title: Butyrate induces reactive oxygen species production and affects cell cycle progression in human gingival fibroblasts.
abstract: OBJECTIVE
  Short-chain fatty acids, such as butyric acid and propionic acid, are metabolic by-products generated by periodontal microflora such as Porphyromonas gingivalis, and contribute to the pathogenesis of periodontitis. However, the effects of butyrate on the biological activities of gingival fibroblasts (GFs) are not well elucidated.
  
  
  METHODS
  Human GFs were exposed to various concentrations of butyrate (0.5-16 mm) for 24 h. Viable cells that excluded trypan blue were counted. Cell cycle distribution of GFs was analyzed by propidium iodide-staining flow cytometry. Cellular reactive oxygen species (ROS) production was measured by flow cytometry using 2',7'-dichlorofluorescein (DCF). Total RNA and protein lysates were isolated and subjected to RT-PCR using specific primers or to western blotting using specific antibodies, respectively.
  
  
  RESULTS
  Butyrate inhibited the growth of GFs, as indicated by a decrease in the number of viable cells. This event was associated with an induction of G0/G1 and G2/M cell cycle arrest by butyrate (4-16 mm) in GFs. However, no marked apoptosis of GFs was noted in this experimental condition. Butyrate (> 2 mm) inhibited the expression of cdc2, cdc25C and cyclinB1 mRNAs and reduced the levels of Cdc2, Cdc25C and cyclinB1 proteins in GFs, as determined using RT-PCR and western blotting, respectively. This toxic effect of butyrate was associated with the production of ROS.
  
  
  CONCLUSIONS
  These results suggest that butyrate generated by periodontal pathogens may be involved in the pathogenesis of periodontal diseases via the induction of ROS production and the impairment of cell growth, cell cycle progression and expression of cell cycle-related genes in GFs. These events are important in the initiation and prolongation of inflammatory processes in periodontal diseases.
authors: Biomedical Science Team, Chang Gung University of Science and Technology, Taoyuan, Taiwan.
authors: M-C
authors: MC
authors: Chang
authors: Y-L
authors: YL
authors: Tsai
authors: Y-W
authors: YW
authors: Chen
authors: C-P
authors: CP
authors: Chan
authors: C-F
authors: CF
authors: Huang
authors: W-C
authors: WC
authors: Lan
authors: C-C
authors: CC
authors: Lin
authors: W-H
authors: WH
authors: Lan
authors: J-H
authors: JH
authors: Jeng
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D002087:Butyrates / Q000494:pharmacology* / Q000633:toxicity; D016203:CDC2 Protein Kinase; D018929:Cell Culture Techniques; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents; D019926:Cyclin B / Q000187:drug effects; D056744:Cyclin B1 / Q000187:drug effects; D018844:Cyclin-Dependent Kinases; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects*; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins; D005456:Fluorescent Dyes; D059585:G1 Phase Cell Cycle Checkpoints / Q000187:drug effects; D059565:G2 Phase Cell Cycle Checkpoints / Q000187:drug effects; D005881:Gingiva / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D059566:M Phase Cell Cycle Checkpoints / Q000187:drug effects; D011419:Propidium; D017382:Reactive Oxygen Species / Q000378:metabolism*; D016192:Resting Phase, Cell Cycle / Q000187:drug effects; D020687:cdc25 Phosphatases / Q000187:drug effects
chemical_list: D002087:Butyrates; C534699:CCNB1 protein, human; D004396:Coloring Agents; D019926:Cyclin B; D056744:Cyclin B1; D005452:Fluoresceins; D005456:Fluorescent Dyes; D017382:Reactive Oxygen Species; D011419:Propidium; C037631:2',7'-dichlorofluorescein; D016203:CDC2 Protein Kinase; C528899:CDK1 protein, human; D018844:Cyclin-Dependent Kinases; C517009:CDC25C protein, human; D020687:cdc25 Phosphatases; D016650:Fluorescein-5-isothiocyanate