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Sample records for leydig cells express

  1. Expression of cubilin in mouse testes and Leydig cells.

    PubMed

    Oh, Y S; Seo, J T; Ahn, H S; Gye, M C

    2016-04-01

    Cubilin (cubn) is a receptor for vitamins and various protein ligands. Cubn lacks a transmembrane domain but anchors to apical membranes by forming complexes with Amnionless or Megalin. In an effort to better understand the uptake of nutrients in testis, we analysed cubn expression in the developing mice testes. In testes, cubn mRNA increased from birth to adulthood. In the inter-stitium and isolated seminiferous tubules, neonatal increase in cubn mRNA until 14 days post-partum (pp) was followed by a marked increase at puberty (28 days pp). Cubn was found in the gonocytes, spermatogonia, spermatocytes and spermatids in the developing testes. In adult testes, strong Cubn immunoreactivity was found in the elongating spermatids, suggesting the role of Cubn in endocytosis during early spermiogenesis. In Sertoli cells and peritubular cells, Cubn immunoreactivity was weak throughout the testis development. In the inter-stitium, Cubn immunoreactivity was found in foetal Leydig cells, was weak to negligible in the stem cells and progenitor Leydig cells and was strong in immature and adult Leydig cells, demonstrating a positive association between Cubn and steroidogenic activity of Leydig cells. Collectively, these results suggest that Cubn may participate in the endocytotic uptake of nutrients in germ cells and somatic cells, supporting the spermatogenesis and steroidogenesis in mouse testes. PMID:26148765

  2. Expression of functional leptin receptors in rodent Leydig cells.

    PubMed

    Caprio, M; Isidori, A M; Carta, A R; Moretti, C; Dufau, M L; Fabbri, A

    1999-11-01

    Several studies indicate that the size of body fat stores and the circulating levels of the adipocyte-derived hormone leptin are able to influence the activity of the hypothalamic-pituitary-gonadal axis. The leptin-hypothalamic-pituitary-gonadal interactions have been mainly studied at the level of the central nervous system. In this study, we investigated the possibility that leptin may have direct effects on the rodent Leydig cell function. To probe this hypothesis, we first analyzed the expression of leptin receptors (OB-R) in rodent Leydig cells in culture. RT-PCR studies showed that rat Leydig cells express both the long (OB-Rb) and short isoform (OB-Ra) of leptin receptor, whereas MLTC-1 cells (a murine Leydig tumor cell line) express only the long isoform. Short-term (30-90 min) incubation of rat Leydig cells with increasing concentrations ofleptin (2-500 ng/ml) led to a significant and dose-dependent inhibition of human (h)CG-stimulated testosterone (T) production (approximately 60% reduction, IC50 = 20 ng/ml) but no change in basal androgen release. Also, leptin (150 ng/ml) amplified hCG-induced intracellular cAMP formation (1- to 2-fold) without modifying basal cAMP levels. Subsequent experiments showed that leptin inhibited 8Br-cAMP-stimulated T production, indicating that leptin's effect is exerted beyond cAMP. The inhibitory effect of leptin on hCG-induced T secretion was accompanied by a significant reduction of androstenedione and a concomitant rise of the precursor metabolites pregnenolone, progesterone, and 17-OH-progesterone, conceivable with a leptin-induced lesion of 17,20 lyase activity. Separate experiments performed with the MLTC-1 cells (not expressing cytochrome P450-17alpha) showed that leptin, though amplifying hCG-stimulated cAMP production, did not modify hCG-stimulated pregnenolone and progesterone release. These results further indicate that leptin action on steroidogenesis occurs downstream of progesterone synthesis. Northern Blot

  3. Aristaless Related Homeobox Gene, Arx, Is Implicated in Mouse Fetal Leydig Cell Differentiation Possibly through Expressing in the Progenitor Cells

    PubMed Central

    Miyabayashi, Kanako; Katoh-Fukui, Yuko; Ogawa, Hidesato; Baba, Takashi; Shima, Yuichi; Sugiyama, Noriyuki; Kitamura, Kunio; Morohashi, Ken-ichirou

    2013-01-01

    Development of the testis begins with the expression of the SRY gene in pre-Sertoli cells. Soon after, testis cords containing Sertoli and germ cells are formed and fetal Leydig cells subsequently develop in the interstitial space. Studies using knockout mice have indicated that multiple genes encoding growth factors and transcription factors are implicated in fetal Leydig cell differentiation. Previously, we demonstrated that the Arx gene is implicated in this process. However, how ARX regulates Leydig cell differentiation remained unknown. In this study, we examined Arx KO testes and revealed that fetal Leydig cell numbers largely decrease throughout the fetal life. Since our study shows that fetal Leydig cells rarely proliferate, this decrease in the KO testes is thought to be due to defects of fetal Leydig progenitor cells. In sexually indifferent fetal gonads of wild type, ARX was expressed in the coelomic epithelial cells and cells underneath the epithelium as well as cells at the gonad-mesonephros border, both of which have been described to contain progenitors of fetal Leydig cells. After testis differentiation, ARX was expressed in a large population of the interstitial cells but not in fetal Leydig cells, raising the possibility that ARX-positive cells contain fetal Leydig progenitor cells. When examining marker gene expression, we observed cells as if they were differentiating into fetal Leydig cells from the progenitor cells. Based on these results, we propose that ARX acts as a positive factor for differentiation of fetal Leydig cells through functioning at the progenitor stage. PMID:23840809

  4. Developmental and Endocrine Regulation of Kisspeptin Expression in Mouse Leydig Cells

    PubMed Central

    Adeshina, Ikeoluwa; Chen, Haolin; Zirkin, Barry R.; Hussain, Mehboob A.; Wondisford, Fredric; Wolfe, Andrew

    2015-01-01

    Kisspeptin, encoded by the Kiss1 gene, binds to a specific G protein-coupled receptor (kisspeptin1 receptor) to regulate the central reproductive axis. Kisspeptin has also been reported to be expressed in peripheral tissues, including the testes. However, factors regulating testicular kisspeptin and its role in reproduction are unknown. Our objective herein was to begin to address kisspeptin function in the testis. In particular, we sought to determine the level of kisspeptin in the testis in comparison with the brain and other tissues, how these levels change from the prepubertal period through sexual maturation, and the factors involved in kisspeptin regulation in the testis. Immunohistochemical analysis of testis sections using a validated kisspeptin antibody localized kisspeptin to the Leydig cells. Kisspeptin was not detected in germ cells or Sertoli cells within the seminiferous tubules at any developmental time period studied, from prepuberty to sexual maturation. A developmental time course of testicular kisspeptin revealed that its mRNA and protein levels increased during development, reaching robust levels at postnatal day 28, correlating with pubertal onset. In vitro studies of primary mouse Leydig cells, as well as in vivo studies, indicated clearly that LH is involved in regulating levels of Leydig cell kisspeptin. Interestingly, gonadectomy resulted in elevated LH but reduced serum kisspeptin levels, suggesting that testicular kisspeptin may be secreted. These data document kisspeptin expression in mouse Leydig cells, its secretion into peripheral serum, and its regulation by changes in reproductive neuroendocrine function. PMID:25635620

  5. Disruption of NHE8 expression impairs Leydig cell function in the testes.

    PubMed

    Xu, Hua; Chen, Huacong; Li, Jing; Zhao, Yang; Ghishan, Fayez K

    2015-02-15

    Multiple sodium/hydrogen exchanger (NHE) isoforms are expressed in the testes, and they play various roles in cell volume regulation, intracellular pH regulation, and fluid absorption. NHE8, the most recently characterized NHE family member, is detected in the Leydig cells in humans and mice in great abundance by immunohistochemistry in the current study. Male mice lacking NHE8 expression were infertile. Despite having intact male reproductive organs, male NHE8-/- mice have smaller testes and lacked spermatozoon in the seminiferous tubules and the epididymis. At the age of 39 wk, few spermogonia were seen in the testis in NHE8-/- mice. Although male NHE8-/- mice have normal serum levels of luteinizing hormone and follicle-stimulating hormone, serum testosterone level was significantly reduced. These mice have decreased expression of luteinizing hormone receptor in the testes. In NHE8 small-interfering RNA-transfected mouse Leydig cells (MLTC-1), silencing of NHE8 decreased the expression of luteinizing hormone receptor by ∼70%. Moreover, loss of NHE8 function in Leydig cells resulted in disorganized luteinizing hormone receptor membrane distribution. Therefore, male infertility in NHE8-/- mice is at least partially due to the disruption of luteinizing hormone receptor distribution and consequent low testosterone production, which leads to Sertoli cell dysfunction. Our work identified a novel role of NHE8 in male fertility through its effect on modifying luteinizing hormone receptor function. PMID:25472965

  6. Fetal Leydig Cells: Progenitor Cell Review Maintenance and Differentiation

    PubMed Central

    BARSOUM, IVRAYM B.; YAO, HUMPHREY H.-C.

    2012-01-01

    In most eutherian mammals, sexually dimorphic masculinization is established by androgen-producing fetal Leydig cells in the embryonic testis. Fetal Leydig cells, which lack expression of the testis-determining gene SRY, arise after the appearance of SRY-expressing Sertoli cells. Therefore, the appearance and differentiation of fetal Leydig cells are probably regulated by factors derived from Sertoli cells. Results from mouse genetic models have revealed that maintenance and differentiation of fetal Leydig cell population depends upon a balance between differentiation-promoting and differentiation-suppressing mechanisms. Although paracrine signaling via Sertoli cell–derived Hedgehog ligands is necessary and sufficient for fetal Leydig cell formation, cell-cell interaction via Notch signaling and intracellular transcription factors such as POD1 are implicated as suppressors of fetal Leydig cell differentiation. This review provides a model that summarizes the recent findings in fetal Leydig cell development. PMID:19875489

  7. Leydig cells: From stem cells to aging.

    PubMed

    Chen, Haolin; Ge, Ren-Shan; Zirkin, Barry R

    2009-07-10

    Leydig cells are the testosterone-producing cells of the testis. The adult Leydig cell population ultimately develops from undifferentiated mesenchymal-like stem cells present in the interstitial compartment of the neonatal testis. Four distinct stages of adult Leydig cell development have been identified and characterized: stem Leydig cells, progenitor Leydig cells, immature Leydig cells and adult Leydig cells. The stem Leydig cells are undifferentiated cells that are capable of indefinite self-renewal, differentiation, and replenishment of the Leydig cell niche. Progenitor Leydig cells are derived from the stem Leydig cells. These spindle-shaped cells are luteinizing hormone (LH) receptor positive, have high mitotic activity, and produce little testosterone but rather testosterone metabolites. The progenitor Leydig cells give rise to immature Leydig cells which are round, contain large amounts of smooth endoplasmic reticulum, and produce some testosterone but also very high levels of testosterone metabolites. A single division of these cells produces adult Leydig cells, which are terminally differentiated cells that produce high levels of testosterone. As men age, serum testosterone levels decline, and this is associated with alterations in body composition, energy level, muscle strength, physical, sexual and cognitive functions, and mood. In the Brown Norway rat, used extensively as a model for male reproductive aging, age-related reductions in serum testosterone result from significant decline in the ability of aged Leydig cells to produce testosterone in response to LH stimulation. This review describes Leydig cell development and aging. Additionally, the molecular mechanisms by which testosterone synthesis declines with aging are discussed. PMID:19481681

  8. Leydig cell tumours in childhood.

    PubMed

    Mengel, W; Knorr, D

    1983-01-01

    Two cases of Leydig cell tumours in childhood are presented. In one case, delayed diagnosis and operation led to pubertas praecox vera whereas in the other case normal growth and development occurred after early diagnosis and operation. PMID:6878724

  9. NGF induces adult stem Leydig cells to proliferate and differentiate during Leydig cell regeneration

    SciTech Connect

    Zhang, Lei; Wang, Huaxi; Yang, Yan; Liu, Hui; Zhang, Qihao; Xiang, Qi; Ge, Renshan; Su, Zhijian; Huang, Yadong

    2013-06-28

    Highlights: •Nerve growth factor has shown significant changes on mRNA levels during Adult Leydig cells regeneration. •We established the organ culture model of rat seminiferous tubules with ethane dimethyl sulphonate (EDS) treatment. •Nerve growth factor has shown proliferation and differentiation-promoting effects on Adult stem Leydig cells. •Nerve growth factor induces progenitor Leydig cells to proliferate and differentiate and immature Leydig cells to proliferate. -- Abstract: Nerve growth factor (NGF) has been reported to be involved in male reproductive physiology. However, few reports have described the activity of NGF during Leydig cell development. The objective of the present study was to examine the role of NGF during stem-Leydig-cell (SLC) regeneration. We investigated the effects of NGF on Leydig-cell (LC) regeneration by measuring mRNA levels in the adult rat testis after ethane dimethanesulfonate (EDS) treatment. Furthermore, we used the established organ culture model of rat seminiferous tubules to examine the regulation of NGF during SLC proliferation and differentiation using EdU staining, real-time PCR and western blotting. Progenitor Leydig cells (PLCs) and immature Leydig cells (ILCs) were also used to investigate the effects of NGF on LCs at different developmental stages. NGF mRNA levels changed significantly during Leydig-cell regeneration in vivo. In vitro, NGF significantly promoted the proliferation of stem Leydig cells and also induced steroidogenic enzyme gene expression and 3β-HSD protein expression. The data from PLCs and ILCs showed that NGF could increase Cyclin D1 and Hsd 17b3 mRNA levels in PLCs and Cyclin D1 mRNA levels in ILCs. These results indicate that NGF may play an important role during LC regeneration by regulating the proliferation and differentiation of LCs at different developmental stages, from SLCs to PLCs and from PLCs to ILCs. The discovery of this effect of NGF on Leydig cells will provide useful

  10. Time-Course Changes of Steroidogenic Gene Expression and Steroidogenesis of Rat Leydig Cells after Acute Immobilization Stress

    PubMed Central

    Lin, Han; Yuan, Kai-ming; Zhou, Hong-yu; Bu, Tiao; Su, Huina; Liu, Shiwen; Zhu, Qiqi; Wang, Yiyan; Hu, Yuanyuan; Shan, Yuanyuan; Lian, Qing-quan; Wu, Xiao-yun; Ge, Ren-shan

    2014-01-01

    Leydig cells secrete testosterone, which is essential for male fertility and reproductive health. Stress increases the secretion of glucocorticoid (corticosterone, CORT; in rats), which decreases circulating testosterone levels in part through a direct action by binding to the glucocorticoid receptors (NR3C1) in Leydig cells. The intratesticular CORT level is dependent on oxidative inactivation of glucocorticoid by 11β-hydroxysteroid dehydrogenase 1 (HSD11B1) in Leydig cells. In the present study, we investigated the time-course changes of steroidogenic gene expression levels after acute immobilization stress in rats. The plasma CORT levels were significantly increased 0.5, 1, 3 and 6 h after immobilization stress, while plasma testosterone levels were significantly reduced 3 and 6 h, after stress and luteinizing hormone (LH) did not change. Immobilization stress caused the down-regulation of Scarb1, Star and Cyp17a1 expression levels in the rat testis starting at the first hour of stress, ahead of the significant decreases of plasma testosterone levels. Other mRNA levels, including Cyp11a1, Hsd3b1 and Hsd17b3, began to decline after 3 h. Hsd11b1 and Nos2 mRNA levels did not change during the course of stress. Administration of glucocorticoid antagonist RU486 significantly restored plasma testosterone levels. In conclusion, Scarb1, Star and Cyp17a1 expression levels are more sensitive to acute stress, and acute immobilization stress causes the decline of the steroidogenic pathway via elevating the levels of glucocorticoid, which binds to NR3C1 in Leydig cells to inhibit steroidogenic gene expression. PMID:25405735

  11. Leydig cell aging and hypogonadism.

    PubMed

    Beattie, M C; Adekola, L; Papadopoulos, V; Chen, H; Zirkin, B R

    2015-08-01

    Leydig cell testosterone (T) production is reduced with age, resulting in reduced serum T levels (hypogonadism). A number of cellular changes have been identified in the steroidogenic pathway of aged Leydig cells that are associated with reduced T formation, including reductions in luteinizing hormone (LH)-stimulated cAMP production, the cholesterol transport proteins steroidogenic acute regulatory (STAR) protein and translocator protein (TSPO), and downstream steroidogenic enzymes of the mitochondria and smooth endoplasmic reticulum. Many of the changes in steroid formation that characterize aged Leydig cells can be elicited by the experimental alteration of the redox environment of young cells, suggesting that changes in the intracellular redox balance may cause reduced T production. Hypogonadism is estimated to affect about 5 million American men, including both aged and young. This condition has been linked to mood changes, worsening cognition, fatigue, depression, decreased lean body mass, reduced bone mineral density, increased visceral fat, metabolic syndrome, decreased libido, and sexual dysfunction. Exogenous T administration is now used widely to elevate serum T levels in hypogonadal men and thus to treat symptoms of hypogonadism. However, recent evidence suggests that men who take exogenous T may face increased risk of stroke, heart attack, and prostate tumorigenesis. Moreover, it is well established that administered T can have suppressive effects on LH, resulting in lower Leydig cell T production, reduced intratesticular T concentration, and reduced spermatogenesis. This makes exogenous T administration inappropriate for men who wish to father children. There are promising new approaches to increase serum T by directly stimulating Leydig cell T production rather than by exogenous T therapy, thus potentially avoiding some of its negative consequences. PMID:25700847

  12. Contribution of Leydig and Sertoli cells to testosterone production in mouse fetal testes.

    PubMed

    Shima, Yuichi; Miyabayashi, Kanako; Haraguchi, Shogo; Arakawa, Tatsuhiko; Otake, Hiroyuki; Baba, Takashi; Matsuzaki, Sawako; Shishido, Yurina; Akiyama, Haruhiko; Tachibana, Taro; Tsutsui, Kazuyoshi; Morohashi, Ken-ichirou

    2013-01-01

    Testosterone is a final product of androgenic hormone biosynthesis, and Leydig cells are known to be the primary source of androgens. In the mammalian testis, two distinct populations of Leydig cells, the fetal and the adult Leydig cells, develop sequentially, and these two cell types differ both morphologically and functionally. It is well known that the adult Leydig cells maintain male reproductive function by producing testosterone. However, it has been controversial whether fetal Leydig cells can produce testosterone, and the synthetic pathway of testosterone in the fetal testis is not fully understood. In the present study, we generated transgenic mice in which enhanced green fluorescence protein was expressed under the control of a fetal Leydig cell-specific enhancer of the Ad4BP/SF-1 (Nr5a1) gene. The transgene construct was prepared by mutating the LIM homeodomain transcription factor (LHX9)-binding sequence in the promoter, which abolished promoter activity in the undifferentiated testicular cells. These transgenic mice were used to collect highly pure fetal Leydig cells. Gene expression and steroidogenic enzyme activities in the fetal Leydig cells as well as in the fetal Sertoli cells and adult Leydig cells were analyzed. Our results revealed that the fetal Leydig cells synthesize only androstenedione because they lack expression of Hsd17b3, and fetal Sertoli cells convert androstenedione to testosterone, whereas adult Leydig cells synthesize testosterone by themselves. The current study demonstrated that both Leydig and Sertoli cells are required for testosterone synthesis in the mouse fetal testis. PMID:23125070

  13. IMMATURE RAT LEYDIG CELLS ARE INTRINSICALLY LESS SENSITIVE THAN ADULT LEYDIG CELLS TO ETHANE DIMETHANESULFONATE

    EPA Science Inventory

    Leydig cells from immature rat tests appear to be insensitive to doses of ethane-1,2-dimethanesulfonate (EDS) which eliminate Leydig cells from adult rat testes. e sought to determine whether this differential response to EDS is intrinsic to the Leydig cell or mediated by other i...

  14. Sirtuin 4 Regulates Lipopolysaccharide Mediated Leydig Cell Dysfunction.

    PubMed

    Ramatchandirin, Balamurugan; Sadasivam, Mohanraj; Kannan, Arun; Prahalathan, Chidambaram

    2016-04-01

    Bacterial lipopolysaccharide (LPS) is the most important contributing factor in pathogenesis of bacterial infection in male accessory glands; and it has shown to inhibit testicular steroidogenesis and induce apoptosis. The present study demonstrates that LPS causes mitochondrial dysfunction via suppression of sirtuin 4 (SIRT4); which in turn affects Leydig cell function by modulating steroidogenesis and apoptosis. LC-540 Leydig cells treated with LPS (10 µg/ml) showed impaired steroidogenesis and increased cellular apoptosis. The mRNA and protein expression of SIRT4 were decreased in LPS treated cells when compared to controls. The obtained data suggest that the c-Jun N-terminal kinase (JNK) activation suppresses SIRT4 expression in LPS treated Leydig cells. Furthermore, the overexpression of SIRT4 prevented LPS induced impaired steroidogenesis and cellular apoptosis by improving mitochondrial function. These findings provide valuable information that SIRT4 regulates LPS mediated Leydig cell dysfunction. PMID:26365714

  15. Hormone-Dependent Expression of a Steroidogenic Acute Regulatory Protein Natural Antisense Transcript in MA-10 Mouse Tumor Leydig Cells

    PubMed Central

    Castillo, Ana Fernanda; Fan, Jinjiang; Papadopoulos, Vassilios; Podestá, Ernesto J.

    2011-01-01

    Cholesterol transport is essential for many physiological processes, including steroidogenesis. In steroidogenic cells hormone-induced cholesterol transport is controlled by a protein complex that includes steroidogenic acute regulatory protein (StAR). Star is expressed as 3.5-, 2.8-, and 1.6-kb transcripts that differ only in their 3′-untranslated regions. Because these transcripts share the same promoter, mRNA stability may be involved in their differential regulation and expression. Recently, the identification of natural antisense transcripts (NATs) has added another level of regulation to eukaryotic gene expression. Here we identified a new NAT that is complementary to the spliced Star mRNA sequence. Using 5′ and 3′ RACE, strand-specific RT-PCR, and ribonuclease protection assays, we demonstrated that Star NAT is expressed in MA-10 Leydig cells and steroidogenic murine tissues. Furthermore, we established that human chorionic gonadotropin stimulates Star NAT expression via cAMP. Our results show that sense-antisense Star RNAs may be coordinately regulated since they are co-expressed in MA-10 cells. Overexpression of Star NAT had a differential effect on the expression of the different Star sense transcripts following cAMP stimulation. Meanwhile, the levels of StAR protein and progesterone production were downregulated in the presence of Star NAT. Our data identify antisense transcription as an additional mechanism involved in the regulation of steroid biosynthesis. PMID:21829656

  16. Genetics Home Reference: Leydig cell hypoplasia

    MedlinePlus

    ... triggers these cells to produce androgens. Androgens, including testosterone, are the hormones that control male sexual development ... or absent Leydig cells and impaired production of testosterone. A lack of testosterone interferes with the development ...

  17. A comprehensive survey of the laminins and collagens type IV expressed in mouse Leydig cells and their regulation by LH/hCG.

    PubMed

    Mazaud Guittot, Séverine; Vérot, Adélie; Odet, Fanny; Chauvin, Marie-Agnès; le Magueresse-Battistoni, Brigitte

    2008-04-01

    Extracellular matrix (ECM) proteins have been shown to alter Leydig cell steroidogenesis in vitro, substantiating the hypothesis that Leydig cell steroidogenic activity and matrix environment are interdependent events. However, the nature of the ECM components synthesized by Leydig cells and their regulation by LH/human chorionic gonadotropin (hCG) remain unknown. Here, we examine the occurrence of the 11 laminin subunits and the 6 alpha chains of collagen IV (COL4A1-6) by RT-PCR in Leydig cells cultured with or without LH/hCG. Leydig cells were a tumor Leydig cell line (mLTC-1) or 8-week-old mice Leydig cells. Based on PCR data, it is suggested that normal Leydig cells may synthesize a maximum of 11 laminin heterotrimers and the 6 alpha chains of collagen IV. They also may synthesize various proteases and inhibitors of the metzincin family. The mLTC-1 cells have a limited repertoire as compared with normal Leydig cells. Interestingly, none of the ten proteases and inhibitors monitored is under LH-hCG regulation whereas every protease and inhibitor of the serine protease family yet identified in Leydig cells is under gonadotropin regulation. In addition, a few laminin and collagen subunit genes are regulated by LH/hCG. These are laminins alpha3 and gamma3 (Lama3 and Lamc3), Col4a3, and Col4a6, which are negatively regulated by LH/hCG in both Leydig cell types, and Col4a4, which was downregulated in primary cultures but not in mLTC-1 cells. Collectively, the present study suggests that Leydig cells modulate in a selective fashion their matrix environment in response to their trophic hormone. This may alter the steroidogenic outcome of Leydig cells. PMID:18367508

  18. MEF2 Cooperates With Forskolin/cAMP and GATA4 to Regulate Star Gene Expression in Mouse MA-10 Leydig Cells.

    PubMed

    Daems, Caroline; Di-Luoffo, Mickaël; Paradis, Élise; Tremblay, Jacques J

    2015-07-01

    In Leydig cells, steroidogenic acute regulatory protein (STAR) participates in cholesterol shuttling from the outer to the inner mitochondrial membrane, the rate-limiting step in steroidogenesis. Steroid hormone biosynthesis and steroidogenic gene expression are regulated by LH, which activates various signaling pathways and transcription factors, including cAMP/Ca(2+)/CAMK (Ca(2+)/calmodulin-dependent kinase)-myocyte enhancer factor 2 (MEF2). The 4 MEF2 transcription factors are essential regulators of cell differentiation and organogenesis in numerous tissues. Recently, MEF2 was identified in Sertoli and Leydig cells of the testis. Here, we report that MEF2 regulates steroidogenesis in mouse MA-10 Leydig cells by acting on the Star gene. In MA-10 cells depleted of MEF2 using siRNAs (small interfering RNAs), STAR protein levels, Star mRNA levels, and promoter activity were significantly decreased. On its own, MEF2 did not activate the mouse Star promoter but was found to cooperate with forskolin/cAMP. By chromatin immunoprecipitation and DNA precipitation assays, we confirmed MEF2 binding to a consensus element located at -232 bp of the Star promoter. Mutation or deletion of the MEF2 element reduced but did not abrogate the MEF2/cAMP cooperation, indicating that MEF2 cooperates with other DNA-bound transcription factor(s). We identified GATA4 (GATA binding protein 4) as a partner for MEF2 in Leydig cells, because mutation of the GATA element abrogated the MEF2/cAMP cooperation on a reporter lacking a MEF2 element. MEF2 and GATA4 interact as revealed by coimmunoprecipitation, and MEF2 and GATA4 transcriptionally cooperate on the Star promoter. Altogether, our results define MEF2 as a novel regulator of steroidogenesis and Star transcription in Leydig cells and identify GATA4 as a key partner for MEF2-mediated action. PMID:25860031

  19. Regulation of NGFI-B/Nur77 gene expression in the rat ovary and in leydig tumor cells MA-10.

    PubMed

    Inaoka, Yoshihiko; Yazawa, Takashi; Uesaka, Miki; Mizutani, Tetsuya; Yamada, Kazuya; Miyamoto, Kaoru

    2008-05-01

    NR4A1, also called NGFI-B in the rat, Nur77 in the mouse and TR3 in humans, belongs to the orphan nuclear steroid hormone receptor superfamily and is one of the immediate-early genes. In the endocrine organs, including the gonads, NGFI-B/Nur77 gene expression is rapidly induced by pituitary hormones. NGFI-B/Nur77 expression was found to be rapidly reduced by an estrogenic endocrine disrupter, diethylstilbestrol (DES) in theca interna cells of immature rat ovaries. DES treatment also triggered a rapid decrease of serum luteinizing hormone (LH) levels, suggesting that DES acts on the hypothalamo-pituitary axis to suppress LH secretion from the pituitary. The transcriptional regulation of NGFI-B/Nur77 by LH/human chorionic gonadotropin (hCG) or 8-bromoadenosine 3'-5'-cyclic monophosphate (8 Br-cAMP) was examined in mouse Leydig tumor cells MA-10. Luciferase assays using NGFI-B/Nur77 promoter constructs and electric mobility shift assays (EMSA) showed that NGFI-B/Nur77 gene expression was mediated through three of the four activator protein-1 (AP-1)-like sites, namely the -233 AP-1, -213 AP-1 and -69 AP-1 sites adjacent to the transcription start site of the NGFI-B/Nur77 promoter. We also demonstrated here that both the Jun family and cAMP-responsive element binding (CREB) proteins bind to the -233 AP-1 site, whereas the main binding protein to the -213 AP-1 site was CREB, and Jun family protein to the -69 AP-1 site, respectively. The rapid induction of NGFI-B/Nur77 gene expression by LH/hCG in MA-10 cells appears to be mediated by both CREB and Jun family proteins through the cAMP-protein kinase A (PKA) pathway. PMID:18163434

  20. Ontogenesis of leptin receptor in rat Leydig cells.

    PubMed

    Caprio, Massimiliano; Fabbrini, Elisa; Ricci, Giulia; Basciani, Sabrina; Gnessi, Lucio; Arizzi, Mario; Carta, Anna R; De Martino, Massimo U; Isidori, Andrea M; Frajese, Giovanni V; Fabbri, Andrea

    2003-04-01

    There are still many controversies about the role of leptin in reproductive function and sexual development. We recently demonstrated that leptin receptors are expressed in rodent Leydig cells and that leptin has inhibitory effects on hCG-stimulated testosterone production by adult rat Leydig cells in culture. In this study, we evaluated the expression of leptin receptor (Ob-R) in rat testes from gestational to adult age in comparison with the pattern of expression of relaxin-like factor (RLF), a specific marker of Leydig cell differentiation status. Immunohistochemical analysis showed that, in prenatal life, Ob-R immunoreactivity was absent at early embryonic ages (E14.5) and appeared at a late embryonic age (E19.5); in postnatal life, immunoreactivity was evident only after sexual maturation (35-, 60-, and 90-days old), whereas it was absent in testes from sexually immature rats (7-, 14-, and 21-days old). Immunoreaction was always confined to Leydig cells and no signal of Ob-R was detected within the tubules. The pattern of expression of Ob-R during testicular development was similar with that of RLF immunoreactivity, which was present in mature fetal as well as adult-type Leydig cells. In contrast with the findings in the testis, in the hypothalamus, the immunohistochemical pattern of Ob-R was very similar between pre- and postpubertal life. Reverse transcription-polymerase chain reaction studies showed that Ob-R expression was present in embryonic, prepubertal, and adult rat testes; semiquantitative analysis showed that mRNA levels were much higher in late versus early embryonic testes, as well as in mature adults versus sexually immature testes, with a gradual increase from younger to older ages. Functional studies showed that, while leptin (150 ng/ml) significantly inhibited hCG-stimulated testosterone production in adult rat Leydig cells (46% reduction; P > 0.01), it did not modify prepubertal rat Leydig cells steroidogenic function in vitro. In conclusion

  1. MEF2 and NR2F2 cooperate to regulate Akr1c14 gene expression in mouse MA-10 Leydig cells.

    PubMed

    Di-Luoffo, M; Brousseau, C; Tremblay, J J

    2016-03-01

    Leydig cells are essential for male reproductive development and health throughout life. Production of androgens [testosterone, dihydrotestosterone (DHT)] as well as intermediate steroids [progesterone, dihydroprogesterone (DHP)] is tightly regulated. In the mouse, the 3α-hydroxysteroid dehydrogenase enzyme (3α-HSD, AKR1C14) catalyses the interconversion of DHP and DHT into less potent steroids. Despite its importance, nothing is currently known regarding the regulation of Akr1c14 expression in Leydig cells. Recently, the transcription factors MEF2 and NR2F2 were identified in the mouse testis including in Leydig cells where they were found to regulate expression of genes involved in steroidogenesis. Analyses of transcriptomic data from MEF2- or NR2F2-deficient MA-10 Leydig cells revealed a significant decrease in Akr1c14 mRNA levels. Using qPCR, we confirmed that Akr1c14 mRNA levels were decreased in MEF2- and in NR2F2-deficient conditions. Conversely, overexpression of MEF2A or/and NR2F2 in MA-10 Leydig cells led to an increase in endogenous Akr1c14 mRNA levels. Recruitment of MEF2 and NR2F2 to the Akr1c14 promoter was confirmed by ChIP while DNA precipitation assays revealed direct binding of MEF2 but not NR2F2 to this region. In functional promoter studies, NR2F2 was found to activate the Akr1c14 promoter while MEF2A on its own had no effect. Combination of both NR2F2 and MEF2A led to a cooperative activation of the Akr1c14 promoter and this required intact MEF2 and NR2F2 elements. Finally, co-immunoprecipitation experiments showed that MEF2 and NR2F2 are present in the same protein complex. In conclusion, our results identify a novel cooperation between MEF2 factors and NR2F2 in the expression of the Akr1c14 gene involved in the regulation of DHP/DHT levels. PMID:26748576

  2. Calcium-dependent Nr4a1 expression in mouse Leydig cells requires distinct AP1/CRE and MEF2 elements.

    PubMed

    Abdou, Houssein S; Robert, Nicholas M; Tremblay, Jacques J

    2016-04-01

    The nuclear receptor NR4A1 is expressed in steroidogenic Leydig cells where it plays pivotal roles by regulating the expression of several genes involved in steroidogenesis and male sex differentiation including Star, HSD3B2, and Insl3 Activation of the cAMP and Ca(2+) signaling pathways in response to LH stimulation leads to a rapid and robust activation of Nr4a1 gene expression that requires the Ca(2+)/CAMKI pathway. However, the downstream transcription factor(s) have yet to be characterized. To identify potential Ca(2+)/CaM effectors responsible for hormone-induced Nr4a1 expression, MA-10 Leydig cells were treated with forskolin to increase endogenous cAMP levels, dantrolene to inhibit endoplasmic reticulum Ca(2+) release, and W7 to inhibit CaM activity. We identified Ca(2+)-responsive elements located in the discrete regions of the Nr4a1 promoter, which contain binding sites for several transcription factors such as AP1, CREB, and MEF2. We found that one of the three AP1/CRE sites located at -255 bp is the most responsive to the Ca(2+) signaling pathway as are the two MEF2 binding sites at -315 and -285 bp. Furthermore, we found that the hormone-induced recruitment of phospho-CREB and of the co-activator p300 to the Nr4a1 promoter requires the Ca(2+) pathway. Lastly, siRNA-mediated knockdown of CREB impaired NR4A1 expression and steroidogenesis. Together, our data indicate that the Ca(2+) signaling pathway increases Nr4a1 expression in MA-10 Leydig cells, at least in part, by enhancing the recruitment of coactivator most likely through the MEF2, AP1, and CREB transcription factors thus demonstrating an important interplay between the Ca(2+) and cAMP pathways in regulating Nr4a1 expression. PMID:26647388

  3. Reprogramming of Sertoli cells to fetal-like Leydig cells by Wt1 ablation

    PubMed Central

    Zhang, Lianjun; Chen, Min; Wen, Qing; Li, Yaqiong; Wang, Yaqing; Wang, Yanbo; Qin, Yan; Cui, Xiuhong; Yang, Lin; Huff, Vicki; Gao, Fei

    2015-01-01

    Sertoli and Leydig cells, the two major somatic cell types in the testis, have different morphologies and functions. Both are essential for gonad development and spermatogenesis. However, whether these cells are derived from the same progenitor cells and the mechanism regulating the differentiation between these two cell types during gonad development remains unclear. A previous study showed that overactivation of Ctnnb1 (cadherin-associated protein, beta 1) in Sertoli cells resulted in Sertoli cell tumors. Surprisingly, in the present study, we found that simultaneous deletion of Wilms’ Tumor Gene 1 (Wt1) and overactivation of Ctnnb1 in Sertoli cells led to Leydig cell-like tumor development. Lineage tracing experiments revealed that the Leydig-like tumor cells were derived from Sertoli cells. Further studies confirmed that Wt1 is required for the maintenance of the Sertoli cell lineage and that deletion of Wt1 resulted in the reprogramming of Sertoli cells to Leydig cells. Consistent with this interpretation, overexpression of Wt1 in Leydig cells led to the up-regulation of Sertoli cell-specific gene expression and the down-regulation of steroidogenic gene expression. These results demonstrate that the distinction between Sertoli cells and Leydig cells is regulated by Wt1, implying that these two cell types most likely originate from the same progenitor cells. This study thus provides a novel concept for somatic cell fate determination in testis development that may also represent an etiology of male infertility in human patients. PMID:25775596

  4. Steroidogenesis in amlodipine treated purified Leydig cells

    SciTech Connect

    Latif, Rabia; Lodhi, Ghulam Mustafa; Hameed, Waqas; Aslam, Muhammad

    2012-01-01

    Drugs have been shown to adversely affect male fertility and recently anti-hypertensive drugs were added to the list. The anti-fertility effects of amlodipine, a calcium channel blocker, are well-illustrated in in vivo experiments but lack an in vitro proof. The present study was designed to experimentally elucidate the effects of amlodipine on Leydig cell steroidogenesis and intracellular calcium in vitro. Leydig cells of Sprague–Dawley rats were isolated and purified by Percoll. Cells were incubated for 3 h with/without amlodipine in the presence/absence of LH, dbcAMP, Pregnenolone and 25-Hydroxycholesterol. Cytosolic calcium was measured in purified Leydig cells by fluorometric technique. The results showed significantly reduced (P < 0.05) steroidogenesis and intracellular calcium in amlodipine exposed rats. The site of amlodipine induced steroidogenic inhibition seems to be prior to the formation of Pregnenolone at the level of StAR protein. -- Highlights: ► Inhibition of steroidogenesis in isolated and purified Leydig cells by amlodipine. ► Site of inhibition was before Pregnenolone formation, at the level of StAR protein. ► Inhibition of LH stimulated rise in cytosolic calcium by amlodipine.

  5. Establishment and evaluation of a stable steroidogenic goat Leydig cell line.

    PubMed

    Zhou, Jinhua; Dai, Rui; Lei, Lanjie; Lin, Pengfei; Lu, Xiaolong; Wang, Xiangguo; Tang, Keqiong; Wang, Aihua; Jin, Yaping

    2016-04-01

    Leydig cells play a key role in synthesizing androgen and regulating spermatogenesis. The dysfunction of Leydig cells may lead to various male diseases. Although primary Leydig cell cultures have been used, their finite lifespan hinders the assessment of long-term effects. In the present study, primary goat Leydig cells (GLCs) were immortalized via the transfection of a plasmid containing the human telomerase reverse transcriptase (hTERT) gene. The expressions of hTERT and telomerase activity were evaluated in transduced GLCs (hTERT-GLCs). These cells steadily expressed the hTERT gene and exhibited longer telomere lengths at passage 55 that were similar to those of HeLa cells. The hTERT-GLCs at passages 30 and 50 expressed genes that encoded key proteins, enzymes and receptors that are inherent to normal Leydig cells, for example, steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), 3β-hydroxysteroid dehydrogenase (3β-HSD) and LH-receptor (LH-R). Additionally, the immortalized goat Leydig cells secreted detectable quantities of testosterone in response to hCG stimulation. Furthermore, this cell line appeared to proliferate more quickly than the control cells, although no neoplastic transformation occurred in vitro. We concluded that the GLCs immortalized with hTERT retained their original characteristics and might provide a useful model for the study of Leydig cell function. PMID:26462462

  6. Cellular microenvironment dictates androgen production by murine fetal Leydig cells in primary culture.

    PubMed

    Carney, Colleen M; Muszynski, Jessica L; Strotman, Lindsay N; Lewis, Samantha R; O'Connell, Rachel L; Beebe, David J; Theberge, Ashleigh B; Jorgensen, Joan S

    2014-10-01

    Despite the fact that fetal Leydig cells are recognized as the primary source of androgens in male embryos, the mechanisms by which steroidogenesis occurs within the developing testis remain unclear. A genetic approach was used to visualize and isolate fetal Leydig cells from remaining cells within developing mouse testes. Cyp11a1-Cre mice were bred to mT/mG dual reporter mice to target membrane-tagged enhanced green fluorescent protein (GFP) within steroidogenic cells, whereas other cells expressed membrane-tagged tandem-dimer tomato red. Fetal Leydig cell identity was validated using double-labeled immunohistochemistry against GFP and the steroidogenic enzyme 3beta-HSD, and cells were successfully isolated as indicated by qPCR results from sorted cell populations. Because fetal Leydig cells must collaborate with neighboring cells to synthesize testosterone, we hypothesized that the fetal Leydig cell microenvironment defined their capacity for androgen production. Microfluidic culture devices were used to measure androstenedione and testosterone production of fetal Leydig cells that were cultured in cell-cell contact within a mixed population, were isolated but remained in medium contact via compartmentalized co-culture with other testicular cells, or were isolated and cultured alone. Results showed that fetal Leydig cells maintained their identity and steroidogenic activity for 3-5 days in primary culture. Microenvironment dictated proficiency of testosterone production. As expected, fetal Leydig cells produced androstenedione but not testosterone when cultured in isolation. More testosterone accumulated in medium from mixed cultures than from compartmentalized co-cultures initially; however, co-cultures maintained testosterone synthesis for a longer time. These data suggest that a combination of cell-cell contact and soluble factors constitute the ideal microenvironment for fetal Leydig cell activity in primary culture. PMID:25143354

  7. Cellular Microenvironment Dictates Androgen Production by Murine Fetal Leydig Cells in Primary Culture1

    PubMed Central

    Carney, Colleen M.; Muszynski, Jessica L.; Strotman, Lindsay N.; Lewis, Samantha R.; O'Connell, Rachel L.; Beebe, David J.; Theberge, Ashleigh B.; Jorgensen, Joan S.

    2014-01-01

    ABSTRACT Despite the fact that fetal Leydig cells are recognized as the primary source of androgens in male embryos, the mechanisms by which steroidogenesis occurs within the developing testis remain unclear. A genetic approach was used to visualize and isolate fetal Leydig cells from remaining cells within developing mouse testes. Cyp11a1-Cre mice were bred to mT/mG dual reporter mice to target membrane-tagged enhanced green fluorescent protein (GFP) within steroidogenic cells, whereas other cells expressed membrane-tagged tandem-dimer tomato red. Fetal Leydig cell identity was validated using double-labeled immunohistochemistry against GFP and the steroidogenic enzyme 3beta-HSD, and cells were successfully isolated as indicated by qPCR results from sorted cell populations. Because fetal Leydig cells must collaborate with neighboring cells to synthesize testosterone, we hypothesized that the fetal Leydig cell microenvironment defined their capacity for androgen production. Microfluidic culture devices were used to measure androstenedione and testosterone production of fetal Leydig cells that were cultured in cell-cell contact within a mixed population, were isolated but remained in medium contact via compartmentalized co-culture with other testicular cells, or were isolated and cultured alone. Results showed that fetal Leydig cells maintained their identity and steroidogenic activity for 3–5 days in primary culture. Microenvironment dictated proficiency of testosterone production. As expected, fetal Leydig cells produced androstenedione but not testosterone when cultured in isolation. More testosterone accumulated in medium from mixed cultures than from compartmentalized co-cultures initially; however, co-cultures maintained testosterone synthesis for a longer time. These data suggest that a combination of cell-cell contact and soluble factors constitute the ideal microenvironment for fetal Leydig cell activity in primary culture. PMID:25143354

  8. Malignant Leydig cell tumour of the testis.

    PubMed

    Powari, Manish; Kakkar, Nandita; Singh, S K; Rai, R S; Jogai, Sanjay

    2002-01-01

    A case of malignant Leydig cell tumour is presented. It is a rare primary malignant tumour of the testis and occurs exclusively in adults. The present case is of interest because it occurred at the young age of 25 years which is rare. Histologically it showed almost all features which suggest malignancy and also had metastases to the lungs and liver. The clinical details and pathology of this tumour are discussed. PMID:11803271

  9. Developmental exposures of male rats to soy isoflavones impact Leydig cell differentiation.

    PubMed

    Sherrill, Jessica D; Sparks, Morgan; Dennis, John; Mansour, Mahmoud; Kemppainen, Barbara W; Bartol, Frank F; Morrison, Edward E; Akingbemi, Benson T

    2010-09-01

    Testicular Leydig cells, which are the predominant source of the male sex steroid hormone testosterone, express estrogen receptors (ESRs) and are subject to regulation by estrogen. Following ingestion, the two major isoflavones in soybeans, genistin and daidzin, are hydrolyzed by gut microflora to form genistein and daidzein, which have the capacity to bind ESRs and affect gene expression. Thus, the increasing use of soy-based products as nondairy sources of protein has raised concerns about the potential of these products to cause reproductive toxicity. In the present study, perinatal exposure of male rats to isoflavones induced proliferative activity in Leydig cells. Isoflavones have the capacity to act directly as mitogens in Leydig cells, because genistein treatment induced Leydig cell division in vitro. Genistein action regulating Leydig cell division involved ESRs, acting in concert with signaling molecules in the transduction pathway mediated by protein kinase B (AKT) and mitogen-activated protein kinase (MAPK). Enhanced proliferative activity in the prepubertal period increased Leydig cell numbers, which alleviated deficits in androgen biosynthesis and/or augmented serum and testicular testosterone concentrations in adulthood. Together, these observations indicate that the perinatal exposures of male rats to isoflavones affected Leydig cell differentiation, and they imply that including soy products in the diets of neonates has potential implications for testis function. PMID:20554919

  10. Stress triggers mitochondrial biogenesis to preserve steroidogenesis in Leydig cells.

    PubMed

    Gak, Igor A; Radovic, Sava M; Dukic, Aleksandra R; Janjic, Marija M; Stojkov-Mimic, Natasa J; Kostic, Tatjana S; Andric, Silvana A

    2015-10-01

    Adaptability to stress is a fundamental prerequisite for survival. Mitochondria are a key component of the stress response in all cells. For steroid-hormones-producing cells, including also Leydig cells of testes, the mitochondria are a key control point for the steroid biosynthesis and regulation. However, the mitochondrial biogenesis in steroidogenic cells has never been explored. Here we show that increased mitochondrial biogenesis is the adaptive response of testosterone-producing Leydig cells from stressed rats. All markers of mitochondrial biogenesis together with transcription factors and related kinases are up-regulated in Leydig cells from rats exposed to repeated psychophysical stress. This is followed with increased mitochondrial mass. The expression of PGC1, master regulator of mitochondrial biogenesis and integrator of environmental signals, is stimulated by cAMP-PRKA, cGMP, and β-adrenergic receptors. Accordingly, stress-triggered mitochondrial biogenesis represents an adaptive mechanism and does not only correlate with but also is an essential for testosterone production, being both events depend on the same regulators. Here we propose that all events induced by acute stress, the most common stress in human society, provoke adaptive response of testosterone-producing Leydig cells and activate PGC1, a protein required to make new mitochondria but also protector against the oxidative damage. Given the importance of mitochondria for steroid hormones production and stress response, as well as the role of steroid hormones in stress response and metabolic syndrome, we anticipate our result to be a starting point for more investigations since stress is a constant factor in life and has become one of the most significant health problems in modern societies. PMID:26036344

  11. Glucocorticoid Receptor as a Potential Target to Decrease Aromatase Expression and Inhibit Leydig Tumor Growth.

    PubMed

    Panza, Salvatore; Malivindi, Rocco; Chemi, Francesca; Rago, Vittoria; Giordano, Cinzia; Barone, Ines; Bonofiglio, Daniela; Gelsomino, Luca; Giordano, Francesca; Andò, Sebastiano; Catalano, Stefania

    2016-05-01

    Leydig cell tumors are the most frequent interstitial neoplasms of the testis with increased incidence in recent years. They are hormonally active and are considered one of the steroid-secreting tumors. Although usually benign, the malignant phenotype responds poorly to conventional chemotherapy or radiation, highlighting the need to identify new therapeutic targets for treatment. Here, we identified a novel glucocorticoid-mediated mechanism that controls cell growth in Leydig cell tumors. We found that a synthetic glucocorticoid receptor agonist, dexamethasone, reduces cell proliferation in rat Leydig tumor cells by decreasing the expression and the enzymatic activity of the estrogen-producing enzyme aromatase. This inhibitory effect relies on the ability of activated glucocorticoid receptor to regulate the aromatase gene transcriptional activity through the recruitment of nuclear receptor corepressor protein and silencing mediator of retinoid and thyroid hormone receptors to a newly identified putative glucocorticoid responsive element within the aromatase promoter II. Our in vivo studies reveal a reduction of tumor growth, after dexamethasone treatment, in animal xenografts. Tumors from dexamethasone-treated mice exhibit a decrease in the expression of the proliferation marker Ki-67 and the aromatase enzyme. Our data demonstrate that activated glucocorticoid receptor, decreasing aromatase expression, induces Leydig tumor regression both in vitro and in vivo, suggesting that glucocorticoid receptor might be a potential target for the therapy of Leydig cell tumors. PMID:26968343

  12. Apoptosis Process in Mouse Leydig Cells during Postnatal Development

    NASA Astrophysics Data System (ADS)

    Salles Faria, Maria José; Simões, Zilá Paulino; Luz; Orive Lunardi, Laurelucia; Hartfelder, Klaus

    2003-02-01

    The development of Leydig cells in mammals has been widely described as a biphasic pattern with two temporally mature Leydig cell populations, fetal stage followed by the adult generation beginning at puberty. In the present study, mouse Leydig cells were examined for apoptosis during postnatal testis development using electron microscopy and in situ DNA fragmentation by terminal deoxynucleotidyl transferase staining (TdT). Both the morphological study and the DNA fragmentation analysis showed that cellular death by apoptosis did not occur in Leydig cells during the neonatal, prepubertal, puberty, and adult periods. From these results, we suggest that the remaining fetal Leydig cells in the neonatal testis are associated with the involution or degeneration processes. In contrast, in the prepubertal and puberty stages, fragmentation of apoptotic DNA was detected in germ cells present in some seminiferous tubules.

  13. EFFECTS OF ETHANE DIMETHANESULFONATE (EDS) ON ADULT AND IMMATURE RABBIT LEYDIG CELLS: COMPARISON WITH EDS-TREATED RAT LEYDIG CELLS

    EPA Science Inventory

    Ethane-dimethanesulfonate (EDS) has been shown to selectively kill Leydig cells and depress testosterone production in adult rats. ecent study has shown that immature rat leydig cells are less sensitive to EDS exposure. here is evidence that the rabbit metabolizes EDS to methane ...

  14. Effects of in Utero Exposure to Dicyclohexyl Phthalate on Rat Fetal Leydig Cells

    PubMed Central

    Li, Xiaoheng; Chen, Xiaomin; Hu, Guoxin; Li, Linxi; Su, Huina; Wang, Yiyan; Chen, Dongxin; Zhu, Qiqi; Li, Chao; Li, Junwei; Wang, Mingcang; Lian, Qingquan; Ge, Ren-Shan

    2016-01-01

    Dicyclohexyl phthalate (DCHP) is one of the phthalate plasticizers. The objective of the present study was to investigate the effects of DCHP on fetal Leydig cell distribution and function as well as testis development. Female pregnant Sprague Dawley dams orally received vehicle (corn oil, control) or DCHP (10, 100, and 500 mg/kg/day) from gestational day (GD) 12 to GD 21. At GD 21.5, testicular testosterone production, fetal Leydig cell number and distribution, testicular gene and protein expression levels were examined. DCHP administration produced a dose-dependent increase of the incidence of multinucleated gonocytes at ≥100 mg/kg. DCHP dose-dependently increased abnormal fetal Leydig cell aggregation and decreased fetal Leydig cell size, cytoplasmic size, and nuclear size at ≥10 mg/kg. DCHP reduced the expression levels of steroidogenesis-related genes (including Star, Hsd3b1, and Hsd17b3) and testis-descent related gene Insl3 as well as protein levels of 3β-hydroxysteroid dehydrogenase 1 (HSD3B1) and insulin-like 3 (INSL3) at ≥10 mg/kg. DCHP significantly inhibited testicular testosterone levels at ≥100 mg/kg. The results indicate that in utero exposure to DCHP affects the expression levels of fetal Leydig cell steroidogenic genes and results in the occurrence of multinucleated gonocytes and Leydig cell aggregation. PMID:26907321

  15. Mono-(2-ethylhexyl) Phthalate Directly Alters the Expression of Leydig Cell Genes and CYP17 Lyase Activity in Cultured Rat Fetal Testis

    PubMed Central

    Chauvigné, François; Plummer, Simon; Lesné, Laurianne; Cravedi, Jean-Pierre; Dejucq-Rainsford, Nathalie; Fostier, Alexis; Jégou, Bernard

    2011-01-01

    Exposure to phthalates in utero alters fetal rat testis gene expression and testosterone production, but much remains to be done to understand the mechanisms underlying the direct action of phthalate within the fetal testis. We aimed to investigate the direct mechanisms of action of mono-(2-ethylhexyl) phthalate (MEHP) on the rat fetal testis, focusing on Leydig cell steroidogenesis in particular. We used an in vitro system based on the culture for three days, with or without MEHP, of rat fetal testes obtained at 14.5 days post-coitum. Exposure to MEHP led to a dose-dependent decrease in testosterone production. Moreover, the production of 5 alpha-dihydrotestosterone (5α-DHT) (−68%) and androstenedione (−54%) was also inhibited by 10 µM MEHP, whereas 17 alpha-hydroxyprogesterone (17α-OHP) production was found to increase (+41%). Testosterone synthesis was rescued by the addition of androstenedione but not by any of the other precursors used. Thus, the hormone data suggested that steroidogenesis was blocked at the level of the 17,20 lyase activity of the P450c17 enzyme (CYP17), converting 17α-OHP to androstenedione. The subsequent gene expression and protein levels supported this hypothesis. In addition to Cyp17a1, microarray analysis showed that several other genes important for testes development were affected by MEHP. These genes included those encoding insulin-like factor 3 (INSL3), which is involved in controlling testicular descent, and Inha, which encodes the alpha subunit of inhibin B. These findings indicate that under in vitro conditions known to support normal differentiation of the fetal rat testis, the exposure to MEHP directly inhibits several important Leydig cell factors involved in testis function and that the Cyp17a1 gene is a specific target to MEHP explaining the MEHP-induced suppression of steroidogenesis observed. PMID:22087261

  16. Sertoli-Leydig cell tumor

    MedlinePlus

    ... the testes, release a male sex hormone called testosterone . These cells are also found in a woman's ... the levels of female and male hormones, including testosterone . An ultrasound or another imaging test will likely ...

  17. Estrogenic regulation of Leydig cell development in the rat

    SciTech Connect

    Myers, R.B.

    1989-01-01

    Initial studies demonstrated that treatment of male rats with estradiol for a period of four days resulted in a reduction in {sup 3}H-thymidine incorporation of isolated interstitial cells. Furthermore, {sup 3}H-thymidine incorporation in interstitial cells of 33 day old rats was inhibited by the addition of estradiol in vitro. Subsequent studies were performed in the ethylene dimethanesulphonate (EDS) treated rat. Leydig cells were rapidly destroyed after EDS administration as determined by hCG binding, steroid synthesis and morphological studies. A significant finding was the production of 5{alpha}-androstane-3{alpha},17{beta}-diol by regeneration Leydig cells of the EDS treated rat. In subsequent studies, rats received daily treatment with estradiol and/or hCG/LH after EDS treatment. Estradiol treatment had no effect on Leydig cell degeneration. Leydig cell regeneration, however, did not occur in the estradiol treated rat.

  18. The functional development of Leydig cells in a marsupial.

    PubMed

    Butler, Christopher M; Shaw, Geoff; Clark, Joan; Renfree, Marilyn B

    2008-01-01

    Leydig cells are the major source of androgen in the male mammal. We describe here for the first time the development of the Leydig cell in a macropodid marsupial, the tammar wallaby, Macropus eugenii. Leydig cells are first recognized morphologically 2 days after birth with the appearance of lipid droplets in the cytoplasm of certain interstitial cells. Lipid content closely matches the steroid content of the developing testis and marks the maturation of the steroid synthesis pathway in the tammar testis. Morphologically mature Leydig cells, marked by distinct mitochondria with tubular cristae and an extensive anastomosing network of smooth endoplasmic reticulum, are developed by day 10 after birth - the time of peak testosterone content in perinatal tammar testes. The volume percentage of each cell type in the testis does not change over time so the growth of each cellular component keeps pace with growth of the whole testis. There was no morphological or quantitative evidence of a change from one population of Leydig cells to another in the tammar testis as has been reported in several other species including the rat, mouse and human. Maturation of the testis is also marked by the development of tight junctions between the cell membranes of adjacent Sertoli cells. These appear around day 30 after birth and coincide with the onset of mitotic arrest in male germ cells. Overall, the development of the Leydig cell in the tammar wallaby follows a similar pattern to that seen in other mammals, although the start of Leydig cell differentiation is, like many other organ systems in marsupials, post natal, not fetal and there appears to be only a single population of Leydig cells. PMID:18069991

  19. The functional development of Leydig cells in a marsupial

    PubMed Central

    Butler, Christopher M; Shaw, Geoff; Clark, Joan; Renfree, Marilyn B

    2008-01-01

    Leydig cells are the major source of androgen in the male mammal. We describe here for the first time the development of the Leydig cell in a macropodid marsupial, the tammar wallaby, Macropus eugenii. Leydig cells are first recognized morphologically 2 days after birth with the appearance of lipid droplets in the cytoplasm of certain interstitial cells. Lipid content closely matches the steroid content of the developing testis and marks the maturation of the steroid synthesis pathway in the tammar testis. Morphologically mature Leydig cells, marked by distinct mitochondria with tubular cristae and an extensive anastomosing network of smooth endoplasmic reticulum, are developed by day 10 after birth – the time of peak testosterone content in perinatal tammar testes. The volume percentage of each cell type in the testis does not change over time so the growth of each cellular component keeps pace with growth of the whole testis. There was no morphological or quantitative evidence of a change from one population of Leydig cells to another in the tammar testis as has been reported in several other species including the rat, mouse and human. Maturation of the testis is also marked by the development of tight junctions between the cell membranes of adjacent Sertoli cells. These appear around day 30 after birth and coincide with the onset of mitotic arrest in male germ cells. Overall, the development of the Leydig cell in the tammar wallaby follows a similar pattern to that seen in other mammals, although the start of Leydig cell differentiation is, like many other organ systems in marsupials, post natal, not fetal and there appears to be only a single population of Leydig cells. PMID:18069991

  20. Effects of Neuroendocrine CB1 Activity on Adult Leydig Cells

    PubMed Central

    Cobellis, Gilda; Meccariello, Rosaria; Chianese, Rosanna; Chioccarelli, Teresa; Fasano, Silvia; Pierantoni, Riccardo

    2016-01-01

    Endocannabinoids control male reproduction acting at central and local level via cannabinoid receptors. The cannabinoid receptor CB1 has been characterized in the testis, in somatic and germ cells of mammalian and non-mammalian animal models, and its activity related to Leydig cell differentiation, steroidogenesis, spermiogenesis, sperm quality, and maturation. In this short review, we provide a summary of the insights concerning neuroendocrine CB1 activity in male reproduction focusing on adult Leydig cell ontogenesis and steroid biosynthesis. PMID:27375550

  1. Effects of Neuroendocrine CB1 Activity on Adult Leydig Cells.

    PubMed

    Cobellis, Gilda; Meccariello, Rosaria; Chianese, Rosanna; Chioccarelli, Teresa; Fasano, Silvia; Pierantoni, Riccardo

    2016-01-01

    Endocannabinoids control male reproduction acting at central and local level via cannabinoid receptors. The cannabinoid receptor CB1 has been characterized in the testis, in somatic and germ cells of mammalian and non-mammalian animal models, and its activity related to Leydig cell differentiation, steroidogenesis, spermiogenesis, sperm quality, and maturation. In this short review, we provide a summary of the insights concerning neuroendocrine CB1 activity in male reproduction focusing on adult Leydig cell ontogenesis and steroid biosynthesis. PMID:27375550

  2. 1,3-Dichloro-2-propanol inhibits progesterone production through the expression of steroidogenic enzymes and cAMP concentration in Leydig cells.

    PubMed

    Sun, Jianxia; Bai, Shun; Bai, Weibin; Zou, Feiyan; Zhang, Lei; Li, Guoqiang; Hu, Yunfeng; Li, Mingwei; Yan, Rian; Su, Zhijian; Huang, Yadong

    2014-07-01

    1,3-Dichloro-2-propanol (1,3-DCP) is a well-known food processing contaminant that has been shown to impede male reproductive function. However, its mechanism of action remains elusive. In this study, the effects of 1,3-DCP on progesterone production were investigated using the R2C Leydig cell model. 1,3-DCP significantly reduced cell viability from 7.48% to 97.4% at doses comprised between 0.5 and 6mM. Single cell gel/comet assays and atomic force microscopy assays showed that 1,3-DCP induced early phase cell apoptosis. In addition, 1,3-DCP significantly reduced progesterone production detected by radioimmunoassay (RIA). The results from quantitative polymerase chain reaction and western blotting demonstrated that the mRNA expression levels of steroidogenic acute regulatory protein (StAR), cytochrome P450 side-chain cleavage enzyme and 3β-hydroxysteroid dehydrogenase were significantly down-regulated in R2C cells. Particularly, the change rhythm of Star expression was highly consistent with progesterone production. Furthermore, the cyclic adenosine monophosphate (cAMP) and the mitochondrial membrane potential mediated by ROS, which are involved in regulating progesterone synthesis were also decreased in response to the 1,3-DCP treatment. Overall, the data presented here suggested that 1,3-DCP interferes with the male steroidogenic capacity mainly by down-regulating the level of cAMP and the key enzymes involved in the androgen synthesis pathway. PMID:24518350

  3. Selective GPER activation decreases proliferation and activates apoptosis in tumor Leydig cells.

    PubMed

    Chimento, A; Casaburi, I; Bartucci, M; Patrizii, M; Dattilo, R; Avena, P; Andò, S; Pezzi, V; Sirianni, R

    2013-01-01

    We have previously shown that estrogens binding to estrogen receptor (ER) α increase proliferation of Leydig tumor cells. Estrogens can also bind to G protein-coupled ER (GPER) and activation of this receptor can either increase or decrease cell proliferation of several tumor types. The aim of this study was to investigate GPER expression in R2C rat tumor Leydig cells, evaluate effects of its activation on Leydig tumor cell proliferation and define the molecular mechanisms triggered in response to its activation. R2C cells express GPER and its activation, using the specific ligand G-1, is associated with decreased cell proliferation and initiation of apoptosis. Apoptosis after G-1 treatment was asserted by appearance of DNA condensation and fragmentation, decrease in Bcl-2 and increase in Bax expression, cytochrome c release, caspase and poly (ADP-ribose) polymerase-1 (PARP-1) activation. These effects were dependent on GPER activation because after silencing of the gene, using a specific small interfering RNA, cyt c release, PARP-1 activation and decrease in cell proliferation were abrogated. These events required a rapid, however, sustained extracellular regulated kinase 1/2 activation. G-1 was able to decrease the growth of R2C xenograft tumors in CD1 nude mice while increasing the number of apoptotic cells. In addition, in vivo administration of G-1 to male CD1 mice did not cause any alteration in testicular morphology, while cisplatin, the cytotoxic drug currently used for the therapy of Leydig tumors, severely damaged testicular structure, an event associated with infertility in cisplatin-treated patients. These observations indicate that GPER targeting for the therapy of Leydig cell tumor may represent a good alternative to cisplatin to preserve fertility in Leydig tumor patients. PMID:23907461

  4. Selective GPER activation decreases proliferation and activates apoptosis in tumor Leydig cells

    PubMed Central

    Chimento, A; Casaburi, I; Bartucci, M; Patrizii, M; Dattilo, R; Avena, P; Andò, S; Pezzi, V; Sirianni, R

    2013-01-01

    We have previously shown that estrogens binding to estrogen receptor (ER) α increase proliferation of Leydig tumor cells. Estrogens can also bind to G protein-coupled ER (GPER) and activation of this receptor can either increase or decrease cell proliferation of several tumor types. The aim of this study was to investigate GPER expression in R2C rat tumor Leydig cells, evaluate effects of its activation on Leydig tumor cell proliferation and define the molecular mechanisms triggered in response to its activation. R2C cells express GPER and its activation, using the specific ligand G-1, is associated with decreased cell proliferation and initiation of apoptosis. Apoptosis after G-1 treatment was asserted by appearance of DNA condensation and fragmentation, decrease in Bcl-2 and increase in Bax expression, cytochrome c release, caspase and poly (ADP-ribose) polymerase-1 (PARP-1) activation. These effects were dependent on GPER activation because after silencing of the gene, using a specific small interfering RNA, cyt c release, PARP-1 activation and decrease in cell proliferation were abrogated. These events required a rapid, however, sustained extracellular regulated kinase 1/2 activation. G-1 was able to decrease the growth of R2C xenograft tumors in CD1 nude mice while increasing the number of apoptotic cells. In addition, in vivo administration of G-1 to male CD1 mice did not cause any alteration in testicular morphology, while cisplatin, the cytotoxic drug currently used for the therapy of Leydig tumors, severely damaged testicular structure, an event associated with infertility in cisplatin-treated patients. These observations indicate that GPER targeting for the therapy of Leydig cell tumor may represent a good alternative to cisplatin to preserve fertility in Leydig tumor patients. PMID:23907461

  5. Autocrine androgen action is essential for Leydig cell maturation and function, and protects against late-onset Leydig cell apoptosis in both mice and men

    PubMed Central

    O’Hara, Laura; McInnes, Kerry; Simitsidellis, Ioannis; Morgan, Stephanie; Atanassova, Nina; Slowikowska-Hilczer, Jolanta; Kula, Krzysztof; Szarras-Czapnik, Maria; Milne, Laura; Mitchell, Rod T.; Smith, Lee B.

    2015-01-01

    Leydig cell number and function decline as men age, and low testosterone is associated with all “Western” cardio-metabolic disorders. However, whether perturbed androgen action within the adult Leydig cell lineage predisposes individuals to this late-onset degeneration remains unknown. To address this, we generated a novel mouse model in which androgen receptor (AR) is ablated from ∼75% of adult Leydig stem cell/cell progenitors, from fetal life onward (Leydig cell AR knockout mice), permitting interrogation of the specific roles of autocrine Leydig cell AR signaling through comparison to adjacent AR-retaining Leydig cells, testes from littermate controls, and to human testes, including from patients with complete androgen insensitivity syndrome (CAIS). This revealed that autocrine AR signaling is dispensable for the attainment of final Leydig cell number but is essential for Leydig cell maturation and regulation of steroidogenic enzymes in adulthood. Furthermore, these studies reveal that autocrine AR signaling in Leydig cells protects against late-onset degeneration of the seminiferous epithelium in mice and inhibits Leydig cell apoptosis in both adult mice and patients with CAIS, possibly via opposing aberrant estrogen signaling. We conclude that autocrine androgen action within Leydig cells is essential for the lifelong support of spermatogenesis and the development and lifelong health of Leydig cells.—O’Hara, L., McInnes, K., Simitsidellis, I., Morgan, S., Atanassova, N., Slowikowska-Hilczer, J., Kula, K., Szarras-Czapnik, M., Milne, L., Mitchell, R. T., Smith, L. B. Autocrine androgen action is essential for Leydig cell maturation and function, and protects against late-onset Leydig cell apoptosis in both mice and men. PMID:25404712

  6. Genetic ablation of androgen receptor signaling in fetal Leydig cell lineage affects Leydig cell functions in adult testis.

    PubMed

    Kaftanovskaya, Elena M; Lopez, Carolina; Ferguson, Lydia; Myhr, Courtney; Agoulnik, Alexander I

    2015-06-01

    It is commonly accepted that androgen-producing fetal Leydig cells (FLC) are substituted by adult Leydig cells (ALC) during perinatal testis development. The mechanisms influencing this process are unclear. We used mice with a retinoid acid receptor 2 promoter-Cre recombinase transgene (Rarb-cre) expressed in embryonic FLC precursors, but not in postnatal testis, and a dual fluorescent Cre recombinase reporter to label FLC and ALC in vivo. All FLC in newborn testis had the recombinant, whereas the majority of LC in adult testis had the nonrecombinant reporter. Primary LC cultures from adult testis had either recombinant (20%) or nonrecombinant (80%) cells, demonstrating that the FLC survive in adult testis and their ontogeny is distinct from ALC. Conditional inactivation of androgen receptor (AR) allele using the Rarb-cre transgene resulted in a 50% increase of AR-negative LC in adult testis. The mutant males became infertile with age, with all LC in older testis showing signs of incomplete differentiation, such as a large number of big lipid droplets, an increase of finger-like protrusions, and a misexpression of steroidogenic or FLC- and ALC-specific genes. We propose that the antiandrogenic exposure during early development may similarly result in an increase of FLC in adult testis, leading to abnormal LC differentiation. PMID:25713029

  7. Modulatory effects of leptin on leydig cell function of normal and hyperleptinemic rats.

    PubMed

    Giovambattista, Andrés; Suescun, María O; Nessralla, Claudio C D L; França, Luiz R; Spinedi, Eduardo; Calandra, Ricardo S

    2003-11-01

    Neonatal L-monosodium glutamate (MSG) administration in rats induces several neuroendocrine and metabolic disruptions. Leptin, the adipocyte product, modulates several neuroendocrine systems including the hypothalamic-pituitary-gonadal (HPG) axis in mammals. The aim of the present study was to determine whether MSG-induced chronic hyperleptinemia could play any relevant role in the hypogonadism developed by male rats when examined in adulthood. We found that 120-day-old MSG male rats displayed significant hyperleptinemia, hypogonadism, and undisturbed basic testis structure and spermatogenesis. In vitro studies in purified Leydig cells from normal (CTR) and MSG-damaged rats revealed that basal and human chorionic gonadotropin (hCG)-stimulated 17-hydroxy-progesterone (17-HO-P(4)), Delta(4)-androstenedione (Delta(4)A) and testosterone (T) secretions were significantly lower in MSG than in CTR cells. Exposure to murine leptin (Mleptin, 10(-8)M) significantly inhibited hCG-elicited T secretion by CTR cells after 180 min incubation. While Mleptin significantly inhibited hCG-stimulated Delta(4)A output and the Delta(4)A:17-OH-P(4) ratio of secretion, conversely, it failed to modify the ratio T:Delta(4)A release by CTR Leydig cells. Interestingly, the effects of Mleptin found on CTR Leydig cells were absent in MSG Leydig cells. Finally, endogenous hyperleptinemia was associated with a significant decrease in Leydig cell expression of Ob-Rb mRNA in MSG rats. In summary, this study demonstrates that: (1) Mleptin inhibited testicular steroidogenesis in CTR rats; (2) MSG-treated rats showed lower in vitro 17-OH-P(4), Delta(4)A and T production under basal and post-hCG stimulation conditions; (3) purified Leydig cells from MSG-treated rats displayed resistance to the inhibitory action of Mleptin on T release, and (4) endogenous leptin exerts a modulatory effect on Leydig cell Ob-Rb mRNA expression. The inhibitory effect of leptin on testicular function is thus abrogated in MSG

  8. GATA4 Is a Key Regulator of Steroidogenesis and Glycolysis in Mouse Leydig Cells

    PubMed Central

    Schrade, Anja; Kyrönlahti, Antti; Akinrinade, Oyediran; Pihlajoki, Marjut; Häkkinen, Merja; Fischer, Simon; Alastalo, Tero-Pekka; Velagapudi, Vidya; Toppari, Jorma; Wilson, David B.

    2015-01-01

    Transcription factor GATA4 is expressed in somatic cells of the mammalian testis. Gene targeting studies in mice have shown that GATA4 is essential for proper differentiation and function of Sertoli cells. The role of GATA4 in Leydig cell development, however, remains controversial, because targeted mutagenesis experiments in mice have not shown a consistent phenotype, possibly due to context-dependent effects or compensatory responses. We therefore undertook a reductionist approach to study the function of GATA4 in Leydig cells. Using microarray analysis and quantitative RT-PCR, we identified a set of genes that are down-regulated or up-regulated after small interfering RNA (siRNA)-mediated silencing of Gata4 in the murine Leydig tumor cell line mLTC-1. These same genes were dysregulated when primary cultures of Gata4flox/flox adult Leydig cells were subjected to adenovirus-mediated cre-lox recombination in vitro. Among the down-regulated genes were enzymes of the androgen biosynthetic pathway (Cyp11a1, Hsd3b1, Cyp17a1, and Srd5a). Silencing of Gata4 expression in mLTC-1 cells was accompanied by reduced production of sex steroid precursors, as documented by mass spectrometric analysis. Comprehensive metabolomic analysis of GATA4-deficient mLTC-1 cells showed alteration of other metabolic pathways, notably glycolysis. GATA4-depleted mLTC-1 cells had reduced expression of glycolytic genes (Hk1, Gpi1, Pfkp, and Pgam1), lower intracellular levels of ATP, and increased extracellular levels of glucose. Our findings suggest that GATA4 plays a pivotal role in Leydig cell function and provide novel insights into metabolic regulation in this cell type. PMID:25668067

  9. Annexin A5 regulates Leydig cell testosterone production via ERK1/2 pathway.

    PubMed

    He, Ze; Sun, Qin; Liang, Yuan-Jiao; Chen, Li; Ge, Yi-Feng; Yun, Shi-Feng; Yao, Bing

    2016-01-01

    This study was to investigate the effect of annexin A5 on testosterone secretion from primary rat Leydig cells and the underlying mechanisms. Isolated rat Leydig cells were treated with annexin A5. Testosterone production was detected by chemiluminescence assay. The protein and mRNA of Steroidogenic acute regulatory (StAR), P450scc, 3β-hydroxysteroid dehydrogenase (3β-HSD), 17β-hydroxysteroid dehydrogenase (17β-HSD), and 17α-hydroxylase were examined by Western blotting and semi-quantitative RT-PCR, respectively. Annexin A5 significantly stimulated testosterone secretion from rat Leydig cells in dose- and time-dependent manners and increased mRNA and protein expression of StAR, P450scc, 3β-HSD, and 17β-HSD but not 17α-hydroxylase. Annexin A5 knockdown by siRNA significantly decreased the level of testosterone and protein expression of P450scc, 3β-HSD, and 17β-HSD. The significant activation of ERK1/2 signaling was observed at 5, 10, and 30 min after annexin A5 treatment. After the pretreatment of Leydig cells with ERK inhibitor PD98059 (50 μmol l-1 ) for 20 min, the effects of annexin A5 on promoting testosterone secretion and increasing the expression of P450scc, 3β-HSD, and 17β-HSD were completely abrogated (P < 0.05). Thus, ERK1/2 signaling is involved in the roles of annexin A5 in mediating testosterone production and the expression of P450scc, 3β-HSD, and 17β-HSD in Leydig cells. PMID:26289400

  10. Sertoli Cells Maintain Leydig Cell Number and Peritubular Myoid Cell Activity in the Adult Mouse Testis

    PubMed Central

    Monteiro, Ana; Milne, Laura; Cruickshanks, Lyndsey; Jeffrey, Nathan; Guillou, Florian; Freeman, Tom C.; Mitchell, Rod T.; Smith, Lee B.

    2014-01-01

    The Sertoli cells are critical regulators of testis differentiation and development. In the adult, however, their known function is restricted largely to maintenance of spermatogenesis. To determine whether the Sertoli cells regulate other aspects of adult testis biology we have used a novel transgenic mouse model in which Amh-Cre induces expression of the receptor for Diphtheria toxin (iDTR) specifically within Sertoli cells. This causes controlled, cell-specific and acute ablation of the Sertoli cell population in the adult animal following Diphtheria toxin injection. Results show that Sertoli cell ablation leads to rapid loss of all germ cell populations. In addition, adult Leydig cell numbers decline by 75% with the remaining cells concentrated around the rete and in the sub-capsular region. In the absence of Sertoli cells, peritubular myoid cell activity is reduced but the cells retain an ability to exclude immune cells from the seminiferous tubules. These data demonstrate that, in addition to support of spermatogenesis, Sertoli cells are required in the adult testis both for retention of the normal adult Leydig cell population and for support of normal peritubular myoid cell function. This has implications for our understanding of male reproductive disorders and wider androgen-related conditions affecting male health. PMID:25144714

  11. The prenylflavonoid phytoestrogens 8-prenylnaringenin and isoxanthohumol diferentially suppress steroidogenesis in rat Leydig cells in ontogenesis.

