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Open access

Yu-Fei Yang, Jia-Hao Wu, Run-Lan Lin, Shang-Jun Yin, Guo-Ying Qian, Wei Wang, and Yong-Doo Park

The Chinese soft-shelled turtle, Pelodiscus sinensis (Reptilia: Trionychidae), is a typical seasonal breeding species, and its spermatogenesis pattern is complex. In this study, the process of sperm cell development was studied using histology. The process of sperm cell development may be divided into six stages based on a combination of different cell types in the seminiferous epithelium. A close examination revealed two patterns of sperm cell development in the seminiferous tubules during the breeding season. The first is a normal sperm cell development pattern, in which the process of sperm cell development and maturation are completed in the seminiferous epithelium without round spermatozoa in the lumen. The second is rapid sperm cell development, in which the first batches of round spermatozoa fall off the seminiferous epithelium before they mature, thus beginning a second batch of sperm cell development. The round sperm cells are shed into the lumen and further mature in the seminiferous tubules and epididymis. This rapid sperm cell development process of the Chinese soft-shelled turtle is rare in other vertebrate species and may be an adaptation to cope with seasonal breeding. The results of this study provide insight into the theory of seasonal reproduction in reptiles.

Lay summary

The Chinese soft-shelled turtle is a typical seasonal breeding species, and the process of sperm cell development is complex. In this study, the process of sperm cell development is divided into six stages in Chinese soft-shelled turtles and revealed two patterns of sperm cell development in the testis during the breeding season. The first is a normal sperm cell development pattern, in which the process of sperm cell development and maturation are completed in the testis. The second is a rapid pattern, in which the round sperm cells fall off before they mature and further mature in the epididymis. This rapid sperm cell development process of the Chinese soft-shelled turtle is rare in other vertebrate species and may be an adaptation to cope with seasonal breeding. The results of this study provide insight into the theory of seasonal reproduction in reptiles.

Open access

Bonnie Grant, Anjali Pradeep, Suks Minhas, Waljit S Dhillo, Richard Quinton, and Channa N Jayasena

Lay summary

Anabolic steroids (also known as ‘steroids’) are banned drugs like testosterone, which make muscles bigger in men. These drugs are dangerous because they stop the testes from making natural testosterone and can cause heart attacks. Men stopping steroids have very low testosterone, which makes them feel weak, depressed, suicidal, infertile, and unable to have erections. We surveyed over 100 doctors to find out how they treat men giving up steroids. We report that doctors differ widely in the way they treat these men. Most doctors simply advise men to wait for the natural recovery of testosterone levels to happen. But 20% of doctors give men drugs to boost testosterone and make men feel better. Unfortunately, many patients had not recovered by the time of our survey. In summary, our survey highlights differences and limitations in the treatment of men giving up steroids. The use of steroids is increasing rapidly among young men, so we recommend further work to improve the treatment of men who are motivated to give up steroids.

Open access

E Scott Sills and Samuel H Wood

Ovarian platelet-rich plasma (PRP) is claimed to restore the fertility potential by improving reserve, an effect perhaps mediated epigenetically by platelet-discharged regulatory elements rather than gonadotropin-activated G-protein coupled receptors, as with stimulated in vitro fertilization (IVF). The finding that fresh activated platelet releasate includes factors able to promote developmental signaling networks necessary to enable cell pluripotency tends to support this theory. The mechanistic uncertainty of intraovarian PRP notwithstanding, at least two other major challenges confront this controversial intervention. The first challenge is to clarify how perimenopausal ovarian function is reset to levels consistent with ovulation. Perhaps a less obvious secondary problem is to confine this renewal such that any induced recalibration of cellular plasticity is kept within acceptable physiologic bounds. Thus, any ‘drive’ to ovarian rejuvenation must incorporate both accelerator and brake. Ovarian aging may be best viewed as a safeguard against pathologic overgrowth, where senescence operates as an evolved tumor-suppression response. While most ovary cells reach the close of their metabolic life span with low risk for hypertrophy, enhanced lysosomal activity and the proinflammatory ‘senescence-associated secretory phenotype’ usually offsets this advantage over time. But is recovery of ovarian fitness possible, even if only briefly prior to IVF? Alterations in gap junctions, bio-conductive features, and modulation of gene regulatory networks after PRP use in other tissues are discussed here alongside early data reported from reproductive medicine.

