Estriol-mediated neuroprotection in multiple sclerosis localized by voxel-based morphometry

Neurologic Care for Transgender and Gender-Diverse People: A Review of Current Evidence and Clinical Implications

Purpose of Review

To summarize the literature on neurologic care for transgender and gender-diverse (TGD) people and provide implications for clinical practice.

Recent Findings

There are limited data on the frequency and management of neurologic conditions among TGD people. TGD people have a higher prevalence of various neurologic conditions compared with cisgender or general population cohorts, including migraine, subjective cognitive decline, sleep disturbances, functional disorders, and cerebrovascular disease. Gender-affirming hormone therapy interacts with commonly prescribed neurologic medications and increases stroke risk among transfeminine people. Sex hormones and sex chromosomes may play a role in neurodegeneration and disability progression in neuroimmunologic diseases. Clitoral reduction surgeries on intersex children can cause neurologic disability and sexual dysfunction in adulthood. Socioeconomic disparities among TGD people contribute to health care barriers.

Summary

Neurologists should consider the unique experiences and health care needs of TGD people in their clinical practice and research protocols.

Imaging phenotypic differences in multiple sclerosis: at the crossroads of aging, sex, race, and ethnicity

Clear sex differences are observed in clinical and imaging phenotypes of multiple sclerosis (MS), which evolve significantly over the age spectrum, and more specifically, during reproductive milestones such as pregnancy and menopause. With neuroimaging being an outcome measure and also a key subclinical biomarker of subsequent clinical phenotype in MS, this comprehensive review aims to provide an overview of sex and hormone differences in structural and functional imaging biomarkers of MS, including lesion burden and location, atrophy, white matter integrity, functional connectivity, and iron distribution. Furthermore, how therapies aimed at altering sex hormones can impact imaging of women and men with MS over the lifespan is discussed. This review also explores the key intersection between age, sex, and race/ethnicity in MS, and how this intersection may affect imaging biomarkers of MS.

Nestorone (segesterone acetate) effects on neuroregeneration

Nestorone® (segesterone acetate) is a progestin with a chemical structure closely related to progesterone with high affinity and selectivity for the progesterone receptor without significant interaction with other steroid receptors. It has been developed for female and male contraception and is FDA-approved in a first long-acting contraceptive vaginal system for female contraception. Its safety has been extensively demonstrated in both preclinical and clinical studies for contraceptive indications. Nestorone was found to display neuroprotective and neuroregenerative activity in animal models of various central nervous system diseases, including multiple sclerosis, stroke, and amyotrophic lateral sclerosis. Reviewed herein are neuroprotective and myelin- regenerating properties of Nestorone in various animal models and its translational potential as a therapeutic agent for debilitating neurological diseases for which limited therapeutic options are available (Table 1).

Clinical and Treatment Considerations for the Pediatric and Aging Patients with Multiple Sclerosis

Chronologic aging is associated with multiple pathologic and immunologic changes that impact the clinical course of multiple sclerosis (MS). Clinical phenotypes evolve across the lifespan, from a highly inflammatory course in the very young to a predominantly neurodegenerative phenotype in older patients. Thus, unique clinical considerations arise for the diagnosis and management of the two age extremes of pediatric and geriatric MS populations. This review covers epidemiology, diagnosis, and treatment strategies for these populations with nuanced discussions on therapeutic approaches to effectively care for patients living with MS at critical transition points during their lifespan.

Estrogen receptor beta in astrocytes modulates cognitive function in mid-age female mice

Menopause is associated with cognitive deficits and brain atrophy, but the brain region and cell-specific mechanisms are not fully understood. Here, we identify a sex hormone by age interaction whereby loss of ovarian hormones in female mice at midlife, but not young age, induced hippocampal-dependent cognitive impairment, dorsal hippocampal atrophy, and astrocyte and microglia activation with synaptic loss. Selective deletion of estrogen receptor beta (ERβ) in astrocytes, but not neurons, in gonadally intact female mice induced the same brain effects. RNA sequencing and pathway analyses of gene expression in hippocampal astrocytes from midlife female astrocyte-ERβ conditional knock out (cKO) mice revealed Gluconeogenesis I and Glycolysis I as the most differentially expressed pathways. Enolase 1 gene expression was increased in hippocampi from both astrocyte-ERβ cKO female mice at midlife and from postmenopausal women. Gain of function studies showed that ERβ ligand treatment of midlife female mice reversed dorsal hippocampal neuropathology.

