The Effect of IFN-β Treatment on Plasma Levels of BDNF and IL-6 in Relapsing-Remitting Multiple Sclerosis Patients

The Role of Selected Interleukins in the Development and Progression of Multiple Sclerosis-A Systematic Review

Multiple sclerosis is a disabling inflammatory disorder of the central nervous system characterized by demyelination and neurodegeneration. Given that multiple sclerosis remains an incurable disease, the management of MS predominantly focuses on reducing relapses and decelerating the progression of both physical and cognitive decline. The continuous autoimmune process modulated by cytokines seems to be a vital contributing factor to the development and relapse of multiple sclerosis. This review sought to summarize the role of selected interleukins in the pathogenesis and advancement of MS. Patients with MS in the active disease phase seem to exhibit an increased serum level of IL-2, IL-4, IL-6, IL-13, IL-17, IL-21, IL-22 and IL-33 compared to healthy controls and patients in remission, while IL-10 appears to have a beneficial impact in preventing the progression of the disease. Despite being usually associated with proinflammatory activity, several studies have additionally recognized a neuroprotective role of IL-13, IL-22 and IL-33. Moreover, selected gene polymorphisms of IL-2R, IL-4, IL-6, IL-13 and IL-22 were identified as a possible risk factor related to MS development. Treatment strategies of multiple sclerosis that either target or utilize these cytokines seem rather promising, but more comprehensive research is necessary to gain a clearer understanding of how these cytokines precisely affect MS development and progression.

Chelation Therapy Associated with Antioxidant Supplementation Can Decrease Oxidative Stress and Inflammation in Multiple Sclerosis: Preliminary Results

An imbalance of oxy-inflammation status has been involved in axonal damage and demyelination in multiple sclerosis (MS). The aim of this study was to investigate the efficacy of an antioxidant treatment (calcium disodium ethylenediaminetetracetic acid-EDTA) chelation therapy associated with a micronutrient complex in MS patients. A total of 20 MS patients and 20 healthy subjects, enrolled as a control group (CTR), were recruited. We measured the plasma ROS production and total antioxidant capacity (TAC) by a direct assessment using Electron Paramagnetic Resonance; activities of the antioxidant system (thiols' redox status and enzymes); and the urinary presence of biomarkers of oxidative stress by immunoenzymatic assays. We also evaluated the levels of inflammation by plasmatic cytokines (TNFα, IL-1β, and IL-6) and assessed the sICAM levels, as well as the nitric oxide (NO) catabolism and transthyretin (TTR) concentration. Comparing CTR and MS, in the latter ROS production, oxidative damage, inflammatory biomarkers, and NO metabolite concentrations results were significantly higher, while TAC was significantly lower. Treatment in MS induced significant (p < 0.05) down-regulating of pro-inflammatory sICAM1, TNF-α, IL6, as well as biomarkers of lipid peroxidation and DNA damage production. The protective effect exhibited may occur by decreasing ROS production and increasing antioxidant capacity, turning into a more reduced thiols' status.

In Vitro Evaluation of Apoptosis, Inflammation, Angiogenesis, and Neuroprotection Gene Expression in Retinal Pigmented Epithelial Cell Treated with Interferon α-2b

Angiogenesis, retinal neuropathy, and inflammation are the main molecular features of diabetic retinopathy (DR) and should be taken into consideration for potential treatment approaches. Retinal pigmented epithelial (RPE) cells play a major role in DR progression. This study evaluated the in vitro effect of interferon (IFN) α-2b on the expression of genes involved in apoptosis, inflammation, neuroprotection, and angiogenesis in RPE cells. RPE cells were cocultured with IFN α-2b at 2 doses (500 and 1,000 IU) and treatment periods (24 and 48 h). The quantitative relative expression of genes (BCL-2, BAX, BDNF, VEGF, and IL-1b) was evaluated in the treated versus control cells through real-time polymerase chain reaction (PCR). The result of this study demonstrated that IFN treatment at 1,000 IU (48 h) led to significant upregulation of BCL-2, BAX, BDNF, and IL-1b; however, the BCL-2/BAX ratio was not statistically altered from 1:1, in any of the treatment patterns. We also showed that VEGF expression was downregulated in RPE cells treated with 500 IU for 24 h. It can be concluded that IFN α-2b was safe (BCL-2/BAX ∼1:1) and enhanced neuroprotection at 1,000 IU (48 h); however-at the same time-IFN α-2b induced inflammation in RPE cells. Moreover, the antiangiogenic effect of IFN α-2b was solely observed in RPE cells treated with 500 IU (24 h). It seems that IFN α-2b in lower doses and short duration exerts antiangiogenic effects and in higher doses and longer duration has neuroprotective and inflammatory effects. Hence, appropriate concentration and duration of treatment, according to the type and stage of the disease, should be considered to achieve success in IFN therapy.

Interleukin-6, undercarboxylated osteocalcin, and brain-derived neurotrophic factor responses to single and repeated sessions of high-intensity interval exercise

OBJECTIVES

The purpose of this study was to compare the effects of a single session of high-intensity interval exercise (HIIE) with 2 consecutive HIIEs, separated by 3 h of recovery, on plasma interleukin-6 (IL-6), undercarboxylated osteocalcin (ucOC), and brain-derived neurotrophic factor (BDNF) responses.

METHODS

Twenty male recreational endurance athletes completed two HIIE trials in a randomized crossover design: a single session of HIIE on the single exercise day (HIIE-S) and two sessions of HIIE 3 h apart on the double exercise day (HIIE-D). The HIIE protocol consisted of 10 × 1 min cycling at 100 % of peak oxygen uptake, with 75 s of low-intensity cycling at 60 W. Blood samples were collected to analyze IL-6, ucOC, and BDNF levels before and immediately after HIIE on the HIIE-S and before and immediately after the second HIIE on the HIIE-D.

RESULTS

Both HIIE interventions significantly increased (p &lt; 0.001) plasma IL-6 (HIIE-S 33.90 % vs HIIE-D 31.04 %; p = 0.64), ucOC (HIIE-S 37.18 % vs HIIE-D 39.54 %; p = 0.85), and BDNF levels (HIIE-S 236.01 % vs HIIE-D 216.68 %; p = 0.69), with no group effect.

CONCLUSIONS

Our results demonstrate that performing two consecutive HIIEs on the same day with a 3-h rest results in similar changes in plasma levels of IL-6, BDNF, and ucOC compared with a single session of HIIE.

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.

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.