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Sandra L Hofmann - One of the best experts on this subject based on the ideXlab platform.
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Cross-Linked Enzyme Aggregates as Versatile Tool for Enzyme Delivery: Application to Polymeric Nanoparticles
2018Co-Authors: Marianna Galliani, Sandra L Hofmann, Melissa Santi, Ambra Del Grosso, Antonella Cecchettini, Filippo Maria Santorelli, Lucia Angella, Marco Cecchini, Giovanni SignoreAbstract:Polymeric nanoparticles (NPs) represent one of the most promising tools in nanomedicine and have been extensively studied for the delivery of water-insoluble drugs. However, the efficient loading of therapeutic enzymes and Proteins in polymer-based nanostructures remains an open challenge. Here, we report a synthesis method for a new enzyme delivery system based on cross-linked enzyme aggregates (CLEAs) encapsulation into poly(lactide-co-glycolide) (PLGA) NPs. We tested the encapsulation strategy on four enzymes currently investigated for enzyme replacement therapy: Palmitoyl Protein Thioesterase 1 (PPT1; defective in NCL1 disease), galactosylceramidase (GALC; defective in globoid cell leukodystrophy), alpha glucosidase (aGLU; defective in Pompe disease), and beta glucosidase (bGLU; defective in Gaucher’s disease). We demonstrated that our system allows encapsulation of enzymes with excellent activity retention (usually around 60%), thus leading to functional and targeted nanostructures suitable for enzyme delivery. We then demonstrated that CLEA NPs efficiently deliver PPT1 in cultured cells, with almost complete enzyme release occurring in 48 h. Finally, we demonstrated that enzymatic activity is fully recovered in primary NCL1 fibroblasts upon treatment with PPT1 CLEA NPs
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intravenous high dose enzyme replacement therapy with recombinant Palmitoyl Protein Thioesterase reduces visceral lysosomal storage and modestly prolongs survival in a preclinical mouse model of infantile neuronal ceroid lipofuscinosis
Molecular Genetics and Metabolism, 2012Co-Authors: Andrew Wong, Jonathan D. Cooper, Linda S Hynan, Shari G Birnbaum, Denis S Yilmaz, Barbara M Streit, Ewelina M Lenartowicz, Thomas C M Thompson, Sandra L HofmannAbstract:PPT1-related neuronal ceroid lipofuscinosis (NCL) is a lysosomal storage disorder caused by deficiency in a soluble lysosomal enzyme, Palmitoyl-Protein Thioesterase-1 (PPT1). Enzyme replacement therapy (ERT) has not been previously examined in a preclinical animal model. Homozygous PPT1 knockout mice reproduce the known features of the disease, developing signs of motor dysfunction at 5 months of age and death by around 8 months. In the current study, PPT1 knockout mice were treated with purified recombinant PPT1 (0.3 mg, corresponding to 12 mg/kg or 180 U/kg for a 25 g mouse) administered intravenously weekly either 1) from birth; or 2) beginning at 8 weeks of age. The treatment was surprisingly well tolerated and neither anaphylaxis nor antibody formation was observed. In mice treated from birth, survival increased from 236 to 271 days (p<0.001) and the onset of motor deterioration was similarly delayed. In mice treated beginning at 8 weeks, no increases in survival or motor performance were seen. An improvement in neuropathology in the thalamus was seen at 3 months in mice treated from birth, and although this improvement persisted it was attenuated by 7 months. Outside the central nervous system, substantial clearance of autofluorescent storage material in many tissues was observed. Macrophages in spleen, liver and intestine were especially markedly improved, as were acinar cells of the pancreas and tubular cells of the kidney. These findings suggest that ERT may be an option for addressing visceral storage as part of a comprehensive approach to PPT1-related NCL, but more effective delivery methods to target the brain are needed.
