Impact of Exercise on Innate Immunity in Multiple Sclerosis Progression and Symptomatology

Comments on energy conservation treatments for MS-related fatigue and a new proposal

Psychological treatments of MS-related fatigue mostly depend on energy conservation programs. We argue that the evidence for energy conservation training is weak - in contrast to some reviews on this topic. The reasons for our concerns are the use of informed passive control groups allowing negative placebo effects, the lack of predefined primary outcome parameter, statistically rather than clinically significant effects, and the use of insensitive fatigue questionnaires. We propose to base psychological interventions not on a view of fatigue as a constant loss of mental energy but as a subjective representation ("feeling") of an inflammatory state, which draws away attentional capacity. This conceptualization allows to develop a three-step treatment approach: Getting short-term control on fatigue, extinction to reduce fatigue-related avoidance behavior, and a systematic increase of activities by pacing. Our proposal depends on the techniques, that can interrupt ongoing feelings of fatigue and can serve as a basis for extinction. We propose that Progressive Muscle Relaxation might be such a technique. The advantage of our model is that it shares similarities with well-established treatments for phobias and chronic pain and we discuss the shared set of assumptions. Hopefully, this will help to improve the treatment of fatigue in future.

Breaking boundaries: the transformative role of exercise in managing multiple sclerosis

Multiple sclerosis (MS) is a prevalent cause of physical disability in adults, with inflammation-induced demyelination and neurodegeneration contributing to its etiology. This comprehensive review explores the multifaceted benefits of exercise in managing MS, including improvements in aerobic capacity, balance, muscle strength, immune and hormonal functions and mood. Various exercise modalities, such as aerobic, resistance, flexibility, and balance training, are discussed, along with tailored protocols for MS patients. Recommended exercise strategies are: aerobic exercise: 2-3x/week; 10-30 minutes (40 %-60 % of maximum heart rate (HRmax), HIIT: 1x/week, five 30-90-second intervals at 90 %-100 % HRmax, Resistance training: 2-3x/week, 5-10 exercises; 1-3 sets for each exercise, 8-15 repetitions/set. The review also examines the impact of exercise on neuroplasticity, cardiovascular responses, cytokine modulation, stress hormone regulation, brain structure, and function and fatigue perception. Emphasizing the importance of exercise in enhancing the quality of life for individuals with MS, the review proposes exercise prescriptions and highlights the promising link between physical activity, brain health, and improved hormonal and immune status in MS patients. This review aims to inform future research and guide clinical practices for effective MS management.

Preventive exercise and physical rehabilitation promote long-term potentiation-like plasticity expression in patients with multiple sclerosis

BACKGROUND AND PURPOSE

Loss of long-term potentiation (LTP) expression has been associated with a worse disease course in relapsing-remitting multiple sclerosis (RR-MS) and represents a pathophysiological hallmark of progressive multiple sclerosis (PMS). Exercise and physical rehabilitation are the most prominent therapeutic approaches to promote synaptic plasticity. We aimed to explore whether physical exercise is able to improve the expression of LTP-like plasticity in patients with multiple sclerosis (MS).

METHODS

In 46 newly diagnosed RR-MS patients, we explored the impact of preventive exercise on LTP-like plasticity as assessed by intermittent theta-burst stimulation. Patients were divided into sedentary or active, based on physical activity performed during the 6 months prior to diagnosis. Furthermore, in 18 patients with PMS, we evaluated the impact of an 8-week inpatient neurorehabilitation program on clinical scores and LTP-like plasticity explored using paired associative stimulation (PAS). Synaptic plasticity expression was compared in patients and healthy subjects.

RESULTS

Reduced LTP expression was found in RR-MS patients compared with controls. Exercising RR-MS patients showed a greater amount of LTP expression compared with sedentary patients. In PMS patients, LTP expression was reduced compared with controls and increased after 8 weeks of rehabilitation. In this group of patients, LTP magnitude at baseline predicted the improvement in hand dexterity.

