Fig. 8.

Theoretical framework of possible mechanisms by which sleep fragmentation and recurrent nocturnal arousals might contribute to the occurrence of metabolic syndrome. Two key features of OSAS, namely, sleep fragmentation and recurrent nocturnal arousal, could lead to increased sympathetic nerve activity and altered glucose metabolism in skeletal muscle. ROS production in fat and activation of inflammatory pathways lead to the increased release of inflammatory factors and changes in fat-related factors, leading to metabolic dysfunction and impaired islet function. In addition, elevated SREBPs and decreased lipase caused by inflammation and oxidative stress lead to associated lipid/lipoprotein abnormalities