Nox1-derived oxidative stress as a common pathogenic link between obesity and hyperoxaluria-related kidney injury

AbstractSpecific relationships among reactive oxygen species, activation pathways, and inflammatory mechanisms involved in kidney injury were assessed in a combined model of obesity and hyperoxaluria. Male Wistar rats were divided into four groups: Control, HFD (high fat diet), OX (0.75% ethylene glycol), and HFD  + OX (combined model) Changes in basal O2− levels were evaluated by chemiluminescence in renal interlobar arteries and renal cortex. Furthermore, the effect of different inhibitors on NADPH-stimulated O2− generation was assessed in renal cortex. Oxidative stress sources, and local inflammatory mediators, were also determined, in parallel, by RT-PCR, and correlated with measures of renal function, urinary biochemistry, and renal structure. Rats from the HFD group developed overweight without lipid profile alteration. Tubular deposits of crystals were seen in OX and severely enhanced in HFD  + OX groups along with a significantly higher impairment of renal function. Basal oxidative stress was increased in renal cortex of OX rats and in renal arteries of HFD rats, while animals from the combined HFD + OX group exhibited the highest levels of oxidative stress in renal cortex, der ived from xanthine oxidase and COX-2. NADPH oxidase-dependent O2− generation was elevated in renal cortex of the OX group and markedly enhanced in the HFD  + OX rats, and associated to an up-regulation of Nox1 and a down-regulation of Nox4 expression. High levels of oxidat...
Source: Urolithiasis - Category: Urology & Nephrology Source Type: research