干细胞移植治疗帕金森病研究进展

帕金森病(Parkinson's disease,PD)是一种人类常见的中枢神经系统退行性疾病,主要病理变化是黑质内多巴胺神经元损伤,是干细胞治疗的最佳适应证之一.动物模型的研究证实,干细胞移植可以替代丧失的神经元,恢复脑功能和促进脑的自我修复.临床试验显示干细胞移植在PD病人脑部也可达到类似的结果.这些研究展示了干细胞移植临床应用治疗PD的良好前景.然而,这样的治疗是否可以永久和完全恢复PD的脑功能仍是一个疑问.     

骨髓间质干细胞移植治疗帕金森病的研究进展

骨髓间质干细胞(mesenchymal stem cells,MSCs)具有自我更新、高度增殖的特性,并且可以在体外分化为多巴胺能神经元。本文从MSCs体外定向分化为多巴胺能神经元、MSCs的转基因操作及MSCs移植治疗帕金森病(Parkinson'sdisease,PD),三个方面来综述近期的MSCs移植治疗PD的研究进展。实验研究证实,帕金森病动物移植骨髓间质干细胞后症状可以改善,相信MSCs是治愈PD的希望所在。     

帕金森病的细胞治疗

帕金森病（PD）是一种中脑黑质多巴胺能神经元进行性退化导致黑质-纹状体通路受损的中枢神经系统退行性疾病。目前主要治疗方式是多巴胺能药物和深部脑刺激（DBS）,但这两种治疗方案只能暂时缓解症状并不能完全根治且有不良反应。干细胞具有自我更新和多向分化的潜能,干细胞移植能够修复受损的组织,为PD的治疗带来了曙光。本文介绍了细胞移植治疗帕金森病的研究进展。     

细胞移植治疗帕金森病移植细胞的选择与调控

帕金森病(Parkinson disease,PD)是以中脑多巴胺(DA)神经元丢失为特征的中机神经系统退行性疾病.近年来,干细胞移植技术、体外培养诱导分化技术日渐成熟,为神经细胞脑内移植治疗神经系统退行性病变提供更广阔的前景.本文主要从移植细胞的来源和移植的调控方面对近年来国内外神经细胞脑内移植治疗帕金森病的新进展进...     

AADC和NURR1基因联合c17.2神经干细胞移植治疗帕金森病的实验研究

目的研究芳香族氨基酸脱羧酶(AADC)基因和NURR1基因联合c17．2神经干细胞脑内移植后对帕金森病模型大鼠的治疗效果。方法人类神经元性AADC基因和NURR1基因真核表达载体分别转染至c17．2神经干细胞内。将帕金森病(PD)模型大鼠随机分为4组,分别予以脑内毁损侧纹状区移植含空质粒的c17．2神经干细胞(A组),pCDNA3-AADC转染后的c17．2神经干细胞(B组),pCDNA3-NURR1转染后的c17．2神经干细胞(C组)以及含有pCDNA3-AADC和pCDNA3-NURR1转染后的c17．2 神经干细胞(D组)。观察其病理性旋转行为的改善,采用酪氨酸羟化酶(TH)的免疫组化方法研究脑内多巴胺含量的变化,并用荧光示踪方法观察c17．2细胞在PD模型脑内的移行。结果各组动物脑内移植后动物旋转行为较前均有改善(P<0．05),尤以D组改善最为明显,其行为学最大改善达73．7％,且同A、B、C组间差异具有显著性(P<0．05)。免疫组化可见各组移植TH阳性细胞明显增多,TH染色的神经元树突或轴突密集,体内TH阳性区域明显较PD模型组扩大,其中尤以D组病理学改善最为明显。荧光示踪观察c17．2神经干细胞有突触形成,并与临近的细胞建立突触联系。结论 AADC基因联合NURR1基因共转染c17．2神经干细胞脑内移植后改善了动物的旋转行为,增加了脑内多巴胺的表达,且植入的神经干细胞可同宿主神经元形成突触联接,为研究多基因联合神经干细胞移植治疗帕金森病提供了新方法。     

神经干细胞与帕金森病

神经干细胞具有几乎无限的稳定扩增能力以及体外分化为多巴胺能神经元的能力,使之成为神经变性疾病移植治疗的重要细胞来源。神经干细胞可以在宿主脑内增殖、分化、迁移并与宿主神经组织整合。移植后的神经干细胞系在体内特定环境下可以自发地表达多巴胺能神经元的特性。可以通过刺激成年哺乳动物脑内终生存在的神经干细胞,使之在脑内增殖、迁移,并分化为多巴胺能神经元,与周围建立突触联系以治疗帕金森病。神经干细胞治疗帕金森病的前景是巨大的,但距临床应用尚有一定距离,仍需要包括动物实验在内的大量基础研究。     

