Gender and sex hormones in multiple sclerosis pathology and therapy

What an adult multiple sclerosis registry can tell us about pediatric onset multiple sclerosis?

BACKGROUND

Multiple Sclerosis (MS) is an immune-mediated, chronic disease of the central nervous system that affects mainly adults. However, it is increasingly recognized that MS may start in childhood resulting in a relentlessly progressive disability and cognitive impairment. Registries across the globe are reporting inconstant data about their Pediatric-Onset Multiple Sclerosis (POMS) patients. Moreover, newer lines of treatments are emerging and showing efficacy in controlling the MS disease regardless of the onset. Therefore, there is a requirement for more research into the clinical profile of POMS in different populations and ethnicities.

METHODS

This study was a cross-sectional study that included MS patients who visited the MS unit at Alexandria University from January 2019 to January 2021. We analyzed their epidemiological, clinical, radiological data, and cerebrospinal fluid (CSF) results from their updated records as well as follow-up interviews.

RESULTS

Annual Relapse Rate (ARR) was marginally less in POMS than AOMS (0.72 ± 0.57 vs 1.04 ± 0.78 relapse/year, P =.008). POMS patients had a bigger gap to their first relapse (40.0 ± 47.35 vs 22.71 ± 34.33 months, p= .066). The difference in relapse rate between the two groups was abolished after the exclusion of patients who had a gap of more than 5 years to their first relapse. AOMS patients were significantly more likely to start with a second-line disease-modifying treatment (DMT) than POMS patients (11.5% vs 31%, p= .04), whereas POMS patients were more likely to be escalated to the second line (34.6% vs 19.3%, p= .07). ARR had a positive and significant correlation with expanded disability status scale (EDSS) progression per year (rs(24)= .57 p=.003). A Mann-Whitney test indicated that POMS patients who had infratentorial involvement in the initial MRI brain had higher EDSS (3.08 ± 1.99) than POMS who did not (1.07 ± 0.79) U=24 P =.013. IgG index had a significant and positive correlation with annual EDSS progression rate rs (8) = 0.8 p=.001.

CONCLUSION

Early disease onset does not mean a higher relapse rate when including the full spectrum of POMS and longer follow-up duration. POMS patients relapsed more on the first-line DMT and escalation should be considered early. Infratentorial involvement in the initial magnetic resonance imaging (MRI) brain and high IgG index are potential predictors for aggressive disease course in POMS.

The impact of menopause on multiple sclerosis

Menopause, defined as the permanent cessation of ovarian function, represents a period of significant fluctuation in sex hormone concentrations. Sex hormones including oestrogen, progesterone, testosterone and anti-Mullerian hormone are thought have neuroinflammatory effects and are implicated in both neuroprotection and neurodegeneration. Sex hormones are thought to have a role in modifying clinical trajectory in multiple sclerosis (MS) throughout the lifespan. Multiple sclerosis predominantly effects women and is typically diagnosed early in a woman's reproductive life. Most women with MS will undergo menopause. Despite this, the effect of menopause on MS disease course remains unclear. This review examines the relationship between sex hormones and MS disease activity and clinical course, particularly around the time of menopause. It will consider the role of interventions such as exogenous hormone replacement therapy in modulating clinical outcomes in this period. Understanding the impact of menopause on multiple sclerosis is fundamental for delivering optimal care to women with MS as they age and will inform treatment decisions with the aim of minimising relapses, disease accrual and improving quality of life.

Microchimerism in multiple sclerosis: The association between sex of offspring and MRI features in women with multiple sclerosis

Aims

During pregnancy, fetal cells can migrate to the mother via blood circulation. A percentage of these cells survive in maternal tissues for decades generating a population of fetal microchimeric cells (fMCs), whose biological role is unclear. The aim of this study was to investigate the association between the sex of offspring, an indirect marker of fMCs, and magnetic resonance imaging (MRI) features in women with multiple sclerosis (MS).

Methods

We recruited 26 nulliparous MS patients (NPp), 20 patients with at least one male son (XYp), and 8 patients with only daughters (XXp). Each patient underwent brain MR scan to acquire 3D-T2w FLAIR FatSat and 3D-T1w FSPGR/TFE. Lesion Segmentation Tool (LST) and FreeSurfer were used to obtain quantitative data from MRI. Additional data were collected using medical records. Multiple regression models were applied to evaluate the association between sex of offspring and MS data.

Results

Comparing NPp and XXp, we found that NPp had larger 4th ventricle volume (2.02 ± 0.59 vs. 1.70 ± 0.41; p = 0.022), smaller left entorhinal volume (0.55 ± 0.17 vs. 0.68 ± 0.25; p = 0.028), and lower thickness in the following cortical areas: left paracentral (2.34 ± 0.16 vs. 2.39 ± 0.17; p = 0.043), left precuneus (2.27 ± 0.11 vs. 2.34 ± 0.16; p = 0.046), right lateral occipital (2.14 ± 0.11 vs. 2.25 ± 0.08; p = 0.006). NPp also had lower thickness in left paracentral cortex (2.34 ± 0.16 vs. 2.46 ± 0.17; p = 0.004), left precalcarine cortex (1.64 ± 0.14 vs. 1.72 ± 0.12; p = 0.041), and right paracentral cortex (2.34 ± 0.17 vs. 2.42 ± 0.14; p = 0.015) when compared to XYp. Comparing XYp and XXp, we found that XYp had higher thickness in left cuneus (1.80 ± 0.14 vs. 1.93 ± 0.10; p = 0.042) and left pericalcarine areas (1.59 ± 0.19 vs. 1.72 ± 0.12; p = 0.032) and lower thickness in right lateral occipital cortex (2.25 ± 0.08 vs. 2.18 ± 0.13; p = 0.027).

Discussion

Our findings suggested an association between the sex of offspring and brain atrophy. Considering the sex of offspring as an indirect marker of fMCs, we speculated that fMCs could accumulate in different brain areas modulating MS neuropathological processes.

Sex bias in lymphocytes: Implications for autoimmune diseases

Autoimmune diseases are characterized by a significant sex dimorphism, with women showing increased susceptibility to disease. This is, at least in part, due to sex-dependent differences in the immune system that are influenced by the complex interplay between sex hormones and sex chromosomes, with contribution from sociological factors, diet and gut microbiota. Sex differences are evident in the number and function of lymphocyte populations. Women mount a stronger pro-inflammatory response than males, with increased lymphocyte proliferation, activation and pro-inflammatory cytokine production, whereas men display expanded regulatory cell subsets. Ageing alters the immune landscape of men and women in differing ways, resulting in changes in autoimmune disease susceptibility. Here we review the current literature on sex differences in lymphocyte function, the factors that influence this, and the implications for autoimmune disease. We propose that improved understanding of sex bias in lymphocyte function can provide sex-specific tailoring of treatment strategies for better management of autoimmune diseases.

Biological determinants impact the neurovascular toxicity of nicotine and tobacco smoke: A pharmacokinetic and pharmacodynamics perspective

Accumulating evidence suggests that the detrimental effect of nicotine and tobacco smoke on the central nervous system (CNS) is caused by the neurotoxic role of nicotine on blood-brain barrier (BBB) permeability, nicotinic acetylcholine receptor expression, and the dopaminergic system. The ultimate consequence of these nicotine associated neurotoxicities can lead to cerebrovascular dysfunction, altered behavioral outcomes (hyperactivity and cognitive dysfunction) as well as future drug abuse and addiction. The severity of these detrimental effects can be associated with several biological determinants. Sex and age are two important biological determinants which can affect the pharmacokinetics and pharmacodynamics of several systemically available substances, including nicotine. With regard to sex, the availability of gonadal hormone is impacted by the pregnancy status and menstrual cycle resulting in altered metabolism rate of nicotine. Additionally, the observed lower smoking cessation rate in females compared to males is a consequence of differential effects of sex on pharmacokinetics and pharmacodynamics of nicotine. Similarly, age-dependent alterations in the pharmacokinetics and pharmacodynamics of nicotine have also been observed. One such example is related to severe vulnerability of adolescence towards addiction and long-term behavioral changes which may continue through adulthood. Considering the possible neurotoxic effects of nicotine on the central nervous system and the deterministic role of sex as well as age on these neurotoxic effects of smoking, it has become important to consider sex and age to study nicotine induced neurotoxicity and development of treatment strategies for combating possible harmful effects of nicotine. In the future, understanding the role of sex and age on the neurotoxic actions of nicotine can facilitate the individualization and optimization of treatment(s) to mitigate nicotine induced neurotoxicity as well as smoking cessation therapy. Unfortunately, however, no such comprehensive study is available which has considered both the sex- and age-dependent neurotoxicity of nicotine, as of today. Hence, the overreaching goal of this review article is to analyze and summarize the impact of sex and age on pharmacokinetics and pharmacodynamics of nicotine and possible neurotoxic consequences associated with nicotine in order to emphasize the importance of including these biological factors for such studies.

