Precision Medicine in Neurodegenerative Diseases: Some Promising Tips Coming from the microRNAs' World

Interferon beta-1a sc at 25 years: a mainstay in the treatment of multiple sclerosis over the period of one generation

INTRODUCTION

Interferon beta (IFN beta) preparations are an established group of drugs used for immunomodulation in patients with multiple sclerosis (MS). Subcutaneously (sc) applied interferon beta-1a (IFN beta-1a sc) has been in continuous clinical use for 25 years as a disease-modifying treatment.

AREAS COVERED

Based on data published since 2018, we discuss recent insights from analyses of the pivotal trial PRISMS and its long-term extension as well as from newer randomized studies with IFN beta-1a sc as the reference treatment, the use of IFN beta-1a sc across the patient life span and as a bridging therapy, recent data regarding the mechanisms of action, and potential benefits of IFN beta-1a sc regarding vaccine responses.

EXPERT OPINION

IFN beta-1a sc paved the way to effective immunomodulatory treatment of MS, enabled meaningful insights into the disease process, and remains a valid therapeutic option in selected vulnerable MS patient groups.

Current Advancement of Immunomodulatory Drugs as Potential Pharmacotherapies for Autoimmunity Based Neurological Diseases

Dramatic advancement has been made in recent decades to understand the basis of autoimmunity-mediated neurological diseases. These diseases create a strong influence on the central nervous system (CNS) and the peripheral nervous system (PNS), leading to various clinical manifestations and numerous symptoms. Multiple sclerosis (MS) is the most prevalent autoimmune neurological disease while NMO spectrum disorder (NMOSD) is less common. Furthermore, evidence supports the presence of autoimmune mechanisms contributing to the pathogenesis of amyotrophic lateral sclerosis (ALS), which is a neurodegenerative disorder characterized by the progressive death of motor neurons. Additionally, autoimmunity is believed to be involved in the basis of Alzheimer’s and Parkinson’s diseases. In recent years, the prevalence of autoimmune-based neurological disorders has been elevated and current findings strongly suggest the role of pharmacotherapies in controlling the progression of autoimmune diseases. Therefore, this review focused on the current advancement of immunomodulatory drugs as novel approaches in the management of autoimmune neurological diseases and their future outlook.

The role of miRNA in retinal ganglion cell health and disease

miRNA are short non-coding RNA responsible for the knockdown of proteins through their targeting and silencing of complimentary mRNA sequences. The miRNA landscape of a cell thus affects the levels of its proteins and has significant consequences to its health. Deviations in this miRNA landscape have been implicated in a variety of neurodegenerative diseases and have also garnered interest as targets for treatment. Retinal ganglion cells are the sole projection neuron of the retina with their axons making up the optic nerve. They are a focus of study not only for their importance in vision and the myriad of blinding diseases characterized by their dysfunction and loss, but also as a model of other central nervous system diseases such as spinal cord injury and traumatic brain injury. This review summarizes current knowledge on the role of miRNA in retinal ganglion cell function, highlighting how perturbations can result in disease, and how modulating their abundance may provide a novel avenue of therapeutic research.

Dysregulation of MicroRNAs and PIWI-Interacting RNAs in a Caenorhabditis elegans Parkinson's Disease Model Overexpressing Human α-Synuclein and Influence of tdp-1

MicroRNAs (miRNAs) and PIWI-interacting RNAs (piRNAs) regulate gene expression and biological processes through specific genetic and epigenetic mechanisms. Recent studies have described a dysregulation of small non-coding RNAs in Parkinson’s disease (PD) tissues but have been limited in scope. Here, we extend these studies by comparing the dysregulation of both miRNAs and piRNAs from transgenic Caenorhabditis elegans (C. elegans) nematodes overexpressing pan-neuronally human α-synuclein wild-type (WT) (HASN^WT OX) or mutant (HASN^A53T OX). We observed 32 miRNAs and 112 piRNAs dysregulated in HASN^A53T OX compared with WT. Genetic crosses of HASN^A53T OX PD animal models with tdp-1 null mutants, the C. elegans ortholog of TDP-43, an RNA-binding protein aggregated in frontal temporal lobar degeneration, improved their behavioral deficits and changed the number of dysregulated miRNAs to 11 and piRNAs to none. Neuronal function-related genes T28F4.5, C34F6.1, C05C10.3, camt-1, and F54D10.3 were predicted to be targeted by cel-miR-1018, cel-miR-355-5p (C34F6.1 and C05C10.3), cel-miR-800-3p, and 21ur-1581 accordingly. This study provides a molecular landscape of small non-coding RNA dysregulation in an animal model that provides insight into the epigenetic changes, molecular processes, and interactions that occur during PD-associated neurodegenerative disorders.

