Hydrogen Gas Inhalation Treatment for Coronary Artery Lesions in a Kawasaki Disease Mouse Model

Background: Kawasaki disease (KD) is a syndrome primarily affecting young children, typically under the age of five, and is characterized by the development of acute vasculitis. Through extensive research conducted on both murine and human subjects, it has been demonstrated that heightened levels of reactive oxygen species (ROS) play a pivotal role in the development of KD, especial coronary artery lesions (CALs). Hydrogen gas exhibits potent antioxidant properties that effectively regulate ROS production and the inflammatory response. Methods: We used Lactobacillus casei cell wall extract (LCWE)-induced vasculitis in mice as an animal model of KD and treated the mice with hydrogen gas inhalation. Results: We observed significant dilatation and higher Z scores in the left coronary artery (LCA) in D21 and D28 in mice after LCWE treatment compared to the control group (p < 0.001) and a significant resolution of LCA diameters (p < 0.01) and Z scores (p < 0.01) after treatment with inhaled hydrogen gas. We further demonstrated that serum IL-6 expression was higher in mice after LCWE treatment (p < 0.01) and IL-6 significantly decreased after inhaled hydrogen gas therapy (p < 0.001). Conclusion: According to our literature review, this is the first report where hydrogen gas inhalation has been demonstrated to be effective for the treatment of coronary artery dilatation in a KD murine model.