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Behzad Hajizadeh Maleki and Bakhtyar Tartibian

The existing evidence suggests that the human reproductive system may be potentially vulnerable to COVID-19 infection. However, little is known about the virus–host interaction of COVID-19 in sperm cells. We are the first to address the connection between changes in multiple seminal biomarkers and reproductive function in male patients recovering from COVID-19. In a prospective longitudinal cohort study, seminal ACE2 activity, markers of inflammation and oxidative stress, apoptotic variables, and semen quality parameters were evaluated at 10-day intervals for a maximum follow-up time of 60 days among male patients with laboratory-confirmed COVID-19 (n = 84) and healthy controls (CON; n = 105). At the baseline and the subsequent follow-ups, the COVID-19 group revealed significantly higher levels of seminal plasma ACE2 enzymatic activity, IL-1β, IL-6, IL-8, IL-10, TGF-β, TNF-α, IFN-α, IFN-γ, ROS, caspase-8, caspase-9, and caspase-3 activity as well as lower levels of SOD activity than those in the CON group (P  < 0.05). These perturbations tended to persist over time and were correlated with significant impairments in semen volume, progressive motility, sperm morphology, sperm concentration, and the number of spermatozoa. We provide the direct experimental evidence that the male reproductive system could be targeted and damaged by the COVID-19 infection. These findings go beyond our current understanding of the disease, suggesting that the reproductive function of the patients recovering from the disease should be precisely followed and evaluated to detect and avoid more serious reproductive problems in the future, as they may develop a transient state of male subfertility like those with oligoasthenoteratozoospermia.

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Sinan Ozkavukcu, Nilay Kuscu, Dileyra Adiguzel, Guldane Cengiz-Seval, and Ciler Celik-Ozenci

Nilotinib is a second-generation tyrosine kinase inhibitor (TKI) that is widely used to treat patients with Philadelphia chromosome-positive chronic myeloid leukaemia (CML). TKIs provided a significant improvement in terms of survival rates and disease-free period in CML; however, there is insufficient knowledge about their side effects, including reproductive toxicity. Since nearly half of the CML patients are in their reproductive age, and newly announced indications cover the treatment of the paediatric age groups, concerns arise about the effects of these drugs on the reproductive system, as there are no controlled preclinical studies. We investigated acute and long-term gonadotoxic and teratogenic effects of nilotinib, utilising a mouse model that simulates various clinical scenarios. We observed significant testicular damage in mice receiving nilotinib according to Johnsen’s score analysis. Alterations were observed in female mice’s number of follicles, as the primordial follicle numbers significantly decreased. Proliferating cell number in both genders’ gonads decreased and apoptosis rate increased significantly. The nilotinib-received female and male mice’s pregnancy rates were low compared to controls. A significant decrease in the thickness of the spongiotrophoblast and decidual layers of the placenta was detected in pregnancies consisting of male and/or female mice treated with nilotinib. The results of this study establish a critical point of view for clinical translation and indicate the importance of consulting patients for directing them to fertility preservation and contraception options for both genders before nilotinib treatment.

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Ana Filipa Ferreira, Maria Soares, Sandra Almeida Reis, João Ramalho-Santos, Ana Paula Sousa, and Teresa Almeida-Santos

Mitochondrial supplementation was proposed as a complementary treatment to assisted reproductive technologies to improve oocyte competence and support post-fertilization development. This strategy is based on the fact that poor-quality/aged oocytes contain lower and dysfunctional mitochondria. However, the efficacy and safety of mitochondrial supplementation are still controversial. Therefore, this review summarizes the clinical/biological outcomes of mitochondrial supplementation, aiming to improve oocyte competence or explore the safety of this technique, and was based on an online search using PubMed and Web of Science, until September 2019. The studies included reported outcomes related to the efficacy and safety of mitochondrial supplementation either in human or animal models (bovine, porcine and mouse). Extracted data were organized according to study objective, the mitochondrial source and the main outcomes: fertilization/pregnancy rates, embryo development and adverse outcomes. Clinical pregnancy was not improved in the only randomized controlled trial published, although an increase was demonstrated in other non-randomized studies. Fertilization rate and embryo development were not different from control groups in the majority of studies, although performed in different contexts and using diverse sources of mitochondria. The safety of mitochondria transfer is still a concern, however, the euploid rate and the absence of reported congenital malformation from the clinical studies are reassuring. In summary, mitochondrial supplementation does not seem to cause harm although the benefit of improving oocyte competence is still unclear due to the diversity of methodological approaches and low-quality of the data available. Analyzed data support the need to investigate further, in both pre-clinical and clinical contexts.

