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Study Question: Does chronic hyperandrogenemia beginning at menarche, in the absence and presence of a western-style diet (WSD), alter ovarian and uterine structure-function in young adult rhesus monkeys?Summary Answer: Phenotypic alterations in ovarian and uterine structure/function were induced by exogenous testosterone (T), and compounded in the presence of a WSD (T+WSD).What Is Known Already: Hyperandrogenemia is a well-established component of PCOS and is observed in adolescent girls, indicating a potential pubertal onset of disease symptoms. Obesity is often associated with hyperandrogenemia and it is hypothesized that metabolic dysfunction exacerbates PCOS symptoms.Study Design, Size, Duration: Macaque females (n = 40) near the onset of menarche (~2.5 years of age) were assigned to a 2 by 2 factorial cohort design. Effects on reproductive characteristics were evaluated after 3 years of treatment.Participants/materials, Setting, Methods: Rhesus macaques (Macaca mulatta) were fed either a normal balanced diet (n = 20) or a WSD (n = 20). Additionally, implants containing cholesterol (n = 20) or T (n = 20) were implanted subcutaneously to elevate serum T approximately 5-fold. This resulted in treatment groups of controls (C), T, WSD and T+WSD (n = 10/group). Vaginal swabbing was performed daily to detect menses. After 3 years of treatment, daily serum samples from one menstrual cycle were assayed for hormone levels. Ovarian structure was evaluated in the early follicular phase by 3D/4D ultrasound. Uterine endometrial size and ovarian/luteal vascular function was also evaluated in subgroups (n = 6/group) in the late follicular and mid-luteal phases by 3D/4D ultrasound and contrast-enhanced ultrasound, respectively. Expression of steroid hormone receptors and markers of decidualization and endometrial receptivity were assessed in endometrial biopsies at mid-luteal phase.Main Results and the Role Of Chance: Approximately 90% of menstrual cycles appeared ovulatory with no differences in frequency or duration between groups. Serum estradiol (E2) levels during the early follicular phase were greatest in the T alone group, but reduced in T+WSD (P < 0.02). Serum LH was elevated in the T group (P < 0.04); however, there were no differences among groups in FSH levels (P > 0.13). Ovarian size at menses tended to be greater in the WSD groups (P < 0.07) and antral follicles ≥1 mm were more numerous in the T+WSD group (P < 0.05). Also, females in T and T+WSD groups displayed polycystic ovarian morphology (PCOM) at greater frequency than C or WSD groups (P < 0.01). Progesterone (P4) levels during the luteal phase were reduced in the T+WSD group compared to C and T groups (P < 0.05). Blood volume (BV) and vascular flow (VF) within the corpus luteum was reduced in all treatment groups compared to C (P < 0.01, P = 0.03), with the WSD alone group displaying the slowest BV and VF (P < 0.05). C and WSD groups displayed endometrial glands at mid-luteal phase with low estrogen receptor 1 (ESR1) and progesterone receptor (PGR) mRNA and immunohistochemical staining in the functionalis zone, but appreciable PGR in the stroma. In contrast, T and T+WSD treatment resulted in glands with less secretory morphology, high ESR1 expression in the glandular epithelium and low PGR in the stroma. Endometrial levels of TIMP3 and MMP26 mRNA and immunostaining were also decreased in the T and T+WSD groups, whereas AR expression was unchanged.Large Scale Data: None.Limitations, Reasons For Caution: Females are young adults, so effects could change as they reach prime reproductive age. The T level generated for hyperandrogenemia may be somewhat greater than the 3-4-fold increase observed in adolescent girls, but markedly less than those observed in male monkeys or adolescent boys.Wider Implications Of the Findings: Alterations to ovarian and uterine structure-function observed in T and, in particular, T+WSD-treated female macaques are consistent with some of the features observed in women diagnosed with polycystic ovary syndrome (PCOS), and suggest impaired fertility.Study Funding/competing Interest(s): Research reported in this publication was supported by the Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD) of the National Institutes of Health (NIH) under Award Number P50HD071836 (to RLS). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. Additional funding was provided by Office of the Director, NIH under Award Number P51OD011092 (Support for National Primate Research Center). Authors declare no competing interests. [ABSTRACT FROM AUTHOR]

