Study of Correlation Between Serum BDNF Levels and Pfirmann Grading and IL- 1β

Brain-derived neurotrophic factor (BDNF) is a protein belonging to the neurotrophin family, known to be involved in neuronal survival, growth, and synaptic plasticity. Recent studies suggest that the role of BDNF may extend beyond the central nervous system to include inflammatory responses and degenerative changes in peripheral tissues. In particular, BDNF expression has been confirmed within intervertebral disc tissue, with degenerated discs showing increased BDNF expression compared to normal discs, and this expression has been reported to increase further with the severity of degeneration Intervertebral disc degeneration is closely associated with intradiscal nerve ingrowth (neoinnervation) and the resulting generation of pain, and BDNF has been reported as a factor mediating this nerve ingrowth and pain sensitization (central/peripheral sensitization) within the disc. Interleukin-1 beta (IL-1β), a representative inflammatory cytokine of disc degeneration, is known as a key mediator that promotes extracellular matrix degradation within disc tissue and induces neoinnervation and sensitization. Because BDNF secretion from neurons and immune cells has also been reported to increase in inflammatory environments, a potential interaction between IL-1β and BDNF has been proposed Accordingly, this study aims to measure serum BDNF concentrations in patients presenting with low back and leg pain due to disc degeneration or spinal stenosis, and to analyze whether these levels show a consistent correlation with Pfirrmann grading on MRI and serum IL-1β concentration.