%0 Journal Article
%T Extracellular Matrix Remodeling of the Umbilical Cord in Pre-eclampsia as a Risk Factor for Fetal Hypertension
%A Lech Romanowicz
%A Zofia Galewska
%J Journal of Pregnancy
%D 2011
%I Hindawi Publishing Corporation
%R 10.1155/2011/542695
%X The human umbilical cord forms a connection between the placenta and the foetus. It is composed of two arteries and one vein surrounded by Wharton's jelly. Pre-eclampsia is accompanied by extensive remodeling of extracellular matrix of umbilical cord. Matrix metalloproteinases (MMPs) are engaged in degradation of extracellular matrix proteins and activation/inactivation of certain cytokines and enzymes. These enzymes will probably play a central role in the release of matrix-embedded cytokines and growth factors. MMP-2 (gelatinase A) is the main collagenolytic enzyme of both umbilical artery and vein. Other metalloproteinases are present in several times lower amounts. Reduced activity of collagen-degrading enzymes may be a factor, which enhances the accumulation of collagen and some other proteins in the pre-eclamptic umbilical cord tissues. It seems to be possible that similar alterations occur in other fetal blood vessels. It may result in an increase in peripheral resistance as well as an increase in the blood pressure in the fetal vascular system. Some observations suggest that the raised pressure may persist after birth. Pre-eclampsia may be a factor that evokes an initiation of hypertension in utero and its amplification through childhood and adulthood. 1. Structure of the Umbilical Cord The human umbilical cord forms a connection between the placenta and the foetus. It is composed of three blood vessels of different structure and function, one vein, which transports oxygenated and nutrition-rich blood from placenta to foetus, and two arteries, which transport deoxygenated blood and metabolic waste products from foetus to placenta. All these vessels are surrounded by Wharton¡¯s jelly [1], which constitutes the major part of human umbilical cord and provides a thick protective mantle around vessels. Wharton¡¯s jelly plays also an important role as a storage for some compounds, such as growth factors [2]. The extracellular matrix (ECM) in the vascular wall contains many macromolecules (collagen, elastin, proteoglycans, and glycoproteins) necessary for the structural and functional properties of vessel wall [3]. Proteolysis is a major process leading to changes in the ECM [4]. 2. Remodeling of the Umbilical Cord in Pre-eclampsia 2.1. Umbilical Cord Artery It was found in our studies that pre-eclampsia is accompanied by an extensive remodelling of the ECM of the umbilical cord. The umbilical cord arteries (UCAs) of newborns delivered by mothers with pre-eclampsia contain more than twice the amount of collagen and markedly less elastin in comparison to
%U http://www.hindawi.com/journals/jp/2011/542695/