Serum level of brain-derived neurotrophic factor in patients with relapsing–remitting multiple sclerosis: a potential biomarker for disease activity

Effect of vestibular training on cognitive functions in people with multiple sclerosis: A randomized controlled trial

BACKGROUND

Cognitive dysfunction is prevalent but inadequately treated in people with multiple sclerosis (PwMS). Central vestibular functions are associated with multiple cognitive domains in PwMS, even when controlling for disability status. To our knowledge, the effectiveness of vestibular training on cognition in PwMS has never been explored. The study's purpose was to determine the effect of vestibular training on PwMS's cognitive functions.

METHODS

Forty PwMS with relapsing-remitting MS, primarily fatigued, were randomly divided into two equal groups. The control group (GI) was treated with aerobic endurance exercises using stationary bicycle training. The study group (GII) was treated with aerobic endurance exercises as GI in addition to a designed vestibular training program. Outcome measures of cognition were assessed pre- and post-treatment using the Arabic version of Brief International Cognitive Assessment for MS (BICAMS-A) and serum Brain-derived neurotrophic factor (BDNF).

RESULTS

Post-treatment, there was a significant increase of oral Symbol Digit Modalities Test (SDMT), California Verbal Learning Test II (CVLT-II), revised Brief Visuospatial retention Test (BVRT-R) of BICAMS-A and serum BDNF in both study and control groups. There was a significant increase in CVLT-II, BVRT-R of BICAMS-A and serum BDNF in the study group compared to the control group (P < 0.05).

CONCLUSION

Vestibular training is an effective and innovative approach for improving cognitive functions in PwMS.

TRIAL REGISTRATION

PACTR202311670782148.

The Compelling Role of Brain-Derived Neurotrophic Factor Signaling in Multiple Sclerosis: Role of BDNF Activators

Brain-derived neurotrophic factor (BDNF) is a neurotrophin, acting as a neurotrophic signal and neuromodulator in the central nervous system (CNS). BDNF is synthesized from its precursor proBDNF within the CNS and peripheral tissues. Through activation of NTRK2/TRKB (neurotrophic receptor tyrosine kinase 2), BDNF promotes neuronal survival, synaptic plasticity, and neuronal growth, whereas it inhibits microglial activation and the release of pro-inflammatory cytokines. BDNF is dysregulated in different neurodegenerative diseases and depressions. However, there is a major controversy concerning BDNF levels in the different stages of multiple sclerosis (MS). Therefore, this review discusses the potential role of BDNF signaling in stages of MS, and how BDNF modulators affect the pathogenesis and outcomes of this disease.

The Use of Neurotrophic Factors as a Promising Strategy for the Treatment of Neurodegenerative Diseases (Review)

The review considers the use of exogenous neurotrophic factors in the treatment of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and others. This group of diseases is associated with the death of neurons and dysfunction of the nervous tissue. Currently, there is no effective therapy for neurodegenerative diseases, and their treatment remains a serious problem of modern medicine. A promising strategy is the use of exogenous neurotrophic factors. Targeted delivery of these factors to the nervous tissue can improve survival of neurons during the development of neurodegenerative processes and ensure neuroplasticity. There are methods of direct injection of neurotrophic factors into the nervous tissue, delivery using viral vectors, as well as the use of gene cell products. The effectiveness of these approaches has been studied in numerous experimental works and in a number of clinical trials. Further research in this area could provide the basis for the creation of an alternative treatment for neurodegenerative diseases.

Exploring the mRNA and Plasma Protein Levels of BDNF, NT4, SIRT1, HSP27, and HSP70 in Multiple Sclerosis Patients and Healthy Controls

