Glitazone Treatment Rescues Phenotypic Deficits in a Fly Model of Gaucher/Parkinson's Disease.

Parkinson's Disease (PD) is the most common movement disorder, and the strongest genetic risk factor for PD is mutations in the glucocerebrosidase gene (GBA). Mutations in GBA also lead to the development of Gaucher Disease (GD), the most common type of lysosomal storage disorder. Current therapeutic approaches fail to address neurological GD symptoms. Therefore, identifying therapeutic strategies that improve the phenotypic traits associated with GD/PD in animal models may provide an opportunity for treating neurological manifestations of GD/PD. Thiazolidinediones (TZDs, also called glitazones) are a class of compounds targeted for the treatment of type 2 diabetes, and have also shown promise for the treatment of neurodegenerative disease, including PD. Here, we tested the efficacy of glitazone administration during development in a fly GD model with deletions in the GBA homolog, dGBA1b (GBA1ΔTT/ΔTT). We observed an optimal dose of pioglitazone (PGZ) at a concentration of 1 µM that reduced sleep deficits, locomotor impairments, climbing defects, and restoration of normal protein levels of Ref(2)P, a marker of autophagic flux, in GBA1ΔTT/ΔTT mutant flies, compared to GBA1+/+ control flies. These data suggest that PGZ may represent a potential compound with which to treat GD/PD by improving function of lysosomal-autophagy pathways, a cellular process that removes misfolded or aggregated proteins.

Predicting the probability of Gaucher disease in subjects with splenomegaly and thrombocytopenia.

Hematologists are frequently involved in the diagnostic pathway of Gaucher disease type 1 (GD1) patients since they present several hematological signs. However, GD1 is mainly underdiagnosed because of a lack of awareness. In this multicenter study, we combine the use of a diagnostic algorithm with a simple test (ß-glucosidase activity on Dried Blood Spot) in order to facilitate the diagnosis in a population presenting to the hematologist with splenomegaly and/or thrombocytopenia associated with other hematological signs. In this high-risk population, the prevalence of GD1 is 3.3%. We propose an equation that predicts the probability of having GD1 according to three parameters that are routinely evaluated: platelet count, ferritin, and transferrin saturation.

Longevity of total hip arthroplasty implants in patients with Gaucher disease.

BACKGROUND: Total hip replacement (THR) is performed for arthritic hip joints, which in Gaucher disease results from osteonecrosis of the femoral head. This procedure was recommended as valid and safe for this group of patients. Nevertheless, long term outcome has not been evaluated in a large cohort. METHODS: Data regarding all patients having hip replacement in a relatively large Gaucher clinic was collected. Specifically, details such as patient background and quality of life, implant types, radiographic signs of implant-loosening, and success of implant revision were gathered. RESULTS: The cohort included 48 patients (females 42%, mean age at operation 42 ± 14 years), having 54 hip implants. 15 years survival was 60% and an average implant life was 12.8 years. Longevity was related to implant type, with cementless implants using ceramic-on-ceramic bearing surfaces performing better than other types (no revisions so-far). Older age at surgery also involved a lower revision risk. Gender, disease genotype, and use of cement during the procedure did not have significant effect on longevity. As expected, quality of life and hip related function were better for patients who did not undergo revision. This implies the importance of long-term implant survival. CONCLUSION: Based on these results we recommend THR as a viable treatment for symptomatic hip arthrosis, especially at older age. Specifically, the utilisation of ceramic on ceramic bearing surfaced shows promising result in patients with Gauchers disease.

ß-Glycosphingolipids as Mediators of Both Inflammation and Immune Tolerance: A Manifestation of Randomness in Biological Systems.

