Drug-induced intralysosomal storage of sulfated glycosaminoglycans (GAGs): a methodical pitfall occurring with acridine derivatives

The present communication deals with an adverse drug action which is exerted by a series of dicationic amphiphilic compounds such as the immunomodulatory drug tilorone and congeners. The drugs induce lysosomal storage of sulfated glycosaminoglycans (GAGs) in intact organisms and in cultured cells by impairing the lysosomal GAG degradation. This impairment was proposed to be due to the formation of non-degradable GAG-drug complexes. GAGs are highly water-soluble and not preservable by aldehyde fixatives. Therefore, usually the lysosomes appear optically empty in histological preparations, unless the fixative is supplemented with a GAG-precipitating agent. When acridine derivatives were used for the induction of GAG-storage, the lysosomal storage material displayed unexpected and unsystematic variability with regard to its preservability and ultrastructure. In the present study, evidence is presented that the acridine derivatives (a) remain bound to the stored GAGs for some time after glutaraldehyde fixation; and (b) they precipitate GAGs in vitro. Thus, apart from their unwanted action in the living cell, i.e., disturbing lysosomal GAG-degradation, the drugs function as precipitants and "fixatives" for the intralysosomal GAGs. The uncontrolled persistence of the drugs after tissue fixation leads to variable degree of GAG-preservation and thus to unpredictable variability of the ultrastructure of the storage lysosomes. If this pitfall is not realized, the resulting inconsistencies may rise confusion among toxicologic pathologists who deal with drug-induced lysosomal storage disorders.

Reversible rearrangement of vimentin-type intermediate filaments in cultured human skin fibroblasts from patients with lysosomal storage diseases

Immunofluorescence microscopy shows that unlike cytoplasmic microtubules (MT), vimentin-type intermediate filaments (IF) are collected into ring-shaped structures in affected fibroblasts. The altered IF organization could be observed in monolayers of polarized fibroblasts in the prolonged stationary growth phase and-after replating-upon their initial spreading. Transition from a discoid to an extended cellular form is accompanied by centrifugal dislocation of ring-shaped IF structures towards the cell's active edge with gradual restoration of the radial fibrillar vimentin network. Spreading of affected cells occurred more slowly than that of control fibroblasts.

Lectin histochemistry of infantile lysosomal storage disease associated with osteopetrosis

In infantile lysosomal storage disease associated with osteopetrosis the nature of the enzyme deficiency as well as the type of material accumulated are both unknown. We used lectin histochemistry to characterize the storage material of previously reported cases. Using paraffin sections neurons stained positively with Luxol fast blue (LFB), periodic acid-Schiff (PAS), Concanavalia ensiformis agglutinin, Datura stramonium agglutinin, Griffonia simplicifolia-I, Lens culinaris agglutinin, Ricinus communis agglutinin-I, succinylated wheat germ agglutinin and wheat germ agglutinin, indicating an accumulation of fucosylated N-glycosidically linked oligosaccharides containing beta- and alpha-galactosyl residues and compounds containing N-acetyllactosamine. Reticuloendothelial cells in liver and in spleen did not stain with LFB, but did stain with PAS and the above lectins. These results indicate that there is storage of both carbohydrates and lipids in neurons, and stored carbohydrates with similar residues in reticuloendothelial cells in this disease, where the primary defect is still unknown.

Bone marrow cytological storage phenomena in lipidoses

The bone marrow cytological storage phenomena in generalized lysosomal lipid storage disorders (Gaucher disease, Niemann-Pick disease, GM1-gangliosidosis, cholesterol ester storage diseases) are reviewed. The value of bone marrow cytology as a pre-screening method in the diagnostic strategy for the different diseases depends on the disease type suspected and the availability of biochemical screening methods. While cytological screening is not necessary in certain patients with typical clinical pictures, it may prove undispensable in others.

