Chronic prenatal ethanol exposure alters expression of central and peripheral insulin signaling molecules in adult guinea pig offspring Christine C. Dobson a , Kersh Thevasundaram a , Daniel L. Mongillo a , Andrew Winterborn b , Alison C. Holloway c , James F. Brien a, d , James N. Reynolds a, d, * a Department of Biomedical and Molecular Sciences, Pharmacology and Toxicology Graduate Program, Queen’s University, Kingston, ON, Canada K7L 3N6 b Office of the University Veterinarian, Queen’s University, Kingston, ON, Canada K7L 3N6 c Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada L8S 4K1 d Centre for Neuroscience Studies, Queen’s University, Kingston, ON, Canada K7L 3N6 Keywords: Fetal Alcohol Spectrum Disorder Insulin signaling Chronic prenatal ethanol exposure Metabolic syndrome abstract Maternal ethanol consumption during pregnancy can produce a range of teratogenic outcomes in offspring. The mechanism of ethanol teratogenicity is multi-faceted, but may involve alterations in insulin and insulin-like growth factor (IGF) signaling pathways. These pathways are not only important for metabolism, but are also critically involved in neuronal survival and plasticity, and they can be altered by chronic prenatal ethanol exposure (CPEE). The objective of this study was to test the hy- pothesis that CPEE alters expression of insulin and IGF signaling molecules in the prefrontal cortex and liver of adult guinea pig offspring. Pregnant Dunkin-Hartley-strain guinea pigs received ethanol (4 g/kg maternal body weight/day) or isocaloric-sucrose/pair-feeding (nutritional control) throughout gestation. Fasting blood glucose concentration was measured in male and female offspring at postnatal day 150 e200, followed by euthanasia, collection of prefrontal cortex and liver, and RNA extraction. IGF-1, IGF-1 receptor (IGF-1R), IGF-2, IGF-2 receptor (IGF-2R), insulin receptor substrate (IRS)-1, IRS-2, and insulin receptor (INSR) mRNA expression levels were measured in tissues using quantitative real-time PCR. The mean maternal blood ethanol concentration was 281  15 mg/dL at 1 h after the second divided dose of ethanol on GD 57. CPEE resulted in increased liver weight in adult offspring, but produced no difference in fasting blood glucose concentration compared with nutritional control. In the liver, CPEE decreased mRNA expression of IGF-1, IGF-1R, and IGF-2, and increased IRS-2 mRNA expression in male offspring only compared with nutritional control. Female CPEE offspring had decreased INSR hepatic mRNA expression compared with male CPEE offspring. In the prefrontal cortex, IRS-2 mRNA expression was increased in CPEE offspring compared with nutritional control. The data demonstrate that CPEE alters both central and peripheral expression of insulin and IGF signaling molecules at the mRNA level, which may be related to metabolic dysregulation in adult offspring. Furthermore, altered insulin and IGF signaling may be a mechanism of ethanol neurobehavioral teratogenicity. Ó 2014 Elsevier Inc. All rights reserved. Introduction Prenatal exposure to alcohol (ethanol) can produce a broad range of teratogenic outcomes to the developing fetus, including debili- tating and permanent central nervous system (CNS) dysfunction (Chudley et al., 2005). The term Fetal Alcohol Spectrum Disorder (FASD) has been coined to describe all of the structural and functional defects produced by prenatal ethanol exposure (Sokol, Delaney- Black, & Nordstrom, 2003). Recent epidemiological studies have estimated that the prevalence of FASD may be as high as 2e5% (May et al., 2009), making this a public health problem of epidemic proportion. In addition to being the leading cause of drug-induced intellectual disability (Stratton, Howe, & Battaglia, 1996), prenatal ethanol exposure may also injure other organ systems, including the heart (Gray, Denton, Cullen-McEwen, Bertram, & Moritz, 2010), lung (Sozo et al., 2011), kidney (Gray et al., 2010), and metabolic pathways (Dobson, Mongillo, Brien, et al., 2012; Elton, Pennington, Lynch, Carver, & Pennington, 2002; Shen et al., 2014; Yao & Nyomba, 2008). The range of challenges and comorbidities in individuals affected by FASD is complex, and it is estimated that the total adjusted cost of FASD in Canada is $5.3 billion annually (Stade et al., 2009). Abbreviations: FASD, Fetal Alcohol Spectrum Disorder; CPEE, chronic prenatal ethanol exposure; IGF, insulin-like growth factor; INSR, insulin receptor; IRS, insulin receptor substrate; GD, gestational day; PD, postnatalday; GTT, glucosetolerancetest. * Corresponding author. Department of Biomedical and Molecular Sciences, Queen’s University, 18 Stuart Street, Botterell Hall, Kingston, ON, Canada K7L 3N6. Tel.: þ1 613 533 6946; fax: þ1 613 533 6412. E-mail address: jnr@queensu.ca (J.N. Reynolds). Contents lists available at ScienceDirect Alcohol journal homepage: http://www.alcoholjournal.org/ 0741-8329/$ e see front matter Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.alcohol.2014.09.001 Alcohol 48 (2014) 687e693