Astrocytic HILPDA promotes lipid droplets generation to drive cognitive dysfunction in mice with sepsis-associated encephalopathy

Ling Li; Du Lixia; Guifen Gan; Jin Li; Lin Yang; You Wu; Zongping Fang; Xijing Zhang

doi:10.1111/cns.14758

Astrocytic HILPDA promotes lipid droplets generation to drive cognitive dysfunction in mice with sepsis-associated encephalopathy

CNS Neurosci Ther. 2024 May;30(5):e14758. doi: 10.1111/cns.14758.

Authors

Ling Li^{1

2

3}, Du Lixia^{1

2}, Guifen Gan⁴, Jin Li^{1

2}, Lin Yang^{1

2}, You Wu^{1

2}, Zongping Fang^{1

2

5

6}, Xijing Zhang^{1

2}

Affiliations

¹ Department of Critical Care Medicine, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
² Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care Unit, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
³ Department of Pediatric, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
⁴ Department of Critical Care Medicine, Qinghai University Affiliated Hospital, Xining, Qinghai, China.
⁵ Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, China.
⁶ Department of Critical Care Medicine, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, China.

Abstract

Aims: Sepsis-associated encephalopathy (SAE) is manifested as a spectrum of disturbed cerebral function ranging from mild delirium to coma. However, the pathogenesis of SAE has not been clearly elucidated. Astrocytes play important roles in maintaining the function and metabolism of the brain. Most recently, it has been demonstrated that disorders of lipid metabolism, especially lipid droplets (LDs) dyshomeostasis, are involved in a variety of neurodegenerative diseases. The aim of this study was to investigate whether LDs are involved in the underlying mechanism of SAE.

Methods: The open field test, Y-maze test, and contextual fear conditioning test (CFCT) were used to test cognitive function in SAE mice. Lipidomics was utilized to investigate alterations in hippocampal lipid metabolism in SAE mice. Western blotting and immunofluorescence labeling were applied for the observation of related proteins.

Results: In the current study, we found that SAE mice showed severe cognitive dysfunction, including spatial working and contextual memory. Meanwhile, we demonstrated that lipid metabolism was widely dysregulated in the hippocampus by using lipidomic analysis. Furthermore, western blotting and immunofluorescence confirmed that LDs accumulation in hippocampal astrocytes was involved in the pathological process of cognitive dysfunction in SAE mice. We verified that LDs can be inhibited by specifically suppress hypoxia-inducible lipid droplet-associated protein (HILPDA) in astrocytes. Meanwhile, cognitive dysfunction in SAE was ameliorated by reducing A1 astrocyte activation and inhibiting presynaptic membrane transmitter release.

Conclusion: The accumulation of astrocytic lipid droplets plays a crucial role in the pathological process of SAE. HILPDA is an attractive therapeutic target for lipid metabolism regulation and cognitive improvement in septic patients.

Keywords: HILPDA; astrocyte; cognitive dysfunction; lipid droplets; sepsis‐associated encephalopathy.

MeSH terms

Animals
Astrocytes* / metabolism
Cognitive Dysfunction* / etiology
Cognitive Dysfunction* / metabolism
Hippocampus / metabolism
Lipid Droplets* / metabolism
Lipid Metabolism / physiology
Male
Maze Learning / physiology
Mice
Mice, Inbred C57BL*
Sepsis-Associated Encephalopathy* / metabolism

Abstract

MeSH terms

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