The lonidamine derivative H2-gamendazole reduces cyst formation in polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is a debilitating renal neoplastic disorder with limited treatment options. It is characterized by the formation of large fluid-filled cysts that develop from kidney tubules through abnormal cell proliferation and cyst-filling fluid secretion driven by cAMP-dependent Cl- secretion. We tested the effectiveness of the indazole carboxylic acid H2-gamendazole (H2-GMZ), a derivative of lonidamine, to inhibit these processes using in vitro and in vivo models of ADPKD. H2-GMZ was effective in rapidly blocking forskolin-induced, Cl--mediated short-circuit currents in human ADPKD cells, and it significantly inhibited both cAMP- and epidermal growth factor-induced proliferation of ADPKD cells. Western blot analysis of H2-GMZ-treated ADPKD cells showed decreased phosphorylated ERK and decreased hyperphosphorylated retinoblastoma levels. H2-GMZ treatment also decreased ErbB2, Akt, and cyclin-dependent kinase 4, consistent with inhibition of heat shock protein 90, and it decreased levels of the cystic fibrosis transmembrane conductance regulator Cl- channel protein. H2-GMZ-treated ADPKD cultures contained a higher proportion of smaller cells with fewer and smaller lamellipodia and decreased cytoplasmic actin staining, and they were unable to accomplish wound closure even at low H2-GMZ concentrations, consistent with an alteration in the actin cytoskeleton and decreased cell motility. Experiments using mouse metanephric organ cultures showed that H2-GMZ inhibited cAMP-stimulated cyst growth and enlargement. In vivo, H2-GMZ was effective in slowing postnatal cyst formation and kidney enlargement in the Pkd1flox/flox: Pkhd1-Cre mouse model. Thus, H2-GMZ treatment decreases Cl- secretion, cell proliferation, cell motility, and cyst growth. These properties, along with its reported low toxicity, suggest that H2-GMZ might be an attractive candidate for treatment of ADPKD.NEW & NOTEWORTHY Autosomal dominant polycystic kidney disease (ADPKD) is a renal neoplastic disorder characterized by the formation of large fluid-filled cysts that develop from kidney tubules through abnormal cell proliferation and cyst-filling fluid secretion driven by cAMP-dependent Cl- secretion. This study shows that the lonidamine derivative H2-GMZ inhibits Cl- secretion, cell proliferation, and cyst growth, suggesting that it might have therapeutic value for the treatment of ADPKD.

Sub-acute hyponatraemia more than chronic hyponatraemia is associated with serious falls and hip fractures.

BACKGROUND: Falls and hip fractures among older people are associated with high morbidity and mortality. Hyponatraemia may be a risk for falls/hip fractures, but the effect of hyponatraemia duration is not well understood. AIMS: To evaluate individuals with periods of sub-acute and chronic hyponatraemia on subsequent risk for serious falls and/or hip fractures. METHODS: Retrospective cohort study in the period 1 January 1998 to 14 June 2016 within an integrated health system of individuals aged ≥55 years with ≥2 outpatient serum sodium measurements. Hyponatraemia was defined as sodium <135 mEq/L with sub-acute (<30 days) and chronic (≥30 days) analysed as a time-dependent exposure. Multivariable Cox proportional-hazards modelling was used to estimate hazard ratios (HR) for serious falls/hip fractures based on sodium category. RESULTS: Among 1 062 647 individuals totalling 9 762 305 sodium measurements, 96 096 serious falls/hip fracture events occurred. Incidence (per-1000-person-years) of serious falls/hip fractures were 11.5, 27.9 and 19.8 for normonatraemia, sub-acute and chronic hyponatraemia. Any hyponatraemia duration compared to normonatraemia had a serious falls/hip fractures HR (95%CI) of 1.18 (1.15, 1.22), with sub-acute and chronic hyponatraemia having HR of 1.38 (1.33, 1.42) and 0.91 (0.87, 0.95), respectively. Examined separately, the serious falls HR was 1.37 (1.32, 1.42) and 0.92 (0.88, 0.96) in sub-acute and chronic hyponatraemia, respectively. Hip fracture HR were 1.52 (1.42, 1.62) and 1.00 (0.92, 1.08) for sub-acute and chronic hyponatraemia, respectively, compared to normonatraemia. CONCLUSIONS: Our findings suggest that early/sub-acute hyponatraemia appears more vulnerable and associated with serious falls/hip fractures. Whether hyponatraemia is a marker of frailty or a modifiable risk factor for falls remains to be determined.