Open access

Menghe Liu, Katja Hummitzsch, Nicole A Bastian, Monica D Hartanti, Helen F Irving-Rodgers, Richard A Anderson, and Raymond J Rodgers

Polycystic ovary syndrome (PCOS) is an endocrine metabolic disorder that appears to have a genetic predisposition and a fetal origin. The fetal ovary has two major somatic cell types shown previously to be of different cellular origins and different morphologies and to differentially express 15 genes. In this study, we isolated the somatic gonadal ridge epithelial-like (GREL) cells (n  = 7) and ovarian fetal fibroblasts (n  = 6) by clonal expansion. Using qRT-PCR, we compared the gene expression levels of PCOS candidate genes with previous data on the expression levels in whole fetal ovaries across gestation. We also compared these levels with those in bovine adult ovarian cells including fibroblasts (n  = 4), granulosa cells (n  = 5) and surface epithelial cells (n  = 5). Adult cell types exhibited clear differences in the expression of most genes. In fetal ovarian cells, DENND1A and ERBB3 had significantly higher expression in GREL cells. HMGA2 and TGFB1I1 tended to have higher expression in fetal fibroblasts than GREL cells. The other 19 genes did not exhibit differences between GREL cells and fetal fibroblasts and FBN3, FSHB, LHCGR, FSHR and ZBTB16 were very lowly expressed in GREL cells and fibroblasts. The culture of fetal fibroblasts in EGF-containing medium resulted in lower expression of NEIL2 but higher expression of MAPRE1 compared to culture in the absence of EGF. Thus, the two fetal ovarian somatic cell types mostly lacked differential expression of PCOS candidate genes.

Lay summary

Polycystic ovary syndrome (PCOS) is one of the most common reproductive problems. The cause is not known so there are no specific treatments or prevention strategies. We know it can be linked to issues that occur in the womb and that some people may be more likely to get PCOS due to their genetic makeup. Our recent studies showed that many of the genes linked to PCOS were found to be switched on in the fetal ovary and are likely to be involved in the development of the fetal ovary. In order to improve our understanding of PCOS, we need to identify the type of cells in the fetal ovary where these genes are switched on. In this study, we examined the PCOS genes in two types of cells that mature as the fetal ovary develops and found very little difference between them but bigger differences to their mature adult counterparts.

Open access

Anna Lange-Consiglio, Emanuele Capra, Noemi Monferini, Simone Canesi, Giampaolo Bosi, Marina Cretich, Roberto Frigerio, Valentina Galbiati, Federica Bertuzzo, Francesco Cobalchini, Fausto Cremonesi, and Bianca Gasparrini

Extracellular vesicles (EVs) contained in seminal plasma, vehicle RNA, proteins, and other molecules able to influence the biological function of sperm. The aim of this study was to improve the fertilizing capacity of male gametes of low-fertility bulls using EVs isolated by ultracentrifugation from the seminal plasma of a bull of proven fertility. After a dose–response curve study, 10×106 sperm of low-fertility bulls were co-incubated for 1 h with 400×106 EVs/mL. In addition, it has been verified that the incorporation of EVs, which takes place in the sperm midpiece, is maintained for 5 h and even after cryopreservation. Subsequently, the spermatozoa of low-fertility bulls, with EVs incorporated, were used for the in vitro production of embryos. The rate of blastocyst at seventh day yield in vitro, with the use of sperm with EVs incorporated, increased by about twice the yield obtained with the same sperm in the absence of EVs: bulls having an average embryonic yield of 6.41 ± 1.48%, 10.32 ± 4.34%, and 10.92 ± 0.95% improved their yield to 21.21 ± 1.99%, 22.17 ± 6.09%, and 19.99 ± 5.78%, respectively (P < 0.05). These encouraging results suggest that it might be possible to keep breeding bulls with poor fertility. Further studies will be needed to evaluate the in vivo fertility of sperm treated with EVs and understand how the content of EVs is involve in the sperm–vesicle interaction and in the improved sperm performance.

