David K. Walmer

Effect of progestin on the ovarian epithelium of macaques : Cancer prevention through apoptosis?

Objective: The apoptosis pathway is a vital mechanism in vivo that functions to eradicate genetically damaged cells prone to malignancy. The purpose of this study was to determine whether oral contraceptives, which confer significant protection against subsequent epithelial ovarian cancer, induce apoptosis in the ovarian epithelium. Methods: Female cynomologus macaques (N = 75) were randomized to receive a diet for 35 months containing either no hormones, the oral contraceptive Triphasil (Wyeth-Ayerst Laboratories, Philadelphia, PA), the estrogenic component of Triphasil (ethinyl estradiol) alone, or the progestin component of Triphasil (levonorgestrel) alone, each administered in a cyclic fashion. At study termination, the animals underwent ovariectomy and the ovarian epithelium was examined morphologically and immunihistochemically for apoptosis. The percentage of ovarian epithelial cells undergoing apoptosis was measured in each animal and compared between the treatment groups. Results: The median percentage of ovarian epithelial cells undergoing apoptosis by treatment was control (3.8%), ethinyl estradiol (1.8%), Triphasil (14.5%), and levonorgesrel (24.9%). Compared with control and ethinyl estradiol-treated monkeys, a statistically significant increase in the proportion of apoptotic cells was noted in the ovarian epithelium of monkeys treated with the oral contraceptive Triphasil (P ≤ .01) or levonorgestrel (P < .001), with a maximal effect (six-fold) seen in the group treated with levonorgestrel alone. Conclusion: Oral contraceptive progestin induces apoptosis in the ovarian epithelium. Given the importance of the apoptosis pathway for cancer prevention, an effective chemopreventive strategy may be possible using progestins or other agents that selectively induced apoptosis in the ovarian epithelium to prevent the development of ovarian cancer.

Concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) and their associations with human semen quality measurements

A total of 256 men were studied to evaluate whether serum concentrations of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) impacted semen quality or reproductive hormones. Blood and semen were collected and analyzed for perfluorochemicals and reproductive and thyroid hormones. Semen quality was assessed using standard clinical methods. Linear and logistic modeling was performed with semen profile measurements as outcomes and PFOS and PFOA in semen and plasma as explanatory variables. Adjusting for age, abstinence, and tobacco use, there was no indication that PFOA or PFOS was significantly associated with volume, sperm concentration, percent motility, swim-up motility and concentration, and directional motility (a function of motility and modal progression). Follicle-stimulating hormone was not associated with either PFOA or PFOS. Luteinizing hormone was positively correlated with plasma PFOA and PFOS, but not semen PFOS. Important methodological concerns included the lack of multiple hormonal measurements necessary to address circadian rhythms.

Effects of Dietary Soybean Estrogens on the Reproductive Tract in Female Rats

Abstract The estrogenic actions of dietary phytoestrogens have raised concerns regarding the potential DES-like developmental effects on the female genital tract, but the growing evidence of cardioprotective benefits of dietary soybean estrogens provides the impetus to assess the effects of these compounds in adult female models of the menopause. We conducted an experiment in ovariectomized rats to determine the independent effects of dietary soybean estrogens (SBE) and the interactions of these agents with the commonly used pharmaceutical estrogen preparation (conjugated equine estrogens, CEE) in the vagina and uterus. We looked at the effects of SBE and CEE, alone and in combination, on uterine weight, body weight, vaginal cytology, uterine luminal epithelial height, and immunohistochemical staining for proliferating cell nuclear antigen (PCNA), lactoferrin (Ltf), and apoptosis. Ovariectomized rats were fed diets containing casein or soybean protein (SBE, low dose = 11.6 mg isoflavones/1800 cal; high dose = 117.8 mg/1800 cal), with no CEE, low dose CEE (0.313 mg/1800 cal), or high dose CEE (0.625 mg/1800 cal) added. In this study, SBE did not demonstrate estrogenic activity for uterine weight or vaginal cytology. We also found no estrogenic effects of these doses of SBE for PCNA, apoptosis, Ltf staining, or for LEH measurements. In addition, our results regarding the interactions of SBE and CEE do not show any evidence that the combination is additive in effect. On the contrary, the LEH response induced by low levels of CEE, was reduced by high levels of SBE. Furthermore, the Ltf response induced by CEE also was reduced by high levels of SBE. This suggests that high doses of SBE may antagonize the estrogen-agonist actions of low doses of CEE in the rat uterus. Our results in the ovariectomized rat model of menopause suggest that dietary soybean estrogens will not elicit a pattern of effects that simply recapitulates those of steroidal estrogens.