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Jacqueline M Wallace, John S Milne, and Raymond P Aitken

The competition for nutrients when pregnancy coincides with continuing growth in biologically immature adolescent girls increases their risk of preterm delivery and low birthweight and is partly replicated in the overnourished adolescent sheep paradigm. Although overfeeding to promote rapid maternal growth robustly leads to a reduction in average birthweight relative to slow-growing control-fed adolescents of equivalent age, the extent of prenatal compromise is variable. This retrospective analysis of a large cohort of identically managed pregnancies determined whether maternal anthropometry predicts the severity of fetal growth-restriction (FGR) in growing adolescents. Singleton pregnancies were established by embryo transfer in adolescents subsequently control-fed (n = 96) or overnourished. The latter pregnancies were classified as non-FGR (n = 116) or FGR (n = 96) if lamb birthweight was above or below the optimally fed control mean minus 2SD. A similar approach categorised placental growth-restriction (PlGR) and preterm delivery. Gestation length, placental mass and lamb birthweight were FGR < non-FGR < control (post hoc P < 0.01). Relative to the non-FGR group, overnourished dams with FGR were marginally leaner and lighter at conception (P = 0.023/P = 0.014) and had greater gestational weight gain (GWG) during the first-third of pregnancy (P < 0.001). GWG during this early period was also higher in PlGR compared with non-PlGR, and in very preterm vs term deliveries (P < 0.01). Likewise maternal leptin concentrations (fat accrual biomarker) were FGR > non-FGR by day 60, and changes in leptin throughout pregnancy predicted attenuated fetal cotyledon mass and birthweight (P = 0.01 to <0.001). The anthropometric antecedents of FGR in still-growing adolescent sheep originate in early pregnancy coincident with early placental development.

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Heather Flanagan, Chih-Jen Lin, Lisa L Campbell, Paddy Horner, Andrew W Horne, and Norah Spears

Ectopic pregnancy (EP) is defined as the implantation of an embryo outside of the uterus and is a leading cause of first trimester maternal mortality and morbidity. This article discusses a possible role for epithelial to mesenchymal transition in the pathogenesis of EP, given the notable similarity of protein expression between the two processes.

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Hossam El-Sheikh Ali, Kirsten E Scoggin, Rebecca Ruby, Alan Loynachan, Yatta Boakari, Claudia Fernandes, Pouya Dini, Carleigh Elizabeth Fedorka, Shavahn C Loux, Alejandro Esteller-Vico, and Barry A Ball

Cervical remodeling is a critical component in both term and preterm labor in eutherian mammals. However, the molecular mechanisms underlying cervical remodeling remain poorly understood in the mare. The current study compared the transcriptome of the equine cervix (cervical mucosa (CM) and stroma (CS)) during placentitis (placentitis group, n=5) and normal prepartum mares (prepartum group, n=3) to normal pregnant mares (control group, n=4). Transcriptome analysis identified differentially expressed genes (DEGs) during placentitis (5310 in CM and 907 in CS) and during the normal prepartum period (189 in CM and 78 in CS). Our study revealed that cervical remodeling during placentitis was dominated by inflammatory signaling as reflected by the overrepresented toll-like receptor signaling, interleukin signaling, T cell activation, and B cell activation pathways. These pathways were accompanied by upregulation of several proteases, including matrix metalloproteinases (MMP1, MMP2, and MMP9), cathepsins (CTSB, CTSC, and CTSD) and a disintegrin and metalloproteinase with thrombospondin type 1 motifs (ADAMTS1, ADAMTS4, and ADAMTS5), which are crucial for degradation of cervical collagens during remodeling. Cervical remodeling during placentitis was also associated with upregulation of water channel-related transcripts (AQP9 and RLN), angiogenesis-related transcripts (NOS3, ENG1, THBS1, and RAC2), and aggrecan (ACAN), a hydrophilic glucosaminoglycan, with subsequent cervical hydration. The normal prepartum cervix was associated with upregulation of ADAMTS1, ADAMTS4, NOS3 and THBS1, which might reflect an early stage of cervical remodeling taking place in preparation for labor. In conclusion, our findings revealed the possible key regulators and mechanisms underlying equine cervical remodeling during placentitis and the normal prepartum period.

