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IScience Jun 2024The kidney is a vital organ responsible for water and sodium metabolism, while the primary function of amiloride is to promote the excretion of water and sodium. We...
The kidney is a vital organ responsible for water and sodium metabolism, while the primary function of amiloride is to promote the excretion of water and sodium. We investigated amiloride enhanced the sunitinib sensitivity in RCC. We found both sunitinib and amiloride displayed cytotoxicity and exerted the synergy effect in RCC cells and arrays. Protein expression profiles were screened via MS/TMT, revealing that FN3K was upregulated in the sunitinib group, and rescued in amiloride and the combination administration. Exogenous FN3K could promote proliferation, invasion and metastasis and decrease the sensitivity of Caki-1 cells to sunitinib, also, exogenous FN3K up-regulated VEGFR2 expression and activated AKT/mTOR signal pathway. More FN3K and VEGFR2 accumulated in R-Caki-1 cells and rescued by amiloride treatment. Co-IP and IF confirmed the interaction between FN3K and VEGFR2. In conclusion, FN3K depletion mediated VEGFR2 disruption promotes amiloride synergized the anti-RCC activity of sunitinib.
PubMed: 38868177
DOI: 10.1016/j.isci.2024.109997 -
Lab on a Chip Jun 2024The volume and composition of airway surface liquid (ASL) is regulated by liquid secretion and absorption across airway epithelia, controlling the pH, solute...
The volume and composition of airway surface liquid (ASL) is regulated by liquid secretion and absorption across airway epithelia, controlling the pH, solute concentration, and biophysical properties of ASL in health and disease. Here, we developed a method integrating explanted tracheal tissue with a micro-machined device (referred to as " trachea-chip") to study the dynamic properties of ASL volume regulation. The trachea-chip allows real-time measurement of ASL transport () with intact airway anatomic structures, environmental control, high-resolution, and enhanced experimental throughput. Applying this technology to freshly excised tissue we observed ASL absorption under basal conditions. The apical application of amiloride, an inhibitor of airway epithelial sodium channels (ENaC), reduced airway liquid absorption. Furthermore, the basolateral addition of NPPB, a Cl channel inhibitor, reduced the basal rate of ASL absorption, implicating a role for basolateral Cl channels in ASL volume regulation. When tissues were treated with apical amiloride and basolateral methacholine, a cholinergic agonist that stimulates secretion from airway submucosal glands, the net airway surface liquid production shifted from absorption to secretion. This trachea-chip provides a new tool to investigate ASL transport dynamics in pulmonary disease states and may aid the development of new therapies targeting ASL regulation.
Topics: Trachea; Amiloride; Animals; Lab-On-A-Chip Devices; Humans; Microfluidic Analytical Techniques; Respiratory Mucosa
PubMed: 38779981
DOI: 10.1039/d4lc00134f -
The American Journal of Case Reports May 2024BACKGROUND Nephrogenic diabetes insipidus (NDI) is a rare renal disorder that can be congenital, and is caused by mutations in either aquaporin 2 or arginine vasopressin...
A Rare Case of Congenital Nephrogenic Diabetes Insipidus Associated with Aquaporin 2 Gene Mutation and Subsequent Acute Lymphoblastic Leukemia: Impact of Steroids on Kidney Function.
