A Double-Blind, Randomized, Placebo-Controlled Trial of Bumetanide in Parkinson's Disease.

BACKGROUND: Acting on the main target of dopaminergic cells, the striatal γ-aminobutyric acid (GABA)-ergic cells, might be a new way to treat persons with Parkinson's disease (PD). OBJECTIVE: The objective of this study was to assess the efficacy of bumetanide, an Na-K-Cl cotransporter (NKCC1) inhibitor, to improve motor symptoms in PD. METHODS: This was a 4-month double-blind, randomized, parallel-group, placebo-controlled trial of 1.75 to 3 mg/day bumetanide as an adjunct to levodopa in 44 participants with PD and motor fluctuations. RESULTS: Compared to the baseline, the mean change in OFF Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III score after 4 months of treatment (primary endpoint) did not improve significantly compared with placebo. No changes between participants treated with bumetanide and those treated with placebo were observed for most other outcome measures. Despite no relevant safety signals, bumetanide was poorly tolerated. CONCLUSIONS: There was no evidence in this study that bumetanide has efficacy in improving motor symptoms of PD. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Crossover randomized controlled trial of bumetanide to rescue an attack of exercise induced hand weakness in hypokalaemic periodic paralysis.

The aim of this study was to establish whether bumetanide can abort an acute attack of weakness in patients with HypoPP. This was a randomised, double-blind, cross-over, placebo-controlled phase II clinical trial. Focal attack of weakness was induced by isometric exercise of ADM followed by rest (McManis protocol). Participants had two study visits and received either placebo or 2 mg bumetanide at attack onset (defined as 40 % decrement in the abductor digiti minimi CMAP amplitude from peak). CMAP measurements assessed attack severity and duration. Nine participants completed both visits. CMAP percentage of peak amplitudes in the bumetanide (40.6 %) versus placebo (34.9 %) group at 1hr following treatment did not differ significantly (estimated effect difference 5.9 % (95 % CI: (-5.7 %; 17.5 %), p = 0.27, primary outcome). CMAP amplitudes assessed by the area under the curve for early (0-2hr post-treatment) and late (2-4 h post-treatment) efficacy were not statistically different between bumetanide and placebo (early effect estimate 0.043, p = 0.3; late effect estimate 0.085, p = 0.1). Two participants recovered from the attack following bumetanide intake; none recovered following placebo. Bumetanide was well tolerated but not efficacious to rescue a focal attack in an immobilised hand in the majority of patients, although data supports further studies of this agent.

Bumetanide, a Diuretic That Can Help Children with Autism Spectrum Disorder.

BACKGROUND: Autism Spectrum Disorder (ASD) is a common child neurodevelopmental disorder, whose pathogenesis is not completely understood. Until now, there is no proven treatment for the core symptoms of ASD. However, some evidence indicates a crucial link between this disorder and GABAergic signals which are altered in ASD. Bumetanide is a diuretic that reduces chloride, shifts gamma-amino-butyric acid (GABA) from excitation to inhibition, and may play a significant role in the treatment of ASD. OBJECTIVE: The objective of this study is to assess the safety and efficacy of bumetanide as a treatment for ASD. METHODS: Eighty children, aged 3-12 years, with ASD diagnosed by Childhood Autism Rating Scale (CARS), ⩾ 30 were included in this double-blind, randomized, and controlled study. Group 1 received Bumetanide, Group 2 received a placebo for 6 months. Follow-up by CARS rating scale was performed before and after 1, 3, and 6 months of treatment. RESULTS: The use of bumetanide in group 1 improved the core symptoms of ASD in a shorter time with minimal and tolerable adverse effects. There was a statistically significant decrease in CARS and most of its fifteen items in group 1 versus group 2 after 6 months of treatment (p-value <0.001). CONCLUSION: Bumetanide has an important role in the treatment of core symptoms of ASD.

Comparative Effect of Loop Diuretic Prescription on Mortality and Heart Failure Readmission.

