Bariatric surgery improves HDL functionality and reduces inflammation, study suggests
UK: A recent study has shown the beneficial effects of Roux-en-Y gastric bypass (RYGB) on the high-density lipoprotein (HDL) functionality and the reverse cholesterol transport (RCT) among morbidly obese subjects.
The study, published in The Journal of Clinical Endocrinology & Metabolism, found that RYGB improves HDL functionality in association with a reduction in systemic and adipose tissue inflammation.
Emerging evidence has indicated an association between impaired HDL functionality and cardiovascular disease (CVD). HDL is crucial for reverse cholesterol transport and reduces oxidative stress and inflammation via paraoxonase-1 (PON1). RCT is dependent on the capacity of HDL to accept cholesterol (cholesterol efflux capacity [CEC]) and active transport through ATP-binding cassette (ABC) A1, G1, and scavenger receptor-B1 (SR-B1).
Considering the above, Safwaan Adam, The Christie Hospital NHS Foundation Trust, Manchester, United Kingdom, and colleagues investigated the impact of Roux-en-Y gastric bypass in morbidly obese subjects on RCT and HDL functionality.
For this purpose, the researchers measured biomarkers associated with increased CVD risk including high-sensitivity C-reactive protein (hsCRP), tumor necrosis factor-α (TNF-α), PON1 activity, myeloperoxidase mass (MPO), and CEC in vitro. The measurement of these parameters was done in 44 patients before and 6 and 12 months after RYGB.
Overweight but otherwise healthy (mean body mass index [BMI] 28 kg/m2) subjects were taken as controls. Twelve patients also underwent gluteal subcutaneous adipose tissue biopsies before and 6 months after RYGB for targeted gene expression (ABCA1, ABCG1, SR-B1, TNF-α) and histological analysis (adipocyte size, macrophage density, TNF-α immunostaining).
Following were the study's key findings:
- The researchers observed significant improvements in BMI, HDL-cholesterol, hsCRP, TNF-α, MPO mass, PON1 activity, and CEC in vitro after RYGB.
- ABCG1 (fold-change, 2.24) and ABCA1 gene expression increased significantly (fold-change, 1.34).
- Gluteal fat adipocyte size, macrophage density, and TNF-α immunostaining were reduced after RYBG and ABCG1 expression correlated inversely with TNF-α immunostaining.
The researchers conclude, "RYGB enhances HDL functionality in association with a reduction in adipose tissue and systemic inflammation."
Reference:
Safwaan Adam, Jan H Ho, Yifen Liu, Tarza Siahmansur, Kirk Siddals, Zohaib Iqbal, Shazli Azmi, Siba Senapati, John New, Maria Jeziorska, Basil J Ammori, Akheel A Syed, Rachelle Donn, Rayaz A Malik, Paul N Durrington, Handrean Soran, Bariatric Surgery-induced High-density Lipoprotein Functionality Enhancement Is Associated With Reduced Inflammation, The Journal of Clinical Endocrinology & Metabolism, Volume 107, Issue 8, August 2022, Pages 2182–2194, https://doi.org/10.1210/clinem/dgac244
