Increased Urine Volume Research Articles

Preliminary Report of Intravenous Tolvaptan Sodium Phosphate (Samtas®) Treatment in Decompensated Heart Failure

Background: Tolvaptan sodium phosphate (Samtas®; Otsuka Pharmaceutical, Tokyo, Japan) is a novel intravenous aquaretic diuretic aimed at individuals experiencing advanced congestion refractory to conventional diuretics and having difficulty with oral intake. Despite its potential, the true efficacy and practicality of this compound within real-world clinical settings remain obscure. Methods: A retrospective analysis of clinical data was conducted, examining trends among consecutive in-hospital patients diagnosed with congestive heart failure who underwent treatment with tolvaptan sodium phosphate at a prominent academic medical center between June 2022 and June 2023. Results: Twenty-one patients were enrolled (median age: 75 years, serum N-terminal pro B-type natriuretic peptide: 8941 pg/mL). Among them, 14 patients (67%) received non-invasive/invasive positive-pressure ventilation, and 17 patients (81%) concurrently received intravenous inotropes. Subsequent to the initiation of tolvaptan sodium phosphate treatment, a significant increase in urine volume was observed on the following day (p = 0.036). Urine osmolality decreased from 356 (318, 443) at baseline to 247 (176, 333) mOsm/kg after 4 h (p = 0.002). No occurrences of hypernatremia were recorded during the therapeutic period. Notably, two patients transitioned from tolvaptan sodium phosphate treatment to continuous hemodiafiltration due to insufficient efficacy. Conclusions: In routine clinical practice, intravenous tolvaptan sodium phosphate exhibits potential efficacy and practicability in the majority of congestive heart failure patients exhibiting refractory congestion, unstable hemodynamics, and challenges with oral intake.

Promoting fluid intake to increase urine volume for kidney stone prevention: Protocol for a randomized controlled efficacy trial of the sipIT intervention

BackgroundRisk of kidney stone recurrence can be reduced by increasing fluid intake and urine production but most patients fail to adhere to recommended clinical guidelines. Patients have indicated that common barriers to fluid intake include a lack of thirst, forgetting to drink, and not having access to water. We developed the sipIT intervention to support patients' fluid intake with semi-automated tracking (via a mobile app, connected water bottle and a smartwatch clockface that detects drinking gestures) and provision of just-in-time text message reminders to drink when they do not meet the hourly fluid intake goal needed to achieve the recommended volume. This trial evaluates the efficacy of sipIT for increasing urine output in patients at risk for recurrence of kidney stones. Method/designAdults with a history of kidney stones and lab-verified low urine production (<2 L/day) will be randomly assigned to receive either usual care (education and encouragement to meet fluid intake guidelines) or usual care plus the sipIT intervention. The primary outcome is 24-h urine volume; secondary outcomes include urinary supersaturations, past week fluid intake, and experienced automaticity of fluid intake. Outcomes will be assessed at baseline, 1 month, 3 months, and 12 months. ConclusionsThe sipIT intervention is the first to prompt periodic fluid intake through integration of just-in-time notifications and semi-automated tracking. If sipIT is more efficacious than usual care, this intervention provides an innovative treatment option for patients needing support in meeting fluid intake guidelines for kidney stone prevention.

Adaptation mechanism of Phan Rang sheep to salinity in drinking water under tropical conditions.

The aims of this study were to determine adaptation mechanism of sheep to salinity in drinking water. A group of 10 male sheep were used in a 6-week of experiment, with 1week for pre-treatment period (Week 1), 4weeks for during treatment period (Week 2 to Week 5), and 1week for posttreatment period (Week 6). During the pre- and posttreatment periods, sheep consumed with fresh water. However, during treatment period, they were given with diluted seawater (DSW) at concentrations of 0.5%, 1.0%, 1.5%, and 2% for Weeks 2, 3, 4, and 5, respectively. Animal was offered 300 g concentrate and corn stover silage for ab libitum. Dry matter intake decreased as DSW increased, whereas sheep drinking DSW showed an increase in water intake and urine volume (p < 0.05). Body weight change decreased in 2% DSW. Sheep consuming 2% DSW exhibited higher plasma electrolyte levels compared to other groups. But plasma levels of AST, ALT, and creatinine were unaffected by DSW (p > 0.05). The elevated levels and excretions of urinary electrolytes were found in DSW groups (p < 0.05). Water balance was unaffected by DSW, except during the recovery period. It concluded that adapted sheep can consume DSW up to 1.5% without harmful effects.

Evaluation of Diuretic Activity of Aqueous and Hydro Methanolic Crude Extracts and Solvent Fraction of the Hydromethanolic Flower Extract of Erica Arborea L. (Ericaceae) in Swiss Albino Mice.