Neuroprotection in Cerebral Cortex Induced by the Pregnancy Hormone Estriol

In multiple sclerosis (MS), demyelination occurs in the cerebral cortex, and cerebral cortex atrophy correlates with clinical disabilities. Treatments are needed in MS to induce remyelination. Pregnancy is protective in MS. Estriol is made by the fetoplacental unit, and maternal serum estriol levels temporally align with fetal myelination. Here, we determined the effect of estriol treatment on the cerebral cortex in the preclinical model of MS, experimental autoimmune encephalomyelitis (EAE). Estriol treatment initiated after disease onset decreased cerebral cortex atrophy. Neuropathology of the cerebral cortex showed increased cholesterol synthesis proteins in oligodendrocytes, more newly formed remyelinating oligodendrocytes, and increased myelin in estriol-treated EAE mice. Estriol treatment also decreased the loss of cortical layer V pyramidal neurons and their apical dendrites and preserved synapses. Together, estriol treatment after EAE onset reduced atrophy and was neuroprotective in the cerebral cortex.

Astrocyte-oligodendrocyte interaction regulates central nervous system regeneration

Failed regeneration of myelin around neuronal axons following central nervous system damage contributes to nerve dysfunction and clinical decline in various neurological conditions, for which there is an unmet therapeutic demand. Here, we show that interaction between glial cells - astrocytes and mature myelin-forming oligodendrocytes - is a determinant of remyelination. Using in vivo/ ex vivo/ in vitro rodent models, unbiased RNA sequencing, functional manipulation, and human brain lesion analyses, we discover that astrocytes support the survival of regenerating oligodendrocytes, via downregulation of the Nrf2 pathway associated with increased astrocytic cholesterol biosynthesis pathway activation. Remyelination fails following sustained astrocytic Nrf2 activation in focally-lesioned male mice yet is restored by either cholesterol biosynthesis/efflux stimulation, or Nrf2 inhibition using the existing therapeutic Luteolin. We identify that astrocyte-oligodendrocyte interaction regulates remyelination, and reveal a drug strategy for central nervous system regeneration centred on targeting this interaction.

Pregnancy Is Associated with Impaired Transcription of Human Endogenous Retroviruses and of TRIM28 and SETDB1, Particularly in Mothers Affected by Multiple Sclerosis

Accumulating evidence highlights the pathogenetic role of human endogenous retroviruses (HERVs) in eliciting and maintaining multiple sclerosis (MS). Epigenetic mechanisms, such as those regulated by TRIM 28 and SETDB1, are implicated in HERV activation and in neuroinflammatory disorders, including MS. Pregnancy markedly improves the course of MS, but no study explored the expressions of HERVs and of TRIM28 and SETDB1 during gestation. Using a polymerase chain reaction real-time Taqman amplification assay, we assessed and compared the transcriptional levels of pol genes of HERV-H, HERV-K, HERV-W; of env genes of Syncytin (SYN)1, SYN2, and multiple sclerosis associated retrovirus (MSRV); and of TRIM28 and SETDB1 in peripheral blood and placenta from 20 mothers affected by MS; from 27 healthy mothers, in cord blood from their neonates; and in blood from healthy women of child-bearing age. The HERV mRNA levels were significantly lower in pregnant than in nonpregnant women. Expressions of all HERVs were downregulated in the chorion and in the decidua basalis of MS mothers compared to healthy mothers. The former also showed lower mRNA levels of HERV-K-pol and of SYN1, SYN2, and MSRV in peripheral blood. Significantly lower expressions of TRIM28 and SETDB1 also emerged in pregnant vs. nonpregnant women and in blood, chorion, and decidua of mothers with MS vs. healthy mothers. In contrast, HERV and TRIM28/SETDB1 expressions were comparable between their neonates. These results show that gestation is characterized by impaired expressions of HERVs and TRIM28/SETDB1, particularly in mothers with MS. Given the beneficial effects of pregnancy on MS and the wealth of data suggesting the putative contribution of HERVs and epigenetic processes in the pathogenesis of the disease, our findings may further support innovative therapeutic interventions to block HERV activation and to control aberrant epigenetic pathways in MS-affected patients.

