacting protein. These actions of curcumin were mediated by inhibition of NF-κB, MAPK and phospho-S6 ribosomal protein. Liposomal delivery of curcumin promoted effective, targeted delivery of this non-toxic compound that provided cytoprotection via anti-inflammatory and multiple antioxidant mechanisms following renal IR injury. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

  17. Ceramide-Induced Apoptosis in Renal Tubular Cells: A Role of Mitochondria and Sphingosine-1-Phoshate

    Science.gov (United States)

    Ueda, Norishi

    2015-01-01

    Ceramide is synthesized upon stimuli, and induces apoptosis in renal tubular cells (RTCs). Sphingosine-1 phosphate (S1P) functions as a survival factor. Thus, the balance of ceramide/S1P determines ceramide-induced apoptosis. Mitochondria play a key role for ceramide-induced apoptosis by altered mitochondrial outer membrane permeability (MOMP). Ceramide enhances oligomerization of pro-apoptotic Bcl-2 family proteins, ceramide channel, and reduces anti-apoptotic Bcl-2 proteins in the MOM. This process alters MOMP, resulting in generation of reactive oxygen species (ROS), cytochrome C release into the cytosol, caspase activation, and apoptosis. Ceramide regulates apoptosis through mitogen-activated protein kinases (MAPKs)-dependent and -independent pathways. Conversely, MAPKs alter ceramide generation by regulating the enzymes involving ceramide metabolism, affecting ceramide-induced apoptosis. Crosstalk between Bcl-2 family proteins, ROS, and many signaling pathways regulates ceramide-induced apoptosis. Growth factors rescue ceramide-induced apoptosis by regulating the enzymes involving ceramide metabolism, S1P, and signaling pathways including MAPKs. This article reviews evidence supporting a role of ceramide for apoptosis and discusses a role of mitochondria, including MOMP, Bcl-2 family proteins, ROS, and signaling pathways, and crosstalk between these factors in the regulation of ceramide-induced apoptosis of RTCs. A balancing role between ceramide and S1P and the strategy for preventing ceramide-induced apoptosis by growth factors are also discussed. PMID:25751724

  18. Involvement of endoplasmic reticulum stress in albuminuria induced inflammasome activation in renal proximal tubular cells.

    Directory of Open Access Journals (Sweden)

    Li Fang

    Full Text Available Albuminuria contributes to the progression of tubulointerstitial fibrosis. Although it has been demonstrated that ongoing albuminuria leads to tubular injury manifested by the overexpression of numerous proinflammatory cytokines, the mechanism remains largely unknown. In this study, we found that the inflammasome activation which has been recognized as one of the cornerstones of intracellular surveillance system was associated with the severity of albuminuria in the renal biopsies specimens. In vitro, bovine serum albumin (BSA could also induce the activation of NLRP3 inflammasome in the cultured kidney epithelial cells (NRK-52E. Since there was a significant overlap of NLRP3 with the ER marker calreticulin, the ER stress provoked by BSA seemed to play a crucial role in the activation of inflammasome. Here, we demonstrated that the chemical chaperone taurine-conjugated ursodeoxycholic acid (TUDCA which was proved to be an enhancer for the adaptive capacity of ER could attenuate the inflammasome activation induced by albuminuria not only in vitro but also in diabetic nephropathy. Taken together, these data suggested that ER stress seemed to play an important role in albuminuria-induced inflammasome activation, elimination of ER stress via TUDCA might hold promise as a novel avenue for preventing inflammasome activation ameliorating kidney epithelial cells injury induced by albuminuria.

  19. Expression of Nestin, Vimentin, and NCAM by Renal Interstitial Cells after Ischemic Tubular Injury

    Directory of Open Access Journals (Sweden)

    David Vansthertem

    2010-01-01

    Full Text Available This work explores the distribution of various markers expressed by interstitial cells in rat kidneys after ischemic injury (35 minutes during regeneration of S3 tubules of outer stripe of outer medulla (OSOM. Groups of experimental animals (n=4 were sacrificed every two hours during the first 24 hours post-ischemia as well as 2, 3, 7, 14 days post-ischemia. The occurrence of lineage markers was analyzed on kidney sections by immunohistochemistry and morphometry during the process of tubular regeneration. In postischemic kidneys, interstitial cell proliferation, assessed by 5-bromo-2′-deoxyuridine (BrdU and Proliferating Cell Nuclear Antigen (PCNA labeling, was prominent in outer medulla and reach a maximum between 24 and 72 hours after reperfusion. This population was characterized by the coexpression of vimentin and nestin. The density of -Neural Cell Adhesion Molecule (NCAM positive interstitial cells increased transiently (18–72 hours in the vicinity of altered tubules. We have also localized a small population of α-Smooth Muscle Actin (SMA-positive cells confined to chronically altered areas and characterized by a small proliferative index. In conclusion, we observed in the postischemic kidney a marked proliferation of interstitial cells that underwent transient phenotypical modifications. These interstitial cells could be implicated in processes leading to renal fibrosis.

  20. Lack of passive transfer of renal tubulointerstitial disease by serum or monoclonal antibody specific for renal tubular antigens in the mouse.

    Science.gov (United States)

    Evans, B D; Dilwith, R L; Balaban, S L; Rudofsky, U H

    1988-01-01

    Mice immunized with rabbit renal basement membranes form autoantibodies to their kidney glomerular and tubular basement membranes (GBM/TBM). Development of renal tubular disease (RTD) consists of deposition of autoantibodies along the GBM/TBM with the inter- and intratubular accumulation of lymphocytes and macrophages and destruction of the TBM. Transfer of this disease in mice with either serum or monoclonal antibodies, however, has been difficult to demonstrate and, therefore, attempts were made to confirm a report that RTD is passively transferred by anti-TBM autoantibodies. Using the revised protocol in this later report, we found that 12 weeks after transfer autoantibodies were deposited along the GBM and/or TBM of the recipients, yet RTD was not observed. Although qualitative and quantitative characteristics of the antibody may play a role in the pathogenesis in the murine model of RTD, we could not obtain evidence to support and confirm this study.

  1. Albumin stimulates renal tubular inflammation through an HSP70-TLR4 axis in mice with early diabetic nephropathy

    Science.gov (United States)

    Jheng, Huei-Fen; Tsai, Pei-Jane; Chuang, Yi-Lun; Shen, Yi-Ting; Tai, Ting-An; Chen, Wen-Chung; Chou, Chuan-Kai; Ho, Li-Chun; Tang, Ming-Jer; Lai, Kuei-Tai A.; Sung, Junne-Ming; Tsai, Yau-Sheng

    2015-01-01

    ABSTRACT Increased urinary albumin excretion is not simply an aftermath of glomerular injury, but is also involved in the progression of diabetic nephropathy (DN). Whereas Toll-like receptors (TLRs) are incriminated in the renal inflammation of DN, whether and how albumin is involved in the TLR-related renal inflammatory response remains to be clarified. Here, we showed that both TLR2 and TLR4, one of their putative endogenous ligands [heat shock protein 70 (HSP70)] and nuclear factor-κB promoter activity were markedly elevated in the kidneys of diabetic mice. A deficiency of TLR4 but not of TLR2 alleviated albuminuria, tubulointerstitial fibrosis and inflammation induced by diabetes. The protection against renal injury in diabetic Tlr4−/− mice was associated with reduced tubular injuries and preserved cubilin levels, rather than amelioration of glomerular lesions. In vitro studies revealed that albumin, a stronger inducer than high glucose (HG), induced the release of HSP70 from proximal tubular cells. HSP70 blockade ameliorated albumin-induced inflammatory mediators. HSP70 triggered the production of inflammatory mediators in a TLR4-dependent manner. Moreover, HSP70 inhibition in vivo ameliorated diabetes-induced albuminuria, inflammatory response and tubular injury. Finally, we found that individuals with DN had higher levels of TLR4 and HSP70 in the dilated tubules than non-diabetic controls. Thus, activation of the HSP70-TLR4 axis, stimulated at least in part by albumin, in the tubular cell is a newly identified mechanism associated with induction of tubulointerstitial inflammation and aggravation of pre-existing microalbuminuria in the progression of DN. PMID:26398934

  2. Ex vivo hyperpolarized MR spectroscopy on isolated renal tubular cells: A novel technique for cell energy phenotyping.

    Science.gov (United States)

    Juul, Troels; Palm, Fredrik; Nielsen, Per Mose; Bertelsen, Lotte Bonde; Laustsen, Christoffer

    2017-08-01

    It has been demonstrated that hyperpolarized 13 C MR is a useful tool to study cultured cells. However, cells in culture can alter phenotype, which raises concerns regarding the in vivo significance of such findings. Here we investigate if metabolic phenotyping using hyperpolarized 13 C MR is suitable for cells isolated from kidney tissue, without prior cell culture. Isolation of tubular cells from freshly excised kidney tissue and treatment with either ouabain or antimycin A was investigated with hyperpolarized MR spectroscopy on a 9.4 Tesla preclinical imaging system. Isolation of tubular cells from less than 2 g of kidney tissue generally resulted in more than 10 million live tubular cells. This amount of cells was enough to yield robust signals from the conversion of 13 C-pyruvate to lactate, bicarbonate and alanine, demonstrating that metabolic flux by means of both anaerobic and aerobic pathways can be quantified using this technique. Ex vivo metabolic phenotyping using hyperpolarized 13 C MR in a preclinical system is a useful technique to study energy metabolism in freshly isolated renal tubular cells. This technique has the potential to advance our understanding of both normal cell physiology as well as pathological processes contributing to kidney disease. Magn Reson Med 78:457-461, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  3. Sirt1 protects against oxidative stress-induced renal tubular cell apoptosis by the bidirectional regulation of catalase expression

    International Nuclear Information System (INIS)

    Hasegawa, Kazuhiro; Wakino, Shu; Yoshioka, Kyoko; Tatematsu, Satoru; Hara, Yoshikazu; Minakuchi, Hitoshi; Washida, Naoki; Tokuyama, Hirobumi; Hayashi, Koichi; Itoh, Hiroshi

    2008-01-01

    NAD + -dependent protein deacetylase Sirt1 regulates cellular apoptosis. We examined the role of Sirt1 in renal tubular cell apoptosis by using HK-2 cells, proximal tubular cell lines with or without reactive oxygen species (ROS), H 2 O 2 . Without any ROS, Sirt1 inhibitors enhanced apoptosis and the expression of ROS scavenger, catalase, and Sirt1 overexpression downregulated catalase. When apoptosis was induced with H 2 O 2 , Sirt1 was upregulated with the concomitant increase in catalase expression. Sirt1 overexpression rescued H 2 O 2 -induced apoptosis through the upregulation of catalase. H 2 O 2 induced the nuclear accumulation of forkhead transcription factor, FoxO3a and the gene silencing of FoxO3a enhanced H 2 O 2 -induced apoptosis. In conclusion, endogenous Sirt1 maintains cell survival by regulating catalase expression and by preventing the depletion of ROS required for cell survival. In contrast, excess ROS upregulates Sirt1, which activates FoxO3a and catalase leading to rescuing apoptosis. Thus, Sirt1 constitutes a determinant of renal tubular cell apoptosis by regulating cellular ROS levels

  4. THE FAILURE OF CHLOROFORM ADMINISTERED IN THE DRINKING WATER TO INDUCE RENAL TUBULAR CELL NEOPLASIA IN MALE F344/N RATS

    Science.gov (United States)

    The failure of chloroform administered in drinking water to induce renal tubular cell neoplasia in male F344/N rats Chloroform (TCM) has been demonstrated to be a renal carcinogen in the male Osborne-Mendel rat when administered either by corn oil gavage or in drin...

  5. The entire miR-200 seed family is strongly deregulated in clear cell renal cell cancer compared to the proximal tubular epithelial cells of the kidney

    NARCIS (Netherlands)

    Duns, Gerben; van den Berg, Anke; van Dijk, Marcory C. R. F.; van Duivenbode, Inge; Giezen, Cor; Kluiver, Joost; van Goor, Harry; Hofstra, Robert M. W.; van den Berg, Eva; Kok, Klaas

    Despite numerous studies reporting deregulated microRNA (miRNA) and gene expression patterns in clear cell renal cell carcinoma (ccRCC), no direct comparisons have been made to its presumed normal counterpart: the renal proximal tubular epithelial cells (PTECs). The aim of this study was to

  6. Distal renal tubular acidosis as a cause of osteomalacia in a patient with primary Sjögren's syndrome

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    Jovelić Aleksandra

    2005-01-01

    Full Text Available Background. One half of the patients with primary Sjögren’s syndrome has extraglandular manifestations, including renal involvement. The most frequent renal lesion is tubulo-interstitial nephritis, which manifests clinically as distal tubular acidosis and may result in the development of osteomalacia. Case report. In a 29 - year-old female patient, with bilateral nephrolithiasis, the diagnosis of primary Sjögren’s syndrome, tubulo-interstitial nephritis, distal renal tubular acidosis, and hypokalemia were established. She was treated for hypokalemia. Two years later she developed bone pains and muscle weakness, she wasn’t able to walk, her proximal muscles and pelvic bones were painful, with radiological signs of pelvic bones osteopenia and pubic bones fractures. The diagnosis of osteomalacia was established and the treatment started with Schol’s solution, vitamin D and calcium. In the following two months, acidosis was corrected, and the patient started walking. Conclusion. In our patient with primary Sjögren’s syndrome and interstitial nephritis, osteomalacia was a result of the long time decompensate acidosis, so the correction of acidosis, and the supplementation of vitamin D and calcium were the integral part of the therapy.

  7. Sodium bicarbonate cotransporter NBCe2 gene variants increase sodium and bicarbonate transport in human renal proximal tubule cells.

    Science.gov (United States)

    Gildea, John J; Xu, Peng; Kemp, Brandon A; Carlson, Julia M; Tran, Hanh T; Bigler Wang, Dora; Langouët-Astrié, Christophe J; McGrath, Helen E; Carey, Robert M; Jose, Pedro A; Felder, Robin A

    2018-01-01

    Salt sensitivity of blood pressure affects >30% of the hypertensive and >15% of the normotensive population. Variants of the electrogenic sodium bicarbonate cotransporter NBCe2 gene, SLC4A5, are associated with increased blood pressure in several ethnic groups. SLC4A5 variants are also highly associated with salt sensitivity, independent of hypertension. However, little is known about how NBCe2 contributes to salt sensitivity, although NBCe2 regulates renal tubular sodium bicarbonate transport. We hypothesized that SLC4A5 rs10177833 and rs7571842 increase NBCe2 expression and human renal proximal tubule cell (hRPTC) sodium transport and may be a cause of salt sensitivity of blood pressure. To characterize the hRPTC ion transport of wild-type (WT) and homozygous variants (HV) of SLC4A5. The expressions of NBCe2 mRNA and protein were not different between hRPTCs carrying WT or HV SLC4A5 before or after dopaminergic or angiotensin (II and III) stimulation. However, luminal to basolateral sodium transport, NHE3 protein, and Cl-/HCO3- exchanger activity in hRPTCs were higher in HV than WT SLC4A5. Increasing intracellular sodium enhanced the apical location of NBCe2 in HV hRPTCs (4.24±0.35% to 11.06±1.72% (P<0.05, N = 3, 2-way ANOVA, Holm-Sidak test)) as determined by Total Internal Reflection Fluorescence Microscopy (TIRFM). In hRPTCs isolated from kidney tissue, increasing intracellular sodium enhanced bicarbonate-dependent pH recovery rate and increased NBCe2 mRNA and protein expressions to a greater extent in HV than WT SLC4A5 (+38.00±6.23% vs HV normal salt (P<0.01, N = 4, 2-way ANOVA, Holm-Sidak test)). In hRPTCs isolated from freshly voided urine, bicarbonate-dependent pH recovery was also faster in those from salt-sensitive and carriers of HV SLC4A5 than from salt-resistant and carriers of WT SLC4A5. The faster NBCe2-specific bicarbonate-dependent pH recovery rate in HV SCL4A5 was normalized by SLC4A5- but not SLC4A4-shRNA. The binding of purified hepatocyte

  8. Abnormal distal renal tubular acidification in patients with low bone mass: prevalence and impact of alkali treatment.

    Science.gov (United States)

    Sromicki, Jerzy Jan; Hess, Bernhard

    2017-06-01

    Chronic acid retention is known to promote bone dissolution. In this study, 23 % of patients with osteopenia/osteoporosis were diagnosed with abnormal distal renal tubular acidification (dRTA), a kidney dysfunction leading to chronic acid retention. Treating those patients with alkali-therapy shows improvement in bone density. To evaluate the prevalence of abnormal distal renal tubular acidification in patients with low bone mass (LBM) and the impact of additional alkali treatment on bone density in patients with concomitant LBM and dRTA,183 patients referred for metabolic evaluation of densitometrically proven low bone mass were screened for abnormal distal renal tubular acidification between 2006 and 2013. In all LBM urine pH (U-pH) was measured in the 2nd morning urines after 12 h of fasting. If U-pH was ≥5.80, LBM underwent a 1-day ammonium chloride loading, and U-pH was remeasured the next morning. If U-pH after acid loading did not drop below 5.45, patients were diagnosed with abnormal distal renal tubular acidification. Normal values were obtained from 21 healthy controls. All LBM with dRTA were recommended alkali citrate in addition to conventional therapy of LBM, and follow-up DXAs were obtained until 2014. 85 LBM underwent NH 4 Cl loading. 42 LBM patients were diagnosed with incomplete dRTA (idRTA; prevalence 23.0 %). During follow-up (1.6-8 years) of idRTA-LBM patients, subjects adhering to alkali treatment tended to improve BMD at all sites measured, whereas BMD of non-adherent idRTA patients worsened/remained unchanged. (1) About one out of four patients with osteopenia/osteoporosis has idRTA. (2) Upon NH 4 Cl loading, idRTA patients do not lower urine pH normally, but show signs of increased acid-buffering by bone dissolution. (3) In idRTA patients with low bone mass on conventional therapy, additional long-term alkali treatment improves bone mass at lumbar spine and potentially at other bone sites. (4) All patients with low bone mass undergoing

  9. Failure to thrive and nephrocalcinosis due to distal renal tubular acidosis: A rare presentation of pediatric lupus nephritis.

    Science.gov (United States)

    Nandi, Madhumita; Das, Mrinal Kanti; Nandi, Sukanta

    2016-01-01

    A 9-year-old female child was initially diagnosed of having nephrocalcinosis with distal renal tubular acidosis (dRTA) while investigating for short stature. She later on developed features of nephrotic syndrome (NS) while on treatment for RTA. Investigation for the cause of NS revealed very strong serological evidence in favor of systemic lupus erythematosus (SLE). Histopathological confirmation could not be done due to bilateral severely contracted kidneys. There are a few case reports of dRTA as the presentation of SLE, but nephrocalcinosis with dRTA with subsequent manifestation of SLE has hitherto not been reported in literature.

  10. Evaluation of the potential interaction between tofacitinib and drugs that undergo renal tubular secretion using metformin, an in vivo marker of renal organic cation transporter 2.

    Science.gov (United States)

    Klamerus, Karen J; Alvey, Christine; Li, Lei; Feng, Bo; Wang, Rong; Kaplan, Irina; Shi, Haihong; Dowty, Martin E; Krishnaswami, Sriram

    2014-11-01

    Tofacitinib is a novel, oral Janus kinase inhibitor. The potential for drug-drug interactions (DDIs) between tofacitinib and drugs that undergo renal tubular secretion was evaluated using metformin as a probe transporter substrate, and genotyping for organic cation transporter (OCT) 1, OCT2 and multidrug and toxin extrusion 1 polymorphisms. Twenty-four healthy male subjects completed this open-label, fixed-sequence study. Subjects were administered a single oral metformin 500 mg dose on Days 1 and 4, and multiple oral tofacitinib 30 mg twice daily doses on Days 2, 3, and 4. Subjects underwent serial blood and urine samplings (Days 1 and 4) to estimate metformin pharmacokinetics. A single blood sample for tofacitinib was collected 2 hours after the morning dose (Day 4). The 90% confidence intervals for the ratios of maximum plasma concentration, area under the curve and renal clearance of metformin, with and without tofacitinib, were contained within the 80-125% acceptance range commonly used to establish a lack of DDI. No deaths, serious adverse events (AEs), severe AEs or discontinuations due to AEs were reported. The study confirms tofacitinib is unlikely to impact the pharmacokinetics of drugs that undergo renal tubular secretion, and concurs with its weak in vitro OCT2 inhibitory profile. © 2014, The American College of Clinical Pharmacology.

  11. Proximal tubular hypertrophy and enlarged glomerular and proximal tubular urinary space in obese subjects with proteinuria.

    Directory of Open Access Journals (Sweden)

    Ana Tobar

    Full Text Available BACKGROUND: Obesity is associated with glomerular hyperfiltration, increased proximal tubular sodium reabsorption, glomerular enlargement and renal hypertrophy. A single experimental study reported an increased glomerular urinary space in obese dogs. Whether proximal tubular volume is increased in obese subjects and whether their glomerular and tubular urinary spaces are enlarged is unknown. OBJECTIVE: To determine whether proximal tubules and glomerular and tubular urinary space are enlarged in obese subjects with proteinuria and glomerular hyperfiltration. METHODS: Kidney biopsies from 11 non-diabetic obese with proteinuria and 14 non-diabetic lean patients with a creatinine clearance above 50 ml/min and with mild or no interstitial fibrosis were retrospectively analyzed using morphometric methods. The cross-sectional area of the proximal tubular epithelium and lumen, the volume of the glomerular tuft and of Bowman's space and the nuclei number per tubular profile were estimated. RESULTS: Creatinine clearance was higher in the obese than in the lean group (P=0.03. Proteinuria was similarly increased in both groups. Compared to the lean group, the obese group displayed a 104% higher glomerular tuft volume (P=0.001, a 94% higher Bowman's space volume (P=0.003, a 33% higher cross-sectional area of the proximal tubular epithelium (P=0.02 and a 54% higher cross-sectional area of the proximal tubular lumen (P=0.01. The nuclei number per proximal tubular profile was similar in both groups, suggesting that the increase in tubular volume is due to hypertrophy and not to hyperplasia. CONCLUSIONS: Obesity-related glomerular hyperfiltration is associated with proximal tubular epithelial hypertrophy and increased glomerular and tubular urinary space volume in subjects with proteinuria. The expanded glomerular and urinary space is probably a direct consequence of glomerular hyperfiltration. These effects may be involved in the pathogenesis of obesity

  12. Specific estrogen-induced cell proliferation of cultured Syrian hamster renal proximal tubular cells in serum-free chemically defined media

    International Nuclear Information System (INIS)

    Oberley, T.D.; Lauchner, L.J.; Pugh, T.D.; Gonzalez, A.; Goldfarb, S.; Li, S.A.; Li, J.J.

    1989-01-01

    It has long been recognized that the renal proximal tubular epithelium of the hamster is a bona fide estrogen target tissue. The effect of estrogens on the growth of proximal tubule cell explants and dissociated single cells derived from these explant outgrowths has been studied in culture. Renal tubular cells were grown on a PF-HR-9 basement membrane under serum-free chemically defined culture conditions. At 7-14 days in culture, cell number was enhanced 3-fold in the presence of either 17β-estradiol or diethylstilbestrol. A similar 3-fold increase in cell number was also seen at 1 nM 17β-estradiol in subcultured dissociated single tubular cells derived from hamster renal tubular explant outgrowths at 21 days in culture. Concomitant exposure of tamoxifen at 3-fold molar excess in culture completely abolished the increase in cell number seen with 17β-estradiol. The proliferation effect of estrogens on proximal tubular cell growth appears to be species specific since 17β-estradiol did not alter the growth of either rat or guinea pig proximal tubules in culture. In addition, at 7-10 days in culture in the presence of 17β-estradiol, [ 3 H]thymidine labeling of hamster tubular cells was enhanced 3-fold. These results clearly indicate that estrogens can directly induce primary epithelial cell proliferation at physiologic concentrations and provide strong additional evidence for an important hormonal role in the neoplastic transformation of the hamster kidney

  13. Lovastatin prevents cisplatin-induced activation of pro-apoptotic DNA damage response (DDR) of renal tubular epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Krüger, Katharina; Ziegler, Verena; Hartmann, Christina; Henninger, Christian [Institute of Toxicology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf (Germany); Thomale, Jürgen [Institute of Cell Biology, University Duisburg-Essen, 45122 Essen (Germany); Schupp, Nicole [Institute of Toxicology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf (Germany); Fritz, Gerhard, E-mail: fritz@uni-duesseldorf.de [Institute of Toxicology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf (Germany)

    2016-02-01

    The platinating agent cisplatin (CisPt) is commonly used in the therapy of various types of solid tumors. The anticancer efficacy of CisPt largely depends on the formation of bivalent DNA intrastrand crosslinks, which stimulate mechanisms of the DNA damage response (DDR), thereby triggering checkpoint activation, gene expression and cell death. The clinically most relevant adverse effect associated with CisPt treatment is nephrotoxicity that results from damage to renal tubular epithelial cells. Here, we addressed the question whether the HMG-CoA-reductase inhibitor lovastatin affects the DDR of renal cells by employing rat renal proximal tubular epithelial (NRK-52E) cells as in vitro model. The data show that lovastatin has extensive inhibitory effects on CisPt-stimulated DDR of NRK-52E cells as reflected on the levels of phosphorylated ATM, Chk1, Chk2, p53 and Kap1. Mitigation of CisPt-induced DDR by lovastatin was independent of the formation of DNA damage as demonstrated by (i) the analysis of Pt-(GpG) intrastrand crosslink formation by Southwestern blot analyses and (ii) the generation of DNA strand breaks as analyzed on the level of nuclear γH2AX foci and employing the alkaline comet assay. Lovastatin protected NRK-52E cells from the cytotoxicity of high CisPt doses as shown by measuring cell viability, cellular impedance and flow cytometry-based analyses of cell death. Importantly, the statin also reduced the level of kidney DNA damage and apoptosis triggered by CisPt treatment of mice. The data show that the lipid-lowering drug lovastatin extensively counteracts pro-apoptotic signal mechanisms of the DDR of tubular epithelial cells following CisPt injury. - Highlights: • Lovastatin blocks ATM/ATR-regulated DDR of tubular cells following CisPt treatment. • Lovastatin attenuates CisPt-induced activation of protein kinase ATM in vitro. • Statin-mediated DDR inhibition is independent of initial DNA damage formation. • Statin-mediated blockage of Cis

  14. Lovastatin prevents cisplatin-induced activation of pro-apoptotic DNA damage response (DDR) of renal tubular epithelial cells

    International Nuclear Information System (INIS)

    Krüger, Katharina; Ziegler, Verena; Hartmann, Christina; Henninger, Christian; Thomale, Jürgen; Schupp, Nicole; Fritz, Gerhard

    2016-01-01

    The platinating agent cisplatin (CisPt) is commonly used in the therapy of various types of solid tumors. The anticancer efficacy of CisPt largely depends on the formation of bivalent DNA intrastrand crosslinks, which stimulate mechanisms of the DNA damage response (DDR), thereby triggering checkpoint activation, gene expression and cell death. The clinically most relevant adverse effect associated with CisPt treatment is nephrotoxicity that results from damage to renal tubular epithelial cells. Here, we addressed the question whether the HMG-CoA-reductase inhibitor lovastatin affects the DDR of renal cells by employing rat renal proximal tubular epithelial (NRK-52E) cells as in vitro model. The data show that lovastatin has extensive inhibitory effects on CisPt-stimulated DDR of NRK-52E cells as reflected on the levels of phosphorylated ATM, Chk1, Chk2, p53 and Kap1. Mitigation of CisPt-induced DDR by lovastatin was independent of the formation of DNA damage as demonstrated by (i) the analysis of Pt-(GpG) intrastrand crosslink formation by Southwestern blot analyses and (ii) the generation of DNA strand breaks as analyzed on the level of nuclear γH2AX foci and employing the alkaline comet assay. Lovastatin protected NRK-52E cells from the cytotoxicity of high CisPt doses as shown by measuring cell viability, cellular impedance and flow cytometry-based analyses of cell death. Importantly, the statin also reduced the level of kidney DNA damage and apoptosis triggered by CisPt treatment of mice. The data show that the lipid-lowering drug lovastatin extensively counteracts pro-apoptotic signal mechanisms of the DDR of tubular epithelial cells following CisPt injury. - Highlights: • Lovastatin blocks ATM/ATR-regulated DDR of tubular cells following CisPt treatment. • Lovastatin attenuates CisPt-induced activation of protein kinase ATM in vitro. • Statin-mediated DDR inhibition is independent of initial DNA damage formation. • Statin-mediated blockage of Cis

  15. Attenuation of oxidative stress and inflammation by gravinol in high glucose-exposed renal tubular epithelial cells

    International Nuclear Information System (INIS)

    Kim, You Jung; Kim, Young Ae; Yokozawa, Takako

    2010-01-01

    Gravinol, a proanthocyanidin from grape seeds, has polyphenolic properties with powerful anti-oxidative effects. Although, increasing evidence strongly suggests that polyphenolic antioxidants suppress diabetic nephropathy that is causally associated with oxidative stress and inflammation, gravinol's protective action against diabetic nephropathy has not been fully explored to date. In the current study, we investigated the protective action of gravinol against oxidative stress and inflammation using the experimental diabetic nephropathy cell model, high glucose-exposed renal tubular epithelial cells. To elucidate the underlying actions of gravinol, several oxidative and inflammatory markers were estimated. Included are measurements of lipid peroxidation, total reactive species (RS), superoxide (·O 2 ), nitric oxide (NO·), and peroxynitrite (ONOO - ), as well as nuclear factor-kappa B (NF-κB) nuclear translocation. Results indicate that gravinol had a potent inhibitory action against lipid peroxidation, total RS, ·O 2 , NO·, ONOO - , the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio and more importantly, against NF-κB nuclear translocation. We propose that gravinol's strong protective effect against high glucose-induced renal tubular epithelial cell damage attenuates diabetic nephropathy by suppressing oxidative stress and inflammation.

  16. TWEAK activates the non-canonical NFkappaB pathway in murine renal tubular cells: modulation of CCL21.

    Directory of Open Access Journals (Sweden)

    Ana B Sanz

    2010-01-01

    Full Text Available TWEAK is a member of the TNF superfamily of cytokines that contribute to kidney tubulointerstitial injury. It has previously been reported that TWEAK induces transient nuclear translocation of RelA and expression of RelA-dependent cytokines in renal tubular cells. Additionally, TWEAK induced long-lasting NFkappaB activation suggestive of engagement of the non-canonical NFkappaB pathway. We now explore TWEAK-induced activation of NFkappaB2 and RelB, as well as expression of CCL21, a T-cell chemotactic factor, in cultured murine tubular epithelial cells and in healthy kidneys in vivo. In cultured tubular cells, TWEAK and TNFalpha activated different DNA-binding NFkappaB complexes. TWEAK-induced sustained NFkappaB activation was associated with NFkappaB2 p100 processing to p52 via proteasome and nuclear translocation and DNA-binding of p52 and RelB. TWEAK, but not TNFalpha used as control, induced a delayed increase in CCL21a mRNA (3.5+/-1.22-fold over control and CCL21 protein (2.5+/-0.8-fold over control, which was prevented by inhibition of the proteasome, or siRNA targeting of NIK or RelB, but not by RelA inhibition with parthenolide. A second NFkappaB2-dependent chemokine, CCL19, was upregulates by TWEAK, but not by TNFalpha. However, both cytokines promoted chemokine RANTES expression (3-fold mRNA at 24 h. In vivo, TWEAK induced nuclear NFkappaB2 and RelB translocation and CCL21a mRNA (1.5+/-0.3-fold over control and CCL21 protein (1.6+/-0.5-fold over control expression in normal kidney. Increased tubular nuclear RelB and tubular CCL21 expression in acute kidney injury were decreased by neutralization (2+/-0.9 vs 1.3+/-0.6-fold over healthy control or deficiency of TWEAK (2+/-0.9 vs 0.8+/-0.6-fold over healthy control. Moreover, anti-TWEAK treatment prevented the recruitment of T cells to the kidney in this model (4.1+/-1.4 vs 1.8+/-1-fold over healthy control. Our results thus identify TWEAK as a regulator of non-canonical NFkappa

  17. Dragon (Repulsive Guidance Molecule RGMb) Inhibits E-cadherin Expression and Induces Apoptosis in Renal Tubular Epithelial Cells*

    Science.gov (United States)

    Liu, Wenjing; Li, Xiaoling; Zhao, Yueshui; Meng, Xiao-Ming; Wan, Chao; Yang, Baoxue; Lan, Hui-Yao; Lin, Herbert Y.; Xia, Yin

    2013-01-01

    Dragon is one of the three members of the repulsive guidance molecule (RGM) family, i.e. RGMa, RGMb (Dragon), and RGMc (hemojuvelin). We previously identified the RGM members as bone morphogenetic protein (BMP) co-receptors that enhance BMP signaling. Our previous studies found that Dragon is highly expressed in the tubular epithelial cells of mouse kidneys. However, the roles of Dragon in renal epithelial cells are yet to be defined. We now show that overexpression of Dragon increased cell death induced by hypoxia in association with increased cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 levels in mouse inner medullary collecting duct (IMCD3) cells. Dragon also inhibited E-cadherin expression but did not affect epithelial-to-mesenchymal transition induced by TGF-β in IMCD3 cells. Previous studies suggest that the three RGM members can function as ligands for the receptor neogenin. Interestingly, our present study demonstrates that the Dragon actions on apoptosis and E-cadherin expression in IMCD3 cells were mediated by the neogenin receptor but not through the BMP pathway. Dragon expression in the kidney was up-regulated by unilateral ureteral obstruction in mice. Compared with wild-type mice, heterozygous Dragon knock-out mice exhibited 45–66% reduction in Dragon mRNA expression, decreased epithelial apoptosis, and increased tubular E-cadherin expression and had attenuated tubular injury after unilateral ureteral obstruction. Our results suggest that Dragon may impair tubular epithelial integrity and induce epithelial apoptosis both in vitro and in vivo. PMID:24052264

  18. Dragon (repulsive guidance molecule RGMb) inhibits E-cadherin expression and induces apoptosis in renal tubular epithelial cells.

    Science.gov (United States)

    Liu, Wenjing; Li, Xiaoling; Zhao, Yueshui; Meng, Xiao-Ming; Wan, Chao; Yang, Baoxue; Lan, Hui-Yao; Lin, Herbert Y; Xia, Yin

    2013-11-01

    Dragon is one of the three members of the repulsive guidance molecule (RGM) family, i.e. RGMa, RGMb (Dragon), and RGMc (hemojuvelin). We previously identified the RGM members as bone morphogenetic protein (BMP) co-receptors that enhance BMP signaling. Our previous studies found that Dragon is highly expressed in the tubular epithelial cells of mouse kidneys. However, the roles of Dragon in renal epithelial cells are yet to be defined. We now show that overexpression of Dragon increased cell death induced by hypoxia in association with increased cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 levels in mouse inner medullary collecting duct (IMCD3) cells. Dragon also inhibited E-cadherin expression but did not affect epithelial-to-mesenchymal transition induced by TGF-β in IMCD3 cells. Previous studies suggest that the three RGM members can function as ligands for the receptor neogenin. Interestingly, our present study demonstrates that the Dragon actions on apoptosis and E-cadherin expression in IMCD3 cells were mediated by the neogenin receptor but not through the BMP pathway. Dragon expression in the kidney was up-regulated by unilateral ureteral obstruction in mice. Compared with wild-type mice, heterozygous Dragon knock-out mice exhibited 45-66% reduction in Dragon mRNA expression, decreased epithelial apoptosis, and increased tubular E-cadherin expression and had attenuated tubular injury after unilateral ureteral obstruction. Our results suggest that Dragon may impair tubular epithelial integrity and induce epithelial apoptosis both in vitro and in vivo.

  19. Direct effect of methylprednisolone on renal sodium and water transport via the principal cells in the kidney

    DEFF Research Database (Denmark)

    Lauridsen, Thomas G; Vase, Henrik; Bech, Jesper N

    2010-01-01

    Glucocorticoids influence renal concentrating and diluting ability. We tested the hypothesis that methylprednisolone treatment increased renal water and sodium absorption by increased absorption via the aquaporin-2 (AQP2) water channels and the epithelial sodium channels (ENaCs) respectively....

  20. Effect of tolvaptan on renal water and sodium excretion and blood pressure during nitric oxide inhibition

    DEFF Research Database (Denmark)

    Therwani, Safa Al; Rosenbæk, Jeppe Bakkestrøm; Mose, Frank Holden

    2017-01-01

    BACKGROUND: Tolvaptan is a selective vasopressin receptor antagonist. Nitric Oxide (NO) promotes renal water and sodium excretion, but the effect is unknown in the nephron's principal cells. In a dose-response study, we measured the effect of tolvaptan on renal handling of water and sodium....... CONCLUSIONS: During baseline, fractional excretion of sodium was unchanged. During tolvaptan with NO-inhibition, renal water excretion was reduced dose dependently, and renal sodium excretion was reduced unrelated to the dose, partly via an AVP dependent mechanism. Thus, tolvaptan antagonized the reduction...... in renal water and sodium excretion during NO-inhibition. Most likely, the lack of decrease in AQP2 excretion by tolvaptan could be attributed to a counteracting effect of the high level of p-AVP....

  1. The effect of RAAS blockade on markers of renal tubular damage in diabetic nephropathy

    DEFF Research Database (Denmark)

    Nielsen, Stine; Rossing, Kasper; Hess, Georg

    2012-01-01

    Blockade of the renin-angiotensin-aldosterone system (RAAS) affects both the glomerulus and tubules. We aimed to investigate the effect of irbesartan on the tubular markers: urinary (u) neutrophil gelatinase associated protein (NGAL), Kidney injury molecule 1 (KIM1) and liver-fatty acid......-binding protein (LFABP)....

  2. Improved Structure and Function in Autosomal Recessive Polycystic Rat Kidneys with Renal Tubular Cell Therapy.

    Science.gov (United States)

    Kelly, K J; Zhang, Jizhong; Han, Ling; Kamocka, Malgorzata; Miller, Caroline; Gattone, Vincent H; Dominguez, Jesus H

    2015-01-01

    Autosomal recessive polycystic kidney disease is a truly catastrophic monogenetic disease, causing death and end stage renal disease in neonates and children. Using PCK female rats, an orthologous model of autosomal recessive polycystic kidney disease harboring mutant Pkhd1, we tested the hypothesis that intravenous renal cell transplantation with normal Sprague Dawley male kidney cells would improve the polycystic kidney disease phenotype. Cytotherapy with renal cells expressing wild type Pkhd1 and tubulogenic serum amyloid A1 had powerful and sustained beneficial effects on renal function and structure in the polycystic kidney disease model. Donor cell engraftment and both mutant and wild type Pkhd1 were found in treated but not control PCK kidneys 15 weeks after the final cell infusion. To examine the mechanisms of global protection with a small number of transplanted cells, we tested the hypothesis that exosomes derived from normal Sprague Dawley cells can limit the cystic phenotype of PCK recipient cells. We found that renal exosomes originating from normal Sprague Dawley cells carried and transferred wild type Pkhd1 mRNA to PCK cells in vivo and in vitro and restricted cyst formation by cultured PCK cells. The results indicate that transplantation with renal cells containing wild type Pkhd1 improves renal structure and function in autosomal recessive polycystic kidney disease and may provide an intra-renal supply of normal Pkhd1 mRNA.

  3. Fanconi Bickel Syndrome: Novel Mutations in GLUT 2 Gene Causing a Distinguished Form of Renal Tubular Acidosis in Two Unrelated Egyptian Families

    Directory of Open Access Journals (Sweden)

    Mohammad Al-Haggar

    2011-01-01

    Full Text Available Background. Fanconi-Bickel syndrome (FBS is an autosomal recessive disorder caused by defects in facilitative glucose transporter 2 (GLUT2 or SLC2A2 gene mapped on chromosome 3q26.1-26.3, that codes for the glucose transporter protein 2. Methods. Two unrelated Egyptian families having suspected cases of FBS were enrolled after taking a written informed consent; both had positive consanguinity, and index cases had evidences of proximal renal tubular defects with hepatomegaly; they were subjected to history taking, signs of rickets as well as anthropometric measurements. Laboratory workup included urinalysis, renal and liver function tests including fasting and postprandial blood sugar; serum calcium, phosphorus, alkaline phosphatase, sodium and potassium, lipid profile, and detailed blood gas. Imaging including bone survey and abdominal ultrasound, and liver biopsy were done to confirm diagnosis. Molecular analysis of the GLUT2 gene was done for DNA samples extracted from peripheral blood leukocyte. All coding sequences, including flanking introns in GLUT2 gene, were amplified using PCR followed by direct sequencing. Results. Two new mutations had been detected, one in each family, in exon 3 two bases (GA were deleted (c.253 254delGA and in exon 6 in the second family, G-to-C substitution at position-1 of the splicing acceptor site (c.776-1G>C or IVS5-1G>A. Conclusion. FBS is a rare disease due to mutation in GLUT2 gene; many mutations were reported, about half were novel mutations; yet none of these mutations is more frequent. A more extensive survey for the most frequent mutations among FBS has to be contemplated to allow for use of molecular screening tests like ARMS.

  4. Effect of nitrendipine on renal function and on hormonal parameters after intravascular iopromide

    DEFF Research Database (Denmark)

    Madsen, J K; Jensen, J W; Sandermann, J

    1998-01-01

    PURPOSE: To evaluate the effect of the low-molecular nonionic radiographic contrast agent iopromide (Ultravist) on renal function, vasoactive peptides (angiotensin II, aldosterone, arginine vasopressin, and atrial natriuretic factor (ANF)), and blood pressure, and to evaluate the influence....... Renal tubular function was estimated from the clearance of lithium. Hormones were measured by radioimmunoassays. RESULTS: Arteriography with iopromide did not change renal function. No differences between the nitrendipine and placebo groups were found in renal hemodynamics, tubular sodium handling...

  5. Urinary alpha 1-microglobulin as an indicator protein of renal tubular dysfunction caused by environmental cadmium exposure

    Energy Technology Data Exchange (ETDEWEB)

    Tohyama, C.; Kobayashi, E.; Saito, H.; Sugihara, N.; Nakano, A.; Mitane, Y.

    1986-06-01

    An epidemiologic investigation was carried out to clarify the significance of the urinary excretion of alpha 1-microglobulin (alpha 1-MG) in people aged 50 years and over living in a Cd-polluted area in Japan. Approximately 80% of the population participated in the health examination. The urinary and serum levels and the relative clearance of alpha 1-MG to creatinine clearance were compared with various parameters (age, urinary beta 2-microglobulin (beta 2-MG), total protein, Cd, Cu and Zn, serum beta 2-MG, creatinine and blood urea nitrogen and relative clearances of alpha 1-MG, beta 2-MG, inorganic phosphate and uric acid). It was found that the urinary excretion of alpha 1-MG is closely associated with the urinary Cd and Cu and with the indices of renal dysfunction listed above. These results suggest that the urinary alpha 1-MG level markedly reflects a degree of proximal tubular dysfunction and that it may be useful as one of the screening measures for proximal tubular dysfunction caused by environmental Cd exposure.

  6. Efferent pathways in sodium overload-induced renal vasodilation in rats.

    Directory of Open Access Journals (Sweden)

    Nathalia O Amaral

    Full Text Available Hypernatremia stimulates the secretion of oxytocin (OT, but the physiological role of OT remains unclear. The present study sought to determine the involvement of OT and renal nerves in the renal responses to an intravenous infusion of hypertonic saline. Male Wistar rats (280-350 g were anesthetized with sodium thiopental (40 mg. kg(-1, i.v.. A bladder cannula was implanted for collection of urine. Animals were also instrumented for measurement of mean arterial pressure (MAP and renal blood flow (RBF. Renal vascular conductance (RVC was calculated as the ratio of RBF by MAP. In anesthetized rats (n = 6, OT infusion (0.03 µg • kg(-1, i.v. induced renal vasodilation. Consistent with this result, ex vivo experiments demonstrated that OT caused renal artery relaxation. Blockade of OT receptors (OXTR reduced these responses to OT, indicating a direct effect of this peptide on OXTR on this artery. Hypertonic saline (3 M NaCl, 1.8 ml • kg(-1 b.wt., i.v. was infused over 60 s. In sham rats (n = 6, hypertonic saline induced renal vasodilation. The OXTR antagonist (AT; atosiban, 40 µg • kg(-1 • h(-1, i.v.; n = 7 and renal denervation (RX reduced the renal vasodilation induced by hypernatremia. The combination of atosiban and renal denervation (RX+AT; n = 7 completely abolished the renal vasodilation induced by sodium overload. Intact rats excreted 51% of the injected sodium within 90 min. Natriuresis was slightly blunted by atosiban and renal denervation (42% and 39% of load, respectively, whereas atosiban with renal denervation reduced sodium excretion to 16% of the load. These results suggest that OT and renal nerves are involved in renal vasodilation and natriuresis induced by acute plasma hypernatremia.

  7. Regional anesthesia is safe and effective for lower limb orthopedic surgery in patient with renal tubular acidosis and hypokalemia

    Directory of Open Access Journals (Sweden)

    Indira Gurajala

    2018-01-01

    Full Text Available Renal tubular acidosis (RTA with hypokalemia may precipitate acute respiratory failure and potentially fatal arrhythmias like ventricular fibrillation. Though there are random reports of respiratory failure needing mechanical ventilation and sudden death in patients with RTA and hypokalemia, the anesthetic management of these patients has not been clearly elucidated. Acidosis and hypokalemia have significant interactions with both general and local anesthetics and alter their effect substantially. Proper preoperative planning and optimization are required for the safe conduct of anesthesia in this subset of patients. We describe a case of distal RTA, hypokalemia, and metabolic bone disease in whom central neuraxial anesthesia was effectively used for lower limb orthopedic surgery with no complications.

  8. Monoanionic 99mTc-tricarbonyl-aminopolycarboxylate complexes with uncharged pendant groups: Radiosynthesis and evaluation as potential renal tubular tracers

    International Nuclear Information System (INIS)

    Lipowska, Malgorzata; Klenc, Jeffrey; Jarkas, Nashwa; Marzilli, Luigi G.; Taylor, Andrew T.

    2017-01-01

    Introduction: 99m Tc(CO) 3 -nitrilotriacetic acid, 99m Tc(CO) 3 (NTA), is a new renal tubular agent with pharmacokinetic properties comparable to those of 131 I-OIH but the clearance of 99m Tc(CO) 3 (NTA) and 131 I-OIH is still less than the clearance of PAH, the gold standard for the measurement of effective renal plasma flow. At physiological pH, dianionic 99m Tc(CO) 3 (NTA) has a mononegative inner metal-coordination sphere and a mononegative uncoordinated carboxyl group. To evaluate alternate synthetic approaches, we assessed the importance of an uncoordinated carboxyl group, long considered essential for tubular transport, by evaluating the pharmacokinetics of three analogs with the 99m Tc(CO) 3 (NTA) metal-coordination sphere but with uncharged pendant groups. Methods: 99m Tc(CO) 3 complexes with N-(2-acetamido)iminodiacetic acid (ADA), N-(2-hydroxyethyl)iminodiacetic acid (HDA) and N-(fluoroethyl)iminodiacetic acid (FEDA) were prepared using a tricarbonyl kit and isolated by HPLC. The pharmacokinetics were evaluated in Sprague–Dawley rats, with 131 I-OIH as an internal control; urine was analyzed for metabolites. Plasma protein binding and erythrocyte uptake were determined from the 10 min blood samples. Re(CO) 3 (FEDA), the analog of 99m Tc(CO) 3 (FEDA), was prepared and characterized. Results: 99m Tc(CO) 3 (ADA), 99m Tc(CO) 3 (HDA) and 99m Tc(CO) 3 (FEDA) were efficiently prepared as a single species with high radiochemical purities (>99%). These new monoanionic 99m Tc(CO) 3 tracers with uncharged dangling groups all showed rapid blood clearance and high specificity for renal excretion. Activity in the urine, as a percent of 131 I-OIH at 10 and 60 min, was 96% and 99% for ADA, 96% and 100% for HDA, and 100% and 99% for FEDA, respectively. Each new tracer was excreted unchanged in the urine. The Re(CO) 3 (FEDA) structure adds compelling evidence that such 99m Tc(CO) 3 (NTA) analogs have metal-coordination spheres identical to that of 99m Tc(CO) 3 (NTA

  9. Renal vein oxygen saturation in renal artery stenosis

    DEFF Research Database (Denmark)

    Nielsen, K; Rehling, M; Henriksen, Jens Henrik Sahl

    1992-01-01

    Renal vein oxygen-saturation was measured in 56 patients with arterial hypertension and unilateral stenosis or occlusion of the renal artery. Oxygen-saturation in blood from the ischaemic kidney (84.4%, range 73-93%) was significantly higher than that from the 'normal' contralateral kidney (81...... than its blood flow. This is probably due to decreased filtration fraction and filtered sodium with subsequent reduction in absolute tubular re-absorption of sodium ions....

  10. Distal Renal Tubular Acidosis (dRTA) Among Southeast Asian Ovalocytosis (SAO) Patients in Malaria Endemic Area of Sekotong, Lombok Island

    OpenAIRE

    Danuyanti, I Gusti Ayu Nyoman; -, Tasmini; Sadewa, Ahmad Hamim

    2014-01-01

    Introduction: Southeast Asian Ovalocytosis (SAO) is caused by 27 bp deletion of the band 3 protein gene in erythrocyte membrane and characterized by oval erythrocyte. The erythroid band 3 (AE1) gene isexpressed not only in erythrocyte membranes but also in the cell membrane of α-collecting renal tubular functions in the secretion of acid in renal tubules and HCO3 -/Cl- anion exchange. An alteration of the band 3 (AE1) gene functions in cell of α-collecting renal tubules reduces HCO3-/Cl- ion ...

  11. Cisplatin toxicity reduced in human cultured renal tubular cells by oxygen pretreatment.

    Science.gov (United States)

    Kaeidi, Ayat; Rasoulian, Bahram; Hajializadeh, Zahra; Pourkhodadad, Soheila; Rezaei, Maryam

    2013-01-01

    Cisplatin is an effective and widely used chemotherapy agent and its side effects, particularly nephrotoxicity, limit its usage and related platinum-based drugs. Cisplatin nephrotoxicity is mainly due to extremely increase in reactive oxygen species (ROS) generation leading to kidney tubular cell death. Preconditioning with oxidative stress has been demonstrated to stimulate the cellular adaptation to subsequent severe oxidative stress. Short term oxygen pre-exposure as a mild oxidative stress may enhance some endogenous defense mechanisms, so its effect on Cisplatin induced cell death was investigated in present research. We studied the effects of hyperoxic environment pre-exposure on Cisplatin toxicity in an in-vitro model of cultured human embryonic tubular epithelial cells (AD293). Viability of AD293 cells, as evaluated by MTT-assay, was affected by Cisplatin in a time (1-4 h) dependent model. Biochemical markers of cell apoptosis were evaluated using immunoblotting. Pretreatment with nearly pure oxygen (≥90%) for 2 h significantly reduced the level of cell damage. Activated caspase 3 and Bax/Bcl-2 ratio were significantly increased in Cisplatin-treated cells. Oxygen pretreatment inhibited caspase 3 activation and decreased Bax/Bcl-2 ratio. Oxygen pre-treatment itself not showed any cytotoxicity in exposure times up to 3 h. Our data indicate that hyperoxic preconditioning reduces Cisplatin toxicity in cultured human tubular epithelial cells. The exact mechanism of protection is unclear, though enhancement of some endogenous defense mechanisms and subsequently scavenging of free oxygen radicals may play an important role.

  12. Endolymphatic Sac Enlargement in a Girl with a Novel Mutation for Distal Renal Tubular Acidosis and Severe Deafness

    Directory of Open Access Journals (Sweden)

    Rink Nikki

    2012-01-01

    Full Text Available Hereditary distal renal tubular acidosis (dRTA is caused by mutations of genes encoding subunits of the H+-ATPase (ATP6V0A4 and ATP6V1B1 expressed in α-intercalated cells of the distal renal tubule and in the cochlea. We report on a 2-year-old girl with distal RTA and profound speech delay which was initially misdiagnosed as autism. Genetic analysis showed compound heterozygous mutations with one known and one novel mutation of the ATP6V1B1 gene; cerebral magnetic resonance imaging (MRI revealed bilateral enlargement of the endolymphatic sacs of the inner ear. With improved cooperation, audiometric testing showed that hearing loss was most profound on the right, where endolymphatic sac enlargement was greatest, demonstrating a clear link between the degree of deafness and the degree of inner ear abnormality. This case indicates the value of MRI for diagnosis of inner ear involvement in very young children with distal RTA. Although citrate therapy quickly corrects the acidosis and restores growth, early diagnosis of deafness is crucial so that hearing aids can be used to assist acquisition of speech and to provide enough auditory nerve stimulation to assure the affected infants remain candidates for cochlear implantation.

  13. Downregulation of miR-205 modulates cell susceptibility to oxidative and endoplasmic reticulum stresses in renal tubular cells.

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    Shiyo Muratsu-Ikeda

    Full Text Available BACKGROUND: Oxidative stress and endoplasmic reticulum (ER stress play a crucial role in tubular damage in both acute kidney injury (AKI and chronic kidney disease (CKD. While the pathophysiological contribution of microRNAs (miRNA to renal damage has also been highlighted, the effect of miRNA on renal damage under oxidative and ER stresses conditions remains elusive. METHODS: We assessed changes in miRNA expression in the cultured renal tubular cell line HK-2 under hypoxia-reoxygenation-induced oxidative stress or ER stress using miRNA microarray assay and real-time RT-PCR. The pathophysiological effect of miRNA was evaluated by cell survival rate, intracellular reactive oxygen species (ROS level, and anti-oxidant enzyme expression in miRNA-inhibited HK-2 or miRNA-overexpressed HK-2 under these stress conditions. The target gene of miRNA was identified by 3'-UTR-luciferase assay. RESULTS: We identified 8 and 10 miRNAs whose expression was significantly altered by oxidative and ER stresses, respectively. Among these, expression of miR-205 was markedly decreased in both stress conditions. Functional analysis revealed that decreased miR-205 led to an increase in cell susceptibility to oxidative and ER stresses, and that this increase was associated with the induction of intracellular ROS and suppression of anti-oxidant enzymes. While increased miR-205 by itself made no change in cell growth or morphology, cell viability under oxidative or ER stress conditions was partially restored. Further, miR-205 bound to the 3'-UTR of the prolyl hydroxylase 1 (PHD1/EGLN2 gene and suppressed the transcription level of EGLN2, which modulates both intracellular ROS level and ER stress state. CONCLUSIONS: miR-205 serves a protective role against both oxidative and ER stresses via the suppression of EGLN2 and subsequent decrease in intracellular ROS. miR-205 may represent a novel therapeutic target in AKI and CKD associated with oxidative or ER stress in tubules.

  14. Limitation of HIF-1α with pentoxifillyne on renal tubular ischemia result of hiperoxaluria and ESWL.

    Science.gov (United States)

    Erturhan, Sakip; Bayrak, Omer; Seckiner, Ilker; Celik, Mehmet; Karakok, Metin

    2014-03-01

    To evaluate hypoxia-inducible factor 1 subunit α (HIF-1α) expression during the performance of extracorporeal shock wave lithotripsy (ESWL) and to investigate the effects of pentoxyphylline on HIF-1α expression. One hundred New Zealand Albino rabbit were used in the study divided in 5 groups. There were 20 rabbits in each group. The groups were divided in two parts: early (7 days) and late period (14 days) according to follow up duration. Immunohistochemical analyses were performed using nuclear staining to show HIF-1α expression in rabbit renal tissue sample. HIF-1α expression was higher in rabbits undergoing ESWL (group 4). In the hyperoxaluria group taking pentoxyphylline before ESWL (group 5), HIF-1α expression was lower in both early and late period subgroups (p ESWL may cause renal cell injury. Our results suggest that pentoxyphylline, as a circulatory regulator agent, may prevent renal cell injury induced by ESWL.

