Solidification of Lipid Droplets Aid the Onset of Obesity in Mice on Calorie-Dense Diets

Speaker

Cecilia Leal

Professor, Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign

About This Talk

Adipose-derived lipid droplets (LDs) are rich in triacylglycerols (TAGs), which regulate essential cellular processes such as energy storage. Although TAG accumulation and LD expansion in adipocytes occur during obesity, how LDs dynamically package TAGs in response to excessive nutrients remains elusive. We will present our recent findings that LD lipidomes display a remarkable increase in TAG acyl chain saturation under calorie-dense diets, turning them conducive to close-packing. Using traditional materials’ characterization techniques such as X-ray diffraction, solid-state NMR, and high-resolution imaging, we show that beyond size, LDs derived from mice under obesogenic diets govern fat accumulation by packing TAGs in different crystalline polymorphs. Consistently, LDs and tissue stiffen for high-calorie-fed mice with more than a two-fold increase in elastic moduli compared to normal diet. Our data suggest that LDs undergo structural remodeling, close–packing rigid and highly saturated TAGs in response to caloric overload, allowing for optimal expansion of fat during the initial stages of obesity. 

Biography

Cecilia Leal is a Professor of Materials Science and Engineering at the University of Illinois at Urbana-Champaign (UIUC) since 2012. Her lab investigates lipids, soft, and often living materials for which she has received numerous awards such as the 2016 NIH Director’s New Innovator and NSF CAREER Awards. Cecilia is often in the list of excellent teachers ranked by her students and received the 2022 College Award for Sustained Excellence in Diversity, Equity, and Inclusion.