Infertility is a global health problem involving about 15% of couples. Approximately half of the infertility cases are related to male factors. The oxidative stress, which refers to an imbalance in ...levels of reactive oxygen species (ROS) and antioxidants, is one of the main causes of infertility in men. A small amount of ROS is necessary for the physiological function of sperm including the capacitation, hyperactivation and acrosomal reaction. However, high levels of ROS can cause infertility through not only by lipid peroxidation or DNA damage but inactivation of enzymes and oxidation of proteins in spermatozoa. Oxidative stress (OS) is mainly caused by factors associated with lifestyle. Besides, immature spermatozoa, inflammatory factors, genetic mutations and altering levels of sex hormones are other main source of ROS. Since OS occurs due to the lack of antioxidants and its side effects in semen, lifestyle changes and antioxidant regimens can be helpful therapeutic approaches to overcome this problem. The present study aimed to describe physiological ROS production, roles of genetic and epigenetic factors on the OS and male infertility with various mechanisms such as lipid peroxidation, DNA damage, and disorder of male hormone profile, inflammation, and varicocele. Finally, the roles of oral antioxidants and herbs were explained in coping with OS in male infertility.
Equine semen is collected by conventional way, with a closed artificial vagina, where all the fractions are mixed. However, semen collection discontinuously, separating the different fractions of the ...ejaculate, each of these fractions have a greater or lesser amount of seminal plasma, being the sex accessory glands responsible for their production. Each stud has individual characteristics with respect to the maintenance of sperm cells during the cryopreservation, these characteristics may be related to production of seminal plasma as well as the various components making up. It is known that there is a deleterious effect played by components of seminal plasma mainly produced by the seminal vesicles, the sperm cells during the cryopreservation process, however, these factors are still unknown. Several hypotheses are suggested such as reducing the production of lipids and proteins and the types of ions present in each fraction of the ejaculate. Knowing this, the fractional harvest can be beneficial to sperm, so that the first fraction have no contact with seminal plasma produced by the seminal vesicles, allowing for better maintenance sperm during cryopreservation. Keywords: equine, fractionated collection, semen. As colheitas de semen em equinos sao realizadas de forma convencional, com vagina artificial fechada, em que todas as fracoes se misturam. No entanto, a colheita de semen de forma fracionada, separa as diferentes fracoes do ejaculado, cada uma dessas fracoes possuem uma maior ou menor quantidade de plasma seminal, sendo as glandulas sexuais acessorias responsaveis por sua producao. Cada garanhao possui caracteristicas individuais com relacao a manutencao das celulas espermaticas durante a criopreservacao, essas caracteristicas podem estar relacionadas a producao do plasma seminal, assim como dos varios componentes. Sabese que existe um efeito deleterio desempenhado pelos componentes do plasma seminal produzido principalmente pelas vesiculas seminais, aos espermatozoides durante o processo de criopreservacao, porem, esses fatores ainda sao desconhecidos. Varias hipoteses sao sugeridas, tais como, a reducao na producao de lipideos e os tipos de proteinas e ions presentes em cada uma das fracoes do ejaculado. Sabendo disso, a colheita fracionada pode trazer beneficios aos espermatozoides, de forma que as primeiras fracoes nao tenham contato com o plasma seminal produzido pelas vesiculas seminais, possibilitando uma melhor manutencao espermatica durante a criopreservacao. Palavras-chave: equino, colheita fracionada, semen. Las cosechas convencionales de semen equino, son realizadas con vagina artificial cerrada, donde todas las fracciones seminales quedan mescladas. No obstante, la colecta de semen de forma dividida o fraccionada, separa las diferentes "fracciones" del eyaculado. Fracciones que contiene una mayor o menor cantidad de plasma seminal, siendo las glandulas sexuales accesorias responsables por su produccion. Cada reproductor posee caracteristicas individuales con relacion al mantenimiento de las celulas espermaticas durante la criopreservacion, caracteristicas que pueden estar relacionadas a la produccion del plasma seminal, o a alguno de sus componentes. Es conocido la existencia de un efecto deletereo desempenado por los componentes del plasma seminal, producido principalmente por las vesiculas seminales a los espermatozoides durante el proceso de criopreservacion. Sin embargo, esos factores se desconocen. Varias hipotesis son sugeridas, tales como, reduccion en la produccion de lipidos y los tipos de proteinas e iones presentes en cada una de las fracciones del eyaculado. Sabiendo esto, la cosecha fraccionada puede traer beneficios a los espermatozoides, de forma que las primeras fracciones no tengan contacto con el plasma seminal producido por las vesiculas seminales, posibilitando una mejor manutencion espermatica durante la criopreservacion. Palabras claves: equino, cosecha fraccionada, semen.
