老年与青壮年脑挫裂伤组织NGF的表达差异及意义

Expression difference and its significance of NGF in the contusive or lacerated brain tissue in the aged and young patients

目的研究衰老对脑挫裂伤组织神经生长因子(NGF)基因表达的影响,进一步探讨老年颅脑损伤病人神经功能缺失程度较重的分子生物学机制。方法收集重型颅脑损伤开颅手术中的脑挫裂伤组织,应用免疫组化和医学数码图像分析技术,观察老年组(≥60岁)和青壮年组(19～59岁)病人脑损伤后3～9h脑挫裂伤组织NGF蛋白的表达差异。结果脑损伤后NGF在老年和青壮年脑挫裂伤组织中的表达均明显增强;老年组脑挫裂伤组织中的NGF蛋白表达显著性低于青壮年组(P<0.05)。结论老年人脑挫裂伤后NGF表达水平下降明显,提示其受损神经元的修复和生存能力降低,这可能是老年颅脑损伤病人恢复不良的重要原因之一。

Objective To study the effect of aging on the expression of nerve growth factor （NGF） protein in the contusive or lacerated brain tissue after traumatic brain injury （TBI）, and furthering explore the molecular biological mechanism for old patients having more severe neurological deficits. Methods The contusive and lacerated brain tissues 3 to 9 hours after TBI were collected, and the expressions of NGF protein of the aged group （≥ 60 years old） and young group （19 to 59 years old） were analyzed by immunohistochemistry and digital image analysis system, to determine the possible susceptibility differences in the expression of NGF protein between the two groups. Results In the contusive and lacerated brain tissue, the expression of NGF protein was increased after TBI. However, the level of NGF protein in the contusive and lacerated brain tissue was statistically lower in the aged group than in the young group （P〈0.05）. Conclusion The expression of NGF after TBI is influenced by age. The lower level expression of NGF in aged patients suggests that the recovery and survival ability of aged neurons is lowered, which might be an important reason for the bad recovery of the aged patients after craniocerebral injury.