Transplantation of autologous sympathetic neurons as a potential strategy to restore metabolic functions of the damaged nigrostriatal dopamine nerve terminals in Parkinson's disease

Intrahippocampal Transplantation of Undifferentiated Human Chorionic- Derived Mesenchymal Stem Cells Does Not Improve Learning and Memory in the Rat Model of Sporadic Alzheimer Disease

BACKGROUND AND OBJECTIVE

Alzheimer's Disease (AD) is a progressive neurodegenerative disorder with consequent cognitive impairment and behavioral deficits. AD is characterized by loss of cholinergic neurons and the presence of beta-amyloid protein deposits. Stem cell transplantation seems to be a promising strategy for regeneration of defects in the brain.

METHOD

One of the suitable type of stem cells originated from fetal membrane is Chorion-derived Mesenchymal Stem Cells (C-MSCs). MSCs were isolated from chorion and characterized by Flowcytometric analysis. Then C-MSCs labeled with DiI were transplanted into the STZ induced Alzheimer disease model in rat.

RESULTS

Nissl staining and behavior test were used to assess the efficacy of the transplanted cells. Phenotypic and Flowcytometric studies showed that isolated cells were positive for mesenchymal stem cell marker panel with spindle like morphology.

CONCLUSION

Learning and memory abilities were not improved after stem cell transplantation. C-MSCs transplantation can successfully engraft in injured site but the efficacy and function of transplanted cells were not clinically satisfied.

Parkinson's disease research: adopting a more human perspective to accelerate advances

Parkinson's disease (PD) affects 1% of the population over 60 years old and, with global increases in the aging population, presents huge economic and societal burdens. The etiology of PD remains unknown; most cases are idiopathic, presumed to result from genetic and environmental risk factors. Despite 200 years since the first description of PD, the mechanisms behind initiation and progression of the characteristic neurodegenerative processes are not known. Here, we review progress and limitations of the multiple PD animal models available and identify advances that could be implemented to better understand pathological processes, improve disease outcome, and reduce dependence on animal models. Lessons learned from reducing animal use in PD research could serve as guideposts for wider biomedical research.

Neurotrophin-3 promotes proliferation and cholinergic neuronal differentiation of bone marrow- derived neural stem cells via notch signaling pathway

AIMS

Recently, the potential for neural stem cells (NSCs) to be used in the treatment of Alzheimer's disease (AD) has been reported; however, the therapeutic effects are modest by virtue of the low neural differentiation rate. In our study, we transfected bone marrow-derived NSCs (BM-NSCs) with Neurotrophin-3 (NT-3), a superactive neurotrophic factor that promotes neuronal survival, differentiation, and migration of neuronal cells, to investigate the effects of NT-3 gene overexpression on the proliferation and differentiation into cholinergic neuron of BM-NSCs in vitro and its possible molecular mechanism.

MAIN METHODS

BM-NSCs were generated from BM mesenchymal cells of adult C57BL/6 mice and cultured in vitro. After transfected with NT-3 gene, immunofluorescence and RT-PCR method were used to determine the ability of BM-NSCs on proliferation and differentiation into cholinergic neuron; Acetylcholine Assay Kit was used for acetylcholine (Ach). RT-PCR and WB analysis were used to characterize mRNA and protein level related to the Notch signaling pathway.

KEY FINDINGS

We found that NT-3 can promote the proliferation and differentiation of BM-NSCs into cholinergic neurons and elevate the levels of acetylcholine (ACh) in the supernatant. Furthermore, NT-3 gene overexpression increase the expression of Hes1, decreased the expression of Mash1 and Ngn1 during proliferation of BM-NSCs. Whereas, the expression of Hes1 was down-regulated, and Mash1 and Ngn1 expression were up-regulated during differentiation of BM-NSCs.

SIGNIFICANCE

Our findings support the prospect of using NT-3-transduced BM-NSCs in developing therapies for AD due to their equivalent therapeutic potential as subventricular zone-derived NSCs (SVZ-NSCs), greater accessibility, and autogenous attributes.

Transplantation of NSC-derived cholinergic neuron-like cells improves cognitive function in APP/PS1 transgenic mice

The ability to selectively control the differentiation of neural stem cells (NSCs) into cholinergic neurons in vivo would be an important step toward cell replacement therapy. First, green fluorescent protein (GFP)-NSCs were induced to differentiate into cholinergic neuron-like cells (CNLs) with retinoic acid (RA) pre-induction followed by nerve growth factor (NGF) induction. Then, these CNLs were transplanted into bilateral hippocampus of APP/PS1 transgenic mice. Behavioral parameters showed by Morris water maze (MWM) tests and the percentages of GFP-labeled cholinergic neurons of CNL transplanted mice were compared with those of controls. Brain levels of choline acetyltransferase (ChAT) mRNA and proteins were analyzed by quantitative real-time PCR and Western blotting, ChAT activity and acetylcholine (ACh) concentration were also evaluated by ChAT activity and ACh concentration assay kits. Immunofluorescence analysis showed that 80.3±1.5% NSCs differentiated into CNLs after RA pre-induction followed by NGF induction in vitro. Three months after transplantation, 82.4±6.3% CNLs differentiated into cholinergic neurons in vivo. APP/PS1 mice transplanted with CNLs showed a significant improvement in learning and memory ability compared with control groups at different time points. Furthermore, CNLs transplantation dramatically increased in the expressions of ChAT mRNA and protein, as well ChAT activity and ACh concentration in APP/PS1 mice. Our findings support the prospect of using NSC-derived CNLs in developing therapies for Alzheimer's disease (AD).

Engraftment of mouse embryonic stem cells differentiated by default leads to neuroprotection, behaviour revival and astrogliosis in parkinsonian rats

We report here protection against rotenone-induced behavioural dysfunction, striatal dopamine depletion and nigral neuronal loss, following intra-striatal transplantation of neurons differentiated from murine embryonic stem cells (mES). mES maintained in serum free medium exhibited increase in neuronal, and decrease in stem cell markers by 7th and 10th days as revealed by RT-PCR and immunoblot analyses. Tyrosine hydroxylase, NURR1, PITX3, LMX1b and c-RET mRNA showed a significant higher expression in differentiated cells than in mES. Dopamine level was increased by 3-fold on 10th day as compared to 7 days differentiated cells. Severity of rotenone-induced striatal dopamine loss was attenuated, and amphetamine-induced unilateral rotations were significantly reduced in animals transplanted with 7 days differentiated cells, but not in animals that received undifferentiated ES transplant. However, the ratio of contralateral to ipsilateral swings in elevated body swing test was significantly reduced in both the transplanted groups, as compared to control. Striatal grafts exhibited the presence of tyrosine hydroxylase positive cells, and the percentage of dopaminergic neurons in the substantia nigra was also found to be higher in the ipsilateral side of 7 days and mES grafted animals. Increased expression of CD11b and IBA-1, suggested a significant contribution of these microglia-derived factors in controlling the limited survival of the grafted cells. Astrocytosis in the grafted striatum, and significant increase in the levels of glial cell line derived neurotrophic factor may have contributed to the recovery observed in the hemiparkinsonian rats following transplantation.