Changes In Gangliosides Research Articles

Changes in ganglioside profile in chick embryo retina: Studies on tissue and cell cultures

The developmental profile of gangliosides in the neural retina of the chick embryo is characterized by a progressive decrease in the concentration of GD3 complex from a high level on day 6; by a continuous increase in GD1a concentration; and by less striking increases in GD1b and GT1b concentrations during the growth phase; GM1 increases in the post-mitotic retina. Gangliosides were analyzed by thin layer chromatography and by densitometry of the TLC plates. (Ganglioside nomenclature is according to Svennerholm.37)We have examined comparatively ganglioside changes in organ cultures of retina tissue from 6 day embryos (R36), in cell aggregates and in primary monolayer cultures of R26 cells, all maintained for 6 days in vitro. In all cases, the pattern of ganglioside changes was qualitatively similar to that in the retina in vivo. These results suggest that, unlike some other aspects of retina differentiation, the progression of ganglioside changes in the 6–12 day embryonic retina is not critically dependent on histotypic cell organization or on specific contact-dependent cell interactions; these changes appear to be largely preprogrammed in the cells at some earlier phase of development.

Roles of gangliosides in the surface properties of normal and malignant cells.

Gangliosides are ubiquitous plasma membrane components whose structural characteristics make it possible to establish multiple interactions with the pericellular microenvironment. Several receptorial activities of gangliosides have already been recognized and the possible involvement of gangliosides in growth control, adhesion, differentiation, and immunologic recognition is at present under study. The study of the role of gangliosides in cell growth control has been approached in our laboratory by investigating whether the ganglioside changes found in SV40-transformed Balb/c3T3 cells (SV3T3 cells) revert to a normal pattern in a variant of SV3T3 cells with growth properties similar to those of normal parental cells, the concanavalin A-selected SV3T3 revertant cells. These latter cells showed the same reduction of the more complex gangliosides as found in SV3T3 cells, while their amount of II3NeuAC-LacCer (GM3) was greatly increased compared to that found in either normal or transformed 3T3 cells. In order to study the role of gangliosides in the adhesion process, we analyzed the ganglioside structure of the so-called substrate-attached material, a cell surface structure involved in the adhesion of cells to substrate, from cultures of Balb/c3T3, SV3T3, and concanavalin A-selected SV3T3 revertant cells and from cultures of a system of transformed cells with different metastatic potential: the nonmetastatic B77-3T3 and the highly metastatic AA6 cells. Compared to normal cells, all the transformed cells contained smaller quantities of gangliosides in their substrate-attached material.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in rabbit cerebrum and cerebellum gangliosides during postnatal life. A study especially referring to alkali labile gangliosides

The present study deals with the developmental behaviour of cytosolic and membrane-bound gangliosides, especially the alkali labile species, in rabbit cerebrum and cerebellum from birth to 6 months of life. At all ages the amount of cytosolic gangliosides was less than 0.5% of total gangliosides. The proportion of alkali labile gangliosides on the total membrane-bound ganglioside content and the profile of the individual alkali labile gangliosides during postnatal life were different in cerebellum and cerebrum. In cerebellum the proportion of alkali labile gangliosides progressively increased from 4.6% at birth to 16.7% at 6 months; in cerebrum the proportion decreased from 8.9% at birth to a minimum of 5.5% at 10 days, then slowly increased up to 8.1% at 6 months. All the major alkali labile gangliosides in cerebellum, especially O-Ac-GT1b and O-Ac-GQ1b, tended to accumulate during postnatal life. In cerebrum only two alkali labile gangliosides, namely O-Ac-GT1b and a species not yet identified, increased starting from the 10th day of life, while the other ones progressively diminished after birth.

Developmental changes of ganglioside compositions and biosyntheses in rat bone marrow cells, spleen and thymus.

