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Previous studies have suggested that arylsulphatase A (ASA) deficiency may be present in psychiatric patients. A number of patients with low ASA activity and various neuropsychiatric symptoms have been observed. Metachromatic leucodystrophy (MLD) is a disease caused by deficiency of the enzyme ASA. Clinically, adult MLD may present as a schizophrenia-like psychosis, deterioration of cognitive functions, personality changes, depression and dementia. However, there are individuals with low ASA activity without clinical symptoms of MLD. This state is described as ASA pseudodeficiency. It remains controversial whether low ASA activity predisposes to or influences the development of psychiatric symptoms. Relatively little attention has been paid to the role of neurodegenerative processes in the pathophysiology of psychiatric disorders. The hypothesis underlying this work is that there is a subclass of mentally ill patients whose psychiatric problems are at least partly caused by an abnormal ASA. The purpose of this particular study was to determine whether an abnormal ASA could be detected in schizophrenic, major depressed and demented patients and control subjects. There were 66 schizophrenic, 59 major depressed and 61 demented patients. The control group consisted of 102 healthy volunteers. Leucocyte ASA activity was determined from blood samples, using p-nitrocatechol sulphate as substrate. Our results show that low ASA activity is more frequently found in psychiatric patients than in control subjects. Our findings indicate that clinical types of major depression and schizophrenia could be connected with low ASA activity. The presence of a decreased ASA activity points to the conclusion that an enzyme deficit entails vulnerability to psychiatric disorders., (Copyright 2001 S. Karger AG, Basel)

The expression of neutral glycosphingolipids and gangliosides has been studied in human skeletal and heart muscle using indirect immunofluorescence microscopy. Transversal and longitudinal cryosections were immunostained with specific monoclonal and polyclonal antibodies against the neural glycosphingolipids lactosylceramide, globoside, Forssman glycosphingolipid, gangliotetraosylceramide, lacto-N-neotetraosylceramide and against the gangliosides GM3(Neu5Ac) and GM1(Neu5Ac). To confirm the lipid nature of positive staining, control sections were treated with methanol and chloroform:methanol (1:1) before immunostaining. These controls were found to be either negative or strongly reduced in fluorescence intensity, suggesting that lipid bound oligosaccharides were detected. In human skeletal muscle, lactosylceramide was found to be the main neutral glycosphingolipid. Globoside was moderately expressed, lacto-N-neotetraosylceramide and gangliotetraosylceramide were minimally expressed and Forssman glycosphingolipid was not detected in human skeletal muscle. The intensities of the immunohistological stains of GM3 and GM1 correlated to the fact that GM3 is the major ganglioside in skeletal muscle whereas GM1 is expressed only weakly. In human heart muscle globoside was the major neutral glycosphingolipid. Lactosylceramide and lacto-N-neotetraosylceramide were moderately expressed, gangliotetraosylceramide was weakly expressed and the Forssman glycosphingolipid was not expressed at all in cardiac muscle. GM3 and GM1 were detected with almost identical intensity. All glycosphingolipids were present in plasma membranes as well as at the intracellular level.

In this study, brain gangliosides in prenatal and postnatal human life were analyzed. Immunohistochemically, the presence of "c"-pathway of gangliosides (GQ1c) in embryonic brain was only recorded at 5 weeks of gestation. Biochemical results indicated a twofold increase in human cortex ganglioside concentration between 16 and 22 weeks of gestation. The increasing ganglioside concentration was based on an increasing GD1a ganglioside fraction in all regions analyzed except cerebellar cortex, which was characterized by increasing GT1b. In this developmental period, GD3 was found to be localized in the ventricular zone of the cortical wall. After birth, GD1b ganglioside in neuropil of granular cell layer corresponding to growing mossy fibers was expressed in cerebellar cortex. Between birth and 20/30 years of age, a cerebral neocortical difference of ganglioside composition was observed, characterized by lowest GD1a in visual cortex. Analyzing the composition of gangliosides in cortical regions during aging, they were observed to follow region-specific alterations. In frontal cortex, there was a greater decrease in GD1a and GM1 than in GT1b and GD1b, but in occipital (visual) cortex there was no change in individual gangliosides. In hippocampus, GD1a moderately decreased, whereas other fractions were stable. In cerebellar cortex, GD1b and GT1b fractions decreased with aging.