Plasticity in biological systems is attributed to the combination of multiple parameters which determine function. These include genotypic, phenotypic, and environmental factors. While biological processes can be viewed as ordered and sequential, biological randomness was suggested to underline part of them. The present review looks into the concept of randomness in biological systems by exploring the glycosphingolipids-NKT cells example. NKT cells are a unique subset of regulatory lymphocytes which play a role in both inflammation and tolerance. Glycosphingolipids promote an immune balance by changing different arms of the immune system in opposing environments. Traditional immunology looks at skewing the immune system into different directions by different types of activation of the same cell stimulation of different cells subsets, use of different ligands, or different the effect of different immune environments. While these may explain some of the effects, the lack of consistency and opposing results under similar settings may involve randomness which may also be part of real life effects of immunomodulatory agents. It means that several of the biological processes, cannot be explained by simple linear models, and may involve more complex concepts. The application for these concepts for improving therapies to patients with Gaucher disease are discussed. SUMMARY  The use of different ligands that target a variety of cell subsets in different immune environments may underlie differences in the functionality of NKT cells and their variability in response to NKT-based therapies. The novel concept of randomness in biology means that several biological processes cannot be solely explained by simple linear models and may instead involve much more complicated schemes of random disorder. These may have implications on future design of therapeutic regimens for improving the response to current treatments.

Ophthalmic manifestations of Gaucher disease: the most common lysosomal storage disorder.

Gaucher disease (GD) results from a deficiency of glucocerebrosidase activity and the subsequent accumulation of the enzyme's metabolites, principally glucosylsphingosine and glucosylceramide. There are three principal forms: Type I, which is the most common, is usually considered non-neuronopathic. Type II, III and IIIc manifest earlier and have neurological sequelae due to markedly reduced enzyme activity. Gaucher's can be associated with ophthalmological sequelae but these have not been systematically reviewed. We therefore performed a comprehensive literature review of all such ophthalmic abnormalities associated with the different types of Gaucher disease. We systematically searched the literature (1950 - present) for functional and structural ocular abnormalities arising in patients with Gaucher disease and found that all subtypes can be associated with ophthalmic abnormalities; these range from recently described intraocular lesions to disease involving the adnexae, peripheral nerves and brain. In summary, Gaucher can affect most parts of the eye. Rarely is it sight-threatening; some but not all manifestations are amenable to treatment, including with enzyme replacement and substrate reduction therapy. Retinal involvement is rare but patients with ocular manifestations should be monitored and treated early to reduce the risk of progression and further complications. As Gaucher disease is also associated with Parkinsons disease and may also confer an increased risk of malignancy (particularly haematological forms and melanoma), any ocular abnormalities should be fully investigated to exclude these potential underlying conditions.

Enfermedad de Gaucher, diagnostico en el embarazo, reporte de caso y consideraciones de su tratamiento en Colombia / Gaucher disease, diagnosis in pregnancy, report case study and considerations of its treatment in Colombia

RESUMEN Introducción y Objetivo: La enfermedad de Gaucher es una condición autosómica recesiva de baja prevalencia, de difícil diagnóstico y manejo, especialmente en embarazo. Reportamos una gestante con enfermedad de Gaucher manejada desde la semana 15,3 hasta el término del embarazo con Taliglucerasa en la Unidad de Alta Complejidad Obstétrica, en la Fundación Valle del Lili en Cali, Colombia. Métodos: Reporte de caso de gestante con diagnóstico de enfermedad de Gaucher diagnosticada durante el embarazo, con exacerbación de síntomas, quien presento severa pancitopenia y esplenomegalia. Resultados: El manejo medico interdiscilplinario permitió el control del severo deterioro clínico de la paciente durante el parto, presentó hemorragia postparto con choque hipovolémico, con adecuada respuesta al manejo médico. La madre y el neonato fueron dados de alta sin otras complicaciones asociadas. Conclusión: El manejo interdisciplinario es indispensable en gestantes con esta entidad para lograr buenos resultados maternos y perinatales.