To evaluate the diuretic effects of aqueous (AQ) and hydromethanolic crude extract (HM) the as well as the solvent fractions of the HM extract from Erica arborea flowers in mice. Mice were administered AQ and HM crude extracts, along with solvent fractions of HM extracts of E. arborea flowers, including HXF (n-hexane fraction), EAF (ethyl acetate fraction), and AQF (aqueous fraction), at doses ranging from 100 to 400 mg/kg orally. The effects of these extracts and solvent fractions on urine and salt excretion over 5 hours were compared to the effects of the solvent used for reconstitution and a standard drug (furosemide 10 mg/kg), as well as to each other. The HM crude extract at a lower dose (100 mg/kg) significantly increased urine volume and salt excretion starting from the 3rd h compared to the AQ crude extract. Similar effects were observed for EAF. Notably, the HM extract and its EAF at 400 mg/kg showed comparable urine and salt excretion profiles to the standard drug. This study demonstrated that HM extract and EAF promote better diuresis, likely due to their saluretic properties. Furthermore, it confirms the diuretic activity of Erica arborea flowers.

Analisis CT Scan Urografi dengan Klinis Batu Saluran Kemih di Instalasi Radiologi Rumah Sakit Bhayangkara Makassar

Background: Urinary tract stones are the growth of hard, stone-like masses in the human urinary tract. The prevalence of urinary tract stones (BSK) in Indonesia is still not known for certain, but estimates suggest that there are around 170,000 cases of BSK every year. CT Scan is a radiological examination modality for diagnosing urinary tract stones with a sensitivity level of around 95%-100% and a specificity level of around 96%-98% for detecting urinary tract stones, so CT Scan is considered the gold standard in diagnosing this condition. Research Objectives: This study aims to determine the management of CT Scan Urography in clinical urinary tract stones in the Radiology Installation of Bhayangkara Hospital, Makassar. Method: This research used descriptive qualitative research with a case study approach, the research subjects consisted of 3 radiographers, 1 radiologist, and 1 sending doctor. Data collection was carried out through several stages, namely observation, interviews and documentation. Results: The results of research at the Radiology Installation of Bhayangkara Hospital, Makassar. The procedure for CT Scan Urography examinations in clinical urinary tract stones is that the patient drinks 750 ml of fresh tea until he feels like he wants to urinate, then the examination is carried out. The role and effect of giving plain tea can increase HU (Hounsfield Unit) density and also speed up diuresis, thereby helping to shorten examination time. The excess caffeine content of plain tea can speed up the process of increasing urine volume, thereby shortening the examination time..

Effectiveness of avocado leaf extract (Persea americana Mill.) as antihypertensive

Background Avocado leaves (Persea americana Mill.) have been traditionally used as antihypertensive. Various studies have tested the benefits of the Persea americana Mill. in treating hypertension but still using extracts not yet using nanoparticles. Therefore, this study aims to study the effectiveness of avocado leaf extract, including the nanoparticles, on salt-induced hypertensive Wistar rats in inhibiting the ACE enzyme, which causes decreasing systolic blood pressure (SBP) and diastolic blood pressure (DBP) as well as increasing urine volume. Methods This study used an experimental in vivo study design involving 24 white male Wistar rats (Rattus norvegicus), aged 2–3 months, weighing 130–250 g, and of a healthy condition with active movement. The samples were randomly divided into six treatment groups and post-test only research design with control group design. Results The result of the study showed that the extract contained a quercetin of 1129.597 ppm and 10 mineral compounds, including potassium, with the highest content. The analysis of antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl method showed that the antioxidant activity at IC50 was 44.734 ppm. The P. americana leaf extract nanoparticles had the most significant result in reducing blood pressure in Wistar rats induced by 16% NaCl for 14 days SBP to normal was by 68.75 mmHg (175.00±21.57 mmHg to 106.25±9.21 mmHg) and 55.25 mmHg (128.42±25.75 mmHg to 73.17±15.75 mmHg), respectively. Also, avocado leaf extract caused the decrease of SBP from 164.92±7.16 mmHg to 116.83±6.36 mmHg and DBP from 118.42±16.24 mmHg to 82.83±6.47 mmHg. The P. americana leaf extract nanoparticles resulted in the most urine volume at 13.5 ml, with the highest DAI value of 2.25. The ACE inhibitor test using the ELISA method showed that the P. americana leaf extract and the nanoparticle extract inhibition against the ACE enzyme were 60.0±12.1 % and 59.5±3%, respectively. The mean serum nitrate as a result of P. americana leaf extract (K4) and nanoparticles of P. americana leaf extract (K5) were 44.0±9.0 μmol/L and 41.1±11.5 μmol/L, respectively. The mean of serum nitrite was led by P. americana leaf extract (K4), and nanoparticles of P. americana leaf extract (K5) were 83.7±24.0 μmol/L and 81.0±23.2 μmol/L, sequentially. Conclusions The study showed that the leaf extract and nanoparticle extract of Persea americana Mill. was effective as an antihypertensive.

