Melatonin and Vitamins as Protectors against the Reproductive Toxicity of Bisphenols: Which Is the Most Effective? A Systematic Review and Meta-Analysis.

Bisphenols such as bisphenol A (BPA), S (BPS), C (BPC), F (BPF), AF (BPAF), tetrabromobisphenol, nonylphenol, and octylphenol are plasticizers used worldwide to manufacture daily-use articles. Exposure to these compounds is related to many pathologies of public health importance, such as infertility. Using a protector compound against the reproductive toxicological effects of bisphenols is of scientific interest. Melatonin and vitamins have been tested, but the results are not conclusive. To this end, this systematic review and meta-analysis compared the response of reproductive variables to melatonin and vitamin administration as protectors against damage caused by bisphenols. We search for controlled studies of male rats exposed to bisphenols to induce alterations in reproduction, with at least one intervention group receiving melatonin or vitamins (B, C, or E). Also, molecular docking simulations were performed between the androgen (AR) and estrogen receptors (ER), melatonin, and vitamins. About 1234 records were initially found; finally, 13 studies were qualified for review and meta-analysis. Melatonin plus bisphenol improves sperm concentration and viability of sperm and increases testosterone serum levels compared with control groups; however, groups receiving vitamins plus bisphenols had lower sperm concentration, total testis weight, and testosterone serum levels than the control. In the docking analysis, vitamin E had the highest negative MolDock score, representing the best binding affinity with AR and ER, compared with other vitamins and melatonin in the docking. Our findings suggest that vitamins could act as an endocrine disruptor, and melatonin is most effective in protecting against the toxic effects of bisphenols.

Sperm morphophysiology in different sections of the rooster reproductive tract / Morfofisiología espermática en diferentes secciones del tracto reproductivo del gallo

It is important to know the morphological changes that occur in the spermatozoa of rooster during their passage through the reproductive tract, which help to understand what they acquire their fertilization capacity. The morphophysiological changes related to the capacitation and acrosomal reaction processes in the different segments of the rooster reproductive system were analyzed. Samples were obtained from various regions of the rooster reproductive tract and dorso-ventral massage to obtain ejaculates, 25 roosters were used Rhode Island Red with proven fertility, assessments were performed with chlortetracycline and Lectin WGA-FITC to determine the morphophysiological parameters. Sperm motility increases (p<0.05) during the passage of spermatozoa from the testis until they are ejaculated. The parameters of viability and morphology also show differences (p<0.05) in the different segments of the tract. Sperm morphometry shows a spermatic contraction (p<0.05) in the cranial and medial segments of the vas deferens. The acrosomal reaction capacity evaluated with chlortetracycline (CTC) or Wheat germ agglutinin (WGA), was evident increasing the parameters (p<0.05) with the use of the perivitelline layer in the spermatozoa of the reproductive tract and of the ejaculate. Spermatozoa of the reproductive tract of the rooster demonstrate acrosomal reaction capacity without requiring a previous sperm capacitation condition. On the other hand, they do not show parameters of incapacity, which implies that they cannot be stored in any segment of the reproductive tract.

Es importante conocer los cambios morfológicos que se producen en los espermatozoides del gallo durante su paso por el tracto reproductivo y que ayudan a comprender como adquieren su capacidad de fertilización. Se analizaron cambios morfofisiológicos relacionados con los procesos de capacitación y reacción acrosomal de los espermatozoides presentes en los diferentes segmentos del tracto reproductor del gallo. Se obtuvieron espermatozoides de diferentes regiones del tracto reproductor del gallo y de espermatozoides de eyaculado. Se usaron 25 gallos Rhode Island Red con fertilidad probada. Se realizaron evaluaciones básicas, con clortetraciclina (CTC) y lectina Wheat germ agglutinin conjugada con isotiosionato de fluoresceína (WGA-FITC) para determinar los parámetros morfofisiológicos. La motilidad del esperma aumenta (P<0,05) durante el paso de los espermatozoides desde el testículo hasta que son eyaculados. Los parámetros de viabilidad y morfología también muestran diferencias (P <0,05) en los diferentes segmentos del tracto. La morfometría mostró una contracción de los espermatozoides (P<0,05) en los segmentos craneal y medial del conducto deferente. La capacidad de reacción acrosomal evaluada con clortetraciclina CTC o WGAFITC, fue evidente al aumentar los parámetros (P<0,05) con el uso de membrana perivitelina en los espermatozoides del tracto reproductivo y del eyaculado. los espermatozoides del tracto reproductivo del gallo demuestran capacidad de reacción acrosomal sin requerir una condición previa de capacitación espermática. Por otro lado, no muestran parámetros de descapacitación espermática lo que implica que no pueden almacenar en ningún segmento del tracto reproductivo.

Surgical Extraction of Viable Hen ( Gallus gallus domesticus) Follicles for In Vitro Fertilization.

Assisted reproduction techniques in birds have been developed for zootechnical purposes and have been adapted for use in conservation of wild bird species. To develop a technique for obtaining follicles in live hens, 5 Rhode Island red hens ( Gallus gallus domesticus) were anesthetized, and abdominal ultrasound was performed to confirm the presence of ovarian follicles. A left celiotomy then was performed to obtain follicles in different stages of maturation for in vitro fertilization. The follicles were located by digital exploration, then extracted by isolating each follicle with the index finger of each hand, holding it by the stigma, and then applying slight traction towards the exterior of the coelomic cavity until the follicle separated from the ovary. In total, 18 of 30 (60%) follicles obtained were suitable for in vitro fertilization, but only 3 (16%) were fertilized successfully. All birds recovered from the procedure and remained in good condition postoperatively. Perfecting assisted reproduction technique holds potential benefits for determining sex of embryos by blastomeres sexing, supporting the conservation efforts of avian species, and benefiting research areas, such as genetic and biopharmaceutical research.