Research Report Brief anoxia preconditioning and HIF prolyl-hydroxylase inhibition enhances neuronal resistance in organotypic hippocampal slices on model of ischemic damage Iryna Lushnikova a , Maxim Orlovsky a, ⁎ , Victor Dosenko b , Anastasiia Maistrenko a , Galina Skibo a a Department of Cytology, Bogomoletz Institute of Physiology, National Academy of Sciences, Ukraine b Department of General Pathophysiology, Bogomoletz Institute of Physiology, National Academy of Sciences, Ukraine ARTICLE INFO ABSTRACT Article history: Accepted 14 February 2011 Available online 19 February 2011 It is well known that a brief anoxia or hypoxia episodes can render brain resistant to a subsequent ischemia. Recent investigations indicate that mechanisms of such stimulated endogenous neuroprotection are related to the family of hypoxia-inducible factors (HIF), however there are still little data available on the role of HIF family members in hippocampus—a brain structure, highly sensitive to oxygen deficiency. We have used the model of cultured hippocampal slices and single-cell quantitative RT-PCR to study HIF-1α and HIF-3α mRNA expression following triple 5-min mild anoxia, 30-min oxygen-glucose deprivation and their combination. We also tested the effects of HIF prolyl-hydroxylase inhibition with 2,4-pyridinedicarboxylic acid diethyl ester pre-treatment followed by a 30-min oxygen-glucose deprivation. It was found that neuronal damage induced by oxygen- glucose deprivation was accompanied by a significant decrease in both HIF-1α and HIF-3α mRNA levels in CA1 but not CA3 neurons. Anoxia preconditioning did not affect cell viability and HIF mRNA levels but applied before oxygen-glucose deprivation prevented neuronal damage and suppression of HIF-1α and HIF-3α mRNA expression. It was also found that effects of the prolyl-hydroxylase inhibitor were similar to anoxia preconditioning. These results suggest that anoxia preconditioning increases anti-ischemic neuronal resistance which to a certain extent correlates with the changes of HIF-1α and HIF-3α expression. © 2011 Elsevier B.V. All rights reserved. Keywords: Organotypic hippocampal culture Anoxia preconditioning Oxygen-glucose deprivation Neuroprotection Hypoxia-inducible factors (HIF) 1. Introduction Ischemia and hypoxia may induce extensive injury in hippo- campus that results in an impairment of behavior, stress response, learning and memory (Balduini et al., 2000, Lushni- kova et al., 2004, Kovalenko et al., 2006). Endogenous mecha- nisms of neuroprotection during the recent past attract a growing number of investigations and it is now well established that brief sublethal anoxia episodes can render neurons resistant against subsequent longer or more severe anoxia BRAIN RESEARCH 1386 (2011) 175 – 183 ⁎ Corresponding author at: Bogomoletz str. 4, Kiev, 01024, Ukraine. Fax: +380 44 256 20 00. E-mail address: dr.orlovsky@gmail.com (M. Orlovsky). Abbreviations: HIF, Hypoxia-induced factor; OGD, Oxygen-glucose deprivation; APC, Anoxia preconditioning; DPD, 2,4-pyridinedicar- boxylic acid diethyl ester; qRT-PCR, quantitative reverse-transcription polymerase chain reaction; PI, propidium iodide 0006-8993/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.brainres.2011.02.033 available at www.sciencedirect.com www.elsevier.com/locate/brainres