CONCLUSIONS

Both preventive exercise and physical rehabilitation may enhance the expression of LTP-like synaptic plasticity in MS, with potential beneficial effects on disability accumulation.

Performance Measures and Plasma Biomarker Levels in Patients with Multiple Sclerosis after 14 Days of Fampridine Treatment: An Explorative Study

Peripheral cytokine levels may serve as biomarkers for treatment response and disease monitoring in patients with multiple sclerosis (pwMS). The objectives were to assess changes in plasma biomarkers in PwMS after 14 days of fampridine treatment and to explore correlations between changes in performance measures and plasma biomarkers. We included 27 PwMS, 14 women and 13 men, aged 52.0 ± 11.6 years, with a disease duration of 17 ± 8.5 years, and an Expanded Disability Status Scale of 6 [IQR 5.0/6.5]. Gait and hand function were assessed using performance tests completed prior to fampridine and after 14 days of treatment. Venous blood was obtained, and chemiluminescence analysis conducted to assess plasma cytokines and neurodegenerative markers. All performance measures demonstrated improvements. Biomarkers showed decreased tumor necrosis factor (TNF) receptor-2 levels. Associations were found between change scores in (i) Six Spot Step Test and Interleukin (IL)-2, IL-8, and IL-17 levels; (ii) timed 25-foot walk and interferon-γ, IL-2, IL-8, TNF-α, and neurofilament light levels, and (iii) 12-Item Multiple Sclerosis Walking Scale and IL-17 levels. The associations may reflect increased MS-related inflammatory activity rather than a fampridine-induced response or that a higher level of inflammation induces a better response to fampridine.

Physical activity and risk of multiple sclerosis: A Mendelian randomization study

Multiple evidence from epidemiological studies has suggested association between physical activity and risk of multiple sclerosis (MS). However, the conclusion was still controversial between studies, and whether the association was causal or confounded is elusive. To evaluate the role of physical activity with different intensities in the risk of MS, we first estimated their genetic correlation, and then conducted two-sample and multivariable Mendelian randomization analyses based on summary statistics from previous large genome-wide association studies. A significant genetic correlation was identified between moderate physical activity and the risk of MS (genetic correlation: -0.15, SE=0.05, P=2.9E-03). Meanwhile, higher moderate physical activity was significantly associated with a reduced risk of MS (OR:0.87, 95% CI:0.80-0.96, P=3.45E-03). Such association was further verified using summary statistics from another study on overall physical activity (OR:0.36, 95% CI:0.17-0.76, P=6.82E-03). The results were robust under all sensitivity analyses. Current results suggested moderate physical activity could reduce the risk of MS. These findings help better understand the role of physical activity in MS, and provide some lifestyle recommendations for individuals susceptible to MS.

Fatigue is associated with physical inactivity in people with multiple sclerosis despite different environmental backgrounds: Merging and comparing cohorts from Turkey and Israel

BACKGROUND

Examining leisure-time physical activity in people with multiple sclerosis (PwMS) from different environmental backgrounds might increase understanding and awareness of inactivity in PwMS. Therefore, the study objective was twofold; to compare the level of physical activity in PwMS in Israel and Turkey and to examine the relationship between the level of physical activity with common disease-related symptoms and demographical characteristics of PwMS.

METHODS

Cross-sectional data collected by two centers were combined. The physical activity level was determined by the Godin Leisure-Time Exercise Questionnaire, and subsequently, classified into one of three subgroups: "active", "moderately active" and "insufficiently active". Logistic regressions determined the risks of insufficiently active PwMS, according to age, gender, body mass index, disability, impact of walking impairment, disease duration, type of MS and perceived fatigue. The analysis of variance test determined the differences between countries in terms of outcome variables.