Advances in uterine leiomyoma research: conference overview, summary, and future research recommendations.

Uterine leiomyomas (fibroids, myomas) are the most common tumors occurring in the genital tract of women over 30 years of age. These benign uterine smooth-muscle tumors are estimated to be clinically significant in at least 25% of the American female population during their reproductive years. Furthermore, when thorough pathologic examination of hysterectomy specimens has been performed in patients with or without clinical history of myomatous uteri, the incidence of fibroids is 77%, suggesting that these tumors are far more prevalent than estimated by clinical cases. In spite of their high prevalence, little is known concerning the etiology or the molecular basis of their development and growth. It is well known that leiomyoma growth is regulated by ovarian steroid hormones, yet the exact molecular pathway(s) involved in tumor growth and the role of genetic susceptibility/predisposition and the environment are unclear. This article is an overview of some of the topics addressed at the conference on Womens Health and the Environment: The Next Century--Advances in Uterine Leiomyoma Research. A summary of research needs and recommendations for future research directions based on conference discussions are also presented.

Mullerian agenesis and thrombocytopenia absent radius syndrome : A case report and review of syndromes associated with mullerian agenesis

Mullerian agenesis, commonly referred to as Mayer-Rokitansky-Kuster-Hauser syndrome (MRKHS), is a congenital defect that is most commonly associated with renal and spinal malformations. It is very rare for Mullerian agenesis to be accompanied by malformations of the extremities. In this report, we describe a 22-year-old woman with Mullerian agenesis and thrombocytopenia absent radius syndrome (TARS). We also review rare syndromes associated with Mullerian anomalies, including Mullerian hypoplasia/aplasia–renal agenesis–cervicothoracic somite dysplasia (MURCS), Roberts syndrome, Bardet-Biedl syndrome (BBS), McKusick-Kaufman syndrome (MKS), Wolf-Hirschhorn syndrome, and others. The pathogenesis of these complex malformation syndromes is not well understood as a result of their sporadic occurrence. However, some of these syndromes do follow a pattern of inheritance, suggesting that they could provide insights into our understanding of their origins. Target Audience: Obstetricians & Gynecologists, Family Physicians Learning Objectives: After completion of this article, the reader should be able to review the rare congenital defects associated with Mullerian agenesis, to determine the genetic etiologies of the associated syndromes with Mullerian agenesis, and to discuss information for parental counseling related to inheritance patterns and growth and development of the affected child.

The effect of neonatal exposure to diethylstilbestrol, coumestrol, and beta-sitosterol on pituitary responsiveness and sexually dimorphic nucleus volume in the castrated adult rat.

Abstract The neonatal hormone enviroment influences the sexually differentiated patterns of development. Estrogens, derived from intracerebral aromatization, promote male pattern development of the central nervous system. The purpose of this study was to determine the effects of neonatal exposure to environmental estrogens on luteinizing hormone (LH) secretion and development of the sexually dimorphic nucleus of the medial preoptic area (SDN-POA) in castrated adult rats. Neonatal rats of both sexes received injections of either corn oil, 0.1 μg diethylstilbestrol (DES), 3 μg β-sitosterol (B1), 30 μg β-sitosterol (B2), 0.1 μg coumestrol (C1), 1 μg coumestrol (C2), or 10 μg coumestrol (C3) on Day 1-10 of life and were castrated on Day 21. Right heart catheters were placed on Day 42, and GnRH (50 ng/kg) was administered. Blood was sampled for LH at 0-, 5-, 10-, 15-, and 30-min intervals. All doses of β-sitosterol and coumestrol elicited increased basal levels of LH in females. In males, B1, B2, C2, and C3 increased basal levels of LH. The GnRH-induced LH increase was prevented in females treated with diethylstilbestrol and 10 μg of coumestrol. Males in all treatment groups exhibited GnRH-induced LH surges. The animals were sacrificed by decapitation on Day 49. Volumes of the SDN-POA of the groups were compared. Treatment with the agents did not result in significantly increased SDN volume in females; nor was there a difference in SDN size among the male groups. These data show that exposure to environmental estrogens early in development alters both postpuberal pituitary response to GnRH and basal LH secretion in females and alters only basal LH secretion in males. No significant enlargement (i.e., masculinization) of the SDN-POA was exhibited.

