Immunosuppressive and cytotoxic effects of furosemide on human peripheral blood mononuclear cells

Furosemide‑induced eradication of myeloblasts via the inhibition of tumor necrosis factor‑α expression in a patient with acute biphenotypic leukemia: A case report

The present study reports the potential of furosemide therapeutic activity in acute myeloid leukemia. A 26-year-old man with acute biphenotypic leukemia was treated with furosemide for suspected pulmonary edema, which was later deemed to be an infiltration of leukemia cells. Notably, the myeloblast population was rapidly eliminated during furosemide therapy. Bone marrow specimens biopsied at different time points were used for immunohistochemical analysis of the expression levels of tumor necrosis factor-α (TNF-α) and its two receptors, TNF-α receptors 1 and 2. The expression of TNF-α and its receptors in the bone marrow was markedly suppressed by furosemide, along with the elimination of the myeloblasts. Thus, it was hypothesized that the growth of myeloblasts in the patient depended on autocrine and/or paracrine TNF-α stimulation, whereas furosemide disrupted this positive feedback loop. Therefore, furosemide is suggested as an effective therapeutic agent for acute myeloid leukemia, at least as an adjunct to standard chemotherapy and gene-targeted therapy.

Adulterated dietary supplements commercialized in Brazil: development of a screening method and a preliminary study of cytotoxicity

The high consumption of dietary supplements was a fundamental driver for the creation of the regulatory framework by the Brazilian governmental authorities. However, the regulatory agencies lack official low-cost methodologies to evaluate the quality of food supplements. A preliminary screening method by HPLC-DAD was proposed and validated for screening and quantification of adulterants in dietary supplements. The limits of detection and quantification were <0.11 and 0.37 µg.g-1, respectively. The method was applied for the investigation of ten unauthorized substances (spironolactone, hydrochlorothiazide, furosemide, clenbuterol, testosterone, testosterone propionate, yohimbine, vardenafil, tadalafil, and sildenafil) with a time of analysis of <5 min. Sixteen percent of the 44 samples analyzed had at least one adulterant at or above therapeutic concentrations. Subsequently, in vitro evaluations were performed of the potential cytotoxicity to evaluate the cell viability, DNA damage, determination of nitric oxide levels, and quantification of reactive oxygen species. Despite the necessity of further studies, the results indicate a relationship between the presence of adulterants in food supplements and a potential cytotoxic effect.

Analysis of Survival Modification by Furosemide Use in a Cohort of Hospitalized COVID-19 Patients with Severe or Critical Disease in Mexico: Due to Its Chemical Structure, Furosemide Is More than Just a Diuretic

In the ongoing fight against Coronavirus Disease 2019 (COVID-19), researchers are exploring potential treatments to improve outcomes, especially in severe cases. This includes investigating the repurposing of existing medications, such as furosemide, which is widely available. This study aimed to evaluate the impact of furosemide on mortality rates among COVID-19 patients with severe or critical illness. We assessed a cohort of 515 hospitalized adults who experienced a high mortality rate of 43.9%. Using a multivariate analysis with adjusted risk ratios (AdRRs), factors like smoking (AdRR 2.48, 95% CI 1.53-4.01, p < 0.001), a high Pneumonia Severity Index (PSI) score (AdRR 7.89, 95% CI 5.82-10.70, p < 0.001), mechanical ventilation (AdRR 23.12, 95% CI 17.28-30.92, p < 0.001), neutrophilia (AdRR 2.12, 95% CI 1.52-2.95, p < 0.001), and an elevated neutrophil-to-lymphocyte ratio (NLR) (AdRR 2.39, 95% CI 1.72-3.32, p < 0.001) were found to increase mortality risk. In contrast, vaccination and furosemide use were associated with reduced mortality risk (AdRR 0.58, p = 0.001 and 0.60, p = 0.008; respectively). Furosemide showed a pronounced survival benefit in patients with less severe disease (PSI < 120) and those not on hemodialysis, with mortality rates significantly lower in furosemide users (3.7% vs. 25.7%). A Kaplan-Meier analysis confirmed longer survival and better oxygenation levels in patients treated with furosemide. Furthermore, a Structure-Activity Relationship analysis revealed that furosemide's sulfonamide groups may interact with cytokine sites such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), potentially explaining its beneficial effects in COVID-19 management. These findings suggest that furosemide could be a beneficial treatment option in certain COVID-19 patient groups, enhancing survival and improving oxygenation.

Alzheimer's Disease and COVID-19 Pathogenic Overlap: Implications for Drug Repurposing

As COVID-19 continues, a safe, cost-effective treatment strategy demands continued inquiry. Chronic neuroinflammatory disorders may appear to be of little relevance in this regard; often indolent and progressive disorders characterized by neuroinflammation (such as Alzheimer's disease (AD)) are fundamentally dissimilar in etiology and symptomology to COVID-19's rapid infectivity and pathology. However, the two disorders share extensive pathognomonic features, including at membrane, cytoplasmic, and extracellular levels, culminating in analogous immunogenic destruction of their respective organ parenchyma. We hypothesize that these mechanistic similarities may extent to therapeutic targets, namely that it is conceivable an agent against AD's immunopathy may have efficacy against COVID-19 and vice versa. It is notable that while extensively investigated, no agent has yet demonstrated significant therapeutic efficacy against AD's cognitive and memory declines. Yet this very failure has driven the development of numerous agents with strong mechanistic potential and clinical characteristics. Having already approved for clinical trials, these agents may be an expedient starting point in the urgent search for an effective COVID-19 therapy. Herein, we review the overlapping Alzheimer's/ COVID-19 targets and theorize several initial platforms.

Nebulized Furosemide for Pulmonary Inflammation in Intubated Patients With COVID-19: A Phase 2 Randomized Controlled Double-Blind Study

OBJECTIVES

Respiratory failure secondary to COVID-19 is associated with morbidity and mortality. Current anti-inflammatory therapies are effective but are given systemically and have significant side effects. Furosemide has anti-inflammatory properties, can be administered by inhalation, and is inexpensive. We investigated the efficacy of nebulized furosemide as an adjunctive therapy for COVID-19 respiratory failure.

DESIGN

A double-blind, randomized, placebo-controlled trial.

SETTING

Multicenter ICU study.

PATIENTS

Adults requiring invasive mechanical ventilation secondary to COVID-19.

INTERVENTION

Patients were randomized within 48 hours of intubation to receive inhaled furosemide or placebo until day 28, death, or liberation from mechanical ventilation.

MEASUREMENTS AND MAIN RESULTS

The study was stopped early due to waning incidence of COVID-19; 39 patients were available for analysis with mean ± sd age of 70.5 (10.8) years, Acute Physiology and Chronic Health Evaluation II 26.1 (7.8) and Fio2 60.0% (21.9). Baseline characteristics were similar between the groups. For the primary outcome of change in Pao2/Fio2 ratio between day 1 and day 6, it was +31.4 (83.5) in the furosemide arm versus +20.1 (92.8) in the control (p = 0.58). For secondary outcomes, furosemide versus control: 60-day mortality was 48% versus 71% (p = 0.20), hospital stay was 25.6 (21.9) versus 27.4 (25.0) days, p = 0.94 and VFD was 6.0 (9.1) versus 3.1 (7.1), p value of equals to 0.28. A post hoc analysis of the hierarchical composite outcome, alive and ventilator-free favored furosemide. There were no adverse events.

CONCLUSIONS

In this trial of inhaled furosemide for COVID-19 respiratory failure, differences in Pao2/Fio2 ratio to day 6 and other clinical outcomes were not significantly different, although the trial was underpowered due to early termination. Given the favorable profile of inhaled furosemide, further study is warranted in disease states where acute pulmonary inflammation contributes to the underlying pathophysiology.

Methazolamide Reduces the AQP5 mRNA Expression and Immune Cell Migration-A New Potential Drug in Sepsis Therapy?

