The effect of concentration and duration of normobaric oxygen in reducing caspase-3 and -9 expression in a rat-model of focal cerebral ischaemia

Chen, Suyan; Peng, Huizhen; Rowat, Anne; Gao, Feng; Zhang, Zhenxiang; Wang, Peng; Zhang, Weihong; Wang, Xianyuan; Qu, Lixia

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 2 h 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 72 h) 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 ≥3 h 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 ≥48 h 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.

Citation

Chen, S., Peng, H., Rowat, A., Gao, F., Zhang, Z., Wang, P., Zhang, W., Wang, X., & Qu, L. (2015). The effect of concentration and duration of normobaric oxygen in reducing caspase-3 and -9 expression in a rat-model of focal cerebral ischaemia. Brain Research, 1618, 205-211. https://doi.org/10.1016/j.brainres.2015.05.027

• Journal Article Type: Article
• Acceptance Date: May 22, 2015
• Online Publication Date: May 30, 2015
• Publication Date: 2015-08
• Deposit Date: Jun 5, 2015
• Publicly Available Date: May 31, 2016
• Journal: Brain Research
• Print ISSN: 0006-8993
• Electronic ISSN: 1872-6240
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 1618
• Pages: 205-211
• DOI: https://doi.org/10.1016/j.brainres.2015.05.027
• Keywords: Normobaric oxygen; Ischaemic rat model; Cerebral ischaemic–reperfusion; Apoptosis
• Public URL: http://researchrepository.napier.ac.uk/id/eprint/8562
• Publisher URL: http://dx.doi.org/10.1016/j.brainres.2015.05.027
• Contract Date: Jun 5, 2015