Thermoregulatory dysfunction in multiple sclerosis

Neurological patients confronting climate change: A potential role for the glymphatic system and sleep

Interest in the health consequences of climate change (global warming, heatwaves) has increased in the neurological community. This review addresses the impact of elevated ambient temperatures and heatwaves on patients with neurological and mental health disorders, including multiple sclerosis, synucleinopathies, dementia, epilepsies, mental health, and stroke. Patients with such conditions are highly vulnerable during heatwaves because of functional disorders affecting sleep, thermoregulation, autonomic system reactivity, mood, and cognitive ability. Several medications may also increase the risk of heatstroke. Special attention is devoted to the involvement of common underlying mechanisms, such as sleep and the glymphatic system. Disease prevention and patient care during heatwaves are major issues for caregivers. Beyond the usual recommendations for individuals, we favor artificially induced acclimation to heat, which provides preventive benefits with proven efficacy for healthy adults.

Establishing vitreous glucose and beta-hydroxybutyrate thresholds to assist in the diagnosis of hypothermia

The post-mortem diagnosis of hypothermia is challenging to establish due to the lack of pathognomonic findings and the confounding problem that any comorbidity may account for death. A 4-year retrospective case-control study was performed to compare the vitreous glucose and beta-hydroxybutyrate (BHB) concentrations between hypothermia deaths and controls. Over the study period 34 cases of hypothermia and 39 controls were analyzed. Hypothermia deaths versus controls had higher mean vitreous glucose (2.93 mmol/L vs. 1.14 mmol/L; p < 0.0001), BHB (1.89 mmol/L vs. 1.35 mmol/L; p = 0.01), and combined glucose+BHB (4.83 mmol/L vs. 2.46 mmol/L; p < 0.0001). Receiver operating characteristic (ROC) curves showed that the best model for predicting hypothermia in all cases was a combined vitreous glucose+BHB threshold of 2.03 mmol/L (sensitivity 88.2 %; specificity 56.4 %). A sub-group analysis broken down by detectable levels of blood ethanol showed that cases of hypothermia with and without ethanol maintained higher median vitreous glucose relative to the controls (2.05 vs. 0.35 mmol/L and 2.70 vs. 0.65 mmol/L; p = 0.02), however median BHB was only significantly elevated when ethanol was absent (1.88 vs. 1.42 mmol/L; p < 0.0001). Subsequent ROC curve analysis demonstrated that a better model for predicting hypothermia was in cases when blood ethanol was absent. In those deaths vitreous BHB alone had the best area under the curve, with an optimum threshold of 1.83 mmol/L (sensitivity 83.3 %; specificity 96.3 %). This study shows that post-mortem vitreous glucose and BHB are useful ancillary studies to assist in the diagnosis of hypothermia. Ethanol however is a confounder and can alter the utility of vitreous BHB when diagnosing hypothermia in those who have consumed alcohol prior to death.

Human temperature regulation under heat stress in health, disease, and injury

The human body constantly exchanges heat with the environment. Temperature regulation is a homeostatic feedback control system that ensures deep body temperature is maintained within narrow limits despite wide variations in environmental conditions and activity-related elevations in metabolic heat production. Extensive research has been performed to study the physiological regulation of deep body temperature. This review focuses on healthy and disordered human temperature regulation during heat stress. Central to this discussion is the notion that various morphological features, intrinsic factors, diseases, and injuries independently and interactively influence deep body temperature during exercise and/or exposure to hot ambient temperatures. The first sections review fundamental aspects of the human heat stress response, including the biophysical principles governing heat balance and the autonomic control of heat loss thermoeffectors. Next, we discuss the effects of different intrinsic factors (morphology, heat adaptation, biological sex, and age), diseases (neurological, cardiovascular, metabolic, and genetic), and injuries (spinal cord injury, deep burns, and heat stroke), with emphasis on the mechanisms by which these factors enhance or disturb the regulation of deep body temperature during heat stress. We conclude with key unanswered questions in this field of research.

Effects of EMG-Controlled Video Games on the Upper Limb Functionality in Patients with Multiple Sclerosis: A Feasibility Study and Development Description

Multiple sclerosis (MS) is the most common inflammatory neurological disease in young adults, with a high prevalence worldwide (2.8 million people). To aid in the MS treatment, using VR tools in cognitive and motor rehabilitation of such disease has been growing progressively in the last years. However, the role of VR as a rehabilitative tool in MS treatment is still under debate. This paper explores the effects of VR training using EMG activation in upper limb functionality. An experimental training protocol using video games controlled using an MYO armband sensor was conducted in a sample of patients with MS. Results support the use of EMG-commanded video games as a rehabilitative tool in patients with MS, obtaining favorable outcomes related to upper limb functionality and satisfaction.