T cell transgressions: Tales of T cell form and function in diverse disease states

Insights into T cell form, function, and dysfunction are rapidly evolving. T cells have remarkably varied effector functions including protecting the host from infection, activating cells of the innate immune system, releasing cytokines and chemokines, and heavily contributing to immunological memory. Under healthy conditions, T cells orchestrate a finely tuned attack on invading pathogens while minimizing damage to the host. The dark side of T cells is that they also exhibit autoreactivity and inflict harm to host cells, creating autoimmunity. The mechanisms of T cell autoreactivity are complex and dynamic. Emerging research is elucidating the mechanisms leading T cells to become autoreactive and how such responses cause or contribute to diverse disease states, both peripherally and within the central nervous system. This review provides foundational information on T cell development, differentiation, and functions. Key T cell subtypes, cytokines that create their effector roles, and sex differences are highlighted. Pathological T cell contributions to diverse peripheral and central disease states, arising from errors in reactivity, are highlighted, with a focus on multiple sclerosis, rheumatoid arthritis, osteoarthritis, neuropathic pain, and type 1 diabetes.

Sex-specific disruption in corticospinal excitability and hemispheric (a)symmetry in multiple sclerosis

Multiple Sclerosis (MS) is a neurodegenerative disease in which pathophysiology and symptom progression presents differently between the sexes. In a cohort of people with MS (n = 110), we used transcranial magnetic stimulation (TMS) to investigate sex differences in corticospinal excitability (CSE) and sex-specific relationships between CSE and cognitive function. Although demographics and disease characteristics did not differ between sexes, males were more likely to have cognitive impairment as measured by the Montreal Cognitive Assessment (MoCA); 53.3% compared to females at 26.3%. Greater CSE asymmetry was noted in females compared to males. Females demonstrated higher active motor thresholds and longer silent periods in the hemisphere corresponding to the weaker hand which was more typical of hand dominance patterns in healthy individuals. Males, but not females, exhibited asymmetry of nerve conduction latency (delayed MEP latency in the hemisphere corresponding to the weaker hand). In males, there was also a relationship between delayed onset of ipsilateral silent period (measured in the hemisphere corresponding to the weaker hand) and MoCA, suggestive of cross-callosal disruption. Our findings support that a sex-specific disruption in CSE exists in MS, pointing to interhemispheric disruption as a potential biomarker of cognitive impairment and target for neuromodulating therapies.

Drug and Neurofilament Levels in Serum and Breastmilk of Women With Multiple Sclerosis Exposed to Natalizumab During Pregnancy and Lactation

Objective

To determine the transfer of the monoclonal antibody natalizumab into breastmilk and to evaluate drug and serum neurofilament light chain ((s)NfL) levels in natalizumab exposed pregnancies and lactation periods.

Methods

Eleven women with relapsing remitting multiple sclerosis treated with natalizumab during pregnancy and lactation were included in this study. Breastmilk samples were collected up to 302 days after delivery and analyzed for natalizumab concentration and NfL. Additionally, maternal drug levels and sNfL were determined preconceptually, in each trimester, at delivery and postpartum. Clinical and radiological disease activity was systemically assessed across pregnancy and postpartum period.

Results

The mean average natalizumab concentration in breast milk was low at 0.06 µg/ml [standard deviation (SD) 0.05] in the eight patients who provided serial breastmilk samples with an estimated mean absolute infant dose of 0.007 mg/kg/d (SD 0.005). The relative infant dose (RID), a metric comparing the infant with maternal drug exposure was low as well with a mean of 0.04% (SD=0.03). Most patients had a maximum concentration in breast milk at one to eight days after infusion. Pregnancy was associated with a non-significant decline of the median natalizumab serum concentration. All patients exposed to natalizumab prior (n=10) and during pregnancy (n=11) kept free of disease activity during gestation. While pregnancy was associated with low sNfL levels in patients treated with natalizumab prior and during pregnancy, the postpartum period was linked to a transient sNfL increase in some patients without any evidence of clinical or radiological disease activity. NfL was detectable in the majority of breastmilk samples with a median concentration of 1.7 pg/ml (range 0.004-18.1).

Conclusion

We determined transfer of natalizumab into breastmilk with an RID far below the threshold of concern of 10%. Studies including childhood development assessment are needed in order to gain safety data about natalizumab-exposed breastfeeding. SNfL assessment might be a useful adjunct to monitor silent disease activity and therapeutic response during pregnancy and postpartum period. However, further investigations regarding transient postpartum sNfL increases are required to determine its association to parturition per se or to a silent disease activity in people with multiple sclerosis.

Cell of all trades: oligodendrocyte precursor cells in synaptic, vascular, and immune function

Oligodendrocyte precursor cells (OPCs) are not merely a transitory progenitor cell type, but rather a distinct and heterogeneous population of glia with various functions in the developing and adult central nervous system. In this review, we discuss the fate and function of OPCs in the brain beyond their contribution to myelination. OPCs are electrically sensitive, form synapses with neurons, support blood-brain barrier integrity, and mediate neuroinflammation. We explore how sex and age may influence OPC activity, and we review how OPC dysfunction may play a primary role in numerous neurological and neuropsychiatric diseases. Finally, we highlight areas of future research.

Progressive brain microstructural damage in patients with multiple sclerosis but not in patients with neuromyelitis optica spectrum disorder: A cross-sectional and follow-up tract-based spatial statistics study

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) may sometimes be misdiagnosed as multiple sclerosis (MS) because both disorders have similar clinical presentations and commonly show white matter damage in the brain. Diffusion tensor imaging (DTI) is an advanced MRI technique to assess the microstructural organization of white matter and provides greater pathological specificity than conventional MRI. In the present combined cross-sectional and longitudinal study, the novel DTI technique of Track-Based Spatial Statistics (TBSS) was used to investigate the difference of DTI parameter abnormalities between NMOSD and MS.

METHODS

A total of 42 patients with NMOSD, 51 patients with MS and 56 health controls (HC) were recruited and of these 14 patients with NMOSD and 13 patients with MS were also studied at follow-up after an average interval of approximately one year. Measurements of fractional anisotropy (FA), mean diffusion (MD), axial diffusivity (AD) and radial diffusivity (RD) were compared at baseline and follow-up in patients with NMOSD and MS.

RESULTS

Significant reduction in FA, increase in MD, AD and RD were observed in patients with MS (p < 0.05) and reduced FA was shown in NMOSD (p < 0.05) compared to HC, with all the effects, together with lesion load on T1WI and T2WI, being greater in patients with MS than in patients with NMOSD (p < 0.05). There was no significant difference in the time interval to follow-up in patients with MS (1.37 years) and NMOSD (1.25 years) (p > 0.05), during which there were significant changes in EDSS score between baseline and follow-up in NMOSD and MS patients (p < 0.05). There was a significantly reduced FA, and increased MD and RD in patients with MS (p < 0.05), but no significant changes in patients with NMOSD (p > 0.05).

CONCLUSIONS

Both MS and NMOSD have microstructure damage in white matter, while the progressive change in brain microstructural properties is observed in patients with MS but may not in patients with NMOSD in a short-term follow-up.

