Giulia Coarelli

Riluzole in patients with hereditary cerebellar ataxia: a randomised, double-blind, placebo-controlled trial

BACKGROUND Our previous study in patients with cerebellar ataxias of different causes showed significant benefit of riluzole after 8 weeks. We aimed to confirm these results in patients with spinocerebellar ataxia or Friedreichs ataxia in a 1-year trial. METHODS Patients with spinocerebellar ataxia or Friedreichs ataxia (2:1 ratio) from three Italian neurogenetic units were enrolled in this multicentre, double-blind, placebo-controlled trial, and randomly assigned to riluzole (50 mg orally, twice daily) or placebo for 12 months. The randomisation list was computer-generated and a centralised randomisation system was implemented. Participants and assessing neurologists were masked to treatment allocation. The primary endpoint was the proportion of patients with improved Scale for the Assessment and Rating of Ataxia (SARA) score (a drop of at least one point) at 12 months. An intention-to-treat analysis was done. This trial is registered at ClinicalTrials.gov, number NCT01104649. FINDINGS Between May 22, 2010, and Feb 25, 2013, 60 patients were enrolled. Two patients in the riluzole group and three in the placebo group withdrew their consent before receiving treatment, so the intention-to-treat analysis was done on 55 patients (19 with spinocerebellar ataxia and nine with Friedreichs ataxia in the riluzole group, and 19 with spinocerebellar ataxia and eight with Friedreichs ataxia in the placebo group). The proportion with decreased SARA score was 14 (50%) of 28 patients in the riluzole group versus three (11%) of 27 in the placebo group (OR 8·00, 95% CI 1·95-32·83; p=0·002). No severe adverse events were recorded. In the riluzole group, two patients had an increase in liver enzymes (less than two times above normal limits). In two participants in the riluzole group and two participants in the placebo group, sporadic mild adverse events were reported. INTERPRETATION Our findings lend support to the idea that riluzole could be a treatment for cerebellar ataxia. Longer studies and disease-specific trials are needed to confirm whether these findings can be applied in clinical practice. FUNDING Agenzia Italiana del Farmaco.

Effects of Bacille Calmette-GuÉrin after the first demyelinating event in the CNS

Objective: To evaluate Bacille Calmette-Guérin (BCG) effects after clinically isolated syndromes (CIS). Methods: In a double-blind, placebo-controlled trial, participants were randomly assigned to receive BCG or placebo and monitored monthly with brain MRI (6 scans). Both groups then entered a preplanned phase with IM interferon-β-1a for 12 months. From month 18 onward, the patients took the disease-modifying therapies (DMTs) that their neurologist considered indicated in an open-label extension phase lasting up to 60 months. Results: Of 82 randomized subjects, 73 completed the study (33 vaccinated and 40 placebo). During the initial 6 months, the number of cumulative lesions was significantly lower in vaccinated people. The relative risks were 0.541 (95% confidence interval [CI] 0.308–0.956; p = 0.03) for gadolinium-enhancing lesions (the primary endpoint), 0.364 (95% CI 0.207–0.639; p = 0.001) for new and enlarging T2-hyperintense lesions, and 0.149 (95% CI 0.046–0.416; p = 0.001) for new T1-hypointense lesions. The number of total T1-hypointense lesions was lower in the BCG group at months 6, 12, and 18: mean changes from baseline were −0.09 ± 0.72 vs 0.75 ± 1.81 (p = 0.01), 0.0 ± 0.83 vs 0.88 ± 2.21 (p = 0.08), and −0.21 ± 1.03 vs 1.00 ± 2.49 (p = 0.02). After 60 months, the cumulative probability of clinically definite multiple sclerosis was lower in the BCG + DMT arm (hazard ratio = 0.52, 95% CI 0.27–0.99; p < 0.05), and more vaccinated people remained DMT-free (odds ratio = 0.20, 95% CI 0.04–0.93; p = 0.04). Conclusions: Early BCG may benefit CIS and affect its long-term course. Classification of evidence: BCG, as compared to placebo, was associated with significantly reduced development of gadolinium-enhancing lesions in people with CIS for a 6-month period before starting immunomodulating therapy (Class I evidence).