    PubMed

    Izzo, Gaia; Söder, Olle; Svechnikov, Konstantin

    2011-08-01

    8-Prenylnaringenin and isoxanthohumol are prenylflavonoids found in the hop plant, Humulus lupulus (Cannabaceae), which is traditionally used to add bitterness and flavor to beer. Flavonoids have previously been reported to exert endocrine disrupting actions. Therefore, we investigated the effects of 8-prenylnaringenin and isoxanthohumol on steroidogenesis activated by human chorionic gonadotropin (hCG) in primary cultures of rat Leydig cells at different stages of their development. The present study is the first to demonstrate that the prenylflavonoids 8-prenylnaringenin and isoxanthohumol exert complex maturation-dependent effects on Leydig cell steroidogenesis. Those compounds inhibited hCG-stimulated androgen production by Leydig cells at all stages of their development, a process that was associated with the reduced ability of the cells to produce cAMP. However, these same compounds up-regulated hCG-activated StAR expression in progenitor (PLC) and immature (ILC) but not adult types of Leydig cells (ALC). Further, 8-prenylnaringenin and isoxanthohumol were not able to suppress androgen production activated by an exogenous analog of cAMP, (Bu)2 cAMP, in ALC and ILC but synergistically stimulated steroidogenesis in PLC. Our data suggest that 8-prenylnaringenin and isoxanthohumol affect cAMP-dependent cellular processes up-stream transport of cholesterol into mitochondria. PMID:21061451

  12. Antiviral responses of human Leydig cells to mumps virus infection or poly I:C stimulation

    PubMed Central

    Le Tortorec, A.; Denis, H.; Satie, A-P.; Patard, J-J.; Ruffault, A.; Jégou, B.; Dejucq-Rainsford, N.

    2008-01-01

    BACKGROUND The immuno-privileged status of the testis is essential to the maintenance of its functions, and innate immunity is likely to play a key role in limiting harmful viral infections, as demonstrated in the rat. In men mumps virus infects Leydig cells and has deleterious effects on testosterone production and spermatogenesis. The aim of this study was to test whether mumps virus infection of isolated human Leydig cells was associated with an inhibition of their innate antiviral defences. METHODS Leydig cell production of mRNA and protein for interferons (IFNs) and of three antiviral proteins—2′5′ oligoadenylate synthetase (2′5′OAS), double-stranded RNA-activated protein kinase (PKR) and MxA—was investigated, in the absence or presence of mumps virus or viral stimuli including poly I:C, a mimetic of RNA viruses replication product. RESULTS Stimulated or not, human Leydig cells appeared unable to produce routinely detectable IFNs α, β and γ. Although the level of PKR remained unchanged after stimulation, the expression of 2′5′OAS and MxA was enhanced following either mumps virus or poly I:C exposure (P < 0.05 versus control). CONCLUSIONS Overall, our results demonstrate that mumps virus replication in human Leydig cells is not associated with a specific inhibition of IFNs or 2′5′OAS, MxA and PKR production and that these cells display relatively weak endogenous antiviral abilities, as opposed to their rat counterparts. PMID:18567898

  13. H4 histamine receptors inhibit steroidogenesis and proliferation in Leydig cells.

    PubMed

    Abiuso, Adriana María Belén; Berensztein, Esperanza; Pagotto, Romina María; Pereyra, Elba Nora; Medina, Vanina; Martinel Lamas, Diego José; Besio Moreno, Marcos; Pignataro, Omar Pedro; Mondillo, Carolina

    2014-12-01

    The histamine H4 receptor (HRH4), discovered only 13 years ago, is considered a promising drug target for allergy, inflammation, autoimmune disorders and cancer, as reflected by a steadily growing number of scientific publications and patent applications. Although the presence of HRH4 has been evidenced in the testis, its specific localization or its role has not been established. Herein, we sought to identify the possible involvement of HRH4 in the regulation of Leydig cell function. We first evaluated its expression in MA-10 Leydig tumor cells and then assessed the effects of two HRH4 agonists on steroidogenesis and proliferation. We found that HRH4 is functionally expressed in MA-10 cells, and that its activation leads to the inhibition of LH/human chorionic gonadotropin-induced cAMP production and StAR protein expression. Furthermore, we observed decreased cell proliferation after a 24-h HRH4 agonist treatment. We then detected for the sites of HRH4 expression in the normal rat testis, and detected HRH4 immunostaining in the Leydig cells of rats aged 7-240 days, while 21-day-old rats also presented HRH4 expression in male gametes. Finally, we evaluated the effect of HRH4 activation on the proliferation of normal progenitor and immature rat Leydig cell culture, and both proved to be susceptible to the anti-proliferative effect of HRH4 agonists. Given the importance of histamine (2-(1H-imidazol-4-yl)ethanamine) in human (patho)physiology, continued efforts are directed at elucidating the emerging properties of HRH4 and its ligands. This study reveals new sites of HRH4 expression, and should be considered in the design of selective HRH4 agonists for therapeutic purposes. PMID:25253872

  14. Estrogen promotes Leydig cell engulfment by macrophages in male infertility

    PubMed Central

    Yu, Wanpeng; Zheng, Han; Lin, Wei; Tajima, Astushi; Zhang, Yong; Zhang, Xiaoyan; Zhang, Hongwen; Wu, Jihua; Han, Daishu; Rahman, Nafis A.; Korach, Kenneth S.; Gao, George Fu; Inoue, Ituro; Li, Xiangdong

    2014-01-01

    Male infertility accounts for almost half of infertility cases worldwide. A subset of infertile men exhibit reduced testosterone and enhanced levels of estradiol (E2), though it is unclear how increased E2 promotes deterioration of male fertility. Here, we utilized a transgenic mouse strain that overexpresses human CYP19, which encodes aromatase (AROM+ mice), and mice with knockout of Esr1, encoding estrogen receptor α (ERαKO mice), to analyze interactions between viable Leydig cells (LCs) and testicular macrophages that may lead to male infertility. In AROM+ males, enhanced E2 promoted LC hyperplasia and macrophage activation via ERα signaling. E2 stimulated LCs to produce growth arrest–specific 6 (GAS6), which mediates phagocytosis of apoptotic cells by bridging cells with surface exposed phosphatidylserine (PS) to macrophage receptors, including the tyrosine kinases TYRO3, AXL, and MER. Overproduction of E2 increased apoptosis-independent extrusion of PS on LCs, which in turn promoted engulfment by E2/ERα-activated macrophages that was mediated by AXL-GAS6-PS interaction. We further confirmed E2-dependant engulfment of LCs by real-time 3D imaging. Furthermore, evaluation of molecular markers in the testes of patients with nonobstructive azoospermia (NOA) revealed enhanced expression of CYP19, GAS6, and AXL, which suggests that the AROM+ mouse model reflects human infertility. Together, these results suggest that GAS6 has a potential as a clinical biomarker and therapeutic target for male infertility. PMID:24762434

  15. Clinicopathologic features of ovarian Sertoli-Leydig cell tumors

    PubMed Central

    Zhang, Hai-Yan; Zhu, Jia-Er; Huang, Wen; Zhu, Jin

    2014-01-01

    Background: Ovarian Stertoli-Ledig cell tumor (SLCT) is a rare type of sex cord-stromal tumor of the ovary. The present study was to evaluate clinicalopahologic features and prognosis of patients with Sertoli-Leydig cell tumor treated by surgery and adjuvant chemotherapy during short term follow-up. Methods: A total of sixteen patients with ovarian Sertoli-Leydig cell tumor treated at the Obstetrics and Gynecology Hospital, Shanghai, China, between Jan 2001 and Dec 2011 were reviewed. The clinical data, treatment and prognosis were obtained from medical records. Results: The median age of the patients with ovarian Sertoli-Leydig cell tumor was about 27.5 years old in non-menopausal women, while the median age of menopausal women was about 63 years old. The most common complaint was with hormonal-related symptoms in the form of secondary amenorrhea and infinity, features of virilization, abdominal mass or irregular vaginal bleeding. All of sixteen patients underwent surgical staging and all were found to have stage I disease at the time of diagnosis. Eleven patients with intermediate and two patients with poorly differentiated tumors received adjuvant chemotherapy. There were differences found in operative time, blood loss and postoperative recovery time between laparotomy and laparoscopy. There were no disease-related deaths and all patients were under complete remission at the last follow-up. Conclusions: Ovarian Sertoli-Leydig cell tumors could happen in any period age of women. However, the tumors typically occur in the single side while still at the early stage, a favorable outcome could be achieved by surgery and adjuvant chemotherapy. Laparoscopy has similar surgical effects as laparotomy, but has a number of advantages. PMID:25400781

  16. Leydig cell damage after testicular irradiation for lymphoblastic leukemia

    SciTech Connect

    Shalet, S.M.; Horner, A.; Ahmed, S.R.; Morris-Jones, P.H.

    1985-01-01

    The effect of testicular irradiation on Leydig cell function has been studied in a group of boys irradiated between 1 and 5 years earlier for a testicular relapse of acute lymphoblastic leukemia. Six of the seven boys irradiated during prepubertal life had an absent testosterone response to HCG stimulation. Two of the four boys irradiated during puberty had an appropriate basal testosterone level, but the testosterone response to HCG stimulation was subnormal in three of the four. Abnormalities in gonadotropin secretion consistent with testicular damage were noted in nine of the 11 boys. Evidence of severe Leydig cell damage was present irrespective of whether the boys were studied within 1 year or between 3 and 5 years after irradiation, suggesting that recovery is unlikely. Androgen replacement therapy has been started in four boys and will be required by the majority of the remainder to undergo normal pubertal development.

  17. Phthalate-induced testicular dysgenesis syndrome: Leydig cell influence.

    PubMed

    Hu, Guo-Xin; Lian, Qing-Quan; Ge, Ren-Shan; Hardy, Dianne O; Li, Xiao-Kun

    2009-04-01

    Phthalates, the most abundantly produced plasticizers, leach out from polyvinyl chloride plastics and disrupt androgen action. Male rats that are exposed to phthalates in utero develop symptoms characteristic of the human condition referred to as testicular dysgenesis syndrome (TDS). Environmental influences have been suspected to contribute to the increasing incidence of TDS in humans (i.e. cryptorchidism and hypospadias in newborn boys and testicular cancer and reduced sperm quality in adult males). In this review, we discuss the recent findings that prenatal exposure to phthalates affects Leydig cell function in the postnatal testis. This review also focuses on the recent progress in our understanding of how Leydig cell factors contribute to phthalate-mediated TDS. PMID:19278865

  18. Pdgfr-α mediates testis cord organization and fetal Leydig cell development in the XY gonad

    PubMed Central

    Brennan, Jennifer; Tilmann, Christopher; Capel, Blanche

    2003-01-01

    During testis development, the rapid morphological changes initiated by Sry require the coordinate integration of many signaling pathways. Based on the established role of the platelet-derived growth factor (PDGF) family of ligands and receptors in migration, proliferation, and differentiation of cells in various organ systems, we have investigated the role of PDGF in testis organogenesis. Analysis of expression patterns and characterization of the gonad phenotype in Pdgfr-α−/− embryos identified PDGFR-α as a critical mediator of signaling in the early testis at multiple steps of testis development. Pdgfr-α−/− XY gonads displayed disruptions in the organization of the vasculature and in the partitioning of interstitial and testis cord compartments. Closer examination revealed severe reductions in characteristic XY proliferation, mesonephric cell migration, and fetal Leydig cell differentiation. This work identifies PDGF signaling through the α receptor as an important event downstream of Sry in testis organogenesis and Leydig cell differentiation. PMID:12651897

  19. GATA4 knockdown in MA-10 Leydig cells identifies multiple target genes in the steroidogenic pathway.

    PubMed

    Bergeron, Francis; Nadeau, Gabriel; Viger, Robert S

    2015-03-01

    GATA4 is an essential transcription factor required for the initiation of genital ridge formation, for normal testicular and ovarian differentiation at the time of sex determination, and for male and female fertility in adulthood. In spite of its crucial roles, the genes and/or gene networks that are ultimately regulated by GATA4 in gonadal tissues remain to be fully understood. This is particularly true for the steroidogenic lineages such as Leydig cells of the testis where many in vitro (promoter) studies have provided good circumstantial evidence that GATA4 is a key regulator of Leydig cell gene expression and steroidogenesis, but formal proof is still lacking. We therefore performed a microarray screening analysis of MA-10 Leydig cells in which Gata4 expression was knocked down using an siRNA strategy. Analysis identified several GATA4-regulated pathways including cholesterol synthesis, cholesterol transport, and especially steroidogenesis. A decrease in GATA4 protein was associated with decreased expression of steroidogenic genes previously suspected to be GATA4 targets such as Cyp11a1 and Star. Gata4 knockdown also led to an important decrease in other novel steroidogenic targets including Srd5a1, Gsta3, Hsd3b1, and Hsd3b6, as well as genes known to participate in cholesterol metabolism such as Scarb1, Ldlr, Soat1, Scap, and Cyp51. Consistent with the decreased expression of these genes, a reduction in GATA4 protein compromised the ability of MA-10 cells to produce steroids both basally and under hormone stimulation. These data therefore provide strong evidence that GATA4 is an essential transcription factor that sits atop of the Leydig cell steroidogenic program. PMID:25504870

  20. Annexin V-induced rat Leydig cell proliferation involves Ect2 via RhoA/ROCK signaling pathway.

    PubMed

    Jing, Jun; Chen, Li; Fu, Hai-Yan; Fan, Kai; Yao, Qi; Ge, Yi-Feng; Lu, Jin-Chun; Yao, Bing

    2015-01-01

    This study investigated the effect of annexin V on the proliferation of primary rat Leydig cells and the potential mechanism. Our results showed that annexin V promoted rat Leydig cell proliferation and cell cycle progression in a dose- and time-dependent manner. Increased level of annexin V also enhanced Ect2 protein expression. However, siRNA knockdown of Ect2 attenuated annexin V-induced proliferation of rat Leydig cells. Taken together, these data suggest that increased level of annexin V induced rat Leydig cell proliferation and cell cycle progression via Ect2. Since RhoA activity was increased following Ect2 activation, we further investigated whether Ect2 was involved in annexin V-induced proliferation via the RhoA/ROCK pathway, and the results showed that annexin V increased RhoA activity too, and this effect was abolished by the knockdown of Ect2. Moreover, inhibition of the RhoA/ROCK pathway by a ROCK inhibitor, Y27632, also attenuated annexin V-induced proliferation and cell cycle progression. We thus conclude that Ect2 is involved in annexin V-induced rat Leydig cell proliferation through the RhoA/ROCK pathway. PMID:25807302

  1. Stimulation of TM3 Leydig cell proliferation via GABAA receptors: A new role for testicular GABA

    PubMed Central

    Geigerseder, Christof; Doepner, Richard FG; Thalhammer, Andrea; Krieger, Annette; Mayerhofer, Artur

    2004-01-01

    The neurotransmitter gamma-aminobutyric acid (GABA) and subtypes of GABA receptors were recently identified in adult testes. Since adult Leydig cells possess both the GABA biosynthetic enzyme glutamate decarboxylase (GAD), as well as GABAA and GABAB receptors, it is possible that GABA may act as auto-/paracrine molecule to regulate Leydig cell function. The present study was aimed to examine effects of GABA, which may include trophic action. This assumption is based on reports pinpointing GABA as regulator of proliferation and differentiation of developing neurons via GABAA receptors. Assuming such a role for the developing testis, we studied whether GABA synthesis and GABA receptors are already present in the postnatal testis, where fetal Leydig cells and, to a much greater extend, cells of the adult Leydig cell lineage proliferate. Immunohistochemistry, RT-PCR, Western blotting and a radioactive enzymatic GAD assay evidenced that fetal Leydig cells of five-six days old rats possess active GAD protein, and that both fetal Leydig cells and cells of the adult Leydig cell lineage possess GABAA receptor subunits. TM3 cells, a proliferating mouse Leydig cell line, which we showed to possess GABAA receptor subunits by RT-PCR, served to study effects of GABA on proliferation. Using a colorimetric proliferation assay and Western Blotting for proliferating cell nuclear antigen (PCNA) we demonstrated that GABA or the GABAA agonist isoguvacine significantly increased TM3 cell number and PCNA content in TM3 cells. These effects were blocked by the GABAA antagonist bicuculline, implying a role for GABAA receptors. In conclusion, GABA increases proliferation of TM3 Leydig cells via GABAA receptor activation and proliferating Leydig cells in the postnatal rodent testis bear a GABAergic system. Thus testicular GABA may play an as yet unrecognized role in the development of Leydig cells during the differentiation of the testicular interstitial compartment. PMID:15040802

  2. Regulation of seminiferous tubule-associated stem Leydig cells in adult rat testes.

    PubMed

    Li, Xiaoheng; Wang, Zhao; Jiang, Zhenming; Guo, Jingjing; Zhang, Yuxi; Li, Chenhao; Chung, Jinyong; Folmer, Janet; Liu, June; Lian, Qingquan; Ge, Renshan; Zirkin, Barry R; Chen, Haolin

    2016-03-01

    Testicular Leydig cells are the primary source of testosterone in males. Adult Leydig cells have been shown to arise from stem cells present in the neonatal testis. Once established, adult Leydig cells turn over only slowly during adult life, but when these cells are eliminated experimentally from the adult testis, new Leydig cells rapidly reappear. As in the neonatal testis, stem cells in the adult testis are presumed to be the source of the new Leydig cells. As yet, the mechanisms involved in regulating the proliferation and differentiation of these stem cells remain unknown. We developed a unique in vitro system of cultured seminiferous tubules to assess the ability of factors from the seminiferous tubules to regulate the proliferation of the tubule-associated stem cells, and their subsequent entry into the Leydig cell lineage. The proliferation of the stem Leydig cells was stimulated by paracrine factors including Desert hedgehog (DHH), basic fibroblast growth factor (FGF2), platelet-derived growth factor (PDGF), and activin. Suppression of proliferation occurred with transforming growth factor β (TGF-β). The differentiation of the stem cells was regulated positively by DHH, lithium- induced signaling, and activin, and negatively by TGF-β, PDGFBB, and FGF2. DHH functioned as a commitment factor, inducing the transition of stem cells to the progenitor stage and thus into the Leydig cell lineage. Additionally, CD90 (Thy1) was found to be a unique stem cell surface marker that was used to obtain purified stem cells by flow cytometry. PMID:26929346

  3. AB250. Annexin V-induced rat Leydig cell proliferation involves Ect2 via RhoA/ROCK signaling pathway

    PubMed Central

    Yao, Bin

    2016-01-01

    Background This study investigated the effect of annexin V on the proliferation of primary rat Leydig cells and the potential mechanism. Methods The primary rat Leydig cells were cultured in vitro and treated with 1 nmol/L annexin 5 and with siRNA–Ect2 transfection. The cell proliferation rate was measured by MTT assay. Phase distribution of cell cycle was analyzed by flow cytometry. The expression of Ect2 in protein level were detected by western blotting. RhoA activity was measured by Rho activation assay kit. Results Our results showed that annexin V promoted rat Leydig cell proliferation and cell cycle progression in a dose- and time-dependent manner. Increased level of annexin V also enhanced Ect2 protein expression. However, siRNA knockdown of Ect2 attenuated annexin V-induced proliferation of rat Leydig cells. Taken together, these data suggest that increased level of annexin V induced rat Leydig cell proliferation and cell cycle progression via Ect2. Since RhoA activity was increased following Ect2 activation, we further investigated whether Ect2 was involved in annexin V-induced proliferation via the RhoA/ROCK pathway, and the results showed that annexin V increased RhoA activity too, and this effect was abolished by the knockdown of Ect2. Moreover, inhibition of the RhoA/ROCK pathway by a ROCK inhibitor, Y27632, also attenuated annexin V-induced proliferation and cell cycle progression. Conclusions We thus conclude that Ect2 is involved in annexin V-induced rat Leydig cell proliferation through the RhoA/ROCK pathway.

  4. The Transcription Factor MEF2 Is a Novel Regulator of Gsta Gene Class in Mouse MA-10 Leydig Cells.

    PubMed

    Di-Luoffo, Mickaël; Brousseau, Catherine; Bergeron, Francis; Tremblay, Jacques J

    2015-12-01

    Testosterone is essential for spermatogenesis and the development of male sexual characteristics. However, steroidogenesis produces a significant amount of reactive oxygen species (ROS), which can disrupt testosterone production. The myocyte enhancer factor 2 (MEF2) is an important regulator of organogenesis and cell differentiation in various tissues. In the testis, MEF2 is present in Sertoli and Leydig cells throughout fetal and adult life. MEF2-deficient MA-10 Leydig cells exhibit a significant decrease in steroidogenesis concomitant with a reduction in glutathione S-transferase (GST) activity and in the expression of the 4 Gsta members (GST) that encode ROS inactivating enzymes. Here, we report a novel role for MEF2 in ROS detoxification by directly regulating Gsta expression in Leydig cells. Endogenous Gsta1-4 mRNA levels were decreased in MEF2-deficient MA-10 Leydig cells. Conversely, overexpression of MEF2 increased endogenous Gsta1 levels. MEF2 recruitment to the proximal Gsta1 promoter and direct binding on the -506-bp MEF2 element were confirmed by chromatin immunoprecipitation and DNA precipitation assays. In MA-10 Leydig cells, MEF2 activates the Gsta1 promoter and cooperates with Ca(2+)/calmodulin-dependent kinases I to further enhance Gsta1 promoter activity. These effects were lost when the -506-bp MEF2 element was mutated or when a MEF2-Engrailed dominant negative protein was used. Similar results were obtained on the Gsta2, Gsta3, and Gsta4 promoters, suggesting a global role for MEF2 factors in the regulation of all 4 Gsta genes. Altogether, our results identify a novel role for MEF2 in the expression of genes involved in ROS detoxification, a process essential for adequate testosterone production in Leydig cells. PMID:26393304

  5. RODENT LEYDIG CELL TUMORIGENESIS: A REVIEW OF THE PHYSIOLOGY, PATHOLOGY, MECHANISMS, AND RELEVANCE TO HUMANS

    EPA Science Inventory

    Leydig cells (LCs) are the cells of the testis that have as their primary function the production of testosterone. LCs are a common target of compounds tested in rodent carcinogenicity bioassays. The number of reviews on Leydig cell tumors (LCTs) has increased in recent years bec...

  6. Apoptosome activation, an important molecular instigator in 6-mercaptopurine induced Leydig cell death

    PubMed Central

    Morgan, Jessica A.; Lynch, John; Panetta, John C.; Wang, Yao; Frase, Sharon; Bao, Ju; Zheng, Jie; Opferman, Joseph T.; Janke, Laura; Green, Daniel M.; Chemaitilly, Wassim; Schuetz, John D.

    2015-01-01

    Leydig cells are crucial to the production of testosterone in males. It is unknown if the cancer chemotherapeutic drug, 6-mercaptopurine (6 MP), produces Leydig cell failure among adult survivors of childhood acute lymphoblastic leukemia. Moreover, it is not known whether Leydig cell failure is due to either a loss of cells or an impairment in their function. Herein, we show, in a subset of childhood cancer survivors, that Leydig cell failure is related to the dose of 6 MP. This was extended, in a murine model, to demonstrate that 6 MP exposure induced caspase 3 activation, and the loss of Leydig cells was independent of Bak and Bax activation. The death of these non-proliferating cells was triggered by 6 MP metabolism, requiring formation of both cytosolic reactive oxygen species and thiopurine nucleotide triphosphates. The thiopurine nucleotide triphosphates (with physiological amounts of dATP) uniquely activated the apoptosome. An ABC transporter (Abcc4/Mrp4) reduced the amount of thiopurines, thereby providing protection for Leydig cells. The studies reported here demonstrate that the apoptosome is uniquely activated by thiopurine nucleotides and suggest that 6 MP induced Leydig cell death is likely a cause of Leydig cell failure in some survivors of childhood cancer. PMID:26576726

  7. Advanced glycation end products inhibit testosterone secretion by rat Leydig cells by inducing oxidative stress and endoplasmic reticulum stress.

    PubMed

    Zhao, Yun-Tao; Qi, Ya-Wei; Hu, Chuan-Yin; Chen, Shao-Hong; Liu, You

    2016-08-01

    Diabetes severely impairs male reproduction. The present study assessed the effects and mechanisms of action of advanced glycation end products (AGEs), which play an important role in the development of diabetes complications, on testosterone secretion by rat Leydig cells. Primary rat Leydig cells were cultured and treated with AGEs (25, 50, 100 and 200 µg/ml). Testosterone production induced by human chorionic gonadotropin (hCG) was determined by ELISA. The mRNA and protein expression levels of steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (P450scc) and 3β-hydroxysteroid dehydrogenase (3β-HSD), which are involved in testosterone biosynthesis, were measured by reverse transcription-quantitative PCR and western blot analyssi, respectively. Reactive oxygen species (ROS) production in Leydig cells was measured using the dichlorofluorescein diacetate (DCFH-DA) probe. The expression levels of endoplasmic reticulum stress-related proteins [C/EBP homologous protein (CHOP) and glucose-regulated protein 78 (GRP78)] in the Leydig cells were measured by western blot analysis. We found that the AGEs markedly suppressed testosterone production by rat Leydig cells which was induced by hCG in a concentration-dependent manner compared with the control (P<0.01). The mRNA and protein expression levels of StAR, 3β-HSD and P450scc were downregulated by the AGEs in a dose-dependent manner compared with the control (P<0.01). The antioxidant agent, N-acetyl‑L‑cysteine (NAC), and the endoplasmic reticulum stress inhibitor, tauroursodeoxycholic acid (TUDCA), reversed the inhibitory effects of AGEs. In addition, the content of ROS in Leydig cells treated with AGEs increased significantly. The expression levels of CHOP and GRP78 were markedly upregulated by the AGEs in the Leydig cells. From these findings, it can be concluded that AGEs inhibit testosterone production by rat Leydig cells by inducing oxidative stress and

  8. Effects of Etomidate on the Steroidogenesis of Rat Immature Leydig Cells

    PubMed Central

    Liu, Hua-Cheng; Zhu, Danyan; Wang, Chan; Guan, Hongguo; Li, Senlin; Hu, Cong; Chen, Zhichuan; Hu, Yuanyuan; Lin, Han; Lian, Qing-Quan; Ge, Ren-Shan

    2015-01-01

    Background Etomidate is a rapid hypnotic intravenous anesthetic agent. The major side effect of etomidate is the reduced plasma concentration of corticosteroids, leading to the abnormal reaction of adrenals. Cortisol and testosterone biosynthesis has similar biosynthetic pathway, and shares several common steroidogenic enzymes, such as P450 side chain cleavage enzyme (CYP11A1) and 3β-hydroxysteroid dehydrogenase 1 (HSD3B1). The effect of etomidate on Leydig cell steroidogenesis during the cell maturation process is not well established. Methodology Immature Leydig cells isolated from 35 day-old rats were cultured with 30 μM etomidate for 3 hours in combination with LH, 8Br-cAMP, 25R-OH-cholesterol, pregnenolone, progesterone, androstenedione, testosterone and dihydrotestosterone, respectively. The concentrations of 5α-androstanediol and testosterone in the media were measured by radioimmunoassay. Leydig cells were cultured with various concentrations of etomidate (0.3–30 μM) for 3 hours, and total RNAs were extracted. Q-PCR was used to measure the mRNA levels of following genes: Lhcgr, Scarb1, Star, Cyp11a1, Hsd3b1, Cyp17a1, Hsd17b3, Srd5a1, and Akr1c14. The testis mitochondria and microsomes from 35-day-old rat testes were prepared and used to detect the direct action of etomidate on CYP11A1 and HSD3B1 activity. Results and Conclusions In intact Leydig cells, 30 μM etomidate significantly inhibited androgen synthesis. Further studies showed that etomidate also inhibited the LH- stimulated androgen production. On purified testicular mitochondria and ER fractions, etomidate competitively inhibited both CYP11A1 and HSD3B1 activities, with the half maximal inhibitory concentration (IC50) values of 12.62 and 2.75 μM, respectively. In addition, etomidate inhibited steroidogenesis-related gene expression. At about 0.3 μM, etomidate significantly inhibited the expression of Akr1C14. At the higher concentration (30 μM), it also reduced the expression levels of

  9. Overexpression of PRL7D1 in Leydig Cells Causes Male Reproductive Dysfunction in Mice.

    PubMed

    Liu, Yaping; Su, Xingyu; Hao, Jie; Chen, Maoxin; Liu, Weijia; Liao, Xiaogang; Li, Gang

    2016-01-01

    Prolactin family 7, subfamily d, member 1 (PRL7D1) is found in mouse placenta. Our recent work showed that PRL7D1 is also present in mouse testis Leydig cells, and the expression of PRL7D1 in the testis exhibits an age-related increase. In the present study, we generated transgenic mice with Leydig cell-specific PRL7D1 overexpression to explore its function during male reproduction. Prl7d1 male mice exhibited subfertility as reflected by reduced sperm counts and litter sizes. The testes from Prl7d1 transgenic mice appeared histologically normal, but the frequency of apoptotic germ cells was increased. Prl7d1 transgenic mice also had lower testosterone concentrations than wild-type mice. Mechanistic studies revealed that Prl7d1 transgenic mice have defects in the testicular expression of steroidogenic acute regulatory protein (STAR) and hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase cluster (HSD3B). Further studies revealed that PRL7D1 overexpression affected the expression of transferrin (TF) in Sertoli cells. These results suggest that PRL7D1 overexpression could lead to increased germ cell apoptosis and exert an inhibitory effect on testosterone production in Leydig cells by reducing the expression of certain steroidogenic-related genes. In addition, PRL7D1 appears to have important roles in the function of Sertoli cells, which, in turn, affects male fertility. We conclude that the expression level of PRL7D1 is associated with the reproductive function of male mice. PMID:26771609

  10. Overexpression of PRL7D1 in Leydig Cells Causes Male Reproductive Dysfunction in Mice

    PubMed Central

    Liu, Yaping; Su, Xingyu; Hao, Jie; Chen, Maoxin; Liu, Weijia; Liao, Xiaogang; Li, Gang

    2016-01-01

    Prolactin family 7, subfamily d, member 1 (PRL7D1) is found in mouse placenta. Our recent work showed that PRL7D1 is also present in mouse testis Leydig cells, and the expression of PRL7D1 in the testis exhibits an age-related increase. In the present study, we generated transgenic mice with Leydig cell-specific PRL7D1 overexpression to explore its function during male reproduction. Prl7d1 male mice exhibited subfertility as reflected by reduced sperm counts and litter sizes. The testes from Prl7d1 transgenic mice appeared histologically normal, but the frequency of apoptotic germ cells was increased. Prl7d1 transgenic mice also had lower testosterone concentrations than wild-type mice. Mechanistic studies revealed that Prl7d1 transgenic mice have defects in the testicular expression of steroidogenic acute regulatory protein (STAR) and hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase cluster (HSD3B). Further studies revealed that PRL7D1 overexpression affected the expression of transferrin (TF) in Sertoli cells. These results suggest that PRL7D1 overexpression could lead to increased germ cell apoptosis and exert an inhibitory effect on testosterone production in Leydig cells by reducing the expression of certain steroidogenic-related genes. In addition, PRL7D1 appears to have important roles in the function of Sertoli cells, which, in turn, affects male fertility. We conclude that the expression level of PRL7D1 is associated with the reproductive function of male mice. PMID:26771609

  11. Association of cellular and molecular alterations in Leydig cells with apoptotic changes in germ cells from testes of Graomys griseoflavus×Graomys centralis male hybrids.

    PubMed

    Díaz de Barboza, Gabriela; Rodríguez, Valeria; Ponce, Rubén; Theiler, Gerardo; Maldonado, Cristina; Tolosa de Talamoni, Nori

    2014-07-01

    Spermatogenesis is disrupted in Graomys griseoflavus×Graomys centralis male hybrids. This study was aimed to determine whether morphological alterations in Leydig cells from hybrids accompany the arrest of spermatogenesis and cell death of germ cells and whether apoptotic pathways are also involved in the response of these interstitial cells. We used three groups of 1-, 2- and 3-month-old male animals: (1) G. centralis, (2) G. griseoflavus and (3) hybrids obtained by crossing G. griseoflavus females with G. centralis males. Testicular ultrastructure was analyzed by transmission electron microscopy. TUNEL was studied using an in situ cell death detection kit and the expression of apoptotic molecules by immunohistochemistry. The data confirmed arrest of spermatogenesis and intense apoptotic processes of germ cells in hybrids. These animals also showed ultrastructural alterations in the Leydig cells. Fas, FasL and calbindin D28k overexpression without an increase in DNA fragmentation was detected in the Leydig cells from hybrids. In conclusion, the sterility of Graomys hybrids occurs with ultrastructural changes in germ and Leydig cells. The enhancement of Fas and FasL is not associated with cell death in the Leydig cells. Probably the apoptosis in these interstitial cells is inhibited by the high expression of the antiapoptotic molecule calbindin D28k. PMID:24894511

  12. Cell interactions and genetic regulation that contribute to testicular Leydig cell development and differentiation.

    PubMed

    Martin, Luc J

    2016-06-01

    Leydig cells, located within the interstitial compartment of the testis, are major contributors of androgen synthesis and secretion, which play an important role in testis development, normal masculinization, maintenance of spermatogenesis, and general male fertility. Accordingly, dysfunction of Leydig cells may lead to various male reproductive maladies, including primary hypogonadism, cryptorchidism, and hypospadias. A better understanding of how cell interactions and gene regulation contribute to testicular Leydig cell development and differentiation may therefore help limit the incidence of such male reproductive pathologies. Several hormones and signaling molecules have been identified as important regulators of Leydig cell differentiation and function. Recent work on the regulation of testis development, especially of Leydig cells, has focused on the Desert hedgehog and platelet-derived growth factor signaling pathways. This review outlines recent findings regarding cell interactions and gene regulation involved in the development and regulation of fetal and adult Leydig cell populations. Mol. Reprod. Dev. 83: 470-487, 2016. © 2016 Wiley Periodicals, Inc. PMID:27079813

  13. Mycotoxin zearalenone induces apoptosis in mouse Leydig cells via an endoplasmic reticulum stress-dependent signalling pathway.

    PubMed

    Lin, Pengfei; Chen, Fenglei; Sun, Jin; Zhou, Jinhua; Wang, Xiangguo; Wang, Nan; Li, Xiao; Zhang, Zhe; Wang, Aihua; Jin, YaPing

    2015-04-01

    Zearalenone (ZEN) is a Fusarium mycotoxin that causes several reproductive disorders and genotoxic effects. This study demonstrated the involvement of endoplasmic reticulum (ER) stress in ZEN-induced mouse Leydig cell death. Our study showed that ZEN reduced cell proliferation in a murine Leydig tumour cell line in a dose-dependent manner. The involvement of apoptosis as a major cause of ZEN-induced cell death was further confirmed by the results of a caspase-3 activity assay, which showed a ZEN dose-dependent increase in cell death. Treatment of MLTC-1 and primary mouse Leydig cells with ZEN upregulated the expression of the ER stress-typical markers GRP78, CHOP and caspase-12 protein. Further, pre-treating the cells with 4-phenylbutyrate or knocking down GRP78 using lentivirus-encoded shRNA significantly diminished ZEN-induced apoptosis and inhibited the expression of CHOP and caspase-12. In summary, these results suggest that the activation of an ER stress pathway plays a key role in ZEN-induced apoptosis in the mouse Leydig cells. PMID:25720297

  14. Stimulatory effects of combined endocrine disruptors on MA-10 Leydig cell steroid production and lipid homeostasis.

    PubMed

    Jones, Steven; Boisvert, Annie; Naghi, Andrada; Hullin-Matsuda, Françoise; Greimel, Peter; Kobayashi, Toshihide; Papadopoulos, Vassilios; Culty, Martine

    2016-04-29

    Previous work in our laboratory demonstrated that in-utero exposure to a mixture of the phytoestrogen Genistein (GEN), and plasticizer DEHP, induces short- and long-term alterations in testicular gene and protein expression different from individual exposures. These studies identified fetal and adult Leydig cells as sensitive targets for low dose endocrine disruptor (ED) mixtures. To further investigate the direct effects and mechanisms of toxicity of GEN and DEHP, MA-10 mouse tumor Leydig cells were exposed in-vitro to varying concentrations of GEN and MEHP, the principal bioactive metabolite of DEHP. Combined 10μM GEN+10μM MEHP had a stimulatory effect on basal progesterone production. Consistent with increased androgenicity, the mRNA of steroidogenic and cholesterol mediators Star, Cyp11a, Srb1 and Hsl, as well as upstream orphan nuclear receptors Nr2f2 and Sf1 were all significantly increased uniquely in the mixture treatment group. Insl3, a sensitive marker of Leydig endocrine disruption and cell function, was significantly decreased by combined GEN+MEHP. Lipid analysis by high-performance thin layer chromatography demonstrated the ability of combined 10μM combined GEN+MEHP, but not individual exposures, to increase levels of several neutral lipids and phospholipid classes, indicating a generalized deregulation of lipid homeostasis. Further investigation by qPCR analysis revealed a concomitant increase in cholesterol (Hmgcoa) and phospholipid (Srebp1c, Fasn) mediator mRNAs, suggesting the possible involvement of upstream LXRα agonism. These results suggest a deregulation of MA-10 Leydig function in response to a combination of GEN+MEHP. We propose a working model for GEN+MEHP doses relevant to human exposure involving LXR agonism and activation of other transcription factors. Taken more broadly, this research highlights the importance of assessing the impact of ED mixtures in multiple toxicological models across a range of environmentally relevant doses

  15. Anabolic-androgenic steroids induce apoptosis and NOS2 (nitric-oxide synthase 2) in adult rat Leydig cells following in vivo exposure.

    PubMed

    Janjic, Marija M; Stojkov, Natasa J; Andric, Silvana A; Kostic, Tatjana S

    2012-12-01

    Anabolic-androgenic steroids (AAS) are synthetic derivatives of testosterone (T) predominantly taken as drugs of abuse. Using in vivo treatment of adult male rats we investigated the effects of testosterone enanthate (TE) a widely abused AAS, on apoptosis of Leydig cells. Increased T and decreased luteinizing hormone levels in serum and decreased intra-testicular T values were found in 2 and 10 weeks treated groups. Two weeks of TE-treatment stimulated the expression of inducible nitric oxide synthase (NOS2) followed by increased NO production, decreased mitochondrial membrane potential and increased prevalence of Leydig cell apoptosis. This was prevented by in vivo administration of androgen receptor blocker. The induced NOS2 level and apoptosis returned to control levels after 10 weeks of TE-treatment but testes contained fewer Leydig cells. Overall, AAS in addition to reduced steroidogenesis induce transient increase of Leydig cells apoptotic rate through mechanism associated with androgen receptor, most likely involving NOS2 induction. PMID:23085480

  16. Role of peroxiredoxin 2 in H2O2‑induced oxidative stress of primary Leydig cells.

    PubMed

    Duan, Ting; Fan, Kai; Chen, Shengrong; Yao, Qi; Zeng, Rong; Hong, Zhiwei; Peng, Longping; Shao, Yong; Yao, Bing

    2016-06-01

    Late‑onset hypogonadism is defined as a condition caused by a decline in the levels of testosterone with aging. One of the major factors contributing to the low levels of testosterone is the accumulation of reactive oxygen species (ROS) in Leydig cells during the ageing process. Peroxiredoxin 2 (Prdx2), a member of the peroxiredoxin family, is an antioxidant protein, the predominant function of which is to neutralize ROS. However, its role in Leydig cells remains to be elucidated. In the present study, primary Leydig cells were exposed to low concentrations of hydrogen peroxide (H2O2) to induce oxidative stress. Cell apoptosis was measured using an Annexin V fluorescein isothiocyanate/propidium iodide apoptosis detection kit and flow cytometry. The level of testosterone was determined by radioimmunoassay, and the mRNA and protein expression levels of Prdx2 were detected by reverse transcription‑polymerase chain reaction and western blotting, respectively. The results revealed a significant increase in cell apoptosis and decrease in testosterone production. In addition, the expression of Prdx2 was decreased by H2O2 in a dose‑ and time‑dependent manner, and this decrease may have been caused by the induction of its molecular structure transformation due to H2O2 elimination. The above findings indicated that Prdx2 may prevent H2O2 accumulation in Leydig cells, and may be important in oxidative stress‑induced apoptosis and decreased testosterone production. PMID:27082744

  17. Primary culture of purified Leydig cells isolated from adult rat testes.

    PubMed

    Browning, J Y; Heindel, J J; Grotjan, H E

    1983-02-01

    Methods for isolating highly purified Leydig cells permit the study of acute responses and biochemical properties of Leydig cells independent of other testicular cell types. The present study describes the development of a primary culture system for purified Leydig cells from adult rats in which the cells retain their ability to secrete testosterone for at least 72 h in culture. When Leydig cells were cultured in tissue culture medium 199--0.1% BSA (M199-BSA), basal testosterone secretion declined by 72 h, whereas hCGB-stimulated testosterone secretion was reduced by 48 h. Changing the culture medium twice daily or adding 0.5% fetal calf serum (fcs) enhanced basal and gonadotropin-stimulated testosterone secretion at 72 h in culture, although responsiveness to hCG was reduced to 57% of that in freshly isolated cells. Incubation of Leydig cells in the defined culture medium Dulbecco's Modified Eagles-Ham's F-12 (1:1, vol/vol) supplemented with 15 mM Hepes buffer, transferrin, insulin, and epidermal growth factor (DHG:F12 + Hepes + TIE) in either the presence or absence of 0.5% fcs yielded functional Leydig cells for longer intervals in culture. Furthermore, testosterone secretion was greater in DHG:F12 + Hepes + TIE than in M199-BSA at all time intervals tested. In DHG:F12 + Hepes + TIE, basal and gonadotropin-stimulated testosterone production by Leydig cells were maintained for 72 h in culture. Degenerative changes in morphology were apparent in some cells at 72 h, but not at earlier times in culture. This primary culture system for isolated Leydig cells provides a valuable tool to examine the temporally regulated events in Leydig cell function. PMID:6848362

  18. A potential role for zinc transporter 7 in testosterone synthesis in mouse Leydig tumor cells.

    PubMed

    Chu, Qingqing; Chi, Zhi-Hong; Zhang, Xiuli; Liang, Dan; Wang, Xuemei; Zhao, Yue; Zhang, Li; Zhang, Ping

    2016-06-01

    Previous studies have demonstrated that zinc (Zn) is an essential trace element which is involved in male reproduction. The zinc transporter (ZnT) family, SLC30a, is involved in the maintenance of Zn homeostasis and in mediating intracellular signaling events; however, relatively little is known regarding the effect of ZnTs on testosterone synthesis. Thus, in the present study, we aimed to determine the effect of Zn transporter 7 (ZnT7) on testosterone synthesis in male CD-1 mice and mouse Leydig cells. The findings of the present study revealed that the concentrations of Zn in the testes and Leydig cells were significantly lower in mice fed a Zn-deficient diet compared with the control mice fed a Zn-adequate diet. In addition, ZnT7 was principally expressed and colocalized with steroidogenic acute regulatory protein (StAR) in the Leydig cells of male CD-1 mice. ZnT7 expression was downregulated in the mice fed a Zn-deficient diet, which led to decreases in the expression of the enzymes involved in testosterone synthesis namely cholesterol side‑chain cleavage enzyme (P450scc) and 3β-hydroxysteroid dehydrogenase/D5-D4 isomerase (3β-HSD) as well as decreased serum testosterone levels. These results suggested that Znt7 may be involved in testosterone synthesis in the mouse testes. To examine this hypothesis, we used the mouse Leydig tumor cell line (MLTC-1 cell line) in which the ZnT7 gene had been silenced, in order to gauge the impact of changes in ZnT7 expression on testosterone secretion and the enzymes involved in testosterone synthesis. The results demonstrated that ZnT7 gene silencing downregulated the expression of StAR, P450scc and 3β-HSD as well as progesterone concentrations in the human chorionic gonadotrophin (hCG)-stimulated MLTC-1 cells. Taken together, these findings reveal that ZnT7 may play an important role in the regulation of testosterone synthesis by modulating steroidogenic enzymes, and may represent a therapeutic target in

  19. Deficiency of CDKN1A or Both CDKN1A and CDKN1B Affects the Pubertal Development of Mouse Leydig Cells1

    PubMed Central

    Lin, Han; Huang, Yadong; Su, Zhijian; Zhu, Qiqi; Ge, Yufei; Wang, Guimin; Wang, Claire Q.F.; Mukai, Motoko; Holsberger, Denise R.; Cooke, Paul S.; Lian, Qing-Quan; Ge, Ren-Shan

    2015-01-01

    ABSTRACT Cyclin-dependent kinase inhibitors p21Cip1 (CDKN1A) and p27Kip1 (CDKN1B) are expressed in Leydig cells. Previously, we reported that Cdkn1b knockout in the mouse led to increased Leydig cell proliferative capacity and lower steroidogenesis. However, the relative importance of CDKN1A and CDKN1B in these regulations was unclear. In the present study, we examined the relative importance of CDKN1A and CDKN1B in regulation of Leydig cell proliferation and steroidogenesis by whole-body knockout of CDKN1A (Cdkn1a−/−) and CDKN1A/CDKN1B double knockout (DBKO). The cell number, 5-bromo-2-deoxyuridine incorporation rate, steroidogenesis, and steroidogenic enzyme mRNA levels and activities of Leydig cells were compared among wild-type (WT), Cdkn1a−/−, and DBKO mice. Relative to WT mice, Leydig cell number per testis was doubled in the DBKO and unchanged in the Cdkn1a−/− mice. Testicular testosterone levels and mRNA levels for luteinizing hormone receptor (Lhcgr), steroidogenic acute regulatory protein (Star), cholesterol side-chain cleavage enzyme (Cyp11a1), 17alpha-hydroxylase/17,20-lyase (Cyp17a1), and 17beta-hydroxysteroid dehydrogenase 3 (Hsd17b3) and their respective proteins were significantly lower in the DBKO mice. However, testicular testosterone level was unchanged in the Cdkn1a−/− mice, although Lhcgr mRNA levels were significantly lower relative to those in the WT control. We conclude that Cdkn1a−/− did not increase Leydig cell numbers (although a defect of Leydig cell function was noted), whereas DBKO caused a significant increase of Leydig cell numbers but a decrease of steroidogenesis. PMID:25609837

  20. Protective Effect of Adrenomedullin on Rat Leydig Cells from Lipopolysaccharide-Induced Inflammation and Apoptosis via the PI3K/Akt Signaling Pathway ADM on Rat Leydig Cells from Inflammation and Apoptosis.

    PubMed

    Zhou, Pang-Hu; Hu, Wei; Zhang, Xiao-Bin; Wang, Wei; Zhang, Li-Jun

    2016-01-01

    This study was carried out to investigate whether ADM can modulate LPS-induced inflammation and apoptosis in rat Leydig cells. Leydig cells were treated with ADM before LPS-induced cytotoxicity. We determined the concentrations of ROS, MDA, GSH, LDH, and testosterone and the MMP. The mRNA levels of IL-1, IL-6, iNOS, and COX-2 were obtained, and the concentrations of IL-1, IL-6, NO, and PGE2 were determined. Apoptosis was assessed by TUNEL and detection of DNA fragmentation. The levels of mRNA and protein were determined for Bcl-2, Bax, caspase-3, and PARP. The protein contents for total and p-Akt were measured. ADM pretreatment significantly elevated the MMP and testosterone concentration and reduced the levels of ROS, MDA, GSH, and LDH. ADM pretreatment significantly decreased the mRNA levels of IL-1, IL-6, iNOS, and COX-2 and the concentrations of IL-1, IL-6, NO, and PGE2. LPS-induced TUNEL-positive Leydig cells were significantly decreased by ADM pretreatment, a result further confirmed by decreased DNA fragmentation. ADM pretreatment decreased apoptosis by significantly promoting Bcl-2 and inhibiting Bax, caspase-3, and PARP expressions. The LPS activity that reduced p-Akt level was significantly inhibited by ADM pretreatment. ADM protected rat Leydig cells from LPS-induced inflammation and apoptosis, which might be associated with PI3K/Akt mitochondrial signaling pathway. PMID:27212810

  1. Protective Effect of Adrenomedullin on Rat Leydig Cells from Lipopolysaccharide-Induced Inflammation and Apoptosis via the PI3K/Akt Signaling Pathway ADM on Rat Leydig Cells from Inflammation and Apoptosis

    PubMed Central

    Zhou, Pang-Hu; Hu, Wei; Zhang, Xiao-Bin; Wang, Wei; Zhang, Li-Jun

    2016-01-01

    This study was carried out to investigate whether ADM can modulate LPS-induced inflammation and apoptosis in rat Leydig cells. Leydig cells were treated with ADM before LPS-induced cytotoxicity. We determined the concentrations of ROS, MDA, GSH, LDH, and testosterone and the MMP. The mRNA levels of IL-1, IL-6, iNOS, and COX-2 were obtained, and the concentrations of IL-1, IL-6, NO, and PGE2 were determined. Apoptosis was assessed by TUNEL and detection of DNA fragmentation. The levels of mRNA and protein were determined for Bcl-2, Bax, caspase-3, and PARP. The protein contents for total and p-Akt were measured. ADM pretreatment significantly elevated the MMP and testosterone concentration and reduced the levels of ROS, MDA, GSH, and LDH. ADM pretreatment significantly decreased the mRNA levels of IL-1, IL-6, iNOS, and COX-2 and the concentrations of IL-1, IL-6, NO, and PGE2. LPS-induced TUNEL-positive Leydig cells were significantly decreased by ADM pretreatment, a result further confirmed by decreased DNA fragmentation. ADM pretreatment decreased apoptosis by significantly promoting Bcl-2 and inhibiting Bax, caspase-3, and PARP expressions. The LPS activity that reduced p-Akt level was significantly inhibited by ADM pretreatment. ADM protected rat Leydig cells from LPS-induced inflammation and apoptosis, which might be associated with PI3K/Akt mitochondrial signaling pathway. PMID:27212810

  2. Molecular Mechanisms Elicited by d-Aspartate in Leydig Cells and Spermatogonia

    PubMed Central

    Di Fiore, Maria Maddalena; Santillo, Alessandra; Falvo, Sara; Longobardi, Salvatore; Chieffi Baccari, Gabriella

    2016-01-01

    A bulk of evidence suggests that d-aspartate (d-Asp) regulates steroidogenesis and spermatogenesis in vertebrate testes. This review article focuses on intracellular signaling mechanisms elicited by d-Asp possibly via binding to the N-methyl-d-aspartate receptor (NMDAR) in both Leydig cells, and spermatogonia. In Leydig cells, the amino acid upregulates androgen production by eliciting the adenylate cyclase-cAMP and/or mitogen-activated protein kinase (MAPK) pathways. d-Asp treatment enhances gene and protein expression of enzymes involved in the steroidogenic cascade. d-Asp also directly affects spermatogonial mitotic activity. In spermatogonial GC-1 cells, d-Asp induces phosphorylation of MAPK and AKT serine-threonine kinase proteins, and stimulates expression of proliferating cell nuclear antigen (PCNA) and aurora kinase B (AURKB). Further stimulation of spermatogonial GC-1 cell proliferation might come from estradiol/estrogen receptor β (ESR2) interaction. d-Asp modulates androgen and estrogen levels as well as the expression of their receptors in the rat epididymis by acting on mRNA levels of Srd5a1 and Cyp19a1 enzymes, hence suggesting involvement in spermatozoa maturation. PMID:27428949

  3. Molecular Mechanisms Elicited by d-Aspartate in Leydig Cells and Spermatogonia.

    PubMed

    Di Fiore, Maria Maddalena; Santillo, Alessandra; Falvo, Sara; Longobardi, Salvatore; Chieffi Baccari, Gabriella

    2016-01-01

    A bulk of evidence suggests that d-aspartate (d-Asp) regulates steroidogenesis and spermatogenesis in vertebrate testes. This review article focuses on intracellular signaling mechanisms elicited by d-Asp possibly via binding to the N-methyl-d-aspartate receptor (NMDAR) in both Leydig cells, and spermatogonia. In Leydig cells, the amino acid upregulates androgen production by eliciting the adenylate cyclase-cAMP and/or mitogen-activated protein kinase (MAPK) pathways. d-Asp treatment enhances gene and protein expression of enzymes involved in the steroidogenic cascade. d-Asp also directly affects spermatogonial mitotic activity. In spermatogonial GC-1 cells, d-Asp induces phosphorylation of MAPK and AKT serine-threonine kinase proteins, and stimulates expression of proliferating cell nuclear antigen (PCNA) and aurora kinase B (AURKB). Further stimulation of spermatogonial GC-1 cell proliferation might come from estradiol/estrogen receptor β (ESR2) interaction. d-Asp modulates androgen and estrogen levels as well as the expression of their receptors in the rat epididymis by acting on mRNA levels of Srd5a1 and Cyp19a1 enzymes, hence suggesting involvement in spermatozoa maturation. PMID:27428949

  4. Isolation and Characterization of Fetal Leydig Progenitor Cells of Male Mice.

    PubMed

    Inoue, Miki; Shima, Yuichi; Miyabayashi, Kanako; Tokunaga, Kaori; Sato, Tetsuya; Baba, Takashi; Ohkawa, Yasuyuki; Akiyama, Haruhiko; Suyama, Mikita; Morohashi, Ken-Ichirou

    2016-03-01

    Fetal and adult Leydig cells develop in mammalian prenatal and postnatal testes, respectively. In mice, fetal Leydig cells (FLCs) emerge in the interstitial space of the testis at embryonic day 12.5 and thereafter increase in number, possibly through differentiation from progenitor cells. However, the progenitor cells have not yet been identified. Previously, we established transgenic mice in which FLCs are labeled strongly with enhanced green fluorescent protein (EGFP). Interestingly, fluorescence-activated cell sorting provided us with weakly EGFP-labeled cells as well as strongly EGFP-labeled FLCs. In vitro reconstruction of fetal testes demonstrated that weakly EGFP-labeled cells contain FLC progenitors. Transcriptome from the 2 cell populations revealed, as expected, marked differences in the expression of genes required for growth factor/receptor signaling and steroidogenesis. In addition, genes for energy metabolisms such as glycolytic pathways and the citrate cycle were activated in strongly EGFP-labeled cells, suggesting that metabolism is activated during FLC differentiation. PMID:26697723

  5. Astaxanthin protects steroidogenesis from hydrogen peroxide-induced oxidative stress in mouse Leydig cells.

    PubMed

    Wang, Jyun-Yuan; Lee, Yue-Jia; Chou, Mei-Chia; Chang, Renin; Chiu, Chih-Hsien; Liang, Yao-Jen; Wu, Leang-Shin

    2015-03-01

    Androgens, especially testosterone produced in Leydig cells, play an essential role in development of the male reproductive phenotype and fertility. However, testicular oxidative stress may cause a decline in testosterone production. Many antioxidants have been used as reactive oxygen species (ROS) scavengers to eliminate oxidative stress to protect steroidogenesis. Astaxanthin (AST), a natural extract from algae and plants ubiquitous in the marine environment, has been shown to have antioxidant activity in many previous studies. In this study, we treated primary mouse Leydig cells or MA-10 cells with hydrogen peroxide (H2O2) to cause oxidative stress. Testosterone and progesterone production was suppressed and the expression of the mature (30 kDa) form of StAR protein was down-regulated in MA-10 cells by H2O2 and cAMP co-treatment. However, progesterone production and expression of mature StAR protein were restored in MA-10 cells by a one-hour pretreatment with AST. AST also reduced ROS levels in cells so that they were lower than the levels in untreated controls. These results provide additional evidence of the potential health benefits of AST as a potential food additive to ease oxidative stress. PMID:25786065

  6. Astaxanthin Protects Steroidogenesis from Hydrogen Peroxide-Induced Oxidative Stress in Mouse Leydig Cells

    PubMed Central

    Wang, Jyun-Yuan; Lee, Yue-Jia; Chou, Mei-Chia; Chang, Renin; Chiu, Chih-Hsien; Liang, Yao-Jen; Wu, Leang-Shin

    2015-01-01

    Androgens, especially testosterone produced in Leydig cells, play an essential role in development of the male reproductive phenotype and fertility. However, testicular oxidative stress may cause a decline in testosterone production. Many antioxidants have been used as reactive oxygen species (ROS) scavengers to eliminate oxidative stress to protect steroidogenesis. Astaxanthin (AST), a natural extract from algae and plants ubiquitous in the marine environment, has been shown to have antioxidant activity in many previous studies. In this study, we treated primary mouse Leydig cells or MA-10 cells with hydrogen peroxide (H2O2) to cause oxidative stress. Testosterone and progesterone production was suppressed and the expression of the mature (30 kDa) form of StAR protein was down-regulated in MA-10 cells by H2O2 and cAMP co-treatment. However, progesterone production and expression of mature StAR protein were restored in MA-10 cells by a one-hour pretreatment with AST. AST also reduced ROS levels in cells so that they were lower than the levels in untreated controls. These results provide additional evidence of the potential health benefits of AST as a potential food additive to ease oxidative stress. PMID:25786065

  7. Green tea polyphenols inhibit testosterone production in rat Leydig cells

    PubMed Central

    Figueiroa, Marina S; César Vieira, Juliany S B; Leite, Disleide S; Filho, Ruben C O Andrade; Ferreira, Fabiano; Gouveia, Patrícia S; Udrisar, Daniel P; Wanderley, Maria I

    2009-01-01

    This study investigated the acute effects of green tea extract (GTE) and its polyphenol constituents, (−)-epigallocatechin-3-gallate (EGCG) and (−)-epicatechin (EC), on basal and stimulated testosterone production by rat Leydig cells in vitro. Leydig cells purified in a Percoll gradient were incubated for 3 h with GTE, EGCG or EC and the testosterone precursor androstenedione, in the presence or absence of either protein kinase A (PKA) or protein kinase C (PKC) activators. The reversibility of the effect was studied by pretreating cells for 15 min with GTE or EGCG, allowing them to recover for 1 h and challenging them for 2 h with human chorionic gonadotropin (hCG), luteinizing hormone releasing hormone (LHRH), 22(R)-hydroxycholesterol or androstenedione. GTE and EGCG, but not EC, inhibited both basal and kinase-stimulated testosterone production. Under the pretreatment conditions, the inhibitory effect of the higher concentration of GTE/EGCG on hCG/LHRH-stimulated or 22(R)-hydroxycholesterol-induced testosterone production was maintained, whereas androstenedione-supported testosterone production returned to control levels. At the lower concentration of GTE/EGCG, the inhibitory effect of these polyphenols on 22(R)-hydroxycholesterol-supported testosterone production was reversed. The inhibitory effects of GTE may be explained by the action of its principal component, EGCG, and the presence of a gallate group in its structure seems important for its high efficacy in inhibiting testosterone production. The mechanisms underlying the effects of GTE and EGCG involve the inhibition of the PKA/PKC signalling pathways, as well as the inhibition of P450 side-chain cleavage enzyme and 17β-hydroxysteroid dehydrogenase function. PMID:19330017

  8. Effect of chronic treatment with Rosiglitazone on Leydig cell steroidogenesis in rats: In vivo and ex vivo studies

    PubMed Central

    2010-01-01

    Background The present study was designed to examine the effect of chronic treatment with rosiglitazone - thiazolidinedione used in the treatment of type 2 diabetes mellitus for its insulin sensitizing effects - on the Leydig cell steroidogenic capacity and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal adult rats. Methods Twelve adult male Wistar rats were treated with rosiglitazone (5 mg/kg) administered by gavage for 15 days. Twelve control animals were treated with the vehicle. The ability of rosiglitazone to directly affect the production of testosterone by Leydig cells ex vivo was evaluated using isolated Leydig cells from rosiglitazone-treated rats. Testosterone production was induced either by activators of the cAMP/PKA pathway (hCG and dbcAMP) or substrates of steroidogenesis [22(R)-hydroxy-cholesterol (22(R)-OH-C), which is a substrate for the P450scc enzyme, and pregnenolone, which is the product of the P450scc-catalyzed step]. Testosterone in plasma and in incubation medium was measured by radioimmunoassay. The StAR and P450scc expression was detected by immunocytochemistry. Results The levels of total circulating testosterone were not altered by rosiglitazone treatment. A decrease in basal or induced testosterone production occurred in the Leydig cells of rosiglitazone-treated rats. The ultrastructural and immunocytochemical analysis of Leydig cells from rosiglitazone-treated rats revealed cells with characteristics of increased activity as well as increased StAR and P450scc expression, which are key proteins in androgen biosynthesis. However, a number of rosiglitazone-treated cells exhibited significant mitochondrial damage. Conclusion The results revealed that the Leydig cells from rosiglitazone-treated rats showed significant reduction in testosterone production under basal, hCG/dbcAMP- or 22 (R)-OH-C/pregnenolone-induced conditions, although increased labeling of St

  9. Evidence for genetic heterogeneity in male pseudohermaphroditism due to Leydig cell hypoplasia.

    PubMed

    Zenteno, J C; Canto, P; Kofman-Alfaro, S; Mendez, J P

    1999-10-01

    Leydig cell aplasia or hypoplasia is a rare form of male pseudohermaphroditism resulting from inadequate fetal testicular Leydig cell differentiation. Affected individuals presented a wide phenotypic spectrum, ranging from complete female external genitalia to males with micropenis. Recessive mutations in the LH receptor gene have been identified as responsible for the condition. The majority of these mutations are point mutations and have been located in exon 11 of the gene. In this study, we report the molecular characterization of the LH receptor gene in three siblings with Leydig cell hypoplasia. After sequencing the 11 exons of the gene, no deleterious mutations were detected in any patient. However, we identified a previously described polymorphism in exon 11. In patients 1 and 3 DNA sequencing revealed a C to T substitution at nucleotide 1065; both patients were homozygous GAT/GAT at codon 355. In contrast, patient 2 was homozygous GAC/GAC, whereas the father and one unaffected sister were heterozygous GAC/GAT at this polymorphic site. These results exclude that Leydig cell hypoplasia in this family is due to a mutation in the LH receptor gene and provide evidence that defects in other loci may also result in failure of Leydig cell differentiation, demonstrating, for the first time, that Leydig cell hypoplasia is a genetically heterogeneous condition. PMID:10523033

  10. Specific destruction of Leydig cells in mature rats after in vivo administration of ethane dimethyl sulfonate.

    PubMed

    Molenaar, R; de Rooij, D G; Rommerts, F F; Reuvers, P J; van der Molen, H J

    1985-12-01

    Effects of ethane dimethyl sulfonate (EDS) on Leydig cells have been studied using the following parameters: morphology, histochemistry of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and esterase, quantitative activity of esterase, testosterone concentrations in plasma, and steroid production by isolated interstitial cells in vitro. Degenerating Leydig cells were observed within 16 h after the injection of mature rats with EDS (75 mg/kg body weight). At that time the testosterone concentration in plasma and the specific activity of esterase in testis tissue were decreased to approximately 35% and 60% of the control value, respectively. At 48 h after EDS only a few normal Leydig cells were left and the plasma testosterone concentration was less than 5% of the control value. The specific activity of esterase in total testis tissue was similar to the activity of dissected tubules from untreated rats. At 72 h no Leydig cells could be detected and no 3 beta-HSD and esterase-positive cells were present. At that time macrophages were still present in the interstitium and the appearance of the spermatogenic epithelium was normal, but 1 wk after EDS the elongation of spermatids was disturbed, probably due to a lack of testosterone. In some of the animals the cytotoxic effects of EDS on Leydig cells could be partly inhibited by human chorionic gonadotropin treatment. The basal steroid production by interstitial cells from mature rats 72 h after EDS was not significant and no stimulation by LH was observed, whereas no effect of EDS could be detected on steroid production by interstitial cells isolated from immature rats and mice 72 h after treatment. Other compounds with similar structures, such as butane dimethyl sulfonate (busulfan) and ethane methyl sulfonate (EMS) had no effect on Leydig cells from mature rats. It is concluded that EDS specifically destroys Leydig cells in mature rats. PMID:3000465

  11. Insulin Directly Regulates Steroidogenesis via Induction of the Orphan Nuclear Receptor DAX-1 in Testicular Leydig Cells*

    PubMed Central

    Ahn, Seung Won; Gang, Gil-Tae; Kim, Yong Deuk; Ahn, Ryun-Sup; Harris, Robert A.; Lee, Chul-Ho; Choi, Hueng-Sik

    2013-01-01

    Testosterone level is low in insulin-resistant type 2 diabetes. Whether this is due to negative effects of high level of insulin on the testes caused by insulin resistance has not been studied in detail. In this study, we found that insulin directly binds to insulin receptors in Leydig cell membranes and activates phospho-insulin receptor-β (phospho-IR-β), phospho-IRS1, and phospho-AKT, leading to up-regulation of DAX-1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1) gene expression in the MA-10 mouse Leydig cell line. Insulin also inhibits cAMP-induced and liver receptor homolog-1 (LRH-1)-induced steroidogenic enzyme gene expression and steroidogenesis. In contrast, knockdown of DAX-1 reversed insulin-mediated inhibition of steroidogenesis. Whether insulin directly represses steroidogenesis through regulation of steroidogenic enzyme gene expression was assessed in insulin-injected mouse models and high fat diet-induced obesity. In insulin-injected mouse models, insulin receptor signal pathway was activated and subsequently inhibited steroidogenesis via induction of DAX-1 without significant change of luteinizing hormone or FSH levels. Likewise, the levels of steroidogenic enzyme gene expression and steroidogenesis were low, but interestingly, the level of DAX-1 was high in the testes of high fat diet-fed mice. These results represent a novel regulatory mechanism of steroidogenesis in Leydig cells. Insulin-mediated induction of DAX-1 in Leydig cells of testis may be a key regulatory step of serum sex hormone level in insulin-resistant states. PMID:23589295

  12. Involution of human fetal Leydig cells. An immunohistochemical, ultrastructural and quantitative study.

    PubMed Central

    Codesal, J; Regadera, J; Nistal, M; Regadera-Sejas, J; Paniagua, R

    1990-01-01

    The testes of stillborn fetuses (from 13 to 28 weeks of gestational age), fetuses born alive (from 29 weeks of gestational age) who died a few days later, and infants dying 1 to 8 months after birth were processed for light and electron microscopy. Paraffin-embedded material was stained with the avidin-biotin peroxidase complex (ABC) method for immunohistochemical detection of testosterone (T) in order to quantify the age-related changes in the number of T-positive interstitial cells. This number decreased progressively from the 24th week of gestation up to birth and remained unchanged up to the second month of postnatal life. During the third month of age, the number of T-positive cells rose markedly but fell again from the fourth month to the end of the study. The ultrastructural study revealed the following types of interstitial cells at all ages studied: fibroblast-like cells, myofibroblast-like cells, developed fetal Leydig cells, degenerating fetal Leydig cells and infantile Leydig cells with a multilobed nucleus and focal cytoplasmic accumulations of smooth endoplasmic reticulum and lipid droplets. Quantitative ultrastructural studies revealed that the changes in the number of fetal Leydig cells with age were similar to those found in the number of T-positive cells although, for each age studied, absolute values were higher in the ultrastructural study. The number of infantile Leydig cells increased with age. Images Figs. 1-4 Figs. 5-9 Figs. 10-11 PMID:2272896

  13. Combined steroidogenic characters of fetal adrenal and Leydig cells in childhood adrenocortical carcinoma.

    PubMed

    Fujisawa, Yasuko; Sakaguchi, Kimiyoshi; Ono, Hiroyuki; Yamaguchi, Rie; Kato, Fumiko; Kagami, Masayo; Fukami, Maki; Ogata, Tsutomu

    2016-05-01

    Although childhood adrenocortical carcinomas (c-ACCs) with a TP53 mutation are known to produce androgens, detailed steroidogenic characters have not been clarified. Here, we examined steroid metabolite profiles and expression patterns of steroidogenic genes in a c-ACC removed from the left adrenal position of a 2-year-old Brazilian boy with precocious puberty, using an atrophic left adrenal gland removed at the time of tumorectomy as a control. The c-ACC produced not only abundant dehydroepiandrosterone-sulfate but also a large amount of testosterone via the Δ5 pathway with Δ5-androstenediol rather than Δ4-androstenedione as the primary intermediate metabolite. Furthermore, the c-ACC was associated with elevated expressions of CYP11A1, CYP17A1, POR, HSD17B3, and SULT2A1, a low but similar expression of CYB5A, and reduced expressions of AKR1C3 (HSD17B5) and HSD3B2. Notably, a Leydig cell marker INSL3 was expressed at a low but detectable level in the c-ACC. Furthermore, molecular studies revealed a maternally inherited heterozygous germline TP53 mutation, and several post-zygotic genetic aberrations in the c-ACC including loss of paternally derived chromosome 17 with a wildtype TP53 and loss of maternally inherited chromosome 11 and resultant marked hyperexpression of paternally expressed growth promoting gene IGF2 and drastic hypoexpression of maternally expressed growth suppressing gene CDKN1C. These results imply the presence of combined steroidogenic properties of fetal adrenal and Leydig cells in this patient's c-ACC with a germline TP53 mutation and several postzygotic carcinogenic events. PMID:26940356

  14. Effects of hypoxia on testosterone release in rat Leydig cells.

    PubMed

    Hwang, Guey-Shyang; Chen, Szu-Tah; Chen, Te-Jung; Wang, Shyi-Wu

    2009-11-01

    The aim of this study was to explore the effect and action mechanisms of intermittent hypoxia on the production of testosterone both in vivo and in vitro. Male rats were housed in a hypoxic chamber (12% O(2) + 88% N(2), 1.5 l/ml) 8 h/day for 4 days. Normoxic rats were used as control. In an in vivo experiment, hypoxic and normoxic rats were euthanized and the blood samples collected. In the in vitro experiment, the enzymatically dispersed rat Leydig cells were prepared and challenged with forskolin (an adenylyl cyclase activator, 10(-4) M), 8-Br-cAMP (a membrane-permeable analog of cAMP, 10(-4) M), hCG (0.05 IU), the precursors of the biosynthesis testosterone, including 25-OH-C (10(-5) M), pregnenolone (10(-7) M), progesterone (10(-7) M), 17-OH-progesterone (10(-7) M), and androstendione (10(-7)-10(-5) M), nifedipine (L-type Ca(2+) channel blocker, 10(-6)-10(-4) M), nimodipine (L-type Ca(2+) channel blocker, 10(-5) M), tetrandrine (L-type Ca(2+) channel blocker, 10(-5) M), and NAADP (calcium-signaling messenger causing release of calcium from intracellular stores, 10(-6)-10(-4) M). The concentrations of testosterone in plasma and medium were measured by radioimmunoassay. The level of plasma testosterone in hypoxic rats was higher than that in normoxic rats. Enhanced testosterone production was observed in rat Leydig cells treated with hCG, 8-Br-cAMP, or forskolin in both normoxic and hypoxic conditions. Intermittent hypoxia resulted in a further increase of testosterone production in response to the testosterone precursors. The activity of 17β-hydroxysteroid dehydrogenase was stimulated by the treatment of intermittent hypoxia in vitro. The intermittent hypoxia-induced higher production of testosterone was accompanied with the influx of calcium via L-type calcium channel and the increase of intracellular calcium via the mechanism of calcium mobilization. These results suggested that the intermittent hypoxia stimulated the secretion of testosterone at least in

  15. Disturbance in Testosterone Production in Leydig Cells by Polycyclic Aromatic Hydevrepocarbons

    PubMed Central

    Oh, Seunghoon

    2014-01-01

    Polycyclic aromatic hydevrepocarbons (PAHs), which are ubiquitous in the air, are present as volatile and particulate pollutants that result from incomplete combustion. Most PAHs have toxic, mutagenic, and/or carcinogenic properties. Among PAHs, benzo[a]pyrene (B[a]P) and dimethylbenz[a]anthracene (DMBA) are suspected endocrine disruptors. The testis is an important target for PAHs, yet effects on steroidogenesis in Leydig cells are yet to be ascertained. Particularly, disruption of testosterone production by these chemicals can result in serious defects in male reproduction. Exposure to B[a]P reduced serum and intratesticular fluid testosterone levels in rats. Of note, the testosterone level reductions were accompanied by decreased steroidogenic acute regulatory protein (StAR) and 3β-hydevrepoxysteroid dehydevrepogenase isomerase (3β-HSD) expression in Leydig cells. B[a]P exposure can decrease epididymal sperm quality, possibly by disturbing the testosterone level. StAR may be a key steroidogenic protein that is targeted by B[a]P or other PAHs. PMID:25949189

  16. Comparison of the Effects of Dibutyl and Monobutyl Phthalates on the Steroidogenesis of Rat Immature Leydig Cells

    PubMed Central

    Li, Linxi; Chen, Xiaomin; Hu, Guoxin; Wang, Sicong; Xu, Renai; Zhu, Qiqi; Li, Xiaoheng; Wang, Mingcang; Lian, Qing-Quan; Ge, Ren-Shan

    2016-01-01

    Dibutyl phthalate (DBP) is a widely used synthetic phthalic diester and monobutyl phthalate (MBP) is its main metabolite. DBP can be released into the environment and potentially disrupting mammalian male reproductive endocrine system. However, the potencies of DBP and MBP to inhibit Leydig cell steroidogenesis and their possible mechanisms are not clear. Immature Leydig cells isolated from rats were cultured with 0.05–50 μM DBP or MBP for 3 h in combination with testosterone synthesis regulator or intermediate. The concentrations of 5α-androstanediol and testosterone in the media were measured, and the mRNA levels of the androgen biosynthetic genes were detected by qPCR. The direct actions of DBP or MBP on CYP11A1, CYP17A1, SRD5A1, and AKR1C14 activities were measured. MBP inhibited androgen production by the immature Leydig cell at as low as 50 nM, while 50 μM was required for DBP to suppress its androgen production. MBP mainly downregulated Cyp11a1 and Hsd3b1 expression levels at 50 nM. However, 50 μM DBP downregulated Star, Hsd3b1, and Hsd17b3 expression levels and directly inhibited CYP11A1 and CYP17A1 activities. In conclusion, DBP is metabolized to more potent inhibitor MBP that downregulated the expression levels of some androgen biosynthetic enzymes. PMID:27148549

  17. Comparison of the Effects of Dibutyl and Monobutyl Phthalates on the Steroidogenesis of Rat Immature Leydig Cells.

    PubMed

    Li, Linxi; Chen, Xiaomin; Hu, Guoxin; Wang, Sicong; Xu, Renai; Zhu, Qiqi; Li, Xiaoheng; Wang, Mingcang; Lian, Qing-Quan; Ge, Ren-Shan

    2016-01-01

    Dibutyl phthalate (DBP) is a widely used synthetic phthalic diester and monobutyl phthalate (MBP) is its main metabolite. DBP can be released into the environment and potentially disrupting mammalian male reproductive endocrine system. However, the potencies of DBP and MBP to inhibit Leydig cell steroidogenesis and their possible mechanisms are not clear. Immature Leydig cells isolated from rats were cultured with 0.05-50 μM DBP or MBP for 3 h in combination with testosterone synthesis regulator or intermediate. The concentrations of 5α-androstanediol and testosterone in the media were measured, and the mRNA levels of the androgen biosynthetic genes were detected by qPCR. The direct actions of DBP or MBP on CYP11A1, CYP17A1, SRD5A1, and AKR1C14 activities were measured. MBP inhibited androgen production by the immature Leydig cell at as low as 50 nM, while 50 μM was required for DBP to suppress its androgen production. MBP mainly downregulated Cyp11a1 and Hsd3b1 expression levels at 50 nM. However, 50 μM DBP downregulated Star, Hsd3b1, and Hsd17b3 expression levels and directly inhibited CYP11A1 and CYP17A1 activities. In conclusion, DBP is metabolized to more potent inhibitor MBP that downregulated the expression levels of some androgen biosynthetic enzymes. PMID:27148549

  18. HBCDD-induced sustained reduction in mitochondrial membrane potential, ATP and steroidogenesis in peripubertal rat Leydig cells

    SciTech Connect

    Fa, Svetlana; Pogrmic-Majkic, Kristina; Samardzija, Dragana; Hrubik, Jelena; Glisic, Branka; Kovacevic, Radmila; Andric, Nebojsa

    2015-01-01

    Hexabromocyclododecane (HBCDD), a brominated flame retardant added to various consumer products, is a ubiquitous environmental contaminant. We have previously shown that 6-hour exposure to HBCDD disturbs basal and human chorionic gonadotropin (hCG)-induced steroidogenesis in rat Leydig cells. Reduction in mitochondrial membrane potential (ΔΨm) and cAMP production was also observed. Here, we further expanded research on the effect of HBCDD on Leydig cells by using a prolonged exposure scenario. Cells were incubated in the presence of HBCDD during 24 h and then treated with HBCDD + hCG for additional 2 h. Results showed that HBCDD caused a sustained reduction in ATP level after 24 h of exposure, which persisted after additional 2-hour treatment with HBCDD + hCG. cAMP and androgen accumulations measured after 2 h of HBCDD + hCG treatment were also inhibited. Real-time PCR analysis showed significant inhibition in the expression of genes for steroidogenic enzymes, luteinizing hormone receptor, regulatory and transport proteins, and several transcription factors under both treatment conditions. Western blot analysis revealed a decreased level of 30 kDa steroidogenic acute regulatory protein (StAR) after HBCDD + hCG treatment. In addition, HBCDD decreased the conversion of 22-OH cholesterol to pregnenolone and androstenedione to testosterone, indicating loss of the activity of cytochrome P450C11A1 (CYP11A1) and 17β-hydroxysteroid dehydrogenase (HSD17β). Cell survival was not affected, as confirmed by cytotoxicity and trypan blue tests or DNA fragmentation analysis. In summary, our data showed that HBCDD inhibits ATP supply, most likely through a decrease in ΔΨm, and targets multiple sites in the steroidogenic pathway in Leydig cells. - Highlights: • HBCDD causes a sustained reduction in ΔΨm and ATP level in Leydig cells. • Prolonged HBCDD exposure decreases hCG-supported steroidogenesis in Leydig cells. • HBCDD targets StAR, HSD17β and CYP11A1 in Leydig

  19. Effects of Nandrolone Stimulation on Testosterone Biosynthesis in Leydig Cells.

    PubMed

    Pomara, Cristoforo; Barone, Rosario; Marino Gammazza, Antonella; Sangiorgi, Claudia; Barone, Fulvio; Pitruzzella, Alessandro; Locorotondo, Nicola; Di Gaudio, Francesca; Salerno, Monica; Maglietta, Francesca; Sarni, Antonio Luciano; Di Felice, Valentina; Cappello, Francesco; Turillazzi, Emanuela

    2016-06-01

    Anabolic androgenic steroids (AAS) are among the drugs most used by athletes for improving physical performance, as well as for aesthetic purposes. A number of papers have showed the side effects of AAS in different organs and tissues. For example, AAS are known to suppress gonadotropin-releasing hormone, luteinizing hormone, and follicle-stimulating hormone. This study investigates the effects of nandrolone on testosterone biosynthesis in Leydig cells using various methods, including mass spectrometry, western blotting, confocal microscopy and quantitative real-time PCR. The results obtained show that testosterone levels increase at a 3.9 μM concentration of nandrolone and return to the basal level a 15.6 μM dose of nandrolone. Nandrolone-induced testosterone increment was associated with upregulation of the steroidogenic acute regulatory protein (StAR) and downregulation of 17a-hydroxylase/17, 20 lyase (CYP17A1). Instead, a 15.6 µM dose of nandrolone induced a down-regulation of CYP17A1. Further in vivo studies based on these data are needed to better understand the relationship between disturbed testosterone homeostasis and reproductive system impairment in male subjects. PMID:26626779

  20. Changes in mouse Leydig cell steroidogenesis following infrared and helium-neon laser irradiation.

    PubMed

    Celani, M F; Grandi, M; Gilioli, G

    1987-03-01

    The effects on mouse Leydig cell steroidogenesis of infrared (IR) laser rays, in the presence or absence of helium-neon (He-Ne) radiations, were investigated. Testosterone (T) production in response to luteinizing hormone (LH) by mouse Leydig cells exposed to IR (4.2 X 10(-3) J/cm2/min) plus He-Ne (8.0 X 10(-7) J/cm2/min) laser radiations was significantly higher than that by control Leydig cells. The Leydig cell responsiveness to LH (T delta %), as well as the secretion of cyclic AMP (cAMP) and androstenedione (A) in response to the highest dose of LH (0.5 mIU), were also significantly increased by the IR plus He-Ne irradiation. In contrast, the He-Ne irradiation (8.0 X 10(-7) J/cm2/min) in the absence of IR rays failed to affect T production by mouse Leydig cells. Similar results were obtained by adding to the He-Ne rays a low dose of IR radiation (3.4 X 10(-3) J/cm2/min), whereas higher doses of IR radiations (4.2 X 10(-3) and 5.1 X 10(-3) J/cm2/min) elicited a similar significant increase of T production by mouse interstitial cells. PMID:3595730

  1. Phthalate ester toxicity in Leydig cells: developmental timing and dosage considerations.

    PubMed

    Ge, Ren-Shan; Chen, Guo-Rong; Tanrikut, Cigdem; Hardy, Matthew P

    2007-01-01

    Humans have significant exposures to phthalates, as these chemical plasticizers are ubiquitously present in flexible plastics. Recent epidemiological evidence indicates that boys born to women exposed to phthalates during pregnancy have an increased incidence of congenital genital malformations and spermatogenic dysfunction, signs of a condition referred to as testicular dysgenesis syndrome (TDS). TDS is thought to develop as a result of environmental factors that cause a testicular disturbance at an early fetal stage with a resultant spectrum of clinical testicular dysfunction, ranging from impaired spermatogenesis and genital malformations to increased risk for development of testicular cancer. Proposed environmental factors in the etiology of TDS include endocrine disrupting compounds such as the phthalates. Leydig cells have been classified as one of the main targets for phthalate ester toxicity in the body based on studies in rodents. In support of this hypothesis, two Leydig cell products - insulin-like growth factor 3 (INSL3) and testosterone (T) - are both suppressed after phthalate exposures. Both fetal and adult generations of Leydig cells are affected by phthalate esters, although their sensitivities may differ. In rodent models, when pregnant dams are exposed to phthalate esters, fetal Leydig cells form enlarged clusters that are retained in the testis even after birth, in contrast to untreated controls. Despite the retention of fetal Leydig cells, however, their numbers and average cell volume of total in exposed males are reduced, as are INSL3 production and steroidogenic competence. These alterations are directly associated with clinical features of TDS, including cryptorchidism and impaired spermatogenesis. PMID:17258888

  2. Studying mechanisms of cAMP and cyclic nucleotide phosphodiesterase signaling in Leydig cell function with phosphoproteomics.

