Fosinopril and losartan regulate klotho gene and nicotinamide adenine dinucleotide phosphate oxidase expression in kidneys of spontaneously hypertensive rats.

BACKGROUND/AIMS Klotho, a newly identified antiaging gene, predominantly detected in the kidney, has pleiotropic protective effects on kidney diseases. Several studies have confirmed the association between Klotho and oxidative stress. The present studies were performed to explore effects of fosinopril (Fos) and losartan (Los) on Klotho and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression in kidneys of spontaneously hypertensive rats (SHR). METHODS Twenty-four male 22-week-old SHR were randomly divided into three groups: model group, Fos group and Los group. Wistar-Kyoto rats were taken as control. After 8 weeks, urinary N-acetyl-β-D-glucosaminidase (NAGase), 24 h urinary protein (Upro), serum creatinine (Scr), blood urea nitrogen (BUN) and renal pathological changes were detected. Renal mRNA and protein expression of Klotho and three subunits of NADPH oxidase protein expression were evaluated. RESULTS As compared to the model group, NAGase, Upro, Scr and BUN were decreased; the typical renal pathological damage was relieved in the Fos or Los group. Fos or Los inhibited the reduction of Klotho expression, and reduced the elevation of NADPH oxidase expression. CONCLUSION Abnormal expression of Klotho and NADPH oxidase plays important roles in progression of hypertensive renal damage. Fos and Los can increase Klotho expression, and inhibit NADPH oxidase expression, which may be one of the mechanisms of their protective effects in hypertensive renal damage.