Correlations between hippocampal functional connectivity,structural changes,and clinical data in patients with relapsing-remitting multiple sclerosis:a case-control study using multimodal magnetic resonance imaging

Multiple sclerosis is associated with structural and functional brain alterations leading to cognitive impairments across multiple domains including attention,memory,and the speed of information processing.The hippocampus,which is a brain important structure involved in memory,undergoes microstructural changes in the early stage of multiple sclerosis.In this study,we analyzed hippocampal function and structure in patients with relapsing-remitting multiple sclerosis and explored correlations between the functional connectivity of the hippocampus to the whole brain,changes in local brain function and microstructure,and cognitive function at rest.We retrospectively analyzed data from 20 relapsing-remitting multiple sclerosis patients admitted to the Department of Neurology at the China-Japan Union Hospital of Jilin University,China,from April 2015 to November 2019.Sixteen healthy volunteers were recruited as the healthy control group.All participants were evaluated using a scale of extended disability status and the Montreal cognitive assessment within 1 week before and after head diffusion tensor imaging and functional magnetic resonance imaging.Compared with the healthy control group,the patients with relapsing-remitting multiple sclerosis had lower Montreal cognitive assessment scores and regions of simultaneously enhanced and attenuated whole-brain functional connectivity and local functional connectivity in the bilateral hippocampus.Hippocampal diffusion tensor imaging data showed that,compared with the healthy control group,patients with relapsing-remitting multiple sclerosis had lower hippocampal fractional anisotropy values and higher mean diffusivity values,suggesting abnormal hippocampal structure.The left hippocampus whole-brain functional connectivity was negatively correlated with the Montreal cognitive assessment score(r=-0.698,P=0.025),and whole-brain functional connectivity of the right hippocampus was negatively correlated with extended disability status scale score(r=-0.649,P=0.042).The mean diffusivity value of the left hippocampus was negatively correlated with the Montreal cognitive assessment score(r=-0.729,P=0.017)and positively correlated with the extended disability status scale score(r=0.653,P=0.041).The right hippocampal mean diffusivity value was positively correlated with the extended disability status scale score(r=0.684,P=0.029).These data suggest that the functional connectivity and presence of structural abnormalities in the hippocampus in patients with relapse-remission multiple sclerosis are correlated with the degree of cognitive function and extent of disability.This study was approved by the Ethics Committee of China-Japan Union Hospital of Jilin University,China(approval No.201702202)on February 22,2017.

Regional gray matter atrophy and neuropsychologcal problems in relapsing-remitting multiple sclerosis

In multiple sclerosis, gray matter atrophy is extensive, and cognitive deficits and mood disorders are frequently encountered. It has been conjectured that focal atrophy is associated with emotional decline. However, conventional MRI has revealed that the pathological characteristics cannot fully account for the mood disorders. Moreover, there is no correlation between cognitive disorders and MRI results in clinically isolated syndromes or in cases of definite multiple sclerosis. In this casecontrol study, voxel-based morphometric analysis was performed on 11 subjects with relapsing-remitting multiple sclerosis, and the results show that these patients exhibit gray matter atrophy. Moreover, the gray matter atrophy in the superior and middle gyri of the right frontal lobe in patients with multiple sclerosis was correlated with scores from the Hamilton Anxiety Rating Scale. The scores obtained with the Repeatable Battery for the Assessment of Neuropsychological Status were associated with gray matter atrophy in the middle gyrus of the left frontal lobe, the superior and middle gyrus of the right frontal lobe, the middle gyrus of the left cingulate, the superior and middle gyri of the left frontal lobe, and the triangular area of the left frontal lobe. However, there was no statistical significance. These findings suggest that the cingulate and frontal cortices of the dominant hemisphere are the most severely atrophic regions of the brain, and this atrophy is correlated with cognitive decline and emotional abnormalities.

