title: Advanced glycation end products inhibit the expression of collagens type I and III by human gingival fibroblasts.
abstract: BACKGROUND
  It is evident that diabetes and periodontal disease are closely interrelated. Accumulation of advanced glycation end products (AGEs), coupled with exaggerated host responses to bacterial infection, may account for the increased periodontal destruction observed in patients with uncontrolled diabetes. The present study investigated the effects of AGEs on the viability of human gingival fibroblasts (HGFs) and the expression of types I and III collagen in HGFs.
  
  
  METHODS
  The cell viability of HGFs was examined by methylthiazolet-etrazolium assay, whereas the expression of types I and III collagen message and protein was detected by real-time quantitative reverse transcription-polymerase chain reaction and sandwich enzyme-linked immunosorbent assay, respectively.
  
  
  RESULTS
  AGEs significantly suppressed the cell viability of HGFs from 24 to 72 hours (P <0.01). A high concentration of glucose (25 mmol/l) in the culture media exaggerated the inhibition of the survival rate of HGFs (P <0.01). The expression of collagen types I and III messages and proteins was significantly downregulated at 72 hours by AGEs in a concentration-dependent manner (P <0.05). Moreover, the synthesis of intracellular types I and III collagen protein was markedly inhibited by AGEs (P <0.05).
  
  
  CONCLUSIONS
  AGEs may suppress the cell viability of HGFs and downregulate the expression of types I and III collagen by the cells. Further investigations are warranted to clarify the molecular mechanisms of AGEs in the regulation of cell function and collagen metabolism in patients with diabetes and periodontitis.
authors: Department of Periodontology, Institute of Stomatological Research, Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, China.
authors: Lei
authors: L
authors: Ren
authors: Yun
authors: Y
authors: Fu
authors: Yuquan
authors: Y
authors: Deng
authors: Liuying
authors: L
authors: Qi
authors: Lijian
authors: L
authors: Jin
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D024042:Collagen Type I / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D024061:Collagen Type III / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D005881:Gingiva / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D017127:Glycation End Products, Advanced / Q000494:pharmacology*; D006801:Humans; D012333:RNA, Messenger / Q000032:analysis; D012016:Reference Values; D055815:Young Adult
chemical_list: D024042:Collagen Type I; D024061:Collagen Type III; D017127:Glycation End Products, Advanced; D012333:RNA, Messenger