Baseline patient characteristics of the PHAST population.

<p>Median [inter quartile range].</p><p>*) significant difference between the two groups (P<0.05). Abbreviations: BMI, body mass index; ApoA, apolipoprotein A; ApoB, apolipoprotein B.</p><p>Baseline patient characteristics of the PHAST population.</p

Plaque Rupture Complications in Murine Atherosclerotic Vein Grafts Can Be Prevented by TIMP-1 Overexpression

<div><p>The current study describes the incidence and phenotype of plaque rupture complications in murine vein grafts. Since matrix metalloproteinases (MMPs) are highly involved in atherosclerotic plaque vulnerability and plaque rupture, we hypothesized that this model can be validated by overexpression of the MMP inhibitor TIMP-1. First we studied 47 vein grafts in hypercholesterolemic ApoE3*Leiden mice for the incidence of plaque complications. In 79% of these grafts, extensive lesions with plaque rupture complications like dissections, intraplaque hemorrhages or erosions with intramural thrombi were found. Next, <em>in vivo</em> Near-InfraRed-Fluorescence imaging demonstrated that electroporation mediated TIMP-1-overexpression reduced local MMP activity in vein grafts by 73% (p<0.01). This led to a 40% reduction in lesion-size after 28d (p = 0.01) and a more stable lesion phenotype with significant more smooth muscle cells (135%), collagen (47%) and significant less macrophages (44%) and fibrin (55%) than controls. More importantly, lesions in the TIMP-1 group showed a 90% reduction of plaque complications (10/18 of control mice showed plaque complications versus 1/18 in TIMP-1 treated mice). Murine vein grafts are a relevant spontaneous model to study plaque stability and subsequent hemorrhagic complications, resulting in plaque instability. Moreover, inhibition of MMPs by TIMP-1-overexpression resulted in decreased plaque progression, increased stabilization and decreased plaque rupture complications in murine vein grafts.</p> </div

Ramipril reduces (P<0.004) macrophage activation as assessed by CD68/HLA-Dr double staining and increases aortic wall M2 content (CD68/CD163 double positive cells, P<0.006) content, thus resulting in a shift in the M1/M2 balance (P<0.002).

<p>Cell counts are based on the number of double positive cells per 6 medium power fields. Cell content is expressed as the number of cells per mm². Non-treated controls (white bars); ramipril-treated patients (grey bars).</p

Effect of ramipril on aneurysm wall leucocyte content.

<p>Semi-quantitative analysis of aortic wall monocyte/macrophage (CD68), neutrophil (myeloperoxidase (MPO)), B-cell (CD20), plasma cell (CD138), T-cell (CD3), T-helper cell (CD4), and cytotoxic T-cells (CD8). Cell counts are based on reflect the number of double positive cells per 6 medium power fields. Cell content is expressed as the number of cells per mm². Non-treated controls (white bars); ramipril-treated patients (grey bars). *P<0.009.</p

Relative mRNA expression of selected inflammatory mediators, proteases, cytokines, and cell activation markers (log transcript level relative to GAPDH (GAPDH = 0)).

<p>*⁾Significance reached after Benjamini-Hochberg correction.</p><p>Abbreviations: IL, interleukin; TNF-α, tumor necrosis factor-α; MCP-1, monocyte chemotactic protein-1; IFN-γ, interferon-γ; MMP, matrix metalloproteinase; TGF-β, transforming growth factor β; PAI-1, plasminogen activator inhibitor-1.</p><p>*⁾Snap frozen material was available from 10 patients.</p><p>Relative mRNA expression of selected inflammatory mediators, proteases, cytokines, and cell activation markers (log transcript level relative to GAPDH (GAPDH = 0)).</p

Aneurysm wall protein interleukin-6, interleukin-8, and monocyte chemoattractant protein 1 content.

<p>(*) levels significantly lower in Ramipril-treated individuals (P<0.014 and P<0.008 for IL-8 and MCP-1 respectively). Non-treated controls (white bars); Ramipril-treated patients (grey bars).</p

Baseline patient characteristics of the Ramipril intervention study.

<p>Median [inter quartile range].</p><p>Baseline patient characteristics of the Ramipril intervention study.</p

Quantification of vein grafts without complications (Control), and vein grafts with complications, namely plaque hemorrhage, dissections or erosions (n = 10/group).

<p><b>A</b>; Vessel wall area measurements <b>B</b>; Quantification of lumen area <b>C</b>; Total vessel area (combined lumen and vessel wall area, as a measure for outward remodeling) <b>D</b>; Correlation between the vessel wall area and the length of the plaque rupture complications.</p

Similar aneurysm progression in AAA patients using an ACE inhibitor (dashed line, n = 82) and those not using an ACE-inhibitor (solid line, n = 204) (data from the PHAST study¹⁷).

<p>The mean 18 month difference between AAA patients on an ACE inhibitor and those not was −0.24 mm (95% CI: −0.90–0.45 mm).</p

Quantitative measurements on vein graft lesions in mice that overexpress Luciferase, TIMP-1 or TIMP-3.

<p><b>A</b>; Representative cross-sections of vein grafts in mice 28 days after surgery (Hematoxilin-Phloxine-Saffron staining). <b>B</b>; Quantitative measurements of total vessel area, luminal area and lesion area <b>C</b>; Graph showing the length of the plaque rupture complications. <b>D</b>; Quantitative measurement of percentage collagen in vein grafts in Luciferase, TIMP-1 or TIMP-3 overexpressing mice. <b>E–G</b>; Quantitative measurement of percentage SMC actin, macrophages and fibrin <b>H–K;</b> Typical examples for all (immuno)histochemical stainings.</p