The biochemistry and clinical features of galactosialidosis

Galactosialidosis is a heterogeneous disorder that is manifested in infantile, late infantile, juvenile/adult, and atypical forms. In every instance the primary defect is in the ability of protective protein to associate with beta-galactosidase and neuraminidase to protect them from intralysosomal proteolysis. The protective protein is in reality a serine protease that displays both cathepsin A and C-terminal deamidase activity. We summarize the major clinical features of each form, and the range of storage products accumulated. The concept of an intralysosomal complex containing beta-galactosidase and neuraminidase in addition to protective protein seems irrefutable but major gaps exist in our understanding of how the complex is formed and in what subcellular organelles, how it is sustained, and the protein domains contributed by the constituent enzymes that play a pivotal role in this process.

Ultrastructure of human dermal mast cells in 29 different lysosomal storage diseases

The effect of lysosomal storage diseases on the ultrastructure of human mast cells has not previously been reported. Indeed, there has been little published evidence indicating that mast cells contain typical lysosomes. However, mast cell cytoplasmic granules contain hydrolases similar to those found in lysosomes, but which differ from lysosomal hydrolases in exhibiting optimal activity at higher pH. We therefore examined by transmission electron microscopy the dermal mast cells in 58 biopsies of patients exhibiting 1 of 29 different lysosomal storage diseases. We found mast cells containing abnormal lysosomes in 16 of these disorders. In 6 of these 16 diseases, the mast cells' cytoplasmic granules appeared normal. These observations indicate that human mast cells can contain lysosomes, and provide evidence that the enzymes affected by lysosomal storage diseases are active in mast cells.

Adult-onset lysosomal storage disease in a Schipperke dog: clinical, morphological and biochemical studies

An adult-onset lysosomal storage disorder was diagnosed in a 5-year-old Schipperke dog with progressive cerebellar and central vestibular signs. It was characterized by cerebellar atrophy with extensive loss of Purkinje and granular cells, and hydrocephalus. Enlarged and vacuolated neurons were observed in spinal cord and brain; pancreatic centrolobular and islet cells were also vacuolated. Ultrastructurally, enlarged secondary lysosomes laden with lamellated membrane structures were present in neurons and empty enlarged vacuoles were found in pancreatic centroacinar, ductal, and islet cells. On frozen sections neurons stained with Ricinus communis agglutinin-I and wheat germ agglutinin. On paraffin sections neurons stained with luxol fast blue, periodic acid-Schiff, Concanavalia ensiformis agglutinin, and were autofluorescent. These findings indicate an accumulation of glycolipids containing terminal beta-galactosyl and alpha-sialyl residues, and N-linked oligosaccharides. Tissue activity of lysosomal beta-galactosidase was 50% of normal and the activity of beta-hexosaminidase was elevated. Brain lipid-bound sialic acid was twice normal, with a small increase of GM1-ganglioside, but there was a significant elevation of GM2 (GD2) and GM3 (GD3). In addition, significant elevations of sialylated and non-sialylated oligosaccharides were noted. These clinical, biochemical and pathological findings are similar to those observed in human patients with adult-onset galactosialidosis.

Infantile galactosialidosis presenting with congenital adrenal hyperplasia and renal hypertension

A patient with early infantile galactosialidosis presenting as congenital adrenal hyperplasia with clitoral hypertrophy and arterial hypertension is reported. Serum 17-alpha-OH-progesterone and plasma renin levels were elevated. Adrenal hyperplasia and thickening of the cardiac septum were detected by sonography; however, progressive hepatosplenomegaly, increasingly coarse features, and vacuolization of bone marrow and liver cells suggested a storage disorder. Combined deficiency of beta-galactosidase and sialidase enzyme activity in both lymphocytes and cultured fibroblasts was detected. This patient with early infantile galactosialidosis is the first reported who presented with congenital adrenal hyperplasia.

