title: Plasma steroid dynamics in late- and near-term naturally and artificially conceived bovine pregnancies as elucidated by multihormone high-resolution LC-MS/MS.
abstract: The plasma levels of corticosteroids and sex steroids during pregnancy are key indicators of mammalian placental function and the onset of parturition. Steroid hormones are believed to be disturbed in pregnancies produced using assisted reproductive technologies (ARTs) due to placental dysfunction and the frequently observed lack of parturition signals. To elucidate the plasma steroid dynamics, a liquid chromatography-tandem mass spectrometry method was developed and used to determine the levels of corticosteroids (corticosterone, 11-deoxycortisol, and cortisol) and their direct precursors (progesterone and 17α-OH-progesterone) as well as sex steroids (androstenedione, estrone, estrone sulfate, testosterone, and 17β-estradiol) in bovine plasma. The levels of these 10 steroids in recipient cows carrying naturally conceived (control), in vitro fertilized (IVF), or cloned (somatic cell nuclear transfer) conceptuses were compared during late-term pregnancy (30 days before parturition), during near-term pregnancy (1 day before parturition), and on the day of parturition (day 0). Significant differences were observed among the corticosteroid levels: higher levels of corticosterone, 11-deoxycortisol, and cortisol were detected in cloned pregnancies at day 30; lower levels of corticosterone were observed in ART-derived pregnancies at days 1 and 0; and estrone and estradiol levels were higher in IVF pregnancies throughout the final development. These results suggested an upregulation of the P450C11 and P450C21 enzymes 30 days before parturition in somatic cell nuclear transfer pregnancies and an overactivation of the aromatase enzyme in IVF pregnancies. Taken together, the monitoring of multiple steroid hormones revealed that the pregnancies obtained using ART exhibited plasma steroid concentration dynamics compatible with the dysregulation of steroidogenic tissues.
authors.affiliation: Thomson Mass Spectrometry Laboratory (H.A.M.-J., R.C.S., C.R.F., M.N.E.), Institute of Chemistry, University of Campinas, Campinas, São Paulo, Brazil 13083-970; AB SCIEX of Brazil (H.A.M.-J.), São Paulo, São Paulo, Brazil 04719-002; Laboratory of Theriogenology Dr O. J. Ginther (F.L.V.P., L.A.S.), Department of Veterinary Medicine, School of Animal Sciences and Food Engineering (FZEA), University of São Paulo, Pirassununga, São Paulo, Brazil 13635-900; Laboratory of Molecular Morphophysiology and Development (A.K.T., F.V.M., F.P.), Department of Veterinary Medicine, School of Animal Sciences and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil 13635-900; Department of Production and Animal Health (R.C.S., G.P.N.), School of Veterinary Medicine, São Paulo State University, Araçatuba, São Paulo, Brazil 16050-680; and State Foundation of Agricultural Research (A.K.T.), Research Center Iwar Beckman, Hulha Negra, Rio Grande do Sul, Brazil 96400-970.
authors.forename: Helio A
authors.initials: HA
authors.lastname: Martins-Júnior
authors.forename: Fábio L V
authors.initials: FL
authors.lastname: Pinaffi
authors.forename: Rosineide C
authors.initials: RC
authors.lastname: Simas
authors.forename: Adriana K
authors.initials: AK
authors.lastname: Tarouco
authors.forename: Christina R
authors.initials: CR
authors.lastname: Ferreira
authors.forename: Luciano A
authors.initials: LA
authors.lastname: Silva
authors.forename: Guilherme P
authors.initials: GP
authors.lastname: Nogueira
authors.forename: Flávio V
authors.initials: FV
authors.lastname: Meirelles
authors.forename: Marcos N
authors.initials: MN
authors.lastname: Eberlin
authors.forename: Felipe
authors.initials: F
authors.lastname: Perecin
mesh_terms: D000305:Adrenal Cortex Hormones / Q000097:blood*; D000818:Animals; D001774:Blood Chemical Analysis / Q000379:methods*; D002417:Cattle; D002853:Chromatography, Liquid; D005260:Female; D005307:Fertilization in Vitro; D012739:Gonadal Steroid Hormones / Q000097:blood*; D053652:Nuclear Transfer Techniques; D011247:Pregnancy; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000305:Adrenal Cortex Hormones; D012739:Gonadal Steroid Hormones