Ganglioside structures and distribution: are they localized at the nerve ending?

Ganglioside patterns in human spinal cord

OBJECTIVE

To examine the distribution of gangliosides in human cervical and lumbar spinal cord.

SETTING

Magdeburg, Germany.

METHODS

The ganglioside distribution of human cervical and lumbar spinal cord enlargements from 10 neurological normal patients was analyzed. Gangliosides were isolated from different areas corresponding to the columna anterior, columna lateralis and columna posterior.

RESULTS

Ganglioside GfD1b/GD1b and GD3 were the most abundant gangliosides in all examined tissues. The total concentration of sialic acid bound gangliosides GM2 and GM3 was less than 5%. The GD3 fraction constantly consisted of a double band as assessed by TLC after lipid extraction. There were significant differences in the ganglioside distribution when comparing tissue from the columna anterior, columna lateralis and columna posterior of the lumbar enlargement of the spinal cord.

CONCLUSION

Differences in the ganglioside composition in human spinal cord regions may reflect the different function of those molecules in the two regions investigated.

Selective cell-cycle arrest and induction of apoptosis in proliferating neural cells by ganglioside GM3

Control of cell proliferation and cell survival is critical during development of the vertebrate central nervous system (CNS). Much of the cell death seen during early stages of CNS development occurs through apoptosis; however, the factors that induce this early apoptosis are not clearly understood. Gangliosides, sialylated glycosphingolipids, are expressed in the CNS and have been proposed to regulate cell growth and differentiation. Here we show that the simple ganglioside GM3 selectively inhibits the proliferation of and induces apoptosis of actively dividing astrocyte precursors and other neural progenitors. The inhibition of astrocyte precursor proliferation by GM3 appears to be mediated in part by the cyclin-dependent kinase (Cdk) inhibitor p27(Kip1). During neonatal development there is extensive cell proliferation and little apoptosis in the ventricular and subventricular zones of the CNS. This proliferation was dramatically inhibited and the degree of apoptosis dramatically increased following intraventricular administration of GM3. These data suggest that GM3, a simple ganglioside, may regulate cell proliferation and death in the CNS and as such may have potential for brain tumor therapy.

GM3 as a novel growth regulator for human gliomas

The simple ganglioside GM3 inhibits proliferation and induces apoptosis in proliferating immature rodent CNS cells. To determine whether GM3 influenced the expansion of human neural tumors the effects of GM3 treatment on primary human brain tumors were assayed. Here we demonstrate that GM3 treatment dramatically reduces cell numbers in primary cultures of high-grade human glioblastoma multiforme (GBM) tumors and the rat 9L cell gliosarcoma cell line. By contrast, GM3 treatment had little effect on cell number in cultures of normal human brain. A single injection of GM3 3 days after intracranial implantation of 9L tumor cells in a murine xenograft model system resulted in a significant increase in the symptom-free survival period of host animals. The effects of GM3 were not restricted to GBMs and 9L cells. Cultures of high-grade ependymomas, mixed gliomas, astrocytomas, oligodendrogliomas, and gangliogliomas were all susceptible to GM3 treatment. These results suggest that GM3 may have considerable value as a selectively toxic chemotherapeutic agent for human high-grade gliomas.

Anti-GQ1b antibodies and evoked acetylcholine release at mouse motor endplates

Miller Fisher syndrome (MFS) is clinically characterized by ataxia, areflexia, and ophthalmoplegia, and is associated with serum anti-GQ1b-ganglioside antibodies. We have previously shown that anti-GQ1b antibodies induce complement-dependent, alpha-latrotoxin-like effects at mouse neuromuscular junctions (NMJs) in vitro. This effect comprises a massive increase in spontaneous quantal acetylcholine (ACh) release, accompanied by block of evoked release and muscle paralysis. This mechanism may contribute to the motor features of MFS. Whether the block of evoked ACh release is a primary effect of anti-GQ1b antibodies or occurs secondary to massive complement-dependent spontaneous release is unknown. Using conventional micro-electrode methods, we measured in detail ACh release evoked with low- and high-rate nerve stimulation, and studied the effect on it of a purified MFS IgG and a mouse monoclonal anti-GQ1b IgM (without added complement). We found that evoked transmitter release was unaffected. Control experiments proved binding of anti-GQ1b antibody at the NMJ. We conclude that the block of nerve-evoked ACh release at the NMJ is not a primary effect of anti-GQ1b antibodies, but is dependent on antibody-mediated complement activation. It remains to be determined whether the block of nerve-evoked ACh release is the consequence of massive spontaneous ACh release or occurs as a concomitant event.

D-Serine inhibits serine palmitoyltransferase, the enzyme catalyzing the initial step of sphingolipid biosynthesis

Serine palmitoyltransferase (SPT), responsible for the initial step of sphingolipid biosynthesis, catalyzes condensation of palmitoyl coenzyme A and L-serine to produce 3-ketodihydrosphingosine (KDS). For determination of the stereochemical specificity of the amino acid substrate, a competition analysis of the production of [(3)H]KDS from L-[(3)H]serine was performed using purified SPT. D-Serine inhibited [(3)H]KDS production as effectively as non-radioactive L-serine, whereas neither D-alanine nor D-threonine showed any significant effect. Incubation of purified SPT with [palmitoyl 1-(14)C]palmitoyl coenzyme A and D-serine did not produce [(14)C]KDS, while the control incubation with L-serine did. These results suggest that D-serine competes with L-serine for the amino acid recognition site of SPT, but that D-serine is not utilized by this enzyme to produce KDS.

Effects of GM1 ganglioside treatment on pre- and postsynaptic dopaminergic markers in the striatum of parkinsonian monkeys

GM1 ganglioside administration has previously been shown to increase striatal dopamine levels and to enhance the density of tyrosine hydroxylase-positive fibers in the striatum of monkeys made parkinsonian by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The present study examined the extent to which GM1 administration promotes recovery of dopamine terminals and reverses lesion-induced changes in postsynaptic receptors in the striatum of MPTP-treated monkeys. All MPTP-treated animals developed severe parkinsonism. GM1-treated monkeys exhibited significant functional recovery after 6 weeks of treatment, whereas saline-treated controls remained parkinsonian over the same time period. MPTP exposure resulted in profound decreases in [(3)H]-mazindol binding to dopamine transporters in the caudate and putamen and increased D1 and D2 receptor binding in several striatal regions. GM1 treatment resulted in significant increases in striatal [(3)H]-mazindol binding and decreases in D1 binding compared to control animals in many striatal regions. GM1 treatment did not significantly affect D2 binding. These results show that GM1 treatment can partially restore striatal dopaminergic terminals and partially reverse postsynaptic changes in dopamine receptors in a nonhuman primate model of parkinsonism.

