[Show abstract][Hide abstract] ABSTRACT: Mycobacterium avium subsp. paratuberculosis (MAP) infections have been recently linked to multiple sclerosis in Sardinian population, with amino acid sequence 301-309 of MAP2694 protein possessing a high antigenic potential. Peptide presentation by HLA protein is an important step in adaptive immune response to pathogens, which is linked to stable peptide-HLA complex. In this study we focus on two predisposing (*15:01, *03:01) and two protective (*16:01, *15:02) HLA-DRB1 proteins in Sardinian population. We investigate in detail their binding characteristics to the MAP2694-derived peptide, with the aim to link disease susceptibility to protein structural-dynamical features and ultimately to molecular mechanisms contributing to the disease. Using dihedral angle principal components analysis, we observe distinct chemical configurations and dynamics of the HLA peptide binding, between the predisposing and protective proteins upon binding. The difference persists in the collective motion of residues near the amino-terminal region of the peptide-binding groove involving polymorphic HLA-DRB1 residue 86. Buried surface area and binding energy estimations also support the protein distinction, suggesting a preferential peptide binding towards the predisposing proteins. Finally, water dynamics analysis in the binding groove highlighted the role of slow water molecules in bridging H-bond interactions between the protein and peptide residues. Our work demonstrates the ability of molecular simulations to characterize MAP peptide binding to the proteins associated with multiple sclerosis in Sardinia. Overall, this distinction between the predisposing and protective proteins can be associated to a biological mechanism that functionally contributes to disease onset in predisposed individuals.
New Journal of Chemistry 12/2014; · 3.16 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
Familial lipodystrophies are rare inherited disorders associated with redistribution of body fat and development of dyslipidemia, insulin resistance and diabetes. We previously reported two siblings with unusual late-onset familial partial lipodystrophy in whom heretofore known causative genes had been excluded. We hypothesized they had a mutation in a novel lipodystrophy gene.
Our approach centred on whole exome sequencing of the patients' DNA, together with genetic linkage analysis and a bioinformatic prioritization analysis. All candidate variants were assessed in silico and available family members were genotyped to assess segregation of mutations.
Our prioritization algorithm led us to a novel homozygous nonsense variant, namely p.Ala507fsTer563 in the LIPE gene encoding hormone sensitive lipase, an enzyme that is differentially expressed in adipocytes and steroidogenic tissues. Pathogenicity of the mutation was supported by bioinformatic analyses and variant cosegregation within the family.
We have identified a novel nonsense mutation in LIPE, which likely explains the lipodystrophy phenotype observed in these patients.
The Canadian journal of cardiology 12/2014; · 3.12 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: It has been shown that different genes could be associated with distinctive clinical and radiological phenotypes of FTD. TARDBP gene has been described worldwide in few cases of FTD so its phenotype is still unclear. The objective is to study the clinical and radiological characteristics of TARDBP-related FTD. In the present study, we report clinical, neuropsychological and radiological features of five new Sardinian non-related cases of FTD carriers of the p.A382T TARDBP mutation. Furthermore, we reviewed non-related FTD cases with TARDBP mutations previously described in literature. The p.A382T missense mutation of TARDBP was present in the 21.7 % of familial cases of our FTD cohort (5/23) and in no one of the sporadic patients. 3 of 5 patients showed a temporal variant FTD and 4/5 a predominant temporal involvement at MRI. The review of the literature of FTD cases with TARDBP mutations showed that in 5 of 16 cases, the clinical phenotype was consistent with temporal variant of FTD or semantic dementia (31 %) and in 7 of 16 cases neuroimaging showed predominant temporal lobe involvement (43.7 %). Our study further supports the pathogenetic role of TARDBP mutations in pure FTD and in the full spectrum of FTD/ALS. The presence of a predominant temporal lobe involvement in a high percentage of FTD mutated patients with a peculiar clinical pattern could be useful in the differential diagnosis with other forms of dementia/FTD both sporadic and familial.
[Show abstract][Hide abstract] ABSTRACT: A large number of reports indicate the association of Epstein-Barr virus (EBV), and Mycobacterium avium subsp. paratuberculosis (MAP) with multiple sclerosis (MS).
