Study on the Mechanism of Aspirin Alleviating Kawasaki Disease With Coronary Artery Lesions by Inducing TRAF6 to Regulate STAT3 Ubiquitination and Inhibit Th17 Cell Differentiation.

Among multiple complications of Kawasaki disease (KD), coronary artery lesions (CALs) emerge as the clinically paramount concern. Aspirin therapy can reduce the incidence of KD with CAL, yet its mechanism remains unclear. This study principally investigated the mechanism by which aspirin is effective in treating KD with CAL. Peripheral blood samples from healthy, KD, and KD + CAL children were analyzed using RT-qPCR, western blot, and ELISA to assess the levels of TNF receptor associated factor 6 (TRAF6), signal transducer and activator of transcription 3 (STAT3), and Th17 cells. Spleen CD4+ T cells extracted from mouse were initially activated and subsequently differentiated into Th17 cells for subsequent experiments. After aspirin treatment and the downregulation of TRAF6, IF, ELISA, western blot, and RT-qPCR assessed Th17 differentiation and TRAF6/STAT3 expression. Conversely, the effects of TRAF6 overexpression coupled with MG132 treatment on STAT3 expression were evaluated using RT-qPCR and western blot. Additionally, IP and IF assays were conducted to detect the interaction and ubiquitination modifications between TRAF6 and STAT3. The STRING online tool predicted the interacting proteins of TRAF6, which were then validated through cell experiments. In KD with CAL children, elevated Th17 cell count, reduced TRAF6 expression, and heightened STAT3 expression were observed in the peripheral blood. In cell experiments, aspirin boosted TRAF6 expression, downregulated STAT3, inhibited Th17 differentiation. Dampening TRAF6 expression in cells reversed the impact of aspirin. TRAF6 facilitated the ubiquitination of STAT3, triggering its protein degradation, while UBE2N interacted with TRAF6 to modulate STAT3 expression. This study found that aspirin upregulates TRAF6 to ubiquitinate STAT3, inhibiting Th17 differentiation and improving KD with CAL.