Monosialoganglioside in subarachnoid hemorrhage

GM1 Ganglioside Is A Key Factor in Maintaining the Mammalian Neuronal Functions Avoiding Neurodegeneration

Many species of ganglioside GM1, differing for the sialic acid and ceramide content, have been characterized and their physico-chemical properties have been studied in detail since 1963. Scientists were immediately attracted to the GM1 molecule and have carried on an ever-increasing number of studies to understand its binding properties and its neurotrophic and neuroprotective role. GM1 displays a well balanced amphiphilic behavior that allows to establish strong both hydrophobic and hydrophilic interactions. The peculiar structure of GM1 reduces the fluidity of the plasma membrane which implies a retention and enrichment of the ganglioside in specific membrane domains called lipid rafts. The dynamism of the GM1 oligosaccharide head allows it to assume different conformations and, in this way, to interact through hydrogen or ionic bonds with a wide range of membrane receptors as well as with extracellular ligands. After more than 60 years of studies, it is a milestone that GM1 is one of the main actors in determining the neuronal functions that allows humans to have an intellectual life. The progressive reduction of its biosynthesis along the lifespan is being considered as one of the causes underlying neuronal loss in aged people and severe neuronal decline in neurodegenerative diseases. In this review, we report on the main knowledge on ganglioside GM1, with an emphasis on the recent discoveries about its bioactive component.

Gangliosides: Treatment Avenues in Neurodegenerative Disease

Gangliosides are cell membrane components, most abundantly in the central nervous system (CNS) where they exert among others neuro-protective and -restorative functions. Clinical development of ganglioside replacement therapy for several neurodegenerative diseases was impeded by the BSE crisis in Europe during the 1990s. Nowadays, gangliosides are produced bovine-free and new pre-clinical and clinical data justify a reevaluation of their therapeutic potential in neurodegenerative diseases. Clinical experience is greatest with monosialo-tetrahexosyl-ganglioside (GM1) in the treatment of stroke. Fourteen randomized controlled trials (RCTs) in overall >2,000 patients revealed no difference in survival, but consistently superior neurological outcomes vs. placebo. GM1 was shown to attenuate ischemic neuronal injuries in diabetes patients by suppression of ERK1/2 phosphorylation and reduction of stress to the endoplasmic reticulum. There is level-I evidence from 5 RCTs of a significantly faster recovery with GM1 vs. placebo in patients with acute and chronic spinal cord injury (SCI), disturbance of consciousness after subarachnoid hemorrhage, or craniocerebral injuries due to closed head trauma. In Parkinson's disease (PD), two RCTs provided evidence of GM1 to be superior to placebo in improving motor symptoms and long-term to result in a slower than expected symptom progression, suggesting disease-modifying potential. In Alzheimer's disease (AD), the role of gangliosides has been controversial, with some studies suggesting a "seeding" role for GM1 in amyloid β polymerization into toxic forms, and others more recently suggesting a rather protective role in vivo. In Huntington's disease (HD), no clinical trials have been conducted yet. However, low GM1 levels observed in HD cells were shown to increase cell susceptibility to apoptosis. Accordingly, treatment with GM1 increased survival of HD cells in vitro and consistently ameliorated pathological phenotypes in several murine HD models, with effects seen at molecular, cellular, and behavioral level. Given that in none of the clinical trials using GM1 any clinically relevant safety issues have occurred to date, current data supports expanding GM1 clinical research, particularly to conditions with high, unmet medical need.

