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1.
Lancet Diabetes Endocrinol ; 8(7): 582-593, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32559474

RESUMO

BACKGROUND: SGLT2 inhibition decreases albuminuria and reduces the risk of kidney disease progression in patients with type 2 diabetes. These benefits are unlikely to be mediated by improvements in glycaemic control alone. Therefore, we aimed to examine the kidney effects of the SGLT2 inhibitor dapagliflozin in patients with proteinuric kidney disease without diabetes. METHODS: DIAMOND was a randomised, double-blind, placebo-controlled crossover trial done at six hospitals in Canada, Malaysia, and the Netherlands. Eligible participants were adult patients (aged 18-75 years) with chronic kidney disease, without a diagnosis of diabetes, with a 24-h urinary protein excretion greater than 500 mg and less than or equal to 3500 mg and an estimated glomerular filtration rate (eGFR) of at least 25 mL/min per 1·73 m2, and who were on stable renin-angiotensin system blockade. Participants were randomly assigned (1:1) to receive placebo and then dapagliflozin 10 mg per day or vice versa. Each treatment period lasted 6 weeks with a 6-week washout period in between. Participants, investigators, and study personnel were masked to assignment throughout the trial and analysis. The primary outcome was percentage change from baseline in 24-h proteinuria during dapagliflozin treatment relative to placebo. Secondary outcomes were changes in measured GFR (mGFR; via iohexol clearance), bodyweight, blood pressure, and concentrations of neurohormonal biomarkers. Analyses were done in accordance with the intention-to-treat principle. This study is registered with ClinicalTrials.gov, NCT03190694. FINDINGS: Between Nov 22, 2017, and April 5, 2019, 58 patients were screened, of whom 53 (mean age 51 years [SD 13]; 32% women) were randomly assigned (27 received dapagliflozin then placebo and 26 received placebo then dapagliflozin). One patient discontinued during the first treatment period. All patients were included in the analysis. Mean baseline mGFR was 58·3 mL/min per 1·73 m2 (SD 23), median proteinuria was 1110 mg per 24 h (IQR 730-1560), and mean HbA1c was 5·6% (SD 0·4). The difference in mean proteinuria change from baseline between dapagliflozin and placebo was 0·9% (95% CI -16·6 to 22·1; p=0·93). Compared with placebo, mGFR was changed with dapagliflozin treatment by -6·6 mL/min per 1·73 m2 (-9·0 to -4·2; p<0·0001) at week 6. This reduction was fully reversible within 6 weeks after dapagliflozin discontinuation. Compared with placebo, bodyweight was reduced by 1·5 kg (0·03-3·0; p=0·046) with dapagliflozin; changes in systolic and diastolic blood pressure and concentrations of neurohormonal biomarkers did not differ significantly between dapagliflozin and placebo treatment. The numbers of patients who had one or more adverse events during dapagliflozin treatment (17 [32%] of 53) and during placebo treatment (13 [25%] of 52) were similar. No hypoglycaemic events were reported and no deaths occurred. INTERPRETATION: 6-week treatment with dapagliflozin did not affect proteinuria in patients with chronic kidney disease without diabetes, but did induce an acute and reversible decline in mGFR and a reduction in bodyweight. Long-term clinical trials are underway to determine whether SGLT2 inhibitors can safely reduce the rate of major clinical kidney outcomes in patients with chronic kidney disease with and without diabetes. FUNDING: AstraZeneca.

2.
JAMA ; 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32219386

RESUMO

Importance: Additional treatments are needed for heart failure with reduced ejection fraction (HFrEF). Sodium-glucose cotransporter 2 (SGLT2) inhibitors may be an effective treatment for patients with HFrEF, even those without diabetes. Objective: To evaluate the effects of dapagliflozin in patients with HFrEF with and without diabetes. Design, Setting, and Participants: Exploratory analysis of a phase 3 randomized trial conducted at 410 sites in 20 countries. Patients with New York Heart Association classification II to IV with an ejection fraction less than or equal to 40% and elevated plasma N-terminal pro B-type natriuretic peptide were enrolled between February 15, 2017, and August 17, 2018, with final follow-up on June 6, 2019. Interventions: Addition of once-daily 10 mg of dapagliflozin or placebo to recommended therapy. Main Outcomes and Measures: The primary outcome was the composite of an episode of worsening heart failure or cardiovascular death. This outcome was analyzed by baseline diabetes status and, in patients without diabetes, by glycated hemoglobin level less than 5.7% vs greater than or equal to 5.7%. Results: Among 4744 patients randomized (mean age, 66 years; 1109 [23%] women; 2605 [55%] without diabetes), 4742 completed the trial. Among participants without diabetes, the primary outcome occurred in 171 of 1298 (13.2%) in the dapagliflozin group and 231 of 1307 (17.7%) in the placebo group (hazard ratio, 0.73 [95% CI, 0.60-0.88]). In patients with diabetes, the primary outcome occurred in 215 of 1075 (20.0%) in the dapagliflozin group and 271 of 1064 (25.5%) in the placebo group (hazard ratio, 0.75 [95% CI, 0.63-0.90]) (P value for interaction = .80). Among patients without diabetes and a glycated hemoglobin level less than 5.7%, the primary outcome occurred in 53 of 438 patients (12.1%) in the dapagliflozin group and 71 of 419 (16.9%) in the placebo group (hazard ratio, 0.67 [95% CI, 0.47-0.96]). In patients with a glycated hemoglobin of at least 5.7%, the primary outcome occurred in 118 of 860 patients (13.7%) in the dapagliflozin group and 160 of 888 (18.0%) in the placebo group (hazard ratio, 0.74 [95% CI, 0.59-0.94]) (P value for interaction = .72). Volume depletion was reported as an adverse event in 7.3% of patients in the dapagliflozin group and 6.1% in the placebo group among patients without diabetes and in 7.8% of patients in the dapagliflozin group and 7.8% in the placebo group among patients with diabetes. A kidney adverse event was reported in 4.8% of patients in the dapagliflozin group and 6.0% in the placebo group among patients without diabetes and in 8.5% of patients in the dapagliflozin group and 8.7% in the placebo group among patients with diabetes. Conclusions and Relevance: In this exploratory analysis of a randomized trial of patients with HFrEF, dapagliflozin compared with placebo, when added to recommended therapy, significantly reduced the risk of worsening heart failure or cardiovascular death independently of diabetes status. Trial Registration: ClinicalTrials.gov Identifier: NCT03036124.

