eplerenone and Diabetic-Nephropathies

Diabetic nephropathy (DN), which is correlated with an increased risk of cardiovascular disease, significantly elevates the morbidity and mortality of patients with diabetes. Recently, the benefits of mineralocorticoid receptor antagonists in chronic kidney disease (CKD), such as their anti-inflammatory and anti-fibrotic properties, have been discovered. Thus, the present meta-analysis aimed to systematically assess the efficacy and safety of eplerenone treatment in patients with DN. Six electronic databases-PubMed, The Cochrane Library, Embase, Web of Science, CNKI (China National Knowledge Infrastructure), and CBM(Chinese BioMedical Literature Database)-were searched to retrieve randomized controlled trials that assessed eplerenone treatment in patients with DN and were published up to July 31, 2021. Eight randomized controlled trials involving 838 patients were included. Between the eplerenone treatment groups and controls, significant differences were identified in 24-h urine protein levels (mean difference [MD], -19.63 [95% CI, -23.73 to -15.53], P < 0.00001), microalbuminuria (MD, -7.75 [95% CI, -9.75 to -5.75], P < 0.00001), urinary albumin-creatinine ratio (MD, -48.29 [95% CI, -64.45 to -32.14], P < 0.00001), systolic blood pressure (SBP) (MD, -2.49 [95% CI, -4.48 to -0.50], P = 0.01), serum potassium levels (MD, 0.19 [95% CI, 0.13 to 0.24], P < 0.00001), and levels of the renal fibrosis indicator laminin (MD, -8.84 [95% CI, -11.93 to -5.75], P < 0.00001). However, for the effect of estimated glomerular filtration rate (MD, 1.74 [95% CI, -0.87 to 4.35], P = 0.19) and diastolic blood pressure (MD, -0.51 [95% CI, -1.58 to 0.57], P = 0.36), the differences between the two groups were not significant. In addition, no noticeable difference was identified in the adverse events of hyperkalemia and cough between them. These findings suggest that eplerenone exerts beneficial effects on DN by significantly reducing urinary albumin or protein excretion, SBP, and laminin levels, without increasing the incidence of hyperkalemia and other adverse events.

Topics: Albumins; Diabetes Mellitus; Diabetic Nephropathies; Eplerenone; Female; Humans; Hyperkalemia; Laminin; Male; Randomized Controlled Trials as Topic

Diabetic kidney disease (DKD) represents a leading cause of morbidity and mortality in subjects with diabetes and develops in more than one third of diabetic patients. Steroidal mineralocorticoid receptor antagonists (MRAs - eplerenone and spironolactone) reduce mortality in patients with heart failure with reduced ejection fraction (HFrEF). However, in clinical practice the use of steroidal MRAs is limited by the significant risk of hyperkalemia, especially in patients with impaired renal function. Finerenone, a novel nonsteroidal MRA, shows a higher selectivity and binding affinity for mineralocorticoid receptor (MR) compared to steroidal MRAs and has been shown to reduce chronic kidney disease (CKD) progression and cardiovascular mortality in patients with CKD and T2DM.. This review summarizes the current evidence on efficacy and safety of finerenone in the treatment of patients with CKD and T2DM, and discusses its mechanisms of action investigated in preclinical studies.. Pharmacological properties of finerenone and its unique tissue distribution are responsible for a lower risk of hyperkalemia. Therefore, finerenone represents a valuable therapeutic tool in patients with CKD/diabetic kidney disease (DKD). Recent studies have shown that finerenone delays the progression of CKD and reduce cardiovascular events in patients with DKD, highlighting its safety and efficacy in this high-risk population.

Topics: Diabetes Mellitus, Type 2; Diabetic Nephropathies; Eplerenone; Heart Failure; Humans; Hyperkalemia; Mineralocorticoid Receptor Antagonists; Naphthyridines; Receptors, Mineralocorticoid; Renal Insufficiency, Chronic; Spironolactone; Stroke Volume