A network-based cognitive training induces cognitive improvements and neuroplastic changes in patients with relapsing-remitting multiple sclerosis:an exploratory case-control study

Cognitive impairments are commonly observed in patients with multiple sclerosis and are associated with lower levels of quality of life.No consensus has been reached on how to tackle effectively cognitive decline in this clinical population non-pharmacologically.This exploratory case-control study aims to investigate the effectiveness of a hypothesis-based cognitive training designed to target multiple domains by promoting the synchronous co-activation of different brain areas and thereby improve cognition and induce changes in functional connectivity in patients with relapsing-remitting multiple sclerosis.Forty-five patients(36 females and 9 males,mean age 44.62±8.80 years)with clinically stable relapsing-remitting multiple sclerosis were assigned to either a standard cognitive training or to control groups(sham training and nonactive control).The standard training included twenty sessions of computerized exercises involving various cognitive functions supported by distinct brain networks.The sham training was a modified version of the standard training that comprised the same exercises and number of sessions but with increased processing speed load.The non-active control group received no cognitive training.All patients underwent comprehensive neuropsychological and magnetic resonance imaging assessments at baseline and after 5 weeks.Cognitive and resting-state magnetic resonance imaging data were analyzed using repeated measures models.At reassessment,the standard training group showed significant cognitive improvements compared to both control groups in memory tasks not specifically targeted by the training:the Buschke Selective Reminding Test and the Semantic Fluency test.The standard training group showed reductions in functional connectivity of the salience network,in the anterior cingulate cortex,associated with improvements on the Buschke Selective Reminding Test.No changes were observed in the sham training group.These findings suggest that multi-domain training that stimulates multiple brain areas synchronously may improve cognition in people with relapsing-remitting multiple sclerosis if sufficient time to process training material is allowed.The associated reduction in functional connectivity of the salience network suggests that training-induced neuroplastic functional reorganization may be the mechanism supporting performance gains.This study was approved by the Regional Ethics Committee of Yorkshire and Humber(approval No.12/YH/0474)on November 20,2013.

Association between rs1800795 (-174 G/C) Polymorphism in the Promoter of <i>IL</i>6 Gene and Risk of Relapsing-Remitting Multiple Sclerosis (RRMS) in Isfahan Population

Multiple sclerosis (MS) is an inflammatory demyelinating disease of central nervous system (CNS) that mostly affects young adults. The etiology of MS includes both genetic and environmental factors. A single nucleotide polymorphism (SNP) linked with autoimmune disorders predisposition, identified by Genome-Wide Association Study (GWAS) among genes which immunologically related are considerably over signified. The goal of the current study is investigation of the association between rs1800795 (-174 G/C) polymorphism in the promoter of IL6 gene variant with the risk of RRMS in a subset of Iranian population. In this case-control study, 110 healthy subjects and 110 patients with RRMS were included. DNA was extracted from blood samples and polymerase chain reaction (PCR) was used to amplify the fragment of interest contain rs1800795 SNP, restriction fragment length polymorphism (RFLP) method was performed for genotyping of the DNA samples with a specific restriction enzyme (NlaIII). SPSS for Windows software (version 18.0;SPSS, Chicago, IL) was used for statistical analysis. No significant differences were found between RRMS patients and healthy controls with respect to the distribution of the cytokine gene polymorphism investigated. Odds ratio adjusted for age, sex, and blood groups (except A blood group) has displayed similar outcomes. These results indicate that the rs1800795 SNP is not a susceptibility gene variant for development of RRMS in the Isfahan population. Further studies using new data on complex transcriptional interactions between IL-6 polymorphic sites are necessary to determine IL-6 haplotype influence on susceptibility to RRMS.