Gangliosides asymmetrically alter the membrane order in cultured PC-12 cells

Exogenous gangliosides readily associate with the cell membranes and produce marked effects on cell growth and differentiation. We have studied the effect of bovine brain gangliosides (BBG) on the membrane dynamics of intact cells. The structural and dynamic changes in the cell membrane were monitored by the fluorescence probes DPH, TMA-DPH and laurdan. Incorporation of BBG into the cell membrane decreased the fluorescence intensity, lifetime and the steady state anisotropy of TMA-DPH. Analysis of the time resolved anisotropy decay by wobbling in the cone model revealed that BBG decreased the order parameter, and increased the cone angle without altering the rotational relaxation rate. The fluorescence intensity and lifetime of DPH were unaffected by BBG incorporation, however, a modest increase was observed in the steady state anisotropy. BBG incorporation reduced the total fluorescence intensity of laurdan with pronounced quenching of the 440-nm band. The wavelength sensitivity of generalized polarization of laurdan manifested an ordered liquid crystalline environment of the probe in the cell membrane. BBG incorporation reduced the GP values and augmented the liquid crystalline behavior of the cell membrane. BBG incorporation also influenced the permeability of cell membranes to cations. An influx of Na+ and Ca2+ and an efflux of K+ was observed. The data demonstrate that incorporation of gangliosides into the cell membrane substantially enhances the disorder and hydration of the lipid bilayer region near the exoplasmic surface. The inner core region near the center of the bilayer becomes slightly more ordered and remains highly hydrophobic. Such changes in the structure and dynamics of the membrane could play an important role in modulation of transmembrane signaling events by the gangliosides.

Ganglioside GM1 potentiates NGF action on axotomised medial septal cholinergic neurons

Transection of the fimbria fornix leads to retrograde degeneration of axotomised septal cholinergic neurons as manifested by loss of choline acetyltransferase and p75NGFR immunoreactivity. Intracerebroventricularly administered nerve growth factor initiated at the time of axotomy can prevent these changes. We have shown that concurrent intraperitoneal administration of GM1 with a low and otherwise unprotective intracerebroventricular dose of nerve growth factor, can also prevent the loss of these fimbria fornix axotomised cholinergic neurons, where GM1 alone does not have this effect. This study further confirms the neuroprotective actions of GM1 and suggests that it may interact to potentiate the effect of nerve growth factor on these axotomised septal cholinergic neurons.

Membrane carbohydrate conjugates desialylation does not alter [3H]-dopamine uptake in rat striatal slices

Incubation of rat striatal slices induced a large decrease (about 50%) of DA uptake and a slight desialylation of polysialogangliosides (GT1b, GD1b, GD1a) with an increase of monosialogangliosides (GM1). Moreover, a pretreatment of slices by exogenous added neuraminidase of Vibrio cholerae did not modify DA uptake, although the pattern of gangliosides was modified and there was considerable loss (about 45%) of sialic acid in gangliosides and glycoproteins. It was verified that neuraminidase activity occured in synaptic membrane. Thus, DA uptake was apparently not altered by desialylation of plasma membrane carbohydrate conjugates.

Spinal cord injury in the rat

Only limited therapeutic measures are currently available for the treatment of spinal cord injury. This review describes the pathologic mechanisms of trauma-induced spinal cord injury in rats, which will contribute to new understanding of the pathologic process leading to spinal cord injury and to further development of new therapeutic strategies. Spinal cord injury induced by trauma is a consequence of an initial physical insult and a subsequent progressive injury process that involves various pathochemical events leading to tissue destruction; the latter process should therefore be a target of pharmacological treatment. Recently, activated neutrophils have been shown to be implicated in the latter process of the spinal cord injury in rats. Activated neutrophils damage the endothelial cells by releasing inflammatory mediators such as neutrophil elastase and oxygen free radicals. Adhesion of activated neutrophils to the endothelial cell could also play a role in endothelial cell injury. This endothelial cell injury could in turn induce microcirculatory disturbances leading to spinal cord ischemia. We have found that some therapeutic agents that inhibit neutrophil activation alleviate the motor disturbances observed in the rat model of spinal cord injury. Methylprednisolone (MPS) and GM1 ganglioside, which are the only two pharmacological agents currently clinically available for treatment of acute spinal cord injury, do not inhibit neutrophil activation in this rat model. Taken together, these observations raise a possibility that other pharmacological agents that inhibit neutrophil activation used in conjunction with MPS or GM1 ganglioside may have a synergistic effect in the treatment of traumatic spinal cord injury in humans.

Clinical trials of pharmacotherapy for spinal cord injury

Spinal cord injury remains with limited natural recovery and only a few general ineffective treatment options. Recent publications have reported enhanced neurologic recovery with the use of methylprednisolone and GM-1 ganglioside. The results of the Maryland GM-1 Ganglioside Study reported a significant drug effect with respect to the fraction of patients that had a change of two or more Frankel grades from entrance into the study to 1-year follow-up. This study formed the basis for the currently ongoing larger placebo-controlled multicentered study using Sygen GM-1 following acute spinal cord injury. This study has entered 797 patients and is expected to present results in early 1998.

Significance of gangliosides in neuronal differentiation of neuroblastoma cells and neurite growth in tissue culture

Addition of DL-threo-1-phenyl-2-decanolylamine-3-morpholino-1-propanol HCl (PDMP; 7-24 microM) or Fumonisin B1 (FB1; 30-50 microM) to SH-SY5Ytrk-A human neuroblastoma cells results within 4 days in a 40% decrease of the ganglioside content and in a reduction of nerve-growth-factor (NGF)-induced outgrowth of neuritic processes. NGF-induced enhancement of GAP-43 expression was not affected. However, unlike controls, immunostained GAP-43 appeared concentrated in defined areas of cell perikarya and mostly absent from cell processes. Presence of 20-microM exogenous GM1 for 4 days in NGF and PDMP containing cell cultures led to an increase of cell-associated GM1(15-fold), GM2 (10-fold), GM3 (15 fold), GD1a (4-fold), GD2, GD1b, and GT1b (all 3-fold), and partially reversed the PDMP (and FB1) effects on neurite growth and GAP-43 distribution. In a newly developed neuronal tissue culture system, PDMP and FB1 led to a comparable dose-dependent inhibition of neurite outgrowth from embryonic chicken spinal cord explants, which had been embedded into a fibrin matrix. In this system, addition of GM1 led to a further inhibition of neurite growth, probably due to an interaction with growth-promoting components present in the surrounding fibrin matrix.

