Biomedical subjects

Michael P Snyder

Publications and source records attributed to Michael P Snyder.

7 recordsLinked to original sources

PubMed2026

The effect of sex and endurance exercise training on the incretin signaling pathway in 17 rat tissues.

Incretin-based pharmacotherapies, particularly glucagon-like peptide-1 (GLP-1) receptor agonists, have transformed the treatment of type 2 diabetes, with demonstrated benefits across multiple organ systems. Their success has driven the investigation of related gut-derived hormones, most prominently dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) receptor agonists, but extend to other targets with similar metabolic functions. For this class of drugs, the extent to which organ health improvements are secondary to improved systemic glycemic control versus direct tissue signaling remains unclear, partly because receptor availability across tissues is poorly annotated. We leveraged data from the Molecular Transducers of Physical Activity Consortium to annotate incretin receptor expression across 17 tissues in Fischer 344 rats and the Genotype-Tissue Expression Portal for human-level receptor expression. Furthermore, given the role of exercise in the preservation of muscle mass during weight loss, we analyzed the effects of 1, 2, 4, or 8 wk of treadmill exercise training on incretin-related signaling at the epigenetic, transcript, and protein levels. Endurance training elicited sex- and tissue-specific changes in incretin receptor expression, including downregulation of Gcgr across brown adipose, adrenal glands, and white adipose tissue (WAT). Training-induced Gipr regulation occurred in the adrenal glands, brain cortex, and hippocampus. Collectively, these findings contribute to the map of incretin receptor biology and identify exercise-responsive regulatory axes that may underlie synergistic effects of exercise and incretin-based therapies on weight management and metabolic health.NEW & NOTEWORTHY This study provides the first multiomic, multitissue description of incretin signaling receptor expression and regulation in response to endurance exercise training. We identify time point and sex-specific changes in incretin signaling across tissues, highlighting training effects on Gcgr, Gipr, and Sctr regulation in the adrenals, WAT, and brain. These findings help establish an exercise-responsive incretin signaling axis that may identify interactions from incretin-based therapies and exercise-based lifestyle interventions.

Animals↗

PubMed2025

Nanobioreactor detection of space-associated hematopoietic stem and progenitor cell aging.

Human hematopoietic stem and progenitor cell (HSPC) fitness declines following exposure to stressors that reduce survival, dormancy, telomere maintenance, and self-renewal, thereby accelerating aging. While previous National Aeronautics and Space Administration (NASA) research revealed immune dysfunction in low-earth orbit (LEO), the impact of spaceflight on human HSPC aging had not been studied. To study HSPC aging, our NASA-supported Integrated Space Stem Cell Orbital Research (ISSCOR) team developed bone marrow niche nanobioreactors with lentiviral bicistronic fluorescent, ubiquitination-based cell-cycle indicator (FUCCI2BL) reporter for real-time HSPC tracking in artificial intelligence (AI)-driven CubeLabs. In month-long International Space Station (ISS) missions (SpX-24, SpX-25, SpX-26, and SpX-27) compared with ground controls, FUCCI2BL reporter, whole-genome and transcriptome sequencing, and cytokine arrays demonstrated cell-cycle, inflammatory cytokine, mitochondrial gene, human repetitive element, and apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3 (APOBEC3) deregulation together with clonal hematopoietic mutations. Furthermore, HSPC functionally organized multi-omics aging (HSPC-FOMA) analyses revealed reduced telomere maintenance, adenosine deaminase acting on RNA1 (ADAR1) p150 self-renewal gene expression, and replating capacity indicative of space-associated HSPC aging that may limit long-duration spaceflight.

Humans↗

PubMed2025

Single-cell spatial mapping reveals alteration of tissue microenvironment during early colorectal cancer.

Familial adenomatous polyposis (FAP) is a rare, hereditary syndrome that raises the risk of developing colorectal cancer (CRC). This disease model is well suited for studying the early stages of malignant transformation. Our spatial CODEX experiments reveal that, in contrast to normal mucosa, FAP mucosa, pre-cancer polyps and colorectal cancers exhibit substantial alterations in the cell type composition and tissue microenvironment. These early alterations include: an increase in the population of cancer-associated fibroblasts (CAFs), and the inhibition of tumor infiltrated lymphocytes and cell-adhesion protein by CAFs, the transformation of memory T cells into regulatory T cells, nuclear translocation of beta-catenin from the cell membrane, a decrease in the M1:M2 macrophage ratio, a notable increase in angiogenesis events. Our studies define the early stem cell, stromal, and immune steps of colorectal cancer and may benefit early detection, and therapeutic intervention.

Co-detection by Indexing (CODEX)↗

PubMed2025

Antisense oligonucleotide depletion of CCDC146 is a broad-spectrum therapeutic strategy for ALS.