Sepsis is a life-threatening condition caused by the dysregulated host response to infection. Novel therapeutic options are urgently needed and aquaporin inhibitors could suffice as aquaporin 5 (Aqp5) knockdown provided enhanced sepsis survival in a murine sepsis model. Potential AQP5 inhibitors provide sulfonamides and their derivatives. In this study, we tested the hypothesis that sulfonamides reduce AQP5 expression in different conditions. The impact of sulfonamides on AQP5 expression and immune cell migration was examined in cell lines REH and RAW 264.7 by qPCR, Western blot and migration assay. Subsequently, whether furosemide and methazolamide are capable of reducing AQP5 expression after LPS incubation was investigated in whole blood samples of healthy volunteers. Incubation with methazolamide (10-5 M) and furosemide (10-6 M) reduced AQP5 mRNA and protein expression by about 30% in REH cells. Pre-incubation of the cells with methazolamide reduced cell migration towards SDF1-α compared to non-preincubated cells to control level. Pre-incubation with methazolamide in PBMCs led to a reduction in LPS-induced AQP5 expression compared to control levels, while furosemide failed to reduce it. Methazolamide appears to reduce AQP5 expression and migration of immune cells. However, after LPS administration, the reduction in AQP5 expression by methazolamide is no longer possible. Hence, our study indicates that methazolamide is capable of reducing AQP5 expression and has the potential to be used in sepsis prophylaxis.

Il-6 and UGT1A1 variations may related to furosemide resistance in heart failure patients

Furosemide is a diuretic and is used for the treatment of patients with heart failure (HF). It has been found that in some HF patients, the drug does not treat patients efficiently. This condition is named as furosemide resistance. In this study, it is aimed to investigate the relationship between UDP-glucuronosyltransferase 1 (UGT1A1) and interleukine-6 (IL-6) variations with furosemide resistance in HF patients. Sixty HF patients using furosemide (patient group) and 30 healthy individuals (control group) were enrolled in this study. Patients were divided into two subgroups as non-responders (furosemide resistant) group (n = 30) and the responders (non-resistant) group (n = 30) according to the presence of furosemide resistance (n = 30). Variations in the first exon of UGT1A1 and rs1800795 and rs1800796 variations in IL-6 were analyzed by direct sequencing and real-time polymerase chain reaction (RT-PCR), respectively. The effects of newly detected mutations on 3-D protein structure were analyzed by in silico analysis. At the end of the study, 11 variations were detected in UGT1A1, of which nine of them are novel and eight of them cause amino acid change. Also, rs1800795 and rs1800796 variations were detected in all the groups. When patient and control groups were compared with each other, rs1800796 mutation in IL-6 was found statistically high in the patient group (p = 0.027). When the three groups were compared with each other, similarly, rs1800796 mutation in IL-6 was found statistically high in the non-responders group (p = 0.043). When allele distributions were compared between the patient and control groups, the C allele of rs1800795 mutation in IL-6 was found statistically high in the patient group (p = 0.032). When allele distributions were compared between the three groups, 55T-insertion in UGT1A1 was found statistically high in the non-responders group (p = 0.017). According to in silico analysis results, two variations were found deleterious and six variations were detected as probably damaging to protein functions. Our study may contribute to the elucidation of pharmacogenetic features (drug response-gene relationship) and the development of individual-specific treatment strategies in HF patients using furosemide.

Should Renal Inflammation Be Targeted While Treating Hypertension?

Despite extensive research and a plethora of therapeutic options, hypertension continues to be a global burden. Understanding of the pathological roles of known and underexplored cellular and molecular pathways in the development and maintenance of hypertension is critical to advance the field. Immune system overactivation and inflammation in the kidneys are proposed alternative mechanisms of hypertension, and resistant hypertension. Consideration of the pathophysiology of hypertension in chronic inflammatory conditions such as autoimmune diseases, in which patients present with autoimmune-mediated kidney inflammation as well as hypertension, may reveal possible contributors and novel therapeutic targets. In this review, we 1) summarize current therapies used to control blood pressure and their known effects on inflammation; 2) provide evidence on the need to target renal inflammation, specifically, and especially when first-line and combinatory treatment efforts fail; and 3) discuss the efficacy of therapies used to treat autoimmune diseases with a hypertension/renal component. We aim to elucidate the potential of targeting renal inflammation in certain subsets of patients resistant to current therapies.

Captopril Combined with Furosemide or Hydrochlorothiazide Affects Macrophage Functions in Mouse Contact Hypersensitivity Response

Hypertension is a chronic disease associated with chronic inflammation involving activated macrophages. Antihypertensive drugs (for example, angiotensin-converting enzyme inhibitors—ACEIs) used in the treatment of hypertension have immunomodulatory properties. On the other hand, the immunological effect of diuretics and combined drugs (diuretics + ACEI) is unclear. Therefore, we examined the influence of diuretics and combination drugs (ACEI + diuretic) on cellular response (contact hypersensitivity), production of reactive oxygen intermediates (ROIs), and nitric oxide (NO), and the secretion of interleukin-12 (IL-12). CBA mice were administered i.p. captopril (5 mg/kg) with or without hydrochlorothiazide (10 mg/kg) or furosemide (5 mg/kg) for 8 days. On the third day, the mice were administered i.p. mineral oil, and macrophages were collected 5 days later. In the presented results, we show that diuretics administered alone or with captopril increase the generation of ROIs and reduce the formation of NO by macrophages. Moreover, tested drugs inhibit the secretion of IL-12. Diuretics and combined drugs reduce the activity of contact hypersensitivity (both activation and induction phases). Our research shows that the tested drugs modulate the cellular response by influencing the function of macrophages, which is important in assessing the safety of antihypertensive therapy.

Immunomodulatory Potential of Diuretics

In this review, diuretics and their immunomodulatory functions are described. The effects on the immune response of this group of drugs are reported in patients suffering from hypertension and under experimental conditions involving animal models and cell line studies. The pathogenesis of hypertension is strongly connected to chronic inflammation. The vast majority of diuretics modulate the immune response, changing it in favor of the anti-inflammatory response, but depending on the drug, these effects may differ. This topic is significantly important in medical practice regarding the treatment of patients who have coexisting diseases with chronic inflammatory pathogenesis, including hypertension or chronic heart failure. In patients with metabolic syndrome, allergies, or autoimmune disorders, the anti-inflammatory effect is favorable, because of the overstimulation of their immune system. Otherwise, in the geriatric population, it is important to find the proper anti- and pro-inflammatory balance to avoid an enhancement of immune response suppression, which can result in reducing the risk of serious infections that can occur due to the age-diminished function of the immune system. This article is intended to facilitate the selection of an antihypertensive drug that depends on the patient's immune situation.

Anti-Inflammatory Activities of Captopril and Diuretics on Macrophage Activity in Mouse Humoral Immune Response

Hypertension is accompanied by the over-activation of macrophages. Diuretics administered alone or in combination with hypotensive drugs may have immunomodulatory effects. Thus, the influence of tested drugs on mouse macrophage-mediated humoral immunity was investigated. Mice were treated intraperitoneally with captopril (5 mg/kg) with or without hydrochlorothiazide (10 mg/kg) or furosemide (5 mg/kg) by 8 days. Mineral oil-induced peritoneal macrophages were harvested to assess the generation of cytokines in ELISA, and the expression of surface markers was analyzed cytometrically. Macrophages were also pulsed with sheep red blood cells (SRBC) and transferred to naive mice for evaluation of their ability to induce a humoral immune response. Tested drugs increase the expression of surface markers important for the antigen phagocytosis and presentation. SRBC-pulsed macrophages from mice treated with captopril combined with diuretics increased the secretion of antigen-specific antibodies by recipient B cells, while macrophages of mice treated with hydrochlorothiazide or furosemide with captopril increased the number of antigen-specific B cells. Tested drugs alter the macrophage secretory profile in favor of anti-inflammatory cytokines. Our results showed that diuretics with or without captopril modulate the humoral response by affecting the function of macrophages, which has significant translational potential in assessing the safety of antihypertensive therapy.

Immune Function in Critically Ill Septic Children

The inflammatory response in pediatric sepsis is highly dynamic and includes both pro- and anti-inflammatory elements that involve the innate and adaptive immune systems. While the pro-inflammatory response is responsible for the initial clinical signs and symptoms of sepsis, a concurrent compensatory anti-inflammatory response often results in an occult, but highly clinically relevant, form of acquired immunodeficiency. When severe, this is termed "immunoparalysis" and is associated with increased risks for nosocomial infection, prolonged organ dysfunction, and death. This review focuses on the pathophysiology and clinical implications of both over- and under-active immune function in septic children. Host-, disease-, and treatment-specific risk factors for immunoparalysis are reviewed along with immune phenotype-specific approaches for immunomodulation in pediatric sepsis which are currently the subject of clinical trials.

