Multiple Sclerosis: Basic and Clinical

TNF-alfa Gene Polymorphism Associations with Multiple Sclerosis

Background:TNF-α has a dual role in multiple sclerosis (MS), contributing to both protective and harmful effects. It activates immune cells, promotes the formation of inflammatory lesions in the central nervous system, and stimulates the production of other pro-inflammatory cytokines and chemokines, leading to myelin destruction and neuronal damage. Our research focused on investigating the relationship between TNF-alpha (rs1800630, rs1800629, and rs361525) gene polymorphisms and MS. Methods: 250 healthy controls and 250 multiple sclerosis (MS) patients were included in the study. DNA was extracted from leucocytes from peripheral venous blood by salt precipitation. Single nucleotide polymorphisms (SNPs) were tested using RT-PCR. Statistical analysis of the data was performed using IBM SPSS Statistics 29.0 data analysis software. Results: The analysis revealed that the rs361525 AG genotype was significantly less frequent in the MS group compared to the control group (4.0% vs. 7.2%, p = 0.042). Sex-specific analysis showed a significant difference in genotype distribution (GG, AG, AA) among males between the MS group and the control group (97.7%, 0%, 2.3% vs. 90.6%, 9.4%, 0%, p = 0.005). For the rs1800629 polymorphism, significant results were also found. In subjects younger than 39 years, the A allele was significantly less frequent in the MS group than in the control group (8.6% vs. 15.0%, p = 0.030). The most robust model indicated that the AA genotype reduced the odds of MS by approximately 2 fold compared to the AG + GG genotype (p = 0.044), and each A allele reduced the odds of MS by approximately 2 fold (p = 0.028). The rs1800630 A allele was significantly more common in males in the MS group than in the control group (21.0% vs. 12.9%, p = 0.046). Conclusions: In conclusion, our study identifies significant associations between TNF-alpha gene variants and MS. Specifically, the rs631525 AG genotype was less common in the MS group, with notable sex-specific differences observed. The rs1800629 A allele was statistically significantly less frequent in the MS group than in the control group, and the AA genotype reduced the odds of MS occurrence by ~2 fold compared with the AG + GG genotypes. Additionally, each A allele of rs1800629 was linked to a 2-fold decreased odds of MS occurrence. In males, the rs1800630 A allele was more frequent in the MS group. These findings highlight the relevance of TNF-alpha genetic variations in MS susceptibility, suggesting potential avenues for further research and therapeutic exploration.

Investigating the Potential Influence of TAS2R16 Genetic Variants and Protein Levels on Multiple Sclerosis Development

The study aimed to investigate the association between the TAS2R16 gene (rs860170, rs978739, rs1357949), TAS2R16 serum levels, and multiple sclerosis (MS). A total of 265 healthy control subjects and 218 MS patients were included in the study. Single nucleotide polymorphisms (SNPs) were tested by real-time polymerase chain reaction (RT-PCR). The serum concentration of TAS2R16 was measured using the ELISA method. Analyses revealed that the TAS2R16 rs860170 TT genotype was statistically significantly less frequent in the MS group than in the control group (p = 0.041), and the CC genotype was statistically significantly more frequent in the MS group than in the control group (p < 0.001). In the most robust (codominant) model, the CC genotype was found to increase the odds of MS by ~27-fold (p = 0.002), and each C allele increased the odds of MS by 1.8-fold (p < 0.001). Haplotype analysis of the rs860170, rs978739, and rs1357949 polymorphisms showed that the C-C-A haplotype was associated with a ~12-fold increased odds of MS occurrence (p = 0.02). Serum TAS2R16 levels were elevated in the MS group compared to control subjects (p = 0.014). Conclusions: The rs860170, rs978739, and rs1357949 polymorphisms demonstrated that the C-C-A haplotype and elevated TAS2R16 serum levels can promote the development of MS. These preliminary findings underscore the importance of specific genetic variants, such as rs860170, rs978739, and rs1357949, in MS risk. Additionally, elevated TAS2R16 serum levels in MS patients suggest a potential role in MS pathogenesis. These findings provide insights into the genetic and molecular mechanisms underlying MS and pave the way for personalized diagnostic and therapeutic strategies. Integrating genetic and serum biomarker data in MS research offers promising avenues for improving clinical outcomes and advancing precision medicine approaches in the future.