GM2D gangliosidosis B1 variant in a boy of German/Hungarian descent

After the introduction of 4-methylumbelliferyl-2-acetamido-2-deoxy-beta A-D-glucopyranoside (4MUG) and its sulfated form (4MUGS) in the pre- and postnatal diagnosis and carrier identification of gangliosidosis genotypes, infrequent forms of the GM2 gangliosidosis Type B (Tay-Sachs disease) have been observed which show normal activity of Hexosaminidase A (Hex A) isoenzyme with the substrate 4MUG but absent or deficient activity against the sulfated form 4MUGS. Here we report the observation of a German/Hungarian boy aged 12 when he died with a prolonged course of a neurodegenerative disorder, later biochemically identified as a GM2 gangliosidosis B1-variant which is characterized by a deficient Hex A activity only against 4MUGS. The first clinical symptoms had occurred after the age of 14 months with a clear manifestation of the disease at age 3, when he presented disturbances of movement and tended to fall down. The slowly progressive course with brain atrophy, seizures and severe mental deterioration resulted in death after almost 9 years. At autopsy, the typical light microscopic neuronal changes of a "lysosomal storage disorder" were found, with multilamellar concentric bodies (MCB) and Zebra bodies in the neuronal cytoplasm at the electron microscopic level.

Conjunctival biopsy in adult form galactosialidosis

Conjunctival biopsy was performed in two siblings with adult-form galactosialidosis. Electron microscopically, several types of intracytoplasmic inclusion were observed in the fibroblasts in conjunctival stroma, lymphatic capillary endothelial cells, Schwann cells, and epithelial cells. Membrane-bound vesicles with fibrillogranular content were frequently observed, and occasional lamellar structures were noted in these inclusions. Dense granular inclusions and oil droplets were also seen. Dense granular inclusions have not been reported in this disease previously.

Adult onset lysosomal storage disease in a Tibetan terrier: clinical, morphological and biochemical studies

We describe a novel late-onset lysosomal lipid storage disease affecting a Tibetan terrier. The principal clinical manifestations include visual loss, progressive cerebellar ataxia and dementia. A necropsy of an affected 10-year-old dog demonstrated cerebellar atrophy. Histological analysis revealed extensive loss of retinal ganglion cells and cerebellar Purkinje cells, and mild to moderate loss of neurons in the cerebrum, basal ganglia and spinal cord. There were generalized neuronal hypertrophy and multifocal neuronal necrosis associated with the presence of enlarged macrophages. Neurons and perineuronal macrophages contained cytoplasmic granules that stained with PAS, luxol fast blue and several lectins. The granules were sudanophilic and autofluorescent. Electron microscopic analysis revealed lysosomes laden with lamellated membrane structures in neurons, pancreatic ductal and centroacinar cells and in cultured fibroblasts. These findings indicate lysosomal storage of both lipid and carbohydrate. Biochemical analysis of brain lipids and numerous lysosomal enzyme assays of leukocytes and cultured fibroblasts were unsuccessful in elucidating the underlying enzyme defect, although a generalized increase of brain gangliosides was noted.

Dementia, myoclonus, peripheral neuropathy, and lipid-like material in skin biopsy during psychotropic drug treatment

Chronic treatment of humans with several drugs is associated with lesions resembling lipidosis in different tissues. Recently, a Creutzfeldt-Jacob-like syndrome has been observed during tricyclic antidepressant therapy, but no evidence of interaction of these drugs with lysosomal function has been reported during such treatment. We report a case of dementia, myoclonus, peripheral neuropathy, and lipid storage in the skin due to antidepressant drug therapy, in which the discontinuation of drugs resulted in an improvement of clinical and electrophysiologic signs together with reduction of morphological evidence of lipid lysosomal storage.

