(–)-Epicatechin administration protects kidney against modifications induced by short-term L-NAME treatment in rats
(–)-Epicatechin, a flavonoid omnipresent in plants being part of the human diet, has been associated to beneficial effects on cardiovascular health. The aim of this work was to evaluate the protective effect of (–)-epicatechin of NO deprivated animals on kidney, and the possible mechanism of action. To address the effects of the inhibition of NO synthases (NOSs) by their inhibitor N(ω)-nitro-L-arginine methyl ester (L-NAME) administration in the absence of the long-term effects of NO deprivation, the extent of the treatments was restricted to 4 days: male Sprague Dawley rats were divided into three groups: control (C), receiving water and a standard diet; L-NAME (L), receiving a solution of L-NAME (360 mg/l) as beverage and the standard diet; and L-NAME-(–)-epicatechin (LE), receiving L-NAME solution as beverage and standard diet added with (–)-epicatechin (4g/kg diet). L group showed altered kidney function parameters, evaluated as plasma urea and creatinine. Parallely, kidney oxidative stress markers, as superoxide anion production, malondyaldehide content, and 3-nitrotyrosine-protein adducts were significantly increased in NO deprivated animals. L-NAME treatment induced modifications in kidney NO availability determinants: increased expression of NOXs subunits (p47phox, gp91phox, NOXO1, NOX4), and lowered NOS activity. (–)-Epicatechin administration was associated to kidney function parameters similar to control values, and the normalization in oxidative stress markers, the expression of p47phox, gp91phox, and NOX4, and NOS activity. These results suggest that (–)-epicatechin can mitigate NO-mediated impairment of kidney function, in part due to its capacity to modulate NOXs, NOSs, and consequently oxidative stress, and NO bioavailability.