Role of Drp1 in A1 activation of astrocytes
10.3969/j.issn.1000-4718.2025.01.008
- VernacularTitle:Drp1在星形胶质细胞A1型活化中的作用
- Author:
Longyun ZHOU
1
;
Xuqing CHEN
;
Lu FANG
;
Min YAO
;
Shufen LIU
Author Information
1. 南京医科大学第一附属医院,江苏 南京 210029
- Publication Type:Journal Article
- Keywords:
dynamin-related protein 1;
mitochondrial fission;
astrocytes;
A1 activation
- From:
Chinese Journal of Pathophysiology
2025;41(1):64-71
- CountryChina
- Language:Chinese
-
Abstract:
AIM:This study aims to investigate the role of dynamin-related protein 1(Drp1)in the A1 type activation of astrocytes and elucidate the underlying mechanism of abnormal astrocyte activation.METHODS:Rat astro-cyte line CTX-TNA2 was divided into control group,astrocyte-conditioned medium(ACM)group,and 5,10 and 25 μmol/L mitochondrial division inhibitor-1(Mdivi-1;a selective inhibitor of Drp1)+ACM group.The cells in ACM group were exposed to ACM containing interleukin-1α(IL-1α),tumor necrosis factor-α(TNF-α)and complement 1q(C1q)for 24 h to induce type A1 activation,while those in Mdivi-1+ACM group were pre-treated with various concentrations of Mdi-vi-1 for 2 h before stimulation with ACM for 24 h.RT-qPCR was used to detect the expression levels of A1 type activation-related indicators IL-1β,TNF-α and IL-10 mRNA in each group.Immunofluorescence was utilized to assess the expres-sion levels of A1 type activation marker molecules C3,inducible nitric oxide synthase(iNOS)and S100 calcium binding protein A10(S100A10).The level of mitochondrial reactive oxygen species(ROS)was measured using MitoSOX Red staining and flow cytometry analysis.The mitochondrial morphology was observed using the MICA full-field imaging analy-sis platform.Lastly,the expression level of mitochondrial fission protein 1(FIS1)and the activation level of Drp1 in each group were evaluated through immunoblotting analysis.RESULTS:The RT-qPCR and immunofluorescence results indi-cated that the ACM group exhibited significantly elevated levels of IL-1β and TNF-α mRNA,and C3 protein expression compared with control group,along with increased iNOS protein expression and reduced IL-10 mRNA and S100A10 pro-tein expression(P＜0.05).Interventions with 10 and 25 μmol/L Mdivi-1 effectively inhibited the rise in IL-1β and TNF-α mRNA,and C3 and iNOS protein expression induced by ACM,while promoting S100A10 expression.MitoSOX Red staining revealed a significant increase in mitochondrial ROS levels in astrocytes stimulated by ACM,which was effectively re-versed by Mdivi-1 intervention.The MICA full-field imaging analysis platform demonstrated that ACM induced the forma-tion of round-shaped mitochondria in astrocytes,while 10 and 25 μmol/L Mdivi-1 interventions facilitated the restoration of their tubular shape.Additionally,Western blot results confirmed that Mdivi-1 intervention effectively reversed the acti-vation of Drp1 and FIS1.CONCLUSION:The Drp1-mediated mitochondrial fission represents one of the intrinsic molecu-lar mechanisms underlying A1 type activation of astrocytes,and Mdivi-1,as a selective inhibitor of Drp1,can effectively inhibit abnormal astrocyte activation.