Small molecule therapeutics for COVID-19: repurposing of inhaled furosemide

The novel coronavirus SARS-CoV-2 has become a global health concern. The morbidity and mortality of the potentially lethal infection caused by this virus arise from the initial viral infection and the subsequent host inflammatory response. The latter may lead to excessive release of pro-inflammatory cytokines, IL-6 and IL-8, as well as TNF-α ultimately culminating in hypercytokinemia (“cytokine storm”). To address this immuno-inflammatory pathogenesis, multiple clinical trials have been proposed to evaluate anti-inflammatory biologic therapies targeting specific cytokines. However, despite the obvious clinical utility of such biologics, their specific applicability to COVID-19 has multiple drawbacks, including they target only one of the multiple cytokines involved in COVID-19’s immunopathy. Therefore, we set out to identify a small molecule with broad-spectrum anti-inflammatory mechanism of action targeting multiple cytokines of innate immunity. In this study, a library of small molecules endogenous to the human body was assembled, subjected to in silico molecular docking simulations and a focused in vitro screen to identify anti-pro-inflammatory activity via interleukin inhibition. This has enabled us to identify the loop diuretic furosemide as a candidate molecule. To pre-clinically evaluate furosemide as a putative COVID-19 therapeutic, we studied its anti-inflammatory activity on RAW264.7, THP-1 and SIM-A9 cell lines stimulated by lipopolysaccharide (LPS). Upon treatment with furosemide, LPS-induced production of pro-inflammatory cytokines was reduced, indicating that furosemide suppresses the M1 polarization, including IL-6 and TNF-α release. In addition, we found that furosemide promotes the production of anti-inflammatory cytokine products (IL-1RA, arginase), indicating M2 polarization. Accordingly, we conclude that furosemide is a reasonably potent inhibitor of IL-6 and TNF-α that is also safe, inexpensive and well-studied. Our pre-clinical data suggest that it may be a candidate for repurposing as an inhaled therapy against COVID-19.

Is Inhaled Furosemide a Potential Therapeutic for COVID-19?

The potentially lethal infection caused by the novel Severe Acute Respiratory Disease Coronavirus-2 (SARS-CoV-2) has evolved into a global crisis. Following the initial viral infection is the host inflammatory response that frequently results in excessive secretion of inflammatory cytokines (e.g., IL-6 and TNFα), developing into a self-targeting, toxic "cytokine storm" causing critical pulmonary tissue damage. The need for a therapeutic that is available immediately is growing daily but the de novo development of a vaccine may take years. Therefore, repurposing of approved drugs offers a promising approach to address this urgent need. Inhaled furosemide, a small molecule capable of inhibiting IL-6 and TNFα, may be an agent capable of treating the Coronavirus Disease 2019 cytokine storm in both resource-rich and developing countries. Furosemide is a "repurpose-able" small molecule therapeutics, that is safe, easily synthesized, handled, and stored, and is available in reasonable quantities worldwide.

Pembrolizumab-associated nephrotic syndrome recovered from transient hemodialysis in a patient with lung cancer

A 70-year-old man diagnosed with lung adenocarcinoma was referred to our department for an evaluation of acute onset of nephrotic syndrome with acute kidney injury (AKI) after the 7th course of pembrolizumab treatment. Renal biopsy could not be performed, because he needed anticoagulation therapy for venous thrombosis. Pembrolizumab was discontinued, and prednisolone was started. Hemodialysis was also started, because oliguria was not resolved, and dyspnea due to pulmonary congestion appeared even with the high dose of diuretics. Hemodialysis was successfully withdrawn within 5-week duration because of renal function recovery and increase of urine volume. Complete remission was achieved 4 months after initiating prednisolone. He has never experienced hemodialysis again and remains remission of nephrotic syndrome even the dose of prednisolone was tapered for 8 months. Renal pathology in the current case was uncertain. However, minimal change disease seemed to be a plausible cause of nephrotic syndrome with AKI because of a good response to steroid therapy and acute onset of nephrotic syndrome. In addition, renal pathology in all of the reported cases of pembrolizumab-associated nephrotic syndrome with AKI was minimal change disease. Our case shows for the first time that renal function could be reversible with prednisolone in pembrolizumab-associated nephrotic syndrome with severe AKI even after progression of renal failure which needs dialysis.

Immune Modulation in Pediatric Sepsis

The initial host immune response to sepsis in children is characterized by a proinflammatory surge that can be associated with fever, capillary leak, and organ dysfunction. There is, however, a concurrent anti-inflammatory response that results in hyporesponsiveness of innate and adaptive immune cells. When severe, this response is termed immunoparalysis and is known to be associated with prolonged organ dysfunction, increased risk for nosocomial infection, and death in septic adults and children. Sepsis-induced immune suppression can be defined in the laboratory by reduced whole blood ex vivo - stimulated cytokine production capacities, reduced expression of human leukocyte antigen (HLA)-DR on circulating monocytes, and reduced absolute cell counts. While anti-inflammatory therapies have largely been unsuccessful at improving outcomes from adult and pediatric sepsis, the use of immunostimulatory therapies such as granulocyte macrophage colony-stimulating factor (GM-CSF) in patients with sepsis-induced immunoparalysis shows promise. A greater understanding of the risk factors for immunoparalysis along with the development and execution of immunophenotype-specific clinical trials of strategies to optimize innate and adaptive immune function are needed to further improve outcomes in septic children.

Inhibition of NKCC1 Modulates Alveolar Fluid Clearance and Inflammation in Ischemia-Reperfusion Lung Injury via TRAF6-Mediated Pathways

Background: The expression of Na-K-2Cl cotransporter 1 (NKCC1) in the alveolar epithelium is responsible for fluid homeostasis in acute lung injury (ALI). Increasing evidence suggests that NKCC1 is associated with inflammation in ALI. We hypothesized that inhibiting NKCC1 would attenuate ALI after ischemia-reperfusion (IR) by modulating pathways that are mediated by tumor necrosis-associated factor 6 (TRAF6).

Methods: IR-ALI was induced by producing 30 min of ischemia followed by 90 min of reperfusion in situ in an isolated and perfused rat lung model. The rats were randomly allotted into four groups comprising two control groups and two IR groups with and without bumetanide. Alveolar fluid clearance (AFC) was measured for each group. Mouse alveolar MLE-12 cells were cultured in control and hypoxia-reoxygenation (HR) conditions with or without bumetanide. Flow cytometry and transwell monolayer permeability assay were carried out for each group.

Results: Bumetanide attenuated the activation of p-NKCC1 and lung edema after IR. In the HR model, bumetanide decreased the cellular volume and increased the transwell permeability. In contrast, bumetanide increased the expression of epithelial sodium channel (ENaC) via p38 mitogen-activated protein kinase (p38 MAPK), which attenuated the reduction of AFC after IR. Bumetanide also modulated lung inflammation via nuclear factor-κB (NF-κB). TRAF6, which is upstream of p38 MAPK and NF-κB, was attenuated by bumetanide after IR and HR.

Conclusions: Inhibition of NKCC1 by bumetanide reciprocally modulated epithelial p38 MAPK and NF-κB via TRAF6 in IR-ALI. This interaction attenuated the reduction of AFC via upregulating ENaC expression and reduced lung inflammation.

Modulation of S. epidermidis-induced innate immune responses in neonatal whole blood

BACKGROUND

Coagulase-negative staphylococci (CoNS) such as Staphylococcus epidermidis are highly prevalent pathogens for sepsis in neonates. The interaction between host, environment and pathogenic factors of S. epidermidis are still poorly understood. Our objective was to address the role of several pathogenic factors of S. epidermidis on neonatal cytokine responses and to characterize the influence of three immunomodulatory drugs.

METHODS

We performed an ex-vivo model of S. epidermidis sepsis by assessment of blood cytokine production in neonatal whole blood stimulation assays (ELISA). S. epidermidis strains with different characteristics were added as full pathogen to umbilical cord blood cultures and the influence of indomethacin, ibuprofen and furosemide on neonatal immune response to S. epidermidis was evaluated (Flow cytometry).

