Project description:Brain-specific SIRT6-KO mice present increased DNA damage, learning impairments, and neurodegenerative phenotypes, placing SIRT6 as a key protein in preventing neurodegeneration. In the aging brain, SIRT6 levels/activity decline, which is accentuated in Alzheimer's patients. To understand SIRT6 roles in transcript pattern changes, we analyzed transcriptomes of young WT, old WT and young SIRT6-KO mice brains, and found changes in gene expression related to healthy and pathological aging. In addition, we traced these differences in human and mouse samples of Alzheimer's and Parkinson's diseases, healthy aging and calorie restriction (CR). Our results define four gene expression categories that change with age in a pathological or non-pathological manner, which are either reversed or not by CR. We found that each of these gene expression categories is associated with specific transcription factors, thus serving as potential candidates for their category-specific regulation. One of these candidates is YY1, which we found to act together with SIRT6 regulating specific processes. We thus argue that SIRT6 has a pivotal role in preventing age-related transcriptional changes in brains. Therefore, reduced SIRT6 activity may drive pathological age-related gene expression signatures in the brain.
Project description:Microarray analysis of liver tissue from WT SIRT6 and conditional knockout of SIRT6 using albumin-Cre (SIRT6Co/Co ;Alb-Cre) at 2 and 8 months of age RNA was extracted from mouse liver tissue at 2 and 8 months of age. RNA from three pairs of WT SIRT6 and SIRT6Co/Co ;Alb-Cre mice was combined and hybridized to Affymetrix mouse gene 1.0 ST arrays.
Project description:Our previous data had suggested that gluconeogenesis capacity from the precursors lactate and glycerol declines in old C57BL/6 mice. This decline was rescued by whole body SIRT6 overexpression. Since the liver is the main gluconeogenic organ, we performed here liver metabolomics in young (6 months) versus old (20-24 months) WT and SIRT6-transgenic mice. We used liver tissues of 6h morning-fasted mice, either in naïve state or 15 minutes after intraperitoneal injection of 1mg/kg [U-13C]Lactate.
Project description:Brains are sexually dimorphic in adult zebrafish. We dissected brains from young and old, adult zebrafish, from both males and females. Brains are not pooled but analyzed as indivual samples.
Project description:Microarray analysis of liver tissue from WT SIRT6 and conditional knockout of SIRT6 using albumin-Cre (SIRT6Co/Co ;Alb-Cre) at 2 and 8 months of age
Project description:Brains are sexually dimorphic in adult zebrafish. We dissected brains from young and old, adult zebrafish, from both males and females. Brains are not pooled but analyzed as indivual samples. Four groups of wild-type zebrafish (AB strain) were used for this study: young (7.5-8.5 months old) male and female and old (31-36 months old) male and female. There were three animals per group for a total of 12 animals in the study.
Project description:The adaptor protein Lnk is an important negative regulator of HSC homeostasis and self-renewal. This study aims to investigate the role of Lnk in HSC aging. Here we performed expression profiling of bone marrow CD150+CD48-LSK LT-HSCs from young and old WT and Lnk-/- mice. Results identify select Lnk-mediated pathways with potential involvement in HSC self-renewal and aging.