To gain a better understanding of the role of these two pathogens, we investigated the host response induced by selected antigenic peptides.
We examined both humoral and cell-mediated responses against peptides deriving from EBV tegument protein BOLF1, the MAP_4027 and the human interferon regulatory factor 5 (IRF5424-434) homolog in several MS patients and healthy controls (HCs).
Antibodies against these peptides were highly prevalent in MS patients compared to HCs. Concerning MS patients, BOLF1305-320, MAP_402718-32 and IRF5424-434 peptides were able to induce mainly Th1-related cytokines secretion, whereas Th2-related cytokines were down-regulated. Flow cytometry analyses performed on a subset of MS patients highlighted that these peptides were capable of inducing the release of pro-inflammatory cytokines: IFN-γ and TNF-α by CD4+ and CD8+ T lymphocytes, and IL-6 and TNF-α by CD14+ monocyte cells.
Our data demonstrated that both EBV and MAP epitopes elicit a consistent humoral response in MS patients compared to HCs, and that the aforementioned peptides are able to induce a T-cell-mediated response that is MS correlated.
[Show abstract][Hide abstract] ABSTRACT: In our study we analysed clinical and neuropsychological data in a cohort of 57 Sardinian patients with FTD (55 apparently unrelated and two belonging to the same family), who underwent genetic screening for the C9orf72 mutation. Eight out of 56 patients were found positive for the C9orf72 mutation representing 14% of the entire cohort and 31.6% of the familial cases (6/19). C9orf72 mutated patients differed from the other FTD cases of the cohort for a younger age of onset, higher frequency of familial history for FTD and higher prevalence of delusional psychotic symptoms and hallucinations. In the neuropsychological assessment, C9orf72 mutated patients differed from non-mutated for the high frequency of visuospatial dysfunction regarding constructional apraxia (p = 0.02). In conclusion, our study confirms that Sardinian FTD patients have peculiar genetic characteristics and that C9orf72 mutated patients have a distinctive clinical and neuropsychological profile that could help differentiate them from other FTD patients. In our cohort we found that constructional apraxia, rarely reported in FTD, can properly discriminate between C9orf72 mutated and non-mutated patients and contribute to broaden the neuropsychological profile in frontotemporal dementia associated with this mutation.
[Show abstract][Hide abstract] ABSTRACT: Background
The purpose is to measure the worsening of the Quality of Life (QoL) in people with Multiple Sclerosis (MS) and the concomitant role of co-morbid Major Depressive Disorder (MDD) and Bipolar Disorder (BD), the latter not yet studied even though it was found strictly associated with MS.
Cases: 201 consecutive-MS-patients. Controls: 804 sex-and-age-matched subjects without MS, randomly selected from an epidemiological database study. Psychiatric diagnoses according to DSM-IV were determined by physicians using structured interview tools (ANTAS-SCID). Bipolar Spectrum Disorders were identified by Mood Disorders Questionnaire (MDQ). QoL was measured by SF-12.
MS was the strongest determinant in worsening the QoL in the overall sample. Both MDD and BD type-II lifetime diagnoses were significantly associated with a poorer quality of life in the total sample as in cases of MS. In MS the impairment of the QoL attributable to BD type-II was even greater than that in MDD.
The MS diagnosis was made differently in cases and controls. Although this may have produced false negatives in controls, it would have reinforced the null hypothesis (no role of MS in worsening the QoL); therefore, it does not invalidate the study.
MDD as well BD type-II are co-determinants in worsening QoL in MS. Clinicians should consider depressive symptoms as well as the hypomanic and mixed components in MS. Additional research is required to confirm our results and further clarify the manner in which BD and the mixed symptoms of BD type-II may affect awareness of both the underlying disease and psychiatric component and finally to what extent they impact treatment adherence with the available therapies for MS.
Journal of Affective Disorders 10/2014; 167:192–197. · 3.30 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A critical aspect of multiple sclerosis (MS) treatments is understanding the effect of disease-modifying drugs (DMDs) on the long-term risk of disability and whether the effect is related to disability at start of treatment.
