GNPAT/USP30 Stabilizes DRP1 Protein to Promote Mitochondrial Fission and Functional Damage in COPD Progression

Area of Science:

• Cell Biology
• Pulmonary Medicine
• Biochemistry

Background:

• Glycerol phosphate O-acyltransferase (GNPAT) has a known role in chronic obstructive pulmonary disease (COPD), but its precise mechanisms are not fully understood.
• Further investigation into GNPAT's function in COPD pathogenesis is crucial for identifying therapeutic targets.

Purpose of the Study:

• To elucidate the molecular mechanisms by which GNPAT regulates COPD.
• To investigate the role of GNPAT, USP30, and DRP1 in mitochondrial dysfunction and apoptosis in COPD models.

Main Methods:

• Cigarette smoke-induced COPD mouse models and A549 cell cultures exposed to cigarette smoke extract (CSE).
• Histological analysis (H&E, immunohistochemistry), cell-based assays (viability, apoptosis, LDH, ATP, ROS), molecular biology techniques (qPCR, Western blotting, co-immunoprecipitation), and electron microscopy.
• Manipulation of gene expression using plasmid transfection and pharmacological inhibition.

Main Results:

• GNPAT and DRP1 were upregulated in COPD models.
• CSE exposure induced mitochondrial fission, dysfunction, and apoptosis, effects exacerbated by a fission inducer.
• GNPAT stabilized DRP1 protein via USP30, leading to increased mitochondrial fission, dysfunction, and apoptosis; inhibition of GNPAT/USP30 reversed these effects.

Conclusions:

• GNPAT recruits USP30 to stabilize DRP1, promoting mitochondrial fission and dysfunction, which contributes to apoptosis in COPD.
• The GNPAT/USP30/DRP1 axis represents a novel pathway in COPD pathogenesis.
• This pathway suggests GNPAT as a potential therapeutic biomarker for COPD.