Acute over-additive natriuretic effects by a combination of finerenone and SGLT2 inhibition in rats with an activated renin-angiotensin-aldosterone system: a mechanistic basis for clinical outcomes?

Abstract Background Recent preclinical studies suggested an independent benefit of non-steroidal mineralocorticoid receptor (MR) antagonism by finerenone and SGLT2 inhibition in cardiorenal diseases, with a potential for combination therapy. Chronic low-dose combination of finerenone and empagliflozin in hypertensive rats revealed an early, sustained and over-additive reduction in proteinuria but the underlying mechanism(s) are not fully understood. Purpose To compare the acute glucosuric, natriuretic, kaliuretic and diuretic efficacy of individual dosages of finerenone and SGLT2 inhibitors (empagliflozin, canagliflozin or dapagliflozin) with the combined administration of both drug classes in conscious rats with an activated renin-angiotensin-aldosterone system (RAAS). Methods The RAAS was activated in male Wistar rats (body mass 250 to 500 g) by placing them on a low-salt diet containing 0.02% sodium chloride for 72 hours. In a series of three independent experiments, finerenone (1 mg/kg), SGLT2 inhibitor (3 mg/kg; either empagliflozin, canagliflozin or dapagliflozin) alone and the respective combinations were administered in 2-3 ml/kg of solvent (PEG400) by oral gavage and the animals (n=6-10 / group) were individually placed in metabolic cages on water ad libitum. The individual urine was collected for 24 hours and the concentration of glucose, sodium and potassium excreted in the urine was measured by a clinical-chemical analyzer system (ADVIA 2400). Results Administration of 1 mg/kg finerenone had no influence on urinary glucose, urinary volume and urinary potassium but caused an increase in urinary sodium excretion at least by trend. At a dose of 3 mg/kg, all SGLT2 inhibitors induced a strong increase in urinary glucose excretion but had no significant influence on urinary potassium and urinary sodium, while only dapagliflozin caused an increase in urinary volume at the tested dose. Administration of a combination of 1 mg/kg finerenone and 3 mg/kg SGLT2 inhibitor did not significantly modify urinary glucose and urinary potassium in comparison to the respective individual finerenone and SGLT2 inhibitor dosages and only the combination with empagliflozin increased urinary volume vs the respective monotherapies. Surprisingly, combination of finerenone with SGLT2 inhibition over-additively induced sodium excretion consistently in all three experiments (finerenone+empagliflozin: 171,4%; finerenone+canagliflozin: 139,6%; finerenone+dapagliflozin: 133,9%) in comparison to the calculated combination (set to 100%) of the respective individual finerenone and SGLT2 inhibitor groups. Conclusion Combination of MR antagonism by finerenone and SGLT2 inhibition revealed an acute over-additive natriuresis in a rat diuresis model. This might provide an additional mechanistic basis for near-term (e.g. hospitalization for heart failure) and long-term outcomes (e.g. blockade of the progression of kidney failure) in cardiorenal patient populations.

Diuretic, Natriuretic, And Ca2+-Sparing Effect Of The Alkaloid Boldine In Rats

Abstract Background Previous studies indicate the renal vasodilating effects of boldine, an alkaloid found in Peumus boldus. However, its potential to induce diuresis still needs to be studied. Methods Wistar rats were used and the urine volume was noted for 8 h and further studied. Results The acute treatment at 0.1 and 0.3 mg/kg of boldine showed a diuretic, natriuretic, and Ca2+-sparing effect in rats without changing the urinary elimination of K+and Cl-. When boldine was given in combination with hydrochlorothiazide, there was an increase in urinary volume compared to the vehicle group. However, this was not different from the treatments in its isolated form. Urine Ca2+values ​​remained low but were not enhanced by this association. The excretion of Na+and Cl- was significantly increased compared to the group that received only vehicle or boldine. On the other hand, although the association of amiloride plus boldine did not result in a diuretic effect, the increase in Na+and the reduction in K+excretion were significantly potentiated. Furthermore, in the presence of the non-selective muscarinic receptor antagonist atropine, boldine showed reduced capacity to increase urinary volume, maintaining the natriuretic and Ca2+-sparing effect, besides a very evident K+-sparing action. Similar results were obtained in the presence of the non-selective cyclooxygenase inhibitor indomethacin. Furthermore, boldine showed an ex vivo antiurolithiasis activity, reducing calcium oxalate’s precipitation and crystallization. Conclusions This study reveals the diuretic, natriuretic, Ca2+-sparing, and antiurolithiatic effects of boldine, an action possibly related to muscarinic receptor activation and prostanoid generation.

