Paradoxical sleep deprivation induces differential biological response in rat masticatory muscles: Inflammation, autophagy and myogenesis.

Background The aim of this study was to evaluate whether sleep deprivation (SD) induces inflammation, autophagy and myogenesis in the following masticatory muscles: masseter and temporal. Methods In this study, 18 animals were randomly distributed into three groups: control group (CTL, n = 6), SD for 96 hours (SD96, n = 6), and SD for 96 hours and more 96 hours of sleep recovery (SD96 + R, n = 6). Results In the histopathological analysis, SD 96 was able to induce inflammation in masseter and temporal. Nevertheless, the lack of inflammatory process was evidenced to the masseter in the group SD96 + R. Upregulation of TNF-alpha production was detected in the SD96 group, while SD96 + R decreased TNF immunoexpression for both skeletal muscles evaluated. MyoD and myogenin increased in rats submitted to SD96. By contrast, the levels of MyoD decreased in the group SD96 + R. Myogenin pointed out high immunoexpression in SD96 + R groups. In temporal, pAkt decreased in animals submitted to SD96, but it increased in the group SD96 + R. The levels of LC3 protein increased in both skeletal muscles studied, and masseter decreased LC3 protein expression in the SD96 + R. Conclusion In summary, our results demonstrate that SD is able to induce inflammation, atrophy and myogenesis in rat masticatory muscles, being more intense in temporal when compared to masseter.