Effect of exosome derived micro RNA-124 on activation status of microglia cells at acute phase of traumatic brain injury
10.3760/cma.j.issn.1671-8925.2018.12.001
- VernacularTitle:外泌体源性miR-124对创伤性脑损伤急性期小胶质细胞活化状态的作用研究
- Author:
Yongxiang YANG
1
;
Yuqin YE
;
Xinhong SU
;
Xin ZHANG
;
Chuiguang KONG
;
Wei BAI
;
Xiaosheng HE
Author Information
1. 空军军医大学(第四军医大学)西京医院神经外科
- Keywords:
Exosome;
Micro RNA-124;
Traumatic brain injury;
Microglia cell;
Activation
- From:
Chinese Journal of Neuromedicine
2018;17(12):1189-1194
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effect of exosome derived micro RNA (miR)-124 on activation status of microglia cells in injured brain tissues at acute phase of traumatic brain injury (TBI), and further provide theoretical references for intervention of neuroinflammation after TBI. Methods (1) In vitro cultured HEK293 cells were divided into miR-124 transfected group and control group, and miR-124 plasmids or Control siRNA by plasmid were transfected into the cells of the two groups;two-three weeks after isolation of monoclonal cell lines and two weeks after continuous culture, reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the miR-124 content in cells of the two groups; the exosomes were extracted from the supernatant of cells from the two groups using SBI kit, and the morphology of the exosomes was observed under electron microscope; the expression of CD63, a surface marker molecule, was detected by Western blotting; RT-PCR was used to determine the miR-124 content in the exosomes of the two groups. (2) A total of 60 healthy male rats were randomly divided into sham-operated group (n=12), TBI group (n=12) and TBI+Exo-124 group (n=24); TBI models were constructed by controlled cortical injury device, and Exo-124 (3×109 particles) was given into the TBI+Exo-124 group via tail intravenous injection and equivalent solvent was given to the sham-operated group and TBI group 24 h after TBI; 3 d after modeling, RT-PCR was used to detect the miR-124 expression in brain tissues of the injured areas of the three groups; flow cytometry (FCM) was used to detect the percentages of Iba-1+/CD32+ and Iba-1+/CD206+ microglial cells in brain tissues; enzyme-linked immunosorbent assay (ELISA) was used to detect the expressions of interleukin (IL)-1, IL-6, IL-4 and IL-10 in the brain tissues. Results (1) RT-PCR showed that the miR-124 expression in the miR-124 transfected group was statistically higher than that in the control group (P<0.05); electron microscopy showed spherical particles with diameter about 100 nm and obvious membrane structure; Western blotting showed that the expression level of CD63 in the miR-124 transfected group was significantly higher than that in the control group (P<0.05); RT-PCR showed that the miR-124 content in the miR-124 transfected group was significantly higher than that in the control group (P<0.05). (2) The miR-124 expression in injured brain tissues of TBI+Exo-124 group was statistically higher than that in TBI group and sham-operated group (P<0.05); as compared with those in the sham-operated group, the percentages of Iba-1+/CD32+ and Iba-1+/CD206+ microglial cells and the expressions of IL-1, IL-6, IL-4 and IL-10 in the brain tissues of TBI group were significantly increased (P<0.05); as compared with the TBI group, the TBI+Exo-124 group had significantly decreased percentage of Iba-1+/CD32+ microglial cells and significantly increased percentage of Iba-1+/CD206+ microglial cells, statistically decreased IL-1 and IL-6 expressions, and statistically increased IL-4 and IL-10 expressions (P<0.05). Conclusion Exosome-derived miR-124 promotes the polarization of microglia cells from M1 to M2 and reduces neuroinflammation at acute phase of TBI.
