Comparative Phosphoproteomic Analysis Demonstrates That AMPKα2 Knockout Exacerbates Hepatic Aging in Mice

Area of Science:

• Gerontology
• Metabolic Regulation
• Molecular Biology

Background:

• Aging is linked to metabolic dysregulation, particularly in the liver.
• AMP-activated protein kinase α2 (AMPKα2) is crucial for energy metabolism.
• The impact of germline AMPKα2 knockout on aged liver phosphoproteins remains understudied.

Purpose of the Study:

• To investigate the effects of germline AMPKα2 knockout on aged mouse liver.
• To analyze morphological changes, protein phosphorylation, and senescence phenotypes.
• To identify molecular signatures associated with exacerbated hepatic aging.

Main Methods:

• Morphological analysis of liver tissues.
• Western blot (WB) for protein validation and senescence markers.
• Data-independent acquisition (DIA) phosphoproteomics to profile phosphopeptides.

Main Results:

• AMPKα2 knockout exacerbated glucose-lipid metabolism dysfunction, inflammation, and senescence.
• Phosphoproteomics identified 316 differentially modified phosphopeptides, including enhanced phosphorylation of Acaca and HSP90β.
• Reduced phosphorylation of stress response protein HSP27 was observed and validated by WB.

Conclusions:

• AMPKα2 knockout significantly worsens hepatic aging and metabolic dysfunction.
• Novel molecular signatures of AMPKα2 knockout in aged liver were identified.
• HSP27 phosphorylation may be a downstream effect of AMPKα2, offering potential therapeutic targets for age-related liver diseases.