Multiple sclerosis (MS) is a chronic, autoimmune neurodegenerative disease affecting the central nervous system. It is a major cause of non-traumatic neurological disability among young adults in North America and Europe. This study focuses on neuroprotective genes (BDNF, NT4/5, SIRT1, HSP70, and HSP27). Gene expression and protein levels of these markers were compared between MS patients and healthy controls. Blood samples were collected from 42 patients with multiple sclerosis (MS) and 48 control subjects without MS. Quantitative real-time PCR was performed to measure the expression of specific genes. The samples were analyzed in duplicate, and the abundance of mRNA was quantified using the 2-ΔCt method. ELISA assay was used to measure the concentration of specific proteins in the plasma samples. The results show that a 3.5-fold decrease in the gene expression of BDNF corresponds to a 1.5-fold downregulation in the associated plasma protein concentration (p < 0.001). Similar trends were observed with NT-4 (five-fold decrease, slight elevation in protein), SIRT1 (two-fold decrease, two-fold protein decrease), HSP70 (four-fold increase, nearly two-fold protein increase), and HSP27 (four-fold increase, two-fold protein increase) (p < 0.001). This study reveals strong correlations between gene expression and protein concentration in MS patients, emphasizing the relevance of these neuroprotective markers in the disease.

The Role of BDNF in Multiple Sclerosis Neuroinflammation

Multiple sclerosis (MS) is a chronic, inflammatory, and degenerative disease of the central nervous system (CNS). Inflammation is observed in all stages of MS, both within and around the lesions, and can have beneficial and detrimental effects on MS pathogenesis. A possible mechanism for the neuroprotective effect in MS involves the release of brain-derived neurotrophic factor (BDNF) by immune cells in peripheral blood and inflammatory lesions, as well as by microglia and astrocytes within the CNS. BDNF is a neurotrophic factor that plays a key role in neuroplasticity and neuronal survival. This review aims to analyze the current understanding of the role that inflammation plays in MS, including the factors that contribute to both beneficial and detrimental effects. Additionally, it explores the potential role of BDNF in MS, as it may modulate neuroinflammation and provide neuroprotection. By obtaining a deeper understanding of the intricate relationship between inflammation and BDNF, new therapeutic strategies for MS may be developed.

The Role of Brain-Derived Neurotrophic Factor in Immune-Related Diseases: A Narrative Review

Brain-derived neurotrophic factor (BDNF) is a neurotrophin regulating synaptic plasticity, neuronal excitability, and nociception. It seems to be one of the key molecules in interactions between the central nervous system and immune-related diseases, i.e., diseases with an inflammatory background of unknown etiology, such as inflammatory bowel diseases or rheumatoid arthritis. Studies show that BDNF levels might change in the tissues and serum of patients during the course of these conditions, e.g., affecting cell survival and modulating pain severity and signaling pathways involving different neurotransmitters. Immune-related conditions often feature psychiatric comorbidities, such as sleep disorders (e.g., insomnia) and symptoms of depression/anxiety; BDNF may be related as well to them as it seems to exert an influence on sleep structure; studies also show that patients with psychiatric disorders have decreased BDNF levels, which increase after treatment. BDNF also has a vital role in nociception, particularly in chronic pain, hyperalgesia, and allodynia, participating in the formation of central hypersensitization. In this review, we summarize the current knowledge on BDNF's function in immune-related diseases, sleep, and pain. We also discuss how BDNF is affected by treatment and what consequences these changes might have beyond the nervous system.

Recent Advances on the Role of Brain-Derived Neurotrophic Factor (BDNF) in Neurodegenerative Diseases

Neurotrophins, such as brain-derived neurotrophic factor (BDNF), are essential for neuronal survival and growth. The signaling cascades initiated by BDNF and its receptor are the key regulators of synaptic plasticity, which plays important role in learning and memory formation. Changes in BDNF levels and signaling pathways have been identified in several neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and Huntington's disease, and have been linked with the symptoms and course of these diseases. This review summarizes the current understanding of the role of BDNF in several neurodegenerative diseases, as well as the underlying molecular mechanism. The therapeutic potential of BDNF treatment is also discussed, in the hope of discovering new avenues for the treatment of neurodegenerative diseases.

Blood levels of brain-derived neurotrophic factor (BDNF) in people with multiple sclerosis (MS): A systematic review and meta-analysis

BACKGROUND

Multiple sclerosis is an autoimmune demyelinating disease marked by the involvement of multiple pathophysiological pathways, including BDNF. BDNF (brain-derived neurotrophic factor) is one of the main neurotrophic factors in the adult brain. The amount of BDNF in the blood can be utilized as a surrogate for the central expression of this marker. Given contradicting reports, we set out to answer the question, "How do blood levels of BDNF differ in people with multiple sclerosis (PwMS) compared to controls?"

