title: The effect of concentration and duration of normobaric oxygen in reducing caspase-3 and -9 expression in a rat-model of focal cerebral ischaemia.
abstract: The aim of this study was to determine the effect of different concentrations of normobaric oxygen (NBO) on neurological function and the expression of caspase-3 and -9 in a rat model of acute cerebral ischaemia. Sprague-Dawley rats (n=120) were randomly divided into four groups (n=30 per group), including 3 groups given NBO at concentrations of 33%, 45% or 61% and one control group given air (21% oxygen). After 2h of ischaemic occlusion, each group was further subdivided into six subgroups (n=5) during reperfusion according to the duration (3, 6, 12, 24, 48 or 72h) and concentration of NBO (33%, 45% or 61%) or air treatment. The Fluorescence Quantitative polymerase chain reaction (PCR) and immunohistochemistry were used to detect caspase-3 and -9 mRNA and protein relative expression respectively. The Neurologic Impairment Score (NIS) was significantly lower in rats given 61% NBO ≥3h after reperfusion when compared to the control group (P<0.05, Mann-Whitney U). NBO significantly reduced caspase-3 and -9 mRNA and protein expression when compared to the control group at all NBO concentrations and time points (P<0.05, ANOVA). The expression of caspase-3 and -9 was lower in the group given 61% NBO compared any other group, and this difference was statistically significant when compared to the group given 33% NBO for ≥48h and the control group (both P<0.05, ANOVA). These findings indicate that NBO may inhibit the apoptotic pathway by reducing caspase-3 and -9 expression, thereby promoting neurological functional recovery after stroke.
authors.affiliation: Department of Medical Nursing, School of nursing, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Suyan
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Medical Nursing, School of nursing, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Huizhen
authors.initials: H
authors.lastname: Peng
authors.affiliation: School of Nursing, Midwifery & Social Care, Edinburgh Napier University, Edinburgh, Scotland.
authors.forename: Anne
authors.initials: A
authors.lastname: Rowat
authors.affiliation: Department of Neuroimmunology, Henan academy of Medical and Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
authors.affiliation: Department of Medical Nursing, School of nursing, Zhengzhou University, Zhengzhou, Henan, China. Electronic address: zhangzx6666@126.com.
authors.forename: Zhenxiang
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Medical Nursing, School of nursing, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Medical Nursing, School of nursing, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Weihong
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Pathology, The second affiliated hospital, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Xianyuan
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Medical Nursing, School of nursing, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Lixia
authors.initials: L
authors.lastname: Qu
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000628:therapy*; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism*; D053453:Caspase 9 / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects*; D008297:Male; D009460:Neurologic Examination; D010100:Oxygen / Q000008:administration & dosage*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D018709:Statistics, Nonparametric
chemical_list: D012333:RNA, Messenger; D053148:Caspase 3; D053453:Caspase 9; D010100:Oxygen
keywords: Apoptosis; Cerebral ischaemic–reperfusion; Ischaemic rat model; Normobaric oxygen