Effect of oral appliance on circulating leukocyte telomere length and SIRT1 in obstructive sleep apnea.

The increased cardiovascular risk seen in patients with obstructive sleep apnea (OSA) may be due to combination of oxidative stress, systemic inflammation and damage to leukocyte telomere length (LTL) seen with aging. Another molecule, Sirtuin 1 (SIRT1), a histone/protein deacetylase, regulates endothelial nitric oxide synthase and is involved in different aspects of cardiovascular disease, aging and stress resistance. The aim of this study was to evaluate the effects of mandibular advancement device (MAD) on the circulating LTL and SIRT1 protein level in peripheral blood mononuclear cells (PBMCs) in patients with OSA. Forty patients with moderately severe to severe OSA who desired MAD and 20 healthy controls were prospectively enrolled. The LTL was measured by quantitative polymerase chain reaction while SIRT1 protein levels in PBMC was assessed using a Sirtuin 1 ELISA Kit. All study subjects underwent baseline sleep study, with OSA patients having repeat testing at 3 months after MAD. Compared to healthy subjects, patients with OSA at baseline had lower LTL and SIRT1 protein levels in PBMC. After 3 months of MAD, 24 OSA patients, designated as MAD responders, median (range) LTL increased from (0.556 [0.393-0.748]) to (0.708 [0.533-0.893]) and SIRT1 protein levels in PBMC increased from 0.58 ± 0.23 pg/μg of total protein to 0.95 ± 0.26 pg/μg of total protein. For the 16 MAD unresponsive patients, LTL and SIRT1 protein levels remained low. Successful treatment of OSA with MAD can restore LTL and SIRT1 protein levels in PBMC. LTL and SIRT1 protein levels in PBMC can be improved following effective treatment of OSA using MAD.