    PubMed

    Golkowski, Martin; Shimizu-Albergine, Masami; Suh, Hyong Won; Beavo, Joseph A; Ong, Shao-En

    2016-07-01

    Many cellular processes are modulated by cyclic AMP and nucleotide phosphodiesterases (PDEs) regulate this second messenger by catalyzing its breakdown. The major unique function of testicular Leydig cells is to produce testosterone in response to luteinizing hormone (LH). Treatment of Leydig cells with PDE inhibitors increases cAMP levels and the activity of its downstream effector, cAMP-dependent protein kinase (PKA), leading to a series of kinase-dependent signaling and transcription events that ultimately increase testosterone release. We have recently shown that PDE4B and PDE4C as well as PDE8A and PDE8B are expressed in rodent Leydig cells and that combined inhibition of PDE4 and PDE8 leads to dramatically increased steroid biosynthesis. Here we investigated the effect of PDE4 and PDE8 inhibition on the molecular mechanisms of cAMP actions in a mouse MA10 Leydig cell line model with SILAC mass spectrometry-based phosphoproteomics. We treated MA10 cells either with PDE4 family specific inhibitor (Rolipram) and PDE8 family specific inhibitor (PF-04957325) alone or in combination and quantified the resulting phosphorylation changes at five different time points between 0 and 180min. We identified 28,336 phosphosites from 4837 proteins and observed significant regulation of 749 sites in response to PDE4 and PDE8 inhibitor treatment. Of these, 132 phosphosites were consensus PKA sites. Our data strongly suggest that PDE4 and PDE8 inhibitors synergistically regulate phosphorylation of proteins required for many different cellular processes, including cell cycle progression, lipid and glucose metabolism, transcription, endocytosis and vesicle transport. Our data suggests that cAMP, PDE4 and PDE8 coordinate steroidogenesis by acting on not one rate-limiting step but rather multiple pathways. Moreover, the pools of cAMP controlled by these PDEs also coordinate many other metabolic processes that may be regulated to assure timely and sufficient testosterone secretion

  3. In utero exposure to phthalate downregulates critical genes in Leydig cells of F1 male progeny.

    PubMed

    Sekaran, Suganya; Jagadeesan, Arunakaran

    2015-07-01

    Phthalates are the largest group of environmental pollutants and are considered toxicant to the endocrine system. The present study was aimed to test the effect of in utero exposure of di(2-ethylhexyl)phthalate (DEHP) on Leydig cell steroidogenesis in F1 male offspring's. Pregnant dams were oral gavaged with different doses (1, 10, and 100 mg/kg/day) of DEHP or olive oil during gestational Day 9-21. Serum testosterone (T) and estradiol (E2) levels were significantly reduced in male offspring at 60 days of age. Our results also demonstrate a coordinate, dose-dependent disruption of genes involved in steroidogenesis. The gene expression of StAR, Cyp11a1, 3β-HSD, 17β-HSD, 5α-reductase and cytochrome P450 19a1 (or) aromatase (Cyp-19) were significantly decreased. The transcription factors like steroidogenic factor-1 (SF-1) and specific protein-1 (Sp-1) showed a significant decrease in 10 and 100 mg DEHP treatment group. DNA methylation analysis using bisulfite specific-methylation PCR shows hypermethylation in the SF-1 and Sp-1 promoter regions. Further to determine whether the DEHP-induced methylation changes were associated with increased DNA methyltransferase (Dnmt) levels, we measured the expression levels of Dnmt3a, Dnmt3b, Dnmt1, and Dnmt3l using real-time PCR and Western blot method. The mRNA and protein expressions of Dnmt3a, Dnmt3b, and Dnmt1 were stimulated in 10 and 100 mg DEHP treatment groups, whereas no significant change was seen in Dnmt3l expression, suggesting that increased Dnmt3a/b, Dnmt1 may cause DNA hypermethylation in testicular Leydig cells. Overall, these data suggest that gestational exposure to DEHP affects adult testicular function via altered methylation patterns. PMID:25649163

  4. The mechanism for lindane-induced inhibition of steroidogenesis in cultured rat Leydig cells.

    PubMed

    Ronco, A M; Valdés, K; Marcus, D; Llanos, M

    2001-02-21

    The in vitro effect of the gamma-isomer of hexachlorocyclohexane, lindane, on rat Leydig cell steroidogenesis was studied. Leydig cells from mature male rats were incubated with human chorionic gonadotropin (hCG, 1 IU) for 3 h at 34 degrees C in the presence of different doses of lindane (2-200 microg/ml; 2-200 ppm). Results demonstrate that lindane produces a dose-dependent inhibition of testosterone production in hCG-stimulated Leydig cells. The decreased testosterone synthesis was accompanied with a half-reduced LH/hCG receptor number without any modification in the K(d) value. In addition, lindane also decreased cAMP production. These effects were not due to a detrimental action of lindane on cell viability. Results of this study demonstrate a direct inhibitory action of lindane on testicular steroidogenesis, at least in part, through a reduction in the classical second messenger production involved in this pathway. PMID:11250058

  5. Effects of the Methanol Extract of Basella alba L (Basellaceae) on Steroid Production in Leydig Cells

    PubMed Central

    Nantia, Edouard Akono; Travert, Carine; Manfo, Faustin-Pascal T.; Carreau, Serge; Monsees, Thomas K.; Moundipa, Paul Fewou

    2011-01-01

    In this study, Leydig cells were purified from 70 day-old Sprague Dawley male rats and incubated with 10 and 100 μg/mL of methanol extract of Basella alba (MEBa) for 4 hours followed by the evaluation of cell viability, steroid (testosterone and estradiol) production, and the level of aromatase mRNA. Results showed that MEBa did not affect Leydig cell viability. At the concentration of 10 μg/mL, MEBa significantly stimulated testosterone and estradiol production (p < 0.01 and p < 0.03, respectively), and enhanced aromatase mRNA level (p < 0.04). These observations suggest that MEBa directly stimulated testosterone, estradiol and aromatase mRNA levels in isolated Leydig cells. PMID:21339992

  6. Effects of the methanol extract of Basella alba L (Basellaceae) on steroid production in Leydig cells.

    PubMed

    Nantia, Edouard Akono; Travert, Carine; Manfo, Faustin-Pascal T; Carreau, Serge; Monsees, Thomas K; Moundipa, Paul Fewou

    2011-01-01

    In this study, Leydig cells were purified from 70 day-old Sprague Dawley male rats and incubated with 10 and 100 μg/mL of methanol extract of Basella alba (MEBa) for 4 hours followed by the evaluation of cell viability, steroid (testosterone and estradiol) production, and the level of aromatase mRNA. Results showed that MEBa did not affect Leydig cell viability. At the concentration of 10 μg/mL, MEBa significantly stimulated testosterone and estradiol production (p < 0.01 and p < 0.03, respectively), and enhanced aromatase mRNA level (p < 0.04). These observations suggest that MEBa directly stimulated testosterone, estradiol and aromatase mRNA levels in isolated Leydig cells. PMID:21339992

  7. Fetal programming of adult Leydig cell function by androgenic effects on stem/progenitor cells

    PubMed Central

    Kilcoyne, Karen R.; Smith, Lee B.; Atanassova, Nina; Macpherson, Sheila; McKinnell, Chris; van den Driesche, Sander; Jobling, Matthew S.; Chambers, Thomas J. G.; De Gendt, Karel; Verhoeven, Guido; O’Hara, Laura; Platts, Sophie; Renato de Franca, Luiz; Lara, Nathália L. M.; Anderson, Richard A.; Sharpe, Richard M.

    2014-01-01

    Fetal growth plays a role in programming of adult cardiometabolic disorders, which in men, are associated with lowered testosterone levels. Fetal growth and fetal androgen exposure can also predetermine testosterone levels in men, although how is unknown, because the adult Leydig cells (ALCs) that produce testosterone do not differentiate until puberty. To explain this conundrum, we hypothesized that stem cells for ALCs must be present in the fetal testis and might be susceptible to programming by fetal androgen exposure during masculinization. To address this hypothesis, we used ALC ablation/regeneration to identify that, in rats, ALCs derive from stem/progenitor cells that express chicken ovalbumin upstream promoter transcription factor II. These stem cells are abundant in the fetal testis of humans and rodents, and lineage tracing in mice shows that they develop into ALCs. The stem cells also express androgen receptors (ARs). Reduction in fetal androgen action through AR KO in mice or dibutyl phthalate (DBP) -induced reduction in intratesticular testosterone in rats reduced ALC stem cell number by ∼40% at birth to adulthood and induced compensated ALC failure (low/normal testosterone and elevated luteinizing hormone). In DBP-exposed males, this failure was probably explained by reduced testicular steroidogenic acute regulatory protein expression, which is associated with increased histone methylation (H3K27me3) in the proximal promoter. Accordingly, ALCs and ALC stem cells immunoexpressed increased H3K27me3, a change that was also evident in ALC stem cells in fetal testes. These studies highlight how a key component of male reproductive development can fundamentally reprogram adult hormone production (through an epigenetic change), which might affect lifetime disease risk. PMID:24753613

  8. Specific protein synthesis in isolated rat testis leydig cells. Influence of luteinizing hormone and cycloheximide.

    PubMed Central

    Janszen, F H; Cooke, B A; van der Molen, H J

    1977-01-01

    The effect of luteinizing hormone (luteotropin) and cycloheximide on specific protein synthesis in rat testis Leydig cells has been investigated. Proteins were labelled with either I114C]leucine, [3H]leucine or [35S]methionine during incubation with Leydig-cell suspensions in vitro. Total protein was extracted from the cells and separated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. No detectable increase in the synthesis of specific proteins could be observed after incubation of Leydig cells with luteinizing hormone for up to 1 h. However, after a 2h incubation period, an increase in [35S]methionine incorporation was observed in a protein with an apparent mol.wt. of 21000 (referred to as 'protein 21"). When, after labelling of this protein with [35S]-methionine, Leydig cells were incubated for another 30min with cycloheximide, no decrease in radioactivity of this protein band was observed, indicating that it does not have a short half-life. However, another protein band was detected, which after incubation with cycloheximide disappeared rapidly, the reaction following first-order kinetics, with a half-life of about 11 min. This protein, with an apparent mol.wt. of 33000 (referred to as "protein 33"), was found to be located in the particulate fraction of the Leydig cell, and could not be demonstrated in other rat testis-cell types or blood cells. No effect of luteinizing hormone on molecular weight, subcellular localization or half-life of protein 33 was observed. A possible role for protein 33 and protein 21 in the mechanism of action of luteinizing hormone on testosterone production of Leydig cells is discussed. Images PLATE 4 PLATE 1 PLATE 2 PLATE 3 PMID:849289

  9. Species-specific mechanism in rat Leydig cell tumorigenesis by procymidone.

    PubMed

    Murakami, M; Hosokawa, S; Yamada, T; Harakawa, M; Ito, M; Koyama, Y; Kimura, J; Yoshitake, A; Yamada, H

    1995-04-01

    To clarify the mechanism of species difference in the induction of testicular interstitial cell tumor (ICT, Leydig cell tumor) between rats and mice, male Sprague-Dawley rats and ICR mice were fed procymidone at dietary concentrations of 700, 2000 or 6000 ppm and 1000, 5000, or 10,000 ppm, respectively, for 3 months. The Leydig cell functions were evaluated by serum testosterone and luteinizing hormone (LH) levels, testosterone levels in the testis, LH levels in the pituitary, the capacity of the testis to respond to gonadotropin stimulation, i.e., the production of testosterone in vitro, and by the testicular binding of labeled human chorionic gonadotropin (hCG). Measurement of testosterone and LH levels in rat serum, the testis, or the pituitary showed that both hormones were enhanced throughout the 3-month treatment period. The hypergonadotropism was associated with the increase of interstitial cell response to hCG in vitro for up to 3 months. As with rats, both serum and pituitary LH were increased in mice at 4 weeks but not at 13 weeks. However, in contrast to rats, no significant increase in testosterone was observed in mice either in vivo or ex vivo during the course of the study. This suggests a difference between the rat and mouse in the response of the Leydig cell to the LH stimulation associated with procymidone administration. These differences in the response of interstitial cells to procymidone may be the basis for the distinct species responses to procymidone-induced Leydig cell tumorigenesis. The sustained response of the Leydig cells to stimulation in the rat results in chronic hyperplasia and subsequent benign tumor formation, while the attenuated response of Leydig cells in the mouse is associated with neither hyperplasia nor neoplasia. PMID:7716766

  10. Sertoli–Leydig cell tumor of the ovary: A diagnostic dilemma

    PubMed Central

    Liggins, Casandra A.; Ma, Ly T.; Schlumbrecht, Matthew P.

    2015-01-01

    Background Sertoli–Leydig cell tumors are rare sex-cord stromal tumors of the ovary that can present with a variety of histological elements, which may complicate diagnosis and treatment. Case A 40-year-old female presenting with pelvic pain is found to have a large complex right adnexal mass and elevated alpha-fetoprotein. The mass was diagnosed as a Sertoli–Leydig cell tumor with heterologous elements including carcinoid and hepatoid components. She was treated with surgical resection followed by adjuvant chemotherapy and remains clear of disease. Conclusion Prognostic indicators for Sertoli–Leydig cell tumors include degree and type of heterologous element differentiation. Thorough characterization of such elements is crucial for adequate diagnosis and treatment. PMID:26937481

  11. ACBD2/ECI2-Mediated Peroxisome-Mitochondria Interactions in Leydig Cell Steroid Biosynthesis.

    PubMed

    Fan, Jinjiang; Li, Xinlu; Issop, Leeyah; Culty, Martine; Papadopoulos, Vassilios

    2016-07-01

    Fatty acid metabolism and steroid biosynthesis are 2 major pathways shared by peroxisomes and mitochondria. Both organelles are in close apposition to the endoplasmic reticulum, with which they communicate via interorganelle membrane contact sites to promote cellular signaling and the exchange of ions and lipids. To date, no convincing evidence of the direct contact between peroxisomes and mitochondria was reported in mammalian cells. Hormone-induced, tightly controlled steroid hormone biosynthesis requires interorganelle interactions. Using immunofluorescent staining and live-cell imaging, we found that dibutyryl-cAMP treatment of MA-10 mouse tumor Leydig cells rapidly induces peroxisomes to approach mitochondria and form peroxisome-mitochondrial contact sites/fusion, revealed by the subcellular distribution of the endogenous acyl-coenzyme A-binding domain (ACBD)2/ECI2 isoform A generated by alternative splicing, and further validated using a proximity ligation assay. This event occurs likely via a peroxisome-like structure, which is mediated by peroxisomal and mitochondrial matrix protein import complexes: peroxisomal import receptor peroxisomal biogenesis factor 5 (PEX5), and the mitochondrial import receptor subunit translocase of outer mitochondrial membrane 20 homolog (yeast) protein. Similar results were obtained using the mLTC-1 mouse tumor Leydig cells. Ectopic expression of the ACBD2/ECI2 isoform A in MA-10 cells led to increased basal and hormone-stimulated steroid formation, indicating that ACBD2/ECI2-mediated peroxisomes-mitochondria interactions favor in the exchange of metabolites and/or macromolecules between these 2 organelles in support of steroid biosynthesis. Considering the widespread occurrence of the ACBD2/ECI2 protein, we propose that this protein might serve as a tool to assist in understanding the contact between peroxisomes and mitochondria. PMID:27167610

  12. Involvement of KLF14 and egr-1 in the TGF-beta1 action on Leydig cell proliferation.

    PubMed

    Gonzalez, C R; Vallcaneras, S S; Calandra, R S; Gonzalez Calvar, S I

    2013-02-01

    Transforming growth factor β1 (TGF-β1) is a pleiotropic cytokine that modulates cell homeostasis. In Leydig cells, TGF-β1 exerts stimulatory and inhibitory effect depending on the type I receptor involved in the signaling pathway. The aim of the present work was to study the signaling mechanisms and the intermediates involved in the action of TGF-β1 on TM3 Leydig cell proliferation in the presence or absence of progesterone. The MTT assay showed that the presence of progesterone in the culture media lead to a proliferative effect that was blocked by Ru 486, an inhibitor of progesterone receptor; and ALK-5 did not participate in this effect. TGF-β1 (1 ng/ml) increased the expression of p15 (an inhibitor of cell cycle) in TM3 Leydig cells, and this effect was blocked by progesterone (1μM). The expression of PCNA presented a higher increase in the cell cultured with TGF-β1 plus progesterone than in cells cultured only with TGF-β1. Progesterone induced the gene expression of endoglin, a cofactor of TGF-β1 receptor that leads to a stimulatory signaling pathway, despite of the absence of progesterone response element in endoglin gene. In addition, the presence of progesterone induced the gene expression of egr-1 and also KLF14, indicating that this steroid channels the signaling pathway into a non-canonical mechanism. In conclusion, these findings suggest that the proliferative action of TGF-β1 involves endoglin. This co-receptor might be induced by KLF14 which is probably activated by progesterone. PMID:23317878

  13. KLF6 cooperates with NUR77 and SF1 to activate the human INSL3 promoter in mouse MA-10 leydig cells.

    PubMed

    Tremblay, Maxime A; Mendoza-Villarroel, Raifish E; Robert, Nicholas M; Bergeron, Francis; Tremblay, Jacques J

    2016-04-01

    Insulin-like 3 (INSL3), a Leydig cell-specific hormone, is essential for testis descent during foetal life and bone metabolism in adults. Despite its essential roles in male reproductive and bone health, very little is known regarding its transcriptional regulation in Leydig cells. To date, few transcription factors have been shown to activate INSL3 promoter activity: the nuclear receptors AR, NUR77, COUP-TFII and SF1. To identify additional regulators, we have isolated and performed a detailed analysis of a 1.1 kb human INSL3 promoter fragment. Through 5' progressive deletions and site-directed mutagenesis, we have mapped a 10 bp element responsible for about 80% of INSL3 promoter activity in Leydig cells. This element is identical to the CPE element of the placental-specific glycoprotein-5 (PSG5) promoter that is recognized by the developmental regulator Krüppel-like factor 6 (KLF6). Using PCR and western blotting, we found that KLF6 is expressed in several Leydig and Sertoli cell lines. Furthermore, immunohistochemistry on adult mouse testis revealed the presence of KLF6 in the nuclei of both Leydig and Sertoli cells. KLF6 binds to the 10 bp KLF element at -108 bp and activates the -1.1 kb human, but not the mouse, INSL3 promoter. KLF6-mediated activation of the human INSL3 promoter required an intact KLF element as well as Leydig/Sertoli-enriched factors because KLF6 did not stimulate the human INSL3 promoter activity in CV-1 fibroblast cells. Consistent with this, we found that KLF6 transcriptionally cooperates with NUR77 and SF1. Collectively, our results identify KLF6 as a regulator of human INSL3 transcription. PMID:26874000

  14. Leydig cells contribute to the inhibition of spermatogonial differentiation after irradiation of the rat.

    PubMed

    Shetty, G; Zhou, W; Weng, C C Y; Shao, S H; Meistrich, M L

    2016-05-01

    Irradiation with 6 Gy produces a complete block of spermatogonial differentiation in LBNF1 rats that would be permanent without treatment. Subsequent suppression of gonadotropins and testosterone (T) restores differentiation to the spermatocyte stage; however, this process requires 6 weeks. We evaluated the role of Leydig cells (LCs) in maintenance of the block in spermatogonial differentiation after exposure to radiation by specifically eliminating functional LCs with ethane dimethane sulfonate (EDS). EDS (but not another alkylating agent), given at 10 weeks after irradiation, induced spermatogonial differentiation in 24% of seminiferous tubules 2 weeks later. However, differentiation became blocked again at 4 weeks as LCs recovered. When EDS was followed by treatment with GnRH antagonist and flutamide, sustained spermatogonial differentiation was induced in >70% of tubules within 2 weeks. When EDS was followed by GnRH antagonist plus exogenous T, which also inhibits LC recovery but restores follicle stimulating hormone (FSH) levels, the spermatogonial differentiation was again rapid but transient. These results confirm that the factors that block spermatogonial differentiation are indirectly regulated by T, and probably FSH, and that adult and possibly immature LCs contribute to the production of such inhibitory factors. We tested whether insulin-like 3 (INSL3), a LC-produced protein whose expression correlated with the block in spermatogonial differentiation, was indeed responsible for the block by injecting synthetic INSL3 into the testes and knocking down its expression in vivo with siRNA. Neither treatment had any effect on spermatogonial differentiation. The Leydig cell products that contribute to the inhibition of spermatogonial differentiation in irradiated rats remain to be elucidated. PMID:26991593

  15. MAINTENANCE OF TESTOSTERONE PRODUCTION BY PURIFIED ADULT RAT LEYDIG CELLS FOR THREE DAYS IN VITRO

    EPA Science Inventory

    Using a preparation of highly purified, adult rat Leydig cells and conditions of culture which we found to optimize testosterone production during 24 h, we sought to maintain optimal testosterone production for 3 d. eydig cells cultured on Cytodex 3 beads at 19% O2 in Dulbecco's ...

  16. Cadmium-induced damage to primary cultures of rat Leydig cells.

    PubMed

    Yang, Jian-Ming; Arnush, Marc; Chen, Qiong-Yu; Wu, Xiang-Dong; Pang, Bing; Jiang, Xue-Zhi

    2003-01-01

    The mechanism of testicular toxicity of cadmium is poorly understood. Previous studies focusing on cadmium-related changes in testicular histopathology have implicated testicular blood vessel damage as the main cause of cadmium toxicity. To further explore the toxic effects of cadmium on testis, we isolated and cultured rat Leydig cells, exposed to 10, 20, and 40 microM of cadmium chloride (base doses). After 24 h of exposure, cells and supernatants were harvested to examine cytotoxicity and genotoxicity of cadmium. The results show that both cell viability and concentration of testosterone excretion in primary Leydig cells are significantly lower in cadmium-exposed groups compared to the controls. Changes in testosterone excretion with human chorionic gonadotropin (hCG) stimulation is especially profound. The contents of malondialdehyde (MDA) and the activity of glutathione peroxidase (GSH-Px) in exposed groups are significantly higher than those in the control group, but the activity of superoxide dismutase (SOD) is lower. The number of cells with DNA single strand breaks and the levels of cellular DNA damage in all three exposure groups are significantly higher than in controls. These results indicate that cadmium is directly toxic to primary Leydig cells, and that the decreased percentage of normal cells and the increased level of DNA damage in cadmium-exposed Leydig cells may be responsible for decreased testosterone secretion. PMID:14555193

  17. Adrenomedullin attenuates interleukin-1β-induced inflammation and apoptosis in rat Leydig cells via inhibition of NF-κB signaling pathway.

    PubMed

    Hu, Wei; Zhou, Pang-hu; Rao, Ting; Zhang, Xiao-bin; Wang, Wei; Zhang, Li-jun

    2015-12-10

    The aim of this paper is to investigate the protective effects of adrenomedullin (ADM) on interleukin-1β (IL-1β)-induced inflammation and apoptosis in rat Leydig cells and its underlying molecular mechanisms. Leydig cells were isolated from adult Sprague-Dawley rats. The cell culture was established by adding ADM 2h prior to 24h treatment with IL-1β-induced cytotoxicity. We detected cell viability and concentrations of testosterone, reactive oxygen species (ROS), malondialdehyde (MDA), and reduced glutathione (GSH). Gene expression levels were measured for inducible nitric oxide synthase (iNOS) and cyclo-oxygenase-2 (COX-2). Concentrations were detected for nitric oxide (NO) and prostaglandin E2 (PGE2). Apoptosis was assessed using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Levels of gene expression and protein were detected for Bcl-2, Bax, caspase-3, and poly adenosine diphosphate-ribose polymerase (PARP). Protein levels were measured for nuclear factor kappa B (NF-κB) p65 and IκBα. ADM reduced IL-1β-induced cytotoxicity. ADM pretreatment significantly increased testosterone concentrations and decreased ROS, MDA, and GSH concentrations. ADM pretreatment inhibited IL-1β-induced inflammation in Leydig cells by decreasing the gene expression levels of iNOS and COX-2, as well as the concentrations of NO and PGE2. ADM pretreatment further decreased the number of TUNEL-positive stained Leydig cells, as confirmed by the increase in gene expression and protein levels of Bcl-2 and the decrease of Bax, caspase-3, and PARP levels. Moreover, ADM pretreatment inhibited NF-κB p65 phosphorylation and IκBα phosphorylation and degradation. ADM has potential anti-inflammatory and anti-apoptotic properties in IL-1β-induced rat Leydig cells, which might be related to NF-κB signaling pathway. PMID:26511504

  18. Mumps virus-induced innate immune responses in mouse Sertoli and Leydig cells

    PubMed Central

    Wu, Han; Shi, Lili; Wang, Qing; Cheng, Lijing; Zhao, Xiang; Chen, Qiaoyuan; Jiang, Qian; Feng, Min; Li, Qihan; Han, Daishu

    2016-01-01

    Mumps virus (MuV) infection frequently causes orchitis and impairs male fertility. However, the mechanisms underlying the innate immune responses to MuV infection in the testis have yet to be investigated. This study showed that MuV induced innate immune responses in mouse Sertoli and Leydig cells through TLR2 and retinoic acid-inducible gene I (RIG-I) signaling, which result in the production of proinflammatory cytokines and chemokines, including TNF-α, IL-6, MCP-1, CXCL10, and type 1 interferons (IFN-α and IFN-β). By contrast, MuV did not induce the cytokine production in male germ cells. In response to MuV infection, Sertoli cells produced higher levels of proinflammatory cytokines and chemokines but lower levels of type 1 IFNs than Leydig cells did. The MuV-induced cytokine production by Sertoli and Leydig cells was significantly reduced by the knockout of TLR2 or the knockdown of RIG-I signaling. The local injection of MuV into the testis triggered the testicular innate immune responses in vivo. Moreover, MuV infection suppressed testosterone synthesis by Leydig cells. This is the first study examining the innate immune responses to MuV infection in testicular cells. The results provide novel insights into the mechanisms underlying the MuV-induced innate immune responses in the testis. PMID:26776505

  19. Dehydroepiandrosterone inhibits cell proliferation and improves viability by regulating S phase and mitochondrial permeability in primary rat Leydig cells

    PubMed Central

    LIU, LIN; WANG, DIAN; LI, LONGLONG; DING, XIAO; MA, HAITIAN

    2016-01-01

    Dehydroepiandrosterone (DHEA) is widely used as a nutritional supplement and exhibits putative anti-aging properties. However, the molecular basis of the actions of DHEA, particularly on the biological characteristics of target cells, remain unclear. The aim of the current study was to investigate the effects of DHEA on cell viability, cell proliferation, cell cycle and mitochondrial function in primary rat Leydig cells. Adult Leydig cells were purified by Percoll gradient centrifugation, and cell proliferation was detected using a Click-iT® EdU Assay kit and cell cycle assessment performed using flow cytometry. Mitochondrial membrane potential was detected using JC-1 staining assay. The results of the current study demonstrate that DHEA decreased cell proliferation in a dose-dependent manner, whereas it improved cell viability in a time-dependent and dose-dependent manner. Flow cytometry analysis demonstrated that DHEA treatment increased the S phase cell population and decreased the G2/M cell population. Cyclin A and CDK2 mRNA levels were decreased in primary rat Leydig cells following DHEA treatment. DHEA treatment decreased the transmembrane electrical gradient in primary Leydig cells, whereas treatment significantly increased succinate dehydrogenase activity. These results indicated that DHEA inhibits primary rat Leydig cell proliferation by decreasing cyclin mRNA level, whereas it improves cells viability by modulating the permeability of the mitochondrial membrane and succinate dehydrogenase activity. These findings may demonstrate an important molecular mechanism by which DHEA activity is mediated. PMID:27220727

  20. Dehydroepiandrosterone inhibits cell proliferation and improves viability by regulating S phase and mitochondrial permeability in primary rat Leydig cells.

    PubMed

    Liu, Lin; Wang, Dian; Li, Longlong; Ding, Xiao; Ma, Haitian

    2016-07-01

    Dehydroepiandrosterone (DHEA) is widely used as a nutritional supplement and exhibits putative anti‑aging properties. However, the molecular basis of the actions of DHEA, particularly on the biological characteristics of target cells, remain unclear. The aim of the current study was to investigate the effects of DHEA on cell viability, cell proliferation, cell cycle and mitochondrial function in primary rat Leydig cells. Adult Leydig cells were purified by Percoll gradient centrifugation, and cell proliferation was detected using a Click-iT® EdU Assay kit and cell cycle assessment performed using flow cytometry. Mitochondrial membrane potential was detected using JC-1 staining assay. The results of the current study demonstrate that DHEA decreased cell proliferation in a dose‑dependent manner, whereas it improved cell viability in a time‑dependent and dose‑dependent manner. Flow cytometry analysis demonstrated that DHEA treatment increased the S phase cell population and decreased the G2/M cell population. Cyclin A and CDK2 mRNA levels were decreased in primary rat Leydig cells following DHEA treatment. DHEA treatment decreased the transmembrane electrical gradient in primary Leydig cells, whereas treatment significantly increased succinate dehydrogenase activity. These results indicated that DHEA inhibits primary rat Leydig cell proliferation by decreasing cyclin mRNA level, whereas it improves cells viability by modulating the permeability of the mitochondrial membrane and succinate dehydrogenase activity. These findings may demonstrate an important molecular mechanism by which DHEA activity is mediated. PMID:27220727

  1. Androgen-Forming Stem Leydig cells: Identification, Function and Therapeutic Potential

    PubMed Central

    Zhang, Yunhui; Ge, Renshan; Hardy, Matthew P.

    2008-01-01

    Leydig cells are the primary source of testosterone in the male, and differentiation of Leydig cells in the testes is one of the primary events in the development of the male body and fertility. Stem Leydig cells (SLCs) exist in the testis throughout postnatal life, but a lack of cell surface markers previously hindered attempts to obtain purified SLC fractions. Once isolated, the properties of SLCs provide interesting clues for the ontogeny of these cells within the embryo. Moreover, the clinical potential of SLCs might be used to reverse age-related declines in testosterone levels in aging men, and stimulate reproductive function in hypogonadal males. This review focuses on the source, identification and outlook for therapeutic applications of SLCs. Separate pools of SLCs may give rise to fetal and adult generations of Leydig cell, which may account for their observed functional differences. These differences should in turn be taken into account when assessing the consequences of environmental pollutants such as the phthalate ester, diethylhexylphthalate (DEHP). PMID:18525122

  2. cAMP-Specific Phosphodiesterases 8A and 8B, Essential Regulators of Leydig Cell Steroidogenesis

    PubMed Central

    Shimizu-Albergine, Masami; Tsai, Li-Chun Lisa; Patrucco, Enrico

    2012-01-01

    Phosphodiesterase (PDE) 8A and PDE8B are high-affinity, cAMP-specific phosphodiesterases that are highly expressed in Leydig cells. PDE8A is largely associated with mitochondria, whereas PDE8B is broadly distributed in the cytosol. We used a new, PDE8-selective inhibitor, PF-04957325, and genetically ablated PDE8A(−/−), PDE8B(−/−) and PDE8A(−/−)/B(−/−) mice to determine roles for these PDEs in the regulation of testosterone production. PF-04957325 treatment of WT Leydig cells or MA10 cells increased steroid production but had no effect in PDE8A (−/−)/B(−/−) double-knockout cells, confirming the selectivity of the drug. Moreover, under basal conditions, cotreatment with PF-04957325 plus rolipram, a PDE4-selective inhibitor, synergistically potentiated steroid production. These results suggest that the pool(s) of cAMP regulating androgen production are controlled by PDE8s working in conjunction with PDE4. Likewise, PDE8A (−/−)/B(−/−) cells had higher testosterone production than cells from either PDE8A(−/−) or PDE8B(−/−) mice, suggesting that both PDE8s work in concert to regulate steroid production. We further demonstrate that combined inhibition of PDE8s and PDE4 greatly increased PKA activity including phosphorylation of cholesterol-ester hydrolase (CEH)/hormone-sensitive lipase (HSL). CEH/HSL phosphorylation also was increased in PDE8A(−/−)/B(−/−) cells compared with WT cells. Finally, combined inhibition of PDE8s and PDE4 increased the expression of steroidogenic acute regulatory (StAR) protein. Together these findings suggest that both PDE8A and PDE8B play essential roles to maintain low cAMP levels, thereby suppressing resting steroidogenesis by keeping CEH/HSL inactive and StAR protein expression low. They also suggest that in order for PDE inhibitor therapy to be an effective stimulator of steroidogenesis, both PDE8 isozymes and PDE4 need to be simultaneously targeted. PMID:22232524

  3. Modulation of mouse Leydig cell steroidogenesis through a specific arginine-vasopressin receptor

    SciTech Connect

    Tahri-Joutei, A.; Pointis, G.

    1988-01-01

    Characterization of specific vasopressin binding sites was investigated in purified mouse Leydig cells using tritiated arginine-vasopressin. Binding of radioligand was saturable, time- and temperature-dependent and reversible. (/sup 3/H)-AVP was found to bind to a single class of sites with high affinity and low capacity. Binding displacements with specific selection analogs of AVP indicated the presence of V/sub 1/ subtype receptors on Leydig cells. The ability of AVP to displace (/sup 3/H)-AVP binding was greater than LVP and oxytocin. The unrelated peptides, somatostatin and substance P, were less potent, while neurotensin and LHRH did not displace (/sup 3/H)-AVP binding. The time-course effects of AVP-pretreatment on basal and hCG-stimulated testosterone and cAMP accumulations were studied in primary culture of Leydig cells. Basal testosterone accumulation was significantly increased by a 24 h AVP-pretreatment of Leydig cells. This effect was potentiated by the phosphodiesterase inhibitor (MIX) and was concomitantly accompanied by a slight but significant increase in cAMP accumulation. AVP-pretreatment of the cells for 72 h had no effect on basal testosterone accumulation, but exerted a marked inhibitory effect on the hCG-stimulated testosterone accumulation. This reduction of testosterone accumulation occurred even in the presence of MIX and was not accompanied by any significant change of cAMP levels.

  4. BLTK1 murine Leydig cells: a novel steroidogenic model for evaluating the effects of reproductive and developmental toxicants.

    PubMed

    Forgacs, Agnes L; Ding, Qi; Jaremba, Rosemary G; Huhtaniemi, Ilpo T; Rahman, Nafis A; Zacharewski, Timothy R

    2012-06-01

    Leydig cells are the primary site of androgen biosynthesis in males. Several environmental toxicants target steroidogenesis resulting in both developmental and reproductive effects including testicular dysgenesis syndrome. The aim of this study was to evaluate the effect of several structurally diverse endocrine disrupting compounds (EDCs) on steroidogenesis in a novel BLTK1 murine Leydig cell model. We demonstrate that BLTK1 cells possess a fully functional steroidogenic pathway that produces low basal levels of testosterone (T) and express all the necessary steroidogenic enzymes including Star, Cyp11a1, Cyp17a1, Hsd3b1, Hsd17b3, and Srd5a1. Recombinant human chorionic gonadotropin (rhCG) and forskolin (FSK) elicited concentration- and time-dependent induction of 3',5'-cyclic adenosine monophosphate, progesterone (P), and T, as well as the differential expression of Star, Hsd3b6, Hsd17b3, and Srd5a1 messenger RNA levels. The evaluation of several structurally diverse male reproductive toxicants including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), atrazine, prochloraz, triclosan, monoethylhexyl phthalate (MEHP), glyphosate, and RDX in BLTK1 cells suggests different modes of action perturb steroidogenesis. For example, prochloraz and triclosan antifungals reduced rhCG induction of T, consistent with published in vivo data but did not alter basal T levels. In contrast, atrazine and MEHP elicited modest induction of basal T but antagonized rhCG-mediated induction of T levels, whereas TCDD, glyphosate, and RDX had no effect on basal or rhCG induction of T in BLTK1 cells. These results suggest that BLTK1 cells maintain rhCG-inducible steroidogenesis and are a viable in vitro Leydig cell model to evaluate the effects of EDCs on steroidogenesis. This model can also be used to elucidate the different mechanisms underlying toxicant-mediated disruption of steroidogenesis. PMID:22461451

  5. Mutational analysis of the luteinizing hormone receptor gene in two individuals with Leydig cell tumors.

    PubMed

    Canto, Patricia; Söderlund, Daniela; Ramón, Guillermo; Nishimura, Elisa; Méndez, Juan Pablo

    2002-03-01

    Inactivating mutations of the luteinizing hormone receptor (LHR) gene in males induce Leydig cell agenesis or hypoplasia, while activating mutations cause testotoxicosis. Recently, it was demonstrated that a somatic heterozygous activating mutation of the LHR gene (Asp578His), limited to the tumor, was the cause of Leydig cell adenomas in three unrelated patients. We describe the molecular study of two unrelated boys with gonadotropin-independent hypersecretion of testosterone due to Leydig cell adenomas. Genomic DNA was extracted from the tumor, the adjacent normal testis tissue, and blood leukocytes. Both individuals exhibited an heterozygous missense mutation, limited only to the tumor, consisting of a guanine (G) to cytosine (C) substitution at codon 578 (GAT to CAT), turning aspartic acid into histidine. The presence of the same mutation in different ethnic groups demonstrates the existence of a mutational hot spot in the LHR gene. Indeed, this mutation occurs at the conserved aspartic acid residue at amino acid 578, where a substitution by glycine is the most common mutation observed in testotoxicosis and where a substitution by tyrosine has been linked to a more severe clinical phenotype where diffuse Leydig cell hyperplasia is found. Our results confirm the fact that somatic activating mutations of gonadotropin receptors are involved in gonadal tumorigenesis. PMID:11857565

  6. EFFECT OF CADMIUM AND OTHER METAL CATIONS ON IN VITRO LEYDIG CELL TESTOSTERONE PRODUCTION

    EPA Science Inventory

    In vivo assessment of toxicant action on Leydig cell function is subject to homeostatic mechanisms which make it difficult to determine whether any changes seen in serum testosterone (T) concentration are due to extragonadal endocrine alternations or to a direct effect on the Ley...

  7. MODULATION OF RAT LEYDIG CELL STEROIDOGENIC FUNCTION BY DI(2-ETHYLHEXYL)PHTHALATE

    EPA Science Inventory

    Modulation of rat Leydig cell steroidogenic function by di(2-ethylhexyl)phthalate.

    Akingbemi BT, Youker RT, Sottas CM, Ge R, Katz E, Klinefelter GR, Zirkin BR, Hardy MP.

    Center for Biomedical Research, Population Council, New York, New York 10021, USA. benson@popcbr...

  8. IN VITRO/IN VIVO EFFECTS OF ETHANE DIMETHANESULPHONATE ON LEYDIG CELLS OF ADULT RATS

    EPA Science Inventory

    Ethane dimethanesulphonate (EDS) is studied extensively to date, certain toxicological criteria have not been met. or instance, the does-responsiveness of Leydig cells to EDS, both in vitro and in vivo, is not well established. n addition, the date regarding the cellular site of ...

  9. True Precocious Puberty Following Treatment of a Leydig Cell Tumor: Two Case Reports and Literature Review

    PubMed Central

    Verrotti, Alberto; Penta, Laura; Zenzeri, Letizia; Lucchetti, Laura; Giovenali, Paolo; De Feo, Pierpaolo

    2015-01-01

    Leydig cell testicular tumors are a rare cause of precocious pseudopuberty in boys. Surgery is the main therapy and shows good overall prognosis. The physical signs of precocious puberty are expected to disappear shortly after surgical removal of the mass. We report two children, 7.5 and 7.7 year-old boys, who underwent testis-sparing surgery for a Leydig cell testicular tumor causing precocious pseudopuberty. During follow-up, after an immediate clinical and laboratory regression, both boys presented signs of precocious puberty and ultimately developed central precocious puberty. They were successfully treated with gonadotropin-releasing hormone (GnRH) analogs. Only six other cases have been described regarding the development of central precocious puberty after successful treatment of a Leydig cell tumor causing precocious pseudopuberty. Gonadotropin-dependent precocious puberty should be considered in children treated for a Leydig cell tumor presenting persistent or recurrent physical signs of puberty activation. In such cases, therapy with GnRH analogs appears to be the most effective medical treatment. PMID:26579503

  10. Insulin-like growth factor-I (IGF-I) protects cultured equine Leydig cells from undergoing apoptosis.

    PubMed

    Yoon, M J; Roser, J F

    2010-12-01

    Leydig cells located in the interstitial space of the testicular parenchyma produce testosterone which plays a critical role in the maintenance and restoration of spermatogenesis in many species, including horses. For normal spermatogenesis, maintaining Leydig cells is critical to provide an optimal and constant level of testosterone. Recently, an anti-apoptotic effect of IGF-I in testicular cells in rats has been reported, but a similar effect of IGF-I on equine Leydig cells remains to be elucidated. If IGF-I also protects stallion testicular cells from undergoing apoptosis, then IGF-I may have potential as a treatment regime to prevent testicular degeneration. The present study was designed to evaluate the anti-apoptotic effect of IGF-I on cultured equine Leydig cells. Testes were collected from 5 post-pubertal stallions (2-4 years old) during routine castrations. A highly purified preparation of equine Leydig cells was obtained from a discontinuous Percoll gradient. Purity of equine Leydig cells was assessed using histochemical 3β-HSD staining. Equine Leydig cells and selected doses of recombinant human IGF-1 (rhIGF-I; Parlow A.F., National Hormone and Peptide Program, Harbor-UCLA Medical Center) were added to wells of 24 or 96 well culture plates in triplicate and cultured for 24 or 48 h under 95% air:5% CO(2) at 34°C. After 24 or 48 h incubation, apoptotic rate was assessed using a Cell Death Detection ELISA kit. Significantly lower apoptotic rates were observed in equine Leydig cells cultured with 5, 10, or 50ng/ml of rhIGF-I compared with control cells cultured without rhIGF-I for 24h. Exposure to 1, 5, 10 or 50 ng/ml of rhIGF-I significantly decreased apoptotic rate in equine Leydig cells cultured for 48 h. After 48 h incubation, cells were labeled with Annexin V and propodium iodine to determine the populations of healthy, apoptotic, and necrotic cells by counting stained cells using a Nikon Eclipse inverted fluorescence microscope. As a percentage of

  11. Growth suppression of Leydig TM3 cells mediated by aryl hydrocarbon receptor

    SciTech Connect

    Iseki, Minoru; Ikuta, Togo; Kobayashi, Tetsuya; Kawajiri, Kaname . E-mail: kawajiri@cancer-c.pref.saitama.jp

    2005-06-17

    Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin induces developmental toxicity in reproductive organs. To elucidate the function of AhR, we generated stable transformants of TM3 cells overexpressing wild-type aryl hydrocarbon receptor (AhR) or its mutants which carried mutations in nuclear localization signal or nuclear export signal. In the presence of 3-methylcholanthrene (MC), proliferation of the cells transfected with wild-type AhR was completely suppressed, whereas cells expressing AhR mutants proliferated in a manner equivalent to control TM3 cells, suggesting AhR-dependent growth inhibition. The suppression was associated with up-regulation of cyclin-dependent kinase inhibitor p21{sup Cip1}, which was abolished by pretreatment with actinomycin D. A p38 MAPK specific inhibitor, SB203580, blocked the increase of p21{sup Cip1} mRNA in response to MC. Treatment with indigo, another AhR ligand, failed to increase of p21{sup Cip1} mRNA, although up-regulation of mRNA for CYP1A1 was observed. These data suggest AhR in Leydig cells mediates growth inhibition by inducing p21{sup Cip1}.

  12. Midazolam regulated caspase pathway, endoplasmic reticulum stress, autophagy, and cell cycle to induce apoptosis in MA-10 mouse Leydig tumor cells

    PubMed Central

    So, Edmund Cheung; Chen, Yung-Chia; Wang, Shu-Chun; Wu, Chia-Ching; Huang, Man-Chi; Lai, Meng-Shao; Pan, Bo-Syong; Kang, Fu-Chi; Huang, Bu-Miin

    2016-01-01

    Purpose Midazolam is widely used as a sedative and anesthetic induction agent by modulating the different GABA receptors in the central nervous system. Studies have also shown that midazolam has an anticancer effect on various tumors. In a previous study, we found that midazolam could induce MA-10 mouse Leydig tumor cell apoptosis by activating caspase cascade. However, the detailed mechanism related to the upstream and downstream pathways of the caspase cascade, such as endoplasmic reticulum (ER) stress, autophagy, and p53 pathways plus cell cycle regulation in MA-10 mouse Leydig tumor cells, remains elusive. Methods Flow cytometry assay and Western blot analyses were exploited. Results Midazolam significantly decreased cell viability but increased sub-G1 phase cell numbers in MA-10 cells (P<0.05). Annexin V/propidium iodide double staining further confirmed that midazolam induced apoptosis. In addition, expressions of Fas and Fas ligand could be detected in MA-10 cells with midazolam treatments, and Bax translocation and cytochrome c release were also involved in midazolam-induced MA-10 cell apoptosis. Moreover, the staining and expression of LC3-II proteins could be observed with midazolam treatment, implying midazolam could induce autophagy to control MA-10 cell apoptosis. Furthermore, the expressions of p-EIF2α, ATF4, ATF3, and CHOP could be induced by midazolam, indicating that midazolam could stimulate apoptosis through ER stress in MA-10 cells. Additionally, the expressions of cyclin A, cyclin B, and CDK1 could be inhibited by midazolam, and the phosphorylation of p53, P27, and P21 could be adjusted by midazolam, suggesting that midazolam could manage cell cycle through the regulation of p53 pathway to induce apoptosis in MA-10 cells. Conclusion Midazolam could induce cell apoptosis through the activation of ER stress and the regulation of cell cycle through p53 pathway with the involvement of autophagy in MA-10 mouse Leydig tumor cells. PMID:27175086

  13. Large moderately-differentiated ovarian Sertoli-Leydig cell tumor in a 13-year-old female: A case report

    PubMed Central

    ZHANG, HUI; HAO, JING; LI, CHUN-YAN; LI, TAO; MU, YU-LAN

    2016-01-01

    Sertoli-Leydig cell tumor of the ovary, also known as androblastoma, is a rare neoplasm from the group of sex cord-stromal tumors of the ovary. The tumor accounts for <0.5% of all primary ovarian neoplasms. The clinical signs and symptoms of Sertoli-Leydig cell tumors can be associated with either hormonal production or the presence of a mass-occupying lesion. In the current study, a 13-year-old female was diagnosed with a stage Ic ovarian Sertoli-Leydig cell tumor following abdominal pain and distension. One month after a right oophorectomy, the follow-up magnetic resonance imaging scan was negative for residual or recurrent tumor. The overall 5-year survival rate for moderately-differentiated (grade 2) and poorly-differentiated (grade 3) Sertoli-Leydig cell tumors is 80%, and long-term follow-up is therefore highly advised in this patient. PMID:26893701

  14. T-2 toxin-induced cytotoxicity and damage on TM3 Leydig cells.

    PubMed

    Yuan, Zhihang; Matias, Froilan Bernard; Yi, Jin-E; Wu, Jing

    2016-01-01

    T-2 toxin is a highly toxic mycotoxin produced by various Fusarium species, mainly, Fusarium sporotrichoides, and has been reported to have toxic effects on reproductive system of adult male animals. This study investigated the dose-dependent cytotoxicity of T-2 toxin on reproductive cells using TM3 Leydig cells. Specifically, the cytotoxic effect of T-2 toxin was assessed by measuring cell viability; lactate dehydrogenase (LDH); malondialdehyde (MDA); antioxidant activity by measuring superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), and DNA damage; and cell apoptosis. Results showed that T-2 toxin is highly cytotoxic on TM3 Leydig cells. However, Trolox-treated TM3 Leydig cells showed significantly reduced oxidative damage, DNA damage, and apoptosis induced by T-2 toxin. This study proves that T-2 toxin can damage the testes and thus affects the reproductive capacity of animals and humans. Furthermore, oxidative stress plays an important role in the cytotoxic effect of T-2 toxin. PMID:26707243

  15. Covalent affinity labeling, radioautography, and immunocytochemistry localize the glucocorticoid receptor in rat testicular Leydig cells

    SciTech Connect

    Stalker, A.; Hermo, L.; Antakly, T. )

    1989-12-01

    The presence and distribution of glucocorticoid receptors in the rat testis were examined by using 2 approaches: in vivo quantitative radioautography and immunocytochemistry. Radioautographic localization was made possible through the availability of a glucocorticoid receptor affinity label, dexamethasone 21-mesylate, which binds covalently to the glucocorticoid receptor, thereby preventing dissociation of the steroid-receptor complex. Adrenalectomized adult rats were injected with a tritiated (3H) form of this steroid into the testis and the tissue was processed for light-microscope radioautography. Silver grains were observed primarily over the Leydig cells of the interstitial space and to a lesser extent, over the cellular layers which make up the seminiferous epithelium, with no one cell type showing preferential labeling. To determine the specificity of the labeling, a 25- or 50-fold excess of unlabeled dexamethasone was injected simultaneously with the same dose of (3H)-dexamethasone 21-mesylate. In these control experiments, a marked reduction in label intensity was noted over the Leydig as well as tubular cells. Endocytic macrophages of the interstitium were non-specifically labeled, indicating uptake of the ligand possibly by fluid-phase endocytosis. A quantitative analysis of the label confirmed the presence of statistically significant numbers of specific binding sites for glucocorticoids in both Leydig cells and the cellular layers of the seminiferous epithelium; 86% of the label was found over Leydig cells, and only 14% over the cells of the seminiferous epithelium. These binding data were confirmed by light-microscope immunocytochemistry using a monoclonal antibody to the glucocorticoid receptor.

  16. Sub-acute intravenous administration of silver nanoparticles in male mice alters Leydig cell function and testosterone levels

    PubMed Central

    GARCIA, THOMAS X.; COSTA, GUILHERME M. J.; FRANÇA, LUIZ R.; HOFMANN, MARIE-CLAUDE

    2014-01-01

    The aim of this study was to determine whether short-term, in vivo exposure to silver nanoparticles (AgNPs) could be toxic to male reproduction. Low dose (1 mg/kg/dose) AgNPs were intravenously injected into male CD1 mice over 12 days. Treatment resulted in no changes in body and testis weights, sperm concentration and motility, fertility indices, or follicle-stimulating hormone and luteinizing hormone serum concentrations; however, serum and intratesticular testosterone concentrations were significantly increased 15 days after initial treatment. Histologic evaluation revealed significant changes in epithelium morphology, germ cell apoptosis, and Leydig cell size. Additionally, gene expression analysis revealed Cyp11a1 and Hsd3b1 mRNA significantly upregulated in treated animals. These data suggest that AgNPs do not impair spermatogonial stem cells in vivo since treatment did not result in significant decreases in testis weight and sperm concentrations. However, AgNPs appear to affect Leydig cell function, yielding increasing testicular and serum testosterone levels. PMID:24447867

  17. A METABOLITE OF METHOXYCHLOR,2,2-BIS(P-HYDOXYPHENYL)-1,1,1- TRICHLOROETHANE REDUCES TESTOSTERONE BIOSYNTHESIS IN RAT LEYDIG CELLS THROUGH SUPPRESSION OF STEADY-STATE MESSENGER RIBONUCLEIC ACID LEVELS OF THE CHOLESTEROL SIDE-CHAIN CLEAVAGE ENZYME

    EPA Science Inventory

    Postnatal development of Leydig cells involves transformation through three stages: progenitor, immature, and adult Leydig cells. The process of differentiation is accompanied by a progressive increase in the capacity of Leydig cells to produce testosterone (T). T promotes the ma...

  18. Immunofluorescent localization of the StAR protein in mitochondria of mouse Leydig cells in vitro.

    PubMed

    Kotula, M; Kozieł, E; Sadowska, J; Gancarczyk, M; Bilińska, B

    2001-01-01

    The Steroidogenic Acute Regulatory (StAR) protein is assumed to enhance the rate-limiting step of the steroid biosynthesis. Now, it is the most likely candidate, responsible for acutely regulating transfer of cholesterol from the outer to the inner mitochondrial membrane. In this study, the immunoreactive StAR protein was observed in the mitochondria of mouse cultured Leydig cells stimulated by hCG andtesticular macrophage-conditioned medium. Immunocytochemistry was performed using a polyclonal rabbit antibody against the StAR protein. For selective staining of mitochondria in Leydig cells, the Mito Tracker dye was used. Computerized, superimposed images from double-fluorescence staining showed a remarkable degree of similarity in the distribution of the StAR protein and mitochondria, indicating mitochondrial localization of StAR. PMID:11374809

  19. Leydig-cell function in children after direct testicular irradiation for acute lymphoblastic leukemia

    SciTech Connect

    Brauner, R.; Czernichow, P.; Cramer, P.; Schaison, G.; Rappaport, R.

    1983-07-07

    To assess the effect of testicular irradiation on testicular endocrine function, we studied 12 boys with acute lymphoblastic leukemia who had been treated with direct testicular irradiation 10 months to 8 1/2 years earlier. Insufficient Leydig-cell function, manifested by a low response of plasma testosterone to chorionic gonadotropin or an increased basal level of plasma luteinizing hormone (or both), was observed in 10 patients, 7 of whom were pubertal. Two of these patients had a compensated testicular endocrine insufficiency with only high plasma concentrations of luteinizing hormone. Testosterone secretion was severely impaired in three pubertal boys studied more than four years after testicular irradiation. A diminished testicular volume indicating tubular atrophy was found in all pubertal patients, including three who had not received cyclophosphamide or cytarabine. These data indicate that testosterone insufficiency is a frequent complication of testicular irradiation, although some patients continue to have Leydig-cell activity for several years after therapy.

  20. Steroid metabolism by purified adult rat Leydig cells in primary culture

    SciTech Connect

    Browning, J.Y.; Tcholakian, R.K.; Kessler, M.J.; Grotjan, H.E. Jr.

    1982-11-01

    To characterize Leydig cell steroidogensis, we examined the metabolism of (3H)pregnenolone (3 beta-hydroxy-5-pregnen-20-one) to androgens in the presence and absence of human chorionic gonadotropin (hCG) as a function of culture duration. Approximately 20-30% of the (3H)pregnenolone was converted to testosterone (17 beta-hydroxy-4-androsten-3-one) by purified Leydig cells at 0, 3 and 5 days (d) of culture. Androstenedione (4-androstene-3,17-dione) and dihydrotestosterone (17 beta-hydroxy-5 alpha-androstan-3-one) were also produced while on day 5 of culture, significant amounts of progesterone (4-pregnene-3,20-dione) were isolated. The delta 5 intermediates, 17-hydroxypregnenolone (3 beta, 17-dihydroxy-5-pregnen-20-one) and dehydroepiandrosterone (3 beta-hydroxy-5-androsten-17-one), accounted for less than 1% of substrate conversion, indicating a clear preference for Leydig cells to metabolize (3H)pregnenolone via the delta 4 pathway. On day 0 of culture, unidentified metabolites considered of predominately polar steroids while on day 5 of culture, the unidentified metabolites consisted of predominately nonpolar steroids. In the presence of hCG, (3H-pregnenolone metabolism did not differ from basal on day 0 or 3 of culture. HCG increased the conversion of pregnenolone to progesterone and 17-hydroxyprogesterone (17-hydroxy-4-pregnene-3,20-dione) on 5d. This suggests that Leydig cells cultured for 5d have decreased C17-20 desmolase activity or that hCG acutely stimulates 3 beta-hydroxysteroid dehydrogenase and delta 5-delta 5 isomerase activities.

  1. Zinc-induced survival of Leydig cells in Fischer rats (Rattus norvegicus) treated with cadmium chloride.

    PubMed

    Villanueva, Octavio; Vigueras, Rosa María; Hernández, Rafael; Chavira, Roberto; Cárdenas, Mario; Villa, Antonio; Murphy, Eduardo

    2005-12-01

    Zinc is known to prevent cadmium-induced carcinogenesis and Leydig cell destruction in rat testes; however, the mechanism of action is not known, although it has been suggested that pituitary feedback increases the production of luteinizing hormone (LH) in response to low circulating androgen. We therefore examined the biological role of zinc in reducing cadmium toxicity in the Leydig cells of Fischer rats. Two groups of eleven 6-month-old rats were injected subcutaneously with 20 micromol CdCl2/kg weekly for 5 weeks; one of these groups also received 1 mmol/kg zinc acetate weekly for the same 5 weeks. A third group of rats received 1 mmol/kg zinc acetate weekly, and a fourth group was injected with saline weekly for 5 weeks. After 8 months of study, the animals were euthanized by CO2 inhalation. The results indicated that the number of surviving Leydig cells was significantly lower in the cadmium group (7.34% = 0.095 x 10(9)/cm3) than in the cadmium-zinc group (20.85%) or control animals (91.2%). Moreover, the concentrations of serum testosterone and LH were significantly higher in the cadmium group than in any of the other groups. This difference probably was due to the testosterone produced by a small reservoir of surviving Leydig cells and to other endocrine factors. These findings suggest that Fischer rat testis may be a good model system for testing the effects of cadmium and zinc on the production of LH and testosterone and other androgens before spontaneous cancers develop. PMID:16422150

  2. PURIFICATION OF RAT LEYDIG CELLS: INCREASED YIELDS AFTER UNIT-GRAVITY SEDIMENTATION OF COLLAGENASE-DISPERSED INTERSTITIAL CELLS

    EPA Science Inventory

    Abstract

    Procedures for purification of Leydig cells have facilitated studies of their regulatory biology. A multistep procedure, that includes a filtration with nylon mesh (100 micron pore size) to separate interstitial cells from the seminiferous tubules, combining centr...

  3. Endocrine regulation of testosterone production by Leydig cells in the catfish, Clarias batrachus: probable mediators of growth hormone.

    PubMed

    Nee Pathak, N Dubey; Kumar, Pankaj; Lal, Bechan

    2015-03-01

    Growth hormone (GH), in the recent past, has been recognized as a potent steroid stimulating hormone independent of gonadotropin (GtH). However, the mode and mechanism of its steroidogenic action in the testis is not yet elucidated, particularly in fish. The present study was designed to understand the mode and mechanism of steroidogenic action of growth hormone in testis of the catfish, Clarias batrachus through in vivo and in vitro Leydig cell culture studies using the signaling molecule inhibitors. Exogenous administration of GtH, GH and insulin to the male catfish increased testicular and circulating testosterone level. In vitro treatment of Leydig cells with these hormones also increased testosterone production. The steroidogenic action of GH appeared to be indirect and mediated through Leydig cell produced insulin-like growth factor I (IGF-I), as the treatments with actinomycin D, cycloheximide and anti-IGF-I abolished the GH-induced testosterone production by Leydig cells. The GH-induced stimulation in IGF-I production by the isolated Leydig cells further substantiates this notion. GH appears to employ cAMP/PKA and tyrosine kinase signaling pathways to induce IGF-I production, as the adenylyl cyclase inhibitor (SQ 22,536), cAMP-dependent protein kinase (PKA) blocker (H-89) and tyrosine kinase inhibitor (lavendustin A) abolished the GH-induced IGF-I production and in turn testosterone by the Leydig cells. This study suggests that GH exerts independent androgenic effect in the catfish testis indirectly through augmenting the Leydig cell production of IGF-I. PMID:25650168

  4. Long duration exposure to cadmium leads to increased cell survival, decreased DNA repair capacity, and genomic instability in mouse testicular Leydig cells.

    PubMed

    Singh, Kamaleshwar P; Kumari, Ragini; Pevey, Christina; Jackson, Desiree; DuMond, James W

    2009-06-28

    Epidemiological and experimental studies have shown that cadmium is carcinogenic to human and experimental animals, however, the mechanism of cadmium-induced carcinogenesis is not clear. The aberrant expression of cell cycle and DNA repair genes resulting in increased cell proliferation and genomic instability are the characteristic features of cancer cells. The purpose of this study was to determine if exposure to cadmium can perturb cell proliferation/survival and causes genomic instability in TM3 cells, a mouse testicular Leydig cell line. The results of this study revealed that short-duration exposure to lower doses of cadmium significantly increase the growth of TM3 cells, whereas, higher doses are toxic and cause cell death. The long duration exposure to higher doses of cadmium, however, results in increased cell survival and acquisition of apoptotic resistance. Gene expression analysis by real-time PCR revealed increased expression of the anti-apoptotic gene Bcl-2, whereas decreased expression of pro-apoptotic gene Bax. Decreased expression of genes for maintenance of DNA methylation, DNMT1, and DNA repair, OGG1 and MYH, was also observed in cells exposed to cadmium for 24h. The random amplified polymorphic DNA (RAPD) assay revealed genomic instability in cells with chronic exposure to cadmium. The findings of this study indicate that mouse testicular Leydig cells adapt to chronic cadmium exposure by increasing cell survival through increased expression of Bcl-2, and decreased expression of Bax. The increased proliferation of cells with genomic instability may result in malignant transformation, and therefore, could be a viable mechanism for cadmium-induced cancers. PMID:19232459

  5. Sustained in vivo blockade of α₁-adrenergic receptors prevented some of stress-triggered effects on steroidogenic machinery in Leydig cells.

    PubMed

    Stojkov, Natasa J; Janjic, Marija M; Baburski, Aleksandar Z; Mihajlovic, Aleksandar I; Drljaca, Dragana M; Sokanovic, Srdjan J; Bjelic, Maja M; Kostic, Tatjana S; Andric, Silvana A

    2013-07-15

    This study was designed to systematically analyze and evaluate the effects of in vivo blockade of α₁-adrenergic receptors (α₁-ADRs) on the stress-induced disturbance of steroidogenic machinery in Leydig cells. Parameters followed 1) steroidogenic enzymes/proteins, transcription factors, and cAMP/testosterone production; 2) the main hallmarks of stress (epinephrine, glucocorticoids); and 3) transcription profiles of ADRs and oxidases with high affinity to inactivate glucocorticoids. Results showed that sustained blockade of α₁-ADRs prevented stress-induced 1) decrease of the transcripts/proteins for main steroidogenic CYPs (CYP11A1, CYP17A1); 2) decrease of Scarb1 and Hsd3b1 transcripts; 3) decrease of transcript for Nur77, one of the main activator of the steroidogenic expression; and 4) increase of Dax1 and Arr19, the main steroidogenic repressors in Leydig cells. In the same cells, the expression of steroidogenic stimulatory factor Creb1, StAR, and androgen receptor increased. In this signaling scenario, stress-induced stimulation of Adra1a/Adra1b/Adrbk1 and Hsd11b2 (the unidirectional oxidase with high affinity to inactivate glucocorticoids) was not changed. Blockade additionally stimulated stress-increased transcription of the most abundantly expressed ADRs Adra1d/Adrb1/Adrb2 in Leydig cells. In the same cells, stress-decreased testosterone production, the main marker of Leydig cells functionality, was completely prevented, while reduction of cAMP, the main regulator of androgenesis, was partially prevented. Accordingly, the presented data provide a new molecular/transcriptional base for "fight/adaptation" of steroidogenic cells and new molecular insights into the role of α₁-ADRs in stress-impaired Leydig cell steroidogenesis. The results are important in term of wide use of α₁-ADR selective antagonists, alone/in combination, to treat high blood pressure, nightmares associated with posttraumatic stress disorder, and disrupted sexual health. PMID

  6. Characterization of rat leydig cell gonadotropin receptor structure by affinity cross-linking

    SciTech Connect

    Zhang, Q.Y.; Hwang, J.; Menon, K.M.J.

    1986-05-01

    The gonadotropin receptor from rat leydig cell has been characterized with respect to binding kinetics and physiological regulation. The present study was intended to examine the structure of the receptor. Leydig cell suspension was prepared by either collagenase digestion or by mechanical disruption of the testis. The cells were incubated with /sup 125/I-hCG and the unreacted hCG was removed by centrifugation. The /sup 125/I-hCG was then covalently linked to the cell surface receptor using cleavable (dithiobis (succinimidyl propionate)) and non-cleavable (disuccinimidyl suberate) cross-linking reagents. The extracted cross-linked membrane proteins were resolved on SDS-polyacrylamide gels under reducing and non-reducing conditions and subjected to autoradiographic analysis. Under non-reducing conditions, two labeled species with M/sub r/ = 87,000 and 120,000 were detected. However, only one labeled band was detected under reducing conditions with M/sub r/ = 64,000. The binding of /sup 125/I-hCG to the receptor was inhibited by hCG and LH, but not by a number of peptides and proteins. The data suggest that hCG receptor in leydig cell is an oligomeric complex consisting of four subunits, ..cap alpha cap alpha beta gamma... The ..beta.. and ..gamma.. subunits are each linked to an ..cap alpha.. subunit through disulfide linkage and the hormone binds to each ..cap alpha.. subunit. The two dimers formed (..cap alpha beta cap alpha gamma..) are associated by noncovalent interactions.

  7. DICER1 mutations in Familial Multi-Nodular Goiter with and without Ovarian Sertoli-Leydig Cell Tumors

    PubMed Central

    Frio, Thomas Rio; Bahubeshi, Amin; Kanellopoulou, Chryssa; Hamel, Nancy; Niedziela, Marek; Sabbaghian, Nelly; Pouchet, Carly; Gilbert, Lucy; O’Brien, Paul K.; Serfas, Kim; Broderick, Peter; Houlston, Richard S.; Lesueur, Fabienne; Bonora, Elena; Muljo, Stefan; Schimke, R. Neil; Soglio, Dorothée Bouron-Dal; Arseneau, Jocelyne; Schultz, Kris Ann; Priest, John R.; Nguyen, Van-Hung; Harach, H. Ruben; Livingston, David M.; Foulkes, William D.; Tischkowitz, Marc

    2012-01-01

    Context Non-toxic multinodular goiter (MNG) is frequently observed in the general population, but little is known about the underlying genetic susceptibility to this disease. Familial cases of MNG have been reported and there are five such published families which also contain individuals with Sertoli-Leydig cell tumors of the ovary (SLCT). Germline mutations in DICER1, a gene that codes for an RNase III endoribonuclease, have recently been identified in families affected pleuropulmonary blastoma (PPB), some of whom include cases of MNG and gonadal tumors such as SLCT. Objective To determine whether familial MNG with or without SLCT in the absence of PPB was caused by mutations in DICER1. Design, Setting and Patients From September 2009 to September 2010, we studied two MNG families and three MNG/SLCT families. We screened affected probands for mutations in the DICER1 gene. We investigated blood lymphocytes, MNG and SLCT tissue from family members for loss of the wild-type allele (loss of heterozygosity), DICER1 expression and microRNA dysregulation. Main Outcome Measure(s) Detection of germline DICER1 gene mutations in familial MNG with and without SLCT. Results We identified and characterized germline DICER1 mutations in all five families. Molecular analysis of the three SLCTs showed no loss of heterozygosity at DICER1, and IHC analysis in two available samples showed strong expression of DICER1 in Sertoli cells, but weak staining of Leydig cells. MicroRNA profiling of RNA derived from lymphoblastoid cell lines from both affected and unaffected members of the familial MNG cases revealed miRNA perturbations in DICER1 mutation carriers. Conclusions DICER1 mutations predispose to both familial MNG and MNG with SLCT, independent of PPB and germline DICER1 mutations lead to dysregulation of miRNA. This could be investigated further as a possible novel mechanism of tumorigenesis. PMID:21205968

  8. Correlation of protein kinase activation and testosterone production after stimulation of Leydig cells with luteinizing hormone.

    PubMed Central

    Cooke, B A; Lindh, M L; Janszen, F H

    1976-01-01

    The effect of different doses of luteinizing hormone on activation of protein kinases, cyclic AMP and testosterone production was studied in purified rat testis Leydig-cell preparations in the presence of 3-isobutyl-1-methylxanthine (a phosphodiesterase inhibitor). In addition, the nature of the protein kinases present in these cells and other tissues was investigated. The following results were obtained. 1. With all the amounts of luteinizing hormone used (0.1-1000 ng/ml), both activation of protein kinase and stimulation of testosterone production were demonstrated. With the lowest amount of luteinizing hormone (0.1 ng/ml), an 8.4+/-0.9% (S.E.M.,n=6) stimulation of protein kinase activation occurred, increasing to 100% with 1000 ng/ml, compared with 3.2+/-1.0%(S.E.M.,n=7) and 100% stimulation of testosterone production with 0.1 and 100 ng/ml respectively. 2. With amounts of luteinizing hormone up to 1 ng/ml (which gave half-maximal stimulation of testosterone production) no detectable increases in net cyclic AMP production were obtained. With higher amounts of luteinizing hormone, cyclic AMP production increased, but maximal production was not reached with 1000 ng/ml. 3. Two isoenzymic forms of protein kinase were present in Leydig cells and seminiferous tubules; type I was eluted with 0.075 M-and type II with 0.22-0.25 m-NaCl from DEAE-cellulose columns. 4. The protein kinase activity was not affected by the presence of erythrocytes in the Leydig-cell preparation, but varied depending on the type of histone used as substrate (histone F2b greater than mixed greater than histone F1). PMID:189752

  9. The co-occurrence of an ovarian Sertoli-Leydig cell tumor with a thyroid carcinoma is highly suggestive of a DICER1 syndrome.

    PubMed

    Durieux, Emeline; Descotes, Françoise; Mauduit, Claire; Decaussin, Myriam; Guyetant, Serge; Devouassoux-Shisheboran, Mojgan

    2016-05-01

    The DICER1 gene encodes an endoribonuclease involved in the production of mature microRNAs which regulates gene expression through several mechanisms. Carriers of germline DICER1 mutations are predisposed to a rare cancer syndrome, the DICER1 syndrome. Pleuropulmonary blastoma is the most frequent lesion seen in this syndrome. Thyroid abnormalities are also a common finding, essentially concerning multinodular goiter. However, differentiated thyroid carcinoma is infrequently seen in such pedigrees. In addition to germline DICER1 mutations, specific somatic mutations have been identified in the DICER1 RNase IIIb catalytic domain in several tumor types, including ovarian Sertoli-Leydig cell tumors. We report two cases of differentiated thyroid carcinoma associated with ovarian Sertoli-Leydig cell tumor and with a heterozygous DICER1 gene mutation, occurring in two unrelated young girls without pleuropulmonary blastoma. Both thyroid carcinomas showed an E1813 mutation in exon 25 while the ovarian tumors harboured a somatic mutation in E1705 in exon 24 and a D1709 mutation in exon 25. Our observations confirm that the occurrence of an ovarian Sertoli-Leydig cell tumor with a thyroid carcinoma is highly suggestive of a DICER1 syndrome. We contend that the possibility of a relationship between sporadic thyroid carcinoma in young patients and somatic DICER1 gene mutation needs further investigation. PMID:26983701

  10. Chemical Shift Images of Organelles in Leydig cells of Mice Testes

    NASA Astrophysics Data System (ADS)

    Ejima, T.; Neichi, Y.; Yanagihara, M.; Kado, M.; Ishino, M.; Yasuda, K.; Tamotsu, S.

