Tanshinone IIA inhibits ischemia-reperfusion-induced inflammation, ferroptosis and apoptosis through activation of the PI3K/Akt/mTOR pathway

Ischemia-reperfusion (I/R) is a common clinical process, and the lung is one of the most sensitive organs of I/R injury, which often leads to acute lung injury (ALI). Tanshinone IIA (Tan IIA) has anti-inflammatory, antioxidant, and anti-apoptotic activities. However, the effects of Tan IIA on lung I/R injury remain uncertain. Twenty-five C57BL/6 mice were randomly divided into five groups: control (Ctrl), I/R, I/R + Tan IIA, I/R + LY294002 and I/R + Tan IIA + LY294002 group. Tan IIA (30 μg/kg) was injected intraperitoneally 1 h before injury in the I/R + Tan IIA and I/R + Tan IIA + LY294002 groups. These data showed that Tan IIA significantly improved I/R-induced histological changes and scores of lung injury, decreased lung W/D ratio, MPO and MDA contents, reduced infiltration of inflammatory cells, and decreased the expression of IL-1β, IL-6 and TNF-α. Meanwhile, Tan IIA significantly increased the expression of Gpx4 and SLC7A11, and decreased the expression of Ptgs2 and MDA. Moreover, Tan IIA significantly reversed the low expression of Bcl2, and the high expression of Bax, Bim, Bad and cleave-caspase 3. Furthermore, Tan IIA caused a significant increase in the phosphorylation levels of PI3K, Akt and mTOR in the lungs. However, these beneficial effects of Tan IIA on I/R-induced lung inflammation, ferroptosis and apoptosis were offset by LY294002. Our data suggest that Tan IIA significantly ameliorates I/R-induced ALI, which is mediated through activation of PI3K/Akt/mTOR pathway.