The flower pot method of REM sleep deprivation causes apoptotic cell death in the hepatocytes of rat

Introduction The rapid eye movement sleep deprivation (REMSD) of rats relates with increased inflammations, acute phase response, oxidative damage, neuronal cell loss, and neurodegenerative diseases. Whereas, its role outside brain are not well studied. This study tried to explore the causal effect of REM sleep loss on hepatocytes. Methods We deprived the rats of REM sleep using standard flower pot method. We focused on liver to see the REMSD affects which controls most of the metabolic processes of the body. Results We report here that flower pot induced REMSD causes apoptotic cell death of hepatocytes (~10% by Annexin Assay & ~20% by TUNEL assay). This were further got alleviated up to extent after sleep recovery of 5 days (recovered approximately 8.0% by Annexin Assay & 14% by TUNEL assay). The gene expression and protein level profiling revealed the up-regulation of p53, Bax, Cytochrome c, Caspase 3, and Caspase 9. While, Bcl2 which is an anti-apoptotic protein were down-regulated in response to REMSD. Relentless recovery of 5 days affected the expression pattern of these genes/proteins. Conclusions Our study offer great pathological and physiological significance for sleep loss, by inferring the apoptotic cell-death in the hepatocytes of rat. This further signifies the functional and preventive role of REM sleep which is unique to mammals and avians with certain exceptions, as its loss can affect the natural well-being and survival of the individuals. Highlights of the study We observed significant apoptosis in the hepatocytes of REMSD group of rats. Our expression analysis confirmed altered expression for genes p53, Bcl2, Bax, and Caspase-3 after REMSD. Protein level analysis supported our gene expression results for p53, Bcl2, Bax, Caspase 3 and Caspase 9 after REMSD. Sleep recovery improved the respective genes and protein expression levels towards normalcy, signifying the functional role of REM sleep.