Human umbilical mesenchymal stem cells enhance the expression of neurotrophic factors and protect ataxic mice

Cerebellar ataxias, which comprise a wide spectrum of progressive disorders, are incurable at present. It has been reported that human umbilical mesenchymal stem cell (HU-MSC) transplantation has a protective effect on neurodegenerative diseases. In this study, we investigated the effect of HU-MSCs on ataxic mice induced by cytosine beta-D-arabinofuranoside (Ara-C). The ataxic mouse received an intravenous injection of 2 × 106 HU-MSCs once a week for three consecutive weeks. Neurological function was scored weekly by rotarod test and open field test. The mouse cerebellar volume and weight were also measured. The apoptotic cells, pathological alternations and distribution of HU-MSCs were determined by TUNEL assay and immunohistochemistry staining respectively. Double immunostaining was carried out to investigate the dynamics of HU-MSCs in the host animals. Neurotrophic factors in cerebellar tissue and serum were measured by Q-PCR and ELISA. Our results showed that HU-MSCs implantation significantly improved the motor skills of ataxic mice 8 weeks after application. HU-MSCs also alleviated cerebellar atrophy and decreased the number of apoptotic cells in the therapeutic group. Implanted HU-MSCs stayed in cerebellum for at least three months with no obvious differentiation. HU-MSC treated mice had enhanced expression of insulin-like growth factor-1 (IGF-1) and vascular endothelial growth factor (VEGF) in cerebellum extraction and blood serum. Double immunostaining revealed that a few MAB1287 positive cells co-localized with IGF-1 or VEGF express cells. Our results suggest that HU-MSC treatment is capable of alleviating the motor impairments and cerebellar atrophy in the ataxic mouse model, probably via promoting particular neurotrophic factors.

Research highlights
► Intravenous infusion of HU-MSCs to ataxic mice alleviated behavior impairment and morphologic atrophy.
► No obvious differential hint was observed in the existing HU-MSCs in host mice.
► The benefit was probably ascribed to the enhancement of IGF-1 and VEGF.