The administration of aluminum (Al) to uremic rats leads to Al accumulation in different brain regions with subsequent alteration of brain gangliosides. Addition of 24R,25-dihydroxyvitamin D3[24R,25-(OH)2D3] did not influence the brain Al content determined by plasma argon emission spectrometry, but prevented the decrease in brain gangliosides. By using electron microscopy and laser microprobe mass analysis, it was demonstrated that in rats given 24R,25-(OH)2D3 together with Al, the metal was mainly kept within perivascular astrocytes of the blood-brain barrier. On the contrary, in rats given Al only, the metal was evenly distributed throughout the brain areas causing extensive demyelination, chromatolysis of nerve cells in some brain regions (hippocampus) and brain edema. Our results could find application in the prevention of Al-induced encephalopathy in patients on hemodialysis.

In Alzheimer's disease, all ganglio-series gangliosides (GM1, GD1a, GD1b and GT1b) were found to be decreased in temporal and frontal cortex, and nucleus basalis of Meynert. In addition, in Alzheimer's disease simple gangliosides (GM2, GM3) were elevated in frontal and parietal cortex, possibly correlating to accelerated lysosomal degradation of gangliosides and/or astrogliosis occurring during neuronal death.

Simultaneous profile determination and quantification of human cerebrospinal fluid (CSF) gangliosides in various neurologic diseases (n = 71) was examined. Gangliosides were extracted with methanol/chloroform from clinically available amounts of CSF (4-5 ml), then separated and quantified by high-performance thin-layer chromatography (HPTLC) and direct densitometry. Based on chromatographic comparison with standards, the percentage of lipid-bound NeuAc positive fractions in 'normal' CSF samples were: GM1 (II3 NeuAc-GgOse4Cer) (3%); GD3 (II3 NeuAc2-Lac-Cer) (4%); GD1a (IV3 NeuAc, II3 NeuAc-GgOse4 Cer) (15%); X1 (3%); GD1b (II3(NeuAc)2-GgOse4 Cer) (16%); X2 (4%); GT1b (IV3 NeuAc, II3(NeuAc)2-GgOse4-Cer) (40%); and GQ1b (IV3(NeuAc)2, II3(NeuAc)2-GgOse4-Cer (15%). Similarity between CSF and CSF and human cerebellar cortex, particularly in proportion of "b" series gangliosides (GQ1b, GT1b, GD1b), could be observed. A higher proportion of GD1a ganglioside, with decreased GQ1b was found in infancy. The total ganglioside content (mean +/- 2 SD) varied between 645-894 micrograms/l. Significant alterations of the CSF ganglioside profile, with an increase in less polar gangliosides, GM3 and GD3, correlated with the blood-brain barrier dysfunction (CSF hemorrhages, compressive syndrome), or some malignant processes (metastatic brain melanoma). A statistically significant increase in the content of total CSF gangliosides was found in the following groups of patients as compared to controls: (1) ischemic cerebrovascular accident (CVI) with good outcome (P less than 0.02); (2) peripheral neuropathy and polyneuropathy (P less than 0.001) and (3) intravertebral discopathy (P less than 0.05). A significant decrease in the content of total CSF gangliosides was found in CVI group with lethal outcome (P less than 0.05).

In this study, brain gangliosides in prenatal and postnatal human life and Alzheimer's disease were analyzed. Immunohistochemically, the presence of the "c"-series of gangliosides (GQ1c) was only registered in the embryonic brain at 5 weeks of gestation. Biochemical results indicated a two-fold increase in ganglioside concentration in the human cortex between 16 and 22 weeks of gestation. The increasing ganglioside concentration was based on an increasing GD1a ganglioside fraction in all regions analyzed except in the cerebellar cortex, which was characterized by increasing GT1b. During prenatal human development, regional differences in ganglioside composition could only be detected between the cerebrum ("a"-pathway) and the cerebellum ("b"-pathway). Between birth and 20-30 years of age, a cerebral neocortical difference of ganglioside composition occurred, characterized by the lowest GD1a in visual cortex. Analyzing the composition of gangliosides in cortical regions during aging, they were observed to follow region-specific alterations. In the frontal cortex, there was a greater decrease in GD1a and GM1 than in GT1b and GD1b, but in the occipital (visual) cortex there was no change in individual gangliosides. In hippocampus, GD1a moderately decreased, whereas other fractions were stable. In the cerebellar cortex, GD1b and GT1b fractions decreased with aging. In Alzheimer's disease, we found all ganglio-series gangliosides (GM1, GD1a, GD1b, GT1b) to be decreased in regions (temporal and frontal cortex and nucleus basalis of Meynert) involved in pathogenesis of disease. In addition, in Alzheimer's disease we found simple gangliosides (GN2, GM3) to be elevated in the frontal and parietal cortex, which might correlate accelerated lysosomal degradation of gangliosides and/or astrogliosis occurring during neuronal death.