Finerenone is a novel non-steroidal mineralocorticoid antagonist (MRA) recently approved for the treatment of chronic kidney disease (CKD) in people with type 2 diabetes (T2D). We aim to conduct a systematic review of finerenone to know the efficacy and safety of finerenone in CKD with or without T2D.. A systematic search in the electronic database of PubMed and Google Scholar was made from inception until September 09, 2022, using several MeSH keywords related to finerenone. Ongoing trials were additionally searched from ClinicalTrials.Gov.. Five phase 2 and three phase 3, randomized, double-blind, placebo- or active-controlled studies of finerenone have been published to date and several other randomized and real-world studies of finerenone are currently undergoing.. In short-term studies in patients with CKD and reduced ejection heart failure, with or without T2D, finerenone 20 mg appears to have a better renal outcome compared with spironolactone and a better mortality outcome compared with eplerenone, with significantly lesser hyperkalemia compared to both spironolactone and finerenone. In long-term studies in patients with CKD and T2D, finerenone 10/20 mg significantly reduces the progression of renal disease and reduced CV endpoints (especially heart failure hospitalization) compared to placebo. Finerenone has no effect on HbA1c, body weight, and sexual side effects including gynecomastia, and has only a modest effect on blood pressure. However, hyperkalemia leading to drug withdrawal was significantly higher with finerenone compared to placebo. Safety data in real-world settings is a pressing priority.

Topics: Diabetes Mellitus, Type 2; Diabetic Nephropathies; Eplerenone; Glycated Hemoglobin; Heart Failure; Humans; Hyperkalemia; Male; Mineralocorticoid Receptor Antagonists; Randomized Controlled Trials as Topic; Renal Insufficiency, Chronic; Spironolactone

Cardiovascular and renal diseases are one of the main health problems in all industrialized countries. Their incidence is constantly increasing due to the aging of the population and the greater prevalence of obesity and type 2 diabetes. Clinical evidence suggests that aldosterone and the activation of mineralocorticoid receptors (MR) have a role in the pathophysiology of cardiovascular and renal diseases. Moreover, clinical studies demonstrate the benefits of mineralocorticoid receptor antagonists (MRAs) on mortality and progression of heart and kidney disease. In addition to renal effects on body fluid homeostasis, aldosterone has multiple extrarenal effects including the induction of inflammation, vascular rigidity, collagen formation and stimulation of fibrosis. Given the fundamental role of MR activation in renal and cardiac fibrosis, effective and selective blocking of the signal with MRAs can be used in the clinical practice to prevent or slow down the progression of heart and kidney diseases. The aim of the present work is to review the role of MRAs in light of the new evidence as well as its potential use as an antifibrotic in chronic kidney disease (CKD). The initial clinical results suggest that MRAs are potentially useful in treating patients with chronic kidney disease, particularly in cases of diabetic nephropathy. We don't yet have efficacy and safety data on the progression of kidney disease up to the end stage (ESRD) and filling this gap represents an important target for future trials.

Topics: Aldosterone; Body Fluids; Cardiovascular Diseases; Clinical Trials as Topic; Cytokines; Diabetic Nephropathies; Eplerenone; Fibrosis; Heart; Heart Diseases; Homeostasis; Humans; Kidney; Mineralocorticoid Receptor Antagonists; Naphthyridines; Receptors, Mineralocorticoid; Renal Insufficiency, Chronic; Spironolactone

Current data highlight the pathological aspects of excess aldosterone in promoting glomerular hypertrophy, glomerulosclerosis, and proteinuria in diabetic kidney disease (DKD). The role of nonsteroidal mineralocorticoid receptor antagonists (MRAs) in DKD is being evaluated in ongoing clinical trials.. Recent studies demonstrate beneficial effects of adding MRAs to the treatment regimen of patients with type 2 diabetes with nephropathy. The MRAs spironolactone and eplerenone can protect against organ damage caused by elevated levels of serum aldosterone in patients with heart failure and DKD but are limited by their side effects, for example, hyperkalemia. Finerenone is more selective for the mineralocorticoid receptor than spironolactone and has greater affinity for the mineralocorticoid receptor than eplerenone. It reduces the concentration of aldosterone without causing significant elevation in serum potassium.. MRAs have a clear role in reducing albuminuria when used with other renin-angiotensin system blockers in DKD; however, hyperkalemia limits their use. This article provides an overview of clinical studies with a novel MRA, finerenone, and several nonsteroidal MRAs being studied for treatment in DKD.