[Show abstract][Hide abstract] ABSTRACT: Bacillus Calmette-Guérin (BCG) and Mycobacterium avium subspecies paratuberculosis (MAP) have been associated with Multiple Sclerosis (MS). Clinical data indicates that BCG vaccination exerts anti-inflammatory effects in MS; conversely, MAP is thought to be one of the possible infectious factors responsible of MS through a molecular mimicry mechanism.
A peptide-based indirect ELISA was used to detect antibodies against the encephalitogenic myelin oligodendrocyte glycoprotein (MOG)35–55 epitope, and two mycobacterial peptides sharing sequence homology with the latter: MAP_2619c352–361/BCG_1224355–364 and BCG_3329c64–74. Among 40 MS patients and 39 healthy volunteers included in the study, only MOG35–55 was capable of inducing a significantly higher humoral response in MS subjects compared to controls. Indeed, 11 out of 40 MS subjects (27.5%) and only 2 out of 39 controls (5%) were antibody-positive for MOG35–55 (p = 0.01, AUC = 0.65).
These findings strengthen the importance of MOG35–55 in MS pathogenesis. The MAP and BCG MOG-homologues epitopes investigated were not recognized in MS patients. Overall, the results allow us concluding that sharing homology of linear epitopes is necessary but not sufficient toinduce antibody-mediated cross-reactivity.
Journal of the neurological sciences 09/2014; · 2.32 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BackgroundBICAMS (Brief International Cognitive Assessment for Multiple Sclerosis) has been recently developed as brief, practical and universal assessment tool for cognitive impairment in MS subjects. It includes the Symbol Digit Modalities Test (SDMT), the California Verbal Learning Test-2 (CVLT2) and the Brief Visuospatial Memory Test¿Revised (BVMT-R) . In this study we aimed at gathering regression based normative data for the BICAMS battery in the Italian population.Methodshealthy subjects were consecutively recruited among patient friends and relatives. Corrections for demographics were calculated using multivariable linear regression models. Test-retest reliability was assessed using the Pearson correlation coefficient.ResultsThe BICAMS battery was administered to 273 healthy subjects (180 women, mean age 38.9¿±¿13.0 years, mean education 14.9¿±¿3.0 years). Test-retest reliability was good for all the tests.Conclusions
The study provided normative data of the BICAMS for the Italian population confirming good test-retest reliability which can facilitate the use of the battery in clinical practice, also for longitudinal patient assessments.
[Show abstract][Hide abstract] ABSTRACT: The assessment of gait abnormalities in individuals with Multiple Sclerosis (MS) represents a key factor in evaluating the effectiveness of rehabilitation treatments. Despite the availability of sophisticated equipment to objectively evaluate the kinematic aspects of gait, there are still some difficulties in processing the large and complex amount of data they produce in the daily clinical routine. On the basis of the above-mentioned considerations we propose a novel characterization of gait kinematics in individuals with MS, based on a single measure (Gait Profile Score, GPS) obtained from a quantitative three-dimensional analysis of gait performed using an opto-electronic system. We also investigated the correlation between GPS and the Expanded Disability Status Scale (EDSS) values. Thirty-four patients suffering from relapsing-remitting MS (13 female, 21 male, mean age 46.7 years) with an EDSS score of ≤ 6 underwent a gait analysis from which the GPS index was calculated. Their results were compared with those of a control group of healthy age- and gender-matched subjects. The GPS of individuals with MS was found significantly higher with respect to controls (9.12° vs. 5.67°, p < 0.001) as the result of kinematic differences in gait patterns referring to pelvic tilt and rotation, hip flexion-extension and rotation, knee flexion-extension and ankle dorsi- and plantar-flexion. A moderate correlation was also found between the EDSS score of the participants and their GPS values (r = 0.63, p < 0.001). The GPS index thus appears suitable to represent gait deviations from physiological patterns in individuals affected by MS and potentially useful in assessing the outcomes related both to rehabilitation programs and pharmacologic/physical therapies.
