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Oxidized LDL upregulates macrophage DPP4 expression via TLR4/TRIF/CD36 pathways.

ABSTRACT: BACKGROUND:We and others have shown that dipeptidyl peptidase-IV (DPP4) expression is increased in obesity/atherosclerosis and is positively correlated with atherosclerotic burden. However, the mechanism by which DPP4 expression is regulated in obesity remains unclear. In this study, we investigated the pathways regulating the expression of DPP4 on macrophages. METHODS:Flowsight® Imaging Flow Cytometry was employed for the detection of DPP4 and immunophenotyping. DPP4 enzymatic activity was measured by a DPPIV-Glo™ Protease Assay kit. FINDINGS:Human monocytes expressed a moderate level of membrane-bound DPP4. Obese patients with body mass index (BMI)???30 had a higher level of monocyte DPP4 expression, in parallel with higher levels of HOMA-IR, blood glucose, triglycerides, and non-HDL cholesterol, compared to those in the non-obese (BMI?

SUBMITTER: Rao X

PROVIDER: S-EPMC6441950 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Oxidized LDL upregulates macrophage DPP4 expression via TLR4/TRIF/CD36 pathways.

Rao Xiaoquan X Zhao Shi S Braunstein Zachary Z Mao Hong H Razavi Michael M Duan Lihua L Wei Yingying Y Toomey Amelia C AC Rajagopalan Sanjay S Zhong Jixin J

EBioMedicine 20190207

<h4>Background</h4>We and others have shown that dipeptidyl peptidase-IV (DPP4) expression is increased in obesity/atherosclerosis and is positively correlated with atherosclerotic burden. However, the mechanism by which DPP4 expression is regulated in obesity remains unclear. In this study, we investigated the pathways regulating the expression of DPP4 on macrophages.<h4>Methods</h4>Flowsight® Imaging Flow Cytometry was employed for the detection of DPP4 and immunophenotyping. DPP4 enzymatic ac ...[more]

PMID: 30738832

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