Alberto Calvi

Expression and Genetic Analysis of MicroRNAs Involved in Multiple Sclerosis

Evidence underlines the importance of microRNAs (miRNAs) in the pathogenesis of multiple sclerosis (MS). Based on the fact that miRNAs are present in human biological fluids, we previously showed that miR-223, miR-23a and miR-15b levels were downregulated in the sera of MS patients versus controls. Here, the expression levels of these candidate miRNAs were determined in peripheral blood mononuclear cells (PBMCs) and the serum of MS patients, in addition to three genotyped single nucleotide polymorphisms (SNPs). Mapping in the genomic regions of miR-223, miR-23a and miR-15b genes, 399 cases and 420 controls were tested. Expression levels of miR-223 and miR-23a were altered in PBMCs from MS patients versus controls. Conversely, there were no differences in the expression levels of miR-15b. A significantly decreased genotypic frequency of miR-223 rs1044165 T/T genotype was observed in MS patients. Moreover, the allelic frequency of miR-23a rs3745453 C allele was significantly increased in patients versus controls. In contrast, there were no differences in the distribution of miR-15b SNP. In conclusion, our results suggest that miR-223 and miR-23a could play a role in the pathogenesis of MS. Moreover, miR-223 rs1044165 polymorphism likely acts as a protective factor, while miR-23a rs3745453 variant seems to act as a risk factor for MS.

Effect of fingolimod treatment on circulating miR-15b, miR23a and miR-223 levels in patients with multiple sclerosis

MicroRNAs (miRNAs) have recently found to be dysregulated in serum from multiple sclerosis (MS) patients. Cell free circulating miR-15b, -23a and 223 levels were analyzed by Real Time PCR in a cohort consisting of 30 serum samples from Relapsing Remitting MS patients at baseline (T0) and after three, six, nine and twelve months (T1, T2, T3, T4) after starting the treatment. A down-regulation of miRNA levels in patients at T0 compared with controls was present (p<0.001). MiRNA levels slightly increased at T1 and this trend reached the statistical significance at T2 vs T0 and remains stable at T3 and T4. Our preliminary results suggest that aberrant levels of circulating miRNAs are recovered in fingolimod treated MS patients. Circulating miRNAs profiling could thus represent an easy detectable biomarker of disease and response to treatment.

CSF β-amyloid and white matter damage: a new perspective on Alzheimer’s disease

Objective To assess the connection between amyloid pathology and white matter (WM) macrostructural and microstructural damage in demented patients compared with controls. Methods Eighty-five participants were recruited: 65 with newly diagnosed Alzheimer’s disease (AD), non-AD dementia or mild cognitive impairment and 20 age-matched and sex-matched healthy controls. β-amyloid1-42 (Aβ) levels were determined in cerebrospinal fluid (CSF) samples from all patients and five controls. Among patients, 42 had pathological CSF Aβ levels (Aβ(+)), while 23 had normal CSF Aβ levels (Aβ(−)). All participants underwent neurological examination, neuropsychological testing and brain MRI. We used T2-weighted scans to quantify WM lesion loads (LLs) and diffusion-weighted images to assess their microstructural substrate. Non-parametric statistical tests were used for between-group comparisons and multiple regression analyses. Results We found an increased WM-LL in Aβ(+) compared with both, healthy controls (p=0.003) and Aβ(−) patients (p=0.02). Interestingly, CSF Aβ concentration was the best predictor of patients’ WM-LL (r=−0.30, p<0.05) when using age as a covariate. Lesion apparent diffusion coefficient value was higher in all patients than in controls (p=0.0001) and correlated with WM-LL (r=0.41, p=0.001). In Aβ(+), WM-LL correlated with WM microstructural damage in the left peritrigonal WM (p<0.0001). Conclusions WM damage is crucial in AD pathogenesis. The correlation between CSF Aβ levels and WM-LL suggests a direct link between amyloid pathology and WM macrostructural and microstructural damage.

The Novel GRN g.1159_1160delTG Mutation is Associated with Behavioral Variant Frontotemporal Dementia

Mutations in progranulin gene (GRN) are a common cause of autosomal dominant frontotemporal lobar degeneration and are associated with a wide phenotypic heterogeneity. Here, we describe two probands with behavioral variant frontotemporal dementia with a novel mutation in this gene (1159_1160delTG). Both had a positive family history for dementia and showed atypical features at imaging. Their progranulin plasma levels were undetectable, and the mutation was not present in cDNA, suggesting haploinsufficiency. Progranulin levels were low even in asymptomatic carriers of the variant. Results described enlarge current knowledge on genetic causes of the disease and clinical characteristics of carriers.

