Local osteoprotegerin gene transfer to periodontal tissue inhibits lipopolysaccharide-induced alveolar bone resorption.
OBJECTIVE
Osteoclastogenesis is primarily activated by receptor activator of nuclear factor kappaB ligand (RANKL) and is inhibited by osteoprotegerin (OPG). A previous study demonstrated that local OPG gene transfer to periodontal tissue inhibited RANKL-mediated osteoclastogenesis and experimental tooth movement. In the present study, we tested the hypothesis that local OPG gene transfer to the periodontium can neutralize RANKL activity induced by lipopolysaccharide injection, thereby inhibiting osteoclastogenesis and diminishing alveolar bone resorption in experimental periodontal disease.


METHODS
Seven-week-old male Wistar rats received an injection of lipopolysaccharide or phosphate-buffered saline in the palatal gingiva of the upper first molars on both the right and left sides. An inactivated haemagglutinating virus of Japan (HVJ) envelope vector containing a mouse OPG expression plasmid [pcDNA3.1(+)-mOPG] or mock vector was injected periodically into the palatal periodontal tissue of the upper first molars.


RESULTS
Lipopolysaccharide injection induced severe periodontal bone resorption. Local OPG gene transfer induced OPG production, and osteoclastogenesis was inhibited. Local OPG gene transfer significantly decreased alveolar bone resorption.


CONCLUSIONS
Osteoprotegerin gene transfer to periodontal tissue inhibited osteoclastogenesis and alveolar bone resorption in lipopolysaccharide-induced experimental periodontal disease.
Chen
Rui
R
Division of Oral Dysfunction Science, Department of Oral Health and Developmenet Sciences, Graduate School of Dentistry, Tohoku University, Sendai, Japan.
Kanzaki
Hiroyuki
H
Chiba
Mirei
M
Nishimura
Makoto
M
Kanzaki
Reiko
R
Igarashi
Kaoru
K
D016301:Alveolar Bone Loss / Q000517:prevention & control*; D000818:Animals; D049109:Cell Proliferation; D005822:Genetic Vectors; D005881:Gingiva; D007150:Immunohistochemistry; D008070:Lipopolysaccharides / Q000008:administration & dosage; D008297:Male; D051379:Mice; D010010:Osteoclasts / Q000502:physiology; D053244:Osteoprotegerin / Q000096:biosynthesis / Q000235:genetics* / Q000502:physiology*; D053245:RANK Ligand / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D029082:Sendai virus; D018709:Statistics, Nonparametric; D014162:Transfection / Q000379:methods*
D008070:Lipopolysaccharides; D053244:Osteoprotegerin; D053245:RANK Ligand