Up-regulation of osteolytic mediators in human osteosarcoma cells stimulated with nicotine.
OBJECTIVE
Cigarette smoking is a major risk factor in the development and further progression of periodontal diseases. However, little is known about how nicotine influences the expression of osteolytic mediators in cigarette smoking-associated periodontal diseases. The aim of this study was to investigate the expression of interleukin-1, interleukin-8, receptor activator of nuclear factor-kappaB ligand (RANKL), gelatinases and tissue-type plasminogen activator in U2OS cells (from the human osteosarcoma cell line) stimulated with nicotine.


METHODS
Differences in the expression of interleukin-1, interleukin-8 and RANKL mRNAs, in response to exposure to various concentrations of nicotine (0, 0.125, 0.25, 0.5 and 1 mm) were evaluated in U2OS cells using the reverse transcription-polymerase chain reaction.In addition, the levels of interleukin-1, interleukin-8 and RANKL proteins were determined using enzyme-linked immunosorbent assays. The gelatinolytic and caseinolytic activities in nicotine treated-U2OS cells were demonstrated using gelatin and casein zymography, respectively.


RESULTS
Nicotine was found to increase the expression of interleukin-1, interleukin-8 and RANKL mRNA and protein in U2OS cells (p < 0.05). The gelatin zymograms revealed that matrix metalloproteinase (MMP)-2 and MMP-9 were secreted by U2OS cells. The secretion of MMP-2 and MMP-9 occurred in a dose-dependent manner that was dependent on the concentration of nicotine (p < 0.05). Casein zymography exhibited a caseinolytic band with a molecular weight of 70 kDa, indicative of the presence of tissue-type plasminogen activator. Tissue-type plasminogen activator was also found to be up-regulated by nicotine in a dose-dependent manner (p < 0.05).


CONCLUSIONS
Taken together, the results of the present study indicated that smoking modulation of bone destruction in periodontal disease may involve various osteolytic mediators, such as interleukin-1, interleukin-8, RANKL, MMP-2, MMP-9, and tissue-type plasminogen activator.
Ho
Y-C
YC
School of Applied Chemistry, Chung Shan Medical University, Taichung, Taiwan.
Yang
S-F
SF
Huang
F-M
FM
Chang
Y-C
YC
D002364:Caseins / Q000187:drug effects; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D018093:Gelatinases / Q000187:drug effects; D006801:Humans; D007375:Interleukin-1 / Q000032:analysis; D016209:Interleukin-8 / Q000187:drug effects; D020778:Matrix Metalloproteinase 2 / Q000187:drug effects; D020780:Matrix Metalloproteinase 9 / Q000187:drug effects; D008970:Molecular Weight; D009538:Nicotine / Q000008:administration & dosage / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D010014:Osteolysis / Q000503:physiopathology*; D012516:Osteosarcoma / Q000503:physiopathology*; D053245:RANK Ligand / Q000187:drug effects; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000187:drug effects; D015854:Up-Regulation
D002364:Caseins; D007375:Interleukin-1; D016209:Interleukin-8; D018722:Nicotinic Agonists; D053245:RANK Ligand; D009538:Nicotine; D010959:Tissue Plasminogen Activator; D018093:Gelatinases; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9