RESULTS

Stimulation with S. epidermidis sepsis strains induced higher IL-6 and IL-10 expression than stimulation with colonization strains. Biofilm formation in clinical isolates was associated with increased IL-10 but not IL-6 levels. In contrast, stimulation with mutant strains for biofilm formation and extracellular virulence factors had no major effect on cytokine expression. Notably, addition of ibuprofen or indomethacin to S. epidermidis inoculated whole blood resulted in mildly increased expression of TNF-α but not IL-6, while frusemide decreased the production of pro-inflammatory cytokines, i.e. IL-6 and IL-8.

CONCLUSIONS

The virulence of sepsis strains is coherent with increased cytokine production in our whole-blood in-vitro sepsis model. Biofilm formation and expression of extracellular virulence factors had no major influence on readouts in our setting. It is important to acknowledge that several drugs used in neonatal care have immunomodulatory potential.

Intermittent furosemide administration in patients with or at risk for acute kidney injury: Meta-analysis of randomized trials

Background

Furosemide is the most common loop diuretic used worldwide. The off-label administration of furosemide bolus(es) for the prevention or to reverse acute kidney injury (AKI) is widespread but not supported by available evidence. We conducted a meta-analysis of randomized trials (RCTs) to investigate whether bolus furosemide to prevent or treat AKI is detrimental on patients’ survival.

Methods

Electronic databases were searched through October 2017 for RCTs comparing bolus furosemide administration versus any comparator in patients with or at risk for AKI. The primary endpoint was all-cause longest follow-up mortality. Secondary endpoints included new or worsening AKI, receipt of renal replacement therapy, length of hospital stay, and peak serum creatinine after randomization.

Results

A total of 28 studies randomizing 3,228 patients were included in the analysis. We found no difference in mortality between the two groups (143/892 [16%] in the furosemide group versus 141/881 [16%] in the control group; odds ratio [OR], 0.84; 95% confidence interval [CI], 0.63 to 1.13; p = 0.25). No significant differences in secondary outcomes were found. A significant improvement in survival was found in the subgroup of patients receiving furosemide bolus(es) as a preventive measure (43/613 [7.0%] versus 67/619 [10.8%], OR 0.62; 95% CI, 0.41 to 0.94; p = 0.03)

Conclusions

Intermittent furosemide administration is not associated with an increased mortality in patients with or at risk for AKI, although it may reduce mortality when used as a preventive measure. Future high-quality RCTs are needed to define the role of loop diuretics in AKI prevention and management.

Trial registration

The study protocol was registered on PROSPERO database for systematic reviews (Registration no. CRD42017078607 – http://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42017078607).

Identification of a small molecule that facilitates the differentiation of human iPSCs/ESCs and mouse embryonic pancreatic explants into pancreatic endocrine cells

AIMS/HYPOTHESIS

Pancreatic beta-like cells generated from human induced pluripotent stem cells (hiPSCs) or human embryonic stem cells (hESCs) offer an appealing donor tissue source. However, differentiation protocols that mainly use growth factors are costly. Therefore, in this study, we aimed to establish efficient differentiation protocols to change hiPSCs/hESCs to insulin (INS)⁺ cells using novel small-molecule inducers.

METHODS

We screened small molecules that increased the induction rate of INS⁺ cells from hESC-derived pancreatic and duodenal homeobox 1 (PDX1)⁺ pancreatic progenitor cells. The differentiation protocol to generate INS⁺ cells from hiPSCs/hESCs was optimised using hit compounds, and INS⁺ cells induced with the compounds were characterised for their in vitro and in vivo functions. The inducing activity of the hit compounds was also examined using mouse embryonic pancreatic tissues in an explant culture system. Finally, RNA sequencing analyses were performed on the INS⁺ cells to elucidate the mechanisms of action by which the hit compounds induced pancreatic endocrine differentiation.

RESULTS

One hit compound, sodium cromoglicate (SCG), was identified out of approximately 1250 small molecules screened. When SCG was combined with a previously described protocol, the induction rate of INS⁺ cells increased from a mean ± SD of 5.9 ± 1.5% (n = 3) to 16.5 ± 2.1% (n = 3). SCG induced neurogenin 3-positive cells at a mean ± SD of 32.6 ± 4.6% (n = 3) compared with 14.2 ± 3.6% (n = 3) for control treatment without SCG, resulting in an increased generation of endocrine cells including insulin-producing cells. Similar induction by SCG was confirmed using mouse embryonic pancreatic explants. We also confirmed that the mechanisms of action by which SCG induced pancreatic endocrine differentiation included the inhibition of bone morphogenetic protein 4 signalling.

CONCLUSIONS/INTERPRETATION

SCG improves the generation of pancreatic endocrine cells from multiple hiPSC/hESC lines and mouse embryonic pancreatic explants by facilitating the differentiation of endocrine precursors. This discovery will contribute to elucidating the mechanisms of pancreatic endocrine development and facilitate cost-effective generation of INS⁺ cells from hiPSCs/hESCs.

DATA AVAILABILITY

The RNA sequencing data generated during the current study are available in the Gene Expression Omnibus ( www.ncbi.nlm.nih.gov/geo ) with series accession number GSE89973.

Anti-parasitic effect of the diuretic and Na+-ATPAse inhibitor furosemide in cutaneous leishmaniasis

Leishmania amazonensis promastigotes are known to express furosemide (Lasix®)-sensitive P-type membrane Na+-ATPase. In the present study, furosemide activity was studied in intracellular amastigotes and infected BALB/c mice to investigate its efficacy in cutaneous leishmaniasis (CL). Intracellular parasites, but not macrophages, were found to be sensitive to killing by furosemide (IC50 = 87 µ m vs CC50 ≫ 1000 µ m, respectively). Although furosemide did not induce nitric oxide production or intracellular pH changes in infected macrophages, it led to a significant reactive oxygen species (ROS) burst. Freshly isolated tissue parasites expressed a high degree of Na+-ATPase activity that decreased with culture, indicative of a higher enzyme expression in amastigotes than in promastigotes. Both intraperitoneal and oral treatment of L. amazonensis-infected mice with furosemide dosages equivalent to that prescribed as a diuretic significantly reduced the parasite's growth compared with the situation in untreated mice. Combination with oral furosemide increased the efficacy and safety of intraperitoneal treatment with sodium stibogluconate (SSG). To summarize, furosemide control of intracellular leishmanial growth by means of parasite Na+-ATPase inhibition, and macrophage ROS activation may help explain its sole and SSG-combined therapeutic effect against murine CL.

Lower prevalence of chronic itch in haemodialysis patients on loop diuretics: results from GEHIS (German Epidemiological Hemodialysis Itch Study)

BACKGROUND

Chronic itch (CI) is a very tormenting symptom in haemodialysis (HD) patients. GEHIS (German Epidemiological Hemodialysis Itch Study) is a representative cross-sectional study showing that current chronic itch (CI) affects 25.2% of haemodialysis (HD) patients.

OBJECTIVE

We investigated drug intake and possible associations between CI and medications of HD patients.

METHODS

Eight hundred and sixty HD patients from a randomly selected cluster sample of 25 dialysis units (GEHIS) in Germany were investigated. Statistical analyses were performed using R (version 3.3.0) for Windows. Logistic regression was used to identify influential covariates for prevalence of chronic itch and intensity of itch.

RESULTS

Taking loop diuretics (furosemide, torasemide) was significantly negatively associated with the occurrence of CI in HD patients meaning that those who had received any type of loop diuretics were significantly less likely to suffer from less CI compared to those who had not taken them. There were no associations of CI with other medications. No correlation was detected between the intensity of itch and the intake of loop diuretics or any other medication.

CONCLUSION

Loop diuretics may have an impact on the development of CI in HD patients. As it is most likely that a multifactorial origin may explain CI in HD, future research should also focus on the role of loop diuretics in CI, both on a clinical as well as on a molecular level.

Vascular Surgery Kidney Injury Predictive Score: A Historical Cohort Study

OBJECTIVES

To develop a risk-prediction model for acute kidney injury (AKI) in patients undergoing vascular surgery.

DESIGN

A retrospective cohort study.

SETTING

A tertiary referral center.

