Disciplina de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil.
PLoS One. 2012;7(8):e44004. doi: 10.1371/journal.pone.0044004. Epub 2012 Aug 31.
Malaria associated-acute kidney injury (AKI) is associated with 45% of mortality in adult patients hospitalized with severe form of the disease. However, the causes that lead to a framework of malaria-associated AKI are still poorly characterized. Some clinical studies speculate that oxidative stress products, a characteristic of Plasmodium infection, as well as proinflammatory response induced by the parasite are involved in its pathophysiology. Therefore, we aimed to investigate the development of malaria-associated AKI during infection by P. berghei ANKA, with special attention to the role played by the inflammatory response and the involvement of oxidative stress. For that, we took advantage of an experimental model of severe malaria that showed significant changes in the renal pathophysiology to investigate the role of malaria infection in the renal microvascular permeability and tissue injury. Therefore, BALB/c mice were infected with P. berghei ANKA. To assess renal function, creatinine, blood urea nitrogen, and ratio of proteinuria and creatininuria were evaluated. The products of oxidative stress, as well as cytokine profile were quantified in plasma and renal tissue. The change of renal microvascular permeability, tissue hypoxia and cellular apoptosis were also evaluated. Parasite infection resulted in renal dysfunction. Furthermore, we observed increased expression of adhesion molecule, proinflammatory cytokines and products of oxidative stress, associated with a decrease mRNA expression of HO-1 in kidney tissue of infected mice. The measurement of lipoprotein oxidizability also showed a significant increase in plasma of infected animals. Together, our findings support the idea that products of oxidative stress, as well as the immune response against the parasite are crucial to changes in kidney architecture and microvascular endothelial permeability of BALB/c mice infected with P. berghei ANKA.
疟疾相关急性肾损伤(AKI)与成人严重疟疾患者 45%的死亡率相关。然而,导致疟疾相关 AKI 的原因仍未得到充分描述。一些临床研究推测,氧化应激产物(疟原虫感染的特征)以及寄生虫引起的促炎反应参与了其病理生理学过程。因此,我们旨在研究伯氏疟原虫 ANKA 感染导致疟疾相关 AKI 的发展,特别关注炎症反应和氧化应激的作用。为此,我们利用严重疟疾的实验模型,该模型显示肾脏病理生理学发生了显著变化,以研究疟疾感染在肾脏微血管通透性和组织损伤中的作用。因此,BALB/c 小鼠被感染伯氏疟原虫 ANKA。为了评估肾功能,评估了肌酐、血尿素氮以及蛋白尿与肌酐比值。在血浆和肾组织中定量了氧化应激产物以及细胞因子谱。还评估了肾脏微血管通透性的变化、组织缺氧和细胞凋亡。寄生虫感染导致肾功能障碍。此外,我们观察到感染小鼠肾脏组织中粘附分子、促炎细胞因子和氧化应激产物的表达增加,同时 HO-1 的 mRNA 表达减少。脂蛋白氧化能力的测量也显示感染动物的血浆中显著增加。总之,我们的研究结果支持这样一种观点,即氧化应激产物以及针对寄生虫的免疫反应对于感染伯氏疟原虫 ANKA 的 BALB/c 小鼠的肾脏结构和微血管内皮通透性的变化至关重要。