  15. Utilidad de la recolección de orina de dos horas para el diagnóstico del tipo de acidosis tubular renal

    Directory of Open Access Journals (Sweden)

    Margarita Irene Rocha-Gómez

    2015-08-01

    Full Text Available La acidosis tubular renal se caracteriza por acidosis metabólica hiperclorémica. El diagnóstico del tipo de acidosis tubular renal se realiza mediante la medición del transporte tubular máximo de bicarbonato y de la capacidad de acidificación urinaria; sin embargo, estas pruebas son invasivas y requieren determinaciones especializadas. Objetivo: comparar la utilidad de la recolección urinaria de dos horas, una prueba relativamente simple y al alcance de muchos laboratorios, con la medición del transporte tubular máximo de bicarbonato y con la capacidad de acidificación urinaria (procedimientos de referencia para clasificar el tipo de acidosis tubular renal en pacientes pediátricos. Material y método: el estudio se realizó en niños con diagnóstico de acidosis tubular renal. El primer día se recolectó la muestra sérica y urinaria de dos horas. Al día siguiente se efectuaron los procedimientos de referencia administrando bicarbonato de sodio en 8 horas; las muestras se colectaron cada hora y se determinaron la reabsorción de bicarbonato y la acidificación urinaria.  Resultados: se incluyeron 19 pacientes y en 17 casos la colección urinaria de dos horas confirmó el diagnóstico de los procedimientos de referencia. La recolección urinaria de dos horas tuvo sensibilidad de 0.94 y especificidad de 0.67 para el diagnóstico de acidosis tubular renal distal. Conclusión: la recolección de orina de dos horas se realiza en forma menos invasiva y ofrece resultados semejantes a los procedimientos de referencia.

  16. Renal blood flow, fractional excretion of sodium and acute kidney injury: time for a new paradigm?

    Science.gov (United States)

    Prowle, John; Bagshaw, Sean M; Bellomo, Rinaldo

    2012-12-01

    Global renal blood flow is considered pivotal to renal function. Decreased global renal blood flow (decreased perfusion) is further considered the major mechanism of reduced glomerular filtration rate responsible for the development of acute kidney injury (AKI) in critically ill patients. Additionally, urinary biochemical tests are widely taught to allow the differential diagnosis of prerenal (functional) AKI and intrinsic [structural AKI (so-called acute tubular necrosis)]. In this review we will examine recent evidence regarding these two key clinical paradigms. Recent animal experiments and clinical studies in humans using cine-phase contrast magnetic resonance technology are not consistent with the decreased perfusion paradigm. They suggest instead that changes in the intra-renal circulation including modification in efferent arteriolar function and intra-renal shunting are much more likely to be responsible for AKI, especially in sepsis. Similarly, recent human studies indicate the urinary biochemistry has limited diagnostic or prognostic ability and is dissociated form biomarker and microscopic evidence of tubular injury. Intra-renal microcirculatory changes are likely more important than changes in global blood flow in the development of AKI. Urinary biochemistry is not a clinically useful diagnostic or prognostic tool in critically ill patients at risk of or with AKI.

  17. Hereditary tubular transport disorders: implications for renal handling of Ca2+ and Mg2+.

    NARCIS (Netherlands)

    Dimke, H.; Hoenderop, J.G.J.; Bindels, R.J.M.

    2010-01-01

    The kidney plays an important role in maintaining the systemic Ca2+ and Mg2+ balance. Thus the renal reabsorptive capacity of these cations can be amended to adapt to disturbances in plasma Ca2+ and Mg2+ concentrations. The reabsorption of Ca2+ and Mg2+ is driven by transport of other electrolytes,

  18. Hyaluronan Biology and Regulation in Renal Tubular Epithelial Cells and its Role in Kidney Stone Disease

    NARCIS (Netherlands)

    M. Asselman (Marino)

    2008-01-01

    textabstractRenal stone disease is a widespread problem afflicting more and more people throughout the world. Epidemiological studies show an increase in incidence and prevalence rates. In North America and Europe the yearly incidence is estimated to be about 0.5% 1, 2. The prevalence of kidney

  19. Flozins, inhibitors of type 2 renal sodium-glucose co-transporter – not only antihyperglycemic drugs

    Directory of Open Access Journals (Sweden)

    Mizerski Grzegorz

    2015-09-01

    Full Text Available The kidneys play a crucial role in the regulation of the carbohydrate metabolism. In normal physiological conditions, the glucose that filters through the renal glomeruli is subsequently nearly totally reabsorbed in the proximal renal tubules. Two transporters are engaged in this process: sodium-glucose co-transporter type 1 (SGLT1, and sodium-glucose co-transporter type type 2 (SGLT2 - this being located in the luminal membrane of the renal tubular epithelial cells. It was found that the administration of dapagliflozin, a selective SGLT2 inhibitor, in patients with type 2 diabetes, is associated with the reduction of HbA1c concentration by 0.45-1.11%. Additional benefits from the treatment with dapagliflozin are the reduction of arterial blood pressure and a permanent reduction of body weight. This outcome is related to the effect of osmotic diuresis and to the considerable loss of the glucose load by way of urine excretion. Dapagliflozin may be successfully applied in type 2 diabetes monotherapy, as well as in combined therapy (including insulin, where it is equally effective as other oral anti-diabetic drugs. Of note: serious adverse effects of dapagliflozin administration are rarely observed. What is more, episodes of severe hypoglycaemia related with the treatment occur only sporadically, most often in the course of diabetes polytherapy. The most frequent effects of the SGLT2 inhibitors are inseparably associated with the mechanism of their action (the glucuretic effect, and cover urogenital infections with a mild clinical course. At present, clinical trials are being continued of the administration of several subsequent drugs from this group, the most advanced of these being the use of canagliflozin and empagliflozin.

  20. Decreases in renal functional reserve and proximal tubular fluid output in conscious oophorectomized rats

    DEFF Research Database (Denmark)

    Nielsen, Camilla Birch; Flyvbjerg, Allan; Bruun, Jens Meldgaard

    2003-01-01

    Age-dependent glomerulosclerosis with reduced GFR develops earlier among men than among women. Therefore, whether female sex hormones could prevent the age-dependent decrease in GFR was investigated. The kidney function in oophorectomized rats treated with placebo (OOX group), estrogen (OOX+E(2...... effects were prevented with administration of estrogen. Sham-operated rats demonstrated values for renal functional reserve and fractional lithium excretion that were between those observed for the OOX group and the groups treated with sex hormones....

  1. Sex steroids do not affect shigatoxin cytotoxicity on human renal tubular or glomerular cells

    Directory of Open Access Journals (Sweden)

    Kohan Donald E

    2002-08-01

    Full Text Available Abstract Background The greater susceptibility of children to renal injury in post-diarrheal hemolytic-uremic syndrome (HUS may be related, at least in part, to heightened renal cell sensitivity to the cytotoxic effect of Shiga toxin (Stx, the putative mediator of kidney damage in HUS. We hypothesized that sexual maturation, which coincides with a falling incidence of HUS, may induce a relatively Stx-resistant state in the renal cells. Methods Cultured human glomerular endothelial (HGEN, human glomerular visceral epithelial (HGEC and human proximal tubule (HPT cells were exposed to Stx-1 after pre-incubation with progesterone, β-estradiol or testosterone followed by determination of cytotoxicity. Results Under basal conditions, Stx-1 potently and dose-dependently killed HPT and HGEC, but had relatively little effect on HGEN. Pre-incubation for 1, 2 or 7 days with physiologic or pharmacologic concentrations of progesterone, β-estradiol or testosterone had no effect on Stx-1 cytotoxicity dose-response on any cell type. In addition, no steroid altered Gb3 expression (Stx receptor by any cell type at any time point. Conclusion These data do not support the notion that hormonal changes associated with puberty induce an Stx-resistant state within kidney cells.

  2. Renal blood flow, early distal sodium, and plasma renin concentrations during osmotic diuresis

    DEFF Research Database (Denmark)

    Leyssac, P P; Holstein-Rathlou, N H; Skøtt, O

    2000-01-01

    .6 mmHg. Urine flow increased 10-fold, and sodium excretion increased by 177%. Plasma renin concentration (PRC) increased by 58%. Renal blood flow and glomerular filtration rate decreased, however end-proximal flow remained unchanged. After a similar volume of hypotonic glucose (152 mM), ED......(NaCl) increased by 3.6 mM, (P renal hemodynamics, urine flow, sodium excretion rate, or PRC. Infusion of 300 micromol NaCl in a smaller volume caused ED(NaCl) to increase by 6.4 mM without significant changes in PRC. Urine flow and sodium excretion increased significantly...

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

    Science.gov (United States)

    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 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.

  4. Construction of bioartificial renal tubule assist device in vitro and its function of transporting sodium and glucose.

    Science.gov (United States)

    Dong, Xinggang; Chen, Jianghua; He, Qiang; Yang, Yi; Zhang, Wei

    2009-08-01

    To explore a new way of constructing bioartificial renal tubule assist device (RAD) in vitro and its function of transporting sodium (Na(+)) and glucose and to evaluate the application of atomic force microscope in the RAD construction, rat renal tubular epithelial cell line NRK-52E was cultured in vitro, seeded onto the outer surfaces of hollow fibers in a bioreactor, and then cultured for two weeks to construct RAD. Bioreactor hollow fibers without NRK-52E cells were used as control. The morphologies of attached cells were observed with scanning electron microscope, and the junctions of cells and polysulfone membrane were observed with atomic force microscope. Transportation of Na(+) and glucose was measured. Oubaine and phlorizin were used to inhibit the transporting property. The results showed that NRK-52E cells and polysulfone membrane were closely linked, as observed under atomic force microscope. After exposure to oubaine and phlorizin, transporting rates of Na(+) and glucose were decreased significantly in the RAD group as compared with that in the control group (Pconstructed successfully in vitro, and it is able to selectively transport Na(+) and glucose.

  5. Quantifying cellular mechanics and adhesion in renal tubular injury using single cell force spectroscopy.

    Science.gov (United States)

    Siamantouras, Eleftherios; Hills, Claire E; Squires, Paul E; Liu, Kuo-Kang

    2016-05-01

    Tubulointerstitial fibrosis represents the major underlying pathology of diabetic nephropathy where loss of cell-to-cell adhesion is a critical step. To date, research has predominantly focussed on the loss of cell surface molecular binding events that include altered protein ligation. In the current study, atomic force microscopy single cell force spectroscopy (AFM-SCFS) was used to quantify changes in cellular stiffness and cell adhesion in TGF-β1 treated kidney cells of the human proximal tubule (HK2). AFM indentation of TGF-β1 treated HK2 cells showed a significant increase (42%) in the elastic modulus (stiffness) compared to control. Fluorescence microscopy confirmed that increased cell stiffness is accompanied by reorganization of the cytoskeleton. The corresponding changes in stiffness, due to F-actin rearrangement, affected the work of detachment by changing the separation distance between two adherent cells. Overall, our novel data quantitatively demonstrate a correlation between cellular elasticity, adhesion and early morphologic/phenotypic changes associated with tubular injury. Diabetes affects many patients worldwide. One of the long term problems is diabetic nephropathy. Here, the authors utilized atomic force microscopy single cell force spectroscopy (AFM- SCFS) to study cellular stiffness and cell adhesion after TGF1 treatment in human proximal tubule kidney cells. The findings would help further understand the overall disease mechanism in diabetic patients. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Monoanionic 99mTc-tricarbonyl-aminopolycarboxylate complexes with uncharged pendant groups: Radiosynthesis and evaluation as potential renal tubular tracers.

    Science.gov (United States)

    Lipowska, Malgorzata; Klenc, Jeffrey; Jarkas, Nashwa; Marzilli, Luigi G; Taylor, Andrew T

    2017-04-01

    99m Tc(CO) 3 -nitrilotriacetic acid, 99m Tc(CO) 3 (NTA), is a new renal tubular agent with pharmacokinetic properties comparable to those of 131 I-OIH but the clearance of 99m Tc(CO) 3 (NTA) and 131 I-OIH is still less than the clearance of PAH, the gold standard for the measurement of effective renal plasma flow. At physiological pH, dianionic 99m Tc(CO) 3 (NTA) has a mononegative inner metal-coordination sphere and a mononegative uncoordinated carboxyl group. To evaluate alternate synthetic approaches, we assessed the importance of an uncoordinated carboxyl group, long considered essential for tubular transport, by evaluating the pharmacokinetics of three analogs with the 99m Tc(CO) 3 (NTA) metal-coordination sphere but with uncharged pendant groups. 99m Tc(CO) 3 complexes with N-(2-acetamido)iminodiacetic acid (ADA), N-(2-hydroxyethyl)iminodiacetic acid (HDA) and N-(fluoroethyl)iminodiacetic acid (FEDA) were prepared using a tricarbonyl kit and isolated by HPLC. The pharmacokinetics were evaluated in Sprague-Dawley rats, with 131 I-OIH as an internal control; urine was analyzed for metabolites. Plasma protein binding and erythrocyte uptake were determined from the 10min blood samples. Re(CO) 3 (FEDA), the analog of 99m Tc(CO) 3 (FEDA), was prepared and characterized. 99m Tc(CO) 3 (ADA), 99m Tc(CO) 3 (HDA) and 99m Tc(CO) 3 (FEDA) were efficiently prepared as a single species with high radiochemical purities (>99%). These new monoanionic 99m Tc(CO) 3 tracers with uncharged dangling groups all showed rapid blood clearance and high specificity for renal excretion. Activity in the urine, as a percent of 131 I-OIH at 10 and 60min, was 96% and 99% for ADA, 96% and 100% for HDA, and 100% and 99% for FEDA, respectively. Each new tracer was excreted unchanged in the urine. The Re(CO) 3 (FEDA) structure adds compelling evidence that such 99m Tc(CO) 3 (NTA) analogs have metal-coordination spheres identical to that of 99m Tc(CO) 3 (NTA). New tracers lacking the negatively

  7. Poly[ADP-ribose] polymerase-1 expression is related to cold ischemia, acute tubular necrosis, and delayed renal function in kidney transplantation.

    Directory of Open Access Journals (Sweden)

    Francisco O'Valle

    Full Text Available UNLABELLED: Cold ischemia time especially impacts on outcomes of expanded-criteria donor (ECD transplantation. Ischemia-reperfusion (IR injury produces excessive poly[ADP-Ribose] Polymerase-1 (PARP-1 activation. The present study explored the hypothesis that increased tubular expression of PARP-1 contributes to delayed renal function in suboptimal ECD kidney allografts and in non-ECD allografts that develop posttransplant acute tubular necrosis (ATN. MATERIALS AND METHODS: Nuclear PARP-1 immunohistochemical expression was studied in 326 paraffin-embedded renal allograft biopsies (193 with different degrees of ATN and 133 controls and in murine Parp-1 knockout model of IR injury. RESULTS: PARP-1 expression showed a significant relationship with cold ischemia time (r coefficient = 0.603, time to effective diuresis (r = 0.770, serum creatinine levels at biopsy (r = 0.649, and degree of ATN (r = 0.810 (p = 0.001, Pearson test. In the murine IR model, western blot showed an increase in PARP-1 that was blocked by Parp-1 inhibitor. Immunohistochemical study of PARP-1 in kidney allograft biopsies would allow early detection of possible delayed renal function, and the administration of PARP-1 inhibitors may offer a therapeutic option to reduce damage from IR in donor kidneys by preventing or minimizing ATN. In summary, these results suggest a pivotal role for PARP-1 in the ATN of renal transplantation. We propose the immunohistochemical assessment of PARP-1 in kidney allograft biopsies for early detection of a possible delayed renal function.

  8. Enhancing the Detection of Dysmorphic Red Blood Cells and Renal Tubular Epithelial Cells with a Modified Urinalysis Protocol.

    Science.gov (United States)

    Chu-Su, Yu; Shukuya, Kenichi; Yokoyama, Takashi; Lin, Wei-Chou; Chiang, Chih-Kang; Lin, Chii-Wann

    2017-01-11

    Urinary sediment is used to evaluate patients with possible urinary tract diseases. Currently, numerous protocols are applied to detect dysmorphic red blood cells (RBCs) and renal tubular epithelial cells (RTECs) in urinary sediment. However, distinct protocols are used by nephrologists and medical technologists for specimen concentration and observation, which leads to major discrepancies in the differential counts of formed elements such as dysmorphic RBCs and RTECs and might interfere with an accurate clinical diagnosis. To resolve these problems, we first tested a modified urinalysis protocol with an increased relative centrifuge force and concentration factor in 20 biopsy-confirmed glomerulonephritis patients with haematuria. We successfully improved the recovery ratio of dysmorphic RBCs in clinical specimens from 34.7% to 42.0% (P dysmorphic RBCs were detected using a bright field microscope, with results comparable to those using a standard phase contrast microscope. Finally, we applied Sternheimer stain to enhance the contrast of RTECs in the urinary sediments. We concluded that this modified urinalysis protocol significantly enhanced the quality of urinalysis.

  9. Renal sodium retention in cirrhotic rats depends on glucocorticoid-mediated activation of mineralocorticoid receptor due to decreased renal 11beta-HSD-2 activity

    DEFF Research Database (Denmark)

    Thiesson, Helle; Jensen, Boye L; Bistrup, Claus

    2007-01-01

    Downregulation of the renal glucocorticoid-metabolizing enzyme 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD-2) during liver cirrhosis may allow activation of the mineralocorticoid receptor (MR) by glucocorticoids and contribute to sodium retention. We tested this hypothesis in male Wistar...... rats with decompensated liver cirrhosis and ascites 7 wk after bile duct ligation (BDL). Renal 11beta-HSD-2 mRNA, protein, and activity were significantly decreased in decompensated rats. The urinary Na(+)/K(+) ratio was reduced by 40%. Renal epithelial sodium channel (ENaC) mRNA and immunostaining...... were only slightly affected. Complete metabolic studies, including fecal excretion, showed that the BDL rats had avid renal sodium retention. Treatment of the BDL rats with dexamethasone suppressed endogenous glucocorticoid production, normalized total sodium balance and renal sodium excretion...

  10. Berberine activates Nrf2 nuclear translocation and inhibits apoptosis induced by high glucose in renal tubular epithelial cells through a phosphatidylinositol 3-kinase/Akt-dependent mechanism.

    Science.gov (United States)

    Zhang, Xiuli; Liang, Dan; Lian, Xu; Jiang, Yan; He, Hui; Liang, Wei; Zhao, Yue; Chi, Zhi-Hong

    2016-06-01

    Apoptosis of tubular epithelial cells is a major feature of diabetic kidney disease, and hyperglycemia triggers the generation of free radicals and oxidant stress in tubular cells. Berberine (BBR) is identified as a potential anti-diabetic herbal medicine due to its beneficial effects on insulin sensitivity, glucose metabolism and glycolysis. In this study, the underlying mechanisms involved in the protective effects of BBR on high glucose-induced apoptosis were explored using cultured renal tubular epithelial cells (NRK-52E cells) and human kidney proximal tubular cell line (HK-2 cells). We identified the pivotal role of phosphatidylinositol 3-kinase (PI3K)/Akt in BBR cellular defense mechanisms and revealed the novel effect of BBR on nuclear factor (erythroid-derived 2)-related factor-2 (Nrf2) and heme oxygenase (HO)-1 in NRK-52E and HK-2 cells. BBR attenuated reactive oxygen species production, antioxidant defense (GSH and SOD) and oxidant-sensitive proteins (Nrf2 and HO-1), which also were blocked by LY294002 (an inhibitor of PI3K) in HG-treated NRK-52E and HK-2 cells. Furthermore, BBR improved mitochondrial function by increasing mitochondrial membrane potential. BBR-induced anti-apoptotic function was demonstrated by decreasing apoptotic proteins (cytochrome c, Bax, caspase3 and caspase9). All these findings suggest that BBR exerts the anti-apoptosis effects through activation of PI3K/Akt signal pathways and leads to activation of Nrf2 and induction of Nrf2 target genes, and consequently protecting the renal tubular epithelial cells from HG-induced apoptosis.

  11. Successful Management of Refractory Type 1 Renal Tubular Acidosis with Amiloride

    Directory of Open Access Journals (Sweden)

    Patrick Oguejiofor

    2017-01-01

    Full Text Available A 28-year-old female with history of hypothyroidism, Sjögren’s Syndrome, and Systemic Lupus Erythematosus (SLE presented with complaints of severe generalized weakness, muscle pain, nausea, vomiting, and anorexia. Physical examination was unremarkable. Laboratory test showed hypokalemia at 1.6 mmol/l, nonanion metabolic acidosis with HCO3 of 11 mmol/l, random urine pH of 7.0, and urine anion gap of 8 mmol/l. CT scan of the abdomen revealed bilateral nephrocalcinosis. A diagnosis of type 1 RTA likely secondary to Sjögren’s Syndrome was made. She was started on citric acid potassium citrate with escalating dosages to a maximum dose of 60 mEq daily and potassium chloride over 5 years without significant improvement in serum K+ and HCO3 levels. She had multiple emergency room visits for persistent muscle pain, generalized weakness, and cardiac arrhythmias. Citric acid potassium citrate was then replaced with sodium bicarbonate at 15.5 mEq every 6 hours which was continued for 2 years without significant improvement in her symptoms and electrolytes. Amiloride 5 mg daily was added to her regimen as a potassium sparing treatment with dramatic improvement in her symptoms and electrolyte levels (as shown in the figures. Amiloride was increased to 10 mg daily and potassium supplementation was discontinued without affecting her electrolytes. Her sodium bicarbonate was weaned to 7.7 mEq daily.

  12. No effect of dietary fish oil on renal hemodynamics, tubular function, and renal functional reserve in long-term renal transplant recipients

    DEFF Research Database (Denmark)

    Hansen, J M; Løkkegaard, H; Høy, Carl-Erik

    1995-01-01

    Dietary supplementation with fish oil rich in n-3 polyunsaturated fatty acids has been suggested to protect the kidney against cyclosporin A (CsA) toxicity. This study investigated the effects of a 10-wk dietary supplementation with fish oil on renal function and renal functional reserve in healt...... transplant recipients treated with a low maintenance dose of CsA had a well-preserved renal functional reserve, and dietary supplementation with fish oil in these patients did not improve renal function.......Dietary supplementation with fish oil rich in n-3 polyunsaturated fatty acids has been suggested to protect the kidney against cyclosporin A (CsA) toxicity. This study investigated the effects of a 10-wk dietary supplementation with fish oil on renal function and renal functional reserve in healthy...... volunteers (N = 9) and two groups of stable long-term kidney-transplanted patients treated with maintenance low-dose CsA (3.0 +/- 0.6 mg/kg; N = 9) or without CsA (N = 9). After an overnight fast, the subjects were water loaded, and clearance studies were performed, postponing morning medication. GFR...

  13. The Renal Sodium Bicarbonate Cotransporter NBCe2: Is It a Major Contributor to Sodium and pH Homeostasis?

    Science.gov (United States)

    Felder, Robin A; Jose, Pedro A; Xu, Peng; Gildea, John J

    2016-09-01

    The sodium bicarbonate cotransporter (NBCe2, aka NBC4) was originally isolated from the human testis and heart (Pushkin et al. IUBMB Life 50:13-19, 2000). Subsequently, NBCe2 was found in diverse locations where it plays a role in regulating sodium and bicarbonate transport, influencing intracellular, extracellular, interstitial, and ultimately plasma pH (Boron et al. J Exp Biol. 212:1697-1706, 2009; Parker and Boron, Physiol Rev. 93:803-959, 2013; Romero et al. Mol Asp Med. 34:159-182, 2013). NBCe2 is located in human and rodent renal-collecting duct and proximal tubule. While much is known about the two electrogenic sodium bicarbonate cotransporters, NBCe1 and NBCe2, in the regulation of sodium homeostasis and pH balance in the rodent kidney, little is known about their roles in human renal physiology. NBCe2 is located in the proximal tubule Golgi apparatus under basal conditions and then disperses throughout the cell, but particularly into the apical membrane microvilli, during various maneuvers that increase intracellular sodium. This review will summarize our current understanding of the distribution and function of NBCe2 in the human kidney and how genetic variants of its gene, SLC4A5, contribute to salt sensitivity of blood pressure.

  14. The cholinergic pathway alleviates acute oxygen and glucose deprivation induced renal tubular cell injury by reducing the secretion of inflammatory medium of macrophages

    Directory of Open Access Journals (Sweden)

    Ming WU

    2017-10-01

    Full Text Available Objective To investigate the effects of cholinergic pathway on acute renal tubular cell injury induced by acute oxygen and glucose deprivation. Methods Rat kidney macrophages were isolated and cultured for constructing macrophages and renal epithelial cells co-cultivating model of oxygen-glucose deprivation (OGD, and the model cells were divided into three groups: OGD alone group, acetylcholine (ACh 100μmol/L+OGD group and ACh + galantamine (Gal 10μmol/L+OGD group. The cells underwent OGD treatment for 1 hour, and normally cultured for 24 hours. The expressions of TNF alpha, IL-1 beta, and IL-10 in supernatant fluid were detected by ELISA, the renal tubular cell viability was determined by MTT assay, the expression of acetylcholine esterase (AChE mRNA and protein were determined by RT-qPCR and Western blotting. The activity of AChE was determined by colorimetric method. Results The expressions of TNF alpha (pg/ml in OGD, Ach+OGD group, Ach+Gal+OGD groups were 140.2±44.81, 119.46±4.42 and 103.31±1.62 respectively (P0.05; The values of renal tubular cell proliferation were 55.02%±6.28%, 66.65%±6.47%, and 79.75%±4.22% respectively (P0.05; those of AchE protein were 0.66±0.07, 0.74±0.04 and 0.67±0.06 respectively (P>0.05; The activity of AChE (kU/L was 0.51±0.02, 0.35±0.05 and 0.32±0.04 respectively (P=0.001, 0.001 and 0.368. Conclusions ACh and Gal could inhibit the secretion of inflammatory mediators and cholinesterase activity and can reduce the acute hypoxic renal tubular cell injury. The modulation of the cholinergic pathway in macrophages may be the important treatment method for acute renal injury in the future. DOI: 10.11855/j.issn.0577-7402.2017.08.01

  15. Renal function, sodium and water homeostasis in patients with ...

    African Journals Online (AJOL)

    At baseline there were no differences in inulin clearance, PAH clearance, fractional excretion of sodium and free water excretion. During and after the saline infusion both groups showed a significant increase in sodium excretion with a reduction in water excretion, while the PAH and inulin clearances remained unchanged.

  16. Gastrointestinal osmoreceptors and renal sodium excretion in humans

    DEFF Research Database (Denmark)

    Andersen, L.J.; Jensen, T.U.; Bestle, M.H.

    2000-01-01

    The hypothesis that natriuresis can be induced by stimulation of gastrointestinal osmoreceptors was tested in eight supine subjects on constant sodium intake (150 mmol NaCl/day). A sodium load equivalent to the amount contained in 10% of measured extracellular volume was administered by a nasogas......-angiotensin system....

  17. Necesidad de estudio genético para el diagnóstico de algunos casos de acidosis tubular renal distal

    Directory of Open Access Journals (Sweden)

    Manuel Heras Benito

    2016-09-01

    Full Text Available Describimos el caso de una mujer joven, que fue diagnosticada de insuficiencia renal avanzada, con un hallazgo casual de una nefrocalcinosis sin una etiología clara, al haberse encontrado asintomática a lo largo de su vida. El estudio genético por paneles de genes conocidos asociados a enfermedad tubulointersticial permitió descubrir una acidosis tubular renal distal autosómica dominante, asociada a una mutación de novo en el exón 14 del gen SLC4A1, que hubiera sido imposible diagnosticar clínicamente por lo avanzado de la enfermedad renal cuando fue descubierta.

  18. [Decursin reduces reactive oxygen species and inhibits cisplatin-induced apoptosis in rat renal tubular epithelial cells].

    Science.gov (United States)

    Li, Cuiqiong; Li, Jianchun; Fan, Junming; Meng, Lifeng; Cao, Ling

    2017-10-01

    Objective To study the mechanism underlying the inhibitory effect of decursin on the apoptosis of rat renal tubular epithelial cells NRK-52E induced by cisplatin. Methods First, CCK-8 assay was used to detect the effects of 0, 10, 20, 40, 80, 100, 150, 200 μmol/L decursin and 0, 5, 10, 20, 30, 40, 50 μg/mL cispatin treatment for 24 hours on cell proliferation in NRK-52E cells via determining the half inhibitory concentration (IC 50 ). Then, NRK-52E cells were stimulated with 20 μg/mL cisplatin combined with 10, 50, 100 μmol/L decursin, and cell activity was detected by CCK-8 assay. The cells were divided into normal control group, 20 μg/mL cisplatin stimulation group, and 10, 50, 100 μmol/L decursin treated groups. Cell morphological changes was observed under inverted microscope, morphological changes of nucleus was detected by DAPI staining, cell apoptosis was detected by flow cytometry, the level of intracellular ROS was detected by DCFH-DA staining, and the apoptosis marker proteins cleaved-caspase-3 and cleaved-PARP were examined by Western blot analysis. Results Compared with the normal control group, cisplatin significantly inhibited the activity of the cells, and IC 50 was about 20 μg/mL; compared with the model group, in the decursin pretreatment groups, the level of intracellular ROS decreased remarkably, the expressions of cleaved-casspase-3 and cleaved-PARP proteins were reduced, and cell apoptosis was depressed. Conclusion Decursin can decrease the intracellular ROS level and inhibit the apoptosis of NRK-52E cells induced by cisplatin.

  19. Macrophage-stimulating protein attenuates gentamicin-induced inflammation and apoptosis in human renal proximal tubular epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ko Eun [Department of Internal Medicine, Chonnam National University Medical School, Gwangju 501-757 (Korea, Republic of); Kim, Eun Young [Department of Physiology, Chonnam National University Medical School, Gwangju 501-757 (Korea, Republic of); Kim, Chang Seong; Choi, Joon Seok; Bae, Eun Hui; Ma, Seong Kwon [Department of Internal Medicine, Chonnam National University Medical School, Gwangju 501-757 (Korea, Republic of); Kim, Kyung Keun [Department of Pharmacology, Chonnam National University Medical School, Gwangju 501-757 (Korea, Republic of); Lee, Jong Un [Department of Physiology, Chonnam National University Medical School, Gwangju 501-757 (Korea, Republic of); Kim, Soo Wan, E-mail: skimw@chonnam.ac.kr [Department of Internal Medicine, Chonnam National University Medical School, Gwangju 501-757 (Korea, Republic of)

    2013-05-10

    Highlights: •MSP/RON system is activated in rat kidney damaged by gentamicin. •MSP inhibits GM-induced cellular apoptosis and inflammation in HK-2 cells. •MSP attenuates GM-induced activation of MAPKs and NF-κB pathways in HK-2 cells. -- Abstract: The present study aimed to investigate whether macrophage-stimulating protein (MSP) treatment attenuates renal apoptosis and inflammation in gentamicin (GM)-induced tubule injury and its underlying molecular mechanisms. To examine changes in MSP and its receptor, recepteur d’origine nantais (RON) in GM-induced nephropathy, rats were injected with GM for 7 days. Human renal proximal tubular epithelial (HK-2) cells were incubated with GM for 24 h in the presence of different concentrations of MSP and cell viability was measured by MTT assay. Apoptosis was determined by flow cytometry of cells stained with fluorescein isothiocyanate-conjugated annexin V protein and propidium iodide. Expression of Bcl-2, Bax, caspase-3, cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS), nuclear factor-kappa B (NF-κB), IκB-α, and mitogen-activated protein kinases (MAPKs) was analyzed by semiquantitative immunoblotting. MSP and RON expression was significantly greater in GM-treated rats, than in untreated controls. GM-treatment reduced HK-2 cell viability, an effect that was counteracted by MSP. Flow cytometry and DAPI staining revealed GM-induced apoptosis was prevented by MSP. GM reduced expression of anti-apoptotic protein Bcl-2 and induced expression of Bax and cleaved caspase 3; these effects and GM-induced expression of COX-2 and iNOS were also attenuated by MSP. GM caused MSP-reversible induction of phospho-ERK, phospho-JNK, and phospho-p38. GM induced NF-κB activation and degradation of IκB-α; the increase in nuclear NF-κB was blocked by inhibitors of ERK, JNK, p-38, or MSP pretreatment. These findings suggest that MSP attenuates GM-induced inflammation and apoptosis by inhibition of the MAPKs

  20. The renal handling of sodium and water is not affected by the standard-dose cisplatin treatment for testicular cancer

    DEFF Research Database (Denmark)

    Daugaard, G; Strandgaard, S; Holstein-Rathlou, N H

    1987-01-01

    Renal clearances of 51Cr-EDTA, lithium, sodium and potassium were measured before and after each of four consecutive treatment series with cisplatin in 15 men with testicular cancer. Since lithium is reabsorbed like sodium and water in the proximal tubules, but not reabsorbed to any measurable...... and all other parameters of glomerular filtration and renal sodium handling remained normal throughout the study (with the exception of a fall in fractional sodium excretion after the first treatment series). Plasma magnesium declined during all four treatment periods, signifying renal magnesium wasting....

  1. Servo-control of water and sodium homeostasis during renal clearance measurements in conscious rats

    DEFF Research Database (Denmark)

    Thomsen, Klaus; Shirley, David G

    2007-01-01

    Servo-controlled fluid and sodium replacement during clearance studies is used in order to prevent loss of body fluid and sodium following diuretic/natriuretic procedures. However, even under control conditions, the use of this technique is sometimes associated with increases in proximal tubular...... fluid output (assessed by lithium clearance) and excretion rates. The present study examined the reason for these increases. The first series of experiments showed that one cause is volume overloading. This can occur if the servo system is activated from the start, i.e., during the establishment...... not seen when blood samples are replaced with the animal's own red blood cells resuspended in isotonic saline. When these pitfalls are avoided, servo-controlled sodium and fluid replacement is a reliable technique that makes it possible to study the effects of natriuretic and/or diuretic stimuli without...

  2. Human Sodium Phosphate Transporter 4 (hNPT4/SLC17A3) as a Common Renal Secretory Pathway for Drugs and Urate*

    Science.gov (United States)

    Jutabha, Promsuk; Anzai, Naohiko; Kitamura, Kenichiro; Taniguchi, Atsuo; Kaneko, Shuji; Yan, Kunimasa; Yamada, Hideomi; Shimada, Hidetaka; Kimura, Toru; Katada, Tomohisa; Fukutomi, Toshiyuki; Tomita, Kimio; Urano, Wako; Yamanaka, Hisashi; Seki, George; Fujita, Toshiro; Moriyama, Yoshinori; Yamada, Akira; Uchida, Shunya; Wempe, Michael F.; Endou, Hitoshi; Sakurai, Hiroyuki

    2010-01-01

    The evolutionary loss of hepatic urate oxidase (uricase) has resulted in humans with elevated serum uric acid (urate). Uricase loss may have been beneficial to early primate survival. However, an elevated serum urate has predisposed man to hyperuricemia, a metabolic disturbance leading to gout, hypertension, and various cardiovascular diseases. Human serum urate levels are largely determined by urate reabsorption and secretion in the kidney. Renal urate reabsorption is controlled via two proximal tubular urate transporters: apical URAT1 (SLC22A12) and basolateral URATv1/GLUT9 (SLC2A9). In contrast, the molecular mechanism(s) for renal urate secretion remain unknown. In this report, we demonstrate that an orphan transporter hNPT4 (human sodium phosphate transporter 4; SLC17A3) was a multispecific organic anion efflux transporter expressed in the kidneys and liver. hNPT4 was localized at the apical side of renal tubules and functioned as a voltage-driven urate transporter. Furthermore, loop diuretics, such as furosemide and bumetanide, substantially interacted with hNPT4. Thus, this protein is likely to act as a common secretion route for both drugs and may play an important role in diuretics-induced hyperuricemia. The in vivo role of hNPT4 was suggested by two hyperuricemia patients with missense mutations in SLC17A3. These mutated versions of hNPT4 exhibited reduced urate efflux when they were expressed in Xenopus oocytes. Our findings will complete a model of urate secretion in the renal tubular cell, where intracellular urate taken up via OAT1 and/or OAT3 from the blood exits from the cell into the lumen via hNPT4. PMID:20810651

  3. Dietary sodium modulation of aldosterone activation and renal function during the progression of experimental heart failure.

    Science.gov (United States)

    Miller, Wayne L; Borgeson, Daniel D; Grantham, J Aaron; Luchner, Andreas; Redfield, Margaret M; Burnett, John C

    2015-02-01

    Aldosterone activation is central to the sodium–fluid retention that marks the progression of heart failure (HF). The actions of dietary sodium restriction, a mainstay in HF management, on cardiorenal and neuroendocrine adaptations during the progression of HF are poorly understood. The study aim was to assess the role of dietary sodium during the progression of experimental HF. Experimental HF was produced in a canine model by rapid right ventricular pacing which evolves from early mild HF to overt, severe HF. Dogs were fed one of three diets: (i) high sodium [250 mEq (5.8 g) per day, n =6]; (ii) standard sodium [58 mEq (1.3 g) per day, n =6]; and (iii) sodium restriction [11 mEq (0.25 g) per day, n =6]. During the 38-day study, haemodynamics, renal function, plasma renin activity (PRA), and aldosterone were measured. Changes in haemodynamics at 38 days were similar in all three groups, as were changes in renal function. Aldosterone activation was demonstrated in all three groups; however, dietary sodium restriction, in contrast to high sodium, resulted in early (10 days) activation of PRA and aldosterone. High sodium demonstrated significant suppression of aldosterone activation over the course of HF progression. Excessive dietary sodium restriction particularly in early stage HF results in early aldosterone activation, while normal and excess sodium intake are associated with delayed or suppressed activation. These findings warrant evaluation in humans to determine if dietary sodium manipulation, particularly during early stage HF, may have a significant impact on neuroendocrine disease progression.

  4. Urinary NGAL Ratio Is Not a Sensitive Biomarker for Monitoring Acute Tubular Injury in Kidney Transplant Patients: NGAL and ATI in Renal Transplant Patients

    Directory of Open Access Journals (Sweden)

    Jessica K. Kaufeld

    2012-01-01

    Full Text Available Urinary neutrophil gelatinase-associated lipocalin (uNGAL is known to predict the prolonged delayed graft function after kidney transplantation. We examined the relation of uNGAL with histological findings of acute tubular injury (ATI. Analyses were made in biopsies taken at 6 weeks, 3 months, and 6 months after kidney transplantation. uNGAL was measured in the spot urines, normalized to urinary creatinine excretion, and correlated to biopsy findings and clinical, laboratory, and demographic variables. Controls included healthy individuals, individuals after kidney donation and ICU patients with acute kidney failure. Renal transplant recipients without ATI did not display elevated uNGAL levels compared to the healthy controls. Transplant patients with ATI had a higher uNGAL excretion at 6 weeks than patients without ATI (27,435 versus 13,605 ng/g; P=0.031. This increase in uNGAL was minor compared to ICU patients with acute renal failure (2.05×106 ng/g. Patients with repeated findings of ATI or severe ATI did not have higher urinary NGAL levels compared to those with only one ATI finding or moderate ATI. Female recipient gender and urinary tract infection were identified as potential confounders. uNGAL has a relation with histological signs of acute tubular injury. The usability of this biomarker in renal allograft recipients is limited because of the low sensitivity.

  5. C-peptide increases Na,K-ATPase expression via PKC- and MAP kinase-dependent activation of transcription factor ZEB in human renal tubular cells.

    Directory of Open Access Journals (Sweden)

    Dana Galuska

    Full Text Available Replacement of proinsulin C-peptide in type 1 diabetes ameliorates nerve and kidney dysfunction, conditions which are associated with a decrease in Na,K-ATPase activity. We determined the molecular mechanism by which long term exposure to C-peptide stimulates Na,K-ATPase expression and activity in primary human renal tubular cells (HRTC in control and hyperglycemic conditions.HRTC were cultured from the outer cortex obtained from patients undergoing elective nephrectomy. Ouabain-sensitive rubidium ((86Rb(+ uptake and Na,K-ATPase activity were determined. Abundance of Na,K-ATPase was determined by Western blotting in intact cells or isolated basolateral membranes (BLM. DNA binding activity was determined by electrical mobility shift assay (EMSA. Culturing of HRTCs for 5 days with 1 nM, but not 10 nM of human C-peptide leads to increase in Na,K-ATPase α(1-subunit protein expression, accompanied with increase in (86Rb(+ uptake, both in normal- and hyperglycemic conditions. Na,K-ATPase α(1-subunit expression and Na,K-ATPase activity were reduced in BLM isolated from cells cultured in presence of high glucose. Exposure to1 nM, but not 10 nM of C-peptide increased PKCε phosphorylation as well as phosphorylation and abundance of nuclear ERK1/2 regardless of glucose concentration. Exposure to 1 nM of C-peptide increased DNA binding activity of transcription factor ZEB (AREB6, concomitant with Na,K-ATPase α(1-subunit mRNA expression. Effects of 1 nM C-peptide on Na,K-ATPase α(1-subunit expression and/or ZEB DNA binding activity in HRTC were abolished by incubation with PKC or MEK1/2 inhibitors and ZEB siRNA silencing.Despite activation of ERK1/2 and PKC by hyperglycemia, a distinct pool of PKCs and ERK1/2 is involved in regulation of Na,K-ATPase expression and activity by C-peptide. Most likely C-peptide stimulates sodium pump expression via activation of ZEB, a transcription factor that has not been previously implicated in C

  6. Moderation of dietary sodium potentiates the renal and cardiovascular protective effects of angiotensin receptor blockers

    DEFF Research Database (Denmark)

    Lambers Heerspink, Hiddo J; Holtkamp, Frank A; Parving, Hans-Henrik

    2012-01-01

    Dietary sodium restriction has been shown to enhance the short-term response of blood pressure and albuminuria to angiotensin receptor blockers (ARBs). Whether this also enhances the long-term renal and cardiovascular protective effects of ARBs is unknown. Here we conducted a post-hoc analysis of...

  7. Fetal development and renal function in adult rats prenatally subjected to sodium overload.

    Science.gov (United States)

    Cardoso, Henriqueta D; Cabral, Edjair V; Vieira-Filho, Leucio D; Vieyra, Adalberto; Paixão, Ana D O

    2009-10-01

    The aims of this study were (1) to evaluate two factors that affect fetal development--placental oxidative stress (Ox) and plasma volume (PV)--in dams with sodium overload and (2) to correlate possible alterations in these factors with subsequent modifications in the renal function of adult offspring. Wistar dams were maintained on 0.17 M NaCl instead of water from 20 days before mating until either the twentieth pregnancy day/parturition or weaning. Colorimetric methods were used to measure Ox in maternal and offspring tissues, PV, 24-h urinary protein (U(Prot24 h)) and serum triacylglycerols (TG) and cholesterol (Chol). Renal hemodynamics was evaluated in the offspring at 90 days of age using a blood pressure transducer, a flow probe and inulin clearance to measure mean arterial pressure (MAP), renal blood flow and glomerular filtration rate (GFR), respectively. The number of nephrons (NN) was counted in kidney suspensions. Dams showed unchanged PV, placental Ox and fetal weight but increased U(Prot24 h) (150%, P sodium-overloaded pups showed increased U(Prot24 h) (45%, P sodium-overloaded rats showed increased U(Prot24 h) (27%, P sodium-overloaded group. We conclude that salt overload from the prenatal stage until weaning leads to alterations in lipid metabolism and in the renal function of the pups, which are additional to those alterations seen in rats only overloaded prenatally.

  8. Role of IGFBP7 in Diabetic Nephropathy: TGF-β1 Induces IGFBP7 via Smad2/4 in Human Renal Proximal Tubular Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Jun Watanabe

    Full Text Available Tubular injury is one of the important determinants of progressive renal failure in diabetic nephropathy (DN, and TGF-β1 has been implicated in the pathogenesis of tubulointerstitial disease that characterizes proteinuric renal disease. The aim of this study was to identify novel therapeutic target molecules that play a role in the tubule damage of DN. We used an LC-MS/MS-based proteomic technique and human renal proximal epithelial cells (HRPTECs. Urine samples from Japanese patients with type 2 diabetes (n = 46 were used to quantify the candidate protein. Several proteins in HRPTECs in cultured media were observed to be driven by TGF-β1, one of which was 33-kDa IGFBP7, which is a member of IGFBP family. TGF-β1 up-regulated the expressions of IGFBP7 mRNA and protein in a dose- and time-dependent fashion via Smad2 and 4, but not MAPK pathways in HRPTECs. In addition, the knockdown of IGFBP7 restored the TGF-β1-induced epithelial to mesenchymal transition (EMT. In the immunohistochemical analysis, IGFBP7 was localized to the cytoplasm of tubular cells but not that of glomerular cells in diabetic kidney. Urinary IGFBP7 levels were significantly higher in the patients with macroalbuminuria and were correlated with age (r = 0.308, p = 0.037, eGFR (r = -0.376, p = 0.01, urinary β2-microglobulin (r = 0.385, p = 0.008, and urinary N-acetyl-beta-D-glucosaminidase (NAG (r = 0.502, p = 0.000. A multivariate regression analysis identified urinary NAG and age as determinants associated with urinary IGFBP7 levels. In conclusion, our data suggest that TGF-β1 enhances IGFBP7 via Smad2/4 pathways, and that IGFBP7 might be involved in the TGF-β1-induced tubular injury in DN.

  9. Sodium intake, RAAS-blockade and progressive renal disease

    NARCIS (Netherlands)

    de Borst, Martin H; Navis, Gerjan

    Pharmacological blockade of the renin-angiotensin-aldosterone system (RAAS) by angiotensin converting enzyme inhibitors or angiotensin receptor blockers is the current standard treatment to prevent progressive renal function loss in patients with chronic kidney disease. Yet in many patients the

  10. Indomethacin reduces glomerular and tubular damage markers but not renal inflammation in chronic kidney disease patients: a post-hoc analysis.

    Directory of Open Access Journals (Sweden)

    Martin H de Borst

    Full Text Available Under specific conditions non-steroidal anti-inflammatory drugs (NSAIDs may be used to lower therapy-resistant proteinuria. The potentially beneficial anti-proteinuric, tubulo-protective, and anti-inflammatory effects of NSAIDs may be offset by an increased risk of (renal side effects. We investigated the effect of indomethacin on urinary markers of glomerular and tubular damage and renal inflammation. We performed a post-hoc analysis of a prospective open-label crossover study in chronic kidney disease patients (n = 12 with mild renal function impairment and stable residual proteinuria of 4.7±4.1 g/d. After a wash-out period of six wks without any RAAS blocking agents or other therapy to lower proteinuria (untreated proteinuria (UP, patients subsequently received indomethacin 75 mg BID for 4 wks (NSAID. Healthy subjects (n = 10 screened for kidney donation served as controls. Urine and plasma levels of total IgG, IgG4, KIM-1, beta-2-microglobulin, H-FABP, MCP-1 and NGAL were determined using ELISA. Following NSAID treatment, 24 h -urinary excretion of glomerular and proximal tubular damage markers was reduced in comparison with the period without anti-proteinuric treatment (total IgG: UP 131[38-513] vs NSAID 38[17-218] mg/24 h, p<0.01; IgG4: 50[16-68] vs 10[1-38] mg/24 h, p<0.001; beta-2-microglobulin: 200[55-404] vs 50[28-110] ug/24 h, p = 0.03; KIM-1: 9[5]-[14] vs 5[2]-[9] ug/24 h, p = 0.01. Fractional excretions of these damage markers were also reduced by NSAID. The distal tubular marker H-FABP showed a trend to reduction following NSAID treatment. Surprisingly, NSAID treatment did not reduce urinary excretion of the inflammation markers MCP-1 and NGAL, but did reduce plasma MCP-1 levels, resulting in an increased fractional MCP-1 excretion. In conclusion, the anti-proteinuric effect of indomethacin is associated with reduced urinary excretion of glomerular and tubular damage markers, but not with reduced excretion of renal

  11. Mineralocorticoid-induced sodium appetite and renal salt retention: Evidence for common signaling and effector mechanisms

    Science.gov (United States)

    Fu, Yiling; Vallon, Volker

    2014-01-01

    An increase in renal sodium chloride (salt) retention and an increase in sodium appetite is the body's response to salt restriction or depletion in order to restore salt balance. Renal salt retention and increased sodium appetite can also be maladaptive and sustain the pathophysiology in conditions like salt-sensitive hypertension and chronic heart failure. Here we review the central role of the mineralocorticoid aldosterone in both the increase in renal salt reabsorption and sodium appetite. We discuss the working hypothesis that aldosterone activates similar signaling and effector mechanisms in the kidney and brain, including the mineralocorticoid receptor, the serum-and-glucocorticoid-induced kinase SGK1, the ubiquitin ligase NEDD4-2, and the epithelial sodium channel ENaC. The latter also mediates the gustatory salt sensing in the tongue, which is required for the manifestation of increased salt intake. Effects of aldosterone on both brain and kidney synergize with the effects of angiotensin II. Thus, mineralocorticoids appear to induce similar molecular pathways in the kidney, brain, and possibly tongue, which could provide opportunities for more effective therapeutic interventions. Inhibition of renal salt reabsorption is compensated by stimulation of salt appetite and vice versa; targeting both mechanisms should be more effective. Inhibiting the arousal to consume salty food may improve a patient's compliance to reducing salt intake. While a better understanding of the molecular mechanisms is needed and will provide new options, current pharmacological interventions that target both salt retention and sodium appetite include mineralocorticoid receptor antagonists and potentially inhibitors of angiotensin II and ENaC. PMID:25376899

  12. Genome-wide analysis of murine renal distal convoluted tubular cells for the target genes of mineralocorticoid receptor

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Kohei [Department of Nephrology and Endocrinology, The University of Tokyo, Tokyo (Japan); Fujiki, Katsunori; Shirahige, Katsuhiko [Research Center for Epigenetic Disease, Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo (Japan); Gomez-Sanchez, Celso E. [Endocrine Section, G.V. (Sonny) Montgomery VA Medical Center, MS (United States); Endocrinology, University of Mississippi Medical Center, MS (United States); Fujita, Toshiro [Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo (Japan); Nangaku, Masaomi [Department of Nephrology and Endocrinology, The University of Tokyo, Tokyo (Japan); Nagase, Miki, E-mail: mnagase-tky@umin.ac.jp [Department of Nephrology and Endocrinology, The University of Tokyo, Tokyo (Japan); Department of Anatomy and Life Structure, School of Medicine Juntendo University, Tokyo (Japan)

    2014-02-28

    Highlights: • We define a target gene of MR as that with MR-binding to the adjacent region of DNA. • We use ChIP-seq analysis in combination with microarray. • We, for the first time, explore the genome-wide binding profile of MR. • We reveal 5 genes as the direct target genes of MR in the renal epithelial cell-line. - Abstract: Background and objective: Mineralocorticoid receptor (MR) is a member of nuclear receptor family proteins and contributes to fluid homeostasis in the kidney. Although aldosterone-MR pathway induces several gene expressions in the kidney, it is often unclear whether the gene expressions are accompanied by direct regulations of MR through its binding to the regulatory region of each gene. The purpose of this study is to identify the direct target genes of MR in a murine distal convoluted tubular epithelial cell-line (mDCT). Methods: We analyzed the DNA samples of mDCT cells overexpressing 3xFLAG-hMR after treatment with 10{sup −7} M aldosterone for 1 h by chromatin immunoprecipitation with deep-sequence (ChIP-seq) and mRNA of the cell-line with treatment of 10{sup −7} M aldosterone for 3 h by microarray. Results: 3xFLAG-hMR overexpressed in mDCT cells accumulated in the nucleus in response to 10{sup −9} M aldosterone. Twenty-five genes were indicated as the candidate target genes of MR by ChIP-seq and microarray analyses. Five genes, Sgk1, Fkbp5, Rasl12, Tns1 and Tsc22d3 (Gilz), were validated as the direct target genes of MR by quantitative RT-qPCR and ChIP-qPCR. MR binding regions adjacent to Ctgf and Serpine1 were also validated. Conclusions: We, for the first time, captured the genome-wide distribution of MR in mDCT cells and, furthermore, identified five MR target genes in the cell-line. These results will contribute to further studies on the mechanisms of kidney diseases.

  13. Thiazolidinediones and Edema: Recent Advances in the Pathogenesis of Thiazolidinediones-Induced Renal Sodium Retention

    Directory of Open Access Journals (Sweden)

    Shoko Horita

    2015-01-01

    Full Text Available Thiazolidinediones (TZDs are one of the major classes of antidiabetic drugs that are used widely. TZDs improve insulin resistance by activating peroxisome proliferator-activated receptor gamma (PPARγ and ameliorate diabetic and other nephropathies, at least, in experimental animals. However, TZDs have side effects, such as edema, congestive heart failure, and bone fracture, and may increase bladder cancer risk. Edema and heart failure, which both probably originate from renal sodium retention, are of great importance because these side effects make it difficult to continue the use of TZDs. However, the pathogenesis of edema remains a matter of controversy. Initially, upregulation of the epithelial sodium channel (ENaC in the collecting ducts by TZDs was thought to be the primary cause of edema. However, the results of other studies do not support this view. Recent data suggest the involvement of transporters in the proximal tubule, such as sodium-bicarbonate cotransporter and sodium-proton exchanger. Other studies have suggested that sodium-potassium-chloride cotransporter 2 in the thick ascending limb of Henle and aquaporins are also possible targets for TZDs. This paper will discuss the recent advances in the pathogenesis of TZD-induced sodium reabsorption in the renal tubules and edema.

  14. Thiazolidinediones and Edema: Recent Advances in the Pathogenesis of Thiazolidinediones-Induced Renal Sodium Retention.

    Science.gov (United States)

    Horita, Shoko; Nakamura, Motonobu; Satoh, Nobuhiko; Suzuki, Masashi; Seki, George

    2015-01-01

    Thiazolidinediones (TZDs) are one of the major classes of antidiabetic drugs that are used widely. TZDs improve insulin resistance by activating peroxisome proliferator-activated receptor gamma (PPARγ) and ameliorate diabetic and other nephropathies, at least, in experimental animals. However, TZDs have side effects, such as edema, congestive heart failure, and bone fracture, and may increase bladder cancer risk. Edema and heart failure, which both probably originate from renal sodium retention, are of great importance because these side effects make it difficult to continue the use of TZDs. However, the pathogenesis of edema remains a matter of controversy. Initially, upregulation of the epithelial sodium channel (ENaC) in the collecting ducts by TZDs was thought to be the primary cause of edema. However, the results of other studies do not support this view. Recent data suggest the involvement of transporters in the proximal tubule, such as sodium-bicarbonate cotransporter and sodium-proton exchanger. Other studies have suggested that sodium-potassium-chloride cotransporter 2 in the thick ascending limb of Henle and aquaporins are also possible targets for TZDs. This paper will discuss the recent advances in the pathogenesis of TZD-induced sodium reabsorption in the renal tubules and edema.

  15. Renal Tubular Acidosis

    Science.gov (United States)

    ... is called transport. One researcher has theorized that Charles Dickens may have been describing a child with ... urine and the potassium level in the blood will help identify which type of RTA a person ...

  16. Renal Tubular Acidosis

    Science.gov (United States)

    ... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... More on this topic for: Parents Kids Teens Definition: Kidney Living With Lupus Nephrotic Syndrome Vesicoureteral Reflux ( ...

  17. Proximal renal tubular acidosis

    Science.gov (United States)

    ... or decreased alertness Dehydration Fatigue Increased breathing rate Osteomalacia (softening of the bones) Muscle pain Weakness Other ... correct bone disorders and reduce the risk of osteomalacia and osteopenia in adults. Some adults may need ...

  18. Characterization of Organic Anion Transporter 2 (SLC22A7): A Highly Efficient Transporter for Creatinine and Species-Dependent Renal Tubular Expression.