The role of globo-series glycolipids in neuronal cell differentiation--a review

Alterations in glycolipid composition as well as glycosyltransferase activities during cellular differentiation and growth have been well documented. However, the underlying mechanisms for the regulation of glycolipid expression remain obscure. One of the major obstacles has been the lack of a well defined model system for studying these phenomena. We have chosen PC12 pheochromocytoma cells as a model because (a) the properties of these cells have been well characterized, and (b) they respond to nerve growth factor (NGF) by differentiating into sympathetic-like neurons and are amenable to well-controlled experimentation. Thus, PC12 cells represent a suitable model for studying changes in glycolipid metabolism in relation to cellular differentiation. We have previously shown that subcloned PC12 cells accumulate a unique series of globo-series neutral glycolipids which are not expressed in parental PC12 cells. This unusual change in glycolipid distribution is accompanied by changes in the activities of specific glycosyltransferases involved in their synthesis and is correlated with neuritogenesis and/or cellular differentiation in this cell line. We have further demonstrated that changes in the glycosyltransferase activities may be modulated by the phosphorylation states of the cells via protein kinase systems. We conclude that these unique globo-series glycolipids may play a functional role in the initiation and/or maintenance of neurite outgrowth in PC12 cells.

Opioid receptor and calcium channel regulation of adenylyl cyclase, modulated by GM1, in NG108-15 cells: competitive interactions

GM1 ganglioside was previously shown to function as a specific regulator of excitatory opioid activity in dorsal root ganglion neurons and F11 hybrid cells, as seen in its facilitation of opioid-induced activation of adenylyl cyclase and its ability to dramatically reduce the threshold opioid concentration required to prolong the action potential duration. The elevated levels of GM1 resulting from chronic opioid exposure of F11 cells were postulated to cause the ensuing opioid excitatory supersensitivity. We now show that GM1 promotes opioid (DADLE)-induced activation of adenylyl cyclase in NG108-15 cells which possess the delta-type of receptor. In keeping with previous studies of other systems, this can be envisioned as conformational interaction of GM1 with the receptor that results in uncoupling of the receptor from Gi and facilitated coupling to Gs. This would also account for the observation that DADLE-induced attenuation of forskolin-stimulated adenylyl cyclase was reversed by GM1, provided the cells were not pretreated with pertussis toxin. When the cells were so pretreated, GM1 evoked an unexpected attenuation of forskolin-stimulated adenylyl cyclase attributed to GM1-promoted influx of calcium which was postulated to inhibit a calcium-sensitive form of adenylyl cyclase. This is concordant with several studies showing GM1 to be a potent modulator of calcium flux. Pertussis toxin in these experiments exerted dual effects, one being to promote interaction of the delta-opioid receptor with Gs through inactivation of Gi, and the other to enhance the GM1-promoted influx of calcium by inactivation of Go; the latter is postulated to function as constitutive inhibitor of the relevant calcium channel. NG108-15 cells thus provide an interesting example of competitive interaction between two GM1-regulated systems involving enhancement of both opioid receptor excitatory activity and calcium influx.

The role of GM1-ganglioside in the injured spinal cord of rats: an immunohistochemical study using GM1-antisera

The effect of GM1-ganglioside (GM1) administration was investigated in the injured spinal cord of rats. Immunohistochemistry using GM1-antisera was applied in the study of GM1 distribution, and locomotor recovery was also evaluated. A total of 86 rats, subdivided into four groups, were used in the study. The SI + GM1 group (n = 30) underwent a thoracic cord injury, and then received daily intraperitoneal injections of GM1 (10 mg/kg) from 0 to 13 days after injury. The SI group (n = 30) also underwent thoracic cord injury, but did not receive GM1 treatment. The GM1 group (n = 20) received daily injections of GM1 in the absence of any spinal cord injury. The control group (n = 6) neither underwent spinal cord injury nor received GM1 treatment. The animals were sacrificed at 1, 3, 5, 7, and 14 days after injury for immunohistochemical evaluation. GM1 immunoreactive axons, myelin sheaths, and glial cells were counted in 5 light microscopic fields of spinal white matter. Immunohistochemical studies of the spinal cord revealed that GM1 treatment significantly increased both GM1-positive axons and GM1-positive myelin sheaths in the lateral funiculus surrounding the lesion site. The exogenous GM1 was incorporated predominantly into the myelin sheath rather than the axon. This distribution was detectable by day 1 of injury and persisted until day 14, and was significantly different from that of the control group on days 1 and 7. Moreover, GM1 treatment significantly accelerated the recovery of motor function. Collectively, these results suggest that exogenous GM1 administration after a spinal cord injury results in the rapid transfer of GM1 to the lateral funiculus where the motor transmission pathway is located. Furthermore, exogenous GM1 was shown to be specifically incorporated into the myelin sheath. Thus GM1 treatment may prevent demyelination and may contribute to motor function recovery.

Parkinson's disease, trophic factors, and adrenal medullary chromaffin cell grafting: basic and clinical studies

Neural transplantation is one of the promising approaches for the treatment of Parkinson's disease. Although the strategy of using adrenal medulla as donor tissue, rather than fetal nigra tissue, started as an alternative method, recent experimental studies demonstrated the efficacy of adrenal medulla grafting as a neurotrophic source. Many methods to increase the survival of grafted chromaffin cells have been developed, some of which have already been applied clinically with encouraging results. This review summarizes the advancements of adrenal medulla grafting in basic and clinical studies. Special attention is focused on the relationship with neurotrophic factors and how we can enhance the survival of grafted chromaffin cells.

Locating lipids in the CNS: an historical perspective

Localization of lipids in the CNS is considered from an historical perspective. General consideration is given to the identification and separation of different parts of the CNS and to the recognition and detection of lipids. Problems associated with each of these aspects are noted. More treatment is given to the localization of gangliosides and the contributions of Leon Wolfe are highlighted.

