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Background and purpose: Genetic generalized epilepsies (GGEs) encompass a group of syndromes of mainly genetic causes, characterized by the involvement of both hemispheres. MicroRNAs (miRNAs) are small non‐coding RNAs with a critical role in the regulation of neuronal biological processes through gene expression modulation. Dysregulated miRNA expression has been shown in epilepsy. Due to their stability in biological fluids like serum, miRNAs have assumed a prominent role in biomarker research. Our aim was to evaluate circulating levels of three miRNAs in GGE patients and assess their putative diagnostic value. Methods: MiR‐146a, miR‐155 and miR‐132 were quantified by real‐time polymerase chain reaction in the serum of 79 GGE patients (47 women, 32 men, 35.1 ± 12.4 years) and 67 healthy individuals (41 women, 26 men, 42.4 ± 10.1 years). Relative expression values were calculated using the 2–ΔΔCt method. Receiver operating characteristic curve analysis was performed to assess diagnostic value. MiRNA expression was correlated with clinicopathological features. Results: Serum levels of miR‐146a and miR‐155 were significantly upregulated in GGE patients relative to controls (3.13 and 6.05, respectively). Combined miR‐146a, miR‐155 and miR‐132 serum levels performed well as a diagnostic biomarker, discriminating GGE patients from controls with an area under the curve of 0.85, 80% specificity and 73% sensitivity. Conclusions: Our results indicate that miR‐146a, miR‐155 and miR‐132 may partake in GGE epileptogenesis. A panel of three circulating miRNAs with potential value as a GGE biomarker is reported for the first time. Novel biomarkers may help to identify new treatment targets and contribute to improved patients' quality of life through earlier diagnosis and a more precise prognosis. [ABSTRACT FROM AUTHOR]

Introduction: Neuromyelitis optica spectrum disorders (NMOSD) and MOG-associated disease (MOGAD) are an increasingly recognized group of demyelinating disorders of the central nervous system. Previous studies suggest that prognosis is predicted by older age at onset, number of relapses, the severity of the first attack and autoantibody status., Objective: To study prognostic factors associated with disability progression and additional relapses in the 3-year follow-up of a national NMOSD/MOGAD cohort., Results: Out of 180 of the initial Portuguese cohort, data on 82 patients was available at the end of the follow-up period (2019-2022). Two patients died. Twenty (24.4%) patients had one or more attack in this period (25 attacks in total), mostly transverse myelitis (TM) (56.0%) or optic neuritis (32.0%). MOGAD was significantly associated with a monophasic disease course (p = 0.03), with milder attacks (p = 0.01), while AQP4 + NMOSD was associated with relapses (p = 0.03). The most common treatment modalities were azathioprine (38.8%) and rituximab (18.8%). AQP4 + NMOSD more frequently required chronic immunosuppressive treatment, particularly rituximab (p = 0.01). Eighteen (22.5%) had an EDSS ≥6 at the end of the follow-up. AQP4 + NMOSD (p < 0.01) and the occurrence of transverse myelitis (TM) during disease (p = 0.04) correlated with an EDSS≥6 at the end of the follow-up period. MOGAD was significantly associated with an EDSS<6 (p < 0.01), and MOG+ cases that reached an EDSS>6 were significantly older (64.0 ± 2.8 versus 31.0 ± 17.1, p = 0.017). A bivariate logistic regression model including the serostatus and TM attacks during disease history successfully predicted 72.2% of patients that progressed to an EDSS≥6., Conclusion: This study highlights that myelitis predict increased disability (EDSS≥6) in NMOSD/MOGAG and AQP4 positivity is associated with increased disability., Competing Interests: Declaration of competing interest Authors declare no conflict of interest regarding this work., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Disease modifying therapies (DMTs) used for treating people with relapsing-remitting multiple sclerosis (pwRRMS) target the immune system by different mechanisms of action. However, there is a lack of a comprehensive assessment of their effects on the immune system in comparison to treatment-naïve pwRRMS. Herein, we evaluated the numbers of circulating B cells, CD4 + and CD8 + T cells, regulatory T cells (Tregs), natural killer (NK) cells and NKT cells, and