Combined Inhibition of Phosphodiesterase-5 and -9 in Experimental Heart Failure

BackgroundIntracellular second messenger cyclic guanosine monophosphate (cGMP) mediates bioactivity of the natriuretic peptides and nitric oxide, and is key to circulatory homeostasis and protection against cardiovascular disease. Inhibition of cGMP-degrading phosphodiesterases (PDEs) PDE5 and PDE9 are emerging as pharmacological targets in heart failure (HF). ObjectivesThe present study investigated dual enhancement of cGMP in experimental HF by combining inhibition of PDE-5 (P5-I) and PDE-9 (P9-I). MethodsEight sheep with pacing-induced HF received on separate days intravenous P5-I (sildenafil), P9-I (PF-04749982), P5-I+P9-I, and vehicle control, in counterbalanced order. ResultsCompared with control, separate P5-I and P9-I significantly increased circulating cGMP concentrations in association with reductions in mean arterial pressure (MAP), left atrial pressure (LAP), and pulmonary arterial pressure (PAP), with effects of P5-I on cGMP, MAP, and PAP greater than those of P9-I. Only P5-I decreased pulmonary vascular resistance. Combination P5-I+P9-I further reduced MAP, LAP, and PAP relative to inhibition of either phosphodiesterase alone. P9-I and, especially, P5-I elevated urinary cGMP levels relative to control. However, whereas inhibition of either enzyme increased urine creatinine excretion and clearance, only P9-I induced a significant diuresis and natriuresis. Combined P5-I+P9-I further elevated urine cGMP with concomitant increases in urine volume, sodium and creatinine excretion, and clearance similar to P9-I alone, despite the greater MAP reductions induced by combination treatment. ConclusionsCombined P5-I+P9-I amalgamated the superior renal effects of P9-I and pulmonary effects of P5-1, while concurrently further reducing cardiac preload and afterload. These findings support combination P5-I+P9-I as a therapeutic strategy in HF.

Effects of Parenteral Nutrition with Amino Acid Alone and Amino Acid-Intralipid Combination on Vital Signs and Rate of Diuresis in ICU Patients

Background: Nearly all cases admitted to intensive care units (ICUs) suffer from poor nutritional status. Accordingly, the type of parenteral nutrition administered can influence these patients’ health conditions. Objectives: This study aimed to compare the effects of parenteral nutrition with the amino acid alone and amino acid-intralipid combination on vital signs and rate of diuresis in ICU patients. Methods: This prospective cohort study was conducted over two years, from March 2021 to March 2023. Patients under intravenous nutrition with amino acid (Group A) and amino acid-intralipid (Group B) for three days (as ordered by the ICU specialist) were examined. The patients' vital signs and laboratory findings were recorded before and after the nutrition. The data were analyzed using SPSS v. 26. Results: The patients were homogeneous regarding age, sex, disease history, and diagnosis (P &lt; 0.05). After parenteral feeding, urine and blood urea nitrogen/creatinine ratio respectively increased and decreased in Group B. Moreover, the serum bilirubin level significantly decreased in Group B, and SGOT and SGPT increased in Group A. In addition, the breathing rate significantly increased in Group A after intravenous feeding (P &lt; 0.001). Conclusions: Although intravenous amino acid-intralipid nutrition increased and decreased urine and blood urea nitrogen/creatinine, respectively, the patients who received amino acid alone also experienced an increase in urine volume and respiratory rate. Therefore, intravenous amino acid nutrition alone can be cost-effective.

Effect of a high-citrate beverage on urine chemistry in patients with calcium kidney stones.

A well-accepted strategy to prevent kidney stones is to increase urine volume by increasing oral intake of fluids, especially water, to lower supersaturation of the relevant, relatively insoluble salts, and thereby lower the risk of precipitation. Randomized controlled trials have shown that this strategy works. It is inexpensive, safe, and intuitively attractive to patients. However, although any beverage can increase urine volume, and citrus juices can increase urine citrate content and pH, no beverage other than water has been clearly shown by randomized controlled trial to prevent kidney stones. We designed an innovative, palatable, low-calorie, high alkali citrate beverage to prevent kidney stones, called Moonstone. One packet of Moonstone powder, mixed in 500ml of water, contains 24.5meq of alkali citrate. We administered one packet twice a day to ten calcium stone formers. Moonstone resulted in an increase in mean 24-h urine citrate and urine pH, and a decrease in supersaturation of calcium oxalate in calcium stone formers compared to an equal volume of water. These changes, comparable to those seen in a prior study of a similar amount of (potassium-magnesium) citrate, will likely be associated with a clinically meaningful reduction in kidney stone burden in patients with calcium stones. The effect to increase urine pH would also be expected to benefit patients with uric acid and cystine stones, groups that we hope to study in a subsequent study. The study preparation was well tolerated and was selected as a preferred preventative strategy by about half the participants. Moonstone is an alternative, over-the-counter therapy for kidney stone prevention.

