Elucidating the protective role of quercetin against lipopolysaccharide-induced necroptosis in broiler thymus: insights from Nrf2/PERK signaling based on network pharmacology and experimental validation

OBJECTIVES: Quercetin (QUE) possesses antioxidant, anti-inflammatory, and immunomodulatory functions. Nuclear factor erythroid 2-related factor 2 (Nrf2) can initiate protein kinase RNA-like ER kinase (PERK), leading to immune dysfunction and necroptosis. Our findings elucidate the therapeutic potential of QUE in attenuating LPS-induced injury in immune tissues. METHODS: Broilers and MSB-1 cells were treated with LPS or/and QUE. We also treated MSB-1 cells with an Nrf2 inhibitor (ML385), a PERK activator (MK-28), and a necroptosis inhibitor (NSA) to further explore the detailed mechanism. In addition, we further conducted network pharmacology and bioinformatics to analyze the regulatory relationship between QUE and genes. RESULTS: Combined analysis of network pharmacology and bioinformatics uncovered QUE regulates Nrf2 activation and its crosstalk with PERK signaling, influencing calcium homeostasis, necroptosis, and inflammation. Based on experimental validation, our findings demonstrated QUE treatment reduced LPS-induced imbalance in redox homeostasis through Nrf2 signaling pathway. QUE treatment downregulated the expression of cytokines linked to ERS, necroptosis, and inflammation. In addition, QUE treatment protected against LPS-induced immune function disorders. CONCLUSION: QUE treatment efficiently attenuated thymus immune disorders and necroptosis in broilers through Nrf2/PERK signaling. This investigation enriches biological function of QUE, providing a solid foundation for developing its potential application.