Bone Morphogenetic Protein-7 (BMP-7) Promotes Neuronal Differentiation of Bone Marrow Mesenchymal Stem Cells (BMSCs) In Vitro.

Heng Zhang,Guangchao Bai,Lei Gao,Wen Zhang,Kuanxin Li,Fernando José Dias

doi:10.1155/2021/7239783

Abstract

This study is aimed at investigating the effects of bone morphogenetic protein-7 (BMP-7) on the differentiation of bone marrow mesenchymal stem cells (BMSCs) into neuron-like cells in vitro. The rat BMSCs were isolated and identified, which were divided into the control, empty, recombinant rhBMP-7 transfection, and Lv-BMP-7 transfection groups. BMSCs were induced under different conditions. CCK-8 assay was performed to detect cell proliferation. ALP was used to detect cell activity. Cellular morphology after induction was observed. Immunofluorescence was conducted to detect the expression and location of nerve cell markers. Quantitative real-time PCR and Western blot analysis were performed to detect the mRNA and protein expression levels, respectively. The rhBMP-7 and Lv-BMP-7 promoted the proliferation of BMSCs, accompanied with increased ALP activities. Morphological observations revealed that rhBMP-7 and Lv-BMP-7 induced BMSCs to differentiate into neuron-like cells. Immunofluorescence revealed that the rhBMP-7 and Lv-BMP-7 groups showed positive expression of MAP-2 and Nfh in BMSCs. MAP-2 was mainly distributed in the cell body and cellular protrusion, while Nfh was mainly distributed in the cytoplasm and cell protrusion. Positive mRNA and protein expressions of MAP-2 and Nfh were observed in the cells of the rhBMP-7 and Lv-BMP-7 groups, and the expression levels were significantly higher than the control and empty groups. Both exogenous BMP-7 (rhBMP-7) and endogenous BMP-7 (Lv-BMP-7) can induce BMSCs to differentiate into neuron-like cells highly expressing the neuronal markers MAP-2 and Nfh.

Highlights

Spinal cord injury (SCI) is caused by direct physical damage to the spinal cord, which causes severe neurological dysfunction [1]
The results showed that the positive expression rate of CD29 on the surface of P2 bone marrow mesenchymal stem cells (BMSCs) was 99.44%, and the positive expression rate of CD44 was 99.17% (Figure 1(a))
The fluorescence intensity of the MOI = 10 group (12:40 ± 0:07) was significantly higher than the MOI = 25 (2:79 ± 0:05) and MOI = 50 (0:83 ± 0:02) groups (Figure 1(b)). These results suggest that MOI = 10 is the optimum multiplicity of infection for Lv-bone morphogenetic protein-7 (BMP-7)

Summary

Introduction

Spinal cord injury (SCI) is caused by direct physical damage to the spinal cord, which causes severe neurological dysfunction [1]. The researches concerning the treatment of SCI have been mainly focused on cell transplantation after SCI. Transplanted neuronal cells could supplement the neuronal loss in the damaged area and enhance the subsequent neurotrophic factor secretion, improving the microenvironment [2, 3]. Initial researches have mainly focused on transplanting MSC into the SCI animal model to replace the nerve cell loss within the lesions. A large number of studies have confirmed that the transplantation could improve the function of damaged nerves [4,5,6,7]

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Methods

Results