Project description:We conducted an extensive study involving the collection of 41 mouse organs at eight distinct time points spanning the mouse lifespan and implemented a dietary intervention with varying protein intake for different age and sex groups. We also obtained plasma samples from both mice and humans to investigate the systemic effects of aging and PR.
Project description:We conducted an extensive study involving the collection of 41 mouse organs at eight distinct time points spanning the mouse lifespan and implemented a dietary intervention with varying protein intake for different age and sex groups. We also obtained plasma samples from both mice and humans to investigate the systemic effects of aging and PR.
Project description:Calorie restriction (CR) extends lifespan by modulating the mechanisms involved in aging. We quantified the hepatic proteome of male C57BL/6 mice exposed to graded levels of CR (0% to 40% CR) for three months, and evaluated which signaling pathways were most affected.
Project description:Gestational protein restriction is a model for low birth size. We hypothesized that taurine supplementation would protect against changes in newborn liver and muscle caused by a maternal low protein diet. Pregnant mouse dams were subjected to different diet schemes from day 1 of pregnancy until birth. Pups were killed following birth and liver and hindleg skeletal muscle taken out and frozen at -80C until analysis. Diet schemes: Normal Protein (20% casein; NP), Normal Protein + taurine (1% taurine supplementation in water ad libitum; NP+tau), Low Protein (8% casein; LP) and LP+tau The liver and muscle samples were normalized separately.
Project description:Gestational protein restriction is a model for low birth size. We hypothesized that taurine supplementation would protect against changes in newborn liver and muscle caused by a maternal low protein diet.
Project description:We found that low protein diet consumption resulted in decrease in the percentage of normal Paneth cell population in wild type mice, indicating that low protein diet could negatively affect Paneth cell function. We performed fecal microbiota composition profiling. Male mice were used at 4-5 weeks of age. Fecal samples were collected for microbiome analysis.
Project description:Calorie restriction (CR) enhances longevity and mitigates aging phenotypes in numerous species. Physiological responses to CR are cell-type specific and variable throughout the lifespan; however, the mosaic of molecular changes responsible CR benefits remain unclear, particularly in brain regions susceptible to deterioration throughout aging. Thus, we examined the influence of long-term CR on the CA1 hippocampal region, a key learning and memory brain area that is vulnerable to age-related pathologies, such as Alzheimerâs disease (AD). Through mRNA sequencing and NanoString nCounter analysis, we demonstrate that one year of CR feeding suppresses an age-dependent signature of 882 genes functionally associated with synaptic transmission-related pathways, including calcium signaling, long-term potentiation (LTP), and Creb signaling in wild-type mice. By comparing the influence of CR on hippocampal CA1 region transcriptional profiles at younger- (5 months) and older-adult (15 months) timepoints, we identify conserved upregulation of proteome quality control and calcium buffering genes, including heat shock 70 kDa proteins 1b and 5 (Hspa1b and Hspa5), protein disulfide isomerase family A members 4 and 6 (Pdia4 and Pdia6), and calreticulin (Calr). Expression levels of putative neuroprotective factors, klotho (Kl) and transthyretin (Ttr), are also elevated by CR throughout adulthood, although the global CR-specific expression profiles at young and older timepoints are highly divergent. At a previously unachieved resolution, our results demonstrate conserved activation of neuroprotective gene signatures and broad CR-suppression of age-dependent hippocampal CA1 region expression changes, indicating that CR functionally maintains a more youthful transcriptional state within hippocampal CA1 throughout aging. Hippocampal CA1 region mRNA profiles of younger- (5 months) and older-adult (15 months) mice on calorie-restricted (CR) and normal (AD) diets were generated by deep sequencing using Illumina HiSeq 2500.
Project description:Background: Environmental influences fluctuate throughout the life course of an organism. It is therefore important to understand how the timing of exposure impacts the molecular response. Here we examine the responses of two key molecular markers of dietary stress – variant-specific methylation at ribosomal DNA (rDNA) and small RNA distribution including tRNA fragments – in a mouse model of protein restriction (PR) with exposures pre- and/or post-weaning. Results: We first confirm that pre-weaning PR exposure modulates the methylation state of rDNA in a genotype-dependent manner whereas post-weaning PR exposure has no such effect. Conversely, post-weaning PR induces a shift in small RNA distribution, but there is no effect in the pre-weaning PR model. Intriguingly, mice exposed to PR throughout their lives show neither of these two dietary stress markers, similar to controls.