P141 Telomere Dynamics Relation with Obesity

Background The relation between telomere dynamics and obesity remains unclear. Cross-sectional studies found associations between short leukocyte telomere length (LTL) and high body mass index (BMI) but longitudinal studies did not find any association between LTL attrition and BMI. In two parallel studies, we aimed to assess the relationship between obesity and telomere dynamics in different tissues. Methods Study 1: Measurements of LTL and TL in skeletal muscle (MTL) were performed in 53 subjects with severe obesity (BMI > 35) and in 53 age- and sex-matched without obesity (21 < BMI < 30). MTL is a proxy of TL at birth and the LTL/MTL ratio represents life-long telomere attrition. Study 2: Measurements of TL in subcutaneous fat (SCF), a high proliferative adipose tissue, and visceral fat (VF), a low proliferative one in 50 severe obese bariatric patients. TL measurements were performed by Southern blot. Results Study 1: In younger (<55 years), but not in older, LTL and LTL/MTL were shorter in obese patients vs controls (7.16 kb vs 7.54 kb, p < 0.05 for LTL and 81% vs 84%, p < 0.05 for LTL/MTL). Study 2: Within obese bariatric patients, SCF/VF TL ratio was lower in those with early onset obesity (96% for obesity since childhood vs 97% since adolescence vs 100% for adult development of obesity; p < 0.05). Conclusions Early life obesity is associated with higher TL attrition leading to shorter TL in high proliferative tissues.