Monosialoganglioside cotreatment prevents haloperidol treatment-associated loss of cholinergic enzymes in rat brain

Effects of monosialoganglioside (GM1 ganglioside) cotreatment with haloperidol (HAL) were studied in rat on the haloperidol treatment-associated changes in cholinergic enzymes, choline acetyltransferase (ChAT), and acetylcholinesterase (AChE) in three brain regions of interest: striatum, hippocampus, and cerebral cortex. Short-term (8 days) haloperidol treatment significantly increased the levels of both ChAT and AChE in all the three regions of brain, as compared with controls (for ChAT: p < .0001 for all comparisons, and for AChE: striatum: p < .0001; hippocampus: p < .0003; cortex: p < .05). Cotreatment with GM1 ganglioside further increased the ChAT activity relative to haloperidol treatment alone in all three regions (p < .05). The AChE activity was also significantly higher than controls in all three regions (p < .05 for all comparisons) and higher than haloperidol treatment only in hippocampus (p < .02). After chronic haloperidol treatment (45 days), ChAT activity in cortex had returned to control values in both HAL and HAL + GM1 groups, with no significant group differences remaining (p = .10). By contrast, relative to control values, HAL and HAL + GM1 groups both showed lower ChAT activity in the striatum, as well as in the hippocampus (p < .0001 for both), with significantly lower ChAT activity in the HAL than in the HAL + GM1 group for both areas (p = < .0001 for both). AChE activity showed a significant difference only between the HAL and HAL + GM1 groups in the cortex (p = .003), but no significant effects of group were seen on AChE activity in either striatum or hippocampus. These data suggest that the protective effects of GM1 ganglioside cotreatment on haloperidol-induced alterations in cholinergic systems can be relevant for protecting against the complications of neuroleptic-induced parkinsonism.

Auditory brainstem responses of CBA/J mice with neonatal conductive hearing losses and treatment with GM1 ganglioside

Exogenous administration of GM1 ganglioside to CBA/J mice with a neonatal conductive hearing loss ameliorates the atrophy of spiral ganglion neurons, ventral cochlear nucleus neurons, and ventral cochlear nucleus volume. The present investigation demonstrates the extent of a conductive loss caused by atresia and tests the hypothesis that GM1 ganglioside treatment will ameliorate the conductive hearing loss. Auditory brainstem responses were recorded from four groups of seven mice each: two groups received daily subcutaneous injections of saline (one group had normal hearing; the other had a conductive hearing loss); the other two groups received daily subcutaneous injections of GM1 ganglioside (one group had normal hearing; the other had a conductive hearing loss). In mice with a conductive loss, decreases in hearing sensitivity were greatest at high frequencies. The decreases were determined by comparing mean ABR thresholds of the conductive loss mice with those of normal hearing mice. The conductive hearing loss induced in the mice in this study was similar to that seen in humans with congenital aural atresias. GM1 ganglioside treatment had no significant effect on ABR wave I thresholds or latencies in either group.

Region distribution of the gangliosides in rat brain after chronic ethanol treatment

In this study the effects of chronic ethanol administration on the regional distribution of brain gangliosides were investigated. A total of 36 60-d-old male Wistar rats weighing approximately 200 g was divided into two groups of 18 animals each. The ethanol-consuming group was offered drinking fluid (25% sucrose-32% ethyl alcohol, w/w) ad libitum, and the control group was given a sucrose solution isocaloric with the ethanol-sucrose solution. After 6 mo of chronic ethanol treatment, cerebral cortex, N. caudatus, hypothalamus, thalamus, and hippocampus were analyzed with respect to their ganglioside pattern (GM2, GM1, GD1a, GD1b, GT1b, and GQ). The results showed that there were highly significant effects of ethanol on hypothalamus GD1b and GT1b, thalamus GM1 and GD1a, and hippocampus GM1, GD1b, and GT1b ganglioside distribution. It was found that ethanol differently affected the gangliosides in these brain regions.

Glycolipidic component of the epithelial cell coat of the endolymphatic sac

The endolymphatic sac (ES) is thought to synthesize and secrete glycoconjugates such as sulfated glycoproteins into the endolymphatic lumen. Ganglioside Gm1 is a specialized glycolipid containing one sialic acid molecule, which is generally found in the outer leaflet of the cell membrane. This glycolipid, which is known to be a specific receptor for cholera toxin (CT), acts as a membrane transducer and is involved in the modulation of cell metabolism, growth and regeneration. In the present study we identified Gm1 by studying the distribution of the FITC-labeled CT-subunit B in the ES epithelium of adult guinea pigs. Our findings indicate the presence of this ganglioside in the ES, with a predominant localization in the basolateral aspect of the epithelial cell layer. No detectable differences between ES cell types could be identified, whilst the ES distal and intermediate portions showed more reactivity than the proximal portion. This study, which represents the first description of a lipidic glycoconjugate component in the ES, provides evidence in support of the role of the ES in the turnover and regulation of inner ear fluids.

Efficacy of pretransection of peripheral nerve for promoting the survival of cografted chromaffin cells and recovery of host dopaminergic fibers in animal models of Parkinson's disease

Nerve growth factor (NGF) concentration in the distal stump of the transected peripheral nerve has been shown to increase more than 20 times one day after transection. We performed adrenal medullary alone grafts or cografts of adrenal medulla and acutely transected or pretransected (24 h before) sciatic nerve into the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice, and compared the survival of chromaffin cells and the recovery of the host-intrinsic dopaminergic fibers using tyrosine hydroxylase immunocytochemistry and high-performance liquid chromatography. We also performed peripheral nerve alone grafting (acutely transected or pretransected) for comparison. Adrenal medullary chromaffin cells cografted with pretransected sciatic nerve survived better than those in adrenal grafts alone or those cografted with acutely transected sciatic nerve. Host dopaminergic fiber recovery was also most prominent in mice cografted with pretransected peripheral nerve. Animals receiving grafts of peripheral nerve alone showed limited recovery of host dopaminergic fibers and the degree of recovery was lower than that of animals receiving cografts of adrenal medulla with pretransected peripheral nerve. We conclude that pretransected peripheral nerve enhanced the survival of cografted chromaffin cells and this increased survival led to promote the recovery of host-intrinsic dopaminergic fibers. This grafting procedure might be promising in application to patients with Parkinson's disease.

Exogenous GM1 ganglioside effects on conductive and sensorineural hearing losses

Both CBA/J mice with neonatal cochlea removals and CBA/J mice with neonatal atresias of the external auditory meatus have significantly smaller ventral cochlear nucleus is greater in the mice with cochlea removals, but the soma area reduction is greater in the mice with external auditory meatus atresias. GM1 gangliosides were subcutaneously injected daily into a group of CBA/J mice with conductive hearing loss caused by neonatal removals of their left external auditory meatus, and into a group of CBA/J mice unilaterally deafened by left cochlea removals. In the mice with conductive hearing loss, the ganglioside treatment significantly ameliorated the atrophy of spiral ganglion neurons, ventral cochlear nucleus neurons, and ventral cochlear nucleus volume. In unilaterally deafened mice, the ganglioside treatment had no measurable effect on the atrophy of ventral cochlear nucleus neurons or of ventral cochlear volume. It is suggested that GM1 ganglioside treatment potentiates growth factors which sustain spiral ganglion integrity and that this sustained activity of the spiral ganglion in turn maintains the integrity of the cochlear nuclei.

