Oxidative stress induced by combined glyphosate and TBBPA exposure promotes gill autophagy and inflammation via the PI3K/AKT/mTOR pathway

Abstract

Glyphosate and tetrabromobisphenol A (TBBPA) are pollutants that pose a serious threat to the ecological safety of aquatic environments. However, there has been no report on the effects of combined exposure on the toxicity of carp fish gills in water. Therefore, we constructed a model of carp gill tissue and the carp epithelioma cells (EPC) cells exposed to glyphosate and/or TBBPA in vitro and in vivo, established a control group, a glyphosate group, a TBBPA group, and a glyphosate + TBBPA group, and added PI3K/AKT pathway activator musk ketone in vitro to verify the relationship between toxins and pathways. qRT-PCR and western blotting methods were used to detect the expression of oxidative stress-related indicators (CAT, GSH-Px, T-AOC, H₂O₂) and related genes. In vitro and in vivo results showed that glyphosate and/or TBBPA exposure resulted in overproduction of ROS, decreased activity of CAT, GSH-Px, T-AOC, and increased H₂O₂ content. Glyphosate and/or TBBPA exposure inhibited the PI3K/AKT/mTOR signaling pathway, further resulting in increased autophagy related genes LC3, ATG-5, Beclin-1, and decreased p62 expression. Inflammation related genes TNF-α, IL-1β, IL-6, IL-18 increased. And it was more significant when exposed in combination than when exposed alone. The addition of PI3K/AKT signaling pathway activator musk ketone in vitro can significantly alleviate the changes of autophagy and inflammation-related indicators. In summary, glyphosate and/or TBBPA induce oxidative stress by promoting gill autophagy and inflammation via the PI3K/AKT/mTOR pathway.