3.
Diabetes Obes Metab ; 22(7): 1157-1166, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32115853

RESUMO

AIM: To investigate which metabolic pathways are targeted by the sodium-glucose co-transporter-2 inhibitor dapagliflozin to explore the molecular processes involved in its renal protective effects. METHODS: An unbiased mass spectrometry plasma metabolomics assay was performed on baseline and follow-up (week 12) samples from the EFFECT II trial in patients with type 2 diabetes with non-alcoholic fatty liver disease receiving dapagliflozin 10 mg/day (n = 19) or placebo (n = 6). Transcriptomic signatures from tubular compartments were identified from kidney biopsies collected from patients with diabetic kidney disease (DKD) (n = 17) and healthy controls (n = 30) from the European Renal cDNA Biobank. Serum metabolites that significantly changed after 12 weeks of dapagliflozin were mapped to a metabolite-protein interaction network. These proteins were then linked with intra-renal transcripts that were associated with DKD or estimated glomerular filtration rate (eGFR). The impacted metabolites and their protein-coding transcripts were analysed for enriched pathways. RESULTS: Of all measured (n = 812) metabolites, 108 changed (P < 0.05) during dapagliflozin treatment and 74 could be linked to 367 unique proteins/genes. Intra-renal mRNA expression analysis of the genes encoding the metabolite-associated proteins using kidney biopsies resulted in 105 genes that were significantly associated with eGFR in patients with DKD, and 135 genes that were differentially expressed between patients with DKD and controls. The combination of metabolites and transcripts identified four enriched pathways that were affected by dapagliflozin and associated with eGFR: glycine degradation (mitochondrial function), TCA cycle II (energy metabolism), L-carnitine biosynthesis (energy metabolism) and superpathway of citrulline metabolism (nitric oxide synthase and endothelial function). CONCLUSION: The observed molecular pathways targeted by dapagliflozin and associated with DKD suggest that modifying molecular processes related to energy metabolism, mitochondrial function and endothelial function may contribute to its renal protective effect.

4.
CPT Pharmacometrics Syst Pharmacol ; 9(4): 222-229, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32064793

RESUMO

The aim of this research was to differentiate dapagliflozin, empagliflozin, and canagliflozin based on their capacity to inhibit sodium-glucose cotransporter (SGLT) 1 and 2 in patients with type 2 diabetes using a previously developed quantitative systems pharmacology model of renal glucose filtration, reabsorption, and excretion. The analysis was based on pooled, mean study-level data on 24-hour urinary glucose excretion, average daily plasma glucose, and estimated glomerular filtration rate collected from phase I and II clinical trials of SGLT2 inhibitors. Variations in filtered glucose across clinical studies were shown to drive the apparent differences in the glucosuria dose-response relationships among the gliflozins. A normalized dose-response analysis demonstrated similarity of dapagliflozin and empagliflozin, but not canagliflozin. At approved doses, SGLT1 inhibition by canagliflozin but not dapagliflozin or empagliflozin contributed to ~ 10% of daily urinary glucose excretion.

5.
Clin Transl Sci ; 13(2): 275-283, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31584739

RESUMO

Excessive activation of the mineralocorticoid receptor (MR) underlies the pathophysiology of heart failure and chronic kidney disease. Hyperkalemia risk limits the therapeutic use of conventional MR antagonists. AZD9977 is a nonsteroidal, selective MR modulator that may protect nonepithelial tissues without disturbing electrolyte balance. This phase I study investigated the safety, tolerability, pharmacokinetics, and pharmacodynamics of multiple oral doses of AZD9977 in healthy volunteers. Twenty-seven male participants aged 23-45 years were randomized 3:1 to receive oral AZD9977 or placebo for 8 days (with twice-daily dosing on days 2-7), in dose cohorts of 50, 150, and 300 mg (AZD9977, n = 6 per cohort; placebo, n = 3 per cohort). Adverse events occurred in 4 of 18 participants receiving AZD9977 (22.2%) and 6 of 9 receiving placebo (66.7%), all of mild or moderate severity; none were serious or led to withdrawal. AZD9977 was rapidly absorbed, with median time of maximum concentration of 0.50-0.84 hours across dose groups. Area under the curve and maximum concentration were approximately dose proportional but elimination and accumulation terminal half-life increased with dose. Steady-state was reached after 3-4 days, with dose-dependent accumulation of 1.2-1.7-fold. Renal clearance was 5.9-6.5 L/hour and 24-37% of AZD9977 was excreted in the urine. Serum aldosterone levels increased dose dependently from days -1 to 7 in participants receiving AZD9977, but serum potassium levels and urinary electrolyte excretion were unchanged. AZD9977 was generally well-tolerated with no safety concerns. Exploratory outcomes suggested reduced hyperkalemia risk compared with MR antagonists. These findings support further clinical development of AZD9977.

