Neural stem cells as therapeutic agents for treatments of Parkinson's disease in rat model

Abstract

Parkinson's disease (PD) is the second most common neurodegenerative disease. With the rapid global increase in population aging, neurodegenerative diseases are considered a primary threat to human health. As dopaminergic neuronal cell death and dysfunction are the main pathogenic mechanisms of PD, neural stem cell (NSC) replacement therapy has been identified as a potentially effective and indeed ideal therapeutic strategy. However, current in vitro stem cell culture methods, which require various chemical growth factors (GFs), are unsafe and relatively inefficient. To solve this problem, we developed two strategies for enhancing the proliferation and differentiation of NSCs in vitro based on extracellular nanomatrices and natural active ingredients. First, we developed novel nanomatrices comprising biomaterials used for promoting NSCs proliferation and differentiation without requiring additional GFs. We developed two types of inorganic sculptured extracellular nanomatrices comprising SiO2 (iSECnMs) which deposited by glancing angle deposition (GLAD). The physiological properties of nanomatrices mediate the activation of multiple bio-signaling pathways. Accordingly, iSECnMs, especially those sculptured in zigzag forms, can significantly promote the proliferation and specific neuronal phenotypic differentiation of NSCs without requiring additional GFs. The differentiated neurons survived well in vivo and achieved outstanding therapeutic effects in a rat model of 6-OHDA-induced parkinsonism. Second, 20(S)-protopanaxadiol (PPD) and oleanolic acid (OA), two crucial active ingredients derived from ginseng, significantly enhanced the proliferation and neuronal differentiation of NSCs through activating Wnt/GSK-3β/β-catenin pathway. This research is expected to promote significant developments in the induction of NSCs and provide insights into stem cell therapies for PD without undesirable prognoses