Multiple sclerosis (MS) is a prevalent neurological disorder affecting the central nervous system, with a global incidence exceeding 2.5 million cases. Brain-derived neurotrophic factor-antisense (BDNF-AS), a long non-coding RNA, has been identified as a factor that negatively influences the expression of brain-derived neurotrophic factor, a neurotrophin protein that exhibits heightened expression within actively demyelinating lesions in MS. This study aims to assess the relative expression of BDNF-AS across all MS subtypes, evaluate its diagnostic accuracy, and explore correlations between BDNF-AS expression and disease parameters. Quantitative real-time polymerase chain reaction was employed to quantify the expression levels of BDNF-AS in the serum samples of 54 individuals diagnosed with various types of MS and 20 healthy controls. Statistical analyses were performed to assess the correlation and diagnostic efficacy of BDNF-AS expression levels. The expression of BDNF-AS was markedly reduced in individuals with MS compared to the control group (P < 0.01). Notably, the highest expression levels were observed in patients diagnosed with secondary progressive MS. Using a defined cutoff value of 0.31, and the findings suggest that BDNF-AS expression in serum has notable potential as a specific and sensitive diagnostic marker for MS. In conclusion, this study provides a comprehensive evaluation of BDNF-AS across all MS subtypes, highlighting its diagnostic accuracy and the association between elevated BDNF-AS expression and disease progression in secondary progressive MS. Further research is needed to validate these results.

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