TJ-17 (Goreisan) mitigates renal fibrosis in a mouse model of folic acid-induced chronic kidney disease

Background and purposeTJ-17 (Goreisan), a traditional Japanese Kampo medicine, has been generally used to treat edema, such as heart failure, due to its diuretic effect. In the present study, we investigate the effects of TJ-17 on chronic kidney disease (CKD). MethodsWe the preventive action of TJ-17 against acute kidney injury (AKI) transition to CKD in vivo using a folic acid (FA)-induced mouse model. Mice were treated with food containing TJ-17 at 48 h after FA intraperitoneal injection (AKI phase). ResultsHistological analysis, as well as renal function and renal injury markers, deteriorated in mice with FA-induced CKD and were ameliorated by TJ-17 treatment. Increased levels of inflammatory cytokines and macrophage infiltration were also alleviated in mice treated with TJ-17. Renal fibrosis, a crucial factor in CKD, was induced by FA administration and inhibited by TJ-17 treatment. Pretreatment with TJ-17 did not exert an inhibitory effect on FA-induced AKI. The increase in urinary volume in FA-induced CKD mice was ameliorated by TJ-17 treatment, with a concurrent correction of reduced aquaporins expression in the kidney. ConclusionTJ-17 may have a novel preventive effect against inflammation, oxidative stress, and fibrosis, contributing to innovation in the treatment of CKD.

Partial vasopressin 1a receptor agonism reduces portal hypertension and hyperaldosteronism and induces a powerful diuretic and natriuretic effect in rats with cirrhosis and ascites

The vasopressin system has emerged as a therapeutic focus for lowering portal hypertension and reducing splanchnic vasodilation in patients with refractory ascites. Clinically available vasopressin agonists are limited by preferential selectivity for V1 receptors that also have steep concentration–response curves with potential risks of excess vasoconstriction and/or complete antidiuretic effects. OCE-205 is a novel, selective, partial V1a receptor agonist with mixed agonist/antagonist activity and no V2 receptor activation at therapeutic doses. We carried out two studies assessing the in vivo effects of OCE-205 in different rat models of cirrhosis and ascites. In a carbon tetrachloride rat cirrhosis model, OCE-205 administration produced a marked reduction in portal hypertension and hyperaldosteronism, along with robust diuretic and natriuretic effects. These effects were accompanied by marked decreases in ascites volume, with three of five animals experiencing total mobilization of ascites. There was no evidence of fluid overload or sodium or water retention, confirming OCE-205′s lack of V2 receptor activity. In a second, corroborative study using a bile duct ligation rat model of ascites, OCE-205 produced significant decreases in ascites volume and body weight and a significant increase in urine volume versus vehicle. Urine sodium excretion increased significantly after the first administration of OCE-205 relative to vehicle; however, repeat administration over 5 days did not lead to hyponatremia. Thus, in separate in vivo models, the mixed agonist/antagonist OCE-205 demonstrated relevant and expected endpoint findings consistent with its known mechanism of action and in vitro pharmacology without apparent unwanted effects or nonspecific toxicities.

Anti-Urolithiatic and Nephroprotective Activity of Quercetin and Betulin in Conjunction with a Bio Enhancer – An in Vivo Study

Background: In the Indian Traditional system of Medicine, the herbal drug Aerva lanata was widely used in the management of urolithiasis. In the present study, a bioenhancer was used to evaluate the potential of constituents quercetin and betulin isolated from the plant A.lanata. Objective: In the present study, the isolated compounds quercetin and betulin from the plant A.lanata were screened for in vivo anti-urolithiasis and nephroprotective activities. Methodology: In the Wistar albino rats, urolithiasis was induced by ethylene glycol (0.75% v/v) to study the anti-urolithiatic activity. The animals were divided into seven groups of 6 animals in each group (n=6). The study period was for 28-day treatment with quercetin and betulin in combination with piperine as bio enhancers in nephrolithiasis induced rats. The Nephroprotective effect was also investigated in Gentamicin induced nephrotoxicity animal model. Cystone (750 mg/kg) was used as a standard. Biochemical parameters such as blood urea nitrogen (BUN), uric acid, and creatinine in the serum were determined. Renal calculi were determined in kidney homogenate and histopathology was also examined. Results: With the test drug treatment, animals showed increased urine volume significantly, also the renal tissue exhibited a reduction in the calculi formation. In the disease control animals, there was an increase in the serum BUN, uric acid, and creatinine significantly. Serum analysis revealed a significant reduction (*p&lt;0.001) in the levels of BUN, uric acid, and creatinine in treated rats. Histopathological studies disclosed an improvement in the anatomical aspect of renal tissue. Conclusion: It was concluded that quercetin and betulin exhibited anti-urolithiatic effect by a reduction in the formation of calculi. The current study provided a rationale for the combination of piperine, quercitin, and betulin.