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Natalie M Hohos, Emily M Elliott, Asma Giornazi, Elena Silva, John D Rice, and Malgorzata E Skaznik-Wikiel

High-fat diet (HFD) consumption in female rodents causes impaired estrous cyclicity, fewer pups per litter, and dysregulation of key ovulatory genes suggesting that HFD-induced subfertility may be due to ovulatory dysfunction. To test this hypothesis female mice were fed chow or HFD for 10 weeks at which point ovulation and ovarian gene expression of endothelin-2 (Edn2), a gene critical for ovulation, were assessed. After 10 weeks of HFD, both mice that remained lean and those that became obese had fewer ovulated oocytes than chow controls (P = 0.041, P = 0.0030, respectively). In chow controls, Edn2 was expressed as expected with basal levels during diestrus and proestrus, increased 11.6-fold during estrus, and decreased to basal levels during metestrus. In HFD mice, Edn2 was dysregulated across the entire estrous cycle as were other Edn2 system components (endothelin converting enzyme 1 (Ece-1), and the endothelin receptors (Ednra, Ednrb)). Interestingly, we found dysregulation of key ovarian steroidogenic genes after HFD. We also found that estradiol treatment in prepubertal mice increased Edn2 expression in the ovary (P = 0.030), suggesting that impaired steroidogenesis may be involved in the HFD-induced dysregulation of ovarian Edn2. In conclusion, HFD leads to ovulatory dysfunction regardless of the development of obesity, which appears to be mediated through dysregulation of ovarian Edn2 expression.

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Barry E Perlman, Audrey A Merriam, Alexander Lemenze, Qingshi Zhao, Salma Begum, Mohan Nair, Tracy Wu, Ronald J Wapner, Jan K Kitajewski, Carrie J Shawber, and Nataki C. Douglas

In the 1st trimester of human pregnancy, low oxygen tension or hypoxia, is essential for proper placentation and placenta function. Low oxygen levels and activation of signaling pathways have been implicated as critical mediators in the promotion of trophoblast differentiation, migration, and invasion with inappropriate changes in oxygen tension and aberrant Notch signaling both individually reported as causative to abnormal placentation. Despite crosstalk between hypoxia and Notch signaling in multuple cell types, the relationship between hypoxia and Notch in 1st trimester trophoblast function is not understood. To determine how a low oxygen environment impacts Notch signaling and cellular motility, we utilized the human 1st trimester trophoblast cell line, HTR-8/SVneo. Gene set enrichment and ontology analyses identified pathways involved in angiogenesis, Notch and cellular migration as upregulated in HTR-8/SVneo cells exposed to hypoxic conditions. DAPT, a -secretase inhibitor that inhibits Notch activation, was used to interrogate the crosstalk between Notch and hypoxia pathways in HTR-8/SVneo cells. We found that hypoxia requires Notch activation to mediate HTR-8/SVneo cell migration, but not invasion. To determine if our in vitro findings were associated with preeclampsia, we analyzed 2nd trimester chorionic villous sampling (CVS) samples and 3rd trimester placentas. We found a significant decrease in expression of migration and invasion genes in CVS from preeclamptic pregnancies, and significantly lower levels of JAG1 in placentas from pregnancies with early-onset preeclampsia with severe features. Our data support a role for Notch in mediating hypoxia-induced trophoblast migration, which may contribute to preeclampsia development.

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An Shi Yu, Zi-fei Liu, EI-Samahy M.a., Mingtian Deng, Gao Xiao Xiao, Liang Ya Xu, Chen-bo Shi, Zhihai Lei, Feng Wang, and Guomin Zhang

Long non-coding RNAs (lncRNAs) regulate a complex array of fundamental biological processes, while its molecular regulatory mechanism in Leydig cells (LCs) remains unclear. In the present study, we established the lncRNA LOC102176306/miR-1197-3p/peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A) regulatory network by bioinformatic prediction, and investigated its roles in goat LCs. We found that lncRNA LOC102176306 could efficiently bind to miR-1197-3p and regulate PPARGC1A expression in goat LCs. Downregulation of lncRNA LOC102176306 significantly repressed testosterone (T) synthesis and adenosine triphosphate (ATP) production, decreased the activities of antioxidant enzymes and mitochondrial complex I and complex III, caused the loss of mitochondrial membrane potential, and inhibited the proliferation of goat LCs by decreasing PPARGC1A expression, while these effects could be restored by miR-1197-3p inhibitor treatment. In addition, miR-1197-3p mimics treatment significantly alleviated the positive effects of lncRNA LOC102176306 overexpression on T and ATP production, antioxidant capacity and proliferation of goat LCs. Taken together, lncRNA LOC102176306 functioned as a sponge for miR-1197-3p to maintain PPARGC1A expression, thereby affecting the steroidogenesis, cell proliferation and oxidative stress of goat LCs. These findings extend our understanding of the molecular mechanisms of T synthesis, cell proliferation and oxidative stress of LCs.