The present study was designed to investigate the nephroprotective effect of bromelain against oxidative stress stimulated by aluminium chloride in rats. Rats were grouped as follows; group one was used as control while groups 2, 3 and 4 were treated orally with bromelain (250 mg/kg, daily), aluminium chloride (AlCl₃; 34 mg/kg BW, every other day) and bromelain plus AlCl₃ for 30 days, respectively. Administration of AlCl₃ caused a significant reduction in rats’ body and kidney weights, and increased Al accumulation in kidney tissue. Also, AlCl₃ treatment elevated thiobarbituric acid reactive substances, hydrogen peroxide, kidney functions biomarkers levels and lactate dehydrogenase activity. While enzymatic (SOD, CAT, GPx, GR, GST) and non-enzymatic (GSH) antioxidants, protein content, and alkaline phosphatase activity were significantly decreased. In addition, significant alterations in lipid and protein profiles were detected. Furthermore, histopathological and immunohistochemical variations were seen in kidney sections supporting the obtained biochemical changes. Otherwise, rats supplemented with bromelain singly declined lipid peroxidation and improved most of the studied parameters. Moreover, rats pretreated with bromelain followed by AlCl₃ intoxication showed significant alleviation in lipid peroxidation, antioxidant status and biochemical indices with respect to AlCl₃ treated group. Conclusively, bromelain has beneficial protective effects and has the capability to counteract the toxic influence of AlCl₃. So, bromelain might represent a novel approach in the therapy of metal toxicity because of its antioxidant and chelating properties.

本研究旨在研究菠萝蛋白酶对大鼠氯化铝刺激的氧化应激的肾脏保护作用。将大鼠分组如下。第一组用作对照组，而第2、3和4组分别口服菠萝蛋白酶（250 mg / kg，每天），氯化铝（AlCl ₃； 34 mg / kg BW，隔日一次）和菠萝蛋白酶加AlCl ₃口服30天分别。施用AlCl ₃导致大鼠体重和肾脏重量显着减少，并增加了肾脏在肾脏组织中的积累。另外，AlCl ₃治疗升高的硫代巴比妥酸反应性物质，过氧化氢，肾功能生物标志物水平和乳酸脱氢酶活性。酶（SOD，CAT，GPx，GR，GST）和非酶（GSH）抗氧化剂的蛋白质含量和碱性磷酸酶活性均明显降低。另外，检测到脂质和蛋白质谱的显着改变。此外，在支持所获得的生化变化的肾脏切片中观察到组织病理学和免疫组织化学变化。否则，补充菠萝蛋白酶的大鼠会单独降低脂质过氧化作用并改善大多数研究参数。此外，用菠萝蛋白酶和AlCl ₃预处理的大鼠与AlCl ₃处理组相比，中毒显示出脂质过氧化，抗氧化状态和生化指标的显着减轻。总之，菠萝蛋白酶具有有益的保护作用，并具有抵消AlCl ₃毒性作用的能力。因此，菠萝蛋白酶由于其抗氧化剂和螯合性能，可能代表金属毒性治疗的一种新方法。