Sex Hormones as Key Modulators of the Immune Response in Multiple Sclerosis: A Review

BACKGROUND

A variety of autoimmune diseases, including MS, amplify sex-based physiological differences in immunological responsiveness. Female MS patients experience pathophysiological changes during reproductive phases (pregnancy and menopause). Sex hormones can act on immune cells, potentially enabling them to modify MS risk, activity, and progression, and to play a role in treatment.

METHODS

Scientific papers (published between 1998 and 2021) were selected through PubMed, Google Scholar, and Web of Science literature repositories. The search was limited to publications analyzing the hormonal profile of male and female MS patients during different life phases, in particular focusing on sex hormone treatment.

RESULTS

Both men and women with MS have lower testosterone levels compared to healthy controls. The levels of estrogens and progesterone increase during pregnancy and then rapidly decrease after delivery, possibly mediating an immune-stabilizing process. The literature examined herein evidences the neuroprotective effect of testosterone and estrogens in MS, supporting further examinations of their potential therapeutic uses.

CONCLUSIONS

A correlation has been identified between sex hormones and MS clinical activity. The combination of disease-modifying therapies with estrogen or estrogen plus a progestin receptor modulator promoting myelin repair might represent an important strategy for MS treatment in the future.

Sex bias and omission exists in Batten disease research: Systematic review of the use of animal disease models

Batten disease, also known as the neuronal ceroid lipofuscinoses (NCL), is a group of inherited neurodegenerative disorders mainly affecting children. NCL are characterised by seizures, loss of vision, and progressive motor and cognitive decline, and are the most common form of childhood dementia. At least one type of Batten disease and three types of mouse disease models show sex differences in their severity and progression. Scientific research has a recognised prevalent omission of female animals when using model organisms for basic and preclinical research. Sex bias and omission in research using animal models of Batten disease may affect understanding and treatment development. We conducted a systematic review of research publications since the first identification of NCL genes in 1995, identifying those using animal models. We found that <10 % of these papers considered sex as a biological variable. There was consistent omission of female model organisms in studies. This varied over the period but is improving; one third of papers considered sex as a biological variable in the last decade, and there is a noticeable increase in the last 5 years. The wide-ranging reasons for this published sex bias are discussed, including misunderstanding regarding oestrogen, impact on sample size, and the underrepresentation of female scientists. Their implications for Batten disease and future research are considered. Recommendations going forward support requirements by funders for consideration of sex in all stages of experimental design and implementation, and a role for publishers, families and others with a particular interest in Batten disease.

The underlying sex differences in neuroendocrine adaptations relevant to Myalgic Encephalomyelitis Chronic Fatigue Syndrome

INTRODUCTION

Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome (ME/CFS) is a complex multisystem disease characterised by severe and disabling new-onset symptoms of post-exertional malaise (PEM), fatigue, brain fog, and sleep dysfunction that lasts for at least six months. Accumulating evidence suggests that sex and endocrine events have a significant influence on symptom onset and moderation of ME/CFS, with female sex being one of the most consistent and credible predictive risk factors associated with diagnosis. Such sex differences suggest sex chromosomes and sex steroids may play a part in the development of the condition or moderation of symptoms, although this has yet to be explored in detail.

METHODS/AIMS

This narrative review outlines sex differences in ME/CFS in terms of vulnerability factors and clinical phenotype and explores the known sex differences in neuroendocrine systems affected in ME/CFS and how this may relate to disease risk, onset, pathophysiology, and potential treatment avenues.

CONCLUSIONS

There is clear evidence of a sex dimorphism with regards to prevalence (3:1 female preponderance), clinical phenotypes, and aetiological triggers prior to symptom onset of ME/CFS. Endocrinological events, particularly those throughout the female lifespan, are associated with ME/CFS and include reproductive menstrual cycle fluctuations, pregnancy, post-partum and perimenopause. Further, there is evidence for gonadal sex, adrenal stress and renal neuroendocrine systems as implicated in ME/CFS, including changes in estrogen, progesterone compounds, aldosterone, and cortisol levels, of which there are established sex differences. The broad effects of steroid hormones on the physiological systems may also speak to the diversity of ME/CFS symptomatology observed in patients. Further attention must be paid to sex, age, and steroid biology in ME/CFS.