Gangliosides. Their role in clinical neurology

Gangliosides are normal constituent of mammalian vertebrate cell membranes and are particularly abundant in the central and peripheral nervous systems. The biological effects of exogenously administered gangliosides have been extensively investigated in vitro and in experimental animal models where they have neuronotrophic and neuritogenic properties. Despite these findings there is still little evidence that treatment with parenteral gangliosides in humans can be effective in peripheral neuropathies or other neuromuscular diseases. The initial preliminary reports on the positive effects of GM1 in cerebrovascular diseases and spinal cord injury need to be confirmed in larger controlled trials. At the same time the occasional development of an acute motor neuropathy clinically presenting as the Guillain-Barré syndrome and associated with high titres of anti-ganglioside antibodies highlights the risks of their widespread use before more consistent data on their efficacy become available.

Effect of host age upon the degree of nigrostriatal dopaminergic system recovery following cografts of adrenal medulla and pretransected peripheral nerve

Accumulation of nerve growth factor (NGF) has been reported to occur at the distal stump of pretransected peripheral nerve. We performed adrenal medullary grafts or cografts of adrenal medulla and distal stump of pretransected peripheral nerve into the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated young or aging mice. We subsequently compared the survivability of chromaffin cells and the degree of host dopaminergic (DA) fiber recovery in relation to host age. In both young and aging hosts, adrenal medullary chromaffin cells cografted with pretransected peripheral nerve survived better than those in adrenal grafts alone. Host DA fiber recovery, however, showed less recovery and more restriction around the grafted site in aging compared with young hosts. We conclude that pretransected peripheral nerve can enhance the survivability of cografted chromaffin cells both in young and in aging hosts, but that DA fiber recovery is more limited in aging hosts compared to young hosts.

GM1 ganglioside reduces glutamate toxicity to cortical cells. Lowered LDH release and preserved membrane integrity

As an in vitro model of CNS excitatory amino acid (EAA) injury, rat cortical neuronal cultures were challenged with glutamate (0.5 or 10 mM) and the levels of released lactate dehydrogenase (LDH) were monitored at 1 h, 1, 2, and 7 d. LDH release is correlated with levels of plasma membrane damage. GM1 has been shown to be continuously distributed on the outer surface of CNS cellular membranes. By staining for the distribution of endogenous GM1 ganglioside using cholera toxin/antitoxin immunohistochemistry, we were able to assess morphologically cellular plasma membrane integrity after damage. We used these two measures (LDH and GM1 localization) to study the neuroprotective effects of exogenous GM1 ganglioside to further elucidate its mechanism. Cortical cultures derived from 15-d rat fetuses were subjected to the glutamate challenge for 30 min. Parallel cultures were either pre- or post-treated with 80 microM of GM1. Exposure to 10 mM glutamate caused a highly significant increase in LDH release at 1-48 h. Pretreatment with GM1 reduced the release, whereas posttreatment reduced the LDH release even more. Plasma membrane changes observed by the GM1 immunohistochemistry reflected the LDH release data. All cultures treated with GM1 evidenced substantial structural integrity (continuous staining of GM1 along perikarya and processes) as compared to untreated cultures. These data support our hypothesis that GM1 treatment (pre- and post-) reduces plasma membrane damage.

Ganglioside composition of subcellular fractions, including pre- and postsynaptic membranes, from Torpedo electric organ

Gangliosides were isolated from four subcellular fractions of the electric organ of Torpedo marmorata: synaptosomes, presynaptic membranes, postsynaptic membranes, and synaptic vesicle membranes. This exploited a principal advantage offered by this tissue: facile separation of pre-and postsynaptic elements. Total ganglioside concentration in presynaptic membranes was approximately twice that of synaptosomes and 15 times that of postsynaptic membranes (47.7, 24.4, and 3.21 micrograms of lipid sialic acid per mg protein, respectively). Synaptic vesicle membranes had the highest overall concentration (78.9) relative to protein, but a concentration approximately comparable to that of presynaptic membranes when expressed relative to phospholipid. The thin-layer patterns of these two fractions were similar, both in terms of total pattern and the specific pattern of gangliotetraose structures as revealed by overlay with cholera toxin B subunit; these were notable for the paucity of monosialo structures and the virtual absence of GM1. Postsynaptic membranes, on the other hand, had a significantly higher content of monosialogangliosides including the presence of GM1. The synaptosomal pattern resembled that of the presynaptic membranes and synaptic vesicles. Thus, a clear difference in ganglioside pattern could be discerned between the pre- and postsynaptic elements of the electric organ.

The influence of donor age on cografting of adrenal medulla with pretransected peripheral nerve

Pretransected peripheral nerve has been demonstrated to enhance the survival of cografted adrenal medullary chromaffin cells and the recovery of host dopaminergic (DA) systems in animal models of Parkinson's disease. In the present study, we examined the effect of donor age on survival of cografted chromaffin cells. Adrenal medulla and pretransected peripheral nerve from young (1-month-old) or aging (12-month-old) donors were cografted into the striatum of MPTP-treated young (2-month-old) C57/BL mice. Although chromaffin cell survivability was increased by cografting with pretransected peripheral nerve despite donor age, survivability of chromaffin cells from aging donors was less than that using young donors. Image analysis of striatal DA fibers and chemical analysis of striatal DA showed that cografting with pretransected peripheral nerve enhanced the recovery of striatal DA systems more prominently than adrenal grafting alone. However, this effect was less in mice receiving aging donor tissues compared with mice receiving young donor tissues.

Long-term effects of cografts of pretransected peripheral nerve with adrenal medulla in animal models of Parkinson's disease

Trophic factor supplementation has been reported to enhance the survivability of grafted adrenal chromaffin cells. Because the content of nerve growth factor in the distal stump of a pretransected peripheral nerve increases markedly 1 day after transection, we injected cografts of adrenal medulla with pretransected peripheral nerve into the striata of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice and performed follow-up histological and neurochemical analyses over a 12-month period. Adrenal medullary chromaffin cells cografted with pretransected peripheral nerve survived better than in adrenal grafts alone at 1, 3, and 12 months after transplantation. Host dopaminergic fiber recovery adjacent to the grafts was more prominent in mice with cografts than in mice with adrenal grafts alone at 1 and 3 months after transplantation. Twelve months after transplantation, however, there was no significant difference between the two groups of animals because of the natural recovery of intrinsic dopaminergic fibers from MPTP toxicity. Dopamine concentration in the striata of cografted mice was higher than in mice with adrenal grafts alone at 1 month after transplantation. At 3 and 12 months after transplantation, the natural recovery of dopamine concentration from MPTP toxicity was apparent in both groups of animals and no significant difference was observed between the groups. We conclude that adrenal medullary chromaffin cells can survive for at least 12 months after grafting when cografted with pretransected peripheral nerve. Cografts enhanced the recovery of the host nigrostriatal dopaminergic system up to 3 months after transplantation, but this enhancement was not apparent at 12 months because of the natural recovery of dopaminergic fibers from MPTP toxicity.