    Science.gov (United States)

    Shen, Hong; Liu, Tongtong; Morse, Bridget L; Zhao, Yue; Zhang, Yueping; Qiu, Xi; Chen, Cliff; Lewin, Anne C; Wang, Xi-Tao; Liu, Guowen; Christopher, Lisa J; Marathe, Punit; Lai, Yurong

    2015-07-01

    The contribution of organic anion transporter OAT2 (SLC22A7) to the renal tubular secretion of creatinine and its exact localization in the kidney are reportedly controversial. In the present investigation, the transport of creatinine was assessed in human embryonic kidney (HEK) cells that stably expressed human OAT2 (OAT2-HEK) and isolated human renal proximal tubule cells (HRPTCs). The tubular localization of OAT2 in human, monkey, and rat kidney was characterized. The overexpression of OAT2 significantly enhanced the uptake of creatinine in OAT2-HEK cells. Under physiologic conditions (creatinine concentrations of 41.2 and 123.5 µM), the initial rate of OAT2-mediated creatinine transport was approximately 11-, 80-, and 80-fold higher than OCT2, multidrug and toxin extrusion protein (MATE)1, and MATE2K, respectively, resulting in approximately 37-, 1850-, and 80-fold increase of the intrinsic transport clearance when normalized to the transporter protein concentrations. Creatinine intracellular uptake and transcellular transport in HRPTCs were decreased in the presence of 50 µM bromosulfophthalein and 100 µM indomethacin, which inhibited OAT2 more potently than other known creatinine transporters, OCT2 and multidrug and toxin extrusion proteins MATE1 and MATE2K (IC50: 1.3 µM vs. > 100 µM and 2.1 µM vs. > 200 µM for bromosulfophthalein and indomethacin, respectively) Immunohistochemistry analysis showed that OAT2 protein was localized to both basolateral and apical membranes of human and cynomolgus monkey renal proximal tubules, but appeared only on the apical membrane of rat proximal tubules. Collectively, the findings revealed the important role of OAT2 in renal secretion and possible reabsorption of creatinine and suggested a molecular basis for potential species difference in the transporter handling of creatinine. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

  19. Significance of downregulation of renal organic cation transporter (SLC47A1 in cisplatin-induced proximal tubular injury

    Directory of Open Access Journals (Sweden)

    Mizuno T

    2015-07-01

    Full Text Available Tomohiro Mizuno,1–3 Waichi Sato,2,3 Kazuhiro Ishikawa,4 Yuki Terao,1 Kazuo Takahashi,2 Yukihiro Noda,5 Yukio Yuzawa,2 Tadashi Nagamatsu1 1Department of Analytical Pharmacology, Meijo University Faculty of Pharmacy, Nagoya, 2Department of Nephrology, School of Medicine, Fujita Health University, Toyoake, 3Department of Nephrology, Nagoya University School of Medicine, Nagoya, 4Department of Neuropsychopharmacology and Hospital Pharmacy, Nagoya University Graduate School of Medicine, Nagoya, 5Division of Clinical Sciences and Neuropsychopharmacology, Meijo University Faculty of Pharmacy, Nagoya, Japan Background/aim: To elucidate the mechanism responsible for developing acute kidney injury in patients with diabetes mellitus, we also evaluated the issue of whether advanced glycation endproducts (AGEs influence the expressions of multi antimicrobial extrusion protein (MATE1/SLC47A1 in tubular cells. Materials and methods: To detect changing expression of MATE1/SLC47A1 in dose- and time-dependent manners, human proximal tubular epithelial cells were incubated with AGE-aggregated-human serum albumin. As a function assay for MATE1/SLC47A1, human proximal tubular epithelial cells were incubated with cisplatin or carboplatin. Results: On incubation with AGEs, the expressions of MATE1/SLC47A1 were decreased in tubular cells. In addition, the toxicities of cisplatin were increased in tubular cells that had been pretreated with AGEs. However, the toxicities of carboplatin were smaller than that of cisplatin in proximal tubular epithelial cells. Conclusion: The expression of the MATE1/SLC47A1 is decreased by AGEs, which increases the risk for proximal tubular injury. Keywords: advanced glycation endproducts, cisplatin, SLC47A1, diabetes mellitus, acute kidney injury

  20. Identification of genomic biomarkers for concurrent diagnosis of drug-induced renal tubular injury using a large-scale toxicogenomics database

    International Nuclear Information System (INIS)

    Kondo, Chiaki; Minowa, Yohsuke; Uehara, Takeki; Okuno, Yasushi; Nakatsu, Noriyuki; Ono, Atsushi; Maruyama, Toshiyuki; Kato, Ikuo; Yamate, Jyoji; Yamada, Hiroshi; Ohno, Yasuo; Urushidani, Tetsuro

    2009-01-01

    Drug-induced renal tubular injury is one of the major concerns in preclinical safety evaluations. Toxicogenomics is becoming a generally accepted approach for identifying chemicals with potential safety problems. In the present study, we analyzed 33 nephrotoxicants and 8 non-nephrotoxic hepatotoxicants to elucidate time- and dose-dependent global gene expression changes associated with proximal tubular toxicity. The compounds were administered orally or intravenously once daily to male Sprague-Dawley rats. The animals were exposed to four different doses of the compounds, and kidney tissues were collected on days 4, 8, 15, and 29. Gene expression profiles were generated from kidney RNA by using Affymetrix GeneChips and analyzed in conjunction with the histopathological changes. We used the filter-type gene selection algorithm based on t-statistics conjugated with the SVM classifier, and achieved a sensitivity of 90% with a selectivity of 90%. Then, 92 genes were extracted as the genomic biomarker candidates that were used to construct the classifier. The gene list contains well-known biomarkers, such as Kidney injury molecule 1, Ceruloplasmin, Clusterin, Tissue inhibitor of metallopeptidase 1, and also novel biomarker candidates. Most of the genes involved in tissue remodeling, the immune/inflammatory response, cell adhesion/proliferation/migration, and metabolism were predominantly up-regulated. Down-regulated genes participated in cell adhesion/proliferation/migration, membrane transport, and signal transduction. Our classifier has better prediction accuracy than any of the well-known biomarkers. Therefore, the toxicogenomics approach would be useful for concurrent diagnosis of renal tubular injury.

  1. Hemodynamic and renal implications of sodium-glucose cotransporter- 2 inhibitors in type 2 diabetes mellitus.

    Science.gov (United States)

    Tejedor Jorge, Alberto

    2016-11-01

    In DM2, there is increased expression of the proximal glucose transporter SGLT2. The increased glucose reabsorption from the urine to the proximal tubule and subsequently to the bloodstream, has three direct effects on the prognosis of patients with DM2: a) it increases the daily glucose load by raising the renal threshold for glucose, thus augmenting requirements for oral antidiabetics and insulin. This progressive increase occurs throughout the course of the disease and in parallel with the increase in renal mass (renal hypertrophy); b) because of the greater glucose reabsorption, glycosuria is lower than the level corresponding to glycaemia, decreasing the stimulus on the tubuloglomerular feedback system of the distal nephron. As a result, the glomerular vasodilation caused by hyperglycaemia is not arrested, maintaining glomerular hyperfiltration, and c) the excess glucose transported to the proximal tubular cells modifies their redox status, increasing local production of glycosylating products and activating local production of proinflammatory and profibrotic proliferative mediators. These mediators are responsible for the direct free radical damage to proximal tubular cells, for increased SGLT2 expression, increased production of collagen IV and extracellular matrix, and activation of monocyte/macrophages able to cause endothelial injury. The use of SGLT2 inhibitors not only reduces the reabsorption of glucose from the glomerular filtrate back into the circulationthus improving metabolic control in diabetesbut also restores tubuloglomerular feedback by increasing glycosuria and distal urinary flow. However, the most notable effect is due to inhibition of glucose entry to the proximal tubular cells. Glycosuria is toxic to the kidney: it harms glucosetransporting cells, that is, the proximal cells, which contain SGLT2. In animal models, SGLT2 inhibition reduces local production of oxygen-free radicals, the formation of mesangial matrix and collagen IV

  2. Effects of sodium nitrite on renal function and blood pressure in hypertensive vs. healthy study participants

    DEFF Research Database (Denmark)

    Rosenbæk, Jeppe B; Hornstrup, Bodil G; Jørgensen, Andreas N

    2018-01-01

    to determine the effects of NaNO2 on blood pressure (BP) and renal sodium and water regulation in patients with EHT compared with healthy control study participants (CON). METHODS: In a placebo-controlled, crossover study, we infused 240 μg NaNO2/kg/h or isotonic saline for 2 h in 14 EHT and 14 CON. During...... infusion, we measured changes in brachial and central BP, free water clearance, fractional sodium excretion, and urinary excretion rate of γ-subunit of the epithelial sodium channel (U-ENaCγ), and aquaporin-2 (U-AQP2). RESULTS: Placebo-adjusted brachial SBP decreased 18 mmHg (P ... infusion in EHT and 12 mmHg (P fractional sodium excretion, free water clearance, and U...

  3. Renal Blood Flow, Glomerular Filtration Rate, and Renal Oxygenation in Early Clinical Septic Shock.

    Science.gov (United States)

    Skytte Larsson, Jenny; Krumbholz, Vitus; Enskog, Anders; Bragadottir, Gudrun; Redfors, Bengt; Ricksten, Sven-Erik

    2018-06-01

    Data on renal hemodynamics, function, and oxygenation in early clinical septic shock are lacking. We therefore measured renal blood flow, glomerular filtration rate, renal oxygen consumption, and oxygenation in patients with early septic shock. Prospective comparative study. General and cardiothoracic ICUs. Patients with norepinephrine-dependent early septic shock (n = 8) were studied within 24 hours after arrival in the ICU and compared with postcardiac surgery patients without acute kidney injury (comparator group, n = 58). None. Data on systemic hemodynamics and renal variables were obtained during two 30-minute periods. Renal blood flow was measured by the infusion clearance of para-aminohippuric acid, corrected for renal extraction of para-aminohippuric acid. Renal filtration fraction was measured by renal extraction of chromium-51 labeled EDTA. Renal oxygenation was estimated from renal oxygen extraction. Renal oxygen delivery (-24%; p = 0.037) and the renal blood flow-to-cardiac index ratio (-21%; p = 0.018) were lower, renal vascular resistance was higher (26%; p = 0.027), whereas renal blood flow tended to be lower (-19%; p = 0.068) in the septic group. Glomerular filtration rate (-32%; p = 0.006) and renal sodium reabsorption (-29%; p = 0.014) were both lower in the septic group. Neither renal filtration fraction nor renal oxygen consumption differed significantly between groups. Renal oxygen extraction was significantly higher in the septic group (28%; p = 0.022). In the septic group, markers of tubular injury were elevated. In early clinical septic shock, renal function was lower, which was accompanied by renal vasoconstriction, a lower renal oxygen delivery, impaired renal oxygenation, and tubular sodium reabsorption at a high oxygen cost compared with controls.

  4. Metabolic and hemodynamic effects of sodium-dependent glucose cotransporter 2 inhibitors on cardio-renal protection in the treatment of patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Kashiwagi, Atsunori; Maegawa, Hiroshi

    2017-07-01

    The specific sodium-glucose cotransporter 2 inhibitors (SGLT2 inhibitors) inhibit glucose reabsorption in proximal renal tubular cells, and both fasting and postprandial glucose significantly decrease because of urinary glucose loss. As a result, pancreatic β-cell function and peripheral insulin action significantly improve with relief from glucose toxicity. Furthermore, whole-body energy metabolism changes to relative glucose deficiency and triggers increased lipolysis in fat cells, and fatty acid oxidation and then ketone body production in the liver during treatment with SGLT2 inhibitors. In addition, SGLT2 inhibitors have profound hemodynamic effects including diuresis, dehydration, weight loss and lowering blood pressure. The most recent findings on SGLT2 inhibitors come from results of the Empagliflozin, Cardiovascular Outcomes and Mortality in Type 2 Diabetes trial. SGLT2 inhibitors exert extremely unique and cardio-renal protection through metabolic and hemodynamic effects, with long-term durability on the reduction of blood glucose, bodyweight and blood pressure. Although a site of action of SGLT2 inhibitors is highly specific to inhibit renal glucose reabsorption, whole-body energy metabolism, and hemodynamic and renal functions are profoundly modulated during the treatment of SGLT2 inhibitors. Previous studies suggest multifactorial clinical benefits and safety concerns of SGLT2 inhibitors. Although ambivalent clinical results of this drug are still under active discussion, the present review summarizes promising recent evidence on the cardio-renal and metabolic benefits of SGLT2 inhibitors in the treatment of type 2 diabetes. © 2017 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

  5. Servo-control of water and sodium homeostasis during renal clearance measurements in conscious rats.

    Science.gov (United States)

    Thomsen, Klaus; Shirley, David G

    2007-01-01

    Servo-controlled fluid and sodium replacement during clearance studies is used in order to prevent loss of body fluid and sodium following diuretic/natriuretic procedures. However, even under control conditions, the use of this technique is sometimes associated with increases in proximal tubular fluid output (assessed by lithium clearance) and excretion rates. The present study examined the reason for these increases. The first series of experiments showed that one cause is volume overloading. This can occur if the servo system is activated from the start, i.e., during the establishment of a suitably high urine flow rate by constant infusion of hypotonic glucose solution. The second series of experiments showed that replacement of blood samples with donor blood can also lead to increases in fractional lithium excretion and accompanying increases in water and sodium excretion, a problem not seen when blood samples are replaced with the animal's own red blood cells resuspended in isotonic saline. When these pitfalls are avoided, servo-controlled sodium and fluid replacement is a reliable technique that makes it possible to study the effects of natriuretic and/or diuretic stimuli without interference from unwanted changes in extracellular volume. 2007 S. Karger AG, Basel

  6. Prediction of the overall renal tubular secretion and hepatic clearance of anionic drugs and a renal drug-drug interaction involving organic anion transporter 3 in humans by in vitro uptake experiments.

    Science.gov (United States)

    Watanabe, Takao; Kusuhara, Hiroyuki; Watanabe, Tomoko; Debori, Yasuyuki; Maeda, Kazuya; Kondo, Tsunenori; Nakayama, Hideki; Horita, Shigeru; Ogilvie, Brian W; Parkinson, Andrew; Hu, Zhuohan; Sugiyama, Yuichi

    2011-06-01

    The present study investigated prediction of the overall renal tubular secretion and hepatic clearances of anionic drugs based on in vitro transport studies. The saturable uptake of eight drugs, most of which were OAT3 substrates (rosuvastatin, pravastatin, pitavastatin, valsartan, olmesartan, trichlormethiazide, p-aminohippurate, and benzylpenicillin) by freshly prepared human kidney slices underestimated the overall intrinsic clearance of the tubular secretion; therefore, a scaling factor of 10 was required for in vitro-in vivo extrapolation. We examined the effect of gemfibrozil and its metabolites, gemfibrozil glucuronide and the carboxylic metabolite, gemfibrozil M3, on pravastatin uptake by human kidney slices. The inhibition study using human kidney slices suggests that OAT3 plays a predominant role in the renal uptake of pravastatin. Comparison of unbound concentrations and K(i) values (1.5, 9.1, and 4.0 μM, for gemfibrozil, gemfibrozil glucuronide, and gemfibrozil M3, respectively) suggests that the mechanism of the interaction is due mainly to inhibition by gemfibrozil and gemfibrozil glucuronide. Furthermore, extrapolation of saturable uptake by cryopreserved human hepatocytes predicts clearance comparable with the observed hepatic clearance although fluvastatin and rosuvastatin required a scaling factor of 11 and 6.9, respectively. This study suggests that in vitro uptake assays using human kidney slices and hepatocytes provide a good prediction of the overall tubular secretion and hepatic clearances of anionic drugs and renal drug-drug interactions. It is also recommended that in vitro-in vivo extrapolation be performed in animals to obtain more reliable prediction.

  7. [Influence of non-sodium restricted diet with diuretics on plasma rennin, renal blood flow and in patients with cirrhotic ascites].

    Science.gov (United States)

    Zhu, Yin-fang; Gu, Xi-bing; Zhu, Hong-ying; Yang, Xiao-juan; Wang, Dong; Yu, Ping

    2013-02-01

    To explore influence of sodium restricted diet and non-sodium restricted diet on plasma rennin (PRA), angiotensin II (All), ALD, renal blood flow (RBF) and subside of ascites in patients with cirrhotic ascites. Eighty cases of hepatitis B with cirrhotic ascites were randomly divided into sodium restricted diet group and non-sodium restricted diet group. 39 cases were in non-sodium restricted diet group, taking sodium chloride 6500-8000 mg daily; 41 cases were in sodium restricted diet group, taking sodium chloride 5000 mg daily. Both groups received diuretics furosemide and spironolactone. Blood sodium, urine sodium, PRA, AII, ALD, RBF ascites subsiding were compared after treatment. In non-sodium restricted diet group, blood sodium and urine sodium increased 10 days after treatment compared with those before treatment, and compared with those of sodium restricted diet group 10 days after treatment, P Renal damage induced by low blood sodium after treatment was less in non-sodium restricted diet group than that in sodium restricted diet group, P blood sodium, thus increasing excretion of urine sodium and diuretic effect. It can also decrease levels of PRA, AII and ALD, increase renal blood flow and prevent renal damage induced by low blood sodium and facilitate subsiding of ascites.

  8. Kidney injury after sodium phosphate solution beyond the acute renal failure.

    Science.gov (United States)

    Fernández-Juárez, Gema; Parejo, Leticia; Villacorta, Javier; Tato, Ana; Cazar, Ramiro; Guerrero, Carmen; Marin, Isabel Martinez; Ocaña, Javier; Mendez-Abreu, Angel; López, Katia; Gruss, Enrique; Gallego, Eduardo

    2016-01-01

    Screening colonoscopy with polipectomy reduces colonorectal cancer incidence and mortality. An adequate bowel cleansing is one of the keys to achieving best results with this technique. Oral sodium phosphate solution (OSP) had a widespread use in the 90s decade. Its efficacy was similar to polyethylene glycol (PEG) solution, but with less cost and convenient administration. Series of patients with acute renal failure due to OSP use have been reported. However, large cohorts of patients found no difference in the incidence of renal damage between these two solutions. From 2006 to 2009 we identified twelve cases of phosphate nephropathy after colonoscopy prepared with OSP. All patients were followed up to six months. All patients had received just a single dose. We analyzed 12 cases with phosphate nephropathy; three patients debuted with AKI and nine patients had chronic renal injury. Four cases were confirmed with renal biopsy. One patient with AKI needed hemodialysis at diagnosis without subsequent recovery. Two patients (both with chronic damage) fully recovered their previous renal function. The remaining patients (nine) had an average loss of estimated glomerular filtration rate of 24ml/min/1.73m(2). The use of OSP can lead to both acute and chronic renal damage. However, chronic injury was the most common pattern. Both forms of presentation imply a significant and irreversible loss of renal function. Further studies analyzing renal damage secondary to bowel cleaning should consider these two different patterns of injury. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  9. Effect of all-trans retinoic acid treatment on prohibitin and renin-angiotensin-aldosterone system expression in hypoxia-induced renal tubular epithelial cell injury.

    Science.gov (United States)

    Zhou, Tian-Biao; Ou, Chao; Rong, Liang; Drummen, Gregor P C

    2014-09-01

    All-trans retinoic acid (ATRA) exerts various effects on physiological processes such as cell growth, differentiation, apoptosis and inflammation. Prohibitins (PHB), including prohibitin 1 (PHB1) and prohibitin 2 (PHB2), are evolutionary conserved and pleiotropic proteins implicated in various cellular functions, including proliferation, tumor suppression, apoptosis, transcription, and mitochondrial protein folding. The renin-angiotensin-aldosterone system plays a pivotal role in the regulation of blood pressure and volume homeostasis. All these factors and systems have been implicated in renal interstitial fibrosis. Therefore, the objective of this study was to investigate the effect of ATRA treatment on the renin-angiotensin-aldosterone system and expression of prohibitins to further understand its role in the processes leading to renal interstitial fibrosis. The hypoxic and oxidative stress conditions in obstructive renal disease were simulated in a hypoxia/reoxygenation model with renal tubular epithelial cells (RTEC) as a model system. Subsequently, the effect of ATRA on mRNA and protein expression levels was determined and correlations were established between factors involved in the renin-angiotensin-aldosterone system, the prohibitins, cellular redox status, renal interstitial fibrosis and ATRA treatment. Correlation analysis showed that both PHB1 and PHB2 protein levels were negatively correlated with angiotensin I, ACE1, angiotensin II, TGF-β1, Col-IV, FN, ROS, and MDA (PHB1: r = -0.792, -0.834, -0.805, -0.795, -0.778, -0.798, -0.751, -0.682; PHB2: r = -0.872, -0.799, -0.838, -0.773, -0.769, -0.841, -0.794, -0.826; each p system under hypoxia/reoxygenation conditions. © The Author(s) 2014.

  10. Lipopolysaccharide-induced acute renal failure in conscious rats

    DEFF Research Database (Denmark)

    Jonassen, Thomas E N; Graebe, Martin; Promeneur, Dominique

    2002-01-01

    In conscious, chronically instrumented rats we examined 1) renal tubular functional changes involved in lipopolysaccharide (LPS)-induced acute renal failure; 2) the effects of LPS on the expression of selected renal tubular water and sodium transporters; and 3) effects of milrinone......-alpha and lactate, inhibited the LPS-induced tachycardia, and exacerbated the acute LPS-induced fall in GFR. Furthermore, Ro-20-1724-treated rats were unable to maintain MAP. We conclude 1) PDE3 or PDE4 inhibition exacerbates LPS-induced renal failure in conscious rats; and 2) LPS treated rats develop an escape......, a phosphodiesterase type 3 (PDE3) inhibitor, and Ro-20-1724, a PDE4 inhibitor, on LPS-induced changes in renal function. Intravenous infusion of LPS (4 mg/kg b.wt. over 1 h) caused an immediate decrease in glomerular filtration rate (GFR) and proximal tubular outflow without changes in mean arterial pressure (MAP...

  11. Does the renin-angiotensin system determine the renal and systemic hemodynamic response to sodium in patients with essential hypertension?

    NARCIS (Netherlands)

    vanPaassen, P; deZeeuw, D; Navis, G; deJong, PE

    Many patients with essential hypertension respond to a high dietary sodium intake with a rise in blood pressure. Experimental evidence suggests that the renal hemodynamic response to sodium determines, at least partially, this rise in blood pressure. Our aim was to clarify the role of the

  12. Resveratrol prevents high glucose-induced epithelial-mesenchymal transition in renal tubular epithelial cells by inhibiting NADPH oxidase/ROS/ERK pathway.

    Science.gov (United States)

    He, Ting; Guan, Xu; Wang, Song; Xiao, Tangli; Yang, Ke; Xu, Xinli; Wang, Junping; Zhao, Jinghong

    2015-02-15

    Resveratrol (RSV) is reported to have renoprotective activity against diabetic nephropathy, while the mechanisms underlying its function have not been fully elucidated. In this study, we investigate the effect and related mechanism of RSV against high glucose-induced epithelial to mesenchymal transition (EMT) in human tubular epithelial cells (HK-2). A typical EMT is induced by high glucose in HK-2 cells, accompanied by increased levels of reactive oxygen species (ROS). RSV exhibits a strong ability to inhibit high glucose-induced EMT by decreasing intracellular ROS levels via down-regulation of NADPH oxidase subunits NOX1 and NOX4. The activation of extracellular signal-regulated kinase (ERK1/2) is found to be involved in high glucose-induced EMT in HK-2 cells. RSV, like NADPH oxidase inhibitor diphenyleneiodonium, can block ERK1/2 activation induced by high glucose. Our results demonstrate that RSV is a potent agent against high glucose-induced EMT in renal tubular cells via inhibition of NADPH oxidase/ROS/ERK1/2 pathway. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Total mercury levels in hair, toenail, and urine among women free from occupational exposure and their relations to renal tubular function

    International Nuclear Information System (INIS)

    Ohno, Tomoko; Sakamoto, Mineshi; Kurosawa, Tomoko; Dakeishi, Miwako; Iwata, Toyoto; Murata, Katsuyuki

    2007-01-01

    To investigate the relations among total mercury levels in hair, toenail, and urine, together with potential effects of methylmercury intake on renal tubular function, we determined their levels, and urinary N-acetyl-β-d-glucosaminidase activity (NAG) and α 1 -microglobulin (AMG) in 59 women free from occupational exposures, and estimated daily mercury intakes from fish and other seafood using a food frequency questionnaire. Mercury levels (mean+/-SD) in the women were 1.51+/-0.91μg/g in hair, 0.59+/-0.32μg/g in toenail, and 0.86+/-0.66μg/g creatinine in urine; and, there were positive correlations among them (P<0.001). The daily mercury intake of 9.15+/-7.84μg/day was significantly correlated with total mercury levels in hair, toenail, and urine (r=0.551, 0.537, and 0.604, P<0.001). Among the women, the NAG and AMG were positively correlated with both the daily mercury intake and mercury levels in hair, toenail, and urine (P<0.01); and, these relations were almost similar when using multiple regression analysis to adjust for possible confounders such as urinary cadmium (0.47+/-0.28μg/g creatinine) and smoking status. In conclusion, mercury resulting from fish consumption can explain total mercury levels in hair, toenail, and urine to some degree (about 30%), partly through the degradation into the inorganic form, and it may confound the renal tubular effect of other nephrotoxic agents. Also, the following equation may be applicable to the population neither with dental amalgam fillings nor with occupational exposures: [hair mercury (μg/g)]=2.44x[toenail mercury (μg/g)

  14. Transforming growth factor-β-sphingosine kinase 1/S1P signaling upregulates microRNA-21 to promote fibrosis in renal tubular epithelial cells.

    Science.gov (United States)

    Liu, Xiujuan; Hong, Quan; Wang, Zhen; Yu, Yanyan; Zou, Xin; Xu, Lihong

    2016-02-01

    Renal fibrosis is a progressive pathological change characterized by tubular cell apoptosis, tubulointerstitial fibroblast proliferation, and excessive deposition of extracellular matrix (ECM). miR-21 has been implicated in transforming growth factor-β (TGF-β)-stimulated tissue fibrosis. Recent studies showed that sphingosine kinase/sphingosine-1-phosphate (SphK/S1P) are also critical for TGF-β-stimulated tissue fibrosis; however, it is not clear whether SphK/S1P interacts with miR-21 or not. In this study, we hypothesized that SphK/S1P signaling is linked to upregulation of miR-21 by TGF-β. To verify this hypothesis, we first determined that miR-21 was highly expressed in renal tubular epithelial cells (TECs) stimulated with TGF-β by using qRT-PCR and Northern blotting. Simultaneously, inhibition of miR-21, mediated by the corresponding antimir, markedly decreased the expression and deposition of type I collagen, fibronectin (Fn), cysteine-rich protein 61 (CCN1), α-smooth muscle actin, and fibroblast-specific protein1 in TGF-β-treated TECs. ELISA and qRT-PCR were used to measure the S1P and SphK1 levels in TECs. S1P production was induced by TGF-β through activation of SphK1. Furthermore, it was observed that TGF-β-stimulated upregulation of miR-21 was abolished by SphK1 siRNA and was restored by the addition of exogenous S1P. Blocking S1PR2 also inhibited upregulation of miR-21. Additionally, miR-21 overexpression attenuated the repression of TGF-β-stimulated ECM deposition and epithelial-mesenchymal transition by SphK1 and S1PR2 siRNA. In summary, our study demonstrates a link between SphK1/S1P and TGF-β-induced miR-21 in renal TECs and may represent a novel therapeutic target in renal fibrosis. © 2015 by the Society for Experimental Biology and Medicine.

  15. Peripheral arterial vasodilation hypothesis: a proposal for the initiation of renal sodium and water retention in cirrhosis

    DEFF Research Database (Denmark)

    Schrier, R W; Arroyo, V; Bernardi, M

    1988-01-01

    Renal sodium and water retention and plasma volume expansion have been shown to precede ascites formation in experimental cirrhosis. The classical "underfilling" theory, in which ascites formation causes hypovolemia and initiates secondary renal sodium and water retention, thus seems unlikely...... with cirrhosis. Arterial vasodilators and arteriovenous fistula are other examples in which renal sodium and water retention occur secondary to a decreased filling of the arterial vascular tree. An increase in cardiac output and hormonal stimulation are common features of cirrhosis, arteriovenous fistula...... and drug-induced peripheral arterial vasodilation. However, a predilection for the retained sodium and water to transudate into the abdominal cavity occurs with cirrhosis because of the presence of portal hypertension. The Peripheral Arterial Vasodilation Hypothesis also explains the continuum from...

  16. Altered regulation of renal sodium transporters in salt-sensitive hypertensive rats induced by uninephrectomy.

    Science.gov (United States)

    Jung, Ji Yong; Lee, Jay Wook; Kim, Sejoong; Jung, Eun Sook; Jang, Hye Ryoun; Han, Jin Suk; Joo, Kwon Wook

    2009-12-01

    Uninephrectomy (uNx) in young rats causes salt-sensitive hypertension (SSH). Alterations of sodium handling in residual nephrons may play a role in the pathogenesis. Therefore, we evaluated the adaptive alterations of renal sodium transporters according to salt intake in uNx-SSH rats. uNx or sham operations were performed in male Sprague-Dawley rats, and normal-salt diet was fed for 4 weeks. Four experimental groups were used: sham-operated rats raised on a high-salt diet for 2 weeks (CHH) or on a low-salt diet for 1 week after 1 week's high-salt diet (CHL) and uNx rats fed on the same diet (NHH, NHL) as the sham-operated rats were fed. Expression of major renal sodium transporters were determined by semiquantitative immunoblotting. Systolic blood pressure was increased in NHH and NHL groups, compared with CHH and CHL, respectively. Protein abundances of Na(+)/K(+)/2Cl(-) cotransporter (NKCC2) and Na(+)/Cl(-) cotransporter (NCC) in the CHH group were lower than the CHL group. Expression of epithelial sodium channel (ENaC)-γ increased in the CHH group. In contrast, expressions of NKCC2 and NCC in the NHH group didn't show any significant alterations, compared to the NHL group. Expressions of ENaC-α and ENaC-β in the NHH group were higher than the CHH group. Adaptive alterations of NKCC2 and NCC to changes of salt intake were different in the uNx group, and changes in ENaC-α and ENaC-β were also different. These altered regulations of sodium transporters may be involved in the pathogenesis of SSH in the uNx rat model.

  17. A longitudinal study on urinary cadmium and renal tubular protein excretion of nickel-cadmium battery workers after cessation of cadmium exposure.

    Science.gov (United States)

    Gao, Yanhua; Zhang, Yanfang; Yi, Juan; Zhou, Jinpeng; Huang, Xianqing; Shi, Xinshan; Xiao, Shunhua; Lin, Dafeng

    2016-10-01

    This study aimed to predict the outcome of urinary cadmium (Cd) excretion and renal tubular function by analyzing their evolution through 10 years after Cd exposure ceased. Forty-one female, non-smoking workers were recruited from the year 2004 to 2009 when being removed from a nickel-cadmium battery factory, and they were asked to provide morning urine samples on three consecutive days at enrollment and in every follow-up year until 2014. Urinary Cd and renal tubular function biomarkers including urinary β2-microglobulin (β2-m) and retinol-binding protein (RBP) concentrations were determined with the graphite furnace atomic absorption spectrometry and the enzyme-linked immunosorbent assays, respectively. The medians of baseline Cd, β2-m and RBP concentrations at enrollment were 6.19, 105.38 and 71.84 μg/g creatinine, respectively. Urinary β2-m and RBP concentrations were both related to Cd concentrations over the years (β absolute-β2-m = 9.16, P = 0.008 and β absolute-RBP = 6.42, P < 0.001, respectively). Cd, β2-m and RBP concentrations in the follow-up years were all associated with their baseline concentrations (β absolute-Cd = 0.61, P < 0.001; β absolute-β2-m = 0.64, P < 0.001; and β absolute-RBP = 0.60, P < 0.001, respectively), and showed a decreasing tendency with the number of elapsed years relative to their baseline concentrations (β relative-Cd = -0.20, P = 0.010; β relative-β2-m = -17.19, P = 0.002; and β relative-RBP = -10.66, P < 0.001, respectively). Urinary Cd might eventually decrease to the general population level, and Cd-related tubular function would improve under the baseline conditions of this cohort.

  18. Selective renal vasoconstriction, exaggerated natriuresis and excretion rates of exosomic proteins in essential hypertension

    DEFF Research Database (Denmark)

    Damkjaer, M.; Jensen, Pia Hønnerup; Schwämmle, Veit

    2014-01-01

    AimIn essential hypertension (EH), the regulation of renal sodium excretion is aberrant. We hypothesized that in mild EH, (i) abnormal dynamics of plasma renin concentration (PRC) and atrial natriuretic peptide (ANP) are responsible for the exaggerated natriuresis, and (ii) exosomic protein...... patterns reflect the renal tubular abnormality involved in the dysregulation of sodium excretion. MethodsAfter 2-week drug washout and 4-day diet, systemic and renal hemodynamics, cardio-renal hormones, glomerular filtration and renal excretion were studied in male patients during saline loading (SL...

  19. Dietary Sodium Modulation of Aldosterone Activation and Renal Function During the Progression of Experimental Heart Failure Miller: Dietary Sodium and Early Heart Failure

    Science.gov (United States)

    Miller, Wayne L.; Borgeson, Daniel D.; Grantham, J. Aaron; Luchner, Andreas; Redfield, Margaret M.; Burnett, John C.

    2015-01-01

    Aims Aldosterone activation is central to the sodium-fluid retention that marks the progression of heart failure (HF). The actions of dietary sodium restriction, a mainstay in HF management, on cardiorenal and neuroendocrine adaptations during the progression of HF are poorly understood. The study aim was to assess the role of dietary sodium during the progression of experimental HF. Methods and Results Experimental HF was produced in a canine model by rapid right ventricular pacing which evolves from early mild HF to overt, severe HF. Dogs were fed one of three diets: 1) high sodium [250 mEq (5.8 grams) per day, n=6]; 2) standard sodium [58 mEq (1.3 grams) per day, n=6]; and 3) sodium restriction [11 mEq (0.25 grams) per day, n=6]. During the 38 day study hemodynamics, renal function, renin activity (PRA), and aldosterone were measured. Changes in hemodynamics at 38 days were similar in all three groups, as were changes in renal function. Aldosterone activation was demonstrated in all three groups, however, dietary sodium restriction, in contrast to high sodium, resulted in early (10 days) activation of PRA and aldosterone. High sodium demonstrated significant suppression of aldosterone activation over the course of HF progression. Conclusions Excessive dietary sodium restriction particularly in early stage HF results in early aldosterone activation, while normal and excess sodium intake are associated with delayed or suppressed activation. These findings warrant evaluation in humans to determine if dietary sodium manipulation, particularly during early stage HF, may have a significant impact on neuroendocrine disease progression. PMID:25823360

  20. Toxicological Significance of Renal Bcrp: Another Potential Transporter in the Elimination of Mercuric Ions from Proximal Tubular Cells

    Science.gov (United States)

    Bridges, Christy C.; Zalups, Rudolfs K.; Joshee, Lucy

    2015-01-01

    Secretion of inorganic mercury (Hg2+) from proximal tubular cells into the tubular lumen has been shown to involve the multidrug resistance-associated protein 2 (Mrp2). Considering similarities in localization and substrate specificity between Mrp2 and the breast cancer resistance protein (Bcrp), we hypothesize that Bcrp may also play a role in the proximal tubular secretion of mercuric species. In order to test this hypothesis, the uptake of Hg2+ was examined initially using inside-out membrane vesicles containing Bcrp. The results of these studies suggest that Bcrp may be capable of transporting certain conjugates of Hg2+. To further characterize the role of Bcrp in the handling of mercuric ions and in the induction of Hg2+-induced nephropathy, Sprague-Dawley and Bcrp knockout (bcrp−/−) rats were exposed intravenously to a non-nephrotoxic (0.5 μmol • kg−1), a moderately nephrotoxic (1.5 μmol • kg−1) or a significantly nephrotoxic (2.0 μmol • kg−1) dose of HgCl2. In general, the accumulation of Hg2+ was greater in organs of bcrp−/− rats than in Sprague-Dawley rats, suggesting that Bcrp may play a role in the export of Hg2+ from target cells. Within the kidney, cellular injury and necrosis was more severe in bcrp−/− rats than in controls. The pattern of necrosis, which was localized in the inner cortex and the outer stripe of the outer medulla was significantly different from that observed in Mrp2-deficient animals. These findings suggest that Bcrp may be involved in the cellular export of select mercuric species and that its role in this export may differ from that of Mrp2. PMID:25868844

  1. Toxicological significance of renal Bcrp: Another potential transporter in the elimination of mercuric ions from proximal tubular cells

    Energy Technology Data Exchange (ETDEWEB)

    Bridges, Christy C., E-mail: bridges_cc@mercer.edu; Zalups, Rudolfs K.; Joshee, Lucy

    2015-06-01

    Secretion of inorganic mercury (Hg{sup 2+}) from proximal tubular cells into the tubular lumen has been shown to involve the multidrug resistance-associated protein 2 (Mrp2). Considering similarities in localization and substrate specificity between Mrp2 and the breast cancer resistance protein (Bcrp), we hypothesize that Bcrp may also play a role in the proximal tubular secretion of mercuric species. In order to test this hypothesis, the uptake of Hg{sup 2+} was examined initially using inside-out membrane vesicles containing Bcrp. The results of these studies suggest that Bcrp may be capable of transporting certain conjugates of Hg{sup 2+}. To further characterize the role of Bcrp in the handling of mercuric ions and in the induction of Hg{sup 2+}-induced nephropathy, Sprague–Dawley and Bcrp knockout (bcrp{sup −/−}) rats were exposed intravenously to a non-nephrotoxic (0.5 μmol·kg{sup −1}), a moderately nephrotoxic (1.5 μmol·kg{sup −1}) or a significantly nephrotoxic (2.0 μmol·kg{sup −1}) dose of HgCl{sub 2}. In general, the accumulation of Hg{sup 2+} was greater in organs of bcrp{sup −/−} rats than in Sprague–Dawley rats, suggesting that Bcrp may play a role in the export of Hg{sup 2+} from target cells. Within the kidney, cellular injury and necrosis was more severe in bcrp{sup −/−} rats than in controls. The pattern of necrosis, which was localized in the inner cortex and the outer stripe of the outer medulla, was significantly different from that observed in Mrp2-deficient animals. These findings suggest that Bcrp may be involved in the cellular export of select mercuric species and that its role in this export may differ from that of Mrp2. - Highlights: • Bcrp may mediate transport of mercury out of proximal tubular cells. • Hg-induced nephropathy was more severe in Bcrp knockout rats. • Bcrp and Mrp2 may differ in their ability to transport Hg.

  2. Sodium hypochlorite-induced acute kidney injury

    Directory of Open Access Journals (Sweden)

    Brandon W Peck

    2014-01-01

    Full Text Available Sodium hypochlorite (bleach is commonly used as an irrigant during dental proce-dures as well as a topical antiseptic agent. Although it is generally safe when applied topically, reports of accidental injection of sodium hypochlorite into tissue have been reported. Local necrosis, pain and nerve damage have been described as a result of exposure, but sodium hypo-chlorite has never been implicated as a cause of an acute kidney injury (AKI. In this report, we describe the first case of accidental sodium hypochlorite injection into the infraorbital tissue during a dental procedure that precipitated the AKI. We speculate that oxidative species induced by sodium hypochlorite caused AKI secondary to the renal tubular injury, causing mild acute tubular necrosis.

  3. Four siblings with distal renal tubular acidosis and nephrocalcinosis, neurobehavioral impairment, short stature, and distinctive facial appearance: a possible new autosomal recessive syndrome.

    Science.gov (United States)

    Faqeih, Eissa; Al-Akash, Samhar I; Sakati, Nadia; Teebi, Prof Ahmad S

    2007-09-01

    We report on four siblings (three males, one female) born to first cousin Arab parents with the constellation of distal renal tubular acidosis (RTA), small kidneys, nephrocalcinosis, neurobehavioral impairment, short stature, and distinctive facial features. They presented with early developmental delay with subsequent severe mental, behavioral and social impairment and autistic-like features. Their facial features are unique with prominent cheeks, well-defined philtrum, large bulbous nose, V-shaped upper lip border, full lower lip, open mouth with protruded tongue, and pits on the ear lobule. All had proteinuria, hypercalciuria, hypercalcemia, and normal anion-gap metabolic acidosis. Renal ultrasound examinations revealed small kidneys, with varying degrees of hyperechogenicity and nephrocalcinosis. Additional findings included dilated ventricles and cerebral demyelination on brain imaging studies. Other than distal RTA, common causes of nephrocalcinosis were excluded. The constellation of features in this family currently likely represents a possibly new autosomal recessive syndrome providing further evidence of heterogeneity of nephrocalcinosis syndromes. Copyright 2007 Wiley-Liss, Inc.

  4. Preliminary study on application of urine amino acids profiling for monitoring of renal tubular injury using GLC-MS

    Directory of Open Access Journals (Sweden)

    Maja Kazubek-Zemke

    2014-11-01

    Full Text Available The early diagnosis of the nephrotoxic effect of xenobiotics and drugs is still an unsolved problem. Recent studies suggest a correlation between the nephrotoxic activity of xenobiotics and increased concentration of amino acids in urine. The presented study was focused on the application of GLC-MS method for amino acids profiling in human urine as a noninvasive method for monitoring of kidney condition and tubular injury level.The analytic method is based on the conversion of the amino acids present in the sample to tert-butyldimethylsilyl (TBDMS derivatives and their analysis by gas-liquid chromatography-mass spectrometry (GLC-MS. The procedure of urine sample preparation for chromatographic analysis was optimized.The presence of 12 amino acids in most of the tested healthy human urine samples was detected. The significant differences in the levels of particular amino acids between patients with tubular injury and healthy controls were found, especially for lysine, valine, serine, alanine and leucine (on average 30.0, 7.5, 3.6, 2.9 and 0.5 fold respectively.We found that this approach based on GLC-MS detection can be used in nephrotoxicity studies for urine amino acids monitoring in exposure to xenobiotics and drugs.

  5. Preliminary study on application of urine amino acids profiling for monitoring of renal tubular injury using GLC-MS.

    Science.gov (United States)

    Kazubek-Zemke, Maja; Rybka, Jacek; Marchewka, Zofia; Rybka, Wojciech; Pawlik, Krzysztof; Długosz, Anna

    2014-11-14

    The early diagnosis of the nephrotoxic effect of xenobiotics and drugs is still an unsolved problem. Recent studies suggest a correlation between the nephrotoxic activity of xenobiotics and increased concentration of amino acids in urine. The presented study was focused on the application of GLC-MS method for amino acids profiling in human urine as a noninvasive method for monitoring of kidney condition and tubular injury level. The analytic method is based on the conversion of the amino acids present in the sample to tert-butyldimethylsilyl (TBDMS) derivatives and their analysis by gas-liquid chromatography-mass spectrometry (GLC-MS). The procedure of urine sample preparation for chromatographic analysis was optimized. The presence of 12 amino acids in most of the tested healthy human urine samples was detected. The significant differences in the levels of particular amino acids between patients with tubular injury and healthy controls were found, especially for lysine, valine, serine, alanine and leucine (on average 30.0, 7.5, 3.6, 2.9 and 0.5 fold respectively). We found that this approach based on GLC-MS detection can be used in nephrotoxicity studies for urine amino acids monitoring in exposure to xenobiotics and drugs.

  6. Urotensin II Induces ER Stress and EMT and Increase Extracellular Matrix Production in Renal Tubular Epithelial Cell in Early Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Xin-Xin Pang

    2016-07-01

    Full Text Available Background/Aims: Urotensin II (UII and its receptor are highly expressed in the kidney tissue of patients with diabetic nephropathy (DN. The aim of this study is to examine the roles of UII in the induction of endoplasmic reticulum stress (ER stress and Epithelial-mesenchymal transition (EMT in DN in vivo and in vitro. Methods: Kidney tissues were collected from patients with DN. C57BL/6 mice and mice with UII receptor knock out were injected with two consecutive doses of streptozotocin to induce diabetes and were sacrificed at 3th week for in vivo study. HK-2 cells in vitro were cultured and treated with UII. Markers of ER stress and EMT, fibronectin and type IV collagen were detected by immunohistochemistry, real time PCR and western blot. Results: We found that the expressions of protein of UII, GRP78, CHOP, ALPHA-SMA, fibronectin and type IV collagen were upregulated while E-cadherin protein was downregulated as shown by immunohistochemistry or western blot analysis in kidney of diabetic mice in comparison to normal control; moreover expressions of GRP78, CHOP, ALPHA-SMA, fibronectin and type IV collagen were inhibited while E-caherin expression was enhanced in kidney in diabetic mice with UII receptor knock out in comparison to C57BL/6 diabetic mice. In HK-2 cells, UII induced upregulation of GRP78, CHOP, ALPHA-SMA, fibroblast-specifc protein 1(FSP-1, fibronectin and type collagen and downregulation of E-cadherin. UII receptor antagonist can block UII-induced ER stress and EMT; moreover, 4-PBA can inhibit the mRNA expression of ALPHA-SMA and FSP1 induced by UII in HK-2 cells. Conclusions: We are the first to verify UII induces ER stress and EMT and increase extracellular matrix production in renal tubular epithelial cell in early diabetic mice. Moreover, UII may induce renal tubular epithelial EMT via triggering ER stress pathway in vitro, which might be the new pathogenic pathway for the development of renal fibrosis in DN.

  7. Chronic nitric oxide synthase inhibition exacerbates renal dysfunction in cirrhotic rats

    DEFF Research Database (Denmark)

    Graebe, M.; Brond, L.; Christensen, S.

    2004-01-01

    The present study investigated sodium balance and renal tubular function in cirrhotic rats with chronic blockade of the nitric oxide (NO) system. Rats were treated with the nonselective NO synthase inhibitor NG-nitro-l-arginine methyl ester (l-NAME) starting on the day of common bile duct ligation...... (CBL). Three weeks of daily sodium balance studies showed that CBL rats developed sodium retention compared with sham-operated rats and that l-NAME treatment dose dependently deteriorated cumulative sodium balance by reducing urinary sodium excretion. Five weeks after CBL, renal clearance studies were...

  8. The role of perioperative sodium bicarbonate infusion affecting renal function after Cardiothoracic Surgery

    Directory of Open Access Journals (Sweden)

    Katja Regina Turner

    2014-06-01

    Full Text Available Cardiac surgery associated acute kidney injury (CSA-AKI is associated with poor outcomes including increased mortality, length of hospital stay and cost. The incidence of acute kidney injury (AKI is reported to be between 3-30% depending on the definition of AKI. We designed a multicenter randomized controlled trial to test our hypothesis that a perioperative infusion of sodium bicarbonate during cardiac surgery will attenuate the postoperative rise in creatinine indicating renal injury when compared to a perioperative infusion with normal saline. An interim analysis was performed after data was available on the first 120 participants. A similar number of patients in the two treatment groups developed acute kidney injury (AKI, defined as an increase in serum creatinine the first 48 hours after surgery of 0.3 mg/dl or more. Specifically 14 patients (24% who received sodium chloride (SC and 17 patients (27% who received sodium bicarbonate (SB were observed to develop AKI post surgery, resulting in a relative risk of AKI of 1.1 (95% CI: 0.6-2.1, chi-square p-value=0.68 for patients receiving SB compared to those who received SC . The data safety monitoring board for the trial recommended closing the study early as there was only a 12% probability that the null hypothesis would be rejected. We therefore concluded that a perioperative infusion of sodium bicarbonate failed to attenuate the risk of CSA-AKI.

  9. MiR-30c regulates cisplatin-induced apoptosis of renal tubular epithelial cells by targeting Bnip3L and Hspa5.

    Science.gov (United States)

    Du, Bin; Dai, Xiao-Meng; Li, Shuang; Qi, Guo-Long; Cao, Guang-Xu; Zhong, Ying; Yin, Pei-di; Yang, Xue-Song

    2017-08-10

    As a common anticancer drug, cisplatin has been widely used for treating tumors in the clinic. However, its side effects, especially its nephrotoxicity, noticeably restrict the application of cisplatin. Therefore, it is imperative to investigate the mechanism of renal injury and explore the corresponding remedies. In this study, we showed the phenotypes of the renal tubules and epithelial cell death as well as elevated cleaved-caspase3- and TUNEL-positive cells in rats intraperitoneally injected with cisplatin. Similar cisplatin-induced cell apoptosis was found in HK-2 and NRK-52E cells exposed to cisplatin as well. In both models of cisplatin-induced apoptosis in vivo and in vitro, quantitative PCR data displayed reductions in miR-30a-e expression levels, indicating that miR-30 might be involved in regulating cisplatin-induced cell apoptosis. This was further confirmed when the effects of cisplatin-induced cell apoptosis were found to be closely correlated with alterations in miR-30c expression, which were manipulated by transfection of either the miR-30c mimic or miR-30c inhibitor in HK-2 and NRK-52E cells. Using bioinformatics tools, including TargetScan and a gene expression database (Gene Expression Omnibus), Adrb1, Bnip3L, Hspa5 and MAP3K12 were predicted to be putative target genes of miR-30c in cisplatin-induced apoptosis. Subsequently, Bnip3L and Hspa5 were confirmed to be the target genes after determining the expression of these putative genes following manipulation of miR-30c expression levels in HK-2 cells. Taken together, our current experiments reveal that miR-30c is certainly involved in regulating the renal tubular cell apoptosis induced by cisplatin, which might supply a new strategy to minimize cisplatin-induced nephrotoxicity.

  10. The significance of determination of renal tubular markers before and after treatment in the primary nephrotic syndrome

    International Nuclear Information System (INIS)

    Xie Bing; Jiang Liping

    2011-01-01

    Objective: To evaluate the damage of renal tubule of patients with primary nephrotic syndrome (PNS) by detecting renal tubule markers and investigate the significance of different therapeutic effects. Methods: Serum levels of interleukin-6(IL-6), ET-1, α 1 -microglobulin(α 1 -m), β 2 -microglobulin(β 2 -m) and plasma level of ET-1 were determined with RIA, fibrinogen degradation product (FDP) with ELISA, automatic biochemistry analysis N-acetyl-β-D-glucosaminidase(NAG), CH 2 O was determined with physico-method respectively. Results: The concentrations of IL-6, ET-1, α 1 -m, β 2 -m, FDP, NAG were significantly decreased in cases of complete remission after therapy (P 2 O excepted (P>0.05), the decrease of IL-6, ET-1, α 1 -m, FDP were no significant in cases of invalid (P>0.05), the concentrations of renal tubule markers in cases of partial remission and invalid were higher than those in cases of complete and significant remission. Conclusion: The determination of several renal tubule markers can be used for diagnose, monitor and judge the therapeutic effects of PNS. (authors)

  11. Increased renal sodium absorption by inhibition of prostaglandin synthesis during fasting in healthy man. A possible role of the epithelial sodium channels

    Directory of Open Access Journals (Sweden)

    Graffe Carolina C

    2010-10-01

    Full Text Available Abstract Background Treatment with prostaglandin inhibitors can reduce renal function and impair renal water and sodium excretion. We tested the hypotheses that a reduction in prostaglandin synthesis by ibuprofen treatment during fasting decreased renal water and sodium excretion by increased absorption of water and sodium via the aquaporin2 water channels and the epithelial sodium channels. Methods The effect of ibuprofen, 600 mg thrice daily, was measured during fasting in a randomized, placebo-controlled, double-blinded crossover study of 17 healthy humans. The subjects received a standardized diet on day 1, fasted at day 2, and received an IV infusion of 3% NaCl on day 3. The effect variables were urinary excretions of aquaporin2 (u-AQP2, the beta-fraction of the epithelial sodium channel (u-ENaCbeta, cyclic-AMP (u-cAMP, prostaglandin E2 (u-PGE2. Free water clearance (CH2O, fractional excretion of sodium (FENa, and plasma concentrations of vasopressin, angiotensin II, aldosterone, atrial-, and brain natriuretic peptide. Results Ibuprofen decreased u-AQP2, u-PGE2, and FENa at all parts of the study. During the same time, ibuprofen significantly increased u-ENaCbeta. Ibuprofen did not change the response in p-AVP, u-c-AMP, urinary output, and free water clearance during any of these periods. Atrial-and brain natriuretic peptide were higher. Conclusion During inhibition of prostaglandin synthesis, urinary sodium excretion decreased in parallel with an increase in sodium absorption and increase in u-ENaCbeta. U-AQP2 decreased indicating that water transport via AQP2 fell. The vasopressin-c-AMP-axis did not mediate this effect, but it may be a consequence of the changes in the natriuretic peptide system and/or the angiotensin-aldosterone system Trial Registration Clinical Trials Identifier: NCT00281762

  12. MRP-1 expression levels determine strain-specific susceptibility to sodium arsenic-induced renal injury between C57BL/6 and BALB/c mice

    International Nuclear Information System (INIS)

    Kimura, Akihiko; Ishida, Yuko; Wada, Takashi; Yokoyama, Hitoshi; Mukaida, Naofumi; Kondo, Toshikazu

    2005-01-01

    To clarify the pathophysiological mechanism underlying acute renal injury caused by acute exposure to arsenic, we subcutaneously injected both BALB/c and C57BL/6 mice with sodium arsenite (NaAs; 13.5 mg/kg). BALB/c mice exhibited exaggerated elevation of serum blood urea nitrogen (BUN) and creatinine (CRE) levels, compared with C57BL/6 mice. Moreover, half of BALB/c mice died by 24 h, whereas all C57BL/6 mice survived. Histopathological examination on kidney revealed severe hemorrhages, acute tubular necrosis, neutrophil infiltration, cast formation, and disappearance of PAS-positive brush borders in BALB/c mice, later than 10 h. These pathological changes were remarkably attenuated in C57BL/6 mice, accompanied with lower intrarenal arsenic concentrations, compared with BALB/c mice. Among heavy metal inducible proteins including multidrug resistance-associated protein (MRP)-1, multidrug resistance gene (MDR)-1, metallothionein (MT)-1, and arsenite inducible, cysteine- and histidine-rich RNA-associated protein (AIRAP), intrarenal MDR-1, MT-1, and AIRAP gene expression was enhanced to a similar extent in both strains, whereas NaAs challenge augmented intrarenal MRP-1 mRNA and protein expression levels in C57BL/6 but not BALB/c mice. Moreover, the administration of a specific inhibitor of MRP-1, MK-571, significantly exaggerated acute renal injury in C57BL/6 mice. Thus, MRP-1 is crucially involved in arsenic efflux and eventually prevention of acute renal injury upon acute exposure to NaAs

  13. High maternal sodium intake alters sex-specific renal renin-angiotensin system components in newborn Wistar offspring.

    Science.gov (United States)

    Maia, D R R; Lopes, K L; Heimann, J C; Furukawa, L N S

    2016-01-28

    This study aimed to evaluate the systemic and renal renin-angiotensin-aldosterone system (RAAS) at birth in male and female offspring and in mothers fed a high sodium diet (HSD) before and during gestation. Female Wistar rats were fed a HSD (8.0% NaCl) or a normal sodium diet (1.3% NaCl) from 8 weeks of age until delivery of their first litter. Maternal body weight, tail blood pressure, and food and water intake were evaluated. The litter sizes were assessed, and the body and kidney weights of the offspring were measured. Both mothers and offspring were euthanized immediately following the birth of the pups to evaluate plasma renin activity (PRA), renal renin content (RRC), renal angiotensin-converting enzyme (ACE) activity, renal angiotensin (Ang) II content, serum aldosterone (ALDO) levels, and renal cortical and medullary renin messenger RNA expression. In mothers in the HSD group, water intake and kidney mass were higher, whereas renal ACE activity, Ang II, PRA, ALDO and RRC were decreased. In the offspring of HSD-fed dams, the body and kidney mass were lower in both genders, renal ACE activity was lower in females and renal Ang II was lower in males. PRA, RRC, renin gene expression and ALDO levels did not differ between the groups of offspring. The data presented herein showed that a maternal HSD during pregnancy induces low birth weight and a sex-specific response in the RAAS in offspring.

  14. Predictors of mortality and the provision of dialysis in patients with acute tubular necrosis. The Auriculin Anaritide Acute Renal Failure Study Group.

    Science.gov (United States)

    Chertow, G M; Lazarus, J M; Paganini, E P; Allgren, R L; Lafayette, R A; Sayegh, M H

    1998-04-01

    To explore the natural history of critically ill patients with acute renal failure due to acute tubular necrosis, we evaluated 256 patients enrolled in the placebo arm of a randomized clinical trial. Death and the composite outcome, death or the provision of dialysis, were determined with follow-up to 60 d. The relative risks (RR) and 95% confidence intervals (95% CI) associated with routinely available demographic, clinical, and laboratory variables were estimated using proportional hazards regression. Ninety-three (36%) deaths were documented; an additional 52 (20%) patients who survived received dialysis. Predictors of mortality included male gender (RR, 2.01; 95% CI, 1.21 to 3.36), oliguria (RR, 2.25; 95% CI, 1.43 to 3.55), mechanical ventilation (RR, 1.86; 95% CI, 1.18 to 2.93), acute myocardial infarction (RR, 3.14; 95% CI, 1.85 to 5.31), acute stroke or seizure (RR, 3.08; 95% CI, 1.56 to 6.06), chronic immunosuppression (RR, 2.37; 95% CI, 1.16 to 4.88), hyperbilirubinemia (RR, 1.06; 95% CI, 1.03 to 1.08 per 1 mg/dl increase in total bilirubin) and metabolic acidosis (RR, 0.95; 95% CI, 0.90 to 0.99 per 1 mEq/L increase in serum bicarbonate concentration). Predictors of death or the provision of dialysis were oliguria (RR, 5.95; 95% CI, 3.96 to 8.95), mechanical ventilation (RR, 1.53; 95% CI, 1.07 to 2.21), acute myocardial infarction (RR, 1.95; 95% CI, 1.24 to 3.07), arrhythmia (RR, 1.51; 95% CI, 1.04 to 2.19), and hypoalbuminemia (RR, 0.56; 95% CI, 0.42 to 0.74 per 1 g/dl increase in serum albumin concentration). Neither mortality nor the provision of dialysis was related to patient age. These observations can be used to estimate risk early in the course of acute tubular necrosis. Furthermore, these and related models may be used to adjust for case-mix variation in quality improvement efforts, and to objectively stratify patients in future intervention trials aimed at favorably altering the course of hospital-acquired acute renal failure.