Intrathecal IgG synthesis in relapsing-remitting multiple sclerosis (MS) is decreased by natural human alpha interferon

Intrathecal IgG synthesis (IT IgG Syn) is an established biomarker used for the diagnosis of multiple sclerosis (MS). Earlier studies used this biomarker to assess the impact of 2 different synthetic forms of interferon alpha (IFN-α) in chronic progressive MS. Unexpectedly, IT IgG synthesis was increased by this treatment. For the first time, we have assessed this parameter in relapsing-remitting patients to measure the impact of natural IFN-α treatment in a doseranging study in six dosage groups (5, 10, 15, 20, 25, & 30 MIU). We have found that IFN-α normalized IT IgG Synthesis at 12 weeks treatment for all dosage groups. Two weeks after stopping IFN-α results rose slightly. At 52 weeks, 28 weeks after stopping IFN-a results revealed cessation of IT IgG Synthesis in half of the patients (15, 20, 25 MIU weekly). These results reflect different outcomes for relapsing-remitting patients vs. chronic progressive patients. They may, however, reflect differences in the biological properties of the interferon products used. An optimal range of dosage with natural human IFN-α dosage for MS is suggested by the results.

Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies

Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.

Gut flora in multiple sclerosis:implications for pathogenesis and treatment

Multiple sclerosis is an inflammatory disorder chara cterized by inflammation,demyelination,and neurodegeneration in the central nervous system.Although current first-line therapies can help manage symptoms and slow down disease progression,there is no cure for multiple sclerosis.The gut-brain axis refers to complex communications between the gut flo ra and the immune,nervous,and endocrine systems,which bridges the functions of the gut and the brain.Disruptions in the gut flora,termed dys biosis,can lead to systemic inflammation,leaky gut syndrome,and increased susceptibility to infections.The pathogenesis of multiple sclerosis involves a combination of genetic and environmental factors,and gut flora may play a pivotal role in regulating immune responses related to multiple scle rosis.To develop more effective therapies for multiple scle rosis,we should further uncover the disease processes involved in multiple sclerosis and gain a better understanding of the gut-brain axis.This review provides an overview of the role of the gut flora in multiple scle rosis.

Physical exercise and synaptic protection in human and pre-clinical models of multiple sclerosis

In multiple sclerosis,only immunomodulato ry and immunosuppressive drugs are recognized as disease-modifying therapies.Howeve r,in recent years,several data from pre-clinical and clinical studies suggested a possible role of physical exe rcise as disease-modifying therapy in multiple sclerosis.Current evidence is sparse and often conflicting,and the mechanisms underlying the neuroprotective and antinflammatory role of exercise in multiple sclerosis have not been fully elucidated.Data,mainly derived from pre-clinical studies,suggest that exe rcise could enhance longterm potentiation and thus neuroplasticity,could reduce neuroinflammation and synaptopathy,and dampen astrogliosis and microgliosis.In humans,most trials focused on direct clinical and MRI outcomes,as investigating synaptic,neuroinflammato ry,and pathological changes is not straightfo rward compared to animal models.The present review analyzed current evidence and limitations in research concerning the potential disease-modifying therapy effects of exercise in multiple sclerosis in animal models and human studies.

Examination of the Effective Factors on the Multiple Sclerosis Diseases

This study was an attempt to examine the effective factors of the Multiple Sclerosis diseases. The participants of the study were selected from among a total number of 45 men and women who were treated in a health center in Azarbayegan and Damavand in Iran. In order to study, the researchers applied various procedures to collect the data of the study. The participants were interviewed and filled out the questionnaires. After categorizing and classifying the collected information and data, it was processed and analyzed and the results are found. To test the research questions, a one-sample T-test was used to analyze the data. The role of hypo vitamin D as a possible risk factor for multiple sclerosis was reviewed. First, it was emphasized that hypo vitamin could be only one of the risk factors for multiple sclerosis and that numerous other environmental and genetic risk factors appear to interact and combine to trigger the disease. The main aim of this study was to examine the effective factors of Multiple Sclerosis diseases. The methodology of this research was to test the research questions;one-sample T-test was used to analyze the data. The findings of this study revealed that the factors of gender, cold weather, vitamin D deficiency, and age (between 30 - 59) were effective on the Multiple Sclerosis diseases.