Background The objective of the current study was to determine changes to vascular parameters of nonhuman primate dominant ovarian structures by dynamic contrast-enhanced ultrasound ( DCE- US). Materials and Methods Dynamic contrast-enhanced ultrasound with intravenous microbubble infusion was performed on the rhesus macaque ovary bearing the pre-ovulatory follicle and corpus luteum ( CL) sequentially during the natural luteal phase (n = 8) and Gn RH antagonist (antide)-induced luteal regression (n = 6). Results Changes in luteal blood volume ( BV) and vascular flow ( VF) were observed between stages of the luteal phase Luteal BV was highest in early stage CL, before decreasing 2.5-fold in late stage CL ( P < 0.06); in contrast, luteal VF peaked at mid luteal stage ( P < 0.01). Two females identified with luteal insufficiency trended toward lower peak BV, compared to typical CLs. Another female was identified with a luteal cyst on the contralateral ovary, and a CL that regressed before P levels declined. After 72 hours of antide exposure, BV was reduced 2.3-fold ( P = 0.03). Conclusions DCE-US provides a sensitive, non-invasive measurement of the dynamics of blood volume and flow in dominant ovarian structures. [ABSTRACT FROM AUTHOR]

Background: Epithelial ovarian cancer (EOC) risk correlates strongly with the number of ovulations that a woman experiences. The primary source of EOC in women is the ovarian surface epithelium (OSE). Mechanistic studies on the etiology of OSE transformation to EOC cannot be realistically performed in women. Selecting a suitable animal model to investigate the normal OSE in the context of ovulation should be guided by the model's reproductive similarities to women in natural features that are thought to contribute to EOC risk.Methods: We selected the non-human primate, rhesus macaque, as a surrogate to study the normal OSE during the natural menstrual cycle. We investigated OSE morphology and marker expression, plus cell proliferation and death in relation to menstrual cycle stage and ovulation.Results: OSE cells displayed a morphological range from squamous to columnar. Cycle-independent parameters and cycle-dependent changes were observed for OSE histology, steroid receptor expression, cell death, DNA repair and cell adhesion. Contrary to findings in non-primates, primate OSE cells were not manifestly cleared from the site of ovulation, nor were proliferation rates affected by ovulation or stage of the menstrual cycle. DNA repair proteins were more highly expressed in OSE than in other ovarian cells.Conclusions: This study identifies significant differences between primate and non-primate OSE. In contrast to established views, ovulation-induced death and proliferation are not indicated as prominent contributors to EOC risk, but disruption of OSE cadherin-mediated adhesion may be, as could the loss of ovary-mediated chronic suppression of proliferation and elevation of DNA repair potential. [ABSTRACT FROM AUTHOR]

Objective: To compare LH, FSH, P, and E(2) levels obtained from blood spot vs. plasma (single-visit study) and to determine whether blood spots can document circulating hormone levels during ovulatory cycles (menstrual-cycle study).Design: Cross-sectional study.Setting: Academic center.Patient(s): Women 18-35 years of age with regular menstrual cycles and no recent use of hormonal contraception.Intervention(s): Women contributed both a blood spot sample from a finger-stick and a plasma sample through venipuncture on a random day within their menstrual cycle (n = 100, single study visit). Five additional women were followed for an entire menstrual cycle with biweekly venipuncture and daily self-collected blood spot sampling. Samples were analyzed for FSH, LH, P, and E(2).Main Outcome Measure(s): Correlation between blood spot and plasma levels.Result(s): Significant positive correlations were found between the blood spot and plasma samples in the single-visit study (r(2): FSH, 0.91; LH, 0.93; P, 0.83; and E(2,) 0.70). Two of the 5 menstrual-cycle study women had ovulatory cycles based on P levels (>3 ng/mL) and an LH surge. Daily blood spot sampling was better able to document hormonal changes than biweekly venipuncture.Conclusion(s): Blood spot monitoring of FSH, LH, P, and, to a lesser extent, E(2), appears to be as valid as traditional plasma assays for clinical research and care. [ABSTRACT FROM AUTHOR]

