MR molecular imaging of aortic angiogenesis

Area of Science:

• Cardiovascular Research
• Molecular Imaging
• Metabolic Syndrome Research

Background:

• The JCR:LA-cp rat is a model for metabolic syndrome, exhibiting obesity and vasculopathy.
• Plaque neovascularity in this model has not been previously reported.
• Alpha(nu)beta(3)-targeted nanoparticles with MR molecular imaging can map aortic angiogenesis.

Purpose of the Study:

• To characterize aortic neovascular development in a rat model of atherosclerosis using MR molecular imaging.
• To monitor the effects of benfluorex, an appetite suppressant, on vascular angiogenesis progression.

Main Methods:

• Obese (JCR:LA-cp cp/cp) and lean (JCR:LA-cp +/?) rats were studied over 16 weeks.
• Six obese rats received benfluorex; controls received standard chow.
• MR molecular imaging with alpha(nu)beta(3)-targeted paramagnetic nanoparticles was performed serially.

Main Results:

• Untreated obese rats showed increased aortic signal enhancement, indicating angiogenesis, paralleled by increased microvessel counts.
• Benfluorex treatment suppressed angiogenesis and reduced food consumption, body weight, insulin, and leptin levels.
• No significant signal changes were observed in lean or benfluorex-treated rats.

Conclusions:

• Neovascular expansion is a significant feature of atherosclerosis in the JCR:LA-cp rat model.
• MR imaging with alpha(nu)beta(3)-targeted nanoparticles offers a noninvasive method to assess angiogenesis.
• Benfluorex effectively suppressed angiogenesis in this obese rat model.