Sperm Incubation in Biggers-Whitten-Whittingham Medium Induces Capacitation-Related Changes in the Lizard Sceloporus torquatus.

Sperm capacitation involves biochemical and physiological changes that enable sperm to fertilize the oocyte. It can be induced in vitro under controlled conditions that simulate the environment of the oviduct. While extensively studied in mammals, its approach in lizards remains absent. Understanding the mechanisms that ensure reproduction is essential for advancing the implementation of assisted reproductive technologies in this group. We aimed to perform a sperm analysis to determine if capacitation-related changes were induced after incubation with capacitating media. Fifteen males of Sceloporus torquatus were collected during the early stage of the reproductive season. The sperm were isolated from the seminal plasma and then diluted up to a volume of 150 µL using BWW medium to incubate with 5% CO2 at 30 °C for a maximum duration of 3 h. A fraction was retrieved hourly for ongoing sperm assessment. The sperm analysis included assessments of its motility, viability, the capacitation status using the chlortetracycline (CTC) assay, and the acrosome integrity with the lectin binding assay to detect changes during incubation. We found that total motility was maintained up to 2 h post incubation, after which it decreased. However, sperm viability remained constant. From that moment on, we observed a transition to a deeper and less symmetrical flagellar bending in many spermatozoa. The CTC assay indicated a reduction in the percentage of sperm showing the full (F) pattern and an increase in those exhibiting the capacitated (B) and reactive (RA) patterns, accompanied by an elevation in the percentage of damaged acrosomes as revealed by the lectin binding assay. In mammals, these changes are often associated with sperm capacitation. Our observations support the notion that this process may also occur in saurian. While sperm analysis is a valuable method for assessing certain functional changes, additional approaches are required to validate this process.

Bibliometric analysis of peer-reviewed literature on perinatal depression in Mexico / Análisis bibliométrico de la literatura revisada por pares sobre depresión perinatal en México

Abstract Background Perinatal depression (PND) is a clinical disease developed in any stage during the pregnancy and postpartum period with serious health and economic implications. Objective The aim of this work was to analyze via bibliometrics indicators Mexico's production on PND to provide a view of the academic landscape and a comprehensive reference for subsequent research in the country. Method The Scopus and Web of Science (WoS) databases were used to perform a search for peer reviewed papers related to PND in México. The search was made following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The extracted data were processed with VOS Viewer to examine link strength and clusters associations of diverse bibliometrics variables. Results A total of 132 records were retrieved and we included 70 studies in the bibliometric analysis after application of the exclusion criteria. The authors with more papers were Navarrete L., and Asunción Lara M. The institutions with more papers were the National Institute of Perinatology, Ramón de la Fuente National Institute of Psychiatry, and National Institute of Public Health of Mexico. A diminution of the research considered in PND is observed in the last two years. Four keyword clusters were identified related to PND: symptoms, prevalence, pregnancy. Discussion and conclusion The scarce literature concerning PND in Mexico compared with other countries could be due the limited collaboration between the health institutes. An urgent need to increase research on PND in Mexico is evident to be applicable in the management of resources in the healthcare system.

Resumen Antecedentes La depresión perinatal (PND) es una enfermedad clínica que se desarrolla en cualquier etapa del embarazo y posparto con graves implicaciones sanitarias y económicas. Objetivo El objetivo de este trabajo fue analizar a través de indicadores bibliométricos la producción de México sobre PND, para brindar una visión del panorama académico y un referente integral para investigaciones posteriores en el país. Método Se utilizaron las bases de datos Scopus y Web of Science (WoS) para realizar una búsqueda de artículos revisados por pares relacionados con la PND en México. La búsqueda se realizó siguiendo los elementos de informes preferidos para revisiones sistemáticas y metaanálisis (PRISMA). Los datos extraídos se procesaron con VOS Viewer para examinar la fuerza de los enlaces y las asociaciones de grupos de diversas variables bibliométricas. Resultados Se recuperaron un total de 132 registros y se incluyeron 70 estudios en el análisis bibliométrico después de la aplicación de los criterios de exclusión. Los autores con más artículos fueron Navarrete L. y Asunción Lara M. Las instituciones con más artículos fueron el Instituto Nacional de Perinatología, el Instituto Nacional de Psiquiatría Ramón de la Fuente y el Instituto Nacional de Salud Pública de México. Se observa una disminución de las investigaciones consideradas en el PND en los últimos dos años. Se identificaron cuatro grupos de palabras clave relacionadas con la PND: síntomas, prevalencia y embarazo. Discusión y conclusión La escasa literatura sobre PND en México en comparación con otros países podría deberse a la limitada colaboración entre los institutos de salud. Se evidencia una necesidad urgente de realizar más investigaciones sobre PND en México que sean aplicables y útiles en la gestión de recursos en el sistema de salud.

