2022, Vol. 26 ›› Issue (35): 5626-5632

Effect of mandibular advancement device on mitochondrial ultrastructure of the genioglossus in the treatment of obstructive sleep apnea

Yuan Xixi1, Zhao Zirui1, Zhang Yanyan1, Huang Yu1, Shi Kaikai1, Fan Dengying2, Zhu Yahui2, Liu Chunyan2   

Abstract: BACKGROUND: At present, the common treatment method for obstructive sleep apnea is mandibular advancement device. Scholars have reached a consensus that the abnormality of the genioglossus muscle can cause obstructive sleep apnea. However, insufficient attention has been paid to the mechanism that causes genioglossus muscle damage and dysfunction and the impact of relevant treatment methods on the genioglossus muscle.
OBJECTIVE: To evaluate the effects of mandibular advancement device for obstructive sleep apnea on the genioglossus ultrastructure and explore whether oxidative stress pathway is the mechanism of obstructive sleep apnea causing skeletal muscle structure and function disorders.
METHODS: Thirty rabbits were divided into three groups: control, obstructive sleep apnea, and mandibular advancement device groups. Rabbit models of obstructive sleep apnea were established in the latter two groups. Three days after modeling, all rabbits were induced to sleep in supine position. CT scans were performed to examine the changes in upper airway structure and polysomnography was used to monitor changes in blood oxygen saturation and respiratory sleep index. After 8 weeks, the ultrastructure of the genioglossus muscle was detected under transmission electron microscope. The level of malondialdehyde in the genioglossus muscle was measured by the thiobarbituric acid method, and the levels of 8-isoprostaglandin in the plasma and genioglossus muscle were measured by the enzyme-linked immunosorbent assay method. The level of glutathione and activities of catalase, total superoxide dismutase, copper-zinc superoxide dismutase, manganese superoxide dismutase, and succinate dehydrogenase were measured in strict accordance with the kit instructions.
RESULTS AND CONCLUSION: The morphology and structure of genioglossus mitochondria were normal in the control group, and were seriously damaged in the obstructive sleep apnea group. Compared with the control group, the obstructive sleep apnea group had a higher level of   8-isoprostaglandin (P < 0.05); the level of malondialdehyde was increased significantly in the obstructive sleep apnea group compared with the other two groups (P < 0.05); the activities of total superoxide dismutase, copper-zinc superoxide dismutase and manganese superoxide dismutase decreased significantly in the obstructive sleep apnea group compared with the other two groups (P < 0.05); glutathione level and the activities of catalase and succinate dehydrogenase decreased significantly in the obstructive sleep apnea group compared with the control group (P < 0.05). However, there were no significant differeces between mandibular advancement device group and control group (P < 0.05). To conclude, obstructive sleep apnea -induced genioglossus mitochondria damage is related to oxidative stress. Mandibular advancement device can prevent or alleviate the damage of mitochondrial structure caused by obstructive sleep apnea.
Key words: mandibular advancement device, obstructive sleep apnea, genioglossus, mitochondrial structure, oxidative stress, glutathione, catalase, superoxide dismutase, succinate dehydrogenase