Metabolic re-patterning in COPD airway smooth muscle cells

Area of Science:

• Cellular metabolism
• Respiratory medicine
• Molecular biology

Background:

• Chronic obstructive pulmonary disease (COPD) is characterized by airway smooth muscle (ASM) thickening, partly due to ASM cell (ASMC) hyperplasia.
• Metabolic reprogramming, including enhanced glycolysis and glutamine breakdown, fuels cellular growth and redox balance.

Purpose of the Study:

• To investigate distinct metabolic phenotypes in COPD ASMCs that may contribute to their increased growth.
• To compare metabolic profiles of ASMCs from healthy non-smokers, healthy smokers, and COPD patients.

Main Methods:

• Exploratory intracellular metabolic profiling of ASMCs.
• Analysis under unstimulated and growth-stimulating conditions (TGF-β and FBS).
• Assessment of metabolic pathways including glycolysis, glutaminolysis, and fatty acid oxidation.

Main Results:

• COPD ASMCs displayed impaired energy balance and accumulated lactate, glutamine, fatty acids, and amino acids.
• Reduced fatty acid oxidation in unstimulated COPD ASMCs was restored upon stimulation.
• Stimulated COPD ASMCs showed increased pentose phosphate pathway activity, nucleotide biosynthesis, and enhanced redox balance (higher GSH/GSSG ratio).

Conclusions:

• Altered glycolysis, glutaminolysis, and fatty acid metabolism contribute to increased biosynthesis and redox balance in COPD ASMCs.
• These metabolic shifts support ASMC hyperplasia in COPD.
• Targeting these metabolic pathways may offer novel therapeutic strategies for COPD.