Data driven approach to characterize rapid decline in autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic kidney disease with high phenotypic variability. Furthering insights into patients' ADPKD progression could lead to earlier detection, management, and alter the course to end stage kidney disease (ESKD). We sought to identify patients with rapid decline (RD) in kidney function and to determine clinical factors associated with RD using a data-driven approach. A retrospective cohort study was performed among patients with incident ADPKD (1/1/2002-12/31/2018). Latent class mixed models were used to identify RD patients using differences in eGFR trajectories over time. Predictors of RD were selected based on agreements among feature selection methods, including logistic, regularized, and random forest modeling. The final model was built on the selected predictors and clinically relevant covariates. Among 1,744 patients with incident ADPKD, 125 (7%) were identified as RD. Feature selection included 42 clinical measurements for adaptation with multiple imputations; mean (SD) eGFR was 85.2 (47.3) and 72.9 (34.4) in the RD and non-RD groups, respectively. Multiple imputed datasets identified variables as important features to distinguish RD and non-RD groups with the final prediction model determined as a balance between area under the curve (AUC) and clinical relevance which included 6 predictors: age, sex, hypertension, cerebrovascular disease, hemoglobin, and proteinuria. Results showed 72%-sensitivity, 70%-specificity, 70%-accuracy, and 0.77-AUC in identifying RD. 5-year ESKD rates were 38% and 7% among RD and non-RD groups, respectively. Using real-world routine clinical data among patients with incident ADPKD, we observed that six variables highly predicted RD in kidney function.

Health Disparities in Kidney Failure Among Patients With Autosomal Dominant Polycystic Kidney Disease: A Cross-Sectional Study.

Rationale & Objective: Understanding potential differences in patterns of kidney failure among patients with autosomal dominant polycystic kidney disease (ADPKD) may provide insights into improving disease management. We sought to characterize patients with ADPKD and kidney failure across different race/ethnicities. Study Design: Cross-sectional study. Setting & Participants: Kaiser Permanente Southern California members diagnosed with ADPKD between January1, 2002, and December 31, 2018. Exposure: ADPKD. Outcome: Kidney failure, dialysis, or receipt of kidney transplant. Analytical Approach: Differences in characteristics by race/ethnicity were assessed using analysis of variance F test and χ2 test. To compare the range and distribution of the average age at onset of kidney failure by race/ethnicity and sex, we used box plots and confidence intervals. Multivariable logistic regression was used to estimate OR for kidney transplant. Results: Among 3,677 ADPKD patients, 1,027 (27.3%) had kidney failure. The kidney failure cohort was comprised of Black (n=138; 30.7%), White (n=496; 30.6%), Hispanic (n=306; 24.7%), and Asian (n=87; 23.6%) patients. Hispanic patients had the youngest mean age of kidney failure onset (50 years) compared to Black (56 years) and White (57 years) patients. Black (44.2%; OR, 0.72) and Hispanic (49.7%; OR, 0.65) patients had lower rates of kidney transplantation compared to White (53.8%) patients. Preemptive kidney transplantations occurred in 15.0% of patients. Limitations: Retrospective study design and possible misclassification of ADPKD cases. Kidney function calculations were based on equations incorporating race, potentially overestimating kidney function in African Americans. The study was conducted within a single, integrated health care system in 1 geographic region and may not be generalizable to all ADPKD patients. Conclusions: Among a large diverse ADPKD population, we observed racial/ethnic differences in rates of kidney failure, age of kidney failure onset, and rates of kidney transplantation. Our real-world ADPKD cohort provides insight into racial/ethnic variation in clinical features of disease and potential disparities in care, which may affect ADPKD outcomes.