Studies on developmental changes of ganglioside synthesis and compositions were carried out using rat bone marrow cells, spleen and thymus. Ganglioside synthesis was studied by assaying sialyltransferase for GM3 synthesis and GM1b synthesis. In bone marrow cells, peaks of both enzyme activities occurred coincidentally in 2- to 5-week-old rats. In spleen, the highest activities of these enzymes were observed in one-week-old rats. GM1b synthesis in the thymus was almost constant after birth, but GM3 synthesis could not be detected at any age examined. Developmental changes of gangliosides in these tissues were analyzed by thin layer chromatography. Gangliosides corresponding to GM1b and GM3 were recognized in each tissue. The ganglioside content of the bone marrow cells increased in 2- to 5-week-old rats. Ganglioside corresponding to GM1b was isolated from the bone marrow cells, and its structure was confirmed to be the same as that of GM1b by sequential hydrolysis of the ganglioside with glycosidases. GM3 was a predominant ganglioside in newborn rat spleen. Ganglioside content in the spleen increased during 2-5 weeks after birth and became constant after 9 weeks. In the thymus, more than 10 different gangliosides were discriminated, but significant changes of ganglioside pattern with the progress of development could not be observed. The developmental change of the ganglioside composition coincided well with the change of sialyltransferase activities.

Density-dependent changes in gangliosides and sialidase activity of murine neuroblastoma cells.

Density-dependent changes in ganglioside composition, Vibrio cholerae neuraminidase (VCN)-susceptible sialyl residues, and membrane-associated sialidase activity were determined for the cholinergic murine neuroblastoma cell line S20Y. A decrease in total ganglioside sialic acid and VCN-releasable sialic acid was observed with increasing cell density. GM3 was the major ganglioside component of preconfluent S20Y cells, whereas GD1a was predominant in postconfluent cells. Sialidase activity increased in confluent and postconfluent cells and may account for the reduction in total ganglioside sialic acid observed with increasing cell density. In contrast, while adrenergic N115 cells showed a decrease in VCN-susceptible sialic acid residues with increasing cell density, there was no significant change in ganglioside composition or ganglioside sialic acid levels.

Ganglioside Changes Induced by Tumor Promoters in Promotable JB6 Mouse Epidermal Cells: Antagonism by an Antipromoter

Since cell surface gangliosides have been implicated in the regulation of cell growth and differentiation and since tumor-promoting phorbol esters produce a number of membrane changes, the possibility was investigated that ganglioside changes may play a role in promotion of transformation in JB6 mouse epidermal cells. The studies showed that tumor-promoting but not non-promoting phorbol esters produced decreased precursor incorporation into disialoganglioside GD1b and an unknown ganglioside, Gx. These ganglioside responses to promoters were antagonized by the antipromoter retinoic acid, thus suggesting that alterations in ganglioside levels may be involved in promotion of transformation.

Ganglioside changes in the chicken optic lobes as biochemical indicators of brain development and maturation

The development profiles of 16 different gangliosides of the optic lobes of the chicken were followed from the sixth day of incubation to the tenth posthatching week and correlated to known morphological development. Several, previously undetected novel fractions occurred between the sixth and tenth embryonic days. According to their migration rates on TLC-plates 4 of them may be GT3, GT2, GT1c, GQ1c. Three even more slowly migrating fractions represent penta-, hexa-, and septa-sialogangliosides. At the sixth day of incubation, characterized by maximal proliferation of neuro-epithelial cells, the optic lobes contained predominantly GD3. Up to the eleventh day of incubation, parallel to decreased mitotic activity, maximal cell migration and neuron differentiation, GD3, GD2, and GT3 decreased in favor of newly detected polysialogangliosides. Thereafter, up to hatching, parallel to increased growth and arborization of dendrites and axons as well as synaptogenesis, the newly detected polysialogangliosides decreased in favor of GD1b, GT1b, GQ1b, and GD1a. At hatching the myelin-specific GM4 appeared, reaching about 8% of total ganglioside sialic acid after 10 weeks. Likewise a fraction, migrating somewhat faster than GM1,increased. This band, named GM1', is suggested to be also myelin-associated. The other monosialogangliosides were always minor fractions, none exceeding 4% of total ganglioside sialic acid.

Sialosylgalactosylceramide (GM4) is a major ganglioside in chicken embryonic liver.

