ビタミンDの神経因性疼痛における役割：生物学的メカニズムと臨床的関連性

Neuropathic pain remains a major clinical challenge due to its complex pathophysiology and limited treatment efficacy. Recent evidence suggests that vitamin D, beyond its classical role in bone and mineral metabolism, exerts neuroprotective and immunomodulatory effects that may influence pain perception. This review synthesizes current findings on the relationship between vitamin D status and neuropathic pain, highlighting potential mechanisms such as modulation of neuroinflammation, regulation of neuronal excitability, and influence on neurotransmitter pathways. Observational studies frequently report an association between vitamin D deficiency and increased pain severity, while interventional trials indicate that supplementation may alleviate neuropathic symptoms in specific populations. However, results remain heterogeneous, and mechanistic studies are still emerging. Understanding the interplay between vitamin D and neuropathic pain could open new avenues for adjunctive therapeutic strategies and personalized medicine approaches. Further high-quality clinical trials and mechanistic research are warranted to clarify causality and optimize clinical applications.