However, the cellular mechanism of ATEO against oxidative stress in neuronal cells has not been fully clarified. antioxidant proteins (SODs, GPx, and UCPs). The cytoprotective effect of ATEO was related to upregulation of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1specific knockdown. Using inhibitor of protein kinase A (PKA), we found that cAMP-response element binding protein (CREB) activation was involved in ATEO-induced PGC-1expression. Taken together, we suggest that ATEO effectively prevents H2O2-induced cell injury possibly through the activation of CREB/PGC-1signaling in PC12 cells. The results provide a molecular insight into the effect of ATEO on cytoprotection against oxidative stress. 1. Introduction Oxidative stress is implicated in the pathogenesis of several neurological disorders, including M?89 Alzheimer disease, Parkinson disease, amyotrophic lateral sclerosis, stroke, and depression [1C3]. Excessive reactive oxygen species (ROS) production appears to contribute to cellular damage, impairment of the Rabbit Polyclonal to EHHADH DNA repair system, and mitochondrial dysfunction, all of which are known as key factors M?89 in these neurological disorders [4C6]. The first line of defense against ROS in cells is the detoxifying enzymes that scavenge ROS, including superoxide dismutases (SODs), glutathione peroxidase (GPx), and catalase [7C9]. Another line of defense is the uncoupling proteins (UCPs) that limit mitochondrial ROS overproduction [10]. These proteins have a significant impact on ROS metabolism and the modulation of the antioxidant defense system prevents ROS-mediated damage in neuronal cells. Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1as a master regulatory protein of antioxidant capacity [13, 14]. Studies of neurological disorders reported that the loss of PGC-1expression was closely related to ROS accumulation and neuron loss, while upregulation of PGC-1expression induced the expression of SODs, GPx1, and UCPs and therefore contributed to ROS metabolism. Moreover, the cAMP-response element binding protein (CREB) was shown to function as an upstream activator of PGC-1gene expression to promote neuronal survival [15, 16]. M?89 On the basis of these studies, the activation of CREB/PGC-1signaling suggests a novel and effective neuroprotective target involving oxidative stress. Acori Tatarinowii Rhizoma (ATR, the dried rhizome of Schott) has been one of the most important traditional herbal medicines in China for thousands of years [17, 18]. The application of ATR is used for the treatment of neurological disorders, acting on regaining consciousness, tranquilizing the mind, eliminating dampness, and invigorating the circulation of blood. It is reported that the extracts of ATR enhance neurogenesis and neuroprotection in both animal and M?89 clinical studies [19C21]. According to Chinese Pharmacopoeia, the major active fraction of ATR is the essential oil [22]. Recent studies have reported the application of ATR essential oil (ATEO) in neuroprotection, including the protection against oxidative stress [23, 24]. However, the cellular mechanism of ATEO against oxidative stress in neuronal cells has not been fully elucidated. In this study, the cellular mechanism of ATEO against oxidative stress was investigated. PC12 cells were selected as the cell model due to their phenotypic characteristics of sympathetic neurons [25, 26]. We evaluated whether ATEO had a beneficial effect on H2O2-stressed PC12 cells, including a PGC-1gene expression. Therefore, we investigated whether ATEO-dependent activation of CREB/PGC-1played a crucial role in the protective effect against H2O2-induced injury in PC12 cells. 2. Materials and Methods 2.1. Reagents and Chemicals was performed using a PGC-1specific siRNA (S: 5-CCG AGA AUU CAU GGA GCA ATT-3, AS: M?89 5-UUG CUC CAU GAA UUC UCG GTT-3, Sangon Biotech, Shanghai, China, RS2988). Briefly, PC12 cells were seeded in 6-well plates at a density of 1 1.2??105 cells per well and stayed overnight. The cells were transfected with siRNA (50?nM) using Lipofectamine? RNAiMAX transfection reagent (Thermo Fisher Scientific) according to the manufacturer’s protocol. Cells transfected with NC-siRNA (S: 5-UUC UCC GAA CGU GUC ACG UTT-3, AS: 5-ACG UGA CAC GUU CGG AGA ATT-3, Sangon Biotech, RS2988) were used as controls for direct comparison. 2.6. Cell Viability.