Word and Picture Version of the Free and Cued Selective Reminding Test (FCSRT): Is There Any Difference?

The Free and Cued Selective Reminding Test (FCSRT) is the most commonly used neuropsychological test to evaluate episodic memory. Two variants of FCSRT exist, using the recall of words (FCSRT-w) or pictures (FCSRT-p). Fourteen patients with mild cognitive impairment underwent neuropsychological evaluation and brain magnetic resonance. We found differences in FCSRT-w and FCSRT-p variants scores. FCSRT-p was correlated with atrophy in areas involved in visual stimuli processing while FCSRT-w was correlated to hippocampal atrophy. Our study suggests that FCSRT-w and FCSRT-p scores are not equivalent, but a larger cohort of patients is needed to validate these results.

Partial recovery after severe immune reconstitution inflammatory syndrome in a multiple sclerosis patient with progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a rare and severe complication of natalizumab therapy in patients with multiple sclerosis and it may be accompanied by immune reconstitution inflammatory syndrome (IRIS). Here, we describe a case of abnormally severe IRIS, which occurred 2 months after natalizumab-associated PML in a 38-year-old woman affected by multiple sclerosis. The patient was John Cunningham virus-positive and was treated for 21 months when she developed PML. The subsequent IRIS diffusely afflicted the brain, producing edema and signs of intracranial hypertension, with a clinically severe form compromising the state of consciousness, requiring intensive care and high-dosage steroid treatment. Nevertheless, she survived and partially recovered. There is still difficulty in differentiating PML progression from IRIS onset and there is not a clear description in the literature about different clinical forms of IRIS, prognostic factors and guidelines to properly treat this complication in order to reduce the residual disability of the patient surviving this treatment complication.

LncRNAs expression profile in peripheral blood mononuclear cells from multiple sclerosis patients

LncRNA PCR arrays containing 90 common LncRNAs were used to screen lncRNA expression levels in PBMC from a discovery population of patients with MS. Data from discovery and replications cohorts showed a generalized dysregulation of lncRNA levels in MS patients compared with controls. MALAT1, MEG9, NRON, ANRIL, TUG1, XIST, SOX2OT, GOMAFU, HULC, BACE-1AS were significantly downregulated in MS patients in comparison with controls. Therefore, we performed a validation analysis in an independent cohort of Belgian origin. In this study, NRON and TUG1 downregulations in MS patients compared with controls were confirmed (p ≤ .05 and p ≤ .0001 respectively), whereas considering the other lncRNAs, the statistical threshold was not reached. LncRNAs profiling could thus represent a new challenge in the research of easy detectable biomarkers of disease susceptibility and progression.

Neurophysiological Profile, Walking Performance Tests and Self-Reported Questionnaires in Spastic Patients with MS: A Pilot Study

Nabiximols is currently being used as an add-on therapeutic option to treat severe forms of multiple sclerosis (MS) spasticity, especially in the progressive phase of the disease. The aim of this exploratory study is to evaluate the response to Nabiximols therapy and modifications in neurophysiological profile, improvement in walking performance tests and self-reported questionnaires, as possible further outcome measures of spasticity. 8 MS patients were recruited to start Nabiximols therapy, all responders in terms of significant reduction of numerical rating scale (NRS). The patients underwent measurements of lower limbs H-reflex and F wave before treatment (baseline) and after 4 and 8 weeks (T1 and T2) of treatment with Nabiximols titrated to optimal dosage, along with timed 25-foot walk test (T25FW), six-minute walk test (6MWT) and questionnaires evaluating subjectively reported spasticity, fatigue and walking abilities (MSSS-88, MFIS, MSWS-12). A reduction of the latencies of the H-reflex and F wave was found between baseline and at T1, which was more strongly confirmed at T2 (P=0.04 relative to H-reflex; P=0.05 and P=0.007 relative to minimal and medium F wave latencies). A significant reduction in time to perform T25FW test was observed between baseline and after treatment (P<0.05), together with a trend towards an improvement in the 6MWT. After the treatment period significant variations in part of the self-reported questionnaires administered were found, as a reduction of the MSSS-88 and MFIS total scores (P<0.05). Nabiximols treatment might have an impact in different objective measurements, including neurophysiological and walking performance tests and self-reported questionnaires. Latencies reduction in H-reflex and F-wave may reflect modifications in the generation of spasticity mechanisms. Moreover, spasticity control is related with an improvement in quality of life of MS patients as it may have a positive impact on walking abilities and reduction of global perception of fatigue.