Journal of the Neurological Sciences 07/2014; · 2.24 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Conserved populations, such as Sardinians, displaying elevated rates of familial or sporadic amyotrophic lateral sclerosis (ALS) provide unique information on the genetics of the disease. Our aim was to describe the genetic profile of a consecutive series of ALS patients of Sardinian ancestry. All ALS patients of Sardinian ancestry, identified between 2008 and 2013 through the Italian ALS Genetic Consortium, were eligible to be included in the study. Patients and controls underwent the analysis of TARDBP, C9ORF72, SOD1, and FUS genes. Genetic mutations were identified in 155 out of 375 Sardinian ALS cases (41.3%), more commonly the p.A382T and p.G295S mutations of TARDBP and the GGGGCC hexanucleotide repeat expansion of C9ORF72. One patient had both p.G295S and p.A382T mutations of TARDBP and 8 carried both the heterozygous p.A382T mutation of TARDBP and a repeat expansion of C9ORF72. Patients carrying the p.A382T and the p.G295S mutations of TARDBP and the C9ORF72 repeat expansion shared distinct haplotypes across these loci. Patients with cooccurrence of C9ORF72 and TARDBP p.A382T missense mutation had a significantly lower age at onset and shorter survival. More than 40% of all cases on the island of Sardinia carry a mutation of an ALS-related gene, representing the highest percentage of ALS cases genetically explained outside of Scandinavia. Clinical phenotypes associated with different genetic mutations show some distinctive characteristics, but the heterogeneity between and among families carrying the same mutations implies that ALS manifestation is influenced by other genetic and nongenetic factors.
[Show abstract][Hide abstract] ABSTRACT: Most of Multiple Sclerosis (MS) patients undergo disease modifying drug (DMD) therapy at childbearing age. The objective of this prospective, collaborative study, was to assess outcomes of pregnancies fathered by MS patients undergoing DMD.
[Show abstract][Hide abstract] ABSTRACT: Multiple sclerosis (MS) is an autoimmune disease of the central nervous system that has a notably high incidence in Sardinia. Our study focuses on two HLA class II haplotypes associated with the disease in Sardinia, the rare predisposing DRB1*15:01-DQB1*06:02 and the widespread protective DRB1*16:01-DQB1*05:02. This framework enabled the highlighting of HLA binding pocket specificity and peptide recognition mechanisms by employing molecular dynamics simulations of the whole DRB1-DQB1 haplotype interacting with MBP- and EBV-derived peptides. We analyzed peptide-protein interaction networks and temporal evolution of the original complexes and after key amino acid mutations. The mutation G86V of the protective DRB1 allele exerted its effect mainly in the presence of the EBV viral peptide, with local and long range outcomes. However, the V38A mutation of the protective DQB1 showed a long range effect only in the case of the MBP myelin peptide. Our findings also demonstrate a DRB1/DQB1 complementary molecular recognition of peptides. This mechanism could provide a robust synergistic action and a differential role of DRB1 and DQB1 in tissues and in the time-steps towards autoimmunity. In addition, we demonstrate that negatively charged residues in pockets 4 and 9 play a role in MS susceptibility. Our findings are supported by recent experiments using a closely related MS animal model. Overall, our analysis confirms the role of the DRB1-DQB1 haplotype in conferring disease predisposition and could provide a valuable aid in designing optimal therapeutic peptides for MS therapy.
[Show abstract][Hide abstract] ABSTRACT: Mitoxantrone is an immunosuppressive drug approved for aggressive relapsing and progressive multiple sclerosis. In recent years, its use has decreased due to the risk of severe adverse events and the introduction of novel therapies, such as natalizumab or fingolimod. Mitoxantrone is effective in reducing inflammatory activity by decreasing the number of relapses and MRI lesions and simultaneously decreasing the worsening of disability. Apart from its role as a second/third-line therapy, some studies suggest its use as an induction therapy. However, mitoxantrone use is limited because of its potential risk of severe adverse events, such as cardiotoxicity and the induction of therapy-related acute leukemia. Genetic markers are on evaluation to predict side effects and therapeutic efficacy, which is consistent with the direction of personalized treatment. Considering its efficacy and the potential risks, mitoxantrone use is limited to active patients after a careful, individualized evaluation of the risk/benefit balance.