  15. Effects of Sodium Selenite on Formaldehyde Induced Renal Toxicity in Mice

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    Shabnam Mohammadi 1,2 * , Maryam Moghimian 3, Hanieh Torabzadeh 4, Mahla Langari 4, Roghayeh Nazeri 4, Zahra Karimi 4, Elham Sangari 4, Najmeh Jagarmi 5, Alireza Mohammad Zadeh 3, Mehdi Karimi 7, Kamyar Tavakkoli 8, Ali Delshad 9, Fatemeh Mohammadzadeh 3, Majid Ghayour-Mobarhan 10

    2016-12-01

    Full Text Available Background: Formaldehyde is widely used for industrial applications. Renal injury is an adverse effect associated with formaldehyde. Few studies have explored the potential benefits of protective factors on formaldehyde induced renal toxicity. This study evaluated the dose dependent effects of sodium selenite on the biochemical and histopathological effects of formaldehyde on murine kidney. Methods: Forty eight adult Balb/c male mice were randomized into six groups: a control group, a formaldehyde group and experimental III-VI groups. Formaldehyde group was injected with 10 mg/kg formaldehyde and groups III-VI received intraperitoneally doses of 0.1, 0.2, 0.4, 0.8 mg/kg selenium. After two weeks, a stereological study was done in accordance with the principle of Cavalieri and serum concentrations of urea and creatinine were measured. Data were analyzed using ANOVA and SPSS software. Results: Glomerosclerosis, necrosis and vacuolization were observed in the convoluted tubules of animals treated with formaldehyde. The biochemical markers, volume and count of glomeruli in the group treated with formaldehyde was significantly difference compared to the control group (P<0.05. The volume of the glomeruli in the group treated with 0.2 and 0.4 mg selenium and urea level in the group treated with 0.4 and 0.1 mg/kg selenium was significantly difference compared to the control group (P <0.05. The count of glomeruli and creatinine level in the selenium group was significantly difference compared to the control group (P ≤ 0.0001. Conclusions: A dose of 0.2 mg/kg of sodium selenite caused partial protective effect on the renal tissue and function in exposed to formaldehyde.

  16. Tubular combustion

    CERN Document Server

    Ishizuka, Satoru

    2014-01-01

    Tubular combustors are cylindrical tubes where flame ignition and propagation occur in a spatially confined, highly controlled environment, in a nearly flat, elongated geometry. This allows for some unique advantages where extremely even heat dispersion is required over a large surface while still maintaining fuel efficiency. Tubular combustors also allow for easy flexibility in type of fuel source, allowing for quick changeover to meet various needs and changing fuel pricing. This new addition to the MP sustainable energy series will provide the most up-to-date research on tubular combustion--some of it only now coming out of private proprietary protection. Plentiful examples of current applications along with a good explanation of background theory will offer readers an invaluable guide on this promising energy technology. Highlights include: * An introduction to the theory of tubular flames * The "how to" of maintaining stability of tubular flames through continuous combustion * Examples of both small-scal...

  17. Measurement of renal blood flow by 131I-labelled sodium iodohippurate imaging in a rat model of herpes encephalitis

    International Nuclear Information System (INIS)

    Cleator, G.M.; Klapper, P.E.; Lewis, A.G.; Sharma, H.L.; Smith, A.M.; Manchester Univ.

    1990-01-01

    Renal blood flow was assessed qualitatively over a 30 min period in a rat model of herpes encephalitis by extra-renal scintigraphic imaging following the injection of 131 I-labelled sodium iodohippurate. No significant differences were observed for renal blood flow in either kidney between (or within) infected and control groups. Our data suggest that kidney function is not compromised in this animal model of encephalitis. The results are discussed in the context of the development of a non-invasive protocol for the in vivo diagnosis of herpes encephalitis. (orig.)

  18. Leptin Induces Oxidative Stress Through Activation of NADPH Oxidase in Renal Tubular Cells: Antioxidant Effect of L-Carnitine.

    Science.gov (United States)

    Blanca, Antonio J; Ruiz-Armenta, María V; Zambrano, Sonia; Salsoso, Rocío; Miguel-Carrasco, José L; Fortuño, Ana; Revilla, Elisa; Mate, Alfonso; Vázquez, Carmen M

    2016-10-01

    Leptin is a protein involved in the regulation of food intake and in the immune and inflammatory responses, among other functions. Evidences demonstrate that obesity is directly associated with high levels of leptin, suggesting that leptin may directly link obesity with the elevated cardiovascular and renal risk associated with increased body weight. Adverse effects of leptin include oxidative stress mediated by activation of NADPH oxidase. The aim of this study was to evaluate the effect of L-carnitine (LC) in rat renal epithelial cells (NRK-52E) exposed to leptin in order to generate a state of oxidative stress characteristic of obesity. Leptin increased superoxide anion (O2 (•) -) generation from NADPH oxidase (via PI3 K/Akt pathway), NOX2 expression and nitrotyrosine levels. On the other hand, NOX4 expression and hydrogen peroxide (H2 O2 ) levels diminished after leptin treatment. Furthermore, the expression of antioxidant enzymes, catalase, and superoxide dismutase, was altered by leptin, and an increase in the mRNA expression of pro-inflammatory factors was also found in leptin-treated cells. LC restored all changes induced by leptin to those levels found in untreated cells. In conclusion, stimulation of NRK-52E cells with leptin induced a state of oxidative stress and inflammation that could be reversed by preincubation with LC. Interestingly, LC induced an upregulation of NOX4 and restored the release of its product, hydrogen peroxide, which suggests a protective role of NOX4 against leptin-induced renal damage. J. Cell. Biochem. 117: 2281-2288, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  19. [3H]AVP binding to rat renal tubular receptors during long-term treatment with an antagonist of arginine vasopressin

    International Nuclear Information System (INIS)

    Mah, S.C.; Whitebread, S.E.; De Gasparo, M.; Hofbauer, K.G.

    1988-01-01

    The interaction of an antagonist of arginine vasopressin (AVP), d(CH2)5-D-Tyr(Et)VAVP, with renal tubular V2 receptors were studied in medullary membrane preparations from kidneys of Sprague-Dawley and Brattleboro rats. In both rat strains, V2 receptors had comparable KD and Bmax values for binding of [3H]AVP. In vitro studies revealed that the V2-antagonist was more potent than cold AVP in displacing [3H]AVP. In vivo treatment of Sprague-Dawley rats with the antagonist over one week resulted only in a transient state of diabetes insipidus (DI). No specific [3H]AVP binding was detectable throughout the period of administration. Chronic treatment of Brattleboro rats resulted in a complete normalization of water intake. This agonistic effect was also associated with undetectable [3H]AVP binding. After stopping the infusion of d(CH2)5-D-Tyr(Et)VAVP, Bmax values tended to rise but had still not reached base line values after 6 days. In contrast, the chronic infusion of AVP in Brattleboro rats resulted in a reduction in water intake which was accompanied by a decreased Bmax. [3H]AVP binding remained detectable during the entire treatment period. Thereafter Bmax was restored to base line values within 2 days of stopping the infusion. These results suggest that d(CH2)5-D-Tyr(Et)VAVP has a high affinity for V2 receptors in both Sprague-Dawley and Brattleboro rats. Its rate of dissociation from the receptor appears to be much slower than that of AVP. In Brattleboro rats, the binding of d(CH2)5-D-Tyr(Et)VAVP leads to an antidiuretic response. In Sprague-Dawley rats, a transient diuretic response is followed by a progressive normalization in water intake. This occurs despite persistent and complete blockade of renal medullary V2 receptors

  20. Hypokalemic muscular paralysis causing acute respiratory failure due to rhabdomyolysis with renal tubular acidosis in a chronic glue sniffer.

    Science.gov (United States)

    Kao, K C; Tsai, Y H; Lin, M C; Huang, C C; Tsao, C Y; Chen, Y C

    2000-01-01

    A 34-year-old male was admitted to the emergency department with the development of quadriparesis and respiratory failure due to hypokalemia after prolonged glue sniffing. The patient was subsequently given mechanical ventilatory support for respiratory failure. He was weaned from the ventilator 4 days later after potassium replacement. Toluene is an aromatic hydrocarbon found in glues, cements, and solvents. It is known to be toxic to the nervous system, hematopoietic system, and causes acid-base and electrolyte disorders. Acute respiratory failure with hypokalemia and rhabdomyolysis with acute renal failure should be considered as potential events in a protracted glue sniffing.

  1. Contribution of the organic anion transporter OAT2 to the renal active tubular secretion of creatinine and mechanism for serum creatinine elevations caused by cobicistat.

    Science.gov (United States)

    Lepist, Eve-Irene; Zhang, Xuexiang; Hao, Jia; Huang, Jane; Kosaka, Alan; Birkus, Gabriel; Murray, Bernard P; Bannister, Roy; Cihlar, Tomas; Huang, Yong; Ray, Adrian S

    2014-08-01

    Many xenobiotics including the pharmacoenhancer cobicistat increase serum creatinine by inhibiting its renal active tubular secretion without affecting the glomerular filtration rate. This study aimed to define the transporters involved in creatinine secretion, applying that knowledge to establish the mechanism for xenobiotic-induced effects. The basolateral uptake transporters organic anion transporter OAT2 and organic cation transporters OCT2 and OCT3 were found to transport creatinine. At physiologic creatinine concentrations, the specific activity of OAT2 transport was over twofold higher than OCT2 or OCT3, establishing OAT2 as a likely relevant creatinine transporter and further challenging the traditional view that creatinine is solely transported by a cationic pathway. The apical multidrug and toxin extrusion transporters MATE1 and MATE2-K demonstrated low-affinity and high-capacity transport. All drugs known to affect creatinine inhibited OCT2 and MATE1. Similar to cimetidine and ritonavir, cobicistat had the greatest effect on MATE1 with a 50% inhibition constant of 0.99 μM for creatinine transport. Trimethoprim potently inhibited MATE2-K, whereas dolutegravir preferentially inhibited OCT2. Cimetidine was unique, inhibiting all transporters that interact with creatinine. Thus, the clinical observation of elevated serum creatinine in patients taking cobicistat is likely a result of OCT2 transport, facilitating intracellular accumulation, and MATE1 inhibition.

  2. Contribution of the organic anion transporter OAT2 to the renal active tubular secretion of creatinine and mechanism for serum creatinine elevations caused by cobicistat

    Science.gov (United States)

    Lepist, Eve-Irene; Zhang, Xuexiang; Hao, Jia; Huang, Jane; Kosaka, Alan; Birkus, Gabriel; Murray, Bernard P; Bannister, Roy; Cihlar, Tomas; Huang, Yong; Ray, Adrian S

    2014-01-01

    Many xenobiotics including the pharmacoenhancer cobicistat increase serum creatinine by inhibiting its renal active tubular secretion without affecting the glomerular filtration rate. This study aimed to define the transporters involved in creatinine secretion, applying that knowledge to establish the mechanism for xenobiotic-induced effects. The basolateral uptake transporters organic anion transporter OAT2 and organic cation transporters OCT2 and OCT3 were found to transport creatinine. At physiologic creatinine concentrations, the specific activity of OAT2 transport was over twofold higher than OCT2 or OCT3, establishing OAT2 as a likely relevant creatinine transporter and further challenging the traditional view that creatinine is solely transported by a cationic pathway. The apical multidrug and toxin extrusion transporters MATE1 and MATE2-K demonstrated low-affinity and high-capacity transport. All drugs known to affect creatinine inhibited OCT2 and MATE1. Similar to cimetidine and ritonavir, cobicistat had the greatest effect on MATE1 with a 50% inhibition constant of 0.99 μM for creatinine transport. Trimethoprim potently inhibited MATE2-K, whereas dolutegravir preferentially inhibited OCT2. Cimetidine was unique, inhibiting all transporters that interact with creatinine. Thus, the clinical observation of elevated serum creatinine in patients taking cobicistat is likely a result of OCT2 transport, facilitating intracellular accumulation, and MATE1 inhibition. PMID:24646860

  3. Renal Subcapsular Transplantation of PSC-Derived Kidney Organoids Induces Neo-vasculogenesis and Significant Glomerular and Tubular Maturation In Vivo

    Directory of Open Access Journals (Sweden)

    Cathelijne W. van den Berg

    2018-03-01

    Full Text Available Summary: Human pluripotent stem cell (hPSC-derived kidney organoids may facilitate disease modeling and the generation of tissue for renal replacement. Long-term application, however, will require transferability between hPSC lines and significant improvements in organ maturation. A key question is whether time or a patent vasculature is required for ongoing morphogenesis. Here, we show that hPSC-derived kidney organoids, derived in fully defined medium conditions and in the absence of any exogenous vascular endothelial growth factor, develop host-derived vascularization. In vivo imaging of organoids under the kidney capsule confirms functional glomerular perfusion as well as connection to pre-existing vascular networks in the organoids. Wide-field electron microscopy demonstrates that transplantation results in formation of a glomerular basement membrane, fenestrated endothelial cells, and podocyte foot processes. Furthermore, compared with non-transplanted organoids, polarization and segmental specialization of tubular epithelium are observed. These data demonstrate that functional vascularization is required for progressive morphogenesis of human kidney organoids. : In this article, Van den Berg and colleagues show that PSC-derived kidney organoids contain nephron structures but remain disorganized and immature after prolonged culture. Upon transplantation, the organoids develop host-derived vascularization, functional glomerular perfusion, and connection to pre-existing vascular networks. The authors conclude that patent vasculature is required for ongoing morphogenesis and maturation of these kidney organoids. Keywords: human pluripotent stem cells, directed differentiation, kidney organoids, transplantation, intravital microscopy, vascularization, maturation

  4. Contrast Media-Induced Renal Inflammation Is Mediated Through HMGB1 and Its Receptors in Human Tubular Cells.

    Science.gov (United States)

    Guan, Xiao-Feng; Chen, Qing-Jie; Zuo, Xiao-Cong; Guo, Ren; Peng, Xiang-Dong; Wang, Jiang-Lin; Yin, Wen-Jun; Li, Dai-Yang

    2017-01-01

    With the rapid development of imaging diagnosis and interventional therapy, contrast media (CM) are widely used in clinics. However, contrast-induced nephropathy (CIN) is the third leading cause of hospital-acquired acute renal failure accounting for 10-12% of all causes of hospital-acquired renal failure. Recent study found that inflammation may participate in the pathogenesis of CIN, but the role of it remains unclear. HK-2 cells were treated with Iohexol, Urografin, and mannitol. Two types of CM increased the release of HMGB1 in cell supernatant accompanied by increased expression of TLR2 and CXCR4. Iohexol and Urografin also caused a significant increase in NF-κB followed by the release of IL-6 and MCP-1. To clarify the role of HMGB1, TLR2, and CXCR4, glycyrrhizin, anti-TLR2-IgG, and AMD3100 were used to inhibit HMGB1, TLR2, and CXCR4, respectively. Significant decrease in the expression of TLR2, CXCR4, nuclear NF-κB, and the release of IL-6 and MCP-1 were observed. These results indicate that TLR2 and CXCR4 signaling are involved in CM-induced HK-2 cell injury model in an HMGB1-dependent pathway, which may provide a new target for the prevention and the treatment of CIN.

  5. Na+ pump in renal tubular cells is regulated by endogenous Na+-K+-ATPase inhibitor from hypothalamus

    International Nuclear Information System (INIS)

    Cantiello, H.F.; Chen, E.; Ray, S.; Haupert, G.T. Jr.

    1988-01-01

    Bovine hypothalamus contains a high affinity, specific, reversible inhibitor of mammalian Na + -K + -ATPase. Kinetic analysis using isolated membrane fractions showed binding and dissociation rates of the hypothalamic factor (HF) to be (like ouabain) relatively long (off rate = 60 min). To determine whether the kinetics of inhibition in intact cells might be more consistent with regulation of physiological processes in vivo, binding and dissociation reactions of HF in intact renal epithelial cells (LLC-PK 1 ) were studied using 86 Rb + uptake and [ 3 H]ouabain binding. As with membranes, a 60-min incubation with HF inhibited Na + -K + -ATPase in LLC-PK 1 cells. In contrast to membrane studies, no prolonged incubation with LLC-PK 1 was needed to observe inhibition of Na + -K + -ATPase. HF caused a 33% inhibition of ouabain-sensitive 86 Rb + influx within 10 min. Incubation of cells with HF followed by washout showed rapid reversal of pump inhibition and a doubling of pump activity. The dose-response curve for HF inhibition of LLC-PK 1 86 Rb + uptake showed a sigmoidal shape consistent with an allosteric binding reaction. Thus HF is a potent regulator of Na + -K + -ATPase activity in intact renal cells, with binding and dissociation reactions consistent with relevant physiological processes

  6. Na sup + pump in renal tubular cells is regulated by endogenous Na sup + -K sup + -ATPase inhibitor from hypothalamus

    Energy Technology Data Exchange (ETDEWEB)

    Cantiello, H.F.; Chen, E.; Ray, S.; Haupert, G.T. Jr. (Harvard medical School, Boston, MA (USA))

    1988-10-01

    Bovine hypothalamus contains a high affinity, specific, reversible inhibitor of mammalian Na{sup +}-K{sup +}-ATPase. Kinetic analysis using isolated membrane fractions showed binding and dissociation rates of the hypothalamic factor (HF) to be (like ouabain) relatively long (off rate = 60 min). To determine whether the kinetics of inhibition in intact cells might be more consistent with regulation of physiological processes in vivo, binding and dissociation reactions of HF in intact renal epithelial cells (LLC-PK{sup 1}) were studied using {sup 86}Rb{sup +} uptake and ({sup 3}H)ouabain binding. As with membranes, a 60-min incubation with HF inhibited Na{sup +}-K{sup +}-ATPase in LLC-PK{sub 1} cells. In contrast to membrane studies, no prolonged incubation with LLC-PK{sub 1} was needed to observe inhibition of Na{sup +}-K{sup +}-ATPase. HF caused a 33% inhibition of ouabain-sensitive {sup 86}Rb{sup +} influx within 10 min. Incubation of cells with HF followed by washout showed rapid reversal of pump inhibition and a doubling of pump activity. The dose-response curve for HF inhibition of LLC-PK{sub 1} {sup 86}Rb{sup +} uptake showed a sigmoidal shape consistent with an allosteric binding reaction. Thus HF is a potent regulator of Na{sup +}-K{sup +}-ATPase activity in intact renal cells, with binding and dissociation reactions consistent with relevant physiological processes.

  7. Management of oxidative stress by heme oxygenase-1 in cisplatin-induced toxicity in renal tubular cells.

    Science.gov (United States)

    Schaaf, G J; Maas, R F M; de Groene, E M; Fink-Gremmels, J

    2002-08-01

    Induction of heme oxygenase-1 (HO-1) may serve as an immediate protective response during treatment with the cytostatic drug cisplatin (CDDP). Oxidative pathways participate in the characteristic nephrotoxicity of CDDP. In the present study, cultured tubular cells (LLC-PK1) were used to investigate whether induction of HO provided protection against CDDP by maintaining the cellular redox balance. The antioxidants, alpha-tocopherol (TOCO) and N-acetylcysteine (NAC), were used to demonstrate that elevation of ROS levels contribute to the development of CDDP-induced cytotoxicity. Chemical modulators of HO activity were used to investigate the role of HO herein. Hemin was used to specifically induce HO-1, while exposure of the cells to tin-protoporphyrin (SnPP) was shown to inhibit HO activity. Hemin treatment prior to CDDP-exposure significantly decreased the generation of ROS to control levels, while inhibition of HO increased the ROS levels beyond the levels measured in cells treated with CDDP alone. Furthermore, HO induction protected significantly against the cytotoxicity of CDDP, although this protection was limited. Similar results were obtained when the cells were preincubated with TOCO, suggesting that mechanisms other than impairment of the redox ratio are important in CDDP-induced loss of cell viability in vitro. In addition, SnPP treatment exacerbated the oxidative response and cytotoxicity of CDDP, especially at low CDDP concentrations. We therefore conclude that HO is able to directly limit the CDDP-induced oxidative stress response and thus serves as safeguard of the cellular redox balance.

  8. Efecto citotóxico de la toxina shiga tipo 2 y su subunidad b en células epiteliales tubulares renales humanas en cultivo Cytotoxic effect of Shiga toxin type 2 and its B subunit on human renal tubular epithelial cell cultures

    Directory of Open Access Journals (Sweden)

    Virginia Pistone Creydt

    2005-04-01

    Full Text Available Escherichia coli enterohemorrágica productora de toxina Shiga (Stx causa diarrea acuosa, colitis hemorrágica y síndrome urémico hemolítico (SUH. En Argentina, el SUH es la principal causa de insuficiencia renal en niños. El objetivo de este trabajo fue estudiar la toxicidad de Stx tipo 2 (Stx2 y su subunidad B (Stx2B en células epiteliales tubulares renales humanas (CERH, en presencia y ausencia de factores inflamatorios. Los efectos citotóxicos se evaluaron como alteración de la funcionalidad del epitelio; daños histológicos; viabilidad celular; síntesis de proteínas y apoptosis celular. Los resultados muestran que Stx2 regula el pasaje de agua a través de CERH a tiempos menores de 1h de incubación. A tiempos mayores, hasta 72 hs, el estudio de la morfología, la viabilidad, la síntesis de proteínas y la apoptosis demostró que las CERH fueron sensibles a la acción citotóxica de Stx2 y Stx2B de una manera dosis y tiempo dependiente. Estos efectos fueron potenciados por lipopolisacáridos bacterianos (LPS, IL-1b, y butirato.Shiga toxin (Stx-producing E.coli causing watery diarrhea, hemorrhagic colitis and hemolytic-uremic syndrome (HUS. In Argentina, HUS is the most common cause of acute renal failure in children. The purpose of the present study was to examine the cytotoxicity of Stx type 2 (Stx2 and its B subunit (Stx2B on human renal tubular epithelial cells (HRTEC, in the presence and absence of inflammatory factors. Cytotoxic effects were assessed in terms of functionality of the epithelium, histological damage, cell viability, protein synthesis and cellular apoptosis. Results show that Stx2 regulates the passage of water through the HRTEC within an incubation period of 1h. Within longer periods, up to 72 hours, the study of morphology, viability, protein synthesis and apoptosis shows that HRTEC were sensitive to the cytotoxic action of Stx2 and Stx2B in a dose- and time-dependent manner. These effects were potentiated by

  9. Mechanisms of Contrast-Induced Nephropathy Reduction for Saline (NaCl and Sodium Bicarbonate (NaHCO3

    Directory of Open Access Journals (Sweden)

    W. Patrick Burgess

    2014-01-01

    Full Text Available Nephropathy following contrast media (CM exposure is reduced by administration before, during, and after the contrast procedure of either isotonic sodium chloride solution (Saline or isotonic sodium bicarbonate solution (IsoBicarb. The reasons for this reduction are not well established for either sodium salt; probable mechanisms are discussed in this paper. For Saline, the mechanism for the decrease in CIN is likely related primarily to the increased tubular flow rates produced by volume expansion and therefore a decreased concentration of the filtered CM during transit through the kidney tubules. Furthermore, increased tubular flow rates produce a slight increase in tubular pH resulting from a fixed acid excretion in an increased tubular volume. The mechanism for the decreased CIN associated with sodium bicarbonate includes the same mechanisms listed for Saline in addition to a renal pH effect. Increased filtered bicarbonate anion raises both tubular pH and tubular bicarbonate anion levels toward blood physiologic levels, thus providing increased buffer for reactive oxygen species (ROS formed in the tubules as a result of exposure to CM in renal tubular fluid.

  10. Renal glucose handling in diabetes and sodium glucose cotransporter 2 inhibition

    Directory of Open Access Journals (Sweden)

    Resham Raj Poudel

    2013-01-01

    Full Text Available The kidneys play a major role in glucose homeostasis through its utilization, gluconeogenesis, and reabsorption via sodium glucose cotransporters (SGLTs. The defective renal glucose handling from upregulation of SGLTs, mainly the SGLT2, plays a fundamental role in the pathogenesis of type 2 diabetes mellitus. Genetic mutations in a SGLT2 isoform that results in benign renal glycosuria, as well as clinical studies with SGLT2 inhibitors in type 2 diabetes support the potential of this approach. These studies indicate that inducing glycosuria by suppressing SGLT2 can reduce plasma glucose and A1c levels, as well as decrease weight, resulting in improved β-cell function and enhanced insulin sensitivity in liver and muscle. Because the mechanism of SGLT2 inhibition is independent of insulin secretion and sensitivity, these agents can be combined with other antidiabetic agents, including exogenous insulin. This class represents a novel therapeutic approach with potential for the treatment of both type 2 and type 1 diabetes.

  11. CNS sites activated by renal pelvic epithelial sodium channels (ENaCs) in response to hypertonic saline in awake rats.

    Science.gov (United States)

    Goodwill, Vanessa S; Terrill, Christopher; Hopewood, Ian; Loewy, Arthur D; Knuepfer, Mark M

    2017-05-01

    In some patients, renal nerve denervation has been reported to be an effective treatment for essential hypertension. Considerable evidence suggests that afferent renal nerves (ARN) and sodium balance play important roles in the development and maintenance of high blood pressure. ARN are sensitive to sodium concentrations in the renal pelvis. To better understand the role of ARN, we infused isotonic or hypertonic NaCl (308 or 500mOsm) into the left renal pelvis of conscious rats for two 2hours while recording arterial pressure and heart rate. Subsequently, brain tissue was analyzed for immunohistochemical detection of the protein Fos, a marker for neuronal activation. Fos-immunoreactive neurons were identified in numerous sites in the forebrain and brainstem. These areas included the nucleus tractus solitarius (NTS), the lateral parabrachial nucleus, the paraventricular nucleus of the hypothalamus (PVH) and the supraoptic nucleus (SON). The most effective stimulus was 500mOsm NaCl. Activation of these sites was attenuated or prevented by administration of benzamil (1μM) or amiloride (10μM) into the renal pelvis concomitantly with hypertonic saline. In anesthetized rats, infusion of hypertonic saline but not isotonic saline into the renal pelvis elevated ARN activity and this increase was attenuated by simultaneous infusion of benzamil or amiloride. We propose that renal pelvic epithelial sodium channels (ENaCs) play a role in activation of ARN and, via central visceral afferent circuits, this system modulates fluid volume and peripheral blood pressure. These pathways may contribute to the development of hypertension. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. alpha-Adducin mutations increase Na/K pump activity in renal cells by affecting constitutive endocytosis: implications for tubular Na reabsorption.

    Science.gov (United States)

    Torielli, Lucia; Tivodar, Simona; Montella, Rosa Chiara; Iacone, Roberto; Padoani, Gloria; Tarsini, Paolo; Russo, Ornella; Sarnataro, Daniela; Strazzullo, Pasquale; Ferrari, Patrizia; Bianchi, Giuseppe; Zurzolo, Chiara

    2008-08-01

    Genetic variation in alpha-adducin cytoskeletal protein is implicated in the polymerization and bundling of actin and alteration of the Na/K pump, resulting in abnormal renal sodium transport and hypertension in Milan hypertensive rats and humans. To investigate the molecular involvement of alpha-adducin in controlling Na/K pump activity, wild-type or mutated rat and human alpha-adducin forms were, respectively, transfected into several renal cell lines. Through multiple experimental approaches (microscopy, enzymatic assays, coimmunoprecipitation), we showed that rat and human mutated forms increased Na/K pump activity and the number of pump units; moreover, both variants coimmunoprecipitate with Na/K pump. The increased Na/K pump activity was not due to changes in its basolateral localization, but to an alteration of Na/K pump residential time on the plasma membrane. Indeed, both rat and human mutated variants reduced constitutive Na/K pump endocytosis and similarly affected transferrin receptor trafficking and fluid-phase endocytosis. In fact, alpha-adducin was detected in clathrin-coated vesicles and coimmunoprecipitated with clathrin. These results indicate that adducin, besides its modulatory effects on actin cytoskeleton dynamics, might play a direct role in clathrin-dependent endocytosis. The constitutive reduction of the Na/K pump endocytic rate induced by mutated adducin variants may be relevant in Na-dependent hypertension.

  13. Regulation of renal NaPi-2 expression and tubular phosphate reabsorption by growth hormone in the juvenile rat.

    Science.gov (United States)

    Woda, Craig B; Halaihel, Nabil; Wilson, Paul V; Haramati, Aviad; Levi, Moshe; Mulroney, Susan E

    2004-07-01

    Growth hormone (GH) is an important factor in the developmental adaptation to enhance P(i) reabsorption; however, the nephron sites and mechanisms by which GH regulates renal P(i) uptake remain unclear and are the focus of the present study. Micropuncture experiments were performed after acute thyroparathyroidectomy in the presence and absence of parathyroid hormone (PTH) in adult (14- to 17-wk old), juvenile (4-wk old), and GH-suppressed juvenile male rats. While the phosphaturic effect of PTH was blunted in the juvenile rat compared with the adult, suppression of GH in the juvenile restored fractional P(i) excretion to adult levels. In the presence or absence of PTH, GH suppression in the juvenile rat caused a significant increase in the fractional P(i) delivery to the late proximal convoluted (PCT) and early distal tubule, so that delivery was not different from that in adults. These data were confirmed by P(i) uptake studies into brush-border membrane (BBM) vesicles. Immunofluorescence studies indicate increased BBM type IIa NaP(i) cotransporter (NaPi-2) expression in the juvenile compared with adult rat, and GH suppression reduced NaPi-2 expression to levels observed in the adult. GH replacement in the [N-acetyl-Tyr(1)-d-Arg(2)]-GRF-(1-29)-NH(2)-treated juveniles restored high NaPi-2 expression and P(i) uptake. Together, these novel results demonstrate that the presence of GH in the juvenile animal is crucial for the early developmental upregulation of BBM NaPi-2 and, most importantly, describe the enhanced P(i) reabsorption along the PCT and proximal straight nephron segments in the juvenile rat.

  14. PGI2 synthesis and excretion in dog kidney: evidence for renal PG compartmentalization

    International Nuclear Information System (INIS)

    Boyd, R.M.; Nasjletti, A.; Heerdt, P.M.; Baer, P.G.

    1986-01-01

    To assess the concept of compartmentalization of renal prostaglandins (PG), we compared entry of PGE2 and the PGI2 metabolite 6-keto-PGF1 alpha into the renal vascular and tubular compartments, in sodium pentobarbital-anesthetized dogs. Renal arterial 6-keto-PGF1 alpha infusion increased both renal venous and urinary 6-keto-PGF1 alpha outflow. In contrast, renal arterial infusion of arachidonic acid (AA) or bradykinin (BK) increased renal venous 6-keto-PGF1 alpha outflow but had no effect on its urinary outflow. Both urinary and renal venous PGE2 outflows increased during AA or BK infusion. Ureteral stopped-flow studies revealed no postglomerular 6-keto-PGF1 alpha entry into tubular fluid. During renal arterial infusion of [3H]PGI2 and inulin, first-pass 3H clearance was 40% of inulin clearance; 35% of urinary 3H was 6-keto-PGF1 alpha, and two other urinary metabolites were found. During renal arterial infusion of [3H]6-keto-PGF1 alpha and inulin, first-pass 3H clearance was 150% of inulin clearance; 75% of urinary 3H was 6-keto-PGF1 alpha, and only one other metabolite was found. We conclude that in the dog PGE2 synthesized in the kidney enters directly into both the renal vascular and tubular compartments, but 6-keto-PGF1 alpha of renal origin enters directly into only the renal vascular compartment

  15. Crosstalk between Smad and Mitogen-Activated Protein Kinases for the Regulation of Apoptosis in Cyclosporine A- Induced Renal Tubular Injury

    Directory of Open Access Journals (Sweden)

    Hideyuki Iwayama

    2011-10-01

    Full Text Available Background/Aims: It remains elusive whether there is a crosstalk between Smad and mitogen-activated protein kinases (MAPKs and whether it regulates cyclosporine A (CyA-induced apoptosis in renal proximal tubular cells (RPTCs. Methods: The effect of CyA on nuclear translocation of Smad2/3 and MAPKs (measured by Western blotting or immunofluorescence and apoptosis (determined by Hoechst 33258 staining was examined in HK-2 cells. Results: CyA induced apoptosis at 24 h and nuclear translocation of phosphorylated (p-Smad2/3 at 3 h, which was continued till 24 h. CyA enhanced the expression of p-ERK at 1 h, which was continued till 24 h, and of p-p38MAPK at 1–6 h, which returned to control level at 12 h. CyA did not affect JNK. An inhibitor of ERK, PD98059, prevented CyA-induced nuclear translocation of Smad2/3 and apoptosis. An inhibitor of p38MAPK, SB202190, deteriorated CyA-induced nuclear translocation of p-Smad2/3. Epidermal growth factor (EGF activated ERK and p38MAPK but not JNK. EGF-induced activation of MAPKs ameliorated CyA-induced nuclear translocation of p-Smad2/3 and apoptosis. Inhibition of p38MAPK but not of ERK abolished the protective effect of EGF on CyA-induced nuclear translocation of p-Smad2/3 and apoptosis. Conclusion: Crosstalk between R-Smad and p38MAPK/ERK, but not JNK differentially regulates apoptosis in CyA-induced RPTC injury.

  16. Effects of insulin detemir and NPH insulin on renal handling of sodium, fluid retention and weight in type 2 diabetic patients

    DEFF Research Database (Denmark)

    Hendriksen, K V; Jensen, Tonny Joran; Oturai, P

    2012-01-01

    In type 2 diabetic patients, insulin detemir (B29Lys(ε-tetradecanoyl),desB30 human insulin) induces less weight gain than NPH insulin. Due to the proposed reduction of tubular action by insulin detemir, type 2 diabetic patients should have increased urinary sodium excretion, thereby reducing extr...

  17. Renal Development and Blood Pressure in Offspring from Dams Submitted to High-Sodium Intake during Pregnancy and Lactation

    Directory of Open Access Journals (Sweden)

    Terezila M. Coimbra

    2012-01-01

    Full Text Available Exposure to an adverse environment in utero appears to programme physiology and metabolism permanently, with long-term consequences for health of the fetus or offspring. It was observed that the offspring from dams submitted to high-sodium intake during pregnancy present disturbances in renal development and in blood pressure. These alterations were associated with lower plasma levels of angiotensin II (AII and changes in renal AII receptor I (AT1 and mitogen-activated protein kinase (MAPK expressions during post natal kidney development. Clinical and experimental evidence show that the renin-angiotensin system (RAS participates in renal development. Many effects of AII are mediated through MAPK pathways. Extracellular signal-regulated protein kinases (ERKs play a pivotal role in cellular proliferation and differentiation. In conclusion, high-sodium intake during pregnancy and lactation can provoke disturbances in renal development in offspring leading to functional and structural alterations that persist in adult life. These changes can be related at least in part with the decrease in RAS activity considering that this system has an important role in renal development.

  18. Increased renal alpha-epithelial sodium channel (ENAC) protein and increased ENAC activity in normal pregnancy.

    Science.gov (United States)

    West, Crystal; Zhang, Zheng; Ecker, Geoffrey; Masilamani, Shyama M E

    2010-11-01

    Pregnancy-mediated sodium (Na) retention is required to provide an increase in plasma volume for the growing fetus. The mechanisms responsible for this Na retention are not clear. We first used a targeted proteomics approach and found that there were no changes in the protein abundance compared with virgin rats of the β or γ ENaC, type 3 Na(+)/H(+) exchanger (NHE3), bumetanide-sensitive cotransporter (NKCC2), or NaCl cotransporter (NCC) in mid- or late pregnancy. In contrast, we observed marked increases in the abundance of the α-ENaC subunit. The plasma volume increased progressively during pregnancy with the greatest plasma volume being evident in late pregnancy. ENaC inhibition abolished the difference in plasma volume status between virgin and pregnant rats. To determine the in vivo activity of ENaC, we conducted in vivo studies of rats in late pregnancy (days 18-20) and virgin rats to measure the natriuretic response to ENaC blockade (with benzamil). The in vivo activity of ENaC (U(Na)V postbenzamil-U(Na)V postvehicle) was markedly increased in late pregnancy, and this difference was abolished by pretreatment with the mineralocorticoid receptor antagonist, eplerenone. These findings demonstrate that the increased α-ENaC subunit of pregnancy is associated with an mineralocorticoid-dependent increase in ENaC activity. Further, we show that ENaC activity is a major contributor of plasma volume status in late pregnancy. These changes are likely to contribute to the renal sodium retention and plasma volume expansion required for an optimal pregnancy.

  19. Lowering Plasma Glucose Concentration by Inhibiting Renal Sodium-Glucose Co-Transport

    Science.gov (United States)

    Abdul-Ghani, Muhammad A; DeFronzo, Ralph A

    2017-01-01

    Maintaining normoglycaemia not only reduces the risk of diabetic microvascular complications but also corrects the metabolic abnormalities that contribute to the development and progression of hyperglycaemia (i.e. insulin resistance and beta-cell dysfunction). Progressive beta-cell failure, in addition to the multiple side effects associated with many current antihyperglycaemic agents (e.g., hypoglycaemia and weight gain) presents major obstacle to the achievement of the recommended goal of glycaemic control in patients with diabetes mellitus (DM). Thus, novel effective therapies are needed for optimal glucose control in subjects with DM. Recently, specific inhibitors of renal sodium glucose cotransporter 2 (SGLT2) have been developed to produce glucosuria and lower the plasma glucose concentration. Because of their unique mechanism of action (which is independent of the secretion and action of insulin), these agents are effective in lowering the plasma glucose concentration in all stages of DM and can be combined with all other antidiabetic agents. In this review, we summarize the available data concerning the mechanism of action, efficacy and safety of this novel class of antidiabetic agent. PMID:24690096

  20. Renal sodium-glucose cotransporter inhibition in the management of type 2 diabetes mellitus

    Science.gov (United States)

    Abdul-Ghani, Muhammad A.; Norton, Luke

    2015-01-01

    Hyperglycemia is the primary factor responsible for the microvascular, and to a lesser extent macrovascular, complications of diabetes. Despite this well-established relationship, approximately half of all type 2 diabetic patients in the US have a hemoglobin A1c (HbA1c) ≥7.0%. This is associated in part with the side effects, i.e., weight gain and hypoglycemia, of currently available antidiabetic agents and in part with the failure to utilize medications that reverse the basic pathophysiological defects present in patients with type 2 diabetes. The kidney has been shown to play a central role in the development of hyperglycemia by excessive production of glucose throughout the sleeping hours and enhanced reabsorption of filtered glucose by the renal tubules secondary to an increase in the threshold at which glucose spills into the urine. Recently, a new class of antidiabetic agents, the sodium-glucose cotransporter 2 (SGLT2) inhibitors, has been developed and approved for the treatment of patients with type 2 diabetes. In this review, we examine their mechanism of action, efficacy, safety, and place in the therapeutic armamentarium. Since the SGLT2 inhibitors have a unique mode of action that differs from all other oral and injectable antidiabetic agents, they can be used at all stages of the disease and in combination with all other antidiabetic medications. PMID:26354881

  1. Renal hemodynamics in uranyl acetate-induced acute renal failure of rabbits

    International Nuclear Information System (INIS)

    Sudo, M.; Honda, N.; Hishida, A.; Nagase, M.

    1977-01-01

    The role of renal hemodynamic alterations in the curtailment of renal function was studied in rabbits with uranyl acetate-induced acute renal failure. The day following the i.v. injection of uranyl acetate (2 mg/kg of body wt), renal blood flow (RBF) and clearance of creatinine (Ccr) decreased to approximately 60 and 20% of controls, respectively. Intracortical fractional flow distribution, estimated by radioactive microsphere method, did not change. The extraction ratio of para-aminohippurate (EPAH) decreased and the renal extraction of sodium (CNa/Ccr) increased, with minimal structural change in the kidney. Urine output increased two to three times that of the control. After three days oliguria appeared despite complete recovery of RBF. The zonal flow redistributed toward the deep cortex. CCr and EPAH reached their minimums, concomitantly with tubular necrosis and intratubular casts. After seven days animals could be divided into the oliguric and diuretic groups. CCr and EPAH were higher in the diuretic group, while there was no significant difference in RBF and the flow distribution between groups. Regeneration of damaged tubular cells was found in the diuretic group but not in the oliguric group. The findings suggest the minor roles of RBF and the intracortical flow distribution, and a fundamental role of back leakage of filtrate across damaged tubular epithelium in the maintenance of reduced CCR and urine output during the oliguric stage in rabbits with uranyl acetate-induced renal failure

  2. Effect of sodium nitrite on renal function, sodium and water excretion and brachial and central blood pressure in healthy subjects. A dose-response study

    DEFF Research Database (Denmark)

    Rosenbaek, Jeppe Bakkestroem; Therwani, Safa Al; Jensen, Janni Majgaard

    2017-01-01

    Sodium nitrite (NaNO2) is converted to nitric oxide (NO) in vivo and has vasodilatory and natriuretic effects. Our aim was to examine the effects of NaNO2 on hemodynamics, sodium excretion and GFR. In a single-blinded, placebo-controlled, cross-over study, we infused placebo (0.9% NaCl) or 0.58, ....... The lack of increase in cGMP accompanying the increase in NO2(-), suggests a direct effect of nitrite or nitrate on the renal tubules and vascular bed with little or no systemic conversion to NO.......Sodium nitrite (NaNO2) is converted to nitric oxide (NO) in vivo and has vasodilatory and natriuretic effects. Our aim was to examine the effects of NaNO2 on hemodynamics, sodium excretion and GFR. In a single-blinded, placebo-controlled, cross-over study, we infused placebo (0.9% NaCl) or 0.58, 1.......74, or 3.48 μmol NaNO2/kg/hour for two hours in twelve healthy subjects, after four days standard diet. Subjects were supine and water-loaded. We measured brachial and central blood pressure (BP), plasma concentrations of renin, angiotensin II, aldosterone, arginine vasopressin (P-AVP), and plasma nitrite...

  3. Sodium

    Science.gov (United States)

    Table salt is a combination of two minerals - sodium and chloride Your body needs some sodium to work properly. It helps with the function ... in your body. Your kidneys control how much sodium is in your body. If you have too ...

  4. Effects of a long-acting formulation of octreotide on renal function and renal sodium handling in cirrhotic patients with portal hypertension: a randomized, double-blind, controlled trial

    DEFF Research Database (Denmark)

    Ottesen, L.H.; Aagaard, Niels Kristian; Kiszka-Kanowitz, M.

    2001-01-01

    variable effects. Twenty-five cirrhotic patients with portal hypertension were randomized in a double-blind design to placebo or a single subcutaneous dose of a long-acting formulation of octreotide (octreotide-LAR) (20 mg). Renal function tests were performed before dosing and repeated after 30 days...... with octreotide-LAR. It is concluded that in spite of increased arterial pressure, octreotide-LAR has no significant effect on renal hemodynamics and tubular function in clinically stable cirrhotic patients with portal hypertension....

  5. The Use of Fibrous, Supramolecular Membranes and Human Tubular Cells for Renal Epithelial Tissue Engineering : Towards a Suitable Membrane for a Bioartificial Kidney

    NARCIS (Netherlands)

    Dankers, Patricia Y. W.; Boomker, Jasper M.; Huizinga-van der Vlag, Ali; Smedts, Frank M. M.; Harmsen, Martin C.; van Luyn, Marja J. A.

    2010-01-01

    A bioartificial kidney, which is composed of a membrane cartridge with renal epithelial cells, can substitute important kidney functions in patients with renal failure. A particular challenge is the maintenance of monolayer integrity and specialized renal epithelial cell functions ex vivo. We

  6. The use of fibrous, supramolecular membranes and human tubular cells for renal epithelial tissue engineering: towards a suitable membrane for a bioartificial kidney,

    NARCIS (Netherlands)

    Dankers, P.Y.W.; Boomker, J.M.; Huizinga-van der Vlag, A.; Smedts, F.M.M.; Harmsen, M.C.; Luyn, van M.J.A.

    2010-01-01

    A bioartificial kidney, which is composed of a membrane cartridge with renal epithelial cells, can substitute important kidney functions in patients with renal failure. A particular challenge is the maintenance of monolayer integrity and specialized renal epithelial cell functions ex vivo. We

  7. The Synergistic Roles of Cholecystokinin B and Dopamine D5 Receptors on the Regulation of Renal Sodium Excretion.

    Directory of Open Access Journals (Sweden)

    Xiaoliang Jiang

    Full Text Available Renal dopamine D1-like receptors (D1R and D5R and the gastrin receptor (CCKBR are involved in the maintenance of sodium homeostasis. The D1R has been found to interact synergistically with CCKBR in renal proximal tubule (RPT cells to promote natriuresis and diuresis. D5R, which has a higher affinity for dopamine than D1R, has some constitutive activity. Hence, we sought to investigate the interaction between D5R and CCKBR in the regulation of renal sodium excretion. In present study, we found D5R and CCKBR increase each other's expression in a concentration- and time-dependent manner in the HK-2 cell, the specificity of which was verified in HEK293 cells heterologously expressing both human D5R and CCKBR and in RPT cells from a male normotensive human. The specificity of D5R in the D5R and CCKBR interaction was verified further using a selective D5R antagonist, LE-PM436. Also, D5R and CCKBR colocalize and co-immunoprecipitate in BALB/c mouse RPTs and human RPT cells. CCKBR protein expression in plasma membrane-enriched fractions of renal cortex (PMFs is greater in D5R-/- mice than D5R+/+ littermates and D5R protein expression in PMFs is also greater in CCKBR-/- mice than CCKBR+/+ littermates. High salt diet, relative to normal salt diet, increased the expression of CCKBR and D5R proteins in PMFs. Disruption of CCKBR in mice caused hypertension and decreased sodium excretion. The natriuresis in salt-loaded BALB/c mice was decreased by YF476, a CCKBR antagonist and Sch23390, a D1R/D5R antagonist. Furthermore, the natriuresis caused by gastrin was blocked by Sch23390 while the natriuresis caused by fenoldopam, a D1R/D5R agonist, was blocked by YF476. Taken together, our findings indicate that CCKBR and D5R synergistically interact in the kidney, which may contribute to the maintenance of normal sodium balance following an increase in sodium intake.

  8. Saline-induced natriuresis and renal blood flow in conscious dogs: effects of sodium infusion rate and concentration

    DEFF Research Database (Denmark)

    Sandgaard, N C F; Andersen, J L; Holstein-Rathlou, N-H

    2005-01-01

    AIM: This study focused on static and dynamic changes in total renal blood flow (RBF) during volume expansion and tested whether a change in RBF characteristics is a necessary effector mechanism in saline-induced natriuresis. METHODS: The aortic flow subtraction technique was used to measure RBF...... continuously. Identical amounts of NaCl (2.4 mmol kg(-1)) were given as slow isotonic (Iso, 120 min), slow hypertonic (Hyper, 120 min), and rapid isotonic loads (IsoRapid, 30 min). RESULTS: During Iso and IsoRapid, arterial blood pressure increased slightly (6-7 mmHg), and during Hyper it remained unchanged...... saline loading simulating daily sodium intake, the rate of sodium excretion may increase 10-20-fold without any change in mean arterial blood pressure or in RBF. Regulatory responses to changes in total body NaCl levels appears, therefore, to be mediated primarily by neurohumoral mechanisms and may occur...

  9. Radionuclide evaluation of renal transplants

    International Nuclear Information System (INIS)

    Yang Hong; Zhao Deshan

    2000-01-01

    Radionuclide renal imaging and plasma clearance methods can quickly quantitate renal blood flow and function in renal transplants. They can diagnose acute tubular necrosis and rejection, renal scar, surgical complications such as urine leaks, obstruction and renal artery stenosis after renal transplants. At the same time they can assess the therapy effect of renal transplant complications and can also predict renal transplant survival from early post-operative function studies

  10. A micropuncture study of proximal tubular transport of lithium during osmotic diuresis

    DEFF Research Database (Denmark)

    Leyssac, P P; Holstein-Rathlou, N H; Skøtt, P

    1990-01-01

    Lithium and sodium are normally reabsorbed in parallel with water by the renal proximal tubule whereby their tubular fluid-to-plasma concentration ratios (TF/P) remain close to unity throughout the proximal convoluted segment. During osmotic diuresis, the late proximal (TF/P)Na is known to decrease....... The present experiments were undertaken to study whether the late proximal TF/P for Li decreases like that of Na during osmotic diuresis. Data were obtained in a control period (C) and in two successive periods during mannitol diuresis (P1, P2). Glomerular filtration rate decreased gradually during osmotic...

  11. Telmisartan, a possible PPAR-δ agonist, reduces TNF-α-stimulated VEGF-C production by inhibiting the p38MAPK/HSP27 pathway in human proximal renal tubular cells

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Hideki, E-mail: hkimura@u-fukui.ac.jp [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan); Department of Clinical Laboratories and Nephrology, University of Fukui Hospital, Fukui (Japan); Mikami, Daisuke; Kamiyama, Kazuko [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan); Sugimoto, Hidehiro [Department of Clinical Laboratories and Nephrology, University of Fukui Hospital, Fukui (Japan); Kasuno, Kenji; Takahashi, Naoki [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan); Yoshida, Haruyoshi [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan); Division of Nephrology, Obama Municipal Hospital, Obama, Fukui (Japan); Iwano, Masayuki [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan)

    2014-11-14

    Highlights: • TNF-α increased VEGF-C expression by enhancing phosphorylation of p38MAPK and HSP27. • Telmisartan decreased TNF-α-stimulated expression of VEGF-C. • Telmisartan suppressed TNF-α-induced phosphorylation of p38MAPK and HSP27. • Telmisartan activated endogenous PPAR-δ protein. • Telmisartan suppressed p38MAPK phosphorylation in a PPAR-δ-dependent manner. - Abstract: Vascular endothelial growth factor-C (VEGF-C) is a main inducer of inflammation-associated lymphangiogenesis in various inflammatory disorders including chronic progressive kidney diseases, for which angiotensin II receptor type 1 blockers (ARBs) are widely used as the main treatment. Although proximal renal tubular cells may affect the formation of lymphatic vessels in the interstitial area by producing VEGF-C, the molecular mechanisms of VEGF-C production and its manipulation by ARB have not yet been examined in human proximal renal tubular epithelial cells (HPTECs). In the present study, TNF-α dose-dependently induced the production of VEGF-C in HPTECs. The TNF-α-induced production of VEGF-C was mediated by the phosphorylation of p38MAPK and HSP27, but not by that of ERK or NFkB. Telmisartan, an ARB that can activate the peroxisome proliferator-activated receptor (PPAR), served as a PPAR-δ activator and reduced the TNF-α-stimulated production of VEGF-C. This reduction was partially attributed to a PPAR-δ-dependent decrease in p38MAPK phosphorylation. Our results indicate that TNF-α induced the production of VEGF-C in HPTECs by activating p38MAPK/HSP27, and this was partially inhibited by telmisartan in a PPAR-δ dependent manner. These results provide a novel insight into inflammation-associated lymphangiogenesis.

  12. Downregulation of the S1P Transporter Spinster Homology Protein 2 (Spns2 Exerts an Anti-Fibrotic and Anti-Inflammatory Effect in Human Renal Proximal Tubular Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Olivier Blanchard

    2018-05-01

    Full Text Available Sphingosine kinase (SK catalyses the formation of sphingosine 1-phosphate (S1P, which acts as a key regulator of inflammatory and fibrotic reactions, mainly via S1P receptor activation. Here, we show that in the human renal proximal tubular epithelial cell line HK2, the profibrotic mediator transforming growth factor β (TGFβ induces SK-1 mRNA and protein expression, and in parallel, it also upregulates the expression of the fibrotic markers connective tissue growth factor (CTGF and fibronectin. Stable downregulation of SK-1 by RNAi resulted in the increased expression of CTGF, suggesting a suppressive effect of SK-1-derived intracellular S1P in the fibrotic process, which is lost when SK-1 is downregulated. In a further approach, the S1P transporter Spns2, which is known to export S1P and thereby reduces intracellular S1P levels, was stably downregulated in HK2 cells by RNAi. This treatment decreased TGFβ-induced CTGF and fibronectin expression, and it abolished the strong induction of the monocyte chemotactic protein 1 (MCP-1 by the pro-inflammatory cytokines tumor necrosis factor (TNFα and interleukin (IL-1β. Moreover, it enhanced the expression of aquaporin 1, which is an important water channel that is expressed in the proximal tubules, and reverted aquaporin 1 downregulation induced by IL-1β/TNFα. On the other hand, overexpression of a Spns2-GFP construct increased S1P secretion and it resulted in enhanced TGFβ-induced CTGF expression. In summary, our data demonstrate that in human renal proximal tubular epithelial cells, SK-1 downregulation accelerates an inflammatory and fibrotic reaction, whereas Spns2 downregulation has an opposite effect. We conclude that Spns2 represents a promising new target for the treatment of tubulointerstitial inflammation and fibrosis.

  13. Purinergic Signalling in Inflammatory Renal Disease

    Directory of Open Access Journals (Sweden)

    Nishkantha eArulkumaran

    2013-07-01

    Full Text Available Extracellular purines have a role in renal physiology and adaption to inflammation. However, inflammatory renal disease may be mediated by extracellular purines, resulting in renal injury. The role of purinergic signalling is dependent on the concentrations of extracellular purines. Low basal levels of purines are important in normal homeostasis and growth. Concentrations of extracellular purines are significantly elevated during inflammation and mediate either an adaptive role or propagate local inflammation. Adenosine signalling mediates alterations in regional renal blood flow by regulation of the renal microcirculation, tubulo-glomerular feedback, and tubular transport of sodium and water. Increased extracellular ATP and renal P2 receptor-mediated inflammation are associated with various renal diseases, including hypertension, diabetic nephropathy, and glomerulonephritis. Experimental data suggests P2 receptor deficiency or receptor antagonism is associated with amelioration of antibody-mediated nephritis, suggesting a pathogenic (rather than adaptive role of purinergic signalling. We discuss the role of extracellular nucleotides in adaptation to ischaemic renal injury and in the pathogenesis of inflammatory renal disease.

  14. Erythrocyte deformation in ischemic acute tubular necrosis and amelioration by splenectomy in the dog.

    Science.gov (United States)

    Mandal, A K; Taylor, C A; Bell, R D; Hillman, N M; Jarnot, M D; Cunningham, J D; Phillips, L G

    1991-11-01

    Bilateral renal artery occlusion (RAO) for 120 minutes in dogs results in acute tubular necrosis (ATN) and peritubular capillary (PTC) congestion with rapidly deteriorating renal function. We have shown that prior splenectomy minimizes RAO-induced renal functional and histopathologic changes. The purpose of this study was to examine whether this renal protection is due to prevention of red blood cell echinocyte formation and resultant renal PTC congestion. Echinocytes (burr cells) are poorly deformable, impart high viscosity to the blood, and may hinder reperfusion by increasing resistance to renal capillary blood flow. Splenectomized (SPLX) or sham-SPLX dogs were treated with bilateral RAO for 120 minutes. After RAO, renal function and renal blood flow were monitored, and peripheral blood red blood cells were examined at 1 hour and at 24-hour intervals for 96 hours. Renal biopsies were taken 1 hour after RAO and the kidneys removed 96 hours after RAO. The RBCs and renal tissues were studied using scanning electron microscopy. Renal function was assessed by endogenous creatinine clearance. Sham-SPLX animals showed a marked and sustained decrease in creatinine clearance, consistently elevated serum creatinine levels and fractional excretion of sodium, and diffuse ATN and PTC congestion with echinocytes. These animals had a peak in circulating echinocytes 1 hour after RAO (p less than 0.05), which showed an excellent negative correlation with creatinine clearance (r = -0.999; p less than 0.001). On the contrary, SPLX animals had essentially no change in serum creatinine or fractional excretion of sodium, minimal tubular changes, no PTC congestion, and no rise in circulating echinocytes during the 96-hour observation. In vitro treatment of the postischemic red blood cells from sham animals with adenosine-inosine or fresh postischemic plasma from the SPLX animals showed almost complete reversal to discocytes (normal red blood cells), whereas in vitro treatment of

  15. Drug-induced renal injury

    African Journals Online (AJOL)

    The kidney receives a rich blood flow of 25% of resting cardiac output ... Drugs can cause acute renal failure by causing pre-renal, intrinsic or .... tubular epithelial cells causing cell swelling ... the dose as required or prescribe alternative drugs.

