Giorgia Querin

A genome-wide association meta-analysis identifies a novel locus at 17q11.2 associated with sporadic amyotrophic lateral sclerosis

Identification of mutations at familial loci for amyotrophic lateral sclerosis (ALS) has provided novel insights into the aetiology of this rapidly progressing fatal neurodegenerative disease. However, genome-wide association studies (GWAS) of the more common (∼90%) sporadic form have been less successful with the exception of the replicated locus at 9p21.2. To identify new loci associated with disease susceptibility, we have established the largest association study in ALS to date and undertaken a GWAS meta-analytical study combining 3959 newly genotyped Italian individuals (1982 cases and 1977 controls) collected by SLAGEN (Italian Consortium for the Genetics of ALS) together with samples from Netherlands, USA, UK, Sweden, Belgium, France, Ireland and Italy collected by ALSGEN (the International Consortium on Amyotrophic Lateral Sclerosis Genetics). We analysed a total of 13 225 individuals, 6100 cases and 7125 controls for almost 7 million single-nucleotide polymorphisms (SNPs). We identified a novel locus with genome-wide significance at 17q11.2 (rs34517613 with P = 1.11 × 10(-8); OR 0.82) that was validated when combined with genotype data from a replication cohort (P = 8.62 × 10(-9); OR 0.833) of 4656 individuals. Furthermore, we confirmed the previously reported association at 9p21.2 (rs3849943 with P = 7.69 × 10(-9); OR 1.16). Finally, we estimated the contribution of common variation to heritability of sporadic ALS as ∼12% using a linear mixed model accounting for all SNPs. Our results provide an insight into the genetic structure of sporadic ALS, confirming that common variation contributes to risk and that sufficiently powered studies can identify novel susceptibility loci.

Right hemisphere dysfunction and emotional processing in ALS: an fMRI study.

Emotional processing may be abnormal in amyotrophic lateral sclerosis (ALS). Our aim was to explore functional anatomical correlates in the processing of aversive information in ALS patients. We examined the performance of nine non-demented ALS patients and 10 healthy controls on two functional MRI (fMRI) tasks, consisting of an emotional attribution task and a memory recognition task of unpleasant versus neutral stimuli. During the emotional decision task, subjects were asked to select one of three unpleasant or neutral words. During the memory task, subjects were asked to recognize words presented during the previous task. Controls showed, as expected, greater activation in the right middle frontal gyrus during selection of unpleasant than neutral words, and a greater activation mainly in right-sided cerebral areas during the emotional recognition task. Conversely, patients showed a general increase in activation of the left hemisphere, and reduced activation in right hemisphere in both emotional tasks. Such findings may suggest extra-motor neurodegeneration involving key circuits of emotions, mostly negative, commonly involved in FTD.

Pilot trial of clenbuterol in spinal and bulbar muscular atrophy

Objective: To test the efficacy and tolerability of clenbuterol in patients with spinal and bulbar muscular atrophy (SBMA). Methods: Twenty patients with a diagnosis of SBMA were given oral clenbuterol (0.04 mg/d) for 12 months. The primary efficacy end point was the change from baseline of the walking distance covered in 6 minutes at 12 months. Secondary end points included the change over time in muscle strength assessed with the Medical Research Council scale, the revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R), and forced vital capacity values. Safety was assessed by a series of laboratory and instrumental tests, as well as reporting of adverse events. Results: Sixteen patients completed the study. There was a significant and sustained increase in walking distance covered in 6 minutes and forced vital capacity between the baseline and the 12-month assessments (p < 0.001). No differences were recorded in Medical Research Council or ALSFRS-R scores between baseline and follow-up assessments. Serious side effects, including those on heart function, were absent. A significant increase in serum creatine kinase levels was observed. Conclusions: Our findings suggest a positive effect of clenbuterol on SBMA disease progression. Classification of evidence: This study provides Class IV evidence that clenbuterol is effective in improving motor function in SBMA.

ALS risk but not phenotype is affected by ataxin-2 intermediate length polyglutamine expansion

TDP-43 is the major disease protein in amyotrophic lateral sclerosis (ALS).1 Recently, ataxin-2, a polyglutamine (polyQ) protein mutated in spinocerebellar ataxia type 2 (SCA2),2 has been shown to interfere with TDP-43 toxicity in ALS animal models and to abnormally localize in ALS spinal cord neurons.3 An increased risk for ALS and an earlier age at disease onset were observed in patients with an intermediate-length CAG expansion (24–33) [(CAG)24–33] in ataxin-2 encoding gene ( ATXN2 ). To test the hypothesis that ATXN2 (CAG)24–33 expansion is a clinical modifier in ALS, we determined the length of the polyQ expansion in 247 patients with ALS and correlated clinical phenotype in the (CAG)24–33 expansion patients with those with a CAG expansion below 24 repeats. ### Methods. Considered in the present study were patients with ALS according to the El Escorial criteria4 evaluated at the ALS Clinic of Padova from January 2004 to August 2010. Patient data entered included sex, age and site of onset (bulbar or spinal), disease duration at ALS diagnosis, forced vital capacity (FVC, expressed as percentage of the expected value) at first assessment, survival defined as the time from onset to …

