title: Increased expression of endocan in arthritic synovial tissues: effects of adiponectin on the expression of endocan in fibroblast-like synoviocytes.
abstract: This study was performed to evaluate whether endocan expression, which is known to be involved in tumor angiogenesis, was increased in rheumatoid arthritic tissues. In addition, the involvement of adiponectin in the regulation of endocan expression in arthritic joints was examined. Arthritic synovial tissues from patients with rheumatoid arthritis (RA) or osteoarthritis (OA) were immunostained with antibodies to endocan and vascular endothelial growth factor (VEGF). Subsequently, synovial cells and human umbilical vein endothelial cells were cultured and stimulated with interleukin-1 β (IL-1β) or adiponectin. The mRNA and protein levels of endocan were evaluated by polymerase chain reaction and ELISA, respectively. Endocan expression was markedly increased in the inflammatory sites of RA synovial tissues. In OA tissues, endocan expression was higher in tissues displaying moderate and severe inflammation than in those with mild inflammation. In vitro expression levels of endocan and VEGF in endothelial and synovial cells were differentially increased in response to IL-1β stimulation. Adiponectin was a more potent stimulant of endocan than IL-1β at their respective physiological concentrations in synovial cells. Endocan silencing by small interfering RNA transfection of synovial cells decreased in vitro cell migration and invasion. In conclusion, adiponectin is an important factor in the stimulation of endocan expression in synovial cells. Adiponectin-induced endocan expression in synovial cells may stimulate cell migration and invasion as well as angiogenesis in the pannus of arthritic joints.
authors.affiliation: East-West Bone and Joint Research Institute, Kyung Hee University Hospital at Gangdong, Kyung Hee University, Seoul 134-727, Republic of Korea.
authors.forename: Kyoung Soo
authors.initials: KS
authors.lastname: Kim
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, Kyung Hee University Medical School, Seoul 134-727, Republic of Korea.
authors.forename: Yeon-Ah
authors.initials: YA
authors.lastname: Lee
authors.affiliation: East-West Bone and Joint Research Institute, Kyung Hee University Hospital at Gangdong, Kyung Hee University, Seoul 134-727, Republic of Korea.
authors.forename: Hye-In
authors.initials: HI
authors.lastname: Ji
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, Kyung Hee University Medical School, Seoul 134-727, Republic of Korea.
authors.forename: Ran
authors.initials: R
authors.lastname: Song
authors.affiliation: Department of Pathology, Inje University Sanggye Paik Hospital, Seoul 139-707, Republic of Korea.
authors.forename: Jung Yeon
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, Kyung Hee University Medical School, Seoul 134-727, Republic of Korea.
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, Kyung Hee University Medical School, Seoul 134-727, Republic of Korea.
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Hong
authors.affiliation: East-West Bone and Joint Research Institute, Kyung Hee University Hospital at Gangdong, Kyung Hee University, Seoul 134-727, Republic of Korea.
authors.forename: Myung Chul
authors.initials: MC
authors.lastname: Yoo
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, Kyung Hee University Medical School, Seoul 134-727, Republic of Korea.
authors.forename: Hyung-In
authors.initials: HI
authors.lastname: Yang
mesh_terms: D052242:Adiponectin / Q000378:metabolism / Q000494:pharmacology; D001168:Arthritis / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D001172:Arthritis, Rheumatoid / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002465:Cell Movement / Q000187:drug effects; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D015870:Gene Expression; D055785:Gene Knockdown Techniques; D006801:Humans; D007150:Immunohistochemistry; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism; D010003:Osteoarthritis / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D011509:Proteoglycans / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D013583:Synovial Membrane / Q000166:cytology / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
chemical_list: D052242:Adiponectin; C101134:ESM1 protein, human; D009363:Neoplasm Proteins; D011509:Proteoglycans; D034741:RNA, Small Interfering; D042461:Vascular Endothelial Growth Factor A