Loop diuretics are a standard pharmacologic therapy in heart failure (HF) management. Although furosemide is most frequently used, torsemide and bumetanide are increasingly prescribed in clinical practice, possibly because of superior bioavailability. Few real-world comparative effectiveness studies have examined outcomes across all 3 loop diuretics. The study goal was to compare the effects of loop diuretic prescribing at HF hospitalization discharge on mortality and HF readmission. We identified patients in Medicare claims data initiating furosemide, torsemide, or bumetanide after an index HF hospitalization from 2007 to 2017. We estimated 6-month risks of all-cause mortality and a composite outcome (HF readmission or all-cause mortality) using inverse probability of treatment weighting to adjust for relevant confounders. We identified 62,632 furosemide, 1,720 torsemide, and 2,389 bumetanide initiators. The 6-month adjusted all-cause mortality risk was lowest for torsemide (13.2%), followed by furosemide (14.5%) and bumetanide (15.6%). The 6-month composite outcome risk was 21.4% for torsemide, 24.7% for furosemide, and 24.9% for bumetanide. Compared with furosemide, the 6-month all-cause mortality risk was 1.3% (95% confidence interval [CI]: -3.7, 1.0) lower for torsemide and 1.0% (95% CI: -1.2, 3.2) higher for bumetanide, and the 6-month composite outcome risk was 3.3% (95% CI: -6.3, -0.3) lower for torsemide and 0.2% (95% CI: -2.5, 2.9) higher for bumetanide. In conclusion, the findings suggested that the first prescribed loop diuretic following HF hospitalization is associated with clinically important differences in morbidity in older patients receiving torsemide, bumetanide, or furosemide. These differences were consistent for the effect of all-cause mortality alone, but were not statistically significant.

Astrocytic NKCC1 inhibits seizures by buffering Cl- and antagonizing neuronal NKCC1 at GABAergic synapses.

OBJECTIVE: A pathological excitatory action of the major inhibitory neurotransmitter γ-aminobutyric acid (GABA) has been observed in epilepsy. Blocking the Cl- importer NKCC1 with bumetanide is expected to reduce the neuronal intracellular Cl- concentration ([Cl- ]i ) and thereby attenuate the excitatory GABA response. Accordingly, several clinical trials of bumetanide for epilepsy were conducted. Although NKCC1 is expressed in both neurons and glial cells, an involvement of glial NKCC1 in seizures has not yet been reported. Astrocytes maintain high [Cl- ]i with NKCC1, and this gradient promotes Cl- efflux via the astrocytic GABAA receptor (GABAA R). This Cl- efflux buffers the synaptic cleft Cl- concentration to maintain the postsynaptic Cl- gradient during intense firing of GABAergic neurons, thereby sustaining its inhibitory action during seizure. In this study, we investigated the function of astrocytic NKCC1 in modulating the postsynaptic action of GABA in acute seizure models. METHODS: We used the astrocyte-specific conditional NKCC1 knockout (AstroNKCC1KO) mice. The seizurelike events (SLEs) in CA1 pyramidal neurons were triggered by tetanic stimulation of stratum radiatum in acute hippocampus slices. The SLE underlying GABAA R-mediated depolarization was evaluated by applying the GABAA R antagonist bicuculline. The pilocarpine-induced seizure in vivo was monitored in adult mice by the Racine scale. The SLE duration and tetanus stimulation intensity threshold and seizure behavior in AstroNKCC1KO mice and wild-type (WT) mice were compared. RESULTS: The AstroNKCC1KO mice were prone to seizures with lower threshold and longer duration of SLEs and larger GABAA R-mediated depolarization underlying the SLEs, accompanied by higher Racine-scored seizures. Bumetanide reduced these indicators of seizure in AstroNKCC1KO mice (which still express neuronal NKCC1), but not in the WT, both in vitro and in vivo. SIGNIFICANCE: Astrocytic NKCC1 inhibits GABA-mediated excitatory action during seizures, whereas neuronal NKCC1 has the converse effect, suggesting opposing actions of bumetanide on these cells.

Bumetanide Attenuates Cognitive Deficits and Brain Damage in Rats Subjected to Hypoxia-Ischemia at Two Time Points of the Early Postnatal Period.