Costs associated with unplanned readmissions among patients with heart failure with and without hyponatremia.

PURPOSE: Costs associated with unplanned readmissions among patients with heart failure with and without hyponatremia were studied. METHODS: This study estimated the costs of patients hospitalized for heart failure (HF) discharged with or without corrected sodium. A model was developed to monetize the 30-day readmission risk based on hyponatremia correction. Costs of discharging patient with corrected versus uncorrected hyponatremia were estimated using readmission rates from a previously published study and hospitalization costs from the Healthcare Costs and Utilization Cost Project and the Premier Healthcare Database. RESULTS: Discharging patients with HF and hyponatremia increased costs from $488-$569 per discharge compared to patients with corrected hyponatremia. This range reflected differences in readmission rates and sources of hospitalization costs. Sensitivity analyses showed hospitalization costs and readmission rates had the largest impact on model results. CONCLUSION: A retrospective study supports the value of upfront monitoring and correction of low serum sodium levels before discharge among patients with HF and hyponatremia by presenting an economic argument in addition to the clinical rational for reducing risk of readmission.

Economic impact of tolvaptan treatment vs. fluid restriction based on real-world data among hospitalized patients with heart failure and hyponatremia.

OBJECTIVES: To estimate the cost difference associated with tolvaptan treatment vs. fluid restriction (FR) among hospitalized patients with heart failure (HF) and hyponatremia (HN) based on a real-world registry of HN patients. METHODS: An Excel-based economic model was developed to evaluate the cost impact of tolvaptan treatment vs. FR. Model input for hospital length of stay (LOS) was based on published data from the Hyponatremia Registry (HNR). Based on HNR data, tolvaptan-treated patients had a 2-day (median) shorter LOS compared to FR. Real-world effectiveness of tolvaptan treatment from the HNR was applied to a national sample of inpatients visits from the Premier Hospital database to estimate the potential LOS-related cost difference between tolvaptan treatment and FR. A one-way sensitivity and multivariable Monte Carlo sensitivity analysis were conducted. RESULTS: Economic modeling results of the base-case analysis indicated that among hospitalized patients with HF, the hospital cost per admission, not including HN drug cost, was $3453 lower among patients treated with tolvaptan vs. FR, due to the shorter LOS associated with tolvaptan treatment. At wholesale acquisition cost of $362 per day and an average treatment duration of 3.2 days, the pharmacy cost of tolvaptan treatment per admission was estimated at $1157. Thus, after factoring the decrease in hospital medical costs and increase in pharmacy costs associated with tolvaptan treatment, results indicated a cost-offset opportunity of -$2296 per admission for patients treated with tolvaptan versus FR. Results of the sensitivity analyses were consistent with the base-case analysis. LIMITATIONS: The model derives inputs from real-world observational data. No causal relationship can be inferred from this analysis. CONCLUSIONS: Based on this economic analysis, tolvaptan treatment vs. FR among hospitalized patients with HF and HN may be associated with lower hospital-related costs, which offset the increase in pharmacy costs associated with tolvaptan treatment.

Utilization and budget impact of tolvaptan in the inpatient setting among patients with heart failure and hyponatremia.

OBJECTIVE: Assess characteristics of patients with heart failure (HF) and hyponatremia (HN) using tolvaptan, a selective vasopressin V2-receptor antagonist, for sodium correction, and estimate the budget impact of tolvaptan use in a hospital. METHODS: The Premier hospital database was analyzed to assess the utilization of tolvaptan, characteristics of users and non-users, and hospitalization costs among patients with HF and HN. Using these findings, a model was developed to estimate tolvaptan costs in proportion to total medical costs of managing patients with HF and HN, and the budget impact of tolvaptan use. Results were regenerated using data from the Healthcare Cost and Utilization Project (HCUP) database, and robustness was assessed in sensitivity analyses. RESULTS: Tolvaptan was used in 4.96% of inpatient visits among patients with HF and HN, more commonly among sicker patients as reflected in high utilization during intensive care stays (30.46%). Additionally, utilization increased by length of stay, which can serve as a proxy for disease severity. The model estimated that tolvaptan costs accounted for 0.3% of total hospitalization-related costs for patients with HF and HN, and the budget impact was $52.42 per visit. CONCLUSIONS: Results demonstrate that tolvaptan is used infrequently among patients with HF and HN, and is utilized among sicker patients. Tolvaptan accounted for 0.3% of total spending on management of inpatient visits with HF and HN, and had a marginal impact on hospital budget when compared with fluid restriction for HN correction. Availability of tolvaptan can provide an additional therapeutic option for sodium correction.