Immunologic pathogenesis of multiple sclerosis

Multiple sclerosis （MS） is an autoimmune disease. The etiology and pathogenesis of MS remain unclear. At present, there are substantial evidences to support the hypothesis that genetics plays a crucial role. The people who have genetic predisposing genes easily develop immune-mediated disorder, probably in conjunction with environmental factors. The aim of this review is to describe recent observations regarding the immunologic pathogenesis of MS.

Abnormalcortical thickness in relapsing-remitting multiple sclerosis,correlations with cognition impairment,and effect of modified Bushenyisui decoction(补肾益髓汤)on cognitive function of multiple sclerosis

OBJECTIVE:To investigate the changes of subcortical gray matter volume and cortical thickness,andexplorethe correlations between regional abnormalities of cortical thickness and cognitive impairment and the effect of modified Bushenyisui decoction(补肾益髓汤,BSYSD)on the cognitive function of multiple sclerosis(MS).METHODS:This prospective study was approved by the institutional review board.92 subjects were recruited,including 46 relapsing-remitting multiple sclerosis(RRMS)patients and 46 healthy controls(HC).Of the 46 patients,22 patients experienced the treatment of BSYSD for half a year.A conventional three-dimensional T1-weighted sequence were acquired for all participants on a 3.0 tesla magnetic resonance system.Basic information,detailed cognitive scales Montreal Cognitive Assessment(MoCA),symbol digit modalities test(SDMT),immediate memory,delayed recall,and long-term recognition were evaluated.Subcortical gray matter volume and cortical thickness weremeasured by FreeSurfer.The correlations between cortical thickness which MS patients showed reduced with respect to HC and cognitive scales wereanalyzed by Pearson correlation in RRMS patients.The influence of modified BSYSD on MS patients'cognition was analyzed by paired T Test.RESULTS:MoCA,immediate memory,delayed recall,and long-term delayed recognition in RRMS were significantly decreased than those of HC.Gray matter atrophy measured by FreeSurfer showed mainly in thalamus and hippocampus of RRMS patients.Compared with HC,the cortical thickness of several regions in frontal lobe,parietal lobe,temporal lobe,hippocampal,cingulate gyrus,and fusiform gyrus of RRMS patients were decreased with significant difference.The regions of cortical thickness thinning related to MoCA,immediate memory,delayed recall,and long-term delayed recognition were temporal lobe and fusiform gyrus.Modified BSYSD could improve MoCA,SDMT,immediate memory,delayed recall,and long-term delayed recognition of MS patients,and it could promote the recovery of cognitive function in MS patients.CONCLUSIONS:Gray matter atrophy and cortical thickness thinning were validated in RRMS.Cortical thickness thinning of temporal lobe and fusiform gyrus strongly related to cognitive deficits in RRMS.The modified BSYSD could promote the recovery of cognitive function in MS.

Role of nuclear factor κB in multiple sclerosis and experimental autoimmune encephalomyelitis

The transcription factor nuclear factor κB（NF-κB） plays major roles in inflammatory diseases through regulation of inflammation and cell viability.Multiple sclerosis（MS） is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system（CNS）.It has been shown that NF-κB is activated in multiple cell types in the CNS of MS patients,including T cells,microglia/macrophages,astrocytes,oligodendrocytes,and neurons.Interestingly,data from animal model studies,particularly studies of experimental autoimmune encephalomyelitis,have suggested that NF-κB activation in these individual cell types has distinct effects on the development of MS.In this review,we will cover the current literature on NF-κB and the evidence for its role in the development of MS and its animal model experimental autoimmune encephalomyelitis.