RESULTS

The study comprised 458 patients from Israel and 575 from Turkey; 68.2% Turkish PwMS were classified as insufficiently active compared with 52.0% of Israeli PwMS. The percentage of insufficiently active PwMS was significantly higher in those categorized as fatigued compared to non-fatigued in the total cohort (72.4% vs. 51.9%, p<0.001) and in each country separately. Based on the regression analysis, fatigue was the main factor associated with the insufficiently physically active group; odds ratio=1.968.

CONCLUSION

PwMS with increased fatigue tend to participate in less leisure-time physical activities compared with the non-fatigued. This observation is supported by the merged data collected from two countries, Turkey and Israel, representing PwMS from different environmental backgrounds.

Running to save sight: The effects of exercise on retinal health and function

The benefits of exercise to human health have long been recognised. However, only in the past decade have researchers started to discover the molecular benefits that exercise confers, especially to the central nervous system (CNS). These discoveries include the magnitude of molecular messages that are communicated from skeletal muscle to the CNS. Despite these advances in understanding, very limited studies have been conducted to decipher the molecular benefits of exercise in retinal health and disease. Here, we review the latest work on the effects of exercise on the retina and discuss its effects on the wider CNS, with a focus on demonstrating the potential applicability and comparative molecular mechanisms that may be occurring in the retina. This review covers the key molecular pathways where exercise exerts its effects: oxidative stress and mitochondrial health; inflammation; protein aggregation; neuronal health; and tissue crosstalk via extracellular vesicles. Further research on the benefits of exercise to the retina and its molecular messages within extracellular vesicles is highly topical in this field.

Fitness Shifts the Balance of BDNF and IL-6 from Inflammation to Repair among People with Progressive Multiple Sclerosis

Physical sedentarism is linked to elevated levels of circulating cytokines, whereas exercise upregulates growth-promoting proteins such as brain-derived neurotrophic factor (BDNF). The shift towards a 'repair' phenotype could protect against neurodegeneration, especially in diseases such as multiple sclerosis (MS). We investigated whether having higher fitness or participating in an acute bout of maximal exercise would shift the balance of BDNF and interleukin-6 (IL-6) in serum samples of people with progressive MS (n = 14), compared to matched controls (n = 8). Participants performed a maximal graded exercise test on a recumbent stepper, and blood samples were collected at rest and after the test. We assessed walking speed, fatigue, and maximal oxygen consumption (V·O2max). People with MS achieved about 50% lower V·O2max (p = 0.003) than controls. At rest, there were no differences in BDNF between MS and controls; however, IL-6 was significantly higher in MS. Higher V·O2max was associated with a shift in BDNF/IL-6 ratio from inflammation to repair (R = 0.7, p = 0.001) when considering both groups together. In the MS group, greater ability to upregulate BDNF was associated with faster walking speed and lower vitality. We present evidence that higher fitness indicates a shift in the balance of blood biomarkers towards a repair phenotype in progressive MS.

Depression mediates the relationship between fatigue and mental health-related quality of life in multiple sclerosis

BACKGROUND

Fatigue is among the most prevalent symptoms for people with multiple sclerosis (pwMS) and is significantly detrimental to mental health-related (mental) quality of life (QoL). We examined the role of depression and physical activity as mediators in the fatigue-QoL relationship in pwMS.

METHODS

Using baseline cross-sectional data from an international cohort of 2,104 pwMS, characteristics of fatigue and mental QoL, measured by Fatigue Severity Scale and MSQOL-54 respectively, were assessed using linear and log-binomial regression. Structural Equation Models (SEM) were used to explore the mediating roles of depression and physical activity between fatigue and mental QoL.

RESULTS

The median mental QoL score was 71.9/100. The mean fatigue score was 41.5/63, with 65.6% participants having clinically significant fatigue. In the SEM evaluating depression as a mediator of the fatigue-QoL relationship, mental QoL was 14.72 points lower (95% CI: -16.43 -13.01, p<0.001) in participants with clinically significant fatigue, of which depression accounted for 53.0% (-7.80, 95% CI: -9.03 -6.57, p<0.001). In the SEM evaluating physical activity as a mediator of the fatigue-QoL relationship, mental QoL was 10.89 points lower (95% CI: -12.47, -9.32, p<0.001) in participants with clinically significant fatigue, of which the indirect effect via physical activity accounted for only 4.4% (-0.48, 95% CI: -0.81, -0.14, p=0.005).