基因修饰骨髓源性神经元样干细胞治疗帕金森大鼠的研究

目的 观察大鼠酪氨酸羟化酶(tyrosinehydroxylase,TH)修饰的骨髓基质源性神经元样干细胞(neuronoid stem cells derived from bone marrow stem cells,NdSCs-D-BMSCs)在脑室移植途径下对帕金森病(Parkinson disease,PD)大鼠的治疗作用.方法 将酶切鉴定后的新构建质粒pEGFP-C2-TH经电穿孔法转染培养第8天NdSCs-D-BMSCs,注射到PD大鼠模型右侧脑室,观察大鼠行为学变化,移植细胞在大鼠脑组织内的迁移,以及高效液相方法检测脑内DA含量.结果 质粒pEGFP-C2-TH转染NdSCs-D-BMSCs移植后10周,PD大鼠症状显著改善,DA恢复至正常水平33.0%,移植细胞可以在PD大鼠脑内存活,并出现远处迁移.结论 TH修饰的大鼠NdSCs-D-BMSCs经脑室移植对PD大鼠具有明显的治疗作用,为临床中腰椎穿刺干细胞移植的应用提供实验依据.     

基因修饰的神经干细胞与帕金森病

神经干细胞具备自我更新能力，可在特定环境下定向分化为神经元和胶质细胞，通过分泌神经营养因子、调控神经炎症、增强神经元可塑性等机制修复帕金森病(PD)多巴胺神经元损伤。目前PD治疗主要是多巴胺替代治疗，但不能阻止PD病情进展，且不能彻底根治。干细胞在PD中具有较好的治疗前景，尤其神经干细胞优势引起较多关注。尽管神经干细胞移植在PD治疗中取得了一定的效果，但临床中的应用仍受到很多条件限制。本文就神经干细胞基因修饰在PD治疗中的研究进展进行综述，旨在探讨神经干细胞治疗PD的关键调控机制。     

干细胞治疗在帕金森病中的应用

帕金森病(PD)是常见于中老年人的慢性进行性神经系统退行性疾病,目前虽然有多种方法可用于缓解其症状,如长期药物治疗、外科手术治疗等,但是这些方法因为治疗效果有限、并发症严重而难以推广和应用.近年来应用干细胞移植治疗PD得到了越来越多的关注.因此,本文将就不同类型干细胞的生物学特性,定向诱导分化为多巴胺能神经元的方法,移植治疗PD的基础研究进展和临床探索以厦移植治疗的局限性进行综述,旨在为干细胞移植治疗PD提供科学依据.     

帕金森病移植神经元凋亡的研究进展

自 1 979年 Perlow等人采用胚腹侧中脑 (ven-tral mesencephalon,VM)组织移植入帕金森病(PD)模型鼠脑内 ,发现移植物中的多巴胺 (DA)神经元修复了损害引起的功能缺损。自此以后脑内移植给病人的治疗带来了新的希望。 1 987年 Bjoklund首先用胚 VM组织治疗 PD病人获得成功。迄今为止全世界已有很多患者接受该术治疗 ,观察表明该方法能有效地缓解病人的临床症状 [1,2 ] ,但是病人的功能并没有完全恢复。Zawada等 [3 ] 人发现移植后的神经元大多数在头三天已经发生凋亡。因此 ,弄清移植神经元凋亡的原因以及如何阻止其凋亡已成为该研究领…     

Development of stem cell-based therapies for Parkinson's disease

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the progressive loss of dopaminergic neurons of the substantia nigra pars compacta in the brain with an unknown cause. Current pharmacological treatments for PD are only symptomatic and there is still no cure for this disease nowadays. In fact, transplantation of human fetal ventral midbrain cells into PD brains has provided a proof of concept that cell replacement therapy can be used for some PD patients, beneficial for improving their symptoms. However, the ethical and practical issues of human fetal tissue will inevitably limit its widespread clinical use. Therefore, it is essential to find alternative cell sources for the future cell transplantation for PD patients. With recent development in stem cell technology, here, we review the different types of stem cells and their main properties currently explored, which could be developed as a possible cell therapy for PD treatment.     