METHODS

We performed a thorough search in MEDLINE, EMBASE, Web of Science, and the Cochrane Library databases, resulting in 13 eligible investigations. Eleven studies compared BDNF in serum of PwMS versus healthy controls (HC), and two studies provided BDNF levels in the plasma of PwMs. R version 4.0.4 was used for meta-analysis and visualizations. Mean difference (MD) was used for the measurement of effect size.

RESULTS

The final analysis included thirteen studies with 689 patients with MS and 583 controls. The preliminary results indicated that MS patients had statistically significant lower levels of BDNF than controls: SMD -5.1992 (95% CI [-8.4488; -1.9496], p-value < 0.0001. Additionally, subgroup analysis revealed a statistically significant difference in serum and plasma levels (p-value=0.01). Performing univariate meta-regression, disease duration and the proportion of males had, respectively, a significant negative and positive correlation with BDNF levels.

CONCLUSION

Circulating levels of BDNF are decreased in MS. Future studies should investigate the role of BDNF as a biomarker of disease severity and/or progression for a personalized approach to MS.

Melatonin and multiple sclerosis: antioxidant, anti-inflammatory and immunomodulator mechanism of action

BACKGROUND

Melatonin is an indole hormone secreted primarily by the pineal gland that showing anti-oxidant, anti-inflammatory and anti-apoptotic capacity. It can play an important role in the pathophysiological mechanisms of various diseases. In this regard, different studies have shown that there is a relationship between Melatonin and Multiple Sclerosis (MS). MS is a chronic immune-mediated disease of the Central Nervous System.

AIM

The objective of this review was to evaluate the mechanisms of action of melatonin on oxidative stress, inflammation and intestinal dysbiosis caused by MS, as well as its interaction with different hormones and factors that can influence the pathophysiology of the disease.

RESULTS

Melatonin causes a significant increase in the levels of catalase, superoxide dismutase, glutathione peroxidase, glutathione and can counteract and inhibit the effects of the NLRP3 inflammasome, which would also be beneficial during SARS-CoV-2 infection. In addition, melatonin increases antimicrobial peptides, especially Reg3β, which could be useful in controlling the microbiota.

CONCLUSION

Melatonin could exert a beneficial effect in people suffering from MS, running as a promising candidate for the treatment of this disease. However, more research in human is needed to help understand the possible interaction between melatonin and certain sex hormones, such as estrogens, to know the potential therapeutic efficacy in both men and women.

Neuropathic Pain in Multiple Sclerosis and Its Animal Models: Focus on Mechanisms, Knowledge Gaps and Future Directions

Multiple sclerosis (MS) is a multifaceted, complex and chronic neurological disease that leads to motor, sensory and cognitive deficits. MS symptoms are unpredictable and exceedingly variable. Pain is a frequent symptom of MS and manifests as nociceptive or neuropathic pain, even at early disease stages. Neuropathic pain is one of the most debilitating symptoms that reduces quality of life and interferes with daily activities, particularly because conventional pharmacotherapies do not adequately alleviate neuropathic pain. Despite advances, the mechanisms underlying neuropathic pain in MS remain elusive. The majority of the studies investigating the pathophysiology of MS-associated neuropathic pain have been performed in animal models that replicate some of the clinical and neuropathological features of MS. Experimental autoimmune encephalomyelitis (EAE) is one of the best-characterized and most commonly used animal models of MS. As in the case of individuals with MS, rodents affected by EAE manifest increased sensitivity to pain which can be assessed by well-established assays. Investigations on EAE provided valuable insights into the pathophysiology of neuropathic pain. Nevertheless, additional investigations are warranted to better understand the events that lead to the onset and maintenance of neuropathic pain in order to identify targets that can facilitate the development of more effective therapeutic interventions. The goal of the present review is to provide an overview of several mechanisms implicated in neuropathic pain in EAE by summarizing published reports. We discuss current knowledge gaps and future research directions, especially based on information obtained by use of other animal models of neuropathic pain such as nerve injury.