CONCLUSION

Depression accounted for the majority of the fatigue-mental QoL relationship when modelled as a mediator, while physical activity had only a minor role. Our findings may inform the development of treatments for reducing the impacts of fatigue and improving mental QoL in pwMS.

Impact of Exercise on Immunometabolism in Multiple Sclerosis

Multiple Sclerosis (MS) is a chronic, autoimmune condition characterized by demyelinating lesions and axonal degradation. Even though the cause of MS is heterogeneous, it is known that peripheral immune invasion in the central nervous system (CNS) drives pathology at least in the most common form of MS, relapse-remitting MS (RRMS). The more progressive forms’ mechanisms of action remain more elusive yet an innate immune dysfunction combined with neurodegeneration are likely drivers. Recently, increasing studies have focused on the influence of metabolism in regulating immune cell function. In this regard, exercise has long been known to regulate metabolism, and has emerged as a promising therapy for management of autoimmune disorders. Hence, in this review, we inspect the role of key immunometabolic pathways specifically dysregulated in MS and highlight potential therapeutic benefits of exercise in modulating those pathways to harness an anti-inflammatory state. Finally, we touch upon current challenges and future directions for the field of exercise and immunometabolism in MS.

Pilates for rehabilitation in patients with multiple sclerosis: A systematic review of effects on cognition, health-related physical fitness, general symptoms and quality of life

OBJECTIVE

The aims of this systematic review is to analyze the effectiveness of Pilates intervention programs on cognitive function, health-related physical fitness, general symptoms, physical function, quality of life, and the impact Pilates can have on activities of daily living in Multiple Sclerosis (MS) patients. This review also aims to provide a synthesis of the most commonly used protocols regarding exercise parameters, such as periodicity and treatment duration.

DATA SOURCES

Systematic review of the literature was carried out following the PRISMA guidelines (PROSPERO no. CRD42017070004). A literature search was undertaken for studies that investigated the effects of Pilates training on MS patients, using databases included PubMed, Medline, Scopus and the Physiotherapy Evidence Database (PEDro) up to May 2018.

STUDY SELECTION

Three researchers independently reviewed the titles and abstract of each article to screen the papers in relation to the inclusion criteria.

DATA EXTRACTION

Data were extracted by three researchers independently. The eligible articles were read in full and their levels of evidence were evaluated using the PEDro scale.

DATA SYNTHESIS

Forty-two papers were found during the research phase. Duplicated (n = 23) or incomplete articles (n = 1) were excluded. Studies were also eliminated from the sample based on methodological approach (study design) quality assessment (n = 6). Twelve studies were ultimately selected and analyzed.

CONCLUSIONS

The majority of the studies analyzed showed positive results after Pilates training intervention and concluded that Pilates intervention is safe and effective for the treatment of dysfunction of balance, strength, quality of life, cognition, physical performance, walking and posture parameters on MS patients. The articles investigated in this review provide a scientific basis to support Pilates as an option for rehabilitation programs for MS patients.

Influence of combined functional resistance and endurance exercise over 12 weeks on matrix metalloproteinase-2 serum concentration in persons with relapsing-remitting multiple sclerosis - a community-based randomized controlled trial

BACKGROUND

The relevance of regular moderate to intense exercise for ameliorating psychomotor symptoms in persons with multiple sclerosis (pwMS) is becoming increasingly evident. Over the last two decades, emerging evidence from clinical studies and animal models indicate immune regulatory mechanisms in both periphery and the central nervous system that may underlie these beneficial effects. The integrity of the blood-brain barrier as the main structural interface between periphery and brain seems to play an important role in MS. Reducing the secretion of proteolytic matrix metalloproteinases (MMP), i.e. MMP-2, as disruptors of blood-brain barrier integrity could have profound implications for MS.

