Impact of Simulated Obesity in Animals on RANK/RANKL/OPG Pathway During Orthodontic Tooth Movement

Area of Science:

• Biomedical Science
• Orthodontics
• Metabolic Research

Background:

• Obesity is a growing global health concern with complex metabolic and physiological effects.
• Understanding how obesity influences tissue response to mechanical stimuli, such as orthodontic tooth movement (OTM), is crucial.
• Key molecular pathways involving Receptor Activator of Nuclear Factor κB (RANK), RANK Ligand (RANKL), and Osteoprotegerin (OPG) are implicated in bone remodeling.

Purpose of the Study:

• To investigate the effect of simulated obesity on the expression of RANK, RANKL, and OPG during OTM in a rat model.
• To determine if obesity alters the molecular response of alveolar bone to orthodontic forces.

Main Methods:

• Forty male Wistar rats were divided into non-obese and obese groups, with obesity induced by a high-fat diet for 8 weeks.
• Orthodontic force was applied to the maxillary first molar using nickel-titanium coil springs.
• Gene expression of RANK, RANKL, and OPG in alveolar bone was analyzed using qRT-PCR at 7 and 14 days post-OTM.

Main Results:

• A statistically significant difference in RANK expression was observed between non-obese and obese rats on the OTM side at 7 days (p < 0.01), but not at 14 days.
• No significant differences in RANKL and OPG gene expression were found between the groups at either 7 or 14 days of OTM.

Conclusions:

• Simulated obesity does not affect RANKL and OPG gene expression during orthodontic tooth movement in rats.
• The transient impact of obesity on RANK gene expression warrants further investigation in the context of OTM.