Out of balance: the role of evolutionary mismatches in the sex disparity in autoimmune disease

Over the past century autoimmune disease incidence has increased rapidly in (post-) industrialised, affluent societies, suggesting that changes in ecology and lifestyle are driving this development. Epidemiological studies show that (i) 80% of autoimmune disease patients are female, (ii) autoimmune diseases co-occur more often in women, and (iii) the incidence of some autoimmune diseases is increasing faster in women than in men. The female preponderance in autoimmunity is most pronounced between puberty and menopause, suggesting that diverging sex hormone levels during the reproductive years are implicated in autoimmune disease development. Using an evolutionary perspective, we build on the hypotheses that female immunity is cyclical in menstruating species and that natural selection shaped the female immune system to optimise the implantation and gestation of a semi-allogeneic foetus. We propose that cyclical immunomodulation and female immune tolerance mechanisms are currently out of balance because of a mismatch between the conditions under which they evolved and (post-)industrialised, affluent lifestyles. We suggest that current changes in autoimmune disease prevalence may be caused by increases in lifetime exposure to cyclical immunomodulation and ovarian hormone exposure, reduced immune challenges, increased reproductive lifespan, changed reproductive patterns, and enhanced positive energy balance associated with (post-)industrialised, affluent lifestyles. We discuss proximate mechanisms by which oestrogen and progesterone influence tolerance induction and immunomodulation, and review the effect of the menstrual cycle, pregnancy, and contraceptive use on autoimmune disease incidence and symptoms.

Neuroprotective Methodologies in the Treatment of Multiple Sclerosis Current Status of Clinical and Pre-clinical Findings

Multiple sclerosis is an idiopathic and autoimmune associated motor neuron disorder that affects myelinated neurons in specific brain regions of young people, especially females. MS is characterized by oligodendrocytes destruction further responsible for demyelination, neuroinflammation, mitochondrial abnormalities, oxidative stress and neurotransmitter deficits associated with motor and cognitive dysfunctions, vertigo and muscle weakness. The limited intervention of pharmacologically active compounds like interferon-β, mitoxantrone, fingolimod and monoclonal antibodies used clinically are majorly associated with adverse drug reactions. Pre-clinically, gliotoxin ethidium bromide mimics the behavioral and neurochemical alterations in multiple sclerosis- like in experimental animals associated with the down-regulation of adenyl cyclase/cAMP/CREB, which is further responsible for a variety of neuropathogenic factors. Despite the considerable investigation of neuroprotection in curing multiple sclerosis, some complications still remain. The available medications only provide symptomatic relief but do not stop the disease progression. In this way, the development of unused beneficial methods tends to be ignored. The limitations of the current steady treatment may be because of their activity at one of the many neurotransmitters included or their failure to up direct signaling flag bearers detailed to have a vital part in neuronal sensitivity, biosynthesis of neurotransmitters and its discharge, development, and separation of the neuron, synaptic versatility and cognitive working. Therefore, the current review strictly focused on the exploration of various clinical and pre-clinical features available for multiple sclerosis to understand the pathogenic mechanisms and to introduce pharmacological interventions associated with the upregulation of intracellular adenyl cyclase/cAMP/CREB activation to ameliorate multiple sclerosis-like features.

Sex dimorphism in an animal model of multiple sclerosis: Focus on pregnenolone synthesis

Neuroactive steroids, molecules produced from cholesterol in steroidogenic cells (i.e., peripheral glands and nervous system) are physiological modulators and protective agents of nervous function. A possible role for neuroactive steroids in the sex-dimorphic clinical manifestation, onset and progression of Multiple Sclerosis (MS) has been recently suggested. To explore this possibility, we assessed the synthesis of the first steroidogenic product (pregnenolone; PREG) in the spinal cord of experimental autoimmune encephalomyelitis rats, a MS model. Data obtained indicate that the synthesis of PREG in the spinal cord is altered by the pathology in a sex-dimorphic way and depending on the pathological progression. Indeed, in male spinal cord the synthesis was already decreased at the acute phase of the disease (i.e., 14 days post induction - dpi) and maintained low during the chronic phase (i.e., 45 dpi), while in females this effect was observed only at the chronic phase. Substrate availability had also a role in the sex-dimorphic kinetics. Indeed, at the chronic phase, male animals showed a reduction in the levels of free cholesterol coupled to alteration of cholesterol metabolism into oxysterols; these effects were not observed in female animals. These findings suggest that the comprehension of the neurosteroidogenic processes could be relevant to better understand the sexual dimorphism of MS and to possibly design sex-oriented therapeutic strategies based on neuroactive steroids.

Menopause in women with multiple sclerosis: A systematic review

AIM

Sex hormones have been suggested to have neuroprotective effects in the natural history of multiple sclerosis (MS), particularly in animal studies. The aim of the present review was to retrieve and systematically synthesize the evidence on the effect of menopause and hormonal replacement treatment (HRT) on the course of MS.

METHODS

A systematic literature search was conducted in the databases MEDLINE (accessed through PubMed), Scopus, clinicaltrials.gov and Cochrane Controlled Register of Trials (CENTRAL). Eligible studies were all those that included women with MS and reported on at least one of the following: a) disability and MS relapse rate before and after menopause, b) serum sex hormone concentrations, c) sexual function, d) age at menopause onset. Effects of HRT on MS clinical outcomes were also assessed.

RESULTS

Of the 4,102 retrieved studies, 28 were included in the systematic review. Of these, one reported the age at menopause for both controls and women with MS and found no difference between the two groups. There was no difference in the rates of relapse before and after menopause (risk ratio 1.21, 95 % confidence interval 0.91-1.61, p = 0.218). Two intervention studies reported beneficial effects of estrogen therapy on women with MS; however, the majority of women were premenopausal. Three studies addressed the issue of sexual dysfunction in women with MS, but information on hormonal parameters was limited.

CONCLUSIONS

The age at menopause is not associated with the presence of MS. The evidence on a potential causal effect of estrogen depletion on disability is inconclusive; still, relapse rate seems not be associated with menopause. The effect of HRT on the natural course of the disease remains to be defined.

Nicotinamide nucleotide transhydrogenase expression analysis in multiple sclerosis patients

Background: Nicotinamide nucleotide transhydrogenase (NNT) is a mitochondrial redox-induced proton pump that links NADPH synthesis to the mitochondrial metabolic pathway. It also participates in the regulation of immune responses. A long non-coding RNA namely NNT-antisense 1 (NNT-AS1) has been shown to be transcribed from the same locus and exert anti-proliferative effects in some tissues. Methods: In the current study, we evaluated expression of NNT and NNT-AS1 in peripheral blood of 50 relapsing-remitting multiple sclerosis patients compared with healthy subjects. The difference in NNT expression was significant in only in male subjects aged over 50 when compared with the corresponding control subgroup. Results: For NNT-AS1, based on the results of Quantile regression and adjustment of the effects of age and sex as well as the interaction between sex and disease status, no significant difference was found between cases and controls. Moreover, NNT and NNT-AS1 expressions were correlated with age in controls and in female subjects respectively. Conclusion: Finally, we assessed correlations between expressions of these genes and detected significant pairwise correlations between transcript levels of NNT and NNT-AS1 genes in both cases and controls. The current study highlights a gender-specific role for NNT in the pathogenesis of MS.

Hepatocellular carcinoma up-regulated long non-coding RNA: a putative marker in multiple sclerosis

Highly up-regulated in liver cancer (HULC) is a cancer-associated long non-coding RNA (lncRNA) which may regulate expression of other genes by working as a competing RNA for microRNAs. In the current study, we assessed transcript levels of this lncRNA in peripheral blood of multiple sclerosis (MS) patients and healthy persons to evaluate its possible role in the pathogenesis of this inflammatory disease and its diagnostic power. The results of Multilevel Bayesian showed no significant difference between cases and controls (P = 0.002, 95% confidence interval (CI) = [3.08, 13.3]). However, based on the results of Quantile regression, there was a significant difference in HULC expression between cases and controls after controlling the effects of sex and age (P = 0.002, 95% CI = [3.08, 13.3]) which shows different trends in males and females. HULC expression was inversely correlated with age of male subjects but not female subjects. HULC transcript levels had 91.1% accuracy in diagnosis of MS disease (Specificity: 80%, Sensitivity: 86.6%). The diagnostic power of HULC was higher in male subjects aged less than 50 years (AUC = 0.923, Specificity: 80%, Sensitivity: 100%). The present study shows the possibility of application of transcript levels of HULC as diagnostic marker in MS disease. However, future studies with larger sample sizes are necessary to validate our results.