their subsets, in pwRRMS who were treatment-naïve or treated with different DMTs. Compared to treatment-naïve pwRRMS, common and divergent effects on immune system cells were observed on pwRRMS treated with different DMTs, with no consistent pattern across all therapies in any of the cell populations analysed. PwRRMS treated with fingolimod, dimethyl fumarate (DMF), or alemtuzumab have reduced numbers of CD4 + and CD8 + T cells, as well as Treg subsets, with fingolimod causing the most pronounced decrease in T cell subsets. In contrast, teriflunomide and interferon (IFN) β have minimal impact on T cells, and natalizumab marginally increases the number of memory T cells in the blood. The effect of DMTs on the B cell, NKT and NK cell subsets is highly variable with alemtuzumab inducing a strong increase in the number of the most immature NK cells and its subsets. This study comprehensively evaluates the magnitude of the effect of different DMTs on blood immune cells providing a better understanding of therapy outcome. Furthermore, the lack of a discernible pattern in the effects of DMTs on blood immune cells suggests that multiple immune cells can independently modulate the disease., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: A possible genetic contribution of dopamine D3 receptor (DRD3) to cognitive impairment in Parkinson's disease (PD) has yet to be investigated., Objective: To explore the effects of rs6280 (Ser9Gly) genotype on PD patients' cognitive performance and to clarify possible interactions with psychopathology., Methods: Two hundred and fifty-three consecutive PD patients underwent neurological and neuropsychological evaluations, which included: Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn & Yahr scale (H&Y), Dementia Rating Scale-2 (DRS-2), and Hospital Anxiety and Depression Scale (HADS). rs6280 polymorphism was genotyped for all PD patients and for 270 ethnically matched healthy volunteers (HC). Non-parametric group comparisons and logistic regressions were used for data analyses., Results: rs6280 genotype did not differ between PD and HC groups. PD patients with rs6280 CC genotype had more impaired cognitive performance (i.e., <1st percentile of demographically adjusted norms) on DRS-2 subscales Initiation/Perseveration and Construction than those with TT genotype. These associations remained statistically significant when other covariates (e.g., demographic features, disease duration, severity of motor symptoms in OFF and ON states, anti-parkinsonian medication, and psychopathology symptoms) were taken into consideration. PD patients with rs6280 TC had less anxiety (i.e., HADS Anxiety≥11) than those with TT (p = 0.012). This association was also independent of other covariates., Conclusions: Study findings suggest that rs6280 CC genotype predisposes to executive dysfunction and visuoconstructional deficits, whereas the heterozygous genotype protects from anxiety in PD. These effects do not appear to be dependent of one another. rs6280 is not a genotypic susceptibility factor for PD.

The importance of circulating immune cells to primary progressive multiple sclerosis (PPMS) pathophysiology is still controversial because most immunotherapies were shown to be ineffective in treating people with PPMS (pwPPMS). Yet, although controversial, data exist describing peripheral immune system alterations in pwPPMS. This study aims to investigate which alterations might be present in pwPPMS free of disease-modifying drugs (DMD) in comparison to age- and sex-matched healthy controls. A multicentric cross-sectional study was performed using 23 pwPPMS and 23 healthy controls. The phenotype of conventional CD4 + and CD8 + T cells, regulatory T cells (Tregs), B cells, natural killer (NK) T cells and NK cells was assessed. Lower numbers of central memory CD4 + and CD8 + T cells and activated HLA-DR + Tregs were observed in pwPPMS. Regarding NK and NKT cells, pwPPMS presented higher percentages of CD56 dim CD57 + NK cells expressing NKp46 and of NKT cells expressing KIR2DL2/3 and NKp30. Higher disease severity scores and an increasing time since diagnosis was correlated with lower numbers of inhibitory NK cells subsets. Our findings contribute to reinforcing the hypotheses that alterations in peripheral immune cells are present in pwPPMS and that changes in NK cell populations are the strongest correlate of disease severity.

