Investigation of the hepatic mTOR/S6K1/SREBP1 signalling pathway in rats at different ages: from neonates to adults.

Background Dysfunctions in the lipogenic process controlled by the hepatic mTOR/S6K1/SREBP-1c signaling pathway may contribute to the pathogenesis of various chronic diseases. In the present study, we aimed to determine age-related changes in the mTOR/S6K1/SREBP1 pathway in rat liver tissues. Methods and results We performed Western Blot analysis to determine age-related changes in the mTOR/S6K1/SREBP1 pathway in Sprague Dawley male rats liver tissues of six different age groups representing neonatal, infant, weaning, puberty, young adult, adult life periods, and Oil Red O staining to evaluate age-related lipid accumulation. We observed an increase in Akt and p-Akt levels with age in compared to the 0-day-old group. Total mTOR and SREBP1 expression increased from the 0-day-old to the 28-day-old group but decreased in the following age groups. p-mTOR and p-S6K1 levels in the 0-day-old group were higher than the other groups. S6K1 expression was lowest in the 0-day-old group and showed changes among the age groups. Lipid accumulation was seen in liver sections taken from the 12-month-old group. mTOR/S6K1/SREBP1 pathway expression showed changes with age during the neonatal-adult life cycle stages in rat liver tissues. Conclusion We suggest that understanding the molecular mechanisms age-related changes of lipogenesis function is necessary to contribute to the development of therapeutic approaches.