Carvacryl acetate, a semisynthetic monoterpenic ester obtained from essential oils, provides neuroprotection against cerebral ischemia reperfusion-induced oxidative stress injury via the Nrf2 signalling pathway

Abstract

Carvacryl acetate (CA) is a semisynthetic monoterpenic ester obtained from essential oils, and it exerts an antioxidation effect. The purpose of our study was to investigate whether CA could provide neuroprotection against oxidative stress caused by cerebral ischemia–reperfusion injury (CIRI) and elucidate the underlying mechanism. Middle cerebral artery occlusion (MCAO)-induced damage was established in Sprague Dawley (SD) rats and PC12 cells were exposed to hydrogen peroxide (H₂O₂) to imitate oxidative stress damage. TTC, HE and Nissl staining were used to observe the pathological morphology of lesions. The contents of ROS and MDA, and the activity of SOD were measured to reflect the level of oxidative stress. In addition, the TUNEL method was used to assess injuries in vitro, and the expression of Nrf2 was determined by immunohistochemical staining and western blot analysis. Importantly, we constructed and validated Nrf2 knockdown PC12 cells to confirm the key role of Nrf2 in the neuroprotective effect of CA against oxidative stress injuries. CA alleviated CIRI in rats with MCAO, as shown by brain tissue pathophysiology. The contents of ROS and MDA were reduced, and the SOD activity was augmented by the simultaneous promotion of Nrf2 expression. In addition, the H₂O₂-induced injury in Nrf2-knockdown PC12 cells was more serious than it was in control cells, and CA-mediated neuroprotection was exclusively inhibited by the knock down of Nrf2 in PC12 cells. In conclusion, it is shown here that CA has the effect of relieving cerebral ischemia reperfusion-induced oxidative stress injury via the Nrf2 signalling pathway.