Background & objective: Parkinson's disease (PD) is a progressive neurodegenerative disorder in which the cause is attributed to the alpha-synuclein (α-Syn) accumulation due to the decreased rate of autophagy. Due to the many advantages, mesenchymal stem cells (MSCs), such as the secretion of neurotrophic factors, have been proposed for PD cell therapy. The present study, in continuation of the previous study, aimed to investigate the therapeutic effect of human-derived Conjunctival MSCs (CJ-MSCs) on the clearance of α-Syn by the microRNA-149(miR-149)/Akt/mTOR/ pathway.
Methods: Stereotaxic 6-hydroxy dopamine (6-OHDA) was injected directly into the medial forebrain bundle (MFB) to induce Parkinson's disease. An apomorphine-induced rotation test was used to confirm the model establishment. CJ-MSCs were encapsulated in alginate microgel using a microfluidic system. The green fluorescent protein (GFP) labeled CJ-MSCs were encapsulated, and free cells were transplanted into the rats' right striatum. Behavioral and molecular analyses evaluated the potency of CJ-MSCs (encapsulated and free cells) in PD rats. Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) was performed to investigate the expression of the miR-149-5p, Akt, mTOR, and α-Syn.
Results: Our obtained results indicated that transplantation of CJ-MSCs leads to a decrease in the number of rotations while raising the balance and motor abilities. The gene expression evaluation showed a significant reduction in Akt, mTOR, and α-Syn mRNA levels and a significant increase in the level of miR-149-5p compared to the control group.
Conclusion: It seems that CJ-MSCs can promote the degradation of intracellular α-Syn by miR-149-5p/Akt/mTOR pathway and improve rats' motor functions.
Keywords: Alpha-synuclein; Mesenchymal stem cells; Parkinson's disease; mTOR; miR-149-5p.