Efficacy of atopic dermatitis alleviation through transcutaneous auricular vagus nerve stimulation in 2,4-dinitrochlorobenzene (DNCB)-induced mouse model

BACKGROUND: Atopic dermatitis (AD) commonly begins in early childhood, and non-pharmacological treatment options remain limited. Vagal cholinergic signaling can modulate immune responses, suggesting a potential role for neuromodulation in inflammatory skin disease. This study investigated whether transcutaneous auricular vagus nerve stimulation (taVNS) alleviates AD-like skin inflammation and whether acetylcholine receptor signaling contributes to its effects. METHODS: AD-like dermatitis was induced in BALB/c mice using 2,4-dinitrochlorobenzene (DNCB). taVNS (0.2 mA, 15 Hz for 5 min) was applied every 2-3 days for 1 or 2 weeks. Histopathology changes and inflammatory marker expression were assessed in lesional skin. To explore the underlying mechanism, acetylcholine receptor antagonism was used. RESULTS: taVNS improved histological features and reduced inflammatory markers compared with DNCB alone. These effects were partially attenuated by acetylcholine receptor antagonism, suggesting involvement of cholinergic signaling, including α7 nicotinic acetylcholine receptors. CONCLUSION: taVNS may be a promising non-invasive adjunctive approach for AD. Its anti-inflammatory effects appear to be associated, at least in part, with cholinergic signaling pathways, warranting further mechanistic and translational studies.