Inhibition of acute lung inflammation by a neuroimmune circuit induced by vagal nerve stimulation.
Summary
Selective afferent VNS suppressed TLR7-driven macrophage activation and neutrophil lung recruitment via an adrenal epinephrine–dependent pathway. It engaged nucleus tractus solitarius and rostral ventrolateral medulla; inhibiting these sympathetic control regions abrogated protection. Findings delineate a brain–adrenal–lung anti-inflammatory circuit relevant to sepsis-related lung injury.
Key Findings
- Only selective vagal afferent stimulation inhibited TLR7-driven macrophage activation and neutrophil recruitment to the lung.
- Anti-inflammatory protection required adrenal gland–derived epinephrine; adrenalectomy or epinephrine inhibition abolished VNS benefits.
- Afferent VNS activated the nucleus tractus solitarius and rostral ventrolateral medulla; inhibiting neuronal activity in this region negated VNS efficacy.
Clinical Implications
Supports exploration of afferent-selective VNS as an adjunct to mitigate inflammatory lung injury in sepsis and viral pneumonitis; parameter optimization and patient selection will be key.
Why It Matters
This work uncovers a defined neuroimmune circuit whereby afferent VNS controls lung inflammation through adrenal epinephrine and specific brainstem nuclei, advancing mechanistic understanding and neuromodulation strategies.
Limitations
- Preclinical animal study; clinical translatability and safety of afferent-selective VNS remain to be established
- Incomplete delineation of downstream β-adrenergic receptor subtype involvement
Future Directions
Test afferent-selective VNS in translational models and early-phase trials for sepsis-induced lung injury; map β-adrenergic subtype contributions and optimize stimulation parameters.
Study Information
- Study Type
- Cohort
- Research Domain
- Pathophysiology
- Evidence Level
- V - Preclinical mechanistic animal study elucidating a neuroimmune anti-inflammatory circuit.
- Study Design
- OTHER