Selected Grantee Publications
- Clear All
- 41 results found
- Rodent Models
- Neurological
- Stem Cells/Regenerative Medicine
Multimodal Analysis of Dysregulated Heme Metabolism, Hypoxic Signaling, and Stress Erythropoiesis in Down Syndrome
Donovan et al., Cell Reports. 2024.
https://pubmed.ncbi.nlm.nih.gov/39120971
Down syndrome (DS), a genetic condition caused by the presence of an extra copy of chromosome 21, is characterized by intellectual and developmental disability. Infants with DS often suffer from low oxygen saturation, and DS is associated with obstructive sleep apnea. Investigators assessed the role that hypoxia plays in driving health conditions that are comorbid with DS. A multiomic analysis showed that people with DS exhibit elevated heme metabolism and activated stress erythropoiesis, which are indicators of chronic hypoxia; these results were recapitulated in a mouse model for DS. This study identified hypoxia as a possible mechanism underlying several conditions that co-occur with DS, including congenital heart defects, seizure disorders, autoimmune disorders, several leukemias, and Alzheimer's disease. Supported by ORIP (R24OD035579), NCATS, NCI, and NIAID.
Transcriptomic Analysis of Skeletal Muscle Regeneration Across Mouse Lifespan Identifies Altered Stem Cell States
Walter et al., Nature Aging. 2024.
https://pubmed.ncbi.nlm.nih.gov/39578558
Age-related skeletal muscle regeneration dysfunction is poorly understood. Using single-cell transcriptomics and high-resolution spatial transcriptomics, researchers evaluated factors contributing to age-related decline in skeletal muscle regeneration after injury in young, old, and geriatric male and female mice (5, 20, and 26 months old). Eight immune cell types were identified and associated with age-related dynamics and distinct muscle stem cell states specific to old and geriatric tissue. The findings emphasize the role of extrinsic and intrinsic factors, including cellular senescence, in disrupting muscle repair. This study provides a spatial and molecular framework for understanding regenerative decline and cellular heterogeneity in aging skeletal muscle. Supported by ORIP (F30OD032097), NIA, NIAID, NIAMS, NICHD, and NIDA.
Impaired Axon Initial Segment Structure and Function in a Model of ARHGEF9 Developmental and Epileptic Encephalopathy
Wang et al., PNAS. 2024.
https://www.pnas.org/doi/10.1073/pnas.2400709121
Researchers developed a mouse model carrying the G55A missense variant identified in ARHGEF9 patients with severe epilepsy and neurodevelopmental phenotypes. Using male Arhgef9G55A mice, this study examined behavioral, molecular, and electrophysiological phenotypes in the Arhgef9G55A model of developmental and epileptic encephalopathies (DEE). Researchers found that the G55A variant causes disruption of inhibitory postsynaptic organization and axon initial segment (AIS) architecture, leading to impairment of both synaptic transmission and action potential generation. The effects of Arhgef9G55A on neuronal function affect both intrinsic and synaptic excitability and preferentially impair AIS. These findings indicate a novel pathological mechanism of DEE and represent a unique example of a neuropathological condition converging from AIS dysfunctions. Supported by ORIP (U54OD020351, U54OD030187, U54OD020351, S10OD026974) and NINDS.
The Role of ATP Citrate Lyase in Myelin Formation and Maintenance
Schneider et al., Glia. 2024.
https://pubmed.ncbi.nlm.nih.gov/39318247/
Myelin formation by Schwann cells is critical for peripheral nervous system development and long-term neuronal function. The study examined how acetyl coenzyme A (acetyl-CoA), essential for lipid synthesis in myelin, is derived, with a focus on mitochondrial ATP citrate lysate (ACLY). By using both sexes in a Schwann cell–specific ACLY knockout mouse model, the authors reported that ACLY plays a role in acetyl-CoA supply for myelin maintenance but not myelin formation. ACLY is necessary for sustaining myelin gene expression and preventing nerve injury pathways. This work highlights a unique dependency on mitochondrial acetyl-CoA for Schwann cell integrity, providing insights into lipid metabolism in neuronal repair. Supported by ORIP (T35OD011078), NICHD, and NINDS.
Bone Marrow Transplantation Increases Sulfatase Activity in Somatic Tissues in a Multiple Sulfatase Deficiency Mouse Model
Presa et al., Communications Medicine. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11502872/pdf/43856_2024_Article_648.pdf
Multiple Sulfatase Deficiency (MSD) is a rare genetic disorder where patients demonstrate loss of function mutations in the SUMF1 gene, resulting in a severe reduction in sulfatase activity. This enzyme deficiency causes impaired lysosomal function and widespread inflammation, leading to clinical manifestations like neurodegeneration, vision and hearing loss, and cardiac disease. The researchers evaluated the therapeutic potential of hematopoietic stem cell transplant (HSCT) to initiate cross-correction, where functional sulfatase enzymes secreted from the healthy donor cells are taken up to restore function in enzyme-deficient host cells. Bone marrow from healthy male and female B6-Sumf1(+/+) mice were transplanted into B6-Sumf1(S153P/S153P) mice, a model for MSD. The results showed that HSCT is suitable to rescue sulfatase activity in peripheral organs, such as the liver, spleen, and heart, but is not beneficial alone in inhibiting the central nervous system pathology of MSD. Supported by ORIP (U54OD020351, U54OD030187, U42OD010921) and NCI.