    2013-10-01

    Soft X-ray transmission images of Leydig cells of mice testes changing incident wavelength were observed with the use of a contact microscope. After normalization of transmission images, absorbance images were obtained and compared with a visible differential interference image. Some organelles were identified by the image comparison, and absorption spectra of the organelles were obtained from the absorbance images. The absorption spectra show that peak structures are different depending on the observed organelles. The structures and the positions of organelles were clearly identified at C-K absorption.

  11. Increasing insulin resistance is associated with a decrease in Leydig cell testosterone secretion in men.

    PubMed

    Pitteloud, Nelly; Hardin, Megan; Dwyer, Andrew A; Valassi, Elena; Yialamas, Maria; Elahi, Dariush; Hayes, Frances J

    2005-05-01

    Insulin resistance is associated with low testosterone (T) levels in men, the mechanism of which is unclear. Thus, the aim of this study was to evaluate the hypothalamic-pituitary-gonadal axis in men with a spectrum of insulin sensitivity. Twenty-one men (aged 25-65 yr) had a glucose tolerance test and assessment of insulin sensitivity using a hyperinsulinemic-euglycemic clamp. Insulin sensitivity, expressed as the M value (milligrams per kilograms(-1) per minute(-1)), was calculated from the glucose disposal rate during the final 30 min of the clamp. Eighteen subjects had blood sampling every 10 min for 12 h to assess LH pulsatility. Hypogonadism was then induced with a GnRH antagonist, followed by sequential stimulation testing with GnRH (750 ng/kg, iv) and human chorionic gonadotropin (hCG; 1000 IU, im) to assess pituitary and testicular responsiveness, respectively. Nine subjects had normal glucose tolerance, nine had impaired glucose tolerance, and three had diabetes mellitus. There was a positive relationship between M and T levels (r = 0.46; P < 0.05). No relationship was seen between M and parameters of LH secretion, including mean LH levels, LH pulse amplitude, LH pulse frequency, and LH response to exogenous GnRH administration. In contrast, a strong correlation was observed between M and the T response to hCG (r = 0.73; P < 0.005). Baseline T levels correlated with the increase in T after hCG administration (r = 0.47; P < 0.05). During the clamp, T levels increased from a baseline level of 367 +/- 30 to 419 +/- 38 ng/dl during the last 30 min (P < 0.05). From these data we conclude that insulin resistance is associated with a decrease in Leydig cell T secretion in men. Additional studies are required to determine the mechanism of this effect. PMID:15713702

  12. Effects of polychlorinated biphenyls (PCBs) on in vitro biosynthesis of testosterone and cell viability in mouse Leydig cells

    SciTech Connect

    Johansson, B.

    1989-01-01

    Some PCBs (polychlorinated biphenyls) show a tendency to accumulate in steroid-producing organs such as the adrenals, testes and ovaries. Moreover, some hexachlorobiphenyls are accumulated in the interstitial part of the testis, where the steroid-producing cells are located (Brandt 1977). In an earlier study (Johansson 1987) the authors investigated the in vivo effects of PCBs on mice. They could not find any evidence for effects of Clophen A50 and 2,2',4,4',5,5'-hexachlorobiphenyl on plasma testosterone levels or on the ability of the Leydig cells to respond to luteinizing hormone (LH). Despite these results they wanted to determine whether PCBs have any effect on testosterone synthesis when administered to Leydig cells in vitro, since it has been shown earlier that a substance having no effects on testosterone synthesis when given in vivo can have drastic effects when administered in vitro.

  13. Lactogen receptors in rat Leydig cells: analysis of their structure with bifunctional cross-linking reagents

    SciTech Connect

    Bonifacino, J.S.; Dufau, M.L.

    1985-04-01

    (/sup 125/I)Iodohuman GH was found to bind to receptors with specificity for lactogenic hormones in a Triton X-100 extract from Leydig cell membranes displaying an affinity constant of 3.8 X 10(/sup 9/) M-1 and a binding capacity of 167 fmol/mg protein. Cross-linking of solubilized (/sup 125/I)iodohuman GH-receptor complexes with disuccinimidyl suberate followed by analysis by sodium dodecyl sulfate-gel electrophoresis in the presence of beta-mercaptoethanol and autoradiography resulted in the appearance of bands with apparent mol wt of 113,000, 103,000, 59,000, and 53,000. The appearance of these bands was prevented by incubation in the presence of lactogenic hormones. By using a two-dimensional electrophoresis technique (first dimension under nonreducing conditions; second dimension under reducing conditions), it was demonstrated that a fraction of the mol wt 59,000 species can be released from the mol wt 103,000 species upon cleavage of disulfide bonds. These results suggest the existence of lactogen receptor species with approximate mol wt of 91,000, 81,000, 37,000, and 31,000 in Triton X-100 extracts from Leydig cell membranes if the contribution of the free hormone (mol wt, 22,000) is subtracted. A fraction of the mol wt 37,000 subunits appears to be contained within the 81,000 species linked through disulfide bonds.

  14. Endocytosis of lutropin by Leydig cells through a pathway distinct from the high-affinity receptor.

    PubMed

    Bozon, V; Pajot-Augy, E; Vignon, X; Salesse, R

    1998-08-25

    In porcine Leydig cells in primary culture, 95% of the internalization of [125I]porcine lutropin ([125I]pLH, which bears sulfated GalNAc) could not be ascribed to the high-affinity LH receptor (LHR). In contrast, >40% of [125I]human choriogonadotropin (hCG, with sialylated sugar chains) uptake was performed by the LHR itself. When the LHR was down-regulated by excess unlabeled hormone, the LHR-independent incorporation of [125I]pLH could be inhibited in a dose-dependent fashion by sulfated polysaccharides such as fucoidan or chondroitin-(4 or 6)-sulfate, but not by other polyanionic compounds, nor by sulfated chondroitin disaccharides. Endocytosis occurred through a clathrin-dependent pathway and was inhibited by low temperature, endocytosis inhibitors, increased ionic strength, or by EDTA and dithiothreitol. Taken together, these results suggest that a Leydig cell membrane protein (possibly a lectin, or a glycosaminoglycan receptor) could perform specific LH clearance in the testis via recognition of its sulfated sugars. PMID:9806348

  15. Estrogenic compounds inhibit gap junctional intercellular communication in mouse Leydig TM3 cells

    SciTech Connect

    Iwase, Yumiko . E-mail: Iwase.Yumiko@mg.m-pharma.co.jp; Fukata, Hideki . E-mail: fukata@faculty.chiba-u.jp; Mori, Chisato . E-mail: cmori@faculty.chiba-u.jp

    2006-05-01

    Some estrogenic compounds are reported to cause testicular disorders in humans and/or experimental animals by direct action on Leydig cells. In carcinogenesis and normal development, gap junctional intercellular communication (GJIC) plays an essential role in maintaining homeostasis. In this study, we examine the effects of diethylstilbestrol (DES, a synthetic estrogen), 17{beta}-estradiol (E{sub 2}, a natural estrogen), and genistein (GEN, a phytoestrogen) on GJIC between mouse Leydig TM3 cells using Lucifer yellow microinjection. The three compounds tested produced GJIC inhibition in the TM3 cells after 24 h. Gradually, 10 {mu}M DES began to inhibit GJIC for 24 h and this effect was observed until 72 h. On the other hand, both 20 {mu}M E{sub 2} and 25 {mu}M GEN rapidly inhibited GJIC in 6 h and 2 h, respectively. The effects continued until 24 h, but weakened by 72 h. Furthermore, a combined effect at {mu}M level between DES and E{sub 2} on GJIC inhibition was observed, but not between GEN and E{sub 2}. DES and E{sub 2} showed GJIC inhibition at low dose levels (nearly physiological estrogen levels) after 72 h, but GEN did not. DES-induced GJIC inhibition at 10 pM and 10 {mu}M was completely counteracted by ICI 182,780 (ICl), an estrogen receptor antagonist. On the other hand, the inhibitory effects on GJIC with E{sub 2} (10 pM and 20 {mu}M) and GEN (25 {mu}M) were partially blocked by ICI or calphostin C, a protein kinase C (PKC) inhibitor, and were completely blocked by the combination of ICI and calphostin C. These results demonstrate that DES inhibits GJIC between Leydig cells via the estrogen receptor (ER), and that E{sub 2} and GEN inhibit GJIC via ER and PKC. These estrogenic compounds may have different individual nongenotoxic mechanism including PKC pathway on testicular carcinogenesis or development.

  16. Toxic mechanisms of 3-monochloropropane-1,2-diol on progesterone production in R2C rat leydig cells.

    PubMed

    Sun, Jianxia; Bai, Shun; Bai, Weibin; Zou, Feiyan; Zhang, Lei; Su, Zhijian; Zhang, Qihao; Ou, Shiyi; Huang, Yadong

    2013-10-16

    3-Monochloropropane-1,2-diol (3-MCPD) is a well-known food processing contaminant that has been shown to impede the male reproductive function. However, its mechanism of action remains to be elucidated. In this study, the effects of 3-MCPD on progesterone production were investigated using R2C Leydig cells. 3-MCPD caused concentration-dependent inhibition of cell viability at the IC25, IC50, and IC75 levels of 1.027, 1.802, and 3.160 mM, respectively. Single cell gel/comet assay and atomic force microscopy assay showed that 3-MCPD significantly induced early apoptosis. In addition, 3-MCPD significantly reduced progesterone production by reducing the expression of cytochrome P450 side-chain cleavage enzyme, steroidogenic acute regulatory protein, and 3β-hydroxysteroid dehydrogenase in R2C cells. The change in steroidogenic acute regulatory protein expression was highly consistent with progesterone production. Furthermore, the mitochondrial membrane potential and cAMP significantly decreased. PMID:24040863

  17. Ultrastructural Studies of Germ Cell Development and the Functions of Leydig Cells and Sertoli Cells associated with Spermatogenesis in Kareius bicoloratus (Teleostei, Pleuronectiformes, Pleuronectidae)

    PubMed Central

    Kang, Hee-Woong; Kim, Sung Hwan; Chung, Jae Seung

    2016-01-01

    The ultrastructures of germ cells and the functions of Leydig cells and Sertoli cells during spermatogenesis inmale Kareius bicoloratus (Pleuronectidae) were investigated by electron microscope observation. Each of the well-developed Leydig cells during active maturation division and before spermiation contained an ovoid vesicular nucleus, a number of smooth endoplasmic reticula, well-developed tubular or vesicular mitochondrial cristae, and several lipid droplets in the cytoplasm. It is assumed that Leydig cells are typical steroidogenic cells showing cytological characteristics associated with male steroidogenesis. No cyclic structural changes in the Leydig cells were observed through the year. However, although no clear evidence of steroidogenesis or of any transfer of nutrients from the Sertoli cells to spermatogenic cells was observed, cyclic structural changes in the Sertoli cells were observed over the year. During the period of undischarged germ cell degeneration after spermiation, the Sertoli cells evidenced a lysosomal system associated with phagocytic function in the seminiferous lobules. In this study, the Sertoli cells function in phagocytosis and the resorption of products originating from degenerating spermatids and spermatozoa after spermiation. The spermatozoon lacks an acrosome, as have been shown in all teleost fish spermatozoa. The flagellum or sperm tail of this species evidences the typical 9+2 array of microtubules. PMID:27294207

  18. Cytoprotective effects of fruit pulp of Eugenia jambolana on H 2 O 2 -induced oxidative stress and apoptosis in rat Leydig cells in vitro.

    PubMed

    Anand, H; Misro, M M; Sharma, S B; Prakash, S

    2013-06-01

    This study was undertaken to investigate the cytoprotective effect of the fruit pulp of Eugenia jambolana (50-250 μg ml(-1) ) against the damage induced by H 2 O 2 (100 μm) exposure to Leydig cells in vitro. Cell survival with extract was found comparable to similar effects by N-acetyl-l-cysteine. H 2 O 2 -induced rise in thiobarbituric acid reactive substance formation and decline in the activity and expression of antioxidant enzymes like superoxide dismutase, catalase and glutathione-s-transferase were effectively checked. Cellular glutathione and total antioxidant capacity demonstrated significant improvement. The increase in expression of inducible nitric oxide (NO) synthase leading to NO production was successfully countered. Co-treatment of the extract helped in the down-regulation of caspase-3 and poly-ADP-ribose polymerase resulting in a significant reduction in Leydig cell apoptosis induced by H 2 O 2 . Upstream marker proteins of extrinsic (caspase-8, Fas, FasL) and intrinsic (caspase-9) pathway of metazoan apoptosis were identically down-regulated. The Bcl-2 family of proteins, though, remained unaffected. The extract also positively modulated the other marker proteins like c-Jun NH 2 -terminal kinase, p38, Akt, nuclear factor-κB, c-Fos, cellular FLICE-inhibitory protein, cyclooxygenase-2 and p53. Taken together, the above-mentioned findings establish the anti-oxidative and anti-apoptotic potency of the extract that ameliorates the H 2 O 2 -induced adverse effects on rat Leydig cells in vitro. PMID:22731239

  19. Stimulation of progesterone production by phorbol-12-myristate 13-acetate (PMA) in cultured Leydig tumor cells

    SciTech Connect

    Chaudhary, L.R.; Raju, V.S.; Stocco, D.M.

    1987-05-01

    It has been shown that addition of hCG or c-AMP to cultured Leydig tumor cells (MA-10) increases synthesis of progesterone as the major steroid. To investigate the possible involvement of protein kinase C (PK-C) in the regulation of steroid synthesis, the authors have studied the effect of PMA, an activator of PK-C, on progesterone production in MA-10 cells. The addition of PMA (100 ng/ml) stimulated steroid production whereas 4 -phorbol-12,13-didecanoate, an inactive phorbol ester, did not have any effects. Like hCG and c-AMP, PMA-stimulated progesterone production was inhibited by cycloheximide. hCG-stimulated steroid synthesis was inhibited by PMA. The addition of PMA to MA-10 Leydig cells further increased the c-AMP-stimulated progesterone production. To determine whether c-AMP has a obligatory role in the regulation of steroid production, the effect of adenylate cyclase inhibitor, 9-(tetrahydro-2-furyl)adenine (TFA), was studied on progesterone production in the presence of hCG. At lower dose (17 ng/ml) hCG-stimulated intracellular c-AMP levels and steroid production were inhibited by TFA (300 M). At higher dose of hCG (34 ng/ml) TFA did not inhibit the hCG-stimulated intracellular c-AMP levels, however, progesterone production was inhibited. Results suggest that the action of hCG, c-AMP and PMA in controlling steroidogenesis might be regulated by similar but different mechanisms.

  20. Ovarian Sertoli-Leydig Cell Tumor with Predominant Heterologous Mucinous Differentiation and Foci of Hepatocytic Differentiation: Case Report and Review of The Literature.

    PubMed

    Liang, Li; Menzin, Andrew; Lovecchio, John Louis; Navarro, Maria D

    2015-01-01

    Sertoli-Leydig cell tumor is a rare ovarian neoplasm and belongs to the group of sex cord stromal tumors. We present a case of a 15-year old girl diagnosed with Sertoli-Leydig cell tumor with heterologous elements consisting predominantly of mucinous epithelium and a sparse Sertoli-Leydig cell component, mimicking mucinous neoplasm. Furthermore, foci of hepatocytic differentiation were also identified. Immunohistochemical stains showed the component of Sertoli cell differentiation was positive for cytokeratin 18 and inhibin. The component of Leydig cell differentiation was strongly positive for inhibin. The component of hepatocytic differentiation was positive for low molecular weight keratin, HepPar1, alpha-fetoprotein and weakly positive for inhibin. Thus, this was a very rare case which created a challenge for pathologists, especially on frozen sections. PMID:26116602

  1. Orally applied doxazosin disturbed testosterone homeostasis and changed the transcriptional profile of steroidogenic machinery, cAMP/cGMP signalling and adrenergic receptors in Leydig cells of adult rats.

    PubMed

    Stojkov, N J; Janjic, M M; Kostic, T S; Andric, S A

    2013-03-01

    Doxazosin (Doxa) is an α1-selective adrenergic receptor (ADR) antagonist widely used, alone or in combination, to treat high blood pressure, benign prostatic hyperplasia symptoms, and recently has been suggested as a potential drug for prostate cancer prevention/treatment. This study was designed to evaluate the effect of in vivo Doxa po-application, in clinically relevant dose, on: (i) steroidogenic machinery homeostasis; (ii) cAMP/cGMP signalling; (iii) transcription profile of ADR in Leydig cells of adult rats. The results showed that po-application of Doxa for once (1×Doxa), or for two (2×Doxa) or 10 (10×Doxa) consecutive days significantly disturbed steroidogenic machinery homeostasis in Leydig cells. Doxa po-application significantly decreased circulating luteinizing hormone and androgens levels. The level of androgens in testicular interstitial fluid and that extracted from testes obtained from 1×Doxa/2×Doxa rats decreased, although it remained unchanged in 10×Doxa rats. Similarly, the ex vivo basal androgen production followed in testes isolated from 1×Doxa/2×Doxa rats decreased, while remained unchanged in 10×Doxa rats. Differently, ex vivo testosterone production and steroidogenic capacity of Leydig cells isolated from 1×Doxa/2×Doxa rats was stimulated, while 10×Doxa had opposite effect. In the same cells, cAMP content/release showed similar stimulatory effect, but back to control level in Leydig cells of 10×Doxa. 1×Doxa/2×Doxa decreased transcripts for cAMP specific phosphodiesterases Pde7b/Pde8b, whereas 10×Doxa increased Pde4d. All types of treatment reduced the expression of genes encoding protein kinase A (PRKA) regulatory subunit (Prkar2b), whereas only 10×Doxa stimulated catalytic subunit (Prkaca). Doxa application more affected cGMP signalling: stimulated transcription of constitutive nitric oxide synthases (Nos1, Nos3) in time-dependent manner, whereas reduced inducible Nos2. 10×Doxa increased guanylyl cyclase 1 transcript and

  2. Impaired 17,20-Lyase Activity in Male Mice Lacking Cytochrome b5 in Leydig Cells.

    PubMed

    Sondhi, Varun; Owen, Bryn M; Liu, Jiayan; Chomic, Robert; Kliewer, Steven A; Hughes, Beverly A; Arlt, Wiebke; Mangelsdorf, David J; Auchus, Richard J

    2016-04-01

    Androgen and estrogen biosynthesis in mammals requires the 17,20-lyase activity of cytochrome P450 17A1 (steroid 17-hydroxylase/17,20-lyase). Maximal 17,20-lyase activity in vitro requires the presence of cytochrome b5 (b5), and rare cases of b5 deficiency in human beings causes isolated 17,20-lyase deficiency. To study the consequences of conditional b5 removal from testicular Leydig cells in an animal model, we generated Cyb5(flox/flox):Sf1-Cre (LeyKO) mice. The LeyKO male mice had normal body weights, testis and sex organ weights, and fertility compared with littermates. Basal serum and urine steroid profiles of LeyKO males were not significantly different than littermates. In contrast, marked 17-hydroxyprogesterone accumulation (100-fold basal) and reduced testosterone synthesis (27% of littermates) were observed after human chorionic gonadotropin stimulation in LeyKO animals. Testis homogenates from LeyKO mice showed reduced 17,20-lyase activity and a 3-fold increased 17-hydroxylase to 17,20-lyase activity ratio, which were restored to normal upon addition of recombinant b5. We conclude that Leydig cell b5 is required for maximal androgen synthesis and to prevent 17-hydroxyprogesterone accumulation in the mouse testis; however, the b5-independent 17,20-lyase activity of mouse steroid 17-hydroxylase/17,20-lyase is sufficient for normal male genital development and fertility. LeyKO male mice are a good model for the biochemistry but not the physiology of isolated 17,20-lyase deficiency in human beings. PMID:26974035

  3. Impaired 17,20-Lyase Activity in Male Mice Lacking Cytochrome b5 in Leydig Cells

    PubMed Central

    Sondhi, Varun; Owen, Bryn M.; Liu, Jiayan; Chomic, Robert; Kliewer, Steven A.; Hughes, Beverly A.; Arlt, Wiebke; Mangelsdorf, David J.

    2016-01-01

    Androgen and estrogen biosynthesis in mammals requires the 17,20-lyase activity of cytochrome P450 17A1 (steroid 17-hydroxylase/17,20-lyase). Maximal 17,20-lyase activity in vitro requires the presence of cytochrome b5 (b5), and rare cases of b5 deficiency in human beings causes isolated 17,20-lyase deficiency. To study the consequences of conditional b5 removal from testicular Leydig cells in an animal model, we generated Cyb5flox/flox:Sf1-Cre (LeyKO) mice. The LeyKO male mice had normal body weights, testis and sex organ weights, and fertility compared with littermates. Basal serum and urine steroid profiles of LeyKO males were not significantly different than littermates. In contrast, marked 17-hydroxyprogesterone accumulation (100-fold basal) and reduced testosterone synthesis (27% of littermates) were observed after human chorionic gonadotropin stimulation in LeyKO animals. Testis homogenates from LeyKO mice showed reduced 17,20-lyase activity and a 3-fold increased 17-hydroxylase to 17,20-lyase activity ratio, which were restored to normal upon addition of recombinant b5. We conclude that Leydig cell b5 is required for maximal androgen synthesis and to prevent 17-hydroxyprogesterone accumulation in the mouse testis; however, the b5-independent 17,20-lyase activity of mouse steroid 17-hydroxylase/17,20-lyase is sufficient for normal male genital development and fertility. LeyKO male mice are a good model for the biochemistry but not the physiology of isolated 17,20-lyase deficiency in human beings. PMID:26974035

  4. Regulation of gonadotropin receptors, gonadotropin responsiveness, and cell multiplication by somatomedin-C and insulin in cultured pig Leydig cells

    SciTech Connect

    Bernier, M.; Chatelain, P.; Mather, J.P.; Saez, J.M.

    1986-11-01

    The author have investigated the effects of insulin and somatomedin-C/insulin like growth factor I(Sm-C) in purified porcine Leydig cells in vitro on gonadotrophins (hCG) receptor number, hCG responsiveness (cAMP and testosterone production), and thymidine incorporation into DNA. Leydig cells cultured in a serum-free medium containing transferrin, vitamin E, and insulin (5 ..mu..g/ml) maintained fairly constant both hCG receptors and hCG responsiveness. When they were cultured for 3 days in the same medium without insulin, there was a dramatic decline (more than 80%) in both hCG receptor number and hCG responsiveness. However the cAMP but not the testosterone response to forskolin was normal. Both insulin and Sm-C at nanomolar concentrations prevent the decline of both hCG receptors and hCG-induced cAMP production. At nanomolar concentrations, Sm-C and insulin enhanced hCG-induced testosterone production but the effect of Sm-C was significantly higher than that of insulin. However, the effect of insulin at higher concentrations (5 ..mu..g/ml) was significantly higher than that of Sm-C at 50 ng/ml. In contrast, at nanomolar concentrations only Sm-C stimulated (/sup 3/H)-thymidine incorporation into DNA and cell multiplication, the stimulatory effect of insulin on these parameters, was seen only at micromolar concentrations. These results indicate that both Sm-C and insulin acting through the receptors increase Leydig cell steroidogenic responsiveness to hCG by increasing hCG receptor number and improving some step beyond cAMP formation. In contrast, the mitogenic effects of insulin are mediated only through Sm-C receptors.

  5. Feeding hydroalcoholic extract powder of Lepidium meyenii (maca) increases serum testosterone concentration and enhances steroidogenic ability of Leydig cells in male rats.

    PubMed

    Ohta, Y; Yoshida, K; Kamiya, S; Kawate, N; Takahashi, M; Inaba, T; Hatoya, S; Morii, H; Takahashi, K; Ito, M; Ogawa, H; Tamada, H

    2016-04-01

    Although Lepidium meyenii (maca), a plant growing in Peru's central Andes, has been traditionally used for enhancing fertility and reproductive performance in domestic animals and human beings, effects of maca on reproductive organs are still unclear. This study examined whether feeding the hydroalcoholic extract powder of maca for 6 weeks affects weight of the reproductive organs, serum concentrations of testosterone and luteinising hormone (LH), number and cytoplasmic area of immunohistochemically stained Leydig cells, and steroidogenesis of cultured Leydig cells in 8-week-old male rats. Feeding the extract powder increased weight of seminal vesicles, serum testosterone level and cytoplasmic area of Leydig cells when compared with controls. Weight of prostate gland, serum LH concentration and number of Leydig cells were not affected by the maca treatment. The testosterone production by Leydig cells significantly increased when cultured with 22R-hydroxycholesterol or pregnenolone and tended to increase when cultured with hCG by feeding the extract powder. The results show that feeding the hydroalcoholic extract powder of maca for 6 weeks increases serum testosterone concentration associated with seminal vesicle stimulation in male rats, and this increase in testosterone level may be related to the enhanced ability of testosterone production by Leydig cells especially in the metabolic process following cholesterol. PMID:26174043

  6. Precocious Puberty and Leydig Cell Hyperplasia in Male Mice With a Gain of Function Mutation in the LH Receptor Gene

    PubMed Central

    McGee, Stacey R.

    2013-01-01

    The LH receptor (LHR) is critical for steroidogenesis and gametogenesis. Its essential role is underscored by the developmental and reproductive abnormalities that occur due to genetic mutations identified in the human LHR. In males, activating mutations are associated with precocious puberty and Leydig cell hyperplasia. To generate a mouse model for the human disease, we have introduced an aspartic acid to glycine mutation in amino acid residue 582 (D582G) of the mouse LHR gene corresponding to the most common D578G mutation found in boys with familial male-limited precocious puberty (FMPP). In transfected cells, mouse D582G mLHR exhibited constitutive activity with a 23-fold increase in basal cAMP levels compared with the wild-type receptor. A temporal study of male mice from 7 days to 24 weeks indicated that the knock-in mice with the mutated receptor (KiLHRD582G) exhibited precocious puberty with elevated testosterone levels as early as 7 days of age and through adulthood. Leydig cell-specific genes encoding LHR and several steroidogenic enzymes were up-regulated in KiLHRD582G testis. Leydig cell hyperplasia was detected at all ages, whereas Sertoli and germ cell development appeared normal. A novel finding from our studies, not previously reported in the FMPP cases, is that extensive hyperplasia is commonly found around the periphery of the testis. We further demonstrate that the hyperplasia is due to premature proliferation and precocious differentiation of adult Leydig cells in the KiLHRD582G testis. The KiLHRD582G mice provide a mouse model for FMPP, and we suggest that it is a useful model for studying pathologies associated with altered LHR signaling. PMID:23861372

  7. Lutropin/choriogonadotropin (LH/CG) stimulate the proliferation of primary cultures of rat Leydig cells through a pathway that involves activation of the ERK1/2 cascade*

    PubMed Central

    Shiraishi, Koji; Ascoli, Mario

    2007-01-01

    Primary cultures of progenitor and immature rat Leydig cells were established from the testes of 21 and 35 day old rats, respectively. The cell population remained homogeneous after 4–6 days in culture as judged by staining for 3β-hydroxysteroid dehydrogenase but the cells were unable to bind 125I-hCG or to respond to hCG with classical LH receptor (LHR)-mediated responses including cAMP and inositol phosphate accumulation, steroid biosynthesis or the phosphorylation of the extracellular regulated kinases 1/2 (ERK1/2). Infection of primary cultures with recombinant adenovirus coding for β-galactosidase showed that ~65% of the cells are infected. Infection with adenovirus coding for the human LHR (hLHR) allowed for expression of the hLHR at a density of ~25,000 receptors/cell and allowed the cells to respond to hCG with increases in cAMP and inositol phosphate accumulation, steroid biosynthesis and the phosphorylation of ERK1/2. Although progenitor and immature cells were able to respond to hCG with an increase in progesterone, only the immature cells responded with an increase in testosterone. In addition to these classical LHR-mediated responses the primary cultures of progenitor or immature rat Leydig cells expressing the recombinant hLHR proliferated robustly when incubated with hCG and this proliferative response was sensitive to an inhibitor of ERK1/2 phosphorylation. These studies establish a novel experimental paradigm that can be used to study the proliferative response of Leydig cells to LH/CG. We conclude that activation of the LHR-provoked Leydig cell proliferation requires activation of the ERK1/2 cascade. PMID:17412805

  8. Label-free based quantitative proteomics analysis of primary neonatal porcine Leydig cells exposed to the persistent contaminant 3-methylsulfonyl-DDE.

    PubMed

    Kalayou, Shewit; Granum, Cesilie; Berntsen, Hanne Friis; Groseth, Per Kristian; Verhaegen, Steven; Connolly, Lisa; Brandt, Ingvar; de Souza, Gustavo Antonio; Ropstad, Erik

    2016-03-30

    Evidence that persistent environmental pollutants may target the male reproductive system is increasing. The male reproductive system is regulated by secretion of testosterone by testicular Leydig cells, and perturbation of Leydig cell function may have ultimate consequences. 3-Methylsulfonyl-DDE (3-MeSO2-DDE) is a potent adrenal toxicants formed from the persistent insecticide DDT. Although studies have revealed the endocrine disruptive effect of 3-MeSO2-DDE, the underlying mechanisms at cellular level in steroidogenic Leydig cells remains to be established. The current study addresses the effect of 3-MeSO2-DDE on viability, hormone production and proteome response of primary neonatal porcine Leydig cells. The AlamarBlue™ assay was used to evaluate cell viability. Solid phase radioimmunoassay was used to measure concentration of hormones produced by both unstimulated and Luteinizing hormone (LH)-stimulated Leydig cells following 48h exposure. Protein samples from Leydig cells exposed to a non-cytotoxic concentration of 3-MeSO2-DDE (10μM) were subjected to nano-LC-MS/MS and analyzed on a Q Exactive mass spectrometer and quantified using label-free quantitative algorithm. Gene Ontology (GO) and Ingenuity Pathway Analysis (IPA) were carried out for functional annotation and identification of protein interaction networks. 3-MeSO2-DDE regulated Leydig cell steroidogenesis differentially depending on cell culture condition. Whereas its effect on testosterone secretion at basal condition was stimulatory, the effect on LH-stimulated cells was inhibitory. From triplicate experiments, a total of 6804 proteins were identified in which the abundance of 86 proteins in unstimulated Leydig cells and 145 proteins in LH-stimulated Leydig cells was found to be significantly regulated in response to 3-MeSO2-DDE exposure. These proteins not only are the first reported in relation to 3-MeSO2-DDE exposure, but also display small number of proteins shared between culture conditions

  9. Binding and internalization in vivo of (/sup 125/I)hCG in Leydig cells of the rat

    SciTech Connect

    Hermo, L.; Lalli, M.

    1988-01-01

    The present study was performed to demonstrate the binding, mode of uptake, pathway and fate of iodinated human chorionic gonadotropin ((/sup 125/I)hCG) by Leydig cells in vivo using electron microscope radioautography. Following a single injection of (/sup 125/I)hCG into the interstitial space of the testis, the animals were fixed by perfusion with glutaraldehyde at 20 minutes, 1, 3, 6 and 24 hours. The electron microscope radioautographs demonstrated a prominent and qualitatively similar binding of the labeled hCG on the microvillar processes of the Leydig cells at 20 minutes, 1, 3, and 6 hours. The specificity of the (/sup 125/I)hCG binding was determined by injecting a 100-fold excess of unlabeled hormone concurrently with the labeled hormone. Under these conditions, the surface, including the microvillar processes of Leydig cells, was virtually unlabeled, indicating that the binding was specific and receptor-mediated. In animals injected with labeled hCG and sacrificed 20 minutes later, silver grains were also seen overlying the limiting membrane of large, uncoated surface invaginations and large subsurface vacuoles with an electron-lucent content referred to as endosomes. A radioautographic reaction was also seen within multivesicular bodies with a pale stained matrix. At 1 hour, silver grains appeared over dense multivesicular bodies and occasionally over secondary lysosomes, in addition to the structures mentioned above, while at 3 and 6 hours, an increasing number of secondary lysosomes became labeled. At 24 hours, binding of (/sup 125/I)hCG to the microvillar processes of Leydig cells persisted but was diminished, although a few endosomes, multivesicular bodies and secondary lysosomes still showed a radioautographic reaction. No membranous tubules that were seen in close proximity to, or in continuity with, endosomes and multivesicular bodies were observed to be labeled at any time interval.

  10. Mono-2-ethylhexyl phthalate stimulates androgen production but suppresses mitochondrial function in mouse leydig cells with different steroidogenic potential.

    PubMed

    Savchuk, Iuliia; Söder, Olle; Svechnikov, Konstantin

    2015-05-01

    Numerous studies have reported on testicular toxicity of phthalates in different experimental paradigms and showed that Leydig cells (LCs) were one of the main targets of phthalate actions. Adverse effects of phthalates on LCs steroidogenesis have been attributed to their metabolites, monophthalates. This study focuses on investigation whether LCs responsiveness to monophthalates action is associated with their potential to produce androgens. We found that of 3 monophthalates investigated [ie, mono-2-ethylhexyl phthalate (MEHP), mono-n-butyl phthalate, and mono-n-benzyl phthalate] only MEHP caused biological effects on the mouse LCs function. This monophthalate stimulated basal steroidogenesis associated with upregulation of StAR protein expression with no effect on hCG-stimulated androgen production by LCs from CBA/Lac and C57BL/6j mouse genotypes were observed. Further, MEHP attenuated ATP production and increased superoxide generation by both phenotypes of mouse LCs that indicated on mitochondrial dysfunction induced by the monophthalate. All together, our data indicate that MEHP-mediated stimulation of steroidogenesis and perturbation in mitochondrial function are not associated with the capacity of the LCs to synthesize androgens. We suggest that this effect of MEHP observed in LCs of rodent origin needs to be taken into consideration in analysis of earlier start of puberty in boys and may highlight a possible influence of phthalates on reproductive health in males. PMID:25677926

  11. Increased Proliferation but Decreased Steroidogenic Capacity in Leydig Cells from Mice Lacking Cyclin-Dependent Kinase Inhibitor 1B1

    PubMed Central

    Lin, Han; Hu, Guo-Xin; Dong, Lei; Dong, Qiang; Mukai, Motoko; Chen, Bing-Bing; Holsberger, Denise R.; Sottas, Chantal M.; Cooke, Paul S.; Lian, Qing-Quan; Li, Xiao-Kun; Ge, Ren-Shan

    2009-01-01

    Proliferating cells express cyclins, cell cycle regulatory proteins that regulate the activity of cyclin-dependent kinases (CDKs). The actions of CDKs are regulated by specific inhibitors, the CDK inhibitors (CDKIs), which are comprised of the Cip/Kip and INK4 families. Expression of the Cip/Kip CDKI 1B (Cdkn1b, encoding protein CDKN1B, also called p27kip1) in developing Leydig cells (LCs) has been reported, but the function of CDKN1B in LCs is unclear. The goal of the present study was to determine the effects of CDKN1B on LC proliferation and steroidogenesis by examining these parameters in Cdkn1b knockout (Cdkn1b−/−) mice. LC proliferation was measured by bromodeoxyuridine incorporation. Testicular testosterone levels, mRNA levels, and enzyme activities of steroidogenic enzymes were compared in Cdkn1b−/− and Cdkn1b+/+ mice. The labeling index of LCs in Cdkn1b−/− mice was 1.5% ± 0.2%, almost 7-fold higher than 0.2% ± 0.08% (P < 0.001) in the Cdkn1b+/+ control mice. LC number per testis in Cdkn1b−/− mice was 2-fold that seen in the Cdkn1b+/+ control mice. However, testicular testosterone levels, mRNA levels of steroidogenic acute regulatory protein (Star), cholesterol side-chain cleavage enzyme (Cyp11a1), and 3beta-hydroxtsteroid dehydrogenase 6 (Hsd3b6), and their respective proteins, were significantly lower in Cdkn1b−/− mice. We conclude that deficiency of CDKN1B increased LC proliferation, but decreased steroidogenesis. Thus, CDKN1B is an important regulator of LC development and function. PMID:19211806

  12. Ovarian Sertoli-Leydig cell tumor with heterologous elements of gastrointestinal type associated with elevated serum alpha-fetoprotein level: an unusual case and literature review

    PubMed Central

    Horta, Mariana; Cunha, Teresa Margarida; Marques, Rita Canas; Félix, Ana

    2014-01-01

    Here we describe the case of a 19-year-old woman with a poorly differentiated ovarian Sertoli-Leydig cell tumor and an elevated serum alpha-fetoprotein level. The patient presented with diffuse abdominal pain and bloating. Physical examination, ultrasound, and magnetic resonance imaging revealed a right ovarian tumor that was histopathologically diagnosed as a poorly differentiated Sertoli-Leydig cell tumor with heterologous elements. Her alpha-fetoprotein serum level was undetectable after tumor resection. Sertoli-Leydig cell tumors are rare sex cord-stromal tumors that account for 0.5% of all ovarian neoplasms. Sertoli-Leydig cell tumors tend to be unilateral and occur in women under 30 years of age. Although they are the most common virilizing tumor of the ovary, about 60% are endocrine-inactive tumors. Elevated serum levels of alpha-fetoprotein are rarely associated with Sertoli-Leydig cell tumors, with only approximately 30 such cases previously reported in the literature. The differential diagnosis should include common alpha-fetoprotein-producing ovarian entities such as germ cell tumors, as well as other non-germ cell tumors that have been rarely reported to produce this tumor marker. PMID:25926909

  13. Combined Leydig cell and Sertoli cell dysfunction in 46,XX males lacking the sex determining region Y gene

    SciTech Connect

    Turner, B.; Vordermark, J.S.; Fechner, P.Y.

    1995-07-03

    We have evaluated 3 individuals with a rare form of 46,XX sex reversal. All of them had ambiguous external genitalia and mixed wolffian and muellerian structures, indicating both Leydig cell and Sertoli cell dysfunction, similar to that of patients with true hermaphroditism. However, gonadal tissue was not ovotesticular but testicular with varying degrees of dysgenesis. SRY sequences were absent in genomic DNA from peripheral leukocytes in all 3 subjects. Y centromere sequences were also absent, indicating that testis development did not occur because of a low level mosaicism of Y-bearing cells. The subjects in this report demonstrate that there is a continuum in the extent of the testis determination in SRY-negative 46,XX sex reversal, ranging from nearly normal to minimal testicular development. 20 refs.

  14. Prevention of deoxynivalenol- and zearalenone-associated oxidative stress does not restore MA-10 Leydig cell functions.

    PubMed

    Savard, Christian; Nogues, Perrine; Boyer, Alexandre; Chorfi, Younes

    2016-02-01

    The worldwide contamination of grains designated to human and animal feeding with Fusarium mycotoxins is a significant problem. Among Fusarium mycotoxins, deoxynivalenol (DON) and zearalenone (ZEA) are the most prevalent mycotoxins found in cereals. Co-occurrence of DON and ZEA is also very frequent and indicates that these mycotoxins might be involved in a wide range of synergistic or additive interactions. Both mycotoxins have been linked to various male reproduction problems including downregulation of steroidogenesis. In this study, the impact of DON and ZEA alone or in combination on the viability and steroid production of Leydig cell line MA-10 was determined. The ability of vitamin E, sesamin and their combination to prevent oxidative stress and restore progesterone secretion in DON- and ZEA-exposed cells was also determined. Results showed that MA-10 cells were more sensitive to the effect of DON compared to ZEA. DON and ZEA also significantly reduced MA-10 progesterone secretion after forskolin activation but no significant interactions between DON and ZEA were detected. Preventive treatment with the combination of vitamin E and sesamin significantly reduced ROS production and increased cell survival after exposition to DON and ZEA. However this treatment failed to restore normal progesterone secretion. In conclusion, both DON and ZEA are deleterious to steroidogenesis in Leydig cells. Prevention of oxidative stress caused by DON and ZEA was effective to restore cell viability but failed to restore other functions of Leydig cells suggesting that ROS production is not the main cause of steroidogenic failure in DON and ZEA treated MA-10 cells. PMID:26783879

  15. The Effects of Imatinib Mesylate on Cellular Viability, Platelet Derived Growth Factor and Stem Cell Factor in Mouse Testicular Normal Leydig Cells

    PubMed Central

    Kheradmand, Fatemeh; Hashemnia, Seyyed Mohammad Reza; Valizadeh, Nasim; Roshan-Milani, Shiva

    2016-01-01

    Background: Growth factors play an essential role in the development of tumor and normal cells like testicular leydig cells. Treatment of cancer with anti-cancer agents like imatinib mesylate may interfere with normal leydig cell activity, growth and fertility through failure in growth factors’ production or their signaling pathways. The purpose of the study was to determine cellular viability and the levels of, platelet derived growth factor (PDGF) and stem cell factor (SCF) in normal mouse leydig cells exposed to imatinib, and addressing the effect of imatinib on fertility potential. Methods: The mouse TM3 leydig cells were treated with 0 (control), 2.5, 5, 10 and 20 μM imatinib for 2, 4 and 6 days. Each experiment was repeated three times (15 experiments in each day).The cellular viability and growth factors levels were assessed by MTT and ELISA methods, respectively. For statistical analysis, one-way ANOVA with Tukey’s post hoc and Kruskal-Wallis test were performed. A p-value less than 0.05 was considered statistically significant. Results: With increasing drug concentration, cellular viability decreased significantly (p<0.05) and in contrast, PDGF levels increased (p<0.05). Different imatinib concentrations had no significant effect on SCF level. Increasing the duration of treatment from 2 to 6 days had no obvious effect on cellular viability, PDGF and SCF levels. Conclusion: Imatinib may reduce fertility potential especially at higher concentrations in patients treated with this drug by decreasing cellular viability. The effect of imatinib on leydig cells is associated with PDGF stimulation. Of course future studies can be helpful in exploring the long term effects of this drug. PMID:27141462

  16. Atypical Leydig cell hyperplasia in adult rats with low T and high LH induced by prenatal Di(n-butyl) phthalate exposure.

    PubMed

    Wakui, Shin; Takahashi, Hiroyuki; Mutou, Tomoko; Shirai, Masaru; Jutabha, Promsuk; Anzai, Naohiko; Wempe, Michael F; Kansaku, Norio; Hano, Hiroshi; Inomata, Tomo; Endou, Hitoshi

    2013-01-01

    The present study describes atypical Leydig cell (LC) hyperplasia in 20-week-old Sprague-Dawley rats with low testosterone and high luteinizing hormone levels after prenatal administration of 100 mg/kg/day di(n-butyl) phthalate on days 12 to 21 postconception. Light microscopy revealed LC hyperplasia surrounded by severely degenerated seminiferous tubules. Aggregated LCs had large ovoid nuclei with nucleoli and abundant eosinophilic cytoplasm. Immunohistochemical analysis showed expression of proliferating cell nuclear antigen and vimentin in many hyperplastic LCs. Electron microscopy revealed atypical nuclei, abundant free ribosomes, stripped rough endoplasmic reticulum, intermediate-size filaments, elongated cytoplasmic filopodia, atypical tight junctions, and cilia formations, but smooth endoplasmic reticulum was scarcely observed. PMID:22968287

  17. Male pseudohermaphoditism with Leydig cell agenesis and persistent muellerian ducts associated with partial deletion of chromosome 13

    SciTech Connect

    Potocki, L.; Oyer, C.E.; Tantravahi, U.

    1994-09-01

    Two chromosomally male infants with partial monosomy 13q were found to have Leydig cell agenesis (LCA) and persistent muellerian ducts (PMD). Post mortem examination in each case revealed cardiovascular, gastrointestinal, genitourinary, musculoskeletal, and central nervous system abnormalities, characteristic of monosomy 13q. Histologic examination confirmed the presence of muellerian derivatives within the pelvis, and the absence of Leydig cells within the testes. Sertoli cells were present. Karyotypes revealed partial monosomy 13q secondary to an unbalanced translocation, der(13)t(1;13)(q43;q21), in one infant, and to a ring chromosome 13 involving a deletion of 13q31-qter, in the other. The etiology of male pseudohermaphroditism is heterogeneous and included PMD due to absence of antimuellerian hormone (AMH) and LCA. Genitourinary abnormalities such as undescended testicles, hypospadias and micropenis have been described in monosomy 13q; however, testicular pathology in these cases has not been described. The cases presented here are the first reported cases in which male pseudohermaphroditism due to LCA and PMD is associated with monosomy 13q. This suggests the genetic locus involved in Leydig cell development may be located on the long arm of chromosome 13. The gene for AMH has been mapped to 19p13.3-13.2. The presence of muellerian structures and Sertoli cells, in the absence of abnormalities of chromosome 19p. suggests there may be genes on 13q coding for an enzyme in the pathway of AMH synthesis or for the AMH receptor. Based on these two cases, the critical region could possibly involve 13q13-qter.

  18. Exposure to phytoestrogens in the perinatal period affects androgen secretion by testicular Leydig cells in the adult rat.

    PubMed

    Akingbemi, Benson T; Braden, Tim D; Kemppainen, Barbara W; Hancock, Karen D; Sherrill, Jessica D; Cook, Sarah J; He, Xiaoying; Supko, Jeffrey G

    2007-09-01

    The use of soy-based products in the diet of infants has raised concerns regarding the reproductive toxicity of genistein and daidzein, the predominant isoflavones in soybeans with estrogenic activity. Time-bred Long-Evans dams were fed diets containing 0, 5, 50, 500, or 1000 ppm of soy isoflavones from gestational d 12 until weaning at d 21 postpartum. Male rats in all groups were fed soy-free diets from postnatal d 21 until 90 d of age. The mean +/- SD concentration of unconjugated (i.e. biologically active) genistein and daidzein in serum from the group of dams maintained on the diet containing the highest amount of isoflavones (1000 ppm) were 17 +/- 27 and 56 +/- 30 nM, respectively, at d 21 postpartum. The concentrations were considerably greater in male offspring (genistein: 73 +/- 46 nM; daidzein: 106 +/- 53 nM). Although steroidogenesis was decreased in individual Leydig cells, male rats from the highest exposure group (1000 ppm diet) exhibited elevated serum levels of the sex steroid hormones androsterone at 21 d (control: 15 +/- 1.5 vs.28 +/- 3.5 ng/ml; P < 0.05) and testosterone at 90 d of age (control: 7.5 +/- 1 vs.17 +/- 2 ng/ml; P < 0.05). Testosterone secretion by immature Leydig cells, isolated from 35-d-old male rats, decreased on exposure to 0.1 nm genistein in vitro (control: 175 +/- 5 vs. 117 +/- 3 ng/10(6) cells per 24 h; P < 0.05), indicative of direct phytoestrogen action. Thus, phytoestrogens have the ability to regulate Leydig cells, and additional studies to assess potential adverse effects of dietary soy-based products on reproductive tract development in neonates are warranted. PMID:17569756

  19. [INVESTIGATIONS OF SUBMICROSCOPIC ARCHITECTONICS SERTOLI AND LEYDIG CELLS AFTER HYDROCHLORIDE SEROTONIN DESTRUCTIVE IMPACT AND THE POSSIBILITY OF CORRECTION BY STIMULANTS OF METABOLIC PROCESSES].

    PubMed

    Brechka, N; Nevzorov, V; Bondarenko, V; Malova, N; Selyukova, N

    2015-01-01

    The results of study of ultrastructural changes in the Sertoli cells and Leydig's cells organelles after destructive influence of the serotonin hydrochloride and under influence bioglobin-U have been presented. It was shown that serotonin hydrochloride causes mitochondrial dysfunction and activates intracellular catabolic processes on the intracellular level. Bioglobin-U increases the activity and reparative synthetic reactions, reduced the degree of mitochondrial dysfunction and catabolic processes and activate the Leydig cell metabolism, and significantly reduces the number of foci destruction membranes of the endoplasmic reticulum, mitochondrial, and membranes of nucleus on the background of serotonin hydrochloride. PMID:26552310

  20. Potassium and chloride conductances in rat Leydig cells: effects of gonadotrophins and cyclic adenosine monophosphate.

    PubMed Central

    Duchatelle, P; Joffre, M

    1990-01-01

    1. The effects of gonadotrophins (luteinizing hormone and human chorionic gonadotrophin) and cyclic AMP on ionic conductances were investigated using the tight-seal whole-cell recording technique in Leydig cells freshly isolated from nature rat testis by enzymatic treatment. 2. In resting cells, the predominant ionic conductance is a voltage-dependent K+ conductance resembling the delayed rectifier K+ conductance of T-lymphocytes. This conductance is characterized by: (1) a time-dependent inactivation for potentials more positive than +20 mV, (2) a reversal potential near -65 mV, (3) a sensitivity to intracellular Cs+, and (4) a sensitivity to extracellular TEA and 4-aminopyridine. 3. A Cl- conductance is also present resembling the Cl- background conductance in squid axons and heart cells. In resting cells, this conductance contributes only a small component of the total outward current obtained with depolarizing pulses. 4. Gonadotrophins (human chorionic gonadotrophin, porcine luteinizing hormone and ovine luteinizing hormone) have little effect on the K+ conductance. They transiently increase a Cl- conductance after a delay of up to 30 s. This response does not occur if the hormones are applied late in the whole-cell recording. Gonadoliberine (GnRH) does not affect the Cl- or K+ conductance. 5. Internal cyclic AMP (100 microM) mimics all these effects while internal application of a GTP-ATP mixture induces a similar response, which is, however, sustained rather than transient. 6. The Cl- conductance was studied quantitatively with a GTP-ATP internal solution. This conductance is activated by depolarizing voltage steps to test potentials of -40 mV or more. Under these conditions, the instantaneous current observed as soon as the depolarizing pulse is applied displays outward rectification and reverses near ECl. During the pulses, a strong inactivation is observed for potentials greater than +40 mV. This conductance is independent of external and internal calcium

  1. A virilizing Leydig cell tumor of the ovary associated with stromal hyperplasia under gonadotropin control.

    PubMed

    Marcondes, J A; Nery, M; Mendonça, B B; Hayashida, S A; Halbe, H W; Carvalho, F M; Wajchenberg, B L

    1997-12-01

    A 34-yr-old nulliparous black woman presented with hair loss, facial hirsutism, irregular menses and infertility associated with greatly increased serum total testosterone levels. The adrenal glands and the ovaries were normal on radiological and ultrasonographic investigation. Catheterization of the veins draining from the adrenal glands and the ovaries yielded testosterone levels of 20.3 nmol/L and 20.0 nmol/L in the right and the left adrenal veins, respectively, and 17.9 nmol/L and 27.4 nmol/L in the right and left ovaries venous plexus, respectively. Sequencial dexamethasone and ethynyl estradiol suppression test showed a decrease in cortisol level with no change in total testosterone level on dexamethasone while an increase in testosterone from 10.5 nmol/L to 20.1 nmol/L was observed ten days after ethynil estradiol had been associated to dexamethasone. When a gonadotropin-releasing hormone agonist (gonadorelin 3.5 mg i.m.) was administered for 2 months, serum gonadotropins levels decreased to less than 2 IU/L, total testosterone to 3.8 nmol/L and estradiol to less than 36 pmol/L. The patient was submitted to a pelvic exploratory laparotomy and a left salpingo-oophorectomy was performed. A solid and circumscribed ovarian tumor of 1.0 cm in diameter was found. The pathological diagnosis was a Leydig cell tumor with surrounding stromal hyperplasia. These findings may suggest that this tumor was gonadotropin-dependent being indirectly stimulated by ethynil estradiol, through a sensitization of the pituitary gonadotropes and increase in gonadotropin levels and suppressed by a gonadotropin-releasing hormone agonist. PMID:9492110

  2. Atrazine-Mediated Disruption of Steroidogenesis in BLTK1 Murine Leydig Cells.

    PubMed

    Karmaus, Agnes L; Zacharewski, Timothy R

    2015-12-01

    Atrazine (ATR) is a broad-spectrum triazine herbicide that disrupts steroidogenesis resulting in reproductive and developmental toxicity at high doses. Mouse BLTK1 Leydig cells were used as a steroidogenic model to investigate the effects of ATR on testosterone (T) biosynthesis. Induction of steroidogenesis by 3 ng/ml recombinant human chorionic gonadotropin (rhCG) induced intracellular 3',5' cyclic adenosine monophosphate (cAMP) approximately 20-fold and T approximately 3-fold at 4 h. Co-treatment with 300 μM ATR super-induced cAMP levels 100-fold yet antagonized rhCG-mediated induction of T approximately 20% at 4 h. ATR inhibited cAMP-specific phosphodiesterase (cPDE) with an IC50 of ≥98 μM, suggesting cPDE inhibition contributes to the super-induction of cAMP. However, concentrations of up to 3 mM db-cAMP did not antagonize rhCG induction of T levels, suggesting cAMP super-induction alone does not decrease T biosynthesis. Western analysis of cAMP-activated protein kinase A (PKA) target proteins identified ATR-mediated concentration-dependent alterations in phosphorylation including phospho-CREB. These results suggest the cPDE inhibition by ATR and super-induction of cAMP are independent of effects on T levels, and that altered phosphorylation of key steroidogenic regulatory proteins may underlie ATR-mediated disruption of steroidogenesis. PMID:26377646

  3. Bilateral Laparoscopic Gonadectomy in a Patient With Complete Androgen Insensitivity Syndrome and Bilateral Sertoli-Leydig Cell Tumor: A Case Report and Brief Review of the Literature

    PubMed Central

    Asl Zare, Mohammad; Kalantari, Mahmood Reza; Asadpour, Amir Abbas; Kamalati, Ali

    2014-01-01

    Introduction: Complete androgen insensitivity syndrome (previously called testicular feminization) is specified by a 46 XY karyotype and negative sex chromatin, bilateral undescended testes, female genitalia appearance, and lack of mullerian derivatives. Case Presentation: A 28-year-old woman with complete (severe) androgen resistance underwent prophylactic laparoscopic bilateral gonadectomy because of the eventually increased risk of gonadal malignancy. Although the gonads appeared grossly normal, microscopic examination revealed bilateral well differentiated sertoli–leydig cell tumor (SLCT). Discussion: Our Medline search revealed that this is the first reported case of bilateral sertoli–leydig cell tumor (SLCT) in androgen insensitivity syndrome. PMID:25032133

  4. In vitro production of cyclic AMP and steroids from an ovarian Sertoli-Leydig cell tumor. Notes on clinical management.

    PubMed

    Abrahamsson, G; Dahlgren, E; Hahlin, M; Knutson, F; Norström, A; Janson, P O

    1995-04-01

    A 27 year old nulliparous woman with a history of chronic anovulation and signs of virilization with a markedly elevated serum level of testosterone, underwent a laparotomy with peroperative bilateral ovarian vein catheterization and bilateral bisection of both ovaries. A solid, 1.5 cm, well delimited tumor located centrally in the right ovary, was excised. Testosterone levels in ovarian venous blood from the tumor bearing side, were 88.4 nmol/l and from the contralateral ovary 3.9 nmol/l. Histopathological examination showed a Sertoli-Leydig cell tumor which was radically extirpated. Postoperatively, the serum levels of androgen normalized, the woman had regular cycles, became pregnant and delivered a normal female baby. Pieces of tumor tissue were incubated for 2 h, with and without addition of gonadotropins and adrenocorticotropic hormone (ACTH). Human chorionic gonadotropin (CG), follicle stimulating hormone (FSH) and adrenocorticotropic hormone (ACTH) caused significant increases in cyclic monophosphate (cAMP) production in tumor tissue in vitro, as compared to controls. Furthermore, ACTH also significantly stimulated 17 beta-estradiol production. In tumor cells cultured for 48 h, FSH slightly, but not significantly, increased the production of progesterone. In the cell culture, [3H]-thymidine incorporation into deoxyribonucleic acid (DNA) was stimulated by IGF1 alpha but not by hCG and FSH. It is concluded that Sertoli-Leydig cell tumors may be sensitive to gonadotropins and ACTH and that their small size, solid shape and intra-ovarian localization can cause diagnostic difficulties. PMID:7732806

  5. Intracellular redistribution of SCP2 in Leydig cells after hormonal stimulation may contribute to increased pregnenolone production.

    PubMed

    van Noort, M; Rommerts, F F; van Amerongen, A; Wirtz, K W

    1988-07-15

    Sterol carrier protein2 (SCP2) also designated non specific lipid transfer protein (nsL-TP), added to tumour Leydig cell mitochondria as a pure compound or in cytosolic preparations, stimulates pregnenolone production two- to three-fold. This stimulation can be abolished by addition of anti rat SCP2 but not by preimmune IgG-antibodies. SCP2- levels in the cytosol are increased in less than two minutes after addition of lutropin (LH). This increased SCP2 level may contribute to stimulation of steroid production in intact cells. After hormonal stimulation the subcellular distribution of SCP2 changes. A two-fold increase of SCP2- levels in the supernatant fraction and four-fold decrease in extracts of the particulate fraction was observed 30 min after stimulation of tumour Leydig cells with LH and subsequent fractionation. This apparent shift of SCP2 can be explained by an altered association with membranes or a true relocation of the protein from the particulate to the supernatant fractions under the influence of the hormone. PMID:3395346

  6. Different processing of LH/hCG receptors in cultured rat luteal cells and murine Leydig tumor cells (MLTC-1)

    SciTech Connect

    Kellokumpu, S.

    1987-02-01

    The metabolic fate of LH/hCG receptors after exposure to human chorionic gonadotropin (hCG) was examined in cultured rat luteal cells and murine Leydig tumor cells (MLTC-1). Kinetic studies performed after pulse-labelling of the cells with (/sup 125/I)hCG indicated that the bound hormone was lost much more rapidly from the tumor cells than from the luteal cells. The tumor cells were also found to internalize and degrade the hormone more effectively than the luteal cells. Chemical cross-linking and analyses by SDS-PAGE of this material revealed that both cell types also released, in addition to intact hCG, two previously characterized receptor fragment-(/sup 125/I)hCG complexes (M/sub r/ 96,000 and 74,000) into the medium, although their amount was negligible in MLTC-1 cells. Possibly due to rapid discharge of the ligand from its receptor, no similar complexes could be detected inside the MLTC-1 cells, suggesting that they were released directly from the cell surface. However, the M/sub r/ 74,000 complex was observed inside MLTC-1 cells if chloroquine, a lysosomotropic agent, was present during the incubations. This suggests that the internalized receptor also becomes degraded, at least when complexed to hCG. The results thus provide evidence that there exist two different mechanisms for proteolytic processing of LH/hCG receptors in these target cells. In tumor cells, the degradation seems to occur almost exclusively intracellularly, whereas in luteal cells a substantial portion of the receptors is also degraded at the cell surface.

  7. Arachidonic acid is involved in the regulation of hCG induced steroidogenesis in rat Leydig cells

    SciTech Connect

    Didolkar, A.K.; Sundaram, K.

    1987-07-27

    Phospholipase C (PLC), an enzyme involved in the hydrolysis of membrane phospholipid- phosphatidylinositol-bisphosphate to insositol triphosphate and diacylglycerol, and Phorbol 12, myristate 13, acetate (PMA) could significantly stimulate testosterone (T) secretion from Leydig cells. Arachidonic acid (AA) stimulated T secretion by about 2 fold. The steroidogenic effect of PLC and AA was biphasic. At low concentrations both PLC and AA augmented hCG induced T secretion, while at higher concentrations they inhibited steroid production. AA also had a biphasic effect on hCG induced cyclic AMP secretion. 5,8,11,14 Eicosatetrayenoic acid, a general inhibitor of AA metabolism, and Nordihydroguaiaretic acid, an inhibitor of the lipoxygenase pathway of AA metabolism, inhibited hCG induced T secretion while indomethacin, an inhibitor of cyclo-oxygenase pathway, had no effect on hCG induced T secretion. The authors conclude from these data that AA plays a role in the regulation of hCG induced steroidogenic responses in rat Leydig cells and that the metabolite(s) of AA that are involved are not cyclo-oxygenase products. 28 references, 4 figures, 2 tables.

  8. Characterization of lipid droplets in steroidogenic MLTC-1 Leydig cells: Protein profiles and the morphological change induced by hormone stimulation.

    PubMed

    Yamaguchi, Tomohiro; Fujikawa, Noriyuki; Nimura, Satomi; Tokuoka, Yutaro; Tsuda, Sonoka; Aiuchi, Toshihiro; Kato, Rina; Obama, Takashi; Itabe, Hiroyuki

    2015-10-01

    Lipid droplets (LDs) are functional subcellular organelles involved in multiple intracellular processes. LDs are found in nearly all types of eukaryotic cells, but their properties are highly variable in different types of tissues. Steroidogenic cells synthesize steroid hormones de novo from the cholesterol deposited in cytosolic LDs. However, the roles of LD proteins in steroidogenesis under pituitary hormone stimulation have not been well elucidated. The protein profile of isolated LDs from the mouse Leydig tumor cell line MLTC-1 was distinct from that of hepatic cells or macrophages. By proteomic analysis of the components using mass spectrometry, two enzymes for steroidogenesis, 3β-hydroxysteroid dehydrogenase type 1 (3βHSD1) and 17 β-hydroxysteroid dehydrogenase type 11 (17βHSD11), were identified in two strong bands in the LD fractions. The LD fraction of MLTC-1 cells also included CYP11A1 and CYP17, suggesting that the LDs contain all the enzymes needed for testosterone synthesis. The steroidogenesis in Leydig cells is activated by luteinizing hormone through a PKA-dependent pathway. Stimulation of MLTC-1 cells with luteinizing hormone or 8-bromo-cAMP caused drastic changes in the morphology of the LDs in the MLTC-1 cells. Upon stimulation, large perinuclear LDs are turned into much smaller LDs and dispersed throughout the cytosol. These results raise the possibility that LDs are involved in a regulatory pathway of steroidogenesis, not just by serving as a storage depot for cholesterol esters, but also by providing enzymes and generating sites for enzymatic activity. PMID:26143378

  9. Observation of Organelles in Leydig Cells by Contact Soft X-Ray Microscopy with a Laser Plasma X-Ray Source

    NASA Astrophysics Data System (ADS)

    Kado, M.; Ishino, M.; Tamotsu, S.; Yasuda, K.; Kishimoto, M.; Nishikino, M.; Kinjo, Y.; Shinohara, K.

    2011-09-01

    We observed the same biological specimens for comparison of the images by contact soft x-ray microscopy with a laser plasma x-ray source with those by confocal laser microscopy. Images of wet Leydig cells were directly comparable for organelles and showed that actin filaments and mitochondria were clearly identified in the soft x-ray images.

  10. Steroidogenic differential effects in neonatal porcine Leydig cells exposed to persistent organic pollutants derived from cod liver oil.

    PubMed

    Granum, Cesilie; Anchersen, Sara; Karlsson, Camilla; Berg, Vidar; Olsaker, Ingrid; Verhaegen, Steven; Ropstad, Erik

    2015-11-01

    Seafood products, including fish and fish oils, are major sources of persistent organic pollutants (POPs) which may cause endocrine disruption related to reproductive dysfunction in males. Primary porcine neonatal Leydig cells were exposed to three extracts of POPs obtained from different stages in production of cod liver oil dietary supplement, in the absence and presence of luteinizing hormone (LH). No reduced viability was observed and all POP extracts showed increased testosterone and estradiol levels in unstimulated cells and decreased testosterone and estradiol secretion in LH-stimulated cells. A decrease in central steriodogenic genes including STAR, CYP11A1, HSD3B and CYP17A1 was obtained in both culture conditions with all POP extracts. We implicate both small differences in composition and concentration of compounds as well as "old" POPs to be important for the observed steroidogenic effects. PMID:26055946

  11. Gonadotropin stimulation of cyclic adenosine monophosphate and testosterone production without detectable high-affinity binding sites in purified Leydig cells from rat testis

    SciTech Connect

    Browne, E.S.; Bhalla, V.K. )

    1991-02-01

    Rat testicular interstitial cells were separated by three different gradient-density procedures and, with each, two biochemically and morphologically distinct cell fractions were isolated. The lighter density cells in fraction-I bound iodine 125-labeled human chorionic gonadotropin (hCG) with high-affinity (apparent equilibrium dissociation constant, Kd, approximately 10{sup {minus} 10} M) without producing either cyclic adenosine monophosphate or testosterone in response to hormone action. The heavier-density cells displayed morphologic features typical of Leydig cells and produced cyclic adenosine monophosphate and testosterone in the presence of hCG without detectable {sup 125}I-labeled hCG high-affinity binding. These cell fractions were further characterized by studies using deglycosylated hCG, a known antagonist to hCG action. Cell concentration-dependent studies with purified Leydig cells revealed that maximal testosterone production was achieved when lower cell concentrations (0.5 x 10(6) cells/250 microliters) were used for in vitro hCG stimulation assays. Under these conditions, the {sup 125}I-labeled hCG binding was barely detectable (2.24 fmol; 2,698 sites/cell). Furthermore, these studies revealed that the hCG-specific binding in Leydig cells is overestimated by the classic method for nonspecific binding correction using excess unlabeled hormone. An alternate method is presented.

  12. Structural bisphenol analogues differentially target steroidogenesis in murine MA-10 Leydig cells as well as the glucocorticoid receptor.

    PubMed

    Roelofs, Maarke J E; van den Berg, Martin; Bovee, Toine F H; Piersma, Aldert H; van Duursen, Majorie B M

    2015-03-01

    Although much information on the endocrine activity of bisphenol A (BPA) is available, a proper human hazard assessment of analogues that are believed to have a less harmful toxicity profile is lacking. Here the possible effects of BPA, bisphenol F (BPF), bisphenol S (BPS), as well as the brominated structural analogue and widely used flame retardant tetrabromobisphenol A (TBBPA) on human glucocorticoid and androgen receptor (GR and AR) activation were assessed. BPA, BPF, and TBBPA showed clear GR and AR antagonism with IC50 values of 67 μM, 60 μM, and 22 nM for GR, and 39 μM, 20 μM, and 982 nM for AR, respectively, whereas BPS did not affect receptor activity. In addition, murine MA-10 Leydig cells exposed to the bisphenol analogues were assessed for changes in secreted steroid hormone levels. Testicular steroidogenesis was altered by all bisphenol analogues tested. TBBPA effects were more directed towards the male end products and induced testosterone synthesis, while BPF and BPS predominantly increased the levels of progestagens that are formed in the beginning of the steroidogenic pathway. The MA-10 Leydig cell assay shows added value over the widely used H295R steroidogenesis assay because of its fetal-like characteristics and specificity for the physiologically more relevant testicular Δ4 steroidogenic pathway. Therefore, adding an in vitro assay covering fetal testicular steroidogenesis, such as the MA-10 cell line, to the panel of tests used to screen potential endocrine disruptors, is highly recommendable. PMID:25576683

  13. Cordycepin induced MA-10 mouse Leydig tumor cell apoptosis by regulating p38 MAPKs and PI3K/AKT signaling pathways

    PubMed Central

    Pan, Bo-Syong; Wang, Yang-Kao; Lai, Meng-Shao; Mu, Yi-Fen; Huang, Bu-Miin

    2015-01-01

    The p38 MAPKs play important roles in the regulation of balance between cell survival and cell death on the development of various cancers. However, the roles of p38 MAPKs regulating apoptotic effects on Leydig tumor cells remain unclear. In the present study, we showed that cordycepin (3′-deoxyadenosine) selectively induced apoptosis in MA-10 mouse Leydig tumor cells through regulating the p38 MAPK and PI3K/AKT signaling pathways. Cordycepin reduced viability in MA-10, TM4, and NT2/D1 cells, but not cause cell death of primary mouse Leydig cells on moderate concentration. Cordycepin increased reactive oxygen species (ROS) levels, which is associated with the induction of apoptosis as characterized by positive Annexin V binding, activation of caspase-3, and cleavage of PARP. Inhibition of p38 MAPKs activity by SB203580 significantly prevented cordycepin-induced apoptosis in MA-10 cells. Co-treatment with wortmannin or the autophagy inhibitor 3-methyladenine (3-MA) elevated levels of apoptosis in cordycepin-treated MA-10 cells. Moreover, cordycepin activated p53, p21 and TGFß; and downregulated CDK2. The antitumour activity of cordycepin-treated MA-10 cells was significantly distinct in severe combined immunodeficiency (SCID) mice in vivo. These results suggested that cordycein is a highly selective treatment to induce MA-10 cells apoptosis via p38 MAPKs signaling. PMID:26303320

  14. Apoptotic effect of cordycepin combined with cisplatin and/or paclitaxel on MA-10 mouse Leydig tumor cells

    PubMed Central

    Kang, Fu-Chi; Chen, Pei-Jung; Pan, Bo-Syong; Lai, Meng-Shao; Chen, Yung-Chia; Huang, Bu-Miin

    2015-01-01

    Background Chemotherapy is not limited to a single treatment, and the evidence demonstrates that different drug combinations can have positive results in patients. In this study, we sought to determine whether cordycepin combined with cisplatin and/or paclitaxel would have an additive effective on inducing apoptosis in mouse Leydig tumor cells, and the mechanisms were also briefly examined. Methods The additive effects of cordycepin combined with cisplatin and/or paclitaxel on apoptosis in MA-10 cells were investigated by monitoring changes in morphological characteristics and examining cell viability, flow cytometry assays, and Western blot analyses. Results Combination of cordycepin plus cisplatin and/or paclitaxel for 12 and 24 hours induced apoptotic features in MA-10 cells. The MTT assay showed that the combination treatment reduced the viability of MA-10 cells in a dose-dependent manner, with additive effects. Cell cycle analysis showed that combination treatment significantly increased subG1 phase cell numbers in MA-10 cells, indicating apoptosis. Moreover, cordycepin plus cisplatin and/or paclitaxel significantly induced cleavage of caspase-8, caspase-9, caspase-3, and poly ADP-ribose polymerase, and phosphorylation of c-Jun NH2-terminal kinase, extracellular signal-regulated kinase, p38, and p53 proteins in MA-10 cells. Conclusion Cordycepin plus cisplatin and/or paclitaxel can have an additive effect on apoptosis in MA-10 cells, with activation of caspase, mitogen-activated protein kinase, and p53 signal pathways. PMID:26366090

  15. Response to the Svingen Comments on Li et al. Effects of in Utero Exposure to Dicyclohexyl Phthalate on Rat Fetal Leydig Cells. Int. J. Environ. Res. Public Health, 2016, 13, 246.

    PubMed

    Li, Xiaoheng; Chen, Xiaomin; Hu, Guoxin; Li, Linxi; Su, Huina; Wang, Yiyan; Chen, Dongxin; Zhu, Qiqi; Li, Chao; Li, Junwei; Wang, Mingcang; Lian, Qingquan; Ge, Ren-Shan

    2016-01-01

    Referring to the comments of Svingen [1] on our latest publication about Effects of in utero Exposure to Dicyclohexyl Phthalate on Rat Fetal Leydig Cells [2], we would like to give some comments.[...]. PMID:27231929

  16. Light and electron microscopical observations on the Leydig cells of the scrotal and abdominal testes of naturally unilateral cryptorchid West African dwarf goats.

    PubMed Central

    Ezeasor, D N

    1985-01-01

    The structure of interstitial cells of Leydig in the scrotal and abdominal testes of adult West African dwarf goats was studied utilising light and electron microscopy. The Leydig cells in both testes were scattered singly, in cords or clusters in the intertubular connective tissue in close proximity to vascular elements. The intertubular connective tissue in the abdominal testes was however much wider because of the hypoplasia of the seminiferous tubules. While the cells of the scrotal testes exhibited non-granular, pale staining cytoplasm, those of the abdominal testes were darkly staining and the majority contained coarse intracytoplasmic osmiophilic granules Interspersed amongst these cells were adipose cells occasionally distributed overall. With the electron microscope, it was found that agranular endoplasmic reticulum, Golgi apparatus and mitochondria were more prominently developed in the scrotal testes. In marked contrast, there were numerous lipid droplets in the cytoplasm of the Leydig cells in the abdominal testes. Furthermore, the cytoplasm of several of these cells showed evidence of degeneration. It is concluded that, contrary to observations in the experimentally induced condition, abdominal retention of testes in natural unilateral cryptorchidism induces alterations in the light microscopical and ultrastructural features of the Leydig cells of West African dwarf goats, changes which possibly can be ascribed to the chronic decline in testicular blood flow and the elevated temperature of the abdominal environment. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 PMID:2867081

  17. Arachidonic acid release from rat Leydig cells: the involvement of G protein, phospholipase A2 and regulation of cAMP production.

    PubMed

    Ronco, A M; Moraga, P F; Llanos, M N

    2002-01-01

    We have previously demonstrated that the release of arachidonic acid (AA) from human chorionic gonadotropin (hCG)-stimulated Leydig cells occurs in a dose- and time-dependent manner. In addition, the amount of AA released was dependent on the hormone-receptor interaction and the concentration of LH-hCG binding sites on the cell surface. The present study was conducted to evaluate the involvement of phospholipase A(2) (PLA(2)) and G proteins in AA release from hormonally stimulated rat Leydig cells, and the possible role of this fatty acid in cAMP production. Cells were first prelabelled with [(14)C]AA to incorporate the fatty acid into cell phospholipids, and then treated in different ways to evaluate AA release. hCG (25 mIU) increased the release of AA to 180+/-12% when compared with AA released from control cells, arbitrarily set as 100%. Mepacrine and parabromophenacyl bromide (pBpB), two PLA(2) inhibitors, decreased the hormone-stimulated AA release to 85+/-9 and 70+/-24% respectively. Conversely, melittin, a PLA(2) stimulator, increased the release of AA up to 200% over control. The inhibitory effect of mepacrine on the release of AA was evident in hCG-treated Leydig cells, but not in the melittin-treated cells. To determine if the release of AA was also mediated through a G protein, cells were first permeabilized and subsequently treated with pertussis toxin or GTPgammaS, a non-hydrolyzable analog of GTP. Results demonstrate that GTPgammaS was able to induce a similar level of the release of AA as hCG. In addition, pertussis toxin completely abolished the stimulatory effect of hCG on the release of AA, indicating that a member of the G(i) family was involved in the hCG-dependent release of AA. Cells treated with PLA(2) inhibitors did not modify cAMP production, but exogenously added AA significantly reduced cAMP production from hCG-treated Leydig cells, in a manner dependent on the concentration of AA and hCG. Results presented here suggest an involvement of

  18. Tetrahydroisoquinoline alkaloids mimic direct but not receptor-mediated inhibitory effects of estrogens and phytoestrogens on testicular endocrine function. Possible significance for Leydig cell insufficiency in alcohol addiction

    SciTech Connect

    Stammel, W.; Thomas, H. ); Staib, W.; Kuehn-Velten, W.K. )

    1991-01-01

    Possible effects of various tetrahydroisoquinolines (TIQs) on rat testicular endocrine function were tested in vitro in order to prove whether these compounds may be mediators of the development of Leydig cell insufficiency. TIQ effects on different levels of regulation of testis function were compared in vitro with estrogen effects, since both classes of compounds have structural similarities. Gonadotropin-stimulated testosterone production by testicular Leydig cells was inhibited by tetrahydropapaveroline and isosalsoline, the IC{sub 50} values being comparable to those of estradiol, 2-hydroxyestradiol, and the phytoestrogens, coumestrol and genistein; salsolinol and salsoline were less effective, and salsolidine was ineffective. None of these TIQs interacted significantly with testicular estrogen receptor as analyzed by estradiol displacement. However, tetrahydropapaveroline, isosalsoline and salsolinol competitively inhibited substrate binding to cytochrome P45OXVII, with similar efficiency as the estrogens did; salsoline and salsolidine were again much less effective.

  19. Observation of Actin Filaments in Leydig Cells with a Contact-type Soft X-ray Microscope with Laser Plasma X-ray Source

    NASA Astrophysics Data System (ADS)

    Kado, Masataka; Ishino, Masahiko; Tamotsu, Satoshi; Yasuda, Keiko; Kishimoto, Maki; Nishikino, Masaharu; Kinjo, Yasuhito; Shinohara, Kunio

    Actin filaments in Leydig cells from mouse testes have been observed with a contact-type soft x-ray microscope with laser plasma x-ray source. The Leydig cells were fixed with paraformaldehyde, stained with Phalloidin, and observed with a confocal laser microscope prior to the observation with x-ray microscope. Obtained images by both of the confocal laser microscopy and the x-ray microscopy were directly compared and revealed that not only position of actin filaments but also the shapes can be identified each other. The actin filaments in the x-ray images were clearly recognized and their structures were obtained in more detail compared to those in the confocal laser microscope images.

