Hormone regulation of endothelial apoptosis and proliferation in vessel regression and angiogenesis

Age-related Impairment of Vascular Structure and Functions

Among age-related diseases, cardiovascular and cerebrovascular diseases are major causes of death. Vascular dysfunction is a key characteristic of these diseases wherein age is an independent and essential risk factor. The present work will review morphological alterations of aging vessels in-depth, which includes the discussion of age-related microvessel loss and changes to vasculature involving the capillary basement membrane, intima, media, and adventitia as well as the accompanying vascular dysfunctions arising from these alterations.

Trophoblastic debris modifies endothelial cell transcriptome in vitro: a mechanism by which fetal cells might control maternal responses to pregnancy

The mechanisms by which the fetus induces maternal physiological adaptations to pregnancy are unclear. Cellular debris, shed from the placental syncytiotrophoblast into the maternal blood and phagocytosed by maternal endothelial and immune cells, may be one of these mechanisms. Here we show that trophoblastic debris from normal first trimester placentae induces changes in the transcriptome and proteome of endothelial cells in vitro, which might contribute to the adaptation of the maternal cardiovascular system to pregnancy. Trophoblastic debris also induced endothelial cells to transcribe placenta-specific genes, including the vasodilator hormone CSH1, thereby expanding the effective functional size of the placenta. Our data suggest that the deportation of trophoblastic debris is an important part of the complex network of feto-maternal communication.

Enhanced anti-angiogenic effect of a deletion mutant of plasminogen kringle 5 on neovascularization

Kringle 5 (K5), a proteolytic fragment of plasminogen, has been proved to be an angiogenic inhibitor. Previously, we have evaluated the effect of K5 on the vascular leakage and neovascularization in a rat model of oxygen-induced retinopathy. In this study, we expressed K5 and a deletion mutant of K5 (K5 mutant) in a prokaryocyte expression system and purified them by affinity chromatography. K5 mutant was generated by deleting 11 amino acids from K5 while retaining the three disulfide bonds. The anti-angiogenic activity of intact K5 and K5 mutant were compared in endothelial cells and retinal neovascularization rat model. K5 mutant inhibited the proliferation of primary human retinal capillary endothelial cells (HRCEC) in a concentration-dependent manner, with an apparent EC50 of approximate 35 nmol/L, which is twofold more potent than intact K5. In the even higher concentration range, K5 mutant did not inhibit pericytes from the same origin of HRCEC, which suggested an endothelial cell-specific inhibition. K5 mutant had no effect on normal liver cells and Bel7402 hepatoma cells even at high concentration range either. Intravitreal injection of the K5 and mutant in the oxygen-induced retinopathy rat model both resulted in significantly fewer neovascular tufts and nonperfusion area than controls with PBS injection, as shown by fluorescein angiography. Furthermore, K5 mutant exhibited more strong inhibition effect on neovascularization than intact K5 by quantification of vascular cells. These results suggest that this K5 deletion mutant is a more potent angiogenic inhibitor than intact K5 and may have therapeutic potential in the treatment of those disorders with neovascularization, such as solid tumor, diabetic retinopathy, age-related macular degeneration, rheumatoid arthritis, and hyperplasia of prostate.