Anti-NGF treatment reduces bone resorption in periodontitis

Periodontitis is characterized by periodontal tissue destruction,including the alveolar bone. one of its critical components is the release of pro-inflammatory neuropeptides from sensory nerve endings innervating the periodontium. since nerve growth factor (ngf) has been reported to up-regulate neuropeptides in sensory neurons,we hypothesized that it would be increased in ligature-induced periodontitis in rats,and that systemic ngf neutralization would reduce the periodontitis-associated alveolar bone resorption. real-time pcr analysis disclosed a statistically significant time-dependent up-regulation of ngf mrna in gingiva during 2 weeks of periodontitis. interestingly,ngf up-regulation was also detected in the contralateral gingiva. in addition,immunohistochemistry of trigeminal ganglion neurons innervating the gingivomucosa demonstrated increased expression of trka receptor for ngf. systemic anti-ngf treatment during periodontitis significantly reduced interleukin-1β expression in gingiva and bilateral alveolar bone resorption. this suggests that ngf promotes periodontal inflammation and implicates a possible use of anti-ngf treatment in periodontitis.