Markers of Metabolism in Skeletal Muscle and White Adipose Tissue are Distinctly Altered by Differing Dietary Oils in ob/ob Mice

Abstract

Abstract Objectives Investigate the impact of LA-rich oil (LO) on measures of energy metabolism in a mouse model of metabolic syndrome. Methods Ob/ob mice were fed diets containing 6% wt LO, oleic acid-rich (OO) or palmitic acid-rich (PO) for 6 weeks. Body composition was measured at weeks 0 and 6. Plasma was collected at necropsy to measure adiponectin, insulin, and glucose. Grip strength and muscle fiber cross-sectional area (CSA) of total and succinate dehydrogenase-positive (SDH) fibers were quantified in quadriceps. In white adipose tissue, mRNA was measured for markers of beiging and lipid storage. Results Mice fed OO and LO diets (vs. PO diet) had reduced % adipose. There was no difference of oils on plasma adiponectin or HOMA-IR. Decreases in grip strength were observed in PO-fed mice, while OO and LO-fed mice maintained strength throughout the study. LO-fed mice exhibited smaller skeletal muscle fibers compared to the PO-fed mice. OO-fed mice had fewer intermediate-sized SDH fibers. In white adipose tissue, LO-fed mice exhibited increased PGC1a, and decreased PPARy and LPL mRNA compared to PO-fed mice. Conclusions These findings suggest that dietary LA may alter lipid mobilization and metabolism in obese mice. These preliminary results showcase the importance of future investigation of lipid storage and mitochondrial phospholipid biology in skeletal muscle. Funding Sources Funding was provided by NIH R21CA185140, Ohio Agriculture Research and Development Center and the Carol S. Kennedy Professorship. DBS received support from the AOCS Thomas H. Smouse Memorial Fellowship.