An overview of new pharmacological treatments for cerebrovascular dysfunction after experimental subarachnoid hemorrhage

Cerebral vasospasm and the resulting cerebral ischemia occurring after subarachnoid hemorrhage (SAH) are still responsible for the considerable morbidity and mortality in patients affected by cerebral aneurysms. Mechanisms contributing to the development of vasospasm, abnormal reactivity of cerebral arteries and cerebral ischemia after SAH have been intensively investigated in recent years. It has been suggested that the pathogenesis of vasospasm is related to a number of pathological processes, including endothelial damage, smooth muscle cell contraction resulting from spasmogenic substances generated during lyses of subarachnoid blood clots, changes in vascular responsiveness and inflammatory or immunological reactions of the vascular wall. A great deal of experimental and clinical research has been conducted in an effort to find ways to prevent these complications. However, to date, the main therapeutic interventions remain elusive and are limited to the manipulation of systemic blood pressure, alteration of blood volume or viscosity, and control of arterial dioxide tension. Even though no single pharmacological agent or treatment protocol has been identified which could prevent or reverse these deadly complications, a number of promising drugs have been investigated. Among these is the hormone erythropoietin (EPO), the main regulator of erythropoiesis. It has recently been found that EPO produces a neuroprotective action during experimental SAH when its recombinant form (rHuEPO) is systemically administered. This topic review collects the relevant literature on the main investigative therapies for cerebrovascular dysfunction after aneurysmal SAH. In addition, it points out rHuEPO, which may hold promise in future clinical trials to prevent the occurrence of vasospasm and cerebral ischemia after SAH.

Monosialoganglioside (GM1) attenuates the behavioural effects of long-term haloperidol administration in supersensitive rats

In the present study we investigated the effects of co-administration of GM(1) (15.0 mg/kg, twice daily, for 30 days) and haloperidol (1.0 mg/kg, twice daily, for 30 days), as well as the effects of a 5-day treatment with this dose of GM(1) after withdrawal from haloperidol in rats. The animals were evaluated in the open-field test and apomorphine-induced stereotyped behaviour. The results show that GM(1) was able to attenuate dopaminergic supersensitivity evaluated by the locomotion frequency at 24 and 48 h after the withdrawal from haloperidol. On the other hand, rearing frequency was changed neither by haloperidol nor by GM(1.) In haloperidol-treated rats immobility time differs from 30 min observation session in comparison with the following sessions after the withdrawal from neuroleptic. Apomorphine-induced stereotyped behaviour produced a significant increase in scores of haloperidol-withdrawn rats. GM(1) did not modify the haloperidol effects and did not change the dopamine receptor affinity to apomorphine 100 h from abrupt neuroleptic withdrawal.

The Sygen multicenter acute spinal cord injury study

STUDY DESIGN

Randomized, double-blind, sequential, multicenter clinical trial of two doses of Sygen versus placebo.

OBJECTIVES

To determine efficacy and safety of Sygen in acute spinal cord injury.

SUMMARY OF BACKGROUND DATA

An earlier, single-center trial in 28 patients showed an improvement (50.0% vs. 7.1%, P = 0.034) in marked recovery with Sygen.

METHODS

Standard clinical trial techniques.

RESULTS

The prospectively planned analysis at the prespecified endpoint time for all patients was negative. There was a significant effect in all patients in the primary outcome variable (the percentage of marked recovery) at week 8, the end of the dosing period. There was a significant effect in all patients in the time at which marked recovery is first achieved. Restricted to severity Group B, which has small sample size, the primary efficacy analysis showed a trend but did not reach significance. There is a large, consistent and, at some time points, significant effect in the primary outcome variable in the nonoperated patients through week 26. The American Spinal Injury Association motor, light touch, and pinprick scores showed a consistent trend in favor of Sygen, as also did bowel function, bladder function, sacral sensation, and anal contraction. The less severely injured patients appeared to have a greater beneficial drug effect. Evidence against an effect of Sygen was minimal and scattered.

CONCLUSIONS

Although not proven in the primary efficacy analysis of this trial, Sygen appears to be beneficial in patients with severe spinal cord injury.

Gangliosides for acute ischaemic stroke

BACKGROUND

Gangliosides may have a protective effect on the central and peripheral nervous systems.

