Publications by authors named "Xuntian Jiang"

Though it has no catalytic activity toward GM2 ganglioside, the GM2 activator protein (GM2A) is essential for ganglioside hydrolysis by facilitating the action of lysosomal ß-N-acetylhexosaminidase. GM2A deficiency results in death in early childhood due to rapid central nervous system deterioration similar to the related GM2 gangliosidoses, Tay-Sachs disease and Sandhoff disease. This manuscript further characterizes a feline model of GM2A deficiency with a focus on clinical and biochemical parameters that may be useful as benchmarks for translational therapeutic research.

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Background: Pancreatic ductal adenocarcinoma (PDAC) has a high fatality rate, with surgery as the only curative treatment. Identification of new biomarkers related to survival may help guide discovery of new pathophysiologic pathways and potential therapeutic targets. As long-chain ceramides have been linked to tumor proliferation, we sought to determine if ceramide levels were prognostic in PDAC.

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Lysosomal function is impaired in Niemann-Pick disease type C1 (NPC1), a rare and inherited neurodegenerative disorder, resulting in late endosomal/lysosomal accumulation of unesterified cholesterol. The precise pathogenic mechanism of NPC1 remains incompletely understood. In this study, we employed metabolomics to uncover secondary accumulated substances in NPC1.

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Ceramides and cardiorespiratory (CR) fitness are both related to cardiovascular diseases. The associations of three blood plasma ceramides (C16:0, C22:0, and C24:0) with CR fitness in the population-based Study of Health in Pomerania (SHIP-START-1; n = 1,102; mean age 50.3 years, 51.

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Gaucher disease (GD) is a lysosomal storage disorder stemming from biallelic mutations in , characterized by glucocerebrosidase dysfunction and glucocerebroside and glucosylsphingosine accumulation. Since phenotypes of murine models of GD often differ from those in patients, the careful characterization of mutant mice is necessary to establish their ability to model GD. We performed side-by-side comparative biochemical and pathologic analyses of four murine models with genotypes L444P/L444P (p.

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Background: GM1 gangliosidosis is a rare, fatal, neurodegenerative disease caused by mutations in the GLB1 gene and deficiency in β-galactosidase. Delay of symptom onset and increase in lifespan in a GM1 gangliosidosis cat model after adeno-associated viral (AAV) gene therapy treatment provide the basis for AAV gene therapy trials. The availability of validated biomarkers would greatly improve assessment of therapeutic efficacy.

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Background: Diarrheagenic Escherichia coli (DEC) are common pathogens infecting children during their growth and development. Determining the epidemiology and the impact of DEC on child anthropometric measures informs prioritization of prevention efforts. These relationships were evaluated in a novel setting, Cap-Haitien, Haiti.

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Acid sphingomyelinase deficiency (ASMD) is a lysosomal storage disorder caused by mutations in the SMPD1 gene encoding for the acid sphingomyelinase (ASM). While intravenous infusion of recombinant ASM is an effective treatment for the peripheral disease, the neurological complications of ASMD remain unaddressed. It has been shown that aberrantly high level of total brain sphingomyelin (SM) is a key pathological event leading to neurodegeneration.

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Article Synopsis
  • * Researchers created a mouse model using CRISPR/Cas9 to study the disease, which mimics characteristics seen in human patients, such as specific gait abnormalities and a reduction in motor skills over time.
  • * The Glb1 mice also display progressive brain atrophy and increased levels of a pentasaccharide biomarker, supporting their relevance for developing new treatments for GM1 gangliosidosis, particularly the less severe type II variant.
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Plasmodium cynomolgi causes zoonotic malarial infections in Southeast Asia and this parasite species is important as a model for Plasmodium vivax and Plasmodium ovale. Each of these species produces hypnozoites in the liver, which can cause relapsing infections in the blood. Here we present methods and data generated from iterative longitudinal systems biology infection experiments designed and performed by the Malaria Host-Pathogen Interaction Center (MaHPIC) to delve deeper into the biology, pathogenesis, and immune responses of P.

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Background: Children with recurrent infectious diarrhea are susceptible to growth faltering. DHA and choline may play a role in this relationship due to their involvement in lipid metabolism, gut immunity, and inflammatory pathways.

Objectives: This study aimed to characterize the contributions made by DHA and choline status and enteric damage in young children in the association between diarrheal illness and child growth.

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Krabbe Disease (KD) is a lysosomal storage disorder characterized by the genetic deficiency of the lysosomal enzyme β-galactosyl-ceramidase (GALC). Deficit or a reduction in the activity of the GALC enzyme has been correlated with the progressive accumulation of the sphingolipid metabolite psychosine, which leads to local disruption in lipid raft architecture, diffuse demyelination, astrogliosis, and globoid cell formation. The mouse, the most used animal model, has a nonsense mutation, which limits the study of how different mutations impact the processing and activity of GALC enzyme.