Ocrevus reduces TH40 cells, a biomarker of systemic inflammation, in relapsing multiple sclerosis (RMS) and in progressive multiple sclerosis (PMS)

Treating MS has been difficult. One successful drug is Ocrelizumab (anti-CD20), used for the chronic relapsing MS (RMS) and the progressive MS (PMS) forms. TH40 cells are pathogenic effector T cells that increase in percentage and numbers during chronic inflammation. Here we show that in the earliest MS course, clinically isolated syndrome (CIS), TH40 cells expand in number. In PMS TH40 cell numbers remain expanded demonstrating sustained chronic inflammation. In RMS TH40 cells were found in CSF and express CD20. Ocrelizumab reduced TH40 cells to healthy control levels in patients. During treatment inflammatory cytokine producing TH40 cells were decreased.

Validity of an inertial sensor-based system for the assessment of spatio-temporal parameters in people with multiple sclerosis

Background

Gait variability in people with multiple sclerosis (PwMS) reflects disease progression or may be used to evaluate treatment response. To date, marker-based camera systems are considered as gold standard to analyze gait impairment in PwMS. These systems might provide reliable data but are limited to a restricted laboratory setting and require knowledge, time, and cost to correctly interpret gait parameters. Inertial mobile sensors might be a user-friendly, environment- and examiner-independent alternative. The purpose of this study was to evaluate the validity of an inertial sensor-based gait analysis system in PwMS compared to a marker-based camera system.

Methods

A sample N = 39 PwMS and N = 19 healthy participants were requested to repeatedly walk a defined distance at three different self-selected walking speeds (normal, fast, slow). To measure spatio-temporal gait parameters (i.e., walking speed, stride time, stride length, the duration of the stance and swing phase as well as max toe clearance), an inertial sensor system as well as a marker-based camera system were used simultaneously.

Results

All gait parameters highly correlated between both systems (r > 0.84) with low errors. No bias was detected for stride time. Stance time was marginally overestimated (bias = -0.02 ± 0.03 s) and gait speed (bias = 0.03 ± 0.05 m/s), swing time (bias = 0.02 ± 0.02 s), stride length (0.04 ± 0.06 m), and max toe clearance (bias = 1.88 ± 2.35 cm) were slightly underestimated by the inertial sensors.

Discussion

The inertial sensor-based system captured appropriately all examined gait parameters in comparison to a gold standard marker-based camera system. Stride time presented an excellent agreement. Furthermore, stride length and velocity presented also low errors. Whereas for stance and swing time, marginally worse results were observed.

Generation of functional human oligodendrocytes from dermal fibroblasts by direct lineage conversion

Oligodendrocytes, the myelinating cells of the central nervous system, possess great potential for disease modeling and cell transplantation-based therapies for leukodystrophies. However, caveats to oligodendrocyte differentiation protocols ( Ehrlich et al., 2017; Wang et al., 2013; Douvaras and Fossati, 2015) from human embryonic stem and induced pluripotent stem cells (iPSCs), which include slow and inefficient differentiation, and tumorigenic potential of contaminating undifferentiated pluripotent cells, are major bottlenecks towards their translational utility. Here, we report the rapid generation of human oligodendrocytes by direct lineage conversion of human dermal fibroblasts (HDFs). We show that the combination of the four transcription factors OLIG2, SOX10, ASCL1 and NKX2.2 is sufficient to convert HDFs to induced oligodendrocyte precursor cells (iOPCs). iOPCs resemble human primary and iPSC-derived OPCs based on morphology and transcriptomic analysis. Importantly, iOPCs can differentiate into mature myelinating oligodendrocytes in vitro and in vivo. Finally, iOPCs derived from patients with Pelizaeus Merzbacher disease, a hypomyelinating leukodystrophy caused by mutations in the proteolipid protein 1 (PLP1) gene, showed increased cell death compared with iOPCs from healthy donors. Thus, human iOPCs generated by direct lineage conversion represent an attractive new source for human cell-based disease models and potentially myelinating cell grafts.

