Exploring Chromosomal Instability and Cellular Phenotypes in Ring Chromosome 14 Syndrome

Awardee: Matthew Tegtmeyer

Institution: Purdue University

Grant Amount: $60,840.00

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

We will explore whether various culture maintenance conditions can promote the stability of ring 14 in patient reprogrammed iPSCs.

Characterization of seizures in a new mouse model of KCNT1 G288S

Awardee: Jill Silverman

Institution: UC Davis

Grant Amount: $68,667

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

KCNT1-related epilepsy is an autosomal dominant NDD, resulting from de novo pathogenic variants in the sodium activated potassium channel, and are associated with Epilepsy of Infancy with Migrating Focal Seizures (EIMFS), and Autosomal Dominant Nocturnal Frontal Lobe Epilepsy (ADNFLE), characterized by clusters of nocturnal motor seizures. Few animal models exist that carry any of the 64 known human variants described, to date. To that end, we will focus our proposed studies on a novel mouse model of the human gene variant G288S (corresponding to mouse Kcnt1 G269S), a mutation located within the sequence coding for the channel pore. This mouse model has substantial translational potential because we will investigate the impact of early life seizure on occurrence, recurrence, and severity of seizure phenotypes across the lifespan to aged adults, and severity and neuro and respiratory physiological phenotypes.

Molecular Pathogenesis and Epigenetic Rescue of Novel Human Models of ZC4H2-associated rare disorders.

Awardee: Julian Halmai

Institution: UC Davis

Grant Amount: $54,187

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

The main objectives of this project are to establish human models of three unique loss of function ZARD variants within control sex-matched IMR90 NSC, using gene editing and to characterize the cellular and molecular phenotypes associated with ZARD pathology, with interest in understanding the link between ZC4H2 loss of function and BMP-Smad signaling pathway dysregulation. This proposal, if successful with shed light onto ZARD related pathology and the potential targets for therapeutic intervention.

CROSS-TISSUE ULTRASTRUCTURAL IMAGING FOR DISCOVERING FIBROTIC DETERMINANTS AND ACTIONABLE TARGETS IN DC/TBD

Awardee: Alfredo Rodríguez

Institution: National Autonomous University of Mexico (UNAM)

Grant Amount: $62,158

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

Fibrosis of the lung and liver are threatening complications for patients with DC/TBD, however the composition of the fibrotic niche and potential targets for treating and preventing it are virtually unknown. In this proposal we have assembled an international team from Mexico (UNAM) and the USA (Mayo Clinic) that will examine the composition of the fibrotic niche. Using high precision microscopy, we will generate multidimensional images of primary fibrotic lung and liver from patients with DC/TBD and using computational tools we will reconstruct the fibrotic niche in these tissues, importantly without tissue dissociation and maintaining its architecture. We will use markers for detecting multiple cell types, including pro-fibrotic immune cells, followed by state-of-the-art spatial transcriptomics using Xenium technology. Our combined approach will provide an unprecedented single cell resolution of the DC/TBD critical fibrotic tissues and will help us propose actionable targets for preventing and treating fibrosis.

Charting WDR45-dependent genes for neurodegeneration at a single-cell resolution

Awardee: Young Ah Seo

Institution: Regents of the University of Michigan

Grant Amount: $75,815.00

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

BPAN (β-propeller protein-associated neurodegeneration) is a rare neurodegenerative disorder caused by mutations in the WDR45 gene, often leading to progressive brain damage and abnormal iron buildup in the brain. Unfortunately, no cure exists for BPAN, and current treatments only manage symptoms. Our research focuses on uncovering the underlying causes of neurodegeneration in BPAN. Using a mouse model where the WDR45 gene has been deleted, we will employ single-cell RNA sequencing (scRNA-seq) to analyze changes in gene expression at the individual cell level. This will help us identify the specific brain cells and molecular pathways most affected by WDR45 loss. By mapping these pathways, we aim to pinpoint new targets for potential therapies that could prevent or slow down the progression of BPAN. This project could pave the way for developing treatments that address the root causes of BPAN, benefiting patients with this rare condition.

Short-interfering RNA to reduce heparan sulfate in Sanfilippo B syndrome

Awardee: Patricia Dickson

Institution: Washington University in St. Louis

Grant Amount: $60,000

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

This is a proposal to use ribonucleic acid (RNA) interference to reduce the production of heparan sulfate in the brain for Sanfilippo syndrome. Substrate reduction therapy aims to reduce the amount of substrate, or material, that cannot be broken down by the body. In Sanfilippo, the substrate is heparan sulfate. Heparan sulfate is made by dedicated proteins that help assemble the molecule (biosynthesis). We aim to inhibit three genes that are involved in heparan sulfate production (Exostosin1 (EXT 1), Exostosin 2 (EXT2), and N-Deacetylase And N-Sulfotransferase 2 (NDST2)). Our initial tests show that we can turn down the production of these genes and that doing so reduces the amount of heparan sulfate in the brain. Here, we propose to determine the most effective combination of RNA to reduce heparan sulfate in the brains of mice with Sanfilippo B syndrome. We then plan to study the effects of substrate reduction therapy using this RNA approach on behavior, pathology, and heparan sulfate levels long term. If successful, this approach could be applied to all Sanfilippo types and to other mucopolysaccharidoses (MPS) in which heparan sulfate accumulates in excess.