Lay summary

Sperm can fertilize eggs after they mature as they move through the tube in the testes. As they move, the sperm communicate with the lining of the tubes, thanks to small sacs which are made by the tube itself. These sacs contain many molecules that may play a part in the mechanisms that help sperm fertilize eggs. In veterinary medicine, as with humans, there are fertile and less-fertile individuals. It is possible that the sacs of the semen from a bull which is known to be fertile are different to those from a bull with low fertility. For this reason, sacs from bulls with proven fertility were mixed with sperm from the less-fertile bulls to test in the laboratory how the sperm was able to fertilize eggs and produce embryos. The results show that, in the laboratory, the number of embryos produced is doubled. This suggests it would be possible to improve the fertility of people who are less fertile.

Open access

J M Roach, J C Arango-Sabogal, K C Smith, A K Foote, K L Verheyen, and A M de Mestre

Risk factors associated with equine reproductive efficiency have been identified along with those associated specifically with early pregnancy loss (EPL). In contrast, no studies have reported risk factors associated with abortion (loss between days 70 and 300 post-cover). Given the causes of abortion differ from those of EPL, likely too will the risk factors. A retrospective cohort study was carried out to identify risk factors associated with abortion in UK- and Irish-based Thoroughbreds, collecting data on 20 exposure variables over a 5-year period. A generalized linear mixed model was utilized to evaluate the associations between exposure variables and abortion, with clustering of observations accounted for at the mare and farm level. Variables with a likelihood ratio test (LRT) P value < 0.2 were entered into the model in a forward stepwise approach. Pregnancy outcome was available on 4439 pregnancies from 2510 mares. Having had two or more prior abortions (odds ratio (OR): 7.91, 95% CI: 2.86, 21.88), conceiving on the second or subsequent covered estrous cycle (OR: 1.84, 95% CI: 1.22, 2.78) and conceiving multiple conceptuses (OR: 1.68, 95% CI: 1.02, 2.76) were associated with an increased risk of abortion compared to null parous, first estrous cycle covers and singleton conceptions, respectively. Increasing paternal age (OR: 0.95, 95% CI: 0.90, 0.99) was associated with a decreasing risk of abortion. Mare and farm variance were not significant in the final model, LRT P = 0.43. These findings provide evidence-based data to inform Thoroughbred breeding management practices to help mitigate abortion risk.

Lay summary

This is the first study to identify the risk factors (characteristics which change the chance of an event) for abortion (miscarriage between days 70 and 300 of pregnancy) in the horse. Statistical models were used to account for the interactions between 20 different factors. The factor which increased the mare’s risk of having an abortion the most was when she had had two or more abortions prior to the pregnancy. Additionally, when the mare was initially pregnant with twins but one of those pregnancies was reduced, the remaining pregnancy was at an increased risk of aborting. Older mares were not at an increased risk of abortion like in humans; however, pregnancies fathered by older stallions were less likely to abort than those from younger stallions. The findings of this study can inform horse breeding practices to help reduce the chance of an abortion.