Dysmyelinogenesis in animal model of GM1 gangliosidosis

Magnetic resonance imaging (MRI), pathologic examinations, and biochemical analyses were performed on 2 different canine mutants with GM1 gangliosidosis (i.e., English Springer Spaniel and Portuguese Water Dog) and on age- and sex-matched controls. Serial MRI studies were also performed on a child with infantile-onset GM1 gangliosidosis. The affected dogs had abnormalities on MRI, including a relative increase in gray matter and an abnormal signal intensity of cerebral and cerebellar white matter observed on T2-weighted MRI. White matter changes on MRI were similar to white matter abnormalities observed in a 15-month-old boy with GM1 gangliosidosis. The weight ratio of white to gray matter from the frontal lobe was markedly reduced. Microscopic examination revealed characteristic ballooned neurons which stained lightly with Luxol-fast blue. The central cerebral and cerebellar folia white matter exhibited pallor and gliosis, while the corpus callosum and fornix stained normally with Luxol-fast blue. Axons appeared intact on Bodian staining. Ultrastructural studies revealed fewer myelinated axons in affected puppies. Total gangliosides in gray matter were elevated. Thin-layer chromatography demonstrated GM1 ganglioside as the predominant ganglioside. The amount of cerebrosides and sulfatides was reduced in the gray and white matter when compared to controls but the ratio in gray and white matter remained unchanged. Immunostaining of neutral glycolipids disclosed increased amounts of stage-specific embryonic antigen-1 glycolipid in gray matter. These findings suggest that canine models for GM1 gangliosidosis are associated with abnormal myelin development which may be similar to the human disease.

Imipramine induced lipidosis and dexamethasone effect: morphological and biochemical study in normal and chronic GM2 gangliosidosis fibroblasts

A large heterogeneous group of lysosomotropic compounds with a common cationic amphiphilic structure induces in vitro and in vivo lysosomal lipid storage. The biochemical mechanism underlying the lipidosis is still the subject of investigation. The authors report the experimental effect of imipramine and dexamethasone on lysosomal system in cultured skin fibroblasts. Morphological and ultrastructural observations of cells treated with imipramine showed vacuoles with lipidic storage, enlarged lysosomes with electron translucent zones and normal appearance of all the other cytoplasmic organelles. The lysosomal enzyme activities were decreased on biochemical study. On the contrary, an increased enzyme activity was detected in the culture medium. Pretreatment with dexamethasone partially prevented the effect of imipramine. Our results suggest that tricyclic antidepressants may induce lysosomal lipidosis through a dysfunction in the recycling of mannose-6-phosphate receptors and in the trafficking of newly synthesized lysosomal enzymes. Moreover the data presented may provide a clue in understanding some of the side effects observed in patients chronically treated with antidepressant drugs.

Morphometric studies of pancreatic acinar granule formation in NCTR-Balb/c mice

NCTR-Balb/c mice are afflicted with a cholesterol lysosomal storage disorder stemming from a defect in intracellular cholesterol processing. The clinical and biochemical abnormalities expressed in the mice resemble Niemann-Pick type C and D disorders in humans. One of the proposed mechanisms to explain the pathophysiology of the disorder implies a defect in the process of membrane transport that normally takes place in the vesicular movement of cholesterol to specific target sites in the cell. Secretory granule formation in pancreatic acinar cells is one of the biological processes known to involve massive membrane flow. Thus, we have undertaken a morphometric study of the regranulation mechanism in the pancreatic acinar cells of the mutant mice, as a way of studying cellular membrane movement. Electron micrographs of pancreatic acinar cells from mutant and normal mice were taken at several time points after extensive degranulation induced by pilocarpine injection. Two hours after stimulation the pancreatic cells demonstrated a complete loss of granules, and at later time points newly formed granules appeared. Identical unit granule volumes were observed in both groups, indicating that the progranules were of normal size. However, the rate of granule formation and maturation was reduced in the mutant mice, which might be the result of a defect in membrane function.

Farber disease: an ultrastructural study. Report of a case and review of the literature

A case of Farber disease is reported and the ultrastructural pathology of the disease is reviewed. The present case showed the typical clinical picture of Farber disease. Acid ceramidase deficiency was demonstrated biochemically. Ultrastructural features of one subcutaneous nodule and a skin biopsy are described. Three lysosomal inclusions characterize Farber disease: curvilinear tubular bodies observed mainly in the reticuloendothelial system, "banana bodies" recorded only in the peripheral nervous system and zebra-like bodies which are essentially a neuronal storage. The nature of each is discussed and the skin biopsy is emphasized for its important diagnostic interest.