Thermal dysregulation in patients with multiple sclerosis during SARS-CoV-2 infection. The potential therapeutic role of exercise

Thermoregulation is a homeostatic mechanism that is disrupted in some neurological diseases. Patients with multiple sclerosis (MS) are susceptible to increases in body temperature, especially with more severe neurological signs. This condition can become intolerable when these patients suffer febrile infections such as coronavirus disease-2019 (COVID-19). We review the mechanisms of hyperthermia in patients with MS, and they may encounter when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Finally, the thermoregulatory role and relevant adaptation to regular physical exercise are summarized.

Vitamin D status, proinflammatory cytokines and bone mineral density in Mexican people with multiple sclerosis

BACKGROUND

Vitamin D (VD) has been classically associated with calcium homeostasis and bone mineral density since it has a key role on mineralization and resorption. Immunomodulatory effects have been attributable to VD; low concentrations of VD have been associated with elevation of inflammatory markers. Inflammatory autoimmune diseases, such as multiple sclerosis (MS), a chronic neurodegenerative suffering, whose etiology is still unknown, is directly related to an increase in pro-inflammatory cytokines such as interleukin 17 and interleukin 1β who play an important role in this physiopathology. Nowadays, even though additional studies have linked MS's clinical signs with low VD concentration, there is scarce information of this association in people from regions with sufficient sun exposure. The aim of this study was to evaluate serum VD and cytokine concentrations, and bone density, in Mexican people with MS.

METHODS

Vitamin D (25OHD), interleukin 1β, interleukin 6 and interleukin 17 concentrations of twenty-five volunteers with MS were determined by enzyme-linked immunosorbent assay. Bone mineral density and body composition assessment was performed by dual energy X-Ray absorptiometry.

RESULTS

A mean concentration of 17.3 ± 4.6 ng/ml of 25OHD was obtained, in a range of 5.15 to 25.71 ng/ml; when international advisory bodies thresholds were applied 76% of the participants exhibited some degree of VD inadequacy. Pro-inflammatory markers were detectable among the participants: interleukin 1β in 100%, interleukin 6 in 64%, whereas interleukin 17 was found in 24% of the volunteers. Bone mineral density below the expected for the age was found in 8% of the participants, with lumbar spine as the most affected anatomic region. Non-significant correlations were found between VD and bone mineral density (Z-score) or pro-inflammatory markers.

CONCLUSION

Although non-significant correlations were found between VD and bone mineral density or cytokines, it is important to highlight that an important percentage of our participants exhibited some degree of VD inadequacy, an unknown fact for them, since these are not included in routine clinical evaluations. The low concentrations of VD among this sample regardless of annual UVB sun exposure may suggest the involvement of endogenous and not environmental factors. Further works are needed in order to deepen the physiological causes and effects of VD deficiency in people with MS.

Exercise and Sports Science Australia (ESSA) position statement on exercise for people with mild to moderate multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS), the most common chronic and progressive neurological condition of the central nervous system, affects 26,000 Australian adults. Exercise training has beneficial effects on MS-related impairments including reduced muscular strength, poor aerobic capacity and impaired mobility, and in consequence can improve quality of life. This Position Statement provides evidence-based recommendations for exercise prescription and delivery of exercise training for people with MS with mild to moderate disability.

DESIGN AND METHODS

Synthesis of published works within the field of exercise training in MS.

RESULTS

Exercise provides many benefits to people with MS. There is strong evidence that resistance and aerobic training, performed 2 to 3 times per week at a moderate intensity, are safe and can improve muscle strength, cardiorespiratory fitness, balance, fatigue, functional capacity, mobility and quality of life in people with MS with mild to moderate disability (Expanded Disease Severity Scale (EDSS) ≤ 6.5). However, the evidence for those with severe disability (EDSS >6.5) is less clear. The effects of exercise on MS pathogenesis, central nervous structures and other outcomes such as depression and cognitive impairment, have not been adequately investigated. Effective exercise interventions to improve balance, joint contractures and reduce falls in people with MS are also urgently needed as well as investigations of long-term (≥1 year) effects of exercise training.

CONCLUSIONS

Resistance and aerobic training exercises are effective to alleviate some characteristic signs and symptoms in MS and should be supplemented by balance exercise to prevent falls. Exercise training programs should be prescribed and delivered by qualified exercise professionals. It is important to recognise and accommodate exercise-associated complications such as fatigue and heat sensitivity.

