The significance of reticulon4A as a potential indicator of neurodegeneration

Abstract Background Neurodegeneration characterizes by dysfunction, progressive atrophy and loss of neurons, which is presented in both neurodegenerative as well as demyelinating disorders. Both groups of diseases share common pathological hallmarks: neuroinflammation and gradual loss of neurons and axons, which lead to the central nervous system (CNS) damage and the development of these disorders. Mounting evidence has supported the reticulon4A (RTN4A) role in the pathogenesis of some neurodegenerative and demyelinating disorders, including MS. RTN4A also known as Nogo‐A protein, contributes to neuroinflammation and demyelination. Moreover, this protein acts as a relevant inhibitor of neurite outgrowth and axonal regeneration. Therefore, the objectives of the present study were evaluation of Nogo‐A and Tau levels in the cerebrospinal fluid (CSF) of MS patients and subjects from the control group, as well as the assessment of a relationships between concentrations of immunoglobulins, albumin, immunoglobulins and albumin quotients, as well as oligoclonal bands. Method The concentrations of Nogo‐A and Tau proteins were measured in the CSF of 15 MS patients and 16 subjects from control group by means of quantitative technique ELISA. CSF and serum concentrations of albumin and immunoglobulins were measured by using nephelometer. To evaluate the integrity of the blood‐CSF barrier and intrathecal immunoglobulins production, albumin and immunoglobulins quotients were calculated. Furthermore, the oligioclonal bands were assessed by using isoelectofocusing method. Result The CSF concentrations of Nogo‐A was significantly higher in MS group in comparison with controls. The increased CSF level of the protein was observed significantly correlate with the concentration of Tau protein in MS patients. Furthermore, we revealed associations between Nogo‐A protein and CSF levels of albumin, Tau and QIgG in the whole study group. Conclusion Our preliminary results indicate a potential role of Nogo‐A protein in the neurodegenerative pathology of MS. Moreover, it seems that reticuon4A is a promising candidate biomarker for demyelinating disorders, including MS, but these investigations need to be further clarified using a larger study group. The study was conducted with the use of equipment purchased by Medical University of Białystok as part of the RPOWP 2007‐2013 funding, Priority I, Axis 1.1, contract No. UDA‐RPPD.01.01.00‐20‐001/15‐00 dated 26.06.2015.