Thrombospondin-1 (TSP1) contributes to the development of vascular inflammation by regulating monocytic cell motility in mouse models of abdominal aortic aneurysm.

PubMed ID: 25940549

Author(s): Liu Z, Morgan S, Ren J, Wang Q, Annis DS, Mosher DF, Zhang J, Sorenson CM, Sheibani N, Liu B. Thrombospondin-1 (TSP1) contributes to the development of vascular inflammation by regulating monocytic cell motility in mouse models of abdominal aortic aneurysm. Circ Res. 2015 Jul 3;117(2):129-41. doi: 10.1161/CIRCRESAHA.117.305262. Epub 2015 May 4. Erratum in: Circ Res. 2015 Aug 14;117(5):e55. PMID 25940549

Journal: Circulation Research, Volume 117, Issue 2, Jul 2015

RATIONALE Histological examination of abdominal aortic aneurysm (AAA) tissues demonstrates extracellular matrix destruction and infiltration of inflammatory cells. Previous work with mouse models of AAA has shown that anti-inflammatory strategies can effectively attenuate aneurysm formation. Thrombospondin-1 is a matricellular protein involved in the maintenance of vascular structure and homeostasis through the regulation of biological functions, such as cell proliferation, apoptosis, and adhesion. Expression levels of thrombospondin-1 correlate with vascular disease conditions.

OBJECTIVE To use thrombospondin-1-deficient (Thbs1(-/-)) mice to test the hypothesis that thrombospondin-1 contributes to pathogenesis of AAAs.

METHODS AND RESULTS Mouse experimental AAA was induced through perivascular treatment with calcium phosphate, intraluminal perfusion with porcine elastase, or systemic administration of angiotensin II. Induction of AAA increased thrombospondin-1 expression in aortas of C57BL/6 or apoE-/- mice. Compared with Thbs1(+/+) mice, Thbs1(-/-) mice developed significantly smaller aortic expansion when subjected to AAA inductions, which was associated with diminished infiltration of macrophages. Thbs1(-/-) monocytic cells had reduced adhesion and migratory capacity in vitro compared with wild-type counterparts. Adoptive transfer of Thbs1(+/+) monocytic cells or bone marrow reconstitution rescued aneurysm development in Thbs1(-/-) mice.

CONCLUSIONS Thrombospondin-1 expression plays a significant role in regulation of migration and adhesion of mononuclear cells, contributing to vascular inflammation during AAA development.

© 2015 American Heart Association, Inc.