PARTICIPANTS

Participants included 845 adult patients who underwent vascular surgery between January 3, 2003, and May 29, 2008.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The median age of patients was 72 years (interquartile range 65-80 years), and 653 patients (77%) were male. AKI developed in 258 (30.5%) patients. Patients with AKI had lower estimated glomerular filtration rates (60±21 v 72±21, p<0.001), were older (73 [68-78] years v 71 [65-80] years, p = 0.01), had a higher prevalence of hypertension (81% v 73%, p = 0.02), and were more likely to undergo emergency surgery (5% v 2%, p = 0.02). Patients with AKI also received more diuretics (p<0.001) and β-blockers (p = 0.003) prior to surgery. The multivariate AKI risk-prediction model with preoperative variables (estimated glomerular filtration rate, previous vascular interventions, use of preoperative diuretics and β-blockers, and emergency surgery) showed an area under the receiver operating characteristic curve of 0.67 (95% confidence interval, 0.628-0.710); a model with additional intraoperative variables (procedure duration, fluid balance, and plasma and platelet transfusion) had an area under the receiver operating characteristic curve of 0.72 (95% confidence interval, 0.685-0.760).

CONCLUSIONS

As AKI is a very common complication after vascular surgery, a risk-prediction model was derived to assess the likelihood of postoperative AKI. If validated in an independent cohort, this model may be used to facilitate targeted interventions in vascular surgery patients at high risk for AKI.

Tailored antihypertensive drug therapy prescribed to older women attenuates circulating levels of interleukin-6 and tumor necrosis factor-α

Objective

To test the hypothesis that antihypertensive drug therapy produces anti-inflammatory effects in clinical practice, this study investigated circulating levels of selected proinflammatory mediators (interleukin-6 [IL-6], tumor necrosis factor-alpha [TNF-α], and interferon-γ [INF-γ]) in response to multivariate drug directions for blood pressure (BP) control.

Methods

Prospective study involving 110 hypertensive, community-dwelling older women with different metabolic disorders. A short-term BP-lowering drug therapy was conducted according to current Brazilian guidelines on hypertension, and basal cytokine levels were measured before and after intervention.

Results

Interventions were found to represent current hypertension-management practices in Brazil and corresponded to a significant reduction in systolic and diastolic BP levels in a whole-group analysis, as well as when users and nonusers of the most common therapeutic classes were considered separately. Considering all patients, mean IL-6 and TNF-α levels showed a significant decrease in circulating concentrations (P<0.01) at the endpoint compared with baseline, whereas the mean INF-γ level was not significantly different from baseline values. In separate analyses, only users of antagonists of the renin–angiotensin system and users of diuretics exhibited the same significant treatment-induced reduction in serum IL-6 and TNF-α observed in the whole group.

Conclusion

Our data demonstrates that a clinically guided antihypertensive treatment is effective in reversing the low-grade proinflammatory state of serum cytokines found in postmenopausal women and support extracardiac benefits from diuretics and renin–angiotensin system antagonists.

Acute kidney injury following acute pancreatitis: A review

BACKROUND. Acute kidney injury (AKI) is a common serious complication of severe acute pancreatitis (SAP) and an important marker of morbidity and mortality in critically ill septic patients. AKI due to severe acute pancreatitis can be the result of hypoxemia, release of pancreatic amylase from the injured pancreas with impairment of renal microcirculation, decrease in renal perfusion pressure due to abdominal compartment syndrome, intraabdominal hypertension or hypovolemia. Endotoxins and reactive oxygen species (ROS) also play an important role in the pathophysiology of SAP and AKI. Knowledge of the pathophysiology and diagnosis of AKI following SAP might improve the therapeutic outcome of critically ill patients.

METHODS AND RESULTS

An overview of the pathophysiology, diagnosis and potential treatment options based on a literature search of clinical human and experimental studies from 1987 to 2013.

CONCLUSIONS

Early recognition of AKI and SAP in order to prevent severe complication like septic shock, intraabdominal hypertension or abdominal compartment syndrome leading to multiple organ dysfunction syndrome is a crucial tool of therapeutic measures in intensive care.

Chronic rhinosinusitis and emerging treatment options

This review describes the epidemiology and various treatments in chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). Evidence for short-term use of systemic corticosteroids has been shown to be favorable in CRSwNP, but still limited in CRSsNP. Topical corticosteroids improve symptom scores in both CRS subgroups. The role of microbes in CRS is still controversial. Culture-directed antibiotics are recommended for CRSsNP with exacerbation. Long-term use of low dosage antibiotics is recommended for CRSsNP for their anti-inflammatory effects. Other emerging treatment options are also discussed.

Which patients with chronic obstructive pulmonary disease benefit from the addition of an inhaled corticosteroid to their bronchodilator? A cluster analysis

OBJECTIVE

To identify subsets of chronic obstructive pulmonary disease (COPD) patients who are more protected from exacerbations with the use of an inhaled corticosteroid/long-acting β2 agonist (ICS/LABA) combination, compared with the use of LABA monotherapy.

DESIGN

Post hoc cluster analysis of patients from two randomised clinical trials of salmeterol/fluticasone propionate (SFC) and salmeterol (SAL) that had primary endpoints of moderate/severe exacerbation rates.

SETTING

Centres in North America.

PARTICIPANTS

1543 COPD patients were studied.

INTERVENTIONS

SFC 50/250 µg or SAL 50 µg, twice daily.

PRIMARY AND SECONDARY OUTCOME MEASURES

The analysis identified clusters of COPD patients more responsive to SFC versus SAL with respect to the annual rate of moderate/severe exacerbations and compared their baseline clinical characteristics.

RESULTS

Overall, SFC significantly reduced the annual rate of moderate/severe exacerbations as compared with SAL alone (rate ratio (RR)=0.701, p<0.001). Three-patient clusters were identified: COPD patients receiving diuretics (RR=0.56, p<0.001); patients not receiving diuretics but with forced expiratory volume in 1 s (FEV1) reversibility ≥12% (RR=0.67, p<0.001) exhibited a substantial reduction in the annual rate of moderate/severe exacerbations relative to SAL. A third cluster, consisting of patients not receiving diuretics and without FEV1 reversibility, demonstrated no difference for SFC versus SAL. Patients receiving diuretics had a significantly higher prevalence of comorbid cardiovascular disease.

CONCLUSIONS

COPD patients receiving diuretics and those not receiving diuretics but with FEV1 reversibility >12% at baseline were significantly more likely to experience a reduction in COPD-associated exacerbations with SFC versus SAL alone.

TRIAL REGISTRATION

NCT00115492, NCT00144911.

Inhibitory effect of furosemide on non-selective voltage-independent cation channels in human erythrocytes

BACKGROUND

Furosemide, a loop diuretic inhibiting the renal tubular Na(+),K(+),2Cl(-) cotransporter, has been shown to decrease cytosolic Ca(2+) concentration ([Ca(2+)](i)) in platelets and erythrocytes. [Ca(2+)](i) in erythrocytes is a function of Ca(2+) permeable cation channels. Activation of those channels e.g. by energy depletion or oxidative stress leads to increase of [Ca(2+)](i), which in turn triggers eryptosis, a suicidal erythrocyte death characterized by cell membrane scrambling. The present study was performed to explore whether furosemide influences the cation channels and thus influences eryptosis.

METHODS

Cation channel activity was determined by whole-cell patch clamp, [Ca(2+)](i) utilizing Fluo3 fluorescence and annexin V binding to estimate cell membrane scrambling with phosphatidylserine exposure.

RESULTS

A 45 min exposure to furosemide (10 and 100 µM) slightly, but significantly decreased cation channel activity and [Ca(2+)](i) in human erythrocytes drawn from healthy individuals. ATP-depletion (> 3 hours, +37°C, 6 mM ionosine and 6 mM iodoacetic acid) enhanced the non-selective cation channel activity, increased [Ca(2+)](i) and triggered cell membrane scrambling, effects significantly blunted by furosemide (10 - 100 µM). Oxidative stress by exposure to tert-butylhydroperoxide (0.1 -1 mM) similarly enhanced the non-selective cation channels activity, increased [Ca(2+)](i) and triggered cell membrane scrambling, effects again significantly blunted by furosemide (10 - 100 µM).