In this study, brain gangliosides of patients with Alzheimer's disease (AD, N = 5) were analyzed and compared with control human brains (C, N = 3). Gangliosides were analyzed in seven brain regions: cerebral cortex (frontal, parietal, temporal and occipital), hippocampus, basal telencephalon and frontal white matter. The results demonstrated gangliosides to be decreased in the majority of regions analyzed, however, a significant decrease in gangliosides (nmol LBSA/mg proteins or g fresh weight) in frontal cortex and white matter (P less than 0.05) was recorded. When gangliosides were expressed in nmol LBSA/mg DNA (deoxyribonucleic acid), their basal telencephalon, suggesting that high astroglial proliferation might have concealed the real neuronal degeneration. In the ganglioside composition, all human brain regions contained moderately decreased ganglio-series gangliosides (GT1b, GD1b, GD1a, GM1) but a statistically significant decrease was detected in frontal cortex, and white matter (nmol LBSA/g fresh weight) or frontal cortex, temporal cortex and basal telencephalon (nmol LBSA/mg DNA). In addition, frontal and parietal cortex also showed elevated concentration (nmol LBSA/g fresh weight) of simple gangliosides (GM2, GM3, GM4, GD3). A decreased concentration of ganglio-series gangliosides in Alzheimer's disease correlates with degeneration of cortical neurons. However, elevation of simple gangliosides in frontal and parietal cortex may correlate with: (a) an accelerated lysosomal degradation of gangliosides occurring during neuronal death (GM2); (b) astrogliosis (GM3 and GD3); and (c) activation of oligodendrocytes (GM4). The fact that gangliosides are altered in Alzheimer's disease might be important for better understanding of the pathogenesis of the disease.

A method for the separation and quantification of a complex ganglioside mixture from a clinically available amount (5 ml) of human cerebrospinal fluid (CSF) is described. After reduction of the CSF volume by ultrafiltration, gangliosides are extracted with methanol/chloroform, then separated and quantified by high performance thin layer chromatography (HPTLC) and direct densitometry. For purification of crude ganglioside extract, the method of choice was microdialysis against water. Recovery for the present method including all methodological steps was 78%. No delective loss of gangliosides was demonstrated. The CSF ganglioside pattern from 'normal' CSF samples resembles that of brain gangliosides, particularly cerebellum gangliosides. Based on chromatographic comparison with standards, the percentages of lipid-bound NeuAc-positive fractions were: GM1 = II3NeuAc-GgOse4Cer (3%), GD3 = II3NeuAc2-Lac-Cer (3%), GD1a = IV3NeuAc,II3NeuAc-GgOse4Cer (15%), X1 (3%), GD1b = II3(NeuAc)2-GgOse4Cer (16%), X2 (3%), GT1b = IV3NeuAc,II3NeuAc2-GgOse4-Cer (41%), and GQ1b = IV3NeuAc2-,II3NeuAc2-GgOse4-Cer (16%). The total ganglioside content varied between 616-944 micrograms/l. Within-run and between-run assay precision (relative standard deviation) for 'normal' pooled CSF ranged from 0.04 to 0.12 for the predominant CSF ganglioside fractions (GD1a, GD1b, GT1b, GQ1b), and from 0.13 to 0.23 for the less pronounced fractions (GM1, GD3).