Neonatal hypoxia-ischemia (HI) is one of the main causes of tissue damage, cell death, and imbalance between neuronal excitation and inhibition and synaptic loss in newborns. GABA, the major inhibitory neurotransmitter of the central nervous system (CNS) in adults, is excitatory at the onset of neurodevelopment and its action depends on the chloride (Cl-) cotransporters NKCC1 (imports Cl-) and KCC2 (exports Cl-) expression. Under basal conditions, the NKCC1/KCC2 ratio decreases over neurodevelopment. Thus, changes in this ratio caused by HI may be related to neurological disorders. The present study evaluated the effects of bumetanide (NKCC cotransporters inhibitor) on HI impairments in two neurodevelopmental periods. Male Wistar rat pups, 3 (PND3) and 11 (PND11) days old, were submitted to the Rice-Vannucci model. Animals were divided into 3 groups: SHAM, HI-SAL, and HI-BUM, considering each age. Bumetanide was administered intraperitoneally at 1, 24, 48, and 72 h after HI. NKCC1, KCC2, PSD-95, and synaptophysin proteins were analyzed after the last injection by western blot. Negative geotaxis, righting reflex, open field, object recognition test, and Morris water maze task were performed to assess neurological reflexes, locomotion, and memory function. Tissue atrophy and cell death were evaluated by histology. Bumetanide prevented neurodevelopmental delay, hyperactivity, and declarative and spatial memory deficits. Furthermore, bumetanide reversed HI-induced brain tissue damage, reduced neuronal death and controlled GABAergic tone, maintained the NKCC1/KCC2 ratio, and synaptogenesis close to normality. Thereby, bumetanide appears to play an important therapeutic role in the CNS, protecting the animals against HI damage and improving functional performance.

Bumetanide potentiates the anti-seizure and disease-modifying effects of midazolam in a noninvasive rat model of term birth asphyxia.

Birth asphyxia and the resulting hypoxic-ischemic encephalopathy (HIE) are highly associated with perinatal and neonatal death, neonatal seizures, and an adverse later-life outcome. Currently used drugs, including phenobarbital and midazolam, have limited efficacy to suppress neonatal seizures. There is a medical need to develop new therapies that not only suppress neonatal seizures but also prevent later-life consequences. We have previously shown that the loop diuretic bumetanide does not potentiate the effects of phenobarbital in a rat model of birth asphyxia. Here we compared the effects of bumetanide (0.3 or 10 mg/kg i.p.), midazolam (1 mg/kg i.p.), and a combination of bumetanide and midazolam on neonatal seizures and later-life outcomes in this model. While bumetanide at either dose was ineffective when administered alone, the higher dose of bumetanide markedly potentiated midazolam's effect on neonatal seizures. Median bumetanide brain levels (0.47-0.53 µM) obtained with the higher dose were in the range known to inhibit the Na-K-Cl-cotransporter NKCC1 but it remains to be determined whether brain NKCC1 inhibition was underlying the potentiation of midazolam. When behavioral and cognitive alterations were examined over three months after asphyxia, treatment with the bumetanide/midazolam combination, but not with bumetanide or midazolam alone, prevented impairment of learning and memory. Furthermore, the combination prevented the loss of neurons in the dentate hilus and aberrant mossy fiber sprouting in the CA3a area of the hippocampus. The molecular mechanisms that explain that bumetanide potentiates midazolam but not phenobarbital in the rat model of birth asphyxia remain to be determined.

Prediction of Behavioral Improvement Through Resting-State Electroencephalography and Clinical Severity in a Randomized Controlled Trial Testing Bumetanide in Autism Spectrum Disorder.

BACKGROUND: Mechanism-based treatments such as bumetanide are being repurposed for autism spectrum disorder. We recently reported beneficial effects on repetitive behavioral symptoms that might be related to regulating excitation-inhibition (E/I) balance in the brain. Here, we tested the neurophysiological effects of bumetanide and the relationship to clinical outcome variability and investigated the potential for machine learning-based predictions of meaningful clinical improvement. METHODS: Using modified linear mixed models applied to intention-to-treat population, we analyzed E/I-sensitive electroencephalography (EEG) measures before and after 91 days of treatment in the double-blind, randomized, placebo-controlled Bumetanide in Autism Medication and Biomarker study. Resting-state EEG of 82 subjects out of 92 participants (7-15 years) were available. Alpha frequency band absolute and relative power, central frequency, long-range temporal correlations, and functional E/I ratio treatment effects were related to the Repetitive Behavior Scale-Revised (RBS-R) and the Social Responsiveness Scale 2 as clinical outcomes. RESULTS: We observed superior bumetanide effects on EEG, reflected in increased absolute and relative alpha power and functional E/I ratio and in decreased central frequency. Associations between EEG and clinical outcome change were restricted to subgroups with medium to high RBS-R improvement. Using machine learning, medium and high RBS-R improvement could be predicted by baseline RBS-R score and EEG measures with 80% and 92% accuracy, respectively. CONCLUSIONS: Bumetanide exerts neurophysiological effects related to clinical changes in more responsive subsets, in whom prediction of improvement was feasible through EEG and clinical measures.

