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Gilbert Bensimon

Publications and source records attributed to Gilbert Bensimon.

6 recordsLinked to original sources
PubMed2006

Bone marrow transplantation attenuates the myopathic phenotype of a muscular mouse model of spinal muscular atrophy.

Bone marrow (BM) transplantation was performed on a muscular mouse model of spinal muscular atrophy that had been created by mutating the survival of motor neuron gene (Smn) in myofibers only. This model is characterized by a severe myopathy and progressive loss of muscle fibers leading to paralysis. Transplantation of wild-type BM cells following irradiation at a low dose (6 Gy) improved motor capacity (+85%). This correlated with a normalization of myofiber number associated with a higher number of regenerating myofibers (1.6-fold increase) and an activation of CD34 and Pax7 satellite cells. However, BM cells had a very limited capacity to replace or fuse to mutant myofibers (2%). These data suggest that BM transplantation was able to attenuate the myopathic phenotype through an improvement of skeletal muscle regeneration of recipient mutant mice, a process likely mediated by a biological activity of BM-derived cells. This hypothesis was further supported by the capacity of muscle protein extracts from transplanted mutant mice to promote myoblast proliferation in vitro (1.6-fold increase). In addition, a tremendous upregulation of hepatocyte growth factor (HGF), which activates quiescent satellite cells, was found in skeletal muscle of transplanted mutants compared with nontransplanted mutants. Eventually, thanks to the Cre-loxP system, we show that BM-derived muscle cells were strong candidates harboring this biological activity. Taken together, our data suggest that a biological activity is likely involved in muscle regeneration improvement mediated by BM transplantation. HGF may represent an attractive paracrine mechanism to support this activity.

Animals↗
PubMed2004

Xaliproden in amyotrophic lateral sclerosis: early clinical trials.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting motor neurons. We report the safety and functional efficacy results of a double-blind, placebo-controlled phase II study of xaliproden, a non-peptidic compound with growth factor activities, in 54 ALS patients treated for up to 32 weeks. In order to overcome the interference of mortality with functional assessment in exploratory studies, we identified from our ALS database prognostic factors to establish a staging process for selection pf patients: age, disease duration, slopes of deterioration of the functional scores calculated during the two months prior to the inclusion, and the value at entry of the forced vital capacity (FVC). The six months intent-to-treat analysis showed no statistically significant effect but a trend in favour of 2 mg xaliproden compared to placebo for reduction in the rate of deterioration of FVC, limbs functional score, and manual muscle testing score (MMT). The results in the completer analysis showed a significant 43% slower rate of deterioration in FVC (P=0.046) in xaliproden-treated patients but not in functional and MMT scores. These results support the use of a staging process to select suitable patients for phase II studies, and suggest that xaliproden may have potential effects in ALS and deserve further study.

Adult↗
PubMed2004

Efficacy and safety of xaliproden in amyotrophic lateral sclerosis: results of two phase III trials.

Amyotrophic lateral sclerosis (ALS) is a relentlessly progressive and fatal motor neuron disease. We carried out two randomized, double-blind, placebo-controlled, multi-centre, multi-national studies with xaliproden (a drug with neurotrophic effect) to assess drug efficacy and safety at two doses. Patients with clinically probable or definite ALS of more than 6 months and less than 5 years duration were randomly assigned to placebo, 1 mg or 2 mg xaliproden orally once daily as monotherapy in Study 1 (n=867); or to the same regimen with addition of riluzole 50 mg bid background therapy in Study 2 (n=1210 patients). The two primary endpoints were defined as: 1. Time to death, tracheostomy, or permanent assisted ventilation (DTP), and 2. Time to vital capacity (VC)<50% or DTP before (log-rank test) and after adjustment using a Cox proportional hazard model for prespecified prognostic factors. Secondary endpoints were rates of change of various functional measures. In Study 1, primary outcome measures did not reach statistical significance. For the 2 mg group, for time to VC<50% analysis (without DTP) a significant 30% RRR was obtained (95% confidence interval [CI]: 8.46, P=0.009). In Study 2, no significant results were obtained. However, there was a trend in favour of add-on 1 mg dose xaliproden vs. placebo (RRR 15% [-6.31, ns] for time to VC<50%; RRR 12% [CI: -6.27, ns] for time to VC<50% or DTP). Adjusted RR ratios were consistently more favourable for the xaliproden groups. Tolerability was good, and dose-dependent side effects were largely associated with the serotonergic properties of xaliproden. An effect of xaliproden on functional parameters, especially VC, was noted. Although this effect did not reach statistical significance, xaliproden had a small effect on clinically noteworthy aspects of disease progression in ALS.

Adult↗
PubMed2004

The tolerability of riluzole in the treatment of patients with amyotrophic lateral sclerosis.

Riluzole is the only disease-modifying drug approved for the treatment of amyotrophic lateral sclerosis (ALS), in which it has been demonstrated to extend survival. The overall tolerability of riluzole is good and the drug can be used in all patients with ALS except those with elevated transaminase levels or active liver disease. The most frequently encountered adverse events (AEs) that appear to be attributed to riluzole are asthenia and nausea, observed in 18 and 15% of patients taking riluzole in the randomised clinical trial programme, respectively. These same AEs, albeit at a lower frequency, are also reported in Phase IV observational studies and in pharmacovigilance surveys. No unexpected AE clearly related to riluzole has emerged in the seven years that riluzole has been in extensive use in ALS patients. The most important potential safety issue with riluzole is hepatic impact with elevations of transaminases. Serum alanine aminotransferase levels more than three times the upper limit of normal are observed in 10 - 15% of patients. For this reason, strict monitoring of liver enzymes is recommended in patients with ALS taking riluzole, and treatment is contraindicated in subjects with elevated transaminases before the start of treatment. There is a suspicion that riluzole may, in rare cases, cause neutropenia, and physicians should be vigilant towards this risk.

Aged↗
PubMed2002

Glutamate levels in cerebrospinal fluid in amyotrophic lateral sclerosis: a reappraisal using a new HPLC method with coulometric detection in a large cohort of patients.

Glutamate is involved in the degeneration of motor neurons in amyotrophic lateral sclerosis (ALS). However, the aetiology of ALS appears heterogeneous, leading to the possibility that patient subgroups with different pathophysiology may exist. The concentration of glutamate in cerebrospinal fluid (CSF) is measured using a new HPLC method with coulometric detection in a large cohort of ALS patients and controls: 377 ALS patients, 88 neurological patients and 18 normal controls. In ALS patients, and only in these subjects, the existence of two groups was observed, one with normal glutamate concentrations and one (40.8% of ALS patients) with high glutamate concentrations. High glutamate concentrations were correlated with a spinal onset of the disease, more impaired limb function and a higher rate of muscle deterioration. These results suggest that elevations of CSF glutamate concentrations could reflect the intensity of cell insult in the spinal cord. It remains to be determined if the group of patients with high CSF glutamate concentrations represents a specific subgroup of patients in terms of mechanism of disease, or only in terms of the spatial extent of motor neuron insult.

Age Factors↗