Muscular involvement in lysosomal acid lipase deficiency in rats

We investigated the pathological and biochemical changes of skeletal muscle in rats with lysosomal acid lipase deficiency, which is an animal counterpart of human Wolman's disease. In the affected rats, the acid lipase activity for three different substrates, 4-methylumbelliferyl-oleate (18.9% of the normal control level), [14C]cholesteryl oleate (23.5%), and [14C]triolein (26.9%), was similarly decreased in the lysosomal fraction of skeletal muscle which was obtained by differential centrifugation. Histochemical studies showed that acid phosphatase activity was high in the endomysium and perimysium and in some muscle fibers. Some fibers showed vacuolar degeneration resembling "rimmed vacuoles". Ultrastructural studies demonstrated many membrane-bound lipid droplets in the muscle fibers, especially in the subsarcolemmal space, indicating that a low density lipoprotein (LDL) uptake pathway apparently existed in the muscle cells. However, such lipid accumulation was much greater in the interstitial cells and the endothelial cells. This distribution also suggests that LDL/cholesterol is supplied to muscle cells predominantly through endothelial cells.

[Changes in the organization of the intermediate filament system of human fibroblasts in lysosomal storage diseases and their modeling]

The organization of the system of the vimentin intermediate filaments (IFs) in human fibroblasts in lysosomal storage diseases (Fabry's disease, mannosidosis) and their modelling has been studied in vitro. It was shown that during accumulation of nonhydrolyzable compounds, hypertrophy of the lysosomal compartment is accompanied by formation of ring-shaped bundles IFs, surrounding apparently these increased organelles. The changed organization of IFs is characteristic of polarised pathological cells in monolayer, and after repassage it is retained only at the spreading state; on transition from the discoid to extended cellular form there occurred the centrifugal shift of ring-shaped structures of IFs to active cell border and gradual restoration of radial fibrillar state of IFs. It is suggested that on intralysosomal storage of unsplit compounds reorganization of the vimentin-type IFs in ring-shaped structure is necessary for optimal distribution and stabilization into the cytoplasm of large amounts of increased lysosomes with exo- and endogenous contents. In condition of free spreading (i. e. with diminished cell density) the restoration of normal fibrillar IF organization may be due to the loss of considerable number of hypertrophied lysosomes; the involvement of lysosomal membrane in formation of active cellular border is not to be ruled out.

Subcellular localization of acid carboxypeptidase in rat liver and human fibroblasts

The subcellular distribution of acid carboxypeptidase was investigated in rat liver, normal human skin (CRL 1501) and lung (WI-38) fibroblasts, galactosialidosis skin fibroblasts (GM 00806) and transformed lung fibroblasts (WI-38 VA 13). Results of differential and isopycnic centrifugations and osmotic activation experiments clearly indicate that the enzyme is located in lysosomes, in agreement with observations suggesting that carboxypeptidase is the protective protein of the 'Galjaard complex' which is defective in galactosialidosis.

Caprine beta-mannosidosis: regional differences in deficits of CNS myelin proteins