Feasibility of Mini sipIT Behavioral Intervention to Increase Urine Volume in Patients With Kidney Stones

To determine the feasibility and acceptability of mini sipIT, a context-sensitive reminder system that incorporates a connected water bottle and mobile app with text messaging, for kidney stone patients who have poor adherence to increasing fluid intake for prevention. Patients with a history of kidney stones and urine volume <2L/d participated in a 1-month single-group feasibility trial. Patients used a connected water bottle and received text message reminders when fluid intake goals weren't met. Perceptions of drinking behavior, intervention acceptability, and 24-hour urine volumes were obtained at baseline and 1-month. Patients with a history of kidney stones were enrolled (n = 26, 77% female, age=50.4 ± 14.2years). Over 90% of patients used the bottle or app daily. Most patients perceived that mini sipIT intervention helped them to increase their fluid intake (85%) and reach their fluid intake goals (65%). There was a significant increase in average 24-hour urine volume after the 1-month intervention compared to baseline (2006.5 ± 980.8 mL vs 1352.7 ± 449.9 mL, t (25)= 3.66, P = .001, g= 0.78), with 73% of patients having higher 24-hour urine volumes at the end of the trial. Mini sipIT behavioral intervention and outcome assessments are feasible for patients and may lead to significant increases in 24-hour urine volume. Digital tools in combination with behavioral science may improve adherence to fluid intake recommendations for kidney stone prevention, however, rigorous efficacy trials are necessary.

The gene therapy for corneal pathology with novel nonsense cystinosis mouse lines created by CRISPR Gene Editing

PurposeCystinosis is an autosomal recessive lysosomal storage disease (LSDs) caused by mutations in the gene encoding cystinosin (CTNS) that leads to cystine crystal accumulation in the lysosome that compromises cellular functions resulting in tissue damage and organ failure, especially in kidneys and eyes. However, the underlying molecular mechanism of its pathogenesis remains elusive. Two novel mice lines created via CRISPR are used to examine the pathogenesis of cystinosis in the kidney and cornea and the treatment efficacy of corneal pathology using self-complimentary Adeno-associated viral (scAAV-CTNS) vector. MethodsThe CRISPR technique generated two novel cystinotic mouse lines, Ctnsis1 (an insertional mutation) and Ctnsis2 (a nonsense mutation). Immune histochemistry, renal functions test and HRT2 in vivo confocal microscopy were used to evaluate the age-related renal pathogenesis and treatment efficacy of the scAAV-CTNS virus in corneal pathology. ResultsBoth mutations lead to the production of truncated Ctns proteins. Ctnsis1 and Ctnsis 2 mice exhibit the characteristic of cystinotic corneal crystal phenotype at four-week-old. Treatment with the scAAV-CTNS viral vector decreased the corneal crystals in the treated mice cornea. Ctnsis 1 show renal abnormalities manifested by increased urine volume, reduced urine osmolality, and the loss of response to Desmopressin (dDAVP) at 22-month-old but Ctnsis2 don't manifest renal pathology up to 2 years of age. ConclusionsBoth Ctnsis1 and Ctnsis2 mice exhibit phenotypes resembling human intermediate nephropathic and ocular cystinosis, respectively. scAAV-CTNS viral vectors reduce the corneal cystine crystals and have a great potential as a therapeutic strategy for treating patients suffering from cystinosis.

Diabetes Insipidus Pascaoperasi pada Pasien dengan Reseksi Tumor Kraniofaringioma

Craniopharyngioma is an embryonic malformation in the sella and parasella areas. Craniopharyngioma has high survival rate, although the patient's quality of life is often compromised due to tumor’s location near important anatomical structures such as the optic nerve, optic chiasm, and hypothalamic-pituitary axis. Craniopharyngioma tumor resection can provoke diabetes insipidus. Diabetes insipidus (DI) is characterized by polyuria, dehydration and hypernatremia due to vasopressin or antidiuretic hormone (ADH) deficiency. A 20 years old male patient complained of polyuria, paresthesia in both hands, rapid body growth, and headaches. Brain magnetic resonance imaging (MRI) with contrast revealed cystic mass in the parasella cistern region suggested craniopharyngioma. This patient underwent craniotomy tumor resection under general anesthesia and additional scalp block. Postoperatively the patient experienced an increased urine volume up to 400 ml/hour and fluid replacement was performed with crystalloids Ringerfundin and D5 ¼ NS. The patient suffered DI and vasopressin was continued in the postoperative period until urine output reduced to &lt;2 ml/kg/hour. Perioperative management of craniopharyngioma is controlling intracranial pressure, prevent secondary brain injury and postoperative monitoring in the intensive care unit to manage potential complications such as DI. In this case, patient suffered polyuria and increased plasma sodium levels which was safely treated by administration of vasopressin and rehydration to maintain fluid adequacy and balance of plasma sodium levels

High dietary K+ intake inhibits proximal tubule transport.