Decreased neurofilament light chain levels in estriol-treated multiple sclerosis

Estrogens have neuroprotective actions depending on estrogen type, dose, and timing in both preclinical models and in women during health and disease. Serum neurofilament light chain is a putative biomarker of neurodegeneration in multiple sclerosis, aging, and other neurodegenerative diseases. Here, oral treatment with an estrogen unique to pregnancy (estriol) using an 8 mg dose to induce a mid‐pregnancy blood estriol level reduced serum neurofilament light chain in nonpregnant MS women at mean age of 37 years. This is consistent with estriol‐mediated protection from neuro‐axonal injury and supports the use of serum neurofilament light chain as a biomarker in MS.

Recommendations to Address the Unique Clinical and Psychological Needs of Transgender Persons Living With Multiple Sclerosis

BACKGROUND

People living with multiple sclerosis (MS) face challenges coping with chronic illnesses, and transgender (TGD) persons living with MS may experience additional unique challenges and barriers to care. Medical biases toward TGD people are widely reported, and best practices in TGD MS care have not been identified.

METHODS

A case report of a TGD person living with MS is reviewed that helped to identify and inform us regarding the unique aspects of their clinical and psychological care needs. We conducted a systematic review of the literature according to the standard methods in PubMed. The literature was reviewed and summarized for relevant topics related to the unique care needs of TGD persons living with MS, and proposed care recommendations were created.

RESULTS

We used the aforementioned case to identify and inform the special care needs and subsequently describe proposed recommendations to achieve inclusive comprehensive care of TGD persons with MS. The importance of providing an inclusive environment, comprehensive care, mental health screening, domestic violence screening, and case coordination are highlighted with the goal of providing best practice recommendations for the comprehensive inclusive care of TGD persons living with MS.

CONCLUSIONS

The lack of published guidance on the care of TGD persons living with MS and our informative case have led to the proposed recommendations for the care of TGD persons living with MS.

Reproductive history and progressive multiple sclerosis risk in women

Being a woman is one of the strongest risk factors for multiple sclerosis. The natural reproductive period from menarche to natural menopause corresponds to the active inflammatory disease period in multiple sclerosis. The fifth decade marks both the peri-menopausal transition in the reproductive aging and a transition from the relapsing-remitting to the progressive phase in multiple sclerosis. A short reproductive period with premature/early menopause and/or low number of pregnancies may be associated with an earlier onset of the progressive multiple sclerosis phase. A cross-sectional study of survey-based reproductive history in a multiple sclerosis clinical series enriched for patients with progressive disease, and a case–control study of multiple sclerosis and age/sex matched controls from a population-based cohort were conducted. Menarche age, number of complete/incomplete pregnancies, menopause type and menopause age were compared between 137 cases and 396 control females. Onset of relapsing-remitting phase of multiple sclerosis, progressive disease onset and reaching severe disability (expanded disability status scale 6) were studied as multiple sclerosis-related outcomes (n = 233). Menarche age was similar between multiple sclerosis and control females (P = 0.306). Females with multiple sclerosis had fewer full-term pregnancies than the controls (P < 0.001). Non-natural menopause was more common in multiple sclerosis (40.7%) than in controls (30.1%) (P = 0.030). Age at natural menopause was similar between multiple sclerosis (median, interquartile range: 50 years, 48–52) and controls (median, interquartile range: 51 years, 49–53) (P = 0.476). Nulliparous females had earlier age at progressive multiple sclerosis onset (mean ± standard deviation: 41.9 ± 12.5 years) than females with ≥1 full-term pregnancies (mean ± standard deviation: 47.1 ± 9.7 years) (P = 0.069) with a pregnancy-dose effect [para 0 (mean ± standard deviation: 41.9 ± 12.5 years), para 1–3 (mean ± standard deviation: 46.4 ± 9.2 years), para ≥4 (mean ± standard deviation: 52.6 ± 12.9 years) (P = 0.005)]. Menopause age was associated with progressive multiple sclerosis onset age (R² = 0.359, P < 0.001). Duration from onset of relapses to onset of progressive multiple sclerosis was shorter for females with premature/early menopause (n = 26; mean ± standard deviation: 12.9 ± 9.0 years) than for females with normal menopause age (n = 39; mean ± standard deviation: 17.8 ± 10.3 years) but was longer than for males (mean  ±standard deviation: 10.0 ± 9.4 years) (P = 0.005). There was a pregnancy-dose effect of age at expanded disability status scale 6 (para 0: 43.0 ± 13.2 years, para 1–3: 51.7 ± 11.3 years, para ≥4: 53.5 ± 4.9 years) (P = 0.013). Age at menopause was associated with age at expanded disability status scale 6 (R² = 0.229, P < 0.003). Premature/early menopause or nulliparity was associated with earlier onset of progressive multiple sclerosis with a ‘dose effect’ of pregnancies on delaying progressive multiple sclerosis and severe disability. Although causality remains uncertain, our results suggest a beneficial impact of oestrogen in delaying progressive multiple sclerosis. If confirmed in prospective studies, our findings have implications for counselling women with multiple sclerosis about pregnancy, surgical menopause and menopausal hormone therapy.