6.
Diabetes Obes Metab ; 21(12): 2684-2693, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31423699

RESUMO

AIM: To develop a quantitative drug-disease systems model to investigate the paradox that sodium-glucose co-transporter (SGLT)2 is responsible for >80% of proximal tubule glucose reabsorption, yet SGLT2 inhibitor treatment results in only 30% to 50% less reabsorption in patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: A physiologically based four-compartment model of renal glucose filtration, reabsorption and excretion via SGLT1 and SGLT2 was developed as a system of ordinary differential equations using R/IQRtools. SGLT2 inhibitor pharmacokinetics and pharmacodynamics were estimated from published concentration-time profiles in plasma and urine and from urinary glucose excretion (UGE) in healthy people and people with T2DM. RESULTS: The final model showed that higher renal glucose reabsorption in people with T2DM versus healthy people was associated with 54% and 28% greater transporter capacity for SGLT1 and SGLT2, respectively. Additionally, the analysis showed that UGE is highly dependent on mean plasma glucose and estimated glomerular filtration rate (eGFR) and that their consideration is critical for interpreting clinical UGE findings. CONCLUSIONS: Quantitative drug-disease system modelling revealed mechanistic differences in renal glucose reabsorption and UGE between healthy people and those with T2DM, and clearly showed that SGLT2 inhibition significantly increased glucose available to SGLT1 downstream in the tubule. Importantly, we found that the findings of lower than expected UGE with SGLT2 inhibition are explained by the shift to SGLT1, which recovered additional glucose (~30% of total).

7.
Diabetes Obes Metab ; 21(12): 2667-2673, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31407856

RESUMO

AIMS: To compare the effects of the sodium-glucose co-transporter-2 (SGLT2) inhibitor dapagliflozin on estimated (ePV) and measured plasma volume (mPV) and to characterize the effects of dapagliflozin on ePV in a broad population of patients with type 2 diabetes. MATERIALS AND METHODS: The Strauss formula was used to calculate changes in ePV. Change in plasma volume measured with 125 I-human serum albumin (mPV) was compared with change in ePV in 10 patients with type 2 diabetes randomized to dapagliflozin 10 mg/d or placebo. Subsequently, changes in ePV were measured in a pooled database of 13 phase 2b/3 placebo-controlled clinical trials involving 4533 patients with type 2 diabetes who were randomized to dapagliflozin 10 mg daily or matched placebo. RESULTS: The median change in ePV was similar to the median change in mPV (-9.4% and -9.0%) during dapagliflozin treatment. In the pooled analysis of clinical trials, dapagliflozin decreased ePV by 9.6% (95% confidence interval 9.0 to 10.2) compared to placebo after 24 weeks. This effect was consistent in various patient subgroups, including subgroups with or without diuretic use or established cardiovascular disease. CONCLUSIONS: ePV may be used as a proxy to assess changes in plasma volume during dapagliflozin treatment. Dapagliflozin consistently decreased ePV compared to placebo in a broad population of patients with type 2 diabetes.

8.
J Pharmacol Exp Ther ; 368(2): 255-261, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30482795

RESUMO

Fewer new medicines have become available to patients during the last decades. Clinical efficacy failures in late-phase development have been identified as a common cause of this decline. Improved ways to ensure early selection of the right drug targets when it comes to efficacy is therefore a highly desirable goal. The aim of this work was to develop a strategy to facilitate selection of novel targets already in the discovery phase that later on in clinical development would demonstrate efficacy. A cross-functional team at AstraZeneca with extensive experience in drug discovery and development participated in several workshops to identify the critical elements that contribute to building human target validation [(HTV); the relevance of the target from a human perspective]. The elements were consolidated into a 10-point HTV classification system that was ranked from lowest to highest in terms of perceived impact on future clinical efficacy. Using 50 years of legacy research and development data, the ability of the 10-point HTV classification to predict future clinical efficacy was evaluated. Drug targets were classified as having low, medium, or high HTV at the time of candidate drug selection. Comparing this HTV classification with later clinical development efficacy data showed that HTV classification was highly predictive of future clinical efficacy success. This new strategy for HTV assessment provides a novel approach to early prediction of clinical efficacy and a better understanding of portfolio risk.


Assuntos
Sistemas de Liberação de Medicamentos/classificação , Sistemas de Liberação de Medicamentos/tendências , Desenvolvimento de Medicamentos/classificação , Desenvolvimento de Medicamentos/tendências , Sistemas de Liberação de Medicamentos/métodos , Desenvolvimento de Medicamentos/métodos , Previsões , Humanos , Reprodutibilidade dos Testes , Resultado do Tratamento
9.
Nephrol Dial Transplant ; 34(2): 339-346, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29617976