In this study, tumor and serum gangliosides were analyzed in patients bearing lung planocellular carcinoma (LPC) before and after operative therapy. Tumor tissue, pathohistologically characterized as carcinoma planocellulare corneum (Ca. epidermoide, type 8070/3, WHO, Geneva, 1981), showed an elevated concentration of gangliosides in comparison to normal tung tissue. The composition of gangliosides in LPC tissue varied from one tumor sample to another, however, two general features were observed. First, LPC contained an increased amount of GM3 and a decreased amount of GD3 gangliosides. Second, an elevated proportion of gangliosides migrating as polysialogangliosides (x3, x5, x6) characterized the majority of LPC tissues. On the other hand, serum of patients with LPC contained an elevated amount of gangliosides (15.8 +/- 0.3 mumols/L) in comparison to control serum (6.1 +/- 0.8 mumols/L) (P less than 0.01). However, analyzing the composition of serum gangliosides by thin-layer chromatography, all serum gangliosides were more or less elevated. By day 21 after the surgical removal of LPC, serum gangliosides dropped by approximately 50% approaching the normal values. It seems that elevated serum gangliosides in LPC patients were secreted from carcinoma cells, because they normalized after surgical removal of LPC. Thus, serum gangliosides might be a useful biochemical tool for diagnosis and therapy monitoring of this carcinoma.

The results demonstrated a statistically significant decrease of ganglio-series gangliosides (GTlb, GDlb, GDla, GMl, nmol lipid-bound sialic acid/mg DNA) in frontal and temporal cortex and basal telencephalon of brains with Alzheimer's disease (AD) in comparison to control brains (P less than 0.05). In addition, frontal and parietal cortex also showed somewhat elevated concentrations of simple gangliosides (GM2, GM3, GM4). Changes in gangliosides in seven regions of human brains with AD analyzed, except of the temporal cortex, did not significantly differ in the "a"/"b" ratio (GDla + GMl/GDlb + GTlb) of ganglioside composition in comparison to control brains. In temporal cortex, an decrease of "a"/"b" ratio on the accounts of more decreased GDla and GMl than GDlb and GTlb was found. A decreased concentration of ganglio-series gangliosides in AD probably correlates with degeneration of cortical neurons. However, elevation of simple gangliosides in frontal and parietal cortex might correlate with an accelerated lysosomal degradation of gangliosides and/or astrogliosis occurring during neuronal death.

To test the importance of vitamin D metabolites on intramuscular implants of demineralized bone, four-month-old rats were given either 1a,25-(OH)2D3 or 24R,25-(OH)2D3, or a combination of both metabolites, and sacrificed at intervals ranging from five to 35 days after implantation. Histologically there was a reduced ingrowth of mesenchymal cells into the implanted matrix cylinders in the presence of 1a,25-(OH)2D3; the reduction was followed by decreased total DNA and protein values until the 16th experimental day. At 35 days postimplantation, the quantity of new bone was the same in all treated groups. However, 1a,25-(OH)2D3 increased the alkaline phosphatase activity 60%-110% (depending on the denominator used). The metabolite 24R,25-(OH)2R3 had no effect on cell growth or the alkaline phosphatase activity. These results provide evidence for the inhibitory effect of 1a,25-(OH)2D3 on mesenchymal cell growth and its stimulatory effect on osteoblasts, which are responsible for increased alkaline phosphatase activity and new bone formation in vivo.

The present study describes a short period of cytoarchitectonic development of the anlage of the basal nucleus of Meynert between 9 and 15 weeks of gestation (crown-rump length 42-120 mm). On the basis of temporo-spatial reconstruction of the cytoarchitectonic pattern within the basal telencephalon it was evident that magnocellular aggregations of the basal telencephalon contain the most differentiated cells in the whole prosencephalon of the 15-week-old human fetus. At this stage development many magnocellular islands can be observed in the sublenticular region. However, it seems that they are in antero-posterioral continuation and the real number of magnocellular islands is much smaller than observed in a single section. The most voluminous magnocellular aggregations are situated around the temporal limb of the anterior commissure and below the ventral pallidal surface in the 15th week of gestation. Between 12 and 15 weeks of gestation, at the most rostral levels, the distinct cell group appeared with unique cytoarchitectonic properties ('albino cell group'). This cell group is situated close to the ventral putaminal surface within the capsula externa fibres and it corresponds to the subputaminal nucleus of Ayala.

The administration of aluminium to uraemic rats leads to aluminium accumulation in different brain regions. Aluminium intoxication significantly alters brain gangliosides, the content of which is increased in uraemic animals. This phenomenon can be prevented by administration of 24R,25-dihydroxyvitamin D3 (24,25(OH)2D3). Our results could possibly find an application in the prevention of aluminium-induced encephalopathy in patients on haemodialysis.