ABSTRACT Introduction and Objective: Gaucher disease is a low prevalence autosomal recessive condition, difficult to diagnose and manage especially during pregnancy. We reported a pregnant woman with Gaucher disease managed with Taliglucerase in a critical care obstetric unit from week 15.3 until the end of her pregnancy, at the Fundación Valle del Lili, Cali, Colombia. Methods: A case report of a pregnant woman diagnosed during her pregnancy with Gaucher disease, who presented severe pancytopenia and splenomegaly. Results: The interdisciplinary medical management allowed the control of the severe clinical deterioration of the patient. During the delivery, she presented postpartum hemorrhage with hypovolemic shock, which resolved with medical management. The mother and the newborn were discharged without other associated complications. Conclusion: Interdisciplinary management is essential for handling a critically ill obstetric patient with Gaucher disease, and to achieve good maternal and perinatal outcomes.

A rare form of Gaucher disease resulting from saposin C deficiency.

Gaucher disease is mainly caused by the deficiency of lysosomal acid ß-glucosidase. Gaucher disease caused by the deficiency of saposin C is rare. Here we report a patient mainly presenting with hepatosplenomegaly, thrombocytopenia and anemia. EEG examination revealed increased theta waves. Gaucher cells identified in his bone marrow and the highly elevated plasma chitotriosidase activity and glucosylsphingosine supported a diagnosis of Gaucher disease. However, the leukocyte ß-glucosidase activity was in a normal range. Sanger sequencing revealed a novel maternal exonic mutation c.1133C>G (p.Pro378Arg) in exon 10 of the PSAP gene, which codes the Sap C domain of PSAP protein. To search for other underlying mutations in this patient, whole genome sequencing was applied and revealed a deletion involving exon 2 to 7 of PSAP gene. The deletion appears as a de novo event on paternal chromosome. We concluded that biallelic mutations of PSAP gene were the cause of this patient's Gaucher disease. Our finding expands the mutation spectrum of Gaucher disease with saposin C deficiency.

Hyperferritinemia and iron metabolism in Gaucher disease: Potential pathophysiological implications.

Gaucher disease (GD) is characterized by large amounts of lipid-storing macrophages and is associated with accumulation of iron. High levels of ferritin are a hallmark of the disease. The precise mechanism underlying the changes in iron metabolism has not been elucidated. A systematic search was conducted to summarize available evidence from the literature on iron metabolism in GD and its potential pathophysiological implications. We conclude that in GD, a chronic low grade inflammation state can lead to high ferritin levels and increased hepcidin transcription with subsequent trapping of ferritin in macrophages. Extensive GD manifestations with severe anemia or extreme splenomegaly can lead to a situation of iron-overload resembling hemochromatosis. We hypothesize that specifically this latter situation carries a risk for the occurrence of associated conditions such as the increased cancer risk, metabolic syndrome and neurodegeneration.

[Pathogenic mechanism and therapies for Gaucher's disease].

Gaucher's disease (GD) also named glucocerebroside lipidosis, is the most common kind of 1ysosomal storage disorder. It results from an autosomal recessive deficiency of the lysosomal enzyme acid ß-glucosidase/ ß-glucocerebrosidase (GBA), which is responsible for hydrolysis of glucocerebroside/glucosylceramide (GlcCer) into glucose and ceramide. Absent or reduced enzymatic activity of GBA leads to multisystemic accumulation of GlcCer in mononuclear phagocyte system and various tissues, such as brain, liver, spleen and so on, causing brain injury, liver splenomegaly, bone damage, the reduction of blood cells and individual growth retardation. GD type I could be treated by enzyme replacement therapy (ERT), but GD types II and III have not effective treatment. In this review, we summarize the recent progress on pathogenic mechanism and therapies in GD.

Glucocerebrosidase deficiency and mitochondrial impairment in experimental Parkinson disease.