Multiple Sclerosis and related disorders

Multiple Sclerosis (MS) is a common neuroinflammatory disorder which is associated with disabling clinical consequences. The MS disease process may involve neural centers implicated in the control of breathing, leading to ventilatory disturbances during both wakefulness and sleep. In this chapter, a brief overview of MS disease mechanisms and clinical sequelae including sleep disorders is provided. The chapter then focuses on obstructive sleep apnea-hypopnea (OSAH) which is the most prevalent respiratory control abnormality encountered in ambulatory MS patients. The diagnosis, prevalence, and clinical consequences as well as data on effects of OSAH treatment in MS patients are discussed, including the impact on the disabling symptom of fatigue and other clinical sequelae. We also review pathophysiologic mechanisms contributing to OSAH in MS, and in turn mechanisms by which OSAH may impact on the MS disease process, resulting in a bidirectional relationship between these two conditions. We then discuss central sleep apnea, other respiratory control disturbances, and the pathogenesis and management of respiratory muscle weakness and chronic hypoventilation in MS. We also provide a brief overview of Neuromyelitis Optica Spectrum Disorders and review current data on respiratory control disturbances and sleep-disordered breathing in that condition.

Magnetic Resonance Imaging and Clinical Features of the Demyelinating Degeneration of White Matter in Young Patients

Objective

Magnetic resonance imaging (MRI) of brain white matter demyelination often focuses on demyelinating disease, cerebral small vascular disease diagnosis, and follow-up of cognitive dysfunction for observation. This study explored MRI findings and clinical manifestations of demyelinating degeneration of white matter in young patients.

Methods

A total of ninety-four patients with white matter degeneration diagnosed with MRI were enrolled in this study from January 2014 to July 2018. These patients were divided into two groups: the demyelinating disease group (n = 43) and the non-demyelinating disease group (n = 51). The imaging findings and clinical manifestations of the two groups were analyzed.

Results

Compared with the non-demyelinating group, there were more female than male patients in the demyelinating group (P < 0.05). In addition, of the 45 patients with an imaging result of “demyelinating degeneration of white matter and multiple sclerosis,” 39 patients met the diagnosis of multiple sclerosis (86.7%). In comparison, of the 49 patients with an imaging result of “demyelinating degeneration of white matter,” only four patients met the diagnosis for demyelinating disease (8.2%).

Conclusion

In patients complaining of headaches, dizziness, vertigo, and other symptoms and in the case of an imaging result showing the demyelinating degeneration of white matter alone, the possibility of a clinical diagnosis of a demyelinating disease is minimal.

Oligodendrocyte dysfunction and regeneration failure: A novel hypothesis of delayed encephalopathy after carbon monoxide poisoning

Carbon monoxide (CO) poisoning usually causes brain lesions and delayed encephalopathy, also known as delayed neurological sequelae (DNS). Demyelination of white matter (WM) is one of the most common sites of abnormalities in patients with DNS, but its mechanisms remain unclear. Oligodendrocytes (OLs) are myelinated cells that ensure the rapid conduction of neuronal axon signals and provide the nutritional factors necessary for maintaining nerve integrity in the central nervous system (CNS). OLs readily regenerate and replace damaged myelin membranes around axons in the adult mammalian CNS following demyelination. The ability to regenerate OLs depends on the availability of precursor cells (OPCs) in the CNS of adults. Multiple injury-related signals can induce OPC expansion followed by OL differentiation, axonal contact and myelin regeneration (remyelination). Therefore, OL dysfunction and regeneration failure in the deep WM of the brain are the key pathophysiological mechanisms leading to delayed brain injury after CO poisoning. CO-induced toxicity may interfere with OL function and render OPCs unable to regenerate OLs through some unclear mechanisms, leading to progressive demyelinating damage and resulting in DNS. In the future, combination therapies to reduce OL damage and promote OPC differentiation and remyelination may be important for the prevention and treatmentof DNS after CO poisoning.