Bariatric surgery, initiates "substantial weight loss and improves lung function, according to researchers from the University of Vermont. Researchers also found post-surgery plasma collected from volunteers showed a reduced inflammatory response from cells that line the airways compared to pre-surgery plasma. The findings of this study align with previous literature, which also show the benefits of bariatric surgery such as weight loss and improved lung function.
"Our findings suggest that while weight loss is beneficial, fat-derived factors may not be the main contributors that affect obese asthma," said Dr Paola E Peña García, a PhD candidate and lead author of the study.
For this study, researchers were focused on understanding the mechanisms behind these improvements in hopes of developing new treatments for obese asthma. In addition, methods possibly mimicking the benefits of weight loss, including exercise and diet changes, may also lead to new therapeutics. The research team set out to learn how obesity and weight loss affect the airway as it relates to asthma. The investigation method consisted of using cells that line the airways and control airway narrowing.
Researchers used the results to examine the effects of circulating fat-derived factors from asthmatic and non-asthmatic obese patients undergoing bariatric surgery. Scientists collected data on lung function, body mass index and self-reported asthma management. Fat tissue was collected during bariatric surgery. Plasma samples were collected before and at various stages after bariatric surgery.
They found that weight loss following bariatric surgery decreases the capacity for plasma to augment proinflammatory cytokine secretion by human bronchial epithelial cells, implicating that circulating but not adipocyte-derived factors are important modulators in obese asthma.
“To the best of our knowledge, this study is the first to address the gap in understanding the effects of circulating and adipocyte-derived factors through exposure to adipocyte-conditioned media (Ad-CM) on relevant cellular drivers in asthma by utilising samples from an ongoing longitudinal study following a cohort of asthmatic and non-asthmatic obese subjects over the course of 12 months after undergoing bariatric surgery,” the researchers concluded. “The data presented show clear evidence that weight loss directly and beneficially impacts lung airway responses; however, the exact mechanism through which this works is still unknown.”
Researchers conceded that more studies are needed to fully understand how obesity and weight loss affect asthma treatment.
The findings were featured in the paper, ‘Bariatric surgery decreases the capacity of plasma from obese asthmatic subjects to augment airway epithelial cell proinflammatory cytokine production’, published in the American Journal of Physiology-Lung Cellular and Molecular Physiology. To access this paper, please click here