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Shi-Yu An, Zi-Fei Liu, El-Samahy M A, Ming-Tian Deng, Xiao-Xiao Gao, Ya-Xu Liang, Chen-Bo Shi, Zhi-Hai Lei, Feng Wang, and Guo-Min Zhang

Long ncRNAs 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 supressed testosterone (T) synthesis and 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.

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Anthony D Horlock, Thomas J R Ormsby, Martin J D Clift, José E P Santos, John J Bromfield, and I Martin Sheldon

Bovine granulosa cells are often exposed to energy stress, due to the energy demands of lactation, and exposed to lipopolysaccharide from postpartum bacterial infections. Granulosa cells mount innate immune responses to lipopolysaccharide, including the phosphorylation of mitogen-activated protein kinases and production of pro-inflammatory interleukins. Cellular energy depends on glycolysis, and energy stress activates intracellular AMPK (AMP-activated protein kinase), which in turn inhibits mTOR (mechanistic target of rapamycin). Here, we tested the hypothesis that manipulating glycolysis, AMPK or mTOR to mimic energy stress in bovine granulosa cells limits the inflammatory responses to lipopolysaccharide. We inhibited glycolysis, activated AMPK or inhibited mTOR in granulosa cells isolated from 4–8mm and from > 8.5 mm diameter ovarian follicles, and then challenged the cells with lipopolysaccharide and measured the production of interleukins IL-1α, IL-1β, and IL-8. We found that inhibiting glycolysis with 2-deoxy-d-glucose reduced lipopolysaccharide-stimulated IL-1α > 80%, IL-1β > 90%, and IL-8 > 65% in granulosa cells from 4–8 mm and from > 8.5 mm diameter ovarian follicles. Activating AMPK with AICAR also reduced lipopolysaccharide-stimulated IL-1α > 60%, IL-1β > 75%, and IL-8 > 20%, and shortened the duration of lipopolysaccharide-stimulated phosphorylation of the mitogen-activated protein kinase ERK1/2 and JNK. However, only the mTOR inhibitor Torin 1, and not rapamycin, reduced lipopolysaccharide-stimulated IL-1α and IL-1β. In conclusion, manipulating granulosa cell energy metabolism with a glycolysis inhibitor, an AMPK activator, or an mTOR inhibitor, limited inflammatory responses to lipopolysaccharide. Our findings imply that energy stress compromises ovarian follicle immune defences.

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Selena Park, Leann Walsh, and Karen M. Berkowitz

Ovarian aging in women correlates with the progressive loss of both the number and quality of oocytes. When these processes occur early or are accelerated, their clinical correlates are diminished ovarian reserve and/or premature ovarian insufficiency. Both these conditions have important consequences for the reproductive and general health of women, including infertility. Although there are many contributing factors, the molecular mechanisms underlying many of the processes associated with ovarian aging have not been fully elucidated. In this review, we highlight some of the most critical factors that impact oocyte quantity and quality with advancing age. We discuss chromosomal factors including cohesion deterioration and mis-segregation, errors in meiotic recombination, and decreased stringency of the spindle assembly checkpoint. DNA damage, telomere changes, reactive oxygen species and mitochondrial dysfunction as they relate to ovarian aging, and well-known gene mutations associated with primary ovarian insufficiency and diminished ovarian reserve are also discussed. Additionally, studies investigating recently acknowledged cytoplasmic factors associated with ovarian aging including protein metabolic dysregulation and microenvironmental alterations in the ovary are presented. We use both mouse and human studies to support the roles these factors play in physiologic and expedited ovarian aging, and we propose directions for future studies. A better understanding of the molecular basis of ovarian aging will ultimately lead to diagnostic and therapeutic advancements that would provide women with information to make earlier choices about their reproductive health.

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Carolina Marvaldi, Daniel Martin, Julia G Conte, María Florencia Gottardo, Matías L Pidre, Mercedes Imsen, Martin Irizarri, Sharron L Manuel, Francesca E Duncan, Víctor Romanowski, Adriana Seilicovich, and Gabriela Jaita

Humanin (HN) is a short peptide involved in many biological processes such as apoptosis, cell survival, inflammatory response, and reaction to stressors like oxidative stress, between others. In the ovary, a correct balance between pro- and anti-apoptotic factors is crucial for folliculogenesis. In the follicular atresia, survival or death of granulosa cells is a critical process. The goal of this study was to evaluate the action of HN on granulosa cell fate. To explore endogenous HN function in the ovary, we used a recombinant baculovirus (BV) encoding a short-hairpin RNA targeted to silence HN (shHN). HN downregulation modified ovarian histoarchitecture and increased apoptosis of granulosa cells. HN was also detected in a granulosa tumor cell line (KGN). Transduction of KGN cells with BV-shHN resulted in HN downregulation and increased apoptosis. On the other hand, treatment of KGN cells with exogenous HN increased cell viability and decreased apoptosis. In summary, these findings indicate that HN is a cytoprotective factor in granulosa cells of antral follicles, suggesting that this peptide would be involved in the regulation of folliculogenesis. Also, this peptide is a cytoprotective factor in KGN cells, and therefore, it could be involved in granulosa tumor cell behavior.

