Mira Pavkovic

INTRODUCTION: The nonsteroidal mineralocorticoid receptor (MR) antagonist finerenone and sodium-glucose cotransporter-2 (SGLT2) inhibitors have demonstrated clinical benefits in CKD patients with type 2 diabetes. Clinical data analyzing the potential value of a combination therapy are currently limited. We therefore investigated cardiorenal protection of respective mono- and combination therapy in a preclinical model of hypertension-induced end-organ damage. METHODS: Cardiovascular (CV) morbidity and mortality were studied in hypertensive, N(ω)-nitro-L-arginine methyl ester-treated, renin-transgenic (mRen2)27 rats. Rats (10- to 11-week-old females, n = 13-17/group) were treated once daily orally for up to 7 weeks with placebo, finerenone (1 and 3 mg/kg), empagliflozin (3 and 10 mg/kg), or a combination of the respective low doses. Key outcome parameters included mortality, proteinuria, plasma creatinine and uric acid, blood pressure, and cardiac and renal histology. RESULTS: Placebo-treated rats demonstrated a 50% survival rate over the course of 7 weeks. Drug treatment resulted in variable degrees of survival benefit, most prominently in the low-dose combination group with a survival benefit of 93%. Monotherapies of finerenone or empagliflozin dose-dependently reduced proteinuria, while low-dose combination revealed an early, sustained, and over-additive reduction in proteinuria. Empagliflozin induced a strong and dose-dependent increase in urinary glucose excretion which was not influenced by finerenone coadministration in the combination arm. Low-dose combination but not respective low-dose monotherapies significantly reduced plasma creatinine and plasma uric acid after 6 weeks. Treatment with finerenone and the low-dose combination significantly decreased systolic blood pressure after 5 weeks. There was a dose-dependent protection from cardiac and kidney fibrosis and vasculopathy with both agents, while low-dose combination therapy was more efficient than the respective monotherapy dosages on most cardiorenal histology parameters. DISCUSSION/CONCLUSIONS: Nonsteroidal MR antagonism by finerenone and SGLT2 inhibition by empagliflozin confer CV protection in preclinical hypertension-induced cardiorenal disease. Combination of these 2 independent modes of action at low dosages revealed efficacious reduction in important functional parameters such as proteinuria and blood pressure, plasma markers including creatinine and uric acid, cardiac and renal lesions as determined by histopathology, and mortality indicating a strong potential for combined clinical use in cardiorenal patient populations.

Abstract BACKGROUND The prevalence of chronic kidney disease (CKD) is increasing, leading to significant morbidity and mortality. Kidney biopsy remains the gold standard for diagnosing the underlying etiology of CKD, but the procedure carries complication risks. The aim of this study was to identify novel noninvasive biomarkers correlating with kidney function and histopathology in biopsy-proven CKD patients. METHODS We profiled 2402 urinary microRNAs (miRNAs) to identify and confirm differentially expressed miRNAs associated with kidney function and histopathology in patients with diabetic nephropathy (n = 58) or lupus nephritis (n = 89), important etiologies of CKD, compared with healthy controls (n = 93 and 119, respectively). Top performing miRNAs were then measured in 2 independent multi-institutional cohorts of patients with diabetes mellitus with (n = 74) or without nephropathy (n = 71) and systemic lupus erythematosus with (n = 86) or without (n = 37) nephritis. RESULTS In patients with diabetic nephropathy, miR-2861, miR-1915-3p, and miR-4532 were down-regulated (>10-fold, P < 0.0001) and were associated with estimated glomerular filtration rate (P < 0.01) and interstitial fibrosis/tubular atrophy (P < 0.05). The c-statistics for miR-2861, miR-1915-3p, and miR-4532 were 0.91, 0.86, and 0.85, respectively. In lupus nephritis patients, miR-3201 and miR-1273e were down-regulated (>3-fold, P < 0.0001) and associated with endocapillary glomerular inflammation (P < 0.01), with c-statistics of 0.97 and 0.91, respectively. CONCLUSIONS We have identified novel miRNAs that correlate with histopathological lesions and functional markers of kidney damage to facilitate sensitive, specific, and noninvasive detection of diabetic nephropathy and lupus nephritis.

Drug-induced acute kidney injury (AKI) is often encountered in hospitalized patients. Although serum creatinine (SCr) is still routinely used for assessing AKI, it is known to be insensitive and nonspecific. Therefore, our objective was to evaluate kidney injury molecule 1 (KIM-1) in conjunction with microRNA (miR)-21, -200c, and -423 as urinary biomarkers for drug-induced AKI in humans. In a cross-sectional cohort of patients (n = 135) with acetaminophen (APAP) overdose, all 4 biomarkers were significantly (P < .004) higher not only in APAP-overdosed (OD) patients with AKI (based on SCr increase) but also in APAP-OD patients without clinical diagnosis of AKI compared with healthy volunteers. In a longitudinal cohort of patients with malignant mesothelioma receiving intraoperative cisplatin (Cp) therapy (n = 108) the 4 biomarkers increased significantly (P < .0014) over time after Cp administration, but could not be used to distinguish patients with or without AKI. Evidence for human proximal tubular epithelial cells (HPTECs) being the source of miRNAs in urine was obtained first, by in situ hybridization based confirmation of increase in miR-21 expression in the kidney sections of AKI patients and second, by increased levels of miR-21, -200c, and -423 in the medium of cultured HPTECs treated with Cp and 4-aminophenol (APAP degradation product). Target prediction analysis revealed 1102 mRNA targets of miR-21, -200c, and -423 that are associated with pathways perturbed in diverse pathological kidney conditions. In summary, we report noninvasive detection of AKI in humans by combining the sensitivity of KIM-1 along with mechanistic potentials of miR-21, -200c, and -423.