Interaction of glycosphingolipids and glycoproteins: thermotropic properties of model membranes containing GM1 ganglioside and glycophorin

High-sensitivity differential scanning calorimetry (DSC) was used to study the mutual interactions between a glycoprotein (human glycophorin, GPA) and a glycosphingolipid (GM1 ganglioside) embedded in large unilamellar vesicles composed of dimyristoylphosphatidylcholine (DMPC). The DSC thermograms exhibited by DMPC/GM1 vesicles, either in the presence or in the absence of GPA, are resolvable into two components. The relative contribution of the minor component, centered at higher temperature, to the total enthalpy and its transition temperature increase with the concentration of the glycolipid embedded in the vesicles. This minor peak, undetectable in the absence of ganglioside, is indicative of the occurrence of lateral phase separation and suggests that GM1 ganglioside-enriched domains are present within the bilayer. At a given concentration of GM1 embedded in the vesicles, the proportion of the phase-separated peak is higher in the presence of GPA, suggesting that the glycoprotein enhances the tendency of GM1 to segregate. Experiments investigating the thermotropic behavior of GPA show that the temperature of irreversible thermal unfolding of the glycoprotein inserted in DMPC vesicles, centered at 65.9 degrees C in the absence of GM1, is shifted to 57.6 degrees C when GM1 is present in the bilayer. These results indicate that, at least in this experimental system, on the one hand, GPA enhances the tendency of the glycolipid to segregate within the membrane, and on the other hand, the glycolipid clusters affect the protein conformation and oligomerization in the membrane.

Normal developmental profiles of CSF gangliotetraose-series gangliosides from neonatal period to adolescence

The normal developmental profiles of cerebrospinal fluid (CSF) gangliosides were examined from the neonatal period to adolescence, using 1 ml of clinically available CSF, by the thin-layer chromatography/enzyme-immunostaining method. The level of total gangliotetraose-series gangliosides, including GM1, GD1a, GT1a, GD1b, GT1b, and GQ1b, increased 3.8-fold from the neonatal period to age 5 years, followed by a plateau, and then a mild decrease. The developmental profiles of individual gangliosides differed from each other. CSF gangliosides change with age, reflecting the maturational changes of the central nervous system gangliosides in situ. CSF ganglioside analysis and this developmental profile might be useful for examining ganglioside aberrations and basic neurochemical mechanisms underlying neurologic disorders, especially age-dependent diseases.

Low levels of CSF gangliotetraose-series gangliosides in West syndrome: implication of brain maturation disturbance

One ml of cerebrospinal fluid (CSF) from each patient with West syndrome and patients from disease control groups were analyzed separately by highly sensitive thin-layer chromatography/enzyme-immunostaining method. The levels (mean +/- S.D.) of GM1, GD1a, sum of GD1b, GT1b, and GQ1b, and total gangliotetraose-series gangliosides in West syndrome patients (n = 14) and in an age-matched control group (n = 14) were as follows: 11.6 +/- 7.8 and 30.9 +/- 12.3 ng/ml CSF, 51.5 +/- 23.2 and 91.7 +/- 41.2 ng/ml CSF, 129.6 +/- 57.6 and 195.9 +/- 123.6 ng/ml CSF, and 192.7 +/- 78.6 and 318.4 +/- 131.6 ng/ml CSF, respectively. The differences were statistically significant except for the sum of GD1b, GT1b, and GQ1b (by 2 sample t test). Because they are abundant in the outer surface of neuronal plasma membranes, gangliosides may play an important role in the transformation of a neuroblast into a functionally mature neuron. Low levels of CSF gangliotetraose-series gangliosides, especially GM1 and GD1a, in patients with West syndrome may suggest a maturation disturbance of the brain from an early developmental stage.

The effects of cytoskeletal altering agents on the surface topography of GM1 in neuro-2A neuroblastoma cell membranes

Neuro-2a murine neuroblastomal cells exposed to exogenous ganglioside undergo increased neuritogenesis in vitro. To determine if the distribution of exogenous ganglioside (GM1) in neuronal membranes is related to neuritogenesis, the surface topography of exogenous ganglioside in these cells was examined by localization with cholera toxin B-FITC. Following exposure to exogenous ganglioside, levels of fluorescent label appeared similar on perikaryal and neuritic surfaces. Scanning electron microscopic studies using protein G-gold to label antibody against exogenous ganglioside confirmed these observations at higher magnification. Within the general labelling pattern, occasionally labelled material was observed which seemed to form short linear arrays. This suggested that elements of the cytoskeleton might be influencing the surface distribution of exogenous ganglioside. To examine this possibility, Neuro-2a cells were exposed to agents known to alter the stability of specific cytoskeletal components, after which the general distribution of exogenous ganglioside was determined. Treatment with Colcemid, which disrupted microtubules, resulted in restriction of most exogenous ganglioside-positive label to the perikaryal surfaces. In contrast, exposure to taxol which enhanced microtubule stability diminished perikaryal fluorescence and increased neuritic labelling. The disruption of cytochalasin D-sensitive microfilaments did not influence the topographic distribution of exogenous ganglioside. Under the experimental conditions employed, mean neuritic lengths for Colcemid- and taxol-treated cells were nearly equal, indicating that altered neuritic length resulting from treatment with cytoskeletal agents was not a major factor in the redistribution of exogenous ganglioside. These studies suggest that microtubules play a role in determining the distribution of recently incorporated ganglioside in neuronal plasma membranes.