The loop diuretic torasemide but not azosemide potentiates the anti-seizure and disease-modifying effects of midazolam in a rat model of birth asphyxia.

Loop diuretics such as furosemide and bumetanide, which act by inhibiting the Na-K-2Cl cotransporter NKCC2 at the thick ascending limb of the loop of Henle, have been shown to exert anti-seizure effects. However, the exact mechanism of this effect is not known. For bumetanide, it has been suggested that inhibition of the NKCC isoform NKCC1 in the membrane of brain neurons may be involved; however, NKCC1 is expressed by virtually all cell types in the brain, which makes any specific targeting of neuronal NKCC1 by bumetanide impossible. In addition, bumetanide only poorly penetrates the brain. We have previously shown that loop diuretics azosemide and torasemide also potently inhibit NKCC1. In contrast to bumetanide and furosemide, azosemide and torasemide lack a carboxylic group, which should allow them to better penetrate through biomembranes by passive diffusion. Because of the urgent medical need to develop new treatments for neonatal seizures and their adverse outcome, we evaluated the effects of azosemide and torasemide, administered alone or in combination with phenobarbital or midazolam, in a rat model of birth asphyxia and neonatal seizures. Neither diuretic suppressed the seizures when administered alone but torasemide potentiated the anti-seizure effect of midazolam. Brain levels of torasemide were below those needed to inhibit NKCC1. In addition to suppressing seizures, the combination of torasemide and midazolam, but not midazolam alone, prevented the cognitive impairment of the post-asphyxial rats at 3 months after asphyxia. Furthermore, aberrant mossy fiber sprouting in the hippocampus was more effectively prevented by the combination. We assume that either an effect on NKCC1 at the blood-brain barrier and/or cells in the periphery or the NKCC2-mediated diuretic effect of torasemide are involved in the present findings. Our data suggest that torasemide may be a useful option for improving the treatment of neonatal seizures and their adverse outcome.

Effect of the combination of bumetanide plus chlorthalidone on hypertension and volume overload in patients with chronic kidney disease stage 4-5 KDIGO without renal replacement therapy: a double-blind randomized HEBE-CKD trial.

BACKGROUND: The co-administration of loop diuretics with thiazide diuretics is a therapeutic strategy in patients with hypertension and volume overload. The aim of this study was to assess the efficacy and safety of treatment with bumetanide plus chlorthalidone in patients with chronic kidney disease (CKD) stage 4-5 KDIGO. METHODS: A double-blind randomized study was conducted. Patients were randomized into two groups: bumetanide plus chlorthalidone group (intervention) and the bumetanide plus placebo group (control) to evaluate differences in TBW, ECW and ECW/TBW between baseline and 30 Days of follow-up. Volume overload was defined as 'bioelectrical impedance analysis as fluid volume above the 90th percentile of a presumed healthy reference population. The study's registration number was NCT03923933. RESULTS: Thirty-two patients with a mean age of 57.2 ± 9.34 years and a median estimated glomerular filtration rate (eGFR) of 16.7 ml/min/1.73 m2 (2.2-29) were included. There was decreased volume overload in the liters of total body water (TBW) on Day 7 (intervention: -2.5 vs. control: -0.59, p = 0.003) and Day 30 (intervention: -5.3 vs. control: -0.07, p = 0.016); and in liters of extracellular water (ECW) on Day 7 (intervention: -1.58 vs. control: -0.43, p < 0.001) and Day 30 (intervention: -3.05 vs. control: -0.15, p < 0.000). There was also a decrease in systolic blood pressure on Day 7 (intervention: -18 vs. control: -7.5, p = 0.073) and Day 30 (intervention: -26.1 vs. control: -10, p = 0.028) and in diastolic blood pressure on Day 7 (intervention: -8.5 vs. control: -2.25, p = 0.059) and Day 30 (intervention: -13.5 vs. control: -3.4, p = 0.018). CONCLUSION: In CKD stage 4-5 KDIGO without renal replacement therapy, bumetanide in combination with chlorthalidone is more effective in treating volume overload and hypertension than bumetanide with placebo.

