多能成体祖细胞移植治疗帕金森病及其作用机制

Mechanisms restoring cerebral function of bone marrow mnitipotent adult progenitor cells after transplantation in Parkinson＇ s disease rat models

目的探讨骨髓间质分离的多能成体祖细胞（MAPCs）移植后在大鼠脑组织内神经细胞分化及修复神经功能的作用机制。方法制作帕金森病大鼠模型，将在体外纯化、增殖和已用5-溴-2脱氧尿苷（BrdUrd）处理过的MAPCs注入帕金森病大鼠脑内。3个月后，对移植大鼠采用免疫组织化学技术、逆转录－聚合酶链反应（RT-PCR）、行为学测试等方法鉴定和分析MAPCs在大鼠脑组织内神经元样细胞分化和修复神经功能的作用机制。结果6-羟多巴诱导的大鼠行为学变化MAPCs组明显好于对照组；细胞移植后第4、8、12周时，移植的PD大鼠1h内的旋转圈数为对照组（687．8±2．7、754．1±13．4、763．2±14．8）和MAPCs组（528．0±12．7、440．5±12．0、435．0±7．1）。MAPCs在中脑黑质和纹状体区分化为神经元样细胞和多巴胺能神经元；PCR检查发现多巴胺－β-羟化酶、多巴胺转运体和神经生长因子表达水平MAPCs组（分别为0．510±0，028、0．620±0．046、0．850±0．051）明显比对照组（分别为0．310±0．072、0．400±0．044、0．480±0．057）升高（P〈0．05）。结论骨髓间质分离的MAPCs移植后能在大鼠脑组织微环境中自主分化为多巴胺能神经细胞并有效地修复6-羟多巴诱导的神经功能缺损。

Objective To explore the mechanisms that bone marrow derived-muhipotent adult progenitor cells （MAPCs） transplant into the brain and differentiated into neuron cells reduce neurological functional deficits in rats. Methods We establish successfully rat models of parkinson＇ s disease, sequentially,we injected MAPCs into left striatum, for cellular identification, MAPCs were prelabeled with bromodeoxyuridine（BrdUrd）. By three months post-injection, behavioral tests, immuno-fluorescence method, reverse transcription-polymerase chain reaction （RT-PCR） were used to evaluate and analyze that MAPCs differentiate into neuron-hke cells and how MAPCs restore cerebral function. Results Compared with control animals, MAPCs-derived DA neurons caused gradual and sustained behavioral restoration of DA-mediated motor asymmetry, at the 4th/8th/12th week after cell transplantation, the rotation turns within 1 hour of control group were 687. 8 ±2. 7,754. 1 ± 13.4,763.2 ±14. 8 respectively,while that of MAPCs group were 528.0 ±12.7,440. 5 ±12.0,435.0 ±7. 1 respectively （ P 〈 0. 05 ）. After implantation, MAPCs could survive and differentiate into neuron-like cells in substantia nigra and striatum, including dopamine-neurons. Real-time PCR revealed significantly higher DBH（ 1.64-fold increase）, DAT（ 1.55-fold increase） and NGF （ 1.77-fold increase） mRNA levels in the MAPCs group, which suggested MAPCs derived neurons could performed the function of dopamine neurons. Conclusion These results demonstrate that transplanted MAPCs can develop spontaneously into DA neurons. Such DA neurons can restore cerebral function and be- havior in rat models of Parkinson＇ s disease.