Neonatal androgenization-induced early endocrine–metabolic and ovary misprogramming in the female rat Luisina Ongaro a , Natalia R. Salvetti b , Andrés Giovambattista a , Eduardo Spinedi c, ⁎, Hugo H. Ortega b a Neuroendocrine Unit (IMBICE, CONICET-CICPBA), La Plata, Argentina b Institute of Veterinary Sciences (ICIVET-Litoral), UNL/CONICET, Santa Fe, Argentina c Centre for Experimental & Applied Endocrinology (CENEXA, UNLP-CONICET La Plata), Argentina abstract article info Article history: Received 24 December 2014 Received in revised form 8 March 2015 Accepted 10 March 2015 Available online 26 March 2015 Keywords: Growth Insulin Adipose tissue Leptin Ovary Steroidogenesis Aim: Androgen excess predisposes the organism to develop metabolic–endocrine and reproductive dysfunctions, among them the development of a phenotype resembling that of human Polycystic Ovary Syndrome (PCOS). Methods: We analyzed the impact of a single neonatal (5 day-old) testosterone propionate (TP; s.c. 1.25 mg/fe- male pup) dose on: a) several metabolic–endocrine activities and b) ovarian steroidogenic and granulosa cell (GC) functions and also follicular population in juvenile and adult TP and control (CT) rats. Key findings: Compared to CT rats, TP animals were characterized by: a) accelerated growth, hyperadiposity and hyperleptinemia, b) very early (pre-weaning age) vaginal opening, c) hyperinsulinemia in adult life, d) dysfunctional ovarian steroidogenesis, e) conserved GC functionality in both juveniles (in vitro) and adults (in vivo), and f) estrous cycles arrested at estrus. Finally, histological studies of the ovaries indicated that in TP (vs. CT) rats: i) primary and antral follicle frequencies were 3- and 15-fold higher and lower, respectively, in ju- veniles and ii) secondary and atretic follicle frequencies were 3- and 5-fold lower and higher, respectively, in adults. Large cystic images without corpus luteum were observed in the ovaries from adult TP rats only. Significance: Our results strongly suggest that transient neonatal hyperandrogenemia induced early misprogramming of metabolic–endocrine and ovarian (steroidogenesis/folliculogenesis) functions. Conversely, TP rats preserved their ovary GC endocrine function. Our results further support the high risk of developing ovar- ian hyperstimulation syndrome for infertile women with transient/chronic hyperandrogenemia (PCOS) subject- ed to assisted reproductive technologies. © 2015 Elsevier Inc. All rights reserved. 1. Introduction A very common cause of menstrual disturbances, chronic ano- vulation and hyperandrogenism in pre-menopausal women is Polycys- tic Ovary Syndrome (PCOS) [9,10]. Although a very large population of women at reproductive age is affected by PCOS, diagnosis of this syn- drome is still difficult for physicians [11]. Insulin resistance, with or without compensatory hyperinsulinemia, is frequently associated with PCOS [3,11,13]. Moreover, clinical and experimental studies suggest in- teraction between insulin and sex hormones in healthy subjects [2]. We previously found that androgenization in normal female rats, at either neonatal [1,19] or early post-pubertal [20] age, developed impaired in- sulin sensitivity in adulthood. We also observed a severe hypothalam- ic–pituitary–ovary (HPO) axis dysfunction in neonatally androgenized adult female rats. Indeed, on reaching adulthood, rats developed an al- tered pulsatile rhythm of gonadotropin secretion (e.g. decreased aver- age mean values, decreased FSH peak amplitude values and increased LH:FSH ratio) and impaired in vivo LHRH-stimulated LH–FSH release [23]. These abnormalities have been ascribed to a neonatal hypothalam- ic effect of transient peripheral androgen excess (hypothalamic androgenization), later resulting in infertile individuals [4]. Regarding the relation between early hyperandrogenemia and adi- pose tissue function, we previously established that 100 day-old neona- tal androgenized female rats are heavier and display greater adiposity, hyperleptinemia, impaired peripheral insulin sensitivity, and increased risk of developing dyslipidemia and cardiovascular risk [1]. In this re- gard, although physiological peripheral leptin levels are needed for nor- mal HPO axis function [21], chronic high plasma leptin concentrations (leptin resistance) are critical for consequent ovary dysfunction (e.g. anovulation) [32]. Nevertheless, it is accepted that follicle oocytes and, granulosa and theca cells express androgen receptor, a gonadotropin- regulated element [28] that must be fine-tuned by appropriate androgen stimulation to assure normal follicle development and o- vulation [28]. Tyndall et al. [24] recently investigated the effects of fetal and post-natal treatment with multiple high doses of androgen in female rats. These authors found that fetal injury (transient hyperandrogenemia in dams) failed to alter rat ovary folliculogenesis Life Sciences 130 (2015) 66–72 ⁎ Corresponding author at: CENEXA (UNLP-CONICET), Argentina. E-mail address: spinedi@cenexa.org (E. Spinedi). http://dx.doi.org/10.1016/j.lfs.2015.03.008 0024-3205/© 2015 Elsevier Inc. All rights reserved. Contents lists available at ScienceDirect Life Sciences journal homepage: www.elsevier.com/locate/lifescie