A Wholistic View of How Bumetanide Attenuates Autism Spectrum Disorders.

The specific NKCC1 cotransporter antagonist, bumetanide, attenuates the severity of Autism Spectrum Disorders (ASD), and many neurodevelopmental or neurodegenerative disorders in animal models and clinical trials. However, the pervasive expression of NKCC1 in many cell types throughout the body is thought to challenge the therapeutic efficacy of bumetanide. However, many peripheral functions, including intestinal, metabolic, or vascular, etc., are perturbed in brain disorders contributing to the neurological sequels. Alterations of these functions also increase the incidence of the disorder suggesting complex bidirectional links with the clinical manifestations. We suggest that a more holistic view of ASD and other disorders is warranted to account for the multiple sites impacted by the original intra-uterine insult. From this perspective, large-spectrum active repositioned drugs that act centrally and peripherally might constitute a useful approach to treating these disorders.

Single-case experimental designs for bumetanide across neurodevelopmental disorders: BUDDI protocol.

BACKGROUND: Bumetanide is a selective NKCC1 chloride importer antagonist which is being repurposed as a mechanism-based treatment for neurodevelopmental disorders (NDDs). Due to their specific actions, these kinds of interventions will only be effective in particular subsets of patients. To anticipate stratified application, we recently completed three bumetanide trials each focusing on different stratification strategies with the additional objective of deriving the most optimal endpoints. Here we publish the protocol of the post-trial access combined cohort study to confirm previous effects and stratification strategies in the trial cohorts and in new participants. METHOD/DESIGN: Participants of the three previous cohorts and a new cohort will be subjected to 6 months bumetanide treatment using multiple baseline Single Case Experimental Designs. The primary outcome is the change, relative to baseline, in a set of patient reported outcome measures focused on direct and indirect effects of sensory processing difficulties. Secondary outcome measures include the conventional questionnaires 'social responsiveness scale', 'repetitive behavior scale', 'sensory profile' and 'aberrant behavior scale'. Resting-state EEG measurements will be performed at several time-points including at Tmax after the first administration. Assessment of cognitive endpoints will be conducted using the novel Emma Tool box, an in-house designed battery of computerized tests to measure neurocognitive functions in children. DISCUSSION: This study aims to replicate previously shown effects of bumetanide in NDD subpopulations, validate a recently proposed treatment prediction effect methodology and refine endpoint measurements. TRIAL REGISTRATION: EudraCT: 2020-002196-35, registered 16 November 2020, https://www.clinicaltrialsregister.eu/ctr-search/trial/2020-002196-35/NL.

The immuno-behavioural covariation associated with the treatment response to bumetanide in young children with autism spectrum disorder.

Bumetanide, a drug being studied in autism spectrum disorder (ASD) may act to restore gamma-aminobutyric acid (GABA) function, which may be modulated by the immune system. However, the interaction between bumetanide and the immune system remains unclear. Seventy-nine children with ASD were analysed from a longitudinal sample for a 3-month treatment of bumetanide. The covariation between symptom improvements and cytokine changes was calculated and validated by sparse canonical correlation analysis. Response patterns to bumetanide were revealed by clustering analysis. Five classifiers were used to test whether including the baseline information of cytokines could improve the prediction of the response patterns using an independent test sample. An immuno-behavioural covariation was identified between symptom improvements in the Childhood Autism Rating Scale (CARS) and the cytokine changes among interferon (IFN)-γ, monokine induced by gamma interferon and IFN-α2. Using this covariation, three groups with distinct response patterns to bumetanide were detected, including the best (21.5%, n = 17; Hedge's g of improvement in CARS = 2.16), the least (22.8%, n = 18; g = 1.02) and the medium (55.7%, n = 44; g = 1.42) responding groups. Including the cytokine levels significantly improved the prediction of the best responding group before treatment (the best area under the curve, AUC = 0.832) compared with the model without the cytokine levels (95% confidence interval of the improvement in AUC was [0.287, 0.319]). Cytokine measurements can help in identifying possible responders to bumetanide in ASD children, suggesting that immune responses may interact with the mechanism of action of bumetanide to enhance the GABA function in ASD.