Introduction: Several neuroimmunological disorders have distinct phenotypes according to the age of onset, as in multiple sclerosis or myasthenia gravis. It is also described that late onset NMOSD (LONMOSD) has a different phenotype., Objective: To describe the clinical/demographic characteristics of the LONMOSD and distinguish them from those with early onset (EONMOSD)., Methods: From a nationwide Portuguese NMOSD study we analyzed the clinical/demographic characteristics of the LONMOSD., Results: From the 180 Portuguese patients 45 had disease onset after 50 years old, 80% were female. 23 had anti-AQP4 antibodies (51.1%), 13 anti-MOG antibodies (28.9%) and 9 were double seronegative (20.0%). The most common presenting phenotypes in LONMOSD were transverse myelitis (53.3%) and optic neuritis (26.7%), without difference from EONMOSD (p = 0.074). The mean EDSS for LONMOSD was 6.0 (SD=2.8), after a mean follow-up time of 4.58 (SD=4.47) years, which was significantly greater than the mean EDSS of EONMOSD (3.25, SD=1.80)(p = 0.022). Anti-AQP4 antibodies positive LONMOSD patients had increased disability compared to anti-MOG antibodies positive LONMOSD (p = 0.022). The survival analysis showed a reduced time to use a cane for LONMOSD, irrespective of serostatus (p<0.001)., Conclusions: LONMOSD has increased disability and faster progression, despite no differences in the presenting clinical phenotype were seen in our cohort., (Copyright © 2022. Published by Elsevier B.V.)

Introduction: The impact of COVID-19 in patients with neuroimmunological disorders is not fully established. There is some evidence suggesting an increased risk of more severe infection associated with the use of immunosuppressors in this population., Objective: To characterize SARS-CoV-2 infection in patients followed in the neuroimmunology outpatient clinic of a tertiary centre from the north of Portugal., Methods: Retrospective analysis of neuroimmunological patients with PCR-proven SARS-CoV-2 infection during the observational period of 20 months., Results: Ninety-one patients were infected, 68.1% female, with a mean age of 48.9±16.7 years. The median disease duration was 11.0 (IQR 6.0-19.0) years. Sixty-one patients (67.0%) had Multiple Sclerosis, of which 50 with relapsing-remitting course, 12 (13.2%) Myasthenia Gravis (MG), 6 (6.6%) Autoimmune Encephalitis and 6 (6.6%) Chronic Inflammatory Demyelinating Polyneuropathy. Seventy-six patients (83.5%) were taking disease-modifying therapy, 77.6% of which were on immunosuppressants, including anti-CD20 in 12 (13.2%). Most patients had mild COVID-19 (84.6%), with 3 cases (3.3%) of severe disease and, 7 cases (7.7%) of critical disease being reported. In total, 13 patients were hospitalized and 4 died. Patients with severe to critical disease were significantly older than patients with milder forms (69.4±21.0 versus 46.5±14.4 years, p<0.01). MG was also associated with more severe disease (p=0.02). There was no association between comorbidities or use of immunosuppressors (including anti-CD20) and COVID-19 severity., Conclusions: Greater age and MG were associated with severe or critical COVID-19. We found no association between a specific DMT, including anti-CD20, and outcome. Clinical recovery was achieved by 93.4%., (Copyright © 2022. Published by Elsevier B.V.)