Cell transplantation in the damaged adult brain

Parkinson's disease (PD) is the most common movement disorder in Europe, affecting more than two million people between 50 and 70 years of age. The current therapeutic approaches are of symptomatic nature and fail to halt the progressive neurodegenerative course of the disease. The development of innovative and complementary approaches to promote cellular repair may pave the way for disease-modifying therapies which may lead to less suffering for the patients and their families and finally to more cost-effective therapies. To date, cell replacement trials in PD aiming at replacing lost dopamine neurons were mainly focused on placing the transplanted cells within the target site, the striatum, and not within the lesioned site, the substantia nigra (SN). This was based on the misconception that the adult brain constitutes a non-permissive barrier not allowing the outgrowth of long distance axons originating from transplanted embryonic neurons. A growing body of evidence is challenging this concept and proposing instead to place the graft within its ontogenic site. This has been performed in several lesional animal models for various traumatic or neurodegenerative pathologies of the brain. For instance, transplanted neurons within the lesioned motor cortex were shown to be able to send distant and appropriate projections to target areas including the spinal cord. Similarly, in an animal model of PD, mesencephalic embryonic cells transplanted within the lesioned SN send massive projections to the striatum and, to a lesser extent, the frontal cortex and the nucleus accumbens. This has lead to the proposal that homotopic transplantation may be an alternative in cell-based therapies as transplanted neurons can integrate within the host brain, send projections to target areas, restore the damaged circuitry, increase neurotransmitter levels and ameliorate behavior. We will discuss also the potential of replacing embryonic neuronal cells by stem cell derived neurons as the use of embryonic cells is not without an ethical and logistical burden; in this line many have thrived to derive neurons from embryonic stem cells (ESC) in order to use them for cell transplantation. These studies are already yielding important information for future approaches in the field of cell therapies in PD but also in other neurodegenerative disorders where cell transplantation therapy may be considered. While the field of cell replacement therapies has been recently called into question with contrasting results in transplanted PD patients, these new sets of findings are raising new hopes and opening new avenues in this rejuvenated field.     

Viral vector-mediated gene therapy for Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects 1% of the population above the age of 60. The cause of the disease remains unknown. The histopathological hallmarks of the disease are intracytoplasmic Lewy bodies and dopaminergic striatal insufficiency secondary to a loss of dopaminergic neurons in the substantia nigra pars compacta (SN). Pharmacological treatment options for PD are often limited by the ability of prodopaminergic drugs to function within the nigrostriatal system, without activating other dopaminergic, but non-nigrostriatal regions, of the CNS. Even if this obstacle is overcome, considerations regarding the chronic availability of the drug can limit drug utility. Gene delivery systems are ideal for delivering therapeutic molecules to site specific regions of the CNS. Via gene therapy, a piece or pieces of DNA placed into a carrying vector encoding for a substance of interest is introduced into cells. While there are many ways to apply this technology, this review will focus on in vivo gene therapy as it applies to Parkinson's disease. Using stereotaxic surgery, vectors can be introduced into specific target areas in the brain and deliver genes encoding for therapeutic molecules. By delivering genes using gene therapy approaches, a therapeutic molecule can be delivered chronically in a site-specific fashion, diminishing unwanted side effects and repeated interventions to obtain useful levels of the drug. Throughout this review, we discuss the potential for gene delivery aimed at enhancing dopamine production or providing neuroprotection for nigrostriatal neurons to serve as a therapeutic strategy for PD.     

Neuromodulation for Parkinson's disease]

Parkinson's disease (PD) is a neurodegenerative disorder characterized by a progressive loss of midbrain dopaminergic (DA) neurons and a subsequent reduction in striatal dopamine. As a treatment for advanced Parkinson's disease, deep brain stimulation (DBS) of the thalamus was introduced in 1987 to treat tremor, and was applied in 1993 to the subthalamic nucleus. Now high-frequency stimulation of the subthalamic nucleus has become a surgical therapy of choice. Another surgical treatment is a cell replacement therapy. Transplantation of fetal dopaminergic (DA) neurons can produce symptomatic relief, however, the technical and ethical difficulties in obtaining sufficient and appropriate donor fetal brain tissue have limited the application of this therapy. Then, neural precursor cells and embryonic stem (ES) cells are expected to be candidates of potential donor cells for transplantation. We induced DA neurons from monkey ES cells, and analyzed the effect of transplantation of the DA neurons into MPTP-treated monkeys as a primate model of Parkinson's disease. Behavioral studies and functional imaging revealed that the transplanted cells functioned as DA neurons, attenuating the MPTP-induced neurological symptoms. DA neurons have also been generated from several human ES cell lines. Furthermore, functional recovery of rat PD models after transplantation was observed. One of the major problems in ES cell transplantation is tumor formation, which is caused by a small fraction of undifferentiated ES cells in the graft. So, it is essential for undifferentiated ES cells to be eliminated from the graft in order for transplantation to be feasible. These efforts will lead to clinical application of ES cell transplantation to the patients with PD.     

