Lipidomics reveals AMI-induced brown adipose tissue lipid remodeling linked to serum lipid changes in mice.

Accumulated evidence suggests that brown adipose tissue (BAT) has potential benefits for promoting cardiometabolic health. However, the underlying mechanism by which BAT affects acute myocardial infarction (AMI) remains unclear. In this study, we optimized the lipidomics data acquisition mode and lipid extraction protocol of serum and BAT based on the UPLC-HRMS platform, and applied it to the analysis of AMI mice. The result showed that targeted data-dependent acquisition based on the inclusion list of differential and preidentified ions (dpDDA) mode has broader characteristic ion coverage, better stability, and higher quality MS/MS spectra compared with the data-independent acquisition (DIA) and data-dependent acquisition (DDA). The isopropanol (IPA) extraction protocol obtained more lipids and provided a higher response for BAT and serum lipids. Based on the above verification method, AMI mice were analyzed by the screening criteria of the Student's t-test (p < 0.05, VIP >1), 80 and 100 lipids (the main types were fatty acids and glycerophospholipids) were identified in serum and BAT, respectively. Further correlation analysis found that fatty acids are the most important lipids affected in serum and BAT, these fatty acids have been previously implicated closely associated with the thermogenic function of BAT and vascular function, suggesting a potential mechanism by which BAT may influence cardiac vascular function. In summary, the established lipidomics method can achieve high coverage, high stability, and high-quality collection of BAT and serum lipids, which can provide new insights into the physiological mechanism of BAT that regulates lipid metabolism and affects AMI.