CD40L contributes to angiotensin II-induced pro-thrombotic state, vascular inflammation, oxidative stress and endothelial dysfunction.
CD40 ligand (CD40L) is involved in the vascular infiltration of immune cells and pathogenesis of atherosclerosis. Additionally, T cell CD40L release causes platelet, dendritic cell and monocyte activation in thrombosis. However, the role of CD40L in angiotensin II (ATII)-driven vascular dysfunction and hypertension remains incompletely understood. We tested the hypothesis that CD40L contributes to ATII-driven vascular inflammation by promoting platelet-leukocyte activation, vascular infiltration of immune cells and by amplifying oxidative stress. C57BL/6 and CD40L-/- mice were infused with ATII (1 mg/kg/day for 7 days) using osmotic minipumps. Vascular function was recorded by isometric tension studies, and reactive oxygen species (ROS) were monitored in blood and heart by optical methods. Western blot, immunohistochemistry, FACS analysis and real-time RT-PCR were used to analyze immune cell distribution, pro-inflammatory cytokines, NAPDH oxidase subunits, T cell transcription factors and other genes of interest. ATII-treated CD40L-/- mice showed improved endothelial function, suppression of blood platelet-monocyte interaction (FACS), platelet thrombin generation (calibrated automated thrombography) and coagulation (bleeding time), as well as decreased oxidative stress in the aorta, heart and blood compared to wild-type mice. Moreover, ATII-treated CD40L-/- mice displayed decreased levels of TH1 cytokines released by splenic CD4⁺ T cells (ELISA) and lower expression levels of NOX-2, T-bet and P-selectin as well as diminished immune cell infiltration in aortic tissue compared to controls. Our results demonstrate that many ATII-induced effects on vascular dysfunction, such as vascular inflammation, oxidative stress and a pro-thrombotic state, are mediated at least in part via CD40L.
II. Medizinische Klinik, Department of Cardiology, Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Langenbeckstr. 1, 55131, Mainz, Germany.
Michael
M
Hausding
Kerstin
K
Jurk
Steffen
S
Daub
Swenja
S
Kröller-Schön
Judith
J
Stein
Melanie
M
Schwenk
Matthias
M
Oelze
Yuliya
Y
Mikhed
Jasmin Ghaemi
JG
Kerahrodi
Sabine
S
Kossmann
Thomas
T
Jansen
Eberhard
E
Schulz
Philip
P
Wenzel
Angelika B
AB
Reske-Kunz
Christian
C
Becker
Thomas
T
Münzel
Stephan
S
Grabbe
Andreas
A
Daiber
D000804:Angiotensin II / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D015153:Blotting, Western; D023201:CD40 Ligand / Q000378:metabolism*; D042783:Endothelial Cells / Q000378:metabolism* / Q000473:pathology; D005434:Flow Cytometry; D007150:Immunohistochemistry; D007249:Inflammation / Q000378:metabolism; D007962:Leukocytes; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018384:Oxidative Stress / Q000502:physiology*; D015539:Platelet Activation / Q000502:physiology; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013927:Thrombosis / Q000378:metabolism; D014652:Vascular Diseases / Q000276:immunology / Q000378:metabolism
D000804:Angiotensin II; D023201:CD40 Ligand