Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Sphingolipidoses”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources

[Sphingolipids, vehicle for pathogenic agents and cause of genetic diseases].

Sphingolipids are present in all eukaryotic cells and share a sphingoid base : sphingosine. They were first discovered in 1884 and for a long time they were thought to participate to membrane structure only. Recently it has been established that they are mainly located in particular areas of the membrane called rafts which are signalling platforms. It has also been demonstrated that sphingolipids are receptors and second messengers. They play a crucial role in cellular functioning and are necessary to maintenance and developing of living organisms. However due to their receptor properties, they are also gateway for penetration of pathogenic agents such as virus (Ebola, HIV) or toxins (botulinium, tetanus). These agents first bind to glycosphingolipids or proteins mainly located in rafts. The complex so formed is required for the crossing of the membrane by the pathogenic agent. Sphingolipids metabolism is regulated by numerous enzymes. A failure in the activity of one of them induces an accumulation of sphingolipids known as sphingolipidoses. These are genetic diseases having severe consequences for the survival of the organism. The precise mechanisms of the sphingolipidoses are still mainly unknown which explains why few therapeutic strategies are available. These particular properties of lipids rafts and sphingolipids explain why a growing number of studies in the medical and scientific fields are devoted to them.

Animals↗

[Sphingolipidosis. Recent progress in biochemical diagnosis. New pathogenic approaches].

In an increasing number of biochemical variants of the sphingolipidoses, demonstration of the enzyme defect cannot be achieved by the (briefly summarized) conventional techniques. Alternative methods allowing diagnosis of such patients - in particular metabolic studies in living cell cultures - are discussed. The current knowledge and practical impact of molecular biology in the sphingolipidoses field is shortly reviewed. The authors finally discuss the recent findings highlighting in Niemann-Pick disease type C metabolic abnormalities in the cellular processing of cholesterol and their consequences on diagnosis and pathogenesis of this disorder.

Cells, Cultured↗

Mucolipidosis I.

A case of mucolipidosis I had clinical and histopathologic features that were a combination of changes found in both mucopolysaccharidoses and sphingolipidoses. Corneal clouding, spokelike cataracts, tortuous conjunctival and retinal vessels, and strabismus were clinical findings. Histopathologically, there were inclusion vacuoles similar to those seen in mucopolysaccharidoses; lamellar bodies typical of sphingolipidoses were rare. These vacuoles were seen in conjunctival and corneal epithelium and fibrocytes, conjunctival and retinal vessel endothelium, and all retinal cell layers.

Conjunctiva↗

Sphingolipid metabolism diseases.

Human diseases caused by alterations in the metabolism of sphingolipids or glycosphingolipids are mainly disorders of the degradation of these compounds. The sphingolipidoses are a group of monogenic inherited diseases caused by defects in the system of lysosomal sphingolipid degradation, with subsequent accumulation of non-degradable storage material in one or more organs. Most sphingolipidoses are associated with high mortality. Both, the ratio of substrate influx into the lysosomes and the reduced degradative capacity can be addressed by therapeutic approaches. In addition to symptomatic treatments, the current strategies for restoration of the reduced substrate degradation within the lysosome are enzyme replacement therapy (ERT), cell-mediated therapy (CMT) including bone marrow transplantation (BMT) and cell-mediated "cross correction", gene therapy, and enzyme-enhancement therapy with chemical chaperones. The reduction of substrate influx into the lysosomes can be achieved by substrate reduction therapy. Patients suffering from the attenuated form (type 1) of Gaucher disease and from Fabry disease have been successfully treated with ERT.

Humans↗

Characterization of neutral glycosphingolipids from fetal human brain: evidence for stage-specific expression of the globo, ganglio, and neolacto series in the central nervous system.

Neutral glycosphingolipids were isolated from normal human fetal brains, at 22 to 23 weeks gestation. They were identified as monohexosylceramides, lactosylceramide, and glycolipids belonging to the globo (globotriaosylceramide) and ganglio (gangliotriaosylceramide) series. In addition, considerable amounts of neolactotetraosylceramide and III3-alpha-fucosyl-neolactotetraosylceramide were detected. Although neutral glycolipids of the globo, ganglio, and neolacto series have been demonstrated in the brains of cases with some sphingolipidoses, they are not present in appreciable amounts in differentiated normal brain. Therefore, the present and previous observations would imply that the metabolism of these glycolipid series actively occurs in the normal brain at an early stage of differentiation and continues thereafter in the brain in the case of some sphingolipidoses. The diseased brain is most probably accompanied by a disturbance of differentiation.

Antibodies, Monoclonal↗

Cerebral lipidoses in patients with progressive neurodegeneration: a study from south India.