RESUMO

Background: Elevated serum fibroblast growth factor 23 (FGF23) is strongly associated with cardiovascular risk and mortality. Tenapanor, an inhibitor of gastrointestinal sodium/hydrogen exchanger isoform 3, decreased serum phosphate in a randomized, double-blind, placebo-controlled Phase 2 trial (ClinicalTrials.gov identifier NCT02081534) of patients receiving hemodialysis with hyperphosphatemia. Here, we report a secondary analysis of effects on serum FGF23 during that study. Methods: After 1-3 weeks of washout of phosphate binders, 162 patients were randomized to receive 4 weeks of treatment with placebo or one of six tenapanor regimens (3 or 30 mg once daily, or 1, 3, 10 or 30 mg twice daily). Intact FGF23 concentrations were determined from serum samples collected at screening, post-washout and end of treatment, assayed in duplicate in a single batch at the end of the study. Results: After phosphate-binder washout, serum FGF23 concentrations increased in all groups [range of geometric means: 1430-2605 pg/mL before, to 2601-6294 pg/mL after washout (P < 0.001 for all patients analyzed as a single group)]. Serum FGF23 concentrations subsequently decreased in tenapanor-treated patients (2030-3563 pg/mL), whereas they increased further in placebo-treated patients (6930 pg/mL). In an analysis of covariance, FGF23 decreased by 9.1-27.9% in tenapanor-treated patients and increased by 21.9% in placebo-treated patients (P ≤ 0.001-0.04). Conclusions: Following a marked increase in serum FGF23 in response to withdrawal of phosphate binders, tenapanor significantly decreased serum FGF23 in patients receiving hemodialysis with hyperphosphatemia. Further studies are required to explore the long-term effects of controlling FGF23 with tenapanor.


Assuntos
Fatores de Crescimento de Fibroblastos/sangue , Hiperfosfatemia/tratamento farmacológico , Isoquinolinas/uso terapêutico , Falência Renal Crônica/tratamento farmacológico , Diálise Renal/métodos , Sulfonamidas/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Hiperfosfatemia/complicações , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Fosfatos/sangue , Diálise Renal/efeitos adversos
10.
Sci Transl Med ; 10(456)2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30158152

RESUMO

Hyperphosphatemia is common in patients with chronic kidney disease and is increasingly associated with poor clinical outcomes. Current management of hyperphosphatemia with dietary restriction and oral phosphate binders often proves inadequate. Tenapanor, a minimally absorbed, small-molecule inhibitor of the sodium/hydrogen exchanger isoform 3 (NHE3), acts locally in the gastrointestinal tract to inhibit sodium absorption. Because tenapanor also reduces intestinal phosphate absorption, it may have potential as a therapy for hyperphosphatemia. We investigated the mechanism by which tenapanor reduces gastrointestinal phosphate uptake, using in vivo studies in rodents and translational experiments on human small intestinal stem cell-derived enteroid monolayers to model ion transport physiology. We found that tenapanor produces its effect by modulating tight junctions, which increases transepithelial electrical resistance (TEER) and reduces permeability to phosphate, reducing paracellular phosphate absorption. NHE3-deficient monolayers mimicked the phosphate phenotype of tenapanor treatment, and tenapanor did not affect TEER or phosphate flux in the absence of NHE3. Tenapanor also prevents active transcellular phosphate absorption compensation by decreasing the expression of NaPi2b, the major active intestinal phosphate transporter. In healthy human volunteers, tenapanor (15 mg, given twice daily for 4 days) increased stool phosphorus and decreased urinary phosphorus excretion. We determined that tenapanor reduces intestinal phosphate absorption predominantly through reduction of passive paracellular phosphate flux, an effect mediated exclusively via on-target NHE3 inhibition.


Assuntos
Permeabilidade da Membrana Celular/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Isoquinolinas/farmacologia , Fosfatos/metabolismo , Trocador 3 de Sódio-Hidrogênio/antagonistas & inibidores , Sulfonamidas/farmacologia , Adulto , Idoso , Animais , Sequência de Bases , Células Cultivadas , Impedância Elétrica , Epitélio/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal/efeitos dos fármacos , Íons/urina , Masculino , Camundongos , Pessoa de Meia-Idade , Potássio/metabolismo , Prótons , Ratos , Sódio/metabolismo , Trocador 3 de Sódio-Hidrogênio/metabolismo , Proteínas de Junções Íntimas/metabolismo , Adulto Jovem
11.
Am J Physiol Renal Physiol ; 315(5): F1295-F1306, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30019930

RESUMO

The mechanisms of cardiovascular and renal protection observed in clinical trials of sodium-glucose cotransporter 2 (SGLT2) inhibitors (SGLT2i) are incompletely understood and likely multifactorial, including natriuretic, diuretic, and antihypertensive effects, glomerular pressure reduction, and lowering of plasma and interstitial fluid volume. To quantitatively evaluate the contribution of proposed SGLT2i mechanisms of action on changes in renal hemodynamics and volume status, we coupled a mathematical model of renal function and volume homeostasis with clinical data in healthy subjects administered 10 mg of dapagliflozin once daily. The minimum set of mechanisms necessary to reproduce observed clinical responses (urinary sodium and water excretion, serum creatinine and sodium) was determined, and important unobserved physiological variables (glomerular pressure, blood and interstitial fluid volume) were then simulated. We further simulated the response to SGLT2i in diabetic virtual patients with and without renal impairment. Multiple mechanisms were required to explain the observed response: 1) direct inhibition of sodium and glucose reabsorption through SGLT2, 2) SGLT2-driven inhibition of Na+/H+ exchanger 3 sodium reabsorption, and 3) osmotic diuresis coupled with peripheral sodium storage. The model also showed that the consequences of these mechanisms include lowering of glomerular pressure, reduction of blood and interstitial fluid volume, and mild blood pressure reduction, in agreement with clinical observations. The simulations suggest that these effects are more significant in diabetic patients than healthy subjects and that while glucose excretion may diminish with renal impairment, improvements in glomerular pressure and blood volume are not diminished at lower glomerular filtration rate, suggesting that cardiorenal benefits of SGLT2i may be sustained in renally impaired patients.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Sistema Cardiovascular/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Rim/efeitos dos fármacos , Modelos Cardiovasculares , Insuficiência Renal Crônica/tratamento farmacológico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Transportador 2 de Glucose-Sódio/metabolismo , Sistema Cardiovascular/metabolismo , Sistema Cardiovascular/fisiopatologia , Simulação por Computador , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Diurese/efeitos dos fármacos , Taxa de Filtração Glomerular/efeitos dos fármacos , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Rim/metabolismo , Rim/fisiopatologia , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/fisiopatologia , Reabsorção Renal/efeitos dos fármacos , Transportador 1 de Glucose-Sódio/metabolismo , Resultado do Tratamento
12.
BMC Nephrol ; 19(1): 146, 2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29929484