Commentary: The International Mouse Phenotyping Consortium: High-Throughput In Vivo Functional Annotation of the Mammalian Genome
Lloyd, Mammalian Genome. 2024.
https://pubmed.ncbi.nlm.nih.gov/39254744
The International Mouse Phenotyping Consortium (IMPC), a collectively governed consortium of 21 academic research institutions across 15 countries on 5 continents, represents a groundbreaking approach in genetics and biomedical research. Its goal is to create a comprehensive catalog of mammalian gene function that is freely available and equally accessible to the global research community. So far, the IMPC has uncovered the function of thousands of genes about which little was previously known. By 2027, when the current round of funding expires, the IMPC will have produced and phenotyped nearly 12,000 knockout mouse lines representing approximately 60% of the human orthologous genome in mice. This new knowledge has produced numerous insights about the role of genes in health and disease, including informing the genetic basis of rare diseases and positing gene product influences on common diseases. However, as IMPC nears the end of the current funding cycle, its path forward remains unclear. Supported by ORIP (UM1OD023221).
The Mutant Mouse Resource and Research Center (MMRRC) Consortium: The U.S.-Based Public Mouse Repository System
Agca et al., Mammalian Genome. 2024.
https://link.springer.com/article/10.1007/s00335-024-10070-3
The MMRRC has been the nation’s preeminent public repository and distribution archive of mutant mouse models for 25 years. The Consortium, with support from NIH, facilitates biomedical research by identifying, acquiring, evaluating, characterizing, preserving, and distributing a variety of mutant mouse strains to investigators around the world. Since its inception, the MMRRC has fulfilled more than 20,000 orders from 13,651 scientists at 8,441 institutions worldwide. Today, the MMRRC maintains an archive of mice, cryopreserved embryos and sperm, embryonic stem-cell lines, and murine monoclonal antibodies for nearly 65,000 alleles. The Consortium also provides scientific consultation, technical assistance, genetic assays, microbiome analysis, analytical phenotyping, pathology, husbandry, breeding and colony management, and more. Supported by ORIP (U42OD010918, U42OD010924, U42OD010983).
Intrinsic Link Between PGRN and GBA1 D409V Mutation Dosage in Potentiating Gaucher Disease
Lin et al., Human Molecular Genetics. 2024.
https://doi.org/10.1093/hmg/ddae113
Gaucher disease (GD) is an autosomal recessive disorder and one of the most common lysosomal storage diseases. GD is caused by mutations in the GBA1 gene that encodes glucocerebrosidase (GCase), a lysosomal protein involved in glyocolipid metabolism. Progranulin (PGRN, encoded by GRN) is a modifier of GCase, and GRN mutant mice exhibit a GD-like phenotype. The researchers in this study aimed to understand the relationship between GCase and PGRN. They generated a panel of mice with various doses of the GBA1 D409V mutation in the GRN-/- background and characterized the animals’ disease progression using biochemical, pathological, transcriptomic, and neurobehavioral analyses. Homozygous (GRN-/-, GBA1 D409V/D409V) and hemizygous (GRN-/-, GBA1 D409V/null) animals exhibited profound inflammation and neurodegeneration compared to PG96 wild-type mice. Compared to homozygous mice, hemizygous mice showed more profound phenotypes (e.g., earlier onset, increased tissue fibrosis, shorter life span). These findings offer insights into GD pathogenesis and indicate that GD severity is affected by GBA1 D409V dosage and the presence of PGRN. Supported by ORIP (R21OD033660) and NINDS.
Integrin αvβ3 Upregulation in Response to Nutrient Stress Promotes Lung Cancer Cell Metabolic Plasticity
Nam, Cancer Research. 2024.
https://pubmed.ncbi.nlm.nih.gov/38588407/
Tumor-initiating cells can survive in harsh environments via stress tolerance and metabolic flexibility; studies on this topic can yield new targets for cancer therapy. Using cultured cells and live human surgical biopsies of non-small cell lung cancer, researchers demonstrated that nutrient stress drives a metabolic reprogramming cascade that allows tumor cells to thrive despite a nutrient-limiting environment. This cascade results from upregulation of integrin αvβ3, a cancer stem cell marker. In mice, pharmacological or genetic targeting prevented lung cancer cells from evading the effects of nutrient stress, thus blocking tumor initiation. This work suggests that this molecular pathway leads to cancer stem cell reprogramming and could be linked to metabolic flexibility and tumor initiation. Supported by ORIP (K01OD030513), NCI, NIGMS, and NINDS.
CDK4/6 Inhibition Sensitizes Intracranial Tumors to PD-1 Blockade in Preclinical Models of Brain Metastasis
Nayyer et al., Clinical Cancer Research. 2024.
Brain metastases are associated with high morbidity and are often resistant to immune checkpoint inhibitors. In this study, investigators evaluated the efficacy of combining CDKi (abemaciclib) and anti–PD-1 therapy (“combination therapy”) in mouse models for brain metastases, elucidated how combination therapy remodeled the tumor–immune microenvironment (TIME) and T-cell receptor (TCR) repertoires, and investigated the effects of CDKi on T-cell development and maintenance in NOD-scid Il2rgnull (NSG) mice engrafted with human immune systems (“humanized mice”). Results offer a strong rationale for the clinical evaluation of combination CDKi and PD-1 blockade in patients with brain metastases. Supported by ORIP (R24OD026440), NCI, and NIAID.