Abstract: The functional state of a sphingomyeline cycle and character of its mutual relations with the processes of free radical lipid oxidation during starvation of animals without any restriction of access to drinking water at 1, 2, 3 day (I phase) and 6 day (II phase of starvation) were studied at the liver of rats. The maximal values of the ceramide/sphingomyeline ratio and activity neutral sphingomyelinase and executive caspase-3 were reached in a liver of animals at the 3rd day of starvation . From the 3rd day of starvation the concentration of the tumour necrosis factor-α which is one of activators neutral sphingomyelinase was increase in rats blood serum. During the extent of large part of the I phase of starvation the intensity of free radical lipid peroxidation in a liver had almost the same level as in control group - that was a result of the high-grade functioning of antioxidant defense system. After transition the I phase of starvation into the II phase (6 day of experiment) the oxidative stress was developed as result of an exhaustion of system antioxidant defense potential in a liver. The results of this data can testify that during I phase of starvation in a liver the conditions was raised for display of the ceramide-mediated proapoptotic signalling. We assume that ceramide-mediated apoptosis is one of mechanisms of optimization of liver cellular population at the frames of metabolic adaptation. The I phase of starvation in a liver proves by the ceramide-mediated proapoptotic signaling developing. During the II phase of starvation the oxidative stress process were prevailed.
Reference: Kuzmenko D.I., Burov P.G., Serebrov V.Yu., Fait E.A., Perevozchikova T.V., Functional state of a sphingomyeline cycle and free radical lipid oxidation activity of a rat's liver during different phases of starvation, Biomeditsinskaya khimiya, 2012, vol: