The bronchoalveolar proteome changes in obesity.

Area of Science:

• Pulmonary Medicine
• Biochemistry
• Proteomics

Background:

• Obesity is linked to systemic inflammation and metabolic changes.
• The impact of obesity on lung biochemistry in humans without lung disease is not well understood.
• Altered lung biochemistry may contribute to pulmonary dysfunction in obesity.

Purpose of the Study:

• To investigate the proteomic composition of bronchoalveolar lavage fluid (BALF) in relation to body mass index (BMI).
• To identify specific proteins and pathways in the lungs that are altered by obesity.
• To explore potential biochemical mechanisms linking obesity to pulmonary dysfunction.

Main Methods:

• Collected BALF from 14 adults with a wide range of BMIs and no lung disease.
• Utilized sequential window acquisition of all theoretical fragment ion spectra (SWATH) mass spectrometry to analyze proteomes.
• Examined proteomic composition and pathway enrichments as a function of BMI.

Main Results:

• Identified five proteins strongly correlated with BMI, including acute phase reactants and complement factors.
• Found pathway enrichments impacted by BMI related to innate immunity, oxidative stress, and lipid metabolism.
• Observed minimal differences in BALF proteomes between lavage regions and between sexes.

Conclusions:

• Obesity alters the bronchoalveolar microenvironment in humans, even without pre-existing lung disease.
• BMI-associated pathway alterations include those involved in coagulation, oxidative stress, energy metabolism, and immune function.
• These findings suggest conserved biochemical changes in obesity may underlie pulmonary dysfunction.