Extracellular signal-regulated kinase 5 promotes acute cellular and systemic inflammation.

Inflammatory critical illness is a syndrome that is characterized by acute inflammation and organ injury, and it is triggered by infections and noninfectious tissue injury, both of which activate innate immune receptors and pathways. Although reports suggest an anti-inflammatory role for the mitogen-activated protein kinase (MAPK) extracellular signal-regulated kinase 5 (ERK5), we previously found that ERK5 mediates proinflammatory responses in primary human cells in response to stimulation of Toll-like receptor 2 (TLR2). We inhibited the kinase activities and reduced the abundances of ERK5 and MEK5, a MAPK kinase directly upstream of ERK5, in primary human vascular endothelial cells and monocytes, and found that ERK5 promoted inflammation induced by a broad range of microbial TLR agonists and by the proinflammatory cytokines interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α). Furthermore, we found that inhibitors of MEK5 or ERK5 reduced the plasma concentrations of proinflammatory cytokines in mice challenged with TLR ligands or heat-killed Staphylococcus aureus, as well as in mice that underwent sterile lung ischemia-reperfusion injury. Finally, we found that inhibition of ERK5 protected endotoxemic mice from death. Together, our studies support a proinflammatory role for ERK5 in primary human endothelial cells and monocytes, and suggest that ERK5 is a potential therapeutic target in diverse disorders that cause inflammatory critical illness.

Lung Ischemia-Reperfusion is a Sterile Inflammatory Process Influenced by Commensal Microbiota in Mice.

Lung ischemia-reperfusion (IR) complicates numerous clinical processes, such as cardiac arrest, transplantation, and major trauma. These conditions generate sterile inflammation, which can cause or worsen acute lung injury. We previously reported that lung and systemic inflammation in a mouse model of ventilated lung IR depends on Toll-like receptor 4 (TLR-4) signaling and the presence of alveolar macrophages. Here, we tested the hypothesis that the intestinal microbiome has a role in influencing the inflammatory response to lung IR. Lung IR was created in intubated mechanically ventilated mice via reversible left pulmonary artery occlusion followed by reperfusion. Inflammatory markers and histology were tracked during varying periods of reperfusion (from 1 to 24 h). Separate groups of mice were given intestinally localized antibiotics for 8 to 10 weeks and then were subjected to left lung IR and analysis of lungs and plasma for markers of inflammation. Alveolar macrophages from antibiotic-treated or control mice were tested ex vivo for inflammatory responses to bacterial TLR agonists, namely, lipopolysaccharide and Pam3Cys. We found that inflammation generated by left lung IR was rapid in onset and dissipated within 12 to 24 h. Treatment of mice with intestinally localized antibiotics was associated with a marked attenuation of circulating and lung inflammatory markers as well as reduced histologic evidence of infiltrating cells and edema in the lung after IR. Alveolar macrophages from antibiotic-treated mice produced less cytokines ex vivo when stimulated with TLR agonists as compared with those from control mice. Our data indicate that the inflammatory response induced by nonhypoxic lung IR is transient and is strongly influenced by intestinal microbiota. Furthermore, these data suggest that the intestinal microbiome could potentially be manipulated to attenuate the post-IR pulmonary inflammatory response.

Differential regulation of cytokines and transcription factors in liver by curcumin following hemorrhage/resuscitation.

