Dataset Information

Endothelial cells microparticle-associated protein disulfide isomerase promotes platelet activation in metabolic syndrome.

ABSTRACT:

Background

Metabolic syndrome (MetS) is a common challenge in the world, and the platelet activation is enhanced in MetS patients. However, the fundamental mechanism that underlies platelet activation in MetS remains incompletely understood. Endothelial cells are damaged seriously in MetS patients, then they release more endothelial microparticles (EMPs). After all, whether the EMPs participate in platelet activation is still obscure. If they were, how did they work?

Results

We demonstrated that the levels of EMPs, PMPs (platelet derived microparticles) and microparticle-carried-PDI activity increased in MetS patients. IR endothelial cells released more EMPs, the EMP-PDI was more activated. EMPs can enhance the activation of CD62P, GPIIb/IIIa and platelet aggregation and this process can be partly inhibited by PDI inhibitor such as RL90 and rutin. Activated platelets stimulated by EMPs expressed more PDI on cytoplasm and released more PMPs.

Materials and methods

We obtained plasma from 23 MetS patients and 8 normal healthy controls. First we built insulin resistance (IR) model of human umbilical vein endothelial cells (HUVECs), and then we separated EMPs from HUVECs culture medium and used these EMPs to stimulate platelets. Levels of microparticles, P-selectin(CD62P), Glycoprotein IIb/IIIa (GPIIb/IIIa) were detected by flow cytometry and levels of EMPs were detected by enzyme-linked immunosorbent assay (ELISA). The protein disulfide isomerase (PDI) activity was detected by insulin transhydrogenase assay. Platelet aggregation was assessed by turbidimetry.

Conclusion

EMPs can promote the activation of GPIIb/IIIa in platelets and platelet aggregation by the PDI which is carried on the surface of EMPs.

SUBMITTER: Fan GQ

PROVIDER: S-EPMC5347765 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Publications

Endothelial cells microparticle-associated protein disulfide isomerase promotes platelet activation in metabolic syndrome.

Fan Guan-Qi GQ Qin Ran-Ran RR Li Yi-Hui YH Song Dai-Jun DJ Chen Tong-Shuai TS Zhang Wei W Zhong Ming M Zhang Yun Y Xing Yan-Qiu YQ Wang Zhi-Hao ZH

Oncotarget 20161201 50

<h4>Background</h4>Metabolic syndrome (MetS) is a common challenge in the world, and the platelet activation is enhanced in MetS patients. However, the fundamental mechanism that underlies platelet activation in MetS remains incompletely understood. Endothelial cells are damaged seriously in MetS patients, then they release more endothelial microparticles (EMPs). After all, whether the EMPs participate in platelet activation is still obscure. If they were, how did they work?<h4>Results</h4>We de ...[more]

PMID: 27825126

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Dataset Information

Endothelial cells microparticle-associated protein disulfide isomerase promotes platelet activation in metabolic syndrome.

Background

Results

Materials and methods

Conclusion

Publications

Endothelial cells microparticle-associated protein disulfide isomerase promotes platelet activation in metabolic syndrome.

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