Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0016719 (Friedreich's ataxia)
 2,098 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A review concerning the characteristics of the cerebellar serotoninergic system is presented. In rat, cat and oppossum, the perikarya of origin are located in the brain stem raphe nuclei and in other brainstem structures. The projections to the cerebellar layers and deep nuclei include synaptic connections, but also non synaptic terminals, especially in a diffuse cortical plexus. Serotoninergic receptors have been described: 5-HT1B in the molecular layer and 5-HT2 in the inferior olive. Serotonin exerts neurophysiological effects on several target cells, directly or indirectly, presynaptically or postsynaptically. A modulatory effect on Purkinje cells is well documented. In thiamine deprived animals, a specific serotoninergic cerebellar syndrome includes a selective degeneration of the serotoninergic cerebellar system, an increase of the 5-HIAA cerebellar values and an exaggerated serotoninergic turnover. In human heredoataxias (Friedreich's ataxia and cerebellar cortical atrophy), serotoninergic disturbances have been observed in the CSF, including low 5-HIAA values and an increased serotoninergic turnover. Therapeutic results have been obtained with L-5-HTP, a precursor of serotonin, in several conditions presenting cerebellar ataxia. L-5-HTP resistance of olivopontocerebellar atrophies may be explained by the destruction of serotonin-sensitive target cells, especially Purkinje cells.
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PMID:The cerebellar serotoninergic system and its possible involvement in cerebellar ataxia. 833 97

Actual therapeutic assays in spinocerebellar ataxias, i.e. in Friedreich's ataxia (FA) and olivopontocerebellar atrophy (OPCA) are discussed in relation to (i) the serotoninergic theory; (ii) the excitotoxic action of glutamate; and (iii) cerebrospinal fluid thiamine deficiency in ataxic patients. Data from the literature show that neurochemical deficiencies arising from cerebellar damage in both FA and OPCA patients are multiple. Assays of replacement and neuroprotective therapeutics with a single drug have produced controversial data or mildly effective results. Consequently, it is hypothesized that a drug cocktail, i.e. L-5-hydroxytryptophan, thiamine and amantadine hydrochloride, would be more beneficial. This cocktail proved to be useful in open studies, improving respiratory disorders in FA patients. More powerful inhibitors of N-methyl-D aspartate receptor channels should be tried initially in animal experiments.
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PMID:The treatment of spinocerebellar ataxias: facts and hypotheses. 984 65

Cerebellar syndrome is one of the most disabling developments in multiple sclerosis (MS). In neurodegenerative disorders, cerebellar syndrome is thought to be related to a neurochemical deficit of 5-hydroxytryptamine (5-HT). Previous studies found that a levorotatory form of 5-hydroxytryptophan, a 5-HT precursor, and ondansetron, a 5-HT(3) receptor antagonist, decreased cerebellar symptoms in Friedreich's ataxia and MS. We studied the effect of another 5-HT(3) receptor antagonist, dolasetron mesilate, on cerebellar syndrome in MS patients.Thirty-four MS patients were included in a placebo-controlled double-blind crossover study. They received a single dose of intravenous dolasetron mesilate or placebo. A quantitative evaluation of cerebellar syndrome using the nine-hole peg test and an ataxia score comprising static and kinetic parameters were performed before and after each treatment. No statistical difference was observed in the dolasetron mesilate group, compared with the placebo group. There was, however, inter-individual variability in the treatment response. This double-blind study on cerebellar syndrome in MS patients did not confirm the positive effect of dolasetron mesilate suggested by previous studies.
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PMID:Double-blind crossover study with dolasetron mesilate, a 5-HT3 receptor antagonist in cerebellar syndrome secondary to multiple sclerosis. 1458

The confirmed pharmacological treatment of cerebellar ataxia is still lacking. In a recent preliminary trial, we showed that D-cycloserine, a partial NMDA allosteric agonist, may relieve the symptoms. In this paper, major clinical trials to relieve ataxic symptoms are reviewed. Previous studies showed some efficacy of physostigmine in ataxic patients. However, physostigmine did not improve the ataxia in a recent double-blind crossover study. The replacement therapy of the deficient cholinergic system with choline or choline derivatives was tried in patients with Friedreich's ataxia and other ataxic patients, but the result was not definitive. A levorotatory form of hydroxytryptophan (a serotonin precursor), a serotoninergic 5-HT1A agonist, a serotoninergic 5-HT3 antagonist, and a serotonin reuptake inhibitor were also used for the therapy for ataxia. In a double-blind randomized study, buspirone, a 5-HT1A agonist was active in cerebellar ataxia, but the effect is partial and not major. The effects of the studies with the other serotoninergic drugs were not consistent. The effect of sulfamethoxazole-trimethoprim therapy in spinocerebellar ataxia type3/Machado-Joseph disease (MJD) was reported, although the therapy improved spasticity or rigidity, rather than ataxia. In contrast to previous studies, sulfamethoxazole-trimethoprim therapy in MJD had no effect in a 2001 double-blind crossover study. The thyrotropin-releasing hormone, D-cycloserine, and acetazolamide for SCA6 may have some efficacy. However, a well-designed double-blind crossover trial is needed to confirm the effect.
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PMID:Pharmacological treatments of cerebellar ataxia. 1523 78

The aim of this study was to determine the effectiveness and safety of available treatment alternatives for degenerative ataxias (DA). We systematically reviewed studies that assess pharmacological, rehabilitative, or psychological treatments in patients with DA. Studies were included if they fulfilled prespecified criteria. All included clinical trials were scored for methodological quality. Main outcome measures were clinical status of neurological disorder, adverse events, and patient-based factors. Twenty-five studies were included. Most studies were of small sample sizes, wide age variations, and low scientific validity. Only one study gave information on physical rehabilitation and none on psychological therapy. The remaining 24 studies reported on the effects of different pharmacological treatments. Outcomes such as functional capacity and psychological functioning of patients were evaluated by few studies. Some evidence supports that 5-hydroxytryptophan is more effective than placebo improving neurological symptoms in patients with Friedreich ataxia (FA), olivopontocerebellar atrophy, or cerebellar atrophy. Idebenone is more effective than placebo for halting and reversing the hypertrophic cardiomyopathy associated with FA, but it seems unable to improve neurological semiology. Limited evidence for other therapies was found. No relevant side effects for drugs that shown some degree of effectiveness were reported. Availability of quality studies to evaluate the safety and efficacy of treatments for most DA is scarce. No valid information on the actual value of physical rehabilitation and psychological support as treatments for DA is available. Further investigations with improved trial designs are necessary.
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PMID:Effectiveness and safety of treatments for degenerative ataxias: a systematic review. 1941 36