METHODS

In this two-armed randomized controlled trial 64 participants with relapsing-remitting MS (RRMS) (EDSS 0-4.0) will be allocated to either an intervention group or a passive wait list control group. The intervention group will perform 60 min of combined functional resistance and endurance exercises 3x per week over a period of 12 weeks in a community-based and publicly available setting. Changes in serum concentration of MMP-2 will be the primary outcome. Secondary outcomes are numbers of immune cell subsets, soluble (anti-) inflammatory factors, physical capacity, cognitive performance, physical activity behavior, gait performance, and patient-reported outcomes. All outcome measures will be assessed at baseline and after week 12 with an additional blood sampling before, during and immediately after a single training session in week 6.

DISCUSSION

To our knowledge, this will be the first RCT to investigate both the acute and chronic effects of a community-based intense functional resistance and endurance exercise regimen in persons with RRMS. Combining analysis of biological and cognitive or psychological outcomes may provide a better understanding of the MS-specific symptomology.

TRIAL REGISTRATION

DRKS00017091; 05th of April, 2019; International Clinical Trials Registry Platform.

Physical activity participation according to the pyramidal, sensory, and cerebellar functional systems in multiple sclerosis

The objective of the study was to examine the differences in physical activity participation with the pyramidal, cerebellar, and sensory functional systems in people with multiple sclerosis (PwMS). This cross-sectional study included 289 PwMS with a median EDSS of 2.0 (range 0-6.5) and a mean disease duration of 6.8 (SD = 8.4) years. The Godin leisure-time exercise questionnaire (GLTEQ) assessed physical activity participation. The sample was divided into seven groups according to the pyramidal, cerebellar, and sensory functional system scores derived from the EDSS data. Additionally, PwMS were divided into three physical activity subgroups (active, moderately active, and insufficiently active). Furthermore, PwMS were categorized into four levels of disability based on their global Expanded Disability Status Scale (EDSS) score [very mild (0-1.5), mild (2.0-3.5), moderate (4.0-5.5), and severe (6.0-6.5)]. In the physical activity subgroups, 159 (55.0%) were classified as insufficiently active, 59 (20.4%) as moderately active, and 71 (24.6%) as active. Pyramidal, cerebellar, and sensory impairments were demonstrated in 134 (46.4%), 73 (25.3%), and 85 (29.4%) patients, respectively. No differences were found for the GLTEQ scores for all seven functional system groups (P value = 0.168). As for the EDSS disability subgroups, the percentage of active patients (moderately at least) were 60%, 45.8%, 36.5%, and 15.4%, for the very mild, mild, moderate, and severe subgroups, respectively. This study found that participation in leisure-time physical activity is independent from the pyramidal, cerebellar, and sensory functional systems in PwMS.

Cycle ergometer training enhances plasma interleukin-10 in multiple sclerosis

The objective was to determine plasma levels of pro- (IL-12p70/IL-6) and anti-inflammatory (IL-10) cytokines before and after cycle ergometer training in healthy control (HC) and people with multiple sclerosis (pwMS), and to correlate plasma cytokines with physical/mental health. Study participants cycled for 30 min at 65-75% age-predicted maximal heart rate, twice a week for 8 weeks during supervised sessions. We determined that plasma IL-10 expression was lower in pwMS, compared to HCs, and that exercise augmented IL-10 in pwMS to baseline levels in HCs. Furthermore, plasma isolated from pwMS displayed enhanced expression of the pro-inflammatory cytokines IL-12p70/IL-6. Plasma cytokine signatures correlated with physical/mental health. Overall, this study highlights the potential of a short-term exercise programme to regulate circulating cytokine profiles with relevance to pwMS.