Molecular targets of rapid non-genomic steroid actions are not well known compared to those of the classical transcription pathway, but ion channels have recently been identified to be steroid-sensitive. Especially, in the ovary, the very organ producing high amounts of sex steroids, their rapid actions are not well examined. We now identified a yet unknown target for sex steroids, a voltage-dependent K+ channel (Kv4.2) that contributes to a transient outward K+ current (IA) in human granulosa cells (GCs). Sex steroid hormones at concentrations typical for the ovary (1 µM) blocked Kv4.2 thereby attenuating IA by about 25% within seconds. We also found both Kv4.2 (KCND2) mRNA and protein in endocrine cells of the human and rhesus macaque ovary, emphasizing the physiological relevance of this channel. Therefore, we propose a role as fast-responding steroid sensor for the Kv4.2 channel. The direct regulation of K+ channel activity by sex steroids might represent a yet unknown mechanism of rapid steroid action in close proximity to the site of steroid production in the primate ovary. Our data might also be important for Kv4 channels in the brain and the cardiovascular system where rapid steroid effects are discussed in the context of prevention of cell death. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Objective: To determine whether angiopoietin (ANGPT)-1 and -2 are detectable in the circulation of nonhuman primates and women and whether these levels fluctuate in association with ovarian activity.Design: Prospective.Setting: National Primate Research Center, medical center, and infertility clinic.Patient(s): Adult female rhesus monkeys; 15 women donating oocytes for infertility treatment.Intervention(s): Controlled ovarian stimulation with gonadotropins, removal of the corpus luteum and ovaries, oocyte retrieval, and ET.Main Outcome Measure(s): Circulating levels of ANGPT-1 and ANGPT-2.Result(s): Serum ANGPT-1 and ANGPT-2 levels were detectable and invariant in maintaining an ANGPT-1 to -2 ratio >1 in [1] macaques over the course of the natural menstrual cycle, during a controlled ovulation protocol, and after removal of the corpus luteum or ovaries and [2] women undergoing controlled ovarian simulation. In contrast, the ANGPT-1 to -2 ratio was markedly decreased (<<1) at mid-to-late gestation in macaques and in the follicular fluid of women undergoing controlled ovarian simulation because of increased levels of ANGPT-2.Conclusion(s): The ovary and its dominant structures are not major contributors to circulating levels of ANGPT-1 or ANGPT-2. The physiologic importance of the rising levels of ANGPT-2 after the luteal-placental shift in pregnancy is unknown. [ABSTRACT FROM AUTHOR]

Continual administration of low doses of the antiprogestin ZK 137 316 permits ovarian/menstrual cyclicity, but prevents pregnancy in female rhesus monkeys. The sites of contraceptive action remain unknown. This study determined whether chronic, low-dose antiprogestin exposure during follicular development impairs oocyte maturation in vivo, as well as fertilization and preimplantation embryogenesis in vitro. Adult, female rhesus monkeys exhibiting normal menstrual cycles received vehicle (n=9) or 0.03 mg ZK 137 316 (n=8)/kg body weight i.m. daily for 3 months. Controlled ovarian stimulation with recombinant gonadotropins was initiated in the 3rd month. Oocytes collected from preovulatory follicles were evaluated for nuclear maturity and inseminated in vitro. Preimplantation embryonic development was monitored in vitro. The total number of oocytes and percentage collected at each nuclear stage were similar in both groups. More (P<0.05) atretic oocytes were recovered following antiprogestin relative to vehicle treatment. Fertilization rates and percentages of embryos that progressed to the morula stage were similar between groups, but antiprogestin-treated females exhibited less (P<0.05) normal cleavage. Embryonic development was accelerated by 1 day (P<0.05) from the 16-cell to the morula stage in the antiprogestin group relative to vehicle. Despite this, the majority of embryos became blastocysts within 6 days in vitro in the antiprogestin group, but fewer expanded (P=0.09) and hatched (P<0.05) compared to vehicle. During in vivo treatment with chronic, low-dose antiprogestin, oocytes retained their ability to resume and complete meiosis as well as fertilize following insemination in vitro. However, preimplantation embryogenesis in vitro was impaired, particularly during the later stages of blastocyst development. Thus, antiprogestin exposure during follicular development altered oocyte functions that are critical for normal preimplantation embryogenesis; this may contribute to pregnancy prevention. [Copyright &y& Elsevier]

