gypenoside-XVII and Brain-Ischemia

To explore the mechanism of gypenoside XVII against cerebral ischemia/reperfusion (I/R) through nuclear factor erythroid 2-related factor 2/antioxidant responsive element (Nrf2/ARE) signaling pathway.. Forty SPF Sprague Dawley (SD) rats were randomly divided into sham operated group, I/R model group, 25, 50 and 100 mg/kg gypenoside XVII groups (n = 8). Gypenoside XVII groups were administered 25, 50 or 100 mg/kg (0.01 mL/g) gypenoside XVII by intragastric administration for 14 days; the other two groups received the same dose of saline. Rat cerebral I/R model was established by modified line bolt method; rats in the sham operated group underwent the same procedure without producing substantial embolization. After 24 hours of reperfusion, the neurological deficit scores of the rats in each group were assessed. Rat abdominal aortic whole blood was collected and the serum reactive oxygen species (ROS), heme oxygenase-1 (HO-1), γ-glutamylcysteine synthase (γ-GCS), superoxide dismutase (SOD), quinone NADH oxidoreductase 1 (NQO1), and malondialdehyde (MDA) were detected. Then whole brain tissue was harvested and penumbra tissue was isolated from cerebral cortex, the general condition of rat brain tissue and the volume of cerebral infarction were evaluated, the histopathological changes in the brain were observed under light microscopy, the mRNA expressions of Nrf2 and Keap1 were measured by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR), the protein expressions of Nrf2 and Keap1 were determined by Western blotting.. Gypenoside XVII (50 mg/kg and 100 mg/kg) may play a role in anti-cerebral I/R injury by regulating NQO1, SOD, HO-1, γ-GCS, ROS and MDA through Nrf2/ARE signaling pathway.

Topics: Actins; Animals; Antioxidants; Brain Ischemia; Kelch-Like ECH-Associated Protein 1; NF-E2-Related Factor 2; Oxidative Stress; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Signal Transduction; Superoxide Dismutase

Mitochondrial autophagy maintains mitochondrial function and cellular homeostasis and plays a critical role in the pathological process of cerebral ischemia/reperfusion injury (CIRI). Whether Gypenoside XVII (GP17) has regulatory effects on mitochondrial autophagy against CIRI remains unclear. The purpose of this study was to investigate the pharmacodynamic effects and mechanisms of GP17 on mitochondrial autophagy after CIRI.. A rat middle cerebral artery occlusion/reperfusion (MCAO/R) model was used to assess the effects of GP17 against CIRI and to explore the underlying mechanisms. An oxygen-glucose deprivation/reoxygenation (OGD/R) cell model was used to verify the ameliorative effects on mitochondrial damage and to probe the autophagy pathways involved in combating neural injuries.. The in vivo results showed that GP17 significantly improved mitochondrial metabolic functions and suppressed cerebral ischemic injury, possibly via the autophagy pathway. Further research revealed that GP17 maintains moderate activation of autophagy under ischemic and OGD conditions, producing neuroprotective effects against CIRI, and that the regulation of mitochondrial autophagy is associated with crosstalk between the SIRT1-FOXO3A and Hif1a-BNIP3 signalling pathway that is partially eliminated by the specific inhibitors AGK-7 and 2-ME.. Overall, this work offers new insights into the mechanisms by which GP17 protects against CIRI and highlights the potential of therapy with Notoginseng leaf triterpene compounds as a novel clinical strategy in humans.

Topics: Animals; Apoptosis; Autophagy; Brain Ischemia; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Infarction, Middle Cerebral Artery; Membrane Proteins; Mitochondria; Proto-Oncogene Proteins; Rats; Reperfusion Injury; Sirtuin 1