CONCLUSIONS

The present study shows for the first time that the loop diuretic furosemide applied at micromolar concentrations (10 - 100 µM) inhibits non-selective cation channel activity in and eryptosis of human erythrocytes.

GPR35 is a target of the loop diuretic drugs bumetanide and furosemide

We report that the loop diuretic drugs bumetanide and furosemide used in the treatment of hypertension are GPR35 agonists. We utilized calcium flux, inositol phosphate accumulation, and dynamic redistribution assays to examine the pharmacology of these compounds on the human, mouse and rat GPR35. While potent on human GPR35, neither bumetanide nor furosemide were active against mouse or rat GPR35. Furthermore, the Na(+)-Cl(-) cotransporter inhibi- tors chlorothiazide and hydrochlorothiazide were inactive against GPR35 in all three species. We also demonstrate that GPR35 is expressed in human skin where it has been shown that loop diuretics inhibit histamine-induced flare and itch response. These findings suggest that GPR35 may play an important role in skin cell biology and be a potential target for the treatment of a variety of immune disorders.

Quick identification of kuraridin, a noncytotoxic anti-MRSA (methicillin-resistant Staphylococcus aureus) agent from Sophora flavescens using high-speed counter-current chromatography

Bacterial resistance to antibiotics has become a serious problem of public health that concerns almost all currently used antibacterial agents and that manifests in all fields of their application. To find more antibacterial agents from natural resources is all the time considered as an important strategy. Sophora flavescens is a popularly used antibacterial herb in Chinese Medicine, from which prenylated flavones were reported as the antibacterial ingredients but with a major concern of toxicity. In our screening on the antibacterial activities of various chemicals of this herb, 18 fractions were obtained from 8 g of 50% ethanol extract on a preparative high-speed counter-current chromatography (HSCCC, 1000 ml). The system of n-hexane/ethyl acetate/methanol/water (1:1:1:1) was used as the two-phase separation solvent. A chalcone named kuraridin was isolated from the best anti-MRSA fraction, together with sophoraflavanone G, a known active ingredient of S. flavescens. Their structures were elucidated by analysis of the NMR spectra. Both compounds exhibited significant anti-MRSA effects, compared to baicalein that is a well known anti-MRSA natural product. More important, kuraridin showed no toxicity on human peripheral blood mononuclear cells (PBMC) at the concentration up to 64 μg/ml while sophoraflavanone G inhibited over 50% of cellular activity at 4 μg/ml or higher concentration. These data suggested that opening of ring A of the prenylated flavones might decrease the toxicity and remain the anti-MRSA effect, from a viewpoint of structure-activity relationship.

Systemic resistin is increased in type 2 diabetic patients treated with loop diuretics

Increased serum resistin was found in rodent models of obesity and insulin resistance, whereas contradictory results have been obtained in human studies. In humans, resistin is primarily released by monocytes/macrophages, suggesting that soluble levels may be associated with macrophage activation. Here, systemic and monocyte-released resistin levels were found to be similar in type 2 diabetic (T2D) patients, overweight controls and normal-weight controls. When adjusted for body mass index and age, serum resistin modestly correlated with gamma-glutamyltransferase levels, fasting glucose and interleukin-6. Systemic resistin was marginally increased in T2D patients treated with beta-blockers or urate-lowering drugs and was considerably higher in patients treated with loop diuretics. Monocyte-released resistin was even reduced by the loop diuretic furosemide, excluding the possibility that this drug may directly stimulate resistin synthesis. In summary, the current data indicate that changes accompanying renal dysfunction but not obesity or type 2 diabetes are associated with increased serum resistin.

Acute kidney injury: not just acute renal failure anymore?

Until recently, no uniform standard existed for diagnosing and classifying acute renal failure. To clarify diagnosis, the Acute Dialysis Quality Initiative group stated its consensus on the need for a clear definition and classification system of renal dysfunction with measurable criteria. Today the term acute kidney injury has replaced the term acute renal failure, with an understanding that such injury is a common clinical problem in critically ill patients and typically is predictive of an increase in morbidity and mortality. A classification system, known as RIFLE (risk of injury, injury, failure, loss of function, and end-stage renal failure), includes specific goals for preventing acute kidney injury: adequate hydration, maintenance of renal perfusion, limiting exposure to nephrotoxins, drug protective strategies, and the use of renal replacement therapies that reduce renal injury.

Effects of furosemide on allergic asthmatic responses in mice

BACKGROUND

The syndrome of allergic asthma features reversible bronchoconstriction, airway inflammation and hyperresponsiveness as well as airway remodelling, including goblet cell hyperplasia. Managing severe asthma is still a clinical challenge. Numerous studies report that furosemide, an inhibitor of Na(+)-K(+)-Cl(-) cotransporter (NKCC) reduces airway hyperresponsiveness (AHR) in asthmatic patients. However, the mechanism by which furosemide exerts anti-asthmatic action remains unclear.

OBJECTIVE

This study sought to investigate the cellular profile of NKCC1 expression in the lung and examine the effects of furosemide on several outcome measurements in a mouse model of allergic asthma.

METHODS

Mice were sensitized and challenged with ovalbumin (OVA). Before challenge, the OVA-sensitized mice were treated with furosemide (4.0 mg/kg/day, via daily intraperitoneal injection for 5 days). Outcome measurements in naïve, OVA-exposure, furosemide-treated naïve and furosemide-treated OVA-exposed mice included the slope of the relationship between inhaled methacholine (MCh) concentration and respiratory system resistance (Slope·R(RS)), bronchoalveolar lavage (BAL) cell counts and immunohistochemical and immunoblotting assays of lung tissues.

RESULTS

NKCC1 immunoreactivity was observed in airway epithelial cells (AECs) and alveolar type II (ATII) cells of the control mice. OVA exposure enhanced the expression of NKCC1 in AECs and ATII cells, and increased the infiltration of NKCC1-expressing T lymphocytes in the lung. NKCC1 immunoreactivity was not detected in the airway smooth muscle (ASM) cells. Furosemide treatment reduced the Slope·R(RS) in both naïve and OVA-exposed mice by about 50%. Furosemide treatment also increased T lymphocyte infiltration to the lung in OVA-exposed mice by approximately 53%, but had no effect on pulmonary goblet cell hyperplasia.

CONCLUSIONS AND CLINICAL RELEVANCE

Furosemide decreases basal airway responsiveness, thereby reducing the extent of allergen-induced AHR. However, the same treatment also increases T lymphocytes infiltration in the course of allergic asthma. Further studies are necessary to address the usefulness of furosemide in the clinical treatment of asthma.

The pharmacology of acute lung injury in sepsis

Acute lung injury (ALI) secondary to sepsis is one of the leading causes of death in sepsis. As such, many pharmacologic and nonpharmacologic strategies have been employed to attenuate its course. Very few of these strategies have proven beneficial. In this paper, we discuss the epidemiology and pathophysiology of ALI, commonly employed pharmacologic and nonpharmacologic treatments, and innovative therapeutic modalities that will likely be the focus of future trials.

An isomeric mixture of novel cerebrosides isolated from Impatiens pritzellii reduces lipopolysaccharide-induced release of IL-18 from human peripheral blood mononuclear cells

An isomeric mixture of two cerebrosides, soya-cerebrosides I and II, was isolated from an ethno drug, the rhizomes of Impatiens pritzellii Hook. f. var. hupehensis Hook. f., and their structures were identified by spectroscopic (NMR, MS) analysis. In order to determine the immunomodulatory activities of soya-cerebrosides I and II, the effects of the mixture of cerebrosides (MC) on cytotoxicity of human peripheral blood mononuclear cells (PBMC) and the inhibitory activities to lipopolysaccharide (LPS)-induced interleukin (IL)-18 in PBMC were studied. The MC at concentrations of 10 and 1 microM, without toxicity to PBMC in 24 h, showed obvious inhibitory activity on IL-18 secretion. Because of this effect of modulating the cellular immune response, soya-cerebrosides I and II were considered to be the active substances of this ethno drug.

