Research Progress Of Parkinson's Stem Cells Treatment

Parkinson's disease（PD）is a chronic neurodegenerative disease that endangers the health of middle-aged and elderly people, and its incidence is second only to Alzheimer's disease. The main pathological feature of PD is the progressive loss of dopaminergic neurons（DN）in the substantia nigra in the brain, resulting in a lack of dopamine content in the striatum, resulting in dyskinesia. The incidence of PD is high in the elderly. With the aggravation of the aging of society, the number of PD patients is increasing year by year, which greatly affects the quality of life of patients, and brings a heavy burden to the society. Therefore, it is of great significance to find effective treatment methods.

At present, the main methods of clinical treatment of PD are drugs and surgery, but these two treatment methods can only relieve PD symptoms and cannot replace or regenerate the DN lost in the brain. Therefore, researchers try to treat PD by means of cell transplantation. Cell transplantation therapy is to use a specific way to transplant cells into a lesion or a specific site for tissue regeneration and repair to cure the disease. At present, there are various sources of parkinson's stem cells treatment, and different types of stem cells show their own advantages and disadvantages in the process of PD treatment. The following will specifically discuss the research on several common parkinson's stem cells treatment.

Embryonic stem cells（ESCs) transplantation for PD

Embryonic stem cells are isolated from early embryos and are the inner cell mass of a fertilized egg when it develops into a blastocyst. Many studies have confirmed that DN transplantation from ESCs can improve PD symptoms, but the in vitro differentiation mechanism of ESCs is not fully understood, and a stable induction and differentiation protocol needs to be established. ;At the same time, ESCs are allogeneic cells compared to PD patients, and immune rejection may occur in transplantation, and the acquisition of ESCs is controversial, which limits the development and application of ESCs. It is hoped that with the establishment of clinical-grade ESCs lines and cell matching technologies With the development of methods, ESCs can gradually break through the limitations of development and be applied to the clinic.

Neural stem cells（NSCs）transplantation for PD

NSCs have low species specificity, have pluripotency, self-renewal ability, and repair neural pathways.Compared with other cells, it has the advantages of less immune rejection and low tumorigenicity, which is beneficial to avoid immune rejection in allogeneic transplantation. Although NSCs have many advantages, there are still many problems in their wide application in clinical practice: ①NSCs derived from living patients are generally limited due to ethical restrictions; ②There are problems such as low number of survival and migration, slow maturation, instability of transplantation and uncertainty of efficacy, and the differentiation and repair mechanism of NSCs needs to be further explored; ③The formulation of personalized treatment plans for PD patients and the long-term efficacy Further research is required.

Induced pluripotent stem cells（iPSCs）for PD

Induced pluripotent stem cells are somatic cells transformed into pluripotent stem cells similar to ESCs after reprogramming. iPSCs are very similar to ESCs in terms of gene protein expression and proliferation and differentiation ability. Compared with ESCs, iPSCs have a rich source of somatic cells, which can avoid ethical issues and immunity to a certain extent. iPSCs have broad application prospects in cell replacement therapy, disease model mechanism research and drug screening. Although iPSCs technology has developed rapidly in recent years, there are still many problems that need to be solved urgently: ①The molecular mechanism of somatic cell reprogramming technology is not fully understood, and the safety of hiPSCs in clinical application remains to be explored; ②Self-renewal and induced differentiation of stem cells The mechanism is still in the research stage, and the efficiency and stability of directed differentiation in vitro still need to be improved.

Stem cells are a kind of pluripotent cells with self-renewal and differentiation ability. They are divided into totipotent stem cells, pluripotent stem cells and multipotent stem cells according to the different differentiation potential of cells, and embryonic stem cells and adult stem cells according to the different stages of cell development. With the successful establishment of various experimental models and the rapid development of transplantation technology, a series of breakthrough results have been achieved in parkinson's stem cells treatment. Different types and sources of stem cells can play a role in nerve regeneration and repair in PD treatment, but parkinson's stem cells treatment and its widespread clinical application still require a long period of trials and observations. It is hoped that with the continuous development and progress of scientific research and medical technology, parkinson's stem cells treatment can be widely used in clinic to relieve the pain.