Abstract P184: Association of Plasma Lipid Species With Lipoprotein Insulin Resistance Score Before and After Exercise Training

Background: The lipoprotein insulin resistance (LP-IR) score has been shown to assess insulin resistance, predict future type 2 diabetes, and improve with regular exercise. The lipidomic profile is known to differ with insulin resistance and type 2 diabetes, but few studies have examined lipidome associations with LP-IR, particularly in response to an exercise intervention. Methods: Plasma lipids were measured using the C8-positive LC-MS method in 671 participants from the HERITAGE Family Study (56% Female, 35% Black, 35.2 yrs) before and after a 20-week exercise intervention. LP-IR, a weighted index of six lipoprotein parameters, was measured before and after training through nuclear magnetic resonance spectroscopy (Labcorp, NC). Linear mixed models were used to test the associations of 193 known plasma lipids with LP-IR before and after exercise training. All models were adjusted for age, sex, and race, while post-training models also adjusted for baseline lipid and baseline LP-IR. Results: A total of 162 lipids (84%) were associated (FDR<0.05) with LP-IR at baseline ( Figure 1 ). The top positive associations were found for TG species, while cholesterol ester species showed the top inverse associations. Following training, the change in 143 (74%) lipids were associated (FDR<0.05) with change in LP-IR. There were 129 lipid species associated with both baseline and changes in LP-IR, while 33 were only associated with baseline measures and 14 only associated with changes in LP-IR following exercise ( Figure 1 ). Conclusions: We found that most lipids were associated with LP-IR regardless of exercise training status. Importantly, we identified a subset of lipids that were only associated with changes in LP-IR, which may represent exercise responsive biomarkers of exercise induced changes in LP-IR. However, further research is needed to identify the biological mechanisms connecting the changes in these lipid species and metabolic changes following exercise training.