Syringaldehyde Exhibits Antibacterial and Antioxidant Activities against Infection.

Tuberculosis (TB) is caused by infection with (), which has a unique resistance to many antimicrobial agents. TB has emerged as a significant worldwide health issue because of the rise of multidrug-resistant strains causing drug-resistant TB (DR-TB). As a result, the development of new drugs or effective strategies is crucial for patients with TB. () and are both species of mycobacteria. In zebrafish, proliferates and forms chronic granulomatous infections, which are similar to infections in lung tissue. Syringaldehyde (SA) is a member of the phenolic aldehyde family found in various plants. Here, we investigated its antioxidative and antibacterial properties in -infected cells and zebrafish. Our results demonstrated that SA inhibits -infected pulmonary epithelial cells and inhibits the proliferation of in -infected zebrafish, suggesting that SA provides an antibacterial effect during infection. Further study demonstrated that supplementation with SA inhibits the production of malondialdehyde (MDA) and reactive oxygen species (ROS) and increases the levels of reduced glutathione (GSH) in -infection-induced macrophages. SA inhibits the levels of MDA in -infected zebrafish, suggesting that SA exerts antioxidative effects in vivo. Additionally, we found that SA promotes the expression of NRF2/HO-1/NQO-1 and the activation of the AMPK-α1/AKT/GSK-3β signaling pathway. In summary, our data demonstrated that SA exerts antioxidative and antibacterial effects during infection both in vivo and in vitro and that the antioxidative effects of SA may be due to the regulation of NRF2/HO-1/NQO-1 and the AMPK-α1/AKT/GSK-3β signaling pathway.