Abstract 946: Therapeutic Role of Placenta Growth Factor in Post-Infarct Myocardial Revascularization
Limited options for myocardial revascularization are available for infarct patients not candidates for surgical or PTCA solutions. This research focuses on the therapeutic potential of using Placenta Growth Factor (PlGF) to treat these patients. PlGF, a member of the vascular endothelial growth factor family, plays a critical role in physiological development of vascular structures of placenta. It is one of the most naturally occurring growth factors and contributes to ensure adequate vascular development/function of the placenta early in gestation. PIGF is rapidly produced especially by endothelial cells during the acute phase of myocardial infarction. Purified PIGF isoforms have little or no direct mitogenic activity.
Methods 30 Wistar rats underwent myocardial infarct by LAD ligation. Seven days later, two groups were formed: a first group of 15 rats was injected with PlGF (150ng/15 μl) in 3 different areas of infarct. In the second control (sham) group 15 μl of the PlGF solvent was injected in the same manner in rat hearts. Thirty days after injections, animals were sacrificed, heart harvested and histopathological examinations were performed (histological and histochemical analysis, as well as morphometric assessment). Endothelial cells were identified with antibody anti factor VIII and the presence of elastic fibers in the vessels wall was identified by orcein staining.
Results Capillary density (CD) for vessels with diameter < 10 μm was 324 ± 126 for the sham group and 490 ± 186/ mm2 for the PlGF group (p<0.05). CD for vessels with diameter > 50 μm and elastic fiber wall was 4.5 ± 2.4 for the sham group and 12 ± 4.2 /mm2 for the PlGF group (p<0.01).
Conclusions In infarcted hearts, the local myocardial treatment with PlGF demonstrated the increase of angiogenic and arteriogenic activities. This approach deserves investigation as a therapeutic strategy to stimulate myocardial revascularization alone or associated with cell therapy in regenerative cardiology.