  16. Renal aquaporins and sodium transporters with special focus on urinary tract obstruction

    DEFF Research Database (Denmark)

    Frøkiaer, Jørgen; Li, Chunling; Shi, Yimin

    2003-01-01

    seven aquaporins are expressed at distinct sites in the kidney and 4 members of this family (AQP1-4) have been demonstrated to play pivotal roles in the physiology and pathophysiology for renal regulation of body water balance. Osmotic equilibration via renal aquaporins is maintained by active transport......The discovery of aquaporin-1 (AQP1) by Agre and colleagues explained the long-standing biophysical question of how water specifically crosses biological membranes. These studies led to the discovery and identification of a whole new family of membrane proteins, the aquaporins. At present, at least...

  17. The Flavonoid Apigenin Ameliorates Cisplatin-Induced Nephrotoxicity through Reduction of p53 Activation and Promotion of PI3K/Akt Pathway in Human Renal Proximal Tubular Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Sung Min Ju

    2015-01-01

    Full Text Available Apigenin is a member of the flavone subclass of flavonoids present in fruits and vegetables. Apigenin has long been considered to have various biological activities, such as antioxidant, anti-inflammatory, and antitumorigenic properties, in various cell types. Cisplatin was known to exhibit cytotoxic effect to renal cells by inducing apoptosis through activation of p53. The present study investigated the antiapoptotic effects of apigenin on the cisplatin-treated human renal proximal tubular epithelial (HK-2 cells. HK-2 cells were pretreated with apigenin (5, 10, 20 μM for 1 h and then treated with 40 μM cisplatin for various times. Apigenin inhibited the cisplatin-induced apoptosis of HK-2 cells. Interestingly, apigenin itself exerted cytostatic activity because of its ability to induce cell cycle arrest. Apigenin inhibited caspase-3 activity and PARP cleavage in cisplatin-treated cells. Apigenin reduced cisplatin-induced phosphorylation and expression of p53, with no significant influence on production of ROS that is known to induce p53 activation. Furthermore, apigenin promoted cisplatin-induced Akt phosphorylation, suggesting that enhanced Akt activation may be involved in cytoprotection. Taken together, these results suggest that apigenin ameliorates cisplatin-induced apoptosis through reduction of p53 activation and promotion of PI3K/Akt pathway in HK-2 cells.

  18. Renal involvement in dogs with babesiosis

    Directory of Open Access Journals (Sweden)

    R.G. Lobetti

    2001-07-01

    Full Text Available Proteinuria, and renal tubular casts and epithelial cells in urine sediment, are commonly observed in both complicated and uncomplicated babesiosis, but do not necessarily reflect or predict renal failure. This study investigated the presence and degree of renal damage in canine babesiosis. Renal function and integrity were evaluated using serum urea and creatinine, serum electrolytes (sodium and potassium, fractional clearance of sodium (FcNa and potassium (FcK, urine enzyme activity of gamma-glutamyl transpeptidase and alkaline phosphatase, urine protein:creatinine ratio, and urinalysis. One control group (n =10 and 3 groups of babesiosis cases were studied: mild uncomplicated (n =10, severe uncomplicated (n = 11, and complicated (n = 9. All babesiosis groups showed well-concentrated urine. Mean serum urea was elevated in the severe and complicated groups, and was significantly different from the control group. There was no statistically significant difference between the groups for creatinine, although the complicated group had a mean value above the normal reference range. Hypokalaemia was uncommon in all the groups. Hyperkalaemia was present in only 2 dogs in the complicated group. Marginal hyponatraemia was present in a minority of dogs in all groups. The serumelectrolytes were not significantly different between groups. There was no overall elevation, nor any statistically significant difference in both the FcNa and FcK between the groups. Only 1 dog, in the complicated group, showed marked enzymuria. Proteinuria was a common finding and was significantly different between the severe and complicated groups and the control group. Some dogs in all groups had renal tubular epithelial cells in the urinary sediment, which increased in severity from the mild to the complicated groups and was significantly different from the control group. This study demonstrated that minimal renal damage occurs more often in canine babesiosis than significant

  19. sodium

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les initiatives de réduction de la consommation de sel qui visent l'ensemble de la population et qui ciblent la teneur en sodium des aliments et sensibilisent les consommateurs sont susceptibles de réduire la consommation de sel dans toutes les couches de la population et d'améliorer la santé cardiovasculaire. Ce projet a ...

  20. Grocery store baking soda. A source of sodium bicarbonate in the management of chronic metabolic acidosis.

    Science.gov (United States)

    Booth, B E; Gates, J; Morris, R C

    1984-02-01

    Oral sodium bicarbonate is used to treat metabolic acidosis in patients with renal tubular acidosis. Since infants and young children are unable to swallow tablets, those affected must ingest sodium bicarbonate in a powder or liquid form. Pharmacy-weighed sodium bicarbonate is expensive and inconvenient to obtain; some pharmacists are reluctant to provide it. We determined that the sodium bicarbonate contained in 8-oz boxes of Arm and Hammer Baking Soda was sufficiently constant in weight that, dissolved in water to a given volume, it yielded a quantitatively acceptable therapeutic solution of sodium bicarbonate at a cost of approximately 3 percent of that of pharmacy-weighed sodium bicarbonate. Grocery store baking soda can be a safe, economical, and convenient source of sodium bicarbonate for the treatment of chronic metabolic acidosis in infants and young children.

  1. Vascular Type 1A Angiotensin II Receptors Control BP by Regulating Renal Blood Flow and Urinary Sodium Excretion.

    Science.gov (United States)

    Sparks, Matthew A; Stegbauer, Johannes; Chen, Daian; Gomez, Jose A; Griffiths, Robert C; Azad, Hooman A; Herrera, Marcela; Gurley, Susan B; Coffman, Thomas M

    2015-12-01

    Inappropriate activation of the type 1A angiotensin (AT1A) receptor contributes to the pathogenesis of hypertension and its associated complications. To define the role for actions of vascular AT1A receptors in BP regulation and hypertension pathogenesis, we generated mice with cell-specific deletion of AT1A receptors in smooth muscle cells (SMKO mice) using Loxp technology and Cre transgenes with robust expression in both conductance and resistance arteries. We found that elimination of AT1A receptors from vascular smooth muscle cells (VSMCs) caused a modest (approximately 7 mmHg) yet significant reduction in baseline BP and exaggerated sodium sensitivity in mice. Additionally, the severity of angiotensin II (Ang II)-dependent hypertension was dramatically attenuated in SMKO mice, and this protection against hypertension was associated with enhanced urinary excretion of sodium. Despite the lower BP, acute vasoconstrictor responses to Ang II in the systemic vasculature were largely preserved (approximately 80% of control levels) in SMKO mice because of exaggerated activity of the sympathetic nervous system rather than residual actions of AT1B receptors. In contrast, Ang II-dependent responses in the renal circulation were almost completely eliminated in SMKO mice (approximately 5%-10% of control levels). These findings suggest that direct actions of AT1A receptors in VSMCs are essential for regulation of renal blood flow by Ang II and highlight the capacity of Ang II-dependent vascular responses in the kidney to effect natriuresis and BP control. Copyright © 2015 by the American Society of Nephrology.

  2. Thiazolidinediones enhance sodium-coupled bicarbonate absorption from renal proximal tubules via PPARγ-dependent nongenomic signaling.

    Science.gov (United States)

    Endo, Yoko; Suzuki, Masashi; Yamada, Hideomi; Horita, Shoko; Kunimi, Motoei; Yamazaki, Osamu; Shirai, Ayumi; Nakamura, Motonobu; Iso-O, Naoyuki; Li, Yuehong; Hara, Masumi; Tsukamoto, Kazuhisa; Moriyama, Nobuo; Kudo, Akihiko; Kawakami, Hayato; Yamauchi, Toshimasa; Kubota, Naoto; Kadowaki, Takashi; Kume, Haruki; Enomoto, Yutaka; Homma, Yukio; Seki, George; Fujita, Toshiro

    2011-05-04

    Thiazolidinediones (TZDs) improve insulin resistance by activating a nuclear hormone receptor, peroxisome proliferator-activated receptor γ (PPARγ). However, the use of TZDs is associated with plasma volume expansion through a mechanism that remains to be clarified. Here we showed that TZDs rapidly stimulate sodium-coupled bicarbonate absorption from the renal proximal tubule in vitro and in vivo. TZD-induced transport stimulation is dependent on PPARγ-Src-EGFR-ERK and observed in rat, rabbit and human, but not in mouse proximal tubules where Src-EGFR is constitutively activated. The existence of PPARγ-Src-dependent nongenomic signaling, which requires the ligand-binding ability, but not the transcriptional activity of PPARγ, is confirmed in mouse embryonic fibroblast cells. The enhancement of the association between PPARγ and Src by TZDs supports an indispensable role of Src in this signaling. These results suggest that the PPARγ-dependent nongenomic stimulation of renal proximal transport is also involved in TZD-induced volume expansion. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. The sodium-bicarbonate cotransporter NBCe2 (slc4a5) expressed in human renal proximal tubules shows increased apical expression under high-salt conditions.

    Science.gov (United States)

    Gildea, John J; Xu, Peng; Carlson, Julia M; Gaglione, Robert T; Bigler Wang, Dora; Kemp, Brandon A; Reyes, Camellia M; McGrath, Helen E; Carey, Robert M; Jose, Pedro A; Felder, Robin A

    2015-12-01

    The electrogenic sodium bicarbonate cotransporter (NBCe2) is encoded by SLC4A5, variants of which have been associated with salt sensitivity of blood pressure, which affects 25% of the adult population. NBCe2 is thought to mediate sodium bicarbonate cotransport primarily in the renal collecting duct, but NBCe2 mRNA is also found in the rodent renal proximal tubule (RPT). The protein expression or function of NBCe2 has not been demonstrated in the human RPT. We validated an NBCe2 antibody by shRNA and Western blot analysis, as well as overexpression of an epitope-tagged NBCe2 construct in both RPT cells (RPTCs) and human embryonic kidney 293 (HEK293) cells. Using this validated NBCe2 antibody, we found NBCe2 protein expression in the RPT of fresh and frozen human kidney slices, RPTCs isolated from human urine, and isolated RPTC apical membrane. Under basal conditions, NBCe2 was primarily found in the Golgi, while NBCe1 was primarily found at the basolateral membrane. Following an acute short-term increase in intracellular sodium, NBCe2 expression was increased at the apical membrane in cultured slices of human kidney and polarized, immortalized RPTCs. Sodium bicarbonate transport was increased by monensin and overexpression of NBCe2, decreased by NBCe2 shRNA, but not by NBCe1 shRNA, and blocked by 2,2'-(1,2-ethenediyl)bis[5-isothiocyanato-benzenesulfonic acid]. NBCe2 could be important in apical sodium and bicarbonate cotransport under high-salt conditions; the implication of the ex vivo studies to the in vivo situation when salt intake is increased remains unclear. Therefore, future studies will examine the role of NBCe2 in mediating increased renal sodium transport in humans whose blood pressures are elevated by an increase in sodium intake. Copyright © 2015 the American Physiological Society.

  4. Renal cysteine conjugate C-S lyase mediated toxicity of halogenated alkenes in primary cultures of human and rat proximal tubular cells.

    Science.gov (United States)

    McGoldrick, Trevor A; Lock, Edward A; Rodilla, Vicente; Hawksworth, Gabrielle M

    2003-07-01

    Proximal tubular cells from human (HPT) and rat (RPT) kidneys were isolated, grown to confluence and incubated with S-(1,2-dichlorovinyl)- l-cysteine (DCVC), S-(1,2,2-trichlorovinyl)- l-cysteine (TCVC), S-(1,1,2,2-tetrafluoroethyl)- l-cysteine (TFEC) and S-(2-chloro-1,1-difluorethyl)- l-cysteine (CDFEC), the cysteine conjugates of nephrotoxicants. The cultures were exposed to the conjugates for 12, 24 and 48 h and the toxicity determined using the MTT assay. All four conjugates caused dose-dependent toxicity to RPT cells over the range 50-1,000 microM, the order of toxicity being DCVC>TCVC>TFEC=CDFEC. The inclusion of aminooxyacetic acid (AOAA; 250 microM), an inhibitor of pyridoxal phosphate-dependent enzymes such as C-S lyase, afforded protection, indicating that C-S lyase has a role in the bioactivation of these conjugates. In HPT cultures only DCVC caused significant time- and dose-dependent toxicity. Exposure to DCVC (500 microM) for 48 h decreased cell viability to 7% of control cell values, whereas co-incubation of DCVC (500 microM) with AOAA (250 microM) resulted in cell viability of 71%. Human cultures were also exposed to S-(1,2-dichlorovinyl)-glutathione (DCVG). DCVG was toxic to HPT cells, but the onset of toxicity was delayed compared with the corresponding cysteine conjugate. AOAA afforded almost complete protection from DCVG toxicity. Acivicin (250 microM), an inhibitor of gamma-glutamyl transferase (gamma-GT), partially protected against DCVG (500 microM)-induced toxicity at 48 h (5% viability and 53% viability in the absence and presence of acivicin, respectively). These results suggest that DCVG requires processing by gamma-GT prior to bioactivation by C-S lyase in HPT cells. The activity of C-S lyase, using TFEC as a substrate, and glutamine transaminase K (GTK) was measured in rat and human cells with time in culture. C-S lyase activity in RPT and HPT cells decreased to approximately 30% of fresh cell values by the time the cells reached

  5. Role of renal sympathetic nerve activity in prenatal programming of hypertension.

    Science.gov (United States)

    Baum, Michel

    2018-03-01

    Prenatal insults, such as maternal dietary protein deprivation and uteroplacental insufficiency, lead to small for gestational age (SGA) neonates. Epidemiological studies from many different parts of the world have shown that SGA neonates are at increased risk for hypertension and early death from cardiovascular disease as adults. Animal models, including prenatal administration of dexamethasone, uterine artery ligation and maternal dietary protein restriction, result in SGA neonates with fewer nephrons than controls. These models are discussed in this educational review, which provides evidence that prenatal insults lead to altered sodium transport in multiple nephron segments. The factors that could result in increased sodium transport are discussed, focusing on new information that there is increased renal sympathetic nerve activity that may be responsible for augmented renal tubular sodium transport. Renal denervation abrogates the hypertension in programmed rats but has no effect on control rats. Other potential factors that could cause hypertension in programmed rats, such as the renin-angiotensin system, are also discussed.

  6. Activation of PI3K-Akt-GSK3β pathway mediates hepatocyte growth factor inhibition of RANTES expression in renal tubular epithelial cells

    International Nuclear Information System (INIS)

    Gong Rujun; Rifai, Abdalla; Dworkin, Lance D.

    2005-01-01

    Hepatocyte growth factor (HGF) was recently reported to ameliorate renal inflammation in a rat model of chronic renal failure. HGF exerted its action through suppression of RANTES expression in renal tubules. In the present study, we utilized an in vitro model of human kidney proximal tubule epithelial cells (HKC) to elucidate the mechanisms of RANTES suppression by HGF. HGF significantly suppressed basal and TNF-α-induced mRNA and protein expression of RANTES in a time and dose dependent fashion. HGF elicited PI3K-Akt activation and inhibited GSK3, a downstream transducer of PI3K-Akt, by inhibitory phosphorylation at Ser-9. When the PI3K-Akt pathway was blocked by wortmannin, HGF inhibition of RANTES was abrogated, demonstrating that the PI3K-Akt pathway is necessary for HGF action. In addition, specific inhibition of GSK3 activity by lithium ion suppressed basal and TNF-α-induced RANTES expression, reminiscent of the action of HGF. To further investigate the role of GSK3 in modulating RANTES expression, we examined the effect of forced expression of wild type GSK3β or an uninhibitable mutant GSK3β, in which the regulatory Ser-9 residue is changed to alanine (S9A-GSK3β) in HKC. Overexpression of wild type GSK3β did not alter the inhibitory action of HGF on RANTES. In contrast, expression of S9A-GSK3β abolished HGF inhibition of basal and TNF-α stimulated RANTES expression. These findings suggest that PI3K-Akt activation and subsequent inhibitory phosphorylation of GSK3β are required for HGF-induced suppression of RANTES in HKC

  7. Generation of Urinary Albumin Fragments Does Not Require Proximal Tubular Uptake

    OpenAIRE

    Weyer, K.; Nielsen, R.; Christensen, E. I.; Birn, H.

    2012-01-01

    Urinary albumin excretion is an important diagnostic and prognostic marker of renal function. Both animal and human urine contain large amounts of albumin fragments, but whether these fragments originate from renal tubular degradation of filtered albumin is unknown. Here, we used mice with kidneys lacking megalin and cubilin, the coreceptors that mediate proximal tubular endocytosis of albumin, to determine whether proximal tubular degradation of albumin forms the detectable urinary albumin f...

  8. Impact of renal aging on drug therapy.

    Science.gov (United States)

    Musso, Carlos G; Belloso, Waldo H; Scibona, Paula; Bellizzi, Vincenzo; Macías Núñez, Juan F

    2015-08-01

    Elderly patients (age ≥ 65 years old) use up to 30% of all commonly prescribed medication, and they suffer more their adverse effects than the general population. In order to minimize this risk, physicians should avoid polypharmacy, dangerous pharmacological interactions and take into account pharmacodynamic and senile pharmacokinetic changes before prescribing any medication to the elderly. The present review article originally describes how renal physiology changes secondary to aging such as dysautonomia, glomerular filtration rate reduction, tubular back-filtration, sodium, calcium and magnesium loss, potassium retention, altered dilution-concentration capability, tubular frailty, genetics, internal milieu and body composition are senile changes that when combined predispose elderly people to suffer from pharmacological adverse effects. Knowledge of these physiological modifications associated with aging and their impact on the pharmacology of particular drugs may help to optimize drug use and to avoid complications in this age group.

  9. Environmental exposure to cadmium at a level insufficient to induce renal tubular dysfunction does not affect bone density among female Japanese farmers

    International Nuclear Information System (INIS)

    Horiguchi, Hyogo; Oguma, Etsuko; Sasaki, Satoshi; Miyamoto, Kayoko; Ikeda, Yoko; Machida, Munehito; Kayama, Fujio

    2005-01-01

    Some recent research suggests that environmental exposure to cadmium, even at low levels, may increase the risk of osteoporosis, and that the bone demineralization is not just a secondary effect of renal dysfunction induced by high doses of cadmium as previously reported. To investigate the effect of exposure to cadmium at a level insufficient to induce kidney damage on bone mineral density (BMD) and bone metabolism, we conducted health examinations on 1380 female farmers from five districts in Japan who consumed rice contaminated by low-to-moderate levels of cadmium. We collected peripheral blood and urine samples and medical and nutritional information, and measured forearm BMD. Analysis of the data for subjects grouped by urinary cadmium level and age-related menstrual status suggested that cadmium accelerates both the increase of urinary calcium excretion around the time of menopause and the subsequent decrease in bone density after menopause. However, multivariate analyses showed no significant contribution of cadmium to bone density or urinary calcium excretion, indicating that the results mentioned above were confounded by other factors. These results indicate that environmental exposure to cadmium at levels insufficient to induce renal dysfunction does not increase the risk of osteoporosis, strongly supporting the established explanation for bone injury induced by cadmium as a secondary effect

  10. [Renal response to intravenous administration of sodium bicarbonate in newborn infants of different gestational ages].

    Science.gov (United States)

    Jasso-Gutiérrez, L; Araujo, B; Fuse-Moteji, R; del Castillo, E D

    1976-01-01

    The study comprised a series of 16 neonates made up of 5 patients of 33 weeks of gestation, 5 infants of 35 weeks and 6 more of 40 weeks of gestation. Blood pH, PaCO2 and HCO3- were measured together with bicarbonate, ammonium, titrable acidity and hydrogen ions in urine before and after intravenous infusion of sodium bicarbonate. Before infusion of bicarbonate, titrable acidity, ammonium and net acidity in urine were higher in accordance with a greater gestational age. As the administration of bicarbonate elapsed, titrable acidity, ammonium and net acidity dropped with increase in concentration of bicarbonate. A hypothesis is set forth that the differences found in the factors evaluated in urine before administration of bicarbonate depend on the physiologic characteristics set in the newborn by gestational age.

  11. Safety evaluation of a trial of lipocalin-directed sodium bicarbonate infusion for renal protection in at-risk critically ill patients.

    Science.gov (United States)

    Schneider, Antoine G; Bellomo, Rinaldo; Reade, Michael; Peck, Leah; Young, Helen; Eastwood, Glenn M; Garcia, Mercedes; Moore, Elizabeth; Harley, Nerina

    2013-06-01

    Urine alkalinisation with sodium bicarbonate decreases renal oxidative stress and might attenuate sepsisassociated acute kidney injury (s-AKI). The safety and feasibility of urine alkalinisation in patients at risk of s-AKI has never been tested. We randomly assigned patients at risk of s-AKI (those with systemic inflammatory response syndrome [SIRS], oliguria and elevated [≥150 µg/L] serum neutrophil gelatinase-associated lipocalin [sNGAL] concentration) to receive sodium bicarbonate (treatment group) or sodium chloride (placebo group) in a 0.5 mmol/kg bolus followed by an infusion of 0.2 mmol/kg/hour. Among 50 patients with SIRS and oliguria, 25 (50%) had an elevated sNGAL concentration. Of these, 13 were randomised to receive sodium bicarbonate and 12 to receive sodium chloride infusion. Study drugs were infused for a mean period of 25.9 hours (SD, 10 hours). Severe electrolyte abnormalities occurred in seven patients (28%) (four [30.8%] in the treatment group and three [25%] in the placebo group). These abnormalities resulted in early protocol cessation in six patients (24%) and study drug suspension in one patient (4%). This adverse event rate was judged to be unacceptable and the study was terminated early. There was no difference between the two groups in sNGAL or urinary NGAL concentrations over time, occurrence of acute kidney injury, requirement for renal replacement therapy, hospital length-of-stay or mortality. Administration of sodium bicarbonate and sodium chloride solutions to patients at risk of s-AKI was associated with frequent major electrolyte abnormalities and early protocol cessation. The tested protocol does not appear safe or feasible.

  12. Diminution of oxalate induced renal tubular epithelial cell injury and inhibition of calcium oxalate crystallization in vitro by aqueous extract of Tribulus terrestris

    Directory of Open Access Journals (Sweden)

    A. Aggarwal

    2010-08-01

    Full Text Available PURPOSE: Recurrence and persistent side effects of present day treatment for urolithiasis restrict their use, so an alternate solution, using phytotherapy is being sought. The present study attempted to evaluate the antilithiatic properties of Tribulus terrestris commonly called as “gokhru” which is often used in ayurveda to treat various urinary diseases including urolithiasis. MATERIALS AND METHODS: The activity of Tribulus terrestris was investigated on nucleation and the growth of the calcium oxalate (CaOx crystals as well as on oxalate induced cell injury of NRK 52E renal epithelial cells. RESULTS: Tribulus terrestris extract exhibited a concentration dependent inhibition of nucleation and the growth of CaOx crystals. When NRK-52E cells were injured by exposure to oxalate for 72 h, Tribulus terrestris extract prevented the injury in a dose-dependent manner. On treatment with the different concentrations of the plant, the cell viability increased and lactate dehydrogenase release decreased in a concentration dependent manner. CONCLUSION: The current data suggests that Tribulus terrestris extract not only has a potential to inhibit nucleation and the growth of the CaOx crystals but also has a cytoprotective role. Our results indicate that it could be a potential candidate for phytotherapy against urolithiasis.

  13. Diminution of oxalate induced renal tubular epithelial cell injury and inhibition of calcium oxalate crystallization in vitro by aqueous extract of Tribulus terrestris.

    Science.gov (United States)

    Aggarwal, A; Tandon, S; Singla, S K; Tandon, C

    2010-01-01

    Recurrence and persistent side effects of present day treatment for urolithiasis restrict their use, so an alternate solution, using phytotherapy is being sought. The present study attempted to evaluate the antilithiatic properties of Tribulus terrestris commonly called as "gokhru" which is often used in ayurveda to treat various urinary diseases including urolithiasis. The activity of Tribulus terrestris was investigated on nucleation and the growth of the calcium oxalate (CaOx) crystals as well as on oxalate induced cell injury of NRK 52E renal epithelial cells. Tribulus terrestris extract exhibited a concentration dependent inhibition of nucleation and the growth of CaOx crystals. When NRK-52E cells were injured by exposure to oxalate for 72 h, Tribulus terrestris extract prevented the injury in a dose-dependent manner. On treatment with the different concentrations of the plant, the cell viability increased and lactate dehydrogenase release decreased in a concentration dependent manner. The current data suggests that Tribulus terrestris extract not only has a potential to inhibit nucleation and the growth of the CaOx crystals but also has a cytoprotective role. Our results indicate that it could be a potential candidate for phytotherapy against urolithiasis.

  14. Response of copper deficient rats to inhibitors of renal sodium reabsorption

    Energy Technology Data Exchange (ETDEWEB)

    Noordewier, B.; Saari, J.T. (Northwestern College, Orange City, IA (United States) USDA/ARS, Grand Forks, ND (United States))

    1991-03-11

    This study examined the effects of furosemide (Furo), a Loop diuretic, and amiloride (Am), a potassium (K)-sparing diuretic, on the excretion of sodium (Na) and K in copper-adequate (CuAdeq) and copper-deficient (CuDef) rats. Weanling male Sprague Dawley rats were fed a CuDef or CuAdeq diet ad libitum and given deionized water to drink. After 5 weeks on the diets, rats were assigned to one of four treatment regimens: Furo, Am or Furo + Am. Rats were anesthetized and electrolyte excretion was measured in 2 {times} 15 min control periods followed by 3 {times} 15 min treatment periods. Furo increased Na excretion in a dose dependent manner in both the CuAdeq and the CuDef rats. The response of the CuAdeq rats was slightly greater than that of the CuDef rats in each of the 3 treatment groups in which Furo was given. K excretion following Furo increased to the same extent in the CuAdeq and CuDef rats. The natriuretic response to Am alone was slightly greater in the CuDef than the CuAdeq rats. The antikaliuretic response of the CuDef rats was similar to that of the CuAdeq rats whether Am was given alone or in combination with Furo. These data show that CuDef rats respond to Furo and Am in a manner which is similar to that of CuAdeq rats, this indicates that the sensitivity of the Na reabsorption mechanisms to inhibition by diuretics is not markedly affected by copper deficiency.

  15. Elevated N-terminal pro-brain natriuretic peptide levels predict an enhanced anti-hypertensive and anti-proteinuric benefit of dietary sodium restriction and diuretics, but not angiotensin receptor blockade, in proteinuric renal patients

    NARCIS (Netherlands)

    Slagman, Maartje C. J.; Waanders, Femke; Vogt, Liffert; Damman, Kevin; Hemmelder, Marc; Navis, Gerjan; Laverman, Gozewijn D.

    Background. Renin angiotensin aldosterone system (RAAS) blockade only partly reduces blood pressure, proteinuria and renal and cardiovascular risk in chronic kidney disease (CKD) but often requires sodium targeting [i.e. low sodium diet (LS) and/or diuretics] for optimal efficacy. However, both

  16. Elevated N-terminal pro-brain natriuretic peptide levels predict an enhanced anti-hypertensive and anti-proteinuric benefit of dietary sodium restriction and diuretics, but not angiotensin receptor blockade, in proteinuric renal patients

    NARCIS (Netherlands)

    Slagman, Maartje C. J.; Waanders, Femke; Vogt, Liffert; Damman, Kevin; Hemmelder, Marc; Navis, Gerjan; Laverman, Gozewijn D.

    2012-01-01

    Background. Renin angiotensin aldosterone system (RAAS) blockade only partly reduces blood pressure, proteinuria and renal and cardiovascular risk in chronic kidney disease (CKD) but often requires sodium targeting [i.e. low sodium diet (LS) and/or diuretics] for optimal efficacy. However, both

  17. Calcium oxalate crystals induces tight junction disruption in distal renal tubular epithelial cells by activating ROS/Akt/p38 MAPK signaling pathway.

    Science.gov (United States)

    Yu, Lei; Gan, Xiuguo; Liu, Xukun; An, Ruihua

    2017-11-01

    Tight junction plays important roles in regulating paracellular transports and maintaining cell polarity. Calcium oxalate monohydrate (COM) crystals, the major crystalline composition of kidney stones, have been demonstrated to be able to cause tight junction disruption to accelerate renal cell injury. However, the cellular signaling involved in COM crystal-induced tight junction disruption remains largely to be investigated. In the present study, we proved that COM crystals induced tight junction disruption by activating ROS/Akt/p38 MAPK pathway. Treating Madin-Darby canine kidney (MDCK) cells with COM crystals induced a substantial increasing of ROS generation and activation of Akt that triggered subsequential activation of ASK1 and p38 mitogen-activated protein kinase (MAPK). Western blot revealed a significantly decreased expression of ZO-1 and occludin, two important structural proteins of tight junction. Besides, redistribution and dissociation of ZO-1 were observed by COM crystals treatment. Inhibition of ROS by N-acetyl-l-cysteine (NAC) attenuated the activation of Akt, ASK1, p38 MAPK, and down-regulation of ZO-1 and occludin. The redistribution and dissociation of ZO-1 were also alleviated by NAC treatment. These results indicated that ROS were involved in the regulation of tight junction disruption induced by COM crystals. In addition, the down-regulation of ZO-1 and occludin, the phosphorylation of ASK1 and p38 MAPK were also attenuated by MK-2206, an inhibitor of Akt kinase, implying Akt was involved in the disruption of tight junction upstream of p38 MAPK. Thus, these results suggested that ROS-Akt-p38 MAPK signaling pathway was activated in COM crystal-induced disruption of tight junction in MDCK cells.

  18. Effect of mitochondrial potassium channel on the renal protection mediated by sodium thiosulfate against ethylene glycol induced nephrolithiasis in rat model

    Directory of Open Access Journals (Sweden)

    N. Baldev

    2015-12-01

    Full Text Available Purpose: Sodium thiosulfate (STS is clinically reported to be a promising drug in preventing nephrolithiasis. However, its mechanism of action remains unclear. In the present study, we investigated the role of mitochondrial KATP channel in the renal protection mediated by STS. Materials and Methods: Nephrolithiasis was induced in Wistar rats by administrating 0.4% ethylene glycol (EG along with 1% ammonium chloride for one week in drinking water followed by only 0.75% EG for two weeks. Treatment groups received STS, mitochondrial KATP channel opener and closer exclusively or in combination with STS for two weeks. Results: Animals treated with STS showed normal renal tissue architecture, supported by near normal serum creatinine, urea and ALP activity. Diazoxide (mitochondria KATP channel opening treatment to the animal also showed normal renal tissue histology and improved serum chemistry. However, an opposite result was shown by glibenclamide (mitochondria KATP channel closer treated rats. STS administered along with diazoxide negated the renal protection rendered by diazoxide alone, while it imparted protection to the glibenclamide treated rats, formulating a mitochondria modulated STS action. Conclusion: The present study confirmed that STS render renal protection not only through chelation and antioxidant effect but also by modulating the mitochondrial KATP channel for preventing urolithiasis.

  19. Acute renal failure with sodium-glucose-cotransporter-2 inhibitors: Analysis of the FDA adverse event report system database.

    Science.gov (United States)

    Perlman, A; Heyman, S N; Matok, I; Stokar, J; Muszkat, M; Szalat, A

    2017-12-01

    Sodium-glucose-cotransporter-2 (SGLT2) inhibitors have recently been approved for the treatment of type II diabetes mellitus (T2DM). It has been proposed that these agents could induce acute renal failure (ARF) under certain conditions. This study aimed to evaluate the association between SGLT2-inhibitors and ARF in the FDA adverse event report system (FAERS) database. We analyzed adverse event cases submitted to FAERS between January 2013 and September 2016. ARF cases were identified using a structured medical query. Medications were identified using both brand and generic names. During the period evaluated, 18,915 reports (out of a total of 3,832,015 registered in FAERS) involved the use of SGLT2-inhibitors. SGLT2-inhibitors were reportedly associated with ARF in 1224 of these cases (6.4%), and were defined as the "primary" or "secondary" cause of the adverse event in 96.8% of these cases. The proportion of reports with ARF among reports with SGLT2 inhibitor was almost three-fold higher compared to reports without these drugs (ROR 2.88, 95% CI 2.71-3.05, p SGLT2-inhibitors was significantly greater than the proportion of ARF among cases with T2DM without SGLT2-inhibitors (ROR 1.68, 95% CI 1.57-1.8, p SGLT2-inhibitors, canagliflozin was associated with a higher proportion of reports of renal failure (7.3%), compared to empagliflozin and dapagliflozin (4.7% and 4.8% respectively, p SGLT2-inhibitors are associated with an increase in the proportion of reports of ARF compared to other medications. SGLT2-inhibitor agents may differ from one another in their respective risk for ARF. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

  20. Nitro-oleic acid ameliorates oxygen and glucose deprivation/re-oxygenation triggered oxidative stress in renal tubular cells via activation of Nrf2 and suppression of NADPH oxidase.

    Science.gov (United States)

    Nie, Huibin; Xue, Xia; Liu, Gang; Guan, Guangju; Liu, Haiying; Sun, Lina; Zhao, Long; Wang, Xueling; Chen, Zhixin

    2016-01-01

    Nitroalkene derivative of oleic acid (OA-NO 2 ), due to its ability to mediate revisable Michael addition, has been demonstrated to have various biological properties and become a therapeutic agent in various diseases. Though its antioxidant properties have been reported in different models of acute kidney injury (AKI), the mechanism by which OA-NO 2 attenuates intracellular oxidative stress is not well investigated. Here, we elucidated the anti-oxidative mechanism of OA-NO 2 in an in vitro model of renal ischemia/reperfusion (I/R) injury. Human tubular epithelial cells were subjected to oxygen and glucose deprivation/re-oxygenation (OGD/R) injury. Pretreatment with OA-NO 2 (1.25 μM, 45 min) attenuated OGD/R triggered reactive oxygen species (ROS) generation and subsequent mitochondrial membrane potential disruption. This action was mediated via up-regulating endogenous antioxidant defense components including superoxide dismutase (SOD1), heme oxygenase 1 (HO-1), and γ-glutamyl cysteine ligase modulatory subunits (GCLM). Moreover, subcellular fractionation analyses demonstrated that OA-NO 2 promoted nuclear translocation of nuclear factor-E2- related factor-2 (Nrf2) and Nrf2 siRNA partially abrogated these protective effects. In addition, OA-NO 2 inhibited NADPH oxidase activation and NADPH oxidase 4 (NOX4), NADPH oxidase 2 (NOX2) and p22 phox up-regulation after OGD/R injury, which was not relevant to Nrf2. These results contribute to clarify that the mechanism of OA-NO 2 reno-protection involves both inhibition of NADPH oxidase activity and induction of SOD1, Nrf2-dependent HO-1, and GCLM.

  1. Histopathological changes of renal tissue following sodium fluoride administration in two consecutive generations of mice. Correlation with the urinary elimination of fluoride.

    Science.gov (United States)

    Dimcevici Poesina, Nicoleta; Bălălău, Cristian; Nimigean, Vanda Roxana; Nimigean, Victor; Ion, Ion; Baconi, Daniela; Bârcă, Maria; Băran Poesina, Violeta

    2014-01-01

    of mice. Histopathological observation of the kidney has revealed granular dystrophy of the renal tubules, necrosis of the endothelial cells and of the mesangial cells of renal glomerulus. The study indicates that different sodium fluoride treatments produce some pathological aspects of the kidneys and influence the urinary elimination of fluoride in two consecutive generations of mice. For the higher doses, the pathological changes of the kidney are more important, and the urinary elimination of fluoride is higher, especially for the allopathic doses.

  2. Mucin 4 Gene Silencing Reduces Oxidative Stress and Calcium Oxalate Crystal Formation in Renal Tubular Epithelial Cells Through the Extracellular Signal-Regulated Kinase Signaling Pathway in Nephrolithiasis Rat Model

    Directory of Open Access Journals (Sweden)

    Ling Sun

    2018-05-01

    Full Text Available Background/Aims: Nephrolithiasis plagues a great number of patients all over the world. Increasing evidence shows that the extracellular signal-regulated kinase (ERK signaling pathway and renal tubular epithelial cell (RTEC dysfunction and attrition are central to the pathogenesis of kidney diseases. Mucin 4 (MUC4 is reported as an activator of ERK signaling pathway in epithelial cells. In this study, using rat models of calcium oxalate (CaOx nephrolithiasis, the present study aims to define the roles of MUC4 and ERK signaling pathway as contributors to oxidative stress and CaOx crystal formation in RTEC. Methods: Data sets of nephrolithiasis were searched using GEO database and a heat flow map was drawn. Then MUC4 function was predicted. Wistar rats were prepared for the purpose of model establishment of ethylene glycol and ammonium chloride induced CaOx nephrolithiasis. In order to assess the detailed regulatory mechanism of MUC4 silencing on the ERK signaling pathway and RTEC, we used recombinant plasmid to downregulate MUC4 expression in Wistar rat-based models. Samples from rat urine, serum and kidney tissues were reviewed to identify oxalic acid and calcium contents, BUN, Cr, Ca2+ and P3+ levels, calcium crystal formation in renal tubules and MUC4 positive expression rate. Finally, RT-qPCR, Western blot analysis, and ELISA were employed to access oxidative stress state and CaOx crystal formation in RTEC. Results: Initially, MUC4 was found to have an influence on the process of nephrolithiasis. MUC4 was upregulated in the CaOx nephrolithiasis model rats. We proved that the silencing of MUC4 triggered the inactivation of ERK signaling pathway. Following the silencing of MUC4 or the inhibition of ERK signaling pathway, the oxalic acid and calcium contents in rat urine, BUN, Cr, Ca2+ and P3+ levels in rat serum, p-ERK1/2, MCP-1 and OPN expressions in RTEC and H2O2 and MDA levels in the cultured supernatant were downregulated, but the GSH

  3. TUBULAR DISORDERS WITH RICKETS-LIKE SYNDROME

    Directory of Open Access Journals (Sweden)

    N.N. Kartamysheva

    2011-01-01

    Full Text Available Often under the guise of «ordinary» Rickets are more severe kidney diseases, developing as a result of inherited or acquired, primary or secondary defects in the renal tubules. Incorrect diagnosis leads to an inadequate therapy, rapid progression of disease and renal failure. The article describes the main approaches to the diagnosis and treatment of disorders of tubular rachitis similar syndrome, presents a number of clinical cases in author's practice.Key words: tubulopathy, acidosis, electrolyte disorders, rickets, rickets-like syndrome, diagnostics, treatment, children.

  4. Mechanisms of hypertension in renal radiation

    International Nuclear Information System (INIS)

    Juncos, L.; Cornejo, J.C.; Cejas, H.; Broglia, C.

    1990-01-01

    This study was undertaken to investigate the role played by renal functional and structural changes in the development of radiation-induced hypertension. Four groups of rats were studied: (1) left kidney radiated, (2) sham procedure, (3) uninephrectomy followed 3 weeks later by radiation of the contralateral kidney, and (4) uninephrectomy followed by sham procedure 3 weeks later. All radiated rats became hypertensive at 12 weeks (p less than 0.05) and had higher protein excretion (p less than 0.05). In the presence of an intact contralateral kidney, radiation causes mild-to-moderate histological abnormalities, and therefore, creatinine clearance and water and sodium handling do not change. Plasma renin activity increased in this group (p less than 0.05). Radiated uninephrectomized rats showed decreased creatinine clearance (p less than 0.05), but renin activity remained unchanged. These rats developed severe histological abnormalities in glomeruli, interstitia, tubuli, and vessels resulting in increased sodium and water output. The average of individual tubular and interstitial scores correlated significantly with both water intake and output but not with sodium excretion. These studies suggest that in the presence of an intact kidney, renin is an important determinant in the development or maintenance of radiation hypertension, whereas in the absence of the contralateral kidney, severe histological changes and renal failure are prominent despite increased water intake and output. The more severe glomerular sclerosis and proteinuria in the latter model could be related to diminished renal mass

  5. The crosstalk between the kidney and the central nervous system: the role of renal nerves in blood pressure regulation.

    Science.gov (United States)

    Nishi, Erika E; Bergamaschi, Cássia T; Campos, Ruy R

    2015-04-20

    What is the topic of this review? This review describes the role of renal nerves as the key carrier of signals from the kidneys to the CNS and vice versa; the brain and kidneys communicate through this carrier to maintain homeostasis in the body. What advances does it highlight? Whether renal or autonomic dysfunction is the predominant contributor to systemic hypertension is still debated. In this review, we focus on the role of the renal nerves in a model of renovascular hypertension. The sympathetic nervous system influences the renal regulation of arterial pressure and body fluid composition. Anatomical and physiological evidence has shown that sympathetic nerves mediate changes in urinary sodium and water excretion by regulating the renal tubular water and sodium reabsorption throughout the nephron, changes in the renal blood flow and the glomerular filtration rate by regulating the constriction of renal vasculature, and changes in the activity of the renin-angiotensin system by regulating the renin release from juxtaglomerular cells. Additionally, renal sensory afferent fibres project to the autonomic central nuclei that regulate blood pressure. Hence, renal nerves play a key role in the crosstalk between the kidneys and the CNS to maintain homeostasis in the body. Therefore, the increased sympathetic nerve activity to the kidney and the renal afferent nerve activity to the CNS may contribute to the outcome of diseases, such as hypertension. © 2014 The Authors. Experimental Physiology © 2014 The Physiological Society.

  6. Effect of perioperative sodium bicarbonate administration on renal function following cardiac surgery for infective endocarditis: a randomized, placebo-controlled trial.

    Science.gov (United States)

    Cho, Jin Sun; Soh, Sarah; Shim, Jae-Kwang; Kang, Sanghwa; Choi, Haegi; Kwak, Young-Lan

    2017-01-05

    Patients with infective endocarditis (IE) have an elevated risk of renal dysfunction because of extensive systemic inflammation and use of nephrotoxic antibiotics. In this randomized, placebo-controlled trial, we investigated whether perioperative sodium bicarbonate administration could attenuate postoperative renal dysfunction in patients with IE undergoing cardiac surgery. Seventy patients randomly received sodium chloride (n = 35) or sodium bicarbonate (n = 35). Sodium bicarbonate was administered as a 0.5 mmol/kg loading dose for 1 h commencing with anesthetic induction, followed by a 0.15 mmol/kg/h infusion for 23 h. The primary outcome was peak serum creatinine (SCr) level during the first 48 h postoperatively. The incidence of acute kidney injury, SCr level, estimated glomerular filtration rate, and major morbidity endpoints were assessed postoperatively. The peak SCr during the first 48 h postoperatively (bicarbonate vs. 1.01 (0.74, 1.37) mg/dl vs. 0.88 (0.76, 1.27) mg/dl, P = 0.474) and the incidence of acute kidney injury (bicarbonate vs. 29% vs. 23%, P = 0.584) were similar in both groups. The postoperative increase in SCr above baseline was greater in the bicarbonate group than in the control group on postoperative day 2 (0.21 (0.07, 0.33) mg/dl vs. 0.06 (0.00, 0.23) mg/dl, P = 0.028) and postoperative day 5 (0.23 (0.08, 0.36) mg/dl vs. 0.06 (0.00, 0.23) mg/dl, P = 0.017). Perioperative sodium bicarbonate administration had no favorable impact on postoperative renal function and outcomes in patients with IE undergoing cardiac surgery. Instead, it was associated with possibly harmful renal effects, illustrated by a greater increase in SCr postoperatively, compared to control. ClinicalTrials.gov, NCT01920126 . Registered on 31 July 2013.

  7. Effect of Sodium-Glucose Co-Transporter 2 Inhibitor, Dapagliflozin, on Renal Renin-Angiotensin System in an Animal Model of Type 2 Diabetes.

    Science.gov (United States)

    Shin, Seok Joon; Chung, Sungjin; Kim, Soo Jung; Lee, Eun-Mi; Yoo, Young-Hye; Kim, Ji-Won; Ahn, Yu-Bae; Kim, Eun-Sook; Moon, Sung-Dae; Kim, Myung-Jun; Ko, Seung-Hyun

    2016-01-01

    Renal renin-angiotensin system (RAS) activation is one of the important pathogenic mechanisms in the development of diabetic nephropathy in type 2 diabetes. The aim of this study was to investigate the effects of a sodium-glucose co-transporter 2 (SGLT-2) inhibitor, dapagliflozin, on renal RAS in an animal model with type 2 diabetes. Dapagliflozin (1.0 mg/kg, OL-DA) or voglibose (0.6 mg/kg, OL-VO, diabetic control) (n = 10 each) was administered to Otsuka Long-Evans Tokushima Fatty (OLETF) rats for 12 weeks. We used voglibose, an alpha-glucosidase inhibitor, as a comparable counterpart to SGLT2 inhibitor because of its postprandial glucose-lowering effect without proven renoprotective effects. Control Long-Evans Tokushima Otsuka (LT) and OLETF (OL-C) rats received saline (n = 10, each). Changes in blood glucose, urine albumin, creatinine clearance, and oxidative stress were measured. Inflammatory cell infiltration, mesangial widening, and interstitial fibrosis in the kidney were evaluated by histological analysis. The effects of dapagliflozin on renal expression of the RAS components were evaluated by quantitative RT-PCR in renal tissue. After treatment, hyperglycemia and urine microalbumin levels were attenuated in both OL-DA and OL-VO rather than in the OL-C group (P renal RAS component expression, oxidative stress and interstitial fibrosis in OLETF rats. We suggest that, in addition to control of hyperglycemia, partial suppression of renal RAS with an SGLT2 inhibitor would be a promising strategy for the prevention of treatment of diabetic nephropathy.

  8. INSUFICIENCIA RENAL AGUDA POR CISPLATINO: REPORTE DE UN CASO

    Directory of Open Access Journals (Sweden)

    Rodriguez Macías EL

    2016-01-01

    Full Text Available Cisplatin nephrotoxicity should always be considered as a potential cause of renal damage in acute renal failure installed in the context of its use. Among its mechanisms of renal functional impairment are: acute tubular necrosis, proximal tubular and loop of Henle dysfunctions, as well as the deterioration of various organelles, especially the mitochondria.

  9. Reliability of Tubular Joints

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    In this paper the preliminary results obtained by tests on tubular joints are presented. The joints are T-joints and the loading is static. It is the intention in continuation of these tests to perform tests on other types of joints (e.g. Y-joints) and also with dynamic loading. The purpose...... of the test is partly to obtain empirical data for the ultimate load-carrying capacity of tubular T-joints and partly to obtain some experience in performing tests with tubular joints. It is well known that tubular joints are usually designed in offshore engineering on the basis of empirical formulas obtained...... by experimental test results. Therefore, there is a need for performing experimental tests in this area....

  10. Sodium Bicarbonate Therapy in Patients with Metabolic Acidosis

    Science.gov (United States)

    Adeva-Andany, María M.; Fernández-Fernández, Carlos; Mouriño-Bayolo, David; Castro-Quintela, Elvira; Domínguez-Montero, Alberto

    2014-01-01

    Metabolic acidosis occurs when a relative accumulation of plasma anions in excess of cations reduces plasma pH. Replacement of sodium bicarbonate to patients with sodium bicarbonate loss due to diarrhea or renal proximal tubular acidosis is useful, but there is no definite evidence that sodium bicarbonate administration to patients with acute metabolic acidosis, including diabetic ketoacidosis, lactic acidosis, septic shock, intraoperative metabolic acidosis, or cardiac arrest, is beneficial regarding clinical outcomes or mortality rate. Patients with advanced chronic kidney disease usually show metabolic acidosis due to increased unmeasured anions and hyperchloremia. It has been suggested that metabolic acidosis might have a negative impact on progression of kidney dysfunction and that sodium bicarbonate administration might attenuate this effect, but further evaluation is required to validate such a renoprotective strategy. Sodium bicarbonate is the predominant buffer used in dialysis fluids and patients on maintenance dialysis are subjected to a load of sodium bicarbonate during the sessions, suffering a transient metabolic alkalosis of variable severity. Side effects associated with sodium bicarbonate therapy include hypercapnia, hypokalemia, ionized hypocalcemia, and QTc interval prolongation. The potential impact of regular sodium bicarbonate therapy on worsening vascular calcifications in patients with chronic kidney disease has been insufficiently investigated. PMID:25405229

  11. Sodium Bicarbonate Therapy in Patients with Metabolic Acidosis

    Directory of Open Access Journals (Sweden)

    María M. Adeva-Andany

    2014-01-01

    Full Text Available Metabolic acidosis occurs when a relative accumulation of plasma anions in excess of cations reduces plasma pH. Replacement of sodium bicarbonate to patients with sodium bicarbonate loss due to diarrhea or renal proximal tubular acidosis is useful, but there is no definite evidence that sodium bicarbonate administration to patients with acute metabolic acidosis, including diabetic ketoacidosis, lactic acidosis, septic shock, intraoperative metabolic acidosis, or cardiac arrest, is beneficial regarding clinical outcomes or mortality rate. Patients with advanced chronic kidney disease usually show metabolic acidosis due to increased unmeasured anions and hyperchloremia. It has been suggested that metabolic acidosis might have a negative impact on progression of kidney dysfunction and that sodium bicarbonate administration might attenuate this effect, but further evaluation is required to validate such a renoprotective strategy. Sodium bicarbonate is the predominant buffer used in dialysis fluids and patients on maintenance dialysis are subjected to a load of sodium bicarbonate during the sessions, suffering a transient metabolic alkalosis of variable severity. Side effects associated with sodium bicarbonate therapy include hypercapnia, hypokalemia, ionized hypocalcemia, and QTc interval prolongation. The potential impact of regular sodium bicarbonate therapy on worsening vascular calcifications in patients with chronic kidney disease has been insufficiently investigated.

  12. Radiological evaluation of renal transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Dorph, S [Herlev University Hospital, Copenhagen (Denmark). Dept. of Radiology

    1996-12-31

    Briefly discussed the nephrologic complications, episodes of rejection, acute tubular necrosis, cyclosporine, urologic complications, perirenal fluid collections, small asymptomatic hematomas, urinomas, abscesses, lymphocele, ureteral obstruction, cascular complications, imaging of the renal allograft, radionuclide imaging, ultrasonography, conventional radiography, cystograhy (8 refs.).

  13. Radiological evaluation of renal transplantation

    International Nuclear Information System (INIS)

    Dorph, S.

    1995-01-01

    Briefly discussed the nephrologic complications, episodes of rejection, acute tubular necrosis, cyclosporine, urologic complications, perirenal fluid collections, small asymptomatic hematomas, urinomas, abscesses, lymphocele, ureteral obstruction, cascular complications, imaging of the renal allograft, radionuclide imaging, ultrasonography, conventional radiography, cystograhy (8 refs.)

  14. Sodium lactate improves renal microvascular thrombosis compared to sodium bicarbonate and 0.9% NaCl in a porcine model of endotoxic shock: an experimental randomized open label controlled study.

    Science.gov (United States)

    Duburcq, Thibault; Durand, Arthur; Tournoys, Antoine; Gnemmi, Viviane; Gmyr, Valery; Pattou, François; Jourdain, Mercedes; Tamion, Fabienne; Besnier, Emmanuel; Préau, Sebastien; Parmentier-Decrucq, Erika; Mathieu, Daniel; Poissy, Julien; Favory, Raphaël

    2018-02-14

    Sodium lactate seemed to improve fluid balance and avoid fluid overload. The objective of this study was to determine if these beneficial effects can be at least partly explained by an improvement in disseminated intravascular coagulation (DIC)-associated renal microvascular thrombosis. Ancillary work of an interventional randomized open label controlled experimental study. Fifteen female "Large White" pigs (2 months old) were challenged with intravenous infusion of E. coli endotoxin. Three groups of five animals were randomly assigned to receive different fluids: a treatment group received sodium lactate 11.2% (SL group); an isotonic control group received 0.9% NaCl (NC group); a hypertonic control group, with the same amount of osmoles and sodium than SL group, received sodium bicarbonate 8.4% (SB group). Glomerular filtration rate (GFR) markers, coagulation and inflammation parameters were measured over a 5-h period. Immediately after euthanasia, kidneys were withdrawn for histological study. Statistical analysis was performed with nonparametric tests and the Dunn correction for multiple comparisons. A p < 0.05 was considered significant. The direct immunofluorescence study revealed that the percentage of capillary sections thrombosed in glomerulus were significantly lesser in SL group [5 (0-28) %] compared to NC [64 (43-79) %, p = 0.01] and SB [64 (43-79), p = 0.03] groups. Alterations in platelet count and fibrinogen level occurred earlier and were significantly more pronounced in both control groups compared to SL group (p < 0.05 at 210 and 300 min). The increase in thrombin-antithrombin complexes was significantly higher in NC [754 (367-945) μg/mL; p = 0.03] and SB [463 (249-592) μg/mL; p = 0.03] groups than in SL group [176 (37-265) μg/mL]. At the end of the experiment, creatinine clearance was significantly higher in SL group [55.46 (30.07-67.85) mL/min] compared to NC group [1.52 (0.17-27.67) mL/min, p = 0.03]. In this study, we

  15. Sodium butyrate suppresses angiotensin II-induced hypertension by inhibition of renal (pro)renin receptor and intrarenal renin-angiotensin system.

    Science.gov (United States)

    Wang, Lei; Zhu, Qing; Lu, Aihua; Liu, Xiaofen; Zhang, Linlin; Xu, Chuanming; Liu, Xiyang; Li, Haobo; Yang, Tianxin

    2017-09-01

    Butyrate, a short-chain fatty acid, is the end product of the fermentation of complex carbohydrates by the gut microbiota. Recently, sodium butyrate (NaBu) has been found to play a protective role in a number of chronic diseases. However, it is still unclear whether NaBu has a therapeutic potential in hypertension. The present study was aimed to investigate the role of NaBu in angiotensin II (Ang II)-induced hypertension and to further explore the underlying mechanism. Ang II was infused into uninephrectomized Sprague-Dawley rats with or without intramedullary infusion of NaBu for 14 days. Mean arterial blood pressure was recorded by the telemetry system. Renal tissues, serum samples, and 24-h urine samples were collected to examine renal injury and the regulation of the (pro)renin receptor (PRR) and renin. Intramedullary infusion of NaBu in Sprague-Dawley rats lowered the Ang II-induced mean arterial pressure from 129 ± 6 mmHg to 108 ± 4 mmHg (P renal injury, including urinary albumin, glomerulosclerosis, and renal fibrosis, as well as the expression of inflammatory mediators tumor necrosis factor α, interleukin 6. The renal expression of PRR, angiotensinogen, angiotensin I-converting enzyme and the urinary excretion of soluble PRR, renin, and angiotensinogen were all increased by Ang II infusion but decreased by NaBu treatment. In cultured innermedullary collecting duct cells, NaBu treatment attenuated Ang II-induced expression of PRR and renin. These results demonstrate that NaBu exerts an antihypertensive action, likely by suppressing the PRR-mediated intrarenal renin-angiotensin system.

  16. Genetics Home Reference: renal tubular dysgenesis

    Science.gov (United States)

    ... next step, angiotensin-converting enzyme (produced from the ACE gene) converts angiotensin I to angiotensin II. Angiotensin II ... proximal tubules) and other tissues. Mutations in the ACE , AGT , AGTR1 , or REN gene impair the production or function of angiotensin II, ...

  17. Central Diabetes Insipidus, Central Hypothyroidism, Renal Tubular ...

    African Journals Online (AJOL)

    readmitted to the hospital because of jaundice and failure to thrive, for which he was investigated and diagnosed to have central congenital hypothyroidism. Shortly thereafter, he was admitted to our institute with a history of vomiting, decreased oral intake, polyuria, and dehydration having lasted 5 days. He was investigated ...

  18. Renal excretion of prostaglandin metabolites, arginine vasopressin, and sodium during endotoxin and endogenous pyrogen induced fever in the goat.