Objective: The aim of this study is to assess the peripheral immune system of newly diagnosed patients with relapsing remitting multiple sclerosis (RRMS) and compare it to healthy controls (HC)., Methods: This cross-sectional study involves 30 treatment-naïve newly diagnosed patients with RRMS and 33 sex- and age-matched HC. Peripheral blood mononuclear cells were analyzed regarding: i) thymic function surrogates [T cell receptor excision circles (TRECs) and recent thymic emigrants (RTEs)]; ii) naïve and memory CD4 + and CD8 + T cells subsets; iii) T helper (Th) phenotype and chemokine receptors expression on CD8 + T cells subsets; iv) regulatory T cell (Tregs) phenotype; and exclude expression of activating/inhibitory receptors by natural killer (NK) and NKT cells. Analyses were controlled for age, sex, and human cytomegalovirus (HCMV) IgG seroprevalence., Results: Newly diagnosed patients with RRMS and HC have equivalent thymic function as determined by similar numbers of RTEs and levels of sjTRECs, DJβTRECs, and sj/DJβTREC ratio. In the CD8 + T cells compartment, patients with RRMS have a higher naive to memory ratio and lower memory cell counts in blood, specifically of effector memory and TemRA CD8 + T cells. Interestingly, higher numbers and percentages of central memory CD8 + T cells are associated with increasing time from the relapse. Among CD4 + T cells, lower blood counts of effector memory cells are found in patients upon controlling for sex, age, and anti-HCMV IgG seroprevalence. Higher numbers of CD4 + T cells (both naïve and memory) and of Th2 cells are associated with increasing time from the relapse; lower numbers of Th17 cells are associated with higher MS severity scores (MSSS). Patients with RRMS have a higher percentage of naïve Tregs compared with HC, and lower percentages of these cells are associated with higher MSSS. Percentages of immature CD56 bright NK cells expressing the inhibitory receptor KLRG1 and of mature CD56 dim CD57 + NK cells expressing NKp30 are higher in patients. No major alterations are observed on NKT cells., Conclusion: Characterization of the peripheral immune system of treatment-naïve newly diagnosed patients with RRMS unveiled immune features present at clinical onset including lower memory T cells blood counts, particularly among CD8 + T cells, higher percentage of naïve Tregs and altered percentages of NK cells subsets expressing inhibitory or activating receptors. These findings might set the basis to better understand disease pathogenesis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Canto-Gomes, Silva, Rb-Silva, Boleixa, da Silva, Cheynier, Costa, González-Suárez, Correia-Neves, Cerqueira and Nobrega.)

Introduction: Neuromyelitis optica spectrum disorder (NMOSD) is a rare disorder in which astrocyte damage and/or demyelination often cause severe neurological deficits., Objective: To identify Portuguese patients with NMOSD and assess their epidemiological/clinical characteristics., Methods: This was a nationwide multicenter study. Twenty-four Portuguese adult and 3 neuropediatric centers following NMOSD patients were included., Results: A total of 180 patients met the 2015 Wingerchuk NMOSD criteria, 77 were AQP4-antibody positive (Abs+), 67 MOG-Abs+, and 36 seronegative. Point prevalence on December 31, 2018 was 1.71/100,000 for NMOSD, 0.71/100,000 for AQP4-Abs+, 0.65/100,000 for MOG-Abs+, and 0.35/100,000 for seronegative NMOSD. A total of 44 new NMOSD cases were identified during the two-year study period (11 AQP4-Abs+, 27 MOG-Abs+, and 6 seronegative). The annual incidence rate in that period was 0.21/100,000 person-years for NMOSD, 0.05/100,000 for AQP4-Abs+, 0.13/100,000 for MOG-Abs+, and 0.03/100,000 for seronegative NMOSD. AQP4-Abs+ predominated in females and was associated with autoimmune disorders. Frequently presented with myelitis. Area postrema syndrome was exclusive of this subtype, and associated with higher morbidity/mortality than other forms of NMOSD. MOG-Ab+ more often presented with optic neuritis, required less immunosuppression, and had better outcome., Conclusion: Epidemiological/clinical NMOSD profiles in the Portuguese population are similar to other European countries., (Copyright © 2021. Published by Elsevier B.V.)

