血红素加氧酶在阿尔茨海默病中的表达及意义

目的：研究血红素加氧酶（HO-1）在阿尔茨海默病（AD）额叶和海马中的表达,探讨其神经保护作用及机制.方法：选取诊断明确的AD尸检脑标本14例（AD组）;另选取中枢神经系统以外疾病、无显著脑病理改变的死亡病例32例为对照组.采用免疫组织化学染色法,以阳性表达程度和积分吸光度（IA）值观察HO-1在AD及对照组额叶和海马中的表达;采用免疫荧光双重染色方法,观察AD脑中HO-1与GFAP、Tau的共同表达.结果：AD组额叶与海马HO-1阳性率较对照组增高,且差异有统计学意义（ P〈0.05）;对照组不同年龄段HO-1阳性率随年龄增高,青年组与高龄组比阳性率差异有统计学意义（P〈0.05）;AD组IA值较对照组增高（ P〈0.05）,AD组海马IA值较额叶增高且差异有统计学意义（ P〈0.05）;部分神经元胞质内HO-1与Tau共同表达,星形胶质细胞内HO-1与GFAT共同表达.结论：HO-1可能通过启动内源性神经保护机制在AD中起脑保护作用.

Expression of Hemeoxygenase-1 in Brain of Alzheimer's Disease

Aim： To explore the expression and neuroprotective mechenism of hemeoxygenase- 1 in brain of Alzheimer＇ s disease（AD）. Methods： 32 brains of subjects who died without clinical or pathological involvement of central nervous system and 14 brains of AD patients were obtained at autopsy. Frontal lobe and hippocampus were mainly investigated. Immunostaining was carried out to observe the expression of HO-1. Positive expression degree and IA Value were observed. Double immunoflurescence staining was used to analyze coexpression of HO- 1/GFAP and HO-1/Tau. Results： The positive expression rate of HO-1 differed significantly between AD and control group（P〈0.05） and increased with age in control group, with statistically significant difference between aged and elderly aged control groups（P〈0.05）. IA value of HO-1 was significantly increased in AD cases compared with controls（P〈0.05）. There was significant IA difference of HO-1 between hippocampus and frontal lobe（P〈0.05）. There were coexpression of HO-1/Tau in neurons and HO-1/GFAP in glial cells. Conclusion： HO-1 may play a role of neuroprotection via some endogenous mechenism in the progression of AD.