The Sperm Journey from the Cervix to the Site of Fertilization; a Predetermined Encounter [Imago Homini 24: 71-82]
Author: Vigil P., Valdés-Undurraga I., Del Río J.P., and Serrano F.G. (2017)
Sperm interact with various microenvironments, generating conditions for sperm capacitation and acrosome reaction in the right place and time. Such events are highly synchronized to ensure fertilization. This review describes and analyzes the various changes sperm experience during transport through the female genital tract: the infuence of cervical, endometrial and oviductal secretions, interaction with the epithelium, and hormonal effects on sperm. Molecules in the microenvironments with which sperm interact include hormones, neurotransmitters, and other metabolites. Physiological events of gamete membrane fusion should be considered by basic and ap- plied researchers working in reproductive biology
Influence of sex steroid hormones on the adolescent brain and behavior: An update [The Linacre Quarterly, 83(3), 308-329]
Author: Pilar Vigil, Juan Pablo del Río, Ba ́rbara Carrera, Florencia C. Ara ́nguiz, Hernán Rioseco & Manuel E. Cortés (2016)
The effect of steroid hormones on the development of the adolescent brain, and therefore, on adolescent behavior, is noticeable. This review presents their main activational and organizational effects. During the transition from puberty to adolescence, organizational phenomena triggered by steroids structurally affect the remodeling of brain circuits. Later in adulthood, these changes will be reflected in behavioral responses to such hormones. Adolescence can then be seen as a fundamental “organizational window” during which sex steroids and other hormones and com- pounds play relevant roles. The understanding of the relationship between adolescent behavior and the way hormones influence brain development help understand some psychological disorders.
The Importance of Fertility Awareness in the Assessment of a Woman’s Health: A Review [The Linacre Quarterly, 79(4), 426–450]
Author: Vigil, P., Blackwell, L. F., & Cortés, M. E. (2012)
Fertility awareness constitutes fundamental knowledge for every woman and is an important tool for health professionals. The objective of this review is to show how fertility awareness can be useful in the assessment of a woman's health. The main techniques for detecting ovulation are explained, and then the events that characterize a normal menstrual cycle are discussed. The relevance of cervical mucus from the perspective of female fertility is highlighted. Finally, the usefulness of fertility awareness 1) to identify fertile and infertile periods, 2) to help to detect several pathologies, and 3) in regards to how it exerts an important role in the success of programs in education for affectivity and sexuality are discussed.
Self-identification of the clinical fertile window and the ovulation period [Fertility & Sterility, 103(5), 1319–1325]
Author: Ecochard, R., Duterque, O., Leiva, R., Bouchard, T., & Vigil, P. (2015)
The self-identification of the biological fertile window by the observation of any type of cervical mucus provides 100% sensitivity but poor specificity, yielding a clinical fertile window of 11 days. However, the identification of the biological fertile window by peak mucus (defined as clear, slippery, or stretchy mucus related to estrogen) yielded 96% sensitivity and improved specificity. The appearance of the peak mucus preceded the biological fertile window in less than 10% of the cycles. Likewise, this type of mucus identified the ovulation window with 88% sensitivity.
Physiological action of oestradiol on the acrosome reaction in human spermatozoa. [Andrologia, 40, 146–151]
Author: Vigil, P., Toro, A., & Godoy, A. (2007)
The acrosome is a secretory vesicle located in the sperm head. The acrosome reaction consists in the fusion of the sperm plasma membrane with the external acrosomal membrane. It has been observed that this reaction does not take place in spermatozoa incubated in cervical mucus, hydrogel that contains high concentrations of oestradiol in the peri-ovulatory period. The objective of the present study was to analyse the influence of oestradiol on the acrosome reaction in human spermatozoa to evaluate the possible inhibitory effect of this hormone. Spermatozoa were incubated in progesterone (10.1 nmol l−1); oestradiol plus progesterone (oestradiol at 840 pmol l−1 and progesterone at 10.1 nmol l−1), oestradiol (840 pmol l−1) and control (without steroidal hormones) for 30 min, 60 min, 240 min and 24 h. The acrosome reaction was evaluated by stain with Hoechst 33258 and fluorescein isothiocyanate-conjugated Pisum sativum agglutinin lectin. Progesterone-incubated spermatozoa showed the highest percentage of acrosome reaction (P <0.05). Spermatozoa incubated with oestradiol and oestradiol plus progesterone showed the lowest percentage of acrosome reaction. The present study demonstrates the inhibitory role of oestradiol on the acrosome reaction, stimulated by progesterone in human spermatozoa under physiological conditions.
Scanning electron and light microscopy study of the cervical mucus in women with polycystic ovary syndrome [Journal of Electron Microscopy, 58(1), 21–27]
Author: Vigil, P., Cortés, M. E., Zuñiga, A., Riquelme, J., & Ceric, F. (2009).
Two types of cervical mucus are recognized, oestrogenic and gestagenic. These are constituted by different subtypes, and their characteristics change depending on variations in the hormonal levels and on the existence of several pathologies. Our aim was to identify the ultrastructure and crystallization characteristics of the cervical mucus in women suffering from polycystic ovary syndrome, and to compare these characteristics with those of normal control women. Cervical mucus samples were taken from 10 women, 4 control group women (with normal ovulatory menstrual cycles) and 6 suffering from polycystic ovary syndrome (2 with ovulatory and 4 with anovulatory cycles). This mucus was characterized according to its ultrastructure and crystallization. The type of mucus obtained was related to the levels of oestradiol and progesterone present when the samples were taken. As regards mucus ultrastructure, differences were found between the control women and those with polycystic ovary syndrome and anovulatory menstrual cycles. Such variations were evident in the type of mesh and the average diameter of the mucus pores. Mucus crystallization in control women showed the usual oestrogenic disposition: fern-like (L, P2), rectilinear (S) or a hexagonal structure (P6). On the other hand, in women with polycystic ovary syndrome, indefinite mucus crystallizations were found, as well as crystallization patches resembling oestrogenic and gestagenic-like mucus. This study shows that the ultrastructure and crystallization characteristics of the cervical mucus in polycystic ovary syndrome women are different from those of control women. The latter would be dependent on their levels of oestradiol and progesterone.
Modulation of spermatozoon acrosome reaction [Biological Research, 44, 151–159]
Author: Vigil, P., Orellana, R. F., & Cortés, M. E. (2011)
Spermatozoon acrosome reaction is an exocytotic event of the utmost importance for the development of mammalian fertilisation. Current evidence shows that the triggering of the acrosome reaction (AR) could be regulated by the action of diverse compounds, namely, metabolites, neurotransmitters and hormones. The aim of the present review is to describe the modulating effects of several compounds that have been classified as inductors or inhibitors of acrosome reaction. Among AR inductors, it is necessary to mention progesterone, angiotensin II, atrial natriuretic peptide, cathecolamines, insulin, leptin, relaxin and other hormones. Regarding the inhibitors, oestradiol and epidermal growth factor are among the substances that retard AR. It is worth mentioning that gamma-aminobutyric acid, a neurotransmitter known to be an inhibitor in the central nervous system, has been shown to induce AR. The multiple hormones located in the fluids of the female reproductive tract are also likely to act as subtle regulators of AR, constituting a fundamental aspect for the development of successful fertilisation. Finally, it is necessary to emphasise that the study of regulation exerted by hormones and other compounds on AR is essential for further understanding of mammalian reproductive biology, especially spermatozoon physiology.