    Science.gov (United States)

    Jónasson, H; Basu, S; Andersson, B; Kindahl, H

    1984-04-01

    Responses to intravenous injections of an endotoxin (E. coli-lipopolysaccharide, 1 microgram/kg b.wt.) and endogenous pyrogen were studied in euhydrated and hyperhydrated goats. The biphasic febrile response to the endotoxin was associated with a pronounced increase in the renal excretion of measured prostaglandin (PG) metabolites (11-ketotetranor PGF metabolites). This increase was time-correlated with the elevation of the rectal temperature, and (in hyperhydrated animals) with an inhibition of the water diuresis and an increase in renal excretion of arginine vasopressin (AVP). Other effects of the endotoxin were an immediate depression of renal Na and K excretion followed by the development of pronounced natriuresis, and a reduction of plasma Fe and Zn concentrations. The appearance of the febrile reactions (peripheral vasoconstriction and shivering) was accompanied by miosis. The maximum elevation of the rectal temperature was significantly greater during euhydration than during hyperhydration. Also endogenous pyrogen elicited miosis concomitant with febrile reactions, and an elevation of the renal excretion of PG metabolites which was closely correlated in time with the monophasic febrile response, and (during hyperhydration) with temporary inhibition of the water diuresis and an increase in the renal AVP excretion. However, the responses were much weaker than the corresponding endotoxin effects. No appreciable changes in renal excretion of Na and K were observed in response to the endogenous pyrogen. It is concluded that the observed effects on renal cation excretion were manifestations of direct endotoxin influences on kidney function.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Study of the permeability of the various parts of the tubules to sodium and potassium ions

    International Nuclear Information System (INIS)

    Morel, F.; Falbriard, A.

    1959-01-01

    The method of stop flow analysis has been used in rabbits together with radioactive sodium and potassium injected in the middle of a six minutes period of arrest of urine flow during an osmotic diuresis. Urine was subsequently collected in 60 ta 80 mg samples. The specific activities of sodium and potassium suggest that both ions pass directly from the renal interstitial tissue into the urine at different and distinct areas in the tubules. The whole distal segment, including the area of active reabsorption of this ion, is impermeable to sodium in the direction interstitial tissue to lumen. The adjacent, more proximal tubule is, however, extremely permeable. The distal tubular impermeability to potassium is more limited. The specific activity already having reached a maximum at the level of active sodium reabsorption. Reprint of a paper published in 'Revue Francaise d'Etudes Cliniques et Biologiques', n. 5, vol IV, p. 471-474 [fr

  20. Chemical chaperon 4-phenylbutyrate protects against the endoplasmic reticulum stress-mediated renal fibrosis in vivo and in vitro.

    Science.gov (United States)

    Liu, Shing-Hwa; Yang, Ching-Chin; Chan, Ding-Cheng; Wu, Cheng-Tien; Chen, Li-Ping; Huang, Jenq-Wen; Hung, Kuan-Yu; Chiang, Chih-Kang

    2016-04-19

    Renal tubulointerstitial fibrosis is the common and final pathologic change of kidney in end-stage renal disease. Interesting, endoplasmic reticulum (ER) stress is known to contribute to the pathophysiological mechanisms during the development of renal fibrosis. Here, we investigated the effects of chemical chaperon sodium 4-phenylbutyrate (4-PBA) on renal fibrosis in vivo and in vitro. In a rat unilateral ureteral obstruction (UUO) model, 4-PBA mimicked endogenous ER chaperon in the kidneys and significantly reduced glucose regulated protein 78 (GRP78), CCAAT/enhancer binding protein (C/EBP) homologous protein (CHOP), activating transcription factor 4 (ATF4), and phosphorylated JNK protein expressions as well as restored spliced X-box-binding protein 1 (XBP1) expressions in the kidneys of UUO rats. 4-PBA also attenuated the increases of α-smooth muscle actin (α-SMA), connective tissue growth factor (CTGF) protein expressions, tubulointerstitial fibrosis, and apoptosis in the kidneys of UUO rats. Moreover, transforming growth factor (TGF)-β markedly increased ER stress-associated molecules, profibrotic factors, and apoptotic markers in the renal tubular cells (NRK-52E), all of which could be significantly counteracted by 4-PBA treatment. 4-PBA also diminished TGF-β-increased CTGF promoter activity and CTGF mRNA expression in NRK-52E cells. Taken together, our results indicated that 4-PBA acts as an ER chaperone to ameliorate ER stress-induced renal tubular cell apoptosis and renal fibrosis.

  1. Recombinant erythropoietin acutely decreases renal perfusion and decouples the renin-angiotensin-aldosterone system.

    Science.gov (United States)

    Aachmann-Andersen, Niels J; Christensen, Soren J; Lisbjerg, Kristian; Oturai, Peter; Johansson, Pär I; Holstein-Rathlou, Niels-Henrik; Olsen, Niels V

    2018-03-01

    The effect of recombinant erythropoietin (rhEPO) on renal and systemic hemodynamics was evaluated in a randomized double-blinded, cross-over study. Sixteen healthy subjects were tested with placebo, or low-dose rhEPO for 2 weeks, or high-dose rhEPO for 3 days. Subjects refrained from excessive salt intake, according to instructions from a dietitian. Renal clearance studies were done for measurements of renal plasma flow, glomerular filtration rate (GFR) and the segmentel tubular handling of sodium and water (lithium clearance). rhEPO increased arterial blood pressure, total peripheral resistance, and renal vascular resistance, and decreased renal plasma flow in the high-dose rhEPO intervention and tended to decrease GFR. In spite of the decrease in renal perfusion, rhEPO tended to decrease reabsorption of sodium and water in the proximal tubule and induced a prompt decrease in circulating levels of renin and aldosterone, independent of changes in red blood cell mass, blood volumes, and blood pressure. We also found changes in biomarkers showing evidence that rhEPO induced a prothrombotic state. Our results suggest that rhEPO causes a direct downregulation in proximal tubular reabsorption that seems to decouple the activity of the renin-angiotensin-aldosterone system from changes in renal hemodynamics. This may serve as a negative feed-back mechanism on endogenous synthesis of EPO when circulating levels of EPO are high. These results demonstrates for the first time in humans a direct effect of rhEPO on renal hemodynamics and a decoupling of the renin-angiotensin-aldosterone system. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  2. Expression of renin-angiotensin system signalling compounds in maternal protein-restricted rats: effect on renal sodium excretion and blood pressure.

    Science.gov (United States)

    Mesquita, Flávia Fernandes; Gontijo, José Antonio Rocha; Boer, Patrícia Aline

    2010-02-01

    Intrauterine growth restriction due to low maternal dietary protein during pregnancy is associated with retardation of foetal growth, renal alterations and adult hypertension. The renin-angiotensin system (RAS) is a coordinated hormonal cascade in the control of cardiovascular, renal and adrenal function that governs body fluid and electrolyte balance, as well as arterial pressure. In the kidney, all the components of the renin-angiotensin system including angiotensin II type 1 (AT1) and type 2 (AT2) receptors are expressed locally during nephrogenesis. Hence, we investigated whether low protein diet intake during pregnancy altered kidney and adrenal expression of AT1(R) and AT2(R) receptors, their pathways and if the modified expression of the RAS compounds occurs associated with changes in urinary sodium and in arterial blood pressure in sixteen-week-old males' offspring of the underfed group. The pregnancy dams were divided in two groups: with normal protein diet (pups named NP) (17% protein) or low protein diet (pups LP) (6% protein) during all pregnancy. The present data confirm a significant enhancement in arterial pressure in the LP group. Furthermore, the study showed a significantly decreased expression of RAS pathway protein and Ang II receptors in the kidney and an increased expression in the adrenal of LP rats. The detailed immunohistochemical analysis of RAS signalling proteins in the kidney confirm the immunoblotting results for both groups. The present investigation also showed a pronounced decrease in fractional urinary sodium excretion in maternal protein-restricted offspring, compared with the NP age-matched group. This occurred despite unchanged creatinine clearance. The current data led us to hypothesize that foetal undernutrition could be associated with decreased kidney expression of AT(R) resulting in the inability of renal tubules to handle the hydro-electrolyte balance, consequently causing arterial hypertension.

  3. The renal effects of SGLT2 inhibitors and a mini-review of the literature.

    Science.gov (United States)

    Andrianesis, Vasileios; Glykofridi, Spyridoula; Doupis, John

    2016-12-01

    Sodium-glucose linked transporter 2 (SGLT2) inhibitors are a new and promising class of antidiabetic agents which target renal tubular glucose reabsorption. Their action is based on the blockage of SGLT2 sodium-glucose cotransporters that are located at the luminal membrane of tubular cells of the proximal convoluted tubule, inducing glucosuria. It has been proven that they significantly reduce glycated hemoglobin (HbA1c), along with fasting and postprandial plasma glucose in patients with type 2 diabetes mellitus (T2DM). The glucosuria-induced caloric loss as well as the osmotic diuresis significantly decrease body weight and blood pressure, respectively. Given that SGLT2 inhibitors do not interfere with insulin action and secretion, their efficacy is sustained despite the progressive β-cell failure in T2DM. They are well tolerated, with a low risk of hypoglycemia. Their most frequent adverse events are minor: genital and urinal tract infections. Recently, it was demonstrated that empagliflozin presents a significant cardioprotective effect. Although the SGLT2 inhibitors' efficacy is affected by renal function, new data have been presented that some SGLT2 inhibitors, even in mild and moderate renal impairment, induce significant HbA1c reduction. Moreover, recent data indicate that SGLT2 inhibition has a beneficial renoprotective effect. The role of this review paper is to explore the current evidence on the renal effects of SGLT2 inhibitors.

  4. Effect of Cuscuta chinensis on renal function in ischemia/reperfusion-induced acute renal failure rats.

    Science.gov (United States)

    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.

  5. Hemodynamic and tubular changes induced by contrast media.

    Science.gov (United States)

    Caiazza, Antonella; Russo, Luigi; Sabbatini, Massimo; Russo, Domenico

    2014-01-01

    The incidence of acute kidney injury induced by contrast media (CI-AKI) is the third cause of AKI in hospitalized patients. Contrast media cause relevant alterations both in renal hemodynamics and in renal tubular cell function that lead to CI-AKI. The vasoconstriction of intrarenal vasculature is the main hemodynamic change induced by contrast media; the vasoconstriction is accompanied by a cascade of events leading to ischemia and reduction of glomerular filtration rate. Cytotoxicity of contrast media causes apoptosis of tubular cells with consequent formation of casts and worsening of ischemia. There is an interplay between the negative effects of contrast media on renal hemodynamics and on tubular cell function that leads to activation of renin-angiotensin system and increased production of reactive oxygen species (ROS) within the kidney. Production of ROS intensifies cellular hypoxia through endothelial dysfunction and alteration of mechanisms regulating tubular cells transport. The physiochemical characteristics of contrast media play a critical role in the incidence of CI-AKI. Guidelines suggest the use of either isoosmolar or low-osmolar contrast media rather than high-osmolar contrast media particularly in patients at increased risk of CI-AKI. Older age, presence of atherosclerosis, congestive heart failure, chronic renal disease, nephrotoxic drugs, and diuretics may multiply the risk of CI-AKI.

  6. Renal structure and function evaluation of rats from dams that received increased sodium intake during pregnancy and lactation submitted or not to 5/6 nephrectomy.

    Science.gov (United States)

    Marin, Evelyn Cristina Santana; Balbi, Ana Paula Coelho; Francescato, Heloísa Della Coletta; Alves da Silva, Cleonice Giovanini; Costa, Roberto Silva; Coimbra, Terezila M

    2008-01-01

    Adult rats submitted to perinatal salt overload presented renin-angiotensin system (RAS) functional disturbances. The RAS contributes to the renal development and renal damage in a 5/6 nephrectomy model. The aim of the present study was to analyze the renal structure and function of offspring from dams that received a high-salt intake during pregnancy and lactation. We also evaluated the influence of the prenatal high-salt intake on the evolution of 5/6 nephrectomy in adult rats. A total of 111 sixty-day-old rat pups from dams that received saline or water during pregnancy and lactation were submitted to 5/6 nephrectomy (nephrectomized) or to a sham operation (sham). The animals were killed 120 days after surgery, and the kidneys were removed for immunohistochemical and histological analysis. Systolic blood pressure (SBP), albuminuria, and glomerular filtration rate (GFR) were evaluated. Increased SBP, albuminuria, and decreased GFR were observed in the rats from dams submitted to high-sodium intake before surgery. However, there was no difference in these parameters between the groups after the 5/6 nephrectomy. The scores for tubulointerstitial lesions and glomerulosclerosis were higher in the rats from the sham saline group compared to the same age control rats, but there was no difference in the histological findings between the groups of nephrectomized rats. In conclusion, our data showed that the high-salt intake during pregnancy and lactation in rats leads to structural changes in the kidney of adult offspring. However, the progression of the renal lesions after 5/6 nephrectomy was similar in both groups.

  7. Renal albumin absorption in physiology and pathology.

    Science.gov (United States)

    Birn, H; Christensen, E I

    2006-02-01

    Albumin is the most abundant plasmaprotein serving multiple functions as a carrier of metabolites, hormones, vitamins, and drugs, as an acid/base buffer, as antioxidant and by supporting the oncotic pressure and volume of the blood. The presence of albumin in urine is considered to be the result of the balance between glomerular filtration and tubular reabsorption. Albuminuria has been accepted as an independent risk factor and a marker for renal as well as cardiovascular disease, and during the past decade, evidence has suggested that albumin itself may cause progression of renal disease. Thus, the reduction of proteinuria and, in particular, albuminuria has become a target in itself to prevent deterioration of renal function. Studies have shown albumin and its ligands to induce expression of inflammatory and fibrogenic mediators, and it has been hypothesized that increased filtration of albumin causes excessive tubular reabsorption, resulting in inflammation and fibrosis, resulting in the loss of renal function. In addition, it is known that tubular dysfunction in itself may cause albuminuria owing to decreased reabsorption of filtered albumin, and, recently, it has been suggested that significant amounts of albumin fragments are excreted in the urine as a result of tubular degradation. Thus, although both tubular and glomerular dysfunction influences renal handling of albumin, it appears that tubular reabsorption plays a central role in mediating the effects of albumin on renal function. The present paper will review the mechanisms for tubular albumin uptake and the possible implications for the development of renal disease.

  8. Tubular closure device

    International Nuclear Information System (INIS)

    Klahn, F.C.; Nolan, J.H.; Wills, C.

    1982-01-01

    This invention relates to a closure mechanism for closing openings such as the bore of a conduit and for releasably securing members within the bore. More particularly, this invention relates to a closure mechanism for tubular irradiation surveillance specimen assembly holders used in nuclear reactors

  9. Renal and cardiovascular effects of dopamine and 7.5% sodium chloride infusion: experimental study in dogs with water restriction

    OpenAIRE

    Verderese, Marisa Aparecida Lima [UNESP; Vianna, Pedro Thadeu Galvão [UNESP; Ganem, Eliana Marisa [UNESP; Vane, Luiz Antonio [UNESP

    2003-01-01

    JUSTIFICATIVA E OBJETIVOS: É controvertido o uso da infusão de dopamina na proteção renal. O objetivo desta pesquisa foi estudar o efeito da dopamina, da solução hipertônica e da associação de ambas em cães com restrição hídrica, simulando o jejum pré-operatório. MÉTODO: Foram estudados, em 32 cães anestesiados com tiopental sódico e fentanil, os seguintes parâmetros da função renal: fluxo plasmático efetivo renal (depuração de para-aminohipurato de sódio), ritmo de filtração glomerular (depu...

  10. Is the renal kallikrein-kinin system a factor that modulates hypercalciuria?

    Directory of Open Access Journals (Sweden)

    Armando Luis Negri

    2017-01-01

    Full Text Available Renal tubular calcium reabsorption is one of the principal factors that determine serum calcium concentration and calcium excretion. Calcium excretion is regulated by the distal convoluted tubule and connecting tubule, where the epithelial calcium channel TRPV5 can be found, which limits the rate of transcellular calcium transport. The dynamic presence of the TRPV5 channel on the surface of the tubular cell is mediated by an endosomal recycling process. Different intrarenal factors are involved in calcium channel fixation in the apical membrane, including the anti-ageing hormone klotho and tissue kallikrein (TK. Both proteins are synthesised in the distal tubule and secreted in the tubular fluid. TK stimulates active calcium reabsorption through the bradykinin receptor B2 that compromises TRPV5 activation through the protein kinase C pathway. TK-deficient mice show hypercalciuria of renal origin comparable to that seen in TRPV5 knockout mice. There is a polymorphism with loss of function of the human TK gene R53H (allele H that causes a marked decrease in enzymatic activity. The presence of the allele H seems to be common at least in the Japanese population (24%. These individuals have a tendency to greater calcium and sodium excretion in urine that is more evident during furosemide infusion. Future studies should analyse if manipulating the renal kallikrein-kinin system can correct idiopathic hypercalciuria with drugs other than thiazide diuretics.

  11. Tubular transport and metabolism of cimetidine in chicken kidneys

    International Nuclear Information System (INIS)

    Rennick, B.; Ziemniak, J.; Smith, I.; Taylor, M.; Acara, M.

    1984-01-01

    Renal tubular transport and renal metabolism of [ 14 C]cimetidine (CIM) were investigated by unilateral infusion into the renal portal circulation in chickens (Sperber technique). [ 14 C]CIM was actively transported at a rate 88% that of simultaneously infused p-aminohippuric acid, and its transport was saturable. The following organic cations competitively inhibited the tubular transport of [ 14 C]CIM with decreasing potency: CIM, ranitidine, thiamine, procainamide, guanidine and choline. CIM inhibited the transport of [ 14 C]thiamine, [ 14 C]amiloride and [ 14 C]tetraethylammonium. During CIM infusion, two renal metabolites, CIM sulfoxide and hydroxymethylcimetidine, were found in urine. When CIM sulfoxide was infused, its transport efficiency was 32% and not saturable. CIM sulfoxide did ot inhibit the simultaneous renal tubular transport of p-aminohippuric acid or tetraethylammonium. CIM is transported by the organic cation transport system and the kidney metabolizes CIM. Transport of CIM and other cationic drugs could produce a drug interaction to alter drug excretion

  12. Acute tubular necrosis in a patient with paroxysmal nocturnal hemoglobinuria

    Directory of Open Access Journals (Sweden)

    Eranga S Wijewickrama

    2013-01-01

    Full Text Available Acute renal failure (ARF is a well-recognized complication of paroxysmal nocturnal hemoglobinuria (PNH. The predominant mechanism is intravascular hemolysis resulting in massive hemoglobinuria ARF. We report a case of acute tubular necrosis (ATN developed in the absence of overwhelming evidence of intravascular hemolysis in a 21-year-old man with anemia, who was eventually diagnosed to have PNH. The patient presented with rapidly deteriorating renal functions in the background of iron deficiency anemia, which was attributed to reflux esophagitis. There was no clinical or laboratory evidence of intravascular hemolysis. Renal biopsy revealed ATN with deposition of hemosiderin in the proximal tubular epithelial cells. Diagnosis of PNH was confirmed with a positive Ham′s test and flow cytometry. Our case emphasizes the need to consider ATN as a possible cause for ARF in patients suspected to have PNH even in the absence of overwhelming evidence of intravascular hemolysis.

  13. Role of the Sympathetic Nervous System and Its Modulation in Renal Hypertension.

    Science.gov (United States)

    Sata, Yusuke; Head, Geoffrey A; Denton, Kate; May, Clive N; Schlaich, Markus P

    2018-01-01

    The kidneys are densely innervated with renal efferent and afferent nerves to communicate with the central nervous system. Innervation of major structural components of the kidneys, such as blood vessels, tubules, the pelvis, and glomeruli, forms a bidirectional neural network to relay sensory and sympathetic signals to and from the brain. Renal efferent nerves regulate renal blood flow, glomerular filtration rate, tubular reabsorption of sodium and water, as well as release of renin and prostaglandins, all of which contribute to cardiovascular and renal regulation. Renal afferent nerves complete the feedback loop via central autonomic nuclei where the signals are integrated and modulate central sympathetic outflow; thus both types of nerves form integral parts of the self-regulated renorenal reflex loop. Renal sympathetic nerve activity (RSNA) is commonly increased in pathophysiological conditions such as hypertension and chronic- and end-stage renal disease. Increased RSNA raises blood pressure and can contribute to the deterioration of renal function. Attempts have been made to eliminate or interfere with this important link between the brain and the kidneys as a neuromodulatory treatment for these conditions. Catheter-based renal sympathetic denervation has been successfully applied in patients with resistant hypertension and was associated with significant falls in blood pressure and renal protection in most studies performed. The focus of this review is the neural contribution to the control of renal and cardiovascular hemodynamics and renal function in the setting of hypertension and chronic kidney disease, as well as the specific roles of renal efferent and afferent nerves in this scenario and their utility as a therapeutic target.

  14. Role of the Sympathetic Nervous System and Its Modulation in Renal Hypertension

    Directory of Open Access Journals (Sweden)

    Yusuke Sata

    2018-03-01

    Full Text Available The kidneys are densely innervated with renal efferent and afferent nerves to communicate with the central nervous system. Innervation of major structural components of the kidneys, such as blood vessels, tubules, the pelvis, and glomeruli, forms a bidirectional neural network to relay sensory and sympathetic signals to and from the brain. Renal efferent nerves regulate renal blood flow, glomerular filtration rate, tubular reabsorption of sodium and water, as well as release of renin and prostaglandins, all of which contribute to cardiovascular and renal regulation. Renal afferent nerves complete the feedback loop via central autonomic nuclei where the signals are integrated and modulate central sympathetic outflow; thus both types of nerves form integral parts of the self-regulated renorenal reflex loop. Renal sympathetic nerve activity (RSNA is commonly increased in pathophysiological conditions such as hypertension and chronic- and end-stage renal disease. Increased RSNA raises blood pressure and can contribute to the deterioration of renal function. Attempts have been made to eliminate or interfere with this important link between the brain and the kidneys as a neuromodulatory treatment for these conditions. Catheter-based renal sympathetic denervation has been successfully applied in patients with resistant hypertension and was associated with significant falls in blood pressure and renal protection in most studies performed. The focus of this review is the neural contribution to the control of renal and cardiovascular hemodynamics and renal function in the setting of hypertension and chronic kidney disease, as well as the specific roles of renal efferent and afferent nerves in this scenario and their utility as a therapeutic target.

  15. Combination Therapy with Losartan and Pioglitazone Additively Reduces Renal Oxidative and Nitrative Stress Induced by Chronic High Fat, Sucrose, and Sodium Intake

    Directory of Open Access Journals (Sweden)

    Xiang Kong

    2012-01-01

    Full Text Available We recently showed that combination therapy with losartan and pioglitazone provided synergistic effects compared with monotherapy in improving lesions of renal structure and function in Sprague-Dawley rats fed with a high-fat, high-sodium diet and 20% sucrose solution. This study was designed to explore the underlying mechanisms of additive renoprotection provided by combination therapy. Losartan, pioglitazone, and their combination were orally administered for 8 weeks. The increased level of renal malondialdehyde and expression of nicotinamide adenine dinucleotide phosphate oxidase subunit p47phox and nitrotyrosine as well as the decreased total superoxide dismutase activity and copper, zinc-superoxide dismutase expression were tangible evidence for the presence of oxidative and nitrative stress in the kidney of model rats. Treatment with both drugs, individually and in combination, improved these abnormal changes. Combination therapy showed synergistic effects in reducing malondialdehyde level, p47phox, and nitrotyrosine expression to almost the normal level compared with monotherapy. All these results suggest that the additive renoprotection provided by combination therapy might be attributed to a further reduction of oxidative and nitrative stress.

  16. Experimental dissociation of the effects of prostaglandins on renal sodium and water reabsorption by cyclo-oxygenase inhibitors in the rat.

    Science.gov (United States)

    Bartoli, E; Branca, G F; Faedda, R; Olmeo, N A; Satta, A; Soggia, G

    1982-07-01

    1 The relative importance of the effect of prostaglandins on renal sodium and water reabsorption was assessed in rats. 2 Clearance experiments were performed on 24 anaesthetized rats divided into 3 groups. Each group was infused throughout either with Ringer solution at 9 ml/h (Protocol I), or at 3 ml/h (Protocol II) or with hypotonic fluid at 5 ml/h (Protocol III). Clearance periods were performed before and after intravenous injection of indomethacin (5 mg/kg) and then of aspirin (20 mg/kg). The natriuretic response to different degrees of volume expansion was not modified during the action of the inhibitors. 3 When baseline urine osmolality (Uosm) was high (Protocol II) no further increase occurred in the presence of prostaglandin inhibition. Conversely, Uosm rose from 771 +/- 134 to 1356 +/- 414 and from 575 +/- 245 to 841 +/- 407 mosm/kg (P less than 0.05) in Protocol I and Protocol III respectively, when antidiuretic hormone secretion was inhibited by the higher degree of volume expansion. 4 There was a significant correlation between the change in urine flow rate induced by cyclooxygenase inhibitors and the attendant variations in Na excretion, r = 0.42, n = 41, P less than 0.01. 5 Thus, prostaglandins affect Na loss during saline load as a side effect of their action on water permeability. They could play an important role in volume depletion by counterbalancing the large secretion rate of renal vasoconstrictors.

  17. Experimental dissociation of the effects of prostaglandins on renal sodium and water reabsorption by cyclo-oxygenase inhibitors in the rat.

    Science.gov (United States)

    Bartoli, E.; Branca, G. F.; Faedda, R.; Olmeo, N. A.; Satta, A.; Soggia, G.

    1982-01-01

    1 The relative importance of the effect of prostaglandins on renal sodium and water reabsorption was assessed in rats. 2 Clearance experiments were performed on 24 anaesthetized rats divided into 3 groups. Each group was infused throughout either with Ringer solution at 9 ml/h (Protocol I), or at 3 ml/h (Protocol II) or with hypotonic fluid at 5 ml/h (Protocol III). Clearance periods were performed before and after intravenous injection of indomethacin (5 mg/kg) and then of aspirin (20 mg/kg). The natriuretic response to different degrees of volume expansion was not modified during the action of the inhibitors. 3 When baseline urine osmolality (Uosm) was high (Protocol II) no further increase occurred in the presence of prostaglandin inhibition. Conversely, Uosm rose from 771 +/- 134 to 1356 +/- 414 and from 575 +/- 245 to 841 +/- 407 mosm/kg (P less than 0.05) in Protocol I and Protocol III respectively, when antidiuretic hormone secretion was inhibited by the higher degree of volume expansion. 4 There was a significant correlation between the change in urine flow rate induced by cyclooxygenase inhibitors and the attendant variations in Na excretion, r = 0.42, n = 41, P less than 0.01. 5 Thus, prostaglandins affect Na loss during saline load as a side effect of their action on water permeability. They could play an important role in volume depletion by counterbalancing the large secretion rate of renal vasoconstrictors. PMID:6809089

  18. Maternal drugs and neonatal renal failure

    Directory of Open Access Journals (Sweden)

    M Sahay

    2014-01-01

    Full Text Available Maternal use of drugs during pregnancy may cause irreversible renal failure in the newborn. This report highlights the adverse effect of telmisartan during the last trimester of pregnancy. The neonate presented with oliguric renal failure and the renal histology showed proximal tubular dysgenesis.

  19. Norepinephrine-evoked salt-sensitive hypertension requires impaired renal sodium chloride cotransporter activity in Sprague-Dawley rats.

    Science.gov (United States)

    Walsh, Kathryn R; Kuwabara, Jill T; Shim, Joon W; Wainford, Richard D

    2016-01-15

    Recent studies have implicated a role of norepinephrine (NE) in the activation of the sodium chloride cotransporter (NCC) to drive the development of salt-sensitive hypertension. However, the interaction between NE and increased salt intake on blood pressure remains to be fully elucidated. This study examined the impact of a continuous NE infusion on sodium homeostasis and blood pressure in conscious Sprague-Dawley rats challenged with a normal (NS; 0.6% NaCl) or high-salt (HS; 8% NaCl) diet for 14 days. Naïve and saline-infused Sprague-Dawley rats remained normotensive when placed on HS and exhibited dietary sodium-evoked suppression of peak natriuresis to hydrochlorothiazide. NE infusion resulted in the development of hypertension, which was exacerbated by HS, demonstrating the development of the salt sensitivity of blood pressure [MAP (mmHg) NE+NS: 151 ± 3 vs. NE+HS: 172 ± 4; P salt-sensitive animals, increased NE prevented dietary sodium-evoked suppression of peak natriuresis to hydrochlorothiazide, suggesting impaired NCC activity contributes to the development of salt sensitivity [peak natriuresis to hydrochlorothiazide (μeq/min) Naïve+NS: 9.4 ± 0.2 vs. Naïve+HS: 7 ± 0.1; P salt-sensitive component of NE-mediated hypertension, while chronic ANG II type 1 receptor antagonism significantly attenuated NE-evoked hypertension without restoring NCC function. These data demonstrate that increased levels of NE prevent dietary sodium-evoked suppression of the NCC, via an ANG II-independent mechanism, to stimulate the development of salt-sensitive hypertension. Copyright © 2016 the American Physiological Society.

  20. Comparison of sodium, potassium, calcium, magnesium, zinc, copper and iron concentrations of elements in 24-h urine and spot urine in hypertensive patients with healthy renal function.

    Science.gov (United States)

    Zhang, Tianjing; Chang, Xiaoyu; Liu, Wanlu; Li, Xiaoxia; Wang, Faxuan; Huang, Liping; Liao, Sha; Liu, Xiuying; Zhang, Yuhong; Zhao, Yi

    2017-12-01

    Sodium, potassium, calcium, magnesium, zinc, copper and iron are associated with the sequela of hypertension. The most reliable method for testing those elements is by collecting 24-h urine samples. However, this is cumbersome and collection of spot urine is more convenient in some circumstance. The aim of this study was to compare the concentrations of different elements in 24-h urine and spot urine. Data was collected from a sub-study of China Salt Substitute and Stroke Study. 240 participants were recruited randomly from 12 villages in two counties in Ningxia, China. Both spot and 24-h urine specimens were collected from each patient. Routine urine test was conducted, and concentration of elements was measured using microwave digestion and Inductively Coupled Plasma-Optical Emission Spectrometry. Partial correlation analysis and Spearman correlation analysis were used to investigate the concentration of different elements and the relationship between 24- h urine and spot urine. A partial correlation in sodium, potassium, calcium, magnesium and iron was found between paired 24-h urine and spot urine samples except copper and zinc: 0.430, 0.426, 0.550, 0.221 and 0.191 respectively. Spot urine can replace 24-h urine for estimating some of the elements in hypertensive patients with normal renal function. Copyright © 2017 Elsevier GmbH. All rights reserved.

  1. Deregulated Renal Calcium and Phosphate Transport during Experimental Kidney Failure.

    Directory of Open Access Journals (Sweden)

    Wilco P Pulskens

    Full Text Available Impaired mineral homeostasis and inflammation are hallmarks of chronic kidney disease (CKD, yet the underlying mechanisms of electrolyte regulation during CKD are still unclear. Here, we applied two different murine models, partial nephrectomy and adenine-enriched dietary intervention, to induce kidney failure and to investigate the subsequent impact on systemic and local renal factors involved in Ca(2+ and Pi regulation. Our results demonstrated that both experimental models induce features of CKD, as reflected by uremia, and elevated renal neutrophil gelatinase-associated lipocalin (NGAL expression. In our model kidney failure was associated with polyuria, hypercalcemia and elevated urinary Ca(2+ excretion. In accordance, CKD augmented systemic PTH and affected the FGF23-αklotho-vitamin-D axis by elevating circulatory FGF23 levels and reducing renal αklotho expression. Interestingly, renal FGF23 expression was also induced by inflammatory stimuli directly. Renal expression of Cyp27b1, but not Cyp24a1, and blood levels of 1,25-dihydroxy vitamin D3 were significantly elevated in both models. Furthermore, kidney failure was characterized by enhanced renal expression of the transient receptor potential cation channel subfamily V member 5 (TRPV5, calbindin-D28k, and sodium-dependent Pi transporter type 2b (NaPi2b, whereas the renal expression of sodium-dependent Pi transporter type 2a (NaPi2a and type 3 (PIT2 were reduced. Together, our data indicates two different models of experimental kidney failure comparably associate with disturbed FGF23-αklotho-vitamin-D signalling and a deregulated electrolyte homeostasis. Moreover, this study identifies local tubular, possibly inflammation- or PTH- and/or FGF23-associated, adaptive mechanisms, impacting on Ca(2+/Pi homeostasis, hence enabling new opportunities to target electrolyte disturbances that emerge as a consequence of CKD development.

  2. Dual effect of chemokine CCL7/MCP-3 in the development of renal tubulointerstitial fibrosis

    NARCIS (Netherlands)

    Gonzalez, Julien; Mouttalib, Sofia; Delage, Christine; Calise, Denis; Maoret, Jean-Jose; Pradere, Jean-Philippe; Klein, Julie; Buffin-Meyer, Benedicte; Van der Veen, Betty; Charo, Israel F.; Heeringa, Peter; Duchene, Johan; Bascands, Jean-Loup; Schanstra, Joost-Peter

    2013-01-01

    Most end-stage renal disease kidneys display accumulation of extracellular matrix (ECM) in the renal tubular compartment (tubular interstitial fibrosis - TIF) which is strongly correlated with the future loss of renal function. Although inflammation is a key event in the development of TIF, it can

  3. The Role of Hydrogen Sulfide in Renal System.

    Science.gov (United States)

    Cao, Xu; Bian, Jin-Song

    2016-01-01

    Hydrogen sulfide has gained recognition as the third gaseous signaling molecule after nitric oxide and carbon monoxide. This review surveys the emerging role of H 2 S in mammalian renal system, with emphasis on both renal physiology and diseases. H 2 S is produced redundantly by four pathways in kidney, indicating the abundance of this gaseous molecule in the organ. In physiological conditions, H 2 S was found to regulate the excretory function of the kidney possibly by the inhibitory effect on sodium transporters on renal tubular cells. Likewise, it also influences the release of renin from juxtaglomerular cells and thereby modulates blood pressure. A possible role of H 2 S as an oxygen sensor has also been discussed, especially at renal medulla. Alternation of H 2 S level has been implicated in various pathological conditions such as renal ischemia/reperfusion, obstructive nephropathy, diabetic nephropathy, and hypertensive nephropathy. Moreover, H 2 S donors exhibit broad beneficial effects in renal diseases although a few conflicts need to be resolved. Further research reveals that multiple mechanisms are underlying the protective effects of H 2 S, including anti-inflammation, anti-oxidation, and anti-apoptosis. In the review, several research directions are also proposed including the role of mitochondrial H 2 S in renal diseases, H 2 S delivery to kidney by targeting D-amino acid oxidase/3-mercaptopyruvate sulfurtransferase (DAO/3-MST) pathway, effect of drug-like H 2 S donors in kidney diseases and understanding the molecular mechanism of H 2 S. The completion of the studies in these directions will not only improves our understanding of renal H 2 S functions but may also be critical to translate H 2 S to be a new therapy for renal diseases.

  4. The phosphaturic effect of sodium bicarbonate and acetazolamide in dogs

    Science.gov (United States)

    Fulop, Milford; Brazeau, Paul

    1968-01-01

    Urinary inorganic phosphate excretion was studied before and during the administration of sodium bicarbonate and acetazolamide in dogs that were not given infusions of phosphate. The excretion fraction of filtered phosphate increased after sodium bicarbonate or acetazolamide was given. This phosphaturia was attributed to decreased tubular reabsorption of phosphate consequent to alkalinization of either tubular urine or cells. PMID:5645865

  5. Kidney injury molecule-1 in renal disease

    NARCIS (Netherlands)

    Waanders, Femke; van Timmeren, Mirjan M.; Stegeman, Coen A.; Bakker, Stephan J. L.; van Goor, Harry

    Kidney injury molecule-1 (KIM-1) is a marker for renal proximal tubular damage, the hallmark of virtually all proteinuric, toxic and ischaemic kidney diseases. KIM-1 has gained increasing interest because of its possible pathophysiological role in modulating tubular damage and repair. In this

  6. Tubular closure mechanism

    International Nuclear Information System (INIS)

    Kalen, D.D.; Mitchem, J.W.

    1982-01-01

    This invention relates to a closure mechanism for tubular irradiation surveillance specimen assembly holder used in nuclear reactors. The closure mechanism is composed of a latching member which includes a generally circular chamber with a plurality of elongated latches depending therefrom. The latching member circumscribes part of an actuator member which is disposed within the latching member so as to be axially movable. The axial movement of the actuator actuates positioning of the latches between positions in which the latches are locked and secured within the actuator member. Means, capable of being remotely manipulated, are provided to move the actuator in order to position the latches and load the articles within the tube

  7. Urinary Markers of Tubular Injury in Early Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Temesgen Fiseha

    2016-01-01

    Full Text Available Diabetic nephropathy (DN is a common and serious complication of diabetes associated with adverse outcomes of renal failure, cardiovascular disease, and premature mortality. Early and accurate identification of DN is therefore of critical importance to improve patient outcomes. Albuminuria, a marker of glomerular involvement in early renal damage, cannot always detect early DN. Thus, more sensitive and specific markers in addition to albuminuria are needed to predict the early onset and progression of DN. Tubular injury, as shown by the detection of tubular injury markers in the urine, is a critical component of the early course of DN. These urinary tubular markers may increase in diabetic patients, even before diagnosis of microalbuminuria representing early markers of normoalbuminuric DN. In this review we summarized some new and important urinary markers of tubular injury, such as neutrophil gelatinase associated lipocalin (NGAL, kidney injury molecule-1 (KIM-1, liver-type fatty acid binding protein (L-FABP, N-acetyl-beta-glucosaminidase (NAG, alpha-1 microglobulin (A1M, beta 2-microglobulin (B2-M, and retinol binding protein (RBP associated with early DN.

  8. Proximal tubular dysfunction as an indicator of chronic graft dysfunction

    Directory of Open Access Journals (Sweden)

    N.O.S. Câmara

    2009-03-01

    Full Text Available New strategies are being devised to limit the impact of renal sclerosis on graft function. Individualization of immunosuppression, specifically the interruption of calcineurin-inhibitors has been tried in order to promote better graft survival once chronic graft dysfunction has been established. However, the long-term impact of these approaches is still not totally clear. Nevertheless, patients at higher risk for tubular atrophy and interstitial fibrosis (TA/IF development should be carefully monitored for tubular function as well as glomerular performance. Since tubular-interstitial impairment is an early event in TA/IF pathogenesis and associated with graft function, it seems reasonable that strategies directed at assessing tubular structural integrity and function would yield important functional and prognostic data. The measurement of small proteins in urine such as α-1-microglobulin, N-acetyl-beta-D-glucosaminidase, alpha/pi S-glutathione transferases, β-2 microglobulin, and retinol binding protein is associated with proximal tubular cell dysfunction. Therefore, its straightforward assessment could provide a powerful tool in patient monitoring and ongoing clinical assessment of graft function, ultimately helping to facilitate longer patient and graft survival associated with good graft function.

  9. [Effects of sodium ethamsylate on anticoagulant and anti-aggregation activity of vascular endothelium in hemorrhagic fever patients with renal syndrome].

    Science.gov (United States)

    Davidovich, I M; Sirotin, B Z; Parshina, T A

    1999-01-01

    To elucidate effects of sodium ethamsylate (SE) on anticoagulant and antiaggregation activity of vascular endothelium in patients suffering from hemorrhagic fever with renal syndrome (HFRS). A trial of SE enrolled 70 HFRS patients (58 males, 12 females aged under 30 years) compatible by the disease severity. They were divided into two groups. 42 patients of the control group received standard therapy, 28 patients of the study group received adjuvant 12% solution of SE in daily dose 1500-2000 mg in the course of HFRS oliguria period. Hemostatic parameters were measured before and after the cuff test to investigate the condition of vascular wall with calculation of the athrombogenicity index (the ratio of the relevant indices before and after the cuff test). SE effects on vascular endothelium was assessed by a blind method. In oliguria, both groups had baseline antiaggregation indices significantly higher than in the control. After the cuff test, control patients' indices tended to an increase while in the study group there was a marked decrease. The trend in anticoagulant activity of microvascular endothelium did not differ much with the groups. This picture persisted also in polyuria. In convalescence hemostasis was similar in both groups. SE enhances antiaggregant activity of vascular endothelium in oliguria period of HFRS without affecting its anticoagulant properties. This is explained by a direct effect of SE on vascular endothelium.

  10. Expandable tubulars for use in geologic structures

    Science.gov (United States)

    Spray, Jeffery A.; Svedeman, Steven; Walter, David; Mckeighan, Peter; Siebanaler, Shane; Dewhurst, Peter; Hobson, Steven; Foss, Doug; Wirz, Holger; Sharpe, Aaron; Apostal, Michael

    2014-08-12

    An expandable tubular includes a plurality of leaves formed from sheet material that have curved surfaces. The leaves extend around a portion or fully around the diameter of the tubular structure. Some of the adjacent leaves of the tubular are coupled together. The tubular is compressed to a smaller diameter so that it can be inserted through previously deployed tubular assemblies. Once the tubular is properly positioned, it is deployed and coupled or not coupled to a previously deployed tubular assembly. The tubular is useful for all types of wells and boreholes.

  11. Tubular closure mechanism

    International Nuclear Information System (INIS)

    Kalen, D.D.; Mitchem, J.W.

    1981-01-01

    An apparatus is provided for closing the bore of a tube and releasably securing articles within the tube under longitudinal load. A latching member has a cylindrical section and several circumferentially-spaced elongated latches hanging down from one end of the cylinder. An elongated actuator has integral cam and spline and is partly located within the latch with the cam radially contacting the latches and the spline projecting into the circumferential spaces between the latches. The actuator is axially movable between a position in which the latches are locked to the tube walls and a position in which the latches are secured from contact with the tube walls. Means are provided for axially moving the actuator such that the cam positions the latches; and means are also provided for engaging the articles within the tube. The closure is particularly applicable to tubular irradiation surveillance specimen assembly holders used in reactors

  12. Effects of acute hypoxia on renal and endocrine function at rest and during graded exercise in hydrated subjects

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Kanstrup, I L; Richalet, J P

    1992-01-01

    Renal effects of altitude hypoxia are unclear. Renal and hormonal function was investigated in eight males at rest and during graded exercise at sea level (SL) and 48 h after rapid ascent to 4,350 m (HA). HA did not change resting values of effective renal plasma flow (ERPF), glomerular filtration...... rate (GFR), sodium clearance (CNa), urine flow, or lithium clearance (CLi), which was used as an index of proximal tubular outflow. At rest, HA increased plasma norepinephrine concentration and decreased plasma concentrations of renin and aldosterone. Exercise decreased ERPF similarly in both...... environments. Normoxic exercise progressively reduced GFR, but at HA GFR only decreased during heavy exercise. This resulted in a higher filtration fraction during light and moderate hypoxic exercise. However, calculated absolute proximal reabsorption rate (GFR-CLi) at HA was higher during low...

  13. Effect of tubular damage by mercuric chloride on kidney function and some urinary enzymes in the dog

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, B G; Price, R G; Topham, J C

    1973-01-01

    Alkaline and acid phosphatases, ..beta..-glucosidase, ..beta..-galactosidase, N-acetyl-..beta..-glucosaminidase and lactate dehydrogenase were monitored in the urine and serum of dogs with renal tubular damage induced by a series of increasing doses of mercuric chloride. Evidence is presented that the assay of urinary alkaline and acid phosphatase is the most sensitive method of detecting renal tubular damage in the dog. The clearance of (/sup 14/C)-propranolol was compared before and after the administration of mercuric chloride. In the presence of tubular damage the blood half-life of propranolol and the rate of excretion of metabolites in the urine were increased. 35 references, 7 tables.

  14. Angiotensin 2 directly increases rabbit renal brush-border membrane sodium transport: Presence of local signal transduction system

    Energy Technology Data Exchange (ETDEWEB)

    Morduchowicz, G.A.; Sheikh-Hamad, D.; Dwyer, B.E.; Stern, N.; Jo, O.D.; Yanagawa, N. (Sepulveda Veterans Administration, CA (USA))

    1991-05-01

    In the present study, the authors have examined the direct actions of angiotensin II (AII) in rabbit renal brush border membrane (BBM) where binding sites for AII exist. Addition of AII (10(-11)-10(-7) M) was found to stimulate 22Na+ uptake by the isolated BBM vesicles directly. All did not affect the Na(+)-dependent BBM glucose uptake, and the effect of AII on BBM 22Na+ uptake was inhibited by amiloride, suggesting the involvement of Na+/H+ exchange mechanism. BBM proton permeability as assessed by acridine orange quenching was not affected by AII, indicating the direct effect of AII on Na+/H+ antiport system. In search of the signal transduction mechanism, it was found that AII activated BBM phospholipase A2 (PLA) and that BBM contains a 42-kDa guanine nucleotide-binding regulatory protein (G-protein) that underwent pertussis toxin (PTX)-catalyzed ADP-ribosylation. Addition of GTP potentiated, while GDP-beta S or PTX abolished, the effects of AII on BBM PLA and 22Na+ uptake, suggesting the involvement of G-protein in AII's actions. On the other hand, inhibition of PLA by mepacrine prevented AII's effect on BBM 22Na+ uptake, and activation of PLA by mellitin or addition of arachidonic acid similarly enhanced BBM 22Na+ uptake, suggesting the role of PLA activation in mediating AII's effect on BBM 22Na+ uptake. In summary, results of the present study show a direct stimulatory effect of AII on BBM Na+/H+ antiport system, and suggest the presence of a local signal transduction system involving G-protein mediated PLA activation.

  15. Angiotensin 2 directly increases rabbit renal brush-border membrane sodium transport: Presence of local signal transduction system

    International Nuclear Information System (INIS)

    Morduchowicz, G.A.; Sheikh-Hamad, D.; Dwyer, B.E.; Stern, N.; Jo, O.D.; Yanagawa, N.

    1991-01-01

    In the present study, the authors have examined the direct actions of angiotensin II (AII) in rabbit renal brush border membrane (BBM) where binding sites for AII exist. Addition of AII (10(-11)-10(-7) M) was found to stimulate 22Na+ uptake by the isolated BBM vesicles directly. All did not affect the Na(+)-dependent BBM glucose uptake, and the effect of AII on BBM 22Na+ uptake was inhibited by amiloride, suggesting the involvement of Na+/H+ exchange mechanism. BBM proton permeability as assessed by acridine orange quenching was not affected by AII, indicating the direct effect of AII on Na+/H+ antiport system. In search of the signal transduction mechanism, it was found that AII activated BBM phospholipase A2 (PLA) and that BBM contains a 42-kDa guanine nucleotide-binding regulatory protein (G-protein) that underwent pertussis toxin (PTX)-catalyzed ADP-ribosylation. Addition of GTP potentiated, while GDP-beta S or PTX abolished, the effects of AII on BBM PLA and 22Na+ uptake, suggesting the involvement of G-protein in AII's actions. On the other hand, inhibition of PLA by mepacrine prevented AII's effect on BBM 22Na+ uptake, and activation of PLA by mellitin or addition of arachidonic acid similarly enhanced BBM 22Na+ uptake, suggesting the role of PLA activation in mediating AII's effect on BBM 22Na+ uptake. In summary, results of the present study show a direct stimulatory effect of AII on BBM Na+/H+ antiport system, and suggest the presence of a local signal transduction system involving G-protein mediated PLA activation

  16. Efeitos da efedrina sobre as funções cardiovascular e renal de cães sob anestesia com pentobarbital sódico Efectos de la efedrina sobre las funciones cardiovascular y renal de perros bajo anestesia con pentobarbital sódico Effects of rphedrine on cardiovascular and renal function of dogs anesthetized with sodium pentobarbital

    Directory of Open Access Journals (Sweden)

    Rosa Beatriz Amorim

    2002-07-01

    verifying whether different ephedrine doses determine differentiated hemodynamic and renal effects. METHODS: Cardiovascular and renal hemodynamics and renal function were evaluated in 32 dogs anesthetized with sodium pentobarbital (SP for surgical preparation, catheterization, extracellular fluid volume expansion and mechanical ventilation. Dogs were randomly distributed in four groups: G control (n = 8, in which dogs remained only under the effect of SP; G ephedrine 2 µg (n = 8; G ephedrine 10 µg (n = 8; and G ephedrine 100 µg (n = 8, in which dogs received 2, 10, and 100 µg.kg-1.min-1 ephedrine, respectively. Cardiovascular and renal parameters were studied at control (M1 and M2, during ephedrine infusion (M3 and M4 and after ephedrine infusion withdrawal (M5. RESULTS: There were no significant differences among groups. There has been a significant increase in heart rate, aortic blood flow, urinary output and fractional sodium excretion in G ephedrine 2 µg. There has been a significant increase in heart rate and filtration fraction in G ephedrine 10 µg while in G ephedrine 100 µg there has been a significant increase in heart rate, mean blood pressure, aortic blood flow, central venous pressure, renal vascular resistance and hematocrit, and a significant decrease in renal plasma and blood flow. CONCLUSIONS: Our study has shown that ephedrine has differentiated dose-dependent hemodynamic and renal effects.

  17. The effect of acyclovir on the tubular secretion of creatinine in vitro

    Directory of Open Access Journals (Sweden)

    Aleksa Katarina

    2010-12-01

    Full Text Available Abstract Background While generally well tolerated, severe nephrotoxicity has been observed in some children receiving acyclovir. A pronounced elevation in plasma creatinine in the absence of other clinical manifestations of overt nephrotoxicity has been frequently documented. Several drugs have been shown to increase plasma creatinine by inhibiting its renal tubular secretion rather than by decreasing glomerular filtration rate (GFR. Creatinine and acyclovir may be transported by similar tubular transport mechanisms, thus, it is plausible that in some cases, the observed increase in plasma creatinine may be partially due to inhibition of tubular secretion of creatinine, and not solely due to decreased GFR. Our objective was to determine whether acyclovir inhibits the tubular secretion of creatinine. Methods Porcine (LLC-PK1 and human (HK-2 renal proximal tubular cell monolayers cultured on microporous membrane filters were exposed to [2-14C] creatinine (5 μM in the absence or presence of quinidine (1E+03 μM, cimetidine (1E+03 μM or acyclovir (22 - 89 μM in incubation medium. Results Results illustrated that in evident contrast to quinidine, acyclovir did not inhibit creatinine transport in LLC-PK1 and HK-2 cell monolayers. Conclusions The results suggest that acyclovir does not affect the renal tubular handling of creatinine, and hence, the pronounced, transient increase in plasma creatinine is due to decreased GFR, and not to a spurious increase in plasma creatinine.

  18. Sodium intake modifies the negative prognostic value of renal damage prior to treatment with ACE inhibitors on proteinuria induced by adriamycin

    NARCIS (Netherlands)

    Kramer, Andrea B.; Bos, Hendrik; van Goor, Harry; Navis, Gerjan J.

    2006-01-01

    Background: Antiproteinuric treatment by ACE inhibition (ACEi) provides renoprotection. However, resistance to antiproteinuric intervention occurs frequently, resulting in progressive renal damage. The extent of renal damage prior to treatment with ACEi reversely correlates with the antiproteinuric

  19. OBESITY-INDUCED HYPERTENSION: INTERACTION OF NEUROHUMORAL AND RENAL MECHANISMS

    Science.gov (United States)

    Hall, John E.; do Carmo, Jussara M.; da Silva, Alexandre A.; Wang, Zhen; Hall, Michael E.

    2015-01-01

    Excess weight gain, especially when associated with increased visceral adiposity, is a major cause of hypertension, accounting for 65–75% of the risk for human primary (essential) hypertension. Increased renal tubular sodium reabsorption impairs pressure natriuresis and plays an important role in initiating obesity hypertension. The mediators of abnormal kidney function and increased blood pressure during development of obesity hypertension include 1) physical compression of the kidneys by fat in and around the kidneys, 2) activation of the renin-angiotensin-aldosterone system (RAAS), and 3) increased sympathetic nervous system (SNS) activity. Activation of the RAAS system is likely due, in part, to renal compression as well as SNS activation. However, obesity also causes mineralocorticoid receptor activation independent of aldosterone or angiotensin II. The mechanisms for SNS activation in obesity have not been fully elucidated but appear to require leptin and activation of the brain melanocortin system. With prolonged obesity and development of target organ injury, especially renal injury, obesity-associated hypertension becomes more difficult to control, often requiring multiple antihypertensive drugs and treatment of other risk factors, including dyslipidemia, insulin resistance and diabetes, and inflammation. Unless effective anti-obesity drugs are developed, the impact of obesity on hypertension and related cardiovascular, renal and metabolic disorders is likely to become even more important in the future as the prevalence of obesity continues to increase. PMID:25767285

  20. Mathematical Model of Ammonia Handling in the Rat Renal Medulla

    Science.gov (United States)

    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

  1. Efficacy of ultrasonography-guided renal biopsy for the evaluation of renal dysfunction following renal transplantation

    International Nuclear Information System (INIS)

    Kim, Young Jae; Choi, Chul Soon; Min, Seon Jeong; Lee, Gyung Kyu; Lee, Eil Seong; Kang, Ik Won; Bae, Sang Hoon

    2003-01-01

    To evaluate the usefulness and complications of renal biopsy under ultrasonography-guidance in renal dysfunction after renal transplantation. Ultrasonography-guided renal biopsy was done in 47 patients with the transplanted kidney. The subjects consisted of 30 males and 17 females, age ranged from 16 to 66 years (average age=38 years). Biopsies were done once in 27 patients, twice in 17 patients, three times in 3 patients, a total of 70 biopsies. The success rate of renal biopsy for the accurate pathologic diagnosis and the incidence and types of complications following biopsy were evaluated. The success rate of renal biopsy for the accurate pathologic diagnosis was 96%(67/70). Pathologic diagnosis included 27 cases of acute rejection (39%), 8 cases of acute tubular necrosis (11%), 4 cases of acute rejection and acute tubular necrosis (6%), 4 cases of cyclosporin toxicity (6%), 4 cases of primary disease recurrence (6%), 4 cases of infection (6%) and others. Complications after renal biopsy included 15 cases of microscopic hematuria (21%), 1 case of gross hematuria with spontaneous cessation and 1 case of life threatening hemorrhage. Ultrasonography-guided renal biopsy is a safe and effective diagnostic method for the evaluation of renal dysfunction following renal transplantation.

  2. The renal effects and initial characterization of venom from Philodryas nattereri Steindachner, 1870

    Directory of Open Access Journals (Sweden)

    Marinetes Dantas de Aquino Nery

    2014-01-01

    Full Text Available The venom of the snake Philodryas nattereri is a mixture of proteins and toxic peptides with several important local and systemic actions, which are similar to those occurring in Bothrops snake bites. The mechanisms involved in the local and systemic actions of this venom are unknown. The aims of the work were to initial characterization of P. nattereri venom and investigate the effects of the poison in the renal perfusion system and in cultured renal tubular cells of the type MDCK (Madin–Darby canine kidney. The P. nattereri venom is composed majority of proteins (86.3% and this poison promoted changes in all the evaluated renal parameters, mainly decreasing renal perfusion pressure (PP and renal vascular resistance (RVR and increasing urine flow (UF and glomerular filtration rate (GFR. The most relevant result was that this venom was highly detrimental to the renal tubules independent of the PP reduction, which was shown by a decrease in sodium (Na+, potassium (K+ and chloride (Cl− electrolyte transport in the studied concentrations. The glomeruli and tubules contain protein bodies and blood extravasation, which were observed by histological analysis. The venom of P. nattereri reduced viability of the MDCK cells only at high concentrations (50 and 100 μg/mL with an IC50 of 169.5 μg/mL.

  3. A possible simplification for the estimation of area under the curve (AUC₀₋₁₂) of enteric-coated mycophenolate sodium in renal transplant patients receiving tacrolimus.

    Science.gov (United States)

    Fleming, Denise H; Mathew, Binu S; Prasanna, Samuel; Annapandian, Vellaichamy M; John, George T

    2011-04-01

    Enteric-coated mycophenolate sodium (EC-MPS) is widely used in renal transplantation. With a delayed absorption profile, it has not been possible to develop limited sampling strategies to estimate area under the curve (mycophenolic acid [MPA] AUC₀₋₁₂), which have limited time points and are completed in 2 hours. We developed and validated simplified strategies to estimate MPA AUC₀₋₁₂ in an Indian renal transplant population prescribed EC-MPS together with prednisolone and tacrolimus. Intensive pharmacokinetic sampling (17 samples each) was performed in 18 patients to measure MPA AUC₀₋₁₂. The profiles at 1 month were used to develop the simplified strategies and those at 5.5 months used for validation. We followed two approaches. In one, the AUC was calculated using the trapezoidal rule with fewer time points followed by an extrapolation. In the second approach, by stepwise multiple regression analysis, models with different time points were identified and linear regression analysis performed. Using the trapezoidal rule, two equations were developed with six time points and sampling to 6 or 8 hours (8hrAUC[₀₋₁₂exp]) after the EC-MPS dose. On validation, the 8hrAUC(₀₋₁₂exp) compared with total measured AUC₀₋₁₂ had a coefficient of correlation (r²) of 0.872 with a bias and precision (95% confidence interval) of 0.54% (-6.07-7.15) and 9.73% (5.37-14.09), respectively. Second, limited sampling strategies were developed with four, five, six, seven, and eight time points and completion within 2 hours, 4 hours, 6 hours, and 8 hours after the EC-MPS dose. On validation, six, seven, and eight time point equations, all with sampling to 8 hours, had an acceptable r with the total measured MPA AUC₀₋₁₂ (0.817-0.927). In the six, seven, and eight time points, the bias (95% confidence interval) was 3.00% (-4.59 to 10.59), 0.29% (-5.4 to 5.97), and -0.72% (-5.34 to 3.89) and the precision (95% confidence interval) was 10

  4. Tubular nanostructured materials for bioapplications

    Science.gov (United States)

    Xie, Jining; Chen, Linfeng; Srivatsan, Malathi; Varadan, Vijay K.