The microRNA let-7b-5p Is Negatively Associated with Inflammation and Disease Severity in Multiple Sclerosis

The identification of microRNAs in biological fluids for diagnosis and prognosis is receiving great attention in the field of multiple sclerosis (MS) research but it is still in its infancy. In the present study, we observed in a large sample of MS patients that let-7b-5p levels in the cerebrospinal fluid (CSF) were highly correlated with a number of microRNAs implicated in MS, as well as with a variety of inflammation-related protein factors, showing specific expression patterns coherent with let-7b-5p-mediated regulation. Additionally, we found that the CSF let-7b-5p levels were significantly reduced in patients with the progressive MS compared to patients with relapsing-remitting MS and were negatively correlated with characteristic hallmark processes of the two phases of the disease. Indeed, in the non-progressive phase, let-7b-5p inversely associated with both central and peripheral inflammation; whereas, in progressive MS, the CSF levels of let-7b-5p negatively correlated with clinical disability at disease onset and after a follow-up period. Overall, our results uncovered, by the means of a multidisciplinary approach and multiple statistical analyses, a new possible pleiotropic action of let-7b-5p in MS, with potential utility as a biomarker of MS course.

Precision and Personalized Medicine: How Genomic Approach Improves the Management of Cardiovascular and Neurodegenerative Disease

Life expectancy has gradually grown over the last century. This has deeply affected healthcare costs, since the growth of an aging population is correlated to the increasing burden of chronic diseases. This represents the interesting challenge of how to manage patients with chronic diseases in order to improve health care budgets. Effective primary prevention could represent a promising route. To this end, precision, together with personalized medicine, are useful instruments in order to investigate pathological processes before the appearance of clinical symptoms and to guide physicians to choose a targeted therapy to manage the patient. Cardiovascular and neurodegenerative diseases represent suitable models for taking full advantage of precision medicine technologies applied to all stages of disease development. The availability of high technology incorporating artificial intelligence and advancement progress made in the field of biomedical research have been substantial to understand how genes, epigenetic modifications, aging, nutrition, drugs, microbiome and other environmental factors can impact health and chronic disorders. The aim of the present review is to address how precision and personalized medicine can bring greater clarity to the clinical and biological complexity of these types of disorders associated with high mortality, involving tremendous health care costs, by describing in detail the methods that can be applied. This might offer precious tools for preventive strategies and possible clues on the evolution of the disease and could help in predicting morbidity, mortality and detecting chronic disease indicators much earlier in the disease course. This, of course, will have a major effect on both improving the quality of care and quality of life of the patients and reducing time efforts and healthcare costs.

Investigation of the miRNA146a and miRNA155 gene expression levels in patients with multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease and the most common neurodegenerative status. MicroRNAs play an important role in macrophage response to inflammatory processes, and alterations in miRNA levels trigger the inactivation of specific T lymphocytes. As a result, these factors can lead to autoimmune diseases such as MS. Therefore, to determine the role of MicroRNA-146a and MicroRNA-155 in MS patients, their expression levels in serum of MS patients were compared with healthy controls. In this study, the expression levels of MicroRNA-146a and MicroRNA-155 in 30 serum samples of MS and healthy patients as a control group. MicroRNA extraction and cDNA synthesis was performed according manufacture protocols. The expression levels of MicroRNAs were evaluated by Real Time-PCR. MicroRNA-146a and MicroRNA-155 levels were increased in patients with MS compared to controls. The results demonstrated that EDSS score are increased with increasing level of MicroRNA-146a and MicroRNA-155. ROC curve analysis showed that the area under curve (AUC) was significant for MicroRNA-146a and MicroRNA-155. Increased expression levels of MicroRNA-146a and MicroRNA-155 may be associated with the pathogenesis of MS disease. If this study is conducted in a larger sample population and the above results can be used to identify patients or control patients who are under medical care.

Assessment of expression profile of microRNAs in multiple sclerosis patients treated with fingolimod

Fingolimod is an immunotherapeutic drug approved in certain countries as first-line therapy for relapsing-remitting multiple sclerosis (RRMS). The drug has been shown to alter the expression of several coding and non-coding genes. In the current study, we assessed the expression of miR-506-3p, miR-217, miR-381-3p, miR-1827, miR-449a and miR-655-3p in peripheral blood of patients with RRMS undergoing treatment with fingolimod compared with healthy controls. We also compared the expression of these miRNAs between fingolimod responders and non-responders to determine their relevance with regard to response to fingolimod. Expression of miR-381-3p was significantly higher in responders than in controls (RE difference = 3.903, P = 0.005), while expression of miR-655-3p was significantly lower in both responders and non-responders compared with controls (RE difference = -1.03, P = 0.014; RE difference = -1.41, P < 0.0001, respectively). No difference was found in the expression of other miRNAs between study subgroups. In addition, there was no significant difference in the expression of any miRNA between responders and non-responders. Although there were significant pairwise correlations between expression levels of all of the assessed miRNAs in controls, MS patients exhibited differences in correlation patterns. Expression of miR-381-3p was correlated with age in responders. However, expression of other miRNAs did not correlate with age in any study subgroup. The current study indicates a possible role for miR-655-3p and miR-381-3p in the pathogenesis of MS or possible effects of fingolimod on the expression of these miRNAs. Future studies are needed to verify these results in larger patient populations.