OBJECTIVE: To study the prevalence and clinical profile of cerebral lipidoses in patients with progressive neurodegeneration. SUBJECTS AND METHODS: A total of 771 patients clinically diagnosed with a progressive neurodegenerative disease were investigated for lipidoses. Specific enzyme assays in serum and leucocytes and other relevant investigations, including histopathology, neuroimaging and neurophysiological studies were conducted when indicated. RESULTS: Fifty-four cases of sphingolipidoses and 1 case of sialidosis type 1 were diagnosed. The sphingolipidoses consisted of 30 cases of metachromatic leukodystrophy, 13 cases of Tay-Sachs disease and its variants, 11 cases of Sandhoff disease, and 1 case each of Niemann-Pick disease and multiple sulphatase deficiency. The clinical features were similar to earlier reports. Parental consanguinity was present in 63.6% of patients. CONCLUSIONS: In south India, where consanguineous marriages are strongly favoured, inherited diseases such as the cerebral lipidoses should be considered when evaluating a patient with progressive neurodegeneration. The establishment of specialised referral centres would provide a helpful approach to the prevention and management of these fatal disorders.

Journal Article↗

Methylamine accumulation in cultured cells as a measure of the aqueous storage compartment in the laboratory diagnosis of genetic lysosomal diseases.

Intracellular accumulation of the lysosomotropic compound [14C]methylamine was used to estimate the size of the lysosomal compartment in fibroblasts cultured from patients with a variety of lysosomal storage diseases. In previous work from our laboratory, it was shown that methylamine accumulation was significantly increased in diseases with infantile or juvenile onset and storage of predominantly water-soluble material such as in the mucopolysaccharidoses, mucolipidoses, and oligosaccharidoses. In the present study, methylamine incorporation was abnormally increased in cells from patients with glycogenosis type II and with Niemann-Pick type C disease, whereas it was normal in other sphingolipidoses and in the late-infantile and juvenile forms of neuronal ceroid lipofuscinoses. The methylamine test was also checked regarding its potential use for prenatal diagnostic testing. In model systems with cultured amniotic or chorionic villus cells, lysosomal storage was experimentally induced by the cathepsin inhibitor leupeptin and was readily detected when compared to untreated controls. Cultured amniotic cells from a fetus with mucopolysaccharidosis II were found to incorporate significantly higher amounts of [14C]methylamine than the normal controls. The results indicate that the methylamine accumulation method is an additional tool in the diagnosis and prenatal diagnosis of lysosomal diseases with abnormal storage of water-soluble material.

Amnion↗

The value of CT in diagnosis and prognosis of different inborn neurodegenerative disorders in childhood.

Inborn errors of metabolism in 40 children have been investigated by computed tomography to obtain data on the degree of cerebral involvement in neurodegenerative and storage disorders: 20 children had various mucopolysaccharidoses, 8 sphingolipidoses , 3 mucolipidoses, 2 oligosaccharidoses , 3 ceroidlipofuscinoses and 4 had various leucodystrophies . Diagnosis in all patients except Alexander's disease was established by biochemical or histological means. The main findings on CT were cerebral atrophy with enlargement of the ventricles and the subarachnoid spaces and hypodensity of the white matter. The degree of cerebral atrophy seemed to develop according to the age of the patients, as could be seen from the patients with mucopolysaccharidosis III, metachromatic leucodystrophy and GM1-gangliosidosis. Hypodensity of the white matter was found in mucopolysaccharidosis I-H, II-B, VI, in mucolipidosis II and in patients with leucodystrophies . On the other hand, there was great variability in these CT findings even in siblings, as seen in four patients with mucopolysaccharidosis VI. Among the series there were several patients who did not show any abnormalities in CT, so that a negative CT did not exclude these disorders, even the leucodystrophies . CT features such as cerebral atrophy or hypodensity were helpful in the evaluation of these disorders, though a diagnosis could not be made by CT alone.

Adolescent↗

A family with combined Farber and Sandhoff, isolated Sandhoff and isolated fetal Farber disease: postnatal exclusion and prenatal diagnosis of Farber disease using lipid loading tests on intact cultured cells.

UNLABELLED: An earlier described patient with combined sphingolipidoses, Farber and Sandhoff disease, had two healthy older brothers and two further sibs, one with Sandhoff disease and one (a fetus) with Farber disease, showing segregation of the respective genes. The prenatal diagnosis in the latter was performed using lipid (sphingomyelin and glucosylceramide) loading tests on the cultured amniotic fluid cells. After 1-3 days of incubation the cells' lipid extract revealed radioactive ceramide to be released and highly accumulated. The deficiency in acid ceramidase was known from the patient with the combined diseases. Confirmation of the prenatal Farber diagnosis was done by similar loading tests on the fetal fibroblasts and by analysis of liver lipids of the less than 18-week-old fetus. CONCLUSION: This is the first report on the use of lipid loading tests on intact cultured cells for prenatal diagnosis of Farber disease. The postnatal diagnosis of Farber disease can also be readily made using those tests, as was shown in four further cases.