Methylation-dependent PAD2 upregulation in multiple sclerosis peripheral blood

Background: Peptidylarginine deiminase 2 (PAD2) and peptidylarginine deiminase 4 (PAD4) are two members of PAD family which are over-expressed in the multiple sclerosis (MS) brain. Through its enzymatic activity PAD2 converts myelin basic protein (MBP) arginines into citrullines – an event that may favour autoimmunity – while peptidylarginine deiminase 4 (PAD4) is involved in chromatin remodelling. Objectives: Our aim was to verify whether an altered epigenetic control of PAD2, as already shown in the MS brain, can be observed in peripheral blood mononuclear cells (PBMCs) of patients with MS since some of these cells also synthesize MBP. Methods: The expression of most suitable reference genes and of PAD2 and PAD4 was assessed by qPCR. Analysis of DNA methylation was performed by bisulfite method. Results: The comparison of PAD2 expression level in PBMCs from patients with MS vs. healthy donors showed that, as well as in the white matter of MS patients, the enzyme is significantly upregulated in affected subjects. Methylation pattern analysis of a CpG island located in the PAD2 promoter showed that over-expression is associated with promoter demethylation. Conclusion: Defective regulation of PAD2 in the periphery, without the immunological shelter of the blood–brain barrier, may contribute to the development of the autoimmune responses in MS.

A "candidate-interactome" aggregate analysis of genome-wide association data in multiple sclerosis

Though difficult, the study of gene-environment interactions in multifactorial diseases is crucial for interpreting the relevance of non-heritable factors and prevents from overlooking genetic associations with small but measurable effects. We propose a “candidate interactome” (i.e. a group of genes whose products are known to physically interact with environmental factors that may be relevant for disease pathogenesis) analysis of genome-wide association data in multiple sclerosis. We looked for statistical enrichment of associations among interactomes that, at the current state of knowledge, may be representative of gene-environment interactions of potential, uncertain or unlikely relevance for multiple sclerosis pathogenesis: Epstein-Barr virus, human immunodeficiency virus, hepatitis B virus, hepatitis C virus, cytomegalovirus, HHV8-Kaposi sarcoma, H1N1-influenza, JC virus, human innate immunity interactome for type I interferon, autoimmune regulator, vitamin D receptor, aryl hydrocarbon receptor and a panel of proteins targeted by 70 innate immune-modulating viral open reading frames from 30 viral species. Interactomes were either obtained from the literature or were manually curated. The P values of all single nucleotide polymorphism mapping to a given interactome were obtained from the last genome-wide association study of the International Multiple Sclerosis Genetics Consortium & the Wellcome Trust Case Control Consortium, 2. The interaction between genotype and Epstein Barr virus emerges as relevant for multiple sclerosis etiology. However, in line with recent data on the coexistence of common and unique strategies used by viruses to perturb the human molecular system, also other viruses have a similar potential, though probably less relevant in epidemiological terms.

Multiple sclerosis etiology: beyond genes and environment

Multiple sclerosis (MS) is a disorder of the CNS with inflammatory and neurodegenerative components. The etiology is unknown, but there is evidence for a role of both genetic and environmental factors. Among the heritable factors, MHC class II genes are strongly involved, as well as genes coding for others molecules of immunological relevance, genes controlling neurobiological pathways and genes of unknown function. Among nonheritable factors, many infectious agents (mainly viruses) and environmental factors (e.g., smoke, sun exposition and diet) seem to be of etiologic importance. Here, we report and discuss recent findings in MS on largely unexplored fields: the alternative splicing of mRNAs and regulatory noncoding RNAs, the major sources of transcriptome diversity; and epigenetic changes with special attention paid to DNA methylation and histone acetylation, the main regulators of gene expression.

Epstein-Barr virus nuclear antigen-1 B-cell epitopes in multiple sclerosis twins.

