Evaluating the effect of ginsenoside Rg1 on CPF‐induced brain injury in mice via PI3k/AKT pathway

Abstract Organophosphorus pesticides (OPs) have long been used extensively on agricultural land and can lead to significant improvements in crop yields. Due to occupational exposure, humans are exposed to pesticides through dermal contact, inhalation, and ingestion. The effects of OPs on the organism are currently studied for their effects on livers, kidneys, hearts, blood indicators, neurotoxicity, and teratogenic, carcinogenic, and mutagenic effects, while studies in the direction of brain tissue damage have not been reported in detail. Previous reports have confirmed that ginsenoside Rg1 is a prominent and representative tetracyclic triterpenoid derivative rich in ginseng and has good neuroprotective activity. Considering that, the aim of this study was to establish a mouse model of brain tissue injury by using the OP‐type pesticide chlorpyrifos (CPF) and to explore the therapeutic effects and possible molecular mechanisms of Rg1. Mice in the experimental group were pre‐protected with Rg1 by gavage for 1 week, and brain tissue damage was induced using CPF (5 mg/kg for 1 week) to assess the effect of Rg1 (80 and 160 mg/kg for 3 weeks) in alleviating brain damage. Morris water maze and histopathological analysis were performed to assess cognitive function and pathological changes in the mouse brain, respectively. Protein expression levels of Bax, Bcl‐2, Caspase‐3, Cl‐Cas‐3, Caspase‐9, Cl‐Cas‐9, phosphoinositide 3‐kinase (PI3K), phosphorylated‐PI3K, protein kinase B (AKT), and phosphorylated‐AKT were quantified by protein blotting analysis. Rg1 obviously restored CPF‐induced oxidative stress damage in mouse brain tissue, increased the levels of antioxidant parameters (total superoxide dismutase, total antioxidative capacity, and glutathione) in the brain, and significantly reduced the overexpression of apoptosis‐related proteins induced by CPF. At the same time, Rg1 also markedly attenuated the histopathological changes in the brain induced by CPF exposure. Mechanistically, Rg1 could effectively activate the phosphorylation of PI3K/AKT. Furthermore, molecular docking studies revealed a stronger binding capacity between Rg1 and PI3K. Rg1 attenuated neurobehavioural alterations and reduced lipid peroxidation in the mouse brain to a great extent. Apart from that, Rg1 administration improved brain histopathology in CPF‐induced rats. All results suggest that ginsenoside Rg1 has potential antioxidant effects on CPF‐induced oxidative brain injury, and it is evident that Rg1 could be used as a promising therapeutic strategy for the study of brain injury from OP poisoning.