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a mutation in canine ppt1 causes early onset neuronal ceroid lipofuscinosis in a dachshund
Molecular Genetics and Metabolism, 2010Co-Authors: Douglas N Sanders, Sandra L Hofmann, Vivian Chiang, Jui Yun Lu, Fabiana H G Farias, Gary S Johnson, James R Cook, Dennis P Obrien, Martin L KatzAbstract:The neuronal ceroid lipofuscinoses (NCLs) are lysosomal storage diseases characterized by progressive neurodegeneration and accumulation of autofluorescent storage granules. A 9-month-old Miniature Dachshund presented with NCL-like signs that included disorientation, ataxia, weakness, visual impairment, and behavioral changes. Neurons throughout the CNS contained autofluorescent lysosomal inclusions with granular osmiophilic deposit (GROD) ultrastructure characteristic of classical infantile NCL (INCL). Human INCL is an autosomal recessive disorder that results from mutations in PPT1, a gene that encodes the enzyme Palmitoyl Protein Thioesterase 1 (PPT1; EC 3.1.22). Resequencing of PPT1 from the affected dog revealed that the dog was homozygous for a single nucleotide insertion in exon 8 (PPT1 c.736_737insC), upstream from the His289 active site. Brain tissue from this dog lacked PPT1 activity. The sire and dam of the propositus were heterozygous for the c.736_737insC mutation; whereas, 127 unrelated Dachshunds were homozygous for the wild-type allele. This is the first reported instance of canine NCL caused by a mutation in PPT1.
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human recombinant Palmitoyl Protein Thioesterase 1 ppt1 for preclinical evaluation of enzyme replacement therapy for infantile neuronal ceroid lipofuscinosis
Molecular Genetics and Metabolism, 2010Co-Authors: Sandra L HofmannAbstract:Infantile neuronal ceroid lipofuscinosis (INCL, also known as Haltia-Santavuori disease) is a lysosomal storage disorder of infants and children characterized by blindness, seizures and a progressive neurodegenerative course. Recent clinical trials have involved neural stem cells and gene therapy directed to the central nervous system; however, enzyme replacement therapy has never been addressed. In the current paper, we describe the production of human recombinant PPT1 (the defective enzyme in INCL) by standard methods in Chinese Hamster Ovary (CHO) cells. The enzyme is largely mannose 6-phosphorylated as assessed by mannose 6-phosphate receptor binding (80% bound) and taken up rapidly by immortalized patient lymphoblasts, where clearance of PPT substrates was demonstrated (EC(50) of 0.25 nM after overnight incubation). When injected intravenously into PPT1-deficient mice, the clearance of recombinant human PPT1 from plasma was rapid, with a half-life of 10 min. Most of the injected dose was distributed to the kidney and liver and potentially corrective levels were also observed in heart, lung and spleen. Brain uptake was minimal, as expected based on experience with other intravenously administered lysosomal enzymes. The enzyme may be useful as an adjunct to central nervous system-directed therapies and could be used as a starting point for modifications designed to improve brain delivery.
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regional and cellular neuropathology in the Palmitoyl Protein Thioesterase 1 null mutant mouse model of infantile neuronal ceroid lipofuscinosis
Neurobiology of Disease, 2004Co-Authors: Ellen Bible, Praveena Gupta, Sandra L Hofmann, Jonathan D. CooperAbstract:Abstract Infantile neuronal ceroid lipofuscinosis (INCL) is one of a group of fatal hereditary lysosomal storage disorders. Palmitoyl Protein Thioesterase 1 null mutant mice (PPT1−/−) now exist that accurately recapitulate many important disease features. The severely affected PPT1−/− mouse CNS exhibited reduced volume of both cortical and subcortical regions, but with sparing of the cerebellum. Pronounced differences existed in the extent of cortical thinning between different regions, due to lamina-specific effects upon neuronal survival. A dramatic reduction in cortical and hippocampal interneuron number was also evident, with different extents of specific interneuron loss depending upon the region and phenotypic marker. These neuronal changes were accompanied by widespread astrocytosis and localized microglial activation in restricted cortical and subcortical regions. This characterization of PPT1−/− mice not only provides defined pathological landmarks for understanding disease pathogenesis, but also provides an invaluable resource for subsequently judging the efficacy of therapeutic strategies.
Mark S. Sands - One of the best experts on this subject based on the ideXlab platform.