Localization of the GM1 ganglioside in the vestibular system using cholera toxin

Cholera toxin is an ubiquitous activator of intracellular adenylate cyclase and is divided in two major components: A and B. The B-component consists of several subunits that specifically bind to the external cell membrane. The receptor for the toxin, the GM1 ganglioside, is concentrated in nervous tissues. The B subunit of the cholera toxin, conjugated to different molecules (i.e., choleragenoid) is therefore a sensitive anatomical tracer and has been used to detect the presence of GM1 in mammalian tissues. Using choleragenoid, unlabeled and labeled with FITC, we have determined the distribution of the GM1 ganglioside in the vestibular system of the chinchilla. Vestibular tissues were fixed in 4% paraformaldehyde in phosphate buffer, decalcified in 10% EDTA and prepared as either whole-mount, surface-preparations, or for radial cryosections. Positive control tissue consisted of binding to normal brain tissues. Negative controls consisted of several treatments: masking of the GM1 receptors with unlabeled choleragenoid, tissue extraction of GM1 using ethanol, and preabsorbing the choleragenoid with bovine GM1. In addition, to exclude staining of glycoproteins that may have a carbohydrate structure similar to GM1, tissues were digested with trypsin prior to choleragenoid exposure. In the vestibular system, a strongly positive reaction was observed in: the sensory stereocilia and supporting cells of the maculae and cristae, epithelial cells of the planum semilunatum, and polygonal cells of the semicircular canal. Positive but less strong reactivity was observed in the sensory cell body of maculae and cristae, nerve fibers, epithelial cells of utricle and ampulla walls and flattened epithelial cells of the semicircular canals. No reactivity was present in the supporting connective tissue cells and fibrils, blood vessels, gelatinous cupula of the cristae ampullaris and statoconial membranes. Brain tissue showed strong choleragenoid reactivity. The negative controls showed no or greatly reduced reactivity to choleragenoid. Trypsin digestion did not decrease reactivity to choleragenoid.

Novel pharmacologic therapies in the treatment of experimental traumatic brain injury: a review

Delayed or secondary neuronal damage following traumatic injury to the central nervous system (CNS) may result from pathologic changes in the brain's endogenous neurochemical systems. Although the precise mechanisms mediating secondary damage are poorly understood, posttraumatic neurochemical changes may include overactivation of neurotransmitter release or re-uptake, changes in presynaptic or postsynaptic receptor binding, or the pathologic release or synthesis of endogenous "autodestructive" factors. The identification and characterization of these factors and the timing of the neurochemical cascade after CNS injury provides a window of opportunity for treatment with pharmacologic agents that modify synthesis, release, receptor binding, or physiologic activity with subsequent attenuation of neuronal damage and improvement in outcome. Over the past decade, a number of studies have suggested that modification of postinjury events through pharmacologic intervention can promote functional recovery in both a variety of animal models and clinical CNS injury. This article summarizes recent work suggesting that pharmacologic manipulation of endogenous systems by such diverse pharmacologic agents as anticholinergics, excitatory amino acid antagonists, endogenous opioid antagonists, catecholamines, serotonin antagonists, modulators of arachidonic acid, antioxidants and free radical scavengers, steroid and lipid peroxidation inhibitors, platelet activating factor antagonists, anion exchange inhibitors, magnesium, gangliosides, and calcium channel antagonists may improve functional outcome after brain injury.

Gangliosides prevent the dimethyl sulphoxide-induced increases in [3H]-noradrenaline release from rat isolated atria

1. In the rat isolated atria labelled with [3H]-noradrenaline ([3H]-NA), the exposure to 1-4% v/v dimethyl sulphoxide (DMSO) during 15 min caused a concentration-dependent increase in the spontaneous outflow of tritiated products, which reached up to 50% with 2% DMSO and up to 100% with 4% DMSO. These effects were entirely prevented by a 2 h in vitro pretreatment with 50 microM bovine brain gangliosides mixture (BBG). 2. The pattern of the spontaneous release of tritiated products was 17.5 +/- 1.9% of [3H]-NA; 38.7 +/- 2.1% of [3H]-3,4-dihydroxyphenylglycol ([3H]-DOPEG); 36.1 +/- 2.4% of [3H]-O-methylated deaminated metabolites ([3H]-OMDA); 4.7 +/- 0.9% of [3H]-3,4-dihydroxymandelic acid ([3H]-DOMA) and 2.9 +/- 0.2% of [3H]-NMN. After 10 min exposure to 2% DMSO, the increase in basal outflow by this agent consisted of 7.4 +/- 2.5% [3H]-NA and 89.0 +/- 3.6% [3H]-DOPEG. The 2 h preincubation with 50 microM BBG protected from the increase of total radioactivity and also from the metabolic alterations caused by DMSO. The BBG per se did not modify either the basal efflux or the metabolic fate of the [3H]-transmitter. 3. In addition to enhancing the spontaneous outflow of radioactivity, the exposure to 2% v/v DMSO increased by 400% the overflow of the [3H]-transmitter elicited by nerve stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuronal ganglioside increases dependent on the neuron--glia interaction in primary culture

Dissociated neuronal cells from rat embryonic hemispheres were cultivated on astroglial layers. The increase in ganglioside content of the cocultures was more rapid than that of neuronal cultures seeded on polylysine surfaces for the first 24 h, and the extent of the increase was greater 7 days after inoculation, probably because of interaction between the preformed astroglial layers and the neuronal cells in vitro. The promoted expression of the a-pathway gangliosides, GM1 and GD1a, was recognized by TLC and the increase in GM1 was immunologically ascertained. The incorporation of 3H-labeled N-acetyl-D-mannosamine into GD3 and b-series gangliosides was elevated for the first 24 h. However, cocultures in which there was no contact between neuronal cells and the astroglial sheet showed no appreciable increase in incorporation. Thus, cell surface changes were induced at the membrane glycolipid level in the neuronal cells by contact with astroglial layers. The synthesis and expression of neuronal gangliosides are discussed in relation to the onset of neuron--glia interaction.

Structural changes of the soleus and the tibialis anterior motoneuron pool during development in the rat

The morphological development of motoneuron pools of two hindlimb muscles of the rat, soleus (SOL) and tibialis anterior (TA), was studied in rats ranging in age between 8 and 30 postnatal days (P8-P30). Motoneurons were retrogradely labelled by injecting a cholera toxin B subunit solution directly into the muscles. This resulted in extensive labelling of motoneurons as well as their dendritic trees. The distribution of cross sectional areas of neuronal somata was determined for both muscles at various ages. Somal size increased considerably between P8 and P12, whereas growth was moderate between P12 and P20. The size distribution of SOL motoneurons was bimodal from P20, whereas the size distribution of TA motoneurons remained largely unimodal. The morphological development of the dendritic tree was studied qualitatively. The development of dendritic arborization within the SOL and the TA motoneuron pool showed major differences. The arborization pattern of dendrites of TA motoneurons was basically multipolar at all ages. In contrast, dendrites of SOL neurons tended to line up with the rostro-caudal axis and became organized in longitudinal bundles from P16 onwards. The relatively late appearance of dendrite bundles in the soleus motoneuron pool suggests that they might be related to the fine-tuning of neuronal activity rather than patterning of motor activity. The occurrence of dendrite bundles in SOL and not in TA motoneuron pools suggests that they may be related to the different afferent organization of this postural muscle or to its tonic activation pattern.