OBJECTIVES

The objective of this review was to assess the effect of exogenous gangliosides in acute ischaemic stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group trials register (last searched: March 1999) and contacted drug companies.

SELECTION CRITERIA

Randomised trials of gangliosides compared with placebo or standard treatment in people with definite or presumed ischaemic stroke. Trials were included if people were randomised within 15 days of symptom onset and if mortality data were available.

DATA COLLECTION AND ANALYSIS

One reviewer applied the inclusion criteria. Two reviewers independently extracted the data. Trial quality was assessed.

MAIN RESULTS

Eleven trials involving 2257 people were included. All the trials tested purified monosialoganglioside GM1. Only three trials described the randomisation procedure. Follow-up was between 15 to 180 days. Death at the end of follow-up showed no significant difference (odds ratio 0.91, 95% confidence interval 0.73 to 1.14). There was no difference shown between early (within 48 hours) and delayed treatment. For disability, two trials showed an improved Barthel index score with gangliosides (weighted mean difference 8.6, 95% confidence interval 1.2 to 16.0). In two trials, eight patients experienced adverse effects that led to discontinuation of ganglioside treatment, seven had skin reactions and one developed Guillain-Barré syndrome.

REVIEWER'S CONCLUSIONS

There is not enough evidence to conclude that gangliosides are beneficial in acute stroke. Caution is warranted because of reports of sporadic cases of Guillain-Barré syndrome after ganglioside therapy.

Response of the damaged dopamine system to GM1 and semisynthetic gangliosides: effects of dose and extent of lesion

GM1 ganglioside, administered to young C57/B16J mice with moderate (approx 85%) 1-methyl-4-phenyl-1,2,3,6-terahydropyridine (MPTP)-induced striatal dopamine depletions, caused a dose-dependent increase in striatal dopamine levels. This effect was maximal between 7.0 and 30.0 mg/kg and was not apparent at higher and lower doses of GM1. GM1 ganglioside treatment had no effect on striatal dopamine levels in mice with more extensive lesions of the dopamine system (i.e. approx 93% loss of striatal dopamine). The semisynthetic ganglioside derivative LIGA 20, administered orally, also increased striatal dopamine levels in moderately lesioned animals, albeit at lower doses than GM1. LIGA 20 administration also resulted in increased striatal dopamine levels in animals with more extensive dopamine lesions, where GM1 had no effect. These results show that both GM1 and its semisynthetic derivative LIGA 20 can partially restore striatal dopamine levels in MPTP-treated mice and that LIGA 20 is more potent and not subject to the same dose-limiting effects as GM1.

Advances in the early management of patients with head injury

The last decade has seen continual improvement in our skills of visualizing and diagnosing the many types of human head injury. As we continue to unravel the complex biochemistry and molecular changes caused by trauma, we expect to find new methods and agents to enhance the extracellular milieu of injured but salvageable neurons and supporting cells, resulting in continued improvement in outcome for patients with severe head injury.

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 parenteral administration of GM1 on cytokines and anti-ganglioside antibody patterns. Preliminary report in normal human individuals

To assess the effects of monosialoganglioside GM1 on some immunological parameters, 12 healthy men were treated with 100 mg GM1 i.m. daily for 15 days. Before and after treatment, the following were studied: (1) serum levels of antibodies against GM1, asialo-GM1 (aGM1), GM2 and GD1b; (2) serum levels of interleukin (IL)-1 beta, IL-2, soluble IL-2 receptor (sIL-2R), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma); (3) IL-1 beta and TNF-alpha production by peripheral blood monocytes (PBMO). Anti-ganglioside antibody and cytokine serum levels were not affected by exogenous GM1 administration with the exception of a transient increase in anti-GM1 antibody titer observed in one subject. In addition, no inhibition of IL-1 beta and TNF-alpha production by PBMO was observed. These preliminary data do not support a potential immunogenic or immunomodulatory function for in vivo administered GM1.