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is highly prevalent but identification of patients at high risk for fast CKD progression before reaching end-stage renal disease in the short-term has been challenging. Whether factors associated with fast progression vary by diabetes status is also not well understood. We examined a large community-based cohort of adults with CKD to identify predictors of fast progression during the first 2 years of follow-up in the presence or absence of diabetes mellitus. METHODS: Within a large integrated healthcare delivery system in northern California, we identified adults with estimated glomerular filtration rate (eGFR) 30-59 ml/min/1.73 m2 by CKD-EPI equation between 2008 and 2010 who had no previous dialysis or renal transplant, who had outpatient serum creatinine values spaced 10-14 months apart and who did not initiate renal replacement therapy, die or disenroll during the first 2 years of follow-up. Through 2012, we calculated the annual rate of change in eGFR and classified patients as fast progressors if they lost > 4 ml/min/1.73 m2 per year. We used multivariable logistic regression to identify patient characteristics that were independently associated with fast CKD progression stratified by diabetes status. RESULTS: We identified 36,195 eligible adults with eGFR 30-59 ml/min/1.73 m2 and mean age 73 years, 55% women, 11% black, 12% Asian/Pacific Islander and 36% with diabetes mellitus. During 24-month follow-up, fast progression of CKD occurred in 23.0% of patients with diabetes vs. 15.3% of patients without diabetes. Multivariable predictors of fast CKD progression that were similar by diabetes status included proteinuria, age ≥ 80 years, heart failure, anemia and higher systolic blood pressure. Age 70-79 years, prior ischemic stroke, current or former smoking and lower HDL cholesterol level were also predictive in patients without diabetes, while age 18-49 years was additionally predictive in those with diabetes. CONCLUSIONS: In a large, contemporary population of adults with eGFR 30-59 ml/min/1.73 m2, accelerated progression of kidney dysfunction within 2 years affected ~ 1 in 4 patients with diabetes and ~ 1 in 7 without diabetes. Regardless of diabetes status, the strongest independent predictors of fast CKD progression included proteinuria, elevated systolic blood pressure, heart failure and anemia.


Assuntos
Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Progressão da Doença , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Diabetes Mellitus/fisiopatologia , Feminino , Seguimentos , Taxa de Filtração Glomerular/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Insuficiência Renal Crônica/fisiopatologia
13.
Diabetes Obes Metab ; 20(3): 479-487, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29024278

RESUMO

The effect of a sodium glucose cotransporter 2 inhibitor (SGLT2i) in reducing heart failure hospitalization in the EMPA-REG OUTCOMES trial has raised the possibility of using these agents to treat established heart failure. We hypothesize that osmotic diuresis induced by SGLT2 inhibition, a distinctly different diuretic mechanism than that of other diuretic classes, results in greater electrolyte-free water clearance and, ultimately, in greater fluid clearance from the interstitial fluid (IF) space than from the circulation, potentially resulting in congestion relief with minimal impact on blood volume, arterial filling and organ perfusion. We utilize a mathematical model to illustrate that electrolyte-free water clearance results in a greater reduction in IF volume compared to blood volume, and that this difference may be mediated by peripheral sequestration of osmotically inactive sodium. By coupling the model with data on plasma and urinary sodium and water in healthy subjects who received either the SGLT2i dapagliflozin or loop diuretic bumetanide, we predict that dapagliflozin produces a 2-fold greater reduction in IF volume compared to blood volume, while the reduction in IF volume with bumetanide is only 78% of the reduction in blood volume. Heart failure is characterized by excess fluid accumulation, in both the vascular compartment and interstitial space, yet many heart failure patients have arterial underfilling because of low cardiac output, which may be aggravated by conventional diuretic treatment. Thus, we hypothesize that, by reducing IF volume to a greater extent than blood volume, SGLT2 inhibitors might provide better control of congestion without reducing arterial filling and perfusion.


Assuntos
Compostos Benzidrílicos/farmacologia , Bumetanida/farmacologia , Diuréticos/farmacologia , Glucosídeos/farmacologia , Insuficiência Cardíaca/prevenção & controle , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Adulto , Compostos Benzidrílicos/administração & dosagem , Volume Sanguíneo/efeitos dos fármacos , Bumetanida/administração & dosagem , Diurese/efeitos dos fármacos , Combinação de Medicamentos , Interações Medicamentosas , Feminino , Glucosídeos/administração & dosagem , Insuficiência Cardíaca/urina , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Sódio/urina , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Desequilíbrio Hidroeletrolítico/fisiopatologia , Adulto Jovem
14.
Am J Physiol Gastrointest Liver Physiol ; 313(2): G129-G137, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28495802