Prolonged cortical silent period is related to poor fitness and fatigue, but not tumor necrosis factor, in Multiple Sclerosis

OBJECTIVE

Poor fitness among people with Multiple Sclerosis (MS) aggravates disease symptoms. Whether low fitness levels accompany brain functioning changes is unknown.

METHODS

MS patients (n = 82) completed a graded maximal exercise test, blood was drawn, and transcranial magnetic stimulation determined resting and active motor thresholds, motor evoked potential latency, and cortical silent period (CSP).

RESULTS

Sixty-two percent of participants had fitness levels ranked below 10th percentile. Fitness was not associated with disability measured using the Expanded Disability Status Scale (EDSS). Regression analyses revealed that, cardiorespiratory fitness, when controlling for disease demographics, contributed 23.7% (p < 0.001) to the model explaining variance in CSP. Regression analysis using cardiorespiratory fitness and CSP as predictors showed that CSP alone explained 19.9% of variance in subjective fatigue (p = 0.002). Tumor necrosis factor was not associated with any variable.

CONCLUSION

Low fitness was associated with longer CSP in MS. Longer CSP was, in turn, related to greater MS fatigue.

SIGNIFICANCE

MS patients had extremely low levels of cardiorespiratory fitness. Poor fitness predicted longer CSP, a marker of greater intracortical inhibition, which was linked to MS fatigue. Future research should examine whether aerobic training could shorten CSP and potentially lessen inhibition of cortical networks.

Physical activity in mild multiple sclerosis: contribution of perceived fatigue, energy cost, and speed of walking

Purpose: To clarify the relationship between leisure-time physical activity, perceived fatigue, and energy expenditure while walking in people with multiple sclerosis.Methods: Sixty-six people afflicted with multiple sclerosis (MS) (32 women) with a mild neurological disability, participated in this study. Energy expenditure was separately measured at rest, during comfortable walking and during fast walking via a portable metabolic device using breath-by-breath technology (COSMED K5, COSMED Srl, Rome, Italy). The Godin leisure-time exercise questionnaire assessed leisure-time physical activity. The Modified Fatigue Impact Scale determined the level of perceived fatigue.Results: Seventeen people with MS were classified as physically active; 49 were insufficiently active. Scores recorded on the Godin Leisure-Time Exercise Questionnaire were 47.8 (SD = 18.4), 7.0 (SD = 8.2), respectively. Insufficiently physically active people with MS walked slower at both normal and fast walking conditions. However, no differences between groups were observed in energy expenditure measures in both walking speeds. O₂ cost was 0.20 (SD = 0.13) and 0.21 (SD = 0.06) in the active and insufficiently active group, respectively. The insufficiently active group reported more perceived fatigue compared with the active patients; 33.3 (SD = 18.6) vs. 15.0 (SD = 19.0), p value = 0.002. Perceived fatigue was a significant variable maintaining a 10.4% variance related to leisure-time physical activity.Conclusions: Leisure-time physical activity was inversely associated with perceived fatigue and walking speed in persons with mild MS. Rehabilitation professionals should be aware of these relationships when planning rehabilitation strategies.Implication for rehabilitationThis study found that perceived fatigue is a barrier to physical activity participation even in people with mild multiple sclerosis and minimal disability.Insufficiently active people with multiple sclerosis expend the same amount of energy while walking as active multiple sclerosis individuals, though walking slower.The relationship between perceived fatigue and physical activity participation requires further exploration in the multiple sclerosis population.

Fear of falling, not falls, impacts leisure-time physical activity in people with multiple sclerosis

BACKGROUND

There is a consensus that physical activity is imperative for people with MS (PwMS). However, regardless of the benefits, many PwMS do not participate in any meaningful physical activity.

AIM

To examine the relationship between leisure-time physical activity with clinical characteristics and common symptoms in PwMS.