Gaucher disease is an autosomal recessive disease, caused by a lack or functional deficiency of the lysosomal enzyme, glucocerebrosidase (GCase). Recently, mutations in the glucocerebrosidase gene (GBA) have been associated with Parkinson's disease (PD) and GBA mutations are now considered the most important genetic vulnerability factor for PD. In this study, we have investigated (i) in vivo whether inhibition of the enzyme glucosylceramide synthase by miglustat may protect C57Bl/6 mice against subchronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication and (ii) in vitro whether a decrease of GCase activity may render dopaminergic neurons susceptible to MPP(+) (1-methyl-4-phenylpyridinium) or alpha-synuclein (α-Syn) toxicity and amenable to miglustat treatment. We could demonstrate that reduction of glucocerebroside by inhibition of glucosylceramide synthase partially protects mice against MPTP-induced toxicity. Conversely, we could show that inhibition of GCase activity with conduritol-B-epoxide (CBE) enhances both α-Syn and MPP(+) induced toxicity in vitro. However, only CBE-induced enhancement of MPP(+) toxicity could be reversed by miglustat. Moreover, we were unable to reveal any alterations of complex I activity or cell respiration upon treatment with either CBE or miglustat. Our findings suggest that the reduction of GCase activity rather than an accumulation of glucocerebroside increases aSyn toxicity.

Gaucher disease: the metabolic defect, pathophysiology, phenotypes and natural history.

Gaucher disease (GD), a prototype lysosomal storage disorder, results from inherited deficiency of lysosomal glucocerebrosidase due to biallelic mutations in GBA. The result is widespread accumulation of macrophages engorged with predominantly lysosomal glucocerebroside. A complex multisystem phenotype arises involving the liver, spleen, bone marrow and occasionally the lungs in type 1 Gaucher disease; in neuronopathic fulminant type 2 and chronic type 3 disease there is in addition progressive neurodegenerative disease. Manifestations of Gaucher disease type 1 (GD1) include hepatosplenomegaly, cytopenia, a complex pattern of bone involvement with avascular osteonecrosis (AVN), osteoporosis, fractures and lytic lesions. Enzyme replacement therapy became the standard of care in 1991, and this has transformed the natural history of GD1. This article reviews the clinical phenotypes of GD, diagnosis, pathophysiology and its natural history. A subsequent chapter discusses the treatment options.

Gaucher disease: a comprehensive review.

Gaucher disease (GD) is an inherited error of metabolism due to a deficiency of glucocerebrosidase. This leads to excessive storage of glucocerebroside in the liver, spleen, bone, and bone marrow. Patients develop anemia, thrombocytopenia, hepatosplenomegaly, bone infarcts, aseptic necrosis of bone, and osteoporosis. There are three types of GD; types 2 and 3 have neurological involvement. With the advent of enzyme replacement therapy and substrate reduction therapy, the natural history of the disease has been has significantly changed, with a marked decrease in morbidity, especially for type 1 patients. This article reviews a broad spectrum of information regarding Gaucher disease, from the history of the disease to newer therapies still in the investigational stage.

Gaucher disease and malignancy: a model for cancer pathogenesis in an inborn error of metabolism.

Clinical observations spanning almost half a century have demonstrated a consistent association of type 1 Gaucher disease (GD1) and cancers. However, the cellular and molecular bases of the association are not understood. Gaucher disease (GD) is a lysosomal storage disorder due to an inherited deficiency of acid ß-glucosidase that underlies the accumulation of glucosylceramide in lysosomes of mononuclear phagocytes and immune dysregulation. The overall cancer risk is markedly increased in GD, and the determinants of malignancy in a subset of patients with GD1 are not known. The association of GD and cancer is most striking for hematological malignancies, with the risk for multiple myeloma estimated at almost 37-fold compared to the general population; some studies have also suggested increased cancer risk for non-hematological malignancies. There is no association of overall severity of GD to risk of cancer, although there is an increased prevalence of splenectomy among patients exhibiting the GD/cancer phenotype. Moreover, there appears to be an increased incidence of multiple consecutive cancers in individual patients. Several factors could contribute to cancer development in GD, including polarization of macrophages to the alternatively activated phenotype, chronic inflammation, chronic B-cell stimulation, splenectomy, hyperferritinemia, lysosomal dysfunction, and endoplasmic reticulum stress. Recent studies have highlighted T-cell dysfunction and modifier genes contributing to an increased cancer risk in GD. Macrophage-targeted enzyme replacement therapy (ERT) reverses systemic features of GD1; while cancer risk appears to be reduced in the era of ERT, it is not known whether this is a direct effect of therapy. Delineation of the mechanisms underlying the increased cancer risk in GD will provide additional novel insights into the role of lipids and macrophages in cancer pathogenesis and, moreover, have the potential to reveal novel therapeutic targets.