Caprine beta-mannosidosis is an autosomal recessive disorder characterized by marked deficiency of beta-mannosidase activity, accumulation of oligosaccharides, and pathologic changes involving prominent dysmyelination. The myelin deficits show marked regional variation, with spinal cord mildly affected and many brain regions severely affected by morphologic criteria. In this study, levels of myelin basic protein (MBP) and proteolipid protein (PLP) were measured by immunoblotting in samples prepared from spinal cord, brainstem and cerebral hemispheres of normal and affected goats at 2-4 days (newborns) and 2-4 weeks of age. In affected goats, total levels of MBP in spinal cord were normal, while PLP levels were 60-70% of normal at both ages. In contrast, PLP and MBP in brainstem and cerebral hemispheres were severely decreased at both ages, with levels of PLP 10-13% and MBP 25-29% of normal in newborns, and generally more reduced at 2-4 weeks. When myelin fractions were isolated on 0.32/0.85 M sucrose gradients, yields were about 38 and 25% of normal in spinal cord at the two ages, but less then 3% of normal in brainstem. Yields of myelin-like fraction were decreased as well, but to lesser extents than yields of myelin. Myelin from spinal cord had a normal composition with regard to PLP and MBP content, while the myelin fraction from brainstem was markedly deficient in both proteins. This suggests formation of myelin with a very abnormal composition in brainstem, or inclusion of large amounts of membranes other than myelin in this fraction. The more severe deficits in brainstem and cerebral hemispheres compared to spinal cord are consistent with morphologic observations.(ABSTRACT TRUNCATED AT 250 WORDS)

The ultrastructural spectrum of lysosomal storage diseases

After the important advances that have been made in the diagnosis of inherited lysosomal disorders with the help of biochemical-enzymic methods, the importance of electron microscopy for the identification and study of these conditions has apparently declined. Nevertheless, numerous specimens continue to be submitted for ultrastructural examination when lysosomal storage diseases are suspected. The article summarizes the present role of electron microscopy in this area and depicts typical specific findings in comparison with suggestive and nonspecific lysosomal changes. It is concluded that ultrastructural examination remains a useful and occasionally compulsory diagnostic method. In addition, it contributes to the identification of new diseases, the study of animal models of storage diseases, and the assessment of novel therapeutic methods such as bone marrow transplantation.

Niemann Pick c or storage by excessive blood cell destruction: a case presenting a diagnosis problem

A case of storage disease followed up during 12 a was studied by morphological, histochemical, immunological, and biochemical techniques. Data were analysed in an attempt to differentiate an acquired storage by excessive cell degradation from a storage of genetic origin. If, as it is our belief, a conclusion of acquired storage can be made, this observation in which the same cholesterol metabolism abnormalities as in Niemann Pick type C were seen, leads to a rediscussion of their diagnostic significance.

Ultrastructural lesions of ovine GM1 gangliosidosis

Ovine GM1 gangliosidosis, an inherited disease of sheep with deficiencies of beta-galactosidase and alpha-neuraminidase, storage of GM1 ganglioside, asialo-GM1 and neutral long chain oligosaccharides in the brain, autosomal recessive inheritance, and histopathologic lesions typical of lysosomal storage diseases, has been described recently. Selected tissues from two sheep with the condition and an age-matched control were examined by transmission electron microscopy to characterize the ultrastructural lesions. In all central and peripheral neurons, the majority of the cytoplasmic space was occupied by membrane-limited enlarged bodies judged to be lysosomes, with a resultant displacement of normal organelles. The neuronal lysosomes usually contained stacks and concentric whorls of lamellae of stored material with a periodicity of 25 to 75 nM. Individual lamellae consisted of fine, multilayered (three to 10, and occasionally more) bands. Less commonly, enlarged neuronal lysosomes contained fibrillogranular or electron dense material. Central nervous system microglia and peripheral nervous system satellite cells had less extensive storage of similar material within enlarged lysosomes, whereas oligodendrocytes, astrocytes, and Schwann cells were relatively unaffected. Hepatocytes and renal epithelial cells also had storage of less quantity than neurons, but within even larger lysosomes. In contrast to neuronal storage material, visceral storage consisted of vesicles containing fibrillogranular or electron dense material within a mostly electron lucent matrix with only occasional lamellae. Kupffer cells and macrophages from bone marrow were affected similarly to but less severely than hepatocytes and renal epithelial cells, whereas hematopoietic cells and chondrocytes were unaffected. Both neuronal and visceral storage were evident, but the neuronal storage was much more extensive.(ABSTRACT TRUNCATED AT 250 WORDS)