GSDMD gene knockout alleviates hyperoxia-induced hippocampal brain injury in neonatal mice

© 2023. BioMed Central Ltd., part of Springer Nature..

BACKGROUND: Neonatal hyperoxia exposure is associated with brain injury and poor neurodevelopment outcomes in preterm infants. Our previous studies in neonatal rodent models have shown that hyperoxia stimulates the brain's inflammasome pathway, leading to the activation of gasdermin D (GSDMD), a key executor of pyroptotic inflammatory cell death. Moreover, we found pharmacological inhibition of caspase-1, which blocks GSDMD activation, attenuates hyperoxia-induced brain injury in neonatal mice. We hypothesized that GSDMD plays a pathogenic role in hyperoxia-induced neonatal brain injury and that GSDMD gene knockout (KO) will alleviate hyperoxia-induced brain injury.

METHODS: Newborn GSDMD knockout mice and their wildtype (WT) littermates were randomized within 24 h after birth to be exposed to room air or hyperoxia (85% O2) from postnatal days 1 to 14. Hippocampal brain inflammatory injury was assessed in brain sections by immunohistology for allograft inflammatory factor 1 (AIF1) and CD68, markers of microglial activation. Cell proliferation was evaluated by Ki-67 staining, and cell death was determined by TUNEL assay. RNA sequencing of the hippocampus was performed to identify the transcriptional effects of hyperoxia and GSDMD-KO, and qRT-PCR was performed to confirm some of the significantly regulated genes.

RESULTS: Hyperoxia-exposed WT mice had increased microglia consistent with activation, which was associated with decreased cell proliferation and increased cell death in the hippocampal area. Conversely, hyperoxia-exposed GSDMD-KO mice exhibited considerable resistance to hyperoxia as O2 exposure did not increase AIF1 + , CD68 + , or TUNEL + cell numbers or decrease cell proliferation. Hyperoxia exposure differentially regulated 258 genes in WT and only 16 in GSDMD-KO mice compared to room air-exposed WT and GSDMD-KO, respectively. Gene set enrichment analysis showed that in the WT brain, hyperoxia differentially regulated genes associated with neuronal and vascular development and differentiation, axonogenesis, glial cell differentiation, hypoxia-induced factor 1 pathway, and neuronal growth factor pathways. These changes were prevented by GSDMD-KO.

CONCLUSIONS: GSDMD-KO alleviates hyperoxia-induced inflammatory injury, cell survival and death, and alterations of transcriptional gene expression of pathways involved in neuronal growth, development, and differentiation in the hippocampus of neonatal mice. This suggests that GSDMD plays a pathogenic role in preterm brain injury, and targeting GSDMD may be beneficial in preventing and treating brain injury and poor neurodevelopmental outcomes in preterm infants.

Errataetall:

UpdateOf: Res Sq. 2023 Jun 15;:. - PMID 37398125

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:20

Enthalten in:

Journal of neuroinflammation - 20(2023), 1 vom: 07. Sept., Seite 205

Sprache:

Englisch

Beteiligte Personen:

Challa, Naga Venkata Divya [VerfasserIn]
Chen, Shaoyi [VerfasserIn]
Yuan, Huijun [VerfasserIn]
Duncan, Matthew R [VerfasserIn]
Moreno, William Javier [VerfasserIn]
Bramlett, Helen [VerfasserIn]
Dietrich, W Dalton [VerfasserIn]
Benny, Merline [VerfasserIn]
Schmidt, Augusto F [VerfasserIn]
Young, Karen [VerfasserIn]
Wu, Shu [VerfasserIn]

Links:

Volltext

Themen:

Brain injury
GSDMD knockout
GSDMD protein, human
Gene transcription
Gsdmd protein, mouse
Journal Article
Microglial
Neonatal
Phosphate-Binding Proteins
Pore Forming Cytotoxic Proteins
Pyroptosis

Anmerkungen:

Date Completed 14.09.2023

Date Revised 10.04.2024

published: Electronic

UpdateOf: Res Sq. 2023 Jun 15;:. - PMID 37398125

Citation Status MEDLINE

doi:

10.1186/s12974-023-02878-8

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM36177365X