Immunohistochemical Expression of Prosaposin in the Normal Arteries and Atherosclerosis.
Seok J Park, Chu H Lee, Jae R Kim, Joon H Choi. Yeungnam University College of Medicine, Daegu, Korea; Yeungnam University College of Medicine, Aging-Associated Vascular Disease Research Center, Daegu, Korea
Background: Prosaposin, a glycoprotein encoded by a single locus on human chromosome 10, is the precursor of four sphingolipid activator proteins named saposin A, B, C, and D that activate the hydrolysis of sphingolipids by lysosomal hydrolases. It is an intriguing, ubiquitous, and highly conserved protein believed to be involved in a variety of biological processes. To investigate the role of prosaposin on the vascular aging and atherosclerosis, we analyzed expression of prosaposin in normal young arteries, normal old arteries, and atherosclerosis.
Design: Eighteen cases of normal young arteries (aged 1 to 38 years), eighteen cases of normal old arteries (aged 47 to 70 years), and eighteen cases of atherosclerosis were selected from surgically resected specimens at Yeungnam University Hospital during from 2002 to 2009. Immunohistochemical stain for prosaposin was done. Expression of prosaposin was scored semiquantatively by the intensity and proportion of immunostaining.
Results: All normal young arteries showed no expression of prosaposin (0 of 18 cases, 0%). Normal old arteries showed increased expression of prosaposin (6 of 18 cases, 33%). Prosaposin was expressed in the cytoplasm of smooth muscle cells and endothelial cells and the vascular wall in normal old arteries. All atherosclerosis cases showed markedly increased expression of prosaposin (18 of 18 cases, 100%). Expression of prosaposin was present in the cytoplasm of smooth muscle cells and macrophages, and the atheromatous plaque in the atherosclerosis.
Conclusions: Our findings suggest that prosaposin might be play a role in the progression of vascular aging and the development of atherosclerosis.
Wednesday, March 2, 2011 1:00 PM
Poster Session VI # 35, Wednesday Afternoon