Non-neural phenotype of spinal and bulbar muscular atrophy: results from a large cohort of Italian patients

Objective To carry out a deep characterisation of the main androgen-responsive tissues involved in spinal and bulbar muscular atrophy (SBMA). Methods 73 consecutive Italian patients underwent a full clinical protocol including biochemical and hormonal analyses, genitourinary examination, bone metabolism and densitometry, cardiological evaluation and muscle pathology. Results Creatine kinase levels were slightly to markedly elevated in almost all cases (68 of the 73; 94%). 30 (41%) patients had fasting glucose above the reference limit, and many patients had total cholesterol (40; 54.7%), low-density lipoproteins cholesterol (29; 39.7%) and triglyceride (35; 48%) levels above the recommended values. Although testosterone, luteinising hormone and follicle-stimulating hormone values were generally normal, in one-third of cases we calculated an increased Androgen Sensitivity Index reflecting the presence of androgen resistance in these patients. According to the International Prostate Symptom Score (IPSS), 7/70 (10%) patients reported severe lower urinal tract symptoms (IPSS score >19), and 21/73 (30%) patients were moderately symptomatic (IPSS score from 8 to 19). In addition, 3 patients were carriers of an indwelling bladder catheter. Videourodynamic evaluation indicated that 4 of the 7 patients reporting severe urinary symptoms had an overt prostate-unrelated bladder outlet obstruction. Dual-energy X-ray absorptiometry scan data were consistent with low bone mass in 25/61 (41%) patients. Low bone mass was more frequent at the femoral than at the lumbar level. Skeletal muscle biopsy was carried out in 20 patients and myogenic changes in addition to the neurogenic atrophy were mostly observed. Conclusions Our study provides evidence of a wide non-neural clinical phenotype in SBMA, suggesting the need for comprehensive multidisciplinary protocols for these patients.

Androgen-dependent impairment of myogenesis in spinal and bulbar muscular atrophy

Spinal and bulbar muscular atrophy (SBMA) is an inherited neuromuscular disease caused by expansion of a polyglutamine (polyQ) tract in the androgen receptor (AR). SBMA is triggered by the interaction between polyQ-AR and its natural ligands, testosterone and dihydrotestosterone (DHT). SBMA is characterized by the loss of lower motor neurons and skeletal muscle fasciculations, weakness, and atrophy. To test the hypothesis that the interaction between polyQ-AR and androgens exerts cell-autonomous toxicity in skeletal muscle, we characterized the process of myogenesis and polyQ-AR expression in DHT-treated satellite cells obtained from SBMA patients and age-matched healthy control subjects. Treatment with androgens increased the size and number of myonuclei in myotubes from control subjects, but not from SBMA patients. Myotubes from SBMA patients had a reduced number of nuclei, suggesting impaired myotube fusion and altered contractile structures. The lack of anabolic effects of androgens on myotubes from SBMA patients was not due to defects in myoblast proliferation, differentiation or apoptosis. DHT treatment of myotubes from SBMA patients increased nuclear accumulation of polyQ-AR and decreased the expression of interleukin-4 (IL-4) when compared to myotubes from control subjects. Following DHT treatment, exposure of myotubes from SBMA patients with IL-4 treatment rescued myonuclear number and size to control levels. This supports the hypothesis that androgens alter the fusion process in SBMA myogenesis. In conclusion, these results provide evidence of an androgen-dependent impairment of myogenesis in SBMA that could contribute to disease pathogenesis.

Diagnostic and Prognostic Biomarkers in Amyotrophic Lateral Sclerosis: Neurofilament Light Chain Levels in Definite Subtypes of Disease