Analogues of ERβ ligand chloroindazole exert immunomodulatory and remyelinating effects in a mouse model of multiple sclerosis

Pharmaceutical agents currently approved for the treatment of multiple sclerosis reduce relapse rates, but do not reverse or prevent neurodegeneration nor initiate myelin repair. The highly selective estrogen receptor (ER) β ligand chloroindazole (IndCl) shows particular promise promoting both remyelination while reducing inflammatory cytokines in the central nervous system of mice with experimental autoimmune encephalomyelitis. To optimize these benefits, we developed and screened seven novel IndCl analogues for their efficacy in promoting primary oligodendrocyte (OL) progenitor cell survival, proliferation, and differentiation in vitro by immunohistochemistry. Two analogues, IndCl-o-chloro and IndCl-o-methyl, induced proliferation and differentiation equivalent to IndCl and were selected for subsequent in vivo evaluation for their impact on clinical disease course, white matter pathology, and inflammation. Both compounds ameliorated disease severity, increased mature OLs, and improved overall myelination in the corpus callosum and white matter tracts of the spinal cord. These effects were accompanied by reduced production of the OL toxic molecules interferon-γ and chemokine (C-X-C motif) ligand, CXCL10 by splenocytes with no discernable effect on central nervous system-infiltrating leukocyte numbers, while IndCl-o-methyl also reduced peripheral interleukin (IL)−17. In addition, expression of the chemokine CXCL1, which is associated with developmental oligodendrogenesis, was upregulated by IndCl and both analogues. Furthermore, callosal compound action potential recordings from analogue-treated mice demonstrated a larger N1 component amplitude compared to vehicle, suggesting more functionally myelinated fibers. Thus, the o-Methyl and o-Chloro IndCl analogues represent a class of ERβ ligands that offer significant remyelination and neuroprotection as well as modulation of the immune system; hence, they appear appropriate to consider further for therapeutic development in multiple sclerosis and other demyelinating diseases.

Noradrenaline through β-adrenoceptor contributes to sexual dimorphism in primary CD4+ T-cell response in DA rat EAE model?

Males exhibit stronger sympathetic nervous system (SNS) activity, but weaker primary CD4+ T-cell (auto)immune responses. To test the role of catecholamines, major end-point SNS mediators, in this dimorphism, influence of propranolol (β-adrenoceptor blocker) on mitogen/neuroantigen-stimulated CD4+ T cells from female and male EAE rat draining lymph node (dLN) cell cultures was examined. Male rat dLNs exhibited higher noradrenaline concentration and frequency of β₂-adrenoceptor-expressing CD4+ T lymphocytes and antigen presenting cells. Propranolol, irrespective of exogenous noradrenaline presence, more prominently augmented IL-2 production and proliferation of CD4+ lymphocytes in male than female rat dLN cell cultures. In neuroantigen-stimulated dLN cells of both sexes propranolol increased IL-1β and IL-23/p19 expression and IL-17+ CD4+ cell frequency, but enhanced IL-17 production only in male rat CD4+ lymphocytes, thereby abrogating sexual dimorphism in IL-17 concentration observed in propranolol-free cultures. Thus, β-adrenoceptor-mediated signalling may contribute to sex bias in rat IL-17-producing cell secretory capacity.

Cholesterol level correlate with disability score in patients with relapsing-remitting form of multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is an autoimmune disease characterised by demyelination. There are many environmental factors that can affect the progression of this disease. It is necessary to better understand the impact of these factors in MS pathogenesis and progression.

OBJECTIVE

Present study investigates the relationship of total cholesterol serum levels and other parameters contributing to cardiovascular risk - homocysteine and serum lipid parameters (triglycerides, HDL, LDL) - with the progression of MS (EDSS score).

METHODS

The study involved 169 patients diagnosed with MS. Total homocysteine levels were measured by high-performance liquid chromatography. Serum lipid parameters were measured with enzymatic kits.

RESULTS

There was no difference observed between homocysteine levels in MS patients and controls. Dyslipidaemia seems to be associated with MS progression, particularly in women with relapsing-remitting form of MS.

CONCLUSION

Positive correlation of total and LDL cholesterol with disability score in patients with relapsing-remitting form of MS suggests that lipid parameters could have a negative effect on the disease progression.

Association of interleukin 6, interleukin 7 receptor alpha, and interleukin 12B gene polymorphisms with multiple sclerosis

Pro-inflammatory and anti-inflammatory cytokines have been shown to play a crucial role in the pathophysiology of multiple sclerosis (MS). We investigated the association between interleukin (IL) IL6-174 G/C (rs1800795), IL7RA C/T (rs6897932), and IL-12B A1188C (rs3212227) gene polymorphisms (SNPs) and MS. The study consisted of 297 unrelated MS patients and 135 healthy individuals. In IL6-174G/C (rs1800795), a significant association between the C allele and MS risk [OR 1.41, 95% CI (1.05-1.92); P = 0.025] was found. Carriage of genotypes CC and CG were more common in MS patients [OR 1.58, 95% CI (1.04-2.39); P = 0.031] and also in female MS patients [OR 1.68, 95% CI (1.02-2.79); P = 0.043]. However, after applying Bonferroni's correction the differences did not remain significant. No significant association between the IL7RA C/T (rs6897932) and IL12B A1188C (rs3212227) gene polymorphisms and MS susceptibility was observed. Regarding IL-12B A1188C (rs3212227), a significant association between the CC genotype and MS progression, expressed as MSSS, was demonstrated in the female MS group. Our results indicate that the distribution of IL6-174G/C (rs1800795) SNP was marginally associated with MS susceptibility. We also showed that IL-12B A1188C (rs3212227) can contribute to the progression of the disease in the Czech population.

Embolization of a large progressive symptomatic desmoid tumor in the rectus muscle of a female patient with multiple sclerosis: a case report

INTRODUCTION

Desmoid tumors are benign tumors, yet can lead to significant morbidity due to aggressive local expansions. Treatment starts with a wait-and-see policy, however, more aggressive treatments like broad margin resection surgery might be necessary in case of tumor progression.

PATIENTS AND METHODS

We report the case of a 26-year-old female with a symptomatic desmoid tumor in the left rectus muscle. The initial wait-and-see policy led to an increase in tumor size and progression of symptoms. Computed tomography (CT) angiography revealed a dominant arterial blood supply via a branch of the inferior epigastric artery. We then performed a super selective embolization of the dominant arterial blood supply, to avoid the need for broad margin resection.

RESULTS

At three months follow-up, the patient was asymptomatic and magnetic resonance imaging (MRI) showed no residual tumor. At nine months follow-up, MRI scan reconfirmed the successful outcome.

CONCLUSIONS

Embolization of a primary supplying vessel of a desmoid tumor is a viable treatment option. However, scientific evidence remains limited and further research is mandatory for inclusion in evidence based treatment algorithms.

An Update on the Use of Disease-Modifying Therapy in Pregnant Patients with Multiple Sclerosis

The active management of multiple sclerosis (MS) has been made possible during the last two decades with the advent of disease-modifying therapies (DMTs), leading to improved clinical outcomes for many patients. Furthermore, with the realization that MS does not adversely affect pregnancy outcome and that pregnancy does not have an overall negative impact on the long-term disease course of MS, the importance of appropriate counseling and discussion of future pregnancy plans with women of childbearing age is greater than ever. Although several DMTs are licensed for the treatment of MS, none are specifically approved for use during pregnancy or breastfeeding and the use of DMTs during these periods frequently gives rise to concerns regarding potential risks to the fetus. The outcomes of studies in patients with MS treated with DMTs during pregnancy and immediately postpartum have been the focus of several recently published papers. Given the high level of interest surrounding the prescribing of DMTs for MS patients of childbearing age, and the lack of clear guidance in this respect, the current review presents an up-to-date overview of new data, including observational data on real-world outcomes, that have been published during the last 2 years, and could inform future prescribing decisions.

