Characterization of PEG-SH modified GNPs/miR-29 nanoparticles and cytocompatibility
10.3760/cma.j.cn121113-20200629-00411
- VernacularTitle:巯基聚乙二醇修饰GNPs/miR-29纳米微粒的制备及细胞相容性研究
- Author:
Junming WAN
1
;
Shuang ZHU
;
Xiaobo XIE
;
Zhaowei LIN
;
Liangle LIU
;
Lijun LIN
;
Qi LI
Author Information
1. 浙江省立同德医院骨科，杭州 310002
- From:
Chinese Journal of Orthopaedics
2020;40(21):1478-1485
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To prepare PEG-SH modified GNPs/miR-29 nanoparticles and to investigate the proliferation and differentiation of neural stem cells induced by PEG-SH modified GNPs/miR-29 nanoparticles.Methods:PEG-SH modified GNPs/miR-29 nanoparticles were developed by oxidation-reduction method and were tested for UV absorption spectrum, particle size distribution and zeta potential of nanoparticles. A total of 15 adult male Sprague Dawley (SD) rats were used to establish spinal cord injury model by modified Allen method. The artificial miR-29 and PEG-SH modified GNPs/miR-29 nanoparticles were implanted into the injury site of spinal cord respectively. The stability of miR-29 expression was analyzed by gel electrophoresis. The neural stem cells were isolated and cultured from 10 SPF grade neonatal rats. It was identified by Nestin, GFAP and NSE antibodies. The activity and proliferation of neural stem cells in synthetic miR-29, PEG-SH GNPs and PEG-SH GNPs/miR-29 nanoparticles group was detected by CCK-8 assay. Neural stem cells were cultured with synthetic miR-29, PEG-SH GNPs and PEG-SH GNPs/miR-29 nanoparticles for 1 week. The density, length and number of neuritis were investigated.Results:The solution of PEG-SH modified GNPs showed a brownish red appearance. The spheres were in uniform distribution under transmission electron microscope. The results of UV absorption spectrum showed a single peak wave. The peak value of UV absorption was near 523 nm. The zeta potential increased gradually with the increased content of PEG-SH. The peak value of zeta potential was 22.5±5.2 mV. With the increase of content of PEG, the particle size of PEG-SH modified GNPs rapidly reached peak value at the early stage and then decreased rapidly to a relatively stable level. The synthetic miR-29 and PEG-SH modified GNPs/miR-29 nanoparticles were implanted into the injury site of spinal cord. At 0-6 h, clear band was observed in the synthetic miR-29 group. However, the band was disappeared rapidly at 12-24 h. In PEG-SH GNPs/miR-29 group, clear band were always observed. The OD values of miR-29 group were 0.34±0.17, 0.78±0.31, 1.28±0.68, 1.64±0.38 at 1, 3, 5 and 7 d after inoculation respectively. There was no significant difference in OD values compared with DMEM group. There was no significant difference in OD values among GNPs, PEG-SH GNPs, PEG-SH GNPs/miR-29 and DMEM group. The density (56.38±3.65 μm 2), length (78.25±3.72 μm) and the number [(356±34.52) /1,000×high power field] of neurites in PEG-SH GNPs/miR-29 group were higher than those in miR-29 group, PEG-SH modified GNPs group and saline group. However, there was no significant difference in the density, length and number of neurite between PEG-SH GNPs/miR-29 and serum group. Conclusion:PEG-SH modified GNPs/miR-29 nanoparticless have good biological properties. It can induce the proliferation and differentiation of neural stem cells with protective effects on miR-29.