The "Treatise on the spleen and stomach" (Pí Wèi Lùn) as the first record of multiple sclerosis in the medical literature - A hypothesis based on the analysis of clinical presentation and herbal medicine

Background

The “Treatise on the spleen and stomach” (Pí Wèi Lùn) is the work of the scholar and physician Li Gao (Jin-Yuan dynasties, 1115–1368 C.E., China). Li Gao described a clinical presentation that today would fall under the diagnosis of Multiple Sclerosis (MS) and proposed the treatment with herbal medicine and nutritional guidelines. The PWL is well known for its application in the treatment of MS and autoimmune conditions. However, this theoretical “MS” has not yet been analyzed through a scientific investigation, and research on its herbal formulations for MS is scant.

Methods

We analyzed the PWL “MS” clinical presentation considering biomedical diagnostic criteria and neurological correlates. To support our review, we searched Pubmed for studies on the PWL main herbal formulas and their herbs/isolates used for the believed “MS” which treated experimental autoimmune encephalomyelitis (EAE)/MS.

Results

We found a very close correlation between the PWL “MS” and the current MS diagnosis. Twenty four studies on the herbs-isolates showed significant amelioration of EAE, neuronal damage, and demyelination.

Discussion

Collectively, Astragali radix, Ginseng radix, Glycyrrhizae radix, and berberine containing Phellodendri cortex reduced the severity of EAE through different signaling pathways and mechanisms of action. These herbs provided a wide range of properties such as anti-inflammatory, anti-oxidant, anti-microglial activation, anti-infiltration of leukocytes, apoptotic/anti-apoptotic balance, and neuronal protection.

Conclusion

Our review proposes that the PWL is the first record of MS in the medical literature. Its formulas and herbs-isolates offer a fertile area for MS research and an invaluable potential for its treatment.

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We propose that the Pí Wèi Lùn is the first record of MS in the medical literature.

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All twenty four studies on the PWL’s selected herbs/isolates showed improvement of EAE.

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Different signaling pathways/mechanisms of action provided synergistic properties.

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In the PWL, the gastrointestinal system is key for MS and science supports it.

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The PWL offers a fertile area of research and enormous potential for MS treatment.

Comfortable walking speed and energy cost of locomotion in patients with multiple sclerosis

Comfortable walking speed and energy cost of walking are physiological markers of metabolic activity during gait. People with multiple sclerosis are characterized by altered gait biomechanics and energetics, related to the degree of disability and spasticity, which lead to an increased energy cost of walking. Several studies concerning the energy cost of walking in multiple sclerosis have been published. Nevertheless, differences in protocols and characteristics of the sample have led to different outcomes. The aim of the present meta-analysis is to summarize results from studies with specific inclusion characteristics, and to present data about the comfortable walking speed and the energy cost of walking at that speed. Moreover, a detailed discussion of the potential mechanisms involved in the altered metabolic activity during exercise was included. A total of 19 studies were considered, 12 of which were also part of the quantitative analysis. Despite the strict selection process, high between-group heterogeneity was found for both outcomes. Nevertheless, the overall results suggest a pooled mean comfortable walking speed of 1.12 m/s (95% CI 1.05-1.18) and energy cost of 0.19 mLO₂/kg/m (95% CI 0.17-0.21). These findings support the results of previous studies suggesting that energy cost of walking may be increased by 2-3 times compared to healthy controls (HC), and encourage the use of this marker in association with other parameters of the disease.

Flammer syndrome in multiple sclerosis: diagnostics, prediction, and personalization of treatments

Background

Flammer syndrome (FS) occurs from well-described signs and symptoms. The syndrome itself is not a disease, but it may be a directive marker for advancing therapeutic approaches by predictive and preventive measures as well as for personalization of treatments. The syndrome is related to many diseases, but FS has been rarely studied in multiple sclerosis (MS). The study aimed to determine whether FS signs and symptoms occur more often in people with MS than in healthy controls, and in order to personalize the treatment, we investigated the possible effect of current therapies on FS signs and symptoms.

Methods

Two hundred twenty-two MS patients and 203 healthy controls answered the questionnaire consisting of 15 signs and symptoms of FS.

Results

MS patients had significantly more complaints in 9 items of FS signs and symptoms (cold hands or/and feet, the reduced feeling of thirst, dizziness, drug side effects, other headaches (tension-type, medication overuse), weight loss, feeling cold, long sleep-onset time, and skin blotches) compared to healthy controls. Six items (low blood pressure, tinnitus, increased odor sensitivity, low pain threshold, and perfectionism) were similar between the two groups. The treatment agents currently used did not have any effect on the signs and symptoms of FS.

Conclusion

This study showed that FS might be associated with MS. Injectable or oral agents are not related to the signs and symptoms of FS. Further studies are needed to validate this association.

Relevance of the article for predictive preventive and personalized medicine

FS is common among MS patients. Being aware of this incidence that might impair the life quality of MS patients is useful to predict the comorbidity and develop preventive strategies and applying personalized treatment options and procedures.