RESUMO

Na+/H+ exchanger NHE3 mediates the majority of intestinal and renal electroneutral sodium absorption. Dysfunction of NHE3 is associated with a variety of diarrheal diseases. We previously reported that the NHE3 gene (SLC9A3) has more than 400 single-nucleotide polymorphisms (SNPs) but few nonsynonymous polymorphisms. Among the latter, one polymorphism (rs2247114-G>A), which causes a substitution from arginine to cysteine at amino acid position 799 (p.R799C), is common in Asian populations. To improve our understanding of the population distribution and potential clinical significance of the NHE3-799C variant, we investigated the frequency of this polymorphism in different ethnic groups using bioinformatics analyses and in a cohort of Japanese patients with cardiovascular or renal disease. We also characterized the function of human NHE3-799C and its sensitivity to regulatory ligands in an in vitro model. NHE3-799C had an allele frequency of 29.5-57.6% in Asian populations, 11.1-23.6% in European populations, and 10.2-22.7% in African populations. PS120/FLAG-NHERF2 fibroblasts stably expressing NHE3-799C had lower total protein expression but a higher percentage of surface expression than those expressing NHE3-799R. NHE3-799C had similar basal activity to NHE3-799R and was similarly stimulated or inhibited, by serum or forskolin, respectively. Tenapanor, a small-molecule NHE3 inhibitor, dose-dependently inhibited NHE3-799R and NHE3-799C activities. The IC50 values of tenapanor for NHE3-799C and NHE3-799R were significantly different, but both were in the nanomolar range. These results suggest that NHE3-799C is a common variant enriched in Asian populations, is not associated with compromised function or abnormal regulation, and is unlikely to contribute to clinical disease.NEW & NOTEWORTHY This study reports results on the functional significance of human NHE3-799C under basal conditions and in response to regulatory ligands, including a novel NHE3 inhibitor called tenapanor. We demonstrate that NHE3-799C is a common variant of NHE3 that is enriched in Asian populations; however, in contrast to our previous studies using rabbit NHE3, its presence seems to have limited clinical significance in humans and is not associated with compromised function or abnormal transport regulation.


Assuntos
Alelos , Frequência do Gene , Polimorfismo de Nucleotídeo Único , Trocadores de Sódio-Hidrogênio/genética , Grupo com Ancestrais do Continente Asiático/genética , Doenças Cardiovasculares/genética , Biologia Computacional , Grupo com Ancestrais do Continente Europeu/genética , Genótipo , Humanos , Nefropatias/genética , Mutação , Trocador 3 de Sódio-Hidrogênio
15.
Clin J Am Soc Nephrol ; 12(5): 751-759, 2017 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-28302903

RESUMO

BACKGROUND AND OBJECTIVE: Sodium glucose cotransporter 2 inhibition with dapagliflozin decreases hemoglobin A1c (HbA1c), body weight, BP, and albuminuria (urinary albumin-to-creatinine ratio). Dapagliflozin also modestly increases hematocrit, likely related to osmotic diuresis/natriuresis. Prior studies suggest that the HbA1c-lowering effects of dapagliflozin attenuate at lower eGFR. However, effects on other cardiovascular risk factors at different eGFR levels are incompletely understood. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This pooled analysis of 11 phase 3 clinical trials assessed changes in HbA1c, body weight, BP, hematocrit, and urinary albumin-to-creatinine ratio with placebo (n=2178) or dapagliflozin 10 mg (n=2226) over 24 weeks in patients with type 2 diabetes according to baseline eGFR (eGFR≥45 to <60 ml/min per 1.73 m2, eGFR≥60 to <90 ml/min per 1.73 m2, and eGFR≥90 ml/min per 1.73 m2). RESULTS: Compared with placebo, reductions in HbA1c with dapagliflozin were 0.6%, 0.5%, and 0.3%, respectively, for each consecutive lower eGFR subgroup (P value interaction <0.001). Effects of dapagliflozin on hematocrit, body weight, and BP were similar regardless of baseline eGFR, suggesting that effects potentially related to volume and natriuresis are eGFR independent. Moreover, among individuals with baseline urinary albumin-to-creatinine ratio ≥30 mg/g, placebo-adjusted reductions in urinary albumin-to-creatinine ratio were larger in the lowest eGFR subgroup (P value interaction <0.001). Adverse events occurred more frequently in the lowest eGFR subgroup; this was true for both dapagliflozin- and placebo-treated patients. CONCLUSIONS: The HbA1c-lowering effects of dapagliflozin decrease as renal function declines. However, dapagliflozin consistently decreases body weight, BP, and urinary albumin-to-creatinine ratio regardless of eGFR. These effects in conjunction with the finding of similar effects on hematocrit, a proxy for volume contraction, suggest that the effects of dapagliflozin are partly mediated via nonglucosuric-dependent mechanisms.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Taxa de Filtração Glomerular , Glucosídeos/uso terapêutico , Hipoglicemiantes/uso terapêutico , Túbulos Renais Proximais/efeitos dos fármacos , Inibidores do Transportador 2 de Sódio-Glicose , Idoso , Albuminúria/epidemiologia , Albuminúria/fisiopatologia , Albuminúria/prevenção & controle , Compostos Benzidrílicos/efeitos adversos , Biomarcadores/sangue , Biomarcadores/urina , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Doenças Cardiovasculares/epidemiologia , Ensaios Clínicos Fase III como Assunto , Creatinina/urina , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Glucosídeos/efeitos adversos , Hemoglobina A Glicada/metabolismo , Hemoglobinas/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Proteção , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Transportador 2 de Glucose-Sódio/metabolismo , Resultado do Tratamento
16.
PLoS One ; 11(12): e0167965, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27941994