    2009-03-01

    Tubular nanomaterials possess hollow structures as well as high aspect ratios. In addition to their unique physical and chemical properties induced by their nanoscale dimensions, their inner voids and outer surfaces make them ideal candidates for a number of biomedical applications. In this work, three types of tubular nanomaterials including carbon nanotubes, hematite nanotubes, and maghemite nanotubes, were synthesized by different chemical techniques. Their structural and crystalline properties were characterized. For potential bioapplications of tubular nanomaterials, experimental investigations were carried out to demonstrate the feasibility of using carbon nanotubes, hematite nanotubes, and maghemite nanotubes in glucose sensing, neuronal growth, and drug delivery, respectively. Preliminary results show the promise of tubular nanomaterials in future biomedical applications.

  5. Elevated N-terminal pro-brain natriuretic peptide levels predict an enhanced anti-hypertensive and anti-proteinuric benefit of dietary sodium restriction and diuretics, but not angiotensin receptor blockade, in proteinuric renal patients.

    Science.gov (United States)

    Slagman, Maartje C J; Waanders, Femke; Vogt, Liffert; Damman, Kevin; Hemmelder, Marc; Navis, Gerjan; Laverman, Gozewijn D

    2012-03-01

    Renin-angiotensin aldosterone system (RAAS) blockade only partly reduces blood pressure, proteinuria and renal and cardiovascular risk in chronic kidney disease (CKD) but often requires sodium targeting [i.e. low sodium diet (LS) and/or diuretics] for optimal efficacy. However, both under- and overtitration of sodium targeting can easily occur. We evaluated whether N-terminal pro-brain natriuretic peptide (NT-proBNP), a biomarker of volume expansion, predicts the benefits of sodium targeting in CKD patients. In a cross-over randomized controlled trial, 33 non-diabetic CKD patients (proteinuria 3.8 ± 0.4 g/24 h, blood pressure 143/86 ± 3/2 mmHg, creatinine clearance 89 ± 5 mL/min) were treated during 6-week periods with placebo, angiotensin receptor blockade (ARB; losartan 100 mg/day) and ARB plus diuretics (losartan 100 mg/day plus hydrochlorothiazide 25 mg/day), combined with LS (93 ± 52 mmol Na(+)/24 h) and regular sodium diet (RS; 193 ± 62 mmol Na(+)/24 h, P diuretics and was normalized by ARB + diuretic + LS [39 (26-59) pg/mL, P = 0.65 versus controls]. NT-proBNP levels above the upper limit of normal (>125 pg/mL) predicted a larger reduction of blood pressure and proteinuria by LS and diuretics but not by ARB, during all steps of the titration regimen. Elevated NT-proBNP levels predict an enhanced anti-hypertensive and anti-proteinuric benefit of sodium targeting, but not RAAS blockade, in proteinuric CKD patients. Importantly, this applies to the untreated condition, as well as to the subsequent treatment steps, consisting of RAAS blockade and even RAAS blockade combined with diuretics. NT-proBNP can be a useful tool to identify CKD patients in whom sodium targeting can improve blood pressure and proteinuria.

  6. Hereditary Hypokalemic salt-losing tubular disorders

    International Nuclear Information System (INIS)

    Peters, M.; Konard, M.; Seyberth, H.W.

    2003-01-01

    The inherited hypokalemic tubular disorders are frequently summarized under the heading Bartter Syndrome since they share several clinical and biochemical findings such as renal salt wasting, hypokalemic metabolic alkalosis, normal blood pressure despite hypereninemic hyperaldosteronism and hyperplasia of the juxtaglomerular apparatus. However, careful characterization of the clinical phenotype and correlation with the clinical phenotype and the correlation with the underlying molecular basis justifies the differentiation into at least four distinct disease entities: (i) the hyperprostaglandin E syndrome or antenatal variant of Bartter syndrome (HPS/aBS), which is caused by mutations in either the Na-K-2Cl cotransporter or the potassium channel of the medullary thick ascending limb of Henle's loop; (ii) the HPS/aBS with sensorineural deafness which results from inactivating mutation in the Barttin beta-subunit of the renal chloride channels; (iii) the classic Bartter syndrome caused by mutations in the chloride channel of the distal nephron; and (iv)Gitelman's variant of Bartter syndrome which is caused by mutations of the Na-Cl cotransporter of the distal convoluted tubule. This review will summarize the clinical characteristics of these diseases and progress recently made in the identification of the underlying molecular defects that will hopefully add to the current knowledge of the pathogenesis of these diseases. (author)

  7. Nonclinical safety of the sodium-glucose cotransporter 2 inhibitor empagliflozin.

    Science.gov (United States)

    Bogdanffy, Matthew S; Stachlewitz, Robert F; van Tongeren, Susan; Knight, Brian; Sharp, Dale E; Ku, Warren; Hart, Susan Emeigh; Blanchard, Kerry

    2014-01-01

    Empagliflozin, a selective inhibitor of the renal tubular sodium-glucose cotransporter 2, was developed for treatment of type 2 diabetes mellitus. Nonclinical safety of empagliflozin was studied in a battery of tests to support global market authorization. Safety pharmacology studies indicated no effect of empagliflozin on measures of respiratory or central nervous system function in rats or cardiovascular safety in telemeterized dogs. In CD-1 mouse, Wistar Han rat, or beagle dogs up to 13, 26, or 52 weeks of treatment, respectively, empagliflozin exhibited a toxicity profile consistent with secondary supratherapeutic pharmacology related to glucose loss and included decreased body weight and body fat, increased food consumption, diarrhea, dehydration, decreased serum glucose and increases in other serum parameters reflective of increased protein catabolism, gluconeogenesis, and electrolyte imbalances, and urinary changes such as polyuria and glucosuria. Microscopic changes were consistently observed in kidney and included tubular nephropathy and interstitial nephritis (dog), renal mineralization (rat) and tubular epithelial cell karyomegaly, single cell necrosis, cystic hyperplasia, and hypertrophy (mouse). Empagliflozin was not genotoxic. Empagliflozin was not carcinogenic in female mice or female rats. Renal adenoma and carcinoma were induced in male mice only at exposures 45 times the maximum clinical dose. These tumors were associated with a spectrum of nonneoplastic changes suggestive of a nongenotoxic, cytotoxic, and cellular proliferation-driven mechanism. In male rats, testicular interstitial cell tumors and hemangiomas of the mesenteric lymph node were observed; both tumors are common in rats and are unlikely to be relevant to humans. These studies demonstrate the nonclinical safety of empagliflozin. © The Author(s) 2014.

  8. Is Sodium Bicarbonate Therapy Still Up To Date?

    Directory of Open Access Journals (Sweden)

    Hüseyin Kurt

    2015-12-01

    Full Text Available Sodium bicarbonate (SB, which has a vital role in the regulation of acid-base balance of all tissues and organs, is one of the most important buffering systems of the body. SB plays an important role in the treatment of poisoning caused by numerous agents including mainly salicylate and tricyclic antidepressants. In metabolic acidosis (MA occurred in patient with systemic and metabolic diseases, first, the primary disease should be treated and in the case of low bicarbonate levels such as diarrhea and renal tubular acidosis, missing SB should be recovered. As the kidney has an important role in acid-base balance, SB is widely used in the treatment of acute and chronic renal failure. Although there is no conclusive evidence to prevent contrast nephropathy, SB comes to the fore compared to other agents. SB is used due to MA and its effects occurring in acute renal failure. In addition, SB treatment applied to reduce the increased acid levels in chronic kidney failure may reduce mortality. While SB can be used as individualized in lactic acidosis and cardiac arrest cases, it can be used safely as a performance enhancer for athletes. SB is used widely in gastrointestinal tract diseases due to its antacid effects and its routine use is not recommended in diabetic ketoacidosis. These data demonstrate that SB is still popular and it will retain its popularity in the near future.

  9. Renal manifestations in children with Alagille syndrome.

    Science.gov (United States)

    Di Pinto, Diana; Adragna, Marta

    2018-04-01

    Alagille syndrome (AS) is a cholestatic disease secondary to scarcity of interlobular bile ducts. It is associated with extrahepatic manifestations, and renal involvement is frequent. To describe the prevalence, type and outcome of renal pathology in children with AS. The presence and outcome of renal pathology was retrospectively studied in 21 children who met AS criteria. Renal pathology was observed in 18 patients (85.7%): (1) ultrasound variations in 7 patients (6 cases of bilateral renal dysplasia and 1 case of renal agenesis); (2) distal renal tubular acidosis in 2 patients; (3) a drop in glomerular filtration and/or proteinuria in 16 patients. The frequency of a drop in glomerular filtration was similar between patients with and without pathological kidney ultrasound findings. Our study confirms a high prevalence of renal involvement, which enhances the importance of diagnosis and renal function follow-up in children with AS. Sociedad Argentina de Pediatría.

  10. The renal concentrating mechanism and the clinical consequences of its loss

    Science.gov (United States)

    Agaba, Emmanuel I.; Rohrscheib, Mark; Tzamaloukas, Antonios H.

    2012-01-01

    The integrity of the renal concentrating mechanism is maintained by the anatomical and functional arrangements of the renal transport mechanisms for solute (sodium, potassium, urea, etc) and water and by the function of the regulatory hormone for renal concentration, vasopressin. The discovery of aquaporins (water channels) in the cell membranes of the renal tubular epithelial cells has elucidated the mechanisms of renal actions of vasopressin. Loss of the concentrating mechanism results in uncontrolled polyuria with low urine osmolality and, if the patient is unable to consume (appropriately) large volumes of water, hypernatremia with dire neurological consequences. Loss of concentrating mechanism can be the consequence of defective secretion of vasopressin from the posterior pituitary gland (congenital or acquired central diabetes insipidus) or poor response of the target organ to vasopressin (congenital or nephrogenic diabetes insipidus). The differentiation between the three major states producing polyuria with low urine osmolality (central diabetes insipidus, nephrogenic diabetes insipidus and primary polydipsia) is done by a standardized water deprivation test. Proper diagnosis is essential for the management, which differs between these three conditions. PMID:23293407

  11. The Protective Role of Tempol Against Oxidative Stress-Related Renal Impairment Induced by Gamma Rays in Rats

    International Nuclear Information System (INIS)

    Mekawy, H.M.S.; Elkhouly, W.A.; Tawfik, S.S.

    2015-01-01

    Tempol (4-hydroxy-2,2,6,6-tetramethyl-piperidine-1 oxyl) is a naturally occurring substance that counteracts the harmful and damaging effects of oxidation in animal tissues and has been reported to permeate the biological membranes. In this study, tempol with dose of 18 mg/kg/day for 2 weeks has been shown to be effective in preventing several of the adverse consequences of oxidative stress and inflammation that underlie radiation damage. Adult rats were exposed to a total dose of 6 Gy gamma rays to determine the protective role of tempol on the biochemistry of the injured kidney because gamma rays displayed significant augmentation in renal oxidative modifications markers.The results indicated that plasma renal function tests; urea (Ur), creatinine (Cr), uric acid (UA) and sodium (Na), and plasma renal tubular injury markers; γ -glutamyltransferase ( γ -GT), aspartate aminotransferase (AST), creatine phosphokinase (CPK) and lactate dehydrogenase (LDH), were increased significantly in gamma rays group. In addition, the renal oxidative stress parameters; malondialdehyde (MDA), total cholesterol (TC) and protein carbonyl (PC), were increased significantly, and reduced glutathione (GSH) was decreased significantly in gamma rays group. Moreover, the levels of renal antioxidant enzymes; superoxide dismutase (SOD) and catalase (CAT), were decreased significantly, and myeloperoxidase (MPO) was in creased significantly in gamma rays group.The antioxidant treatment with tempol ameliorates gamma rays-induced biochemical alterations and dysfunction of kidney.Tempol, at levels within tolerable nutritional strategy, reduced the oxidative modification-related renal impairment induced by gamma radiation in rats.

  12. Early segmental changes in ischemic acute tubular necrosis of the rat kidney

    DEFF Research Database (Denmark)

    Faarup, Poul; Nørgaard, Tove; Hegedüs, Viktor

    2004-01-01

    The background and mechanisms of ischemic acute tubular necrosis are still essentially unclarified. Therefore a quantitative morphological technique was applied for evaluation of the early structural changes in different fractions of the proximal convoluted tubule in the rat renal cortex. In male...

  13. HISTOSPECTROPHOTOMETRICAL AND IMMUNOHISTOCHEMISTRICAL RESEARCH OF RENAL INTRATUBULAR NEOPLASIA IN PERITUMOUROUS ZONE OF A RENAL CARCINOMA

    Directory of Open Access Journals (Sweden)

    T. M. Cherdantseva

    2012-01-01

    Full Text Available In this work displays renal intratubular neoplasia (RIN in peritumourous zone of a renal carcinoma have been studied. The object of our work, are the operative materials of 42 patients. Middle age of patients has made 57,4 ± 1,4 year. Men was 25, women — 17. Characteristic of tubular epithelium in PZ a renal carcinoma have been studied morphofunctional by means of histological, histospectrophotometrical and immunohistochemistrical methods. It is shown, that in PZ tumors of a high degree displays, of RIN much more often, than in tumors of low degree anaplasia. In tumors of a high degree anaplasia in tubular epithelium PZ registered increasing of nucleus, ploidy and expression of AgNORs, Ki-67, p53 and bcl-2. The presence of displays RIN in tubular epithelium PZ at a renal carcinoma should be considered at surgery operations.

  14. HISTOSPECTROPHOTOMETRICAL AND IMMUNOHISTOCHEMISTRICAL RESEARCH OF RENAL INTRATUBULAR NEOPLASIA IN PERITUMOUROUS ZONE OF A RENAL CARCINOMA

    Directory of Open Access Journals (Sweden)

    T. M. Cherdantseva

    2014-08-01

    Full Text Available In this work displays renal intratubular neoplasia (RIN in peritumourous zone of a renal carcinoma have been studied. The object of our work, are the operative materials of 42 patients. Middle age of patients has made 57,4 ± 1,4 year. Men was 25, women — 17. Characteristic of tubular epithelium in PZ a renal carcinoma have been studied morphofunctional by means of histological, histospectrophotometrical and immunohistochemistrical methods. It is shown, that in PZ tumors of a high degree displays, of RIN much more often, than in tumors of low degree anaplasia. In tumors of a high degree anaplasia in tubular epithelium PZ registered increasing of nucleus, ploidy and expression of AgNORs, Ki-67, p53 and bcl-2. The presence of displays RIN in tubular epithelium PZ at a renal carcinoma should be considered at surgery operations.

  15. Renal rickets-practical approach

    Science.gov (United States)

    Sahay, Manisha; Sahay, Rakesh

    2013-01-01

    Rickets/osteomalacia is an important problem in a tropical country. Many cases are due to poor vitamin D intake or calcium deficient diets and can be corrected by administration of calcium and vitamin D. However, some cases are refractory to vitamin D therapy and are related to renal defects. These include rickets of renal tubular acidosis (RTA), hypophosphatemic rickets, and vitamin D dependent rickets (VDDR). The latter is due to impaired action of 1α-hydroxylase in renal tubule. These varieties need proper diagnosis and specific treatment. PMID:24251212

  16. Short-Term Effects of Ankaferd Hemostat for Renal Artery Embolization: An Experimental Study

    International Nuclear Information System (INIS)

    Ozbek, Orhan; Acar, Kadir; Koc, Osman; Saritas, Kadir; Toy, Hatice; Solak, Yalcin; Ozbek, Seda; Kucukapan, Ahmet; Guler, Ibrahim; Gaipov, Abduzhappar; Turk, Suleyman; Haznedaroglu, Ibrahim Celaleddin

    2013-01-01

    Renal artery embolization (RAE) is a minimally invasive therapeutic technique that is utilized in a number of disorders. Ankaferd is a novel hemostatic agent with a new mechanism of action independent of clotting factors. We used Ankaferd for RAE in a sheep model. Seven adult female sheep were included in the study. Selective renal arteriogram using 5-F diagnostic catheter was performed to make sure that each kidney was fed by a single renal artery and the animal had normal renal vasculature. Coaxial 2.7-F microcatheter was advanced to the distal main renal artery. Under fluoroscopic guidance, 2 mL of Ankaferd mixed with 2 mL of nonionic iodinated contrast agent was slowly injected. Fluoroscopy was used to observe the deceleration of flow and stagnation. Control renal angiograms were performed just after embolization. After the procedure, the animals were observed for 1 day and then sacrificed with intravenous sodium thiopental. The technical success was observed in seven of the seven animals.. After embolization procedure, none of the animals died or experienced a major systemic adverse event. On macroscopic examination of the embolized kidneys, thrombus at the level of main renal artery formed after Ankaferd embolization was more compact compared with the thrombi that was not Ankaferd-associated, which was observed elsewhere. Microscopically, majority of the renal tubular cells (80–90 %) were necrotic, and there was epithelial cell damage in a small portion of the cells (10–20 %). RAE was safe and effective in the short-term with Ankaferd in studied animals. Further studies should be conducted to better delineate the embolizing potential of this novel hemostatic agent.

  17. Short-Term Effects of Ankaferd Hemostat for Renal Artery Embolization: An Experimental Study

    Energy Technology Data Exchange (ETDEWEB)

    Ozbek, Orhan, E-mail: orhan.ozbek@gmail.com [Selcuk University, Department of Radiology, Meram School of Medicine (Turkey); Acar, Kadir [Selcuk University, Division of Hematology, Department of Internal Medicine, Meram School of Medicine (Turkey); Koc, Osman [Selcuk University, Department of Radiology, Meram School of Medicine (Turkey); Saritas, Kadir [Afyon Kocatepe University, Department of General Surgery, Veterinary Faculty (Turkey); Toy, Hatice [Selcuk University, Department of Pathology, Meram School of Medicine (Turkey); Solak, Yalcin [Selcuk University, Division of Nephrology, Department of Internal Medicine, Meram School of Medicine (Turkey); Ozbek, Seda [Selcuk University, Department of Radiology, Selcuklu School of Medicine (Turkey); Kucukapan, Ahmet; Guler, Ibrahim [Selcuk University, Department of Radiology, Meram School of Medicine (Turkey); Gaipov, Abduzhappar; Turk, Suleyman [Selcuk University, Division of Nephrology, Department of Internal Medicine, Meram School of Medicine (Turkey); Haznedaroglu, Ibrahim Celaleddin [Hacettepe University, Division of Hematology, Department of Internal Medicine, Faculty of Medicine (Turkey)

    2013-04-15

    Renal artery embolization (RAE) is a minimally invasive therapeutic technique that is utilized in a number of disorders. Ankaferd is a novel hemostatic agent with a new mechanism of action independent of clotting factors. We used Ankaferd for RAE in a sheep model. Seven adult female sheep were included in the study. Selective renal arteriogram using 5-F diagnostic catheter was performed to make sure that each kidney was fed by a single renal artery and the animal had normal renal vasculature. Coaxial 2.7-F microcatheter was advanced to the distal main renal artery. Under fluoroscopic guidance, 2 mL of Ankaferd mixed with 2 mL of nonionic iodinated contrast agent was slowly injected. Fluoroscopy was used to observe the deceleration of flow and stagnation. Control renal angiograms were performed just after embolization. After the procedure, the animals were observed for 1 day and then sacrificed with intravenous sodium thiopental. The technical success was observed in seven of the seven animals.. After embolization procedure, none of the animals died or experienced a major systemic adverse event. On macroscopic examination of the embolized kidneys, thrombus at the level of main renal artery formed after Ankaferd embolization was more compact compared with the thrombi that was not Ankaferd-associated, which was observed elsewhere. Microscopically, majority of the renal tubular cells (80-90 %) were necrotic, and there was epithelial cell damage in a small portion of the cells (10-20 %). RAE was safe and effective in the short-term with Ankaferd in studied animals. Further studies should be conducted to better delineate the embolizing potential of this novel hemostatic agent.

  18. Renal imaging in paediatrics

    International Nuclear Information System (INIS)

    Porn, U.; Hahn, K.; Fischer, S.

    2003-01-01

    The most frequent renal diseases in paediatrics include urinary tract infections, hydronephrosis, kidney anomalies and reflux. The main reason for performing DMSA scintigraphy in paediatrics is the detection of cortical abnormalities related to urinary tract infection. Because the amount of tracer retained in the tubular cells is associated with the distribution of functioning renal parenchyma in the kidney, it is possible, to evaluate the split renal function. In comparison to ultrasound and intravenous urography the sensitivity in the detection of acute as well as chronic inflammatory changes is very high, however less specific. An indication for a renography in neonates and children is beside an estimation of the total renal function and the calculation of the split renal function, the assessment of renal drainage in patients with unclear dilatation of the collecting system in ultrasound. The analysis of the time activity curve provides, especially for follow-up studies, a reproducible method to assess the urinary outflow. The diuretic scintigraphy allows the detection of urinary obstruction. Subsequently it is possible to image the micturition phase to detect vesico-ureteric reflux (indirect MCU) after drainage of tracer from the renal pelvis. An reflux in the ureters or the pelvicalyceal system is visible on the scintigraphic images and can be confirmed by time activity curves. A more invasive technique is the direct isotope cystography with bladder catheterization. The present paper should give an overview about the role of nuclear medicine in paediatric urology. (orig.) [de

  19. Renal function study using I-123-OIH

    International Nuclear Information System (INIS)

    Yamashita, Masato; Osaka, Yosio; Aikawa, Ichiro

    1989-01-01

    Twenty-eight renal function studies were performed in 24 patients with renal diseases with I-123 orthoiodohippurate (I-123 OIH). Neither side effects nor abnormal laboratory values were attributable to I-123 OIH. Imaging with Tc-99m diethylene triaminepentaacetic acid (DTPA) was also performed in 20 patients within one week after I-123 imaging. Findings with I-123 OIH and Tc-99m DTPA were similar in all except for two patients. The two patients had received cadaveric renal transplantation. One patient presented with acute tubular necrosis and the other with chronic renal rejection. In these patients, I-123 imaging showed vascular stricture and Tc-99m imaging showed a decreased glomerular function. Because I-123 OIH and Tc-99m DTPA had different pharmacodynamics, combined use of the two imaging agents may be useful in evaluating renal rejection or acute tubular necrosis. (N.K.)

  20. Digitalis-like activity in human plasma: Relation to blood pressure and sodium balance

    Energy Technology Data Exchange (ETDEWEB)

    Goto, A.; Yamada, K.; Ishii, M.; Sugimoto, T. (Univ. of Tokyo (Japan))

    1990-10-01

    PURPOSE: On the assumption that renal tubular cells are more important as the target cells for a natriuretic factor than blood cells, we used a well-characterized cultured renal tubular cell line, Madin-Darby canine kidney (MDCK), cells to monitor the circulating digitalis-like factor in human plasma and examine its role in the regulation of blood pressure and sodium balance. SUBJECTS AND METHODS: We investigated the effects of plasma on binding of radioactive ouabain to monolayered MDCK cells in order to determine the level of a circulating digitalis-like factor. First, we measured specific 3H-ouabain binding to MDCK cells in the presence of plasma from 71 outpatients (34 normotensive subjects and 37 hypertensive patients) after incubation for 4 hours. Second, we measured specific 3H-ouabain binding after incubation of cells with plasma from 16 hospitalized subjects (eight normotensive subjects and eight hypertensive patients) receiving low and high sodium diets. RESULTS: In Study 1, ouabain binding was lower by 30% with plasma from hypertensive patients than with plasma from normotensive subjects (p less than 0.01). There was a significant negative correlation between individual subject's systolic or mean blood pressure and ouabain binding (r = -0.34, p less than 0.01 or r = -0.29, p less than 0.01). In Study 2, ouabain binding was also significantly reduced by 25% in the presence of plasma from hypertensive subjects as compared with plasma from normotensive subjects irrespective of sodium intake (p less than 0.01). A significant negative correlation was also found for all subjects between either systolic, diastolic, or mean blood pressure and ouabain binding (r = -0.58, p less than 0.01, r = -0.51, p less than 0.01, or r = -0.55, p less than 0.01, respectively).

  1. Hyponatremic hypertensive syndrome secondary to renal ischemia – Case report

    Directory of Open Access Journals (Sweden)

    Joana Cunha Oliveira

    2018-01-01

    Full Text Available Hyponatremic hypertensive syndrome (HHS is characterized by hypertensive crisis, and hyponatremia secondary to unilateral renal damage with glomerular and tubular dysfunction. Elevated plasma levels of renin in most cases suggest that the stimulation of renin release from the ischemic kidney plays an important pathophysiologic role. Activation of the renin-angiotensin system results in hypertension and causes secondary hyperfiltration, pressure diuresis and sodium loss from contralateral non-damaged kidney. An elevated renin level is a pathognomonic finding in HHS. Potassium deficiency from hyperaldosteronism may further stimulate renin secretion and intensify this vicious circle.We report a female term newborn, who presented with hypertensive crisis on the seventh day after traumatic birth. The first three days of life were uneventful. Initial treatment with captopril resulted in severe hypotension and hemodynamic instability. Lab work revealed hyponatremia, hypokalemia, and elevated peripheral renin activity and aldosterone levels. Complementary sonography and magnetic resonance confirmed right adrenal gland hematoma and several ischemic areas in the upper pole of the right kidney. The diagnosis of HHS secondary to renal ischemia was evoked.HHS is a rare condition in the neonatal period, though still under-recognized. In the neonatal and early infancy period, renovascular disease is the most common cause of secondary hypertension. In this case, there was no sign of vascular disease, the renin-angiotensin system was activated secondary to direct renal ischemia and infarction. The intense renin stimulation and pressure through the contralateral normal kidney results in high pressure natriuresis facilitating a severe volume-depleted state. Although the use of renin-angiotensin system inhibitors is the treatment of choice, it is imperative to re-establish hydration and renal perfusion before starting this antihypertensive medication. We aimed to

  2. Renal Alterations in Feline Immunodeficiency Virus (FIV-Infected Cats: A Natural Model of Lentivirus-Induced Renal Disease Changes

    Directory of Open Access Journals (Sweden)

    Mauro Pistello

    2012-08-01

    Full Text Available Human immunodeficiency virus (HIV is associated with several renal syndromes including acute and chronic renal failures, but the underlying pathogenic mechanisms are unclear. HIV and feline immunodeficiency virus (FIV share numerous biological and pathological features, including renal alterations. We investigated and compared the morphological changes of renal tissue of 51 experimentally and 21 naturally infected cats. Compared to the latter, the experimentally infected cats exhibited some mesangial widening and glomerulonephritis, milder proteinuria, and lower tubular and interstitial alterations. The numbers of giant protein tubular casts and tubular microcysts were also lower. In contrast, diffuse interstitial infiltrates and glomerular and interstitial amyloidosis were detected only in naturally infected cats. Similar alterations are found in HIV infected patients, thus supporting the idea of a causative role of FIV infection in renal disease, and underlining the relevance of the FIV and its natural host as an animal model for investigating lentivirus-associated nephropathy.

  3. Renal alterations in feline immunodeficiency virus (FIV)-infected cats: a natural model of lentivirus-induced renal disease changes.

    Science.gov (United States)

    Poli, Alessandro; Tozon, Natasa; Guidi, Grazia; Pistello, Mauro

    2012-09-01

    Human immunodeficiency virus (HIV) is associated with several renal syndromes including acute and chronic renal failures, but the underlying pathogenic mechanisms are unclear. HIV and feline immunodeficiency virus (FIV) share numerous biological and pathological features, including renal alterations. We investigated and compared the morphological changes of renal tissue of 51 experimentally and 21 naturally infected cats. Compared to the latter, the experimentally infected cats exhibited some mesangial widening and glomerulonephritis, milder proteinuria, and lower tubular and interstitial alterations. The numbers of giant protein tubular casts and tubular microcysts were also lower. In contrast, diffuse interstitial infiltrates and glomerular and interstitial amyloidosis were detected only in naturally infected cats. Similar alterations are found in HIV infected patients, thus supporting the idea of a causative role of FIV infection in renal disease, and underlining the relevance of the FIV and its natural host as an animal model for investigating lentivirus-associated nephropathy.

  4. Acute renal failure after rifampicin

    Directory of Open Access Journals (Sweden)

    Adriana Weinberg

    1984-12-01

    Full Text Available A patient with miliary tuberculosis and a chronic urogenital focus is described, who had a borderline renal function at diagnosis and developed overt renal failure upon daily treatment with rifampin (RMP, isoniazid (INH and ethambutol (EMB. This is the first Brazilian report of BMP induced renal damage. A renal biopsy taken on the third day of oliguria showed recent tubular necrosis with acute interstitial inflammation and granuloma formation. The aspect of the granulomatous lesion hightly suggested drug etiology because of the lack of palisading, high incidence of neutrophils and absence of facid-fast bacilli. This is the first presentation of an acute granulomatous interstitial nephritis probably due to RMP. Furthermore the pathogenesis of the renal damage caused by tuberculosis and RMP are discussed.

  5. Isolation and characterization of a primary proximal tubular epithelial cell model from human kidney by CD10/CD13 double labeling.

    Directory of Open Access Journals (Sweden)

    Cynthia Van der Hauwaert

    Full Text Available Renal proximal tubular epithelial cells play a central role in renal physiology and are among the cell types most sensitive to ischemia and xenobiotic nephrotoxicity. In order to investigate the molecular and cellular mechanisms underlying the pathophysiology of kidney injuries, a stable and well-characterized primary culture model of proximal tubular cells is required. An existing model of proximal tubular cells is hampered by the cellular heterogeneity of kidney; a method based on cell sorting for specific markers must therefore be developed. In this study, we present a primary culture model based on the mechanical and enzymatic dissociation of healthy tissue obtained from nephrectomy specimens. Renal epithelial cells were sorted using co-labeling for CD10 and CD13, two renal proximal tubular epithelial markers, by flow cytometry. Their purity, phenotypic stability and functional properties were evaluated over several passages. Our results demonstrate that CD10/CD13 double-positive cells constitute a pure, functional and stable proximal tubular epithelial cell population that displays proximal tubule markers and epithelial characteristics over the long term, whereas cells positive for either CD10 or CD13 alone appear to be heterogeneous. In conclusion, this study describes a method for establishing a robust renal proximal tubular epithelial cell model suitable for further experimentation.

  6. An alternative hypothesis to the widely held view that renal excretion of sodium accounts for resistance to salt-induced hypertension

    Czech Academy of Sciences Publication Activity Database

    Kurtz, T. W.; DiCarlo, S. E.; Pravenec, Michal; Schmidlin, O.; Tanaka, M.; Morris Jr., R. C.

    2016-01-01

    Roč. 90, č. 5 (2016), s. 965-973 ISSN 0085-2538 Grant - others:AV ČR(CZ) AP1502 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985823 Keywords : blood pressure * hypertension * kidney * salt * salt-resistance * salt-sensitivity * sodium * sodium chloride Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 8.395, year: 2016

  7. Gremlin Activates the Smad Pathway Linked to Epithelial Mesenchymal Transdifferentiation in Cultured Tubular Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Raquel Rodrigues-Diez

    2014-01-01

    Full Text Available Gremlin is a developmental gene upregulated in human chronic kidney disease and in renal cells in response to transforming growth factor-β (TGF-β. Epithelial mesenchymal transition (EMT is one process involved in renal fibrosis. In tubular epithelial cells we have recently described that Gremlin induces EMT and acts as a downstream TGF-β mediator. Our aim was to investigate whether Gremlin participates in EMT by the regulation of the Smad pathway. Stimulation of human tubular epithelial cells (HK2 with Gremlin caused an early activation of the Smad signaling pathway (Smad 2/3 phosphorylation, nuclear translocation, and Smad-dependent gene transcription. The blockade of TGF-β, by a neutralizing antibody against active TGF-β, did not modify Gremlin-induced early Smad activation. These data show that Gremlin directly, by a TGF-β independent process, activates the Smad pathway. In tubular epithelial cells long-term incubation with Gremlin increased TGF-β production and caused a sustained Smad activation and a phenotype conversion into myofibroblasts-like cells. Smad 7 overexpression, which blocks Smad 2/3 activation, diminished EMT changes observed in Gremlin-transfected tubuloepithelial cells. TGF-β neutralization also diminished Gremlin-induced EMT changes. In conclusion, we propose that Gremlin could participate in renal fibrosis by inducing EMT in tubular epithelial cells through activation of Smad pathway and induction of TGF-β.

  8. Effect of cyclosporine therapy in transplanted patients-diagnostic values of tubular markers

    Directory of Open Access Journals (Sweden)

    Todor Gruev

    2003-09-01

    Full Text Available The introduction of cyclosporine A (CsA into the clinical practice has resulted in a major improvement in the short-term outcomes of solid organ transplantation and treatment of autoimune diseases. Chronic ScA nephrotoxicity has been described in kidneys of recepients of renal and other organ allografts. However, the exact mechanism underlying the development of fibrosis in chronic CsA nephrotoxicity has remained poorly understood. Evaluation with the validation data set showed that noninvasive urine protein differentiation might be a useful diagnostic strategy in nephrology. Over the past decade numerous studies in patients after transplantation have demonstrated that renal tubular cell injury after a toxic insult, results in sloughing of tubular debris and cell into the tubular lumen with eventual obstruction of tubular flow, increased intratubular pressure and backleak of glomerular filtrate out of the tubule. Urinary enzymes and low molecular proteins have been recommended as useful markers for the detection of changes in the kidney tissue in cases after renal transplantation. The aim of our study was to monitor the concentration and eventual nephrotoxic effect of Cyclosporine A using the concentration of low molecular proteins α-1-microglobulin and β−2-microglobulin, serum Cystatin C, as well as the concentration of isoform of GST-α and π.

  9. Effect of a keto acid-amino acid supplement on the metabolism and renal elimination of branched-chain amino acids in patients with chronic renal insufficiency on a low protein diet.

    Science.gov (United States)

    Teplan, V; Schück, O; Horácková, M; Skibová, J; Holecek, M

    2000-10-27

    The aim of our study was to evaluate the effect of a low-protein diet supplemented with keto acids-amino acids on renal function and urinary excretion of branched-chain amino acids (BCAA) in patients with chronic renal insufficiency (CRI). In a prospective investigation 28 patients with CRI (16 male, 12 female, aged 28-66 yrs, CCr 18.6 +/- 10.2 ml/min) on a low-protein diet (0.6 g of protein /kg BW/day and energy intake 140 kJ/kg BW/day) for a period of one month were included. Subsequently, this low protein diet was supplemented with keto acids-amino acids at a dose of 0.1 g/kg BW/day orally for a period of 3 months. Examinations performed at baseline and at the end of the follow-up period revealed significant increase in the serum levels of BCAA leucine (p Keto acid-amino acid administration had no effect on renal function and on the clearance of inulin, para-aminohippuric acid. Endogenous creatinine and urea clearance remained unaltered. A significant correlation between fractional excretion of sodium and leucine (p diet the supplementation of keto acids-amino acids does not affect renal hemodynamics, but is associated--despite increases in plasma concentrations--with a reduction of renal amino acid and protein excretion suggesting induction of alterations in the tubular transport mechanisms.

  10. Glomerular filtration and tubular secretion of MAG-3 in the rat kidney

    International Nuclear Information System (INIS)

    Mueller-Suur, R.M.; Mueller-Suur, C.

    1989-01-01

    Technetium-99m mercaptoacetyltriglycine (MAG-3) has recently been introduced as a new radiopharmaceutical for dynamic renal scintigraphy. To elucidate the mechanism of renal excretion, micropuncture experiments were performed in rat kidneys for direct measurements of glomerular filtration and tubular secretory capacity. Fluid of Bowman space was collected from superficial glomeruli and analyzed for its contents of [99mTc]MAG-3, [125I]hippurate and [3H]inulin during constant infusion of these compounds. The ratio of activity of ultrafiltrate to that of arterial plasma was 0.23 for MAG-3, 0.68 for hippurate and 1.04 for inulin which demonstrates that the filtrated amount of MAG-3 is only 23% of that of inulin, presumably because of higher plasma protein binding which was also measured in vitro and found to be 80 +/- 1.5% for MAG-3 and 32 +/- 2% for [125I]hippurate. Proximal and distal tubules were also micropunctured and their tubular fluid as well as the final urine analyzed for the activity of hippurate and MAG-3. The tubular fluid to plasma ratio values along the nephron and in the final urine were all lower for MAG-3 than for hippurate, indicating a lower secretory capacity. From measurements of whole renal clearance, GFR and plasma protein binding the filtered amount of MAG-3 was 0.26 and of hippurate 0.87 ml/min.g kidney weight (p less than 0.001) and the secreted amount 2.01 and 2.38 ml/min.g kidney weight (p less than 0.05), respectively. We conclude that MAG-3 is predominantly excreted by tubular secretion and that the lower renal clearance of MAG-3 as compared with that of hippurate is a result both of a substantially decreased glomerular filtration and of a lower tubular secretion

  11. [Surgical model of chronic renal failure: study in rabbits].

    Science.gov (United States)

    Costa, Andrei Ferreira Nicolau da; Pereira, Lara de Paula Miranda; Ferreira, Manoel Luiz; Silva, Paulo Cesar; Chagar, Vera Lucia Antunes; Schanaider, Alberto

    2009-02-01

    To establish a model of chronic renal failure in rabbits, with perspectives of its use for therapeutic and repairing actions. Nineteen males, adults rabbits (New Zealand) randomly distributed into three groups were used: Group 1 - Control (n =5); Group 2-Sham (n =7); and Group 3 - Experimental (n =7). They were anaesthetized by using intramuscular Cetamine, Diazepam and Fentanyl followed by Sevorane with vaporizer device. In Group 3, a bipolar left nephrectomy was carried out and after four weeks, it was also done a right nephrectomy. All the samples of the renal tissue were weighed. The Group 2 was only submitted to both abdominal laparotomies, without nephrectomy. Biochemical evaluations, with urea, creatinina, sodium and potassium measurement; abdominal ultrasound scan; scintigraphy and histological analysis were performed in all animals. In group 3 there was a progressive increase of urea (p=0.0001), creatinine (p=0.0001), sodium (p = 0,0002) and potassium (p=0,0003). The comparison of these results with those one of the Groups 1 and 2, in all intervals, revealed blood rising with statistical significant level (p < 0,05). In Group 3, the ultrasound scan identified an increasing of the left kidney size, after 16 weeks and at the 4th week the scintigraphy confirmed the loss of 75% of the left renal mass. In the same group, the histological evaluation showed subcapsular and intersticial fibrosis and also tubular regeneration. The experimental model of IRC is feasible, with animal's survival in middle term which allows the use of this interval like a therapeutic window for testing different approaches in order to repair the kidney damages.

  12. Rhabdomyolysis with acute tubular necrosis following occupational inhalation of thinners.

    Science.gov (United States)

    Ngajilo, D; Ehrlich, R

    2017-07-01

    Thinners are mixtures of organic solvents commonly containing toluene, xylene, acetone, hexane, benzene and methyl isobutyl ketone. This report describes a case of rhabdomyolysis with acute tubular necrosis and renal failure, most likely attributable to toluene, following occupational exposure to thinners while cleaning a steel water tank. These adverse health effects have previously been reported following acute poisoning or intentional inhalation by drug abusers, but rarely in the occupational setting. Poor working conditions, lack of health and safety training and delayed treatment contributed to the onset and severity of the patient's complications. This case emphasizes the need for strict control measures, including adequate ventilation, training on working in confined spaces, appropriate personal protective equipment and emergency rescue procedures in such settings. In addition, rhabdomyolysis, acute tubular necrosis and renal failure should be added to safety data material as possible complications of excessive inhalation of thinners. © The Author 2017. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Do sodium-glucose co-transporter-2 inhibitors prevent heart failure with a preserved ejection fraction by counterbalancing the effects of leptin? A novel hypothesis.

    Science.gov (United States)

    Packer, Milton

    2018-06-01

    Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce the risk of serious heart failure events in patients with type 2 diabetes, but little is known about mechanisms that might mediate this benefit. The most common heart failure phenotype in type 2 diabetes is obesity-related heart failure with a preserved ejection fraction (HFpEF). It has been hypothesized that the synthesis of leptin in this disorder leads to sodium retention and plasma volume expansion as well as to cardiac and renal inflammation and fibrosis. Interestingly, leptin-mediated neurohormonal activation appears to enhance the expression of SGLT2 in the renal tubules, and SGLT2 inhibitors exert natriuretic actions at multiple renal tubular sites in a manner that can oppose the sodium retention produced by leptin. In addition, SGLT2 inhibitors reduce the accumulation and inflammation of perivisceral adipose tissue, thus minimizing the secretion of leptin and its paracrine actions on the heart and kidneys to promote fibrosis. Such fibrosis probably contributes to the impairment of cardiac distensibility and glomerular function that characterizes obesity-related HFpEF. Ongoing clinical trials with SGLT2 inhibitors in heart failure are positioned to confirm or refute the hypothesis that these drugs may favourably influence the course of obesity-related HFpEF by their ability to attenuate the secretion and actions of leptin. © 2018 John Wiley & Sons Ltd.

  14. Clinical impact of nonosmotic sodium storage

    NARCIS (Netherlands)

    Olde Engberink, R.H.G.

    2017-01-01

    High sodium intake is associated with hypertension and increased cardiovascular and renal risk. In this thesis we assessed whether these negative effects of sodium can be neutralised by glycosaminoglycans in the endothelial surface layer (i.e. nonosmotic sodium storage). Also, we investigate the

  15. X-ray diffraction studies on merohedrally twinned Δ1-62NtNBCe1-A crystals of the sodium/bicarbonate cotransporter.

    Science.gov (United States)

    Gill, Harindarpal S; Dutcher, Lauren; Boron, Walter F; Patel, Samir; Guay-Woodford, Lisa M

    2013-07-01

    NBCe1-A membrane-embedded macromolecules that cotransport sodium and bicarbonate ions across the bilayer serve to maintain acid-base homeostasis throughout the body. Defects result in a number of renal and eye disorders, including type-II renal tubular acidosis and cataracts. Here, crystals of a human truncated mutant of the cytoplasmic N-terminal domain of NBCe1 (Δ1-62NtNBCe1-A) are reported that diffract X-rays to 2.4 Å resolution. The crystal symmetry of Δ1-62NtNBCe1-A is of space group P31 with pseudo-P3121 symmetry and it has a hemihedral twin fraction of 33.0%. The crystals may provide insight into the pathogenic processes observed in a subset of patients with truncating and point mutations in the gene encoding NBCe1.

  16. Quantitative renal cinescintigraphy with iodine-123 hippuran methodological aspects, kit for labeling of hippuran

    International Nuclear Information System (INIS)

    Mehdaoui, A.; Pecking, A.; Delorme, G.; Mathonnat, F.; Debaud, B.; Bardy, A.; Coornaert, S.; Merlin, L.; Vinot, J.M.; Desgrez, A.; Gambini, D.; Vernejoul, P. de.

    1981-08-01

    The development of an extemporaneous kit for the labeling of ortho-iodo-hippuric acid (Hippuran) with iodine 123 allows the performance of a routine quantitative renal cinescintigraphy providing in 20 minutes, and in an absolutely non-traumatic way, a very complete renal morphofunctional study including: a cortical renal scintigraphy, sequential scintigraphies of excretory tract, renal functional curves, tubular, global, and separate clearances for each kidney. This functional quantitative investigation method should take a preferential place in the routine renal balance. The methodology of the technique is explained and compared to classical methods for estimation of tubular, global and separate clearances [fr

  17. Inhibition of WISE preserves renal allograft function.

    Science.gov (United States)

    Qian, Xueming; Yuan, Xiaodong; Vonderfecht, Steven; Ge, Xupeng; Lee, Jae; Jurisch, Anke; Zhang, Li; You, Andrew; Fitzpatrick, Vincent D; Williams, Alexia; Valente, Eliane G; Pretorius, Jim; Stevens, Jennitte L; Tipton, Barbara; Winters, Aaron G; Graham, Kevin; Harriss, Lindsey; Baker, Daniel M; Damore, Michael; Salimi-Moosavi, Hossein; Gao, Yongming; Elkhal, Abdallah; Paszty, Chris; Simonet, W Scott; Richards, William G; Tullius, Stefan G

    2013-01-01

    Wnt-modulator in surface ectoderm (WISE) is a secreted modulator of Wnt signaling expressed in the adult kidney. Activation of Wnt signaling has been observed in renal transplants developing interstitial fibrosis and tubular atrophy; however, whether WISE contributes to chronic changes is not well understood. Here, we found moderate to high expression of WISE mRNA in a rat model of renal transplantation and in kidneys from normal rats. Treatment with a neutralizing antibody against WISE improved proteinuria and graft function, which correlated with higher levels of β-catenin protein in kidney allografts. In addition, treatment with the anti-WISE antibody reduced infiltration of CD68(+) macrophages and CD8(+) T cells, attenuated glomerular and interstitial injury, and decreased biomarkers of renal injury. This treatment reduced expression of genes involved in immune responses and in fibrogenic pathways. In summary, WISE contributes to renal dysfunction by promoting tubular atrophy and interstitial fibrosis.

  18. Mathematical modeling of methyl ester concentration distribution in a continuous membrane tubular reactor and comparison with conventional tubular reactor

    Science.gov (United States)

    Talaghat, M. R.; Jokar, S. M.; Modarres, E.

    2017-10-01

    The reduction of fossil fuel resources and environmental issues made researchers find alternative fuels include biodiesels. One of the most widely used methods for production of biodiesel on a commercial scale is transesterification method. In this work, the biodiesel production by a transesterification method was modeled. Sodium hydroxide was considered as a catalyst to produce biodiesel from canola oil and methanol in a continuous tubular ceramic membranes reactor. As the Biodiesel production reaction from triglycerides is an equilibrium reaction, the reaction rate constants depend on temperature and related linearly to catalyst concentration. By using the mass balance for a membrane tubular reactor and considering the variation of raw materials and products concentration with time, the set of governing equations were solved by numerical methods. The results clearly show the superiority of membrane reactor than conventional tubular reactors. Afterward, the influences of molar ratio of alcohol to oil, weight percentage of the catalyst, and residence time on the performance of biodiesel production reactor were investigated.

  19. Hydrogen sulfide inhibits high glucose-induced NADPH oxidase 4 expression and matrix increase by recruiting inducible nitric oxide synthase in kidney proximal tubular epithelial cells.

    Science.gov (United States)

    Lee, Hak Joo; Lee, Doug Yoon; Mariappan, Meenalakshmi M; Feliers, Denis; Ghosh-Choudhury, Goutam; Abboud, Hanna E; Gorin, Yves; Kasinath, Balakuntalam S

    2017-04-07

    High-glucose increases NADPH oxidase 4 (NOX4) expression, reactive oxygen species generation, and matrix protein synthesis by inhibiting AMP-activated protein kinase (AMPK) in renal cells. Because hydrogen sulfide (H 2 S) inhibits high glucose-induced matrix protein increase by activating AMPK in renal cells, we examined whether H 2 S inhibits high glucose-induced expression of NOX4 and matrix protein and whether H 2 S and NO pathways are integrated. High glucose increased NOX4 expression and activity at 24 h in renal proximal tubular epithelial cells, which was inhibited by sodium hydrosulfide (NaHS), a source of H 2 S. High glucose decreased AMPK phosphorylation and activity, which was restored by NaHS. Compound C, an AMPK inhibitor, prevented NaHS inhibition of high glucose-induced NOX4 expression. NaHS inhibition of high glucose-induced NOX4 expression was abrogated by N (ω)-nitro-l-arginine methyl ester, an inhibitor of NOS. NaHS unexpectedly augmented the expression of inducible NOS (iNOS) but not endothelial NOS. iNOS siRNA and 1400W, a selective iNOS inhibitor, abolished the ameliorative effects of NaHS on high glucose-induced NOX4 expression, reactive oxygen species generation, and, matrix laminin expression. Thus, H 2 S recruits iNOS to generate NO to inhibit high glucose-induced NOX4 expression, oxidative stress, and matrix protein accumulation in renal epithelial cells; the two gasotransmitters H 2 S and NO and their interaction may serve as therapeutic targets in diabetic kidney disease. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Hematopoietic stem cell mobilization therapy accelerates recovery of renal function independent of stem cell contribution

    NARCIS (Netherlands)

    Stokman, Geurt; Leemans, Jaklien C.; Claessen, Nike; Weening, Jan J.; Florquin, Sandrine

    2005-01-01

    Acute renal failure and tubular cell loss as a result of ischemia constitute major challenges in renal pathophysiology. Increasing evidence suggests important roles for bone marrow stem cells in the regeneration of renal tissue after injury. This study investigated whether the enhanced availability

  1. Angiographic appearances of rare renal tumours

    International Nuclear Information System (INIS)

    Schmidt, M.; Taenzer, V.

    1980-01-01

    Oncocytomas, called oxyphil proximal tubular adenomas in the Anglo Saxon literature, and benign hypernephromas are non-malignant, usually symptomless, rare tumours belonging to the renal adenomas. Oncocytomas have angiographic appearances sufficiently uniform to permit a tentative diagnosis. Histologically benign hypernephromas do not possess characteristic angiographic appearances and, in the presence of tumour in the renal vein or necrotic avascular areas, must be regarded as potentially malignant. (orig.) [de

  2. Autosomal recessive hypophosphataemic rickets with hypercalciuria is not caused by mutations in the type II renal sodium/phosphate cotransporter gene.

    NARCIS (Netherlands)

    Heuvel, L.P.W.J. van den; Koul, K. Op de; Knots, E.; Knoers, N.V.A.M.; Monnens, L.A.H.

    2001-01-01

    BACKGROUND: At present the genetic defect for autosomal recessive and autosomal dominant hypophosphataemic rickets with hypercalciuria (HHRH) is unknown. Type II sodium/phosphate cotransporter (NPT2) gene is a serious candidate for being the causative gene in either or both autosomal recessive and

  3. Species diversity regarding the presence of proximal tubular progenitor cells of the kidney

    Directory of Open Access Journals (Sweden)

    J. Hansson

    2016-02-01

    Full Text Available The cellular source for tubular regeneration following kidney injury is a matter of dispute, with reports suggesting a stem or progenitor cells as the regeneration source while linage tracing studies in mice seemingly favor the classical theory, where regeneration is performed by randomly surviving cells. We, and others have previously described a scattered cell population localized to the tubules of human kidney, which increases in number following injury. Here we have characterized the species distribution of these proximal tubular progenitor cells (PTPCs in kidney tissue from chimpanzee, pig, rat and mouse using a set of human PTPC markers. We detected PTPCs in chimpanzee and pig kidneys, but not in mouse tissue. Also, subjecting mice to the unilateral urethral obstruction model, caused clear signs of tubular injury, but failed to induce the PTPC phenotype in renal tubules.

  4. Acute tubular necrosis (ATN) presenting with an unusually prolonged period of marked polyuria heralded by an abrupt oliguric phase.

    Science.gov (United States)

    Ramoutar, Virin; Landa, Cristian; James, Leighton R

    2014-08-22

    A 50-year-old African-American man presented with acute tubular necrosis (ATN) secondary to hypotension from non-typhoid Salmonella gastroenteritis and bacteraemia. The oliguric phase lasted only 24 h followed by prolonged polyuria for 20 days, with urine output in excess of 16 L/day at maximum. As indexed in PubMed this is only the second published case of this nature since 1974, in which an abrupt oliguric phase of 24 h or less heralded prolonged polyuria in ATN. The diagnosis is challenging as fractional excretion of sodium early in the clinical course and rapid normalisation of serum creatinine with intravenous fluids (IVF) may point towards prerenal azotaemia resulting in a premature discharge from hospital. Patients with an abrupt oliguric phase may suffer a secondary renal insult from the profound fluid loss that is to follow and may need inpatient monitoring with supplemental IVF to prevent deleterious outcomes. 2014 BMJ Publishing Group Ltd.

  5. Effect of nephrotoxicants on renal membrane transport: In vitro studies

    International Nuclear Information System (INIS)

    Ansari, R.A.; Berndt, W.O.

    1990-01-01

    It is possible to study the effects of nephrotoxicants on membrane function free of other cellular influences. By the use of Percoll gradient centrifugation, highly purified preparations of right-side-out basolateral (BL) and brush border (BB) membrane vesicles can be obtained from rat (male, Sprague-Dawley) renal cortex. Membrane function can be monitored by evaluation of sodium driven transport: 14 C-p-aminohippurate (PAH) for BL and 14 C-glucose for BB. Transport was measured by the rapid filtration technique. Each vesicle preparation was preincubated with the nephrotoxicant for five minutes before initiation of transport. Control vesicles showed a prominant overshoot 1 to 2 minutes after start of transport. Mercuric ion (Hg) had no effect on transport by BB at concentrations as high as 10μM. Transport by BL was reduced significantly at Hg concentrations as low as 100 nM. Chromate (Cr) also reduced BL transport at 100 nM and had no effect on BB transport. Citrinin significantly reduced both BB and BL transport, but the sensitivity of the membrane preparations differed. These data are consistent with the hypothesis that some nephrotoxicants may act on either side of the renal tubular cell membrane

  6. Endothelial protein C receptor in renal tubular epithelial cells and ...

    African Journals Online (AJOL)

    Jane

    2011-07-20

    Jul 20, 2011 ... Some factors such as high glucose, tumor necrosis factor–α and interleukin-1β can impact on ... a direct link to the reduction of mRNA levels in endothelial ..... can it improve insulin resistance and lower blood sugar, but it can ...

  7. Modified tubularized incised plate urethroplasty

    Directory of Open Access Journals (Sweden)

    Shivaji Mane

    2013-01-01

    Full Text Available Aim: To share our experience of doing tubularized incised plate urethroplasty with modifications. Materials and Methods: This is a single surgeon personal series from 2004 to 2009. One hundred patients of distal hypospadias were subjected for Snodgrass urethroplasty with preputioplasty. The age range was 1 to 5 year with mean age of 2.7 years. Selection criteria were good urethral plate, without chordee and torsion needing complete degloving. Main technical modification from original Snodgrass procedure was spongioplasty, preputioplasty, and dorsal slit when inability to retract prepuce during surgery. Results: Average follow-up period is 23 months. Seven (7% patients developed fistula and one patient had complete preputial dehiscence. Phimosis developed in three (3% patients and required circumcision. Dorsal slit was required in seven patients. One patient developed meatal stenosis in postoperative period. All other patients are passing single urinary stream and have cosmesis that is acceptable. Conclusions: Modified tubularized incised plate urethroplasty with preputioplasty effectively gives cosmetically normal looking penis with low complications.

  8. Bilateral renal metastasis of 261-265huerthle cell thyroid cancer with discordant uptake between I-131 sodium iodide and F-18 FDG

    Energy Technology Data Exchange (ETDEWEB)

    Claimon, Apichaya; Suh, Min Seok; Cheon, Gi Jeong; Lee, Dong Soo; Chung, June Key [Dept. of Nuclear Medicine, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, E. Edmund [Dept. of Radiological Sciences, University of California, Irvine (United States)

    2017-09-15

    Renal metastasis of thyroid cancer is extremely rare. We report the case of a 62-year-old woman with Hürthle cell thyroid cancer (HCTC) with lungs, bones, and bilateral kidneys metastases. The renal metastatic lesions were clearly demonstrated by {sup 131}I whole body scan (WBS) with SPECT/CT. However, they exhibited false-negative results in {sup 18}F-FDG PET/CT, kidney ultrasonography, and contrast-enhanced CT scan. The findings imply that tumors have low glucose metabolism and are able to accumulate radioiodine, which is not commonly found in the relatively aggressive nature of HCTC. The patient received two sessions of 200 mCi {sup 131}I therapy within 6 months duration. There was complete treatment response as evaluated by the second post-therapeutic {sup 131}I SPECT/CT and serum thyroglobulin. To our knowledge, renal metastasis from HCTC with positive {sup 131}I but negative {sup 18}F-FDG uptake has not been reported in the literature. This case suggests that {sup 131}I SPECT/CT is useful for lesion localization and prediction of {sup 131}I therapy response.