Increasing evidence has shown that individuals with Multiple Sclerosis (MS) have lower 25-hydroxyvitamin D [25(OH)D] levels compared to healthy controls. There is no information regarding 25(OH)D levels and MS in Portugal. Therefore the aim of the current study was to examine the levels of 25(OH)D in a group of patients with MS and in healthy matched controls, as well as the association of 25(OH)D levels with disease course, disability and severity. A group of 244 unrelated Portuguese patients, with a definitive diagnosis of MS, and 198 ethnically matched healthy controls were included in the study. A sub-group of patients with recent disease onset was included. Serum 25(OH)D was measured using an electrochemiluminescence binding assay. The mean serum level of 25(OH)D in patients with MS was 39.9±22.0 nmol/L, which was significantly lower (p<0.0001) than those in healthy controls, 55.4±23.4 nmol/L. There was a negative correlation between 25(OH)D levels and EDSS (r=-0.293, p<0.0001) and MSSS scores (r=-0.293, p<0.0001). In multiple logistic regression analysis adjusted for age, gender, disease form, EDSS, disease duration and MSSS, 25(OH)D levels were independently associated with EDSS (p=0.004) and disease duration (p=0.016), and with MSSS (p=0.001). In accordance with the majority of the literature, low serum 25(OH)D levels were associated with susceptibility and disability in MS patients from Portugal. Lower serum 25(OH)D levels were also found in patients with a recent disease onset, supporting vitamin D levels as a risk factor for MS., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Purpose: Neuroinflammation appears as an important epileptogenic mechanism. Experimental and clinical studies have demonstrated an upregulation of pro-inflammatory cytokines such as IL-1β and TNF-α, in mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). Expression of these cytokines can be modulated by polymorphisms such as rs16944 and rs1800629, respectively, both of which have been associated with febrile seizures (FS) and MTLE-HS development. The human leukocyte antigen (HLA) system has also been implicated in diverse epileptic entities, suggesting a variable role of this system in epilepsy. Our aim was to analyse the association between immunogenetic factors and MTLE-HS development. For that rs16944 (-511 T>C, IL-1β), rs1800629 (-308 G>A, TNF-α) polymorphisms and HLA-DRB1 locus were genotyped in a Portuguese Population., Methods: We studied 196 MTLE-HS patients (108 females, 88 males, 44.7 ± 12.0 years, age of onset = 13.6 ± 10.3 years, 104 with FS antecedents) and 282 healthy controls in a case-control study., Results: The frequency of rs16944 TT genotype was higher in MTLE-HS patients compared to controls (14.9% in MTLE-HS vs. 7.7% in controls, p = 0.021, OR [95% CI] = 2.20 [1.13-4.30]). This association was independent of FS antecedents. No association was observed between rs1800629 genotypes or HLA-DRB1 alleles and MTLE-HS susceptibility. Also, no correlation was observed between the studied polymorphisms and disease age of onset., Conclusion: The rs16944 TT genotype is associated with MTLE-HS development what may be explained by the higher IL-1β levels produced by this genotype. High IL-1β levels may have neurotoxic effects or imbalance neurotransmission leading to seizures.

Vitamin D status in human populations has become a matter of great concern, in the wake of a multitude of published works that document widespread vitamin D deficiency across Europe, even in countries with abundant sunlight. In Portugal there are no measures of 25-hydroxyvitamin D - 25(OH)D - levels in the general adult population. The purpose of this study was to measure 25(OH)D levels in a healthy population cohort and investigate the possible association with season and selected demographic and laboratory measurements. A cohort of 198 participants (18-67 years) living in the north of Portugal, Porto, conducted in July and August 2015 (summer time) and April 2016 (winter time) was studied to evaluate serum 25(OH)D levels. Sociodemographic characteristics (age, sex and body mass index) and season of the year were taken into account as possible 25(OH)D levels codeterminants. In the whole group, the mean level of serum 25(OH)D was 55.4±23.4 nmol/L, with 48% of the population presenting levels compatible with vitamin D deficiency (below 50 nmol/L). In the winter period, this value reaches 74%. No statistically significant differences were observed between genders (57.4±23.9 vs. 53.3±22.8 nmol/L, p=0.219) as well as no statistically significant correlation was found between age and 25(OH)D levels (p=0.349). As expected higher levels of 25(OH)D were observed in summer than in winter (68.2±21.5 vs. 42.2±16.9 nmol/L; p<0.0001). Serum 25(OH)D levels were significantly lower in obese compared to non-obese subjects (46.6±17.6 vs. 57.7±24.2 nmol/L, p=0.012). Vitamin D deficiency is prevalent in this area, affecting almost half of the population. Body mass index and season