Topics: Albuminuria; Clinical Trials as Topic; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Eplerenone; Humans; Mineralocorticoid Receptor Antagonists; Renin-Angiotensin System; Spironolactone

Characterization of mice with cell-specific deletion or overexpression of the mineralocorticoid receptor (MR) shed a new light on its role in health and disease. Pathophysiological MR activation contributes to a plethora of deleterious molecular mechanisms in the development of cardiorenal diseases like chronic kidney disease (CKD) and heart failure (HF). Accordingly, the available steroidal MR antagonists (MRAs) spironolactone (first generation MRA) and eplerenone (second generation MRA) have been shown to be effective in reducing cardiovascular (CV) mortality and morbidity in patients with chronic HF and a reduced left ventricular ejection fraction (HFrEF). However, they remain underutilized, in large part owing to the risk inducing severe adverse events including hyperkalemia and worsening of kidney function, particularly when given on top of inhibitors of the renin angiotensin system (RAS) to patients with concomitant kidney dysfunction. Novel, potent, and selective non-steroidal MRAs (third generation) were identified in drug discovery campaigns and a few entered clinical development recently. One of these is finerenone with different physicochemical, pharmacokinetics, and pharmacological properties in comparison with the steroidal MRAs. Available data from five clinical phase II trials with finerenone in more than 2,000 patients with HF and additional CKD and/or diabetes as well as in patients with diabetic kidney disease demonstrated that neither hyperkalemia nor reductions in kidney function were limiting factors to its use. Moreover, finerenone demonstrated a nominally improved outcome compared to eplerenone in a phase IIb trial with 1,066 patients with HFrEF and concomitant type 2 diabetes mellitus (T2DM) and/or CKD.

Topics: Animals; Cardio-Renal Syndrome; Diabetic Nephropathies; Endothelial Cells; Eplerenone; Fibroblasts; Heart Failure; Humans; Macrophages; Mineralocorticoid Receptor Antagonists; Muscle, Smooth, Vascular; Myocytes, Cardiac; Myocytes, Smooth Muscle; Naphthyridines; Receptors, Mineralocorticoid; Spironolactone; Stroke Volume

Blockade of the renin-angiotensin-aldosterone system (RAAS) is a standard therapeutic intervention in diabetic patients with chronic kidney disease (CKD). Concomitant mineralocorticoid receptor blockade has been studied as a novel approach to further slow down CKD progression. We used PubMed and EMBASE databases to search for relevant literature. We included in our review eight studies in patients of at least 18 years of age, with a diagnosis of type 1 or type 2 diabetes mellitus and diabetic nephropathy, under an angiotensin converting enzyme inhibitor (ACEI) and/or an angiotensin II receptor blocker (ARB) as standard treatment. A subset of patients in each study also received a mineralocorticoid receptor blocker (MRB) (either spironolactone or eplerenone) in addition to standard treatment. Combined treatment with a mineralocorticoid receptor blocker further reduced albuminuria by 23 to 61% compared with standard treatment. Estimated glomerular filtration rate values upon study completion slightly decreased under combined treatment. Blood pressure levels upon study completion were significantly lower with combined treatment in three studies. Hyperkalemia prevalence increased in patients under combined treatment raising dropout rate up to 17%. Therefore, combined treatment by an ACEI/ARB and a MRB may further decrease albuminuria in diabetic nephropathy. This effect may be due to the specific properties of the MRB treatment. Clinicians should regularly check potassium levels because of the increased risk of hyperkalemia. Available evidence should be confirmed by an adequately powered comparative trial of the standard treatment (ACEI or ARB) versus combined treatment by an ACEI/ARB and a MRB.

Topics: Albuminuria; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Diabetic Nephropathies; Drug Therapy, Combination; Eplerenone; Glomerular Filtration Rate; Humans; Hyperkalemia; Mineralocorticoid Receptor Antagonists; Renal Insufficiency, Chronic; Spironolactone; Treatment Outcome

Topics: Animals; Diabetic Nephropathies; Drug Design; Humans; Hypertension; Mineralocorticoid Receptor Antagonists; Receptors, Mineralocorticoid

