Protective Role of Apelin Against Cyclosporine-Induced Renal Tubular Injury in Rats

• Published in: Transplantation proceedings Vol. 49; no. 6; pp. 1499 - 1509
• Main Authors: Kim, J.S., Yang, J.W., Han, B.G., Kwon, H.J., Kim, J.H., Choi, S.O.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2017
• Subjects: Acute Kidney Injury - chemically induced; Acute Kidney Injury - urine; Animals; Apelin - physiology; Creatinine - urine; Cyclosporine - administration & dosage; Cyclosporine - adverse effects; Glomerular Filtration Rate - drug effects; Immunosuppressive Agents - adverse effects; Kidney Function Tests; Kidney Tubules - injuries; Lipocalin-2 - urine; Male; Nitric Oxide Synthase Type III - metabolism; Rats
• ISSN: 0041-1345; 1873-2623
• DOI: 10.1016/j.transproceed.2017.03.080

Cyclosporine (CsA) usually reduces glomerular filtration rate (GFR) but also can induce tubular injury without resulting in GFR reduction. Apelin is an endogenous ligand for the apelin receptor and has diverse physiologic roles related to hemodynamic or metabolic processes. We investigated the renoprotective role of apelin against CsA-induced tubular toxicity in rats. Rats were given CsA (15 mg/kg/day) and/or apelin-13 (15 μg/kg/day) for 7 days via subcutaneous injection. We performed serum and urinary assays of creatinine and neutrophil gelatinase-associated lipocalin (NGAL) to estimate renal injury and performed Western blotting for endothelial nitric oxide synthase and nuclear factor of activated T-cell cytoplasmic 1 (NFATc1) to document the underlying mechanism. The CsA-treated group showed increased urinary creatinine excretion, polyuria, and renal glycosuria without GFR reduction, suggesting adequate CsA-induced renal tubular injury. Urinary NGAL excretion also increased significantly in the CsA group. Conversely, apelin attenuated CsA-induced tubular injury and had no effect on urinary NGAL excretion. In histopathologic examination, the apelin-treated group had lower tubulo-interstitial injury scores compared with those in the CsA group. Regarding the effects of apelin, our results indicate that apelin provides protection against CsA-induced tubular injury by activating nitric oxide and/or the NFATc1 pathway. Notably, we also found that CsA inhibits renal glucose reabsorption by reducing Na+-K+ ATPase expression and that apelin reverses reduced renal glucose reabsorption by CsA in tubular cells. Our study demonstrates the renoprotective effect of apelin against CsA-induced renal tubular toxicity and provides novel insights into the effects of CsA and apelin on renal tubular cells. •Apelin can prevent cyclosporine-induced renal tubular injury.•The mechanism relies on the activation of nitric oxide and NFATc1 pathways.•Cyclosporine induced renal glycosuria via decrease in Na+-K+ ATPase expression.•Apelin could modulate transmembrane molecules concerning renal glucose reabsorption.