Peripheral Inflammation and Demyelinating Diseases

In recent decades, several neurodegenerative diseases have been shown to be exacerbated by systemic inflammatory processes. There is a wide range of literature that demonstrates a clear but complex relationship between the central nervous system (CNS) and the immunological system, both under naïve or pathological conditions. In diseased brains, peripheral inflammation can transform "primed" microglia into an "active" state, which can trigger stronger pathological responses. Demyelinating diseases are a group of neurodegenerative diseases characterized by inflammatory lesions associated with demyelination, which in turn induces axonal damage, neurodegeneration, and progressive loss of function. Among them, the most important are multiple sclerosis (MS) and neuromyelitis optica (NMO). In this review, we will analyze the effect of specific peripheral inflammatory stimuli in the progression of demyelinating diseases and discuss their animal models. In most cases, peripheral immune stimuli are exacerbating.

Loss of Nrf2 exacerbates the visual deficits and optic neuritis elicited by experimental autoimmune encephalomyelitis

PURPOSE

Optic neuritis, inflammation of the optic nerve, is experienced by most patients with multiple sclerosis (MS) and is typically characterized by episodes of acute, monocular vision loss. These episodes of inflammation can lead to damage or degeneration of the retinal ganglion cells (RGCs), the axons of which comprise the optic nerve. Experimental autoimmune encephalomyelitis (EAE) is a well-established model of MS in which mice are immunized to produce a neuroautoimmunity that recapitulates the cardinal hallmarks of human disease, namely, inflammation, demyelination, and neurodegeneration of the brain, spinal cord, and optic nerve. Inflammation-associated oxidative stress plays a key role in promoting spinal cord damage in EAE. However, the role of oxidative stress in optic neuritis and the associated visual deficits has not been studied. To address this gap in research, we sought to determine how a deficiency in the master antioxidant transcription factor (using nuclear factor-E2-related factor [Nrf2]-deficient mice) affects visual pathology in the EAE model.

METHODS

EAE was induced in 8-week-old wild-type (WT) and Nrf2 knockout (KO) mice by immunization against the myelin oligodendrocyte glycoprotein (MOG) peptide antigen. Motor deficits were monitored daily, as was visual acuity using the established functional optokinetic tracking (OKT) assay. Mice were euthanized 21 days post-immunization for histological analyses. The optic nerves were paraffin-embedded and stained with hematoxylin and eosin (H&E) or immune cell type-specific antibodies to analyze inflammatory infiltrates. The retinas were flatmounted and stained with an RGC-specific antibody, and the RGCs were counted to assess neurodegeneration. T-helper (Th) cell-associated cytokines were measured in spleens with enzyme-linked immunosorbent assay (ELISA). Immune analyses of healthy, non-EAE mice were characterized with flow cytometry to assess the baseline immune cell profiles.

RESULTS

Female Nrf2 KO mice exhibited more severe EAE-induced motor deficits compared with female WT mice. In both genders, EAE elicited more severe visual acuity deficits, inflammation of the optic nerve, and RGC degeneration in KO mice compared with their strain- and age-matched WT counterparts. Visual acuity deficits were primarily present in (and only exacerbated in) one eye of each mouse. Excess inflammatory cells within the optic nerves of the KO mice were primarily comprised of T-cells, and greater RGC degeneration in the KO mice was most prevalent in the central retina compared with the peripheral retina. Nrf2 KO spleens exhibited an increased Th1- but not Th17-associated immune response. This enhanced pathology in the KO mice was not due to global differences in immune system development between the two genotypes.

CONCLUSIONS

This is the first study to report that genetic ablation of Nrf2 exacerbates visual deficits, inflammation of the optic nerve, and RGC degeneration in a murine model of MS, suggesting that Nrf2 plays a neuro- and cytoprotective role in EAE-associated optic neuritis.

Sex Difference in Oxidative Stress Parameters in Spinal Cord of Rats with Experimental Autoimmune Encephalomyelitis: Relation to Neurological Deficit

The study examined (a) whether there is sex difference in spinal cord and plasma oxidative stress profiles in Dark Agouti rats immunised for experimental autoimmune encephalomyelitis (EAE), the principal experimental model of multiple sclerosis, and (b) whether there is correlation between the oxidative stress in spinal cord and neurological deficit. Regardless of rat sex, with the disease development xanthine oxidase (XO) activity and inducible nitric oxide synthase (iNOS) mRNA expression increased in spinal cord, whereas glutathione levels decreased. This was accompanied by the rise in spinal cord malondialdehyde level. On the other hand, with EAE development superoxide dismutase (SOD) activity decreased, while O₂^- concentration increased only in spinal cord of male rats. Consequently, SOD activity was lower, whereas O₂^- concentration was higher in spinal cord of male rats with clinically manifested EAE. XO activity and iNOS mRNA expression were also elevated in their spinal cord. Consistently, in the effector phase of EAE the concentration of advanced oxidation protein product (AOPP) was higher in spinal cord of male rats, which exhibit more severe neurological deficit than their female counterparts. In as much as data obtained in the experimental models could be translated to humans, the findings may be relevant for designing sex-specific antioxidant therapeutic strategies. Furthermore, the study indicated that the increased pro-oxidant-antioxidant balance in plasma may be an early indicator of EAE development. Moreover, it showed that plasma AOPP level may indicate not only actual activity of the disease, but also serve to predict severity of its course.

17β-Estradiol Promotes Schwann Cell Proliferation and Differentiation, Accelerating Early Remyelination in a Mouse Peripheral Nerve Injury Model

Estrogen induces oligodendrocyte remyelination in response to demyelination in the central nervous system. Our objective was to determine the effects of 17β-estradiol (E2) on Schwann cell function and peripheral nerve remyelination after injury. Adult male C57BL/6J mice were used to prepare the sciatic nerve transection injury model and were randomly categorized into control and E2 groups. To study myelination in vitro, dorsal root ganglion (DRG) explant culture was prepared using 13.5-day-old mouse embryos. Primary Schwann cells were isolated from the sciatic nerves of 1- to 3-day-old Sprague–Dawley rats. Immunostaining for myelin basic protein (MBP) expression and toluidine blue staining for myelin sheaths demonstrated that E2 treatment accelerates early remyelination in the “nerve bridge” region between the proximal and distal stumps of the transection injury site in the mouse sciatic nerve. The 5-bromo-2′-deoxyuridine incorporation assay revealed that E2 promotes Schwann cell proliferation in the bridge region and in the primary culture, which is blocked using AKT inhibitor MK2206. The in vitro myelination in the DRG explant culture determined showed that the MBP expression in the E2-treated group is higher than that in the control group. These results show that E2 promotes Schwann cell proliferation and myelination depending on AKT activation.

Chronic iron overload induces gender-dependent changes in iron homeostasis, lipid peroxidation and clinical course of experimental autoimmune encephalomyelitis

To analyze iron- and gender-dependent mechanisms possibly involved in pathogenesis of multiple sclerosis (MS) in this study we evaluated the effects of iron overload (IO) on iron status and lipid peroxidation processes (LPO) in tissues of female and male DA rats during chronic relapsing experimental autoimmune encephalomyelitis, a well-established MS animal model. Rats were treated by iron sucrose (75mg/kg bw/day) or with saline solution during two weeks before the sensitization with bovine brain homogenate in complete Freund's adjuvant. Clinical signs of EAE were monitored during 29 days. Serum and tissues of CNS and liver were sampled before immunization and at day 13th post immunization (during acute phase of EAE). The determination of ferritin, iron, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) and evaluation of histopathology were performed by ELISA, ICP spectrometry and immunohistochemistry. Results showed that IO in female EAE rats accelerated the onset of disease. In contrast, in male rats it accelerated the progression of disease and increased the mortality rate. During acute phase of EAE female IO rats sequestered more Fe in the liver, spinal cord and in the brain and produced more ferritin than male EAE rats. Male rats, however, reacted on IO by higher production of MDA or 4-HNE in the neural tissues and showed greater signs of plaque formation and gliosis in spinal cord. The data point to sexual dimorphism in mechanisms that regulate peripheral and brain iron homeostasis and imply that men and women during MS might be differentially vulnerable to exogenous iron overload.