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widespread expression of a membrane tethered version of the soluble lysosomal enzyme Palmitoyl Protein Thioesterase 1
JIMD reports, 2017Co-Authors: Charles Shyng, Shannon L Macauley, Joshua T Dearborn, Mark S. SandsAbstract:“Cross-correction,” the transfer of soluble lysosomal enzymes between neighboring cells, forms the foundation for therapeutics of lysosomal storage disorders (LSDs). However, “cross-correction” poses a significant barrier to studying the role of specific cell types in LSD pathogenesis. By expressing the native enzyme in only one cell type, neighboring cell types are invariably corrected. In this study, we present a strategy to limit “cross-correction” of Palmitoyl-Protein Thioesterase-1(PPT1), a lysosomal hydrolase deficient in Infantile Neuronal Ceroid Lipofuscinosis (INCL, Infantile Batten disease) to the lysosomal membrane via the C-terminus of lysosomal associated membrane Protein-1 (LAMP1). Tethering PPT1 to the lysosomal membrane prevented “cross-correction” while allowing PPT1 to retain its enzymatic function and localization in vitro. A transgenic line harboring the lysosomal membrane-tethered PPT1 was then generated. We show that expression of lysosome-restricted PPT1 in vivo largely rescues the INCL biochemical, histological, and functional phenotype. These data suggest that lysosomal tethering of PPT1 via the C-terminus of LAMP1 is a viable strategy and that this general approach can be used to study the role of specific cell types in INCL pathogenesis, as well as other LSDs. Ultimately, understanding the role of specific cell types in the disease progression of LSDs will help guide the development of more targeted therapeutics.
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astrocytosis in infantile neuronal ceroid lipofuscinosis friend or foe
Biochemical Society Transactions, 2014Co-Authors: Charles Shyng, Mark S. SandsAbstract:Infantile neuronal ceroid lipofuscinosis (INCL; infantile Batten disease) is an inherited paediatric neurodegenerative disease. INCL is caused by a deficiency in the lysosomal enzyme Palmitoyl-Protein Thioesterase-1 (PPT1) and is thus classified as a lysosomal storage disease. Pathological examination of both human and murine INCL brains reveals progressive, widespread neuroinflammation. In fact, astrocyte activation appears to be the first histological sign of disease. However, the role of astrocytosis in INCL was poorly understood. The hallmark of astrocyte activation is the up-regulation of intermediate filaments, such as glial fibrillary acidic Protein (GFAP) and vimentin. The role of astrocytosis in INCL was studied in a murine model lacking PPT1 and the intermediate filaments GFAP and vimentin (triple-knockout). This murine model of INCL with attenuated astrocytosis had an exacerbated pathological and clinical phenotype. The triple-knockout mouse had a significantly shortened lifespan, and accelerated cellular and humoural neuroinflammatory response compared with the parental PPT1−/− mouse. The data obtained from the triple-knockout mouse strongly suggest that astrocyte activation plays a beneficial role in early INCL disease progression. A more thorough understanding of the glial responses to lysosomal enzyme deficiencies and the accumulation of undergraded substrates will be crucial to developing effective therapeutics. Abbreviations: CNS, central nervous system; GFAP, glial fibrillary acidic Protein; INCL, infantile neuronal ceroid lipofuscinosis; LSD, lysosomal storage disorder; NCL, neuronal ceroid lipofuscinosis; PPT1, Palmitoyl-Protein Thioesterase-1
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the role of attenuated astrocyte activation in infantile neuronal ceroid lipofuscinosis
The Journal of Neuroscience, 2011Co-Authors: Shannon L Macauley, Milos Pekny, Mark S. SandsAbstract:Infantile neuronal ceroid lipofuscinosis (INCL) is an inherited neurodegenerative disorder affecting the CNS during infancy. INCL is caused by mutations in the CLN1 gene that lead to a deficiency in the lysosomal hydrolase, Palmitoyl Protein Thioesterase 1 (PPT1). A murine model of INCL, the PPT1-deficient ( PPT1 −/−) mouse, is an accurate phenocopy of the human disease. The first pathological change observed in the PPT1 −/− brain is regional areas of glial fibrillary acidic Protein (GFAP) upregulation, which predicts future areas of neurodegeneration. We hypothesized that preventing GFAP and vimentin upregulation in reactive astrocytes will alter the CNS disease. To test this hypothesis, we generated mice simultaneously carrying null mutations in the GFAP , Vimentin , and PPT1 genes ( GFAP −/− Vimentin −/− PPT1 −/−). Although the clinical and pathological features of the GFAP −/− Vimentin −/− PPT1 −/− mice are similar to INCL, the disease appears earlier and progresses more rapidly. One mechanism underlying this accelerated phenotype is a profound neuroinflammatory response within the CNS. Thus, our data identify a protective role for intermediate filament upregulation during astrocyte activation in INCL, a model of chronic neurodegeneration.