  20. Structural organization of the porcine and human genes coding for a leydig cell-specific insulin-like peptide (LEY I-L) and chromosomal localization of the human gene (INSL3)

    SciTech Connect

    Burkhardt E.; Adham, I.M.; Brosig, B.; Gastmann, A.; Engel, W. ); Mattei, M.G. )

    1994-03-01

    Leydig insulin-like protein (LEY I-L) is a member of the insulin-like hormone superfamily. The LEY I-L gene (designated INSL3) is expressed exclusively in prenatal and postnatal Leydig cells. The authors report here the cloning and nucleotide sequence of porcine and human LEY I-L genes including the 5[prime] regions. Both genes consist of two exons and one intron. The organization of the LEY I-L gene is similar to that of insulin and relaxin. The transcription start site in the porcine and human LEY I-L gene is localized 13 and 14 bp upstream of the translation start site, respectively. Alignment of the 5[prime] flanking regions of both genes reveals that the first 107 nucleotides upstream of the transcription start site exhibit an overall sequence similarity of 80%. This conserved region contains a consensus TATAA box, a CAAT-like element (GAAT), and a consensus SP1 sequence (GGGCGG) at equivalent positions in both genes and therefore may play a role in regulation of expression of the LEY I-L gene. The porcine and human genome contains a single copy of the LEY I-L gene. By in situ hybridization, the human gene was assigned to bands p13.2-p12 of the short arm of chromosome 19. 25 refs., 6 figs.

  1. TPP and TCEP induce oxidative stress and alter steroidogenesis in TM3 Leydig cells.

    PubMed

    Chen, Guanliang; Zhang, Songbin; Jin, Yuanxiang; Wu, Yan; Liu, Ling; Qian, Haifeng; Fu, Zhengwei

    2015-11-01

    Effects of triphenyl phosphate (TPP) and tris-(2-chloroethyl) phosphate (TCEP) exposure on induction of oxidative stress and endocrine disruption were investigated in TM3 cells. After 24h exposure, cell growth declined and morphology changed in TPP and TCEP treated groups with high dosages. Significant increases in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione S-transferase (GST) activities and their respective gene expressions in a dose-dependent and/or time-dependent manner in TPP or TCEP groups. Moreover, the expression of main genes related to testosterone (T) synthesis including cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), cytochrome P450 17α-hydroxysteroid dehydrogenase (P450-17α), 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β-HSD) were dramatically reduced by TPP and TCEP treatments, especially with the high dosage for 24h. TPP and TCEP treatments for 24h caused significant decreases in T levels in the medium. Furthermore, co-treatments of hCG with TPP or TCEP could inhibit hCG-induced changes in the expression of P450scc, P450-17α and 17β-HSD and T levels. Taken together, TPP and TCEP could induce oxidative stress and endocrine disruption in TM3 cells. PMID:26049154

  2. Steroidogenesis in MA-10 Mouse Leydig Cells Is Altered via Fatty Acid Import into the Mitochondria1

    PubMed Central

    Rone, Malena B.; Midzak, Andrew S.; Martinez-Arguelles, Daniel B.; Fan, Jinjiang; Ye, Xiaoying; Blonder, Josip; Papadopoulos, Vassilios

    2014-01-01

    ABSTRACT Mitochondria are home to many cellular processes, including oxidative phosphorylation and fatty acid metabolism, and in steroid-synthesizing cells, they are involved in cholesterol import and metabolism, which is the initiating step in steroidogenesis. The formation of macromolecular protein complexes aids in the regulation and efficiency of these mitochondrial functions, though because of their dynamic nature, they are hard to identify. To overcome this problem, we used Blue-Native PAGE with whole-gel mass spectrometry on isolated mitochondria from control and hormone-treated MA-10 mouse tumor Leydig cells. The presence of multiple mitochondrial protein complexes was shown. Although these were qualitatively similar under control and human chorionic gonadotropin (hCG)-stimulated conditions, quantitative differences in the components of the complexes emerged after hCG treatment. A prominent decrease was observed with proteins involved in fatty acid import into the mitochondria, implying that mitochondrial beta-oxidation is not essential for steroidogenesis. To confirm this observation, we inhibited fatty acid import utilizing the CPT1a inhibitor etomoxir, resulting in increased steroid production. Conversely, stimulation of mitochondrial beta-oxidation with metformin resulted in a dose-dependent reduction in steroidogenesis. These changes were accompanied by changes in mitochondrial respiration and in the lactic acid formed during glycolysis. Taken together, these results suggest that upon hormonal stimulation, mitochondria efficiently import cholesterol for steroid production at the expense of other lipids necessary for energy production, specifically fatty acids required for beta-oxidation. PMID:25210128

  3. Nuclear Morphometric Analysis of Leydig Cells of Male Pubertal Rats Exposed In Utero to Di(n-butyl) Phthalate

    PubMed Central

    Wakui, Shin; Motohashi, Masaya; Satoh, Takemi; Shirai, Masaru; Mutou, Tomoko; Takahashi, Hiroyuki; Wempe, Michael F.; Endou, Hitoshi; Inomata, Tomoo; Asari, Masao

    2013-01-01

    We recently reported that prenatal rat exposure to di(n-butyl) phthalate (DBP) induced Leydig cell (LC) hyperplasia after nine weeks (wks) of age, yet the number of LCs was similar to that of the vehicle group until seven weeks. Nuclear pleomorphism of hyperplastic LCs is common and is considered to be continuous progressive degeneration. Thus, computer-assisted image cell nuclear analysis of LCs was performed on 5- and 7-wk-old Sprague-Dawley (SD) rats whose dams had been administered DBP (i.g.) at 100 mg/kg/day or vehicle (corn oil) on gestation day 12 to 21. The results of the 5-wk-old DBP group were similar to those of the vehicle group; LC nuclei of the 7-wk-old DBP group showed normal ploidy and similar amounts of DNA. However, the size, elongation and peripheral chromatin aggregation parameters were significantly higher, and the reticular chromatin distribution and isolated chromatin aggregation parameters were significantly lower compared with the vehicle group. The present study quantitatively demonstrated nuclear morphological alterations in rat LCs at 7 wks old (puberty) due to the prenatal DBP administration before apparent LC hyperplasia developed. PMID:24526819

  4. Effect of protein-synthesis inhibitors on testosterone production in rat testis interstitial tissue and Leydig-cell preparations.

    PubMed Central

    Cooke, B A; Janszen, F H; Clotscher, W F; van der Molen, H J

    1975-01-01

    Luteinizing-hormone-stimulated testosterone biosynthesis was inhibited by cycloheximide during incubation of rat testis intersitial tissue in vitro and also by puromycin and cycloheximide during incubation of Leydig-cell preparations, but not by chloramphenicol. These results suggest that a protein regualtor(s) formed by cytoplasmic protein synthesis is involved in steroidogenesis in the rat testis. The specific effect of cycloheximide and puromycin on protein synthesis rather than on other non-specific processes is suggested by the inhibition of protein synthesis and steroidogenesis with different doses of the inhibitors and the lack of effect of cycloheximide on luteinizing-hormone-induced adenosine 3':5'-cyclic monophosphate production. Stimulation of testosterone production by luteinizing hormone during superfusion of interstitial tissue was detectable within 10-20 min and reached a maximum of 120 min, and thereafter slowly decreased. Cycloheximide added at maximum steroid production caused a rapid decrease in testosterone synthesis which followed first-order kinetics (half-life 13 min), thus indicating that the protein regulator(s) has a short half-life. No effect of cycloheximide, puromycin or chloramphenicol on testosterone production in the absence of added luteinizing hormone was found, suggesting that the basal production of testosterone is independent of protein synthesis. PMID:174545

  5. A new variant in signal peptide of the human luteinizing hormone receptor (LHCGR) affects receptor biogenesis causing leydig cell hypoplasia.

    PubMed

    Vezzoli, Valeria; Duminuco, Paolo; Vottero, Alessandra; Kleinau, Gunnar; Schülein, Ralf; Minari, Roberta; Bassi, Ivan; Bernasconi, Sergio; Persani, Luca; Bonomi, Marco

    2015-11-01

    The human luteinizing hormone/chorionic gonadotropin receptor (LHCGR) plays a fundamental role in male and female reproduction. In males, loss-of-function mutations in LHCGR have been associated with distinct degrees of impairment in pre- and postnatal testosterone secretion resulting in a variable phenotypic spectrum, classified as Leydig cell hypoplasia (LCH) type 1 (complete LH resistance and disorder of sex differentiation) and type 2 (partial LH resistance with impaired masculinization and fertility). Here, we report the case of an adolescent who came to the pediatric endocrinologist at the age of 12 years old for micropenis and cryptorchidism. Testis biopsy showed profound LCH and absent germinal line elements (Sertoli-only syndrome). The sequence analysis of the LHCGR gene showed the presence of a compound heterozygosity, being one variation, c.1847C>A p.S616Y, already described in association to Hypergonadotropic Hypogonadism, and the other, c.29 C>T p.L10P, a new identified variant in the putative signal peptide (SP) of LHCGR. Functional and structural studies provide first evidence that LHCGR have a functional and cleavable SP required for receptor biogenesis. Moreover, we demonstrate the pathogenic role of the novel p.L10P allelic variant, which has to be considered a loss-of-function mutation significantly contributing, in compound heterozygosity with p.S616Y, to the LCH type 2 observed in our patient. PMID:26246498

  6. Leydig cell number and sperm production decrease induced by chronic ametryn exposure: a negative impact on animal reproductive health.

    PubMed

    Dantas, T A; Cancian, G; Neodini, D N R; Mano, D R S; Capucho, C; Predes, F S; Pulz, R Barbieri; Pigoso, A A; Dolder, H; Severi-Aguiar, G D C

    2015-06-01

    Ametryn is an herbicide used to control broadleaf and grass weeds and its acute and chronic toxicity is expected to be low. Since toxicological data on ametryn is scarce, the aim of this study was to evaluate rat reproductive toxicity. Thirty-six adult male Wistar rats (90 days) were divided into three groups: Co (control) and T1 and T2 exposed to 15 and 30 mg/kg/day of ametryn, respectively, for 56 days. Testicular analysis demonstrated that ametryn decreased sperm number per testis, daily sperm production, and Leydig cell number in both treated groups, although little perceptible morphological change has been observed in seminiferous tubule structure. Lipid peroxidation was higher in group T2, catalase activity decreased in T1 group, superoxide dismutase activity diminished, and a smaller number of sulphydryl groups of total proteins were verified in both exposed groups, suggesting oxidative stress. These results showed negative ametryn influence on the testes and can compromise animal reproductive performance and survival. PMID:25561257

  7. Gonadotropin-regulated Testicular RNA Helicase (GRTH/DDX25), a Negative Regulator of Luteinizing/Chorionic Gonadotropin Hormone-induced Steroidogenesis in Leydig Cells

    PubMed Central

    Fukushima, Masato; Villar, Joaquin; Tsai-Morris, Chon-Hwa; Dufau, Maria L.

    2011-01-01

    Gonadotropin-regulated testicular RNA helicase (GRTH/DDX25) is a testis-specific gonadotropin-regulated RNA helicase that is present in Leydig cells (LCs) and germ cells and is essential for spermatid development and completion of spermatogenesis. Normal basal levels of testosterone in serum and LCs were observed in GRTH null (GRTH−/−) mice. However, testosterone production was enhanced in LCs of GRTH−/− mice compared with WT mice by both in vivo and in vitro human chorionic gonadotropin stimulation. LCs of GRTH−/− mice had swollen mitochondria with a significantly increased cholesterol content in the inner mitochondrial membrane. Basal protein levels of SREBP2, HMG-CoA reductase, and steroidogenic acute regulatory protein (StAR; a protein that transports cholesterol to the inner mitochondrial membrane) were markedly increased in LCs of GRTH−/− mice compared with WT mice. Gonadotropin stimulation caused an increase in StAR mRNA levels and protein expression in GRTH−/− mice versus WT mice, with no further increase in SREBP2 and down-regulation of HMG-CoA reductase protein. The half-life of StAR mRNA was significantly increased in GRTH−/− mice. Moreover, association of StAR mRNA with GRTH protein was observed in WT mice. Human chorionic gonadotropin increased GRTH gene expression and its associated StAR protein at cytoplasmic sites. Taken together, these findings indicate that, through its negative role in StAR message stability, GRTH regulates cholesterol availability at the mitochondrial level. The finding of an inhibitory action of GRTH associated with gonadotropin-mediated steroidogenesis has provided insights into a novel negative autocrine molecular control mechanism of this helicase in the regulation of steroid production in the male. PMID:21719703

  8. Intratesticular alpha1-adrenergic receptors mediate stress-disturbed transcription of steroidogenic stimulator NUR77 as well as steroidogenic repressors DAX1 and ARR19 in Leydig cells of adult rats.

    PubMed

    Stojkov-Mimic, Natasa J; Bjelic, Maja M; Radovic, Sava M; Mihajlovic, Aleksandar I; Sokanovic, Srdjan J; Baburski, Aleksandar Z; Janjic, Marija M; Kostic, Tatjana S; Andric, Silvana A

    2015-09-01

    The aim of the present study was to define the role of testicular α1-adrenergic receptors (α1-ADRs) in stress-triggered adaptation of testosterone-producing Leydig cells of adult rats. Results showed that in vivo blockade of testicular α1-ADRs prevented partial recovery of circulating androgen levels registered after 10× repeated immobilization stress (10 × IMO). Moreover, α1-ADR-blockade diminished 10 × IMO-triggered recovery of Leydig cell androgen production, and abolished mitochondrial membrane potential recovery. In the same cells, 10 × IMO-induced increase in Star transcript was abolished, Lhcgr transcript decreased, while transcription of other steroidogenic proteins was not changed. α1-ADR-blockade recovered stress-induced decrease of Nur77, one of the main steroidogenic stimulator, while significantly reduced 10 × IMO-increased in the transcription of the main steroidogenic repressors, Arr19 and Dax1. In vitro experiments revealed an adrenaline-induced α1-ADR-mediated decrease in Nur77 transcription in Leydig cells. Adrenaline-induced increase of repressor Dax1 also involves ADRs in Leydig cells. Accordingly, α1-ADRs participate in some of the stress-triggered effects on the steroidogenic machinery of Leydig cells. PMID:26003139

  9. Prepubertal Di-n-Butyl Phthalate Exposure Alters Sertoli and Leydig Cell Function and Lowers Bone Density in Adult Male Mice.

    PubMed

    Bielanowicz, Amanda; Johnson, Rachelle W; Goh, Hoey; Moody, Sarah C; Poulton, Ingrid J; Croce, Nic; Loveland, Kate L; Hedger, Mark P; Sims, Natalie A; Itman, Catherine

    2016-07-01

    Phthalate exposure impairs testis development and function; however, whether phthalates affect nonreproductive functions is not well understood. To investigate this, C57BL/6J mice were fed 1-500 mg di-n-butyl phthalate (DBP) in corn oil, or vehicle only, daily from 4 to 14 days, after which tissues were collected (prepubertal study). Another group was fed 1-500 mg/kg·d DBP from 4 to 21 days and then maintained untreated until 8 weeks for determination of adult consequences of prepubertal exposure. Bones were assessed by microcomputed tomography and dual-energy X-ray absorptiometry and T by RIA. DBP exposure decreased prepubertal femur length, marrow volume, and mean moment of inertia. Adult animals exposed prepubertally to low DBP doses had lower bone mineral content and bone mineral density and less lean tissue mass than vehicle-treated animals. Altered dynamics of the emerging Leydig population were found in 14-day-old animals fed 100-500 mg/kg·d DBP. Adult mice had variable testicular T and serum T and LH concentrations after prepubertal exposure and a dose-dependent reduction in cytochrome p450, family 11, subfamily A, polypeptide 1. Insulin-like 3 was detected in Sertoli cells of adult mice administered the highest dose of 500 mg/kg·d DBP prepubertally, a finding supported by the induction of insulin-like 3 expression in TM4 cells exposed to 50 μM, but not 5 μM, DBP. We propose that low-dose DBP exposure is detrimental to bone but that normal bone mineral density/bone mineral content after high-dose DBP exposure reflects changes in testicular somatic cells that confer protection to bones. These findings will fuel concerns that low-dose DBP exposure impacts health beyond the reproductive axis. PMID:27058814

  10. Sterol Carrier Protein-2, a Nonspecific Lipid-Transfer Protein, in Intracellular Cholesterol Trafficking in Testicular Leydig Cells.

    PubMed

    Li, Nancy C; Fan, Jinjiang; Papadopoulos, Vassilios

    2016-01-01

    Sterol carrier protein-2 (SCP2), also called nonspecific lipid-transfer protein, is thought to play a major role in intracellular lipid transport and metabolism, and it has been associated with diseases involving abnormalities in lipid trafficking, such as Zellweger syndrome. The Scp2 gene encodes the 58 kDa sterol carrier protein-x (SCPX) and 15 kDa pro-SCP2 proteins, both of which contain a 13 kDa SCP2 domain in their C-termini. We found that 22-NBD-cholesterol, a fluorescent analog of cholesterol and a preferred SCP2 ligands, was not localized in the peroxisomes. This raises questions about previous reports on the localization of the SCPX and SCP2 proteins and their relationship to peroxisomes and mitochondria in intracellular cholesterol transport. Immunofluorescent staining of cryosections of mouse testis and of MA-10 mouse tumor Leydig cells showed that SCPX and SCP2 are present in both mouse testicular interstitial tissue and in MA-10 cells. Fluorescent fusion proteins of SCPX and SCP2, as well as confocal live-cell imaging, were used to investigate the subcellular targeting of these proteins and the function of the putative mitochondrial targeting sequence. The results showed that SCPX and SCP2 are targeted to the peroxisomes by the C-terminal PTS1 domain, but the putative N-terminal mitochondrial targeting sequence alone is not potent enough to localize SCPX and SCP2 to the mitochondria. Homology modeling and molecular docking studies indicated that the SCP2 domain binds cholesterol, but lacks specificity of the binding and/or transport. These findings further our understanding of the role of SCPX and SCP2 in intracellular cholesterol transport, and present a new point of view on the role of these proteins in cholesterol trafficking. PMID:26901662

  11. Sterol Carrier Protein-2, a Nonspecific Lipid-Transfer Protein, in Intracellular Cholesterol Trafficking in Testicular Leydig Cells

    PubMed Central

    Li, Nancy C.; Fan, Jinjiang; Papadopoulos, Vassilios

    2016-01-01

    Sterol carrier protein-2 (SCP2), also called nonspecific lipid-transfer protein, is thought to play a major role in intracellular lipid transport and metabolism, and it has been associated with diseases involving abnormalities in lipid trafficking, such as Zellweger syndrome. The Scp2 gene encodes the 58 kDa sterol carrier protein-x (SCPX) and 15 kDa pro-SCP2 proteins, both of which contain a 13 kDa SCP2 domain in their C-termini. We found that 22-NBD-cholesterol, a fluorescent analog of cholesterol and a preferred SCP2 ligands, was not localized in the peroxisomes. This raises questions about previous reports on the localization of the SCPX and SCP2 proteins and their relationship to peroxisomes and mitochondria in intracellular cholesterol transport. Immunofluorescent staining of cryosections of mouse testis and of MA-10 mouse tumor Leydig cells showed that SCPX and SCP2 are present in both mouse testicular interstitial tissue and in MA-10 cells. Fluorescent fusion proteins of SCPX and SCP2, as well as confocal live-cell imaging, were used to investigate the subcellular targeting of these proteins and the function of the putative mitochondrial targeting sequence. The results showed that SCPX and SCP2 are targeted to the peroxisomes by the C-terminal PTS1 domain, but the putative N-terminal mitochondrial targeting sequence alone is not potent enough to localize SCPX and SCP2 to the mitochondria. Homology modeling and molecular docking studies indicated that the SCP2 domain binds cholesterol, but lacks specificity of the binding and/or transport. These findings further our understanding of the role of SCPX and SCP2 in intracellular cholesterol transport, and present a new point of view on the role of these proteins in cholesterol trafficking. PMID:26901662

  12. Subcellular distribution of ( sup 3 H)-dexamethasone mesylate binding sites in Leydig cells using electron microscope radioautography

    SciTech Connect

    Stalker, A.; Hermo, L.; Antakly, T. )

    1991-01-01

    The present view is that glucocorticoid hormones bind to their cytoplasmic receptors before reaching their nuclear target sites, which include specific DNA sequences. Although it is believed that cytoplasmic sequestration of steroid receptors and other transcription factors (such as NFKB) may regulate the overall activity of these factors, there is little information on the exact subcellular sites of steroid receptors or even of any other transcription factors. Tritiated (3H)-dexamethasone 21-mesylate (DM) is an affinity label that binds covalently to the glucocorticoid receptor (GR), thereby allowing morphological localization of the receptor at the light and electron microscope levels as well as for quantitative radioautographic (RAG) analysis. After injection of 3H-DM into the testis, a specific radioautographic signal was observed in Leydig cells, which correlated with a high level of immunocytochemically demonstrable GR in these cells at the light-microscope level. To localize the 3H-DM binding sites at the electron microscope (EM) level, the testes of 5 experimental and 3 control adrenalectomized rats were injected directly with 20 microCi 3H-DM; control rats received simultaneously a 25-fold excess of unlabeled dexamethasone; 15 min later, rats were fixed with glutaraldehyde and the tissue was processed for EM RAG analysis combined with quantitative morphometry. The radioautographs showed that the cytosol, nucleus, smooth endoplasmic reticulum (sER), and mitochondria were labeled. Since the cytosol was always adjacent to tubules of the sER, the term sER-rich cytosol was used to represent label over sER networks, which may also represent cytosol labeling due to the limited resolution of the radioautographic technique. Labeling was highest in sER-rich cytosol and mitochondria, at 53% and 31% of the total, respectively.

  13. Evaluation of cytotoxicity and oxidative DNA damaging effects of di(2-ethylhexyl)-phthalate (DEHP) and mono(2-ethylhexyl)-phthalate (MEHP) on MA-10 Leydig cells and protection by selenium

    SciTech Connect

    Erkekoglu, Pinar; Rachidi, Walid; Giray, Belma; Favier, Alain; Hincal, Filiz

    2010-10-01

    Di(2-ethylhexyl)-phthalate (DEHP) is the most abundantly used phthalate derivative, inevitable environmental exposure of which is suspected to contribute to the increasing incidence of testicular dysgenesis syndrome in humans. Oxidative stress and mitochondrial dysfunction in germ cells are suggested to contribute to phthalate-induced disruption of spermatogenesis in rodents, and Leydig cells are one of the main targets of phthalates' testicular toxicity. Selenium is known to be involved in the modulation of intracellular redox equilibrium, and plays a critical role in testis, sperm, and reproduction. This study was aimed to investigate the oxidative stress potential of DEHP and its consequences in testicular cells, and examine the possible protective effects of selenium using the MA-10 mouse Leydig tumor cell line as a model. In the presence and absence of selenium compounds [30 nM sodium selenite (SS), and 10 {mu}M selenomethionine (SM)], the effects of exposure to DEHP and its main metabolite mono(2-ethylhexyl)-phthalate (MEHP) on the cell viability, enzymatic and non-enzymatic antioxidant status, ROS production, p53 expression, and DNA damage by alkaline Comet assay were investigated. The overall results of this study demonstrated the cytotoxicity and genotoxicity potential of DEHP, where MEHP was found to be more potent than the parent compound. SS and SM produced almost the same level of protection against antioxidant status modifying effects, ROS and p53 inducing potentials, and DNA damaging effects of the two phthalate derivatives. It was thus shown that DEHP produced oxidative stress in MA-10 cells, and selenium supplementation appeared to be an effective redox regulator in the experimental conditions used in this study, emphasizing the critical importance of the appropriate selenium status.

  14. Mutation Analysis of the LH Receptor Gene in Leydig Cell Adenoma and Hyperplasia and Functional and Biochemical Studies of Activating Mutations of the LH Receptor Gene

    PubMed Central

    Lumbroso, Serge; Verhoef-Post, Miriam; Richter-Unruh, Annette; Looijenga, Leendert H. J.; Funaro, Ada; Beishuizen, Auke; van Marle, André; Drop, Stenvert L. S.; Themmen, Axel P. N.

    2011-01-01

    Context: Germline and somatic activating mutations in the LH receptor (LHR) gene have been reported. Objective: Our objective was to perform mutation analysis of the LHR gene of patients with Leydig cell adenoma or hyperplasia. Functional studies were conducted to compare the D578H-LHR mutant with the wild-type (WT)-LHR and the D578G-LHR mutant, a classic cause of testotoxicosis. The three main signal transduction pathways in which LHR is involved were studied. Patients: We describe eight male patients with gonadotropin-independent precocious puberty due to Leydig cell adenoma or hyperplasia. Results: The D578H-LHR mutation was found in the adenoma or nodule with hyperplasia in all but two patients. D578H-LHR displayed a constitutively increased but noninducible production of cAMP, led to a very high production of inositol phosphates, and induced a slight phosphorylation of p44/42 MAPK in the absence of human chorionic gonadotropin. The D578G-LHR showed a response intermediate between WT-LHR and the D578H-LHR. Subcellular localization studies showed that the WT-LHR was almost exclusively located at the cell membrane, whereas the D578H-LHR showed signs of internalization. D578H-LHR was the only receptor to colocalize with early endosomes in the absence of human chorionic gonadotropin. Conclusions: Although several LHR mutations have been reported in testotoxicosis, the D578H-LHR mutation, which has been found only as a somatic mutation, appears up until now to be specifically responsible for Leydig cell adenomas. This is reflected by the different activation of the signal transduction pathways, when compared with the WT-LHR or D578G-LHR, which may explain the tumorigenesis in the D578H mutant. PMID:21490077

  15. Localized irradiation of testes with carcinoma in situ: Effects on Leydig cell function and eradication of malignant germ cells in 20 patients

    SciTech Connect

    Giwercman, A.; von der Maase, H.; Berthelsen, J.G.; Rorth, M.; Bertelsen, A.; Skakkebaek, N.E. )

    1991-09-01

    Twenty men (median age, 31 yr) previously treated for unilateral testicular cancer received localized irradiation in a dose of 20 Gray in 10 fractions for carcinoma in situ of the remaining testis. Follow-up testicular biopsies performed 3 (n = 19) and 24 (n = 14) months after the treatment showed in all cases a Sertoli cell-only pattern. Hormonal evaluation was performed before as well as 3, 12, 24, and 36 months after radiation treatment. Endocrine parameters were followed for a median of 30 months (3-36 months). Baseline serum testosterone values decreased during the follow-up period from 13.3 {plus minus} 6.0 to 10.8 {plus minus} 6.4 nmol/L (mean {plus minus} SD), although the decrease was not statistically significant (P = 0.06). Serum LH values increased during the first 3 months of follow-up from 10.4 {plus minus} 5.4 to 15.6 {plus minus} 7.3 IU/L (P less than 0.0001) and then remained unchanged. Significant decreases in GnRH- and hCG-stimulated testosterone levels also indicated an impairment of Leydig cell function. FSH levels increased (P less than 0.0001) during the first 3 months of follow-up from 21.8 {plus minus} 11.1 to 33.2 {plus minus} 13.2 IU/L. The authors conclude that localized irradiation of 20 Gray eradicated carcinoma in situ germ cells. Development of a second testicular cancer has until now been prevented. Leydig cell function was partially impaired by the radiation dose given.

  16. Hydrodynamic properties of the gonadotropin receptor from a murine Leydig tumor cell line are altered by desensitization

    SciTech Connect

    Rebois, R.V.; Bradley, R.M.; Titlow, C.C.

    1987-10-06

    The murine Leydig tumor cell line 1 (MLTC-1) contains gonadotropin receptors (GR) that are coupled to adenylate cyclase through the stimulatory guanine nucleotide binding protein (G/sub s/). The binding of human choriogonadotropin (hGC) causes MLTC-1 cells to accumulate cAMP. With time, the ability of MLTC-1 cells to respond to hCG is attenuated by a process called desensitization. The hydrodynamic properties of GR from control and desensitized MLTC-1 cells were studied. Sucrose density gradient sedimentation in H/sub 2/O and D/sub 2/O and gel filtration chromatography were used to estimate the Stokes radius (a), partial specific volume (v/sub c/), sedimentation coefficient (s/sub 20,w/), and molecular weight (M/sub r/) of the detergent-solubilized hormone-receptor complex (hCG-GR). (/sup 125/I)hCG was bound to MLTC-1 cells under conditions that allow (37/sup 0/C) or prevent (0/sup 0/C) desensitization, and hCG-GR was solubilized in Triton X-100. In the absence of desensitization, control hCG-GR had a M/sub r/ of 213,000, whereas desensitized hCG-GR had a M/sub r/ of 158,000. Deglycosylated hCG (DG-HCG) is an antagonist that binds to GR with high affinity but fails to stimulate adenylate cyclase or cause desensitization. (/sup 125/I)DG-hCG was bound to MLTC-1 cells and DG-hCG-GR solubilized in Triton X-100. The hydrodynamic properties of DG-hCG-GR were the same as that for control hCG-GR. There was no evidence for the association of adenylate cyclase or G/sub s/ with GR in Triton X-100 solubilized preparations. When hCG was cross-linked to GR and solubilized with sodium dodecyl sulfate (SDS), the M/sub r/ was found to be 116,000, which was similar to that determined by SDS-polyacrylamide gel electrophoresis and less than that of the Triton X-100 solubilized control hCG-GR.

  17. Interaction of putative estrogens and the estrogen receptor system in Leydig cells in the BALB/c mouse testis resulting in the initiation of DNA synthesis

    SciTech Connect

    Juriansz, R.L.

    1986-01-01

    Continuous administration of estrogens for 7-9 months, both steroidal and nonsteroidal, to male BALB/c mice, leads to the formation of testicular Leydig cell tumors. Three days following the subcutaneous implantation of a pellet of estrogen in cholesterol, there is a peak in the incorporation of /sup 3/H-thymidine into the DNA of the interstitial cells. These effects are hypothesized to be mediated by the estrogen receptor system in the Leydig cell. Common experimental techniques for the measurement of hormone binding, such as dextran coated charcoal treatment, proved to be impossible to employ in this system, therefore a procedure was developed using hydroxyapatite to obtain binding data. The cytosolic estrogen receptor was found to have a dissociation constant for estradiol-17..beta.. of 6.5 x 10/sup -8/ M, while that of the nuclear estrogen receptor was 1.25 x 10/sup -8/ M. Competition assays were utilized to determine the cytosolic estrogen receptor's affinity for nonsteroidal estrogens, steroidal estrogens, and triphenylethylene.

  18. A Rare Case of Intra-Endometrial Leiomyoma of Uterus Simulating Degenerated Submucosal Leiomyoma Accompanied by a Large Sertoli-Leydig Cell Tumor.

    PubMed

    Jeong, Kyungah; Lee, Sa Ra; Park, Sanghui

    2016-03-01

    A 50-year-old peri-menopausal woman presented with hard palpable mass on her lower abdomen and anemia from heavy menstrual bleeding. Ultrasonography showed a 13×12 cm sized hypoechoic solid mass in pelvis and a 2.5×2 cm hypoechoic cystic mass in uterine endometrium. Abdomino-pelvic computed tomography revealed a hypodense pelvic mass without enhancement, suggesting a leiomyoma of intraligamentary type or sex cord tumor of right ovary with submucosal myoma of uterus. Laparoscopy revealed a large Sertoli-Leydig cell tumor of right ovary with a very rare entity of intra-endometrial uterine leiomyoma accompanied by adenomyosis. The final diagnosis of ovarian sex-cord tumor (Sertoli-Leydig cell), stage Ia with intra-endometrial leiomyoma with adenomyosis, was made. Considering the large size of the tumor and poorly differentiated nature, 6 cycles of chemotherapy with Taxol and Carboplatin regimen were administered. There is neither evidence of major complications nor recurrence during 20 months' follow-up. PMID:26847310

  19. A Rare Case of Intra-Endometrial Leiomyoma of Uterus Simulating Degenerated Submucosal Leiomyoma Accompanied by a Large Sertoli-Leydig Cell Tumor

    PubMed Central

    Jeong, Kyungah; Park, Sanghui

    2016-01-01

    A 50-year-old peri-menopausal woman presented with hard palpable mass on her lower abdomen and anemia from heavy menstrual bleeding. Ultrasonography showed a 13×12 cm sized hypoechoic solid mass in pelvis and a 2.5×2 cm hypoechoic cystic mass in uterine endometrium. Abdomino-pelvic computed tomography revealed a hypodense pelvic mass without enhancement, suggesting a leiomyoma of intraligamentary type or sex cord tumor of right ovary with submucosal myoma of uterus. Laparoscopy revealed a large Sertoli-Leydig cell tumor of right ovary with a very rare entity of intra-endometrial uterine leiomyoma accompanied by adenomyosis. The final diagnosis of ovarian sex-cord tumor (Sertoli-Leydig cell), stage Ia with intra-endometrial leiomyoma with adenomyosis, was made. Considering the large size of the tumor and poorly differentiated nature, 6 cycles of chemotherapy with Taxol and Carboplatin regimen were administered. There is neither evidence of major complications nor recurrence during 20 months' follow-up. PMID:26847310

  20. Stimulation of cholesterol side-chain cleavage by a luteinizing-hormone-releasing hormone (luliberin) agonist (ICI 118630) in rat Leydig cells.

    PubMed Central

    Sullivan, M H; Cooke, B A

    1983-01-01

    The action of a luliberin (luteinizing-hormone-releasing hormone) agonist (ICI 118630) and lutropin (luteinizing hormone) on the activity of the cytochrome P-450 cholesterol side-chain cleavage enzyme in rat Leydig cells has been investigated. This has been carried out by studying the metabolism of exogenous (22R)-22- and 25-hydroxycholesterol to testosterone. It was found that both hydroxycholesterols increased testosterone production to higher levels than achieved by lutropin alone. Addition of luliberin agonist but not lutropin was found to increase further the metabolism of the hydroxycholesterol to testosterone; this occurred in the presence of saturating and subsaturating levels of the hydroxycholesterols. This effect of luliberin agonist was potentiated in the presence of lutropin. The protein synthesis inhibitor, cycloheximide, inhibited the luliberin agonist-induced stimulation of the hydroxycholesterol metabolism. At low calcium levels (1.1 microM), testosterone production was increased by addition of (22R)-22-hydroxycholesterol but the luliberin agonist effect was negated. The calmodulin inhibitor trifluoperazine inhibited (22R)-22-hydroxycholesterol-stimulated steroidogenesis and negated the luliberin agonist effect. These results indicate that luliberin agonist specifically increases the synthesis of the cytochrome P-450 cholesterol side-chain cleavage enzyme in rat testis Leydig cells. PMID:6230077

  1. Woman with virilizing congenital adrenal hyperplasia and Leydig cell tumor of the ovary.

    PubMed

    Fernández-García Salazar, Rosario; Muñoz-Darias, Carmen; Haro-Mora, Juan Jesús; Almaraz, M Cruz; Audí, Laura; Martínez-Tudela, Juana; Yahyaoui, Raquel; Esteva, Isabel

    2014-08-01

    We report the case of a 36-year-old woman with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, and corticosteroid replacement therapy since birth. She manifested persistent virilization and high testosterone levels that were attributed to nonadherence to medical treatment. The patient was referred to our gender unit for genitoplastic surgery. We recommended the patient for left oophorectomy after detecting an ovarian mass. Pathologic findings confirmed an ovarian hilus cell tumor. Testosterone levels fell back to normal and masculinization disappeared but ACTH remained elevated. This case represents a very rare type of primary ovarian tumor that must be considered in persistent virilizing symptoms in women with CAH. PMID:24702195

  2. A Yeast-Based Chemical Screen Identifies a PDE Inhibitor That Elevates Steroidogenesis in Mouse Leydig Cells via PDE8 and PDE4 Inhibition

    PubMed Central

    Demirbas, Didem; Wyman, Arlene R.; Shimizu-Albergine, Masami; Cakici, Ozgur; Beavo, Joseph A.; Hoffman, Charles S.

    2013-01-01

    A cell-based high-throughput screen (HTS) was developed to detect phosphodiesterase 8 (PDE8) and PDE4/8 combination inhibitors. By replacing the Schizosaccharomyces pombe PDE gene with the murine PDE8A1 gene in strains lacking adenylyl cyclase, we generated strains whose protein kinase A (PKA)-stimulated growth in 5-fluoro orotic acid (5FOA) medium reflects PDE8 activity. From our previously-identified PDE4 and PDE7 inhibitors, we identified a PDE4/8 inhibitor that allowed us to optimize screening conditions. Of 222,711 compounds screened, ∼0.2% displayed composite Z scores of >20. Additional yeast-based assays using the most effective 367 compounds identified 30 candidates for further characterization. Among these, compound BC8-15 displayed the lowest IC50 value for both PDE4 and PDE8 inhibition in in vitro enzyme assays. This compound also displays significant activity against PDE10A and PDE11A. BC8-15 elevates steroidogenesis in mouse Leydig cells as a single pharmacological agent. Assays using BC8-15 and two structural derivatives support a model in which PDE8 is a primary regulator of testosterone production by Leydig cells, with an additional role for PDE4 in this process. BC8-15, BC8-15A, and BC8-15C, which are commercially available compounds, display distinct patterns of activity against PDE4, PDE8, PDE10A, and PDE11A, representing a chemical toolkit that could be used to examine the biological roles of these enzymes in cell culture systems. PMID:23967182

  3. Leydig cell tumor

    MedlinePlus

    ... health care provider if you have symptoms of testicular cancer. Prevention Performing testicular self-examination (TSE) each month may help detect testicular cancer at an early stage, before it spreads. Finding ...

  4. Perfluorooctane Sulfonate Concentrations in Amniotic Fluid, Biomarkers of Fetal Leydig Cell Function, and Cryptorchidism and Hypospadias in Danish Boys (1980–1996)

    PubMed Central

    Toft, Gunnar; Jönsson, Bo A.G.; Bonde, Jens Peter; Nørgaard-Pedersen, Bent; Hougaard, David M.; Cohen, Arieh; Lindh, Christian H.; Ivell, Richard; Anand-Ivell, Ravinder; Lindhard, Morten S.

    2015-01-01

    Background Exposure to perfluorooctane sulfonate (PFOS) may potentially disturb fetal Leydig cell hormone production and male genital development. Objectives We aimed to study the associations between levels of amniotic fluid PFOS, fetal steroid hormone, and insulin-like factor 3 (INSL3) and the prevalence of cryptorchidism and hypospadias. Methods Using the Danish National Patient Registry, we selected 270 cryptorchidism cases, 75 hypospadias cases, and 300 controls with stored maternal amniotic fluid samples available in a Danish pregnancy-screening biobank (1980–1996). We used mass spectrometry to measure PFOS in amniotic fluid from 645 persons and steroid hormones in samples from 545 persons. INSL3 was measured by immunoassay from 475 persons. Associations between PFOS concentration in amniotic fluid, hormone levels, and genital malformations were assessed by confounder-adjusted linear and logistic regression. Results The highest tertile of PFOS exposure (> 1.4 ng/mL) in amniotic fluid was associated with a 40% (95% CI: –69, –11%) lower INSL3 level and an 18% (95% CI: 7, 29%) higher testosterone level compared with the lowest tertile (< 0.8 ng/mL). Amniotic fluid PFOS concentration was not associated with cryptorchidism or hypospadias. Conclusions Environmental PFOS exposure was associated with steroid hormone and INSL3 concentrations in amniotic fluid, but was not associated with cryptorchidism or hypospadias in our study population. Additional studies are needed to determine whether associations with fetal hormone levels may have long-term implications for reproductive health. Citation Toft G, Jönsson BA, Bonde JP, Nørgaard-Pedersen B, Hougaard DM, Cohen A, Lindh CH, Ivell R, Anand-Ivell R, Lindhard MS. 2016. Perfluorooctane sulfonate concentrations in amniotic fluid, biomarkers of fetal Leydig cell function, and cryptorchidism and hypospadias in Danish boys (1980–1996). Environ Health Perspect 124:151–156; http://dx.doi.org/10.1289/ehp.1409288

  5. Low reversibility of intracellular cAMP accumulation in mouse Leydig tumor cells (MLTC-1) stimulated by human Luteinizing Hormone (hLH) and Chorionic Gonadotropin (hCG).

    PubMed

    Klett, Danièle; Meslin, Philippine; Relav, Lauriane; Nguyen, Thi Mong Diep; Mariot, Julie; Jégot, Gwenhaël; Cahoreau, Claire; Combarnous, Yves

    2016-10-15

    In order to study the intracellular cAMP response kinetics of Leydig cells to hormones with LH activity, we used MLTC-1 cells transiently expressing a chimeric cAMP-responsive luciferase so that real-time variations of intracellular cAMP concentration could be followed using oxiluciferin luminescence produced from catalyzed luciferin oxidation. The potencies of the different LHs and CGs were evaluated using areas under the curves (AUC) of their kinetics over 60 min stimulation. All mammalian LHs and CGs tested were found to stimulate cAMP accumulation in these cells. The reversibility of this stimulation was studied by removing the hormone from the culture medium after 10 min of incubation. The ratios of kinetics AUC after removing or not the hormone were used to evaluate the stimulation reversibility of each hormone. Natural and recombinant hLHs and hCGs were found to exhibit slowly reversible activation compared to pituitary rat, ovine, porcine, camel and equine LHs, serum-derived eCG (PMSG) and recombinant eLH/CGs. Carbohydrate side chains are not involved in this phenomenon since natural and recombinant homologous hormones exhibit the same reversibility rates. It is still unknown whether only one human subunit, α or β, is responsible for this behaviour or whether it is due to a particular feature of the hLH and hCG quaternary structure. PMID:27373440

  6. Male rats exposed in utero to di(n-butyl) phthalate: Age-related changes in Leydig cell smooth endoplasmic reticulum and testicular testosterone-biosynthesis enzymes/proteins.

    PubMed

    Motohashi, Masaya; Wempe, Michael F; Mutou, Tomoko; Takahashi, Hiroyuki; Kansaku, Norio; Ikegami, Masahiro; Inomata, Tomo; Asari, Masao; Wakui, Shin

    2016-01-01

    This study investigated the age-related (i.e., weeks 5, 7, 9, 14 and 17) morphological changes of Leydig cell smooth endoplasmic reticulum (LCs-ER) and testicular testosterone biosynthesis/protein expression in rats in utero exposed to di(n-butyl) phthalate (DBP) (intragastrically; 100mg/kg/day) on days 12-21 post-conception. Ultrastructural observations revealed the LCs-ER of the DBP group were non-dilated until peri-puberty, and thereafter decreased and disappeared. RT-PCR and Western blotting analyses revealed that StAR and P450scc levels in the DBP group were significantly lower at 5 and 7 weeks compared with the vehicle group but became similar during weeks 9-17. Although 3β-HSD, P450c17, and 17β-HSD levels of mRNA and protein in the DBP group were similar to the vehicle control group at 5 and 7 weeks of age, they were significantly lower during weeks 9-17. In utero DBP exposure results in age-related LCs-ER changes corresponding to reduction of testicular testosterone biosynthesis enzymes/associated proteins. PMID:26706031

  7. Effect of cAMP on the cholesterol side-chain cleavage enzyme complex (CSCC) in MA-10 Leydig tumor cell mitochondria

    SciTech Connect

    Chaudhary, L.R.; Stocco, D.M.

    1986-05-01

    The rate limiting step in steroid biosynthesis is catalyzed by the cholesterol side-chain cleavage complex (CSCC) which is located on the matrix side of the inner mitochondrial membrane. It has been shown that addition of cAMP or LH/hCG to MA-10 mouse Leydig tumor cells in culture increases the production of progesterone as the major steroid. To examine the effect of cAMP on CSCC activity, cells were grown in culture flasks in the presence or absence of 10/sup -3/M cAMP for 3 h. Cells were harvested and mitochondria were isolated. Reaction conditions were optimized and contained 465000 DPM (26-/sup 14/C)cholesterol, 10mM NaCN, 0.5mM NADPH, 5mM CaCl/sub 2/, 60mM KCl and mitochondria. Reactions were stopped by the addition of ethanol and water and liberated (26-/sup 14/C)isocaproic acid was separated from uncleaved cholesterol by extraction with hexane and chloroform resulting in the retention of isocaproic acid in the aqueous layer. These experiments demonstrated a significant increase in (/sup 14/C)isocaproic acid production by mitochondria isolated from the cells grown in the presence of cAMP when compared to controls indicating that cAMP enhances the production of progesterone by increasing the activity of CSCC. Whether cAMP brings about this increase primarily through phosphorylation/dephosphorylation reactions or through some other mechanism is not clear at this time.

  8. Protein Modifications Regulate the Role of 14-3-3γ Adaptor Protein in cAMP-induced Steroidogenesis in MA-10 Leydig Cells*

    PubMed Central

    Aghazadeh, Yasaman; Ye, Xiaoying; Blonder, Josip; Papadopoulos, Vassilios

    2014-01-01

    The 14-3-3 protein family comprises adaptors and scaffolds that regulate intracellular signaling pathways. The 14-3-3γ isoform is a negative regulator of steroidogenesis that is hormonally induced and transiently functions at the initiation of steroidogenesis by delaying maximal steroidogenesis in MA-10 mouse tumor Leydig cells. Treatment of MA-10 cells with the cAMP analog 8-bromo-cAMP (8-Br-cAMP), which stimulates steroidogenesis, triggers the interaction of 14-3-3γ with the steroidogenic acute regulatory protein (STAR) in the cytosol, limiting STAR activity to basal levels. Over time, this interaction ceases, allowing for a 2-fold induction in STAR activity and maximal increase in the rate of steroid formation. The 14-3-3γ/STAR pattern of interaction was found to be opposite that of the 14-3-3γ homodimerization pattern. Phosphorylation and acetylation of 14-3-3γ showed similar patterns to homodimerization and STAR binding, respectively. 14-3-3γ Ser58 phosphorylation and 14-3-3γ Lys49 acetylation were blocked using trans-activator of HIV transcription factor 1 peptides coupled to 14-3-3γ sequences containing Ser58 or Lys49. Blocking either one of these modifications further induced 8-Br-cAMP-induced steroidogenesis while reducing lipid storage, suggesting that the stored cholesterol is used for steroid formation. Taken together, these results indicate that Ser58 phosphorylation and Lys49 acetylation of 14-3-3γ occur in a coordinated time-dependent manner to regulate 14-3-3γ homodimerization. 14-3-3γ Ser58 phosphorylation is required for STAR interactions under control conditions, and 14-3-3γ Lys49 acetylation is important for the cAMP-dependent induction of these interactions. PMID:25086053

  9. 7,12-dimethylbenz[a]anthracene induces sertoli-leydig-cell tumors in the follicle-depleted ovaries of mice treated with 4-vinylcyclohexene diepoxide.

    PubMed

    Craig, Zelieann R; Davis, John R; Marion, Samuel L; Barton, Jennifer K; Hoyer, Patricia B

    2010-02-01

    Ovarian cancer is associated with high mortality due to its late onset of symptoms and lack of reliable screening methods for early detection. Furthermore, the incidence of ovarian cancer is higher in postmenopausal women. Mice rendered follicle-depleted through treatment with 4-vinylcyclohexene diepoxide (VCD) are a model of ovary-intact menopause. The present study was designed to induce ovarian neoplasia in this model by treating mice with 7,12-dimethylbenz[a]anthracene (DMBA). Female B6C3F1 mice (age, 28 d) received intraperitoneal sesame oil (vehicle; VCD- groups) as a control or VCD (160 mg/kg; VCD+ groups) daily for 20 d to cause ovarian failure. Four months after the onset of dosing, mice from each group received a single injection of DMBA (VCD-DMBA+ and VCD+DMBA+ groups, n = 15 per group) or vehicle control (VCD-DMBA-, n = 15; VCD+ DMBA-, n = 14) under the bursa of the right ovary. Ovaries were collected 3 or 5 mo after injection and processed for histologic evaluation. Immunohistochemistry was used to confirm classification of neoplasms. None of the animals in the VCD-DMBA- and VCD-DMBA+ groups (that is, mice still undergoing estrus) had tumors at either time point. At the 3-mo time point, 12.5% of the VCD+DMBA+ mice had ovarian tumors; at 5 mo, 57.1% of the VCD+DMBA+ and 14.3% of VCD+DMBA- ovaries had neoplasms. Neoplasms stained positively for inhibin alpha (granulosa cells) and negatively for keratin 7 (surface epithelium), thus confirming classification of the lesions as Sertoli-Leydig cell tumors. These findings provide evidence for an increased incidence of DMBA-induced ovarian neoplasms in the ovaries of follicle-depleted mice compared with that in age-matched cycling controls. PMID:20158943

  10. Elevated expression of the Sertoli cell androgen receptor disrupts male fertility.

    PubMed

    Hazra, Rasmani; Upton, Dannielle; Desai, Reena; Noori, Omar; Jimenez, Mark; Handelsman, David J; Allan, Charles M

    2016-08-01

    Recently, we created a unique gain-of-function mouse model with Sertoli cell-specific transgenic androgen receptor expression (TgSCAR) showing that SCAR activity controls the synchronized postnatal development of somatic Sertoli and Leydig cells and meiotic-postmeiotic germ cells. Moderate TgSCAR (TgSCAR(m)) expression reduced testis size but had no effect on male fertility. Here, we reveal that higher TgSCAR expression (TgSCAR(H)) causes male infertility. Higher SCAR activity, shown by upregulated AR-dependent transcripts (Rhox5, Spinw1), resulted in smaller adult TgSCAR(H) testes (50% of normal) despite normal or elevated circulating and intratesticular testosterone levels. Unlike fertile TgSCAR(m) males, testes of adult TgSCAR(H) males exhibited focal regions of interstitial hypertrophy featuring immature adult Leydig cells and higher intratesticular dihydrotestosterone and 5α-androstane 3α,17β-diol levels that are normally associated with pubertal development. Mature TgSCAR(H) testes also exhibited markedly reduced Sertoli cell numbers (70%), although meiotic and postmeiotic germ cell/Sertoli cell ratios were twofold higher than normal, suggesting that elevated TgSCAR activity supports excessive spermatogenic development. Concurrent with the higher germ cell load of TgSCAR(H) Sertoli cells were increased levels of apoptotic germ cells in TgSCAR(H) relative to TgSCAR(m) testes. In addition, TgSCAR(H) testes displayed unique morphological degeneration that featured accumulated cellular and spermatozoa clusters in dilated channels of rete testes, consistent with reduced epididymal sperm numbers. Our findings reveal for the first time that excessive Sertoli cell AR activity in mature testes can reach a level that disturbs Sertoli/germ cell homeostasis, impacts focal Leydig cell function, reduces sperm output, and disrupts male fertility. PMID:27354237

  11. Noncoordinate regulation of de novo synthesis of cytochrome P-450 cholesterol side-chain cleavage and cytochrome P-450 17 alpha-hydroxylase/C17-20 lyase in mouse Leydig cell cultures: relation to steroid production

    SciTech Connect

    Anakwe, O.O.; Payne, A.H. )

    1987-09-01

    The role of cAMP in the regulation of the amount and synthesis of cytochrome P-450 cholesterol side-chain cleavage (P-450scc) and cytochrome P-450 17 alpha-hydroxylase/C17-20 lyase P-450(17 alpha) was investigated in mouse Leydig cell cultures. In the absence of cAMP, the amount of immunoreactive P-450(17 alpha) decreased to less than 5% by day 4 and was undetectable between days 7 and 11. In contrast, the amount of immunoreactive P-450scc remained relatively constant throughout the same period. Treatment of Leydig cell cultures for 4 days with 0.05 mM 8-bromo-cAMP initiated on day 7 increased the amount of P-450(17 alpha) with relatively little effect on the amount of P-450scc. The rate of de novo synthesis of each of the P-450 enzymes was studied by determining (35S)methionine incorporation into newly synthesized protein. In the absence of cAMP, de novo synthesis of P-450(17 alpha) ceased while the rate of de novo synthesis of P-450scc increased with time in culture between days 2 and 11. Treatment with cAMP initiated on day 7 of culture caused a time-dependent increase in the rate of de novo synthesis of P-450(17 alpha) on days 9 and 11 equivalent to 40% and 60%, respectively, of that observed in freshly isolated Leydig cells. The rate of de novo synthesis of P-450scc was increased 2-fold relative to untreated cultures on days 9 and 11. De novo synthesis of P-450(17 alpha) ceased when cAMP was removed on day 11 and restored when cAMP was added again on day 13 of culture.

  12. Steroid-mediated inhibition of cAMP induced de novo synthesis of cytochrome P-450/sub 17 / in Leydig cell cultures

    SciTech Connect

    Hales, D.B.; Sha, L.; Payne, A.H.

    1987-05-01

    The present study was designed to investigate the mechanism by which testosterone (T), produced during cAMP induction of P-450/sub 17 /, modulates the rate of its de novo synthesis. Purified Leydig cells (LC) were maintained in culture for 7 days prior to the initiation of treatment. De novo synthesis was determined by TVS-methionine incorporation, immunoprecipitation with specific antibody, separation by SDS-gel electrophoresis and quantitation by laser densitometry. Treatment of LC with 0.05 mM 8-Br-cAMP (cA) results in a time-dependent increase in the rate of de novo synthesis of P-450/sub 17 / which is increased 2 fold when T production is inhibited by aminoglutethimide (AG). The addition of increasing concentrations of the androgen receptor antagonist, hydroxyflutamide (1-10 M), to cA treated LC enhances the rate of synthesis similar to that seen in cA-treated LC in which T production was inhibited by AG. The addition of increasing concentrations of T (0.05-5 M) or the androgen agonist, mibolerone (1-5 M), to cA + AG treated LC causes a dose-dependent reversal of the AG-enhanced increase in the rate of cA-induced de novo synthesis of P-450/sub 17 /. Addition of estradiol (1 M) or dexamethasone (1 M) was without effect. These data indicate that T produced during cA induction of P-450/sub 17 / negatively regulates the rate of synthesis of this cytochrome P-450 enzyme by an androgen receptor mediated mechanism.

  13. Effects of Prenatal Leydig Cell Function on the Ratio of the Second to Fourth Digit Lengths in School-Aged Children

    PubMed Central

    Mitsui, Takahiko; Araki, Atsuko; Imai, Ayako; Sato, Sakiko; Miyashita, Chihiro; Ito, Sachiko; Sasaki, Seiko; Kitta, Takeya; Moriya, Kimihiko; Cho, Kazutoshi; Morioka, Keita; Kishi, Reiko; Nonomura, Katsuya

    2015-01-01

    Prenatal sex hormones can induce abnormalities in the reproductive system and adversely impact on genital development. We investigated whether sex hormones in cord blood influenced the ratio of the second to fourth digit lengths (2D/4D) in school-aged children. Of the 514 children who participated in a prospective cohort study on birth in Sapporo between 2002 and 2005, the following sex hormone levels were measured in 294 stored cord blood samples (135 boys and 159 girls); testosterone (T), estradiol (E), progesterone, LH, FSH, inhibin B, and insulin-like factor 3 (INSL3). A total of 350 children, who were of school age and could be contacted for this survey, were then requested via mail to send black-and-white photocopies of the palms of both the left and right hands. 2D/4D was calculated in 190 children (88 boys and 102 girls) using photocopies and derived from participants with the characteristics of older mothers, a higher annual household income, higher educational level, and fewer smokers among family members. 2D/4D was significantly lower in males than in females (p<0.01). In the 294 stored cord blood samples, T, T/E, LH, FSH, Inhibin B, and INSL3 levels were significantly higher in samples collected from males than those from females. A multivariate regression model revealed that 2D/4D negatively correlated with INSL3 in males and was significantly higher in males with <0.32 ng/mL of INSL3 (p<0.01). No correlations were observed between other hormones and 2D/4D. In conclusion, 2D/4D in school-aged children, which was significantly lower in males than in females, was affected by prenatal Leydig cell function. PMID:25746668

  14. Expression Analysis of Gnrh1 and Gnrhr1 in Spermatogenic Cells of Rat

    PubMed Central

    Ciaramella, Vincenza; Pariante, Paolo; Fasano, Silvia; Pierantoni, Riccardo

    2015-01-01

    Hypothalamic Gonadotropin Releasing Hormone (GnRH), via GnRH receptor (GnRHR), is the main actor in the control of reproduction, in that it induces the biosynthesis and the release of pituitary gonadotropins, which in turn promote steroidogenesis and gametogenesis in both sexes. Extrabrain functions of GnRH have been extensively described in the past decades and, in males, local GnRH activity promotes the progression of spermatogenesis and sperm functions at several levels. The canonical localization of Gnrh1 and Gnrhr1 mRNA is Sertoli and Leydig cells, respectively, but ligand and receptor are also expressed in germ cells. Here, we analysed the expression rate of Gnrh1 and Gnrhr1 in rat testis (180 days old) by quantitative real-time PCR (qPCR) and by in situ hybridization we localized Gnrh1 and Gnrhr1 mRNA in different spermatogenic cells of adult animals. Our data confirm the testicular expression of Gnrh1 and of Gnrhr1 in somatic cells and provide evidence that their expression in the germinal compartment is restricted to haploid cells. In addition, not only Sertoli cells connected to spermatids in the last steps of maturation but also Leydig and peritubular myoid cells express Gnrh1. PMID:25861269

  15. Comments on Li et al. Effects of in Utero Exposure to Dicyclohexyl Phthalate on Rat Fetal Leydig Cells. Int. J. Environ. Res. Public Health 2016, 13, 246

    PubMed Central

    Svingen, Terje

    2016-01-01

    Profiling the expression levels of genes or proteins in tissues comprising two or more cell types is commonplace in biological sciences. Such analyses present particular challenges, however, for example a potential shift in cellular composition, or ‘cellularity’, between specimens. That is, does an observed change in expression level represent what occurs within individual cells, or does it represent a shift in the ratio of different cell types within the tissue? This commentary attempts to highlight the importance of considering cellularity when interpreting quantitative expression data, using the mammalian testis and a recent study on the effects of phthalate exposure on testis function as an example. PMID:27231928

  16. Comments on Li et al. Effects of in Utero Exposure to Dicyclohexyl Phthalate on Rat Fetal Leydig Cells. Int. J. Environ. Res. Public Health 2016, 13, 246.

    PubMed

    Svingen, Terje

    2016-01-01

    Profiling the expression levels of genes or proteins in tissues comprising two or more cell types is commonplace in biological sciences. Such analyses present particular challenges, however, for example a potential shift in cellular composition, or 'cellularity', between specimens. That is, does an observed change in expression level represent what occurs within individual cells, or does it represent a shift in the ratio of different cell types within the tissue? This commentary attempts to highlight the importance of considering cellularity when interpreting quantitative expression data, using the mammalian testis and a recent study on the effects of phthalate exposure on testis function as an example. PMID:27231928

  17. Association of luteinizing hormone receptor gene expression with cell cycle progression in granulosa cells

    PubMed Central

    Cannon, Jennifer D.; Seekallu, Srinivas V.; VandeVoort, Catherine A.; Chaffin, Charles L.

    2009-01-01

    During hormonally induced ovarian follicle growth, granulosa cell proliferation increases and returns to baseline prior to the administration of an ovulatory stimulus. Several key genes appear to follow a similar pattern, including the luteinizing hormone receptor (LHCGR), suggesting an association between cell cycle progression and gene expression. The expression of LHCGR mRNA in granulosa cells isolated from immature rats and treated in culture with FSH increased in a time-dependent manner, whereas administration of the cell cycle inhibitor mimosine completely suppressed expression. Although forskolin was able to induce luteinization in cells treated with mimosine, human chorionic gonadotropin had no effect, indicating the functional loss of LHCGR. The effects of mimosine on cell cycle progression and LHCGR mRNA expression were reversible within 24 h of mimosine removal. Cell cycle inhibition did not alter the stability of LHCGR mRNA, indicating that the primary effect was at the transcriptional level. To determine whether the relationship between LHCGR expression and cell cycle were relevant in vivo, immature rats were given a bolus of PMSG, followed by a second injection of either saline or PMSG 24 h later to augment levels of proliferation. The expression of LHCGR mRNA was elevated in the ovaries of animals receiving a supplement of PMSG. Mimosine also blocked cell cycle progression and LHCGR mRNA expression in macaque granulosa cells isolated following controlled ovarian stimulation cycles and in two different mouse Leydig tumor lines. These data collectively indicate that LHCGR mRNA is expressed as a function of the passage of cells across the G1-S phase boundary. PMID:19293332

  18. Regulation of Translocator Protein 18 kDa (TSPO) Expression in Rat and Human Male Germ Cells.

    PubMed

    Manku, Gurpreet; Culty, Martine

    2016-01-01

    Translocator protein 18 kDa (TSPO) is a high affinity cholesterol- and drug-binding protein highly expressed in steroidogenic cells, such as Leydig cells, where it plays a role in cholesterol mitochondrial transport. We have previously shown that TSPO is expressed in postnatal day 3 rat gonocytes, precursors of spermatogonial stem cells. Gonocytes undergo regulated phases of proliferation and migration, followed by retinoic acid (RA)-induced differentiation. Understanding these processes is important since their disruption may lead to the formation of carcinoma in situ, a precursor of testicular germ cell tumors (TGCTs). Previously, we showed that TSPO ligands do not regulate gonocyte proliferation. In the present study, we found that TSPO expression is downregulated in differentiating gonocytes. Similarly, in F9 embryonal carcinoma cells, a mouse TGCT cell line with embryonic stem cell properties, there is a significant decrease in TSPO expression during RA-induced differentiation. Silencing TSPO expression in gonocytes increased the stimulatory effect of RA on the expression of the differentiation marker Stra8, suggesting that TSPO exerts a repressive role on differentiation. Furthermore, in normal human testes, TSPO was located not only in Leydig cells, but also in discrete spermatogenic phases such as the forming acrosome of round spermatids. By contrast, seminomas, the most common type of TGCT, presented high levels of TSPO mRNA. TSPO protein was expressed in the cytoplasmic compartment of seminoma cells, identified by their nuclear expression of the transcription factors OCT4 and AP2G. Thus, TSPO appears to be tightly regulated during germ cell differentiation, and to be deregulated in seminomas, suggesting a role in germ cell development and pathology. PMID:27608010

  19. Immunohistochemical expression of SOX9 protein in immature, mature, and neoplastic canine Sertoli cells.

    PubMed

    Banco, Barbara; Palmieri, Chiara; Sironi, Giuseppe; Fantinato, Eleonora; Veronesi, Maria C; Groppetti, Debora; Giudice, Chiara; Martignoni, Benedetta; Grieco, Valeria

    2016-05-01

    Sex-determining region Y box9 gene (SOX9) protein plays a pivotal role in male sexual development. It regulates the transcription of the anti-Müllerian hormone gene promoting development of testis cords, multiplication, and maturation of Sertoli cells (SCs) and maintenance of spermatogenesis in adult testis. The immunohistochemical expression of SOX9 in normal testes has been reported in humans, mice, and rats. The present study aimed to investigate the expression of SOX9 in canine SCs during testicular maturation and neoplastic transformation. Canine testicular samples derived from three fetuses, four newborns, four prepubertal puppies, five adult dogs, 31 Sertoli cell tumors (SCTs) (one metastasizing), and five Leydig cell tumors (LCTs) were selected from departmental archive and tested immunohistochemically with a polyclonal antibody against SOX9 (1:150). All SCs from fetal, neonatal, and adult testes had a strong and exclusively nuclear labeling for SOX9. In SCs from prepubertal testes, SOX9 staining was highly variable with one negative sample (one of four), two samples with exclusively nuclear staining (two of four), and one with both nuclear and cytoplasmic labeling (one of four). Leydig cells (LCs) and LCTs were always negative. All 31 SCTs were positive for SOX9. The expression of SOX9 was nuclear, nuclear and cytoplasmic, and exclusively cytoplasmic in 18 of 31, 11 of 31, and two of 31 SCTs, respectively. This first report on the immunohistochemical expression of SOX9 in canine testes reports that in normal SCs from fetal, neonatal, and adult testes SOX9 labeled the nucleus, as in humans and laboratory animals. The cytoplasmic labeling observed in one prepubertal pairs of testes and in 11 SCTs could reflect SC immaturity or dedifferentiation, paralleling results observed in rat testes. The expression of SOX9 in SCs and SCTs and its absence in LCs and LCTs suggests that SOX9 is a reliable diagnostic marker for both normal and neoplastic SCs. PMID:26777558

  20. Fertility-sparing management and obstetric outcomes in a 20-year-old patient with a Sertoli-Leydig cell tumor of the ovary: A case report and review of the literature

    PubMed Central

    Stavrakis, Thomas; Kalogiannidis, Ioannis; Petousis, Stamatios; Tsompanidou, Chrisoula; Delkos, Dimitris; Prapas, Nikolaos; Rousso, David

    2016-01-01

    Sertoli-Leydig cell tumors (SLCTs) are an uncommon subtype of sex-cord stromal tumors of the ovary, which most commonly arise in women of reproductive age, creating an issue with regard to the preservation of fertility. The clinical manifestation of SLCTs varies widely, ranging from an asymptomatic clinical profile to extreme virilization. Correct diagnosis of SLCT is crucial and is primarily based on histopathological results. The current study presents the case of a 20-year-old woman who underwent unilateral salpingo-oophorectomy and adjuvant chemotherapy due to the diagnosis of an SLCT of the left ovary. Almost 2 years after the initial surgery, during the follow-up period, the patient conceived normally. Pregnancy was uneventful and the patient vaginally delivered a healthy infant at 38 weeks of gestation. A total of 1 year after delivery (3 years after the initial diagnosis), follow-up of the patient did not reveal any disease recurrence. In conclusion, SLCTs may be adequately treated by fertility-sparing surgery and chemotherapy in young women who wish to preserve their fertility. Natural conception, an uncomplicated pregnancy and a vaginal delivery are possible. PMID:27446397

  1. Seasonal expression of androgen receptor, aromatase, and estrogen receptor alpha and beta in the testis of the wild ground squirrel (Citellus dauricus Brandt).

    PubMed

    Li, Q; Zhang, F; Zhang, S; Sheng, X; Han, X; Weng, Q; Yuan, Z

    2015-01-01

    The aim of this study was to investigate the seasonal expression of androgen receptor (AR), estrogen receptors α and β (ERα and ERβ) and aromatase cytochrome P450 (P450arom) mRNA and protein by real-time PCR and immunohistochemistry in the wild ground squirrel (WGS) testes. Histologically, all types of spermatogenic cells including mature spermatozoa were identified in the breeding season (April), while spermatogonia and primary spermatocytes were observed in the nonbreeding season (June), and spermatogonia, primary spermatocytes and secondary spermatocytes were found in pre-hibernation (September). AR was present in Leydig cells, peritubular myoid cells and Sertoli cells in the breeding season and pre-hibernation with more intense staining in the breeding season, whereas AR was only found in Leydig cells in the nonbreeding season; P450arom was expressed in Leydig cells, Sertoli cells and germ cells during the breeding season, whereas P450arom was found in Leydig cells and Sertoli cells during pre-hibernation, but P450arom was not present in the nonbreeding season; stronger immunohistochemical signal for ERα was present in Sertoli cells and Leydig cells during the breeding season; ERβ was only expressed in Leydig cells of the breeding season. Consistent with the immunohistochemical results, the mean mRNA level of AR, P450arom, ERα and ERβ were higher in the testes of the breeding season when compared to pre-hibernation and the nonbreeding season. These results suggested that the seasonal changes in spermatogenesis and testicular recrudescence and regression process in WGSs might be correlated with expression levels of AR, P450arom and ERs, and that estrogen and androgen may play an important autocrine/paracrine role to regulate seasonal testicular function. PMID:25820559

  2. Sensitivity to cadmium-induced genotoxicity in rat testicular cells is associated with minimal expression of the metallothionein gene.

    PubMed

    Shiraishi, N; Hochadel, J F; Coogan, T P; Koropatnick, J; Waalkes, M P

    1995-02-01

    Cadmium is a carcinogenic metal. Although the mechanism of tumor induction is unknown, DNA/metal interactions may be involved. Metallothionein can protect against cadmium toxicity in our previous work it was shown to reduce cadmium genotoxicity in cultured cells. To extend these results, the genotoxicity of cadmium was studied in R2C cells, a rat testicular Leydig cell line. The R2C cells were very sensitive to cadmium-induced single-strand DNA damage (SSD), as measured by alkaline elution. SSD occurred in R2C cells after treatment with 25 and 50 microM CdCl2 for 2 hr. Prior work showed other cells required much higher levels of cadmium (approximately 500 microM) to induce genotoxicity. The genotoxic levels of cadmium (25-50 microM) were not cytotoxic in R2C cells as assessed by a metabolic activity (MTT) assay. Pretreatment of R2C cells with a low cadmium dose (2 microM, 24 hr) had no effect on cadmium-induced SSD, in contrast to prior work in other cells where such pretreatments reduced SSD through metallothionein gene activation. In fact, cadmium or zinc treatments resulted in little or no increase in metallothionein gene expression in R2C cells as determined by Northern blot analysis for metallothionein mRNA using cDNA or oligonucleotide probes and radioimmunoassay for metallothionein protein production. Basal metallothionein mRNA was essentially nondetectable. Induction of a cadmium-binding protein in R2C cells did occur, as determined by Cd-heme assay, but did not induce tolerance to SSD. In vivo, the Leydig cell is a target for cadmium carcinogenicity and its cadmium-binding protein is thought not to be a true metallothionein. These results indicate that R2C cells are sensitive to cadmium-induced genotoxicity and that this sensitivity is associated with minimal expression of the metallothionein gene. PMID:7871536

  3. Simvastatin and Dipentyl Phthalate Lower Ex vivo Testicular Testosterone Production and Exhibit Additive Effects on Testicular Testosterone and Gene Expression Via Distinct Mechanistic Pathways in the Fetal Rat

    EPA Science Inventory

    Sex differentiation of the male reproductive tract in mammals is driven, in part, by fetal androgen production. In utero, some phthalate esters (PEs) alter fetal Leydig cell differentiation, reducing the expression of several genes associated with steroid synthesis/transport, and...

  4. Heterogeneity of Ovarian Theca and Interstitial Gland Cells in Mice

    PubMed Central

    Miyabayashi, Kanako; Tokunaga, Kaori; Otake, Hiroyuki; Baba, Takashi; Shima, Yuichi; Morohashi, Ken-ichirou

    2015-01-01

    It has been established that two developmentally and functionally distinct cell types emerge within the mammalian testis and adrenal gland throughout life. Fetal and adult types of steroidogenic cells (i.e., testicular Leydig cells and adrenocortical cells) develop in the prenatal and postnatal period, respectively. Although the ovary synthesizes steroids postnatally, the presence of fetal-type steroidogenic cells has not been described. We had previously established transgenic mouse lines in which fetal Leydig cells were labeled with an EGFP reporter gene by the FLE (fetal Leydig enhancer) of the Ad4BP/SF-1 (Nr5a1) gene. In the present study, we examined the reporter gene expression in females and found that the reporter gene is turned on in postnatal ovaries. A comparison of the expressions of the EGFP and marker genes revealed that EGFP is expressed in not all but rather a proportion of steroidogenic theca and in interstitial gland cells in the ovary. This finding was further supported by experiments using BAC transgenic mice in which reporter gene expression recapitulated endogenous Ad4BP/SF-1 gene expression. In conclusion, our observations from this study strongly suggest that ovarian theca and interstitial gland cells in mice consist of at least two cell types. PMID:26039146

  5. Heterogeneity of ovarian theca and interstitial gland cells in mice.

    PubMed

    Miyabayashi, Kanako; Tokunaga, Kaori; Otake, Hiroyuki; Baba, Takashi; Shima, Yuichi; Morohashi, Ken-Ichirou

    2015-01-01

    It has been established that two developmentally and functionally distinct cell types emerge within the mammalian testis and adrenal gland throughout life. Fetal and adult types of steroidogenic cells (i.e., testicular Leydig cells and adrenocortical cells) develop in the prenatal and postnatal period, respectively. Although the ovary synthesizes steroids postnatally, the presence of fetal-type steroidogenic cells has not been described. We had previously established transgenic mouse lines in which fetal Leydig cells were labeled with an EGFP reporter gene by the FLE (fetal Leydig enhancer) of the Ad4BP/SF-1 (Nr5a1) gene. In the present study, we examined the reporter gene expression in females and found that the reporter gene is turned on in postnatal ovaries. A comparison of the expressions of the EGFP and marker genes revealed that EGFP is expressed in not all but rather a proportion of steroidogenic theca and in interstitial gland cells in the ovary. This finding was further supported by experiments using BAC transgenic mice in which reporter gene expression recapitulated endogenous Ad4BP/SF-1 gene expression. In conclusion, our observations from this study strongly suggest that ovarian theca and interstitial gland cells in mice consist of at least two cell types. PMID:26039146

  6. Strategies for multigene expression in eukaryotic cells.

    PubMed

    Mansouri, Maysam; Berger, Philipp

    2014-09-01

    Multigene delivery systems for heterologous multiprotein expression in mammalian cells are a key technology in contemporary biological research. Multiprotein expression is essential for a variety of applications, including multiparameter analysis of living cells in vitro, changing the fate of stem cells, or production of multiprotein complexes for structural biology. Depending on the application, these expression systems have to fulfill different requirements. For some applications, homogenous expression in all cells with defined stoichiometry is necessary, whereas other applications need long term expression or require that the proteins are not modified at the N- and C-terminus. Here we summarize available multiprotein expression systems and discuss their advantages and disadvantages. PMID:25034976

  7. Metachronous Bilateral Testicular Leydig-Like Tumors Leading to the Diagnosis of Congenital Adrenal Hyperplasia (Adrenogenital Syndrome)

    PubMed Central

    Vukina, Josip; Chism, David D.; Sharpless, Julie L.; Raynor, Mathew C.; Milowsky, Matthew I.; Funkhouser, William K.

    2015-01-01

    A 33-year-old male with a history of left testis Leydig cell tumor (LCT), 3-month status after left radical orchiectomy, presented with a rapidly enlarging (0.6 cm to 3.7 cm) right testicular mass. He underwent a right radical orchiectomy, sections interpreted as showing a similar Leydig cell-like oncocytic proliferation, with a differential diagnosis including metachronous bilateral LCT and metachronous bilateral testicular tumors associated with congenital adrenal hyperplasia (a.k.a. “testicular adrenal rest tumors” (TARTs) and “testicular tumors of the adrenogenital syndrome” (TTAGS)). Additional workup demonstrated a markedly elevated serum adrenocorticotropic hormone (ACTH) and elevated adrenal precursor steroid levels. He was diagnosed with congenital adrenal hyperplasia, 3β-hydroxysteroid dehydrogenase deficiency (3BHSD) type, and started on treatment. Metachronous bilateral testicular masses in adults should prompt consideration of adult presentation of CAH. Since all untreated CAH patients are expected to have elevated serum ACTH, formal exclusion of CAH prior to surgical resection of a testicular Leydig-like proliferation could be accomplished by screening for elevated serum ACTH. PMID:26351608

  8. Mammalian 43-kD acetylcholine receptor-associated protein (RAPsyn) is expressed in some nonmuscle cells

    SciTech Connect

    Musil, L.S.; Frail, D.E.; Merlie, J.P. )

    1989-05-01

    Torpedo electric organ and vertebrate neuromuscular junctions contain the receptor-associated protein of the synapse (RAPsyn) (previously referred to as the 43K protein), a nonactin, 43,000-Mr peripheral membrane protein associated with the cytoplasmic face of postsynaptic membranes at areas of high nicotinic acetylcholine receptor (AChR) density. Although not directly demonstrated, several lines of evidence suggest that RAPsyn is involved in the synthesis and/or maintenance of such AChR clusters. Microscopic and biochemical studies had previously indicated that RAPsyn expression is restricted to differentiated, AChR-synthesizing cells. Our recent finding that RAPsyn is also produced in undifferentiated myocytes led to to examine whether RAPsyn is synthesized in cell types that never express AChR (i.e., cells of other than skeletal muscle origin). Various primary and established rodent cell lines were metabolically labeled with (35S)methionine, and extracts were immunoprecipitated with a monospecific anti-RAPsyn serum. Analysis of these immunoprecipitates by SDS-PAGE revealed detectable RAPsyn synthesis in some (notably fibroblast and Leydig tumor cell lines and primary cardiac cells) but not all (hepatocyte- and lymphocyte-derived) cell types. These results were further substantiated by peptide mapping studies of RAPsyn immunoprecipitated from different cells and quantitation of RAPsyn-encoding mRNA levels in mouse tissues. RAPsyn synthesized in both muscle and nonmuscle cells was shown to be tightly associated with membranes. These findings demonstrate that RAPsyn is not specific to skeletal muscle-derived cells and imply that it may function in a capacity either in addition to or instead of AChR clustering.

