1042-84 Elevated plasma level of placental growth factor is correlated with peripheral monocyte fraction in patients with acute myocardial infarction

Abstract

Bone mallow derived stem cells (BMSM) participate in wound healing and regeneration of infarct tissue in acute myocardial infarction (AMI). However, it remains unknown how infarct heart tissue stimulates and recruits BMSC to the injured heart. Placental growth factor (PlGF) stimulates angiogenesis through binding to VEGF receptor-1, and induces BMSC peripheral mobilization. Accordingly, we studied plasma PlGF levels and white blood cell profile after AMI in human, and also studied the heart tissue expression of PlGF of AMI mouse model. Method and Results: 35 patients AMI were enrolled. The plasma PlGF levels of AMI patients significantly increased compared with controls (36.8 + /−31.9, 13.3 + /−5.2 pg/ml, p < 0.0001). Monocyte fraction was elevated in peripheral blood from 3rd to 7th day of AMI, and PlGF positively correlated to peak monocyte fraction (r = 0.496, p < 0.005). Plasma levels of VEGF elevated in AMI, but did not correlate to monocyte fraction. In AMI mouse, PlGF mRNA expression was significantly (26.6 folds, p < 0.001) increased in infarct heart compared with sham operated heart. Furthermore, immunohistochemical staining showed that PlGF protein was overexpressed mainly in vascular tissue in infarct region, but scarcely in non-infarct region. Vascular expression of PlGF protein was not detected in sham-operated heart. Conclusion: Elevated plasma PlGF might have effect on the recruitment of monocyte, as well as vascular progenitor cells, from bone marrow to peripheral circulation.