Linoleate-rich safflower oil diet increases linoleate-derived bioactive lipid mediators in plasma, and brown and white adipose depots of healthy mice

Authors: SNOKE, DEENA - The Ohio State University; ANGELOTTI, AUSTIN - The Ohio State University; BORKOWSKI, KAMIL - University Of California, Davis; COLE, RACHEL - The Ohio State University; Newman, John; BELURY, MARTHA - The Ohio State University

Submitted to: Metabolites
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/8/2022
Publication Date: 8/12/2022
Citation: Snoke, D., Angelotti, A., Borkowski, K., Cole, R., Newman, J.W., Belury, M.A. 2022. Linoleate-rich safflower oil diet increases linoleate-derived bioactive lipid mediators in plasma, and brown and white adipose depots of healthy mice. Metabolites. 12(8). Article 743. https://doi.org/10.3390/metabo12080743.
DOI: https://doi.org/10.3390/metabo12080743

Interpretive Summary: Polyunsaturated fats are both an important energy source and starting materials the body uses to produce compounds call lipid mediators that regulate a variety of processes, including cell growth, inflammation, and energy metabolism. Adipose tissues store energy as fat, but also influences the bodies energy metabolism by the secretion of a variety of active substances. How diet influences lipid mediator levels in adipose tissues my therefore have broad impacts on energy metabolism. While white adipose tissue is primarily a storage and secretory tissue, brown adipose tissue is metabolically active, actively burning fat to generate heat. Brown adipose is a very small proportion of the fatty and its importance role and importance in energy metabolism not well understood today. To determine how dietary lipid sources modulate both brown and white adipose tissue, as well as plasma lipid mediators, mice were fed very low-fat (i.e. 15% caloric fat) isocaloric diets either rich in saturated and monounsaturated fats, or rich in polyunsaturated fats. Before and after 5 weeks of feeding, body weight, adiposity and fasting blood glucose were measured and lipid mediators were profiled in plasma, inguinal white and interscapular brown adipose tissues. We identified changes to lipid mediators with known to regulate adipose tissue growth and found strong relationships between the magnitude of diet-induced lipid mediator changes in adipose tissue and plasma. Our findings emphasize that even in a low-fat diet, dietary fat quality has a profound effect on lipid mediator profiles in adipose tissues and plasma.

Technical Abstract: Polyunsaturated fats are energy substrates and precursors to the biosynthesis of lipid mediators of cellular processes. Adipose tissue not only provides energy storage but influences whole-body energy metabolism through endocrine functions. How diet influences adipose lipid mediator balances may have broad impacts on energy metabolism. To determine how dietary lipid sources modulate brown and white adipose tissue and plasma lipid mediators, mice were fed low-fat (15%kcal fat) isocaloric diets, containing either palm oil (POLF) or linoleate-rich safflower oil (SOLF). Baseline and post body weight, adiposity and fasting blood glucose were measured and lipid mediators were profiled in plasma, inguinal white and interscapular brown adipose tissues. We identified over species of lipid mediators altered between diets and found that these changes were unique to each tissue. We identified changes to lipid mediators with known functional roles in the regulation of adipose tissue expansion and function and found that there was a relationship between the average fold difference in lipid mediators between brown adipose tissue and plasma in mice consuming the SOLF diet. Our findings emphasize that even in a low-fat diet, dietary fat quality has a profound effect on lipid mediator profiles in adipose tissues and plasma.