Interleukin-17A Levels Vary in Relapsing-Remitting Multiple Sclerosis Patients in Association with Their Age, Treatment and the Time of Evolution of the Disease

OBJECTIVE

The present study was specifically designed to discern the possible existence of subgroups of patients with the relapsing-remitting form of multiple sclerosis (RRMS) depending on their gender, age, disease stage (relapsing or remitting), time of disease evolution and response to different treatments.

METHODS

We analyzed samples from patients with RRMS (50 females and 32 males) and healthy individuals (25 matched for age and gender) and determined serum concentrations of IFN-γ, IL-10 and IL-17A. We stratified patients by gender, age, treatment and disease evolution time, and subsequently correlated these independent variables with the concentrations of the previously mentioned cytokines.

RESULTS

We provided initial evidence that treatment exerted possible differential effects depending on the time of disease duration. Results evidence the existence of different subgroups of patients with MS, who can be classified as follows: (a) male or female under or over 40 years of age; (b) disease duration according to treatment (under or over 8 years of disease); (c) classification according to fluctuating levels of IFN-γ, IL-10 and IL-17A in the following three stages of disease evolution: <5 years, between 5 and 10 years, and >10 years.

CONCLUSION

These subgroups must be taken into account for the clinical follow-up of patients with MS in order to provide them with a better and more personalized treatment, and also for a deep and detailed analysis of progressive disease, in an attempt to comprehend fluctuations and clinical variability by means of a better understanding of intrinsically physiological variables of the disease.

Remyelination Therapy in Multiple Sclerosis

Multiple sclerosis (MS) is an immune-mediated disorder of the central nervous system that results in destruction of the myelin sheath that surrounds axons and eventual neurodegeneration. Current treatments approved for the treatment of relapsing forms of MS target the aberrant immune response and successfully reduce the severity of attacks and frequency of relapses. Therapies are still needed that can repair damage particularly for the treatment of progressive forms of MS for which current therapies are relatively ineffective. Remyelination can restore neuronal function and prevent further neuronal loss and clinical disability. Recent advancements in our understanding of the molecular and cellular mechanisms regulating myelination, as well as the development of high-throughput screens to identify agents that enhance myelination, have lead to the identification of many potential remyelination therapies currently in preclinical and early clinical development. One problem that has plagued the development of treatments to promote remyelination is the difficulty in assessing remyelination in patients with current imaging techniques. Powerful new imaging technologies are making it easier to discern remyelination in patients, which is critical for the assessment of these new therapeutic strategies during clinical trials. This review will summarize what is currently known about remyelination failure in MS, strategies to overcome this failure, new therapeutic treatments in the pipeline for promoting remyelination in MS patients, and new imaging technologies for measuring remyelination in patients.

Retinal nerve fiber layer sector-specific compromise in relapsing and remitting multiple sclerosis

Objective

To evaluate quadrant and sector retinal nerve fiber layer (RNFL) thickness and total macular volume (TMV) in relapsing–remitting multiple sclerosis (RR-MS) patients.

Methods

Optical coherence tomography measures of RNFL and TMV were studied in 321 eyes without prior optic neuritis (ON) (MS unaffected), 151 eyes with prior ON (MS affected), and 148 healthy control eyes.

Results

Mean RNFL thickness was significantly lower in the MS affected and MS unaffected groups relative to the control group (p < 0.0001). RNFL thicknesses in the superior, inferior, and temporal quadrants were significantly reduced in MS unaffected (113 ± 15 μm, 119 ± 17 μm, 63 ± 13 μm) (p < 0.001) and MS affected groups (99 ± 19 μm, 103 ± 21 μm, 51 ± 13 μm) (p < 0.0001) compared with that in controls (120 ± 14 μm, 128 ± 15 μm, 69 ± 8 μm, respectively). TMV was significantly reduced in both the MS affected and MS unaffected groups compared with that in the controls (p < 0.0001).

Conclusion

Quadrant, sector, and PMB RNFL thicknesses are significant individual measures in RR-MS for both affected and unaffected eyes and may prove valuable in future investigations including biomarker and outcomes research.

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We detailed RNFL quadrant and sector segmentation analysis in multiple sclerosis.

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RNFL sector thicknesses were lower in 2 affected eyes relative to 1 affected eye.

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PMB thickness distinguishes MS affected and MS unaffected groups from controls.

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TMV thickness distinguishes MS affected and MS unaffected groups from controls.

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EDSS correlated with RNFL for unaffected group and TMV for affected group.

Male rats develop more severe experimental autoimmune encephalomyelitis than female rats: sexual dimorphism and diergism at the spinal cord level

Compared with females, male Dark Agouti (DA) rats immunized for experimental autoimmune encephalomyelitis (EAE) with rat spinal cord homogenate in complete Freund's adjuvant (CFA) exhibited lower incidence of the disease, but the maximal neurological deficit was greater in the animals that developed the disease. Consistently, at the peak of the disease greater number of reactivated CD4+CD134+CD45RC- T lymphocytes was retrieved from male rat spinal cord. Their microglia/macrophages were more activated and produced greater amount of prototypic proinflammatory cytokines in vitro. Additionally, oppositely to the expression of mRNAs for IL-12/p35, IL-10 and IL-27/p28, the expression of mRNA for IL-23/p19 was upregulated in male rat spinal cord mononuclear cells. Consequently, the IL-17+:IFN-γ+ cell ratio within T lymphocytes from their spinal cord was skewed towards IL-17+ cells. Within this subpopulation, the IL-17+IFN-γ+:IL-17+IL-10+ cell ratio was shifted towards IL-17+IFN-γ+ cells, which have prominent tissue damaging capacity. This was associated with an upregulated expression of mRNAs for IL-1β and IL-6, but downregulated TGF-β mRNA expression in male rat spinal cord mononuclear cells. The enhanced GM-CSF mRNA expression in these cells supported the greater pathogenicity of IL-17+ T lymphocytes infiltrating male spinal cord. In the inductive phase of the disease, contrary to the draining lymph node, in the spinal cord the frequency of CD134+ cells among CD4+ T lymphocytes and the frequency of IL-17+ cells among T lymphocytes were greater in male than in female rats. This most likely reflected an enhanced transmigration of mononuclear cells into the spinal cord (judging by the lesser spinal cord CXCL12 mRNA expression), the greater frequency of activated microglia/macrophages and the increased expression of mRNAs for Th17 polarizing cytokines in male rat spinal cord mononuclear cells. Collectively, the results showed cellular and molecular mechanisms underlying the target organ specific sexual dimorphism in the T lymphocyte-dependent immune/inflammatory response, and suggested a substantial role for the target organ in shaping the sexually dimorphic clinical outcome of EAE.

Association of the SPT2 chromatin protein domain containing 1 gene rs17579600 polymorphism and serum lipid traits

SPT2 chromatin protein domain containing 1 gene (SPTY2D1) is a candidate gene for dyslipidemia. The single nucleotide polymorphism (SNP) of rs7934205 near SPTY2D1 locus was ethnic- and sex-specific associated with serum lipid levels in our previous study. Whether SPTY2D1 rs17579600 SNP and several environmental factors are associated with serum lipid profiles is unknown. A total of 712 participants of Han and 689 unrelated individuals of Mulao were included. The genotype and allele frequencies of SPTY2D1 rs17579600 SNP were different between the Han and Mulao populations (TT, 74.3% vs. 55.7%; TC, 17.6% vs. 31.2%, CC, 8.1% vs. 13.1%, P = 0.028; T, 83.1% vs. 71.3%; C, 16.9% vs. 28.7%, P = 0.044), and between males and females in the both ethnic groups. The levels of serum apolipoprotein (Apo) A1 in Han, triglyceride (TG) in Mulao, and total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), ApoA1 and ApoB in Mulao males were difference among the genotypes. The C allele carriers had higher ApoA1 in Han, lower TG in Mulao, and lower TC, LDL-C and ApoB and higher ApoA1 in Mulao males than the C allele non-carriers. Serum lipid parameters were also associated with several environmental factors in both ethnic groups. The differences suggesting there may be a racial/ethnic- and/or sex-specific association between the SPTY2D1 rs17579600 SNP and serum lipid parameters in some ethnic groups.