Angiotensin-converting enzyme inhibitors (ACEI) combined with mineralocorticoid receptor antagonists were found to have a beneficial effect on patients with chronic kidney disease.. The aim of our clinical trial was to compare the antialbuminuric effect of ramipril monotherapy, eplerenone monotherapy and eplerenone/ramipril combination therapy in patients with stage 1 hypertension and type 2 diabetes mellitus.. In a single-blind, randomized clinical trial, 75 hypertensive patients (stage 1 hypertension) with type 2 diabetes mellitus and microalbuminuria were randomized in a 1:1:1 ratio to 1 of 3 groups: ramipril 10 mg monotherapy (25 patients), eplerenone 50 mg monotherapy (25 patients) and combination therapy of eplerenone/ramipril 50/10 mg (25 patients) through a randomized clinical trial. Blood pressure, urinary albumin/creatinine ratio (UACR), serum creatinine, estimated glomerular filtration rate (eGFR) and serum K level were measured before randomization and after 24 weeks.. Ramipril and eplerenone monotherapy showed a significant lowering of UACR compared with baseline levels (p ≤ 0.0001). The eplerenone/ramipril combination group showed a more significant reduction of UACR compared with the ramipril and eplerenone monotherapy groups (p = 0.0001). There was a more significant lowering of systolic blood pressure in the combination group (p < 0.0001). A nonsignificant change of serum potassium level, serum creatinine and eGFR was found among the 3 groups.. Addition of eplerenone to ACEI shows an added antialbuminuric effect without significant change of the serum K level compared with eplerenone or ACEI.

Topics: Diabetes Mellitus, Type 2; Diabetic Nephropathies; Eplerenone; Humans; Prospective Studies; Ramipril; Single-Blind Method

Impaired coronary circulatory function predicts cardiovascular events, the leading cause of death in patients with diabetes mellitus. Aldosterone causes cardiovascular injury and is not suppressed by chronic angiotensin converting enzyme (ACE) inhibitor therapy.. Our objective was to assess whether mineralocorticoid receptor activation contributes to coronary circulatory dysfunction in patients with diabetes who are already receiving ACE inhibitor therapy.. A randomized, double-blind, crossover study with an intervening washout period of at least 4 wk was conducted with ambulatory patients from the community.. Patients included 16 subjects (11 men, eight Caucasians; mean age, 53 yr; mean body mass index, 38.0 kg/m2) with diabetes and albuminuria but without clinical cardiovascular disease.. ACE inhibitors were switched to enalapril 20 mg daily, and other antihypertensives were discontinued. Amlodipine 5-10 mg daily was added to achieve blood pressures less than 130/80 mm Hg. Subjects then received, in random order, 6 wk of the mineralocorticoid receptor antagonist eplerenone 50 mg (with placebo pill) daily and 6 wk of another diuretic, hydrochlorothiazide 12.5 mg (with potassium 10 mEq) daily.. Before and after each 6-wk treatment period, we measured coronary circulatory function (adenosine-stimulated myocardial perfusion reserve) and endothelial function (brachial artery reactivity and peripheral arterial tonometry).. The eplerenone and hydrochlorothiazide groups had similar blood pressures, serum potassium, glycemia, and endothelial function. Although pretreatment myocardial perfusion reserve did not differ between groups, myocardial perfusion reserve was significantly higher after eplerenone than after hydrochlorothiazide (median 1.57 vs. 1.30; P = 0.03).. Mineralocorticoid receptor blockade improves coronary circulatory function compared with hydrochlorothiazide in patients with diabetes already receiving ACE inhibitor therapy.

Topics: Adult; Albuminuria; Angiotensin-Converting Enzyme Inhibitors; Blood Glucose; Blood Pressure; Brachial Artery; Coronary Circulation; Cross-Over Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diuretics; Drug Therapy, Combination; Eplerenone; Female; Humans; Hydrochlorothiazide; Male; Middle Aged; Mineralocorticoid Receptor Antagonists; Pilot Projects; Potassium; Renal Circulation; Spironolactone

