Doxycycline alters vascular smooth muscle cell adhesion, migration, and reorganization of fibrillar collagen matrices.
Remodeling of injured blood vessels is dependent on smooth muscle cells and matrix metalloproteinase activity. Doxycycline is a broad spectrum matrix metalloproteinase inhibitor that is under investigation for the treatment of acute coronary syndromes and aneurysms. In the present study, we examine the mechanisms by which doxycycline inhibits smooth muscle cell responses using a series of in vitro assays that mimic critical steps in pathological vascular remodeling. Doxycycline treatment dramatically increased smooth muscle cell adhesion to the substrate, as evidenced by interference reflection microscopy and immunostaining for paxillin and phosphotyrosine. Cell aggregation was also potentiated after treatment with doxycycline. Treatment with 104 mumol/L doxycycline reduced thymidine uptake by 58% compared with untreated cells (P < 0.05) and inhibited closure of a scrape wound made in a smooth muscle cell monolayer by 20% (P < 0.05). Contraction of a three-dimensional collagen gel was used as an in vitro model for constrictive vessel remodeling, demonstrating that treatment with 416 mumol/L doxycycline for 12 hours inhibited collagen gel remodeling by 37% relative to control (P < 0.05). In conclusion, we have shown that doxycycline treatment leads to dramatically increased smooth muscle cell adhesion, which in turn might limit responses in pathological vascular remodeling.
Franco
Christopher
C
Department of Laboratory Medicine and Pathobiology, University of Toronto, ON, Canada M5S 1A8.
Ho
Bernard
B
Mulholland
Diane
D
Hou
Guangpei
G
Islam
Muzharul
M
Donaldson
Katey
K
Bendeck
Michelle Patricia
MP
D000199:Actins / Q000378:metabolism; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects*; D002465:Cell Movement / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004318:Doxycycline / Q000494:pharmacology*; D024022:Fibrillar Collagens / Q000378:metabolism*; D008297:Male; D009131:Muscle, Smooth, Vascular; D032389:Myocytes, Smooth Muscle / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D000199:Actins; D024022:Fibrillar Collagens; D004318:Doxycycline