BACKGROUND Nephrogenic diabetes insipidus (NDI) is a rare renal disorder that can be congenital, and is caused by mutations in either aquaporin 2 or arginine vasopressin receptor 2, or it can be secondary to kidney disease or electrolyte imbalance. The clinical signs of NDI include polyuria, compensatory polydipsia, hypernatremic dehydration, and growth retardation without prompt treatment. In this report, we present the case of a patient with congenital NDI who was later diagnosed with acute lymphoblastic leukemia (ALL). With dexamethasone treatment, he had uncontrolled polyuria and polydipsia. Our aim was to concentrate on the impact of steroids on the kidneys. CASE REPORT Our patient presented at the age of 9 months with signs of severe dehydration that were associated with polyuria. His laboratory examinations revealed hypernatremia and decreased urine osmolality. He was diagnosed with NDI and his exome sequence revealed a homozygous mutation at the nucleotide position AQP2 NM_000486.6: c.374C>T (p.Thr125Met). He was treated with hydrochlorothiazide and amiloride. Then, at age 19 months, he presented with gastroenteritis and a complete blood count (CBC) showed high white blood cell count and blast cells. He was diagnosed with (ALL) and began receiving chemotherapy, during which again developed polydipsia and polyuria, which could not be controlled with an increased dosage of hydrochlorothiazide. CONCLUSIONS We report a rare case of NDI caused by a missense mutation in the aquaporin 2 gene. One year later, the child developed ALL, and treatment with dexamethasone led to an uncompensated state of polydipsia and polyuria.
Topics: Humans; Male; Diabetes Insipidus, Nephrogenic; Aquaporin 2; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Infant; Dexamethasone; Mutation; Glucocorticoids
PubMed: 38769718
DOI: 10.12659/AJCR.943597 -
International Journal of Molecular... Mar 2024Acid-sensing ion channels (ASICs) play a key role in the perception and response to extracellular acidification changes. These proton-gated cation channels are critical...
Acid-sensing ion channels (ASICs) play a key role in the perception and response to extracellular acidification changes. These proton-gated cation channels are critical for neuronal functions, like learning and memory, fear, mechanosensation and internal adjustments like synaptic plasticity. Moreover, they play a key role in neuronal degeneration, ischemic neuronal injury, seizure termination, pain-sensing, etc. Functional ASICs are homo or heterotrimers formed with (ASIC1-ASIC3) homologous subunits. ASIC1a, a major ASIC isoform in the central nervous system (CNS), possesses an acidic pocket in the extracellular region, which is a key regulator of channel gating. Growing data suggest that ASIC1a channels are a potential therapeutic target for treating a variety of neurological disorders, including stroke, epilepsy and pain. Many studies were aimed at identifying allosteric modulators of ASIC channels. However, the regulation of ASICs remains poorly understood. Using all available crystal structures, which correspond to different functional states of ASIC1, and a molecular dynamics simulation (MD) protocol, we analyzed the process of channel inactivation. Then we applied a molecular docking procedure to predict the protein conformation suitable for the amiloride binding. To confirm the effect of its sole active blocker against the ASIC1 state transition route we studied the complex with another MD simulation run. Further experiments evaluated various compounds in the Enamine library that emerge with a detectable ASIC inhibitory activity. We performed a detailed analysis of the structural basis of ASIC1a inhibition by amiloride, using a combination of in silico approaches to visualize its interaction with the ion pore in the open state. An artificial activation (otherwise, expansion of the central pore) causes a complex modification of the channel structure, namely its transmembrane domain. The output protein conformations were used as a set of docking models, suitable for a high-throughput virtual screening of the Enamine chemical library. The outcome of the virtual screening was confirmed by electrophysiological assays with the best results shown for three hit compounds.
Topics: Humans; Benzamidines; Amiloride; Molecular Docking Simulation; Acid Sensing Ion Channels; Pain
PubMed: 38612396
DOI: 10.3390/ijms25073584 -
Bone & Joint Research Apr 2024Osteosarcoma is the most common primary bone malignancy among children and adolescents. We investigated whether benzamil, an amiloride analogue and sodium-calcium...
AIMS
Osteosarcoma is the most common primary bone malignancy among children and adolescents. We investigated whether benzamil, an amiloride analogue and sodium-calcium exchange blocker, may exhibit therapeutic potential for osteosarcoma in vitro.