Pharmacotherapy with 17β-estradiol and progesterone prevents development of mouse experimental autoimmune encephalomyelitis

BACKGROUND

Pregnant women with multiple sclerosis (MS) show disease remission in the third trimester concomitant with high circulating levels of sex steroids. Rodent experimental autoimmune encephalomyelitis (EAE) is an accepted model for MS. Previous studies have shown that monotherapy with estrogens or progesterone exert beneficial effects on EAE. The aim of the present study was to determine if estrogen and progesterone cotherapy of C57BL/6 female mice provided substantial protection from EAE.

METHODS

A group of mice received single pellets of progesterone (100 mg) and 17 β-estradiol (2.5 mg) subcutaneously 1 week before EAE induction, whereas another group were untreated before EAE induction. On day 16 we compared the two EAE groups and control mice in terms of clinical scores, spinal cord demyelination, expression of myelin basic protein and proteolipid protein, macrophage cell infiltration, neuronal expression of brain-derived neurotrophic factor mRNA and protein, and the number of glial fribrillary acidic protein (GFAP)-immunopositive astrocytes.

RESULTS

Clinical signs of EAE were substantially attenuated by estrogen and progesterone treatment. Steroid cotherapy prevented spinal cord demyelination, infiltration of inflammatory cells and GFAP+ astrogliocytes to a great extent. In motoneurons, expression of BDNF mRNA and protein was highly stimulated, indicating concomitant beneficial effects of the steroid on neuronal and glial cells.

CONCLUSIONS

Cotherapy with estrogen and progesterone inhibits the development of major neurochemical abnormalities and clinical signs of EAE. We suggest that a combination of neuroprotective, promyelinating and immuno-suppressive mechanisms are involved in these beneficial effects.

The role of epidemiology in MS research: Past successes, current challenges and future potential

Multiple sclerosis (MS) is a multifaceted condition, with a range of environmental, behavioural and genetic factors implicated in its aetiology and clinical course. Successes in advancing our appreciation of the roles of Epstein-Barr virus, vitamin D/UV and the HLA-DRB1 locus; and our greater understanding of these and related factors’ modes of action in MS and other conditions, can be attributed in no small part to the work of generations of epidemiologists. Hardly content to rest on our laurels, however, there are yet a range of unsolved conundrums in MS, including some changes in epidemiological characteristics (e.g. increasing incidence and sex ratio), to say nothing of the unresolved parts regarding what underlies MS risk and its clinical course. There is evidence that epidemiology will continue to play a crucial role in unravelling the architecture of MS causation and clinical course. While classic epidemiological methods are ongoing, novel avenues for research include gene-environment interaction studies, the world of ‘-omic’ research, and the utilisation of mobile and social media tools to both access and track study populations, which means that the epidemiological discoveries of the past century may be but a glimpse of our understanding in the next few decades.

Neuroactive steroid levels in plasma and cerebrospinal fluid of male multiple sclerosis patients

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 in pregnenolone and isopregnanolone levels associated with a decrease in 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 in pregnenolone, progesterone, and dihydrotestosterone and a decrease in dihydroprogesterone and tetrahydroprogesterone levels were reported. This 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. We here demonstrated that, the cerebrospinal fluid and plasma levels of several neuroactive steroids are modified in relapsing remitting multiple sclerosis male patients. Interestingly, we reported for the first time that, the levels of progesterone and testosterone metabolites are deeply affected in cerebrospinal fluid. These findings may have an important relevance in therapeutic and/or diagnostic field of multiple sclerosis.

Raloxifene suppresses experimental autoimmune encephalomyelitis and NF-κB-dependent CCL20 expression in reactive astrocytes

Recent clinical data have led to the consideration of sexual steroids as new potential therapeutic tools for multiple sclerosis. Selective estrogen receptor modulators can exhibit neuroprotective effects like estrogen, with fewer systemic estrogen side effects than estrogen, offering a more promising therapeutic modality for multiple sclerosis. The important role of astrocytes in a proinflammatory effect mediated by CCL20 signaling on inflammatory cells has been documented. Their potential contribution to selective estrogen receptor modulator-mediated protection is still unknown. Using a mouse model of chronic neuroinflammation, we report that raloxifene, a selective estrogen receptor modulator, alleviated experimental autoimmune encephalomyelitis–an animal model of multiple sclerosis–and decreased astrocytic production of CCL20. Enzyme-linked immunosorbent assay, immunohistochemistry imaging and transwell migration assays revealed that reactive astrocytes express CCL20, which promotes Th17 cell migration. In cultured rodent astrocytes, raloxifene inhibited IL-1β-induced CCL20 expression and chemotaxis ability for Th17 migration, whereas the estrogen receptor antagonist ICI 182,780 blocked this effect. Western blotting further indicated that raloxifene suppresses IL-1β-induced NF-κB activation (phosphorylation of p65) and translocation but does not affect phosphorylation of IκB. In conclusion, these data demonstrate that raloxifene provides robust neuroprotection against experimental autoimmune encephalomyelitis, partially via an inhibitory action on CCL20 expression and NF-κB pathways in reactive astrocytes. Our results contribute to a better understanding of the critical roles of raloxifene in treating experimental autoimmune encephalomyelitis and uncover reactive astrocytes as a new target for the inhibitory action of estrogen receptors on chemokine CCL20 expression.

Sex steroids and neuroprotection in spinal cord injury: a review of preclinical investigations

Spinal cord injury (SCI) is a debilitating condition that affects motor, sensory and autonomic functions. Subsequent to the first mechanical trauma, secondary events, which include inflammation and glial activation, exacerbate tissue damage and worsen functional deficits. Although these secondary injury mechanisms are amenable to therapeutic interventions, the efficacy of current approaches is inadequate. Further investigations are necessary to implement new therapies that can protect neural cells and attenuate some of the detrimental effects of inflammation while promoting regeneration. Studies on different animal models of SCI indicated that sex steroids, especially 17β-estradiol and progesterone, exert neuroprotective, anti-apoptotic and anti-inflammatory effects, ameliorate tissue sparing and improve functional deficits in SCI. As sex steroid receptors are expressed in a variety of cells including neurons, glia and immune system-related cells which infiltrate the injury epicenter, sex steroids could impact multiple processes simultaneously and in doing so, influence the outcomes of SCI. However, the translation of these pre-clinical findings into the clinical setting presents challenges such as the narrow therapeutic time window of sex steroid administration, the diversity of treatment regimens that have been employed in animal studies and the lack of sufficient information regarding the persistence of the effects in chronic SCI. The current review will summarize some of the major findings in this field and will discuss the challenges associated with the implementation of sex steroids as a promising treatment in human SCI.

Neuroendocrine immunoregulation in multiple sclerosis

Currently, it is generally accepted that multiple sclerosis (MS) is a complex multifactorial disease involving genetic and environmental factors affecting the autoreactive immune responses that lead to damage of myelin. In this respect, intrinsic or extrinsic factors such as emotional, psychological, traumatic, or inflammatory stress as well as a variety of other lifestyle interventions can influence the neuroendocrine system. On its turn, it has been demonstrated that the neuroendocrine system has immunomodulatory potential. Moreover, the neuroendocrine and immune systems communicate bidirectionally via shared receptors and shared messenger molecules, variously called hormones, neurotransmitters, or cytokines. Discrepancies at any level can therefore lead to changes in susceptibility and to severity of several autoimmune and inflammatory diseases. Here we provide an overview of the complex system of crosstalk between the neuroendocrine and immune system as well as reported dysfunctions involved in the pathogenesis of autoimmunity, including MS. Finally, possible strategies to intervene with the neuroendocrine-immune system for MS patient management will be discussed. Ultimately, a better understanding of the interactions between the neuroendocrine system and the immune system can open up new therapeutic approaches for the treatment of MS as well as other autoimmune diseases.