METHODS

The sample included 190 PwMS (107 women), mean age 40.8 (S.D = 13.1) and mean disease duration of 6.4 (SD = 8.3) years since diagnosis. Outcome measures included the Godin Leisure-Time Exercise Questionnaire (GLTEQ), Four Square Step Test (FSST), 2-Minute Walk test (2 mWT), Timed Up and Go test (TUG), Timed 25-Foot Walk test (T25FW), fall status, Falls Efficacy Scale International (FES-I), Modified Fatigue Impact Scale (MFIS), walking speed and the Multiple Sclerosis Walking Scale self-reported questionnaire (MSWS-12).

RESULTS

Eighty-six PwMS were classified as active (GLTEQ = 31.6 (S.D = 16.7); 104 were insufficiently active (GLTEQ = 3.0 (S.D = 4.3). Insufficiently active PwMS demonstrated a slower walking speed, elevated fatigue, more concerns of falling and additional walking difficulties compared to active PwMS. Non-significant differences between groups were observed in the TUG, 2 mWT, FSST, T25FWT and fall status. According to the linear regression, by utilizing the FES-I we observed a 12.2% variance related to leisure-time physical activity. The independent variables: EDSS, MSWS-12, fatigue and walking speed were non-significant.

SIGNIFICANCE

The present findings highlight the impact of concern of falling on physical activity in PwMS. This knowledge may represent an opportunity to improve care and enhance physical activity in the MS population.

Role of Mast Cells in the Pathogenesis of Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is a neurological autoimmune disorder of the central nervous system (CNS), characterized by recurrent episodes of inflammatory demyelination and consequent axonal deterioration. The hallmark of the disease is the demyelinated plaque, a hypocellular area characterized by formation of astrocytic scars and infiltration of mononuclear cells. Recent studies have revealed that both innate and adaptive immune cells contribute to the pathogenesis of MS and its experimental autoimmune encephalomyelitis (EAE) model. Here, we review the current understanding of the role of mast cells in the pathogenesis of MS and EAE. Mast cells may act at the early stage that promote demyelination through interactions among mast cells, neurons, and other immune cells to mediate neuroinflammation. Studies from EAE model suggest that mast cells regulate adaptive autoimmune responses, present myelin antigens to T cells, disrupt the blood-brain barrier, and permit the entry of inflammatory cells and mediators into the CNS. Depletion or limiting mast cells could be a new promising therapeutic target for MS and EAE.

Toll-Like Receptor 2-Mediated Glial Cell Activation in a Mouse Model of Cuprizone-Induced Demyelination

Multiple sclerosis (MS) is a chronic degenerative disease of the central nervous system that is characterized by myelin abnormalities, oligodendrocyte pathology, and concomitant glia activation. The factors triggering gliosis and demyelination are currently not well characterized. New findings suggest an important role of the innate immune response in the initiation and progression of active demyelinating lesions. Especially during progressive disease, aberrant glia activation rather than the invasion of peripheral immune cells is accountable for progressive neuronal injury. The innate immune response can be induced by pathogen-associated or danger-associated molecular patterns, which are identified by pattern recognition receptors (PRRs), including the Toll-like receptors (TLRs). In this study, we used the cuprizone model in mice to investigate the expression of TLR2 during the course of cuprizone-induced demyelination. In addition, we used TLR2-deficient mice to analyze the functional role of TLR2 activation during cuprizone-induced demyelination and reactive gliosis. We show a significantly increased expression of TLR2 in the corpus callosum and hippocampus of cuprizone-intoxicated mice. The absence of receptor signaling in TLR2-deficient mice resulted in less severe reactive astrogliosis in the corpus callosum and cortex. In addition, microglia activation was ameliorated in the corpus callosum of TLR2-deficient mice, but augmented in the cortex compared to wild-type littermates. Extent of demyelination and loss of mature oligodendrocytes was comparable in both genotypes. These results suggest that the TLR2 orchestrates glia activation during gray and white matter demyelination in the presence of an intact blood-brain barrier. Future studies now have to address the underlying mechanisms of the region-specific TLR2-mediated glia activation.