Mineralocorticoid receptor antagonist (MRA) when combined with either angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) may provide additional benefits of cardiovascular and kidney disease risk reduction in patients with diabetic kidney disease (DKD) and hypertension. We evaluated the effectiveness of combination therapy (MRAs, either spironolactone or eplerenone, plus ACEI/ARB) compared with monotherapy (ACEI/ARB only) in patients with DKD and hypertension.. Retrospective cohort study was performed in patients (age ≥ 18 years) with hypertension, diabetes, and albuminuria between 2008 and 2018 within an integrated health system. MRA with ACEI/ARB compared to ACEI/ARB alone was evaluated on composite of cardiovascular events, progression to end-stage kidney disease, or all-cause mortality. Hyperkalemia was compared as a safety outcome.. We identified 1282 patients who received MRAs with ACEI/ARBs and 5484 patients who received ACEI/ARBs alone. Median exposure time for combination therapy was 126 days. The rates per 100 person-years of cardiovascular, kidney, or all-cause mortality outcomes were 12.2 and 9.2 for combination therapy and monotherapy, respectively (hazard ratios = 1.24, 95% Confidence Interval (CI):0.94, 1.63). Patients receiving combination therapy had greater reduction in urine albumin-to-creatinine ratio compared with monotherapy (Mean reduction: 823 and 585 mg/g; p < 0.001, respectively). Hyperkalemia was more frequent in combination therapy versus monotherapy (22.3 vs. 10.9 per 100 person-years for combination and monotherapy, respectively; hazard ratios = 1.78, 95%CI: 1.42, 2.24).. Among patients with DKD and hypertension, the short-term use of MRAs, either spironolactone or eplerenone, in combination with ACEI/ARBs, was not associated with lower risk of cardiovascular or kidney outcomes compared with ACEI/ARB monotherapy. The risk of hyperkalemia and the short duration of combination therapy may suggest a real-world clinical challenge for MRA with ACEI/ARB combination therapy.

Topics: Adolescent; Adult; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Cardiovascular Diseases; Diabetic Nephropathies; Drug Therapy, Combination; Eplerenone; Humans; Hypertension; Kidney Diseases; Mineralocorticoid Receptor Antagonists; Retrospective Studies; Spironolactone; Treatment Outcome

Increased activation of the renin-angiotensin-aldosterone system (RAAS) and elevated growth factor production are of crucial importance in the development of renal fibrosis leading to diabetic kidney disease. The aim of this study was to provide evidence for the antifibrotic potential of RAAS inhibitor (RAASi) treatment and to explore the exact mechanism of this protective effect. We found that RAASi ameliorate diabetes-induced renal interstitial fibrosis and decrease profibrotic growth factor production. RAASi prevents fibrosis by acting directly on proximal tubular cells, and inhibits hyperglycaemia-induced growth factor production and thereby fibroblast activation. These results suggest a novel therapeutic indication and potential of RAASi in the treatment of renal fibrosis.. In diabetic kidney disease (DKD) increased activation of renin-angiotensin-aldosterone system (RAAS) contributes to renal fibrosis. Although RAAS inhibitors (RAASi) are the gold standard therapy in DKD, the mechanism of their antifibrotic effect is not yet clarified. Here we tested the antifibrotic and renoprotective action of RAASi in a rat model of streptozotocin-induced DKD. In vitro studies on proximal tubular cells and renal fibroblasts were also performed to further clarify the signal transduction pathways that are directly altered by hyperglycaemia. After 5 weeks of diabetes, male Wistar rats were treated for two more weeks per os with the RAASi ramipril, losartan, spironolactone or eplerenone. Proximal tubular cells were cultured in normal or high glucose (HG) medium and treated with RAASi. Platelet-derived growth factor (PDGF) or connective tissue growth factor (CTGF/CCN2)-induced renal fibroblasts were also treated with various RAASi. In diabetic rats, reduced renal function and interstitial fibrosis were ameliorated and elevated renal profibrotic factors (TGFβ1, PDGF, CTGF/CCN2, MMP2, TIMP1) and alpha-smooth muscle actin (αSMA) levels were decreased by RAASi. HG increased growth factor production of HK-2 cells, which in turn induced activation and αSMA production of fibroblasts. RAASi decreased tubular PDGF and CTGF expression and reduced production of extracellular matrix (ECM) components in fibroblasts. In proximal tubular cells, hyperglycaemia-induced growth factor production increased renal fibroblast transformation, contributing to the development of fibrosis. RAASi, even in non-antihypertensive doses, decreased the production of profibrotic factors and directly prevented fibroblast activation. All these findings suggest a novel therapeutic role for RAASi in the treatment of renal fibrosis.

Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Cell Line; Connective Tissue Growth Factor; Diabetes Mellitus, Experimental; Diabetic Nephropathies; Epithelial Cells; Eplerenone; Fibroblasts; Fibrosis; Humans; Kidney; Losartan; Male; Mannitol; Mineralocorticoid Receptor Antagonists; Proto-Oncogene Proteins c-sis; Ramipril; Rats, Wistar; Renin-Angiotensin System; Spironolactone

There is still insufficient data concerning the clinical effects of eplerenone, a selective aldosterone blocker, in patients with non-diabetic chronic kidney disease (CKD).. This study included non-diabetic CKD patients with urinary protein excretion (UPE) of 1.0 g/gCr or more in spite of long-term treatment with renin-angiotensin system (RAS) inhibitors. The clinical effects of eplerenone (25-50 mg/day) were investigated for 12 months.. Eplerenone treatment was associated with a 38% reduction in UPE after 12 months. There was only a slight increase in the serum potassium level. The reduction of proteinuria was observed more prominently in patients with modestly impaired renal function than in those with preserved renal function at baseline.. The long-term administration of low-dose eplerenone was effective and safe for the treatment of non-diabetic CKD patients who showed persistent proteinuria in spite of therapy with RAS inhibitors.

