Balkan endemic nephropathy (BEN) represents a chronic tubulointerstitial nephropathy which is followed by the progression of kidney fibrosis to end-stage kidney failure. The critical involvement of poisons in food (aristolochic acid (AA), ochratoxin, and heavy metals) and selenium deficiency are among nutritive factors which contribute to the pathogenesis of BEN, due to reactive oxygen species (ROS) liberation and/or decreased antioxidative defence system. The aim of the study is to distinguish a possible systemic and local origin of ROS through the measurement of xanthine oxidase (XO) activity in urine and plasma, along with the determination of the oxidative changes in lipids and proteins. The study included 50 patients with BEN and 38 control healthy subjects. We noted increased levels of both thiobarbituric acid-reactive substances (TBARS) and advanced oxidation protein products (AOPPs) in the plasma of patients with BEN, compared to the control group (). The urinary levels of AOPPs were higher in patients with BEN in comparison to the control (). The specific activity of XO was significantly lower in plasma and urine in BEN samples, compared to controls (). Based on these results, we hypothesize that XO might not be considered a direct systemic or local contributor to ROS production in BEN, most probably because of the diminished kidney functional tissue mass and/or AA-induced changes in purine nucleotide conformation. The increased AOPP and TBARS level in both plasma and urine in BEN may predict ROS systemic liberation with toxic local effects.

中文翻译：

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巴尔干地方性肾病的局部和全身氧化应激与黄嘌呤氧化酶活性无关。


巴尔干地方性肾病（BEN）代表一种慢性肾小管间质性肾病，随后肾纤维化进展至终末期肾衰竭。由于活性氧 (ROS) 释放和/或抗氧化防御能力下降，食物中的毒物（马兜铃酸 (AA)、赭曲霉毒素和重金属）和硒缺乏是导致 BEN 发病的营养因素之一系统。该研究的目的是通过测量尿液和血浆中的黄嘌呤氧化酶（XO）活性以及测定脂质和蛋白质的氧化变化来区分ROS可能的全身和局部来源。该研究包括 50 名 BEN 患者和 38 名健康对照受试者。我们注意到，与对照组相比，BEN 患者血浆中硫代巴比妥酸反应物质 (TBARS) 和高级氧化蛋白产物 (AOPP) 的水平有所增加。 ）。与对照组相比，BEN 患者尿中 AOPP 水平较高（ ）。与对照相比，BEN 样品中血浆和尿液中 XO 的比活性显着降低（ ）。基于这些结果，我们假设 XO 可能不被认为是 BEN 中 ROS 产生的直接全身或局部贡献者，最有可能是因为肾功能组织质量减少和/或 AA 诱导的嘌呤核苷酸构象变化。 BEN 中血浆和尿液中 AOPP 和 TBARS 水平升高可能预示着 ROS 的全身释放，并具有局部毒性作用。