Open access

Kevin Marron and Conor Harrity

The purpose of this study was to determine if a comprehensive flow cytometry panel could be used to assess immunophenotype profiles in menstrual blood of patients experiencing reproductive failure and age-matched controls of proven fertility. Menstrual blood samples of 58 recurrent pregnancy loss and repeated implantation failure patients, along with 15 age-matched controls of proven fertility, were obtained within the first 24 h of the onset of menstruation to non-invasively assess the local immunophenotype. Using a comprehensive multi-parameter flow panel, the lymphocyte sub-populations were described and compared. In relation to well-established peripheral blood immunophenotyping values, distinct lymphocyte population differences were noted between the subgroups. The ratios of CD4+ and CD8+ T-cells were inverted in relation to peripheral blood, and uterine natural killler (NK) cells represented by CD56bright were distinctly visualised, emphasising the distinction between menstrual and peripheral blood. In relation to controls, there were marked increases in CD3+ve T-cells (P = 0.009), CD4:CD8 ratio (P = 0.004), CD19 B-cells (P = 0.026) and CD56dim NK cells (P = 0.002) in the reproductive failure cases. The study shows that flow cytometric evaluation could provide a rapid and objective analysis of lymphocyte subpopulations in many forms of tissue and fluid. The findings show significant variations in cellular composition of immune cells indicating a distinct compartment, with differences between cases and controls. Immunological assessment of the menstrual blood immunophenotype, in clinically appropriate patients, may provide insight into the aetiology of adverse reproductive outcome, without the risks and inconveniences associated with a more invasive endometrial biopsy.

Lay summary

Unexplained infertility is a difficult issue for patients and physicians, but despite diagnostic strides and innovative methods, there are no clear solutions. The involvement of an overactive or underactive immune system in selected cases is undeniable, and the endometrial lining is the most relevant area for investigation because this is where the embryo implants. Endometrial investigations, however, are highly invasive, involve medication and have to be done at the right time. The method described and evaluated here is an alternative assessment which avoids these difficulties and can be used in a clinical setting.

Open access

Lysia Demetriou, Christian M Becker, Beatriz Martínez-Burgo, Adriana L Invitti, Marina Kvaskoff, Razneen Shah, Emma Evans, Claire E Lunde, Emma Cox, Kurtis Garbutt, Krina T Zondervan, Elaine Fox, and Katy Vincent

Endometriosis is a chronic condition that affects ~10% of women globally. Its symptoms include chronic pelvic pain, heavy periods and tiredness/fatigue, which have been associated with poorer quality of life and mental health. We aim to explore the impact of the COVID-19 pandemic on pain and fatigue symptoms and their interactions with the impact on mental health in people with endometriosis. This global cross-sectional online survey study collected data from 4717 adults with self-reported surgical/radiological diagnosis of endometriosis between May and June 2020. The survey included questions on the current status and changes of endometriosis symptoms (pelvic pain, tiredness/fatigue, and bleeding patterns), mental health, pain catastrophising, and the impact of the COVID-19 pandemic on the respondents’ lives. Compared to 6 months earlier, Respondents reported a marked worsening of their endometriosis symptoms (endometriosis-associated pain (39.3%; 95% CI: 37.7, 40.5), tiredness/fatigue (49.9%; 95% CI: 48.4, 51.2) and bleeding patterns (39.6%; 95% CI: 38.2, 41)) and mental health (38.6%; 95% CI: 37.2, 39.9). Those with a pre-existing mental health diagnosis (38.8%) were more likely to report their symptoms worsening. Worsening of pain and tiredness/fatigue was significantly correlated with worsening of mental health (P < 0.001). The relationship between changes in mental health and (a) change in pain and (b) change in fatigue was found to be weakly mediated by pain catastrophising scores (pain: B = 0.071, lower limit of confidence interval (LLCI) = 0.060, upper limit of confidence interval (ULCI) = 0.082, tiredness/fatigue: B = 0.050, LLCI = 0.040, ULCI = 0.060). This study demonstrates that stressful experiences impact the physical and mental health of people with endometriosis. The findings highlight the need to consider psychological approaches in the holistic management of people with endometriosis.