Genetics of teratozoospermia: Back to the head Beurois, Julie; Cazin, Caroline; Kherraf, Zine-Eddine ...
Baillière's best practice and research in clinical endocrinology and metabolism/Baillière's best practice & research. Clinical endocrinology & metabolism,
December 2020, 2020-12-00, 2020-12, Letnik:
34, Številka:
6
Journal Article
Recenzirano
Odprti dostop
Spermatozoa are polarized cells with a head and a flagellum joined by the connecting piece. Head integrity is critical for normal sperm function, and head defects consistently lead to male ...infertility. Abnormalities of the sperm head are among the most severe and characteristic sperm defects. Patients presenting with a monomorphic head sperm defects such as globozoospermia or marcrozoospermia were analyzed permitting to identify several key genes for spermatogenesis such as AURKC and DPY19L2. The study of patients with other specific sperm head defects such as acephalic spermatozoa have also enabled the identification of new infertility genes such as SUN5. Here, we review the genetic causes leading to morphological defects of sperm head. Advances in the genetics of male infertility are necessary to improve the management of infertility and will pave the road towards future strategies of treatments, especially for patients with the most severe phenotype as sperm head defects.
The human sperm cell is very well suited for proteomic studies, as it is accessible, can be easily purified and is believed to be transcriptionally and translationally silent. The recent use of ...advanced proteomic approaches is clearly challenging the understanding of sperm biology. The aims of this review are to discuss the various human sperm proteomic studies, to create a compiled list of all the sperm proteins described to date and to re-assess the potential functional implications.
A search of the scientific literature available in the PubMed/Medline database at 31 December 2012 was conducted for studies on human sperm proteomics. The complete list of proteins obtained was carefully analysed using different bioinformatics tools, including Reactome, a knowledgebase of biological pathways.
A total of 30 studies were identified. The proteomics studies have resulted in the identification of 6198 different proteins, an important proportion of which (around 30%) are known to be expressed in the testis. The proteins were assigned to various functional pathways, including metabolism, apoptosis, cell cycle, meiosis and membrane trafficking, among others. Unexpectedly, the sperm cell also contains a range of proteins involved in RNA metabolism and translational regulation, as well as proteins usually located in organelles believed to be absent in sperm, such as cytoplasmatic ribosomes and peroxisomes. Additionally, some proteins whose levels seem to be altered in low-quality sperm might have clinical relevance.
The analysis of the most complete sperm proteome available to date indicates the presence of several cellular protein pathways previously ignored in the male gamete. Confirming the activity of each of these pathways and understanding their biological significance will certainly boost the knowledge of human sperm and male fertility and infertility in the next years.
The mammalian female reproductive tract interacts with sperm in various ways in order to facilitate sperm migration to the egg while impeding migrations of pathogens into the tract, to keep sperm ...alive during the time between mating and ovulation, and to select the fittest sperm for fertilization. The two main types of interactions are physical and molecular. Physical interactions include the swimming responses of sperm to the microarchitecture of walls, to fluid flows, and to fluid viscoelasticity. When sperm encounter walls, they have a strong tendency to remain swimming along them. Sperm will also orient their swimming into gentle fluid flows. The female tract seems to use these tendencies of sperm to guide them to the site of fertilization. When sperm hyperactivate, they are better able to penetrate highly viscoelastic media, such as the cumulus matrix surrounding eggs. Molecular interactions include communications of sperm surface molecules with receptors on the epithelial lining of the tract. There is evidence that specific sperm surface molecules are required to enable sperm to pass through the uterotubal junction into the oviduct. When sperm reach the oviduct, most bind to the oviductal epithelium. This interaction holds sperm in a storage reservoir until ovulation and serves to maintain the fertilization competence of stored sperm. When sperm are released from the reservoir, they detach from and re-attach to the epithelium repeatedly while ascending to the site of fertilization. We are only beginning to understand the communications that may pass between sperm and epithelium during these interactions.