Topics: Adult; Aged; Blood Pressure; Diabetic Nephropathies; Eplerenone; Female; Glomerular Filtration Rate; Humans; Kidney Failure, Chronic; Male; Middle Aged; Mineralocorticoid Receptor Antagonists; Multivariate Analysis; Proteinuria; Spironolactone; Time Factors

Mineralocorticoid receptor (MR) blockade is an effective treatment for hypertension and diabetic nephropathy. There are no data on the effects of MR blockade on diabetic peripheral neuropathy (DPN). The aim of this study was to determine whether MRs are present in the peripheral nerves and to investigate the effectiveness of MR blockade on DPN in streptozotocin (STZ)-induced diabetic rats.. Expression of MR protein and messenger RNA (mRNA) was examined in the peripheral nerves using Western blot analysis and RT-PCR. We next studied the effects of the selective MR antagonist eplerenone and the angiotensin II receptor blocker candesartan on motor and sensory nerve conduction velocity (NCV), morphometric changes and cyclooxygenase-2 (COX-2) gene and NF-κB protein expression in the peripheral nerves of STZ-induced diabetic rats.. Expression of MR protein and mRNA in peripheral nerves was equal to that in the kidney. Motor NCV was significantly improved by 8 weeks of treatment with either eplerenone (39.1 ± 1.2 m/s) or candesartan (46.4 ± 6.8 m/s) compared with control diabetic rats (33.7 ± 2.0 m/s) (p < 0.05). Sensory NCV was also improved by treatment with candesartan or eplerenone in diabetic rats. Eplerenone and candesartan caused significant improvement in mean myelin fibre area and mean myelin area compared with control diabetic rats (p < 0.05). COX-2 mRNA and NF-κB protein were significantly elevated in the peripheral nerves of diabetic rats compared with control rats, and treatment with eplerenone or candesartan reduced these changes in gene expression (p < 0.05).. MR blockade may have neuroprotective effects on DPN.

Topics: Angiotensin II Type 1 Receptor Blockers; Animals; Benzimidazoles; Biphenyl Compounds; Blotting, Western; Diabetes Mellitus, Experimental; Diabetic Nephropathies; Eplerenone; Male; Mineralocorticoid Receptor Antagonists; NF-kappa B; Peripheral Nerves; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; Receptors, Mineralocorticoid; RNA, Messenger; Spironolactone; Tetrazoles

We studied the effect of the combined treatment with an angiotensin-converting enzyme (ACE) inhibitor (ramipril) and eplerenone compared with ramipril alone in streptozocin-induced diabetic rats.. Wistar rats were divided into 4 groups: nondiabetic controls, streptozocin-treated diabetic rats (50 mg/kg), diabetic rats receiving ramipril (1 mg/kg) and diabetic rats treated with the combination of ramipril (1 mg/kg) and eplerenone (100 mg/kg) for 8 weeks. Our model produced early-stage diabetic nephropathy.. The diabetic rats developed polyuria, proteinuria, hyperfiltration (assessed by creatinine clearance) and histopathological evidence of renal injury including glomerular hypertrophy and mesangial expansion. Ramipril reduced proteinuria but its combination with eplerenone did not produce any greater benefit. Both treatment approaches prevented glomerular hypertrophy. Addition of eplerenone to ramipril prevented glomerular hyperfiltration.. Whether eplerenone should be used in addition to an ACE inhibitor or an angiotensin receptor blocker at an early stage of diabetic nephropathy remains questionable.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Creatinine; Diabetes Mellitus, Experimental; Diabetic Nephropathies; Drug Therapy, Combination; Eplerenone; Glomerular Mesangium; Hypertrophy; Kidney Glomerulus; Male; Mineralocorticoid Receptor Antagonists; Proteinuria; Ramipril; Random Allocation; Rats; Rats, Wistar; Severity of Illness Index; Spironolactone