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successive neuron loss in the thalamus and cortex in a mouse model of infantile neuronal ceroid lipofuscinosis
Neurobiology of Disease, 2007Co-Authors: Catherine Kielar, Mark S. Sands, Lucy Maddox, Ellen Bible, Charlie C Pontikis, Shannon L Macauley, Megan A Griffey, Michael Wong, Jonathan D. CooperAbstract:Abstract Infantile neuronal ceroid lipofuscinosis (INCL) is caused by deficiency of the lysosomal enzyme, Palmitoyl Protein Thioesterase 1 (PPT1). We have investigated the onset and progression of pathological changes in Ppt1 deficient mice (Ppt1−/−) and the development of their seizure phenotype. Surprisingly, cortical atrophy and neuron loss occurred only late in disease progression but were preceded by localized astrocytosis within individual thalamic nuclei and the progressive loss of thalamic neurons that relay different sensory modalities to the cortex. This thalamic neuron loss occurred first within the visual system and only subsequently in auditory and somatosensory relay nuclei or the inhibitory reticular thalamic nucleus. The loss of granule neurons and GABAergic interneurons followed in each corresponding cortical region, before the onset of seizure activity. These findings provide novel evidence for successive neuron loss within the thalamus and cortex in Ppt1−/− mice, revealing the thalamus as an important early focus of INCL pathogenesis.
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cns directed aav2 mediated gene therapy ameliorates functional deficits in a murine model of infantile neuronal ceroid lipofuscinosis
Molecular Therapy, 2006Co-Authors: Megan A Griffey, Ellen Bible, Jonathan D. Cooper, Michael Wong, David F Wozniak, Kendra Johnson, Steven M Rothman, Annie E Wentz, Mark S. SandsAbstract:The neuronal ceroid lipofuscinoses (Batten disease) are a group of inherited neurodegenerative diseases characterized by the progressive intralysosomal accumulation of autofluorescent material in many cells, visual defects, seizures, cognitive deficits, and premature death. Infantile neuronal ceroid lipofuscinosis (INCL) has the earliest onset (≈1.5 years of age) and is caused by a deficiency in the lysosomal enzyme Palmitoyl Protein Thioesterase-1 (PPT1). Currently there is no effective treatment for children with INCL. In this study, newborn PPT1-deficient mice received two (cortex), four (cortex and hippocampus), or six (cortex, hippocampus, and cerebellum) bilateral intracranial injections of AAV2-PPT1. The AAV-treated animals had localized increases in PPT1 activity, decreased autofluorescent material, improved histologic parameters, and increased brain mass. In addition, the treated animals had dose-dependent improvements in a battery of behavioral tests and improved interictal electroencephalographic tracings. However, there was neither a significant decrease in seizure frequency nor an increase in longevity even in INCL animals receiving six injections. These data suggest that early treatment of INCL using gene transfer techniques can be efficacious. However, higher levels or a broader distribution of PPT1 expression, or both, will be required for more complete correction of this neurodegenerative disease.
Jonathan D. Cooper - One of the best experts on this subject based on the ideXlab platform.
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an anti neuroinflammatory that targets dysregulated glia enhances the efficacy of cns directed gene therapy in murine infantile neuronal ceroid lipofuscinosis
The Journal of Neuroscience, 2014Co-Authors: Shannon L Macauley, Charles Shyng, Jonathan D. Cooper, Joshua T Dearborn, Andrew Wong, David P Augner, Yewande Pearse, Marie S Roberts, Stephen C Fowler, Martin D WattersonAbstract:Infantile neuronal ceroid lipofuscinosis (INCL) is an inherited neurodegenerative lysosomal storage disease (LSD) caused by a deficiency in Palmitoyl Protein Thioesterase-1 (PPT1). Studies in Ppt1(-/-) mice demonstrate that glial activation is central to the pathogenesis of INCL. Astrocyte activation precedes neuronal loss, while cytokine upregulation associated with microglial reactivity occurs before and concurrent with neurodegeneration. Therefore, we hypothesized that cytokine cascades associated with neuroinflammation are important therapeutic targets for the treatment of INCL. MW01-2-151SRM (MW151) is a blood-brain barrier penetrant, small-molecule anti-neuroinflammatory that attenuates glial cytokine upregulation in models of neuroinflammation such as traumatic brain injury, Alzheimer's disease, and kainic acid toxicity. Thus, we used MW151, alone and in combination with CNS-directed, AAV-mediated gene therapy, as a possible treatment for INCL. MW151 alone decreased seizure susceptibility. When combined with AAV-mediated gene therapy, treated INCL mice had increased life spans, improved motor performance, and eradication of seizures. Combination-treated INCL mice also had decreased brain atrophy, astrocytosis, and microglial activation, as well as intermediary effects on cytokine upregulation. These data suggest that MW151 can attenuate seizure susceptibility but is most effective when used in conjunction with a therapy that targets the primary genetic defect.
