title: Physiological oxygen level is critical for modeling neuronal metabolism in vitro.
abstract: In vitro models are important tools for studying the mechanisms that govern neuronal responses to injury. Most neuronal culture methods employ nonphysiological conditions with regard to metabolic parameters. Standard neuronal cell culture is performed at ambient (21%) oxygen levels, whereas actual tissue oxygen levels in the mammalian brain range from 1% to 5%. In this study, we examined the consequences of oxygen level on the viability and metabolism of primary cultures of cortical neurons. Our results indicate that physiological oxygen level (5% O(2)) has a beneficial effect on cortical neuronal survival and mitochondrial function in vitro. Moreover, oxygen level affects metabolic fluxes: glucose uptake and glycolysis was enhanced at physiological oxygen level, whereas glucose oxidation and fatty acid oxidation were reduced. Adenosine monophosphate-activated protein kinase (AMPK) was more activated in 5% O(2) and appears to play a role in these metabolic effects. Inhibiting AMPK activity with compound C decreased glucose uptake, intracellular ATP level, and viability in neurons cultured in 5% O(2). These data indicate that oxygen level is an important parameter to consider when modeling neuronal responses to stress in vitro.
authors: Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
authors: Jing
authors: J
authors: Zhu
authors: Susan
authors: S
authors: Aja
authors: Eun-Kyoung
authors: EK
authors: Kim
authors: Min Jung
authors: MJ
authors: Park
authors: Santosh
authors: S
authors: Ramamurthy
authors: Junling
authors: J
authors: Jia
authors: Xueying
authors: X
authors: Hu
authors: Ping
authors: P
authors: Geng
authors: Gabriele V
authors: GV
authors: Ronnett
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000196:embryology / Q000378:metabolism / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species