  9. Characterization of connective tissue growth factor expression in primary cultures of human tubular epithelial cells: modulation by hypoxia

    NARCIS (Netherlands)

    Kroening, Sven; Neubauer, Emily; Wullich, Bernd; Aten, Jan; Goppelt-Struebe, Margarete

    2010-01-01

    Kroening S, Neubauer E, Wullich B, Aten J, Goppelt-Struebe M. Characterization of connective tissue growth factor expression in primary cultures of human tubular epithelial cells: modulation by hypoxia. Am J Physiol Renal Physiol 298:F796-F806, 2010. First published December 23, 2009;

  10. Tubular lining material for pipelines having bends

    Energy Technology Data Exchange (ETDEWEB)

    Moringa, A.; Sakaguchi, Y.; Hyodo, M.; Yagi, I.

    1987-03-24

    A tubular lining material for pipelines having bends or curved portions comprises a tubular textile jacket made of warps and wefts woven in a tubular form overlaid with a coating of a flexible synthetic resin. It is applicable onto the inner surface of a pipeline having bends or curved portions in such manner that the tubular lining material with a binder onto the inner surface thereof is inserted into the pipeline and allowed to advance within the pipeline, with or without the aid of a leading rope-like elongated element, while turning the tubular lining material inside out under fluid pressure. In this manner the tubular lining material is applied onto the inner surface of the pipeline with the binder being interposed between the pipeline and the tubular lining material. The lining material is characterized in that a part of all of the warps are comprised of an elastic yarn around which, over the full length thereof, a synthetic fiber yarn or yarns have been left-and/or right-handedly coiled. This tubular lining material is particularly suitable for lining a pipeline having an inner diameter of 25-200 mm and a plurality of bends, such as gas service pipelines or house pipelines, without occurrence of wrinkles in the lining material in a bend.

  11. Effect of tolvaptan on renal handling of water and sodium, GFR and central hemodynamics in autosomal dominant polycystic kidney disease during inhibition of the nitric oxide system

    DEFF Research Database (Denmark)

    Therwani, Safa; Malmberg, My Emma Sofie; Rosenbaek, Jeppe Bakkestroem

    2017-01-01

    -dependent mechanism. U-AQP2 was not changed by tolvaptan, presumeably due to a counteracting effect of elevated p-AVP. The reduced GFR during tolvaptan most likely is caused by the reduction in extracellular fluid volume and blood pressure. Trial registration: Clinical Trial no: NCT02527863. Registered 18 February...... received tolvaptan 60 mg or placebo in a randomized, placebo-controlled, double blind, crossover study. L-NMMA (L-NG-monomethyl-arginine) was given as a bolus followed by continuous infusion during 60 min. We measured: GFR, urine output (UO), free water clearance (CH2O), fractional excretion of sodium...... (FENa), urinary excretion of aquaporin-2 channels (u-AQP2) and epithelial sodium channels (u-ENaCγ), plasma concentrations of vasopressin (p-AVP), renin (PRC), angiotensinII (p-AngII), aldosterone (p-Aldo), and central blood pressure (cBP). Results: During tolvaptan with NO-inhibition, a more pronounced...

  12. Hyperactivation of Nrf2 in early tubular development induces nephrogenic diabetes insipidus

    Science.gov (United States)

    Suzuki, Takafumi; Seki, Shiori; Hiramoto, Keiichiro; Naganuma, Eriko; Kobayashi, Eri H.; Yamaoka, Ayaka; Baird, Liam; Takahashi, Nobuyuki; Sato, Hiroshi; Yamamoto, Masayuki

    2017-01-01

    NF-E2-related factor-2 (Nrf2) regulates cellular responses to oxidative and electrophilic stress. Loss of Keap1 increases Nrf2 protein levels, and Keap1-null mice die of oesophageal hyperkeratosis because of Nrf2 hyperactivation. Here we show that deletion of oesophageal Nrf2 in Keap1-null mice allows survival until adulthood, but the animals develop polyuria with low osmolality and bilateral hydronephrosis. This phenotype is caused by defects in water reabsorption that are the result of reduced aquaporin 2 levels in the kidney. Renal tubular deletion of Keap1 promotes nephrogenic diabetes insipidus features, confirming that Nrf2 activation in developing tubular cells causes a water reabsorption defect. These findings suggest that Nrf2 activity should be tightly controlled during development in order to maintain renal homeostasis. In addition, tissue-specific ablation of Nrf2 in Keap1-null mice might create useful animal models to uncover novel physiological functions of Nrf2. PMID:28233855

  13. Tubular inverse opal scaffolds for biomimetic vessels

    Science.gov (United States)

    Zhao, Ze; Wang, Jie; Lu, Jie; Yu, Yunru; Fu, Fanfan; Wang, Huan; Liu, Yuxiao; Zhao, Yuanjin; Gu, Zhongze

    2016-07-01

    There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially oriented elliptical pattern microstructures on their surfaces. It is demonstrated that these tailored tubular scaffolds can effectively make endothelial cells to form an integrated hollow tubular structure on their inner surface and induce smooth muscle cells to form a circumferential orientation on their outer surface. These features of our tubular scaffolds make them highly promising for the construction of biomimetic blood vessels.There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially

  14. Effects of hyperventilation and hypocapnic/normocapnic hypoxemia on renal function and lithium clearance in humans

    DEFF Research Database (Denmark)

    Christensen, H; Klausen, T; Fogh-Andersen, N

    1998-01-01

    Using the renal clearance of lithium as an index of proximal tubular outflow, this study tested the hypothesis that acute hypocapnic hypoxemia decreases proximal tubular reabsorption to the same extent as hypocapnic normoxemia (hyperventilation) and that this response is blunted during normocapnic...

  15. Risk factors and co-morbidities associated with changes in renal ...

    African Journals Online (AJOL)

    2018-04-12

    Apr 12, 2018 ... Our systematic scoping review has demonstrated a research gap in ART nephrotoxicity, particularly with TDF, as well as the long-term ..... Urine analysis is important to detect proximal renal tubular damage in patients on TDF ...

  16. Role of ATP-dependent K channels in the effects of erythropoietin in renal ischaemia injury

    Directory of Open Access Journals (Sweden)

    Tonguç Utku Yilmaz

    2015-01-01

    Interpretation & conclusions: Our results showed that the cell proliferative, cytoprotective and anti-apoptotic effects of EPO were associated with KATP channels in the renal tubular cell culture model under hypoxic/normal conditions.

  17. In vivo antibody-mediated modulation of aminopeptidase A in mouse proximal tubular epithelial cells.

    Science.gov (United States)

    Mentzel, S; Dijkman, H B; van Son, J P; Wetzels, J F; Assmann, K J

    1999-07-01

    Aminopeptidase A (APA) is one of the many renal hydrolases. In mouse kidney, APA is predominantly expressed on the brush borders and sparsely on the basolateral membranes of proximal tubular epithelial cells. However, when large amounts of monoclonal antibodies (MAbs) against APA were injected into mice, we observed strong binding of the MAbs to the basolateral membranes, whereas the MAbs bound only transiently to the brush borders of the proximal tubular epithelial cells. In parallel, APA itself disappeared from the brush borders by both endocytosis and shedding, whereas it was increasingly expressed on the basolateral sides. Using ultrastructural immunohistology, we found no evidence for transcellular transport of endocytosed APA to the basolateral side of the proximal tubular epithelial cells. The absence of transcellular transport was confirmed by experiments in which we used a low dose of the MAbs. Such a low dose did not result in binding of the MAbs to the brush borders and had no effect on the presence of APA in the brush borders of the proximal tubular epithelial cells. In these experiments we still could observe binding of the MAbs to the basolateral membranes in parallel with the local appearance of APA. In addition, treatment of mice with chlorpromazine, a calmodulin antagonist that interferes with cytoskeletal function, largely inhibited the MAb-induced modulation of APA. Our studies suggest that injection of MAbs to APA specifically interrupts the normal intracellular traffic of this enzyme in proximal tubular epithelial cells. This intracellular transport is dependent on the action of cytoskeletal proteins.

  18. 78 FR 14361 - U.S. Steel Tubular Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United...

    Science.gov (United States)

    2013-03-05

    ... Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United States Steel Corporation, Mckeesport, PA; Notice of Initiation of Investigation To Terminate Certification of Eligibility Pursuant to... Tubular Products, McKeesport Tubular Operations Division, Subsidiary of United States Steel Corporation...

  19. Nuclear medicine in acute and chronic renal failure

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, R.A.; Byun, K.J.

    1982-07-01

    The diagnostic value of renal scintiscans in patients with acute or chronic renal failure has not been emphasized other than for the estimation of renal size. /sup 131/I OIH, /sup 67/gallium, /sup 99m/TcDTPA, glucoheptonate and DMSA all may be valuable in a variety of specific settings. Acute renal failure due to acute tubular necrosis, hepatorenal syndrome, acute interstitial nephritis, cortical necrosis, renal artery embolism, or acute pyelonephritis may be recognized. Data useful in the diagnosis and management of the patient with obstructive or reflux nephropathy may be obtained. Radionuclide studies in patients with chronic renal failure may help make apparent such causes as renal artery stenosis, chronic pyelonephritis or lymphomatous kidney infiltration. Future correlation of scanning results with renal pathology promises to further expand nuclear medicine's utility in the noninvasive diagnosis of renal disease.

  20. Nuclear medicine in acute and chronic renal failure

    International Nuclear Information System (INIS)

    Sherman, R.A.; Byun, K.J.

    1982-01-01

    The diagnostic value of renal scintiscans in patients with acute or chronic renal failure has not been emphasized other than for the estimation of renal size. 131 I OIH, 67 gallium, /sup 99m/TcDTPA, glucoheptonate and DMSA all may be valuable in a variety of specific settings. Acute renal failure due to acute tubular necrosis, hepatorenal syndrome, acute interstitial nephritis, cortical necrosis, renal artery embolism, or acute pyelonephritis may be recognized. Data useful in the diagnosis and management of the patient with obstructive or reflux nephropathy may be obtained. Radionuclide studies in patients with chronic renal failure may help make apparent such causes as renal artery stenosis, chronic pyelonephritis or lymphomatous kidney infiltration. Future correlation of scanning results with renal pathology promises to further expand nuclear medicine's utility in the noninvasive diagnosis of renal disease

  1. An unusual renal manifestation of chronic HBV infection.

    Science.gov (United States)

    Aravindan, Ananthakrishnapuram; Yong, Jim; Killingsworth, Murray; Strasser, Simone; Suranyi, Michael

    2010-08-01

    Hepatitis B viral infection is usually a self-limiting disease in immunocompetent individuals. Chronic infection can be seen in up to 5% of infected patients. Renal manifestations of chronic HBV infection are usually glomerular. We describe here an uncommon presentation of a patient with chronic HBV infection with very high viral load and rapidly progressive renal failure. Renal biopsy showed features of tubulointerstitial nephritis and tubular epithelial inclusion bodies suggestive of HBV infection. Entecavir treatment slowed down the progression of his renal disease. Tubulointerstitial nephritis should be considered as a part of the differential diagnosis in patients with HBV infection. Early antiviral treatment may halt the progression of renal disease.

  2. Tangshen Formula Attenuates Diabetic Nephropathy by Promoting ABCA1-Mediated Renal Cholesterol Efflux in db/db Mice.

    Science.gov (United States)

    Liu, Peng; Peng, Liang; Zhang, Haojun; Tang, Patrick Ming-Kuen; Zhao, Tingting; Yan, Meihua; Zhao, Hailing; Huang, Xiaoru; Lan, Huiyao; Li, Ping

    2018-01-01

    The commonly prescribed Tangshen Formula (TSF) is a traditional Chinese formulation that has been shown to reduce plasma lipid metabolism and proteinuria and improve the estimated glomerular filtration rate (eGFR) in patients with diabetic kidney disease. This study investigated the underlying mechanism whereby TSF regulates renal lipid accumulation and ameliorates diabetic renal injuries in spontaneous diabetic db/db mice and in vitro in sodium palmitate (PA)-stimulated and Abca1-SiRNA-transfected mouse tubular epithelial cells (mTECs). The results revealed that TSF treatment significantly ameliorated the renal injuries by lowering urinary albumin excretion and improving renal tissue injuries in diabetic (db/db) mice. Interestingly, the treatment with TSF also resulted in decreased cholesterol levels in the renal tissues of db/db mice, which was associated with increased expression of the peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α), the Liver X receptors (LXR), and ATP-binding cassette subfamily A member 1 (ABCA1), suggesting that TSF might attenuate diabetic kidney injury via a mechanism associated with improving cholesterol efflux in the diabetic kidney. This was investigated in vitro in mTECs, and the results showed that TSF reduced the PA-stimulated cholesterol accumulation in mTECs. Mechanistically, the addition of TSF was capable of reversing PA-induced downregulation of PGC-1α, LXR, and ABCA1 expression and cholesterol accumulation in mTECs, suggesting that TSF might act the protection via the PGC-1α-LXR-ABCA1 pathway to improve the cholesterol efflux in the renal tissues of db/db mice. This was further confirmed by silencing ABCA1 to block the promotive effect of TSF on cholesterol efflux in vitro . In conclusion, TSF might ameliorate diabetic kidney injuries by promoting ABCA1-mediated renal cholesterol efflux.

  3. Upregulation of Interleukin-33 in obstructive renal injury

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wei-Yu, E-mail: wychen624@cgmh.org.tw [Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan (China); Chang, Ya-Jen [Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan (China); Su, Chia-Hao [Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan (China); Tsai, Tzu-Hsien [Division of Cardiology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan (China); Chen, Shang-Der [Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan (China); Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, Kaohsiung, Taiwan (China); Hsing, Chung-Hsi [Department of Anesthesiology, Chi-Mei Medical Center, Tainan, Taiwan (China); Yang, Jenq-Lin, E-mail: jyang@adm.cgmh.org.tw [Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan (China)

    2016-05-13

    Interstitial fibrosis and loss of parenchymal tubular cells are the common outcomes of progressive renal diseases. Pro-inflammatory cytokines have been known contributing to the damage of tubular cells and fibrosis responses after renal injury. Interleukin (IL)-33 is a tissue-derived nucleus alarmin that drives inflammatory responses. The regulation and function of IL-33 in renal injury, however, is not well understood. To investigate the involvement of cytokines in the pathogenesis of renal injury and fibrosis, we performed the mouse renal injury model induced by unilateral urinary obstruction (UUO) and analyze the differentially upregulated genes between the obstructed and the contralateral unobstructed kidneys using RNA sequencing (RNAseq). Our RNAseq data identified IL33 and its receptor ST2 were upregulated in the UUO kidney. Quantitative analysis confirmed that transcripts of IL33 and ST2 were upregulated in the obstructed kidneys. Immunofluorescent staining revealed that IL-33 was upregulated in Vimentin- and alpha-SMA-positive interstitial cells. By using genetically knockout mice, deletion of IL33 reduced UUO-induced renal fibrosis. Moreover, in combination with BrdU labeling technique, we observed that the numbers of proliferating tubular epithelial cells were increased in the UUO kidneys from IL33-or ST2-deficient mice compared to wild type mice. Collectively, our study demonstrated the upregulation of IL-33/ST2 signaling in the obstructed kidney may promote tubular cell injury and interstitial fibrosis. IL-33 may serve as a biomarker to detect renal injury and that IL-33/ST2 signaling may represent a novel target for treating renal diseases. -- Highlights: •Interleukin (IL)-33 was upregulated in obstructed kidneys. •Interstitial myofibroblasts expressed IL-33 after UUO-induced renal injury. •Deficiency of IL33 reduced interstitial fibrosis and promoted tubular cell proliferation.

  4. Mobilization and removing of cadmium from kidney by GMDTC utilizing renal glucose reabsorption pathway

    International Nuclear Information System (INIS)

    Tang, Xiaojiang; Zhu, Jinqiu; Zhong, Zhiyong; Luo, Minhui; Li, Guangxian; Gong, Zhihong; Zhang, Chenzi; Fei, Fan; Ruan, Xiaolin; Zhou, Jinlin; Liu, Gaofeng; Li, Guoding; Olson, James; Ren, Xuefeng

    2016-01-01

    Chronic exposure to cadmium compounds (Cd 2+ ) is one of the major public health problems facing humans in the 21st century. Cd 2+ in the human body accumulates primarily in the kidneys which leads to renal dysfunction and other adverse health effects. Efforts to find a safe and effective drug for removing Cd 2+ from the kidneys have largely failed. We developed and synthesized a new chemical, sodium (S)-2-(dithiocarboxylato((2S,3R,4R,5R)-2,3,4,5,6 pentahydroxyhexyl)amino)-4-(methylthio) butanoate (GMDTC). Here we report that GMDTC has a very low toxicity with an acute lethal dose (LD50) of more than 10,000 mg/kg or 5000 mg/kg body weight, respectively, via oral or intraperitoneal injection in mice and rats. In in vivo settings, up to 94% of Cd 2+ deposited in the kidneys of Cd 2+ -laden rabbits was removed and excreted via urine following a safe dose of GMDTC treatment for four weeks, and renal Cd 2+ level was reduced from 12.9 μg/g to 1.3 μg/g kidney weight. We observed similar results in the mouse and rat studies. Further, we demonstrated both in in vitro and in animal studies that the mechanism of transporting GMDTC and GMDTC-Cd complex into and out of renal tubular cells is likely assisted by two glucose transporters, sodium glucose cotransporter 2 (SGLT2) and glucose transporter 2 (GLUT2). Collectively, our study reports that GMDTC is safe and highly efficient in removing deposited Cd 2+ from kidneys assisted by renal glucose reabsorption system, suggesting that GMDTC may be the long-pursued agent used for preventive and therapeutic purposes for both acute and chronic Cd 2+ exposure.

  5. Mobilization and removing of cadmium from kidney by GMDTC utilizing renal glucose reabsorption pathway

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Xiaojiang, E-mail: river-t@126.com [Guangdong Medical Laboratory Animal Center (China); Zhu, Jinqiu [Department of Epidemiology and Environmental Health, The State University of New York, Buffalo, NY (United States); Zhong, Zhiyong; Luo, Minhui; Li, Guangxian [Guangdong Medical Laboratory Animal Center (China); Gong, Zhihong [Department of Epidemiology and Environmental Health, The State University of New York, Buffalo, NY (United States); Zhang, Chenzi; Fei, Fan [Guangdong Medical Laboratory Animal Center (China); Ruan, Xiaolin [Guangdong Poison Control Center (China); Zhou, Jinlin [Golden Health (Foshan) Technology Co., Ltd (China); Liu, Gaofeng [School of Chemistry and Chemical Engineering, Sun Yat-Sen University (China); Li, Guoding [Guangdong Medical Laboratory Animal Center (China); Olson, James [Department of Epidemiology and Environmental Health, The State University of New York, Buffalo, NY (United States); Department of Pharmacology and Toxicology, The State University of New York, Buffalo, NY (United States); Ren, Xuefeng, E-mail: xuefengr@buffalo.edu [Guangdong Medical Laboratory Animal Center (China); Department of Epidemiology and Environmental Health, The State University of New York, Buffalo, NY (United States); Department of Pharmacology and Toxicology, The State University of New York, Buffalo, NY (United States)

    2016-08-15

    Chronic exposure to cadmium compounds (Cd{sup 2+}) is one of the major public health problems facing humans in the 21st century. Cd{sup 2+} in the human body accumulates primarily in the kidneys which leads to renal dysfunction and other adverse health effects. Efforts to find a safe and effective drug for removing Cd{sup 2+} from the kidneys have largely failed. We developed and synthesized a new chemical, sodium (S)-2-(dithiocarboxylato((2S,3R,4R,5R)-2,3,4,5,6 pentahydroxyhexyl)amino)-4-(methylthio) butanoate (GMDTC). Here we report that GMDTC has a very low toxicity with an acute lethal dose (LD50) of more than 10,000 mg/kg or 5000 mg/kg body weight, respectively, via oral or intraperitoneal injection in mice and rats. In in vivo settings, up to 94% of Cd{sup 2+} deposited in the kidneys of Cd{sup 2+}-laden rabbits was removed and excreted via urine following a safe dose of GMDTC treatment for four weeks, and renal Cd{sup 2+} level was reduced from 12.9 μg/g to 1.3 μg/g kidney weight. We observed similar results in the mouse and rat studies. Further, we demonstrated both in in vitro and in animal studies that the mechanism of transporting GMDTC and GMDTC-Cd complex into and out of renal tubular cells is likely assisted by two glucose transporters, sodium glucose cotransporter 2 (SGLT2) and glucose transporter 2 (GLUT2). Collectively, our study reports that GMDTC is safe and highly efficient in removing deposited Cd{sup 2+} from kidneys assisted by renal glucose reabsorption system, suggesting that GMDTC may be the long-pursued agent used for preventive and therapeutic purposes for both acute and chronic Cd{sup 2+} exposure.

  6. [Sodium-glucose co-transporter-2 inhibitors: from the bark of apple trees and familial renal glycosuria to the treatment of type 2 diabetes mellitus].

    Science.gov (United States)

    Mauricio, Dídac

    2013-09-01

    The therapeutic armamentarium for the treatment of hyperglycemia in type 2 diabetes mellitus is still inadequate. We are currently witnessing the introduction of a new mode of hypoglycemic treatment through induction of glycosuria to decrease the availability of the metabolic substrate, i.e. glucose. Clinical trials have shown that sodium-glucose co-transporter-2 (SGLT2) inhibitors are as efficacious as other oral hypoglycemic drugs. This article discusses the basic features of this new treatment concept and the efficacy and safety of this new drug group. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  7. Magnetic resonance of the renal transplantation

    International Nuclear Information System (INIS)

    Cauquil, P.; Hiesse, C.; Say, C.; Verdier, J.P.; Cauquil, M.; Brunet, A.M.; Galindo, R.; Tessier, J.P.

    1989-01-01

    Renal transplantation is the treatment of choice for renal insufficiency. Progress of surgical techniques and immuno-suppression have lead to better results. One year graft survival rate are 80% in most series. In this article, the role of imaging in renal transplantation, is defined. In surgical complications (fluid collections, obstruction, vascular insufficiency) non invasive radiology and interventionnal radiologic procedures have a great impact. Despite the perspectives of duplex and magnetic resonance, sensibility and specificity are not yet specified in medical complications: rejection, acute tubular necrosis, infection, drug toxicity. Association of these lesions is frequent and complicate analysis of results. Finally, transplant biopsy is still necessary to confirm the diagnosis [fr

  8. Proliferative capacity of stem/progenitor-like cells in the kidney may associate with the outcome of patients with acute tubular necrosis.

    Science.gov (United States)

    Ye, Youxin; Wang, Bingyin; Jiang, Xinxin; Hu, Weiming; Feng, Jian; Li, Hua; Jin, Mei; Ying, Yingjuan; Wang, Wenjuan; Mao, Xiaoou; Jin, Kunlin

    2011-08-01

    Animal studies indicate that adult renal stem/progenitor cells can undergo rapid proliferation in response to renal injury, but whether the same is true in humans is largely unknown. To examine the profile of renal stem/progenitor cells responsible for acute tubular necrosis in human kidney, double and triple immunostaining was performed using proliferative marker and stem/progenitor protein markers on sections from 10 kidneys with acute tubular necrosis and 4 normal adult kidneys. The immunopositive cells were recorded using 2-photon confocal laser scanning microscopy. We found that dividing cells were present in the tubules of the cortex and medulla, as well as the glomerulus in normal human kidney. Proliferative cells in the parietal layer of Bowman capsule expressed CD133, and dividing cells in the tubules expressed immature cell protein markers paired box gene 2, vimentin, and nestin. After acute tubular necrosis, Ki67-positive cells in the cortex tubules significantly increased compared with normal adult kidney. These Ki67-positive cells expressed CD133 and paired box gene 2, but not the cell death marker, activated caspase-3. In addition, the number of dividing cells increased significantly in patients with acute tubular necrosis who subsequently recovered, compared with patients with acute tubular necrosis who consequently developed protracted acute tubular necrosis or died. Our data suggest that renal stem/progenitor cells may reside not only in the parietal layer of Bowman capsule but also in the cortex and medulla in normal human kidney, and the proliferative capacity of renal stem/progenitor cells after acute tubular necrosis may be an important determinant of a patient's outcome. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Risk Assessment Study of Fluoride Salts: Probability-Impact Matrix of Renal and Hepatic Toxicity Markers.

    Science.gov (United States)

    Usuda, Kan; Ueno, Takaaki; Ito, Yuichi; Dote, Tomotaro; Yokoyama, Hirotaka; Kono, Koichi; Tamaki, Junko

    2016-09-01

    The present risk assessment study of fluoride salts was conducted by oral administration of three different doses of sodium and potassium fluorides (NaF, KF) and zinc fluoride tetrahydrate (ZnF2 •4H2O) to male Wistar rats. The rats were divided into control and nine experimental groups, to which oral injections of 0.5 mL distilled water and 0.5 mL of fluoride solutions, respectively, were given. The dosage of fluoride compounds was adjusted to contain 2.1 mg (low-dose group, LG), 4.3 mg (mid-dose group, MG), and 5.4 mg fluoride per 200 g rat body weight (high-dose group, HG) corresponding to 5, 10, and 12.5 % of LD50 values for NaF. The 24-h urine volume, N-acetyl-β-D-glucosaminidase (NAG) and creatinine clearance (Ccr) were measured as markers of possible acute renal impact. The levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined in serum samples as markers of acute hepatic impact. The levels of serum and urinary fluoride were determined to evaluate fluoride bioavailability. The results reveal that higher doses of NaF, KF, and ZnF2 induced renal damage as indicated by higher urinary NAG (p fluoride is a potential, dose-dependent risk factor of renal tubular damage.

  10. Urinary excretion of furosemide in rats with HgCl sub 2 -induced acute renal damage

    Energy Technology Data Exchange (ETDEWEB)

    Fujimura, Akio; Sudoh, Toshiaki; Ohashi, Kyoichi; Ebihara, Akio (Jichi Medical School, Tochigi (Japan))

    1992-01-01

    To examine the influence of mercuric chloride (HgCl{sub 2})-induced acute renal damage on urinary excretion of furosemide, HgCl{sub 2} or its vehicle along was given intraperitoneally to Wistar rats. The following two experiments were done. Study 1: three percent body weight (b.w.) of 1% NaCl solution or furosemide in 3% b.w. of 1% NaCl solution was given orally before and after HgCl{sub 2} treatment, and an 8-hour urine was collected. Study 2: furosemide was given orally, and blood samples were obtained at 1, 2, 3, 4, 6 and 8 hours after administration. Urinary excretion of N-acetyl-{beta}-D-glucosaminidase increased, and urine volume and urinary excretions of furosemide and sodium decreased in the HgCl{sub 2}-treated rats. There were significant correlations between the urinary furosemide and its diuretic effects. Regression lines after HgCl{sub 2} were significantly different from those before treatment. The values of absorption as well as elimination rate constant were smaller, while the time to maximum concentration and the elimination half-life were longer in the HgCl{sub 2}-treated rats compared to vehicle-treated animals. These results suggest that the urinary excretion of furosemide and the responsiveness of renal tubular cells to this agent are impaired in rats with HgCl{sub 2}-induced acute renal damage.

  11. Tubular bioreactor and its application; Tubular bioreactor to sono tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Endo, I.; Nagamune, T. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering; Yuki, K. [Nikka Whisky Distilling Co. Ltd. Tokyo (Japan); Inaba, H. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1994-09-05

    The loop type tubular bioreactor (TBR) was developed where biocatalysts are trapped in the reactor by membrane module. A UF membrane or MF membrane and crossflow filtration were adopted for the membrane module, and the reactor loop was composed of four membrane modules. The reactor was operated at 2-4 m/s in membrane surface velocity and 300-400 kPa in filtration pressure. As the result of the high-density culture of lactic acid bacteria and yeast, a biomass concentration was more than 10 times that in batch culture, suggesting the remarkable enhancement of a production efficiency. As the result of the continuous fermentation of cider, the fast fermentation more than 60 times that in conventional ones was obtained together with the same quality as conventional ones. Such a fast fermentation was probably achieved by yeast suspended in the fermenter of TBR, by yeast hardly affected physico-chemically as compared with immobilized reactors, and by small effect of mass transfer on reaction systems. 4 refs., 6 figs.

  12. The anesthetics influence (ethilic-eter and urethane) on renal radiopharmaceuticals

    International Nuclear Information System (INIS)

    Muramoto, E.; Achando, S.S.; Araujo, E.B. de; Hamada, H.S.; Silva Valente Goncalves, R. da; Pereira, N.P.S. de; Silva, C.P.G. da.

    1990-01-01

    A comparative study was done using anesthetics like ether ethilic and urethane, in rats (Wistar). A significative variation was observed in the results obtained when renal radiopharmaceuticals were investigated. Using urethane, the renal uptake increase progressivelly due to the inhibition of the renal filtration and it starts to recuperate when the anesthetic effect was eliminated. Using ether ethilic the radiopharmaceuticals are quickly eliminated from the kidneys (tubular or glomerular filtration), showing that the renal function was protected. (author) [pt

  13. Acute renal failure by ingestion of Euphorbia paralias

    Directory of Open Access Journals (Sweden)

    Karima Boubaker

    2013-01-01

    Full Text Available Euphorbia paralias is known in traditional medicine as an anti-inflammatory agent, a purgative and for its local anesthetic property. To the best our knowledge, renal toxicity of this substance has not been previously reported. In this paper, we report the case of a 29-year-old male who developed renal damage following ingestion of Euphorbia paralias. He had been on follow-up for nephrotic syndrome since 1986, although irregularly, with several relapses but each responding well to steroid therapy. A kidney biopsy had not been performed earlier due to refusal by the patient. He was off steroids since April 2008 because the patient developed osteoporosis. He was admitted with general malaise and oliguria to our department in May 2009, following repeated vomiting and watery diarrhea for three days. On examination, he was edematous but had normal vital signs except for a pulse rate of 120/min. Hemoglobin was only 5.5 g/dL but with normal white cell and platelet counts. Blood biochemistry showed evidence of advanced renal failure with a serum creatinine level of 1835 μmol/L and urea at 44.6 mmol/L, sodium of 132 μmol/L and potassium at 4.3 mmol/L. He had features of nephrotic syndrome with severe hypoproteinamia and 24-h urinary protein of 10.45 g. Ultrasonography revealed enlarged kidneys with a reduced echogenecity of the medulla and the papillae. Subsequently, after hemodialysis with blood transfusion, a kidney biopsy was performed that showed focal segmental glomerulosclerosis associated with an acute tubular injury. On intensive interrogation, the patient gave a history of ingesting boiled Euphorbia paralias as a native treatment for edema, ten days prior to the onset of the current illness. A diagnosis of acute renal failure (ARF resulting from the possible nephrotoxic effect of Euphorbia paralias poisoning was made. He was treated with intermittent hemodialysis and corticosteroids. Serum creatinine values improved after 48 days. At six

  14. Blockade of Death Ligand TRAIL Inhibits Renal Ischemia Reperfusion Injury

    International Nuclear Information System (INIS)

    Adachi, Takaomi; Sugiyama, Noriyuki; Gondai, Tatsuro; Yagita, Hideo; Yokoyama, Takahiko

    2013-01-01

    Renal ischemia-reperfusion injury (IRI) is a leading cause of acute kidney injury (AKI). Many investigators have reported that cell death via apoptosis significantly contributed to the pathophysiology of renal IRI. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor superfamily, and induces apoptosis and inflammation. However, the role of TRAIL in renal IRI is unclear. Here, we investigated whether TRAIL contributes to renal IRI and whether TRAIL blockade could attenuate renal IRI. AKI was induced by unilateral clamping of the renal pedicle for 60 min in male FVB/N mice. We found that the expression of TRAIL and its receptors were highly upregulated in renal tubular cells in renal IRI. Neutralizing anti-TRAIL antibody or its control IgG was given 24 hr before ischemia and a half-dose booster injection was administered into the peritoneal cavity immediately after reperfusion. We found that TRAIL blockade inhibited tubular apoptosis and reduced the accumulation of neutrophils and macrophages. Furthermore, TRAIL blockade attenuated renal fibrosis and atrophy after IRI. In conclusion, our study suggests that TRAIL is a critical pathogenic factor in renal IRI, and that TRAIL could be a new therapeutic target for the prevention of renal IRI

  15. Citrato y litiasis renal

    Directory of Open Access Journals (Sweden)

    Elisa E. Del Valle

    2013-08-01

    Full Text Available El citrato es un potente inhibidor de la cristalización de sales de calcio. La hipocitraturia es una alteración bioquímica frecuente en la formación de cálculos de calcio en adultos y especialmente en niños. El pH ácido (sistémico, tubular e intracelular es el principal determinante de la excreción de citrato en la orina. Si bien la mayoría de los pacientes con litiasis renal presentan hipocitraturia idiopática, hay un número de causas para esta anormalidad que incluyen acidosis tubular renal distal, hipokalemia, dietas ricas en proteínas de origen animal y/o dietas bajas en álcalis y ciertas drogas, como la acetazolamida, topiramato, IECA y tiazidas. Las modificaciones dietéticas que benefician a estos pacientes incluyen: alta ingesta de líquidos y frutas, especialmente cítricos, restricción de sodio y proteínas, con consumo normal de calcio. El tratamiento con citrato de potasio es efectivo en pacientes con hipocitraturia primaria o secundaria y en aquellos desordenes en la acidificación, que provocan un pH urinario persistentemente ácido. Los efectos adversos son bajos y están referidos al tracto gastrointestinal. Si bien hay diferentes preparaciones de citrato (citrato de potasio, citrato de sodio, citrato de potasio-magnesio en nuestro país solo está disponible el citrato de potasio en polvo que es muy útil para corregir la hipocitraturia y el pH urinario bajo, y reducir marcadamente la recurrencia de la litiasis renal.

  16. Carbohydrates in Ankistrodesmus braunii biomass cultivated in tubular photobioreactors

    Directory of Open Access Journals (Sweden)

    Ana Lucía Morocho-Jácome

    2017-12-01

    Full Text Available The great need for microalgae biomass production in tubular photobioreactors has increased for use in biofuels, pharmaceuticals and even cosmetic applications. In order to better understand the potential applications of this material, it is imperative to know in detail its composition. Ankistrodesmus braunii was cultivated in 3.5 L tubular air-lift photobioreactors using 10 mM sodium nitrate as nitrogen source in batch mode at 60 µmol photons m-2 s-1. The maximum biomass concentration (Xm and the biomass productivity (PX reached at 6th day of cultivation was 1249 ± 72 mg L-1 and 165 ± 13 mg L-1 d-1, respectively. Carbohydrates productivity expressed in terms of glucose, galactose and glucose+galactose (1:1 were 2.57 ± 0.04, 4.12 ± 0.06 and 3.22 ± 0.05 mg L-1 d-1, respectively. Results show a statistical difference that was found between carbohydrate productivity values expressed as glucose, galactose and glucose+galactose (1:1.

  17. Iatrogenic Digital Compromise with Tubular Dressings

    Directory of Open Access Journals (Sweden)

    Corre, Kenneth A

    2009-08-01

    Full Text Available Objective: This case report describes a digit amputation resulting from an improperly applied tubular dressing. The safe application of digital tubular dressings, and the rationale behind it, is detailed to raise emergency physician (EP awareness.Methods: We present a case report of a recent iatrogenic-induced digit ischemia caused by improperly applied tube gauze. We review the literature on the subject and the likely sources of poor outcomes presented. The proper application of tubular gauze dressings is then outlined.Conclusion: EPs and emergency department personnel must be educated on the safe application of tubular gauze dressings to avoid dire outcomes associated with improper applications.[WestJEM. 2009;10:190-192.

  18. Expression profiles of genes involved in xenobiotic metabolism and disposition in human renal tissues and renal cell models

    Energy Technology Data Exchange (ETDEWEB)

    Van der Hauwaert, Cynthia; Savary, Grégoire [EA4483, Université de Lille 2, Faculté de Médecine de Lille, Pôle Recherche, 59045 Lille (France); Buob, David [Institut de Pathologie, Centre de Biologie Pathologie Génétique, Centre Hospitalier Régional Universitaire de Lille, 59037 Lille (France); Leroy, Xavier; Aubert, Sébastien [Institut de Pathologie, Centre de Biologie Pathologie Génétique, Centre Hospitalier Régional Universitaire de Lille, 59037 Lille (France); Institut National de la Santé et de la Recherche Médicale, UMR837, Centre de Recherche Jean-Pierre Aubert, Equipe 5, 59045 Lille (France); Flamand, Vincent [Service d' Urologie, Hôpital Huriez, Centre Hospitalier Régional Universitaire de Lille, 59037 Lille (France); Hennino, Marie-Flore [EA4483, Université de Lille 2, Faculté de Médecine de Lille, Pôle Recherche, 59045 Lille (France); Service de Néphrologie, Hôpital Huriez, Centre Hospitalier Régional Universitaire de Lille, 59037 Lille (France); Perrais, Michaël [Institut National de la Santé et de la Recherche Médicale, UMR837, Centre de Recherche Jean-Pierre Aubert, Equipe 5, 59045 Lille (France); and others

    2014-09-15

    Numerous xenobiotics have been shown to be harmful for the kidney. Thus, to improve our knowledge of the cellular processing of these nephrotoxic compounds, we evaluated, by real-time PCR, the mRNA expression level of 377 genes encoding xenobiotic-metabolizing enzymes (XMEs), transporters, as well as nuclear receptors and transcription factors that coordinate their expression in eight normal human renal cortical tissues. Additionally, since several renal in vitro models are commonly used in pharmacological and toxicological studies, we investigated their metabolic capacities and compared them with those of renal tissues. The same set of genes was thus investigated in HEK293 and HK2 immortalized cell lines in commercial primary cultures of epithelial renal cells and in proximal tubular cell primary cultures. Altogether, our data offers a comprehensive description of kidney ability to process xenobiotics. Moreover, by hierarchical clustering, we observed large variations in gene expression profiles between renal cell lines and renal tissues. Primary cultures of proximal tubular epithelial cells exhibited the highest similarities with renal tissue in terms of transcript profiling. Moreover, compared to other renal cell models, Tacrolimus dose dependent toxic effects were lower in proximal tubular cell primary cultures that display the highest metabolism and disposition capacity. Therefore, primary cultures appear to be the most relevant in vitro model for investigating the metabolism and bioactivation of nephrotoxic compounds and for toxicological and pharmacological studies. - Highlights: • Renal proximal tubular (PT) cells are highly sensitive to xenobiotics. • Expression of genes involved in xenobiotic disposition was measured. • PT cells exhibited the highest similarities with renal tissue.

  19. Renal nerves and nNOS

    DEFF Research Database (Denmark)

    Kompanowska-Jezierska, Elzbieta; Wolff, Helle; Kuczeriszka, Marta

    2008-01-01

    ). This was tested by NaLoad after chronic renal denervation with and without inhibition of nNOS by S-methyl-thiocitrulline (SMTC). In addition, the acute effects of renal denervation on MABP and sodium balance were assessed. Rats were investigated in the conscious, catheterized state, in metabolic cages...... of acutely and chronically denervated rats were less than control (15% and 9%, respectively, P reduced by renal denervation (14.5 +/- 0.2 vs. 19.3 +/- 1.3 mIU/l, P reduced...... PRC (P sodium excretion six-fold, irrespective of renal denervation and SMTC. The metabolic data demonstrated that renal denervation lowered sodium balance during the first days after denervation (P

  20. Mucinous tubular and spindle cell carcinoma of kidney: A rare case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Geramizadeh Bita

    2009-10-01

    Full Text Available Low grade mucinous tubular and spindle cell carcinoma of kidney was newly established as a distinct renal cell carcinoma in the World Health Organization (WHO classification of 2004. Until now, less than 60 cases have been reported and the largest series represented approximately 15 patients with this type of tumor. Herein, we report a case of mucinous tubular and spindle cell carcinoma in a 63-year-old male presented with right flank pain which was diagnosed after nephrectomy. Pathologists should consider this diagnosis and its spectrum of histopathologic features in mind to ensure an accurate diagnosis.

  1. MR Imaging of renal transplants

    International Nuclear Information System (INIS)

    Gremo, L.; Avataneo, T.; Potenzoni, F.; Colla, L.; Segoloni, G.

    1988-01-01

    The authors report their experience in the study of renal transplant recipients by MR, in order to determine its clinical potentials. The main purpose of this work is to focus on MR patterns in relation to clinical findings of rejector or normally fuctioning kidney. Twenty-four patients were examined with a 0.5 T superconductive magnete, body coil, spin-echo pulse sequence (SE) and inversion-recovery (IR). MRI patterns could be seen in normally functioning kidneys and transplant rejections, while variable MRI findings were observed in transplants with acute tubular necrosis (ATN). In the normally functioning transplanted kidney there is a clear corticomedullary differentiation (CMD), and the extent of vascular penetration into the renal parenchyma is clearly seen. In transplant rejection, CMD is either diminished or absent, and there is no vascular penetration into the parenchyma; to differentiate acute from chronic rejections, the increase/decrease in renal size and the change in renal shape (spherical shape in acute transplant rejection) respectively must be observed. MRI proves thus to be useful in the study of renal transplants, even in case of questionable clinical findings, and in patients in whom renal biopsy is contraindicated

  2. Radionuclide dynamic renal imaging for renal function study in patients with NIDDM

    International Nuclear Information System (INIS)

    Yang Ruiping; Qu Wanying; Gao Wenping

    1996-01-01

    Radionuclide dynamic renal imaging was performed to gain evidence for further treatment and evaluation of prognosis in patients with non-insulin-dependent diabetes mellitus (NIDDM). 99m Tc-DTPA dynamic renal imaging was performed in 137 NIDDM patients and 44 normal controls (NC). Glomerular filtration rate (GFR) and renogram were acquired simultaneously. Renal tubular secretion function was measured with 99m Tc-EC in 126 of the 137 diabetics and 17 NC. GFR decreased in all patients with different duration of NIDDM and the difference was remarkably significance in comparison with NC (t = 7.17∼13.73, P 99m Tc-EC. This study showed that the function of glomerular filtration and tubular secretion were both damaged in all diabetics. Their magnitude was aggravated with the prolongation of the course of disease

  3. Enteric-coated mycophenolate sodium.

    Science.gov (United States)

    Gabardi, Steven; Tran, Jennifer L; Clarkson, Michael R

    2003-11-01

    To review the pharmacology, pharmacokinetics, efficacy, and safety of mycophenolate sodium. Primary literature was obtained via a MEDLINE search (1966-June 2003). Abstracts were obtained from the manufacturer and included in the analysis. All studies and abstracts evaluating mycophenolate sodium in solid organ transplantation were considered for inclusion. English-language studies and abstracts were selected for inclusion, but were limited to those consisting of human subjects. Mycophenolate sodium, a mycophenolic acid prodrug, is an inhibitor of T-lymphocyte proliferation. Mycophenolic acid reduces the incidence of acute rejection in renal transplantation. Mycophenolate sodium is enteric coated and has been suggested as a potential method to reduce the gastrointestinal adverse events seen with mycophenolate mofetil. Both mycophenolate mofetil and mycophenolate sodium have been shown to be therapeutically equivalent at decreasing the incidence of allograft rejection and loss. The frequency of adverse events is similar between both compounds, with the most common events being diarrhea and leukopenia. Mycophenolate sodium is effective in preventing acute rejection in renal transplant recipients. At doses of 720 mg twice daily, the efficacy and safety profiles are similar to those of mycophenolate mofetil 1000 mg twice daily. Mycophenolate sodium has been approved in Switzerland; approval in the US is pending.

  4. Renal handling of drugs in renal failure. I: Differential effects of uranyl nitrate- and glycerol-induced acute renal failure on renal excretion of TEAB and PAH in rats

    International Nuclear Information System (INIS)

    Lin, J.H.; Lin, T.H.

    1988-01-01

    Two etiologically different models of experimental acute renal failure were induced in rats by administration of either glycerol or uranyl nitrate. Both compounds caused a substantial decrease in the glomerular filtration rate (GFR) and the net tubular secretion of tetraethylammonium bromide (TEAB) and para-aminohippuric acid (PAH). The degree of renal impairment induced by uranyl nitrate and glycerol appeared to be dose related. Deprivation of drinking water 24 hr before the administration of glycerol potentiated the renal damage. In uranyl nitrate-induced renal failure, the decline of the net tubular secretion for TEAB and PAH was not proportional to the decrease in GFR; the secretion process deteriorated faster than the GFR. For example, when 0.5 mg/kg uranyl nitrate was administered, GFR fell to approximately 65% of normal, whereas the net tubular secretion was decreased to 30% of normal. These results suggest that the tubular transport was preferentially affected by uranyl nitrate. In contrast, in glycerol-induced renal failure, the decline of TEAB secretion fell in a parallel fashion with the GFR, suggesting that the glomeruli and the proximal tubules were equally damaged by glycerol. However, in this latter model, the decline of PAH secretion did not parallel the decrease in GFR, contradicting the proposal that glycerol affects equally the glomeruli and the proximal tubules. This discrepancy may be due to the selective competitive inhibition of PAH secretion by the accumulation of naturally occurring organic acids

  5. Tubular localization and expressional dynamics of aquaporins in the kidney of seawater-challenged Atlantic salmon

    DEFF Research Database (Denmark)

    Engelund, Morten Buch; Madsen, Steffen S

    2015-01-01

    Most vertebrate nephrons possess an inherited ability to secrete fluid in normal or pathophysiological states. We hypothesized that renal aquaporin expression and localization are functionally regulated in response to seawater and during smoltification in Atlantic salmon and thus reflect a shift...... in renal function from filtration towards secretion. We localized aquaporins (Aqp) in Atlantic salmon renal tubular segments by immunohistochemistry and monitored their expressional dynamics using RT-PCR and immunoblotting. Three aquaporins: Aqpa1aa, Aqp1ab and Aqp8b and two aquaglyceroporins Aqp3a and Aqp......10b were localized in the kidney of salmon. The staining for all aquaporins was most abundant in the proximal kidney tubules and there was no clear effect of salinity or developmental stage on localization pattern. Aqp1aa and Aqp3a were abundant apically but extended throughout the epithelial cells...

  6. Nonlinear interactions in renal blood flow regulation

    DEFF Research Database (Denmark)

    Marsh, Donald J.; Sosnovtseva, Olga; Chon, Ki H.

    2005-01-01

    We have developed a model of tubuloglomerular feedback (TGF) and the myogenic mechanism in afferent arterioles to understand how the two mechanisms are coupled. This paper presents the model. The tubular model predicts pressure, flow, and NaCl concentration as functions of time and tubular length...... hydrostatic pressure, and plasma flow rate. The arteriolar model predicts fraction of open K channels, intracellular Ca concentration (Ca-i), potential difference, rate of actin - myosin cross bridge formation, force of contraction, and length of elastic elements, and was solved for two arteriolar segments...... resistance and glomerular capillary pressure. The model couples TGF input to voltage-gated Ca channels. It predicts autoregulation of GFR and renal blood flow, matches experimental measures of tubular pressure and macula densa NaCl concentration, and predicts TGF-induced oscillations and a faster smaller...

  7. Long-term enzyme replacement therapy is associated with reduced proteinuria and preserved proximal tubular function in women with Fabry disease

    DEFF Research Database (Denmark)

    Prabakaran, Thaneas; Birn, Henrik; Bibby, Bo M

    2014-01-01

    dysfunction in women with Fabry disease treated with ERT. METHODS: A retrospective, single centre, cohort study evaluated the long-term association between ERT, albuminuria and eGFR in 13 women with Fabry disease and mild renal involvement. In particular, we analysed the changes in the proteinuric profile...... to end-stage renal failure. In women with Fabry disease, accumulation of GL-3 in the glomerular podocytes and other renal cells induces progressive, proteinuric nephropathy, but not as severe as in men. Enzyme replacement therapy (ERT) with recombinant α-Gal A reduces cellular GL-3 deposits in podocytes...... in albuminuria was paralleled by a decrease in both glomerular and tubular urine protein markers. CONCLUSIONS: The data indicate that long-term ERT is associated with a reduction in albuminuria and glomerular and tubular urinary protein markers in women with Fabry disease and mild renal manifestations....

  8. Renal disease and mitochondrial genetics.

    Science.gov (United States)

    Rötig, Agnès

    2003-01-01

    Respiratory chain (RC) deficiencies have long been regarded as neuromuscular diseases mainly originating from mutations in the mitochondrial DNA. Oxidative phosphorylation, i.e. adenosine triphosphate (ATP) synthesis-coupled electron transfer from substrate to oxygen through the RC, does not occur only in the neuromuscular system. Therefore, a RC deficiency can theoretically give rise to any symptom, in any organ or tissue, at any age and with any mode of inheritance, owing to the dual genetic origin of RC enzymes (nuclear DNA and mitochondrial DNA). Mitochondrial diseases can give rise to various syndromes or association, namely, neurologic and neuromuscular diseases, cardiac, renal, hepatic, hematological and endocrin or dermatological presentations. The most frequent renal symptom is proximal tubular dysfunction with a more or less complete de Toni-Debre-Fanconi Syndrome. A few patients have been reported with tubular acidosis, Bartter Syndrome, chronic tubulointerstitial nephritis or nephrotic syndrome. The diagnosis of a RC deficiency is difficult when only renal symptoms are present, but should be easier when another, seemingly unrelated symptom is observed. Metabolic screening for abnormal oxidoreduction status in plasma, including lactate/pyruvate and ketone body molar ratios, can help to identify patients for further investigations. These include the measurement of oxygen consumption by mitochondria and the assessment of mitochondrial respiratory enzyme activities by spectrophotometric studies. Any mode of inheritance can be observed: sporadic, autosomal dominant or recessive, or maternal inheritance.

  9. Effects of sodium-glucose co-transporter 2 (SGLT2 inhibition on renal function and albuminuria in patients with type 2 diabetes: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Lubin Xu

    2017-06-01

    Full Text Available Aim To evaluate the effects of sodium-glucose co-transporter 2 (SGLT2 inhibition on renal function and albuminuria in patients with type 2 diabetes. Methods We conducted systematic searches of PubMed, Embase and Cochrane Central Register of Controlled Trials up to June 2016 and included randomized controlled trials of SGLT2 inhibitors in adult type 2 diabetic patients reporting estimated glomerular filtration rate (eGFR and/or urine albumin/creatinine ratio (ACR changes. Data were synthesized using the random-effects model. Results Forty-seven studies with 22,843 participants were included. SGLT2 inhibition was not associated with a significant change in eGFR in general (weighted mean difference (WMD, −0.33 ml/min per 1.73 m2, 95% CI [−0.90 to 0.23] or in patients with chronic kidney disease (CKD (WMD −0.78 ml/min per 1.73 m2, 95% CI [−2.52 to 0.97]. SGLT2 inhibition was associated with eGFR reduction in short-term trials (WMD −0.98 ml/min per 1.73 m2, 95% CI [−1.42 to −0.54], and with eGFR preservation in long-term trials (WMD 2.01 ml/min per 1.73 m2, 95% CI [0.86 to 3.16]. Urine ACR reduction after SGLT2 inhibition was not statistically significant in type 2 diabetic patients in general (WMD −7.24 mg/g, 95% CI [−15.54 to 1.06], but was significant in patients with CKD (WMD −107.35 mg/g, 95% CI [−192.53 to −22.18]. Conclusions SGLT2 inhibition was not associated with significant changes in eGFR in patients with type 2 diabetes, likely resulting from a mixture of an initial reduction of eGFR and long-term renal function preservation. SGLT2 inhibition was associated with statistically significant albuminuria reduction in type 2 diabetic patients with CKD.

  10. Thermal CFD Analysis of Tubular Light Guides

    Directory of Open Access Journals (Sweden)

    Ondřej Šikula

    2013-12-01

    Full Text Available Tubular light guides are applicable for daylighting of windowless areas in buildings. Despite their many positive indoor climate aspects they can also present some problems with heat losses and condensation. A computer CFD model focused on the evaluation of temperature distribution and air flow inside tubular light guides of different dimensions was studied. The physical model of the tested light guides of lengths more than 0.60 m proves shows that Rayleigh numbers are adequate for a turbulent air flow. The turbulent model was applied despite the small heat flux differences between the turbulent and laminar model. The CFD simulations resulted into conclusions that the growing ratio of length/diameter increases the heat transmission loss/linear transmittance as much as by 50 percent. Tubular light guides of smaller diameters have lower heat transmission losses compared to the wider ones of the same lengths with the same outdoor temperature being taken into account. The simulation results confirmed the thermal bridge effect of the tubular light guide tube inside the insulated flat roof details. The thermal transmittance of the studied light guides in the whole roof area was substituted with the point thermal bridges. This substitution gives possibility for simple thermal evaluation of the tubular light pipes in roof constructions.

  11. Renal Osteodystrophy

    Directory of Open Access Journals (Sweden)

    Aynur Metin Terzibaşoğlu

    2004-12-01

    Full Text Available Chronic renal insufficiency is a functional definition which is characterized by irreversible and progressive decreasing in renal functions. This impairment is in collaboration with glomeruler filtration rate and serum creatinine levels. Besides this, different grades of bone metabolism disorders develop in chronic renal insufficiency. Pathologic changes in bone tissue due to loss of renal paranchyme is interrelated with calcium, phosphorus vitamine-D and parathyroid hormone. Clinically we can see high turnover bone disease, low turnover bone disease, osteomalacia, osteosclerosis and osteoporosis in renal osteodystropy. In this article we aimed to review pathology of bone metabolism disorders due to chronic renal insufficiency, clinic aspects and treatment approaches briefly.

  12. Lack of effect of non-steroid antiinflammatory drugs on lithium clearance and on delivery of tubular fluid to the loop of Henle in rats.

    Science.gov (United States)

    Lassen, E; Thomsen, K; Sørensen, S S; Pedersen, E B

    1986-11-01

    This paper examines a possible interaction between non-steroid antiinflammatory drugs (NSAI drugs) and renal lithium clearance in conscious, unoperated rats with diabetes insipidus (Brattleboro strain) and ordinary Wistar rats. The drugs were given with the food for 5 days before clearance determinations in the following daily doses per kg body weight: acetylsalicyclic acid 115 mg/kg, phenylbutazone 20 mg/kg, indomethacin 5 mg/kg, and penicillamine 65 mg/kg. None of the drugs affected the lithium clearance. Also urine flow, sodium clearance, potassium clearance, and prostaglandin E2 excretion remained unaffected by the treatments. The results suggest that a continued lowering of lithium clearance cannot be produced, at least not by administration of the drugs with the food. Since lithium clearance is a quantitative measure of the delivery of tubular fluid from the proximal tubules to the loop of Henle, the results also suggest that chronic administration of NSAI drugs does not influence delivery from the proximal tubules in rats. The lowering of lithium clearance observed by others after administration of the drugs by injection or by gastric tube may have been transient, lasting only for a short period after each administration.

  13. Insulin-like growth factor-1 sustains stem cell mediated renal repair.

    NARCIS (Netherlands)

    Imberti, B.; Morigi, M.; Tomasoni, S.; Rota, C.; Corna, D.; Longaretti, L.; Rottoli, D.; Valsecchi, F.; Benigni, A.; Wang, J.; Abbate, M.; Zoja, C.; Remuzzi, G.

    2007-01-01

    In mice with cisplatin-induced acute kidney injury, administration of bone marrow-derived mesenchymal stem cells (MSC) restores renal tubular structure and improves renal function, but the underlying mechanism is unclear. Here, we examined the process of kidney cell repair in co-culture experiments

  14. Transition piece for joining together tubular pieces

    International Nuclear Information System (INIS)

    Holko, K.H.

    1981-01-01

    A transition piece for joining together tubular pieces formed respectively from a low alloy or carbon steel and a high temperature alloy containing at least 16% chromium includes a plurality of tubular parts welded together and formed from materials of selected composition with a maximum chromium content difference of 5% between adjacent parts when the chromium content of each part is below 10% and a maximum chromium difference of 7% between adjacent parts when the chromium content of either part is above 10%. The transition parts are also graded as to such characteristics as thermal expansion coefficient. The transition parts at opposite ends of the transition joint have chromium percentages similar to the tubular pieces to which they are to be joined. The parts may be joined by fusion and/or friction welding and parts may be formed by fusion weld deposition. (author)

  15. Hypophosphatemia in a Malnourished Child: When Renal Fanconi Syndrome Does Not Stand for Refeeding Syndrome.

    Science.gov (United States)

    Runde, Joseph; Rivera-Rivera, Edgardo; Pompeii-Wolfe, Cecelia; Clardy, Christopher; Sentongo, Timothy

    2018-05-10

    Refeeding syndrome is diagnosed based on the onset of multiple laboratory abnormalities (most commonly hypophosphatemia) and clinical signs in the setting