RESUMO

The G-protein coupled receptor 55 (GPR55) is activated by cannabinoids and non-cannabinoid molecules and has been speculated to play a modulatory role in a large variety of physiological and pathological processes, including in metabolically perturbed states. We therefore generated male mice deficient in the gene coding for the cannabinoid/lysophosphatidylinositol (LPI) receptor Gpr55 and characterized them under normal dietary conditions as well as during high energy dense diet feeding followed by challenge with the CB1 receptor antagonist/GPR55 agonist rimonabant. Gpr55 deficient male mice (Gpr55 KO) were phenotypically indistinguishable from their wild type (WT) siblings for the most part. However, Gpr55 KO animals displayed an intriguing nocturnal pattern of motor activity and energy expenditure (EE). During the initial 6 hours of the night, motor activity was significantly elevated without any significant effect observed in EE. Interestingly, during the last 6 hours of the night motor activity was similar but EE was significantly decreased in the Gpr55 KO mice. No significant difference in motor activity was detected during daytime, but EE was lower in the Gpr55 KO compared to WT mice. The aforementioned patterns were not associated with alterations in energy intake, daytime core body temperature, body weight (BW) or composition, although a non-significant tendency to increased adiposity was seen in Gpr55 KO compared to WT mice. Detailed analyses of daytime activity in the Open Field paradigm unveiled lower horizontal activity and rearing time for the Gpr55 KO mice. Moreover, the Gpr55 KO mice displayed significantly faster reaction time in the tail flick test, indicative of thermal hyperalgesia. The BW-decreasing effect of rimonabant in mice on long-term cafeteria diet did not differ between Gpr55 KO and WT mice. In conclusion, Gpr55 deficiency is associated with subtle effects on diurnal/nocturnal EE and motor activity behaviours but does not appear per se critically required for overall metabolism or behaviours.


Assuntos
Metabolismo Energético , Dor/metabolismo , Receptores de Canabinoides/metabolismo , Animais , Comportamento Animal , Temperatura Corporal , Calorimetria , Antagonistas de Receptores de Canabinoides/metabolismo , Dieta Hiperlipídica , Metabolismo Energético/genética , Deleção de Genes , Estudos Longitudinais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora/genética , Dor/genética , Piperidinas/metabolismo , Pirazóis/metabolismo , Receptores de Canabinoides/deficiência , Receptores de Canabinoides/genética , Rimonabanto , Sensação Térmica/genética
17.
Clin J Am Soc Nephrol ; 11(9): 1597-605, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27340281

RESUMO

BACKGROUND AND OBJECTIVES: Interdialytic weight gain in patients on hemodialysis is associated with adverse cardiovascular outcomes and increased mortality. The degree of interdialytic weight gain is influenced by sodium intake. We evaluated the effects of tenapanor (AZD1722 and RDX5791), a minimally systemically available inhibitor of the sodium/hydrogen exchanger isoform 3, on interdialytic weight gain in patients with CKD stage 5D treated with hemodialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This phase 2, randomized, double-blind study (NCT01764854; conducted January to September of 2013) enrolled adults on maintenance hemodialysis with interdialytic weight gain ≥3.0% of postdialysis weight and ≥2 kg. Patients were randomly assigned (1:1) to receive tenapanor or placebo. The primary end point was change in mean interdialytic weight gain (percentage of baseline postdialysis weight) from baseline (mean across a 2-week run-in period) to week 4. In a subgroup of inpatients, 24-hour stool sodium and stool weight were assessed for 1 week. RESULTS: Sixteen patients received 1 week of inpatient treatment (tenapanor, eight; placebo, eight), and 72 patients received 4 weeks of treatment in an outpatient setting (tenapanor, 37; placebo, 35; completers: tenapanor, 31; placebo, 33). In the outpatient cohort, no significant effect on interdialytic weight gain was detected; least squares mean changes in relative interdialytic weight gain from baseline to week 4 were tenapanor, -0.26% (95% confidence interval, -0.57% to 0.06%) and placebo, -0.23% (95% confidence interval, -0.54% to 0.07%; P=0.46). During week 1 (inpatient cohort only), compared with placebo, tenapanor treatment resulted in higher stool sodium content (mean [±SD]: tenapanor, 36.6 [±21.8] mmol/d; placebo, 2.8 [±2.7] mmol/d; P<0.001) and higher stool weight (tenapanor, 172.5 [±68.1] g/d; placebo, 86.3 [±30.0] g/d; P<0.01). A similar safety profile was observed across treatment groups with the exception of diarrhea, which occurred more frequently with tenapanor treatment. CONCLUSIONS: Tenapanor treatment increased stool sodium and weight over placebo in patients undergoing hemodialysis. However, over 4 weeks of treatment, there was no difference in interdialytic weight gain between patients treated with tenapanor and those receiving placebo.


Assuntos
Isoquinolinas/farmacologia , Falência Renal Crônica/terapia , Trocador 3 de Sódio-Hidrogênio/antagonistas & inibidores , Sulfonamidas/farmacologia , Ganho de Peso/efeitos dos fármacos , Adulto , Idoso , Diarreia/induzido quimicamente , Método Duplo-Cego , Fezes/química , Feminino , Humanos , Isoquinolinas/efeitos adversos , Isoquinolinas/farmacocinética , Masculino , Pessoa de Meia-Idade , Diálise Renal , Sódio/análise , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética , Adulto Jovem
18.
Cardiovasc Diabetol ; 15: 36, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26892461