Impact of short-term cycle ergometer training on quality of life, cognition and depressive symptomatology in multiple sclerosis patients: a pilot study

In this pilot study, we investigate whether a routine cycle ergometry training programme has therapeutic potential in individuals with multiple sclerosis (MS) by improving quality of life (QOL) and depressive symptomatology, while ameliorating cognitive disturbances. Healthy volunteers and MS patients cycled for 30 min at 65-75% age-predicted maximal heart rate on a recumbent ergometer, with this session repeated twice a week for 8 weeks. QOL, depressive symptomatology and cognitive function were assessed pre- and post-exercise using the MS Quality of Life-54 (MSQOL-54) questionnaire, 16-item Quick Inventory of Depressive Symptomatology (QIDS-SR₁₆) questionnaire and the Cambridge Neuropsychological Test Automated Battery (CANTAB), respectively. We determined that QOL was lower in MS patients, compared to healthy subjects, with a reduction in physical and mental health summary scores observed. Exercise improved both physical and mental health scores in MS patients. In support of this, exercise was shown to reduce depressive symptomatology in MS patients. Exercise was also associated with an improvement in visual sustained attention, executive function/cognitive flexibility and hippocampal-dependent visuospatial memory in patients. Overall, this study identifies a short-term exercise programme that improves physical and mental health, while reducing depressive symptomatology and cognitive dysfunction in MS.

Evaluating the Effectiveness of Physical Exercise Interventions in Persons Living With HIV: Overview of Systematic Reviews

Physical exercise (PE) has not been well studied in persons living with HIV (PLHIV). We conducted an overview of systematic reviews to assess the effectiveness of PE and to determine the most appropriate PE regimen for PLHIV. We used the CDC's Prevention Research Synthesis Project's database and manual searches to identify systematic reviews published between 1996 and 2013. We qualitatively synthesized the findings from five reviews to assess the effectiveness of PE and conducted meta-analyses on CD4 counts to identify the best PE regimen. PE is associated with reduced adiposity and depression, but was not associated with a decrease in HIV viral load. CD4 counts were improved by interventions with interval aerobic or 41-50 minutes of exercise three times per week compared with other modes and duration of exercise. PE appears to benefit PLHIV, but more research is needed to help develop appropriate PE strategies specifically for PLHIV.

Formyl Peptide Receptor 1-Mediated Glial Cell Activation in a Mouse Model of Cuprizone-Induced Demyelination

Multiple sclerosis (MS) is a chronic degenerative disease of the central nervous system that is characterized by myelin abnormalities, oligodendrocyte pathology, and concomitant glia activation. Unclear are the factors triggering gliosis and demyelination. New findings suggest an important role of the innate immune response in the initiation and progression of active demyelinating lesions. The innate immune response is induced by pathogen-associated or danger-associated molecular patterns, which are identified by pattern recognition receptors (PRRs), including the G-protein coupled with formyl peptide receptors (FPRs). Glial cells, the immune cells of the central nervous system, also express the PRRs. In this study, we used the cuprizone mice model to investigate the expression of the FPR1 in the course of cuprizone-induced demyelination In addition, we used FPR1-deficient mice to analyze glial cell activation through immunohistochemistry and real-time RT-PCR in cuprizone model. Our results revealed a significantly increased expression of FPR1 in the cortex of cuprizone-treated mice. FPR1-deficient mice showed a slight but significant decrease of demyelination in the corpus callosum compared to the wild-type mice. Furthermore, FPR1 deficiency resulted in reduced glial cell activation and mRNA expression of microglia/macrophages markers, as well as pro- and anti-inflammatory cytokines in the cortex, compared to wild-type mice after cuprizone-induced demyelination. Combined together, these results suggest that the FPR1 is an important part of the innate immune response in the course of cuprizone-induced demyelination.