Sex steroid receptors in the ovarian follicles of the lizard Sceloporus torquatus.

Estradiol and progesterone have been recognized as important mediators of reproductive events in the female mainly via binding to their receptors. This study aimed to characterize the immunolocalization of the estrogen receptor alfa (ERα), estrogen receptor beta (ERß) and progesterone receptor (PR) in the ovarian follicles of the lizard Sceloporus torquatus. The localization of steroid receptors has a spatio-temporal pattern that depends on the stage of follicular development. The immunostaining intensity of the three receptors was high in the pyriform cells and the cortex of the oocyte of previtellogenic follicles. During the vitellogenic phase, the granulosa and theca immunostaining was intense even with the modification of the follicular layer. In the preovulatory follicles, the receptors were found in yolk and additionally, ERα was also located in the theca. These observations suggest a role for sex steroids in regulating follicular development in lizards, like other vertebrates.

Sex steroids are correlated with environmental factors and body condition during the reproductive cycle in females of the lizard Sceloporus torquatus.

Reproduction is regulated by multiple factors that influence physiology and behavior to ensure the continuity of species. However, more work is needed to examine the complex relationships between environmental factors and endocrine transducers that modulate reproductive cycles, particularly in lizards. Here, we aimed to characterize the variation in plasma sex steroid levels in different stages of the reproductive cycle in the lizard Sceloporus torquatus and assess whether sex steroid levels were related to environmental factors (temperature, photoperiod, precipitation, and relative humidity) and body condition. Plasma concentrations of estradiol (E2) and progesterone (P4) from blood samples were quantified by enzyme-linked immunosorbent assay (ELISA) and radioimmunoanalysis (RIA), respectively. Our results indicate that sex steroid concentrations were positively related to follicular development but negatively related to temperature and precipitation. E2 increased as the follicles grew, and its concentrations were highest in the preovulatory phase. P4 showed a similar pattern and persisted during pregnancy. Changes in body condition were non-significant and mainly unrelated to the reproductive stage and plasma sex steroids. Our findings indicate that sex steroids change depending on the season and reproductive stage. We observed high concentrations of E2 and P4 in the late vitellogenic and preovulatory stages, probably because of their role in promoting vitellogenesis and ovulation. Additionally, we observed that follicular development is correlated with temperature and photoperiod. To better understand the mechanisms underlying reproduction, future studies of captive populations where environmental factors can be manipulated are needed.

A non-invasive method for semen collection and evaluation in small and median size lizards.

The aim of this study was to develop a non-invasive procedure to stimulate ejaculation in median and small lizards for semen collection. After semen collection, we applied a battery of tests to assess the motility (wave and progressive), viability (eosin-nigrosin stain), morphology (normal/abnormal), sperm concentration and ejaculate number, seminal volume and colour. We obtained this fluid from all males of the four species of sceloporine lizards (n = 30) and one species of Mexican horned lizards (n = 7). We found that semen from all males had a liquid-like consistency and a milky-white appearance. Ejaculate volume and sperm concentration varied among the males and the species studied. We also observed that although the mobility, viability and normal sperm morphology showed a wide variability, their average value in each species was high. We conclude that "genital papilla pressure" was an efficient and non-invasive semen obtaining method for small- and medium-sized lizards that does not imply damage to donors and could be used in other lizard species.