Background Gestational trophoblastic disease (GTD) usually affects young women of childbearing age. After treatment for GTD, 86% of women wish to achieve pregnancy. On account of the impacts of GTD ...and treatments as well as patient anxiety, large numbers of couples turn to assisted reproductive technology (ART), especially in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). But few studies have investigated whether a history of GTD affects the outcomes of IVF/ICSI in secondary infertile patients and how it occurs. We investigate whether a history of GTD affects the IVF/ICSI outcomes and the live birth rates in women with secondary infertility. Methods This retrospective cohort study enrolled 176 women with secondary infertility who underwent IVF/ICSI treatment at the reproductive medical center of Nanjing Drum Tower Hospital from January 1, 2016, to December 31, 2020. Participants were divided into the GTD group (44 women with GTD history) and control group (132 women without GTD history matched from 8318 secondary infertile women). The control group and the study group were matched at a ratio of 3:1 according to patient age, infertility duration, number of cycles and body mass index (BMI). We assessed retrieved oocytes and high-grade embryos, biochemical pregnancy, miscarriage, ectopic pregnancy, gestational age at delivery, delivery mode and live birth rates. Result(s) We found a significantly reduced live-birth rate (34.1% vs 66.7%) associated with IVF/ICSI cycles in patients with a GTD history compared to those without a GTD history. The biochemical pregnancy and miscarriage rates of the GTD group were slightly higher than those of the control group. In addition, there was a difference in gestational age at delivery between the GTD and control groups (p < 0.001) but no differences in the mode of delivery (p = 0.267). Furthermore, the number of abandoned embryos in the GTD group was greater than that in the control group (p = 0.018), and the number of good-quality embryos was less than that in the control group (p = 0.019). The endometrial thickness was thinner (p < 0.001) in the GTD group. Immunohistochemistry (IHC) showed abnormal endometrial receptivity in the GTD group. Conclusion(s) The GTD history of patients undergoing IVF/ICSI cycles had an impact on the live-birth rate and gestational age at delivery, which might result from the thinner endometrium and abnormal endometrial receptivity before embryo transfer. Keywords: IVF/ICSI, GTD history, live-birth rate, gestational age at delivery, endometrial receptivity
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Spermatogenesis is one of the most complex and longest processes of sequential cell proliferation and differentiation in the body, taking more than a month from spermatogonial stem cells, through ...meiosis, to sperm formation. The whole process, therefore, has never been reproduced in vitro in mammals, nor in any other species with a very few exceptions in some particular types of fish. Here we show that neonatal mouse testes which contain only gonocytes or primitive spermatogonia as germ cells can produce spermatids and sperm in vitro with serum-free culture media. Spermatogenesis was maintained over 2 months in tissue fragments positioned at the gas-liquid interphase. The obtained spermatids and sperm resulted in healthy and reproductively competent offspring through microinsemination. In addition, neonatal testis tissues were cryopreserved and, after thawing, showed complete spermatogenesis in vitro. Our organ culture method could be applicable through further refinements to a variety of mammalian species, which will serve as a platform for future clinical application as well as mechanistic understanding of spermatogenesis.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Treatment of cancer with chemo- or radiotherapy causes reduction of sperm counts often to azoospermic levels that may persist for several years or be permanent. The time course of declines in sperm ...count can be predicted by the sensitivity of germ cells, with differentiating spermatogonia being most sensitive, and the known kinetics of recovery. Recovery from oligo- or azoospermia is more variable and depends on whether there is killing of stem cells and alteration of the somatic environment that normally supports differentiation of stem cells. Of the cytotoxic therapeutic agents, radiation and most alkylating drugs are the most potent at producing long-term azoospermia. Most of the newer biologic targeted therapies, except those used to target radioisotopes or toxins to cells, seem to have only modest effects, mostly on the endocrine aspects of the male reproductive system; however, their effects when used in combination with cytotoxic agents have not been well studied.
PDF