Abortion, Eugenic↗

The sphiningolipidoses: an overview.

An outline of the pathways of catabolism of four sphingolipids to ceramide, along with structural details of a few constituents, serves as a framework for better understanding of the sphingolipidoses. The four sphingolipids are sulfatide, sphingomyelin, globoside, and ganglioside GM1. Diseases which can be incorporated into the scheme include Niemann-Pick disease, Gaucher disease, metachromatic leukodystrophy, Krabbe disease, ceramide lactoside lipidosis, Tay-Sachs disease, generalized gangliosidosis, Fabry disease, and Sandhoff disease. Fucosidosis probably also belongs with this group. GM3 (hematoside) sphingolipodystrophy involves blocks in synthetic rather than catabolic pathways.

Galactosylgalactosylglucosylceramidase↗

Biochemistry of glycosphingolipid storage disorders: implications for therapeutic intervention.

The physiological importance of the degradative processes in lysosomes is revealed by the existence of at least 40 distinct inherited diseases, the so-called lysosomal storage disorders. Most of these diseases are caused by a deficiency in a single lysosomal enzyme, or essential cofactor, and result in the lysosomal accumulation of one, or sometimes several, natural compounds. The most prevalent subgroup of the lysosomal storage disorders is formed by the sphingolipidoses, inherited disorders that are characterized by excessive accumulation of one or multiple (glyco)sphingolipids. The biology of glycosphingolipids has been extensively discussed in other contributions during this symposium. This review will therefore focus in depth on (type 1) Gaucher disease, a prototypical glycosphingolipidosis. The elucidation of the primary genetic defect, being a deficiency in the lysosomal glucocerebrosidase, is described. Characterization of glucocerebrosidase at protein and gene level has subsequently opened avenues for therapeutic intervention. The development of successful enzyme replacement therapy for type 1 Gaucher disease is discussed. Attention is also paid to the alternative approach of substrate modulation using orally administered inhibitors of glucosylceramide synthesis. Novel developments about the monitoring of age of onset, progression and correction of disease are described. The remaining challenges about pathophysiology of glycosphingolipidoses are discussed in view of further improvements in therapy for these debilitating disorders.

Animals↗

Sphingolipid metabolism. Sphingoid analogs, sphingolipid activator proteins, and the pathology of the cell.

Sphingolipid metabolism and function was investigated using sphingoid analogs, cells from human sphingolipidoses patients, and knockout animals. Treatment of primary cultured murine cerebellar cells with the structurally modified sphingosine base cis-4 methylsphingosine resulted in decreased sphingolipid biosynthesis accompanied by significant morphological changes. Plasma-membrane-derived glycosphingolipids (GSLs) destined for digestion are internalized through the endocytic pathway and delivered to lysosomes. There, GSLs are degraded by the action of exohydrolases, which are supported, in the case of GSLs with short oligosaccharide chains, by sphingolipid activator proteins (SAPs or saposins). The inherited deficiency of activators give rise to sphingolipid storage diseases. The analysis of cultured fibroblasts from corresponding patients suggests a new model for the topology of endocytosis and lysosomal digestion. Mice with disrupted genes for activator proteins and for GM2 degrading hexosaminidases turned out to be useful models for human diseases.

Animals↗

The inherited neurodegenerative disorders of childhood: clinical assessment.

This review represents an examination of four groups of neurodegenerative diseases, namely the sphingolipidoses, the adrenoleukodystrophy complex, the neuronal ceroid lipofuscinoses, and the sialidoses/sialuria complex. Using a combination of clinical assessment, neuroradiologic appearance, and clinical neurophysiology, one may develop strategies that lead to specific chemical or biochemical determinations for specific diagnoses. In general, disorders of white matter may be distinguished from disorders of gray matter by their appearance on computed tomography and by abnormalities of nerve conduction velocities and auditory brain stem responses. In contrast, disorders of gray matter may be distinguished from disorders of white matter by their appearance on computed tomography and utilization of electroretinography, visual evoked responses, and, to a lesser extent, EEG findings. Where necessary, skin, conjunctival, or nerve biopsy may prove to be useful adjuncts to the diagnosis. Presently, treatment depends on prevention, although aggressive efforts are under way to establish corrective therapy by enzyme replacement. To this end, the use of already existing animal models may prove to be helpful.

Adrenoleukodystrophy↗

Allogeneic hematopoietic cell transplantation for inborn metabolic diseases.

