TY - JOUR
T1 - A local proinflammatory signalling loop facilitates adverse age-associated arterial remodeling
AU - Wang, Mingyi
AU - Spinetti, Gaia
AU - Monticone, Robert E.
AU - Zhang, Jing
AU - Wu, James
AU - Jiang, Liqun
AU - Khazan, Benjamin
AU - Telljohann, Richard
AU - Lakatta, Edward G.
PY - 2011
Y1 - 2011
N2 - Background: The coincidence of vascular smooth muscle cells (VSMC) infiltration and collagen deposition within a diffusely thickened intima is a salient feature of central arterial wall inflammation that accompanies advancing age. However, the molecular mechanisms involved remain undefined. Methodology/Principal Findings: Immunostaining and immunoblotting of rat aortae demonstrate that a triad of proinflammatory molecules, MCP-1, TGF-β1, and MMP-2 increases within the aortic wall with aging. Exposure of VSMC isolated from 8-mo-old rats (young) to MCP-1 effects, via CCR-2 signaling, both an increase in TGF-β1 activity, up to levels of untreated VSMC from 30-mo-old (old) rats, and a concurrent increase in MMP-2 activation. Furthermore, exposure of young VSMC to TGF-β1 increases levels of MCP-1, and MMP-2 activation, to levels of untreated VSMC from old rats. This autocatalytic signaling loop that enhances collagen production and invasiveness of VSMC is effectively suppressed by si-MCP-1, a CCR2 antagonist, or MMP-2 inhibition. Conclusions/Significance: Threshold levels of MCP-1, MMP-2, or TGF-β1 activity trigger a feed-forward signaling mechanism that is implicated in the initiation and progression of adverse age-associated arterial wall remodeling. Intervention that suppressed this signaling loop may potentially retard age-associated adverse arterial remodeling.
AB - Background: The coincidence of vascular smooth muscle cells (VSMC) infiltration and collagen deposition within a diffusely thickened intima is a salient feature of central arterial wall inflammation that accompanies advancing age. However, the molecular mechanisms involved remain undefined. Methodology/Principal Findings: Immunostaining and immunoblotting of rat aortae demonstrate that a triad of proinflammatory molecules, MCP-1, TGF-β1, and MMP-2 increases within the aortic wall with aging. Exposure of VSMC isolated from 8-mo-old rats (young) to MCP-1 effects, via CCR-2 signaling, both an increase in TGF-β1 activity, up to levels of untreated VSMC from 30-mo-old (old) rats, and a concurrent increase in MMP-2 activation. Furthermore, exposure of young VSMC to TGF-β1 increases levels of MCP-1, and MMP-2 activation, to levels of untreated VSMC from old rats. This autocatalytic signaling loop that enhances collagen production and invasiveness of VSMC is effectively suppressed by si-MCP-1, a CCR2 antagonist, or MMP-2 inhibition. Conclusions/Significance: Threshold levels of MCP-1, MMP-2, or TGF-β1 activity trigger a feed-forward signaling mechanism that is implicated in the initiation and progression of adverse age-associated arterial wall remodeling. Intervention that suppressed this signaling loop may potentially retard age-associated adverse arterial remodeling.
UR - http://www.scopus.com/inward/record.url?scp=79951566579&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79951566579&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0016653
DO - 10.1371/journal.pone.0016653
M3 - Article
C2 - 21347430
AN - SCOPUS:79951566579
SN - 1932-6203
VL - 6
JO - PloS one
JF - PloS one
IS - 2
M1 - e16653
ER -