Pimentel V C, Bellé L P, Pinheiro F V, De Bona K S, Da Luz S C A, Moretto M B
Postgraduate Program in Pharmaceutical Sciences, Health Science Centre, Santa Maria, RS, Brazil.
Int J Dev Neurosci. 2009 Dec;27(8):857-62. doi: 10.1016/j.ijdevneu.2009.06.003. Epub 2009 Jun 25.
Hypoxia ischemia (HI) is a common cause of damage in the fetal and neonatal brain. Lifelong disabilities such as cerebral palsy, epilepsy, behavioral and learning disorders are some of the consequences of brain injury acquired in the perinatal periods. Inflammation and formation of free radicals appear to play key roles in neonatal HI. The aim of this study was to describe the chronological sequence of adenosine deaminase (ADA) activity, the oxidative damage changes and astrocyte response using the classic model of neonatal HI. We observed an increase in the activity of ADA and lipid peroxidation in the cerebral cortex 8 days after neonatal HI. This was accompanied by a GFAP-positive, and the degree of brain damage was determined histochemically by hematoxylin-eosin (HE). Taking into account the important anti-inflammatory role of adenosine, ADA may provide an efficient means for scavenging cell-surrounding adenosine and play an important part in subsequent events of neonatal HI in association with GFAP reactive gliosis. The present investigation showed that neonatal HI causes the increase of free radicals and significant damage in the cerebral cortex. The increase in ADA activity may reflect the activation of the immune system caused by HI because the morphological analysis exhibited a lymphocytic infiltration.
缺氧缺血(HI)是胎儿和新生儿脑损伤的常见原因。脑瘫、癫痫、行为和学习障碍等终身残疾是围产期脑损伤的一些后果。炎症和自由基的形成似乎在新生儿HI中起关键作用。本研究的目的是使用新生儿HI的经典模型描述腺苷脱氨酶(ADA)活性、氧化损伤变化和星形胶质细胞反应的时间顺序。我们观察到新生儿HI后8天,大脑皮质中ADA活性和脂质过氧化增加。这伴随着GFAP阳性,并且通过苏木精-伊红(HE)组织化学法确定脑损伤程度。考虑到腺苷重要的抗炎作用,ADA可能提供一种清除细胞周围腺苷的有效手段,并在与GFAP反应性胶质增生相关的新生儿HI后续事件中发挥重要作用。本研究表明,新生儿HI会导致大脑皮质中自由基增加和显著损伤。ADA活性的增加可能反映了HI引起的免疫系统激活,因为形态学分析显示有淋巴细胞浸润。