Disease state awareness in Gaucher disease: a Q&A expert roundtable discussion.

Gaucher disease is an inherited lysosomal storage disorder caused by mutations in the gene that encodes the lysosomal enzyme glucocerebrosidase. Inadequate enzymatic activity causes cells to become engorged due to an accumulation of glycolipids. Engorged cells then accumulate in various organs, resulting in a range of signs and symptoms. Gaucher disease occurs worldwide but is more common among individuals of Ashkenazi Jewish descent. Approximately 90% of patients with Gaucher disease have non-neuronopathic (type 1) disease, which is characterized by hematologic sequelae, potentially disabling skeletal complications, and late-onset neurologic complications. The other 2 subtypes of Gaucher disease cause neuronopathic disease, with early involvement of the central nervous system. Type 2 Gaucher disease results in death in infancy, while type 3 disease causes variable neurologic manifestations ranging from minimal ocular effects to seizures, ataxia, and cognitive regression. Because of its relative rarity, Gaucher disease often remains misdiagnosed or undiagnosed for some time. However, early diagnosis and appropriate treatment are essential for reducing the risk of complications, improving quality of life, and avoiding inappropriate procedures. Given the prevalence of hematologic manifestations associated with this condition, patients with undiagnosed Gaucher disease may seek treatment from hematologists or oncologists. Therefore, hematology and oncology clinicians need to be aware of the potential for Gaucher disease and consider it in their differential diagnosis.

Lysosomal storage disorders and Parkinson's disease: Gaucher disease and beyond.

Parkinson's disease is associated with mutations in the glucocerebrosidase gene, which result in the enzyme deficiency causing Gaucher disease, the most common lysosomal storage disorder. We have performed an exhaustive literature search and found that additional lysosomal storage disorders might be associated with Parkinson's disease, based on case reports, the appearance of pathological features such as α-synuclein deposits in the brain, and substantia nigra pathology. Our findings suggest that the search for biochemical and cellular pathways that link Parkinson's disease with lysosomal storage disorders should not be limited exclusively to changes that occur in Gaucher disease, such as changes in glucocerebrosidase activity or in glucosylceramide levels, but rather include changes that might be common to a wide variety of lysosomal storage disorders. Moreover, we propose that additional genetic, epidemiological, and clinical studies should be performed to check the precise incidence of mutations in genes encoding lysosomal proteins in patients displaying Parkinson's symptoms.

Gaucher disease: new developments in treatment and etiology.

Gaucher disease (GD) is an autosomal recessive disease which if undiagnosed or diagnosed late results in devastating complications. Because of the heterozygous nature of GD, there is a wide spectrum of clinical presentation. Clinicians should be aware of this rare but potentially treatable disease in patients who present with unexplained organomegaly, anemia, massive splenomegaly, ascites and even cirrhosis of unknown origin. The treatment options for adult type GD include enzyme replacement treatment (ERT) and substrate reduction treatment (SRT) depending on the status of the patient. Future treatment options are gene therapy and "smart molecules" which provide specific cure and additional treatment options. In this review, we present the key issues about GD and new developments that gastroenterologists should be aware of.

Cryptic splice site in the complementary DNA of glucocerebrosidase causes inefficient expression.

The low levels of human lysosomal glucocerebrosidase activity expressed in transiently transfected Chinese hamster ovary (CHO) cells were investigated. Reverse transcription PCR (RT-PCR) demonstrated that a significant portion of the transcribed RNA was misspliced owing to the presence of a cryptic splice site in the complementary DNA (cDNA). Missplicing results in the deletion of 179 bp of coding sequence and a premature stop codon. A repaired cDNA was constructed abolishing the splice site without changing the amino acid sequence. The level of glucocerebrosidase expression was increased sixfold. These data demonstrate that for maximum expression of any cDNA construct, the transcription products should be examined.