Human uterine leiomyoma-derived fibroblasts stimulate uterine leiomyoma cell proliferation and collagen type I production, and activate RTKs and TGF beta receptor signaling in coculture

BackgroundUterine leiomyomas (fibroids) are benign smooth muscle tumors that often contain an excessive extracellular matrix (ECM). In the present study, we investigated the interactions between human uterine leiomyoma (UtLM) cells and uterine leiomyoma-derived fibroblasts (FB), and their importance in cell growth and ECM protein production using a coculture system.ResultsWe found enhanced cell proliferation, and elevated levels of ECM collagen type I and insulin-like growth factor-binding protein-3 after coculturing. There was also increased secretion of vascular endothelial growth factor, epidermal growth factor, fibroblast growth factor-2, and platelet derived growth factor A and B in the media of UtLM cells cocultured with FB. Protein arrays revealed increased phosphorylated receptor tyrosine kinases (RTKs) of the above growth factor ligands, and immunoblots showed elevated levels of the RTK downstream effector, phospho-mitogen activated protein kinase 44/42 in cocultured UtLM cells. There was also increased secretion of transforming growth factor-beta 1 and 3, and immunoprecipitated transforming growth factor-beta receptor I from cocultured UtLM cells showed elevated phosphoserine expression. The downstream effectors phospho-small mothers against decapentaplegic -2 and -3 protein (SMAD) levels were also increased in cocultured UtLM cells. However, none of the above effects were seen in normal myometrial cells cocultured with FB. The soluble factors released by tumor-derived fibroblasts and/or UtLM cells, and activation of the growth factor receptors and their pathways stimulated the proliferation of UtLM cells and enhanced the production of ECM proteins.ConclusionsThese data support the importance of interactions between fibroid tumor cells and ECM fibroblasts in vivo, and the role of growth factors, and ECM proteins in the pathogenesis of uterine fibroids.

Optical instrument for measurement of vaginal coating thickness by drug delivery formulations

An optical device has been developed for imaging the human vaginal epithelial surfaces, and quantitatively measuring distributions of coating thickness of drug delivery formulations—such as gels—applied for prophylaxis, contraception or therapy. The device consists of a rigid endoscope contained within a 27-mm-diam hollow, polished-transparent polycarbonate tube (150mm long) with a hemispherical cap. Illumination is from a xenon arc. The device is inserted into, and remains stationary within the vagina. A custom gearing mechanism moves the endoscope relative to the tube, so that it views epithelial surfaces immediately apposing its outer surface (i.e., 150mm long by 360° azimuthal angle). Thus, with the tube fixed relative to the vagina, the endoscope sites local regions at distinct and measurable locations that span the vaginal epithelium. The returning light path is split between a video camera and photomultiplier. Excitation and emission filters in the light path enable measurement of fluorescence of t...

Advanced maternal age and perinatal outcome : Oocyte recipiency versus natural conception

Objective To compare perinatal outcome in older oocyte recipients with that in women of advanced maternal age who conceived without assisted reproductive technologies. Methods We performed a retrospective cohort study of 46 oocyte recipients and 49 women who conceived without assisted reproductive technologies. The obstetric courses in singleton and multiple gestations in the two groups of women were compared. Results Among singleton pregnancies, a comparable obstetric course was noted between the groups. Fifty percent of the oocyte recipients experienced multiple gestations, resulting in an increased risk for placenta previa, premature rupture of membranes, preterm labor and delivery, glucose intolerance of pregnancy, pregnancy-induced hypertension, and cesarean delivery. However, only the risks for pregnancy-induced hypertension and cesarean delivery were significantly increased in the pregnancies of oocyte recipients with multiple gestations. Conclusions Perinatal complications in women receiving oocyte donation may be related to their higher incidence of multiple gestation.

Transport Theory for HIV Diffusion through In Vivo Distributions of Topical Microbicide Gels

Topical microbicide products are being developed for the prevention of sexually transmitted infections. These include vaginally-applied gels that deliver anti-HIV molecules. Gels may also provide partial barriers that slow virion diffusion from semen to vulnerable epithelium, increasing the time during which anti-HIV molecules can act. To explore the barrier function of microbicide gels, we developed a deterministic mathematical model for HIV diffusion through realistic gel distributions. We applied the model to experimental data for in vivo coating distributions of two vaginal gels in women. Time required for a threshold number of virions to reach the tissue surface was used as a metric for comparing different scenarios. Results delineated how time to threshold increased with increasing gel layer thickness and with decreasing diffusion coefficient. We note that for gel layers with average thickness > approximately 100 microm, the fractional area coated, rather than the gel layer thickness, was the primary determinant of time to threshold. For gel layers < approximately 100 microm, time to threshold was brief, regardless of fractional area coated. Application of the model to vaginal coating data showed little difference in time to threshold between the two gels tested. However, the protocol after gel application (i.e., with or without simulated coitus) had a much more significant effect. This study suggests that gel distribution in layers of thickness >100 microm and fractional area coated >0.8 is critical in determining the ability of the gel to serve as a barrier to HIV diffusion.