  9. INHIBITION OF TESTICULAR STEROIDOGENESIS BY THE XENOESTROGEN BISPHENOL A IS ASSOCIATED WITH REDUCED PITUITARY LH SECRETION AND DECREASED STEROIDOGENIC ENZYME GENE EXPRESSION IN RAT LEYDIG CELLS

    EPA Science Inventory

    Exposure of humans to bisphenol A (BPA), a monomer in polycarbonate plastics and constituent of resins used in food packaging and denistry, is significant. In this report, exposure of rats to 2.4 ug/kg/day (a dose that approximates BPA levels in the environment) from postnatal da...

  10. Human neuroepithelial cells express NMDA receptors.

    PubMed

    Sharp, Christopher D; Fowler, M; Jackson, T H; Houghton, J; Warren, A; Nanda, A; Chandler, I; Cappell, B; Long, A; Minagar, A; Alexander, J S

    2003-11-13

    L-glutamate, an excitatory neurotransmitter, binds to both ionotropic and metabotropic glutamate receptors. In certain parts of the brain the BBB contains two normally impermeable barriers: 1) cerebral endothelial barrier and 2) cerebral epithelial barrier. Human cerebral endothelial cells express NMDA receptors; however, to date, human cerebral epithelial cells (neuroepithelial cells) have not been shown to express NMDA receptor message or protein. In this study, human hypothalamic sections were examined for NMDA receptors (NMDAR) expression via immunohistochemistry and murine neuroepithelial cell line (V1) were examined for NMDAR via RT-PCR and Western analysis. We found that human cerebral epithelium express protein and cultured mouse neuroepithelial cells express both mRNA and protein for the NMDA receptor. These findings may have important consequences for neuroepithelial responses during excitotoxicity and in disease. PMID:14614784

  11. Fas and Fas ligand expression in fetal and adult human testis with normal or deranged spermatogenesis.

    PubMed

    Francavilla, S; D'Abrizio, P; Rucci, N; Silvano, G; Properzi, G; Straface, E; Cordeschi, G; Necozione, S; Gnessi, L; Arizzi, M; Ulisse, S

    2000-08-01

    In mice, the Fas/Fas ligand (FasL) system has been shown to be involved in germ cell apoptosis. In the present study we evaluated the expression of Fas and Fas ligand (FasL) in fetal and adult human testis. Semiquantitative RT-PCR demonstrated the expression of Fas and FasL messenger ribonucleic acids in adult testis, but not in fetal testis (20-22 weeks gestation). In situ RT-PCR and immunohistochemistry experiments on adult human testis demonstrated the expression of FasL messenger ribonucleic acid and protein in Sertoli and Leydig cells, whereas the expression of Fas was confined to the Leydig cells and sporadic degenerating spermatocytes. The number of Fas-positive germ cells per 100 Sertoli cell nuclei was increased in 10 biopsies with postmeiotic germ cell arrest compared to 10 normal testis biopsies (mean, 3.82 +/- 0.45 vs. 2.02 +/- 0.29; P = 0.0001), but not in 10 biopsies with meiotic germ cell arrest (mean, 1.56 +/- 1.07). Fas and FasL proteins were not expressed in cases of idiopathic hypogonadotropic hypogonadism. Together, these findings may suggest that Fas/FasL expression in the human testis is developmentally regulated and under gonadotropin control. The increased germ cell expression of Fas in patients with postmeiotic germ cell arrest suggests that the Fas/FasL system may be involved in the quality control mechanism of the produced gametes. PMID:10946867

  12. Identification of the Functions of Liver X Receptor-β in Sertoli Cells Using a Targeted Expression-Rescue Model.

    PubMed

    Maqdasy, Salwan; El Hajjaji, Fatim-Zohra; Baptissart, Marine; Viennois, Emilie; Oumeddour, Abdelkader; Brugnon, Florence; Trousson, Amalia; Tauveron, Igor; Volle, David; Lobaccaro, Jean-Marc A; Baron, Silvère

    2015-12-01

    Liver X receptors (LXRs) are key regulators of lipid homeostasis and are involved in multiple testicular functions. The Lxrα(-/-);Lxrβ(-/-) mice have illuminated the roles of both isoforms in maintenance of the epithelium in the seminiferous tubules, spermatogenesis, and T production. The requirement for LXRβ in Sertoli cells have been emphasized by early abnormal cholesteryl ester accumulation in the Lxrβ(-/-) and Lxrα(-/-);Lxrβ(-/-) mice. Other phenotypes, such as germ cell loss and hypogonadism, occur later in life in the Lxrα(-/-);Lxrβ(-/-) mice. Thus, LXRβ expression in Sertoli cells seems to be essential for normal testicular physiology. To decipher the roles of LXRβ within the Sertoli cells, we generated Lxrα(-/-);Lxrβ(-/-):AMH-Lxrβ transgenic mice, which reexpress Lxrβ in Sertoli cells in the context of Lxrα(-/-);Lxrβ(-/-) mice. In addition to lipid homeostasis, LXRβ is necessary for maintaining the blood-testis barrier and the integrity of the germ cell epithelium. LXRβ is also implicated in the paracrine action of Sertoli cells on Leydig cells to modulate T synthesis. The Lxrα(-/-);Lxrβ(-/-) and Lxrα(-/-);Lxrβ(-/-):AMH-Lxrβ mice exhibit lipid accumulation in germ cells after the Abcg8 down-regulation, suggesting an intricate LXRβ-dependent cooperation between the Sertoli cells and germ cells to ensure spermiogenesis. Further analysis revealed also peritubular smooth muscle defects (abnormal lipid accumulation and disorganized smooth muscle actin) and spermatozoa stagnation in the seminiferous tubules. Together the present work elucidates specific roles of LXRβ in Sertoli cell physiology in vivo beyond lipid homeostasis. PMID:26402841

  13. Foxp3 expression in human cancer cells

    PubMed Central

    Karanikas, Vaios; Speletas, Matthaios; Zamanakou, Maria; Kalala, Fani; Loules, Gedeon; Kerenidi, Theodora; Barda, Angeliki K; Gourgoulianis, Konstantinos I; Germenis, Anastasios E

    2008-01-01

    Objective Transcription factor forkhead box protein 3 (Foxp3) specifically characterizes the thymically derived naturally occurring regulatory T cells (Tregs). Limited evidence indicates that it is also expressed, albeit to a lesser extent, in tissues other than thymus and spleen, while, very recently, it was shown that Foxp3 is expressed by pancreatic carcinoma. This study was scheduled to investigate whether expression of Foxp3 transcripts and mature protein occurs constitutively in various tumor types. Materials and methods Twenty five tumor cell lines of different tissue origins (lung cancer, colon cancer, breast cancer, melanoma, erythroid leukemia, acute T-cell leukemia) were studied. Detection of Foxp3 mRNA was performed using both conventional RT-PCR and quantitative real-time PCR while protein expression was assessed by immunocytochemistry and flow cytometry, using different antibody clones. Results Foxp3 mRNA as well as Foxp3 protein was detected in all tumor cell lines, albeit in variable levels, not related to the tissue of origin. This expression correlated with the expression levels of IL-10 and TGFb1. Conclusion We offer evidence that Foxp3 expression, characterizes tumor cells of various tissue origins. The biological significance of these findings warrants further investigation in the context of tumor immune escape, and especially under the light of current anti-cancer efforts interfering with Foxp3 expression. PMID:18430198

  14. Decorin expression in quiescent myogenic cells

    SciTech Connect

    Nishimura, Takanori Nozu, Kenjiro; Kishioka, Yasuhiro; Wakamatsu, Jun-ichi; Hattori, Akihito

    2008-06-06

    Satellite cells are quiescent muscle stem cells that promote postnatal muscle growth and repair. When satellite cells are activated by myotrauma, they proliferate, migrate, differentiate, and ultimately fuse to existing myofibers. The remainder of these cells do not differentiate, but instead return to quiescence and remain in a quiescent state until activation begins the process again. This ability to maintain their own population is important for skeletal muscle to maintain the capability to repair during postnatal life. However, the mechanisms by which satellite cells return to quiescence and maintain the quiescent state are still unclear. Here, we demonstrated that decorin mRNA expression was high in cell cultures containing a higher ratio of quiescent satellite cells when satellite cells were stimulated with various concentrations of hepatocyte growth factor. This result suggests that quiescent satellite cells express decorin at a high level compared to activated satellite cells. Furthermore, we examined the expression of decorin in reserve cells, which were undifferentiated myoblasts remaining after induction of differentiation by serum-deprivation. Decorin mRNA levels in reserve cells were higher than those in differentiated myotubes and growing myoblasts. These results suggest that decorin participates in the quiescence of myogenic cells.

  15. Vertebrate Cells Express Protozoan Antigen after Hybridization

    NASA Astrophysics Data System (ADS)

    Crane, Mark St. J.; Dvorak, James A.

    1980-04-01

    Epimastigotes, the invertebrate host stage of Trypanosoma cruzi, the protozoan parasite causing Chagas' disease in man, were fused with vertebrate cells by using polyethylene glycol. Hybrid cells were selected on the basis of T. cruzi DNA complementation of biochemical deficiencies in the vertebrate cells. Some clones of the hybrid cells expressed T. cruzi-specific antigen. It might be possible to use selected antigens obtained from the hybrids as vaccines for immunodiagnosis or for elucidation of the pathogenesis of Chagas' disease.

  16. Imaging gene expression in single living cells

    PubMed Central

    Shav-Tal, Yaron; Singer, Robert H.; Darzacq, Xavier

    2016-01-01

    Technical advances in the field of live-cell imaging have introduced the cell biologist to a new, dynamic, subcellular world. The static world of molecules in fixed cells has now been extended to the time dimension. This allows the visualization and quantification of gene expression and intracellular trafficking events of the studied molecules and the associated enzymatic processes in individual cells, in real time. PMID:15459666

  17. The expression profiles of fibroblast growth factor 9 and its receptors in developing mice testes.

    PubMed

    Lai, Meng-Shao; Wang, Chia-Yih; Yang, Shang-Hsun; Wu, Chia-Ching; Sun, H Sunny; Tsai, Shaw-Jenq; Chuang, Jih-Ing; Chen, Yung-Chia; Huang, Bu-Miin

    2016-04-01

    An expressional lack of fibroblast growth factor 9 (FGF9) would cause male-to-female sex reversal in the mouse, implying the essential role of FGF9 in testicular organogenesis and maturation. However, the temporal expression of FGF9 and its receptors during testicular development remains elusive. In this study, immunohistochemistry was used to identify the localization of FGF9 and its receptors at different embryonic and postnatal stages in mice testes. Results showed that FGF9 continuously expressed in the testis during development. FGF9 had highest expression in the interstitial region at 17-18 d post coitum (dpc) and in the spermatocytes, spermatids and Leydig cell on postnatal days (pnd) 35-65. Regarding receptor expression, FGFR1 and FGFR4 were evenly expressed in the whole testis during the embryonic and postnatal stages. However, FGFR2 and FGFR3 were widely expressed during the embryonic testis development with higher FGFR2 expression in seminiferous tubules at 16-18 dpc and higher FGFR3 expression in interstitial region at 17-18 dpc. In postnatal stage, FGFR2 extensively expressed with higher expression at spermatids and Leydig cells on 35-65 pnd and FGFR3 widely expressed in the whole testis. Taken together, these results strongly suggest that FGF9 is correlated with the temporal expression profiles of FGFR2 and FGFR3 and possibly associated with testis development. PMID:27078042

  18. Fundamentals of Expression in Mammalian Cells.

    PubMed

    Dyson, Michael R

    2016-01-01

    Expression of proteins in mammalian cells is a key technology important for many functional studies on human and higher eukaryotic genes. Studies include the mapping of protein interactions, solving protein structure by crystallization and X-ray diffraction or solution phase NMR and the generation of antibodies to enable a range of studies to be performed including protein detection in vivo. In addition the production of therapeutic proteins and antibodies, now a multi billion dollar industry, has driven major advances in cell line engineering for the production of grams per liter of active proteins and antibodies. Here the key factors that need to be considered for successful expression in HEK293 and CHO cells are reviewed including host cells, expression vector design, transient transfection methods, stable cell line generation and cultivation conditions. PMID:27165328

  19. A Cell-Autonomous Molecular Cascade Initiated by AMP-Activated Protein Kinase Represses Steroidogenesis

    PubMed Central

    Abdou, Houssein S.; Bergeron, Francis

    2014-01-01

    Steroid hormones regulate essential physiological processes, and inadequate levels are associated with various pathological conditions. In testosterone-producing Leydig cells, steroidogenesis is strongly stimulated by luteinizing hormone (LH) via its receptor leading to increased cyclic AMP (cAMP) production and expression of the steroidogenic acute regulatory (STAR) protein, which is essential for the initiation of steroidogenesis. Steroidogenesis then passively decreases with the degradation of cAMP into AMP by phosphodiesterases. In this study, we show that AMP-activated protein kinase (AMPK) is activated following cAMP-to-AMP breakdown in MA-10 and MLTC-1 Leydig cells. Activated AMPK then actively inhibits cAMP-induced steroidogenesis by repressing the expression of key regulators of steroidogenesis, including Star and Nr4a1. Similar results were obtained in Y-1 adrenal cells and in the constitutively steroidogenic R2C cells. We have also determined that maximum AMPK activation following stimulation of steroidogenesis in MA-10 Leydig cells occurs when steroid hormone production has reached a plateau. Our data identify AMPK as a molecular rheostat that actively represses steroid hormone biosynthesis to preserve cellular energy homeostasis and prevent excess steroid production. PMID:25225331

  20. B cell receptor accessory molecule CD79α: characterisation and expression analysis in a cartilaginous fish, the spiny dogfish (Squalus acanthias).

    PubMed

    Li, Ronggai; Wang, Tiehui; Bird, Steve; Zou, Jun; Dooley, Helen; Secombes, Christopher J

    2013-06-01

    CD79α (also known as Igα) is a component of the B cell antigen receptor complex and plays an important role in B cell signalling. The CD79α protein is present on the surface of B cells throughout their life cycle, and is absent on all other healthy cells, making it a highly reliable marker for B cells in mammals. In this study the spiny dogfish (Squalus acanthias) CD79α (SaCD79α) is described and its expression studied under constitutive and stimulated conditions. The spiny dogfish CD79α cDNA contains an open reading frame of 618 bp, encoding a protein of 205 amino acids. Comparison of the SaCD79α gene with that of other species shows that the gross structure (number of exons, exon/intron boundaries, etc.) is highly conserved across phylogeny. Additionally, analysis of the 5' flanking region shows SaCD79α lacks a TATA box and possesses binding sites for multiple transcription factors implicated in its B cell-specific gene transcription in other species. Spiny dogfish CD79α is most highly expressed in immune tissues, such as spleen, epigonal and Leydig organ, and its transcript level significantly correlates with those of spiny dogfish immunoglobulin heavy chains. Additionally, CD79α transcription is up-regulated, to a small but significant degree, in peripheral blood cells following stimulation with pokeweed mitogen. These results strongly indicate that, as in mammals, spiny dogfish CD79α is expressed by shark B cells where it associates with surface-bound immunoglobulin to form a fully functional BCR, and thus may serve as a pan-B cell marker in future shark immunological studies. PMID:23454429

  1. CD43 expression in B cell lymphoma.

    PubMed Central

    Treasure, J.; Lane, A.; Jones, D. B.; Wright, D. H.

    1992-01-01

    AIMS: To determine the expression of CD43 in frozen sections in a range of B cell lymphomas. METHODS: The monoclonal antibody WR14, clustered provisionally in the Fourth Leucocyte Typing Workshop as a CD43 reagent, was investigated by epitope blocking studies on formalin fixed reactive lymph node tissue, using the established CD43 antibody MT1, to validate its use as a CD43 reagent. CD43 expression was studied in 131 immunophenotypically defined B cell lymphomas, including lymphocytic lymphoma (Lc, n = 13), centrocytic lymphoma (Cc, n = 14), and a range of follicle centre cell lymphomas (FCC) including centroblastic/centrocytic follicular (CbCcF, n = 48), centroblastic diffuse (CbD, n = 39), centroblastic/centrocytic diffuse (CbCcD, n = 4), centroblastic follicular and diffuse (Cb FD, n = 3) and centroblastic/centrocytic follicular and diffuse (CbCc FD, n = 1). Nine lymphomas of mucosa associated lymphoid tissue (MALT) were also examined. RESULTS: Epitope blocking studies showed that WR14 is a CD43 reagent that binds to an epitope identical with or close to that recognised by MT1. Eleven of 13 (84%) cases of Lc and 11 of 14 (78%) cases of Cc expressed CD43; 87 of 95 (91%) cases of FCC did not. All eight low grade lymphomas of MALT were negative. One high grade lymphoma, transformed from a low grade MALT lymphoma, was positive for CD43. The expression of CD43 by tumours of B cell lineage was associated with the expression of CD5 (p < 0.001) although either antigen could occasionally be found in the absence of the other. CONCLUSION: CD43 reagents can be used in conjunction with CD5 antibodies for the immunophenotypic discrimination of follicle centre cell lymphomas from non-follicle centre cell lymphomas. Images PMID:1280654

  2. Dental enamel cells express functional SOCE channels

    PubMed Central

    Nurbaeva, Meerim K.; Eckstein, Miriam; Concepcion, Axel R.; Smith, Charles E.; Srikanth, Sonal; Paine, Michael L.; Gwack, Yousang; Hubbard, Michael J.; Feske, Stefan; Lacruz, Rodrigo S.

    2015-01-01

    Dental enamel formation requires large quantities of Ca2+ yet the mechanisms mediating Ca2+ dynamics in enamel cells are unclear. Store-operated Ca2+ entry (SOCE) channels are important Ca2+ influx mechanisms in many cells. SOCE involves release of Ca2+ from intracellular pools followed by Ca2+ entry. The best-characterized SOCE channels are the Ca2+ release-activated Ca2+ (CRAC) channels. As patients with mutations in the CRAC channel genes STIM1 and ORAI1 show abnormal enamel mineralization, we hypothesized that CRAC channels might be an important Ca2+ uptake mechanism in enamel cells. Investigating primary murine enamel cells, we found that key components of CRAC channels (ORAI1, ORAI2, ORAI3, STIM1, STIM2) were expressed and most abundant during the maturation stage of enamel development. Furthermore, inositol 1,4,5-trisphosphate receptor (IP3R) but not ryanodine receptor (RyR) expression was high in enamel cells suggesting that IP3Rs are the main ER Ca2+ release mechanism. Passive depletion of ER Ca2+ stores with thapsigargin resulted in a significant raise in [Ca2+]i consistent with SOCE. In cells pre-treated with the CRAC channel blocker Synta-66 Ca2+ entry was significantly inhibited. These data demonstrate that enamel cells have SOCE mediated by CRAC channels and implicate them as a mechanism for Ca2+ uptake in enamel formation. PMID:26515404

  3. Cell cycle gene expression under clinorotation

    NASA Astrophysics Data System (ADS)

    Artemenko, Olga

    2016-07-01

    Cyclins and cyclin-dependent kinase (CDK) are main regulators of the cell cycle of eukaryotes. It's assumes a significant change of their level in cells under microgravity conditions and by other physical factors actions. The clinorotation use enables to determine the influence of gravity on simulated events in the cell during the cell cycle - exit from the state of quiet stage and promotion presynthetic phase (G1) and DNA synthesis phase (S) of the cell cycle. For the clinorotation effect study on cell proliferation activity is the necessary studies of molecular mechanisms of cell cycle regulation and development of plants under altered gravity condition. The activity of cyclin D, which is responsible for the events of the cell cycle in presynthetic phase can be controlled by the action of endogenous as well as exogenous factors, but clinorotation is one of the factors that influence on genes expression that regulate the cell cycle.These data can be used as a model for further research of cyclin - CDK complex for study of molecular mechanisms regulation of growth and proliferation. In this investigation we tried to summarize and analyze known literature and own data we obtained relatively the main regulators of the cell cycle in altered gravity condition.

  4. Complex expression patterns of lymphocyte-specific genes during the development of cartilaginous fish implicate unique lymphoid tissues in generating an immune repertoire

    NASA Technical Reports Server (NTRS)

    Miracle, A. L.; Anderson, M. K.; Litman, R. T.; Walsh, C. J.; Luer, C. A.; Rothenberg, E. V.; Litman, G. W.

    2001-01-01

    Cartilaginous fish express canonical B and T cell recognition genes, but their lymphoid organs and lymphocyte development have been poorly defined. Here, the expression of Ig, TCR, recombination-activating gene (Rag)-1 and terminal deoxynucleosidase (TdT) genes has been used to identify roles of various lymphoid tissues throughout development in the cartilaginous fish, Raja eglanteria (clearnose skate). In embryogenesis, Ig and TCR genes are sharply up-regulated at 8 weeks of development. At this stage TCR and TdT expression is limited to the thymus; later, TCR gene expression appears in peripheral sites in hatchlings and adults, suggesting that the thymus is a source of T cells as in mammals. B cell gene expression indicates more complex roles for the spleen and two special organs of cartilaginous fish-the Leydig and epigonal (gonad-associated) organs. In the adult, the Leydig organ is the site of the highest IgM and IgX expression. However, the spleen is the first site of IgM expression, while IgX is expressed first in gonad, liver, Leydig and even thymus. Distinctive spatiotemporal patterns of Ig light chain gene expression also are seen. A subset of Ig genes is pre-rearranged in the germline of the cartilaginous fish, making expression possible without rearrangement. To assess whether this allows differential developmental regulation, IgM and IgX heavy chain cDNA sequences from specific tissues and developmental stages have been compared with known germline-joined genomic sequences. Both non-productively rearranged genes and germline-joined genes are transcribed in the embryo and hatchling, but not in the adult.

  5. Colony stimulating factor 1 is an extrinsic stimulator of mouse spermatogonial stem cell self-renewal

    PubMed Central

    Oatley, Jon M.; Oatley, Melissa J.; Avarbock, Mary R.; Tobias, John W.; Brinster, Ralph L.

    2009-01-01

    Summary Self-renewal and differentiation of spermatogonial stem cells (SSCs) provide the foundation for testis homeostasis, yet mechanisms that control their functions in mammals are poorly defined. We used microarray transcript profiling to identify specific genes whose expressions are augmented in the SSC-enriched Thy1+ germ cell fraction of mouse pup testes. Comparisons of gene expression in the Thy1+ germ cell fraction with the Thy1-depleted testis cell population identified 202 genes that are expressed 10-fold or higher in Thy1+ cells. This database provided a mining tool to investigate specific characteristics of SSCs and identify novel mechanisms that potentially influence their functions. These analyses revealed that colony stimulating factor 1 receptor (Csf1r) gene expression is enriched in Thy1+ germ cells. Addition of recombinant colony stimulating factor 1 (Csf1), the specific ligand for Csf1r, to culture media significantly enhanced the self-renewal of SSCs in heterogeneous Thy1+ spermatogonial cultures over a 63-day period without affecting total germ cell expansion. In vivo, expression of Csf1 in both pre-pubertal and adult testes was localized to clusters of Leydig cells and select peritubular myoid cells. Collectively, these results identify Csf1 as an extrinsic stimulator of SSC self-renewal and implicate Leydig and myoid cells as contributors of the testicular stem cell niche in mammals. PMID:19270176

  6. Differential expression of aromatase, estrogen receptor alpha and 17β-HSD associated with the processes of total testicular regression and recrudescence in the bat Myotis nigricans (Chiroptera: Vespertilionidae).

    PubMed

    Beguelini, Mateus R; Falleiros, Luiz R; Góes, Rejane M; Rahal, Paula; Morielle-Versute, Eliana; Taboga, Sebastião R

    2014-05-15

    Despite the worldwide distribution and many unique reproductive adaptations that bats present, many aspects of their reproductive hormonal regulation have not been adequately studied, especially in species that presented patterns of total testicular regression. Thus, this study aimed to evaluate the testicular expression of 17β-HSD type 1, aromatase and ERα in the bat Myotis nigricans, during the four periods of its reproductive cycle. Immunoreactivity for ERα was detected only in the cytoplasm of elongated spermatids and in the nuclei of spermatogonia and Sertoli cells. Expression of aromatase was observed in round and elongated spermatids and in Sertoli and Leydig cells. Immunoreactivity for 17β-HSD was restricted to the cytoplasm of Leydig cells. The three expression patterns varied significantly during the four periods of the reproductive cycle. Expression of ERα and aromatase in spermatids was continuous, while expression of ERα in spermatogonia occurred only in initial types (Ap). Expression of ERα and aromatase in Sertoli cells varied, with expression only in periods of spermatogenetic activities; and the same variation was observed for the expression of aromatase and 17β-HSD in Leydig cells. We, therefore, propose that the processes of total testicular regression and posterior recrudescence suffered by M. nigricans from September to January in the northwest of the São Paulo State of Brazil, are directly regulated by testosterone and estrogen. This occurs via the production of testosterone by 17β-HSD, its conversion into estrogen by aromatase, and activation/deactivation of Sertoli cells' AR and spermatogonia's ERα. PMID:24726986

  7. Cytotoxic effect of nanosilver particles on testicular tissue: Evidence for biochemical stress and Hsp70-2 protein expression.

    PubMed

    Rezazadeh-Reyhani, Zari; Razi, Mazdak; Malekinejad, Hassan; Sadrkhanlou, Rajabali

    2015-09-01

    Lastly, there are growing evidences that nanosilver (NS) particles highly induce cytotoxic impacts in vitro and in vivo. Here, we analyzed the dose dependent effect of NS on histological changes, biochemical alterations and endocrine statuses, sperm parameters as well as chaperone Hsp70-2 expression. NS particles (50-60nm) were administrated in 3 doses of 0.5, 1 and 5mg/kg, intraperitoneally, for 35 days. The 0.3mL normal saline was administrated in control-sham group. Histological alterations, sperm parameters, serum levels of LH, FSH and testosterone were evaluated. Germinal and Leydig cells RNA damage, Leydig cells steroidogenic foci, the testicular and sperm total antioxidant capacity (TAC), malondialdehyde (MDA), nitric oxide (NO) levels, immunohistochemical (IHC) expression and mRNA level of Hsp70-2 were analyzed. The NS, dose dependently, resulted in enhanced germinal cells degeneration, necrosis, seminiferous tubules atrophy and decreased serum levels of LH, FSH and testosterone. Elevated germinal and Leydig cells RNA damage associated with increased sperm abnormalities were observed in NS-treated groups. Expression of Hsp70-2 was up-regulated in 0.5mg/kg, while its expression was decreased in 1 and 5mg/kg NS-treated groups. Testicular and sperm TAC levels reduced. However, the MDA and NO levels significantly (P<0.05) increased in all NS-treated groups. No histological and biochemical changes were detected in control-sham group. In conclusion, the NS particles exert their pathological impact via affecting testicular antioxidant and endocrine statuses, which in turn lead to diminished expression of Hsp70-2. Ultimately, by this mechanism NS particles adversely impact the cellular RNA, DNA and protein contents. PMID:26363132

  8. Expression of bacterial genes in plant cells.

    PubMed Central

    Fraley, R T; Rogers, S G; Horsch, R B; Sanders, P R; Flick, J S; Adams, S P; Bittner, M L; Brand, L A; Fink, C L; Fry, J S; Galluppi, G R; Goldberg, S B; Hoffmann, N L; Woo, S C

    1983-01-01

    Chimeric bacterial genes conferring resistance to aminoglycoside antibiotics have been inserted into the Agrobacterium tumefaciens tumor-inducing (Ti) plasmid and introduced into plant cells by in vitro transformation techniques. The chimeric genes contain the nopaline synthase 5' and 3' regulatory regions joined to the genes for neomycin phosphotransferase type I or type II. The chimeric genes were cloned into an intermediate vector, pMON120, and inserted into pTiB6S3 by recombination and then introduced into petunia and tobacco cells by cocultivating A. tumefaciens cells with protoplast-derived cells. Southern hybridization was used to confirm the presence of the chimeric genes in the transformed plant tissues. Expression of the chimeric genes was determined by the ability of the transformed cells to proliferate on medium containing normally inhibitory levels of kanamycin (50 micrograms/ml) or other aminoglycoside antibiotics. Plant cells transformed by wild-type pTiB6S3 or derivatives carrying the bacterial neomycin phosphotransferase genes with their own promoters failed to grow under these conditions. The significance of these results for plant genetic engineering is discussed. Images PMID:6308651

  9. Notch signaling represses GATA4-induced expression of genes involved in steroid biosynthesis.

    PubMed

    George, Rajani M; Hahn, Katherine L; Rawls, Alan; Viger, Robert S; Wilson-Rawls, Jeanne

    2015-10-01

    Notch2 and Notch3 and genes of the Notch signaling network are dynamically expressed in developing follicles, where they are essential for granulosa cell proliferation and meiotic maturation. Notch receptors, ligands, and downstream effector genes are also expressed in testicular Leydig cells, predicting a potential role in regulating steroidogenesis. In this study, we sought to determine if Notch signaling in small follicles regulates the proliferation response of granulosa cells to FSH and represses the up-regulation steroidogenic gene expression that occurs in response to FSH as the follicle grows. Inhibition of Notch signaling in small preantral follicles led to the up-regulation of the expression of genes in the steroid biosynthetic pathway. Similarly, progesterone secretion by MA-10 Leydig cells was significantly inhibited by constitutively active Notch. Together, these data indicated that Notch signaling inhibits steroidogenesis. GATA4 has been shown to be a positive regulator of steroidogenic genes, including STAR protein, P450 aromatase, and 3B-hydroxysteroid dehydrogenase. We observed that Notch downstream effectors HEY1, HEY2, and HEYL are able to differentially regulate these GATA4-dependent promoters. These data are supported by the presence of HEY/HES binding sites in these promoters. These studies indicate that Notch signaling has a role in the complex regulation of the steroidogenic pathway. PMID:26183893

  10. ISOLATION AND CULTURE OF LEYDIG CELLS FROM ADULT RATS

    EPA Science Inventory

    Testosterone is essential for quantitatively normal sperm production in the testis, normal sperm maturation in the epididymis, maintenance of the accessory sex organs, and effective sexual behavior. ariety of xenobiotics can result in a significant decrease in spermatogenesis, sp...

  11. Gene expression profiles in irradiated cancer cells

    NASA Astrophysics Data System (ADS)

    Minafra, L.; Bravatà, V.; Russo, G.; Ripamonti, M.; Gilardi, M. C.

    2013-07-01

    Knowledge of the molecular and genetic mechanisms underlying cellular response to radiation may provide new avenues to develop innovative predictive tests of radiosensitivity of tumours and normal tissues and to improve individual therapy. Nowadays very few studies describe molecular changes induced by hadrontherapy treatments, therefore this field has to be explored and clarified. High-throughput methodologies, such as DNA microarray, allow us to analyse mRNA expression of thousands of genes simultaneously in order to discover new genes and pathways as targets of response to hadrontherapy. Our aim is to elucidate the molecular networks involved in the sensitivity/resistance of cancer cell lines subjected to hadrontherapy treatments with a genomewide approach by using cDNA microarray technology to identify gene expression profiles and candidate genes responsible of differential cellular responses.

  12. Gene expression profiles in irradiated cancer cells

    SciTech Connect

    Minafra, L.; Bravatà, V.; Russo, G.; Ripamonti, M.; Gilardi, M. C.

    2013-07-26

    Knowledge of the molecular and genetic mechanisms underlying cellular response to radiation may provide new avenues to develop innovative predictive tests of radiosensitivity of tumours and normal tissues and to improve individual therapy. Nowadays very few studies describe molecular changes induced by hadrontherapy treatments, therefore this field has to be explored and clarified. High-throughput methodologies, such as DNA microarray, allow us to analyse mRNA expression of thousands of genes simultaneously in order to discover new genes and pathways as targets of response to hadrontherapy. Our aim is to elucidate the molecular networks involved in the sensitivity/resistance of cancer cell lines subjected to hadrontherapy treatments with a genomewide approach by using cDNA microarray technology to identify gene expression profiles and candidate genes responsible of differential cellular responses.

  13. Gene Expression by Mouse Inner Ear Hair Cells during Development

    PubMed Central

    Scheffer, Déborah I.; Shen, Jun

    2015-01-01

    Hair cells of the inner ear are essential for hearing and balance. As a consequence, pathogenic variants in genes specifically expressed in hair cells often cause hereditary deafness. Hair cells are few in number and not easily isolated from the adjacent supporting cells, so the biochemistry and molecular biology of hair cells can be difficult to study. To study gene expression in hair cells, we developed a protocol for hair cell isolation by FACS. With nearly pure hair cells and surrounding cells, from cochlea and utricle and from E16 to P7, we performed a comprehensive cell type-specific RNA-Seq study of gene expression during mouse inner ear development. Expression profiling revealed new hair cell genes with distinct expression patterns: some are specific for vestibular hair cells, others for cochlear hair cells, and some are expressed just before or after maturation of mechanosensitivity. We found that many of the known hereditary deafness genes are much more highly expressed in hair cells than surrounding cells, suggesting that genes preferentially expressed in hair cells are good candidates for unknown deafness genes. PMID:25904789

  14. T cells stimulate catabolic gene expression by the stromal cells from giant cell tumor of bone

    SciTech Connect

    Cowan, Robert W.; Ghert, Michelle; Singh, Gurmit

    2012-03-23

    Highlights: Black-Right-Pointing-Pointer Two T cell lines stimulate PTHrP, RANKL, MMP13 gene expression in GCT cell cultures. Black-Right-Pointing-Pointer CD40 expressed by stromal cells; CD40L detected in whole tumor but not cultures. Black-Right-Pointing-Pointer Effect of CD40L treatment on GCT cells increased PTHrP and MMP13 gene expression. Black-Right-Pointing-Pointer PTHrP treatment increased MMP13 expression, while inhibition decreased expression. Black-Right-Pointing-Pointer T cells may stimulate GCT stromal cells and promote the osteolysis of the tumor. -- Abstract: The factors that promote the localized bone resorption by giant cell tumor of bone (GCT) are not fully understood. We investigated whether T cells could contribute to bone resorption by stimulating expression of genes for parathyroid hormone-related protein (PTHrP), matrix metalloproteinase (MMP)-13, and the receptor activator of nuclear-factor {kappa}B ligand (RANKL). Two cell lines, Jurkat clone E6-1 and D1.1, were co-cultured with isolated GCT stromal cells. Real-time PCR analyses demonstrated a significant increase of all three genes following 48 h incubation, and PTHrP and MMP-13 gene expression was also increased at 24 h. Further, we examined the expression of CD40 ligand (CD40L), a protein expressed by activated T cells, and its receptor, CD40, in GCT. Immunohistochemistry results revealed expression of the CD40 receptor in both the stromal cells and giant cells of the tumor. RNA collected from whole GCT tissues showed expression of CD40LG, which was absent in cultured stromal cells, and suggests that CD40L is expressed within GCT. Stimulation of GCT stromal cells with CD40L significantly increased expression of the PTHrP and MMP-13 genes. Moreover, we show that inhibition of PTHrP with neutralizing antibodies significantly decreased MMP13 expression by the stromal cells compared to IgG-matched controls, whereas stimulation with PTHrP (1-34) increased MMP-13 gene expression. These

  15. Murine somatic cell nuclear transfer using reprogrammed donor cells expressing male germ cell-specific genes.

    PubMed

    Kang, Hoin; Park, Jong Im; Roh, Sangho

    2016-01-01

    In vivo-matured mouse oocytes were enucleated, and a single murine embryonic fibroblast (control or reprogrammed by introducing extracts from murine testis tissue, which showed expression of male germ cell-specific genes) was injected into the cytoplasm of the oocytes. The rate of blastocyst development and expression levels of Oct-4, Eomes and Cdx-2 were not significantly different in both experimental groups. However, the expression levels of Nanog, Sox9 and Glut-1 were significantly increased when reprogrammed cells were used as donor nuclei. Increased expression of Nanog can be supportive of complete reprogramming of somatic cell nuclear transfer murine embryos. The present study suggested that donor cells expressing male germ cell-specific genes can be reconstructed and can develop into embryos with normal high expression of developmentally essential genes. PMID:26369430

  16. Global gene expression analyses of hematopoietic stem cell-like cell lines with inducible Lhx2 expression

    PubMed Central

    Richter, Karin; Wirta, Valtteri; Dahl, Lina; Bruce, Sara; Lundeberg, Joakim; Carlsson, Leif; Williams, Cecilia

    2006-01-01

    Background Expression of the LIM-homeobox gene Lhx2 in murine hematopoietic cells allows for the generation of hematopoietic stem cell (HSC)-like cell lines. To address the molecular basis of Lhx2 function, we generated HSC-like cell lines where Lhx2 expression is regulated by a tet-on system and hence dependent on the presence of doxycyclin (dox). These cell lines efficiently down-regulate Lhx2 expression upon dox withdrawal leading to a rapid differentiation into various myeloid cell types. Results Global gene expression of these cell lines cultured in dox was compared to different time points after dox withdrawal using microarray technology. We identified 267 differentially expressed genes. The majority of the genes overlapping with HSC-specific databases were those down-regulated after turning off Lhx2 expression and a majority of the genes overlapping with those defined as late progenitor-specific genes were the up-regulated genes, suggesting that these cell lines represent a relevant model system for normal HSCs also at the level of global gene expression. Moreover, in situ hybridisations of several genes down-regulated after dox withdrawal showed overlapping expression patterns with Lhx2 in various tissues during embryonic development. Conclusion Global gene expression analysis of HSC-like cell lines with inducible Lhx2 expression has identified genes putatively linked to self-renewal / differentiation of HSCs, and function of Lhx2 in organ development and stem / progenitor cells of non-hematopoietic origin. PMID:16600034

  17. Expression and function of ryanodine receptors in nonexcitable cells.

    PubMed

    Bennett, D L; Cheek, T R; Berridge, M J; De Smedt, H; Parys, J B; Missiaen, L; Bootman, M D

    1996-03-15

    We have used reverse transcriptase-polymerase chain reaction to investigate the expression of ryanodine receptors in several excitable and nonexcitable cell types. Consistent with previous reports, we detected ryanodine receptor expression in brain, heart, and skeletal muscle. In addition, we detected ryanodine receptor expression in various other excitable cells including PC 12 and A7r5 cells. Several muscle cell lines (BC3H1, C2C12, L6, and Sol8) weakly expressed ryanodine receptor when undifferentiated but strongly expressed type 1 and type 3 ryanodine receptor isoforms when differentiated into a muscle phenotype. Only 2 (HeLa and LLC-PK1 cells) out of 11 nonexcitable cell types examined expressed ryanodine receptors. Expression of ryanodine receptors at the protein level in these cells was confirmed using [3H]ryanodine binding. We also investigated the function of ryanodine receptors in Ca2+ signaling in HeLa cells using single-cell Fura-2 imaging. Neither caffeine nor ryanodine caused a detectable elevation of cytoplasmic Ca2+ in single HeLa cells. However, ryanodine caused a significant decrease in the amplitude of Ca 2+ signals evoked by repetitive stimulation with ATP. These studies show that ryanodine receptors are expressed in some nonexcitable cell types and furthermore suggest that the ryanodine receptors may be involved in a subtle regulation of intracellular Ca2+ responses. PMID:8626432

  18. Systematic characterization of lncRNAs' cell-to-cell expression heterogeneity in glioblastoma cells

    PubMed Central

    Dong, Jun; Zhuang, Yan; Huang, Shuyu; Ma, Binbin; Chen, Puxiang; Li, Xiaodong; Zhang, Bo; Li, Zhiguang; Jin, Bilian

    2016-01-01

    Glioblastoma (GBM) is the most common malignant adult brain tumor generally associated with high level of cellular heterogeneity and a dismal prognosis. Long noncoding RNAs (lncRNAs) are emerging as novel mediators of tumorigenesis. Recently developed single-cell RNA-seq provides an unprecedented way for analysis of the cell-to-cell variability in lncRNA expression profiles. Here we comprehensively examined the expression patterns of 2,003 lncRNAs in 380 cells from five primary GBMs and two glioblastoma stem-like cell (GSC) lines. Employing the self-organizing maps, we displayed the landscape of the lncRNA expression dynamics for individual cells. Further analyses revealed heterogeneous nature of lncRNA in abundance and splicing patterns. Moreover, lncRNA expression variation is also ubiquitously present in the established GSC lines composed of seemingly identical cells. Through comparative analysis of GSC and corresponding differentiated cell cultures, we defined a stemness signature by the set of 31 differentially expressed lncRNAs, which can disclose stemness gradients in five tumors. Additionally, based on known classifier lncRNAs for molecular subtypes, each tumor was found to comprise individual cells representing four subtypes. Our systematic characterization of lncRNA expression heterogeneity lays the foundation for future efforts to further understand the function of lncRNA, develop valuable biomarkers, and enhance knowledge of GBM biology. PMID:26918340

  19. Probing cell-free gene expression noise in femtoliter volumes

    SciTech Connect

    Karig, David K; Jung, Seung-Yong; Srijanto, Bernadeta R; Collier, Pat; Simpson, Michael L

    2013-01-01

    Cell-free systems offer a simplified and flexible context that enables important biological reactions while removing complicating factors such as fitness, division, and mutation that are associated with living cells. However, cell-free expression in unconfined spaces is missing important elements of expression in living cells. In particular, the small volume of living cells can give rise to significant stochastic effects, which are negligible in bulk cell-free reactions. Here, we confine cell-free gene expression reactions to cell relevant 20 fL volumes (between the volumes of E. coli and S. cerevisiae), in polydimethylsiloxane (PDMS) containers. We demonstrate that expression efficiency varies widely at this volume, and we analyze gene expression noise. Noise analysis reveals signatures of translational bursting while noise dynamics suggest that overall cell-free expression is limited by a diminishing translation rate. In addition to offering a unique approach to understanding noise in gene circuits, our work contributes to a deeper understanding of the biophysical properties of cell-free expression systems, thus aiding efforts to harness cell-free systems for synthetic biology applications.

  20. Estradiol Upregulates c-FLIPlong Expression in Anterior Pituitary Cells.

    PubMed

    Jaita, G; Zárate, S; Ferraris, J; Gottardo, M F; Eijo, G; Magri, M L; Pisera, D; Seilicovich, A

    2016-04-01

    Anterior pituitary cell turnover depends on a tight balance between proliferation and apoptosis. We have previously shown that estrogens sensitize anterior pituitary cells to pro-apoptotic stimuli. c-FLIP (cellular-FLICE-inhibitory-protein) isoforms are regulatory proteins of apoptosis triggered by death receptors. c-FLIPshort isoform competes with procaspase-8 inhibiting its activation. However, c-FLIPlong isoform may have a pro- or anti-apoptotic function depending on its expression level. In the present study, we explored whether estrogens modulate c-FLIP expression in anterior pituitary cells from ovariectomized (OVX) rats and in GH3 cells, a somatolactotrope cell line. Acute administration of 17β-estradiol to OVX rats increased c-FLIPlong expression in the anterior pituitary gland without changing c-FLIPshort expression as assessed by Western blot. Estradiol in vitro also increased c-FLIPlong expression in anterior pituitary cells but not in GH3 cells. As determined by flow cytometry, the percentage of anterior pituitary cells expressing c-FLIP was higher than in GH3 cells. However, c-FLIP fluorescence intensity in GH3 cells was higher than in anterior pituitary cells. FasL increased the percentage of TUNEL-positive GH3 cells incubated either with or without estradiol suggesting that the pro-apoptotic action of Fas activation is estrogen-independent. Our results show that unlike what happens in nontumoral pituitary cells, estrogens do not modulate either c-FLIPlong expression or FasL-induced apoptosis in GH3 cells. The stimulatory effect of estradiol on c-FLIPlong expression could be involved in the sensitizing effect of this steroid to apoptosis in anterior pituitary cells. The absence of this estrogenic action in tumor pituitary cells could be involved in their tumor-like behavior. PMID:26566102

  1. Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

    PubMed

    Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

    2000-04-01

    Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy. PMID:10811469

  2. TOX expression in cutaneous B-cell lymphomas.

    PubMed

    Schrader, Anne M R; Jansen, Patty M; Willemze, Rein

    2016-08-01

    Thymocyte selection-associated high-mobility group box (TOX) is aberrantly expressed in cutaneous T-cell lymphomas. In a recent study, TOX expression was noted unexpectedly in the follicle center (germinal center) B-cells of reactive lymph nodes and tonsils, used as external controls. To evaluate whether TOX is also expressed by cutaneous B-cell lymphomas, TOX immunohistochemistry was performed on skin biopsies of 44 patients with primary and secondary cutaneous B-cell proliferations. TOX was expressed not only in the reactive follicle center cells of lymph nodes, tonsils, cutaneous lymphoid hyperplasia, and primary cutaneous marginal zone lymphomas, but also by the neoplastic follicle center cells of 16/17 patients with primary cutaneous follicle center lymphoma (PCFCL) and 7/7 patients with cutaneous manifestations of systemic follicular lymphoma (FL). Notably, TOX showed a very similar expression pattern as BCL6, a marker of germinal center B-cells. In 4/10 patients with a BCL6(+) primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL,LT) and in 2/2 patients with a secondary cutaneous BCL6(+) diffuse large B-cell lymphoma (DLBCL), TOX was expressed by more than 50 % of the neoplastic B-cells. In contrast, in 3/3 BCL6(-) PCDLBCL,LT, TOX was completely negative or weakly expressed by a minor proportion of the neoplastic B-cells. In conclusion, TOX is expressed not only by neoplastic T-cells, but also by both reactive and neoplastic follicle center (germinal center) B-cells and a proportion of BCL6(+) PCDLBCL,LT and secondary cutaneous BCL6(+) DLBCL. The functional significance of TOX expression in reactive and neoplastic B-cells remains to be elucidated. PMID:27180090

  3. Characteristics and EGFP expression of goat mammary gland epithelial cells.

    PubMed

    Zheng, Y-M; He, X-Y; Zhang, Y

    2010-12-01

    The aims of this study were (i) to establish a goat mammary gland epithelial (GMGE) cell line, and (ii) to determine if these GMGE cells could be maintained long-term in culture by continuous subculturing following transfection with a reporter gene, enhanced green fluorescence protein (EGFP). Primary culture of GMGE cells was achieved by outgrowth of migrating cells from the fragments of the mammary gland tissue of a lactating goat. The passage 16 GMGE cells were transfected with EGFP gene using lipofection. The expression of Cell keratins of epithelial cells in GMGE cells was test by immunofluorescence. Βeta-Casein gene mRNA was test for GMGE cells by RT-PCR. The results showed that when grown at low density on a plastic substratum, the GMGE cells formed islands, and when grown to confluency, the cells formed a monolayer and aggregated with the characteristic cobble-stone morphology of epithelial cells. GMGE cells could form dome-like structure which looked like nipple, and the lumen-like structures formed among the cells. Several blister-like structures appeared in the appearance of the cells. The GMGE cells contained different cell types, majority of the cells were short shuttle-like or polygon which were beehive-like. A part of cells were round and flat, a small number of cells were elongated. Some of the GMGE cells contained milk drops. The cell nuclei were round which had 2-4 obvious cores. The expression of Cell keratins demonstrated the property of epithelial cells in GMGE cells by immunofluorescence. The GMGE cells could express transcript encoding a Βeta-Casein protein. EGFP gene was successfully transferred into the GMGE cells, and the transfected cells could be maintained long-term in culture by continuous subculturing. In conclusion, we have established a EGFP gene transfected GMGE (ET-GMGE) cell line and maintained it long-term in culture by continuous subculturing. PMID:20113446

  4. Advantages and applications of CAR-expressing natural killer cells

    PubMed Central

    Glienke, Wolfgang; Esser, Ruth; Priesner, Christoph; Suerth, Julia D.; Schambach, Axel; Wels, Winfried S.; Grez, Manuel; Kloess, Stephan; Arseniev, Lubomir; Koehl, Ulrike

    2015-01-01

    In contrast to donor T cells, natural killer (NK) cells are known to mediate anti-cancer effects without the risk of inducing graft-versus-host disease (GvHD). In order to improve cytotoxicity against resistant cancer cells, auspicious efforts have been made with chimeric antigen receptor (CAR) expressing T- and NK cells. These CAR-modified cells express antigen receptors against tumor-associated surface antigens, thus redirecting the effector cells and enhancing tumor-specific immunosurveillance. However, many cancer antigens are also expressed on healthy tissues, potentially leading to off tumor/on target toxicity by CAR-engineered cells. In order to control such potentially severe side effects, the insertion of suicide genes into CAR-modified effectors can provide a means for efficient depletion of these cells. While CAR-expressing T cells have entered successfully clinical trials, experience with CAR-engineered NK cells is mainly restricted to pre-clinical investigations and predominantly to NK cell lines. In this review we summarize the data on CAR expressing NK cells focusing on the possible advantage using these short-lived effector cells and discuss the necessity of suicide switches. Furthermore, we address the compliance of such modified NK cells with regulatory requirements as a new field in cellular immunotherapy. PMID:25729364

  5. Transferrin receptor expression by stimulated cells in mixed lymphocyte culture.

    PubMed Central

    Salmon, M; Bacon, P A; Symmons, D P; Walton, K W

    1985-01-01

    Transferrin receptor (TRFr) expression by cells in mixed lymphocyte culture increases steadily for the first 5 days, but then reaches a plateau. By the sixth day in culture, about 20% of viable cells express TRFr in two-way mixed lymphocyte reactions. This subpopulation of TRFr-positive cells represents the proliferating population; it is heterogeneous, containing T-cell blasts and smaller cells which are a mixture of T and non-T cells. A small group of non-T cells have phenotypic similarity to natural killer (NK) cells. T cells appear to divide earlier in the course of the response than non-T cells. The biphasic nature of this response and the slower non-T reactivity may be due to a secondary stimulation of non-T cells by factors released from activated T cells (such as interleukin-2). PMID:2982734

  6. Robust Inference of Cell-to-Cell Expression Variations from Single- and K-Cell Profiling

    PubMed Central

    Narayanan, Manikandan; Martins, Andrew J.; Tsang, John S.

    2016-01-01

    Quantifying heterogeneity in gene expression among single cells can reveal information inaccessible to cell-population averaged measurements. However, the expression level of many genes in single cells fall below the detection limit of even the most sensitive technologies currently available. One proposed approach to overcome this challenge is to measure random pools of k cells (e.g., 10) to increase sensitivity, followed by computational “deconvolution” of cellular heterogeneity parameters (CHPs), such as the biological variance of single-cell expression levels. Existing approaches infer CHPs using either single-cell or k-cell data alone, and typically within a single population of cells. However, integrating both single- and k-cell data may reap additional benefits, and quantifying differences in CHPs across cell populations or conditions could reveal novel biological information. Here we present a Bayesian approach that can utilize single-cell, k-cell, or both simultaneously to infer CHPs within a single condition or their differences across two conditions. Using simulated as well as experimentally generated single- and k-cell data, we found situations where each data type would offer advantages, but using both together can improve precision and better reconcile CHP information contained in single- and k-cell data. We illustrate the utility of our approach by applying it to jointly generated single- and k-cell data to reveal CHP differences in several key inflammatory genes between resting and inflammatory cytokine-activated human macrophages, delineating differences in the distribution of ‘ON’ versus ‘OFF’ cells and in continuous variation of expression level among cells. Our approach thus offers a practical and robust framework to assess and compare cellular heterogeneity within and across biological conditions using modern multiplexed technologies. PMID:27438699

  7. Robust Inference of Cell-to-Cell Expression Variations from Single- and K-Cell Profiling.

    PubMed

    Narayanan, Manikandan; Martins, Andrew J; Tsang, John S

    2016-07-01

    Quantifying heterogeneity in gene expression among single cells can reveal information inaccessible to cell-population averaged measurements. However, the expression level of many genes in single cells fall below the detection limit of even the most sensitive technologies currently available. One proposed approach to overcome this challenge is to measure random pools of k cells (e.g., 10) to increase sensitivity, followed by computational "deconvolution" of cellular heterogeneity parameters (CHPs), such as the biological variance of single-cell expression levels. Existing approaches infer CHPs using either single-cell or k-cell data alone, and typically within a single population of cells. However, integrating both single- and k-cell data may reap additional benefits, and quantifying differences in CHPs across cell populations or conditions could reveal novel biological information. Here we present a Bayesian approach that can utilize single-cell, k-cell, or both simultaneously to infer CHPs within a single condition or their differences across two conditions. Using simulated as well as experimentally generated single- and k-cell data, we found situations where each data type would offer advantages, but using both together can improve precision and better reconcile CHP information contained in single- and k-cell data. We illustrate the utility of our approach by applying it to jointly generated single- and k-cell data to reveal CHP differences in several key inflammatory genes between resting and inflammatory cytokine-activated human macrophages, delineating differences in the distribution of 'ON' versus 'OFF' cells and in continuous variation of expression level among cells. Our approach thus offers a practical and robust framework to assess and compare cellular heterogeneity within and across biological conditions using modern multiplexed technologies. PMID:27438699

  8. Chemokine receptor expression by inflammatory T cells in EAE

    PubMed Central

    Mony, Jyothi Thyagabhavan; Khorooshi, Reza; Owens, Trevor

    2014-01-01

    Chemokines direct cellular infiltration to tissues, and their receptors and signaling pathways represent targets for therapy in diseases such as multiple sclerosis (MS). The chemokine CCL20 is expressed in choroid plexus, a site of entry of T cells to the central nervous system (CNS). The CCL20 receptor CCR6 has been reported to be selectively expressed by CD4+ T cells that produce the cytokine IL-17 (Th17 cells). Th17 cells and interferon-gamma (IFNγ)-producing Th1 cells are implicated in induction of MS and its animal model experimental autoimmune encephalomyelitis (EAE). We have assessed whether CCR6 identifies specific inflammatory T cell subsets in EAE. Our approach was to induce EAE, and then examine chemokine receptor expression by cytokine-producing T cells sorted from CNS at peak disease. About 7% of CNS-infiltrating CD4+ T cells produced IFNγ in flow cytometric cytokine assays, whereas less than 1% produced IL-17. About 1% of CD4+ T cells produced both cytokines. CCR6 was expressed by Th1, Th1+17 and by Th17 cells, but not by CD8+ T cells. CD8+ T cells expressed CXCR3, which was also expressed by CD4+ T cells, with no correlation to cytokine profile. Messenger RNA for IFNγ, IL-17A, and the Th1 and Th17-associated transcription factors T-bet and RORγt was detected in both CCR6+ and CXCR3+ CD4+ T cells. IFNγ, but not IL-17A mRNA expression was detected in CD8+ T cells in CNS. CCR6 and CD4 were co-localized in spinal cord infiltrates by double immunofluorescence. Consistent with flow cytometry data some but not all CD4+ T cells expressed CCR6 within infiltrates. CD4-negative CCR6+ cells included macrophage/microglial cells. Thus we have for the first time directly studied CD4+ and CD8+ T cells in the CNS of mice with peak EAE, and determined IFNγ and IL17 expression by cells expressing CCR6 and CXCR3. We show that neither CCR6 or CXCR3 align with CD4 T cell subsets, and Th1 or mixed Th1+17 predominate in EAE. PMID:25071447

  9. Geometry of the Gene Expression Space of Individual Cells

    PubMed Central

    Korem, Yael; Szekely, Pablo; Hart, Yuval; Sheftel, Hila; Hausser, Jean; Mayo, Avi; Rothenberg, Michael E.; Kalisky, Tomer; Alon, Uri

    2015-01-01

    There is a revolution in the ability to analyze gene expression of single cells in a tissue. To understand this data we must comprehend how cells are distributed in a high-dimensional gene expression space. One open question is whether cell types form discrete clusters or whether gene expression forms a continuum of states. If such a continuum exists, what is its geometry? Recent theory on evolutionary trade-offs suggests that cells that need to perform multiple tasks are arranged in a polygon or polyhedron (line, triangle, tetrahedron and so on, generally called polytopes) in gene expression space, whose vertices are the expression profiles optimal for each task. Here, we analyze single-cell data from human and mouse tissues profiled using a variety of single-cell technologies. We fit the data to shapes with different numbers of vertices, compute their statistical significance, and infer their tasks. We find cases in which single cells fill out a continuum of expression states within a polyhedron. This occurs in intestinal progenitor cells, which fill out a tetrahedron in gene expression space. The four vertices of this tetrahedron are each enriched with genes for a specific task related to stemness and early differentiation. A polyhedral continuum of states is also found in spleen dendritic cells, known to perform multiple immune tasks: cells fill out a tetrahedron whose vertices correspond to key tasks related to maturation, pathogen sensing and communication with lymphocytes. A mixture of continuum-like distributions and discrete clusters is found in other cell types, including bone marrow and differentiated intestinal crypt cells. This approach can be used to understand the geometry and biological tasks of a wide range of single-cell datasets. The present results suggest that the concept of cell type may be expanded. In addition to discreet clusters in gene-expression space, we suggest a new possibility: a continuum of states within a polyhedron, in which the

  10. Geometry of the Gene Expression Space of Individual Cells.

    PubMed

    Korem, Yael; Szekely, Pablo; Hart, Yuval; Sheftel, Hila; Hausser, Jean; Mayo, Avi; Rothenberg, Michael E; Kalisky, Tomer; Alon, Uri

    2015-07-01

    There is a revolution in the ability to analyze gene expression of single cells in a tissue. To understand this data we must comprehend how cells are distributed in a high-dimensional gene expression space. One open question is whether cell types form discrete clusters or whether gene expression forms a continuum of states. If such a continuum exists, what is its geometry? Recent theory on evolutionary trade-offs suggests that cells that need to perform multiple tasks are arranged in a polygon or polyhedron (line, triangle, tetrahedron and so on, generally called polytopes) in gene expression space, whose vertices are the expression profiles optimal for each task. Here, we analyze single-cell data from human and mouse tissues profiled using a variety of single-cell technologies. We fit the data to shapes with different numbers of vertices, compute their statistical significance, and infer their tasks. We find cases in which single cells fill out a continuum of expression states within a polyhedron. This occurs in intestinal progenitor cells, which fill out a tetrahedron in gene expression space. The four vertices of this tetrahedron are each enriched with genes for a specific task related to stemness and early differentiation. A polyhedral continuum of states is also found in spleen dendritic cells, known to perform multiple immune tasks: cells fill out a tetrahedron whose vertices correspond to key tasks related to maturation, pathogen sensing and communication with lymphocytes. A mixture of continuum-like distributions and discrete clusters is found in other cell types, including bone marrow and differentiated intestinal crypt cells. This approach can be used to understand the geometry and biological tasks of a wide range of single-cell datasets. The present results suggest that the concept of cell type may be expanded. In addition to discreet clusters in gene-expression space, we suggest a new possibility: a continuum of states within a polyhedron, in which the

  11. Mechanism of Testosterone Deficiency in the Transgenic Sickle Cell Mouse

    PubMed Central

    Musicki, Biljana; Zhang, Yuxi; Chen, Haolin; Brown, Terry R.; Zirkin, Barry R.; Burnett, Arthur L.

    2015-01-01

    Testosterone deficiency is associated with sickle cell disease (SCD), but its underlying mechanism is not known. We investigated the possible occurrence and mechanism of testosterone deficiency in a mouse model of human SCD. Transgenic sickle male mice (Sickle) exhibited decreased serum and intratesticular testosterone and increased luteinizing hormone (LH) levels compared with wild type (WT) mice, indicating primary hypogonadism in Sickle mice. LH-, dbcAMP-, and pregnenolone- (but not 22-hydroxycholesterol)- stimulated testosterone production by Leydig cells isolated from the Sickle mouse testis was decreased compared to that of WT mice, implying defective Leydig cell steroidogenesis. There also was reduced protein expression of steroidogenic acute regulatory protein (STAR), but not cholesterol side-chain cleavage enzyme (P450scc), in the Sickle mouse testis. These data suggest that the capacity of P450scc to support testosterone production may be limited by the supply of cholesterol to the mitochondria in Sickle mice. The sickle mouse testis exhibited upregulated NADPH oxidase subunit gp91phox and increased oxidative stress, measured as 4-hydroxy-2-nonenal, and unchanged protein expression of an antioxidant glutathione peroxidase-1. Mice heterozygous for the human sickle globin (Hemi) exhibited intermediate hypogonadal changes between those of WT and Sickle mice. These results demonstrate that testosterone deficiency occurs in Sickle mice, mimicking the human condition. The defects in the Leydig cell steroidogenic pathway in Sickle mice, mainly due to reduced availability of cholesterol for testosterone production, may be related to NADPH oxidase-derived oxidative stress. Our findings suggest that targeting testicular oxidative stress or steroidogenesis mechanisms in SCD offers a potential treatment for improving phenotypic changes associated with testosterone deficiency in this disease. PMID:26023917

  12. Fragments of Target Cells are Internalized into Retroviral Envelope Protein-Expressing Cells during Cell-Cell Fusion by Endocytosis

    PubMed Central

    Izumida, Mai; Kamiyama, Haruka; Suematsu, Takashi; Honda, Eri; Koizumi, Yosuke; Yasui, Kiyoshi; Hayashi, Hideki; Ariyoshi, Koya; Kubo, Yoshinao

    2016-01-01

    Retroviruses enter into host cells by fusion between viral and host cell membranes. Retroviral envelope glycoprotein (Env) induces the membrane fusion, and also mediates cell-cell fusion. There are two types of cell-cell fusions induced by the Env protein. Fusion-from-within is induced by fusion between viral fusogenic Env protein-expressing cells and susceptible cells, and virions induce fusion-from-without by fusion between adjacent cells. Although entry of ecotropic murine leukemia virus (E-MLV) requires host cell endocytosis, the involvement of endocytosis in cell fusion is unclear. By fluorescent microscopic analysis of the fusion-from-within, we found that fragments of target cells are internalized into Env-expressing cells. Treatment of the Env-expressing cells with an endocytosis inhibitor more significantly inhibited the cell fusion than that of the target cells, indicating that endocytosis in Env-expressing cells is required for the cell fusion. The endocytosis inhibitor also attenuated the fusion-from-without. Electron microscopic analysis suggested that the membrane fusion resulting in fusion-from-within initiates in endocytic membrane dents. This study shows that two types of the viral cell fusion both require endocytosis, and provides the cascade of fusion-from-within. PMID:26834711

  13. Characteristics and EGFP expression of porcine mammary gland epithelial cells.

    PubMed

    Zheng, Yue-Mao; He, Xiao-Ying

    2010-12-01

    The aims of this study were to establish a porcine mammary gland epithelial (PMGE) cell line, and to determine if these PMGE cells could be maintained long-term in culture by continuous subculturing following transfection with a reporter gene, enhanced green fluorescence protein (EGFP). Primary culture of PMGE cells was achieved by outgrowth of migrating cells from the fragments of the mammary gland tissue of a lactating pig. The passage sixteen PMGE cells were transfected with EGFP gene using lipofection. The expression of Cell keratins of epithelial cells in PMGE cells was tested by immunofluorescence. Βeta-Casein gene mRNA was tested for PMGE cells by RT-PCR. The results showed that PMGE cells could form dome-like structure which looked like nipple, and the cells contained different cell types. The expression of Cell keratins demonstrated the property of epithelial cells, and the PMGE cells could express transcript encoding a Βeta-Casein protein. EGFP gene was successfully transferred into the PMGE cells, and the transfected cells could be maintained long-term in culture by continuous subculturing. In conclusion, we have established a EGFP gene transfected porcine mammary gland epithelial (ET-PMGE) cell line. PMID:20400167

  14. HeLa Based Cell Free Expression Systems for Expression of Plasmodium Rhoptry Proteins.

    PubMed

    Yadavalli, Raghavendra; Sam-Yellowe, Tobili

    2015-01-01

    Malaria causes significant global morbidity and mortality. No routine vaccine is currently available. One of the major reasons for lack of a vaccine is the challenge of identifying suitable vaccine candidates. Malarial proteins expressed using prokaryotic and eukaryotic cell based expression systems are poorly glycosylated, generally insoluble and undergo improper folding leading to reduced immunogenicity. The wheat germ, rabbit reticulocyte lysate and Escherichia coli lysate cell free expression systems are currently used for expression of malarial proteins. However, the length of expression time and improper glycosylation of proteins still remains a challenge. We demonstrate expression of Plasmodium proteins in vitro using HeLa based cell free expression systems, termed "in vitro human cell free expression systems". The 2 HeLa based cell free expression systems transcribe mRNA in 75 min and 3 µl of transcribed mRNA is sufficient to translate proteins in 90 min. The 1-step expression system is a transcription and translation coupled expression system; the transcription and co-translation occurs in 3 hr. The process can also be extended for 6 hr by providing additional energy. In the 2-step expression system, mRNA is first transcribed and then added to the translation mix for protein expression. We describe how to express malaria proteins; a hydrophobic PF3D7_0114100 Maurer's Cleft - 2 transmembrane (PfMC-2TM) protein, a hydrophilic PF3D7_0925900 protein and an armadillo repeats containing protein PF3D7_1361800, using the HeLa based cell free expression system. The proteins are expressed in micro volumes employing 2-step and 1-step expression strategies. An affinity purification method to purify 25 µl of proteins expressed using the in vitro human cell free expression system is also described. Protein yield is determined by Bradford's assay and the expressed and purified proteins can be confirmed by western blotting analysis. Expressed recombinant proteins can be

  15. Etoposide sensitizes neuroblastoma cells expressing caspase 8 to TRAIL.

    PubMed

    Kim, Hye Ryung; Lee, Myoung Woo; Kim, Dae Seong; Jo, Ha Yeong; Lee, Soo Hyun; Chueh, Hee Won; Jung, Hye Lim; Yoo, Keon Hee; Sung, Ki Woong; Koo, Hong Hoe

    2012-01-01

    TRAIL [TNF (tumour necrosis factor)-related apoptosis-inducing ligand] is a promising agent for clinical use since it kills a wide range of tumour cells without affecting normal cells. We provide evidence that pretreatment with etoposide significantly enhanced TRAIL-mediated apoptosis via up-regulation of DR5 (death receptor 5 or TRAIL-R2) expression in the caspase 8 expressing neuroblastoma cell line, SK-N-MC. In addition, sequential treatment with etoposide and TRAIL increased caspases 8, 9 and 3 activation, Mcl-1 cleavage and Bid truncation, which suggests that the ability of etoposide and TRAIL to induce apoptosis is mediated through activation of an intrinsic signalling pathway. Although TRAIL-R2 expression increased in IMR-32 cells in response to etoposide treatment, cell death was not increased by concurrent treatment with TRAIL compared with etoposide alone, because the cells lacked caspase 8 expression. Restoration of caspase 8 expression by exposure to IFNγ (interferon γ) sensitizes IMR-32 cells to TRAIL. Moreover, pretreatment with etoposide increased TRAIL-induced apoptosis in caspase 8 restored IMR-32 cells through activation of a caspase cascade that included caspases 8, 9 and 3. These results indicate that the etoposide-mediated sensitization of neuroblastoma cells to TRAIL is associated with an increase in TRAIL-R2 expression and requires caspase 8 expression. These observations support the potential use of a combination of etoposide and TRAIL in future clinical trials. PMID:23124518

  16. Differential expression and function of CD27 in chronic lymphocytic leukemia cells expressing ZAP-70.

    PubMed

    Lafarge, Sandrine T; Hou, Sen; Pauls, Samantha D; Johnston, James B; Gibson, Spencer B; Marshall, Aaron J

    2015-07-01

    Chronic lymphocytic leukemia is a malignancy driven by abberant B cell signaling and survival. Leukemic B cells accumulate in the peripheral blood and the lymphoid organs where contact with stromal cells and T cells provide critical survival signals. Clinical severity of CLL is associated with several prognostic markers including expression of the kinase ZAP-70. ZAP-70 expression enhances signaling via the B cell antigen receptor and is associated with increased cell adhesion and migration capacity. Here we report that ZAP-70-positive CLL patients display significantly higher expression of the TNF superfamily receptor and memory marker CD27 than do ZAP-70 negative patients. CD27 expression by CLL was acutely elevated upon BCR cross-linking, or upon ectopic expression of ZAP-70. CD27 expression correlated with functional capacity to adhere to stromal cells and antibody blockade of CD27 impaired CLL binding to stroma. These results provide the first evidence for differential expression of CD27 among CLL prognostic groups, suggest a role for ZAP-70 dependent signaling in CD27 induction and implicate CD27 in cell-cell interactions with the lymphoid tissue microenvironment. PMID:26002513

  17. Calreticulin: Roles in Cell-Surface Protein Expression

    PubMed Central

    Jiang, Yue; Dey, Sandeepa; Matsunami, Hiroaki

    2014-01-01

    In order to perform their designated functions, proteins require precise subcellular localizations. For cell-surface proteins, such as receptors and channels, they are able to transduce signals only when properly targeted to the cell membrane. Calreticulin is a multi-functional chaperone protein involved in protein folding, maturation, and trafficking. However, evidence has been accumulating that calreticulin can also negatively regulate the surface expression of certain receptors and channels. In these instances, depletion of calreticulin enhances cell-surface expression and function. In this review, we discuss the role of calreticulin with a focus on its negative effects on the expression of cell-surface proteins. PMID:25230046

  18. CD39 Expression Identifies Terminally Exhausted CD8+ T Cells

    PubMed Central

    Adland, Emily; Yates, Kathleen; Pauken, Kristen E.; Cosgrove, Cormac; Ledderose, Carola; Junger, Wolfgang G.; Robson, Simon C.; Wherry, E. John; Alter, Galit; Goulder, Philip J. R.; Klenerman, Paul; Sharpe, Arlene H.; Lauer, Georg M.; Haining, W. Nicholas

    2015-01-01

    Exhausted T cells express multiple co-inhibitory molecules that impair their function and limit immunity to chronic viral infection. Defining novel markers of exhaustion is important both for identifying and potentially reversing T cell exhaustion. Herein, we show that the ectonucleotidse CD39 is a marker of exhausted CD8+ T cells. CD8+ T cells specific for HCV or HIV express high levels of CD39, but those specific for EBV and CMV do not. CD39 expressed by CD8+ T cells in chronic infection is enzymatically active, co-expressed with PD-1, marks cells with a transcriptional signature of T cell exhaustion and correlates with viral load in HIV and HCV. In the mouse model of chronic Lymphocytic Choriomeningitis Virus infection, virus-specific CD8+ T cells contain a population of CD39high CD8+ T cells that is absent in functional memory cells elicited by acute infection. This CD39high CD8+ T cell population is enriched for cells with the phenotypic and functional profile of terminal exhaustion. These findings provide a new marker of T cell exhaustion, and implicate the purinergic pathway in the regulation of T cell exhaustion. PMID:26485519

  19. Determining Physical Mechanisms of Gene Expression Regulation from Single Cell Gene Expression Data.

    PubMed

    Ezer, Daphne; Moignard, Victoria; Göttgens, Berthold; Adryan, Boris

    2016-08-01

    Many genes are expressed in bursts, which can contribute to cell-to-cell heterogeneity. It is now possible to measure this heterogeneity with high throughput single cell gene expression assays (single cell qPCR and RNA-seq). These experimental approaches generate gene expression distributions which can be used to estimate the kinetic parameters of gene expression bursting, namely the rate that genes turn on, the rate that genes turn off, and the rate of transcription. We construct a complete pipeline for the analysis of single cell qPCR data that uses the mathematics behind bursty expression to develop more accurate and robust algorithms for analyzing the origin of heterogeneity in experimental samples, specifically an algorithm for clustering cells by their bursting behavior (Simulated Annealing for Bursty Expression Clustering, SABEC) and a statistical tool for comparing the kinetic parameters of bursty expression across populations of cells (Estimation of Parameter changes in Kinetics, EPiK). We applied these methods to hematopoiesis, including a new single cell dataset in which transcription factors (TFs) involved in the earliest branchpoint of blood differentiation were individually up- and down-regulated. We could identify two unique sub-populations within a seemingly homogenous group of hematopoietic stem cells. In addition, we could predict regulatory mechanisms controlling the expression levels of eighteen key hematopoietic transcription factors throughout differentiation. Detailed information about gene regulatory mechanisms can therefore be obtained simply from high throughput single cell gene expression data, which should be widely applicable given the rapid expansion of single cell genomics. PMID:27551778

  20. Determining Physical Mechanisms of Gene Expression Regulation from Single Cell Gene Expression Data

    PubMed Central

    Moignard, Victoria; Göttgens, Berthold; Adryan, Boris

    2016-01-01

    Many genes are expressed in bursts, which can contribute to cell-to-cell heterogeneity. It is now possible to measure this heterogeneity with high throughput single cell gene expression assays (single cell qPCR and RNA-seq). These experimental approaches generate gene expression distributions which can be used to estimate the kinetic parameters of gene expression bursting, namely the rate that genes turn on, the rate that genes turn off, and the rate of transcription. We construct a complete pipeline for the analysis of single cell qPCR data that uses the mathematics behind bursty expression to develop more accurate and robust algorithms for analyzing the origin of heterogeneity in experimental samples, specifically an algorithm for clustering cells by their bursting behavior (Simulated Annealing for Bursty Expression Clustering, SABEC) and a statistical tool for comparing the kinetic parameters of bursty expression across populations of cells (Estimation of Parameter changes in Kinetics, EPiK). We applied these methods to hematopoiesis, including a new single cell dataset in which transcription factors (TFs) involved in the earliest branchpoint of blood differentiation were individually up- and down-regulated. We could identify two unique sub-populations within a seemingly homogenous group of hematopoietic stem cells. In addition, we could predict regulatory mechanisms controlling the expression levels of eighteen key hematopoietic transcription factors throughout differentiation. Detailed information about gene regulatory mechanisms can therefore be obtained simply from high throughput single cell gene expression data, which should be widely applicable given the rapid expansion of single cell genomics. PMID:27551778

  1. Stochasticity in gene expression in a cell-sized compartment.

    PubMed

    Nishimura, Kazuya; Tsuru, Saburo; Suzuki, Hiroaki; Yomo, Tetsuya

    2015-05-15

    The gene expression in a clonal cell population fluctuates significantly, and its relevance to various cellular functions is under intensive debate. A fundamental question is whether the fluctuation is a consequence of the complexity and redundancy in living cells or an inevitable attribute of the minute microreactor nature of cells. To answer this question, we constructed an artificial cell, which consists of only necessary components for the gene expression (in vitro transcription and translation system) and its boundary as a microreactor (cell-sized lipid vesicle), and investigated the gene expression noise. The variation in the expression of two fluorescent proteins was decomposed into the components that were correlated and uncorrelated between the two proteins using a method similar to the one used by Elowitz and co-workers to analyze the expression noise in E. coli. The observed fluctuation was compared with a theoretical model that expresses the amplitude of noise as a function of the average number of intermediate molecules and products. With the assumption that the transcripts are partly active, the theoretical model was able to well describe the noise in the artificial system. Furthermore, the same measurement for E. coli cells harboring an identical plasmid revealed that the E. coli exhibited a similar level of expression noise. Our results demonstrated that the level of fluctuation found in bacterial cells is mostly an intrinsic property that arises even in a primitive form of the cell. PMID:25280237

  2. CARD14 Expression in Dermal Endothelial Cells in Psoriasis

    PubMed Central

    Harden, Jamie L.; Lewis, Steven M.; Pierson, Katherine C.; Suárez-Fariñas, Mayte; Lentini, Tim; Ortenzio, Francesca S.; Zaba, Lisa C.; Goldbach-Mansky, Raphaela; Bowcock, Anne M.; Lowes, Michelle A.

