Inhibition of PTEN protects PC12 cells against oxygen-glucose deprivation induced cell death through mitoprotection.

Mitochondria involve in the determination of ischemic neuronal cell fate through regulation of apoptotic and necrotic cell death. Phosphatase and tensin homolog (PTEN) protein negatively regulates Akt/PKB signaling which is the major cell survival pathway. The current study aimed to examine the impact of SF1670, a potent PTEN inhibitor, on mitochondria-mediated cell survival pathways in an in vitro stroke-like model. PC12 cells were exposed to one hour oxygen and glucose deprivation (OGD) followed by different time points of reperfusion (0, 30, 60, 120 and 180 min) and SF1670 treatments. Our findings showed that OGD/R exposure increased reactive oxygen species (ROS) levels, reduced phosphorylated Akt (p-Akt), ratios of Bcl-2/BAX, intracellular ATP, mitochondrial vital activity and mitochondrial membrane potential (Δψm). OGD/R exposure also increased cleaved caspase 3/pro-caspase 3 and cleaved caspase 9/pro-caspase 9 ratios associated with low cell viability, high lactate dehydrogenase (LDH) release, and greater apoptotic cell death in the TUNEL assay. Conversely, inhibition of PTEN by SF1670 were associated with increased expression of p-Akt and anti-apoptotic proteins (Bcl-2), attenuated pro-apoptotic proteins (BAX) and oxidative stress index (ROS), improved mitochondrial function (restored MMP and ATP), and decreased apoptotic cell death. These results strongly suggest that neuroprotective effect of SF1670 against OGD/R-induced cell death at least is partially mediated through mitoprotective properties of SF1670.