The effect of cardiovascular drugs on pro-inflammatory cytokine secretion and natural killer activity of peripheral blood mononuclear cells of patients with chronic heart failure in vitro

Recent studies have shown that patients with heart failure over-express pro-inflammatory cytokines which enhance natural killer (NK) activity and negatively influence contractility and contribute to the remodeling of myocardium. The question is that how cardiovascular drugs influence on the cytokines of Peripheral Blood Mononuclear Cells (PBMCs) in Chronic Heart Failure (CHF). To study the effect of cardiovascular drugs on PBMCs-cytokines and NK activity of CHF patients. PBMCs of CHF patients/normal controls collected by Ficoll-paque density centrifugation. NK activity against K562 target cell was measured with MTT colorimetric assay. PBMCs were cultivated in RPMI/FCS, stimulated with phytohaemaglutinin (PHA). Tumor necrosis factor (TNF)-alpha interleukin (IL)-6, IL-2 and IL-1beta of culture supernatants after 24 h incubation with/without furosemide, captopril and digoxin were measured with sandwitch ELISA. Patients had higher NK activity than controls (56.9% +/- 1.6 vs 50.9% +/- 1.2, p < 0.05). NK activity of patients who already consumed Captopril/Furosemide didn't show difference with controls. Captopril (3, 1, 0.3 microg mL(-1)) and Furosemide (5, 2.5, 1.25 microg mL(-1)) caused a dose dependent inhibition in TNF-alpha compared with control (329 +/- 23, 427 +/- 15, 519 +/- 19 and 343 +/- 19, 430 +/- 14, respectively vs. 562 +/- 24 pg mL(-1) p < 0.05). Furosemide caused a dose dependent decrease in IL-6 (421 +/- 31, 534 +/- 33 vs. 662 +/- 41 pg mL(-1) p < 0.05). Captopril and Furosemide didn't show any significant effect on IL-1beta/IL-2. Digoxin had no significant effect on PBMCs-cytokines. These data suggest that the immunomodulatory effects of Captopril and Furosemide may contribute to their beneficial and no long-term adverse effects on PBMCs.

Immunoparalysis and adverse outcomes from critical illness

Proper immunologic balance between pro- and anti-inflammatory forces is necessary for recovery from critical illness. Persistence of a marked compensatory anti-inflammatory innate immune response after an insult is termed immunoparalysis. Critically ill patients demonstrating prolonged, severe reductions in monocyte HLA-DR expression or ex vivo tumor necrosis factor alpha production are at high risk for nosocomial infection and death. Reversal of immunoparalysis can be accomplished through the administration of immunostimulatory agents or tapering of exogenous immunosuppression. Evidence suggests that this may be associated with improved clinical outcomes. Immune-monitoring protocols are needed to identify patients who may benefit from immunomodulatory trials.

The efficacy of loop diuretics in acute renal failure: assessment using Bayesian evidence synthesis techniques

OBJECTIVE

To quantify the therapeutic efficacy of loop diuretics in acute renal failure using Bayesian evidence synthesis, because despite widespread use, the role of diuretics is controversial.

DATA SOURCE

Randomized controlled trials or nonrandomized studies, 1966 to January 2007, identified from MEDLINE and EMBASE databases and manual bibliographic search.

STUDY SELECTION

Studies with assessable predefined end points, exclusive of those pertaining to acute renal failure prophylaxis or chronic renal failure.

DATA EXTRACTION

Data extraction was performed jointly by the first two authors; independent study assessment was via standard checklist, unblinded.

DATA SYNTHESIS

The primary outcome was mortality; secondary outcomes were time to renal function normalization and total number of dialyses. Bayesian hierarchical random effects estimates of treatment effects were determined as risk ratio for mortality, incidence rate ratio for dialysis number, and mean difference for continuous measures. Bayesian outcome probabilities were calculated as probability (P) that risk ratio or incidence rate ratio of loop diuretics >1 and probability that mean difference >0. Five randomized controlled trials and eight nonrandomized studies were identified. Loop diuretics were not associated with decreased mortality in either randomized controlled trials or nonrandomized studies: overall risk ratio 1.10; 95% credible interval 0.85, 1.42; P(risk ratio >1) > 83.8%. The oliguric period was decreased by loop diuretics: overall mean difference -7.70 days; 95% credible interval -12.51, -2.08; P (mean difference >0) = 0.7%. Although the dialysis rate credible interval, loop diuretics vs. control, spanned unity (incidence rate ratio 0.71; 95% credible interval 0.47, 1.06), the probability that the incidence rate ratio exceeded unity indicated a substantial benefit: P (incidence rate ratio >1 = 4.1%. Uremic duration was not substantially different, loop diuretics vs. control: overall mean difference -1.54 days; 95% credible interval -5.62, 2.46; P [mean difference >0] = 17.8%).

CONCLUSIONS

Loop diuretics were not associated with improved survival benefit in acute renal failure, despite reduction in oliguric period and high probability of a significant reduction in dialysis numbers. Further studies to clarify this dichotomy appear mandated.

Antihypertensive drugs clonidine, diazoxide, hydralazine and furosemide regulate the production of cytokines by placentas and peripheral blood mononuclear cells in normal pregnancy

BACKGROUND

Antihypertensive drugs such as clonidine, diazoxide, hydralazine and furosemide are used in the hypertensive disorders of pregnancy to control blood pressure, but it is not clear if they modulate the production of placental or circulating cytokines.

OBJECTIVE

To examine the effect of pharmaceutical doses of well known antihypertensive drugs used for blood pressure control on the production of the cytokines interleukin (IL)-6, IL-10 and tumour necrosis factor (TNF)-alpha in placental tissue and peripheral blood mononuclear cells (PBMCs) in normal pregnancy.

DESIGN

Placental biopsies were taken from the decidual surface of placentas after delivery of normal pregnancies (n = 6) and PBMCs were separated from the whole blood of normal term pregnant women (n = 7). Both villous explants and PBMCs were cultured with increasing concentrations of antihypertensive drugs. The dose effect of drugs on the production of placental and circulating cytokines (IL-6, IL-10 and TNF-alpha) were examined by enzyme-linked immunosorbent assay.

RESULTS

Placental production of IL-10 was not affected by clonidine, but decreased significantly after incubation of the tissue with diazoxide, hydralazine or furosemide. Production of IL-10 by PBMCs increased significantly: by from 3.4 +/- 2.7% [16.3 pg/ml (range 6.1-21.5 pg/ml)] to 24.5 +/- 3.3% [30.4 pg/ml (range 16.9-34.8 pg/ml)] with increasing concentrations of clonidine (0.08-1.3 microg/ml), and by 8.8 +/- 3.5% [4.1 pg/ml (range 3.0-17.8 pg/ml)] and 17.2 +/- 1.9% [22.6 pg/ml (range 13.2-23.2 pg/ml)] with lower doses of hydralazine (6.3 and 12.5 microg/ml) (all P values < 0.05). There was a stepwise reduction in production of TNF-alpha and IL-6 with increasing doses of diazoxide, hydralazine and furosemide by placentas and PBMCs from these women with normal pregnancies.

CONCLUSION

Our data suggest that the antihypertensive drugs clonidine and hydralazine can stimulate production of the circulating anti-inflammatory cytokine IL-10, whereas furosemide and diazoxide inhibit the production of this cytokine and the proinflammatory cytokines TNF-alpha and IL-6 by placentas and PBMCs.

Topical furosemide versus oral steroid in preoperative management of nasal polyposis

The efficacy of topical nasal furosemide treatment has been shown in the protection of nasal polyp recurrence. The aim of the study was to compare the effect of oral steroid, as standard preoperative treatment, and inhaled furosemide, as alternative treatment, for 7 days preoperatively in terms of subjective improvement of nasal symptoms, polyp size reduction, inflammation in the polyp tissue, and intraoperative blood loss. A group of 40 patients with nasal polyposis entered the study and they were randomly allocated to 7-day preoperative treatment with either oral methylprednisolon (1 mg/kg/day) or topical furosemide by inhalation (6.6 mmol/l solution). Subjective scores of rhinosinusitis symptoms, polyp scores at endoscopy, and biopsy of the most superficial polyp were taken at inclusion. All procedures were repeated on day 7. Intraoperative blood loss was estimated (scores 0-10) by the surgeon at the operation. Eosinophils, mastocytes, and oedema were quantified by histomorphometry. Subjective symptoms and endoscopy scores did not differ significantly between the groups after the treatment although improvement of olfaction was insignificantly better in the steroid group. Steroid treatment significantly reduced eosinophil count, with no effect on mastocytes and oedema. Furosemide treatment did not affect inflammatory cells count significantly, but it has significantly reduced oedema in previously unoperated patients. No difference in intraoperative bleeding was observed between the groups.

