title: Reproductive alterations in hyperinsulinemic but normoandrogenic MSG obese female rats.
abstract: Obesity and metabolic syndrome are the common causes of reproductive and fertility disorders in women. In particular, polycystic ovary syndrome, which is clinically characterized by hyperandrogenism, oligo/anovulation, and polycystic ovarian morphology, has been increasingly associated with metabolic disorders. However, given the broad interplay between metabolic and reproductive functions, this remains a field of intense research. In this study, we investigated the effect of monosodium l-glutamate (MSG)-induced obesity on reproductive biology of female rats. Newborn female rats were subcutaneously injected with MSG (4g/kg/day) or equiosmolar saline (CTR) each 2 days up to postnatal day (pnd) 10. On pnd 60, estrous cycle was evaluated using vaginal smears twice a day for 15 days, which showed MSG rats to be oligocyclic. Thereafter, animals were killed on estrous phase for blood and tissue collection. MSG rats had increased body mass, accumulation of retroperitoneal and visceral fat pads, and visceral adipocyte hypertrophy compared with CTR rats. MSG rats were also dyslipidemic and hyperinsulinemic but were normoglycemic and normoandrogenic. Ovarian morphology analysis showed that MSG rats had a two-fold decrease in oocyte count but a six-fold increase on ovarian follicular cysts, along with a higher number of total primordial and atretic follicles. Moreover, MSG rats had a four-fold increase in anti-Müllerian hormone immunohistochemical staining on antral follicles. Taken together, data presented here characterize MSG obesity as a unique model to study the metabolic pathways underlying reproductive disorders in the absence of overactivated hypothalamic-pituitary-gonadal axis.
authors.affiliation: Department of Physiological SciencesFederal University of Maranhão, São Luís, Maranhão, Brazil.
authors.forename: Renato Simões
authors.initials: RS
authors.lastname: Gaspar
authors.affiliation: Department of Physiological SciencesFederal University of Maranhão, São Luís, Maranhão, Brazil.
authors.forename: Renata Ohana Alves
authors.initials: RO
authors.lastname: Benevides
authors.affiliation: Department of Physiological SciencesFederal University of Maranhão, São Luís, Maranhão, Brazil.
authors.forename: João Lucas de Lima
authors.initials: JL
authors.lastname: Fontelles
authors.affiliation: Department of Physiological SciencesFederal University of Maranhão, São Luís, Maranhão, Brazil.
authors.forename: Caroline Castro
authors.initials: CC
authors.lastname: Vale
authors.affiliation: Department of Physiological SciencesFederal University of Maranhão, São Luís, Maranhão, Brazil.
authors.forename: Lucas Martins
authors.initials: LM
authors.lastname: França
authors.affiliation: Department of Physiological SciencesFederal University of Maranhão, São Luís, Maranhão, Brazil Department of PhysiologySchool of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Paulo de Tarso Silva
authors.initials: Pde T
authors.lastname: Barros
authors.affiliation: Department of Physiological SciencesFederal University of Maranhão, São Luís, Maranhão, Brazil marcuspaes@ufma.br.
authors.forename: Antonio Marcus de Andrade
authors.initials: AM
authors.lastname: Paes
mesh_terms: D000728:Androgens / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D054304:Anti-Mullerian Hormone / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D006946:Hyperinsulinism / Q000139:chemically induced / Q000503:physiopathology; D053858:Metabolic Networks and Pathways / Q000187:drug effects; D024821:Metabolic Syndrome / Q000139:chemically induced / Q000503:physiopathology; D009765:Obesity / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology*; D010053:Ovary / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D011085:Polycystic Ovary Syndrome / Q000139:chemically induced / Q000503:physiopathology; D051381:Rats; D017208:Rats, Wistar; D012098:Reproduction / Q000187:drug effects; D012970:Sodium Glutamate / Q000633:toxicity*
chemical_list: D000728:Androgens; D054304:Anti-Mullerian Hormone; D012970:Sodium Glutamate
keywords: hypothalamic obesity; metabolic syndrome; monosodium l-glutamate; proliferation; reproductive disorders