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immune cells perturb axons and impair neuronal survival in a mouse model of infantile neuronal ceroid lipofuscinosis
Brain, 2013Co-Authors: Janos Groh, Jonathan D. Cooper, Thomas G Kuhl, Hemanth R Nelvagal, Sarmi Sri, Steven Duckett, Myriam Mirza, Thomas Langmann, Rudolf MartiniAbstract:The neuronal ceroid lipofuscinoses are fatal neurodegenerative disorders in which the visual system is affected early in disease progression. A typical accompanying feature is neuroinflammation, the pathogenic impact of which is presently obscure. Here we investigated the role of inflammatory cells in Palmitoyl Protein Thioesterase 1-deficient ( Ppt1 -/-) mice, a model of infantile neuronal ceroid lipofuscinosis (CLN1 disease, infantile), predominantly focusing on the visual system. We detected an early infiltration of CD8+ T-lymphocytes and observed activation of microglia/macrophage-like cells. To analyse the pathogenic impact of lymphocytes, we crossbred Ppt1 -/- mice with mutants lacking lymphocytes ( Rag1 -/-), and scored axonal transport, axonal perturbation and neuronal survival. This lack of lymphocytes led to a significant amelioration of disease phenotypes, not only in the retino-tectal system, but also in other regions of the central nervous system. Finally, reconstitution experiments revealed a crucial role of CD8+ T-lymphocytes in pathogenesis. Our study provides novel pathomechanistic insights that may be crucial for developing treatment strategies. * Abbreviation : MHC : major histocompatibility complex
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intravenous high dose enzyme replacement therapy with recombinant Palmitoyl Protein Thioesterase reduces visceral lysosomal storage and modestly prolongs survival in a preclinical mouse model of infantile neuronal ceroid lipofuscinosis
Molecular Genetics and Metabolism, 2012Co-Authors: Andrew Wong, Jonathan D. Cooper, Linda S Hynan, Shari G Birnbaum, Denis S Yilmaz, Barbara M Streit, Ewelina M Lenartowicz, Thomas C M Thompson, Sandra L HofmannAbstract:PPT1-related neuronal ceroid lipofuscinosis (NCL) is a lysosomal storage disorder caused by deficiency in a soluble lysosomal enzyme, Palmitoyl-Protein Thioesterase-1 (PPT1). Enzyme replacement therapy (ERT) has not been previously examined in a preclinical animal model. Homozygous PPT1 knockout mice reproduce the known features of the disease, developing signs of motor dysfunction at 5 months of age and death by around 8 months. In the current study, PPT1 knockout mice were treated with purified recombinant PPT1 (0.3 mg, corresponding to 12 mg/kg or 180 U/kg for a 25 g mouse) administered intravenously weekly either 1) from birth; or 2) beginning at 8 weeks of age. The treatment was surprisingly well tolerated and neither anaphylaxis nor antibody formation was observed. In mice treated from birth, survival increased from 236 to 271 days (p<0.001) and the onset of motor deterioration was similarly delayed. In mice treated beginning at 8 weeks, no increases in survival or motor performance were seen. An improvement in neuropathology in the thalamus was seen at 3 months in mice treated from birth, and although this improvement persisted it was attenuated by 7 months. Outside the central nervous system, substantial clearance of autofluorescent storage material in many tissues was observed. Macrophages in spleen, liver and intestine were especially markedly improved, as were acinar cells of the pancreas and tubular cells of the kidney. These findings suggest that ERT may be an option for addressing visceral storage as part of a comprehensive approach to PPT1-related NCL, but more effective delivery methods to target the brain are needed.