The impact of chronic dietary K+ loading on proximal tubule (PT) function was measured using free-flow micropuncture along with measurements of overall kidney function, including urine volume, glomerular filtration rate, and absolute and fractional Na+ and K+ excretion in the rat. Feeding animals a diet with 5% KCl [high K+ (HK)] for 7 days reduced glomerular filtration rate by 29%, increased urine volume by 77%, and increased absolute K+ excretion by 202% compared with rats on a 1% KCl [control K+ (CK)] diet. HK did not change absolute Na+ excretion but significantly increased fraction excretion of Na+ (1.40% vs. 0.64%), indicating that fractional Na+ absorption is reduced by HK. PT reabsorption was assessed using free-flow micropuncture in anesthetized animals. At 80% of the accessible length of the PT, measurements of inulin concentration indicated volume reabsorption of 73% and 54% in CK and HK, respectively. At the same site, fractional PT Na+ reabsorption was 66% in CK animals and 37% in HK animals. Fractional PT K+ reabsorption was 66% in CK and 37% in HK. To assess the role of Na+/H+ exchanger isoform 3 (NHE3) in mediating these changes, we measured NHE3 protein expression in total kidney microsomes as well as surface membranes using Western blots. We found no significant changes in protein in either cell fraction. Expression of the Ser552 phosphorylated form of NHE3 was also similar in CK and HK animals. Reduction in PT transport may facilitate K+ excretion and help balance Na+ excretion by shifting Na+ reabsorption from K+-reabsorbing to K+-secreting nephron segments.NEW & NOTEWORTHY In rats fed a diet rich in K+, proximal tubules reabsorbed less fluid, Na+, and K+ compared with those in animals on a control diet. Glomerular filtration rates also decreased, probably due to glomerulotubular feedback. These reductions may help to maintain balance of the two ions simultaneously by shifting Na+ reabsorption to K+-secreting nephron segments.

#4377 IMPACT OF TOLVAPTAN ON 24H-URINE VOLUME AND OSMOLALITY DURING THE UP-DOSING PHASE IN ADPKD PATIENTS: A SINGLE-CENTER STUDY

Abstract Background and Aims ADPKD is the most prevalent genetic kidney disease. Tolvaptan is the first proven disease-modifying therapy, but is associated with aquaretic side effects, frequently leading to treatment discontinuation. Therefore, identifying factors, which can ameliorate the aquaretic side effects and facilitate therapy is crucial. Previous data reported 24h-osmolar excretion in urine or GFR as the main determinants of urine volume on tolvaptan but included only few patients. This study's objective was to prospectively examine the 24-hour urine volume and urine osmolality during the up-dosing phase of tolvaptan in a cohort with a moderate sample size and different subgroups in order to identify modifiable and non-modifiable factors for urine volume increase. Finally, quality of life (QoL) during tolvaptan treatment was investigated in relation to urine volume since these data are scarce thus far and provide crucial insights into the therapy burden. Method Analysis of 24-h urine collection at baseline and at least once on tolvaptan was carried out for 75 patients (complete cohort). For 35 patients (longitudinal cohort) urine collections were available for baseline and all three tolvaptan doses (45/15 mg, 60/30 mg and 90/30 mg). All patients are participants of the German AD(H)PKD registry. Sodium, protein and potassium intake were calculated from excretion in 24h-urine and QoL was assessed by the Short Form-12 (SF-12) questionnaire. Statistical analyses were computed using R statistical software. A p-value of &amp;lt; 0.05 was regarded as significant. Results The mean age of the patients in the complete cohort was 41.3 ± 10.7 (range 18-64 years) with a mean eGFR of 67.3 ± 27.2 ml/min/1.73m2 and was similar to the longitudinal cohort with a mean age of 41.8 ± 10.1 (23-64 years) and eGFR of 69.4 ± 27.5ml/min/1.73m2. A significant increase (p&amp;lt; 0.0001) in 24-h urine volume (138%) occurred only immediately after therapy initiation with no further significant increase during updosing in the complete and longitudinal cohort. In line with this 24h-urine osmolality decreased (57%) significantly (p&amp;lt; 0.0001) only after beginning of treatment and remained almost unchanged after updosing. Total solutes, protein and sodium intake showed non-significant changes across all doses. There were no significant differences in urine volume between gender, age classes (&amp;lt;45 vs. ≥45 years), or Mayo class when examining the various subgroups. Considering modifiable factors, 24h-urine volume was positively correlated with eGFR on tolvaptan reaching significance on 45/15 mg (p = 0.013) and 90/30 mg (p = 0.027). Patients &amp;lt;45 years and patients with an eGFR ≥ 60 ml/min/1.73m2 experienced a significantly higher relative urine volume increase at the beginning (p = 0.0332 vs. ≥45 years and p = 0.0097 vs eGFR &amp;lt; 60 ml/min/1.73m2) in the complete cohort. In multivariable linear regression analyses containing modifiable and non-modifiable covariates only sodium intake had a significant impact in tolvaptan-naive patients (p = 0.0064), while on tolvaptan age (p = 0.0008) and weight (p = 0.0190) became significant together with sodium intake (p = 0.0008) and potassium intake (p = 0.0040). Across the three tolvaptan doses no significant differences between the number of patients reaching pre-defined osmolality goals (&amp;lt; 250 mosmol/kg for spontaneous urine and &amp;lt; 150 mosmol/kg for 24h-urine) could be detected. Before and after tolvaptan treatment, neither the mental nor physical QoL changed significantly. Conclusion Our study showed that the significant rise in urine volume occurs immediately after therapy initiation with only minor and non-significant increases upon further updosing. Urine osmolality decreases significantly directly after start of tolvaptan and remains constant with most patients achieving adequate suppression of urine osmolality. Patient counseling should consider that younger patients and patients with better eGFR might experience stronger urine volume increase at the beginning and advising to reduce salt and potassium intake can ameliorate aquaretic side effects. Tolvaptan treatment showed no negative impact on QoL but further investigations in larger cohorts are needed.