Gangliosides in the human brain development and aging

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.

Gangliosides prevent the inhibition by K-252a of NGF responses in PC12 cells

K-252a, a general kinase inhibitor, selectively blocks the actions of nerve growth factor (NGF) in PC12 cells. Since gangliosides have been reported to modulate neuronal cell responsiveness to NGF and to regulate several protein kinases, the ability of these compounds to reverse the inhibition by K-252a was tested. Parameters at both short- and long-term times following treatment of PC12 cells with NGF were analyzed which are known to be either transcription-dependent or -independent events. Gangliosides were found to completely prevent the inhibition by K-252a of NGF-induced neurite regeneration and c-fos induction, and partially also that of protein kinase N activation. The ganglioside protective effects were concentration-dependent and required the intact molecule. These findings raise the possibility that gangliosides might affect a specific pathway of NGF responses sensitive to inhibition by K-252a.

MPTP-induced parkinsonism: acceleration of biochemical and behavioral recovery by GM1 ganglioside treatment

The effects of GM1 ganglioside administration on functional recovery and recovery of caudate nucleus dopamine levels have been assessed in cats made parkinsonian by administration of the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Cats made severely parkinsonian by MPTP administration began to show spontaneous functional recovery by the third week after MPTP, as had been observed in previous studies with this model. In contrast, cats with similar initial impairment but which received 3 weeks of GM1 ganglioside treatment (30 mg/kg, i.p. daily) showed an accelerated behavioral recovery, showing significant functional improvement after the first week of GM1 treatment and almost normal function by the end of the third week of treatment. The GM1-treated cats had caudate nucleus dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), and HVA levels significantly increased above levels measured in saline-treated MPTP control cats. A second group of cats received MPTP only until the first signs of parkinsonism were observed and thus overall had a less severe initial syndrome than the cats described previously. Again, while all cats showed functional recovery over time, the recovery process was accelerated in GM1-treated cats. GM1 treatment also caused a significant increase in caudate dopamine levels in these cats. These results suggest that GM1 ganglioside administration can result in increased dopamine levels even in the heavily denervated striatum and accelerate functional recovery after an MPTP-induced lesion of the nigrostriatal dopamine system in the cat. This suggests that GM1 or other trophic factor therapies may be fruitful treatment strategies for a disorder of nigrostriatal function such as Parkinson's disease.

Gangliosides of human cerebrospinal fluid in various neurologic diseases

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).

Recovery of motor function after spinal-cord injury--a randomized, placebo-controlled trial with GM-1 ganglioside

BACKGROUND

Spinal-cord injury is devastating; until recently, there was no medical treatment to improve recovery of the initial neurologic deficit. Studies in animals have shown that monosialotetrahexosylganglioside (GM-1) ganglioside enhances the functional recovery of damaged neurons.

METHODS

A prospective, randomized, placebo-controlled, double-blind trial of GM-1 ganglioside was conducted in patients with spinal-cord injuries. Of 37 patients entered into the study, 34 (23 with cervical injuries and 11 with thoracic injuries) completed the test-drug protocol (100 mg of GM-1 sodium salt or placebo intravenously per day for 18 to 32 doses, with the first dose taken within 72 hours of the injury) and a one-year follow-up period. Neurologic recovery was assessed with the Frankel scale (comprising five categories) and the American Spinal Injury Association (ASIA) motor score (a scale of scores from 0 to 100, derived from strength tests of 20 specific muscles, each scored from 0 to 5).

RESULTS

There was a significant difference between groups in the distribution of improvement of Frankel grades from base line to the one-year follow-up (improvement of 0, 1, 2, and 3 grades in 13, 4, 1, and 0 patients, respectively, in the placebo group and 8, 1, 6, and 1 patients, respectively, in the GM-1 group; P = 0.034 by the Cochran-Mantel-Haenszel chi-square test). The GM-1-treated patients also had a significantly greater mean improvement in ASIA motor score from base line to the one-year follow-up than the placebo-treated patients (36.9 vs. 21.6 points; P = 0.047 by analysis of covariance with the base-line ASIA motor score as the covariate). An analysis of individual muscle recoveries revealed that the increased recovery in the GM-1 group was attributable to initially paralyzed muscles that regained useful motor strength rather than to strengthening of paretic muscles.

CONCLUSIONS

This small study provides evidence that GM-1 enhances the recovery of neurologic function after one year. A larger study must be conducted, however, before GM-1 is considered efficacious and safe in treating spinal-cord injury.

The nigrostriatal dopaminergic system in MPTP-treated mice shows more prominent recovery by syngeneic adrenal medullary graft than by allogeneic or xenogeneic graft

Following systemic injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), young (2-month-old) C57BL/6 mice show decreased dopaminergic (DA) nigrostriatal fibers and DA concentration in the striatum. We transplanted syngeneic, allogeneic and xenogeneic adrenal medullary grafts into the striatum of the MPTP-treated young mice and compared the survivability of grafted chromaffin cells and the recovery of intrinsic host DA fibers using computerized image analysis of tyrosine hydroxylase (TH)-immunoreactive (IR) fibers and high performance liquid chromatography with electrochemical detection (LCEC). The grafted syngeneic adrenal chromaffin cells survived better than allogeneic or xenogeneic chromaffin cells, and host DA nigrostriatal fiber recovery was more prominent in mice with a syngeneic graft than in mice with an allogeneic or xenogeneic graft. However, the degree of host fiber recovery in mice with allogeneic or xenogeneic mice was greater than in mice with a sham operation alone, even though the allografts and xenografts had no surviving chromaffin cells. Allografts and xenografts showed prominent rejection responses, with T lymphocyte infiltration in addition to macrophages. We conclude that a syngeneic adrenal graft survives better than an adrenal allograft or xenograft and promotes recovery of the intrinsic host nigrostriatal DA fibers. We also conclude that grafted chromaffin cell survivability influences the degree of host DA fiber recovery following MPTP depletion. Adrenal medullary grafts to Parkinsonian patients are currently under way in a large number of hospitals; we suggest that greater attention be paid to methods which lead to enhanced survival of the grafted chromaffin cells, since survivability might be closely related to the functional recovery of these patients.