Endothelial Lipase Is an Alternative Pathway for Fatty Acid Release from Lipoproteins: Evidence from a High Fat Diet Model of Obesity in Rats

BARCHUK MAGALI; MIKSZTOWICZ, VERONICA; ZAGO, VALERIA; CEVEY AGATA; LOPEZ GRACIELA; GOREN NORA; FRIEDMAN, SILVIA; GELPI, RICARDO; CELINA MORALES; FERNANDEZ TOME MARIA DEL CARMEN; SCHREIER , LAURA; BERG, GABRIELA

LIPIDS

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2018

0024-4201

Lipoprotein lipase (LPL) and endothelial lipase(EL) are involved in lipoprotein metabolism. In insulinresistance, their behavior is altered. Peroxisomeproliferator-activated receptors (PPAR) and apoproteins(apo)CII and CIII could be partly responsible for thesealterations. To evaluate Lpl and Lipg, protein levels, andactivity in adipose tissue (AT) and heart in an obesitymodel. Besides, we assessed the role of PPAR and apoC.Male Wistar rats were fed with standard diet (Control,n = 14) or high-fat diet (HFD, n = 14) for 14 weeks. Glucose and lipoprotein profiles were measured. Histologicalstudies were performed in heart and epididymal AT. Lpland Lipg were assessed by reverse transcription polymerasechain reaction (RT-qPCR), protein levels by Western Blot,and activities by radiometric assays. Cardiac and AT PPARexpression were measured by Western Blot and hepaticApoc2 and Apoc3 mRNA by RT-qPCR. In HFD, fatdeposits were observed in hearts, whereas AT presented ahigher adipocyte size. In heart and AT, no differences werefound in Lipg mRNA between groups, while AT LplmRNA and LPL protein were decreased in HFD, withoutdifferences in heart. In both tissues, EL protein levels andactivity were increased and inversely associated withdecreased LPL activity, being partially responsible for theatherogenic lipoprotein profile in HFD. PPARγ expressionin AT was decreased in HFD, without differences in cardiac PPARδ expression and hepatic apoC mRNA. Theincrease in EL activity could be an alternative pathway forfatty acid release from lipoproteins and uptake in tissueswith decreased LPL activity. In AT, PPARγ could beinvolved in enzyme regulation