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neuroprotection of host cells by human central nervous system stem cells in a mouse model of infantile neuronal ceroid lipofuscinosis
Cell Stem Cell, 2009Co-Authors: Stanley Tamaki, Jonathan D. Cooper, Yakop Jacobs, Monika Dohse, Alexandra Capela, Michael J Reitsma, Dongping He, Robert Tushinski, Pavel V Belichenko, Ahmad SalehiAbstract:SUMMARY Infantile neuronal ceroid lipofuscinosis (INCL) is a fatal neurodegenerative disease caused by a deficiency in the lysosomal enzyme Palmitoyl Protein Thioesterase-1 (PPT1). Ppt1 knockout mice display hallmarks of INCL and mimic the human pathology: accumulation of lipofuscin, degeneration of CNS neurons, and a shortened life span. Purified nongenetically modified human CNS stem cells, grown as neurospheres (hCNS-SCns), were transplanted into the brains of immunodeficient Ppt1 / mice where they engrafted robustly, migrated extensively, and produced sufficient levels of PPT1 to alter host neuropathology. Grafted mice displayed reduced autofluorescent lipofuscin, significant neuroprotection of host hippocampal and cortical neurons, and delayed loss of motor coordination. Early intervention with cellular transplants of hCNS-SCns into the brains of INCL patients may supply a continuous and long-lasting source of the missing PPT1 and provide some therapeutic benefit through protection of endogenous neurons. These data provide the experimental basis for human clinical trials with these banked hCNS-SCns.
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successive neuron loss in the thalamus and cortex in a mouse model of infantile neuronal ceroid lipofuscinosis
Neurobiology of Disease, 2007Co-Authors: Catherine Kielar, Mark S. Sands, Lucy Maddox, Ellen Bible, Charlie C Pontikis, Shannon L Macauley, Megan A Griffey, Michael Wong, Jonathan D. CooperAbstract:Abstract Infantile neuronal ceroid lipofuscinosis (INCL) is caused by deficiency of the lysosomal enzyme, Palmitoyl Protein Thioesterase 1 (PPT1). We have investigated the onset and progression of pathological changes in Ppt1 deficient mice (Ppt1−/−) and the development of their seizure phenotype. Surprisingly, cortical atrophy and neuron loss occurred only late in disease progression but were preceded by localized astrocytosis within individual thalamic nuclei and the progressive loss of thalamic neurons that relay different sensory modalities to the cortex. This thalamic neuron loss occurred first within the visual system and only subsequently in auditory and somatosensory relay nuclei or the inhibitory reticular thalamic nucleus. The loss of granule neurons and GABAergic interneurons followed in each corresponding cortical region, before the onset of seizure activity. These findings provide novel evidence for successive neuron loss within the thalamus and cortex in Ppt1−/− mice, revealing the thalamus as an important early focus of INCL pathogenesis.
Anu Jalanko - One of the best experts on this subject based on the ideXlab platform.
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Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons-1
2011Co-Authors: Annina Lyly, Carina Von Schantz, Tarja Salonen, Outi Kopra, Jani Saarela, Matti Jauhiainen, Aija Kyttala, Anu JalankoAbstract:Copyright information:Taken from "Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons"http://www.biomedcentral.com/1471-2121/8/22BMC Cell Biology 2007;8():22-22.Published online 12 Jun 2007PMCID:PMC1906764. + S214A. The cells were double-stained using the polyclonal antibody for PPT1 (red) and the monoclonal antibody for LAMP-1, lysosomal membrane Protein (green). Colocalization is shown in yellow
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Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons-10
2011Co-Authors: Annina Lyly, Carina Von Schantz, Tarja Salonen, Outi Kopra, Jani Saarela, Matti Jauhiainen, Aija Kyttala, Anu JalankoAbstract:Copyright information:Taken from "Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons"http://www.biomedcentral.com/1471-2121/8/22BMC Cell Biology 2007;8():22-22.Published online 12 Jun 2007PMCID:PMC1906764.+ S214A. The cells were double-stained using the polyclonal antibody for PPT1 (red) and the monoclonal antibody for LAMP-1, lysosomal membrane Protein (green). Colocalization is shown in yellow