Objective: To examine the small antral follicle (SAF) cohort in ovaries of adult rhesus monkeys after consumption of a Western-style diet (WSD), with or without chronically elevated androgen levels since before puberty.Design: Cholesterol or T (n = 6 per group) implants were placed SC in female rhesus macaques beginning at 1 year of age (prepubertal), with addition of a WSD (high fat/fructose) at 5.5 years (menarche approximately 2.6 years). Ovaries were collected at 7 years of age. One ovary per female was embedded in paraffin for morphologic and immunohistochemical analyses. The SAFs (<2.5 mm) were dissected from the other ovary obtained at or near menses in a subgroup of females (n = 3 per group) and processed for microarray analyses of the SAF transcriptome. Ovaries of adult monkeys consuming a standard macaque diet (low in fats and sugars) were obtained at similar stages of the menstrual cycle and used as controls for all analyses.Setting: Primate research center.Animal(s): Adult, female rhesus monkeys (Macaca mulatta).Intervention(s): None.Main Outcome Measures: Histologic analyses, SAF counts and morphology, protein localization and abundance in SAFs, transcriptome in SAFs (messenger RNAs [mRNAs]).Result(s): Compared with controls, consumption of a WSD, with and without T treatment, increased the numbers of SAFs per ovary, owing to the presence of more atretic follicles. Numbers of granulosa cells expressing cellular proliferation markers (pRb and pH3) was greater in healthy SAFs, whereas numbers of cells expressing the cell cycle inhibitor (p21) was higher in atretic SAFs. Intense CYP17A1 staining was observed in the theca cells of SAFs from WSD with or without T groups, compared with controls. Microarray analyses of the transcriptome in SAFs isolated from WSD and WSD plus T-treated females and controls consuming a standard diet identified 1,944 genes whose mRNA levels changed twofold or more among the three groups. Further analyses identified several gene pathways altered by WSD and/or WSD plus T associated with steroid, carbohydrate, and lipid metabolism, plus ovarian processes. Alterations in levels of several SAF mRNAs are similar to those observed in follicular cells from women with polycystic ovary syndrome.Conclusion(s): These data indicate that consumption of a WSD high in fats and sugars in the presence and absence of chronically elevated T alters the structure and function of SAFs within primate ovaries. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of slow cryopreservation on the morphology and function of primate primordial follicles within ovarian tissue slices.Design: Fresh monkey ovarian tissue was frozen by slow cryopreservation and thawed for analysis of morphologic and functional parameters.Setting: University-affiliated laboratory.Animals: Rhesus monkey ovarian tissue.Intervention(s): None.Main Outcome Measure(s): Histologic analysis, follicle counting, assessment of protein abundance and localization.Result(s): After freezing and thawing, 89% of the primordial follicles maintained their laminar-based architecture, with sizes close to those of fresh fixed follicles. Molecular markers of early follicle health (activin subunits and the phosphorylated form of the signaling protein Smad2 [pSmad2]) were present in fresh and frozen-thawed primordial follicles. Stroma cells, but not follicles, had a higher level of TUNEL staining. Granulosa cells within the follicles of frozen-thawed ovarian tissue cultured for 48 hours had the capacity to proliferate and sustained expression of the activin subunits and nuclear pSmad2.Conclusion(s): This study provides evidence that markers of early follicle growth and development are preserved after slow cryopreservation and thaw, with little effect on follicle morphology and function. [ABSTRACT FROM AUTHOR]