The developmental changes in gangliosides of chicken liver were investigated during embryonic and neonatal life. Sialosylgalactosylceramide (GM4) and sialosyllactosylceramide (GM3) were major gangliosides during the entire period investigated. Sialosylgalactosylceramide (GM4) was detected as the predominant species until 2 days before hatching and then GM3 increased to be the major sialoglycolipid. GM4 continued to be detectable until at least 2 weeks after hatching. Monogalactosylceramide was detected as the major neutral glycolipid. The fatty acids obtained from monogalactosylceramide showed a similar pattern to that of GM4.

Effects of Neonatal 6-Hydroxydopamine Treatment on Cortical Development in Mice and Rats as Monitored by Developmental Changes of Gangliosides

In a comparative study newborn rats and mice received subcutaneous (s.c.) injections of 6-hydroxydopamine (6-OHDA: 100 mg/kg) on postnatal days (p.d.) 1-3. In rats the treatment permanently reduced synaptosomal 3H-noradrenaline (3H-NA) uptake in the cortex to about 50-60% of control values. Conversely, cortical 3H-NA uptake was only temporarily reduced in treated mice during the first week and central noradrenergic neurons completely recovered during the second and third week. The different response of mice and rats to 6-OHDA is suggested to be due to earlier maturation of the noradrenergic system in mice, making it less vulnerable to neonatal injections of the neurotoxin. To determine whether the development of the cortex would be altered after degeneration of its noradrenergic innervation, developmental changes of cortical ganglioside content and composition of 6-OHDA-treated animals were compared to that of littermate controls. In 18-day-old rats, where reduction of 3H-NA uptake had persisted, ganglioside content was reduced by 16.5%, indicating growth impairment of neuronal membrane structures. Cortical gangliosides of younger rats and all the stages studied in mice were not affected by 6-OHDA treatment.

Ganglioside changes during cell aging in human diploid fibroblast tig-1

Gangliosides of human diploid fibroblast, TIG-1, derived from fetal lung were analyzed during cell aging. The major gangliosides of TIG-1 cells were G M3 and G D3. During cell aging, G M3 and other gangliosides were decreased or below detection level. Lipid-bound sialic acid per mg protein was 2μg at the early, middle and late passages, but between the middle and late passage it was twofold higher than the other passages.

Developmental profiles of gangliosides in mouse and rat cerebral cortex.

Developmental profiles of 11 gangliosides, concentration of lipid- and glycoprotein-bound sialic acid, and activity of AChE of the rat and mouse cerebral cortex were followed from the 7th day of gestation to the 21st postnatal day.There are three main changes in ganglioside concentration, which are similar in both species. The first occurs from gestation day 10 until birth: parallel to decreased proliferation, cell migration, and neuroblast differentiation, GM3 and GD3 in mouse cortex and GD3 in the rat's decreases in favor of GQ1b, GT1b, and GD1a.The second occurs from birth until the first postnatal week: Parallel to increased growth and arborization of dendrites and axons as well as synaptogenesis in rats and mice, there is a two-fold rise of GD1a, whereas GQ1b and GT1b remain on a nearly constant level. Concomitantly, GM3 and GD3 decreases. The third period of ganglioside changes starts in the second postnatal week, parallel to onset of myelination, and is characterized by an increase of GM1 in parallel with a decrease of the polysialogangliosides GT1b and GQ1b.

Responses of preneoplastic epidermal cells to tumor promoters and growth factors: use of promoter-resistant variants for mechanism studies.

The JB6 mouse epidermal cell model system is being used to study the mechanism of promotion of transformation. Promotion of anchorage independence in JB6 cells occurs in response to second-stage but not first-stage promoters, and is inhibited by inhibitors of second-stage not first-stage promotion. A number of variants that are resistant to the phorbol diester TPA have been derived. Some are resistant to plateau density mitogenic stimulation by TPA; others are resistant to promotion of anchorage independence by TPA. Some of the mitogen-resistant variants were promotable by TPA, thus ruling out a requirement for TPA mitogenesis in promotion of transformation in JB6 cells. TPA promotable clones were also sensitive to mezerein and EGF while the TPA nonpromotable variants were also resistant to mezerein and EGF, suggesting that sensitivity to promoters in these JB6 cells is determined at a level distal to receptor binding. Promotion sensitivity did not require available EGF receptors since two TPA promotable variants were EGF receptorless. The mitogenic response of JB6 cells to TPA may however be mediated by EGF since four of four mitogen-resistant variants showed low to zero levels of EGF binding. Tumor promoting phorbol esters produce specific changes in cellular gangliosides. Certain of these changes occur in promotable but not nonpromotable variants of JB6 cells, suggesting that ganglioside changes may be involved in the process of promotion of transformation.

