title: Sevoflurane Post-conditioning Enhanced Hippocampal Neuron Resistance to Global Cerebral Ischemia Induced by Cardiac Arrest in Rats through PI3K/Akt Survival Pathway.
abstract: The purpose of this current study was to evaluate whether improvement of mitochondrial dysfunction was involved in the therapeutic effect of sevoflurane post-conditioning in global cerebral ischemia after cardiac arrest (CA) via the PI3K/Akt pathway. In the first experiment, animals were randomly divided into three groups: a sham group, a CA group, a CA+sevoflurane post-conditioning group (CA+SE). Sevoflurane post-conditioning was achieved by administration of 2.5% sevoflurane for 30 min after resuscitation. Sevoflurane post-conditioning has a significant neuroprotective effect by increasing survival rates and reducing neuronal apoptosis. Additionally, the gene and protein expression of PGC-1α, NRF-1, and TFAM, the master regulators of mitochondrial biogenesis, were up-regulated in the CA+SE group, when compared to the CA group. Similarly, in contrast to the CA group, mitochondria-specific antioxidant enzymes, including heat-shock protein 60 (HSP60), peroxiredoxin 3 (Prx3), and thioredoxin 2 (Trx2) were also increased in the CA+SE group. Finally, administration of sevoflurane ameliorated mitochondrial reactive oxygen species (ROS) formation and maintained mitochondrial integrity. In the second experiment, we investigated the relationship between the PI3K/Akt pathway and mitochondrial biogenesis and mitochondria-specific antioxidant enzymes in sevoflurane-induced neuroprotection. The selective PI3K inhibitor wortmannin not only eliminated the beneficial biochemical processes of sevoflurane by reducing the level of mitochondrial biogenesis-related proteins and aggravating mitochondrial integrity, but also reversed the elevation of mitochondria-specific antioxidant enzymes induced by sevoflurane. Therefore, our data suggested that sevoflurane post-conditioning provides neuroprotection via improving mitochondrial biogenesis and integrity, as well as increasing mitochondria-specific antioxidant enzymes by a mechanism involving the PI3K/Akt pathway.
authors.affiliation: Department of Anesthesiology, Affiliated Xiangya Hospital of Central South UniversityChangsha, China; Department of Anesthesiology, Hainan General HospitalHaikou, China.
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Anesthesiology, Affiliated Xiangya Hospital of Central South University Changsha, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Ye
authors.affiliation: Emergency Department, Affiliated Xiangya Hospital of Central South University Changsha, China.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Huang
authors.affiliation: Department of Anesthesiology, Affiliated Xiangya Hospital of Central South University Changsha, China.
authors.forename: Na
authors.initials: N
authors.lastname: Wang
authors.affiliation: Department of Anesthesiology, Affiliated Xiangya Hospital of Central South University Changsha, China.
authors.forename: E
authors.initials: E
authors.lastname: Wang
authors.affiliation: Department of Anesthesiology, Affiliated Xiangya Hospital of Central South University Changsha, China.
authors.forename: Qulian
authors.initials: Q
authors.lastname: Guo
keywords: PI3K/Akt; global cerebral ischemic injury; mitochondrial biogenesis; post-conditioning; sevoflurane