MicroRNAs as disease progression biomarkers and therapeutic targets in experimental autoimmune encephalomyelitis model of multiple sclerosis

Multiple sclerosis is an autoimmune neurodegenerative disease of the central nervous system characterized by pronounced inflammatory infiltrates entering the brain,spinal cord and optic nerve leading to demyelination.Focal demyelination is associated with relapsing-remitting multiple sclerosis,while progressive forms of the disease show axonal degeneration and neuronal loss.The tests currently used in the clinical diagnosis and management of multiple sclerosis have limitations due to specificity and sensitivity.MicroRNAs(miRNAs)are dysregulated in many diseases and disorders including demyelinating and neuroinflammatory diseases.A review of recent studies with the experimental autoimmune encephalomyelitis animal model(mostly female mice 6–12 weeks of age)has confirmed miRNAs as biomarkers of experimental autoimmune encephalomyelitis disease and importantly at the pre-onset(asymptomatic)stage when assessed in blood plasma and urine exosomes,and spinal cord tissue.The expression of certain miRNAs was also dysregulated at the onset and peak of disease in blood plasma and urine exosomes,brain and spinal cord tissue,and at the post-peak(chronic)stage of experimental autoimmune encephalomyelitis disease in spinal cord tissue.Therapies using miRNA mimics or inhibitors were found to delay the induction and alleviate the severity of experimental autoimmune encephalomyelitis disease.Interestingly,experimental autoimmune encephalomyelitis disease severity was reduced by overexpression of miR-146a,miR-23b,miR-497,miR-26a,and miR-20b,or by suppression of miR-182,miR-181c,miR-223,miR-155,and miR-873.Further studies are warranted on determining more fully miRNA profiles in blood plasma and urine exosomes of experimental autoimmune encephalomyelitis animals since they could serve as biomarkers of asymptomatic multiple sclerosis and disease course.Additionally,studies should be performed with male mice of a similar age,and with aged male and female mice.

Neurogenic bowel dysfunction in patients with spinal cord injury, myelomeningocele, multiple sclerosis and Parkinson’s disease

Exciting new features have been described concerning neurogenic bowel dysfunction,including interactions between the central nervous system,the enteric nervous system,axonal injury,neuronal loss,neurotransmission of noxious and non-noxious stimuli,and the fields of gastroenterology and neurology.Patients with spinal cord injury,myelomeningocele,multiple sclerosis and Parkinson's disease present with serious upper and lower bowel dysfunctions characterized by constipation,incontinence,gastrointestinal motor dysfunction and altered visceral sensitivity.Spinal cord injury is associated with severe autonomic dysfunction,and bowel dysfunction is a major physical and psychological burden for these patients.An adult myelomeningocele patient commonly has multiple problems reflecting the multisystemic nature of the disease.Multiple sclerosis is a neurodegenerative disorder in which axonal injury,neuronal loss,and atrophy of the central nervous system can lead to permanent neurological damage and clinical disability.Parkinson's disease is a multisystem disorder involving dopaminergic,noradrenergic,serotoninergic and cholinergic systems,characterizedby motor and non-motor symptoms.Parkinson's disease affects several neuronal structures outside the substantia nigra,among which is the enteric nervous system.Recent reports have shown that the lesions in the enteric nervous system occur in very early stages of the disease,even before the involvement of the central nervous system.This has led to the postulation that the enteric nervous system could be critical in the pathophysiology of Parkinson's disease,as it could represent the point of entry for a putative environmental factor to initiate the pathological process.This review covers the data related to the etiology,epidemiology,clinical expression,pathophysiology,genetic aspects,gastrointestinal motor dysfunction,visceral sensitivity,management,prevention and prognosis of neurogenic bowel dysfunction patients with these neurological diseases.Embryological,morphological and experimental studies on animal models and humans are also taken into account.