Lay summary

Endometriosis is a chronic condition in which tissue similar to that of the lining of the womb grows outside it. It affects around 10% of women globally, and the symptoms often include persistent pelvic pain, heavy periods and tiredness/fatigue. These symptoms are associated with impaired mental health and life quality. This study used an online questionnaire to assess the experiences of people with endometriosis during the first months of the pandemic. Results from 4717 adults revealed that pelvic pain, tiredness/fatigue and bleeding worsened in more than 39% of the participants. Poor mental health was also exacerbated and associated with worsening in tiredness/fatigue. Further analysis revealed that this relationship could be partially explained by ‘pain catastrophising’, which measures how participants think about their pain. Our results suggest that stressful experiences like the pandemic negatively impact the already burdened mental health of people with endometriosis, who could benefit from psychological interventions.

Open access

Fabiana B Kohlrausch, Fang Wang, Danxia Luo, Rebecca Mahn, and David L Keefe

Lay summary

The placenta plays an essential role at the beginning of life, nourishing and supporting the fetus, but its life span is limited. In late pregnancy, the placenta develops signs of aging, including inflammation and impaired function, which may complicate pregnancy. Placentas also show another sign of aging – cells with extra or missing chromosomes. Chromosomally abnormal cells could gather in the placenta if they get stranded there and/or if the cells do not separate normally. Chromosome separation goes wrong in aging cells when the DNA sequences, which protect the ends of the chromosomes, erode. When chromosomes lose their protective caps, they fuse which leads to abnormal numbers of chromosomes. In this pilot study, for the first time, we found fusions between the caps in a human placenta when it reaches full term. More studies are needed to decide whether this has an influence on how the placenta works and outcomes of pregnancy.

Open access

Talita De Oliveira Farias, André Felipe Almeida Figueiredo, Natalia Teixeira Wnuk, Sônia Aparecida Talamoni, and Guilherme Mattos Jardim Costa

Yellowish myotis present a seasonal reproduction, influenced by rainfall distribution, in which the testis mass, germ cell composition, and brown adipose tissue (B.A.T.) mass change along the reproductive stages. In the present study, tissue xenografts were performed in immunodeficient mice to investigate spermatogenesis development in a stable endocrine milieu and the possible androgenic role of B.A.T. In this study, 41 adult male bats were captured in the Santuário do Caraça, Minas Gerais, Brazil. The gonads and B.A.T. were collected, weighed, and grafted under the mice's back skin. Mice biometric and hormonal data were evaluated after grafting, and the testis grafts and mice gonads were fixed for histological and immunohistochemical analyses. As a result, testis grafts from adult bats presented a continuous germ cell development in all reproductive stages, showing round spermatids in all testis tissues. Furthermore, testis fragments in the Rest stage presented elongating spermatids as the most advanced germ cell type in the seminiferous epithelium after 7 months of grafting. These data indicated that yellowish myotis spermatogenesis could be continued (presenting a constant spermatogonial differentiation) in a stable endocrine milieu, as found in mice. In addition, the best spermatogenic development was achieved when testis fragments were transplanted at their lowest activity (Rest stage). Regarding the B.A.T. grafts, the adipose tissue consumption by mice increased seminal vesicle mass and testosterone serum levels. This data proves that B.A.T. is related to testosterone synthesis, which may be critical in stimulating the differentiation of spermatogonia in yellowish myotis.

Lay summary

Bats are essential seed dispersers, pollinators, and agricultural pest regulators. Despite their ecological importance, bats face different threats due to environmental destruction and usually have few offspring per year. This study aimed to understand better how bats reproduce, but studying them in captivity is complicated and may not replicate what happens in the natural environment. To overcome this obstacle, we transplanted tissues from bats into mice which allowed in-depth research in lab conditions into bat reproduction. We looked at the tissues of adult bats after they had been transplanted into mice, and this allowed us to see which types of tissue played a critical role in reproduction.