Prenatalna hiperandrogenizacija ženki pacova testosteron undekanoatom: kognitivne, elektroencefalografske i metaboličke promene

Abstract

Razvoj ljudskog mozga podrazumeva visoko orkestriranu sekvencu događaja, koja je strogo kontrolisana kompleksnim odnosom različitih ćelijskih tipova kako u vremenu, tako i u prostoru. Započinje tokom embrionalnog perioda i do detinjstva prolazi kroz više kritičnih faza. Efekti uticaja gonadalnih hormona tokom moždanog razvoja oslikavaju se permanentnim strukturnim razlikama među polovima, a poremećaj fine homeostaze može uzrokovati pojavu psihijatrijskih i neuroloških poremećaja u odraslom dobu. Visok nivo androgena tokom gestacije (porekla majke ili fetusa), predstavlja prenatalni milje koji indukuje kardiovaskularne, metaboličke i druge bolesti u odraslom dobu. Prenatalno „programiranje“ ili modulacija prenatalnih uslova tokom „kritičnog perioda“ razvoja je preduslov za različite morfo-funkcionalne promene organskih sistema, posebno CNSa. Žene sa sindromom policističnih jajnika (PCOS) pokazuju visok nivo cirkulatornih androgena i tokom trudnoće. Egzogenom androgenizacijom ženki pacova u različitim periodima gestacije razvijeni su modeli policističnih jajnika kod potomaka. Mala težina na rođenju, povećanje telesne težine u adolescentnom periodu, povećanje visceralnog i subkutanog masnog tkiva, poremećen lipidni profil, insulinska rezistencija, poremećaj estrusnog ciklusa, predstavljaju najprominentnije morfološke i metaboličke karakteristike PCOS poremećaja. Razumevanje efekata prenatalne hiperandrogenemije veoma je važno jer predstavlja jednu od najpriminentnijih karakteristika PCOSa, čija je prevalenca kod žena reproduktivnog doba oko ∼15%. Cilj ove doktorske disertacije bio je da se ispita uticaj kasne prenatalne androgenizacije testosteron undekanoatom na: antropometrijske karakteristike, karakteristike reproduktivnog fenotipa, metabličke karakteristike, i parametre oksidativnog stresa; ponašanje i bolnu osetljivost; bihejvioralne i EEG karakteristike epilepsija izazvanih DL homocistein tiolaktonom i zastupljenost pojedinih ćelija i moždanog neurotrofnog faktora u korteksu i hipokampusu kod adultnih ženskih potomaka. U eksperimentu su korišćene ženke Wistar albino pacova. U cilju ispitivanja efekata prenatalne androgenizacije 20. dana gestacije eksperimentalnoj grupi gravidnih ženki je subkutno administriran komercijalni depo preparat testosteron undekanoata (100mg/kg, s.c.), dok je kontrolnoj grupi majki s.c. administrirano ricinusovo ulje. Drugog postnatalnog dana prebrojan je broj potomaka oba legla, a 21. postnatalnog dana izdvojeni su samo ženski potomci eksperimentalne i kontrolne grupe koji su ušli u dalji tok eksperimenta. U daljem toku eksperimenta, merena je telesna masa i unos hrane a u cilju određivanja karakteristika reproduktivnog fenotipa utvrđeno je: vreme vaginalnog otvaranja, anogenitalna distanca, i karakteristike estrusnog ciklusa. Histomorfološka analiza jajnika izvršena je na preparatima obojenim hematoksilin-eozinom. U cilju određivanja metaboličkih parametara u periodu od 60.-70. dana starosti izmerene su koncentracije glikoze i triglicerida, izveden je intraperitonealni test tolerancije na glikozu i izmerene su koncentracije testosterona, estradiola, progesterona i kortikosterona u serumima pomoću komercijalnih ELISA eseja. Parametri oksidativnog stresa određeni su u korteksu i hipokampusu metodom spektrofotometrije. Za procenu anksioznog ponašanja korišćeni su test uzdignutog krstastog lavirinta i otvoreno polje, dok je bolna osetljivosti ispitivana pomoću električnog von Frey esteziometra. U cilju analize konvulzivnog ponašanja životinjama je 75-85. dana starosti, administriran D,L-homocistein tiolakton (5,5 mmol/kg, i.p.) i posmatrani su incidneca, latenca, broj i intenzitet konvulzivnih napada...

Human brain development involves a highly orchestrated sequence of events, which is strictly controlled by complex interference between different cell types, which is time and region specific. It begins during the embryonic period and goes through several critical stages until childhood. The effects of gonadal hormones during brain development are reflected by permanent structural differences between the sexes, and disruption of fine homeostasis can cause the genesis of psychiatric and neurological disorders in adulthood. High levels of androgens during gestation (maternal or fetal origin), forms prenatal condition which can induce cardiovascular, metabolic and other diseases in adulthood. Prenatal "programming" or modulation of prenatal conditions during the "critical periods" of development is a prerequisite for various morpho-functional changes in organ systems. Women with polycystic ovary syndrome (PCOS) have high levels of circulatory androgens during pregnancy. By exogenous androgenization of female rats in different gestational periods model of polycystic ovaries have been developed in the offspring. Low birth weight, weight gain in adolescence, increase in visceral and subcutaneous adipose tissue, impaired lipid profile, insulin resistance, estrous cycle disorder, represent the most prominent morphological and metabolic characteristics of the PCOS disorder. Understanding the effects of prenatal hyperandrogenemia is very important as it represents one of the most prominent features of PCOS, with a prevalence of about ∼15% in women of reproductive age. The aims of this dissertation were to examine the effects of late prenatal androgenization with testosterone undecanoate on: anthropometric characteristics, reproductive phenotype characteristics, ovarian structure, metabolic characteristics, serum steroid hormone concentration, oxidative stress parameters; anxiety-like behavior, pain sensitivity, behavioral and EEG characteristics of epilepsies induced by DL homocysteine thiolactone; expression of markers of neuro, gliagenesis and inhibitory interneurons, in adult female offspring Female Wistar albino rats were used in the experiment. In order to examine the effects of prenatal androgenization on the 20th day of gestation, depot preparation of testosterone undecanoate (100mg / kg) was administered subcutaneously to the experimental group of pregnant females, while control group of mothers was administered castor oil (s.c.). On the second postnatal day, the number of offspring of both litters was counted, and on the 21st postnatal day only female offspring of the experimental and control group entered the further course of the experiment. Through the time of the experiment, body weight and food intake were measured and in order to determine the characteristics of the reproductive phenotype, the time of vaginal opening, anogenital distance, and the characteristics of the estrous cycle were determined. Ovarian histomorphological analysis was performed on haematoxylin-eosin stained preparations. In order to determine metabolic parameters, glucose and triglyceride concentrations were measured, an intraperitoneal glycose tolerance test was performed in the period from 60-70. days of age. Testosterone, estradiol, progesterone, and corticosterone concentrations in sera were measured using commercial ELISA assays. Oxidative stress parameters were determined in the cortex and hippocampus by spectrophotometry. An elevated plus maze test and open field were used to evaluate anxiety-like behavior, while pain sensitivity was examined using an electric von Frey estesiometer. In order to analyze convulsive behavior of animalsD, L-homocysteine thiolactone (5.5 mmol / kg, i.p.) was administered in 75-85. days old female offspring and incidence, latency, number and intensity of seizures were observed...