Cordeiro J L, Neves J D, Nicola F, Vizuete A F, Sanches E F, Gonçalves C A, Netto C A
Department of Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600, Porto Alegre, RS, 90035-003, Brazil.
Post-Graduation Program of Neurosciences, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, 90035-190, Brazil.
Cell Mol Neurobiol. 2022 Apr;42(3):739-751. doi: 10.1007/s10571-020-00964-6. Epub 2020 Sep 11.
Intracerebral hemorrhage (ICH) is a severe stroke subtype caused by the rupture of blood vessels within the brain. Increased levels of S100B protein may contribute to neuroinflammation after ICH through activation of astrocytes and resident microglia, with the consequent production of proinflammatory cytokines and reactive oxygen species (ROS). Inhibition of astrocytic synthesis of S100B by arundic acid (AA) has shown beneficial effects in experimental central nervous system disorders. In present study, we administered AA in a collagenase-induced ICH rodent model in order to evaluate its effects on neurological deficits, S100B levels, astrocytic activation, inflammatory, and oxidative parameters. Rats underwent stereotactic surgery for injection of collagenase in the left striatum and AA (2 μg/μl; weight × 0.005) or vehicle in the left lateral ventricle. Neurological deficits were evaluated by the Ladder rung walking and Grip strength tests. Striatal S100B, astrogliosis, and microglial activation were assessed by immunofluorescence analysis. Striatal levels of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) were measured by ELISA, and the ROS production was analyzed by dichlorofluorescein (DCF) oxidation. AA treatment prevented motor dysfunction, reduced S100B levels, astrogliosis, and microglial activation in the damaged striatum, thus decreasing the release of proinflammatory cytokines IL-1β and TNF-α, as well as ROS production. Taken together, present results suggest that AA could be a pharmacological tool to prevent the harmful effects of increased S100B, attenuating neuroinflammation and secondary brain damage after ICH.
脑出血(ICH)是一种由脑内血管破裂引起的严重中风亚型。S100B蛋白水平升高可能通过激活星形胶质细胞和常驻小胶质细胞,导致脑出血后神经炎症,进而产生促炎细胞因子和活性氧(ROS)。阿仑酸(AA)抑制星形胶质细胞合成S100B已在实验性中枢神经系统疾病中显示出有益作用。在本研究中,我们在胶原酶诱导的脑出血啮齿动物模型中给予AA,以评估其对神经功能缺损、S100B水平、星形胶质细胞活化、炎症和氧化参数的影响。大鼠接受立体定向手术,在左侧纹状体注射胶原酶,并在左侧侧脑室注射AA(2μg/μl;体重×0.005)或溶剂。通过阶梯行走和握力测试评估神经功能缺损。通过免疫荧光分析评估纹状体S100B、星形胶质细胞增生和小胶质细胞活化。通过酶联免疫吸附测定(ELISA)测量纹状体白细胞介素1β(IL-1β)和肿瘤坏死因子α(TNF-α)水平,并通过二氯荧光素(DCF)氧化分析ROS产生。AA治疗可预防运动功能障碍,降低受损纹状体中的S100B水平、星形胶质细胞增生和小胶质细胞活化,从而减少促炎细胞因子IL-1β和TNF-α的释放以及ROS产生。综上所述,目前的结果表明,AA可能是一种药理学工具,可预防S100B升高的有害影响,减轻脑出血后的神经炎症和继发性脑损伤。