“…This theory is independent of the coenzyme functions of vitamin B 12 described above, and is instead based on the role of B 12 in the regulation of cytokines and growth factors. The theory is largely the work of Scalabrino and colleagues, who have developed a subacute combined degeneration model in the totally gastrectomized rat [50]. Using this model, they have demonstrated that B 12 deficiency leads to increased spinal cord synthesis and increased CSF levels of two myelinotoxic cytokines, tumor necrosis factor (TNF)-α and soluble (s) CD40:sCD40 ligand dyad, and a myelinotoxic growth factor, nerve growth factor (NGF).…”