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Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons-3
2011Co-Authors: Annina Lyly, Carina Von Schantz, Tarja Salonen, Outi Kopra, Jani Saarela, Matti Jauhiainen, Aija Kyttala, Anu JalankoAbstract:Copyright information:Taken from "Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons"http://www.biomedcentral.com/1471-2121/8/22BMC Cell Biology 2007;8():22-22.Published online 12 Jun 2007PMCID:PMC1906764.ion was subjected to size exclusion chromatography and the PPT1 and AGA enzyme activities were measured from the fractions collected. The X-axis indicates time and the molecular weights are derived from the standard (Bio-Rad)
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Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons-6
2011Co-Authors: Annina Lyly, Carina Von Schantz, Tarja Salonen, Outi Kopra, Jani Saarela, Matti Jauhiainen, Aija Kyttala, Anu JalankoAbstract:Copyright information:Taken from "Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons"http://www.biomedcentral.com/1471-2121/8/22BMC Cell Biology 2007;8():22-22.Published online 12 Jun 2007PMCID:PMC1906764.ned for PPT1 using the GST-PPT1 antibody (green), for lysosomes using the Lamp-1 antibody (red), for synaptic vesicles using the SV2 antibody (red) and for ER using the PDI antibody (red). Colocalization is shown in yellow. Scale bar = 20 μm
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Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons-4
2011Co-Authors: Annina Lyly, Carina Von Schantz, Tarja Salonen, Outi Kopra, Jani Saarela, Matti Jauhiainen, Aija Kyttala, Anu JalankoAbstract:Copyright information:Taken from "Glycosylation, transport, and complex formation of Palmitoyl Protein Thioesterase 1 (PPT1) – distinct characteristics in neurons"http://www.biomedcentral.com/1471-2121/8/22BMC Cell Biology 2007;8():22-22.Published online 12 Jun 2007PMCID:PMC1906764.1, GFP-CLN3 or GFP-AIRE). The lysates were immunoprecipitated with anti-GFP-conjugated agarose beads. Both lysates (Transfection control) and immunoprecipitated samples (Anti-GFP-IP) were analyzed by immunoblotting using the anti-PPT1 antibody. * = Unspecific binding. Biacore assay investigating the self-interaction of purified PPT1 (see methods)
Arjun Saha - One of the best experts on this subject based on the ideXlab platform.
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cln1 mutations suppress rab7 rilp interaction and impair autophagy contributing to neuropathology in a mouse model of infantile neuronal ceroid lipofuscinosis
Journal of Inherited Metabolic Disease, 2020Co-Authors: Arjun Saha, Goutam Chandra, Chinmoy Sarkar, Abhilash P Appu, Maria B Bagh, Tamal Sadhukhan, Avisek MondalAbstract:Infantile neuronal ceroid lipofuscinosis (INCL) is a devastating neurodegenerative lysosomal storage disease (LSD) caused by inactivating mutations in the CLN1 gene. CLN1 encodes Palmitoyl-Protein Thioesterase-1 (PPT1), a lysosomal enzyme that catalyzes the deacylation of S-Palmitoylated Proteins to facilitate their degradation and clearance by lysosomal hydrolases. Despite the discovery more than two decades ago that CLN1 mutations causing PPT1-deficiency underlies INCL, the precise molecular mechanism(s) of pathogenesis has remained elusive. Here, we report that autophagy is dysregulated in Cln1 -/- mice, which mimic INCL and in postmortem brain tissues as well as cultured fibroblasts from INCL patients. Moreover, Rab7, a small GTPase, critical for autophagosome-lysosome fusion, requires S-Palmitoylation for trafficking to the late endosomal/lysosomal membrane where it interacts with Rab-interacting lysosomal Protein (RILP), essential for autophagosome-lysosome fusion. Notably, PPT1-deficiency in Cln1 -/- mice, dysregulated Rab7-RILP interaction and preventing autophagosome-lysosome fusion, which impaired degradative functions of the autolysosome leading to INCL pathogenesis. Importantly, treatment of Cln1 -/- mice with a brain-penetrant, PPT1-mimetic, small molecule, N-tert (butyl)hydroxylamine (NtBuHA), ameliorated this defect. Our findings reveal a previously unrecognized role of CLN1/PPT1 in autophagy and suggest that small molecules functionally mimicking PPT1 may have therapeutic implications.