The contribution of oligodendrocytes and oligodendrocyte progenitor cells to central nervous system repair in multiple sclerosis： perspectives for remyelination therapeutic strategies

Oligodencrocytes（OLs） are the main glial cells of the central nervous system involved in myelination of axons. In multiple sclerosis（MS）, there is an imbalance between demyelination and remyelination processes, the last one performed by oligodendrocyte progenitor cells（OPCs） and OLs, resulting into a permanent demyelination, axonal damage and neuronal loss. In MS lesions, astrocytes and microglias play an important part in permeabilization of blood-brain barrier and initiation of OPCs proliferation. Migration and differentiation of OPCs are influenced by various factors and the process is finalized by insufficient acummulation of OLs into the MS lesion. In relation to all these processes, the author will discuss the potential targets for remyelination strategies.

Protective effects of pharmacological therapies in animal models of multiple sclerosis: a review of studies 2014–2019

Multiple sclerosis(MS)is an inflammatory demyelinating disease of the central nervous system.The disability caused by inflammatory demyelination clinically dominates the early stages of relapsing-remitting MS and is reversible.Once there is considerable loss of axons,MS patients enter a secondary progressive stage.Disease-modifying drugs currently in use for MS suppress the immune system and reduce relapse rates but are not effective in the progressive stage.Various animal models of MS(mostly mouse and rat)have been established and proved useful in studying the disease process and response to therapy.The experimental autoimmune encephalomyelitis animal studies reviewed here showed that a chronic progressive disease can be induced by immunization with appropriate amounts of myelin oligodendrocyte glycoprotein together with mycobacterium tuberculosis and pertussis toxin in Freund's adjuvant.The clinical manifestations of autoimmune encephalomyelitis disease were prevented or reduced by treatment with certain pharmacological agents given prior to,at,or after peak disease,and the agents had protective effects as shown by inhibiting demyelination and damage to neurons,axons and oligodendrocytes.In the cuprizone-induced toxicity animal studies,the pharmacological agents tested were able to promote remyelination and increase the number of oligodendrocytes when administered therapeutically or prophylactically.A monoclonal IgM antibody protected axons in the spinal cord and preserved motor function in animals inoculated with Theiler's murine encephalomyelitis virus.In all these studies the pharmacological agents were administered singly.A combination therapy may be more effective,especially using agents that target neuroinflammation and neurodegeneration,as they may exert synergistic actions.

Microglia depletion as a therapeutic strategy:friend or foe in multiple sclerosis models?

M ultiple sclerosis is a chro nic central nervous system demyelinating disease whose onset and progression are driven by a combination of immune dysregulation,genetic predisposition,and environmental fa ctors.The activation of microglia and astrocytes is a key player in multiple sclerosis immunopathology,playing specific roles associated with anatomical location and phase of the disease and controlling demyelination and neurodegeneration.Even though reactive mic roglia can damage tissue and heighten deleterious effects and neurodegeneration,activated microglia also perform neuroprotective functions such as debris phagocytosis and growth fa ctor secretion.Astrocytes can be activated into pro-inflammato ry phenotype A1 through a mechanism mediated by activated neuroinflammatory microglia,which could also mediate neurodegeneration.This A1 phenotype inhibits oligodendrocyte prolife ration and differe ntiation and is toxic to both oligodendrocytes and neurons.Howeve r,astroglial activation into phenotype A2 may also take place in response to neurodegeneration and as a protective mechanism.A variety of animal models mimicking specific multiple sclerosis features and the associated pathophysiological processes have helped establish the cascades of events that lead to the initiation,progression,and resolution of the disease.The colonystimulating facto r-1 receptor is expressed by myeloid lineage cells such as peripheral monocytes and macrophages and central nervous system microglia.Importantly,as microglia development and survival critically rely on colony-stimulating factor-1 receptor signaling,colony-stimulating factor-1 receptor inhibition can almost completely eliminate microglia from the brain.In this context,the present review discusses the impact of microglial depletion through colo ny-stimulating factor-1 receptor inhibition on demyelination,neurodegeneration,astroglial activation,and behavior in different multiple sclerosis models,highlighting the diversity of microglial effects on the progression of demyelinating diseases and the strengths and weaknesses of microglial modulation in therapy design.

