Fisiología reproductiva y cambios evolutivos con la edad de la mujer

Los cambios fisiológicos con la edad, son consecuencia de cambios sistémicos generales producidos por el envejecimiento, entre los que se destacan cambios a nivel de los mecanismos de defensa relacionados con las especies reactivas del oxígeno (ROS) y alteraciones de la microcirculación. Los cambios evolutivos ováricos con la edad, se deben esencialmente a una depleción de la población folicular, la cual al disminuir por debajo de 1000 folículos, hace perder la capacidad del ovario de ciclar en forma normal, con la consiguiente disminución en los niveles de esteroides circulantes y sus efectos secundarios en los órganos efectores. Asociado a la disminución de la población folicular, se producen cambios en la calidad ovocitaria, los cuales determinan la disminución progresiva de la fertilidad en mujeres mayores de 35 años. Entre los cambios más frecuentes se observan aumento de aneuploidias, disfunciones mitocondriales, cambios de la microcirculación y disminución de la capacidad defensiva sobre las ROS, entre otros

Absence of Y chromosome microdeletions in patients with cryptorchidism and hypospadias

Microdeletions of the Y chromosome have been observed in some patients with cryptorchidism and severe defects of spermatogenesis. We investigated whether microdeletions of the Y chromosome may be present in patients with cryptorchidism and hypospadias. Peripheral blood was obtained from 20 male patients 5.8 ± 4.1 years (range: 0.4-14 years) with cryptorchidism and hypospadias for somatic DNA analysis of Y chromosome using multiplex polymerase chain reaction. These patients had no identifiable genetic syndrome, other genitourinary malformations or an abnormal karyotype. We evaluated the presence or absence of amplification using a set of 34 different sequence-tagged sites (STS) in each patient. All patients showed normal length amplifications for each of the regions evaluated, suggesting that microdeletions of the Y chromosome are not a frequent cause of hypospadias associated with cryptorchidism. © Freund Publishing House Ltd., London

The acrosome reaction-inducing activity of individual human follicular fluid samples is highly variable and is related to the steroid content

In this study, we have evaluated the relationship between the acrosome reaction-inducing activity of individual human follicular fluid samples and their steroid content. Eighteen samples of follicular fluid were obtained during egg retrieval in six patients undergoing assisted fertilization. Motile spermatozoa were incubated in modified Tyrode's medium (26 mg/ml bovine serum albumin) for 20 h at 1 x 107 cells/ml. In a single experiment, aliquots of a semen specimen were simultaneously treated with an aliquot of each follicular fluid sample. The percentage of acrosome reacted spermatozoa was determined using fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FTTC-PSA) lectin. The fluids were also analysed by radioimmunoassay to determine the levels of progesterone, 17α-hydroxy-progesterone, testosterone and oestradioh The results showed that there was a positive, highly significant correlation between the acrosome reaction-inducing activity and the progesterone level of ea

Role of the transcriptional factors FOXO1 and PPARG on gene expression of SLC2A4 in endometrial tissue from women with polycystic ovary syndrome

Fifty to seventy percent of patients with polycystic ovary syndrome (PCOS) present hyperinsulinemia. On the other hand, reports indicate that forkhead box class O 1 (FOXO1) and peroxisome proliferator-activated receptor-g (PPARG) are involved in the insulin signaling pathway, regulating the gene expression of SLC2A4 (GLUT4). The negative effect of FOXO1 over PPARG transcription disappears when FOXO1 is phosphorylated (p-FOXO1) and excluded from the nucleus, whereas PPARG can suppress gene expression of SLC2A4. Scarce knowledge is available in endometrium of women with PCOS and hyperinsulinemia (PCOSE h-Ins) about the role of these factors. We aimed to evaluate whether the endocrine and metabolic status of PCOS modify the levels of gene and protein expression of FOXO1, PPARG, and SLC2A4 in the endometria from hyperinsulinemic PCOS women compared with controls. In endometria from control (CE, n=7) or PCOSE h-Ins (n=7), we determined the subcellular location and protein levels of p-FOXO1

Nerve Growth Factor Induces Vascular Endothelial Growth Factor Expression in Granulosa Cells via a trkA Receptor/Mitogen-Activated Protein Kinase-Extracellularly Regulated Kinase 2-Dependent Pathway

Context: Acquisition of ovulatory competence by antral follicles requires development of an adequate vascular supply. Although it is well established that ovarian angiogenesis is cyclically regulated by vascular endothelial growth factor (VEGF), the factors controlling VEGF production by ovarian follicles remain largely unknown. Nerve growth factor (NGF) may be one of these factors, because NGF promotes angiogenesis and synthesis of angiogenic factors in other tissues and is produced by human granulosa cells (hGCs)

Niveles de hormona antimülleriana y factor neurotrófico derivado del cerebro como predictores de función ovárica

Infertility is now recognized as a disease by World Health Organization. It affects up to 15% of couples of childbearing age and un 4-8% of them will require high complexity assisted reproduction techniques. The delay of childbearing age involves the submission of the reproductive lifetime of the ovary. Determination of the ovarian reserve would save time and optimize resources for family planning. Antimulleriana hormone (AMH) is a marker of ovarian reserve, both quantitatively and qualitatively. It can be used in the research of premature ovarian failure, polycystic ovary syndrome (PCOS), menopause, as well as ovarian hyperstimulation syndrome (OHSS) and in vitro fertilization (IVF) poor responder patients. Brain derived neurotrophic factor (BDNF), member of growth factors family Neurotrophins, is produced by the granulosa cells and it is directly involved in the quality and timing of oocyte maturation. This review describes the reasons why the measurements of AMH and BDNF would be useful to predict the reproductive outcomes of patients undergoing IVF treatment