Nanoformulated Bumetanide Ameliorates Social Deficiency in BTBR Mice Model of Autism Spectrum Disorder.

Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder with few medication options. Bumetanide, an FDA-approved diuretic, has been proposed as a viable candidate to treat core symptoms of ASD, however, neither the brain region related to its effect nor the cell-specific mechanism(s) is clear. The availability of nanoparticles provides a viable way to identify pharmacological mechanisms for use in ASD. Here, we found that treatment with bumetanide, in a systemic and medial prefrontal cortex (mPFC) region-specific way, attenuated social deficits in BTBR mice. Furthermore, using poly (ethylene glycol)-poly(l-lactide) (PEG-PLA) nanoparticles [NP(bumetanide)], we showed that the administration of NP(bumetanide) in a mPFC region-specific way also alleviated the social deficits of BTBR mice. Mechanistically, the behavioral effect of NP(bumetanide) was dependent on selective microglia-specific targeting in the mPFC. Pharmacological depletion of microglia significantly reduced the effect of nanoencapsulation and depletion of microglia alone did not improve the social deficits in BTBR mice. These findings suggest the potential therapeutic capabilities of nanotechnology for ASD, as well as the relevant link between bumetanide and immune cells.

Clarifications regarding bumetanide for neonatal seizures.

A recent Phase II randomized, controlled trial of bumetanide as an adjunctive treatment for neonatal seizures showed a robust efficacy signal and no evidence of toxicity. Concerns regarding bumetanide as an adjunctive anticonvulsant are addressed here. An adequately powered multi-institutional trial is needed to accurately determine efficacy.

Bumetanide for neonatal seizures: No light in the pharmacokinetic/dynamic tunnel.

In his editorial, Kevin Staley criticizes our recent work demonstrating the lack of effect of bumetanide in a novel model of neonatal seizures. The main points in our response are that (1) our work is on an asphyxia model, not one on "hypercarbia only"; (2) clinically relevant parenteral doses of bumetanide applied in vivo lead to concentrations in the brain parenchyma that are at least an order of magnitude lower than what would be sufficient to exert any direct effect-even a transient one-on neuronal functions, including neonatal seizures; and (3) moreover, bumetanide's molecular target in the brain is the Na-K-2Cl cotransporter NKCC1, which has vital functions in neurons, astrocytes, and oligodendrocytes as well as microglia. This would make it impossible even for highly brain-permeant NKCC1 blockers to specifically target depolarizing and excitatory actions of γ-aminobutyric acid in principal neurons of the brain, which is postulated as the rationale of clinical trials on neonatal seizures.

The GABA Polarity Shift and Bumetanide Treatment: Making Sense Requires Unbiased and Undogmatic Analysis.

GABA depolarizes and often excites immature neurons in all animal species and brain structures investigated due to a developmentally regulated reduction in intracellular chloride concentration ([Cl-]i) levels. The control of [Cl-]i levels is mediated by the chloride cotransporters NKCC1 and KCC2, the former usually importing chloride and the latter exporting it. The GABA polarity shift has been extensively validated in several experimental conditions using often the NKCC1 chloride importer antagonist bumetanide. In spite of an intrinsic heterogeneity, this shift is abolished in many experimental conditions associated with developmental disorders including autism, Rett syndrome, fragile X syndrome, or maternal immune activation. Using bumetanide, an EMA- and FDA-approved agent, many clinical trials have shown promising results with the expected side effects. Kaila et al. have repeatedly challenged these experimental and clinical observations. Here, we reply to the recent reviews by Kaila et al. stressing that the GABA polarity shift is solidly accepted by the scientific community as a major discovery to understand brain development and that bumetanide has shown promising effects in clinical trials.

Bumetanide lowers acute hydrocephalus in a rat model of subarachnoid hemorrhage.