Does Treatment with Diazoxide or a novel form of Diazoxide Choline elevate the plasma glucose levels in GLUT1 Deficiency Syndrome thus potentially increasing glucose transport the blood brain barrier?

Awardee: Paul Thornton

Institution: Cook Children's Medical Center

Grant Amount: $60,367

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

We propose to study currently available Diazoxide and a novel drug, Diazoxide Choline which is a more palatable tablet formulation, to see if we can elevate the plasma glucose safely and effectively in children and adults with Glut 1 Deficiency Syndrome. We aim to 1) determine if Diazoxide and Diazoxide Choline increase plasma glucose levels measured by continuous glucose monitoring; 2) compare effects of equivalent doses of Diazoxide and Diazoxide Choline on CGM measured glucose; and 3) evaluate safety and tolerability of both forms of Diazoxide.

Selective HDAC6 inhibitors as a novel treatment for CNS pathology in MPS-I

Awardee: Nicolina Cristina Sorrentino

Institution: University of Naples " Federico II"

Grant Amount: $60,378.00

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

The Mucopolysaccharidoses (MPS) are a group of inherited disorders caused by mutations in genes affecting systemic organs with severe involvement of brain and retina tissues. Since the symptoms occur during the first years of life, an early therapeutic intervention to treat the systemic problems is essential. Recently, scientists discovered that MPS is linked to other serious brain diseases like Alzheimer's and Parkinson's. MPS type I represents the most severe MPS caused by the deficiency of Iduronidase (IDUA) protein, responsible for breaking down substances, like glycosaminoglycans (GAG), leading to systemic and cerebral symptoms. The treatment of brain pathology represents the primary goal in developing any therapeutic approach for MPS-I. Along with glycosaminoglycan accumulation that represent the primary storage, another important player of MPS disorder is represented by the block of the cellular 'garbage disposal' process, called autophagy, which cause the accumulation of secondary toxic materials and strongly influence the neuropathology progression. Current therapeutic strategies are based on the restoration of only the functional IDUA protein, which is not sufficient for removing all the secondary storage present in the cells of MPS-I patients. In this light, a new treatment stimulating autophagy and tackling accumulation of toxic materials might restore CNS and retinal health in MPS-I. For this reason, we propose a new pharmacological approach aimed at reactivating the autophagy mechanism, removing storage toxic material, promoting neuroprotection in brain and retina of MPS-I. Advanced pharmacology and cellular biology techniques will be employed to develop selective compounds in order to target and treat MPS-I brain cells. Additionally, biochemical, molecular and immunofluorescence analyses will be performed on MPS-I cell lines in order to validate the effectiveness of the therapy in restoring neuronal function and reducing the accumulation of toxic materials.

Targeting GNAS-Driven Pathway for Precision Therapy of Fibrous Dysplasia

Awardee: J. Silvio Gutkind

Institution: University of California, San Diego

Grant Amount: $80,468.00

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

Fibrous dysplasia (FD) is a rare bone disorder where normal bone is replaced with fibrous tissue, leading to deformities, fractures, and chronic pain. FD is caused by mutations in the GNAS gene, which results in the continuous activation of a signaling pathway that disrupts normal bone formation. This mutation typically occurs early in development and affects not only the skeleton but also other tissues, such as the skin and endocrine organs. Currently, there are no targeted treatments available for FD, and existing therapies are primarily focused on managing symptoms rather than addressing the underlying cause of the disease. Our research aims to better understand how FD develops by studying the stem cells that give rise to the disease and how the GNAS mutation alters their normal function. We will use advanced techniques to investigate these cells at a single-cell level, allowing us to identify the specific molecular changes that drive the progression of FD. In addition, we are exploring new therapeutic strategies by targeting key components of the GNAS signaling pathway. Specifically, we are focusing on inhibiting the PKA catalytic subunit, which is a crucial downstream player in the pathway affected by the GNAS mutation. We believe that blocking this molecule will help restore the balance of bone formation and potentially reverse the progression of FD. By combining our understanding of FD development with new therapeutic approaches, we aim to open the door to more effective treatments for patients with this debilitating condition. Our ultimate goal is to develop targeted therapies that can halt or reverse the progression of FD, improving the life expectancy and quality of life for those affected by the disease.

Elucidating a link between microfractures and fibrous dysplasia bone pain in mice

Awardee: Ariane Zamarioli

Institution: Ribeirao Preto Medical School

Grant Amount: $40,234.00

Funding Period: February 1, 2025 - January 31, 2026

---

Summary:

FD/MAS are severe congenital disorders that result in significant bone pain, skeletal deformities, and endocrine dysfunction. Bone pain is one of the most difficult symptoms to manage in FD/MAS patients. Currently, a variety of pharmacotherapies, including bisphosphonates, are used to alleviate skeletal disease activity and bone pain. However, the mechanisms behind bone pain in FD/MAS remain unclear. Microfractures are suspected to be a contributing factor. This proposal seeks to explore the relationship between FD-related bone pain and microfractures using an established FD animal model.