Cell biological and immunological significance of ganglioside changes associated with transformation.

Glycolipid changes associated with oncogenic transformation have been extensively studied by a number of investigators on chemical and enzymatic basis. An incomplete synthesis of complex glycolipids and an associated accumulation of its precursor glycolipids are the common change observable in many transformed cells irrespective of the transforming agents (see for reviews, Hakomori 1973; 1975; Brady and Fishman 1974; Richardson et al 1976). However, the other type of glycolipid change, i.e. a synthesis of a new glycolipid absent in normal tissue, or foreign to the host may occur in some experimental tumour and in human tumour; a novel fucolipid in rat hepatoma (Baumann et al 1978), A-like antigen in tumours of blood group 0 or B individuals (Hakomori et al 1967; Hakkinen 1970), blood group P1 and P antigen in a tumour of the rare pp individual (Levine et al 1951), and Forssman antigen in tumours of F− individuals (Hakomori et al 1977) are typical examples. These components are normally absent in progenitor cells or in host’s tissues and therefore could be a tumour-associated antigen. All of these antigens are glycosphingolipid and may be synthesized through an activation of a new glycosyltransferase which is foreign to the host (see for reviews Hakomori and Young 1978; Young and Hakomori 1978).

Ganglioside changes in the chicken optic lobes and cerebrum during embryonic development

The developmental profiles of 15 different gangliosides of the optic lobes and cerebrum of the chicken were followed from the 6 th day of incubation to hatching and correlated to morphological development. Five of these gangliosides appearing in both structures between the sixth and tenth day, have not been reported previously in higher vertebrates. Three chromatographed on TLC-plates similarly to GT3, GT2, and GT1c gangliosides, which have been demonstrated in fish brain. One fraction moved just below GQ1b and is suggested, to contain GQ1c. These "novel" gangliosides, which are possibly related to a recently proposed separate and probably phylogenetically older biosynthetic pathway, contained up to 20% of total ganglioside sialic acid. The fifth "novel" fraction, containing up to 16% of total ganglioside-sialic acid, moved below the penta-sialoganglioside GP1 and is suggested to contain hexa-sialogangliosides.There were two main changes in ganglioside synthesis, which were identical in both structures.The first occurred from the sixth to the eleventh day, parallel to decreased proliferation, maximal cell migration and neuroblast differentiation, GD3 and GD2 decreased rapidly in favour of GQ1b, GP1, and to the "novel" fractions, described above.The second occurred from the eleventh to the eighteenth day, parallel to increased growth and arborization of dendrites and axons as well as functional establishment of synaptic contacts, there was a sharp rise in the amount of GD1b, GT1b, and GD1a. Concomitantly the "novel" gangliosides decreased. At hatching GD1a was the predominant ganglioside. GM3, GM2, and GM1 were always minor fractions, each accounting for less than 4% of total ganglioside-sialic acid. GM4 was never detected, indicating neglegible myelinisation until hatching.

Changes of brain gangliosides in chicken and mice during heterothermic development

Developmental profiles of brain gangliosides of chicken and mice were correlated to thermo-biological parameters. In parallel with an increasing body temperature and resistance to cold stress (within the first 11 postnatal days) the brain gangliosides change to a less polar pattern, indicated by a higher proportion of oligosialogangliosides.

