UCLA

Lipoprotein lipase (LPL) is a key enzyme responsible for the lipolytic processing of triglyceride rich lipoproteins (TRLs), with deficiencies in LPL known to cause familial chylomicronemia and mutations associated with hypertriglyceridemia. Upon synthesis, LPL is secreted into the interstitial spaces where it binds to GPIHBP1, an endothelial cell (EC) GPI-anchored protein. GPIHBP1 facilitates the transport of LPL across the capillary lumen where it functions in the intravascular processing of TRLs. This study leverages single cell RNA sequencing (scRNA-seq) to investigate the cell-type-specific expression of Lpl and Gpihbp1 across tissues. In our study we confirm the presence of known LPL synthesizing cells in mouse cardiac and adipose tissues, validating previous findings, and providing further support for their role in lipid metabolism. Additionally, our investigation highlights a novel observation: the expression of Lpl in the endothelial cells of skeletal muscle tissue. Most notably, these analyses uncover new insights into Lpl and Gpihbp1 expression in the choroid plexus of embryonic mice, unveiling a possible role of LPL-mediated intravascular lipolysis in the central nervous system. Overall, the study provides a comprehensive overview of Lpl expression across tissues known for robust LPL-mediated lipoprotein processing. These findings underscore the importance of understanding tissue- and cell-type-specific gene expression patterns to elucidate the complex regulatory mechanisms underlying lipid metabolism and its implications for human health.