METHODS
MG63 and U2OS cells were treated with benzamil for 24 hours. Cell viability was evaluated with the MTS/PMS assay, colony formation assay, and flow cytometry (forward/side scatter). Chromosome condensation, the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay, cleavage of poly-ADP ribose polymerase (PARP) and caspase-7, and FITC annexin V/PI double staining were monitored as indicators of apoptosis. Intracellular calcium was detected by flow cytometry with Fluo-4 AM. The phosphorylation and activation of focal adhesion kinase (FAK) and signal transducer and activator of transcription 3 (STAT3) were measured by western blot. The expression levels of X-linked inhibitor of apoptosis protein (XIAP), B-cell lymphoma 2 (Bcl-2), B-cell lymphoma-extra large (Bcl-xL), SOD1, and SOD2 were also assessed by western blot. Mitochondrial status was assessed with tetramethylrhodamine, ethyl ester (TMRE), and intracellular adenosine triphosphate (ATP) was measured with BioTracker ATP-Red Live Cell Dye. Total cellular integrin levels were evaluated by western blot, and the expression of cell surface integrins was assessed using fluorescent-labelled antibodies and flow cytometry.
RESULTS
Benzamil suppressed growth of osteosarcoma cells by inducing apoptosis. Benzamil reduced the expression of cell surface integrins α5, αV, and β1 in MG63 cells, while it only reduced the expression of αV in U2OS cells. Benzamil suppressed the phosphorylation and activation of FAK and STAT3. In addition, mitochondrial function and ATP production were compromised by benzamil. The levels of anti-apoptotic proteins XIAP, Bcl-2, and Bcl-xL were reduced by benzamil. Correspondingly, benzamil potentiated cisplatin- and methotrexate-induced apoptosis in osteosarcoma cells.
CONCLUSION
Benzamil exerts anti-osteosarcoma activity by inducing apoptosis. In terms of mechanism, benzamil appears to inhibit integrin/FAK/STAT3 signalling, which triggers mitochondrial dysfunction and ATP depletion.
PubMed: 38569602
DOI: 10.1302/2046-3758.134.BJR-2023-0289.R1 -
Experimental Physiology May 2024It has been proposed that diuretics can improve renal tissue oxygenation through inhibition of tubular sodium reabsorption and reduced metabolic demand. However, the...
It has been proposed that diuretics can improve renal tissue oxygenation through inhibition of tubular sodium reabsorption and reduced metabolic demand. However, the impact of clinically used diuretic drugs on the renal cortical and medullary microcirculation is unclear. Therefore, we examined the effects of three commonly used diuretics, at clinically relevant doses, on renal cortical and medullary perfusion and oxygenation in non-anaesthetised healthy sheep. Merino ewes received acetazolamide (250 mg; n = 9), furosemide (20 mg; n = 10) or amiloride (10 mg; n = 7) intravenously. Systemic and renal haemodynamics, renal cortical and medullary tissue perfusion and , and renal function were then monitored for up to 8 h post-treatment. The peak diuretic response occurred 2 h (99.4 ± 14.8 mL/h) after acetazolamide, at which stage cortical and medullary tissue perfusion and were not significantly different from their baseline levels. The peak diuretic response to furosemide occurred at 1 h (196.5 ± 12.3 mL/h) post-treatment but there were no significant changes in cortical and medullary tissue oxygenation during this period. However, cortical tissue fell from 40.1 ± 3.8 mmHg at baseline to 17.2 ± 4.4 mmHg at 3 h and to 20.5 ± 5.3 mmHg at 6 h after furosemide administration. Amiloride did not produce a diuretic response and was not associated with significant changes in cortical or medullary tissue oxygenation. In conclusion, clinically relevant doses of diuretic agents did not improve regional renal tissue oxygenation in healthy animals during the 8 h experimentation period. On the contrary, rebound renal cortical hypoxia may develop after dissipation of furosemide-induced diuresis.
Topics: Animals; Furosemide; Acetazolamide; Amiloride; Diuretics; Sheep; Female; Kidney Cortex; Kidney Medulla; Oxygen; Hemodynamics; Oxygen Consumption
PubMed: 38551893
DOI: 10.1113/EP091479 -
Therapeutic Advances in Chronic Disease 2024The effectiveness and side effects between different medical treatments in patients with primary hyperaldosteronism have not been systematically studied.