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Marc Kanbar, Maxime Vermeulen, and Christine Wyns

Organoids are 3D structures characterized by cellular spatial organizations and functions close to the native tissue they mimic. Attempts to create organoids originating from several tissues have now been reported, including the testis. Testicular organoids have the potential to improve our knowledge of the mechanisms that regulate testicular morphogenesis, physiology, and pathophysiology. They could especially prove as useful tools to understand the complex mechanisms involved in the regulation of the germ cell niche in infertility cases as they offer the possibility to control and modify the nature of cell types before self-assembly and thereby opening the perspective for developing innovative methods to restore fertility. To date, there are only few studies targeted at testicular organoids’ formation and even less describing the generation of organoids with both testis-specific structure and function. While researchers described interesting applications with regards to testicular tissue morphogenesis and drug toxicity, further research is needed before testicular organoids would eventually lead to the generation of fertilizing spermatozoa. This review will present the conventional systems used to induce in vitro maturation of testicular cells, describe the different approaches that have been used for the development of testicular organoids and discuss the potential applications they could have in the field of male reproductive biology.

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Takafumi Ushida, Tomomi Kotani, Yoshinori Moriyama, Charles C T Hindmarch, Tiziana Cotechini, Kenji Imai, Tomoko Nakano-Kobayashi, Hiroaki Kajiyama, and Charles H Graham

Women with a history of preeclampsia have an increased risk of subsequent cardiovascular and metabolic disease. While aberrant inflammation during pregnancy is associated with the development of preeclampsia, whether maternal inflammation increases the risk of disease later in life is unclear. Using a rat model we determined whether aberrant inflammation in pregnancy alters the levels of plasma proteins associated with cardiovascular and metabolic disease risk in the postpartum period. Pregnant rats were administered lipopolysaccharide (LPS) or saline on gestational days 13.5–16.5 to induce inflammation. Non-pregnant controls consisted of age-matched female rats subjected to similar administration of LPS or saline. Examination of the proteomic profile of plasma collected 16 weeks after delivery or from non-pregnant controls using liquid chromatography-tandem mass spectrometry revealed 100 differentially expressed proteins. Moreover, we identified 188 proteins in pregnant rats, of which 49 were differentially expressed in saline- vs LPS-treated dams. Of the 49 proteins regulated by LPS, 28 were pregnancy specific. PANTHER classification software, DAVID database and Ingenuity Pathways analysis revealed that the differentially expressed proteins in pregnant saline vs LPS-treated rats are associated with alterations in lipid and glucose metabolism and atherosclerosis, all of which may contribute to cardiovascular and metabolic disease risk. Results from proteomic and pathway analyses were validated by immunoassay of three serum proteins selected a priori and by assessment of serum metabolites. This discovery study demonstrates that aberrant inflammation during pregnancy results in long-lasting postpartum physiological alterations known to be associated with metabolic and cardiovascular disease.

Open access

Coleman H. Young, Bryce Snow, Stanely B. DeVore, Adithya Mohandass, Venkatesh V. Nemmara, Paul R. Thompson, Baskaran Thyagarajan, Amy Navratil, and Brian D. Cherrington

Peptidylarginine deiminases (PAD) enzymes were initially characterized in uteri, but since then little research has examined their function in this tissue. PADs post-translationally convert arginine residues in target proteins to citrulline and are highly expressed in ovine caruncle epithelia and an ovine uterine luminal epithelial (OLE) derived cell line. Progesterone (P4) not only maintains the uterine epithelia, but also regulates expression of histotroph genes critical during early pregnancy. Given this, we tested whether P4 stimulates PAD catalyzed histone citrullination to epigenetically regulate expression of the histotroph gene insulin like growth factor binding protein 1 (IGFBP1) in OLE cells. 100 nM P4 significantly increases IGFBP1 mRNA expression; however, this increase is attenuated by pre-treating OLE cells with 100 nM progesterone receptor antagonist RU486 or 2 µM of a pan-PAD inhibitor. P4 treatment of OLE cells also stimulates citrullination of histone H3 arginine residues 2, 8, and 17 leading to enrichment of the ovine IGFBP1 gene promoter. Since PAD2 nuclear translocation and catalytic activity require calcium, we next investigated whether P4 triggers calcium influx in OLE cells. OLE cells were pre-treated with 10 nM nicardipine, an L-type calcium channel blocker, followed by stimulation with P4. Using fura2-AM imaging, we found that P4 initiates a rapid calcium influx through L-type calcium channels in OLE cells. Furthermore, this influx is necessary for PAD2 nuclear translocation and resulting citrullination of histone H3 arginine residues 2, 8, and 17. Our work suggests that P4 stimulates rapid calcium influx through L-type calcium channels initiating PAD catalyzed histone citrullination and an increase in IGFBP1 expression.