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Niemann-Pick C is a rare neurodegenerative, lysosomal storage disease caused by accumulation of unesterified cholesterol. Diagnosis of the disease is often delayed due to its rarity, the heterogeneous presentation and the early non-specific symptoms. The discovery of disease-specific biomarkers - cholestane-3β,5α,6β-triol (C-triol), trihydroxycholanic acid glycinate (TCG) and -palmitoyl-O-phosphocholineserine (PPCS, initially referred to as lysoSM-509) - has led to development of non-invasive, blood-based diagnostics.

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Tay-Sachs disease (TSD) is an inherited neurological disorder caused by deficiency of hexosaminidase A (HexA). Here, we describe an adeno-associated virus (AAV) gene therapy expanded-access trial in two patients with infantile TSD (IND 18225) with safety as the primary endpoint and no secondary endpoints. Patient TSD-001 was treated at 30 months with an equimolar mix of AAVrh8-HEXA and AAVrh8-HEXB administered intrathecally (i.

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Background: Niemann-Pick disease, type C (NPC) is a childhood-onset, lethal, neurodegenerative disorder caused by autosomal recessive mutations in the genes NPC1 or NPC2 and characterized by impaired cholesterol homeostasis, a lipid essential for cellular function. Cellular cholesterol levels are tightly regulated, and mutations in either NPC1 or NPC2 lead to deficient transport and accumulation of unesterified cholesterol in the late endosome/lysosome compartment, and progressive neurodegeneration in affected individuals. Previous cell-based studies to understand the NPC cellular pathophysiology and screen for therapeutic agents have mainly used patient fibroblasts.

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Dyslipidemia and resulting lipotoxicity are pathologic signatures of metabolic syndrome and type 2 diabetes. Excess lipid causes cell dysfunction and induces cell death through pleiotropic mechanisms that link to oxidative stress. However, pathways that regulate the response to metabolic stress are not well understood.

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Tay-Sachs disease (TSD) is a fatal neurodegenerative disease caused by a deficiency of the enzyme β-N-acetylhexosaminidase A (HexA). TSD naturally occurs in Jacob sheep is the only experimental model of TSD. TSD in sheep recapitulates neurologic features similar to juvenile onset and late onset TSD patients.

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Niemann-Pick C1 disease (NPC1) is a rare, fatal neurodegenerative disease caused by mutations in , which encodes the lysosomal cholesterol transport protein NPC1. Disease pathology involves lysosomal accumulation of cholesterol and lipids, leading to neurological and visceral complications. Targeting the central nervous system (CNS) from systemic circulation complicates treatment of neurological diseases with gene transfer techniques.

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Krabbe disease (KD) and metachromatic leukodystrophy (MLD) are caused by accumulation of the glycolipids galactosylceramide (GalCer) and sulfatide and their toxic metabolites psychosine and lysosulfatide, respectively. We discovered a potent and selective small molecule inhibitor (S202) of ceramide galactosyltransferase (CGT), the key enzyme for GalCer biosynthesis, and characterized its use as substrate reduction therapy (SRT). Treating a KD mouse model with S202 dose-dependently reduced GalCer and psychosine in the central (CNS) and peripheral (PNS) nervous systems and significantly increased lifespan.

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Introduction: Niemann-Pick C (NPC) is an autosomal recessive disease due to defective NPC1 or NPC2 proteins resulting in -lysosomal storage of unesterified cholesterol in the central nervous system and liver. Acute liver disease in the newborn period may be self-limited or fatal. 2-hydroxypropyl-β-cyclodextrin (2HPBCD) is a cholesterol-binding agent that reduces lysosomal cholesterol storage.

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GM1-gangliosidosis is a lysosomal disease resulting from a deficiency in the hydrolase β-galactosidase (β-gal) and subsequent accumulation of gangliosides, primarily in neuronal tissue, leading to progressive neurological deterioration and eventually early death. Lysosomal diseases with neurological involvement have limited non-invasive therapies due to the inability of lysosomal enzymes to cross the blood-brain barrier (BBB). A novel fusion enzyme, labeled mTfR-GLB1, was designed to act as a ferry across the BBB by fusing β-gal to the mouse monoclonal antibody against the mouse transferrin receptor and tested in a murine model of GM1-gangliosidosis (β-gal).

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Oxysterols are oxidized derivatives of cholesterol that play regulatory roles in lipid biosynthesis and homeostasis. How oxysterol signaling coordinates different lipid classes such as sterols and triglycerides remains incompletely understood. Here, we show that 4β-hydroxycholesterol (HC) (4β-HC), a liver and serum abundant oxysterol of poorly defined functions, is a potent and selective inducer of the master lipogenic transcription factor, SREBP1c, but not the related steroidogenic transcription factor SREBP2.

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Infantile globoid cell leukodystrophy (GLD, Krabbe disease) is a demyelinating disease caused by the deficiency of the lysosomal enzyme galactosylceramidase (GALC) and the progressive accumulation of the toxic metabolite psychosine. We showed previously that central nervous system (CNS)-directed, adeno-associated virus (AAV)2/5-mediated gene therapy synergized with bone marrow transplantation and substrate reduction therapy (SRT) to greatly increase therapeutic efficacy in the murine model of Krabbe disease (Twitcher). However, motor deficits remained largely refractory to treatment.

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