Brain gangliosides and temperature adaptation in eury- and stenothermic teleost fish (carp and rainbow trout)

1. 1.|The brain ganglioside pattern of eurythermic carp ( Cyprinus carpio) and stenothermic rainbow trout ( Salmo gairdneri) was investigated by means of biochemical methods under experimentally induced temperature changes (acclimination), and seasonal temperature fluctuations (acclimatization). 2. 2.|In both species during the process of thermal adaptation to lowered environmental temperatures, changes in the brain gangliosides could be registered resulting in a more polar pattern. 3. 3.|While in carp this “polysialization” was indicated by a decrease of all oligosialogangliosides in favour of more polar fractions; in rainbow trout a more differentiated change of the pattern occurred characterized by a significant decrease (∼ 60%) in the concentration of the monosialoganglioside GM 3. 4. 4.|The results are discussed with respect to a possible involvement of neuronal gangliosides in the mechanism of thermal adaptation of poikilothermic animals to changes in the environmental temperatures.

Changes in rat brain gangliosides following active avoidance conditioning

Brain gangliosides of rats trained in a conditioned avoidance Sidman task and undisturbed rats in their cages were studied. The ( 14C) acetate was injected intracerebrally seven days before the starting of 30 days training. Thirty-seven days after injection all rats were killed and ganglioside fractions were isolated from neocortex, hippocampus, brain stem, cerebellum and residual cerebral tissue of each one brain. Trained rats had higher levels of ( 14 C)-labeled polysialogangliosides (G 1, G 2, G 3) in hippocampus and neocortex than the controls. Regarding the rest of the brain areas, a significant increase of G 2 in the residual cerabral tissue of the trained as compared with the controls was found. The results suggest that the sialic acid rich gangliosides of only certain parts of the brain are affected by the Sidman avoidance conditioning of the animals.

Developmental changes in gangliosides during myogenesis of a rat myoblast cell line and its drug resistant variants

Cloned cells of a myoblast line show the presence of GM 3, GM 2, GM 1 and GD 1a gangliosides. The amount of GM 3, GM 2 and GM 1 gangliosides does not vary significantly during the differentiation of myoblasts to myotubes. However, the concentration of GD 1a transiently increases almost 3-fold just prior to the fusion of myoblasts and returns to the basal levels in the myotubes. Mutant myoblasts selected for 5-azacytidine resistance and unable to fuse produce only GM 3 and traces of GM 2. We conclude that GD 1a probably participates in the fusion process through yet unknown mechanism.

Developmental patterns of gangliosides and of phospholipids in chick retina and brain.

Abstract— The changes in phospholipids and gangliosides during ontogenesis of chick retina have been compared with those in brain. Three phases of accumulation of ganglioside NeuNAc in the retina were detected. In contrast, brain NeuNAc rapidly increased during embryonic life until hatching, followed by a slower increase up to the adult stage. The phospholipid changes in retina and in brain occur in a‐similar manner to the variations observed for gangliosides, however in retina the changes of phospholipid content are less marked than in brain, during embryonic life. There were marked changes in the retina and brain ganglioside patterns with age. Gd3 and Gd1b decreased rapidly in per cent; correspondingly, Gd1a increased during embryonic life and became the major ganglioside in place of Gd3. There was a similarity between ganglioside patterns of chick retina and brain. Except for some slight variations during embryonic life, the retinal phospholipid pattern did not change noticeably.

Cell contact-dependent ganglioside changes in mouse 3T3 gibroblasts and a suppressed sialidase activity on cell contact.

Certain enzyme activities for synthesis and degradation of gangliosides and the chemical quantity and incorporation of radioactivity from [14C] galactose into gangliosides have been studied in 3T3 cells and their transformed counterparts at various cell population densities. The chemical quantity of and the incorporation of radioactivity into GD1a ganglioside increased at the early stage of cell contact ("contact response" of ganglisoide), whereas response was not detectable in transformed 3T3 cells at any stage of cell contact. These phenomena were reproduced in five separate qualitative analyses and two quantitative determinations of gangliosides. As the basis of these phenomena, a membrane-bound sialidase activity which acted on gangliosides was suppressed in 3T3 cells at the "touching" stage of cell-to-cell contact. Transformed cells did not display the change of sialidase activity at any stage of cell contact.