Cadmium (Cd) and excessive molybdenum (Mo) have adverse impacts on animals. However, the hepatotoxicity co-induced by Cd and Mo in ducks has not been fully elucidated. In order to explore the impacts of Cd and Mo co-exposure on pyroptosis and apoptosis by the PTEN/PI3K/AKT pathway in the livers of ducks, 40 healthy 7-day-old Shaoxing ducks (Anas platyrhynchos) were randomly assigned into 4 groups, and Cd or/and Mo were added to the basic diet per kilogram (kg): control group (0 mg Mo and 0 mg Cd), Mo group (100 mg Mo), Cd group (4 mg Cd), and Mo + Cd group (100 mg Mo and 4 mg Cd), with 16 weeks feed management. Results signified that Cd or/and Mo caused trace element imbalance, liver function and histomorphological abnormalities in the duck liver, and activated the PTEN/PI3K/AKT pathway through increasing PTEN mRNA and protein levels, reducing PI3K, AKT mRNA and p-AKT/AKT protein levels, which triggered pyroptosis and apoptosis via increasing Caspase-1, NLRP3, NEK7, ASC, GSDME, GSDMA, IL-1β and IL-18 mRNA levels, Caspase-1 p20, NLRP3, ASC and GSDMD protein levels, and IL-1β and IL-18 contents, and increasing Bak-1, Bax, Cyt C and Caspase-3 mRNA levels and cleaved Caspase-3/Caspase-3 protein level, and downregulating Bcl-2 mRNA level and the ratio of Bcl-2 to Bax, respectively. Overall, the results illustrate that pyroptosis and apoptosis induced by Cd or/and Mo may be associated with activating the PTEN/PI3K/AKT pathway in the livers of ducks. There may be a synergy between these two elements.

Oxidative stress can adversely affect the health status of the body, more specifically by causing intestinal damage by disrupting the permeability of the intestinal barrier. This is closely related to intestinal epithelial cell apoptosis caused by the mass production of reactive oxygen species (ROS). Baicalin (Bai) is a major active ingredient in Chinese traditional herbal medicine that has antioxidant, anti-inflammatory, and anti-cancer properties. The purpose of this study was to explore the underlying mechanisms by which Bai protects against hydrogen peroxide (H₂O₂)-induced intestinal injury in vitro. Our results indicated that H₂O₂ treatment caused injury to IPEC-J2 cells, resulting in their apoptosis. However, Bai treatment attenuated H₂O₂-induced IPEC-J2 cell damage by up-regulating the mRNA and protein expression of ZO-1, Occludin, and Claudin1. Besides, Bai treatment prevented H₂O₂-induced ROS and MDA production and increased the activities of antioxidant enzymes (SOD, CAT, and GSH-PX). Moreover, Bai treatment also attenuated H₂O₂-induced apoptosis in IPEC-J2 cells by down-regulating the mRNA expression of Caspase-3 and Caspase-9 and up-regulating the mRNA expression of FAS and Bax, which are involved in the inhibition of mitochondrial pathways. The expression of Nrf2 increased after treatment with H₂O₂, and Bai can alleviate this phenomenon. Meanwhile, Bai down-regulated the ratio of phosphorylated AMPK to unphosphorylated AMPK, which is indicative of the mRNA abundance of antioxidant-related genes. In addition, knockdown of AMPK by short-hairpin RNA (shRNA) significantly reduced the protein levels of AMPK and Nrf2, increased the percentage of apoptotic cells, and abrogated Bai-mediated protection against oxidative stress. Collectively, our results indicated that Bai attenuated H₂O₂-induced cell injury and apoptosis in IPEC-J2 cells through improving the antioxidant capacity through the inhibition of the oxidative stress-mediated AMPK/Nrf2 signaling pathway.