Association between multiple sclerosis and chronic periodontitis: a population-based pilot study

BACKGROUND AND PURPOSE

The pathogenesis of multiple sclerosis (MS) is still not fully understood, but multiple infections are known to be crucial in the development of the disease. Periodontitis caused by periodontopathic polymicrobial infections is among the most common chronic infectious disorders. This case-control study aimed to investigate the association between chronic periodontitis (CP) and MS using a population-based dataset in Taiwan.

METHODS

This study included 316 cases who had a diagnosis of MS and 1580 randomly selected controls. We performed conditional logistic regressions to investigate the association between MS and having been previously diagnosed with CP.

RESULTS

The results reveal that the prevalence of earlier CP was 25.6% and 15.4% for cases and controls, respectively (P < 0.001). Conditional logistic regression analysis revealed that cases were 1.86 [95% confidence interval (CI) = 1.39-2.48] times as likely as controls to have been previously diagnosed with CP, after adjusting for sociodemographic characteristics as well as hyperlipidemia, hypertension, coronary heart disease, alcohol abuse/alcohol-dependence syndrome, tobacco use disorder and chronic obstructive pulmonary disease. After analyzing by gender, it was realized that while female cases had a higher chance than female controls of having earlier CP (adjusted odds ratio = 2.08; 95% CI = 1.49-2.95), there was no statistical association detected between these two conditions in men.

CONCLUSIONS

This study provides evidence for an association between CP and MS in female, but not male, subjects. Further epidemiological studies are needed to confirm the association and gender-specific differences found in the present study.

Sex differences in the physiology and pharmacology of the lower urinary tract

Sexual dimorphism is not only noticed in the prevalence of many diseases, but also in multiple physiological functions in the body. This review has summarized findings from published literature on the sex differences of the pathophysiology and pharmacology of the lower urinary tract (LUT) of humans and animals. Sex differences have been found in several key areas of the LUT, such as overactive bladder, expression and function of neurotransmitter receptors in the bladder and urethra, and micturition patterns in humans and animals. It is anticipated that this review will not only evoke renewed interest for further research on the mechanism of sex differences in the pathophysiology of the LUT (especially for overactive bladder), but might also open up the possibilities for gender-based drug development by pharmaceutical industries in order to find separate cures for men and women with diseases of the LUT.

The chronic blockade of angiotensin I-converting enzyme eliminates the sex differences of serum cytokine levels of spontaneously hypertensive rats

Sex hormones modulate the action of both cytokines and the renin-angiotensin system. However, the effects of angiotensin I-converting enzyme (ACE) on the proinflammatory and anti-inflammatory cytokine levels in male and female spontaneously hypertensive rats (SHR) are unclear. We determined the relationship between ACE activity, cytokine levels and sex differences in SHR. Female (F) and male (M) SHR were divided into 4 experimental groups each (n = 7): sham + vehicle (SV), sham + enalapril (10 mg/kg body weight by gavage), castrated + vehicle, and castrated + enalapril. Treatment began 21 days after castration and continued for 30 days. Serum cytokine levels (ELISA) and ACE activity (fluorimetry) were measured. Male rats exhibited a higher serum ACE activity than female rats. Castration reduced serum ACE in males but did not affect it in females. Enalapril reduced serum ACE in all groups. IL-10 (FSV = 16.4 ± 1.1 pg/mL; MSV = 12.8 ± 1.2 pg/mL), TNF-α (FSV = 16.6 ± 1.2 pg/mL; MSV = 12.8 ± 1 pg/mL) and IL-6 (FSV = 10.3 ± 0.2 pg/mL; MSV = 7.2 ± 0.2 pg/mL) levels were higher in females than in males. Ovariectomy reduced all cytokine levels and orchiectomy reduced IL-6 but increased IL-10 concentrations in males. Castration eliminated the differences in all inflammatory cytokine levels (IL-6 and TNF-α) between males and females. Enalapril increased IL-10 in all groups and reduced IL-6 in SV rats. In conclusion, serum ACE inhibition by enalapril eliminated the sexual dimorphisms of cytokine levels in SV animals, which suggests that enalapril exerts systemic anti-inflammatory and anti-hypertensive effects.

Hormone and immune system interactions in demyelinating disease

The immune, endocrine and nervous systems communicate with each other through a myriad of molecules including cytokines, hormones and neurotransmitters. Alterations in the balance of the products of these systems affect susceptibility to autoimmune disease and also the progression of disease. One of the most intensely studied autoimmune diseases is multiple sclerosis (MS). The purpose of this review is to explore the relationships between sex hormones and MS disease progression and to attempt to understand the paradox that although women are more likely to develop MS, female sex hormones appear to be beneficial in symptom amelioration. The proposed mechanisms of the therapeutic action of estrogens will be discussed with respect to T cell polarization and also on CNS cell populations. Investigations into the pathogenesis of multiple sclerosis (MS) and animal models of MS have given insights into the interactions between the neuroendocrine systems and provide important potential therapeutic venues that may be expanded to other autoimmune and neurodegenerative conditions.

The relation between peptide hormones and sex hormone in patients with multiple sclerosis

BACKGROUND

Hormones can play a significant role in the pathogenesis of multiple sclerosis (MS). The aim of this study was to compare levels of ghrelin, leptin, and testosterone hormones of MS patients with healthy subjects, and assess the relationship between levels of peptide hormone and sex hormones in MS patients.

METHODS

35 MS patients with definite relapsing remitting multiple sclerosis (RRMS) (male = 9, female = 26) and 13 healthy subjects (male = 4, female = 9) were enrolled in the study. Levels of serum ghrelin, leptin, and testosterone hormones were measured in this study. ANOVA and Pearson correlation were used for data analysis (P < 0.05).

RESULTS

The female and male participants of the patient group were compared with the healthy group. No significant differences were found in serum of leptin, ghrelin, testosterone, ghrelin/leptin, and testosterone/leptin (P < 0.05). Spearman correlation coefficient showed that leptin had a significant negative correlation with the variability of testosterone (r = -1.00) in the healthy male group. Moreover, leptin had a significant positive correlation with the variability of BMI (r = 0.68) and weight (r = 0.59), at the 0.01 level (2-tailed), in the female patient group. In addition, in the healthy male group, ghrelin had a significant negative correlation with the variability of weight (r = -1.00).

CONCLUSION

According to the results, there was no significant difference between peptide and sex hormones of MS patients and healthy persons. Furthermore, there was no significant relationship between peptide and sex hormones of MS patients and healthy persons.

Sex-specific differences in retinal nerve fiber layer thinning after acute optic neuritis

OBJECTIVE

The primary objective of this study was to explore the potential influence of gender on recovery from optic neuritis (ON) by determining whether differences in retinal nerve fiber layer (RNFL) thickness can be detected between men and women 6 months after an ON event.

METHODS

In this prospective cohort study, 39 men and 105 women with acute ON underwent repeat visual and optical coherence tomography (OCT) testing. The main outcome measures were change in RNFL measurements for male and female patients 6 months after ON.

RESULTS

Men were older (mean age = 39 years) than women (35 years) (p = 0.05) in this study, and more men (62%) than women (41%) had a diagnosis of relapsing-remitting multiple sclerosis (MS) (p = 0.02). Because age and MS subtype were 2 significant covariates, both variables were controlled for in multiple regression analyses. Other covariates controlled for in the multivariate regression included disease duration (years), use of disease-modifying therapy (yes/no), and use of high-dose corticosteroids for acute ON (yes/no). After 6 months, mean RNFL values were lower in men (74 μm) than women (91 μm) (p < 0.001). Men showed more apparent change in RNFL thickness in their ON eyes from baseline to 6 months after ON than women (p = 0.003).

CONCLUSIONS

There may be differences in recovery between men and women after ON, which can be difficult to detect with conventional visual testing. Our findings raise interesting questions about the potential influence of gender in MS, which may be explored in future studies.