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In a Model of Batten Disease, Palmitoyl Protein Thioesterase-1 Deficiency Is Associated with Brown Adipose Tissue and Thermoregulation Abnormalities
2016Co-Authors: Alfia Khaibullina, Zhongjian Zhang, Nicholas Kenyon, Virginia Guptill, Martha M. Quezado, Li Wang, Deloris Koziol, Robert Wesley, Pablo R. Moya, Arjun SahaAbstract:Infantile neuronal ceroid lipofuscinosis (INCL) is a fatal neurodegenerative disorder caused by a deficiency of Palmitoyl-Protein Thioesterase-1 (PPT1). We have previously shown that children with INCL have increased risk of hypothermia during anesthesia and that PPT1-deficiency in mice is associated with disruption of adaptive energy metabolism, downregulation of peroxisome proliferator-activated receptor c coactivator 1a (PGC-1a), and mitochondrial dysfunction. Here we hypothesized that Ppt1-knockout mice, a well-studied model of INCL that shows many of the neurologic manifestations of the disease, would recapitulate the thermoregulation impairment observed in children with INCL. We also hypothesized that when exposed to cold, Ppt1-knockout mice would be unable to maintain body temperature as in mice thermogenesis requires upregulation of Pgc-1a and uncoupling Protein 1 (Ucp-1) in brown adipose tissue. We found that the Ppt1-KO mice had lower basal body temperature as they aged and developed hypothermia during cold exposure. Surprisingly, thi
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in a model of batten disease Palmitoyl Protein Thioesterase 1 deficiency is associated with brown adipose tissue and thermoregulation abnormalities
PLOS ONE, 2012Co-Authors: Alfia Khaibullina, Zhongjian Zhang, Virginia Guptill, Martha M. Quezado, Li Wang, Robert Wesley, Pablo R. Moya, Nicholas J Kenyon, Deloris E Koziol, Arjun SahaAbstract:Infantile neuronal ceroid lipofuscinosis (INCL) is a fatal neurodegenerative disorder caused by a deficiency of Palmitoyl-Protein Thioesterase-1 (PPT1). We have previously shown that children with INCL have increased risk of hypothermia during anesthesia and that PPT1-deficiency in mice is associated with disruption of adaptive energy metabolism, downregulation of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), and mitochondrial dysfunction. Here we hypothesized that Ppt1-knockout mice, a well-studied model of INCL that shows many of the neurologic manifestations of the disease, would recapitulate the thermoregulation impairment observed in children with INCL. We also hypothesized that when exposed to cold, Ppt1-knockout mice would be unable to maintain body temperature as in mice thermogenesis requires upregulation of Pgc-1α and uncoupling Protein 1 (Ucp-1) in brown adipose tissue. We found that the Ppt1-KO mice had lower basal body temperature as they aged and developed hypothermia during cold exposure. Surprisingly, this inability to maintain body temperature during cold exposure in Ppt1-KO mice was associated with an adequate upregulation of Pgc-1α and Ucp-1 but with lower levels of sympathetic neurotransmitters in brown adipose tissue. In addition, during baseline conditions, brown adipose tissue of Ppt1-KO mice had less vacuolization (lipid droplets) compared to wild-type animals. After cold stress, wild-type animals had significant decreases whereas Ppt1-KO had insignificant changes in lipid droplets compared with baseline measurements, thus suggesting that Ppt1-KO had less lipolysis in response to cold stress. These results uncover a previously unknown phenotype associated with PPT1 deficiency, that of altered thermoregulation, which is associated with impaired lipolysis and neurotransmitter release to brown adipose tissue during cold exposure. These findings suggest that INCL should be added to the list of neurodegenerative diseases that are linked to alterations in peripheral metabolic processes. In addition, extrapolating these findings clinically, impaired thermoregulation and hypothermia are potential risks in patients with INCL.
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Omega-3 and omega-6 fatty acids suppress ER- and oxidative-stress in cultured neurons and neuronal progenitor cells from mice lacking PPT1
Neuroscience letters, 2010Co-Authors: Sungjo Kim, Zhongjian Zhang, Arjun Saha, Chinmoy Sarkar, Zhenwen Zhao, Anil B MukherjeeAbstract:Reactive oxygen species (ROS) damage brain lipids, carbohydrates, Proteins, as well as DNA and may contribute to neurodegeneration. We previously reported that ER- and oxidative stress cause neuronal apoptosis in infantile neuronal ceroid lipofuscinosis (INCL), a lethal neurodegenerative storage disease, caused by Palmitoyl-Protein Thioesterase-1 (PPT1) deficiency. Polyunsaturated fatty acids (PUFA) are essential components of cell membrane phospholipids in the brain and excessive ROS may cause oxidative damage of PUFA leading to neuronal death. Using cultured neurons and neuroprogenitor cells from mice lacking Ppt1, which mimic INCL, we demonstrate that Ppt1-deficient neurons and neuroprogenitor cells contain high levels of ROS, which may cause peroxidation of PUFA and render them incapable of providing protection against oxidative stress. We tested whether treatment of these cells with omega-3 or omega-6 PUFA protects the neurons and neuroprogenitor cells from oxidative stress and suppress apoptosis. We report here that both omega-3 and omega-6 fatty acids protect the Ppt1-deficient cells from ER- as well as oxidative stress and suppress apoptosis. Our results suggest that PUFA supplementation may have neuroprotective effects in INCL.