Neural stem cell‐based treatment for neurodegenerative diseases

Human neurodegenrative diseases such as Parkinson's disease (PD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS) and Alzheimer's disease (AD) are caused by a loss of neurons and glia in the brain or spinal cord. Neurons and glial cells have successfully been generated from stem cells such as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs) and neural stem cells (NSCs), and stem cell‐based cell therapies for neurodegenerative diseases have been developed. A recent advance in generatioin of a new class of pluripotent stem cells, induced pluripotent stem cells (iPSCs), derived from patients' own skin fibroblasts, opens doors for a totally new field of personalized medicine. Transplantation of NSCs, neurons or glia generated from stem cells in animal models of neurodegenrative diseases, including PD, HD, ALS and AD, demonstrates clinical improvement and also life extension of these animals. Additional therapeutic benefits in these animals can be provided by stem cell‐mediated gene transfer of therapeutic genes such as neurotrophic factors and enzymes. Although further research is still needed, cell and gene therapy based on stem cells, particularly using neurons and glia derived from iPSCs, ESCs or NSCs, will become a routine treatment for patients suffering from neurodegenerative diseases and also stroke and spinal cord injury.     

Stem cell‐based cell therapy in neurological diseases: A review

Human neurological disorders such as Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis (ALS), Alzheimer's disease, multiple sclerosis (MS), stroke, and spinal cord injury are caused by a loss of neurons and glial cells in the brain or spinal cord. Cell replacement therapy and gene transfer to the diseased or injured brain have provided the basis for the development of potentially powerful new therapeutic strategies for a broad spectrum of human neurological diseases. However, the paucity of suitable cell types for cell replacement therapy in patients suffering from neurological disorders has hampered the development of this promising therapeutic approach. In recent years, neurons and glial cells have successfully been generated from stem cells such as embryonic stem cells, mesenchymal stem cells, and neural stem cells, and extensive efforts by investigators to develop stem cell‐based brain transplantation therapies have been carried out. We review here notable experimental and preclinical studies previously published involving stem cell‐based cell and gene therapies for Parkinson's disease, Huntington's disease, ALS, Alzheimer's disease, MS, stroke, spinal cord injury, brain tumor, and lysosomal storage diseases and discuss the future prospects for stem cell therapy of neurological disorders in the clinical setting. There are still many obstacles to be overcome before clinical application of cell therapy in neurological disease patients is adopted: 1) it is still uncertain what kind of stem cells would be an ideal source for cellular grafts, and 2) the mechanism by which transplantation of stem cells leads to an enhanced functional recovery and structural reorganization must to be better understood. Steady and solid progress in stem cell research in both basic and preclinical settings should support the hope for development of stem cell‐based cell therapies for neurological diseases. © 2009 Wiley‐Liss, Inc.     

Recent Advances in the Development of Stem-Cell-Derived Dopaminergic Neuronal Transplant Therapies for Parkinson's Disease

The last decade has seen exciting advances in the development of potential stem cell-based therapies for Parkinson's disease (PD), which have used different types of stem cells as starting material. These cells have been developed primarily to replace dopamine-producing neurons in the substantia nigra that are progressively lost in the disease process. The aim is to largely restore lost motor functions, whilst not ever being curative. We discuss cell-based strategies that will have to fulfill important criteria to become effective and competitive therapies for PD. These criteria include reproducibly producing sufficient numbers of cells with an authentic substantia nigra dopamine neuron A9 phenotype, which can integrate into the host brain after transplantation and form synapses (considered crucial for long-term functional benefits). Furthermore, it is essential that transplanted cells exhibit no, or only very low levels of, proliferation without tumor formation at the site of grafting. Cumulative research has shown that stem cell-based approaches continue to have great potential in PD, but key questions remain to be answered. Here, we review the most recent progress in research on stem cell-based dopamine neuron replacement therapy for PD and briefly discuss what the immediate future might hold. © 2021 International Parkinson and Movement Disorder Society     

Transplants of neurosphere cell suspensions from aged mice are functional in the mouse model of Parkinson's

Neural stem cell therapy has the potential to treat neurodegenerative disorders. For Parkinson's disease (PD), the goal is to enhance the dopamine system sufficiently to restore the control of movement and motor activities. In consideration of autologous stem cell therapy for PD, it will be necessary to propagate the cells in most cases from aged brain tissue. We isolated cells from the subventricular zone (SVZ) in the brains of 1-year-old enhanced green fluorescent protein (GFP) mice and generated neurospheres in culture. Neurospheres yielding high numbers of neurons and astrocytes "de novo" were selected and cryopreserved before evaluating the efficacy of neurosphere cell suspensions transplanted to the 6-hydroxydopamine (6-OHDA) model of PD. In mice unilaterally lesioned with 6-OHDA, transplants of neurosphere cell suspensions to the striatum yielded astrocytes and tyrosine hydroxylase positive neurons that reduced or reversed the drug-induced behavioral circling response to amphetamine and apomorphine. Control mice without the cell suspensions showed no change in the motor behavior. Our results indicate that the SVZ in the aged mouse brain contains cells that can be expanded in the form of neurospheres, cryopreserved, re-expanded and then transplanted into the damaged dopamine system to generate functional cell progeny that offset the motor disturbances in the nigrostriatal system.