Mandibular Advancement Device Improves the Function of Hypoglossal Nerve in OSA Rabbits

Area of Science:

• Neurology
• Sleep Medicine
• Biomedical Engineering

Background:

• Obstructive sleep apnea (OSA) is linked to hypoglossal nerve and genioglossus motor endplate dysfunction.
• The precise mechanisms underlying OSA-induced neurological damage remain incompletely understood.
• Mandibular advancement devices (MAD) are a common treatment for OSA, but their neuroprotective effects require further investigation.

Purpose of the Study:

• To investigate the interaction between the genioglossus motor endplate and the hypoglossal nerve in an OSA model.
• To explore the therapeutic mechanism of MAD in treating OSA at the neuromuscular junction level.

Main Methods:

• An OSA rabbit model was established by soft palate injection, with a MAD treatment group and a control group.
• Cone-beam computed tomography (CBCT) and polysomnography (PSG) were used to confirm OSA induction and MAD efficacy.
• Electrophysiology, nerve fiber morphology, motor endplate assessment, and immunofluorescence staining were employed to evaluate nerve conduction and structural integrity.

Main Results:

• OSA induction led to structural and functional impairments in the hypoglossal nerve and genioglossus motor endplates.
• MAD treatment successfully reversed OSA symptoms and alleviated the observed neuromuscular damage.
• Nerve impulse conduction and genioglossus muscle function were significantly improved following MAD therapy.

Conclusions:

• MAD treatment effectively mitigates OSA-induced damage to the hypoglossal nerve and genioglossus motor endplates.
• MAD therapy enhances the structure and function of the neuromuscular junction in OSA patients.
• This study provides mechanistic insights into how MAD improves OSA by protecting the hypoglossal nerve and related musculature.