    2014-01-01

    Mutations in the caspase recruitment domain, family member 14 (CARD14) gene have recently been described in psoriasis patients, and explain the psoriasis susceptibility locus 2 (PSORS2). CARD14 is a scaffolding protein that regulates NF-κB activation, and psoriasis-associated CARD14 mutations lead to enhanced NF-κB signaling. CARD14 is expressed mainly in epidermal keratinocytes, but also in unidentified dermal cells. In this manuscript, the identity of the dermal cell types expressing CARD14, as well the potential functional consequence of overactive CARD14 in these dermal cell types, was determined. Using two-color immunofluorescence, dermal CARD14 did not co-localize with T-cells, dendritic cells, or macrophages. However, dermal CARD14 did highly co-localize with CD31+ endothelial cells (ECs). CARD14 was also expressed non-dermal endothelial cells, such as aortic endothelial cells, which may indicate a role of CARD14+ECs in the systemic inflammation and cardiovascular comorbidities associated with psoriasis. Additionally, phosphorylated NF-κB was found in psoriatic CARD14+ CD31+ ECs, demonstrating this pathway is active in dermal ECs in psoriasis. Transfection of dermal ECs with psoriasis-associated CARD14 mutations resulted in increased expression of several chemokines, including CXCL10, IL-8, and CCL2. These results provide preliminary evidence that CARD14 expression in ECs may contribute to psoriasis through increased expression of chemokines and facilitating recruitment of immune cells into skin. PMID:25369198

  3. CARD14 expression in dermal endothelial cells in psoriasis.

    PubMed

    Harden, Jamie L; Lewis, Steven M; Pierson, Katherine C; Suárez-Fariñas, Mayte; Lentini, Tim; Ortenzio, Francesca S; Zaba, Lisa C; Goldbach-Mansky, Raphaela; Bowcock, Anne M; Lowes, Michelle A

    2014-01-01

    Mutations in the caspase recruitment domain, family member 14 (CARD14) gene have recently been described in psoriasis patients, and explain the psoriasis susceptibility locus 2 (PSORS2). CARD14 is a scaffolding protein that regulates NF-κB activation, and psoriasis-associated CARD14 mutations lead to enhanced NF-κB signaling. CARD14 is expressed mainly in epidermal keratinocytes, but also in unidentified dermal cells. In this manuscript, the identity of the dermal cell types expressing CARD14, as well the potential functional consequence of overactive CARD14 in these dermal cell types, was determined. Using two-color immunofluorescence, dermal CARD14 did not co-localize with T-cells, dendritic cells, or macrophages. However, dermal CARD14 did highly co-localize with CD31(+) endothelial cells (ECs). CARD14 was also expressed non-dermal endothelial cells, such as aortic endothelial cells, which may indicate a role of CARD14(+)ECs in the systemic inflammation and cardiovascular comorbidities associated with psoriasis. Additionally, phosphorylated NF-κB was found in psoriatic CARD14(+) CD31(+) ECs, demonstrating this pathway is active in dermal ECs in psoriasis. Transfection of dermal ECs with psoriasis-associated CARD14 mutations resulted in increased expression of several chemokines, including CXCL10, IL-8, and CCL2. These results provide preliminary evidence that CARD14 expression in ECs may contribute to psoriasis through increased expression of chemokines and facilitating recruitment of immune cells into skin. PMID:25369198

  4. CD40 expression in Wehi-164 cell line

    PubMed Central

    Ebadi, Padideh; Pourfathollah, Ali Akbar; Soheili, Zahra Soheila; Moazzeni, Seyed Mohammad

    2010-01-01

    CD40-CD154 interaction is an important process for cellular and humoral immunity regulation and can be effective in the body’s defense against tumors. In the present study, we evaluated the expression of CD40 in Wehi-164 cell line. CD40 expressions on the cell surface and in the cytoplasm were assessed by flow cytometry and intracellular staining assay, respectively. Also, the mRNA expression was identified by real time-PCR. The obtained results showed the high mRNA and cytoplasmic protein expression of CD40 but no surface expression. These results suggest that the Wehi-164 cell line down regulates expression of CD40 on the surface for evasion of immune system. PMID:20496113

  5. Molecular Background of Estrogen Receptor Gene Expression in Endometriotic Cells.

    PubMed

    Izawa, Masao; Taniguchi, Fuminori; Harada, Tasuku

    2016-07-01

    The molecular background of estrogen receptor (ER) expression is important to understand the pathophysiology of the high estrogen environment in endometriosis. However, the molecular details have not been fully understood. The objective of this study is to evaluate the molecular background of ERα and ERβ messenger RNA (mRNA) expression in endometriotic cells. The following summarizes our observations: (1) ERα mRNA expression in endometriotic cells was estimated to be approximately one-tenth of that in endometrial cells. (2) Three mRNAs, which include 3 different 5'-untranslated exons tagged to an open reading frame of wild-type ERα, were detected. (3) Expression of ERβ mRNA depends mostly on 0N promoter and includes 2 open reading frames: one for a wild-type ERβ1 and another for a splice variant ERβ2. (4) Expression of ERβ1 mRNA was approximately 40-fold higher than that in endometrial cells. (5) Expression of ERβ2 mRNA was almost at a comparable level of the ERβ1. 9 (6) ERα and ERβ mRNAs are equivalently expressed in endometriotic cells. These observations show the molecular background of ER mRNA expression in endometriotic cells and provide a clue to further understanding the estrogen-dependent pathophysiology leading to clinical application in endometriosis. PMID:26704524

  6. Cyclin Dl expression in B-cell non Hodgkin lymphoma.

    PubMed

    Aref, Salah; Mossad, Y; El-Khodary, T; Awad, M; El-Shahat, E

    2006-10-01

    Disorders of the cell cycle regulatory machinery play a key role in the pathogenesis of cancer. Over-expression of cyclin D1 protein has been reported in several solid tumors and certain lymphoid malignancies, but little is known about the effect of its expression on clinical behavior and outcome in B-cell Non-Hodgkin lymphoma (NHL). In this study, we investigated the expression of cyclin Dl in group of patients with NHL and correlated the results with the clinical and laboratory data. The degree of expression of cyclin Dl protein was evaluated by flow cytometry in a group of NHL patients (n = 46) and in normal control group (n = 10). Cyclin Dl over expression was detected in 10 out of 46 (21.7%) patients; they were 5/5-mantle cell lymphoma (MCL) (100%) and 5/28 large B-cell lymphoma (17.8%). All other NHL subtypes showed normal cyclin D1 expression. The clinical signs (hepatomegaly, splenomegaly and B-symptoms, clinical staging) and laboratory data (hemoglobin, white cell count (WBCs), platelet count, and bone marrow infiltration) were not significantly different between NHL subgroup with cyclin Dl over expression and that with normal cyclin Dl expression. Serum lactic dehydrogenase (LDH) levels and lymphadenopathy were significantly higher in NHL group with cyclin D1 over expression as compared to those without. Also, cyclin D1 over expression is associated with poor outcome of NHL patients. Cyclin Dl over expression was evident among all cases of MCL and few cases of large B-cell lymphoma. Cyclin Dl over expression might be used as adjuvant tool for diagnosis of MCL; has role in NHL biology and is bad prognostic index in NHL. PMID:17607588

  7. Expression of MIF and CD74 in leukemic cell lines: correlation to DR expression destiny.

    PubMed

    Georgouli, Mirella; Papadimitriou, Lina; Glymenaki, Maria; Patsaki, Valia; Athanassakis, Irene

    2016-06-01

    Invariant chain (Ii) or CD74 is a non-polymorphic glycoprotein, which apart from its role as a chaperone dedicated to MHCII molecules, is known to be a high-affinity receptor for macrophage migration inhibitory factor (MIF). The present study aimed to define the roles of CD74 and MIF in the immune surveillance escape process. Towards this direction, the cell lines HL-60, Raji, K562 and primary pre-B leukemic cells were examined for expression and secretion of MIF. Flow cytometry analysis detected high levels of MIF and intracellular/membrane CD74 expression in all leukemic cells tested, while MIF secretion was shown to be inversely proportional to intracellular HLA-DR (DR) expression. In the MHCII-negative cells, IFN-γ increased MIF expression and induced its secretion in HL-60 and K562 cells, respectively. In K562 cells, CD74 (Iip33Iip35) was shown to co-precipitate with HLA-DOβ (DOβ), inhibiting thus MIF or DR binding. Induced expression of DOα in K562 (DOα-DOβ+) cells in different transfection combinations decreased MIF expression and secretion, while increasing surface DR expression. Thus, MIF could indeed be part of the antigen presentation process. PMID:26866879

  8. Biased Allelic Expression in Human Primary Fibroblast Single Cells

    PubMed Central

    Borel, Christelle; Ferreira, Pedro G.; Santoni, Federico; Delaneau, Olivier; Fort, Alexandre; Popadin, Konstantin Y.; Garieri, Marco; Falconnet, Emilie; Ribaux, Pascale; Guipponi, Michel; Padioleau, Ismael; Carninci, Piero; Dermitzakis, Emmanouil T.; Antonarakis, Stylianos E.

    2015-01-01

    The study of gene expression in mammalian single cells via genomic technologies now provides the possibility to investigate the patterns of allelic gene expression. We used single-cell RNA sequencing to detect the allele-specific mRNA level in 203 single human primary fibroblasts over 133,633 unique heterozygous single-nucleotide variants (hetSNVs). We observed that at the snapshot of analyses, each cell contained mostly transcripts from one allele from the majority of genes; indeed, 76.4% of the hetSNVs displayed stochastic monoallelic expression in single cells. Remarkably, adjacent hetSNVs exhibited a haplotype-consistent allelic ratio; in contrast, distant sites located in two different genes were independent of the haplotype structure. Moreover, the allele-specific expression in single cells correlated with the abundance of the cellular transcript. We observed that genes expressing both alleles in the majority of the single cells at a given time point were rare and enriched with highly expressed genes. The relative abundance of each allele in a cell was controlled by some regulatory mechanisms given that we observed related single-cell allelic profiles according to genes. Overall, these results have direct implications in cellular phenotypic variability. PMID:25557783

  9. Optimizing transient recombinant protein expression in mammalian cells.

    PubMed

    Hopkins, Ralph F; Wall, Vanessa E; Esposito, Dominic

    2012-01-01

    Transient gene expression (TGE) in mammalian cells has become a routine process for expressing recombinant proteins in cell lines such as human embryonic kidney 293 and Chinese hamster ovary cells. The rapidly increasing need for recombinant proteins requires further improvements in TGE technology. While a great deal of focus has been directed toward optimizing the secretion of antibodies and other naturally secreted targets, much less work has been done on ways to improve cytoplasmic expression in mammalian cells. The benefits to protein production in mammalian cells, particularly for eukaryotic proteins, should be very significant - glycosylation and other posttranslational modifications will likely be native or near-native, solubility and protein folding would likely improve overexpression in heterologous hosts, and expression of proteins in their proper intracellular compartments is much more likely to occur. Improvements in this area have been slow, however, due to limited development of the cell culture processes needed for low-cost, higher-throughput expression in mammalian cells, and the relatively low diversity of DNA vectors for protein production in these systems. Here, we describe how the use of recombinational cloning, coupled with improvements in transfection protocols which increase speed and lower cost, can be combined to make mammalian cells much more amenable for routine recombinant protein expression. PMID:21987258

  10. Evidence of tricellulin expression by immune cells, particularly microglia.

    PubMed

    Mariano, Cibelle; Silva, Sandra Leitão; Pereira, Pedro; Fernandes, Adelaide; Brites, Dora; Brito, Maria A

    2011-06-17

    Tight junctions (TJs) are elaborate structures located on the apical region of epithelial cells that limit paracellular permeability. Tricellulin is a recently discovered TJ protein, which is concentrated at the structurally specialized tricellular TJs but also present at bicellular contacts between epithelial cells, namely in the stomach. Interestingly, several TJ proteins have been found in other than epithelial cells, as astrocytes, and tricellulin mRNA expression was reported in mature dendritic cells. These findings prompted us to look for tricellulin expression in both epithelial and immune cells in the stomach, as well as in microglia, the brain resident immunocompetent cells. Immunohistochemical analysis of human stomach tissue sections revealed peroxidase staining at three-corner contact sites, as well as at the contact between two adjacent epithelial cells, thus evidencing the expression of tricellulin not only at tricellullar but at bicellular junctions as well. Such analysis, further revealed tricellulin immunostaining in cells of the monocyte/macrophage lineage, scattered throughout the lamina propria. Cultured rat microglia exhibited a notorious tricellulin staining, consistent with an extensive expression of the protein along the cell, which was not absolutely coincident with the lysosomal marker CD68. Detection of mRNA expression by real-time PCR provided supportive evidence for the expression of the TJ protein in microglia. These data demonstrate for the first time that microglia express a TJ protein. Moreover, the expression of tricellulin both in microglia and in the stomach immune cells point to a possible role of this new TJ protein in the immune system. PMID:21624353

  11. Regulated expression of erythropoietin by two human hepatoma cell lines

    SciTech Connect

    Goldberg, M.A.; Glass, G.A.; Cunningham, J.M.; Bunn, H.F.

    1987-11-01

    The development of a cell culture system that produces erythropoietin (Epo) in a regulated manner has been the focus of much effort. The authors have screened multiple renal and hepatic cell lines for either constitutive or regulated expression of Epo. Only the human hepatoma cell lines, Hep3B and HepG2, made significant amounts of Epo as measured both by radioimmunoassay and in vitro bioassay (as much as 330 milliunits per 10/sup 6/ cells in 24 hr). The constitutive production of Epo increased dramatically as a function of cell density in both cell lines. At cell densities < 3.3 x 10/sup 5/ cells per cm/sup 2/, there was little constitutive release of Epo in the medium. With Hep3B cells grown at low cell densities, a mean 18-fold increase in Epo expression was seen in response to hypoxia and a 6-fold increase was observed in response to incubation in medium containing 50 ..mu..M cobalt(II) chloride. At similar low cell densities, Epo production in HepG2 cells could be enhanced an average of about 3-fold by stimulation with either hypoxia or cobalt(II) chloride. Upon such stimulation, both cell lines demonstrated markedly elevated levels of Epo mRNA. Hence, both Hep3B and HepG2 cell lines provide an excellent in vitro system in which to study the physiological regulation of Epo expression.

  12. Expression of Secretogranin III in Chicken Endocrine Cells

    PubMed Central

    Morikawa, Satomi; Shinmura, Naoki; Moki, Hiroaki; Yasui, Tadashi; Tsukise, Azuma; Torii, Seiji; Watanabe, Tsuyoshi; Maeda, Yoshinori; Hosaka, Masahiro

    2015-01-01

    The expression of secretogranin III (SgIII) in chicken endocrine cells has not been investigated. There is limited data available for the immunohistochemical localization of SgIII in the brain, pituitary, and pancreatic islets of humans and rodents. In the present study, we used immunoblotting to reveal the similarities between the expression patterns of SgIII in the common endocrine glands of chickens and rats. The protein–protein interactions between SgIII and chromogranin A (CgA) mediate the sorting of CgA/prohormone core aggregates to the secretory granule membrane. We examined these interactions using co-immunoprecipitation in chicken endocrine tissues. Using immunohistochemistry, we also examined the expression of SgIII in a wide range of chicken endocrine glands and gastrointestinal endocrine cells (GECs). SgIII was expressed in the pituitary, pineal, adrenal (medullary parts), parathyroid, and ultimobranchial glands, but not in the thyroid gland. It was also expressed in GECs of the stomach (proventriculus and gizzard), small and large intestines, and pancreatic islet cells. These SgIII-expressing cells co-expressed serotonin, somatostatin, gastric inhibitory polypeptide, glucagon-like peptide-1, glucagon, or insulin. These results suggest that SgIII is expressed in the endocrine cells that secrete peptide hormones, which mature via the intragranular enzymatic processing of prohormones and physiologically active amines in chickens. PMID:25673289

  13. Regulation of global gene expression and cell proliferation by APP.

    PubMed

    Wu, Yili; Zhang, Si; Xu, Qin; Zou, Haiyan; Zhou, Weihui; Cai, Fang; Li, Tingyu; Song, Weihong

    2016-01-01

    Down syndrome (DS), caused by trisomy of chromosome 21, is one of the most common genetic disorders. Patients with DS display growth retardation and inevitably develop characteristic Alzheimer's disease (AD) neuropathology, including neurofibrillary tangles and neuritic plaques. The expression of amyloid precursor protein (APP) is increased in both DS and AD patients. To reveal the function of APP and elucidate the pathogenic role of increased APP expression in DS and AD, we performed gene expression profiling using microarray method in human cells overexpressing APP. A set of genes are significantly altered, which are involved in cell cycle, cell proliferation and p53 signaling. We found that overexpression of APP inhibits cell proliferation. Furthermore, we confirmed that the downregulation of two validated genes, PSMA5 and PSMB7, inhibits cell proliferation, suggesting that the downregulation of PSMA5 and PSMB7 is involved in APP-induced cell proliferation impairment. Taken together, this study suggests that APP regulates global gene expression and increased APP expression inhibits cell proliferation. Our study provides a novel insight that APP overexpression may contribute to the growth impairment in DS patients and promote AD pathogenesis by inhibiting cell proliferation including neural stem cell proliferation and neurogenesis. PMID:26936520

  14. Regulation of global gene expression and cell proliferation by APP

    PubMed Central

    Wu, Yili; Zhang, Si; Xu, Qin; Zou, Haiyan; Zhou, Weihui; Cai, Fang; Li, Tingyu; Song, Weihong

    2016-01-01

    Down syndrome (DS), caused by trisomy of chromosome 21, is one of the most common genetic disorders. Patients with DS display growth retardation and inevitably develop characteristic Alzheimer’s disease (AD) neuropathology, including neurofibrillary tangles and neuritic plaques. The expression of amyloid precursor protein (APP) is increased in both DS and AD patients. To reveal the function of APP and elucidate the pathogenic role of increased APP expression in DS and AD, we performed gene expression profiling using microarray method in human cells overexpressing APP. A set of genes are significantly altered, which are involved in cell cycle, cell proliferation and p53 signaling. We found that overexpression of APP inhibits cell proliferation. Furthermore, we confirmed that the downregulation of two validated genes, PSMA5 and PSMB7, inhibits cell proliferation, suggesting that the downregulation of PSMA5 and PSMB7 is involved in APP-induced cell proliferation impairment. Taken together, this study suggests that APP regulates global gene expression and increased APP expression inhibits cell proliferation. Our study provides a novel insight that APP overexpression may contribute to the growth impairment in DS patients and promote AD pathogenesis by inhibiting cell proliferation including neural stem cell proliferation and neurogenesis. PMID:26936520

  15. Expression Profiling of Developing Zebrafish Retinal Cells.

    PubMed

    Mullally, Madelyn; Albrecht, Caitlin; Horton, Mary; Laboissonniere, Lauren A; Goetz, Jillian J; Chowdhury, Rebecca; Manning, Alicia; Wester, Andrea K; Bose, Quinton; Trimarchi, Jeffrey M

    2016-08-01

    During retinal development, a variety of different types of neurons are produced. Understanding how each of these types of retinal nerve cells is generated is important from a developmental biology perspective. It is equally important if one is interested in how to regenerate cells after an injury or a disease. To gain more insight into how retinal neurons develop in the zebrafish, we performed single-cell mRNA profiling and in situ hybridizations (ISHs) on retinal sections and whole-mount zebrafish. Through the series of ISHs, designed and performed solely by undergraduate students in the laboratory, we were able to retrospectively identify our single-cell mRNA profiles as most likely coming from developing amacrine cells. Further analysis of these profiles will reveal genes that can be mutated using genome editing techniques. Together these studies increase our knowledge of the genes driving development of different cell types in the zebrafish retina. PMID:26982811

  16. ALDH isozymes downregulation affects cell growth, cell motility and gene expression in lung cancer cells

    PubMed Central

    Moreb, Jan S; Baker, Henry V; Chang, Lung-Ji; Amaya, Maria; Lopez, M Cecilia; Ostmark, Blanca; Chou, Wayne

    2008-01-01

    Background Aldehyde dehydrogenase isozymes ALDH1A1 and ALDH3A1 are highly expressed in non small cell lung cancer. Neither the mechanisms nor the biologic significance for such over expression have been studied. Methods We have employed oligonucleotide microarrays to analyze changes in gene profiles in A549 lung cancer cell line in which ALDH activity was reduced by up to 95% using lentiviral mediated expression of siRNA against both isozymes (Lenti 1+3). Stringent analysis methods were used to identify gene expression patterns that are specific to the knock down of ALDH activity and significantly different in comparison to wild type A549 cells (WT) or cells similarly transduced with green fluorescent protein (GFP) siRNA. Results We confirmed significant and specific down regulation of ALDH1A1 and ALDH3A1 in Lenti 1+3 cells and in comparison to 12 other ALDH genes detected. The results of the microarray analysis were validated by real time RT-PCR on RNA obtained from Lenti 1+3 or WT cells treated with ALDH activity inhibitors. Detailed functional analysis was performed on 101 genes that were significantly different (P < 0.001) and their expression changed by ≥ 2 folds in the Lenti 1+3 group versus the control groups. There were 75 down regulated and 26 up regulated genes. Protein binding, organ development, signal transduction, transcription, lipid metabolism, and cell migration and adhesion were among the most affected pathways. Conclusion These molecular effects of the ALDH knock-down are associated with in vitro functional changes in the proliferation and motility of these cells and demonstrate the significance of ALDH enzymes in cell homeostasis with a potentially significant impact on the treatment of lung cancer. PMID:19025616

  17. Engineering Cells to Improve Protein Expression

    PubMed Central

    Xiao, Su; Shiloach, Joseph; Betenbaugh, Michael J.

    2014-01-01

    Cellular engineering of bacteria, fungi, insect cells and mammalian cells is a promising methodology to improve recombinant protein production for structural, biochemical, and commercial applications. Increased understanding of the host organism biology has suggested engineering strategies targeting bottlenecks in transcription, translation, protein processing and secretory pathways, as well as cell growth and survival. A combination of metabolic engineering and synthetic biology has been used to improve the properties of cells for protein production, which has resulted in enhanced yields of multiple protein classes. PMID:24704806

  18. Over-expression of secreted proteins from mammalian cell lines

    PubMed Central

    Dalton, Annamarie C; Barton, William A

    2014-01-01

    Secreted mammalian proteins require the development of robust protein over-expression systems for crystallographic and biophysical studies of protein function. Due to complex disulfide bonds and distinct glycosylation patterns preventing folding and expression in prokaryotic expression hosts, many secreted proteins necessitate production in more complex eukaryotic expression systems. Here, we elaborate on the methods used to obtain high yields of purified secreted proteins from transiently or stably transfected mammalian cell lines. Among the issues discussed are the selection of appropriate expression vectors, choice of signal sequences for protein secretion, availability of fusion tags for enhancing protein stability and purification, choice of cell line, and the large-scale growth of cells in a variety of formats. PMID:24510886

  19. Analysis of variation of amplitudes in cell cycle gene expression

    PubMed Central

    Liu, Delong; Gaido, Kevin W; Wolfinger, Russ

    2005-01-01

    Background Variation in gene expression among cells in a population is often considered as noise produced from gene transcription and post-transcription processes and experimental artifacts. Most studies on noise in gene expression have emphasized a few well-characterized genes and proteins. We investigated whether different cell-arresting methods have impacts on the maximum expression levels (amplitudes) of a cell cycle related gene. Results By introducing random noise, modeled by a von Mises distribution, to the phase angle in a sinusoidal model in a cell population, we derived a relationship between amplitude and the distribution of noise in maximum transcription time (phase). We applied our analysis to Whitfield's HeLa cell cycle data. Our analysis suggests that among 47 cell cycle related genes common to the 2nd experiment (thymidine-thymidine method) and the 4th experiment (thymidine-nocodazole method): (i) the amplitudes of CDC6 and PCNA, which are expressed during G1/S phase, are smaller in the 2nd experiment than in the 4th, while the amplitude of CDC20, which is expressed during G2/M phase, is smaller in the 4th experiment; and (ii) the two cell-arresting methods had little impact on the amplitudes of the other 43 genes in the 2nd and 4th experiments. Conclusion Our analysis suggests that procedures that arrest cells in different stages of the cell cycle differentially affect expression of some cell cycle related genes once the cells are released from arrest. The impact of the cell-arresting method on expression of a cell cycle related gene can be quantitatively estimated from the ratio of two estimated amplitudes in two experiments. The ratio can be used to gauge the variation in the phase/peak expression time distribution involved in stochastic transcription and post-transcriptional processes for the gene. Further investigations are needed using normal, unperturbed and synchronized HeLa cells as a reference to compare how many cell cycle related genes

  20. Langerhans' cell expression of the selectin ligand, sialyl Lewis x.

    PubMed Central

    Ross, E L; Barker, J N; Allen, M H; Chu, A C; Groves, R W; MacDonald, D M

    1994-01-01

    Cellular adhesion molecules play a central role in leucocyte migration through peripheral blood and tissues. A crucial stage in these events in selectin-mediated adhesion involving E-selectin expressed on activated endothelium interacting with a range of carbohydrate ligands expressed by specific subpopulations of leucocytes. As such mechanisms may be relevant to bone marrow-derived dendritic epidermal Langerhans' cell (LC) migration, expression of these carbohydrate ligands was assessed immunocytochemically in whole skin biopsies and in epidermal cell suspensions obtained from adult humans. Double-labelling experiments revealed that sialyl Lewis x, recognized by the monoclonal antibody CSLEX1, was expressed on epidermal LC (n = 9). Furthermore, expression was enhanced at 24 hr following epicutaneous application of antigen and in the inflammatory disorder psoriasis (n = 10). E-selectin was concomitantly strongly expressed on dermal endothelium in psoriasis and allergic contact dermatitis. Intradermal injection of the T-cell-derived cytokine interferon-gamma (IFN-gamma) led to increased LC expression of sialyl Lewis x. In epidermal cell suspensions, in contrast to keratinocytes, CD1a+ cells expressed sialyl Lewis x, intensity of which was enhanced after 4 days in culture. CSLEX1 staining could be abolished and CD15 (non-sialated Lewis x) expression induced by saponification and treatment with neuraminidase. Expression of other selectin ligands was also examined. While the cutaneous lymphocyte antigen defined by the monoclonal antibody HECA-452 reacted with a small minority of LC, sialyl Lewis a and sulphatide were not expressed under any experimental conditions. These studies indicate that E-selectin-sialyl Lewis x interactions are potentially important in LC migration, both into and out of skin. Images Figure 2 Figure 3 Figure 5 Figure 6 PMID:7512530

  1. Ectopic ERK Expression Induces Phenotypic Conversion of C10 Cells and Alters DNA Methyltransferase Expression

    SciTech Connect

    Sontag, Ryan L.; Weber, Thomas J.

    2012-05-04

    In some model systems constitutive extracellular signal regulated kinase (ERK) activation is sufficient to promote an oncogenic phenotype. Here we investigate whether constitutive ERK expression influences phenotypic conversion in murine C10 type II alveolar epithelial cells. C10 cells were stably transduced with an ERK1-green fluorescent protein (ERK1-GFP) chimera or empty vector and ectopic ERK expression was associated with the acquisition of soft agar focus-forming potential in late passage, but not early passage cells. Late passage ERK1-GFP cells exhibited a significant increase in the expression of DNA methyl transferases (DNMT1 and 3b) and a marked increase in sensitivity to 5-azacytidine (5-azaC)-mediated toxicity, relative to early passage ERK1-GFP cells and vector controls. The expression of xeroderma pigmentosum complementation group A (XPA) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) were significantly increased in late passage cells, suggesting enhanced DNA damage recognition and repair activity which we interpret as a reflection of genomic instability. Phospho-ERK levels were dramatically decreased in late passage ERK1-GFP cells, relative to early passage and vector controls, and phospho-ERK levels were restored by treatment with sodium orthovanadate, indicating a role for phosphatase activity in this response. Collectively these observations suggest that ectopic ERK expression promotes phenotypic conversion of C10 cells that is associated with latent effects on epigenetic programming and phosphatase activities.

  2. An Exercise to Estimate Differential Gene Expression in Human Cells

    ERIC Educational Resources Information Center

    Chaudhry, M. Ahmad

    2006-01-01

    The expression of genes in cells of various tissue types varies considerably and is correlated with the function of a particular organ. The pattern of gene expression changes in diseased tissues, in response to therapy or infection and exposure to environmental mutagens, chemicals, ultraviolet light, and ionizing radiation. To better understand…

  3. Behavioral experience induces zif268 expression in mature granule cells but suppresses its expression in immature granule cells

    PubMed Central

    Huckleberry, Kylie A.; Kane, Gary A.; Mathis, Rita J.; Cook, Sarah G.; Clutton, Jonathan E.; Drew, Michael R.

    2015-01-01

    Thousands of neurons are born each day in the dentate gyrus (DG), but many of these cells die before reaching maturity. Both death and survival of adult-born neurons are regulated by neuronal activity in the DG. The immediate-early gene (IEG) zif268 appears to be an important mediator of these effects, as its expression can be induced by neural activity and knockout of zif268 impairs survival of adult-born neurons (Richardson et al., 1992; Veyrac et al., 2013). Despite the apparent importance of zif268 for adult neurogenesis, its behavior-induced expression has not been fully characterized in adult-born neurons. Here we characterize behavior-evoked expression of zif268 in mature and newborn dentate granule cells (DGCs). We first quantified zif268 expression in doublecortin-positive (DCX+) immature neurons and in the general granule cell population after brief exposure to a novel environment (NE). In the general granule cell population, zif268 expression peaked 1 h after NE exposure and returned to baseline by 8 h post-exposure. However, in the DCX+ cells, zif268 expression was suppressed relative to home cage for at least 8 h post-exposure. We next asked whether suppression of zif268 in DCX+ immature cells occurs in other behavioral paradigms that recruit the hippocampus. Exposure to Morris water maze (MWM) training, an enriched environment, or a NE caused approximately equal suppression of zif268 expression in DCX+ cells and approximately equal activation of zif268 expression among the general granule cell population. The same behavioral procedures activated zif268 expression in 6-week-old BrdU-labeled adult-born neurons, indicating that zif268 suppression is specific to immature neurons. Finally, we asked whether zif268 suppression varied as a function of age within the DCX+ population, which ranges in age from 0 to approximately 4 weeks. NE exposure had no significant effect on zif268 expression in 2- or 4-week-old BrdU-labeled neurons, but it significantly

  4. Neurogenin 3 Expressing Cells in the Human Exocrine Pancreas Have the Capacity for Endocrine Cell Fate

    PubMed Central

    Gomez, Danielle L.; O’Driscoll, Marci; Sheets, Timothy P.; Hruban, Ralph H.; Oberholzer, Jose; McGarrigle, James J.; Shamblott, Michael J.

    2015-01-01

    Neurogenin 3 (NGN3) is necessary and sufficient for endocrine differentiation during pancreatic development and is expressed by a population of progenitor cells that give rise exclusively to hormone-secreting cells within islets. NGN3 protein can be detected in the adult rodent pancreas only following certain types of injury, when it is transiently expressed by exocrine cells undergoing reprogramming to an endocrine cell fate. Here, NGN3 protein can be detected in 2% of acinar and duct cells in living biopsies of histologically normal adult human pancreata and 10% in cadaveric biopsies of organ donor pancreata. The percentage and total number of NGN3+ cells increase during culture without evidence of proliferation or selective cell death. Isolation of highly purified and viable NGN3+ cell populations can be achieved based on coexpression of the cell surface glycoprotein CD133. Transcriptome and targeted expression analyses of isolated CD133+ / NGN3+ cells indicate that they are distinct from surrounding exocrine tissue with respect to expression phenotype and Notch signaling activity, but retain high level mRNA expression of genes indicative of acinar and duct cell function. NGN3+ cells have an mRNA expression profile that resembles that of mouse early endocrine progenitor cells. During in vitro differentiation, NGN3+ cells express genes in a pattern characteristic of endocrine development and result in cells that resemble beta cells on the basis of coexpression of insulin C-peptide, chromogranin A and pancreatic and duodenal homeobox 1. NGN3 expression in the adult human exocrine pancreas marks a dedifferentiating cell population with the capacity to take on an endocrine cell fate. These cells represent a potential source for the treatment of diabetes either through ex vivo manipulation, or in vivo by targeting mechanisms controlling their population size and endocrine cell fate commitment. PMID:26288179

  5. Recombinant cells that highly express chromosomally-integrated heterologous genes

    DOEpatents

    Ingram, L.O.; Ohta, Kazuyoshi; Wood, B.E.

    1998-10-13

    Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol. 13 figs.

  6. Recombinant cells that highly express chromosomally-integrated heterologous gene

    DOEpatents

    Ingram, Lonnie O.; Ohta, Kazuyoshi; Wood, Brent E.

    2007-03-20

    Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol.

  7. Recombinant cells that highly express chromosomally-integrated heterologous genes

    DOEpatents

    Ingram, Lonnie O.; Ohta, Kazuyoshi; Wood, Brent E.

    1998-01-01

    Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol.

  8. Recombinant cells that highly express chromosomally-integrated heterologous genes

    DOEpatents

    Ingram, Lonnie O.; Ohta, Kazuyoshi; Wood, Brent E.

    2000-08-22

    Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol.

  9. Abnormally high expression of proteasomes in human leukemic cells.

    PubMed Central

    Kumatori, A; Tanaka, K; Inamura, N; Sone, S; Ogura, T; Matsumoto, T; Tachikawa, T; Shin, S; Ichihara, A

    1990-01-01

    Proteasomes are eukaryotic ring-shaped or cylindrical particles with multicatalytic protease activities. To clarify the involvement of proteasomes in tumorigenesis of human blood cells, we compared their expression in human hematopoietic malignant tumor cells with that in normal peripheral blood mononuclear cells. Immunohistochemical staining showed considerably increased concentrations of proteasomes in leukemic cells from the bone marrow of patients with various types of leukemia and the predominant localization of these proteasomes in the nuclei. Moreover, enzyme immunoassay and Northern blot analysis indicated that the concentrations of proteasomes and their mRNA levels were consistently much higher in a variety of malignant human hematopoietic cell lines than in resting peripheral lymphocytes and monocytes from healthy adults. Proteasome expression was also greatly increased in normal blood mononuclear cells during blastogenic transformation induced by phytohemagglutinin; their expression increased in parallel with induction of DNA synthesis and returned to the basal level with progress of the cell cycle. Thus, abnormally high expression of proteasomes may play an important role in transformation and proliferation of blood cells and in specific functions of hematopoietic tumor cells. Images PMID:2205851

  10. Differential expression of estrogen receptor α and progesterone receptor in the normal and cryptorchid testis of a dog.

    PubMed

    Jung, Hyo Young; Yoo, Dae Young; Jo, Young Kwang; Kim, Geon A; Chung, Jin Young; Choi, Jung Hoon; Jang, Goo; Hwang, In Koo

    2016-06-01

    Descending of the testes is an important process for spermatogenesis and cryptorchidism is one of the most relevant genital defects in dogs. In a previous study, we observed abnormal morphology and proliferation of Sertoli cells in a cryptorchid testis. In the present study, we investigated the expression of estrogen and progesterone receptors in the normal and cryptorchid testis of a dog. Elective orchidectomy was performed on the dog's abdominal right testis (undescended, cryptorchid) and scrotal left testis (descended, normal). In the normal testis, estrogen receptor α immunoreactivity was detected in Leydig cells alone, while estrogen receptor α immunoreactivity in the cryptorchid testis was significantly prominent in the Sertoli cells as well. In addition, progesterone receptor immunoreactivity in the control testis was detected in the spermatids, but was not detected in the cryptorchid testis. This result suggests that unilateral cryptorchidism causes increases of estrogen receptor α expression in Sertoli cells. PMID:27382382

  11. Differential expression of estrogen receptor α and progesterone receptor in the normal and cryptorchid testis of a dog

    PubMed Central

    Jung, Hyo Young; Yoo, Dae Young; Jo, Young Kwang; Kim, Geon A; Chung, Jin Young; Choi, Jung Hoon

    2016-01-01

    Descending of the testes is an important process for spermatogenesis and cryptorchidism is one of the most relevant genital defects in dogs. In a previous study, we observed abnormal morphology and proliferation of Sertoli cells in a cryptorchid testis. In the present study, we investigated the expression of estrogen and progesterone receptors in the normal and cryptorchid testis of a dog. Elective orchidectomy was performed on the dog's abdominal right testis (undescended, cryptorchid) and scrotal left testis (descended, normal). In the normal testis, estrogen receptor α immunoreactivity was detected in Leydig cells alone, while estrogen receptor α immunoreactivity in the cryptorchid testis was significantly prominent in the Sertoli cells as well. In addition, progesterone receptor immunoreactivity in the control testis was detected in the spermatids, but was not detected in the cryptorchid testis. This result suggests that unilateral cryptorchidism causes increases of estrogen receptor α expression in Sertoli cells. PMID:27382382

  12. Amino Acids Regulate Transgene Expression in MDCK Cells

    PubMed Central

    Torrente, Marta; Guetg, Adriano; Sass, Jörn Oliver; Arps, Lisa; Ruckstuhl, Lisa; Camargo, Simone M. R.; Verrey, François

    2014-01-01

    Gene expression and cell growth rely on the intracellular concentration of amino acids, which in metazoans depends on extracellular amino acid availability and transmembrane transport. To investigate the impact of extracellular amino acid concentrations on the expression of a concentrative amino acid transporter, we overexpressed the main kidney proximal tubule luminal neutral amino acid transporter B0AT1-collectrin (SLC6A19-TMEM27) in MDCK cell epithelia. Exogenously expressed proteins co-localized at the luminal membrane and mediated neutral amino acid uptake. However, the transgenes were lost over few cell culture passages. In contrast, the expression of a control transgene remained stable. To test whether this loss was due to inappropriately high amino acid uptake, freshly transduced MDCK cell lines were cultivated either with physiological amounts of amino acids or with the high concentration found in standard cell culture media. Expression of exogenous transporters was unaffected by physiological amino acid concentration in the media. Interestingly, mycoplasma infection resulted in a significant increase in transgene expression and correlated with the rapid metabolism of L-arginine. However, L-arginine metabolites were shown to play no role in transgene expression. In contrast, activation of the GCN2 pathway revealed by an increase in eIF2α phosphorylation may trigger transgene derepression. Taken together, high extracellular amino acid concentration provided by cell culture media appears to inhibit the constitutive expression of concentrative amino acid transporters whereas L-arginine depletion by mycoplasma induces the expression of transgenes possibly via stimulation of the GCN2 pathway. PMID:24797296

  13. UV-induced changes in cell cycle and gene expression within rabbit lens epithelial cells

    SciTech Connect

    Sidjanin, D.; Grdina, D.; Woloschak, G.E.

    1994-11-01

    Damage to lens epithelial cells is a probable initiation process in cataract formation induced by ultraviolet radiation. These experiments investigated the ability of 254 nm radiation on cell cycle progression and gene expression in rabbit lens epithelial cell line N/N1003A. No changes in expression of c-fos, c-jun, alpha- tubulin, or vimentin was observed following UV exposure. Using flow cytometry, an accumulation of cells in G1/S phase of the cell cycle 1 hr following exposure. The observed changes in gene expression, especially the decreased histone transcripts reported here may play a role in UV induced inhibition of cell cycle progression.

  14. Expression and purification of recombinant nattokinase in Spodoptera frugiperda cells.

    PubMed

    Li, Xiaoxiang; Wang, Xiaoli; Xiong, Shaoling; Zhang, Jing; Cai, Litao; Yang, Yanyan

    2007-10-01

    A recombinant baculovirus, rv-egfp-NK, containing a reporter gene encoding the enhanced green fluorescent protein (EGFP), was used to express nattokinase (NK), a fibrinolytic enzyme, in Spodoptera frugiperda (SF-9) cells. The recombinant protein also included a histidine tag for purification using Ni(2+) resins. The recombinant NK, approximately 30 kDa, retained fibrinolytic activity (60 U/ml). The integration of the EGFP expression cassette in the Bac-to-Bac system is thus an effective method for the expression and purification of recombinant NK protein in Spodoptera frugiperda insect cells. PMID:17581705

  15. Human rhabdomyosarcoma cells express functional erythropoietin receptor: Potential therapeutic implications

    PubMed Central

    PONIEWIERSKA-BARAN, AGATA; SUSZYNSKA, MALWINA; SUN, WENYUE; ABDELBASET-ISMAIL, AHMED; SCHNEIDER, GABRIELA; BARR, FREDERIC G.; RATAJCZAK, MARIUSZ Z.

    2015-01-01

    The erythropoietin receptor (EpoR) is expressed by cells from the erythroid lineage; however, evidence has accumulated that it is also expressed by some solid tumors. This is an important observation, because recombinant erythropoietin (EPO) is employed in cancer patients to treat anemia related to chemo/radiotherapy. In our studies we employed eight rhabdomyosarcoma (RMS) cell lines (three alveolar-type RMS cell lines and five embrional-type RMS cell lines), and mRNA samples obtained from positive, PAX7-FOXO1-positive, and fusion-negative RMS patient samples. Expression of EpoR was evaluated by RT-PCR, gene array and FACS. The functionality of EpoR in RMS cell lines was evaluated by chemotaxis, adhesion, and direct cell proliferation assays. In some of the experiments, RMS cells were exposed to vincristine (VCR) in the presence or absence of EPO to test whether EPO may impair the therapeutic effect of VCR. We report for a first time that functional EpoR is expressed in human RMS cell lines as well as by primary tumors from RMS patients. Furthermore, EpoR is detectably expressed in both embryonal and alveolar RMS subtypes. At the functional level, several human RMS cell lines responded to EPO stimulation by enhanced proliferation, chemotaxis, cell adhesion, and phosphorylation of MAPKp42/44 and AKT. Moreover, RMS cells became more resistant to VCR treatment in the presence of EPO. Our findings have important potential clinical implications, indicating that EPO supplementation in RMS patients may have the unwanted side effect of tumor progression. PMID:26412593

  16. Human rhabdomyosarcoma cells express functional erythropoietin receptor: Potential therapeutic implications.

    PubMed

    Poniewierska-Baran, Agata; Suszynska, Malwina; Sun, Wenyue; Abdelbaset-Ismail, Ahmed; Schneider, Gabriela; Barr, Frederic G; Ratajczak, Mariusz Z

    2015-11-01

    The erythropoietin receptor (EpoR) is expressed by cells from the erythroid lineage; however, evidence has accumulated that it is also expressed by some solid tumors. This is an important observation, because recombinant erythropoietin (EPO) is employed in cancer patients to treat anemia related to chemo/radiotherapy. In our studies we employed eight rhabdomyosarcoma (RMS) cell lines (three alveolar-type RMS cell lines and five embrional-type RMS cell lines), and mRNA samples obtained from positive, PAX7-FOXO1-positive, and fusion-negative RMS patient samples. Expression of EpoR was evaluated by RT-PCR, gene array and FACS. The functionality of EpoR in RMS cell lines was evaluated by chemotaxis, adhesion, and direct cell proliferation assays. In some of the experiments, RMS cells were exposed to vincristine (VCR) in the presence or absence of EPO to test whether EPO may impair the therapeutic effect of VCR. We report for a first time that functional EpoR is expressed in human RMS cell lines as well as by primary tumors from RMS patients. Furthermore, EpoR is detectably expressed in both embryonal and alveolar RMS subtypes. At the functional level, several human RMS cell lines responded to EPO stimulation by enhanced proliferation, chemotaxis, cell adhesion, and phosphorylation of MAPKp42/44 and AKT. Moreover, RMS cells became more resistant to VCR treatment in the presence of EPO. Our findings have important potential clinical implications, indicating that EPO supplementation in RMS patients may have the unwanted side effect of tumor progression. PMID:26412593

  17. Magnetic field-controlled gene expression in encapsulated cells

    PubMed Central

    Ortner, Viktoria; Kaspar, Cornelius; Halter, Christian; Töllner, Lars; Mykhaylyk, Olga; Walzer, Johann; Günzburg, Walter H.; Dangerfield, John A.; Hohenadl, Christine; Czerny, Thomas

    2012-01-01

    Cell and gene therapies have an enormous range of potential applications, but as for most other therapies, dosing is a critical issue, which makes regulated gene expression a prerequisite for advanced strategies. Several inducible expression systems have been established, which mainly rely on small molecules as inducers, such as hormones or antibiotics. The application of these inducers is difficult to control and the effects on gene regulation are slow. Here we describe a novel system for induction of gene expression in encapsulated cells. This involves the modification of cells to express potential therapeutic genes under the control of a heat inducible promoter and the co-encapsulation of these cells with magnetic nanoparticles. These nanoparticles produce heat when subjected to an alternating magnetic field; the elevated temperatures in the capsules then induce gene expression. In the present study we define the parameters of such systems and provide proof-of-principle using reporter gene constructs. The fine-tuned heating of nanoparticles in the magnetic field allows regulation of gene expression from the outside over a broad range and within short time. Such a system has great potential for advancement of cell and gene therapy approaches. PMID:22197778

  18. Leukomogenic factors downregulate heparanase expression in acute myeloid leukemia cells

    SciTech Connect

    Eshel, Rinat; Ben-Zaken, Olga; Vainas, Oded; Nadir, Yona; Minucci, Saverio; Polliack, Aaron; Naparstek, Ella; Vlodavsky, Israel; Katz, Ben-Zion; E-mail: bkatz@tasmc.healt.gov.il

    2005-10-07

    Heparanase is a heparan sulfate-degrading endoglycosidase expressed by mature monocytes and myeloid cells, but not by immature hematopoietic progenitors. Heparanase gene expression is upregulated during differentiation of immature myeloid cells. PML-RAR{alpha} and PLZF-RAR{alpha} fusion gene products associated with acute promyelocytic leukemia abrogate myeloid differentiation and heparanase expression. AML-Eto, a translocation product associated with AML FAB M2, also downregulates heparanase gene expression. The common mechanism that underlines the activity of these three fusion gene products involves the recruitment of histone deacetylase complexes to specific locations within the DNA. We found that retinoic acid that dissociates PML-RAR{alpha} from the DNA, and which is used to treat acute promyelocytic leukemia patients, restores heparanase expression to normal levels in an acute promyelocytic leukemia cell line. The retinoic acid effects were also observed in primary acute promyelocytic leukemia cells and in a retinoic acid-treated acute promyelocytic leukemia patient. Histone deacetylase inhibitor reverses the downregulation of heparanase expression induced by the AML-Eto fusion gene product in M2 type AML. In summary, we have characterized a link between leukomogenic factors and the downregulation of heparanase in myeloid leukemic cells.

  19. Inducible regulation of GDNF expression in human neural stem cells.

    PubMed

    Wang, ShuYan; Ren, Ping; Guan, YunQian; Zou, ChunLin; Fu, LinLin; Zhang, Yu

    2013-01-01

    Glial cell derived neurotrophic factor (GDNF) holds promises for treating neurodegenerative diseases such as Parkinson's disease. Human neural stem cells (hNSCs) have proved to be a suitable cell delivery vehicle for the safe and efficient introduction of GDNF into the brain. In this study, we used hNSCs-infected with a lentivirus encoding GDNF and the hygromycin resistance gene as such vehicles. A modified tetracycline operator 7 (tetO7) was inserted into a region upstream of the EF1-α promoter to drive GDNF expression. After hygromycin selection, hNSCs were infected with a lentivirus encoding a KRAB-tetracycline repressor fusion protein (TTS). TTS bound to tetO7 and suppressed the expression of GDNF in hNSCs. Upon administration of doxycycline (Dox) the TTS-tetO7 complex separated and the expression of GDNF resumed. The hNSCs infected with GDNF expressed the neural stem cell specific markers, nestin and sox2, and exhibited no significant change in proliferation rate. However, the rate of apoptosis in hNSCs expressing GDNF was lower compared with normal NSCs in response to actinomycin treatment. Furthermore, a higher percentage of Tuj-1 positive cells were obtained from GDNF-producing NSCs under conditions that induced differentiation compared to control NSCs. The inducible expression of GDNF in hNSCs may provide a system for the controllable delivery of GDNF in patients with neurodegenerative diseases. PMID:23269553

  20. All-optical regulation of gene expression in targeted cells

    NASA Astrophysics Data System (ADS)

    Wang, Yisen; He, Hao; Li, Shiyang; Liu, Dayong; Lan, Bei; Hu, Minglie; Cao, Youjia; Wang, Chingyue

    2014-06-01

    Controllable gene expression is always a challenge and of great significance to biomedical research and clinical applications. Recently, various approaches based on extra-engineered light-sensitive proteins have been developed to provide optogenetic actuators for gene expression. Complicated biomedical techniques including exogenous genes engineering, transfection, and material delivery are needed. Here we present an all-optical method to regulate gene expression in targeted cells. Intrinsic or exogenous genes can be activated by a Ca2+-sensitive transcription factor nuclear factor of activated T cells (NFAT) driven by a short flash of femtosecond-laser irradiation. When applied to mesenchymal stem cells, expression of a differentiation regulator Osterix can be activated by this method to potentially induce differentiation of them. A laser-induced ``Ca2+-comb'' (LiCCo) by multi-time laser exposure is further developed to enhance gene expression efficiency. This noninvasive method hence provides an encouraging advance of gene expression regulation, with promising potential of applying in cell biology and stem-cell science.

  1. Estradiol regulates MICA expression in human endometrial cells

    PubMed Central

    Basu, Satarupa; Pioli, Patricia A.; Conejo-Garcia, Jose; Wira, Charles R.; Sentman, Charles L.

    2008-01-01

    The human endometrium undergoes cyclical changes regulated by sex hormones. Evidence suggests sex hormones regulate NK cell recruitment into the uterus in large numbers. NKG2D is an activating receptor expressed on human NK cells, γδ and CD8 T cells. NKG2D ligands are known to be sensors of cellular “stress”. In this study, we investigated whether sex hormones directly regulate expression of NKG2D ligands in the human uterus. Estradiol increased MICA expression on uterine epithelial cells; regulation was estrogen receptor-dependent. Real-time PCR analysis showed that NKG2D ligands MICA and MICB were expressed in the human endometrium. MICA protein was detected primarily on epithelial cells, and greater expression was observed in immunohistochemical analysis of tissues from patients in the secretory phase of the menstrual cycle. Thus, estrogens regulate expression of MICA. These data suggest hormonal regulation of innate immunity and NKG2D-mediated recognition in other tissues and diseases where estrogen may be involved. PMID:18728002

  2. The expression of ADAMTS13 in human microvascular endothelial cells.

    PubMed

    Wang, Anyou; Duan, Qiaohong; Wu, Jingsheng; Liu, Xin; Sun, Zimin

    2016-06-01

    ADAMTS13, as a specific von Willebrand factor (VWF)-cleaving protease, prevents microvascular thrombosis of VWF/platelet thrombi. It has been reported that human vascular endothelial cells could also synthesize and secrete ADAMTS13, and these reports were focused in human umbilical vascular endothelial cells. Considering the particularity of its huge quantity and structure of human microvascular endothelial cells (HMECs) in the body, whether ADAMTS13 is expressed in HMECs also needs to be confirmed. To investigate whether ADAMTS13 is expressed in HMECs. Real-time PCR (RT-PCR) amplification detected ADAMTS13 mRNA in HMEC-1 cell line. The expression and distribution of ADAMTS13 protein and VWF were detected by fluorescence immunoassay and western blot. We observed the expression and distribution of ADAMTS13 in HMECs. We confirmed the expression of ADAMTS13 mRNA in HMEC-1, and found that there were some partly common distributions of ADAMTS13 protein and VWF. This study provides the evidence that HMECs also express ADAMTS13. HMECs might also be a primary source for human plasma ADAMTS13. The overlap region for the distribution of ADAMTS13 and VWF suggests that ADAMTS13 might have a potential regulation role for VWF inside cells. PMID:26366828

  3. Expression of the somatostatin gene in human astrocytoma cell lines.

    PubMed Central

    Mercure, L; Tannenbaum, G S; Schipper, H M; Phaneuf, D; Wainberg, M A

    1996-01-01

    Somatostatin (somatotropin release-inhibiting hormone; SRIH) has been demonstrated in neurons of the central nervous system (CNS) as well as in endocrine cells of the pancreas and gastrointestinal tract and can suppress various immune functions including lymphocyte proliferation, immunoglobulin synthesis, and cytokine production. Since astrocytes possess antigen-presenting activity and can secrete a wide array of immunoregulatory and inflammatory cytokines, we studied SRIH gene expression in both astrocyte cell lines and mitogen-stimulated peripheral blood mononuclear leukocytes from healthy donors. We now report by means of a complementary DNA-based reverse transcription PCR that differential levels of SRIH mRNA were expressed in 9 of 11 human astrocytoma cell lines tested but were undetectable in activated peripheral blood mononuclear leukocytes as well as in a variety of human lymphocyte and monocyte cell lines. The synthesis and secretion of SRIH protein by astrocytoma cells that expressed SRIH transcripts were confirmed by specific radioimmunoassay of cell culture fluids. These findings support the notion that SRIH gene expression occurs in human astrocytoma cells but not in mature lymphoid cells of the immune system. PMID:8991628

  4. PAX8 Expression in Ovarian Surface Epithelial Cells

    PubMed Central

    Adler, Emily; Mhawech-Fauceglia, Paulette; Gayther, Simon A; Lawrenson, Kate

    2015-01-01

    High-grade serous ovarian carcinoma (HGSOC) is usually diagnosed at a late stage and is associated with poor prognosis. Understanding early stage disease biology is essential in developing clinical biomarkers to detect HGSOC earlier. While recent studies indicate that HGSOCs arise from fallopian tube secretory epithelial cells (FTSECs), a considerable body of evidence also suggests that HGSOC can also arise from ovarian surface epithelial cells (OSECs). PAX8 is overexpressed in HGSOCs and expressed in FTSECs, but there are conflicting reports about PAX8 expression in OSECs. The purpose of this study was to comprehensively characterize PAX8 expression in a large series of OSECs, and to investigate the role of PAX8 in early HGSOC development. PAX8 protein expression was analyzed in the OSECs of 27 normal ovaries and 7 primary OSEC cultures using immunohistochemistry and immunofluorescent cytochemistry. PAX8 mRNA expression was quantified in 66 primary OSEC cultures. Cellular transformation was evaluated in OSECs expressing a PAX8 construct. PAX8 was expressed by 44-71% of OSECs. Calretinin and E-cadherin were frequently co-expressed with PAX8. Expression of PAX8 in OSECs decreased cellular migration (P=0.028), but had no other effects on cellular transformation. In addition, PAX8 expression was significantly increased (P=0.003) in an in vitro stepwise model of neoplastic transformation. In conclusion, PAX8 is frequently expressed by OSECs and endogenous levels of PAX8 expression are non-transforming. These data indicate that in OSECs PAX8 expression may represent a normal state and that OSECs may represent an origin of HGSOCs. PMID:26079312

  5. HLA antigen expression in enteropathy associated T cell lymphoma.

    PubMed Central

    Ashton-Key, M; Singh, N; Pan, L X; Smith, M E

    1996-01-01

    AIMS: To investigate the occurrence of abnormal patterns of HLA-ABC and HLA-DR expression in enteropathy associated T cell lymphoma and to relate such abnormalities to the Epstein Barr virus (EBV) status of the tumours. METHODS: Eleven enteropathy associated T cell lymphomas were immunostained with HC10 (HLA-ABC heavy chain) and TAL 1B5 (HLA-DR alpha chain) monoclonal antibodies and polyclonal anti-beta 2 microglobulin (beta 2m, the HLA-ABC light chain) antibodies. In situ hybridisation for EBV using EBER probes was performed on all cases. RESULTS: Tumour cells of two of 11 patients were EBER positive. One of these showed partial, and the other, complete loss of beta 2m. HLA-DR expression was undetectable in both patients. Of the remaining nine EBER negative tumours, two were HLA-ABC heavy chain negative or showed only occasional positive cells and five of nine showed partial or complete loss of the HLA-ABC light chain, beta 2m. Seven of the nine cases were either negative for HLA-DR or showed weak expression in a proportion of tumour cells. CONCLUSIONS: These data show that low or absent HLA-ABC and HLA-DR antigen expression occurs commonly in enteropathy associated T cell lymphoma. These abnormal patterns of HLA expression may be associated with escape from immune attack which, in a minority of patients, could be directed against EBV antigens. Images PMID:8813950

  6. Cell-Free Expression of G Protein-Coupled Receptors.

    PubMed

    Segers, Kenneth; Masure, Stefan

    2015-01-01

    The large-scale production of recombinant G protein-coupled receptors (GPCRs) is one of the major bottlenecks that hamper functional and structural studies of this important class of integral membrane proteins. Heterologous overexpression of GPCRs often results in low yields of active protein, usually due to a combination of several factors, such as low expression levels, protein insolubility, host cell toxicity, and the need to use harsh and often denaturing detergents (e.g., SDS, LDAO, OG, and DDM, among others) to extract the recombinant receptor from the host cell membrane. Many of these problematic issues are inherently linked to cell-based expression systems and can therefore be circumvented by the use of cell-free systems. In this unit, we provide a range of protocols for the production of GPCRs in a cell-free expression system. Using this system, we typically obtain GPCR expression levels of ∼1 mg per ml of reaction mixture in the continuous-exchange configuration. Although the protocols in this unit have been optimized for the cell-free expression of GPCRs, they should provide a good starting point for the production of other classes of membrane proteins, such as ion channels, aquaporins, carrier proteins, membrane-bound enzymes, and even large molecular complexes. PMID:26237676

  7. Expression profiling. Combinatorial labeling of single cells for gene expression cytometry.

    PubMed

    Fan, H Christina; Fu, Glenn K; Fodor, Stephen P A

    2015-02-01

    We present a technically simple approach for gene expression cytometry combining next-generation sequencing with stochastic barcoding of single cells. A combinatorial library of beads bearing cell- and molecular-barcoding capture probes is used to uniquely label transcripts and reconstruct the digital gene expression profile of thousands of individual cells in a single experiment without the need for robotics or automation. We applied the technology to dissect the human hematopoietic system and to characterize heterogeneous response to in vitro stimulation. High sensitivity is demonstrated by detection of low-abundance transcripts and rare cells. Under current implementation, the technique can analyze a few thousand cells simultaneously and can readily scale to 10,000s or 100,000s of cells. PMID:25657253

  8. Significance of Parafibromin Expression in Laryngeal Squamous Cell Carcinomas

    PubMed Central

    Cho, Inju; Lee, Mija; Lim, Sharon; Hong, Ran

    2016-01-01

    Background: Parafibromin is a product of the tumor suppressor gene that has been studied as a potential indicator of tumor aggressiveness in the parathyroid, breast, colorectum, and stomach. However, the clinical significance and potential function of parafibromin expression in head and neck squamous cell carcinomas remain largely unknown. The aim of this study was to evaluate the expression of parafibromin in laryngeal squamous cell carcinoma (LSCC) and to verify its potential as a biomarker of tumor behavior. Methods: Parafibromin expression was evaluated in 30 cases of LSCC using immunohistochemistry. The correlations between parafibromin expression and clinicopathologic parameters were investigated. Results: Parafibromin expression was positive in 15 cases (50%) and negative in 15 cases (50%). Tumor size and T stage showed a statistically significant inverse relationship with parafibromin expression (p=.028 and p<.001, respectively). Parafibromin expression was not associated with age, sex, lymph node metastasis, tumor differentiation, or tumor location. There was no statistically significant relationship between parafibromin expression and progression-free survival in the patients (p>.05). Conclusions: Our results indicate that the downregulation or loss of parafibromin expression can be employed as a novel marker of tumor progression or aggressiveness in LSCC. PMID:27334641

  9. B cell priming for extrafollicular antibody responses requires Bcl-6 expression by T cells.

    PubMed

    Lee, Sau K; Rigby, Robert J; Zotos, Dimitra; Tsai, Louis M; Kawamoto, Shimpei; Marshall, Jennifer L; Ramiscal, Roybel R; Chan, Tyani D; Gatto, Dominique; Brink, Robert; Yu, Di; Fagarasan, Sidonia; Tarlinton, David M; Cunningham, Adam F; Vinuesa, Carola G

    2011-07-01

    T follicular helper cells (Tfh cells) localize to follicles where they provide growth and selection signals to mutated germinal center (GC) B cells, thus promoting their differentiation into high affinity long-lived plasma cells and memory B cells. T-dependent B cell differentiation also occurs extrafollicularly, giving rise to unmutated plasma cells that are important for early protection against microbial infections. Bcl-6 expression in T cells has been shown to be essential for the formation of Tfh cells and GC B cells, but little is known about its requirement in physiological extrafollicular antibody responses. We use several mouse models in which extrafollicular plasma cells can be unequivocally distinguished from those of GC origin, combined with antigen-specific T and B cells, to show that the absence of T cell-expressed Bcl-6 significantly reduces T-dependent extrafollicular antibody responses. Bcl-6(+) T cells appear at the T-B border soon after T cell priming and before GC formation, and these cells express low amounts of PD-1. Their appearance precedes that of Bcl-6(+) PD-1(hi) T cells, which are found within the GC. IL-21 acts early to promote both follicular and extrafollicular antibody responses. In conclusion, Bcl-6(+) T cells are necessary at B cell priming to form extrafollicular antibody responses, and these pre-GC Tfh cells can be distinguished phenotypically from GC Tfh cells. PMID:21708925

  10. SPARC expression induces cell cycle arrest via STAT3 signaling pathway in medulloblastoma cells

    SciTech Connect

    Chetty, Chandramu; Dontula, Ranadheer; Gujrati, Meena; Lakka, Sajani S.

    2012-01-13

    Highlights: Black-Right-Pointing-Pointer Ectopic expression of SPARC impaired cell proliferation in medulloblastoma cells. Black-Right-Pointing-Pointer SPARC expression induces STAT3 mediated cell cycle arrest in medulloblastoma cells. Black-Right-Pointing-Pointer SPARC expression significantly inhibited pre-established tumor growth in nude-mice. -- Abstract: Dynamic cell interaction with ECM components has profound influence in cancer progression. SPARC is a component of the ECM, impairs the proliferation of different cell types and modulates tumor cell aggressive features. We previously reported that SPARC expression significantly impairs medulloblastoma tumor growth in vivo. In this study, we demonstrate that expression of SPARC inhibits medulloblastoma cell proliferation. MTT assay indicated a dose-dependent reduction in tumor cell proliferation in adenoviral mediated expression of SPARC full length cDNA (Ad-DsRed-SP) in D425 and UW228 cells. Flow cytometric analysis showed that Ad-DsRed-SP-infected cells accumulate in the G2/M phase of cell cycle. Further, immunoblot and immunoprecipitation analyses revealed that SPARC induced G2/M cell cycle arrest was mediated through inhibition of the Cyclin-B-regulated signaling pathway involving p21 and Cdc2 expression. Additionally, expression of SPARC decreased STAT3 phosphorylation at Tyr-705; constitutively active STAT3 expression reversed SPARC induced G2/M arrest. Ad-DsRed-SP significantly inhibited the pre-established orthotopic tumor growth and tumor volume in nude-mice. Immunohistochemical analysis of tumor sections from mice treated with Ad-DsRed-SP showed decreased immunoreactivity for pSTAT3 and increased immunoreactivity for p21 compared to tumor section from mice treated with mock and Ad-DsRed. Taken together our studies further reveal that STAT3 plays a key role in SPARC induced G2/M arrest in medulloblastoma cells. These new findings provide a molecular basis for the mechanistic understanding of the

  11. 293 cells express both epithelial as well as mesenchymal cell adhesion molecules

    PubMed Central

    INADA, MASAKAZU; IZAWA, GENYA; KOBAYASHI, WAKAKO; OZAWA, MASAYUKI

    2016-01-01

    The 293 cell line, used extensively in various types of studies due to the ease with which these cells can be transfected, was thought to be derived by the transformation of primary cultures of human embryonic kidney cells with sheared adenovirus type 5 DNA. Although the 293 cells were assumed to originate from epithelial cells, the exact origin of these cells remains unknown. Previous attempts to characterize these cells combined immunostaining, immunoblot analysis and microarray analysis to demonstrate that 293 cells express neurofilament subunits, α-internexin, and several other proteins typically found in neurons. These findings raised the possibility that the 293 cell line may have originated from human neuronal lineage cells. Contrary to this suggestion, in this study, we found that the 293 cells expressed N-cadherin and vimentin, which are marker proteins expressed in mesenchymal cells. Furthermore, the 293 cells also expressed E-cadherin, cytokeratins 5/8 and desmoglein 2, which are epithelial cell markers. When the cells, primarily cultured from the kidneys of Clawn miniature swine and passaged 10–15 generations [termed porcine kidney epithelial (PKE) cells] were examined, they were found to be positive for the expression of both mesenchymal and epithelial markers. Thus, transformation by adenovirus was not necessary for the cells to express N-cadherin. Occludin and zonula occludens (ZO)-1, two components of tight junctions in epithelial and endothelial cells, were detected in the 293 and the PKE cells. Thus, the findings of the present study demonstrate that 293 cells retain several characteristics of epithelial cells. PMID:27121032

  12. Reduced Ang2 expression in aging endothelial cells.

    PubMed

    Hohensinner, P J; Ebenbauer, B; Kaun, C; Maurer, G; Huber, K; Wojta, J

    2016-06-01

    Aging endothelial cells are characterized by increased cell size, reduced telomere length and increased expression of proinflammatory cytokines. In addition, we describe here that aging reduces the migratory distance of endothelial cells. Furthermore, we observe an increase of the quiescence protein Ang1 and a decrease of the endothelial activation protein Ang2 upon aging. Supplementing Ang2 to aged endothelial cells restored their migratory capacity. We conclude that aging shifts the balance of the Ang1/Ang2 network favouring a quiescent state. Activation of endothelial cells in aging might be necessary to enhance wound healing capacities. PMID:27137842

  13. Immunoglobulin Expression in Non-Lymphoid Lineage and Neoplastic Cells

    PubMed Central

    Chen, Zhengshan; Qiu, Xiaoyan; Gu, Jiang

    2009-01-01

    It has traditionally been believed that the production of immunoglobulin (Ig) molecules is restricted to B lineage cells. However, immunoglobulin genes and proteins have been recently found in a variety of types of cancer cells, as well as some proliferating epithelial cells and neurons. The immunoglobulin molecules expressed by these cells consist predominantly of IgG, IgM, and IgA, and the light chains expressed are mainly kappa chains. Recombination activating genes 1 and 2, which are required for V(D)J recombination, are also expressed in these cells. Knowledge about the function of these non-lymphoid cell-derived immunoglobulins is limited. Preliminary data suggests that Ig secreted by epithelial cancer cells has some unidentified capacity to promote the growth and survival of tumor cells. As immunoglobulins are known to have a wide spectrum of important functions, the discovery of non-lymphoid cells and cancers that produce immunoglobulin calls for in-depth investigation of the functional and pathological significance of this previously unrecognized phenomenon. PMID:19246641

  14. Survivin expression is associated with lens epithelial cell proliferation and fiber cell differentiation

    PubMed Central

    Mansergh, Fiona C.; Boulton, Michael E.; Gunhaga, Lena

    2012-01-01

    Purpose Survivin (Birc5) is the smallest member of the inhibitor of apoptosis (IAP) protein family, which regulates the cell cycle/apoptosis balance. The purpose of this study was to examine Survivin expression in the embryonic chick lens, in chick lens epithelial cell cultures, and in the postnatal mouse lens. Methods Survivin expression was examined using a combination of quantitative real-time polymerase chain reaction, western blotting, and immunocytochemistry. To correlate Survivin expression with the timing of proliferation, we determined the profile of cell proliferation in the developing lens using the cell cycle marker proliferating cell nuclear antigen (PCNA) in quantitative western blotting and immunocytochemistry studies. We also examined the expression of PCNA and the extent of denucleation using terminal deoxynucleotidyl transferase (TdT)-mediated biotin-dUTP nick-end labeling (TUNEL) of lentoids (lens fiber-like cells) during chick lens epithelial cell differentiation in vitro. Results At embryonic day (ED) 4, Survivin immunostaining was present in two pools in lens epithelial cells and fiber cells: cytoplasmic and nuclear. The nuclear staining became more pronounced as the lens epithelial cells differentiated into lens fiber cells. At ED12, Survivin staining was observed in lens fiber cell nuclei containing marginalized chromatin, indicative of early denucleation events. Using western blotting, Survivin expression peaked at ED6, diminishing thereafter. This profile of expression correlated with the events in chick lens epithelial cell cultures: i) increased Survivin expression was associated with an increase in PCNA staining up to day 6 of culture and ii) downregulation of Survivin expression at day 8 of culture was coincident with a dramatic decrease in PCNA staining and an increase in TdT-mediated biotin-dUTP nick-end labeling in lentoids. In early postnatal mouse lenses, Survivin and PCNA were highly expressed and decreased thereafter during

  15. Enhanced expression of codon optimized interferon gamma in CHO cells.

    PubMed

    Chung, Bevan Kai-Sheng; Yusufi, Faraaz N K; Mariati; Yang, Yuansheng; Lee, Dong-Yup

    2013-09-10

    The human interferon-gamma (IFN-γ) is a potential drug candidate for treating various diseases due to its immunomodulatory properties. The efficient production of this protein can be achieved through a popular industrial host, Chinese hamster ovary (CHO) cells. However, recombinant expression of foreign proteins is typically suboptimal possibly due to the usage of non-native codon patterns within the coding sequence. Therefore, we demonstrated the application of a recently developed codon optimization approach to design synthetic IFN-γ coding sequences for enhanced heterologous expression in CHO cells. For codon optimization, earlier studies suggested to establish the target usage distribution pattern in terms of selected design parameters such as individual codon usage (ICU) and codon context (CC), mainly based on the host's highly expressed genes. However, our RNA-Seq based transcriptome profiling indicated that the ICU and CC distribution patterns of different gene expression classes in CHO cell are relatively similar, unlike other microbial expression hosts, Escherichia coli and Saccharomyces cerevisiae. This finding was further corroborated through the in vivo expression of various ICU and CC optimized IFN-γ in CHO cells. Interestingly, the CC-optimized genes exhibited at least 13-fold increase in expression level compared to the wild-type IFN-γ while a maximum of 10-fold increase was observed for the ICU-optimized genes. Although design criteria based on individual codons, such as ICU, have been widely used for gene optimization, our experimental results suggested that codon context is relatively more effective parameter for improving recombinant IFN-γ expression in CHO cells. PMID:23876479

  16. Expression and stabilization of bacterial luciferase in mammalian cells

    NASA Astrophysics Data System (ADS)

    Patterson, Stacey S.; Dionisi, Hebe M.; Gupta, Rakesh K.; Sayler, Gary S.

    2004-06-01

    Current mammalian bioreporters using either firefly luciferase (luc) or GFP constructs require lysis and/or exogenous excitation to evoke a measurable response. Consequently, these cells cannot serve as continuous, on-line monitoring devices for in vivo imaging. Bacterial luciferase, lux, produces a photonic reaction that is cyclic, resulting in autonomous signal generation without the requirement for exogenous substrates or external activation. Therefore, lux-based bioluminescent bioreporters are the only truly autonomous light-generating sensors in existence. Unfortunately, the bacterial lux system has not yet been efficiently expressed in mammalian cells. In this research, three approaches for optimal expression of the a and b subunits of the bacterial luciferase protein were compared and reporter signal stability was evaluated from stably transfected human embryonic kidney cells. Maximum light levels were obtained from cells expressing the luciferase subunits linked with an internal ribosomal entry site (IRES). Cells harboring this construct produced bioluminescence equaling 2.6 X 106 photons/sec compared to 7.2 X 104 photons/sec obtained from cells expressing the luciferase from a dual promoter vector and 3.5 X 104 photons/sec from a Lux fusion protein. Furthermore, the bioluminescence levels remained stable for more than forty cell passages (5 months) in the absence of antibiotic selection. After this time, bioluminescence signals dropped at a rate of approximately 5% per cell passage. These data indicate that mammalian cell lines can be engineered to efficiently express the bacterial lux system, thus lending themselves to possible long-term continuous monitoring or imaging applications in vivo.

  17. Expression of apoptotic regulatory molecules in renal cell carcinoma: elevated expression of Fas ligand.

    PubMed

    Olive, C; Cheung, C; Nicol, D; Falk, M C

    1999-02-01

    Renal cell carcinoma (RCC) is the most common renal neoplasm. Despite being infiltrated by tumour infiltrating lymphocytes (TIL), these TIL are unable to control tumour growth in vivo, suggesting that the cytotoxic capacity of TIL against RCC is impaired, or that the tumour cells are resistant to killing and therefore escape detection by the immune system. It is postulated that the expression of apoptotic regulatory molecules in RCC favours tumour cell survival. The present study has therefore determined the expression of Fas (APO-1/CD95), Fas ligand (Fas L) and bcl-2 in these tumours. The expression of Fas, Fas L and bcl-2 mRNA transcripts was determined in RCC, normal kidney and peripheral blood by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR), following RNA extraction and cDNA synthesis from tissues and cell samples. Transcript levels were measured by densitometry after Southern blot hybridization of PCR products with internal radio-labelled oligonucleotide probes; a densitometry score was assigned to each hybridizing DNA band and expressed as a ratio of the glyceraldehyde-3-phosphate dehydrogenase content. In peripheral blood, the expression of Fas L and bcl-2 transcripts was similar between patients and normal healthy individuals; however, Fas transcript expression was significantly down-regulated in the patients' versus normal peripheral blood (P = 0.026). Most interestingly, significantly up-regulated Fas L expression was observed in RCC compared to normal kidney (P = 0.041). In contrast, bcl-2 transcripts were well represented in normal kidney but markedly decreased in RCC (P = 0.021). The expression of Fas transcripts in normal kidney and RCC was variable. These data demonstrate elevated expression of Fas L transcripts in RCC, but the functional relevance of this remains to be investigated. PMID:10101681

  18. Transcriptional Regulation of Tlr11 Gene Expression in Epithelial Cells*

    PubMed Central

    Cai, Zhenyu; Shi, Zhongcheng; Sanchez, Amir; Zhang, Tingting; Liu, Mingyao; Yang, Jianghua; Wang, Fen; Zhang, Dekai

    2009-01-01

    As sensors of invading microorganisms, Toll-like receptors (TLRs) are expressed not only on macrophages and dendritic cells (DCs) but also on epithelial cells. In the TLR family, Tlr11 appears to have the unique feature in that it is expressed primarily on epithelial cells, although it is also expressed on DCs and macrophages. Here, we demonstrate that transcription of the Tlr11 gene is regulated through two cis-acting elements, one Ets-binding site and one interferon regulatory factor (IRF)-binding site. The Ets element interacts with the epithelium-specific transcription factors, ESE-1 and ESE-3, and the IRF motif interacts with IRF-8. Thus, Tlr11 expression on epithelial cells is regulated by the transcription factors that are presumably distinct from transcription factors that regulate the expression of TLRs in innate immune cells such as macrophages and DCs. Our results imply that the distinctive transcription regulatory machinery for TLRs on epithelium may represent a promising new avenue for the development of epithelia-specific therapeutic interventions. PMID:19801549

  19. Regulation of somatic cell reprogramming through inducible mir-302 expression.

    PubMed

    Lin, Shi-Lung; Chang, Donald C; Lin, Chun-Hung; Ying, Shao-Yao; Leu, Davey; Wu, David T S

    2011-02-01

    Global demethylation is required for early zygote development to establish stem cell pluripotency, yet our findings reiterate this epigenetic reprogramming event in somatic cells through ectopic introduction of mir-302 function. Here, we report that induced mir-302 expression beyond 1.3-fold of the concentration in human embryonic stem (hES) H1 and H9 cells led to reprogramming of human hair follicle cells (hHFCs) to induced pluripotent stem (iPS) cells. This reprogramming mechanism functioned through mir-302-targeted co-suppression of four epigenetic regulators, AOF2 (also known as KDM1 or LSD1), AOF1, MECP1-p66 and MECP2. Silencing AOF2 also caused DNMT1 deficiency and further enhanced global demethylation during somatic cell reprogramming (SCR) of hHFCs. Re-supplementing AOF2 in iPS cells disrupted such global demethylation and induced cell differentiation. Given that both hES and iPS cells highly express mir-302, our findings suggest a novel link between zygotic reprogramming and SCR, providing a regulatory mechanism responsible for global demethylation in both events. As the mechanism of conventional iPS cell induction methods remains largely unknown, understanding this microRNA (miRNA)-mediated SCR mechanism may shed light on the improvements of iPS cell generation. PMID:20870751

  20. Biotransformation of dihydroisosteviol and the effects of transformed products on steroidogenic gene expressions.

    PubMed

    Chang, Shwu-Fen; Yang, Li-Ming; Huang, Tsurng-Juhn; Chen, Chin-Yang; Sheu, Shiow-Yunn; Liu, Pan-Chun; Lin, Shwu-Jiuan

    2013-11-01

    The biotransformation of dihydroisosteviol with Absidia pseudocylindrospora ATCC 24169, Streptomyces griseus ATCC 10137, Mucor recurvatus MR36, and Aspergillus niger BCRC 31130 yielded 15 metabolites, eight of which were previously unknown. Structures of metabolites were established by 2D NMR techniques and HRMS data, two of which were further corroborated by chemical means, and another via single-crystal X-ray diffraction analysis. Subsequently, two steroidogenic cell lines (Y-1 mouse adrenal tumor and MA-10 mouse Leydig tumor cells) were used in a reverse transcription-PCR analysis to assess the effects of all compounds on steroidogenic gene expressions using forskolin as a positive control. The tested gene expressions included steroidogenic factor-1 (SF-1), steroidogenic acute regulatory protein (StAR), and cytochrome P450 side-chain cleavage (P450scc) enzyme. Gene expression profiles showed that ten of the tested compounds effectively suppressed P450SCC mRNA expression in both Y-1 and MA-10 cells. Several induced SF-1 gene expression and two enhanced StAR gene expression in Y-1 cells. By contrast, in MA-10 cells, one compound effectively suppressed StAR mRNA expression, whereas for others effectively suppressed SF-1 gene expression. The results suggest that analogs of dihydroisosteviol can be potential modulators to alter steroidogenic gene expressions and subsequent enzyme activities. PMID:23948258

  1. Evaluating cell-surface expression and measuring activation of mammalian odorant receptors in heterologous cells

    PubMed Central

    Zhuang, Hanyi; Matsunami, Hiroaki

    2009-01-01

    A fundamental question in olfaction is which odorant receptors (ORs) are activated by a given odorant. A major roadblock to investigate odorant-OR relationship in mammals has been an inability to express ORs in heterologous cells suitable for screening active ligands for ORs. The discovery of the receptor-transporting protein (RTP) family has facilitated the effective cell-surface expression of ORs in heterologous cells. The establishment of a robust heterologous expression system for mammalian ORs facilitates the high-throughput “deorphanization” of these receptors by matching them to their cognate ligands. This protocol details the method used for evaluating the cell-surface expression and measuring the functional activation of ORs of transiently-expressed mammalian odorant receptors in HEK293T cells. The stages of odorant receptor cell-surface expression include cell culture preparation, transfer of cells, transfection, and immunocytochemistry/flow cytometry, odorant stimulation, and luciferase assay. This protocol can be completed in a period of 3 days from transfer of cells to cell-surface expression detection and/or measurement of functional activation. PMID:18772867

  2. c-myc protooncogene expression in mouse erythroleukemia cells.