Recent data suggest that aldosterone antagonists have beneficial effects on diabetic nephropathy. In this study, we investigated the dose-dependent effect of eplerenone and a combined treatment with eplerenone and enalapril compared with each drug alone on renal function in type II diabetic rats. To further explore the molecular mechanism of action of combination therapy, we also performed in vitro study.. The animals were divided into six groups as follows: normal control Long-Evans Tokushima Otsuka (LETO) rats, Otsuka Long-Evans Tokushima Fatty (OLETF) rats, OLETF rats treated with low dose of eplerenone (50 mg/kg/day), OLETF rats treated with high dose of eplerenone (200 mg/kg/day), OLETF rats treated with enalapril (10 mg/kg/day) and OLETF rats treated with a combination of both drugs (eplerenone 200 mg/kg/day and enalapril 10 mg/kg/day) for 6 months.. Treatment of OLETF rats had no significant effect on body weight, kidney weight and blood glucose levels. However, urinary albumin excretion, glomerular filtration rate and glomerulosclerosis were significantly improved in the enalapril group and improvement was observed in a dose-dependent manner in the eplerenone groups; the most dramatic decreases were observed in the combination group. In accordance with these findings, renal expressions of TGF-beta1, type IV collagen and PAI-1 were also markedly decreased in the treatment groups, with the combined treatment providing the most significant level of improvement. In cultured mesangial cells, combined treatment resulted in an additive decrease in TGF-beta1, PAI-1 and collagen gene expressions and protein production induced by high glucose and aldosterone stimulation.. Aldosterone receptor antagonism provided additional benefits beyond blockade of the renin-angiotensin system in type II diabetic nephropathy.

Topics: Albuminuria; Angiotensin-Converting Enzyme Inhibitors; Animals; Base Sequence; Collagen Type IV; Diabetes Mellitus, Type 2; Diabetic Nephropathies; DNA Primers; Dose-Response Relationship, Drug; Drug Therapy, Combination; Enalapril; Eplerenone; Extracellular Matrix Proteins; Gene Expression; Glomerular Filtration Rate; In Vitro Techniques; Male; Mesangial Cells; Mineralocorticoid Receptor Antagonists; Plasminogen Activator Inhibitor 1; Rats; Rats, Inbred OLETF; Renin-Angiotensin System; Spironolactone; Transforming Growth Factor beta; Transforming Growth Factor beta1

To determine whether mineralocorticoid receptor (MR) activation plays a role in diabetic renal injury and whether this role differs in types 1 and 2 diabetes mellitus, we examined the effect of a MR antagonist on renal injury in rodent models of type 1 (streptozotocin-treated rat) and type 2 (db/db mouse) diabetes. We studied three groups of 8-wk-old, uninephrectomized Wistar rats for 4 wk: diabetic streptozotocin- (55 mg/kg) treated rats (n = 11), diabetic streptozotocin-treated rats receiving the MR antagonist eplerenone (n = 15), and nondiabetic rats (n = 9). In addition, we studied three groups of 8-wk-old mice for 16 wk: diabetic db/db mice (n = 10), diabetic db/db mice treated with eplerenone (n = 8), and nondiabetic, db/+ littermates (n = 11). Diabetic rats and mice developed albuminuria and histopathological evidence of renal injury, including glomerular hypertrophy, mesangial expansion, and tubulointerstitial injury as well as increased renal cortical levels of MR protein, MR mRNA, TGFbeta mRNA, and osteopontin mRNA. All of these changes were significantly reduced by treatment with eplerenone except for the elevated MR levels. The beneficial effects of eplerenone were not attributable to changes in blood pressure or glycemia. In summary, MR expression was increased in kidneys of diabetic rodents, and MR antagonists effectively reduced diabetic renal injury irrespective of the species or specific cause of the diabetes. Thus, these data suggest that MR activation is a critical factor in the early pathogenesis of renal disease in both type 1 and type 2 diabetes mellitus.

Topics: Albuminuria; Animals; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Eplerenone; Hypertrophy; Kidney; Male; Mice; Mice, Inbred C57BL; Mineralocorticoid Receptor Antagonists; Osteopontin; Rats; Rats, Wistar; Receptors, Mineralocorticoid; RNA, Messenger; Spironolactone; Streptozocin; Systole