Amyotrophic lateral sclerosis (ALS) is a heritable and incurable disease defined by the degeneration of motor neurons (MNs), yet the genetics of ALS remain partially understood. Using a genomic deep learning-powered whole-genome analysis of 6,715 ALS patients, we identify four rare noncoding variants associated with patient survival, including chr7:76,009,472:C>T which is linked to a 70.6% reduction in survival. Genetic editing of this variant into iPSC-derived MNs increases CCDC146 expression and exacerbates ALS-specific phenotypes including TDP-43 mislocalization. We reveal that CCDC146 was located within the basal body of primary cilia in human MNs, and that cilia structure and function is impaired by CCDC146 overexpression but is restored by its depletion. Suppressing CCDC146 using an antisense oligonucleotide (ASO) completely rescues ALS-specific survival defects in neurons derived from both sporadic and familial patients, and it extends survival and reverses TDP-43 pathology in an aggressive ALS mouse model. Taken together, CCDC146 is a new modifier of ALS survival that acts via the primary cilia of MNs. ASO targeting of CCDC146 is a potential therapeutic approach for both sporadic and genetic forms of ALS, particularly because congenital absence of CCDC146 is well tolerated.

Journal Article↗

PubMed2025

Advancing translational exposomics: bridging genome, exposome and personalized medicine.

Understanding the interplay between genetic predisposition and environmental and lifestyle exposures is essential for advancing precision medicine and public health. The exposome, defined as the sum of all environmental exposures an individual encounters throughout their lifetime, complements genomic data by elucidating how external and internal exposure factors influence health outcomes. This treatise highlights the emerging discipline of translational exposomics that integrates exposomics and genomics, offering a comprehensive approach to decipher the complex relationships between environmental and lifestyle exposures, genetic variability, and disease phenotypes. We highlight cutting-edge methodologies, including multi-omics technologies, exposome-wide association studies (EWAS), physiology-based biokinetic modeling, and advanced bioinformatics approaches. These tools enable precise characterization of both the external and the internal exposome, facilitating the identification of biomarkers, exposure-response relationships, and disease prediction and mechanisms. We also consider the importance of addressing socio-economic, demographic, and gender disparities in environmental health research. We emphasize how exposome data can contextualize genomic variation and enhance causal inference, especially in studies of vulnerable populations and complex diseases. By showcasing concrete examples and proposing integrative platforms for translational exposomics, this work underscores the critical need to bridge genomics and exposomics to enable precision prevention, risk stratification, and public health decision-making. This integrative approach offers a new paradigm for understanding health and disease beyond genetics alone.

Humans↗

PubMed2025

Evaluation of a biomarker for amyotrophic lateral sclerosis derived from a hypomethylated DNA signature of human motor neurons.

Amyotrophic lateral sclerosis (ALS) lacks a specific biomarker, but is defined by relatively selective toxicity to motor neurons (MN). As others have highlighted, this offers an opportunity to develop a sensitive and specific biomarker based on detection of DNA released from dying MN within accessible biofluids. Here we have performed whole genome bisulfite sequencing (WGBS) of iPSC-derived MN from neurologically normal individuals. By comparing MN methylation with an atlas of tissue methylation we have derived a MN-specific signature of hypomethylated genomic regions, which accords with genes important for MN function. Through simulation we have optimised the selection of regions for biomarker detection in plasma and CSF cell-free DNA (cfDNA). However, we show that MN-derived DNA is not detectable via WGBS in plasma cfDNA. In support of our experimental finding, we show theoretically that the relative sparsity of lower MN sets a limit on the proportion of plasma cfDNA derived from MN which is below the threshold for detection via WGBS. Our findings are important for the ongoing development of ALS biomarkers. The MN-specific hypomethylated genomic regions we have derived could be usefully combined with more sensitive detection methods and perhaps with study of CSF instead of plasma. Indeed we demonstrate that neuronal-derived DNA is detectable in CSF. Our work is relevant for all diseases featuring death of rare cell-types.

Humans↗

PubMed2024

Molecular adaptations in response to exercise training are associated with tissue-specific transcriptomic and epigenomic signatures.

Regular exercise has many physical and brain health benefits, yet the molecular mechanisms mediating exercise effects across tissues remain poorly understood. Here we analyzed 400 high-quality DNA methylation, ATAC-seq, and RNA-seq datasets from eight tissues from control and endurance exercise-trained (EET) rats. Integration of baseline datasets mapped the gene location dependence of epigenetic control features and identified differing regulatory landscapes in each tissue. The transcriptional responses to 8 weeks of EET showed little overlap across tissues and predominantly comprised tissue-type enriched genes. We identified sex differences in the transcriptomic and epigenomic changes induced by EET. However, the sex-biased gene responses were linked to shared signaling pathways. We found that many G protein-coupled receptor-encoding genes are regulated by EET, suggesting a role for these receptors in mediating the molecular adaptations to training across tissues. Our findings provide new insights into the mechanisms underlying EET-induced health benefits across organs.

Animals↗