Project description:Aging is the predominant cause of morbidity and mortality in industrialized countries. The specific molecular mechanisms that drive aging are poorly understood, especially the contribution of the microbiota in these processes. Here, we combined multi-omics with metabolic modeling in mice to comprehensively characterize host–microbiome interactions and how they are affected by aging. Our findings reveal a complex dependency of host metabolism on microbial functions, including previously known as well as novel interactions. We observed a pronounced reduction in metabolic activity within the aging microbiome, which we attribute to reduced beneficial interactions in the microbial community and a reduction in the metabolic output of the microbiome. These microbial changes coincided with a corresponding downregulation of key host pathways predicted by our model that are crucial for maintaining intestinal barrier function, cellular replication, and homeostasis. Our results elucidate potential microbiome–host interactions that may influence host aging processes, focusing on microbial nucleotide metabolism as a pivotal factor in aging dynamics.
Project description:Aging is the predominant cause of morbidity and mortality in industrialized countries, yet the molecular mechanisms driving aging and especially the contribution by the microbiome remain unclear. We combined multi-omics with metabolic modeling to comprehensively characterize host–microbiome interactions during aging in mice. Our findings reveal a complex dependency of host metabolism on known and novel microbial interactions. We observed a pronounced reduction in metabolic activity within the aging microbiome accompanied by reduced beneficial interactions between bacterial species. These microbial changes coincided with increased inflammaging as well as a corresponding downregulation of key host pathways, predicted by our model to be microbiome-dependent, that are crucial for maintaining intestinal barrier function, cellular replication, and homeostasis. Our results elucidate microbiome–host interactions that potentially influence host aging processes, focusing on microbial nucleotide metabolism as a pivotal factor in aging dynamics. These pathways could serve as future targets for the development of microbiome-based anti-aging therapies.
Project description:Chronic Kidney Disease (CKD), a global health burden, is strongly associated with age-related renal function decline, hypertension and diabetes, frequent consequences of obesity. Despite extensive studies the mechanisms determining susceptibility to CKD remain elusive. Clinical evidence together with prior studies from our group showed that perinatal metabolic disorders after maternal obesity adversely affect kidney structure and function throughout life. Since obesity and aging processes converge in similar pathways we tested if perinatal obesity induced by High-Fat Diet (HFD)-fed female mice sensitizes aging-associated mechanism in kidneys of newborn mice. Tissue from the kidney cortex and the kidney medulla was collected from offspring of control or HFD-fed mice.
Project description:Decline in tissue NAD levels during aging has been linked to aging-associated diseases, such as age-related metabolic disease, physical decline, and Alzheimers disease. However, the mechanism for aging-associated NAD decline remains unclear. Here we report that pro-inflammatory M1 macrophages, but not naive or M2 macrophages, highly express the NAD consuming enzyme CD38 and have enhanced CD38-dependent NADase activity. Furthermore, we show that aging is associated with enhanced inflammation due to increased senescent cells, and the accumulation of CD38 positive M1 macrophages in visceral white adipose tissue. We also find that inflammatory cytokines found in the supernatant from senescent cells (Senescence associated secretory proteins, SASP) induces macrophages to proliferate and express CD38. As senescent cells progressively accumulate in adipose tissue during aging, these results highlight a new causal link between visceral tissue senescence and tissue NAD decline during aging and may present a novel therapeutic opportunity to maintain NAD levels during aging.
Project description:Skeletal muscle aging is characterized by a progressive decline in muscle mass and function, which is referred to as sarcopenia. Aging is also a primary risk factor for metabolic syndrome (SX), which is a cluster of risk factors for cardiovascular diseases and type 2 diabetes. However, the molecular mechanisms implicated in sarcopenia and changes in muscle proteome associated with SX in elderly men remain unclear. In this dataset, we include the expression data obtained from vastus lateralis muscle biopsies of young and old men with or without metabolic syndrome. These data are used to identify 479 genes that are differentially expressed with aging, 328 being associated with aging alone and 117 with metabolic syndrome.
Project description:Aging-associated functional decline and disease susceptibility are believed to be mediated, at least in part, through alterations in the epigenome. To explore epigenetic changes that might influence visual function with advanced age, we performed whole genome bisulfite sequencing of purified mouse rod photoreceptors at four different ages and identified 2054 genomic regions that gain or lose DNA methylation. Differentially methylated regions (DMRs) clustered at chromosomal hotspots, especially on Chromosome 10 that included a longevity interactome. DMRs were preferentially detected at an early stage of aging in long neuronal genes and in rod-specific regulatory regions containing open chromatin domains and H3K27 acetylation. Integration of methylome to age-related transcriptome changes, chromatin signatures and first order protein-protein interactions uncovered an enrichment of DMRs in pathways associated with aging, longevity, synaptic function, and energy homeostasis. In concordance, we detected reduced mitochondrial maximum reserve capacity with retinal age in ex vivo assays. Our study reveals age-dependent genomic and chromatin features susceptible to DNA methylation changes in rod photoreceptors and identifies associations with established and cell type-specific pathways altered in aging.
Project description:Aging of the vasculature is associated with detrimental changes in vascular smooth muscle cell (VSMC) mechanosensitivity to extrinsic forces in their surrounding microenvironment. However, how chronological aging alters VSMCs’ ability to sense and adapt to mechanical perturbations remains unexplored. Here, we show defective VSMC mechanosensation in aging measured with ultrasound tweezers-based micromechanical system, force instantaneous frequency spectrum and transcriptome analyses. The mechanobiological study reveals thataged VSMCs adapt a relatively inert solid-like state with altered actin cytoskeletal integrity, resulting in an impairment in their mechanosensitivity and dynamic mechanoresponse to mechanical perturbations. The aging-associated decline in mechanosensation behaviors is mediated by hyperactivity of Piezo1-dependent calcium signaling. Inhibition of Piezo1 alleviates vascular aging and partially restores the loss in dynamic contractile properties in aged cells. Altogether, our study reveals the novel signaling pathway underlying aging-associated aberrant mechanosensation in VSMC and identifies Piezo1 as a potential therapeutic mechanobiological target to alleviate vascular aging.
Project description:Aging-associated functional decline and disease susceptibility are believed to be mediated, at least in part, through alterations in the epigenome. To explore epigenetic changes that might influence visual function with advanced age, we performed whole genome bisulfite sequencing of purified mouse rod photoreceptors at four different ages and identified 2054 genomic regions that gain or lose DNA methylation. Differentially methylated regions (DMRs) clustered at chromosomal hotspots, especially on Chromosome 10 that included a longevity interactome. DMRs were preferentially detected at an early stage of aging in long neuronal genes and in rod-specific regulatory regions containing open chromatin domains and H3K27 acetylation. Integration of methylome to age-related transcriptome changes, chromatin signatures and first order protein-protein interactions uncovered an enrichment of DMRs in pathways associated with aging, longevity, synaptic function, and energy homeostasis. In concordance, we detected reduced mitochondrial maximum reserve capacity with retinal age in ex vivo assays. Our study reveals age-dependent genomic and chromatin features susceptible to DNA methylation changes in rod photoreceptors and identifies associations with established and cell type-specific pathways altered in aging.