Clinical experience for more than two decades has shown that allogeneic HCT may benefit some but not all patients with inherited metabolic diseases. The HCT procedure is most effective in presymptomatic patients and those with indolent forms of storage diseases but is ineffective in those with overt neurological symptoms or aggressive neonatal or infantile forms. HCT alone does not correct skeletal dysplasia in MPSs and may not prevent development or progression of the peripheral neuropathy in sphingolipidoses and ALD. Decisions regarding HCT in patients with storage diseases should be made by investigators knowledgeable about these diseases, with judicious use of laboratory and clinical resources necessary to reach the best therapeutic decision for the individual patient.

Adrenoleukodystrophy↗

[A program of prevention of hereditary lysosomal diseases in the USSR].

The organization of genetic counselling for the families of patients with lysosomal storage diseases (LSD) was based on the interaction of the genetic counselling units of this country with a laboratory of inherited metabolic diseases of the National Research Center of Medical Genetics, USSR AMS. All the patients from 705 families at risk were examined using biochemical techniques and methods of somatic cell genetics. In total the loci differentiation was performed for 309 patients with mucopolysaccharidoses, glycoproteinoses, mucolipidoses, sphingolipidoses and other LSD. 53 families at risk (of 277) were prenatally diagnosed. 66 fetuses were diagnosed for mucopolysaccharidoses, type I, II, III, A and B, VI, Tay-Sachs disease, Sandhoff's disease, GM1-gangliosidosis, metachromatic leukodystrophy, mannosidosis, and multiple sulfatidosis. In total 18 affected fetuses were diagnosed and aborted. All the prenatal diagnoses were verified. The prevalence of mucopolysaccharidoses in two Central Asian republics was evaluated as 1:15,000. An Uneven ethnic distribution of different mucopolysaccharides in the USSR has also been shown.

Female↗

Lysosomal storage diseases in Greece.

Over the last 13 years 2745 patients from all over Greece suspected to have a lysosomal storage disorder were referred to the Institute of Child Health. 1581 of those were suspected of having a mucopolysaccharidosis (MPS). 94 cases (3.42% of the total referrals) were positive: 36 patients with MPS, 6 with mucolipidosis (1 type I, 1 type II and 4 type III) and 3 with mannosidosis. Sanfilippo B was not only the most frequent type III MPS but also the most frequent MPS identified in our study. Sphingolipidoses and other lysosomal disorders were diagnosed in 47 cases and non-lysosomal disorders in 19 cases. In our experience Gaucher disease, Sanfilippo B and Hunter syndrome are the most frequent lysosomal disorders in Greece accounting for 23.4%, 17.0% and 7.6% respectively of all diagnosed cases. 13% of the patients originated from Thessaly including 5/16 Sanfilippo B, 2/3 Morquio B, 2/3 Maroteaux-Lamy, 2/6 Metachromatic leukodystrophy and 2/12 Gaucher type 1.

Greece↗

Life-threatening splenic hemorrhage in two patients with Gaucher disease.

Massive splenomegaly is a frequent finding in patients with Gaucher disease, the most common of the sphingolipidoses. Even so, the risk for splenic rupture and intracapsular hemorrhage has not been emphasized due to the rarity of this occurrence and the fibrotic, rubbery consistency of splenic tissue in these patients. We report two adult patients with type 1 Gaucher disease who suffered life-threatening splenic bleeds that were not acutely diagnosed. Both patients ultimately required emergent splenectomies. Factors complicating the diagnosis of splenic hemorrhage in patients with Gaucher disease are discussed. Published 2000 Wiley-Liss, Inc.

Adult↗

Possible role for protein kinase C in the pathogenesis of inborn errors of metabolism.

Protein kinase C (PKC) is a ubiquitous enzyme family implicated in the regulation of a large number of short- and long-term intracellular processes. It is hypothesized that modulation of PKC activity may represent, at least in part, a functional link between mutations (genotype) that lead to the pathological accumulation of naturally occurring compounds that affect PKC activity and perturbation of PKC-mediated substrate phosphorylation and cellular function in the corresponding diseases (phenotype). This model provides a unifying putative mechanism by which the phenotypic expression of some inborn errors of metabolism may be explained. Recent studies in a cell-free system of human skin fibroblasts support the hypothesis that alteration of PKC activity may represent the functional link between accumulation of sphingolipids and fatty acyl-CoA esters, and perturbation of cell function in sphingolipidoses and fatty acid oxidation defects, respectively. Further studies will elucidate the effects of these alterations on PKC-mediated short- and long-term cellular functions in these diseases, as well as the possible role of PKC in the pathogenesis of other diseases.

Fatty Acids↗