Vagus nerve control of HMGB1 accessibility: a bioelectronic strategy for inflammation and pain

High mobility group box 1 protein (HMGB1) is a central mediator of inflammation and pain, but efforts to neutralize it therapeutically have had limited clinical success. This gap suggests that the essential problem is not simply the abundance of extracellular HMGB1, but its accessibility: its availability to assemble into pathogenic complexes, engage receptors such as the receptor for advanced glycation end products (RAGE), enter cells, and deliver inflammatory cargo to the cytosol. Here, a perspective is advanced that integrates HMGB1 biology with the inflammatory reflex and the cholinergic anti-inflammatory pathway. In this framework, HMGB1 promotes inflammatory entry and amplification, whereas acetylcholine, acting through the vagus nerve and alpha7 nicotinic acetylcholine receptors, limits HMGB1 release and uptake of HMGB1-containing complexes. Vagus nerve stimulation therefore emerges as a bioelectronic strategy to restrict upstream access of danger signals to intracellular inflammatory pathways, in addition to suppressing downstream cytokine signaling. This formulation does not alter the established biology of HMGB1; rather, it places existing observations into a unifying model with direct relevance to inflammation and pain.