SHORT COMMUNICATION Chilling slows anaerobic metabolism to improve anoxia tolerance of insects Leigh Boardman 1,4 • Jesper G. Sørensen 2 • Vladimı ´r Kos ˇta ´l 3 • Petr S ˇ imek 3 • John S. Terblanche 1 Received: 2 June 2016 / Accepted: 14 September 2016 / Published online: 27 September 2016 Ó Springer Science+Business Media New York 2016 Abstract Background Insects are renowned for their ability to sur- vive anoxia. Anoxia tolerance may be enhanced during chilling through metabolic suppression. Aims Here, the metabolomic response of insects to anoxia, both with and without chilling, for different durations (12–36 h) was examined to assess the potential cross-tol- erance mechanisms. Results Chilling during anoxia (cold anoxia) significantly improved survival relative to anoxia at warmer tempera- tures. Reduced intermediate metabolites and increased lactic acid, indicating a switch to anaerobic metabolism, were characteristic of larvae in anoxia. Conclusions Anoxia tolerance was correlated survival improvements after cold anoxia were correlated with a reduction in anaerobic metabolism. Keywords Anoxia Á Hypoxia Á Cold Á Lactic acid Á False codling moth 1 Introduction Periods of hypoxia (e.g. ischemia) followed by oxygen reperfusion are detrimental for humans and many mam- malian cells. However, insects are well-adapted to survive anoxia exposures, and may serve as models for studying and testing mechanisms proposed to underlie diseases or processes that are thought to be related to hypoxia or oxidative damage (e.g. ageing, cancer, sleep apnoea, ischemia) (Haddad 2006). Before insect models can become widely accepted, a thorough understanding of hypoxia tolerance, and the factors that influence hypoxia- or reperfusion-induced damage are needed. Overlapping biochemical pathways between diverse taxa rapidly expands the range of model organisms that can be studied, and can generate novel insights into classic research problems such as hypoxia tolerance and adaptations thereof. In nature, insects are routinely exposed to a wide range of stressors including temperature and hypoxia. Hypoxia can occur while living underground, at high altitudes, or frozen under ice; during different stages of development; and during periodic flooding or submersion events. Hypoxia is particularly pertinent to aquatic insects, and can have detrimental effects on growth and development for insects exposed to hypoxia during development (Harrison et al. 2006; Verberk et al. 2016). In its most extreme form, hypoxia can also be referred to as anoxia, with many insects surviving hours of 0 % oxygen, some even sur- viving for several days (Hoback 2012). Survival after hypoxic conditions is variable depending on several factors Electronic supplementary material The online version of this article (doi:10.1007/s11306-016-1119-1) contains supplementary material, which is available to authorized users. & Leigh Boardman boardman.leigh@gmail.com 1 Department of Conservation Ecology and Entomology, Centre for Invasion Biology, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa 2 Section for Genetics, Ecology & Evolution, Department of Bioscience, Aarhus University, Ny Munkegade 116, 8000 Aarhus C, Denmark 3 Institute of Entomology, Biology Centre of the Czech Academy of Sciences, C ˇ eske ´ Bude ˇjovice, Czech Republic 4 Present Address: Department of Entomology & Nematology, University of Florida, Gainesville, FL, USA 123 Metabolomics (2016) 12:176 DOI 10.1007/s11306-016-1119-1