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Tse-En Wang, Shiori Minabe, Fuko Matsuda, Sheng-Hsiang Li, Hiroko Tsukamura, Kei-Ichiro Maeda, Lee Smith, Laura O’Hara, Bart M Gadella, and Pei-Shiue Tsai

The epididymis is an androgen-responsive organ, whose structure and functions are modulated by the coordination between androgen and epididymal cues. Highly regulated molecular interaction within the epididymis is required to support viable sperm development necessary for subsequent fertilization. In the present study, we extended our earlier findings on a promising epididymal protein, quiescin sulfhydryl oxidase 2 (QSOX2), and demonstrated a positive correlation between testosterone and QSOX2 protein synthesis through the use of loss- and restore-of-function animal models. Moreover, based on transcriptomic analyses and 2D culture system, we determined that an additional polarized effect of glutamate is indispensable for the regulatory action of testosterone on QSOX2 synthesis. In conclusion, we propose noncanonical testosterone signaling supports epididymal QSOX2 protein synthesis, providing a novel perspective on the regulation of sperm maturation within the epididymis.

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Chunfang Xu, Weijie Zhao, Xixi Huang, Zhuxuan Jiang, Lu Liu, Liyuan Cui, Xinyi Li, Dajin Li, and Meirong Du

Decidualization is the functional transformation process of endometrium in response to ovarian steroids dedicated to support embryo development. Defective decidualization is closely associated with various pregnancy complications such as recurrent miscarriage (RM). Dual specificity MAPK phosphatases (MKPs) are a family of phosphatases specifically regulating mitogen-activated protein kinase (MAPK) signaling with dual specificity for threonine and tyrosine. Here, using RNA-seq,we found that dual specificity phosphatase 1 (DUSP1) expression was prominently elevated among the MKP family members in db-cAMP treated primary human endometrial stromal cells (ESCs). We verified that its induction by db-cAMP in ESCs was in a dose- and time-dependent manner and that primary human decidual stromal cells (DSCs) present higher expression of DUSP1 than ESCs. A protein kinase A (PKA) inhibitor H-89 abolished its induction in ESCs, but not ESI-09, an EPAC1/2 inhibitor. Knock-down of TORC2/3 but not CREB by siRNA in ESCs diminished its induction by db-cAMP. Furthermore, knock-down of DUSP1, as well as TORC2/3 by siRNA caused abnormal activation of JNK during db-cAMP induction in ESCs, accompanied by decreased IGFBP1 expression, an ESC decidualization indicator, which could be fully rescued by a JNK inhibitor SP600125. In addition, Western blot showed that DUSP1 expression was reduced in the DSCs of patients with RM, along with JNK overactivation and decreased IGFBP1 expression. In conclusion, our results demonstrated that TORC2/3-mediated DUSP1 upregulation in response to the cAMP/PKA signaling safeguards IGFBP1 expression via restraining JNK activity, indicating its involvement in ESC decidualization, and that aberrant expression of DUSP1 in DSCs might engage in the pathogenesis of RM.

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Gregory W. Kirschen, Abdelrahman AlAshqar, Mariko Miyashita-Ishiwata, Lauren Reschke, Malak El Sabeh, and Mostafa A. Borahay

Fibroids are benign tumors caused by proliferation of myometrial smooth muscle cells in the uterus that can lead to symptoms such as abdominal pain, constipation, urinary retention, and infertility. While traditionally thought of as a disease process intrinsic to the uterus, accumulating evidence suggests that fibroid growth may be linked with the systemic vasculature system, although cell-intrinsic factors are certainly of principal importance in their inception. Fibroids are associated with essential hypertension and preeclampsia, as well as atherosclerosis, for reasons that are becoming increasingly elucidated. Factors such as the renin-angiotensin-aldosterone system, estrogen, and endothelial dysfunction all likely play a role in fibroid pathogenesis. In this review, we lay out a framework for reconceptualizing fibroids as a systemic vascular disorder, and discuss how pharmaceutical agents and other interventions targeting the vasculature may aid in novel treatment of fibroids.