Quercetin attenuates DEHP-induced pyroptosis and programmed necrosis in chicken duodenum through regulation of the TLR4/MyD88/NF-κB pathway

Di(2-ethylhexyl) phthalate (DEHP) is not only popularly used as a plasticizer, but also ubiquitous in environment, causes an important risk to the lives and well-being of poultry. Quercetin (QUE) is a natural flavonoid with antioxidant, anti-inflammatory, anticancer and immunoregulation. Nevertheless, it's still unclear possibly DEHP causes duodenal pyroptosis and programmed necrosis in broiler chickens or perhaps QUE has a mitigating impact in this mechanism. Therefore, the present investigation was conducted to establish a model of tissue and duodenal progenitor cells models based on DEHP and QUE exposure, and in vitro experiments were added the nuclear factor-kappa-B activator1 (NF-κB Act1) and reactive oxygen species activator (Sanguinarine). The mechanism of duodenal injury was explored by immunofluorescence, Western blot and qRT-PCR. It was shown that exposure to DEHP resulted in decreased depth of the duodenal crypt, shortened cilia length, upregulation of oxidative stress markers, downregulation of antioxidant markers, and a significant increase in the promotion of ROS expression in chicken duodenum. DEHP also promoted the expression of the TLR4/MyD88/NF-κB pathway, as well as the expression of genes associated with pyroptosis and programmed necrosis. While in the DEHP + QUE co-treatment group, QUE regulated the antioxidant capacity of the duodenum and inhibited the TLR4/MyD88/NF-κB pathway, which reduced DEHP-induced pyroptosis and programmed necrosis to some extent. In in vitro experiments where NF-κB Act1 and Sanguinarin were added to the co-treated treatment group, NF-κB signalling was activated and re-up-regulated the levels of genes related to cellular pyroptosis and programmed necrosis alleviated by QUE, which further demonstrated that this pathway could regulate chicken duodenal pyroptosis and programmed necrosis. Thus, quercetin alleviated DEHP-induced chicken duodenal pyroptosis and programmed necrosis via the regulation of the TLR4/MyD88/NF-κB. This investigation supplies a theoretical footing for the hazard valuation of the plasticizer DEHP for poultry.