Pharmacotherapy in multiple sclerosis-induced cognitive impairment: A systematic review and meta-analysis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) commonly complicated by cognitive impairment. Unfortunately, no medical therapy has been proved to improve cognitive problems in these patients. This meta-analysis investigated the effectiveness of different categories of drugs on the minimal assessment of cognitive function in MS (MACFIMS)-related tasks outcome in MS patients. To this end, a systematic evaluation was conducted using PubMed, Google Scholar, and Scopus databases. Among a total of 128 publications, 31 studies met our inclusion criteria, and 22 included in the meta-analysis. We found that symbol digit modalities test (SDMT), paced auditory serial addition test (PASAT), controlled oral word association test (COWAT), and California verbal learning test (CVLT) were the most frequently reported tasks in included studies. The frequently reported drugs were classified into five main groups of acetylcholine esterase inhibitors, CNS stimulants, fampridine, herbal remedies, and miscellaneous. Overall heterogeneity of the studies was modest. The treatments did not affect cognitive function in any of the tasks (p>0.05). However, in subgroup analysis, we found significant improvement in SDMT task outecomes after treatment by fampridine (0.283 SMD, 95%CI, 0.015 to 0.550, p = 0.039, I2=11.7%). Our meta-analysis highlighted that the currently proposed therapeutic agents had no beneficial effects on the alleviation of MS-induced cognitive impairment.

Sex differences in brain atrophy in multiple sclerosis

BACKGROUND

Women are more susceptible to multiple sclerosis (MS) than men by a ratio of approximately 3:1. However, being male is a risk factor for worse disability progression. Inflammatory genes have been linked to susceptibility, while neurodegeneration underlies disability progression. Thus, there appears to be a differential effect of sex on inflammation versus neurodegeneration. Further, gray matter (GM) atrophy is not uniform across the brain in MS, but instead shows regional variation. Here, we study sex differences in neurodegeneration by comparing regional GM atrophy in a cohort of men and women with MS versus their respective age- and sex-matched healthy controls.

METHODS

Voxel-based morphometry (VBM), deep GM substructure volumetry, and cortical thinning were used to examine regional GM atrophy.

RESULTS

VBM analysis showed deep GM atrophy in the thalamic area in both men and women with MS, whereas men had additional atrophy in the putamen as well as in localized cortical regions. Volumetry confirmed deep GM loss, while localized cortical thinning confirmed GM loss in the cerebral cortex. Further, MS males exhibited worse performance on the 9-hole peg test (9HPT) than MS females. We observed a strong correlation between thalamic volume and 9HPT performance in MS males, but not in MS females.

CONCLUSION

More regional GM atrophy was observed in men with MS than women with MS, consistent with previous observations that male sex is a risk factor for worse disease progression.

Sex effects across the lifespan in women with multiple sclerosis

Multiple sclerosis (MS) is an autoimmune inflammatory demyelinating central nervous system disorder that is more common in women, with onset often during reproductive years. The female:male sex ratio of MS rose in several regions over the last century, suggesting a possible sex by environmental interaction increasing MS risk in women. Since many with MS are in their childbearing years, family planning, including contraceptive and disease-modifying therapy (DMT) counselling, are important aspects of MS care in women. While some DMTs are likely harmful to the developing fetus, others can be used shortly before or until pregnancy is confirmed. Overall, pregnancy decreases risk of MS relapses, whereas relapse risk may increase postpartum, although pregnancy does not appear to be harmful for long-term prognosis of MS. However, ovarian aging may contribute to disability progression in women with MS. Here, we review sex effects across the lifespan in women with MS, including the effect of sex on MS susceptibility, effects of pregnancy on MS disease activity, and management strategies around pregnancy, including risks associated with DMT use before and during pregnancy, and while breastfeeding. We also review reproductive aging and sexual dysfunction in women with MS.

