title: Pericoronary Adipose Tissue as Storage and Supply Site for Oxidized Low-Density Lipoprotein in Human Coronary Plaques.
abstract: OBJECTIVE
  It is generally believed that low-density lipoprotein enters the vascular wall from its lumen and oxidized (oxLDL), after which it plays an important role in atherosclerosis. Because voluminous epicardial adipose tissue is a risk factor for coronary events, there is a possibility that the pericoronary adipose tissue (PCAT), which is a part of epicardial adipose tissue, acts as a risk factor by supplying oxLDL to the coronary arterial wall. The present study was performed whether PCAT stores and supplies oxLDL to the coronary wall.
  
  
  METHODS
  Localization of oxLDL in PCAT and its relation to plaque morphology were examined by immunohistochemical techniques in 27 epicardial coronary arteries excised from 9 human autopsy cases.
  
  
  RESULTS
  OxLDL deposited in all PCAT of the studied cases. The percent (%) incidence of oxLDL in the intima of 25 normal segment, 19 white plaques, 15 yellow plaques without necrotic core (NC) and 10 yellow plaques with NC, was 32, 84, 93 (p<0.05 vs normal segments and yellow plaques with NC), and 30, respectively. OxLDL deposited either in dotted or diffuse pattern. Double immunohistochemical staining revealed that the dotted oxLDL was that contained in CD68(+)-macrophages. The oxLDL-containing macrophages were observed in the interstitial space but not inside of the vasa vasorum, and they traversed PCAT, adventitia, external and internal elastic laminae, suggesting their migration towards the intima. Diffuse oxLDL deposits were observed in 17 preparations, the majority of which were co-localized with the vasa vasorum in outer or in both inner and outer halves of intima, and rarely in the inner half alone.
  
  
  CONCLUSIONS
  The results suggested that PCAT is a supply source of oxLDL to coronary intima and acts as a risk factor for coronary events, that oxLDL increasingly deposits in the intima with plaque growth and decreases after plaque maturation, and therefore molecular therapies targeting the PCAT before plaque growth could be effective in preventing human coronary atherosclerosis.
authors.affiliation: Japanese Foundation for Cardiovascular Research, Funabashi, Japan.|Department of Cardiology, Tokyo Jikei University School of Medicine, Tokyo, Japan.
authors.forename: Yasumi
authors.initials: Y
authors.lastname: Uchida
authors.affiliation: Department of Cardiology, Tsukuba Memorial Hospital, Tsukuba, Japan.
authors.forename: Yasuto
authors.initials: Y
authors.lastname: Uchida
authors.affiliation: Department of Pathology, Funabashi-Futawa Hospital, Funabashi, Japan.
authors.forename: Ei
authors.initials: E
authors.lastname: Shimoyama
authors.affiliation: Department of Pathology, Toho University Sakura Medical Center, Sakura, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Hiruta
authors.affiliation: Department of Biomolecular Science, Faculty of Science, Toho University, Okubo, Funabashi, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Kishimoto
authors.affiliation: Department of Biomolecular Science, Faculty of Science, Toho University, Okubo, Funabashi, Japan.
authors.forename: Soichiro
authors.initials: S
authors.lastname: Watanabe
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism / Q000473:pathology*; D015703:Antigens, CD / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D001344:Autopsy; D003331:Coronary Vessels / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D008077:Lipoproteins, LDL / Q000032:analysis* / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000378:metabolism / Q000473:pathology*; D017539:Tunica Intima / Q000378:metabolism / Q000473:pathology; D014651:Vasa Vasorum / Q000378:metabolism / Q000473:pathology
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; C062279:CD6 antigen; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein