Inhibitory effects of IL-12 on experimental tooth movement and root resorption in mice.

Abstract

OBJECTIVE:

Interleukin (IL)-12 is an important cytokine for innate and adaptive immunity. We previously reported that IL-12 inhibits tumour necrosis factor (TNF)-α-mediated osteoclast formation by inducing apoptosis. We also reported that TNF-α plays an important role in mechanical loading-induced osteoclast formation and bone resorption during orthodontic tooth movement. In this study, we investigated the effects of IL-12 on mechanical tooth movement in mice.

DESIGN:

A Ni-Ti closed coil spring was inserted between the upper incisors and the upper left first molar in mice. IL-12 was injected locally adjacent to the first molar every other day during the experimental period, at doses varying from 0 to 1.5μg/day. After 12 days, the animals were killed and their jaws were processed for histological evaluation using tartrate-resistant acid phosphatase (TRAP) and TdT-mediated dUTP-biotin nick end-labelling (TUNEL) staining, and measurements of the root resorption area.

RESULTS:

In the IL-12-treated mice, tooth movement and root resorption appeared to be reduced. In TUNEL-stained sections, many apoptotic cells were recognized on the pressure side in the IL-12-treated mice.

CONCLUSIONS:

Our findings suggest that IL-12 inhibits not only mechanical tooth movement, but also root resorption during orthodontic tooth movement. These findings may arise through apoptosis induced by IL-12.

• Authors: Masako Yoshimatsu, Hideki Kitaura, Yuji Fujimura, Haruka Kohara, Yukiko Morita, Toshiko Eguchi, Noriaki Yoshida
• Journal: Archives of oral biology (Arch Oral Biol) Vol. 57 Issue 1 Pg. 36-43 (Jan 2012) ISSN: 1879-1506 [Electronic] England
• PMID: 21821230 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier Ltd. All rights reserved.

Chemical References

• Tumor Necrosis Factor-alpha
• Interleukin-12

Topics

• Animals
• Apoptosis (drug effects)
• In Situ Nick-End Labeling
• Interleukin-12 (pharmacology)
• Male
• Mice
• Mice, Inbred C57BL
• Osteoclasts (drug effects)
• Root Resorption (prevention & control)
• Stress, Mechanical
• Tooth Movement Techniques
• Tumor Necrosis Factor-alpha (pharmacology)