Pregnancy, postpartum and parity: Resilience and vulnerability in brain health and disease

Risk and resilience in brain health and disease can be influenced by a variety of factors. While there is a growing appreciation to consider sex as one of these factors, far less attention has been paid to sex-specific variables that may differentially impact females such as pregnancy and reproductive history. In this review, we focus on nervous system disorders which show a female bias and for which there is data from basic research and clinical studies pointing to modification in disease risk and progression during pregnancy, postpartum and/or as a result of parity: multiple sclerosis (MS), depression, stroke, and Alzheimer's disease (AD). In doing so, we join others (Shors, 2016; Galea et al., 2018a) in aiming to illustrate the importance of looking beyond sex in neuroscience research.

The effect of sex on multiple sclerosis risk and disease progression

Sex differences in the incidence or severity of disease characterize many autoimmune and neurodegenerative diseases. Multiple sclerosis is a complex disease with both autoimmune and neurodegenerative aspects and is characterized by sex differences in susceptibility and progression. Research in the study sex differences is a way to capitalize on a known clinical observation, mechanistically disentangle it at the laboratory bench, then translate basic research findings back to the clinic as a novel treatment trial tailored to optimally benefit each sex. This "Bedside to Bench to Bedside" approach based on sex differences in MS will be reviewed here, first for disease susceptibility then for disability progression.

Drug repurposing for Alzheimer's disease based on transcriptional profiling of human iPSC-derived cortical neurons

Alzheimer's disease is a complex disorder encompassing multiple pathological features with associated genetic and molecular culprits. However, target-based therapeutic strategies have so far proved ineffective. The aim of this study is to develop a methodology harnessing the transcriptional changes associated with Alzheimer's disease to develop a high content quantitative disease phenotype that can be used to repurpose existing drugs. Firstly, the Alzheimer's disease gene expression landscape covering severe disease stage, early pathology progression, cognitive decline and animal models of the disease has been defined and used to select a set of 153 drugs tending to oppose disease-associated changes in the context of immortalised human cancer cell lines. The selected compounds have then been assayed in the more biologically relevant setting of iPSC-derived cortical neuron cultures. It is shown that 51 of the drugs drive expression changes consistently opposite to those seen in Alzheimer's disease. It is hoped that the iPSC profiles will serve as a useful resource for drug repositioning within the context of neurodegenerative disease and potentially aid in generating novel multi-targeted therapeutic strategies.

Estriol-mediated neuroprotection in multiple sclerosis localized by voxel-based morphometry

INTRODUCTION

Progressive gray matter (GM) atrophy is a hallmark of multiple sclerosis (MS). Cognitive impairment has been observed in 40%-70% of MS patients and has been linked to GM atrophy. In a phase 2 trial of estriol treatment in women with relapsing-remitting MS (RRMS), higher estriol levels correlated with greater improvement on the paced auditory serial addition test (PASAT) and imaging revealed sparing of localized GM in estriol-treated compared to placebo-treated patients. To better understand the significance of this GM sparing, the current study explored the relationships between the GM sparing and traditional MRI measures and clinical outcomes.

METHODS

Sixty-two estriol- and forty-nine placebo-treated RRMS patients underwent clinical evaluations and brain MRI. Voxel-based morphometry (VBM) was used to evaluate voxelwise GM sparing from high-resolution T1-weighted scans.

RESULTS

A region of treatment-induced sparing (TIS) was defined as the areas where GM was spared in estriol- as compared to placebo-treated groups, localized primarily within the frontal and parietal cortices. We observed that TIS volume was directly correlated with improvement on the PASAT. Next, a longitudinal cognitive disability-specific atlas (DSA) was defined by correlating voxelwise GM volumes with PASAT scores, that is, areas where less GM correlated with less improvement in PASAT scores. Finally, overlap between the TIS and the longitudinal cognitive DSA revealed a specific region of cortical GM that was preserved in estriol-treated subjects that was associated with better performance on the PASAT.

CONCLUSIONS

Discovery of this region of overlap was biology driven, not based on an a priori structure of interest. It included the medial frontal cortex, an area previously implicated in problem solving and attention. These findings indicate that localized GM sparing during estriol treatment was associated with improvement in cognitive testing, suggesting a clinically relevant, disability-specific biomarker for clinical trials of candidate neuroprotective treatments in MS.