Induced Pluripotent Stem Cells Exosomes Protective Effect On Parkinson’s Disease Mice

Background:Parkinson’s disease is a neurodegenerative disease that cannot be completely treated at present.Current treatment methods can only delay the progression of the disease and focus on improving the quality of life of patients.There are several cell transplantation treatments for Parkinson’s disease,with varying degrees of progress in rodents and primates,but safety concerns remain.Exosomes are vesicles of a certain diameter secreted by cells.They contain a variety of proteins and nucleic acid molecules which play an important role in the physiological regulation of living organisms.At present,the exosomes of induced pluripotent stem cells have been extensively studied in various diseases,but no similar articles have been reported for Parkinson’s disease.Objective:To investigate whether induced pluripotent stem cell exosomes can relieve the symptoms of the Parkinson’s disease mouse model and to some extent reduce the loss of dopamine neurons in the substantia nigra.Methods:First,we constructed a Parkinson’s cell model of SH-SY5 Y cell apoptosis induced by 6-OHDA.Then,confocal laser assay was performed to determine the uptake of exosomes by cells.Then,flow cytometry and Western Blot were used to investigate the cell apoptosis.In terms of animal experiments,a mouse Parkinson’s disease model was constructed with a stereo location device,and the distribution of exosomes in vivo was analyzed with a small animal living imaging instrument.After that,the effects of exosomes on the loss of neurons in the midbrain of mice were explored by Western Blot,HE staining,nissel staining,immunohistochemistry and other experiments.Results:We used cell proliferation assay to determine the induction condition of our cell model at 125 μM 6-OHDA concentration and 24 h induction time,and selected 40 μg/m L exosomes for treatment of our cell model.Laser confocal analysis showed that exosomes could be uptaked by SH-SY5 Y cells.Flow cytometry and Western Blot analysis observed the phenomenon of apoptosis and found that the expression of apoptosis-promoting protein Bax was down-regulated and the expression of apoptosis-inhibiting protein Bcl-2 was upregulated.In terms of animal experiments,we used stereo localization device to model Parkinson’s disease mice.According to the small animal imaging device,exosomes can reach the brain of mice.HE staining,nissel staining and immunohistochemical results of tyrosine hydroxylase showed that the inflammatory infiltration of Parkinson’s mice after exosomes treatment was reduced and the recovery of dopamine neurons in the midbrain was increased.The experimental results of Western Blot in animal experiments were consistent with that of cell experiments.The final safety results indicate that the use of induced pluripotent stem cell exosomes in the treatment of mouse models of Parkinson’s disease can be considered safe.Conclusion: Induced pluripotent stem cell exosomes,as a kind of microclonal vesicle with great therapeutic potential,can inhibit apoptosis in mouse Parkinson’s disease model and provide a certain degree of neuroprotective effect.This study may provide a new solution for the progressive loss of Parkinson’s disease neurons.