LAMP2A和MEF2D在增龄过程中大鼠髓核组织的表达及其意义  

Expression and significance of LAMP2A and MEF2D in nucleus pulpous of rats during the aging process

作　　者：叶伟[1] 梁安靖[1] 彭焰[1] 朱伟荣[1] 陈晋宸[1] 李春海[1] 黄东生[1] 

机构地区：[1]中山大学孙逸仙纪念医院脊柱外科,广州510120

出　　处：《中华实验外科杂志》2010年第11期1615-1617,共3页Chinese Journal of Experimental Surgery

基　　金：广东省科技计划基金资助项目（2008B060600059、2009B060700079）;广东省医学科学基金资助项目（A2009188）;教育部博士点新教师基金资助项目（20090171120077）;广东省自然科学基金资助项目（10151008901000084）;广东省大学生创新实验项目（1055810096）

摘　　要：目的 探讨在增龄过程中SD大鼠髓核组织中LAMP2A和MEF2D的表达及其意义.方法 3、12、24月龄SD大鼠各8只,建立青年大鼠组、中年大鼠组和老龄大鼠组模型,透射电镜检测髓核细胞中自噬体的表达 逆转录-聚合酶链反应（RT-PCR）和Western blot法测定髓核组织中LAMP2A和MEF2D的表达.结果 不同年龄组大鼠髓核细胞中均有自噬体的表达 RT-PCR和Western blot法显示LAMP2A在3、12、24月龄组中均有表达（0.91±0.07、1.12±0.11、1.32±0.28和0.45±0.06、0.55±0.08、0.63±0.11）,且在老龄组表达较青年组表达明显增高（P＜0.01和P＜0.05）,在3、12、24月龄组中,RT-PCR和Western blot法亦显示MEF2D均有表达（0.66±0.10、0.55±0.08、0.52±0.08和0.46±0.03、0.43±0.02、0.41±0.04）,且24月龄组表达明显较青年组低（P均＜0.01）.结论 自噬存在于椎间盘退变过程中 分子伴侣介导的自噬活性的增加可能与椎间盘退变的发展进程有关.LAMP2A介导的分子伴侣自噬性细胞死亡可能通过MEF2D进行调节.Objective To evaluate the expression and significance of LAMP2A and MEF2D in nucleus pulpous of rats during the aging process. Methods The models of youth, middle-aged and old rat were made with the 3-month, 12-month and 24-months SD rats respectively. The expression of autophagosome in nucleus pulpous was measured by transmission electron microscope （TEM）. The changes of LAMP2A and MEF2D in nucleus pulpous were measured by reverse transcription-polymerase chain reaction （RT-PCR） and western blotting. Results RT-PCR showed expression of LAMP-2A mRNA in 24- and 12-month group was higher than in 3-month group （1.32 ±0.28, 1.12 ±0. 11, vs 0.91 ±0.07 P〈0. 01, P 〈0. 01 ）, Western blotting also showed expression of LAMP-2A protein was higher in 24- and 12-month group than in 3-month group （0.63 ±0. 11, 0.55 ±0.08 vs 0.45 ±0.06 P〈0.01, P〈0. 05）. RT-PCR showed significantly lower expression of MEF2D mRNA in the 24- and 12-month rat nucleus pulposus than in 3-month group （0. 52 ± 0. 08, 0. 55 ± 0. 08 vs 0. 66 ± 0. 10 P 〈 0. 01, P 〈 0. 01 ）,Western blotting showed significantly lower expression of MEF2D protein in the 24-month rat nucleus pulposus than in 3-month group （0. 41 ±0. 04 vs 0. 46 ±0.03, P 〈0. 01 ）. Conclusion Autophagy was showed in the process of intervertebral disc degeneration. CMA pathway mediated by LAMP-2A may relate to process of the lumbar disc degeneration, the expression of LAMP2A was mediated by MEF2D.

关 键 词：椎间盘退变 增龄 分子伴侣介导的自噬 LAMP2A MEF2D 

分 类 号：R681.53[医药卫生—骨科学]