are predictors for lower 25-hydroxyvitamin D levels and vitamin D status. An effective strategy to prevent vitamin D deficiency and insufficiency should be envisaged and implemented in our population., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: The cause of Multiple Sclerosis (MS) remains poorly understood, but it is widely believed to be an autoimmune disease occurring in genetically susceptible individuals after exposure to as-yet undefined environmental factors. One of these environmental factors is vitamin D, a well-known immune modulator. The biologically active form of vitamin D, 1,25-dihydroxyvitamin D3, has been shown to exert its immune modulatory properties through its nuclear receptor (VDR) namely by inhibiting the proliferation of Th cells. The purpose of this study was to evaluate the influence of FokI VDR polymorphism in MS development and progression., Methods: A group of 533 unrelated Portuguese patients with a definitive diagnosis of MS and 446 ethnically matched healthy controls were included in the study. FokI was genotyped using a PCR-based TaqMan Genotyping Assay and serum 25-hydroxyvitamin D [25(OH)D] was also assessed., Results: A statistically significant higher frequency of the ff genotype was observed in MS patients (15.6% vs. 10.1%, p=0.012, OR (95% CI)=1.687(1.120-2.541)). No differences were observed in the frequencies of the FokI polymorphism according to disease course or with progression of disability. None of the genotypes was significantly associated with 25(OH)D serum levels., Conclusions: An association between FokI ff genotype and MS susceptibility was found, but not with disease form or progression. Additional clinical and experimental studies should take the FokI VDR polymorphism into account, and further clarify the role of vitamin D, its metabolites and its receptor in MS., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The aetiology of MG is unknown, but both genetic and environmental factors are important. Over the years association of MG with Human Leucocyte Antigens (HLA) has been described in different populations. We investigated a possible association between HLA-DRB1 alleles and age of onset in MG. One hundred and fourteen MG patients (82 females) and 282 control individuals (CP) were studied. Patients were classified according to the age of onset (early-onset <50, n = 74 and late-onset ≥ 50, n = 20). Patients with thymoma (n = 20) were analyzed separately. HLA-DRB1 and HLA-B*08 genotyping was performed using PCR-SSP methodology. HLA-DRB1*03 allele was overrepresented in the global MG. When the early-onset subgroup was considered, this association became even stronger. Regarding the late-onset subgroup, the frequency of HLA-DRB1*01 allele was higher than in the CP. For the thymoma subgroup, the HLA-DRB1*10 allele frequency was significantly higher when compared to the CP. These results have shown a strong association of HLA-DRB1*03 with MG, especially for EOMG also in our population. HLA-DRB1*01 was associated to LOMG suggesting that is a susceptibility factor for this subgroup of the disease. This study confirms a different genetic background of MG subgroups regarding age of onset., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with multi-organ inflammation, linked to loss of immune tolerance to self-antigens and the production of a diversity of autoantibodies, with a negative impact on the patients' quality of life. Regulatory T cells have been reported as deficient in number and function in SLE patients. However, some authors also described an enrichment of this cell type. The hypothesis that certain forms of autoimmunity may result from a conversion of Treg cells into a Th17 cell phenotype has been suggested by some studies. In fact, in SLE patients' sera, the IL-17 levels were observed as abnormally high when compared with healthy individuals. Environmental factors, such as vitamin D, that is considered a potential anti-inflammatory agent, combined with genetic and hormonal characteristics have been associated with SLE phenotype and with disease progression. The aim of this study was to evaluate the effect of vitamin D supplementation on FoxP3 expression and IL-17A-producing T cells, through FoxP3 + /IL-17A ratio. Additionally, disease evolution, serum vitamin D levels, serum autoantibodies levels and calcium metabolism (to assure safety) were also studied. We assessed 24 phenotypically well-characterized SLE patients. All patients were screened before vitamin D supplementation and 3 and 6 months after the beginning of this treatment. Peripheral blood lymphocyte's subsets were analysed by flow cytometry. Serum 25(OH)D levels significantly increased under vitamin D supplementation (p = 0.001). The FoxP3 + /IL-17A ratio in SLE patients after 6 months of vitamin D supplementation was higher than that in the baseline (p < 0.001). In conclusion, this study demonstrated that vitamin D supplementation provided favourable, immunological and clinical impact on SLE.