#4085 POLY(ADP-RIBOSE) POLYMERASE 1 AFFECTS THE VASOPRESSIN-MEDIATED AQP2 EXPRESSION VIA AN INTERACTION WITH BETA-CATENIN

Abstract Background and Aims Poly(ADP-ribosy)lation (PARylation), which is mediated by poly(ADP-ribose) polymerases (PARPs), catalyzes the transfer of ADP-ribose from NAD+ molecules to acceptor proteins, regulates diverse cellular processes. Since PARP1 gene-deficient mice revealed an increase in urine volume, we aimed to examine the role of PARP1, the most abundant type of protein in the PARPs family, in the vasopressin-mediated AQP2 regulation. Method 1) Immunoblotting for PARP1 in mpkCCDc14 cells; 2) Pulldown assay of biotin-conjugated NAD+ and immunoprecipitation (IP) assay using poly(ADP-ribose) (PAR) antibody; 3) qRT-PCR and immunoblotting for AQP2; and 4) Bioinformatics for elucidating PARP1-interacting proteins in kidney collecting duct (CD) cells. Results Immunoblots showed that dDAVP treatment (10−9 M, 2 h, 6 h, 24 h, and 48 h) induced the cleavage of PARP1 (both 89 kDa and 25 kDa) in mpkCCDc14 cells. dDAVP treatment (10−9 M, 24 h) also increased the abundance of total PARylated proteins in biotin-NAD+ pulldown and IP assay of PAR in mpkCCDc14 cells. On the other hand, siRNA-mediated PARP1 knockdown significantly attenuated the dDAVP-induced mRNA and protein abundance, suggesting a role of PARP1 in AQP2 regulation. PARP1 cleavage induced by dDAVP was not changed under PARP1 knockdown, indicating that PARP1 cleavage is unlikely to be involved in AQP2 regulation. In contrast to PARP1 knockdown, PARP1 inhibitor (PJ34) did not reduce the dDAVP-induced AQP2 abundance, despite the significant decrease in the PARylation. The results suggest that dDAVP-regulated AQP2 expression is associated with PARP1 protein per se, but not with PARP1-mediated PARylation. Bioinformatics study revealed that 408 proteins interact with PARP1 in the kidney CD cells. Among them, 49 proteins were mapped on the vasopressin V2 receptor (V2R) signaling pathway. In particular, β-catenin, which is phosphorylated (S552) by dDAVP, was identified as the PARP1-interacting protein mapped on the V2R signaling. Immunoblotting demonstrated that siRNA-mediated knockdown of PARP1 was associated with decreased dDAVP-induced phosphorylation of β-catenin at S552 in mpkCCDc14 cells. Conclusion PARP1 is likely to play a role in vasopressin-mediated AQP2 regulation via the protein interaction with β-catenin rather than PARylation of proteins and/or PARP1 cleavage in the kidney CD cells.