Background: Compared with quantitative observations, the search for qualitative changes that may characterize the immune response to Epstein–Barr virus (EBV) in multiple sclerosis (MS) has been less intense. Objective: To examine the B-cell epitopes of antibodies against the Epstein–Barr nuclear antigen-1 (EBNA-1) and their relevance for MS, through a study in disease-discordant identical twins. Methods: We evaluated the antibodies to all unique, maximally overlapping octapeptides of EBNA-1 in 12 pairs of monozygotic (MZ) twins (9 MS-discordant, 3 healthy), 3 non-twin patients and 2 healthy subjects. All except one of the patients were untreated. The EBV serology of these individuals had been assessed in advance using commercially available and in-house enzyme-linked immunosorbent assay (ELISA) kits, including assays for antibodies against select peptides of EBNA-1: EBNA-72 (GAGGGAGAGG) and EBNA-206 (EADYFEYHQEGGPDGE). Results: The glycine–alanine rich domain of EBNA-1 was immunodominant in all subjects. Compared with healthy individuals, and similarly to what has been described in infectious mononucleosis (IM) patients, affected co-twins and non-twin patients had a significantly increased response to another EBNA-1 epitope (aa. 401–411). Conclusion: In a study that controls for confounders, our data focus an EBNA-1 specificity that may be associated with MS pathogenesis.

Serum elements and oxidative status in clinically isolated syndromes Imbalance and predictivity

Background: Metals are suspected of being involved in the pathogenesis of various neurologic diseases. We previously found a complex imbalance in serum chemical elements and oxidative status in patients with clinically definite multiple sclerosis (CDMS). Objective: To understand whether this imbalance affects people with clinically isolated syndrome (CIS) and, if so, whether it predicts conversion to CDMS. Methods: We studied 22 chemical elements and the oxidative status in 49 patients with CIS, 49 patients with CDMS, and 49 healthy donors (HD). Univariate and multivariate approaches were used to identify profiles for each group. A logistic regression analysis was used to identify the predictive potential of baseline data (elements, oxidative status, and MRI findings) for conversion to CDMS over 36 months. Results: Several elements and oxidative status values differed significantly among the 3 groups. Discriminant analysis revealed a major contribution of Ca, Fe, Sn, Zn, serum antioxidant capacity, and serum oxidative status, which resulted in distinct profiles (the prediction of group membership was 96% [cross-validated 92%] for HD, 92% [cross-validated 92%] for CDMS, and 90% [cross-validated 86%] for CIS). A weighted combination of element concentrations and oxidative status values, adjusting for all other predictors, would predict a reduction in the risk of conversion to CDMS within 3 years (odds ratio 0.37; 95% confidence interval 0.18–0.76; p = 0.007), thereby proving more effective than MRI at baseline. Conclusions: The peculiar imbalance in serum elements and oxidative status that characterizes patients with CIS and may predict conversion to CDMS warrants studies on larger sample sizes.

Low cancer prevalence in polyglutamine expansion diseases.

Objective: Polyglutamine (PolyQ) diseases are dominantly transmitted neurologic disorders, caused by coding and expanded CAG trinucleotide repeats. Cancer was reported retrospectively to be rare in patients with PolyQ diseases and we aimed to investigate its prevalence in France. Methods: Consecutive patients with Huntington disease (HD) and spinocerebellar ataxia (SCA) were questioned about cancer, cardiovascular diseases, and related risk factors in 4 university hospitals in Paris, Toulouse, Strasbourg, and Montpellier. Standardized incidence ratios (SIR), based on age- and sex-adjusted rate of the French population, were assessed for different types of cancer. Results: We questioned 372 patients with HD and 134 patients with SCA. SIR showed significantly reduced risk of cancer in HD: 23 observed cases vs 111.05 expected ones (SIR 0.21, 95% confidence interval [CI] 0.13–0.31), as well as in SCA: 7 observed cases vs 34.73 expected (SIR 0.23, 95% CI 0.08–0.42). This was surprising since risk behavior for cancer was increased in these patients, with significantly greater tobacco and alcohol consumption in patients with HD vs patients with SCA (p < 0.0056). There was no association between CAG repeat size and cancer or cardiovascular disease. However, in patients with HD, skin cancers were more frequent than expected (5 vs 0.98, SIR 5.11, 95% CI 1.65–11.95). Conclusions: There was a decreased cancer rate in PolyQ diseases despite high incidence of risk factors. Intriguingly, skin cancer incidence was higher, suggesting a crosstalk between neurodegeneration and skin tumorigenesis.

