title: [Effect of caspase-dependent pathway on apoptosis of human gingival fibroblasts induced by advanced glycation end products].
abstract: OBJECTIVE
  To investigate the effect of synthesized advanced glycation end products (AGE) on apoptosis of human gingival fibroblasts (HGF) and the possible role of caspase-dependent pathway in the process of AGE-induced apoptosis.
  
  
  METHODS
  HGF were incubated with AGE-human serum albumin (AGE-HSA). The activity of caspase-8, caspase-9 and caspase-3 were detected by microplate reader after 12 and 24 hours. HGF were incubated with caspase inhibitors for 1 hour, and then incubated with AGE-HSA for 24 hours, HGF was first stained by Hoechst33258 and observed under inverted microscope, and then double stained by annexin V and propidine iodide (PI) and observed by flow cytometry (FCM). The activity of caspase-3 was determined by caspase-3 assay kit and observed by microplate reader.
  
  
  RESULTS
  Caspases activity of caspase-8, -9, -3 was 0.1097 ± 0.0051, 0.0965 ± 0.0051 and 0.1280 ± 0.0103 after 12 h of incubation with AGE-HSA and HGF, respectively, and 0.1558 ± 0.0053, 0.1308 ± 0.0035 and 0.1954 ± 0.0051 after 24 h of incubation with AGE-HSA and HGF, respectively (P < 0.05). Positive cells number was 247.7 ± 32.4, 200.1 ± 14.6, 154.1 ± 14.4 and 131.3 ± 14.6 in caspase inhibitor groups by Hoechst33258 staining, respectively. Apoptotic rate was (25.57 ± 2.20)%, (38.87 ± 3.31)%, (17.17 ± 2.24)% and (14.73 ± 2.48)% in caspase inhibitor groups by annexin V-PI staining, respectively. The difference between different groups was significant (P < 0.05). Caspase-3 activity was reduced to 0.1274 ± 0.0076, 0.1465 ± 0.0062, 0.1044 ± 0.0051 in caspase inhibitor groups, respectively. The difference between different groups was significant (P < 0.05).
  
  
  CONCLUSIONS
  Apoptosis of HGF induced by AGE-HSA may be mainly through activation of caspase-dependant pathway in which cytoplasmic pathway may play a predominant role.
authors.affiliation: Department of Periodontology, Guanghua School and Hospital of Stomatology & Institute of Stomatological Research, Sun Yat-sen University, Guangzhou 510055, China.
authors.forename: Kai-Lei
authors.initials: KL
authors.lastname: Liu
authors.forename: Shao-Jie
authors.initials: SJ
authors.lastname: Yu
authors.forename: Yun
authors.initials: Y
authors.lastname: Fu
mesh_terms: D000293:Adolescent; D000328:Adult; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D061945:Caspase Inhibitors / Q000494:pharmacology*; D020169:Caspases / Q000378:metabolism*; D002478:Cells, Cultured; D002648:Child; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D005881:Gingiva / Q000166:cytology*; D017127:Glycation End Products, Advanced / Q000494:pharmacology*; D006801:Humans; D009842:Oligopeptides / Q000494:pharmacology; D012709:Serum Albumin / Q000494:pharmacology*; D000075462:Serum Albumin, Human; D015398:Signal Transduction; D055815:Young Adult
chemical_list: D061945:Caspase Inhibitors; D017127:Glycation End Products, Advanced; D009842:Oligopeptides; D012709:Serum Albumin; C109748:advanced glycation end products-human serum albumin; C110772:benzoylcarbonyl-aspartyl-glutamyl-valyl-aspartyl-fluoromethyl ketone; C403753:benzyloxycarbonyl-isoleucyl-glutamyl-threonyl-aspartic acid fluoromethyl ketone; C403754:benzyloxycarbonyl-leucyl-glutamyl-histidyl-aspartic acid fluoromethyl ketone; C505407:CASP3 protein, human; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases; D000075462:Serum Albumin, Human