Fatty Acid Binding Protein 4 Promotes Microglia-induced Inflammatory Response After Traumatic Brain Injury
10.3870/j.issn.1672-0741.24.10.015
- VernacularTitle:脂肪酸结合蛋白4促进创伤性脑损伤后小胶质细胞诱导的炎症反应
- Author:
Xiaoya ZHANG
1
;
Kunpeng WANG
;
Shuang LI
Author Information
1. 河南省南阳市中心医院磁共振影像诊断科,南阳 473000
- Publication Type:Journal Article
- Keywords:
fatty acid binding protein 4;
traumatic brain injury;
microglia;
inflammatory response;
mitochondrial ROS;
NLRP3 inflammasome
- From:
Acta Medicinae Universitatis Scientiae et Technologiae Huazhong
2025;54(2):180-189
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the mechanism by which fatty acid-binding protein 4(Fabp4)regulates neuroinflamma-tion after traumatic brain injury(TBI).Methods Adult wild-type C57 male mice were randomly divided into sham group and TBI group,with 6 mice in each group.Fabp4 knockout(Fabp4-/-)male mice were randomly divided into sham group and TBI group,with 6 mice in each group.Western blot was used to detect the expression levels of Fabp4,IL-1β,TNF-α,NLRP3,Caspase-1,and ASC proteins in brain tissue from each group.Brain water content was assessed using the wet-to-dry weight method,and neuronal damage was evaluated by Nissl staining.Immunofluorescence double staining was performed to detect the expression of microglial M1 polarization markers(CD86 and iNOS),M2 polarization marker(CD206),and astrocytic polarization marker(C3).Enzyme-linked immunosorbent assay(ELISA)was used to measure the levels of pro-inflammatory factors IL-1βand TNF-α in the culture supernatant of BV2 cells.MitoSOX red fluorescence staining was used to assess mitochondrial ROS levels in BV2 cells,and ELISA was employed to determine the levels of malondialdehyde(MDA)and 8-hydroxy-2'-deox-yguanosine(8-OHdG)in brain tissue after TBI.Immunofluorescence was performed to detect NLRP3 protein expression in BV2 cells.Results In wild-type mice,the expression of Fabp4 protein in the injured brain region was significantly increased at 12 hours post-TBI compared to the sham group(P＜0.01)and peaked at 3 days post-injury(P＜0.01).Compared to the wild-type TBI group,protein expression levels of IL-1β and TNF-α were reduced(P＜0.01),and brain water content was decreased(P＜0.05)in Fabp4-/-mice from TBI group.Nissl staining revealed that the volume of brain damage following TBI was reduced af-ter Fabp4 deletion(P＜0.05).Immunofluorescence experiments showed that M1 polarization of microglia was inhibited after Fabp4 deletion(P＜0.01),and M2 polarization was promoted(P＜0.01).Fabp4 deletion had no significant effect on astrocytic polarization.BV2 cell experiments demonstrated that the levels of IL-1β and TNF-α in the culture supernatant were increased(P＜0.01)after Fabp4 overexpression,and mitochondrial ROS production was elevated(P＜0.01).After LPS stimulation,Fabp4 protein expression in BV2 cells was increased(P＜0.01),the levels of IL-1β and TNF-α(P＜0.05)as well as mitochondrial ROS(P＜0.01)were reduced after BMS309403 intervention.In the mouse model,the levels of MDA and 8-OHdG in the brain tissue of Fabp4-/-TBI mice were significantly lower than those of wild-type TBI mice(P＜0.01).The levels of NLRP3,ASC,and Caspase-1 proteins in BV2 cells were increased after Fabp4 overexpression(P＜0.01),while ROS scavenger treatment reversed this effect(P＜0.01,P＜0.05,P＜0.01).In the mouse model,the levels of NLRP3,ASC,and Caspase-1 proteins in Fabp4-/-TBI mice were significantly lower than those in wild-type TBI mice(P＜0.01,P＜0.05,P＜0.01).Conclusion Fabp4 pro-motes microglia-induced neuroinflammation after TBI by regulating mitochondrial ROS production and NLRP3 inflammasome formation.These findings suggest that Fabp4 may serve as a potential therapeutic target for TBI.