CDP-choline to promote remyelination in multiple sclerosis:the need for a clinical trial

Multiple sclerosis is a multifactorial chronic inflammatory disease of the central nervous system that leads to demyelination and neuronal cell death,resulting in functional disability.Remyelination is the natural repair process of demyelination,but it is often incomplete or fails in multiple sclerosis.Available therapies reduce the inflammatory state and prevent clinical relapses.However,therapeutic approaches to increase myelin repair in humans are not yet available.The substance cytidine-5′-diphosphocholine,CDP-choline,is ubiquitously present in eukaryotic cells and plays a crucial role in the synthesis of cellular phospholipids.Regenerative properties have been shown in various animal models of diseases of the central nervous system.We have already shown that the compound CDPcholine improves myelin regeneration in two animal models of multiple sclerosis.However,the results from the animal models have not yet been studied in patients with multiple sclerosis.In this review,we summarise the beneficial effects of CDP-choline on biolipid metabolism and turnover with regard to inflammatory and regenerative processes.We also explain changes in phospholipid and sphingolipid homeostasis in multiple sclerosis and suggest a possible therapeutic link to CDP-choline.

Cognitive impairment in multiple sclerosis: lessons from cerebrospinal fluid biomarkers

Cognitive impairment is a common clinical manifestation of multiple sclerosis,but its pathophysiology is not completely understood.White and grey matter injury together with synaptic dysfunction do play a role.The measurement of biomarkers in the cerebrospinal fluid and the study of their association with cognitive impairment may provide interesting in vivo evidence of the biological mechanisms underlying multiple sclerosis-related cognitive impairment.So far,only a few studies on this topic have been published,giving interesting results that deserve further investigation.Cerebrospinal fluid biomarkers of different pathophysiological mechanisms seem to reflect different neuropsychological patterns of cognitive deficits in multiple sclerosis.The aim of this review is to discuss the studies that have correlated cerebrospinal fluid markers of immune,glial and neuronal pathology with cognitive impairment in multiple sclerosis.Although preliminary,these findings suggest that cerebrospinal fluid biomarkers show some correlation with cognitive performance in multiple sclerosis,thus providing interesting insights into the mechanisms underlying the involvement of specific cognitive domains.

Correlation between white matter damage and gray matter lesions in multiple sclerosis patients

We observed the characteristics of white matter fibers and gray matter in multiple sclerosis patients, to identify changes in diffusion tensor imaging fractional anisotropy values following white matter fiber injury. We analyzed the correlation between fractional anisotropy values and changes in whole-brain gray matter volume. The participants included 20 patients with relapsing-remitting multiple sclerosis and 20 healthy volunteers as controls. All subjects underwent head magnetic resonance imaging and diffusion tensor imaging. Our results revealed that fractional anisotropy values decreased and gray matter volumes were reduced in the genu and splenium of corpus callosum, left anterior thalamic radiation, hippocampus, uncinate fasciculus, right corticospinal tract, bilateral cingulate gyri, and inferior longitudinal fasciculus in multiple sclerosis patients. Gray matter volumes were significantly different between the two groups in the right frontal lobe（superior frontal, middle frontal, precentral, and orbital gyri）, right parietal lobe（postcentral and inferior parietal gyri）, right temporal lobe（caudate nucleus）, right occipital lobe（middle occipital gyrus）, right insula, right parahippocampal gyrus, and left cingulate gyrus. The voxel sizes of atrophic gray matter positively correlated with fractional anisotropy values in white matter association fibers in the patient group. These findings suggest that white matter fiber bundles are extensively injured in multiple sclerosis patients. The main areas of gray matter atrophy in multiple sclerosis are the frontal lobe, parietal lobe, caudate nucleus, parahippocampal gyrus, and cingulate gyrus. Gray matter atrophy is strongly associated with white matter injury in multiple sclerosis patients, particularly with injury to association fibers.