Dexmedetomidine Protects Against Oxygen–Glucose Deprivation-Induced Injury Through Inducing Astrocytes Autophagy via TSC2/mTOR Pathway

Although there is an increment in stroke burden in the world, stroke therapeutic strategies are still extremely limited to a minority of patients. We previously demonstrated that dexmedetomidine (DEX) protects against focal cerebral ischemia via inhibiting neurons autophagy. Nevertheless, the role of DEX in regulating astrocytes autophagic status in oxygen–glucose deprivation, a condition that mimics cerebral ischemia, is still unknown. In this study, we have shown that DEX and DEX + RAPA (autophagy inducer) increased viability and reduced apoptosis of primary astrocytes in oxygen–glucose deprivation (OGD) model compared with DEX + 3-methyladenine (3-MA) (autophagy inhibitor). DEX induced the expression of microtubule-associated protein 1 light chain 3 (LC3) and Beclin 1, while reduced the expression of p62 in primary cultured astrocytes through induction of autophagy. In addition, DEX enhanced the expression of tuberous sclerosis complex 2 (TSC2) in primary cultured astrocytes, while reduced the expression of mammalian target of rapamycin (mTOR). In conclusion, our study suggests that DEX exerts a neuroprotection against OGD-induced astrocytes injury via activation of astrocytes autophagy by regulating the TSC2/mTOR signaling pathway, which provides a new insight into the mechanisms of DEX treatment for acute ischemic injury.