Evidence for Detrimental Cross Interactions between Reactive Oxygen and Nitrogen Species in Leber's Hereditary Optic Neuropathy Cells

Here we have collected evidence suggesting that chronic changes in the NO homeostasis and the rise of reactive oxygen species bioavailability can contribute to cell dysfunction in Lebers hereditary optic neuropathy (LHON) patients. We report that peripheral blood mononuclear cells (PBMCs), derived from a female LHON patient with bilateral reduced vision and carrying the pathogenic mutation 11778/ND4, display increased levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS), as revealed by flow cytometry, fluorometric measurements of nitrite/nitrate, and 3-nitrotyrosine immunodetection. Moreover, viability assays with the tetrazolium dye MTT showed that lymphoblasts from the same patient are more sensitive to prolonged NO exposure, leading to cell death. Taken together these findings suggest that oxidative and nitrosative stress cooperatively play an important role in driving LHON pathology when excess NO remains available over time in the cell environment.

Riluzole in patients with hereditary cerebellar ataxia – Authors' reply

I read with interest Rhonda Voskuhl and colleagues’ report of a phase 2 trial of the combination of estriol and glatiramer acetate for women with relapsing-remitting multiple sclerosis, and Annette Langer-Gould’s Commentary on the Article. Ho wever, the authors did not seem to be aware Authors’ reply We thank Rick Brandsma and colleagues for their comments on our choice of a 1-point reduction in the Scale for the Assessment and Rating of Ataxia (SARA) as a cutoff for ataxia improvement. As discussed in the Article, this option was largely justifi ed by the yearly progression reported for the patients we included in the study (mainly with spinocerebellar ataxia types 1 and 2, or Friedreich’s ataxia). Long-term disease progression in spinocerebellar ataxia types 1, 2, 3, and 6 was reported in The Lancet Neurology shortly after the publication of our Article; the increases in SARA score per year were 2·11 for type 1, 1·49 for type 2, 1·56 for type 3, and 0·80 for type 6. These increases suggest that a one-point reduction in the SARA score after 1 year for patients with spinocerebellar ataxia type 1 represents a gain of three points with respect to the expected progression of disease. If we had analysed our data with a reduction cutoff of two points at 12 months, we would still have noted a signifi cant diff erence in favour of riluzole treatment (nine of 28 cases vs zero of 27 cases; p=0·001). We thank Jonas Alex Morales Saute and Laura Bannach Jardim for their comments about the possibility that riluzole works as a diseasemodifying therapy and on the design of randomised clinical trials in rare orphan diseases such as the hereditary ataxias. Overall, we endorse their suggestions, especially the usefulness of a delayed start design and the need for open-label phases in which all patients would receive the active drug for longer periods after a positive short-duration randomised trial. Because of regulatory and economic hurdles, open-label phases were diffi cult to plan in our populations of patients: only three patients remained on riluzole therapy from the fi rst trial (one died from multisystem atrophy, but two patients are doing well, without adverse eff ects or progression, after 5 years of follow-up). The future plan for the therapeutic development of riluzole should take into account three points: fi rst, that the drug seems to be effective in different forms of cerebellar ataxia; second, Alexandra Durr’s suggestion of aiming for a large sample size of patients with homogeneous forms of ataxias; and third, the usefulness of designing a randomised clinical trial with a long follow-up and planning an open-label phase for the placebo group.