Importance A clearer definition of the role of neurofilament light chain (NFL) as a biomarker in amyotrophic lateral sclerosis (ALS) is needed. Objectives To assess the ability of NFL to serve as a diagnostic biomarker in ALS and the prognostic value of cerebrospinal fluid NFL in patients with ALS. Design, Setting, and Participants In this single-center, retrospective, longitudinal study, disease progression was assessed by the ALS Functional Rating Score–Revised and the ALS Milano-Torino Staging system at baseline and 6, 12, 24, and 36 months. Cerebrospinal fluid samples were obtained from 176 patients admitted to the Department of Neurosciences of the University of Padua, Padova, Italy, from January 1, 2010, through February 29, 2016. Patients with ALS underwent ambulatory follow-up at the same department. Main Outcomes and Measures Levels of NFL. Results The study included 94 patients with ALS (64 men [36.4%] and 30 women [17.0%]; median age, 62.5 years), 20 patients with frontotemporal dementia (FTD) (8 men [4.5%] and 12 women [6.8%]; median age, 65 years), 18 patients with motor neuropathies (14 men [8.0%] and 4 women [2.3%]; median age, 63 years), and 44 controls (24 men [13.6%] and 20 women [11.4%]; median age, 54 years). Log-transformed NFL (log[NFL]) concentrations were higher in the ALS and FTD groups compared with the motor neuropathies and control groups (hazard ratio [HR], 2.45; 95% CI, 1.66-3.61; P < .001). Patients with typical ALS (HR, 1.0 [reference]), progressive bulbar palsy (HR, 1.48; 95% CI, 0.58-3.75; P = .41), and upper motor neuron dominant ALS (HR, 0.12; 95% CI, 0.02-0.61; P = .01) had higher levels of NFL than did those with flail arm or leg syndrome (HR, 0.28; 95% CI, 0.08-0.10; P = .049) and progressive muscular atrophy (HR, 0.17; 95% CI, 0.22-1.36; P = .10). There was an inverse correlation between log[NFL] concentration and overall survival (HR, 2.45; 95% CI, 1.66-3.61; P < .001). There was no evidence of different log[NFL] concentrations and survival in genetic ALS. Conclusions and Relevance This study confirms the role of NFL as a biomarker in ALS. Elevation in NFL levels in patients with upper motor neuron involvement and FTD might reflect the corticospinal tract degeneration. Low NFL levels in patients with lower motor neuron signs might be a prognostic indicator of milder phenotypes of disease.

Psychopathological features and suicidal ideation in amyotrophic lateral sclerosis patients.

Psychopathological diagnosis has become increasingly important in amyotrophic lateral sclerosis (ALS), since the recent emphasis on the comprehensive management and end-of-life decisions. Rorschach test is the third most commonly used psychological instrument worldwide and can offer a different approach from self-reporting questionnaires, mainly providing information on issues of which individuals may be unaware or unwilling to admit to. Forty-two ALS patients underwent a psychopathological assessment with the Rorschach test. Psychopathological data were also correlated with skeletal muscle strength as measured by MRC scale and functional evaluation as ALSFRSr and FVC values. Psychopathological features, including suicidial ideation, were more frequent in the recently diagnosed ALS patients. These features were observed to be different according to the kind of functional impairment. Rorschach test may be an useful tool to assess psychopathological features in ALS. Results of our study highlight the need of an early psychopathological diagnosis and specific psychotherapeutic treatment in patients with ALS.

Genetic Variation in KIFAP3 Is Associated with an Upper Motor Neuron-Predominant Phenotype in Amyotrophic Lateral Sclerosis

Background: Some authors have recently reported that the CC genotype of single-nucleotide polymorphism (SNP) rs1541160 mapping within the kinesin-associated protein 3 (KIFAP3) gene is associated with increased survival in sporadic amyotrophic lateral sclerosis (sALS). Objective and Methods: The relationship between the rs1541160 genotype and several clinical features of 228 ALS patients was evaluated with the intent of assessing any association between the ALS phenotype and KIFAP3. The SNP rs1541160 within the KIFAP3 expression profile was investigated using real-time PCR in a group of 6 patients harboring the CC genotype and in 12 patients harboring the TT genotype. Results: Analysis of our patients’ clinical features showed that almost half of those with the CC genotype were classified as having upper motor neuron-predominant ALS (UMN-ALS). Conversely, there was an approximately 10% frequency of UMN-ALS in both the TT and the TC patient groups as well as in the entire cohort considered as a whole (p < 0.005). The SNP rs1541160 genotype did not appear to have any effect on patient survival or on KIFAP3 expression. Conclusions: The incidence of the UMN-ALS phenotype in the CC patients of this cohort supports the hypothesis that the SNP rs1541160 within the KIFAP3 gene is a potential modifier of the ALS phenotype.

TUBA4A gene analysis in sporadic amyotrophic lateral sclerosis: identification of novel mutations

Viviana Pensato • Cinzia Tiloca • Lucia Corrado • Cinzia Bertolin • Valentina Sardone • Roberto Del Bo • Daniela Calini • Jessica Mandrioli • Giuseppe Lauria • Letizia Mazzini • Giorgia Querin • Mauro Ceroni • Roberto Cantello • Stefania Corti • Barbara Castellotti • Giulia Solda • Stefano Duga • Giacomo P. Comi • Cristina Cereda • Gianni Soraru • Sandra D’Alfonso • Franco Taroni • Christopher E. Shaw • John E. Landers • Nicola Ticozzi • Antonia Ratti • Cinzia Gellera • Vincenzo Silani • The SLAGEN Consortium