title: Expression of matrix metalloproteinases-2, -9 and reversion-inducing cysteine-rich protein with Kazal motifs in gingiva in periodontal health and disease.
abstract: OBJECTIVE
  Periodontitis is characterized by pathological destruction of extracellular matrix (ECM) of periodontal tissues. Matrix metalloproteinases (MMPs) promote the occurrence and development of periodontitis by degrading almost all proteins of ECM. RECK (reversion-inducing-cysteine-rich protein with kazal motifs), a novel membrane-anchored inhibitor of MMPs, could regulate the expression of MMP-2 and MMP-9 at post-transcriptional level. The study was to investigate the expression of RECK in healthy and diseased human gingival tissues and to correlate it with the production of MMP-2 and MMP-9.
  
  
  METHODS
  Gingival biopsies were collected from chronic periodontitis patients and periodontally healthy control individuals. The protein and mRNA of RECK, MMP-2 and MMP-9 was determined by immunohistochemistry and semi-quantitative polymerase chain reaction analysis.
  
  
  RESULTS
  The expression of RECK protein was mainly confined to the gingival epithelium in inflamed and non-inflamed gingival tissues. Expression of RECK was significantly lower in tissues from chronic periodontitis patients, while the positive expression levels of MMP-2 and MMP-9 in periodontitis specimens were significantly higher. RECK protein expression was negatively correlated to the expressions of MMP-2 and MMP-9 in periodontitis. Moreover, RECK mRNA was significanly lower in diseased gingiva than in healthy samples(P<0.05), while MMP-2 and MMP-9 mRNAs were observed overexpressed in periodontal lesions, with no significant correlation between RECK and MMP-2/MMP-9 mRNA shown in periodontally diseased group.
  
  
  CONCLUSIONS
  The expression of RECK in human healthy and diseased gingiva may contribute to periodontal physiological and pathological processes; low RECK expression may be associated with the enhanced MMP-2 and MMP-9 production in inflamed gingiva.
authors.affiliation: Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Nian
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Yingguang
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China. Electronic address: zhuguangxun@163.com.
authors.forename: Guangxun
authors.initials: G
authors.lastname: Zhu
mesh_terms: D001706:Biopsy; D055113:Chronic Periodontitis / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism / Q000473:pathology; D005109:Extracellular Matrix / Q000378:metabolism; D058851:GPI-Linked Proteins / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D005881:Gingiva / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism*; D010518:Periodontitis / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D058851:GPI-Linked Proteins; C115460:RECK protein, human; D012333:RNA, Messenger; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9
keywords: Chronic periodontitis; Gingiva; Immunohistochemistry; MMP-2; MMP-9; Polymerase chain reaction; RECK