Expert Review of Neurotherapeutics 05/2014; · 2.96 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Epstein-Barr virus and Mycobacterium avium subsp. paratuberculosis (MAP) have been associated to multiple sclerosis (MS). We searched for antibodies against the homologous peptides Epstein-Barr virus nuclear antigen 1 (EBNA1)400-413, MAP_0106c protein (MAP)121-132, and myelin basic protein (MBP)85-98 on a MS Sardinian cohort, showing that these antibodies are highly prevalent among MS patients compared to healthy controls. Competitive assay demonstrated that antibodies recognizing EBNA1400-413 and MAP121-132 cross-react with MBP85-98, possibly through a molecular mimicry mechanism. Indeed, the fact that peptides from different pathogens can be cross-recognized by antibodies targeting self-epitopes supports the hypothesis that EBV and MAP might trigger autoimmunity through a common target.
Journal of Neuroimmunology 05/2014; · 3.03 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Neuroactive steroid family includes molecules synthesized in peripheral glands (i.e., hormonal steroids) and directly in the nervous system (i.e., neurosteroids) which are key regulators of the nervous function. As already reported in clinical and experimental studies, neurodegenerative diseases affect the levels of neuroactive steroids. However, a careful analysis comparing the levels of these molecules in cerebrospinal fluid (CSF) and in plasma of multiple sclerosis (MS) patients is still missing. To this aim, the levels of neuroactive steroids were evaluated by liquid chromatography-tandem mass spectrometry in CSF and plasma of male adults affected by Relapsing Remitting MS and compared with those collected in control patients. An increase of pregnenolone and isopregnanolone levels associated with a decrease of progesterone metabolites, dihydroprogesterone and tetrahydroprogesterone was observed in CSF of MS patients. Moreover, an increase of 5α-androstane-3α,17β-diol and of 17β-estradiol levels associated with a decrease of dihydrotestosterone also occurred. In plasma, an increase of pregnenolone, progesterone and dihydrotestosterone and a decrease of dihydroprogesterone and tetrahydroprogesterone levels were reported. The present study shows for the first time that the levels of several neuroactive steroids, and particularly those of progesterone and testosterone metabolites, are deeply affected in CSF of relapsing remitting MS male patients.This article is protected by copyright. All rights reserved.
Journal of Neurochemistry 04/2014; · 3.97 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Epstein–Barr virus and Mycobacterial avium ss. paratuberculosis (MAP) have been associated to Multiple Sclerosis (MS). We searched for antibodies against the homologous peptides Epstein Barr Virus Nuclear Antigen 1 (EBNA1)400-413, MAP_0106c protein (MAP)121-132, and Myelin Basic Protein (MBP)85–98 on a MS Sardinian cohort, showing that these antibodies are highly prevalent among MS patients compared to healthy controls. Competitive assay demonstrated that antibodies recognizing EBNA1400-413 and MAP121-132 cross-react with MBP85–98, possibly through a molecular mimicry mechanism. Indeed, the fact that peptides from different pathogens can be cross-recognized by antibodies targeting self-epitopes, support the hypothesis that EBV and MAP might trigger autoimmunity trough a common target.
Journal of neuroimmunology 01/2014; · 2.84 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Multiple Sclerosis (MS) is an autoimmune disease of the central nervous system that has a notably high incidence in Sardinia. Our study focuses on two HLA class II haplotypes associated with the disease in Sardinia, the rare predisposing DRB1*15:01-DQB1*06:02 and the widespread protective DRB1*16:01-DQB1*05:02. This framework enabled the highlighting of HLA binding pocket specificity and peptide recognition mechanisms, by employing molecular dynamics simulations of the whole DRB1-DQB1 haplotype interacting with MBP- and EBV-derived peptides. We analyzed peptide-protein interaction networks and temporal evolution of the original complexes and after key amino acid mutations. The mutation G86V of the protective DRB1 allele exerted its effect mainly in presence of the EBV viral peptide, with local and long range outcomes. However, the V38A mutation of the protective DQB1 showed a long range effect only in the case of the MBP myelin peptide. Our findings demonstrate also a DRB1/DQB1 complementary molecular