Aging increases Oxidative Stress and Renal Expression of Oxidant and Antioxidant Enzymes that Are Associated with an Increased Trend in Systolic Blood Pressure. Issue 3 (2009)

• Record Type: Journal Article
• Authors: Gomes, Pedro; Simão, Sónia; Silva, Elisabete; Pinto, Vanda; Amaral, João S.; Afonso, Joana; Serrão, Maria Paula; Pinho, Maria João; Soares-da-Silva, Patrício
• Is Part Of: Oxidative medicine and cellular longevity. Volume 2:Issue 3(2009)
• Page Start: 138
• Page End: 145
• Publication Date: 2009
• Subjects: aging -- oxidative stress -- kidney -- hydrogen peroxide -- NADPH oxidase -- antioxidant enzymes -- Wistar Kyoto rat; Oxidative stress -- Periodicals; Cells -- Aging -- Periodicals; Cells -- Aging; Oxidative stress; Oxidative Stress -- Periodicals; Cell Aging -- Periodicals; Periodicals; 611.0181
• DOI: 10.4161/oxim.2.3.8819
• Languages: English
• ISSNs: 1942-0900

Abstract

Abstract : The aim of this study was to investigate whether the effects of aging on oxidative stress markers and expression of major oxidant and antioxidant enzymes associate with impairment of renal function and increases in blood pressure. To explore this, we determined age-associated changes in lipid peroxidation (urinary malondialdehyde), plasma and urinary hydrogen peroxide (H2 O2 ) levels, as well as renal H2 O2 production, and the expression of oxidant and antioxidant enzymes in young (13 weeks) and old (52 weeks) male Wistar Kyoto (WKY) rats. Urinary lipid peroxidation levels and H2 O2 production by the renal cortex and medulla of old rats were higher than their young counterparts. This was accompanied by overexpression of NADPH oxidase components Nox4 and p22 phox in the renal cortex of old rats. Similarly, expression of superoxide dismutase (SOD) isoforms 2 and 3 and catalase were increased in the renal cortex from old rats. Renal function parameters (creatinine clearance and fractional excretion of sodium), diastolic blood pressure and heart rate were not affected by aging, although slight increases in systolic blood pressure were observed during this 52-week period. It is concluded that overexpression of renal Nox4 and p22 phox and the increases in renal H2 O2 levels in aged WKY does not associate with renal functional impairment or marked increases in blood pressure. It is hypothesized that lack of oxidative stress-associated effects in aged WKY rats may result from increases in antioxidant defenses that counteract the damaging effects of H2 O2 .