Inhibitory effect of furosemide on activation of human peripheral blood polymorphonuclear leukocytes stimulated with n-formyl-methionyl-leucyl-phenylalanine

The clinical efficacy of inhalatory furosemide (Fu) has been extensively studied in bronchial asthma patients but there are only a few studies addressing its action on cells participating in the underlying inflammatory process. Therefore, we investigated the effect of Fu on human peripheral blood polymorphonuclear leukocytes (PMNL) at concentrations that can be achieved in the bronchial lining fluid by inhalation, i.e. 10(-5), 10(-4) and 10(-3) M. The influence of Fu on the following PMNL parameters was investigated: intracellular calcium changes ([Ca2+]i) as a part of signal transduction and luminol dependent chemiluminescence (LCL) as an indirect measure of NADPH-oxidase activation upon n-formyl-methionyl-leucyl-phenylalanine (fMLP) stimulation; chemotaxis to fMLP, phagocytosis and intracellular killing of Staphylococcus aureus. Incubation with Fu resulted in a concentration dependent reduction of Ca2+ influx and Fu (10(-3) M) decreased the main Ca2+ parameters to one half of the control values and to the level obtained in calcium-free buffer. In contrast, Fu had no effect if preincubated with the cells and then removed by washing. The LCL signal was reduced by Fu (10(-3) M) from 2000 +/- 870 to 550 +/- 440 arbitrary units [aU] (p<0.05). In contrast to the [Ca2+]i measurements, a slightly diminished LCL was also observed following preincubation with Fu and washing. No effect of Fu was found on phagocytosis and intracellular killing of St. aureus. Fu diminished chemotaxis to fMLP but at 10(-3) M it also displayed weak chemoattractant properties. The differential action of Fu on human PMNL may add to the understanding of its topical and restricted efficacy in bronchial asthma.

Pharmacology of airway inflammation in asthma and COPD

The current asthma therapies are not cures and symptoms return soon after treatment is stopped even after long term treatment. Although inhaled glucocorticoids are highly effective in controlling airway inflammation in asthma, they are ineffective in the small group of patients with glucocorticoid-dependent and -resistant asthma. With very few exceptions, COPD is caused by tobacco smoking, and smoking cessation is the only truly effective treatment of COPD available. Current pharmacological treatment of COPD is unsatisfactory, as it does not significantly influence the severity of the disease or its natural course. Glucocorticoids are scarcely effective in COPD patients without concomitant asthma. Bronchodilators improves symptoms and quality of life, in COPD patients, but, with the exception of tiotropium, they do not significantly influence the natural course of the disease. Theophylline is the only drug which has been demonstrated to have a significant effect on airway inflammation in patients with COPD. Here we review the pharmacology of currently used antiinflammatory therapies for asthma and COPD and their proposed mechanisms of action. Recent understanding of disease mechanisms in severe steroid-dependent and -resistant asthma and in COPD, has lead to the development of novel compounds, which are in various stages of clinical development. We review the current status of some of these new potential drugs.

Furosemide: progress in understanding its diuretic, anti-inflammatory, and bronchodilating mechanism of action, and use in the treatment of respiratory tract diseases

Accumulated experimental and clinical data suggest that adrenocorticosteroids and/or endogenous ouabain-like substances may play an important role in the mechanism of furosemide diuretic action. It was reported that the drug is highly bound in the adrenals, lungs, kidney, spleen, and liver. In patients with liver cirrhosis, furosemide exerted a markedly decreased natriuretic effect compared with normal subjects, and the plasma levels of circulating endothelin and atrial natriuretic factor (ANF) were significantly elevated. In neonates, after administration of furosemide, the urinary excretion of endothelin-1 and aldosterone increased markedly, and it is known that endothelin may release ANF and aldosterone in a dose-dependent manner. Furosemide was used to stimulate zona glomerulosa, whereas ANF decreased the production of steroids in zona glomerulosa and fasciculata cell culture owing to stimulation by various factors. Because the concomitant use of ANF and furosemide appeared to be diuretically effective in newborns after cardiac surgery, one may suggest that furosemide competes with ANF for its effects on the adrenals. Furosemide administered by inhalation exerted a protective effect on allergic and perennial nonallergic rhinitis and was effective in preventing the postsurgical recurrence of nasal polyposis. The drug can also be used as an antiasthmatic agent. In preterm ventilator-dependent infants with chronic lung disease, aerosolized furosemide improved pulmonary function with no marked effect on diuresis. In adults and children with asthma, furosemide exerted a protective effect against bronchoconstriction induced by several indirect stimuli similar to that of disodium cromoglycate or nedocromil. Aerosolized furosemide had a preventive effect also on bronchoconstriction induced by inhaled lysine acetylsalicylate in patients with aspirin-sensitive asthma. In high-dose beclomethasone-dependent asthma, inhaled lysine acetylsalicylate and furosemide exerted a mutually potentiating antiasthmatic activity, allowing considerable sparing of the inhaled steroid. It is proposed that this effect may be explained by the corticosteroid-sparing action of lysine released from the lysine acetylsalicylate molecule because similar beneficial effects were also obtained after the concomitant use of epsilon-aminocaproic acid (whose chemical structure is almost the same as that of lysine) and prednisone. Furosemide exhibited an anti-inflammatory effect through inhibition of production and release of cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor-alpha from peripheral mononuclear cells, which may have a beneficial effect on local inflamed tissue imbalance in the ratio of different cytokines, thus improving the sensitivity of target cells to endogenous glucocorticosteroids.

Clinical pharmacology of furosemide in children: a supplement

Furosemide is one of the most effective and least toxic diuretics used in pediatric practice. Experimental and clinical data suggest that adrenocorticosteroids and/or endogenous ouabain-like substances may play an important role in its diuretic effect. Also, the drug appears to have anti-inflammatory properties. In children with different diseases who received orally or intravenously 1 to 2 mg/kg doses of furosemide, a statistically significant positive linear relationship was found between the drug urinary excretion rate and the urine flow rate, but log dose-response curves to the drug were found to vary depending on the disease and the route of the drug administration. No sigmoid-shaped log dose-response curve (ie, one approaching a zero response at very low furosemide urinary excretion rates and a maximum response at very high excretion rates) was attained, which may suggest that the capacity of the kidney tubules to respond diuretically to the aforementioned doses of furosemide was not exceeded in these patients. However, in infants with different diseases and reasonably normal renal function who required administration of this diuretic, a very steep log dose-response curve to a 1 mg/kg intravenous dose of furosemide was found, which may suggest that higher doses may not result in a significant increase in diuretic response. The lowest mean furosemide urinary excretion rate and its concentration in urine associated with a significant diuresis were found to be 0.58 +/- 0.33 microg/kg/min and 24.2 +/- 10.5 microg/ml, respectively. Also, a significant correlation was found between the amount (in milligrams) of furosemide excreted in the urine during the first 6 hours after administration and the urine volume collected during that time. Patients with cystic fibrosis appeared to have a markedly more pronounced diuretic response to the average oral dose of 0.835 +/- 0.18 mg/kg than that reported in control children given 2 mg/kg. In children with acute renal failure caused by acute gastroenterocolitis or glomerulonephritis, a broad relationship was observed between a single intravenous dose and diuretic response after administration of furosemide (1.2 to 30.8 mg/kg). It was suggested that the total daily dose of the drug should not exceed 100 mg in these patients. Furosemide was found to be effective in management of bronchoconstriction accompanying chronic lung disease and narrowing of the upper respiratory airways; in hydrocephalus in infancy to avoid cerebrospinal fluid shunts; in some diagnostic procedures, such as an assessment of fetal and neonatal hydronephrosis; and in evaluation of different types of renal tubular acidosis. Among side effects accompanying clinical use of this drug were cholelithiasis in premature infants receiving total parenteral nutrition concomitantly with the diuretic; secondary hyperparathyroidism and bone disease in infants obtaining long-term furosemide treatment; and drug-induced fever.