BACKGROUND: Subarachnoid hemorrhage (SAH) can lead to acute hydrocephalus (AH). AH pathophysiology is classically attributed to an obstruction of the arachnoid granulations by blood. Recent findings in rodents suggest that after intraventricular hemorrhage, AH is related to cerebrospinal fluid (CSF) hypersecretion by the choroid plexus (CP), as it can be reduced by intracerebroventricular (ICV) injection of bumetanide. OBJECTIVE: Here, we investigated if and how CSF hypersecretion and/or CSF outflow disorders contribute to post-SAH hydrocephalus. METHODS: Ninety-four Wistar rats were used. SAH was induced by the endovascular perforation technique. The presence of AH was confirmed by magnetic resonance imaging (MRI), and rats with AH were randomly assigned to 4 groups: control group, superior sagittal sinus (SSS) thrombosis to block CSF reabsorption, ICV injection of saline, and ICV injection of bumetanide to decrease CSF secretion. Clinical outcome was evaluated with a neuroscore. A second MRI was performed 24 h later to evaluate the ventricular volume. RESULTS: Fifty percent of rats that survived SAH induction had AH. Their ventricular volume correlated well to the functional outcome after 24 h (r = 0.803). In rats with AH, 24 h later, ventricular volume remained equally increased in the absence of any further procedure. Similarly, ICV injection of saline or SSS thrombosis had no impact on the ventricular volume. However, ICV injection of bumetanide reduced AH by 35.9% (p = 0.002). CONCLUSION: In rodents, post-SAH hydrocephalus is may be due to hypersecretion of CSF by the CP, as it is limited by ICV injection of bumetanide. However, we cannot exclude other mechanisms involved in post-SAH acute hydrocephalus.

Identification of Immune-Related Genes and Small-Molecule Drugs in Interstitial Cystitis/Bladder Pain Syndrome Based on the Integrative Machine Learning Algorithms and Molecular Docking.

Background: Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic, severely distressing clinical syndrome characterized by bladder pain and pressure perceptions. The origin and pathophysiology of IC/BPS are currently unclear, making it difficult to diagnose and formulate successful treatments. Our study is aimed at investigating the role of immune-related genes in the diagnosis, progression, and therapy of IC/BPS. Method: The gene expression datasets GSE11783, GSE11839, GSE28242, and GSE57560 were retrieved from the GEO database for further analysis. Immune-related IC/BPS differentially expressed genes (DEGs) were identified by limma. Three distinct machine learning approaches, least absolute shrinkage and selection operator (LASSO), support vector machine-recursive feature elimination (SVM-RFE), and random forest (RF), were used to find the immune-related IC characteristic genes. Nomogram and receiving operator curves (ROC) were plotted to measure characteristic effectiveness. Using the CMap database and the molecular docking approach, potential small-molecule medicines were found and verified. Consensus cluster analysis was also performed to separate the IC/BPS samples into immunological subtypes. Results: A total of 24 immune-related IC/BPS-DEGs were identified. When compared to the normal control group, the IC/BPS cohort had significantly more immune cell infiltration. Integrative machine learning methods discovered 5 IC/BPS characteristic genes (RASGRP1, PPBP, RBP4, CR2, and PROS2) that may predict IC/BPS diagnosis and immune cell infiltration. Furthermore, two immunological subgroups with substantial variations in immune cell infiltration across IC/BPS samples were identified, which were named cluster1 and cluster2, with the hallmark genes having greater expression in cluster2. Finally, bumetanide was shown to have the potential to be a medication for the treatment of IC/BPS, and it performed well in terms of its molecular binding with RASGRP1. Conclusion: We found and validated 5 immune-related IC/BPS genes (RASGRP1, PPBP, RBP4, CR2, and PROS2) and 2 IC/BPS immune subtypes. In addition, bumetanide was discovered to be a potential drug for treating IC/BPS, which may provide new insight into the diagnosis and immune therapy of IC/BPS patients.

Pharmacological tools to target NKCC1 in brain disorders.

The chloride importer NKCC1 and the chloride exporter KCC2 are key regulators of neuronal chloride concentration. A defective NKCC1/KCC2 expression ratio is associated with several brain disorders. Preclinical/clinical studies have shown that NKCC1 inhibition by the United States FDA-approved diuretic bumetanide is a potential therapeutic strategy in preclinical/clinical studies of multiple neurological conditions. However, bumetanide has poor brain penetration and causes unwanted diuresis by inhibiting NKCC2 in the kidney. To overcome these issues, a growing number of studies have reported more brain-penetrating and/or selective bumetanide prodrugs, analogs, and new molecular entities. Here, we review the evidence for NKCC1 pharmacological inhibition as an effective strategy to manage neurological disorders. We also discuss the advantages and limitations of bumetanide repurposing and the benefits and risks of new NKCC1 inhibitors as therapeutic agents for brain disorders.