Expression and localization of the proteoglycan decorin during the progression of cholesterol induced atherosclerosis in Japanese quail: implicationsfor interaction with collagen type I and lipoproteins

The temporal and spatial distribution, and relative levels of the proteogly can decorin and collagen type I were examined during the progression of ath erosclerosis in the dorsal aortas of Japanese quail selected for cholestero l induced atherosclerosis. The quail were placed on either a control or 0.5 % added cholesterol diet at approximately 16 weeks of age. Dorsal aortas we re collected at 1- or 2-week intervals over a 15-week period after initiati ng cholesterol feeding. Biochemical analysis for decorin and collagen type I showed that both increased in the cholesterol-fed birds compared to contr ol-fed birds beginning at 9 weeks and continued through the duration of the study. Through immunohistochemical staining for decorin and collagen type I, the spatial localization of decorin and collagen type I in control and l ess severe plaques in cholesterol-fed birds was most prominent in the arter ial adventitia. However, in severe atherosclerotic plaques, decorin was loc alized in foam cell regions and collagen type I was found surrounding the f oam cell regions where decorin accumulated. These results demonstrated a lo calization of decorin in the core of the atherosclerotic plaque foam cell r egion with collagen type I bring located on the plaque surface. (C) 1999 El sevier Science Ireland Ltd. All rights reserved.