BACKGROUND
The effectiveness and side effects between different medical treatments in patients with primary hyperaldosteronism have not been systematically studied.
OBJECTIVE
To analyze the efficacy between different mineralocorticoid receptor antagonists (MRAs) and epithelial sodium channel (ENaC) inhibitors in a network meta-analysis (NMA) framework, while also evaluating adverse events.
DESIGN
Systematic review and NMA.
DATA SOURCES AND METHODS
The systematic review and NMA was reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, MEDLINE, the Cochrane library, and Excerpta Medica database (EMBASE) were searched for randomized controlled trials (RCTs) involving adult patients with primary hyperaldosteronism until 23 June 2023. Studies that compared the efficacy and side effects of different medical treatments of primary hyperaldosteronism were included. The primary outcomes included the effect on blood pressure, serum potassium, and major adverse cardiovascular events. The secondary outcomes were adverse events related to MRAs (hyperkalemia and gynecomastia). Frequentist NMA and pairwise meta-analysis were conducted.
RESULTS
A total of 5 RCTs comprising 392 participants were included. Eplerenone, esaxerenone, and amiloride were compared to spironolactone and demonstrated comparable effect on the reduction of systolic blood pressure. In comparison to spironolactone, eplerenone exhibited a less pronounced effect on reducing diastolic blood pressure [-4.63 mmHg; 95% confidence interval (CI): -8.87 to -0.40 mmHg] and correcting serum potassium (-0.2 mg/dL; 95% CI: -0.37 to -0.03 mg/dL). Spironolactone presented a higher risk of gynecomastia compared with eplerenone (relative risk: 4.69; 95% CI: 3.58-6.14).
CONCLUSION
The present NMA indicated that the blood pressure reduction and potassium-correcting effects of the three MRAs may demonstrate marginal differences, with confidence levels in the evidence being very low. Therefore, further research is needed to explore the efficacy of these MRAs, especially regarding their impact on mortality and cardiovascular outcomes.
TRIAL REGISTRATION
PROSPERO (CRD: 42023446811).
PubMed: 38511069
DOI: 10.1177/20406223241239775 -
International Journal of Surgery Case... Apr 2024Heterotopic ossification is forming a new bone in tissues that do not normally ossify. HO was first reported in 1901 by Askanazy and Lubarsh in a case report study. The...
INTRODUCTION AND IMPORTANCE
Heterotopic ossification is forming a new bone in tissues that do not normally ossify. HO was first reported in 1901 by Askanazy and Lubarsh in a case report study. The range of HO is wide from minute foci to large clinically significant ossification. The incidence of HO in abdominal scars is extremely low.
CASE PRESENTATION
We present an 84-year-old man referred to our hospital after an unsuccessful elective colostomy reversal in a local hospital. The colostomy was made for fecal diversion after sigmoidectomy due to treatment of sigmoid volvulus about three months ago. The patient had a past medical history of hypertension for 8 years under treatment of amiloride.
CLINICAL DISCUSSION
In general appearance, the patient was not ill or toxic. Vital signs were normal. Postoperatively Patient did not defecate. In his physical examination was not found abdominal tenderness or rebound tenderness. The patient underwent laparotomy which revealed significant retroperitoneal adhesion and colostomy was reversed. Accidentally was found a dense structure with bone-like consistency in the abdominal wall close to the scar was resected. The specimen Pathologic examination showed metaplastic bone deposition with mature bone trabeculae and heterotopic ossification was confirmed.
CONCLUSION
We report a rare case of HO that was identified at the abdominal wall. Heterotopic ossification can lead to serious complications. However, in symptomatic patients, surgical excision is an acceptable treatment, unlike in asymptomatic patients.
PubMed: 38460290
DOI: 10.1016/j.ijscr.2024.109469