Inflammatory cytokines interleukin 1 (IL-1), IL-2, IL-6, and tumor necrosis factor-alpha (TNF-alpha) have been recognized as important mediators of pathophysiological and immunological events associated with shock. These inflammatory events after hemorrhage and resuscitation are characterized by the activation of transcription regulators such as nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1). Curcumin, an anti-inflammatory remedy used in Indian medicine, is known to suppress NF-kappaB and AP-1 activation and also to reduce ischemia-reperfusion injuries in animal models. Therefore, the aim of this study was to determine whether administration of curcumin before hemorrhagic shock has any salutary effects on cytokines and the redox-sensitive transcription factors NF-kappaB and AP-1. mRNA levels of IL-1alpha, IL-1beta, IL-2, IL-6, IL-10, and TNF-alpha were determined by reverse transcriptase-polymerase chain reaction in rat livers collected at 2 and 24 h after hemorrhage/resuscitation. The effect of curcumin on the activation of NF-kappaB and AP-1 was determined by electrophoretic mobility shift assays. Significant increases in the levels of liver cytokines IL-1alpha, IL-1beta, IL-2, IL-6, and IL-10 were observed in the 2-h posthemorrhage/resuscitation group compared with sham animals. In contrast, oral administration of curcumin for 7 days followed by hemorrhage/resuscitation regimen resulted in significant restoration of these cytokines to depleted levels, and, in fact, IL-1beta levels were lower than sham levels. Also, the 24-h postresuscitation group showed similar patterns with some exceptions. NF-kappaB and AP-1 were differentially activated at 2 and 24 h posthemorrhage and were inhibited by curcumin pretreatment. Serum aspartate transaminase estimates indicate decreased liver injury in curcumin-pretreated hemorrhage animals. These results suggest that protection against hemorrhage/resuscitation injury by curcumin pretreatment may result from the inactivation of transcription factors involved and regulation of cytokines to beneficial levels.

Picroliv modulates antioxidant status and down-regulates AP1 transcription factor after hemorrhage and resuscitation.

Resuscitation from hemorrhagic shock initiates profound changes in the liver that are likely to contribute to end organ damage and resultant dysfunction after shock. Extensive research in this area has indicated the potential of free radical scavenging strategy for better management of the pathophysiology following hemorrhage-resuscitation (H/R) injury. We studied the effect of a novel pharmacological agent, picroliv, on hepatocellular injury and redox status, as well as its possible mechanism of action in a H/R model in adult rats. Anesthetized rats were subjected to hemorrhagic shock by bleeding 30 mL/kg body weight. After 60 min of shock, rats were resuscitated with twice the shed blood volume of lactated Ringer's solution and were sacrificed 2 h after resuscitation. We observed that picroliv (12 mg/kg) pretreatment, given orally for 7 days, resulted in a significant decrease in serum aspartate transaminase and gamma-glutamyl transpeptidase levels. Picroliv also inhibited the lipid peroxidation and nitric oxide release that occurred after H/R and altered the activity of glutathione reductase in a favorable manner, thereby suggesting better antioxidant status. Picroliv significantly down-regulated the stress-sensitive transcription factor AP1 and decreased the level of c-fos mRNA as well as c-jun and c-fos proteins in liver tissue, indicating that its actions could be mediated through AP1 and associated signal transduction pathways. These findings suggest that picroliv has the potential to be developed as a protective agent against H/R injury.

Hemorrhagic shock induces differential gene expression and apoptosis in mouse liver.

Comprehensive knowledge of the gene expression changes induced by hemorrhage in vital organs will greatly improve prognosis and therapy. Therefore, we used a mouse model of non-resuscitated hemorrhagic shock to study the pattern of stress-induced genes in liver at 1, 4, and 24 h following surgery. Hepatic injury was confirmed by assessment of liver injury markers and apoptotic cell death. We found that a variety of stress-regulated genes were differentially expressed, including seven genes that have not been reported previously as being regulated by hemorrhagic shock: ATF-2, alphaB-crystallin, GADD45, GADD45beta, Mdm2, p21Waf1, and TRPM-2. The changes in mRNA levels of the transcription factors AP-1, Egr-1, HSF-1, and NF-kappaB were transient but protein expression was noticeable at later time points. Our findings show that oxidative stress causes immediate upregulation of genes involved in a variety of cellular defense pathways. Complex interactions among them might determine the ultimate fate of the cell.