RESUMO

BACKGROUND: Patients with angina-like symptoms without myocardial perfusion scintigram (MPS)-verified abnormality may still be at risk for cardiovascular events. We hypothesized that insulin resistance could play a role in this population even without diagnosed diabetes. We further explored physiological and blood biomarkers, as well as global gene expression patterns that could be closely related to impaired glucose homeostasis to deepen our mechanistic understanding. METHODS: A total of 365 non-diabetic patients with suspected myocardial ischemia referred to MPS were enrolled and followed up regarding event-free survival with a median time of 5.1 years. All patients underwent endothelial function assessment by reactive hyperemic index (RHI) using EndoPAT and extensive biomarker analysis. Whole blood global gene expression pathway analysis was performed in a subset of patients. RESULTS: Homeostasis model assessment of insulin resistance (HOMA-IR) added independent prognostic value in patients without myocardial perfusion defects. In a multivariable analysis, HOMA-IR was inversely associated with low RHI. Furthermore, elevated HOMA-IR was associated with decreased levels of vascular endothelial growth factor D, stem cell factor and endocan as well as to increased level of interleukin-6. Global gene expression pathway analysis of whole blood cells showed that high HOMA-IR and impaired endothelial function were associated with upregulated pro-inflammatory pathways and down-regulated eukaryotic initiation factor-2 pathway. CONCLUSIONS: Insulin resistance measured by HOMA-IR is associated with endothelial dysfunction and confers independent prognostic information in non-diabetic patients with chest pain without myocardial perfusion defects. Increased systemic pro-inflammatory state and decreased levels of pro-angiogenic vascular growth factors may be important underlying molecular mechanisms.


Assuntos
Angina Pectoris/etiologia , Proteínas Angiogênicas/sangue , Doença da Artéria Coronariana/etiologia , Endotélio Vascular/fisiopatologia , Resistência à Insulina , Estado Pré-Diabético/complicações , Idoso , Angina Pectoris/sangue , Angina Pectoris/diagnóstico , Angina Pectoris/genética , Angina Pectoris/fisiopatologia , Proteínas Angiogênicas/genética , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/fisiopatologia , Intervalo Livre de Doença , Feminino , Regulação da Expressão Gênica , Humanos , Hiperemia/fisiopatologia , Mediadores da Inflamação/sangue , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estado Pré-Diabético/sangue , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/fisiopatologia , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores de Tempo , Vasodilatação
19.
Pharmacol Res Perspect ; 3(3): e00143, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26236485

RESUMO

The receptors mediating the hemodynamic responses to cannabinoids are not clearly defined due to the multifarious pharmacology of many commonly used cannabinoid ligands. While both CB1 and TRPV1 receptors are implicated, G protein-coupled receptor 55 (GPR55) may also mediate some of the hemodynamic effects of several atypical cannabinoid ligands. The present studies attempted to unravel the pharmacology underlying the in vivo hemodynamic responses to ACEA (CB1 agonist), O-1602 (GPR55 agonist), AM251 (CB1 antagonist), and cannabidiol (CBD; GPR55 antagonist). Agonist and antagonist profiles of each ligand were determined by ligand-induced GTPγS binding in membrane preparations expressing rat and mouse CB1 and GPR55 receptors. Blood pressure responses to ACEA and O-1602 were recorded in anesthetized and conscious mice (wild type, CB1 (-/-) and GPR55(-/-)) and rats in the absence and presence of AM251 and CBD. ACEA demonstrated GTPγS activation at both receptors, while O-1602 only activated GPR55. AM251 exhibited antagonist activity at CB1 and agonist activity at GPR55, while CBD demonstrated selective antagonist activity at GPR55. The depressor response to ACEA was blocked by AM251 and attenuated by CBD, while O-1602 did not induce a depressor response. AM251 caused a depressor response that was absent in GPR55(-/-) mice but enhanced by CBD, while CBD caused a small vasodepressor response that persisted in GPR55(-/-) mice. Our findings show that assessment of the pharmacological profile of receptor activation by cannabinoid ligands in in vitro studies alongside in vivo functional studies is essential to understand the role of cannabinoids in hemodynamic control.

20.
Curr Opin Nephrol Hypertens ; 24(5): 410-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26197202

RESUMO

PURPOSE OF REVIEW: Impaired sodium excretion in patients with chronic kidney disease (CKD) can drive fluid overload and hypertension and accelerate CKD progression. Diuretics reduce fluid overload but require residual kidney function to work. Adherence to dietary sodium restriction is generally poor. Here, we review an alternative pharmacologic strategy aimed at reducing sodium absorption from the gut. RECENT FINDINGS: Genetic studies implicate the sodium/hydrogen exchanger isoform 3 (NHE3) as the major absorptive sodium transporter. Pharmacologic inhibition of apically expressed gut NHE3 offers the potential of reducing sodium absorption and fluid overload independent of kidney function and with better safety than systemic drugs. Two small-molecule inhibitors of NHE3 (tenapanor and SAR218034) with minimal systemic exposure reduce urinary sodium and increase stool sodium in a dose-dependent manner in rodents, with similar results observed with tenapanor in humans. These molecules also reduce blood pressure in rat models of CKD (tenapanor) and hypertension (SAR218034). Clinical trials of tenapanor in patients with CKD-related disorders are ongoing. SUMMARY: Pharmacologic inhibition of gut NHE3 may be a viable strategy for managing sodium load in patients with CKD or with sodium-sensitive hypertension in general. Ongoing clinical trials will shed further light on the potential benefits of this approach.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/tratamento farmacológico , Insuficiência Renal Crônica/tratamento farmacológico , Sódio na Dieta/metabolismo , Sódio/metabolismo , Animais , Humanos , Mucosa Intestinal/metabolismo , Insuficiência Renal Crônica/metabolismo
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