    PubMed Central

    Lachman, H M

    1989-01-01

    Murine erythroleukemia (MEL) cells are erythroid progenitors whose programs of erythroid differentiation has been interrupted by transformation with the Friend virus complex. As a result of the ability of certain chemicals such as dimethylsulfoxide (DMSO) to induce terminal erythroid differentiation, the cells have been used as a model for understanding the molecular basis of cellular differentiation. Recent work on MEL cells as well as other differentiating systems indicates that expression of cellular protooncogenes is implicated in chemically mediated differentiation. In MEL cells the expression of the c-myc protooncogene undergoes unusual biphasic changes following inducer treatment. Levels of c-myc mRNA decrease 10- to 20-fold between 1 and 2 hr and are then reexpressed between 12 and 24 hr. These changes occur as a result of complex transcriptional and posttranscriptional regulatory events. Recent DNA transfection experiments, in which MEL cells were transfected with myc expression vectors, indicate that both the early decrease in c-myc expression and its subsequent reexpression are important events in the differentiation pathway. The work on MEL cells, as well as on other models of differentiation, is directed at understanding the molecular basis of leukemogenic transformation and cellular differentiation. The ability of c-myc, as well as other protooncogenes, to influence both of these events indicates that cellular protooncogenes play a central role in their regulation. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. PMID:2647476

  3. Expression Profiling of Single Mammalian Cells – Small is Beautiful

    PubMed Central

    2000-01-01

    Increasingly mRNA expression patterns established using a variety of molecular technologies such as cDNA microarrays, SAGE and cDNA display are being used to identify potential regulatory genes and as a means of providing valuable insights into the biological status of the starting sample. Until recently, the application of these techniques has been limited to mRNA isolated from millions or, at very best, several thousand cells thereby restricting the study of small samples and complex tissues. To overcome this limitation a variety of amplification approaches have been developed which are capable of broadly evaluating mRNA expression patterns in single cells. This review will describe approaches that have been employed to examine global gene expression patterns either in small numbers of cells or, wherever possible, in actual isolated single cells. The first half of the review will summarize the technical aspects of methods developed for single-cell analysis and the latter half of the review will describe the areas of biological research that have benefited from single-cell expression analysis. PMID:11025531

  4. Sp3 regulates fas expression in lung epithelial cells.

    PubMed Central

    Pang, H; Miranda, K; Fine, A

    1998-01-01

    By transducing an apoptotic signal in immune effector cells, Fas has been directly implicated in the control of immunological activity. Expression and functional results, however, have also suggested a role for Fas in regulating cell turnover in specific epithelial populations. To characterize factors responsible for Fas expression in epithelial cells, approximately 3 kb of the 5' flanking region of the mouse Fas gene was isolated. By rapid amplification of cDNA ends and primer extension, transcriptional start sites were identified within 50 bp upstream of the translation start site. Transient transfection of promoter-luciferase constructs in a mouse lung epithelial cell line, MLE-15, localized promoter activity to the first 77 bp of upstream sequence. By using a 60 bp DNA probe (-18 to -77) in electrophoretic mobility-shift assays, three shifted complexes were found. Incubation with excess cold Sp1 oligonucleotide or an anti-Sp3 antibody inhibited complex formation. Site-directed mutagenesis of the Sp1 site resulted in 60-70% loss of promoter activity. In Drosophila SL-2 cells, promoter activity was markedly increased by co-transfection of an Sp3 expression construct. These results show that the Sp3 protein is involved in regulating Fas gene expression in lung epithelial cells. PMID:9639581

  5. Selective deletion of Smad4 in postnatal germ cells does not affect spermatogenesis or fertility in mice.

    PubMed

    Hao, Xiao-Xia; Chen, Su-Ren; Tang, Ji-Xin; Li, Jian; Cheng, Jin-Mei; Jin, Cheng; Wang, Xiu-Xia; Liu, Yi-Xun

    2016-07-01

    SMAD4 is the central component of canonical signaling in the transforming growth factor beta (TGFβ) superfamily. Loss of Smad4 in Sertoli cells affects the expansion of the fetal testis cords, whereas selective deletion of Smad4 in Leydig cells alone does not appreciably alter fetal or adult testis development. Loss of Smad4 in Sertoli and Leydig cells, on the other hand, leads to testicular dysgenesis, and tumor formation in mice. Within the murine testes, Smad4 is also expressed in germ cells of the seminiferous tubules. We therefore, crossed Ngn3-Cre or Stra8-Cre transgenic mice with Smad4-flox mice to generate conditional knockout animals in which Smad4 was specifically deleted in postnatal germ cells to further uncover cell type-specific requirement of Smad4. Unexpectedly, these germ-cell-knockout mice were fertile and did not exhibit any detectable abnormalities in spermatogenesis, indicating that Smad4 is not required for the production of sperm; instead, these data indicate a cell type-specific requirement of Smad4 primarily during testis development. Mol. Reprod. Dev. 83: 615-623, 2016. © 2016 Wiley Periodicals, Inc. PMID:27265621

  6. SNAP25 Expression in Mammalian Retinal Horizontal Cells

    PubMed Central

    Hirano, Arlene A.; Brandstätter, Johann Helmut; Morgans, Catherine W.; Brecha, Nicholas C.

    2014-01-01

    Horizontal cells mediate inhibitory feedforward and feedback lateral interactions in the outer retina at photoreceptor terminals and bipolar cell dendrites; however, the mechanisms that underlie synaptic transmission from mammalian horizontal cells are poorly understood. The localization of a vesicular γ-aminobutyric acid (GABA) transporter (VGAT) to horizontal cell processes in primate and rodent retinae suggested that mammalian horizontal cells release transmitter in a vesicular manner. Toward determining whether the molecular machinery for vesicular transmitter release is present in horizontal cells, we investigated the expression of SNAP25 (synaptosomal-associated protein of 25 kDa), a key SNARE protein, by immunocytochemistry with cell type-specific markers in the retinae of mouse, rat, rabbit, and monkey. Different commercial antibodies to SNAP25 were tested on vertical sections of retina. We report the robust expression of SNAP25 in both plexiform layers. Double labeling with SNAP25 and calbindin antibodies demonstrated that horizontal cell processes and their endings in photoreceptor triad synapses were strongly labeled for both proteins in mouse, rat, rabbit, and monkey retinae. Double labeling with parvalbumin antibodies in monkey retina verified SNAP25 immunoreactivity in all horizontal cells. Pre-embedding immunoelectron microscopy in rabbit retina confirmed expression of SNAP25 in lateral elements within photoreceptor triad synapses. The SNAP25 immunoreactivity in the plexiform layers and outer nuclear layer fell into at least three patterns depending on the antibody, suggesting a differential distribution of SNAP25 isoforms. The presence of SNAP25a and SNAP25b isoforms in mouse retina was established by reverse transcriptase-polymerase chain reaction. SNAP25 expression in mammalian horizontal cells along with other SNARE proteins is consistent with vesicular exocytosis. PMID:21280047

  7. Regulation of cell-to-cell variability in divergent gene expression

    NASA Astrophysics Data System (ADS)

    Yan, Chao; Wu, Shuyang; Pocetti, Christopher; Bai, Lu

    2016-03-01

    Cell-to-cell variability (noise) is an important feature of gene expression that impacts cell fitness and development. The regulatory mechanism of this variability is not fully understood. Here we investigate the effect on gene expression noise in divergent gene pairs (DGPs). We generated reporters driven by divergent promoters, rearranged their gene order, and probed their expressions using time-lapse fluorescence microscopy and single-molecule fluorescence in situ hybridization (smFISH). We show that two genes in a co-regulated DGP have higher expression covariance compared with the separate, tandem and convergent configurations, and this higher covariance is caused by more synchronized firing of the divergent transcriptions. For differentially regulated DGPs, the regulatory signal of one gene can stochastically `leak' to the other, causing increased gene expression noise. We propose that the DGPs' function in limiting or promoting gene expression noise may enhance or compromise cell fitness, providing an explanation for the conservation pattern of DGPs.

  8. Relation of CD30 expression to survival and morphology in large cell B cell lymphomas.

    PubMed Central

    Noorduyn, L A; de Bruin, P C; van Heerde, P; van de Sandt, M M; Ossenkoppele, G J; Meijer, C J

    1994-01-01

    AIMS--To investigate whether CD30 expression is correlated with anaplastic morphology, and whether this correlated with a better survival in large cell B cell lymphomas, as has been described for T cell lymphomas. METHODS--CD30 expression was investigated using frozen sections in a series of 146 large cell B cell lymphomas. Clinical data and follow up information were collected from 25 lymphomas with strong CD30 expression, 30 lymphomas with partial CD30 expression, and a control group of 25 lymphomas which did not express CD30. RESULTS--Morphological distinction between anaplastic and non-anaplastic tumours was difficult. Of the cases with an anaplastic morphology, 50% were CD30 positive, as were 24% of the polymorphic centroblastic B cell lymphomas. Only 65% of the morphologically non-anaplastic tumours were completely CD30 negative. There was no difference in survival among patients with lymphomas expressing CD30 and those that did not. Patients with morphologically anaplastic B cell lymphomas did not differ in their survivals from those with other high grade B cell lymphomas. Clinical stage at presentation was the only variable that was significantly associated with survival. CONCLUSIONS--CD30 expression occurs frequently in large cell B cell lymphomas and is poorly related to anaplastic morphology. Morphological distinction between anaplastic and non-anaplastic tumours is difficult. In contrast to T cell lymphomas, CD30 positive B cell lymphomas do not show a relatively favourable clinical course. The results presented here raise serious doubts as to whether large cell B cell lymphoma, based on the expression of CD30 or anaplastic morphology, can really be termed a separate entity. Images PMID:8132806

  9. Targeting telomerase-expressing cancer cells

    PubMed Central

    Ouellette, Michel M; Wright, Woodring E; Shay, Jerry W

    2011-01-01

    Abstract The role of telomeres and telomerase as a target for cancer therapeutics is an area of continuing interest. This review is intended to provide an update on the field, pointing to areas in which our knowledge remains deficient and exploring the details of the most promising areas being advanced into clinical trials. Topics that will be covered include the role of dysfunctional telomeres in cellular aging and how replicative senescence provides an initial barrier to the emergence of immortalized cells, a hallmark of cancer. As an important translational theme, this review will consider possibilities for selectively targeting telomeres and telomerase to enhance cancer therapy. The role of telomerase as an immunotherapy, as a gene therapy approach using telomerase promoter driven oncolytic viruses and as a small oligonucleotide targeted therapy (Imetelstat) will be discussed. PMID:21332640

  10. Targeting telomerase-expressing cancer cells.

    PubMed

    Ouellette, Michel M; Wright, Woodring E; Shay, Jerry W

    2011-07-01

    The role of telomeres and telomerase as a target for cancer therapeutics is an area of continuing interest. This review is intended to provide an update on the field, pointing to areas in which our knowledge remains deficient and exploring the details of the most promising areas being advanced into clinical trials. Topics that will be covered include the role of dysfunctional telomeres in cellular aging and how replicative senescence provides an initial barrier to the emergence of immortalized cells, a hallmark of cancer. As an important translational theme, this review will consider possibilities for selectively targeting telomeres and telomerase to enhance cancer therapy. The role of telomerase as an immunotherapy, as a gene therapy approach using telomerase promoter driven oncolytic viruses and as a small oligonucleotide targeted therapy (Imetelstat) will be discussed. PMID:21332640

  11. Human Neural Cells Transiently Express Reelin during Olfactory Placode Development

    PubMed Central

    Antal, M. Cristina; Samama, Brigitte; Ghandour, M. Said; Boehm, Nelly

    2015-01-01

    Reelin, an extracellular glycoprotein is essential for migration and correct positioning of neurons during development. Since the olfactory system is known as a source of various migrating neuronal cells, we studied Reelin expression in the two chemosensory olfactory systems, main and accessory, during early developmental stages of human foetuses/embryos from Carnegie Stage (CS) 15 to gestational week (GW) 14. From CS 15 to CS 18, but not at later stages, a transient expression of Reelin was detected first in the presumptive olfactory and then in the presumptive vomeronasal epithelium. During the same period, Reelin-positive cells detach from the olfactory/vomeronasal epithelium and migrate through the mesenchyme beneath the telencephalon. Dab 1, an adaptor protein of the Reelin pathway, was simultaneously expressed in the migratory mass from CS16 to CS17 and, at later stages, in the presumptive olfactory ensheathing cells. Possible involvements of Reelin and Dab 1 in the peripheral migrating stream are discussed. PMID:26270645

  12. Protein expression analyses at the single cell level.

    PubMed

    Ohno, Masae; Karagiannis, Peter; Taniguchi, Yuichi

    2014-01-01

    The central dogma of molecular biology explains how genetic information is converted into its end product, proteins, which are responsible for the phenotypic state of the cell. Along with the protein type, the phenotypic state depends on the protein copy number. Therefore, quantification of the protein expression in a single cell is critical for quantitative characterization of the phenotypic states. Protein expression is typically a dynamic and stochastic phenomenon that cannot be well described by standard experimental methods. As an alternative, fluorescence imaging is being explored for the study of protein expression, because of its high sensitivity and high throughput. Here we review key recent progresses in fluorescence imaging-based methods and discuss their application to proteome analysis at the single cell level. PMID:25197931

  13. Human Neural Cells Transiently Express Reelin during Olfactory Placode Development.

    PubMed

    Antal, M Cristina; Samama, Brigitte; Ghandour, M Said; Boehm, Nelly

    2015-01-01

    Reelin, an extracellular glycoprotein is essential for migration and correct positioning of neurons during development. Since the olfactory system is known as a source of various migrating neuronal cells, we studied Reelin expression in the two chemosensory olfactory systems, main and accessory, during early developmental stages of human foetuses/embryos from Carnegie Stage (CS) 15 to gestational week (GW) 14. From CS 15 to CS 18, but not at later stages, a transient expression of Reelin was detected first in the presumptive olfactory and then in the presumptive vomeronasal epithelium. During the same period, Reelin-positive cells detach from the olfactory/vomeronasal epithelium and migrate through the mesenchyme beneath the telencephalon. Dab 1, an adaptor protein of the Reelin pathway, was simultaneously expressed in the migratory mass from CS16 to CS17 and, at later stages, in the presumptive olfactory ensheathing cells. Possible involvements of Reelin and Dab 1 in the peripheral migrating stream are discussed. PMID:26270645

  14. Spexin Expression in Normal Rat Tissues

    PubMed Central

    Porzionato, Andrea; Rucinski, Marcin; Macchi, Veronica; Stecco, Carla; Malendowicz, Ludwik K.; De Caro, Raffaele

    2010-01-01

    Spexin is a highly conserved peptide which was recently identified through the bioinformatics approach. Immunohistochemical analysis of its expression has not yet been performed. Thus, in this study, we examined spexin location in a wide range of rat organs by both RT-PCR and IHC. RT-PCR identified spexin mRNA in all tissues examined. Spexin immunoreaction was mainly cytoplasmic. Spexin was immunohistochemically detected, although with different staining intensities, in epithelia and glands of skin and respiratory, digestive, urinary, and reproductive systems. Smooth muscle cells showed weak immunostaining, and connective tissue was negative. In the central nervous system, neuronal groups showed different intensities for reaction product. Immunoreaction was also found in ganglionic cells of both trigeminal and superior cervical ganglia and in photoreceptor, inner nuclear, and ganglionic layers of the retina. In the endocrine system, spexin immunoreaction was detected in the hypothalamic paraventricular and supraoptic nuclei; adenohypophysis, thyroid, and parathyroid glands; adrenal cortex and medulla (mainly ganglionic cells); Leydig cells; and thecal, luteal, and interstitial cells of the ovary. Because of its widespread expression, spexin is probably involved in many different physiological functions; in particular, location of spexin in neurons and endocrine cells suggests its roles as neurotransmitter/neuromodulator and endocrine factor. (J Histochem Cytochem 58:825–837, 2010) PMID:20530460

  15. Spexin expression in normal rat tissues.

    PubMed

    Porzionato, Andrea; Rucinski, Marcin; Macchi, Veronica; Stecco, Carla; Malendowicz, Ludwik K; De Caro, Raffaele

    2010-09-01

    Spexin is a highly conserved peptide which was recently identified through the bioinformatics approach. Immunohistochemical analysis of its expression has not yet been performed. Thus, in this study, we examined spexin location in a wide range of rat organs by both RT-PCR and IHC. RT-PCR identified spexin mRNA in all tissues examined. Spexin immunoreaction was mainly cytoplasmic. Spexin was immunohistochemically detected, although with different staining intensities, in epithelia and glands of skin and respiratory, digestive, urinary, and reproductive systems. Smooth muscle cells showed weak immunostaining, and connective tissue was negative. In the central nervous system, neuronal groups showed different intensities for reaction product. Immunoreaction was also found in ganglionic cells of both trigeminal and superior cervical ganglia and in photoreceptor, inner nuclear, and ganglionic layers of the retina. In the endocrine system, spexin immunoreaction was detected in the hypothalamic paraventricular and supraoptic nuclei; adenohypophysis, thyroid, and parathyroid glands; adrenal cortex and medulla (mainly ganglionic cells); Leydig cells; and thecal, luteal, and interstitial cells of the ovary. Because of its widespread expression, spexin is probably involved in many different physiological functions; in particular, location of spexin in neurons and endocrine cells suggests its roles as neurotransmitter/neuromodulator and endocrine factor. PMID:20530460

  16. Regulation of gene expression in ovarian cancer cells by luteinizing hormone receptor expression and activation

    PubMed Central

    2011-01-01

    Background Since a substantial percentage of ovarian cancers express gonadotropin receptors and are responsive to the relatively high concentrations of pituitary gonadotropins during the postmenopausal years, it has been suggested that receptor activation may contribute to the etiology and/or progression of the neoplasm. The goal of the present study was to develop a cell model to determine the impact of luteinizing hormone (LH) receptor (LHR) expression and LH-mediated LHR activation on gene expression and thus obtain insights into the mechanism of gonadotropin action on ovarian surface epithelial (OSE) carcinoma cells. Methods The human ovarian cancer cell line, SKOV-3, was stably transfected to express functional LHR and incubated with LH for various periods of time (0-20 hours). Transcriptomic profiling was performed on these cells to identify LHR expression/activation-dependent changes in gene expression levels and pathways by microarray and qRT-PCR analyses. Results Through comparative analysis on the LHR-transfected SKOV-3 cells exposed to LH, we observed the differential expression of 1,783 genes in response to LH treatment, among which five significant families were enriched, including those of growth factors, translation regulators, transporters, G-protein coupled receptors, and ligand-dependent nuclear receptors. The most highly induced early and intermediate responses were found to occupy a network impacting transcriptional regulation, cell growth, apoptosis, and multiple signaling transductions, giving indications of LH-induced apoptosis and cell growth inhibition through the significant changes in, for example, tumor necrosis factor, Jun and many others, supportive of the observed cell growth reduction in in vitro assays. However, other observations, e.g. the substantial up-regulation of the genes encoding the endothelin-1 subtype A receptor, stromal cell-derived factor 1, and insulin-like growth factor II, all of which are potential therapeutic

  17. Tolerance Associated Gene Expression following Allogeneic Hematopoietic Cell Transplantation

    PubMed Central

    Pidala, Joseph; Bloom, Gregory C.; Eschrich, Steven; Sarwal, Minnie; Enkemann, Steve; Betts, Brian C.; Beato, Francisca; Yoder, Sean; Anasetti, Claudio

    2015-01-01

    Biologic markers of immune tolerance may facilitate tailoring of immune suppression duration after allogeneic hematopoietic cell transplantation (HCT). In a cross-sectional study, peripheral blood samples were obtained from tolerant (n = 15, median 38.5 months post-HCT) and non-tolerant (n = 17, median 39.5 post-HCT) HCT recipients and healthy control subjects (n = 10) for analysis of immune cell subsets and differential gene expression. There were no significant differences in immune subsets across groups. We identified 281 probe sets unique to the tolerant (TOL) group and 122 for non-tolerant (non-TOL). These were enriched for process networks including NK cell cytotoxicity, antigen presentation, lymphocyte proliferation, and cell cycle and apoptosis. Differential gene expression was enriched for CD56, CD66, and CD14 human lineage-specific gene expression. Differential expression of 20 probe sets between groups was sufficient to develop a classifier with > 90% accuracy, correctly classifying 14/15 TOL cases and 15/17 non-TOL cases. These data suggest that differential gene expression can be utilized to accurately classify tolerant patients following HCT. Prospective investigation of immune tolerance biologic markers is warranted. PMID:25774806

  18. Conserved Expression Signatures between Medaka and Human Pigment Cell Tumors

    PubMed Central

    Schartl, Manfred; Kneitz, Susanne; Wilde, Brigitta; Wagner, Toni; Henkel, Christiaan V.; Spaink, Herman P.; Meierjohann, Svenja

    2012-01-01

    Aberrations in gene expression are a hallmark of cancer cells. Differential tumor-specific transcript levels of single genes or whole sets of genes may be critical for the neoplastic phenotype and important for therapeutic considerations or useful as biomarkers. As an approach to filter out such relevant expression differences from the plethora of changes noted in global expression profiling studies, we searched for changes of gene expression levels that are conserved. Transcriptomes from massive parallel sequencing of different types of melanoma from medaka were generated and compared to microarray datasets from zebrafish and human melanoma. This revealed molecular conservation at various levels between fish models and human tumors providing a useful strategy for identifying expression signatures strongly associated with disease phenotypes and uncovering new melanoma molecules. PMID:22693581

  19. Reproductive fitness advantage of BCR-ABL expressing leukemia cells.

    PubMed

    Traulsen, Arne; Pacheco, Jorge M; Dingli, David

    2010-08-01

    Mutations in oncogenes and tumor suppressor genes confer a fitness advantage to cells that can lead to cancer. The tumor phenotype normally results from the interaction of many mutant genes making it difficult to estimate the fitness advantage provided by any oncogene, except when tumors depend on one oncogene only. We utilize a model of chronic myeloid leukemia (CML), to quantitate the fitness advantage conferred by expression of BCR-ABL in hematopoietic cells from in vivo patient data. We show that BCR-ABL expression provides a high fitness advantage, which explains why this single mutation drives the chronic phase of CML. PMID:20153920

  20. Do CD8 effector cells need IL-7R expression to become resting memory cells?

    PubMed

    Buentke, Eva; Mathiot, Anne; Tolaini, Mauro; Di Santo, James; Zamoyska, Rose; Seddon, Benedict

    2006-09-15

    The role for IL-7R expression in the differentiation of effector T cells into resting memory remains controversial. Here, using a conditional IL-7R transgenic model, we were able to test directly whether CD8 effector T cells require IL-7R expression for their differentiation into resting memory cells. In the absence of IL-7R expression, effector cells transferred into "full" hosts underwent a protracted and unremitting contraction compared with IL-7R-expressing control cells and were unable to develop into long-term resting memory cells. Surprisingly, when the same effector cells were transferred into empty T-cell-deficient hosts, they could generate long-lived fully functional resting memory cells independently of IL-7R expression. Formation of these latter cells was found to be dependent on IL-15, because the same IL-7R-deficient effector cells were rapidly lost from IL-15-deficient hosts, having a half-life of less than 40 hours. Therefore, our data suggest that, under physiological conditions, both IL-7 and IL-15 synergize to promote the formation of memory cells directly by limiting the contraction of effectors that occurs following an immune response and that reexpression of IL-7R is a key checkpoint in the regulation of this process. PMID:16705084

  1. Expression of gamma-glutamyl transpeptidase protects ramos B cells from oxidation-induced cell death.

    PubMed

    Karp, D R; Shimooku, K; Lipsky, P E

    2001-02-01

    The ectoenzyme, gamma-glutamyl transpeptidase (GGT, EC ) cleaves glutathione (GSH) to facilitate the recapture of cysteine for synthesis of intracellular GSH. The impact of GGT expression on cell survival during oxidative stress was investigated using the human B cell lymphoblastoid cell line, Ramos. Ramos cells did not express surface GGT and exhibited no GGT enzyme activity. In contrast, Ramos cells stably transfected with the human GGT cDNA expressed high levels of surface GGT and enzymatic activity. GGT-transfected Ramos cells were protected from apoptosis when cultured in cyst(e)ine-deficient medium. The GGT-expressing cells also had lower levels of intracellular reactive oxygen species (ROS). Homocysteic acid and alanine, inhibitors of cystine and cysteine uptake, respectively, caused increased ROS content and diminished viability of GGT expressing cells. Exogenous GSH increased the viability of the GGT-transfected cells more effectively than that of control cells, whereas the products of GSH metabolism prevented death of both the control and GGT-transfected cells comparably. These data indicate that GGT cleavage of GSH and the subsequent recapture of cysteine and cystine allow cells to maintain low levels of cellular ROS and thereby avoid apoptosis induced by oxidative stress. PMID:11080500

  2. Cell-by-Cell Dissection of Gene Expression and Chromosomal Interactions Reveals Consequences of Nuclear Reorganization

    PubMed Central

    2005-01-01

    The functional consequences of long-range nuclear reorganization were studied in a cell-by-cell analysis of gene expression and long-range chromosomal interactions in the Drosophila eye and eye imaginal disk. Position-effect variegation was used to stochastically perturb gene expression and probe nuclear reorganization. Variegating genes on rearrangements of Chromosomes X, 2, and 3 were probed for long-range interactions with heterochromatin. Studies were conducted only in tissues known to express the variegating genes. Nuclear structure was revealed by fluorescence in situ hybridization with probes to the variegating gene and heterochromatin. Gene expression was determined alternately by immunofluorescence against specific proteins and by eye pigment autofluorescence. This allowed cell-by-cell comparisons of nuclear architecture between cells in which the variegating gene was either expressed or silenced. Very strong correlations between heterochromatic association and silencing were found. Expressing cells showed a broad distribution of distances between variegating genes and their own centromeric heterochromatin, while silenced cells showed a very tight distribution centered around very short distances, consistent with interaction between the silenced genes and heterochromatin. Spatial and temporal analysis of interactions with heterochromatin indicated that variegating genes primarily associate with heterochromatin in cells that have exited the cell cycle. Differentiation was not a requirement for association, and no differences in association were observed between cell types. Thus, long-range interactions between distal chromosome regions and their own heterochromatin have functional consequences for the organism. PMID:15737020

  3. From single-cell to cell-pool transcriptomes: stochasticity in gene expression and RNA splicing.

    PubMed

    Marinov, Georgi K; Williams, Brian A; McCue, Ken; Schroth, Gary P; Gertz, Jason; Myers, Richard M; Wold, Barbara J

    2014-03-01

    Single-cell RNA-seq mammalian transcriptome studies are at an early stage in uncovering cell-to-cell variation in gene expression, transcript processing and editing, and regulatory module activity. Despite great progress recently, substantial challenges remain, including discriminating biological variation from technical noise. Here we apply the SMART-seq single-cell RNA-seq protocol to study the reference lymphoblastoid cell line GM12878. By using spike-in quantification standards, we estimate the absolute number of RNA molecules per cell for each gene and find significant variation in total mRNA content: between 50,000 and 300,000 transcripts per cell. We directly measure technical stochasticity by a pool/split design and find that there are significant differences in expression between individual cells, over and above technical variation. Specific gene coexpression modules were preferentially expressed in subsets of individual cells, including one enriched for mRNA processing and splicing factors. We assess cell-to-cell variation in alternative splicing and allelic bias and report evidence of significant differences in splice site usage that exceed splice variation in the pool/split comparison. Finally, we show that transcriptomes from small pools of 30-100 cells approach the information content and reproducibility of contemporary RNA-seq from large amounts of input material. Together, our results define an experimental and computational path forward for analyzing gene expression in rare cell types and cell states. PMID:24299736

  4. Neuropilin 1 expression correlates with differentiation status of epidermal cells and cutaneous squamous cell carcinomas.

    PubMed

    Shahrabi-Farahani, Shokoufeh; Wang, Lili; Zwaans, Bernadette M M; Santana, Jeans M; Shimizu, Akio; Takashima, Seiji; Kreuter, Michael; Coultas, Leigh; D'Amore, Patricia A; Arbeit, Jeffrey M; Akslen, Lars A; Bielenberg, Diane R

    2014-07-01

    Neuropilins (NRPs) are cell surface receptors for vascular endothelial growth factor (VEGF) and SEMA3 (class 3 semaphorin) family members. The role of NRPs in neurons and endothelial cells has been investigated, but the expression and role of NRPs in epithelial cells is much less clear. Herein, the expression and localization of NRP1 was investigated in human and mouse skin and squamous cell carcinomas (SCCs). Results indicated that NRP1 mRNA and protein was expressed in the suprabasal epithelial layers of the skin sections. NRP1 staining did not overlap with that of keratin 14 (K14) or proliferating cell nuclear antigen, but did co-localize with staining for keratin 1, indicating that differentiated keratinocytes express NRP1. Similar to the expression of NRP1, VEGF-A was expressed in suprabasal epithelial cells, whereas Nrp2 and VEGFR2 were not detectable in the epidermis. The expression of NRP1 correlated with a high degree of differentiation in human SCC specimens, human SCC xenografts, and mouse K14-HPV16 transgenic SCC. UVB irradiation of mouse skin induced Nrp1 upregulation. In vitro, Nrp1 was upregulated in primary keratinocytes in response to differentiating media or epidermal growth factor-family growth factors. In conclusion, the expression of NRP1 is regulated in the skin and is selectively produced in differentiated epithelial cells. NRP1 may function as a reservoir to sequester VEGF ligand within the epithelial compartment, thereby modulating its bioactivity. PMID:24791743

  5. Polyclonal T-Cells Express CD1a in Langerhans Cell Histiocytosis (LCH) Lesions

    PubMed Central

    West, Jennifer A.; Olsen, Sharon L.; Mitchell, Jenée M.; Priddle, Ross E.; Luke, Jennifer M.; Åkefeldt, Selma Olsson; Henter, Jan-Inge; Turville, Christopher; Kannourakis, George

    2014-01-01

    Langerhans cell histiocytosis (LCH) is a complex and poorly understood disorder that has characteristics of both inflammatory and neoplastic disease. By using eight-colour flow cytometry, we have identified a previously unreported population of CD1a+/CD3+ T-cells in LCH lesions. The expression of CD1a is regarded as a hallmark of this disease; however, it has always been presumed that it was only expressed by pathogenic Langerhans cells (LCs). We have now detected CD1a expression by a range of T-cell subsets within all of the LCH lesions that were examined, establishing that CD1a expression in these lesions is no longer restricted to pathogenic LCs. The presence of CD1a+ T-cells in all of the LCH lesions that we have studied to date warrants further investigation into their biological function to determine whether these cells are important in the pathogenesis of LCH. PMID:25343480

  6. Single-cell PCR profiling of gene expression in hematopoiesis.

    PubMed

    Teles, José; Enver, Tariq; Pina, Cristina

    2014-01-01

    Single-cell analysis of gene expression offers the possibility of exploring cellular and molecular heterogeneity in stem and developmental cell systems, including cancer, to infer routes of cellular specification and their respective gene regulatory modules. PCR-based technologies, although limited to the analysis of a predefined set of genes, afford a cost-effective balance of throughput and biological information and have become a method of choice in stem cell laboratories. Here we describe an experimental and analytical protocol based on the Fluidigm microfluidics platform for the simultaneous expression analysis of 48 or 96 genes in multiples of 48 or 96 cells. We detail wet laboratory procedures and describe clustering, principal component analysis, correlation, and classification tools for the inference of cellular pathways and gene networks. PMID:25062620

  7. Spatial reconstruction of single-cell gene expression

    PubMed Central

    Satija, Rahul; Farrell, Jeffrey A.; Gennert, David; Schier, Alexander F.; Regev, Aviv

    2015-01-01

    Spatial localization is a key determinant of cellular fate and behavior, but spatial RNA assays traditionally rely on staining for a limited number of RNA species. In contrast, single-cell RNA-seq allows for deep profiling of cellular gene expression, but established methods separate cells from their native spatial context. Here we present Seurat, a computational strategy to infer cellular localization by integrating single-cell RNA-seq data with in situ RNA patterns. We applied Seurat to spatially map 851 single cells from dissociated zebrafish (Danio rerio) embryos, inferring a transcriptome-wide map of spatial patterning. We confirmed Seurat’s accuracy using several experimental approaches, and used it to identify a set of archetypal expression patterns and spatial markers. Additionally, Seurat correctly localizes rare subpopulations, accurately mapping both spatially restricted and scattered groups. Seurat will be applicable to mapping cellular localization within complex patterned tissues in diverse systems. PMID:25867923

  8. Syndecan-4-expressing muscle progenitor cells in the SP engraft as satellite cells during muscle regeneration.

    PubMed

    Tanaka, Kathleen Kelly; Hall, John K; Troy, Andrew A; Cornelison, D D W; Majka, Susan M; Olwin, Bradley B

    2009-03-01

    Skeletal muscle satellite cells, located between the basal lamina and plasma membrane of myofibers, are required for skeletal muscle regeneration. The capacity of satellite cells as well as other cell lineages including mesoangioblasts, mesenchymal stem cells, and side population (SP) cells to contribute to muscle regeneration has complicated the identification of a satellite stem cell. We have characterized a rare subset of the muscle SP that efficiently engrafts into the host satellite cell niche when transplanted into regenerating muscle, providing 75% of the satellite cell population and 30% of the myonuclear population, respectively. These cells are found in the satellite cell position, adhere to isolated myofibers, and spontaneously undergo myogenesis in culture. We propose that this subset of SP cells (satellite-SP cells), characterized by ABCG2, Syndecan-4, and Pax7 expression, constitutes a self-renewing muscle stem cell capable of generating both satellite cells and their myonuclear progeny in vivo. PMID:19265661

  9. Immunohistological recognition of cyclin D1 expression by non-lymphoid cells among lymphoid neoplastic cells.

    PubMed

    Abdulla, Zainalabideen; Turley, Helen; Gatter, Kevin; Pezzella, Francesco

    2014-03-01

    Cyclin D1 immunostaining of non-neoplastic cells has been a source of diagnostic confusion especially in lymphoproliferative lesions. This study has reviewed these in two hundred and thirty-one haematopathological samples stained for cyclin D1. Most cases were formalin-fixed except for a few bone marrow trephines, which were B-5 fixed, and EDTA decalcified. Overall, 94% (216/231) of cases showed one or more types of non-neoplastic cells expressing Cyclin D1 of variable intensity. Endothelial cells and histiocytes were the most commonly identified Cyclin D1 positive cells being positive in 92% (214/231) of cases. Other normal cell types identified included fat cells, stromal fibroblasts, glial cells, spermatocytes, smooth muscle cells, osteoblasts and where present epithelial cells. Many normal cell types can express cyclinD1. Knowledge of these is useful to prevent misinterpretation of cyclin D1 positive tumours. PMID:23758159

  10. Robust enumeration of cell subsets from tissue expression profiles

    PubMed Central

    Newman, Aaron M.; Liu, Chih Long; Green, Michael R.; Gentles, Andrew J.; Feng, Weiguo; Xu, Yue; Hoang, Chuong D.; Diehn, Maximilian; Alizadeh, Ash A.

    2015-01-01

    We introduce CIBERSORT, a method for characterizing cell composition of complex tissues from their gene expression profiles. When applied to enumeration of hematopoietic subsets in RNA mixtures from fresh, frozen, and fixed tissues, including solid tumors, CIBERSORT outperformed other methods with respect to noise, unknown mixture content, and closely related cell types. CIBERSORT should enable large-scale analysis of RNA mixtures for cellular biomarkers and therapeutic targets (http://cibersort.stanford.edu). PMID:25822800

  11. Improved expression systems for regulated expression in Salmonella infecting eukaryotic cells.

    PubMed

    Medina, Carlos; Camacho, Eva María; Flores, Amando; Mesa-Pereira, Beatriz; Santero, Eduardo

    2011-01-01

    In this work we describe a series of improvements to the Salmonella-based salicylate-inducible cascade expression system comprised of a plasmid-borne expression module, where target gene expression is driven by the P(m) promoter governed by the XylS2 regulator, and a genome-integrated regulatory module controlled by the nahR/P(sal) system. We have constructed a set of high and low-copy number plasmids bearing modified versions of the expression module with a more versatile multiple cloning site and different combinations of the following elements: (i) the nasF transcriptional attenuator, which reduces basal expression levels, (ii) a strong ribosome binding site, and (iii) the Type III Secretion System (TTSS) signal peptide from the effector protein SspH2 to deliver proteins directly to the eukaryotic cytosol following bacterial infection of animal cells. We show that different expression module versions can be used to direct a broad range of protein production levels. Furthermore, we demonstrate that the efficient reduction of basal expression by the nasF attenuator allows the cloning of genes encoding highly cytotoxic proteins such as colicin E3 even in the absence of its immunity protein. Additionally, we show that the Salmonella TTSS is able to translocate most of the protein produced by this regulatory cascade to the cytoplasm of infected HeLa cells. Our results indicate that these vectors represent useful tools for the regulated overproduction of heterologous proteins in bacterial culture or in animal cells, for the cloning and expression of genes encoding toxic proteins and for pathogenesis studies. PMID:21829692

  12. Improved Expression Systems for Regulated Expression in Salmonella Infecting Eukaryotic Cells

    PubMed Central

    Medina, Carlos; Camacho, Eva María; Flores, Amando; Mesa-Pereira, Beatriz; Santero, Eduardo

    2011-01-01

    In this work we describe a series of improvements to the Salmonella-based salicylate-inducible cascade expression system comprised of a plasmid-borne expression module, where target gene expression is driven by the Pm promoter governed by the XylS2 regulator, and a genome-integrated regulatory module controlled by the nahR/Psal system. We have constructed a set of high and low-copy number plasmids bearing modified versions of the expression module with a more versatile multiple cloning site and different combinations of the following elements: (i) the nasF transcriptional attenuator, which reduces basal expression levels, (ii) a strong ribosome binding site, and (iii) the Type III Secretion System (TTSS) signal peptide from the effector protein SspH2 to deliver proteins directly to the eukaryotic cytosol following bacterial infection of animal cells. We show that different expression module versions can be used to direct a broad range of protein production levels. Furthermore, we demonstrate that the efficient reduction of basal expression by the nasF attenuator allows the cloning of genes encoding highly cytotoxic proteins such as colicin E3 even in the absence of its immunity protein. Additionally, we show that the Salmonella TTSS is able to translocate most of the protein produced by this regulatory cascade to the cytoplasm of infected HeLa cells. Our results indicate that these vectors represent useful tools for the regulated overproduction of heterologous proteins in bacterial culture or in animal cells, for the cloning and expression of genes encoding toxic proteins and for pathogenesis studies. PMID:21829692

  13. Global gene expression response to telomerase in bovine adrenocortical cells

    SciTech Connect

    Perrault, Steven D.; Hornsby, Peter J.; Betts, Dean H. . E-mail: bettsd@uoguelph.ca

    2005-09-30

    The infinite proliferative capability of most immortalized cells is dependent upon the presence of the enzyme telomerase and its ability to maintain telomere length and structure. However, telomerase may be involved in a greater system than telomere length regulation, as recent evidence has shown it capable of increasing wound healing in vivo, and improving cellular proliferation rate and survival from apoptosis in vitro. Here, we describe the global gene expression response to ectopic telomerase expression in an in vitro bovine adrenocortical cell model. Telomerase-immortalized cells showed an increased ability for proliferation and survival in minimal essential medium above cells transgenic for GFP. cDNA microarray analyses revealed an altered cell state indicative of increased adrenocortical cell proliferation regulated by the IGF2 pathway and alterations in members of the TGF-B family. As well, we identified alterations in genes associated with development and wound healing that support a model that high telomerase expression induces a highly adaptable, progenitor-like state.

  14. Ikaros expression sensitizes leukemic cells to the chemotherapeutic drug doxorubicin

    PubMed Central

    He, Licai; Gao, Shenmeng; Zhu, Zhenfeng; Chen, Shang; Gu, Haihua

    2016-01-01

    Ikaros is an important transcription factor involved in the development and differentiation of hematopoietic cells. However, its role in the treatment of hematopoietic malignancies such as leukemia is less well understood. In the present study, it was observed by data mining of the Oncomine database that high expression levels of full-length Ikaros (IK1) is correlated with increased sensitivity of cancer cells to treatments with chemotherapeutic drugs, including doxorubicin (DOX). To examine the functional significance of this observation, the expression of IK1 in a leukemia cell line was altered, and the response of leukemic cells to DOX treatment was analyzed. It was observed that overexpression of IK1 could enhance DOX-induced apoptosis, while knockdown of IK1 attenuated DOX-induced apoptosis in leukemic cells. Further experiments demonstrated that IK1 sensitized leukemic cells to DOX-induced apoptosis, probably through upregulation of caspase-9. These data suggest that high expression levels of IK1 may be a potential biomarker to predict responses of leukemia patients to treatment with chemotherapy.

  15. Serial analysis of gene expression in a microglial cell line.

    PubMed

    Inoue, H; Sawada, M; Ryo, A; Tanahashi, H; Wakatsuki, T; Hada, A; Kondoh, N; Nakagaki, K; Takahashi, K; Suzumura, A; Yamamoto, M; Tabira, T

    1999-12-01

    We used the serial analysis of gene expression (SAGE) method to systematically analyze transcripts present in a microglial cell line. Over 10,000 SAGE tags were sequenced, and shown to represent 6,013 unique transcripts. Among the diverse transcripts that had not been previously detected in microglia were those for cytokines such as endothelial monocyte-activating polypeptide I (EMAP I), and for cell surface antigens, including adhesion molecules such as CD9, CD53, CD107a, CD147, CD162 and mast cell high affinity IgE receptor. In addition, we detected transcripts that were characteristic of hematopoietic cells or mesodermal structures, such as E3 protein, A1, EN-7, B94, and ufo. Furthermore, the profile contained a transcript, Hn1, that is important in hematopoietic cells and neurological development (Tang et al. Mamm Genome 8:695-696, 1997), suggesting the probable neural differentiation of microglia from the hematopoietic system in development. Messenger RNA expression of these genes was confirmed by RT-PCR in primary cultures of microglia. Significantly, this is the first systematic profiling of the genes expressed in a microglial cell line. The identification and further characterization of the genes described here should provide potential new targets for the study of microglial biology. PMID:10559785

  16. AIRE expressing marginal zone dendritic cells balances adaptive immunity and T-follicular helper cell recruitment.

    PubMed

    Lindmark, Evelina; Chen, Yunying; Georgoudaki, Anna-Maria; Dudziak, Diana; Lindh, Emma; Adams, William C; Loré, Karin; Winqvist, Ola; Chambers, Benedict J; Karlsson, Mikael C I

    2013-05-01

    Autoimmune polyendocrine syndrome Type I (APS I) results in multiple endocrine organ destruction and is caused by mutations in the Autoimmune regulator gene (AIRE). In the thymic stroma, cells expressing the AIRE gene dictate T cell education and central tolerance. Although this function is the most studied, AIRE is also expressed in the periphery in DCs and stromal cells. Still, how AIRE regulated transcription modifies cell behaviour in the periphery is largely unknown. Here we show that AIRE is specifically expressed by 33D1(+) DCs and dictates the fate of antibody secreting cell movement within the spleen. We also found that AIRE expressing 33D1(+) DCs expresses self-antigens as exemplified by the hallmark gene insulin. Also, as evidence for a regulatory function, absence of Aire in 33D1(+) DCs led to reduced levels of the chemokine CXCL12 and increased co-stimulatory properties. This resulted in altered activation and recruitment of T-follicular helper cells and germinal centre B cells. The altered balance leads to a change of the early response to a T cell-dependent antigen in Aire(-/-) mice. These findings add to the understanding of how specific DC subtypes regulate the early responses during T cell-dependent antibody responses within the spleen and further define the role of AIRE in the periphery as regulator of self-antigen expression and lymphocyte migration. PMID:23265639

  17. Gene cataloging and expression profiling in human gastric cancer cells by expressed sequence tags.

    PubMed

    Kim, Nam-Soon; Hahn, Yoonsoo; Oh, Jung-Hwa; Lee, Ju-Yeon; Oh, Kyung-Jin; Kim, Jeong-Min; Park, Hong-Seog; Kim, Sangsoo; Song, Kyu-Sang; Rho, Seung-Moo; Yoo, Hyang-Sook; Kim, Yong Sung

    2004-06-01

    To understand the molecular mechanism associated with gastric carcinogenesis, we identified genes expressed in gastric cancer cell lines and tissues. Of 97,609 high-quality ESTs sequenced from 36 cDNA libraries, 92,545 were coalesced into 10,418 human Unigene clusters (Build 151). The gene expression profile was produced by counting the cluster frequencies in each library. Although the profiles of highly expressed genes varied greatly from library to library, those genes related to cell structure formation, heat shock proteins, the glycolysis pathway, and the signaling pathway were highly represented in human gastric cancer cell lines and in primary tumors. Conversely, the genes encoding immunoglobulins, ribosomal proteins, and digestive proteins were down-regulated in gastric cancer cell lines and tissues compared to normal tissues. The transcription levels of some of these genes were confirmed by RT-PCR. We found that genes related to cell adhesion, apoptosis, and cytoskeleton formation were particularly up-regulated in the gastric cancer cell lines established from malignant ascites compared to those from primary tumors. This comprehensive molecular profiling of human gastric cancer should be useful for elucidating the genetic events associated with human gastric cancer. PMID:15177556

  18. Human clusterin gene expression is confined to surviving cells during in vitro programmed cell death.

    PubMed Central

    French, L E; Wohlwend, A; Sappino, A P; Tschopp, J; Schifferli, J A

    1994-01-01

    Clusterin is a serum glycoprotein endowed with cell aggregating, complement inhibitory, and lipid binding properties, and is also considered as a specific marker of dying cells, its expression being increased in various tissues undergoing programmed cell death (PCD). However, no study has so far directly shown that cells expressing clusterin in these tissues are actually apoptotic as defined by morphological and biochemical criteria. We have studied cellular clusterin gene expression in vitro using three different models of PCD: (a) ultraviolet B (UV-B) irradiation of human U937, HeLa, and A431 cell lines, (b) in vitro aging of human peripheral blood neutrophils (PMNs), and (c) dexamethasone-induced cell death of the human lymphoblastoid cell line CEM-C7. In all three models, the classical morphological and biochemical features of PCD observed did not correlate with an increase, but with either a marked decrease or an absence of clusterin gene expression as assessed by Northern blot analysis. In situ hybridization of U937 and A431 cells after UV-B irradiation revealed, in addition, that only morphologically normal cells that are surviving continue to express the clusterin gene. Our results demonstrate that in the human myeloid, lymphoid, and epithelial cell types studied, clusterin gene expression is not a prerequisite to their death by apoptosis. In addition, and most interestingly, in situ hybridization of U937 and A431 cells revealed that only surviving cells express the clusterin gene after the induction of PCD, thus providing novel evidence suggesting that clusterin may be associated with cell survival within tissues regressing as a consequence of PCD. Images PMID:8113419

  19. PDGFR-{beta} expression in small cell lung cancer patients

    SciTech Connect

    Shinohara, Eric T.; Gonzalez, Adriana; Massion, Pierre P.; Olson, Sandra J.; Albert, Jeffrey M.; Shyr, Yu; Carbone, David P.; Johnson, David H.; Hallahan, Dennis E.; Lu Bo . E-mail: bo.lu@vanderbilt.edu

    2007-02-01

    Background: Platelet derived growth factor (PDGF) and PDGFR-{beta} are expressed and have been found to have prognostic value in several human cancers. Data in non-small-cell cancer cell lines have suggested that PDGFR is a therapeutic target for drug development. In the current study PDGFR-{beta} expression and prognostic value in small cell lung cancer (SCLC) was investigated. Methods and Materials: Paraffin-embedded tissue blocks from 53 patients with limited and extensive stage SCLC were obtained for immunohistochemical staining. Tumors from each patient were sampled 3 times and stained with PDGFR-{beta} specific antibody. Patients were divided into low and high staining groups based on intensity. Results: There was high intensity PDGFR-{beta} staining in 20 patients with SCLC. Another 29 expressed low intensity PDGFR-{beta} staining, with only 4 patients showing no PDGFR-{beta} staining. There was no statistically significant difference in 5 year overall survival between patients with low levels of PDGFR-{beta} staining vs. those with high level staining SCLC tumors (p = 0.538). Conclusions: The present study found that the majority of SCLC patients express, at least, a low level of PDGF-{beta}. However, the level of PDGFR-{beta} expression was not a statistically significant predictor of 5 year overall survival in SCLC.

  20. Live-Cell, Temporal Gene Expression Analysis of Osteogenic Differentiation in Adipose-Derived Stem Cells

    PubMed Central

    Desai, Hetal V.; Voruganti, Indu S.; Jayasuriya, Chathuraka; Chen, Qian

    2014-01-01

    Adipose-derived stem cells (ASCs) are a widely investigated type of mesenchymal stem cells with great potential for musculoskeletal regeneration. However, the use of ASCs is complicated by their cellular heterogeneity, which exists at both the population and single-cell levels. This study demonstrates a live-cell assay to investigate gene expression in ASCs undergoing osteogenesis using fluorescently tagged DNA hybridization probes called molecular beacons. A molecular beacon was designed to target the mRNA sequence for alkaline phosphatase (ALPL), a gene characteristically expressed during early osteogenesis. The percentage of cells expressing this gene in a population was monitored daily to quantify the uniformity of the differentiation process. Differentiating ASC populations were repeatedly measured in a nondestructive fashion over a 10-day period to obtain temporal gene expression data. Results showed consistent expression patterns for the investigated osteogenic genes in response to induction medium. Peak signal level, indicating when the most cells expressed ALPL at once, was observed on days 3–5. The differentiation response of sample populations was generally uniform when assessed on a well-by-well basis over time. The expression of alkaline phosphatase is consistent with previous studies of osteogenic differentiation, suggesting that molecular beacons are a viable means of monitoring the spatiotemporal gene expression of live, differentiating ASCs. PMID:24367991

  1. Calretinin mediates apoptosis in small cell lung cancer cells expressing tetraspanin CD9☆

    PubMed Central

    He, Ping; Kuhara, Hanako; Tachibana, Isao; Jin, Yingji; Takeda, Yoshito; Tetsumoto, Satoshi; Minami, Toshiyuki; Kohmo, Satoshi; Hirata, Haruhiko; Takahashi, Ryo; Inoue, Koji; Nagatomo, Izumi; Kida, Hiroshi; Kijima, Takashi; Naka, Tetsuji; Morii, Eiichi; Kawase, Ichiro; Kumanogoh, Atsushi

    2013-01-01

    A majority of small cell lung cancer (SCLC) cells lack a metastasis suppressor, tetraspanin CD9, and CD9 expression promotes their apoptosis. By a proteomics-based approach, we compared an SCLC cell line with its CD9 transfectant and found that a calcium-binding neuronal protein, calretinin, is upregulated in CD9-positive SCLC cells. Ectopic or anticancer drug-induced CD9 expression upregulated calretinin, whereas CD9 knockdown down-regulated calretinin in SCLC cells. When calretinin was knocked down, CD9-positive SCLC cells revealed increased Akt phosphorylation and decreased apoptosis. These results suggest that CD9 positively regulates the expression of calretinin that mediates proapoptotic effect in SCLC cells. PMID:23772398

  2. Firefly luciferase gene: structure and expression in mammalian cells.

    PubMed Central

    de Wet, J R; Wood, K V; DeLuca, M; Helinski, D R; Subramani, S

    1987-01-01

    The nucleotide sequence of the luciferase gene from the firefly Photinus pyralis was determined from the analysis of cDNA and genomic clones. The gene contains six introns, all less than 60 bases in length. The 5' end of the luciferase mRNA was determined by both S1 nuclease analysis and primer extension. Although the luciferase cDNA clone lacked the six N-terminal codons of the open reading frame, we were able to reconstruct the equivalent of a full-length cDNA using the genomic clone as a source of the missing 5' sequence. The full-length, intronless luciferase gene was inserted into mammalian expression vectors and introduced into monkey (CV-1) cells in which enzymatically active firefly luciferase was transiently expressed. In addition, cell lines stably expressing firefly luciferase were isolated. Deleting a portion of the 5'-untranslated region of the luciferase gene removed an upstream initiation (AUG) codon and resulted in a twofold increase in the level of luciferase expression. The ability of the full-length luciferase gene to activate cryptic or enhancerless promoters was also greatly reduced or eliminated by this 5' deletion. Assaying the expression of luciferase provides a rapid and inexpensive method for monitoring promoter activity. Depending on the instrumentation employed to detect luciferase activity, we estimate this assay to be from 30- to 1,000-fold more sensitive than assaying chloramphenicol acetyltransferase expression. Images PMID:3821727

  3. Profiling Eph receptor expression in cells and tissues

    PubMed Central

    Noberini, Roberta; Rubio de la Torre, Elena; Pasquale, Elena B.

    2012-01-01

    The Eph receptor tyrosine kinase family includes many members, which are often expressed together in various combinations and can promiscuously interact with multiple ephrin ligands, generating intricate networks of intracellular signals that control physiological and pathological processes. Knowing the entire repertoire of Eph receptors and ephrins expressed in a biological sample is important when studying their biological roles. Moreover, given the correlation between Eph receptor/ephrin expression and cancer pathogenesis, their expression patterns could serve important diagnostic and prognostic purposes. However, profiling Eph receptor and ephrin expression has been challenging. Here we describe a novel and straightforward approach to catalog the Eph receptors present in cultured cells and tissues. By measuring the binding of ephrin Fc fusion proteins to Eph receptors in ELISA and pull-down assays, we determined that a mixture of four ephrins is suitable for isolating both EphA and EphB receptors in a single pull-down. We then used mass spectrometry to identify the Eph receptors present in the pull-downs and estimate their relative levels. This approach was validated in cultured human cancer cell lines, human tumor xenograft tissue grown in mice, and mouse brain tissue. The new mass spectrometry approach we have developed represents a useful tool for the identification of the spectrum of Eph receptors present in a biological sample and could also be extended to profiling ephrin expression. PMID:22568954

  4. TPD52 expression increases neutral lipid storage within cultured cells.

    PubMed

    Kamili, Alvin; Roslan, Nuruliza; Frost, Sarah; Cantrill, Laurence C; Wang, Dongwei; Della-Franca, Austin; Bright, Robert K; Groblewski, Guy E; Straub, Beate K; Hoy, Andrew J; Chen, Yuyan; Byrne, Jennifer A

    2015-09-01

    Tumor protein D52 (TPD52) is amplified and/or overexpressed in cancers of diverse cellular origins. Altered cellular metabolism (including lipogenesis) is a hallmark of cancer development, and protein-protein associations between TPD52 and known regulators of lipid storage, and differential TPD52 expression in obese versus non-obese adipose tissue, suggest that TPD52 might regulate cellular lipid metabolism. We found increased lipid droplet numbers in BALB/c 3T3 cell lines stably expressing TPD52, compared with control and TPD52L1-expressing cell lines. TPD52-expressing 3T3 cells showed increased fatty acid storage in triglyceride (from both de novo synthesis and uptake) and formed greater numbers of lipid droplets upon oleic acid supplementation than control cells. TPD52 colocalised with Golgi, but not endoplasmic reticulum (ER), markers and also showed partial colocalisation with lipid droplets coated with ADRP (also known as PLIN2), with a proportion of TPD52 being detected in the lipid droplet fraction. Direct interactions between ADRP and TPD52, but not TPD52L1, were demonstrated using the yeast two-hybrid system, with ADRP-TPD52 interactions confirmed using GST pulldown assays. Our findings uncover a new isoform-specific role for TPD52 in promoting intracellular lipid storage, which might be relevant to TPD52 overexpression in cancer. PMID:26183179

  5. Cell surface expression and biosynthesis of epithelial Na+ channels.

    PubMed Central

    Prince, L S; Welsh, M J

    1998-01-01

    The epithelial Na+ channel (ENaC) complex is composed of three homologous subunits: alpha, beta and gamma. Mutations in ENaC subunits can increase the number of channels on the cell surface, causing a hereditary form of hypertension called Liddle's syndrome, or can decrease channel activity, causing pseudohypoaldosteronism type I, a salt-wasting disease of infancy. To investigate surface expression, we studied ENaC subunits expressed in COS-7 and HEK293 cells. Using surface biotinylation and protease sensitivity, we found that when individual ENaC subunits are expressed alone, they traffic to the cell surface. The subunits are glycosylated with high-mannose oligosaccharides, but seem to have the carbohydrate removed before they reach the cell surface. Moreover, subunits form a complex that cannot be disrupted by several non-ionic detergents. The pattern of glycosylation and detergent solubility/insolubility persists when the N-teminal and C-terminal cytoplasmic regions of ENaC are removed. With co-expression of all three ENaC subunits, the insoluble complex is the predominant species. These results show that ENaC and its family members are unique in their trafficking, biochemical characteristics and post-translational modifications. PMID:9841884

  6. Differential expression and interaction of host factors augment HIV-1 gene expression in neonatal mononuclear cells

    SciTech Connect

    Sundaravaradan, Vasudha; Mehta, Roshni; Harris, David T.; Zack, Jerome A.; Ahmad, Nafees

    2010-04-25

    We have previously shown a higher level of HIV-1 replication and gene expression in neonatal (cord) blood mononuclear cells (CBMC) compared with adult blood cells (PBMC), which could be due to differential expression of host factors. We performed the gene expression profile of CBMC and PBMC and found that 8013 genes were expressed at higher levels in CBMC than PBMC and 8028 genes in PBMC than CBMC, including 1181 and 1414 genes upregulated after HIV-1 infection in CBMC and PBMC, respectively. Several transcription factors (NF-kappaB, E2F, HAT-1, TFIIE, Cdk9, Cyclin T1), signal transducers (STAT3, STAT5A) and cytokines (IL-1beta, IL-6, IL-10) were upregulated in CBMC than PBMC, which are known to influence HIV-1 replication. In addition, a repressor of HIV-1 transcription, YY1, was down regulated in CBMC than PBMC and several matrix metalloproteinase (MMP-7, -12, -14) were significantly upregulated in HIV-1 infected CBMC than PBMC. Furthermore, we show that CBMC nuclear extracts interacted with a higher extent to HIV-1 LTR cis-acting sequences, including NF-kappaB, NFAT, AP1 and NF-IL6 compared with PBMC nuclear extracts and retroviral based short hairpin RNA (shRNA) for STAT3 and IL-6 down regulated their own and HIV-1 gene expression, signifying that these factors influenced differential HIV-1 gene expression in CBMC than PBMC.

  7. PROFILES OF GENE EXPRESSION ASSOCIATED WITH TETRACYCLINE OVER EXPRESSION OF HSP70 IN MCF-7 BREAST CANCER CELLS

    EPA Science Inventory

    Profiles of gene expression associated with tetracycline over expression of HSP70 in MCF-7 breast cancer cells.

    Heat shock proteins (HSPs) protect cells from damage through their function as molecular chaperones. Some cancers reveal high levels of HSP70 expression in asso...

  8. Enhancement of endothelial cell migration by constitutively active LPA{sub 1}-expressing tumor cells

    SciTech Connect

    Kitayoshi, Misaho; Kato, Kohei; Tanabe, Eriko; Yoshikawa, Kyohei; Fukui, Rie; Fukushima, Nobuyuki; Tsujiuchi, Toshifumi

    2012-06-01

    Highlights: Black-Right-Pointing-Pointer Mutated LPA{sub 1} stimulates cell migration of endothelial cells. Black-Right-Pointing-Pointer VEGF expressions are increased by mutated LPA{sub 1}. Black-Right-Pointing-Pointer LPA signaling via mutated LPA{sub 1} is involved in angiogenesis. Black-Right-Pointing-Pointer Mutated LPA{sub 1} promotes cancer cell progression. -- Abstract: Lysophosphatidic acid (LPA) receptors belong to G protein-coupled transmembrane receptors (LPA receptors; LPA{sub 1} to LPA{sub 6}). They indicate a variety of cellular response by the interaction with LPA, including cell proliferation, migration and differentiation. Recently, we have reported that constitutive active mutated LPA{sub 1} induced the strong biological effects of rat neuroblastoma B103 cells. In the present study, we examined the effects of mutated LPA{sub 1} on the interaction between B103 cells and endothelial F-2 cells. Each LPA receptor expressing B103 cells were maintained in serum-free DMEM and cell motility assay was performed with a Cell Culture Insert. When F-2 cells were cultured with conditioned medium from Lpar1 and Lpar3-expressing cells, the cell motility of F-2 cells was significantly higher than control cells. Interestingly, the motile activity of F-2 cells was strongly induced by mutated LPA{sub 1} than other cells, correlating with the expression levels of vascular endothelial growth factor (Vegf)-A and Vegf-C. Pretreatment of LPA signaling inhibitors inhibited F-2 cell motility stimulated by mutated LPA{sub 1}. These results suggest that activation of LPA signaling via mutated LPA{sub 1} may play an important role in the promotion of angiogenesis in rat neuroblastoma cells.

  9. Antitumor effects of celecoxib in COX-2 expressing and non-expressing canine melanoma cell lines

    PubMed Central

    Seo, Kyoung-won; Coh, Ye-rin; Rebhun, Robert B.; Ahn, Jin-ok; Han, Sei-Myung; Lee, Hee-woo; Youn, Hwa-Young

    2016-01-01

    Cyclooxygenase-2 (COX-2) is a potential target for chemoprevention and cancer therapy. Celecoxib, a selective COX-2 inhibitor, inhibits cell growth of various types of human cancer including malignant melanoma. In dogs, oral malignant melanoma represents the most common oral tumor and is often a fatal disease. Therefore, there is a desperate need to develop additional therapeutic strategies. The purpose of this study was to investigate the anticancer effects of celecoxib on canine malignant melanoma cell lines that express varying levels of COX-2. Celecoxib induced a significant anti-proliferative effect in both LMeC and CMeC-1 cells. In the CMeC cells, treatment of 50 µM celecoxib caused an increase in cells in the G0/G1 and a decreased proportion of cells in G-2 phase. In the LMeC cells, 50 µM of celecoxib led to an increase in the percentage of cells in the sub-G1 phase and a significant activation of caspase-3 when compared to CMeC-1 cells. In conclusion, these results demonstrate that celecoxib exhibits antitumor effects on canine melanoma LMeC and CMeC-1 cells by induction of G1-S cell cycle arrest and apoptosis. Our data suggest that celecoxib might be effective as a chemotherapeutic agent against canine malignant melanoma. PMID:24656746

  10. Altered enteroendocrine cell expression in T cell receptor alpha chain knock-out mice.

    PubMed

    Rubin, D C; Zhang, H; Qian, P; Lorenz, R G; Hutton, K; Peters, M G

    2000-10-15

    Mice lacking T cell receptor alpha chain (TCRalpha(-/-)) develop inflammation of the colon. We have examined the effect of this inflammation on the colonic epithelium by studying markers of epithelial cuff, enteroendocrine, and immune cell differentiation. Using immunohistochemical techniques, colons were compared in normal C57/BL6 and murine TCR alpha(-/-) mice aged 2 and 3 weeks and 3-11 months. TCR alpha(-/-) mice aged 3-11 months had histologic evidence of inflammation with increased expression of CD45, CD4+, CD8+, and B220+ cells and a decrease in expression of IgA+ cells. There was a decrease in the number of cholecystokinin, serotonin, and neurotensin enteroendocrine expressing cells in the colon of TCR alpha(-/-) mice. These changes were not present in 2-3-week-old suckling/weaning mice. In contrast, peptide tyrosine tyrosine (PYY), glucagon-like peptide-1, and gastrin expression did not change and small intestinal enteroendocrine cells remained unaltered. The change in colonic enteroendocrine cell expression appears to be a specific response, since only a subset of these cells was altered, and the epithelium was intact by histologic analysis. The absence of functional T cells in TCR alpha(-/-) colon has a marked effect on differentiation of a specific subpopulation of enteroendocrine cells, prior to loss of integrity of the epithelium. PMID:11054861

  11. Testosterone regulates FGF-2 expression during testis maturation by an IRES-dependent translational mechanism.

    PubMed

    Gonzalez-Herrera, Irma G; Prado-Lourenco, Leonel; Pileur, Frédéric; Conte, Caroline; Morin, Aurélie; Cabon, Florence; Prats, Hervé; Vagner, Stephan; Bayard, Francis; Audigier, Sylvie; Prats, Anne-Catherine

    2006-03-01

    Spermatogenesis is a complex process involving cell proliferation, differentiation, and apoptosis. Fibroblast growth factor 2 (FGF-2) is involved in testicular function, but its role in spermatogenesis has not been fully documented. The control of FGF-2 expression particularly occurs at the translational level, by an internal ribosome entry site (IRES)-dependent mechanism driving the use of alternative initiation codons. To study IRES activity regulation in vivo, we have developed transgenic mice expressing a bicistronic construct coding for two luciferase genes. Here, we show that the FGF-2 IRES is age-dependently activated in mouse testis, whereas EMCV and c-myc IRESs are not. Real-time PCR confirms that this regulation is translational. By using immunohistological techniques, we demonstrate that FGF-2 IRES stimulation occurs in adult, but not in immature, type-A spermatogonias. This is correlated with activation of endogenous FGF-2 expression in spermatogonia; whereas FGF-2 mRNA transcription is known to decrease in adult testis. Interestingly, the FGF-2 IRES activation is triggered by testosterone and is partially inhibited by siRNA directed against the androgen receptor. Two-dimensional analysis of proteins bound to the FGF-2 mRNA 5'UTR after UV cross-linking reveals that testosterone treatment correlates with the binding of several proteins. These data suggest a paracrine loop where IRES-dependent FGF-2 expression, stimulated by Sertoli cells in response to testosterone produced by Leydig cells, would in turn activate Leydig function and testosterone production. In addition, nuclear FGF-2 isoforms could be involved in an intracrine function of FGF-2 in the start of spermatogenesis, mitosis, or meiosis initiation. This report demonstrates that mRNA translation regulation by an IRES-dependent mechanism participates in a physiological process. PMID:16423876

  12. Immunotoxin BL22 induces apoptosis in mantle cell lymphoma (MCL) cells dependent on Bcl-2 expression.

    PubMed

    Bogner, Christian; Dechow, Tobias; Ringshausen, Ingo; Wagner, Michaela; Oelsner, Madlen; Lutzny, Gloria; Licht, Thomas; Peschel, Christian; Pastan, Ira; Kreitman, Robert J; Decker, Thomas

    2010-01-01

    Mantle cell lymphoma (MCL) is an incurable mature B cell proliferation, combining the unfavourable clinical features of aggressive and indolent lymphomas. The blastic variant of MCL has an even worse prognosis and new treatment options are clearly needed. We analysed the effects of BL22, an immunotoxin composed of the Fv portion of an anti- CD22 antibody fused to a 38-kDa Pseudomonas exotoxin-A fragment on four MCL cell lines as well as on primary cells of four MCL patients. Apoptosis induction by BL22 was much more pronounced in MCL cell lines with low Bcl-2 expression (NCEB-1, JeKo-1 and JVM-2) compared to Granta-519 cells with high Bcl-2 expression. While the expression of the antiapoptotic protein Mcl-1 declined (NCEB-1, Granta-519), Bcl-2 levels remained unchanged in Granta-519 cells. However transfection of BCL2 cDNA into NCEB-1, JeKo-1 and JVM-2 cells significantly reduced BL22-mediated toxicity. Accordingly we examined the effects of Bcl-2 inactivation in Granta-519 cells using siRNA. Indeed, apoptosis induction was strongly enhanced in Granta-519 cells with silenced Bcl-2. Our results were confirmed in freshly isolated MCL-cells from patients with leukaemic MCL. We conclude that Bcl-2 expression is important for mediating resistance against the immunotoxin BL22 in MCL cells. PMID:19821820

  13. Proteomics Based Identification of Cell Migration Related Proteins in HBV Expressing HepG2 Cells

    PubMed Central

    Feng, Huixing; Li, Xi; Chan, Vincent; Chen, Wei Ning

    2014-01-01

    Proteomics study was performed to investigate the specific protein expression profiles of HepG2 cells transfected with mutant HBV compared with wildtype HBV genome, aiming to identify the specific functions of SH3 binding domain (proline rich region) located in HBx. In addition to the cell movement and kinetics changes due to the expression of HBV genome we have observed previously, here we further targeted to explore the specific changes of cellular proteins and potential intracellular protein interactions, which might provide more information of the potential cellular mechanism of the differentiated cell movements. Specific changes of a number of proteins were shown in global protein profiling in HepG2 cells expressing wildtype HBV, including cell migration related proteins, and interestingly the changes were found recovered by SH3 binding domain mutated HBV. The distinctive expressions of proteins were validated by Western blot analysis. PMID:24763314

  14. Single-cell gene expression profiling reveals functional heterogeneity of undifferentiated human epidermal cells

    PubMed Central

    Tan, David W. M.; Jensen, Kim B.; Trotter, Matthew W. B.; Connelly, John T.; Broad, Simon; Watt, Fiona M.

    2013-01-01

    Human epidermal stem cells express high levels of β1 integrins, delta-like 1 (DLL1) and the EGFR antagonist LRIG1. However, there is cell-to-cell variation in the relative abundance of DLL1 and LRIG1 mRNA transcripts. Single-cell global gene expression profiling showed that undifferentiated cells fell into two clusters delineated by expression of DLL1 and its binding partner syntenin. The DLL1+ cluster had elevated expression of genes associated with endocytosis, integrin-mediated adhesion and receptor tyrosine kinase signalling. Differentially expressed genes were not independently regulated, as overexpression of DLL1 alone or together with LRIG1 led to the upregulation of other genes in the DLL1+ cluster. Overexpression of DLL1 and LRIG1 resulted in enhanced extracellular matrix adhesion and increased caveolin-dependent EGFR endocytosis. Further characterisation of CD46, one of the genes upregulated in the DLL1+ cluster, revealed it to be a novel cell surface marker of human epidermal stem cells. Cells with high endogenous levels of CD46 expressed high levels of β1 integrin and DLL1 and were highly adhesive and clonogenic. Knockdown of CD46 decreased proliferative potential and β1 integrin-mediated adhesion. Thus, the previously unknown heterogeneity revealed by our studies results in differences in the interaction of undifferentiated basal keratinocytes with their environment. PMID:23482486

  15. Higher expression of SIRT1 induced resistance of esophageal squamous cell carcinoma cells to cisplatin

    PubMed Central

    Shi, Qintong; Wang, Wengong

    2015-01-01

    Background High expression of Sirtuin type 1 (SIRT1) exists in some cancer cells. However, it is still unclear whether SIRT1 affects the sensitivity of esophageal cancer cells to cisplatin. This study was designed to explore the relationship between SIRT1 expression and resistance of esophageal squamous cell carcinoma (ESCC) cells to cisplatin and reveal the underlying mechanism. Methods The tissue samples of 68 ESCC patients were collected from Nanjing Drum Tower Hospital, China. All the patients had undergone cisplatin based combination chemotherapy. The expression of SIRT1and Noxa in tissue samples were analyzed by quantitative real-time reverse PCR (qRT-PCR) and Western blot. Human ESCC cell line (ECa9706 cells) was cultured and a cisplatin-resistant subline (ECa9706-CisR cells) was established by continuous exposure to cisplatin at different concentrations. The expression of SIRT1 and Noxa in both cell lines was analyzed by qRT-PCR and Western blot. siRNA technology was utilized to down-regulate the SIRT1 expression in ECa9706-CisR cells. The influence of SIRT1 silence on sensitivity of ECa9706-CisR cells to cisplatin was confirmed using CCK-8 assay and flow cytometry. Furthermore, the level change of Noxa after SIRT1 silence in ECa9706-CisR cells was determined by qRT-PCR and Western blot. Result SIRT1 and Noxa expression in chemo-resistant patients was significantly increased and decreased respectively, compared with chemo-sensitive patients. SIRT1 expression in ECa9706-CisR cells was significantly increased with a lower Noxa level, compared with normal ECa9706 cells. Cisplatin 5 µM could cause proliferation inhibition, G2/M phase arrest and apoptosis in ECa9706-CisR cells and these effects could be enhanced dramatically by SIRT1 silencing. Moreover, Noxa expression was increased after treated with SIRT1 siRNA. Conclusions Over-expression of SIRT1 may cause resistance of ESCC cells to cisplatin through the mechanism involved with Noxa expression. PMID

  16. Isolation of genes predominantly expressed in guard cells and epidermal cells of Nicotiana glauca.

    PubMed

    Smart, L B; Cameron, K D; Bennett, A B

    2000-04-01

    Guard cells are specialized and metabolically active cells which arise during the differentiation of the epidermis. Using Nicotiana glauca epidermal peels as a source of purified guard cells, we have constructed a cDNA library from guard cell RNA. In order to isolate genes that are predominantly expressed in guard cells, we performed a differential screen of this library, comparing the hybridization of a radiolabeled cDNA probe synthesized from guard cell RNA to that from a mesophyll cell cDNA probe. Sixteen clones were isolated based on their greater level of hybridization with the guard cell probe. Of these, eight had high homology to lipid transfer protein (LTP), two were similar to glycine-rich protein (GRP), and one displayed high homology to proline-rich proteins from Arabidopsis thaliana (AtPRP2, AtPRP4) and from potato guard cells (GPP). Northern analysis confirmed that one or more NgLTP genes, NgGRP1, and NgGPP1 are all differentially expressed, with highest levels in guard cells, and low or undetectable levels in mesophyll cells and in roots. In addition, all are induced to some degree in drought-stressed guard cells. NgLTP and NgGRP1 expression was localized by in situ hybridization to the guard cells and pavement cells in the epidermis. NgGRP1 expression was also detected in cells of the vasculature. Genomic Southern analysis indicated that LTP is encoded by a family of highly similar genes in N. glauca. This work has identified members of a subset of epidermis- and guard cell-predominant genes, whose protein products are likely to contribute to the unique properties acquired by guard cells and pavement cells during differentiation. PMID:10890533

  17. Pancreatic beta cells express a diverse set of homeobox genes.

    PubMed Central

    Rudnick, A; Ling, T Y; Odagiri, H; Rutter, W J; German, M S

    1994-01-01

    Homeobox genes, which are found in all eukaryotic organisms, encode transcriptional regulators involved in cell-type differentiation and development. Several homeobox genes encoding homeodomain proteins that bind and activate the insulin gene promoter have been described. In an attempt to identify additional beta-cell homeodomain proteins, we designed primers based on the sequences of beta-cell homeobox genes cdx3 and lmx1 and the Drosophila homeodomain protein Antennapedia and used these primers to amplify inserts by PCR from an insulinoma cDNA library. The resulting amplification products include sequences encoding 10 distinct homeodomain proteins; 3 of these proteins have not been described previously. In addition, an insert was obtained encoding a splice variant of engrailed-2, a homeodomain protein previously identified in the central nervous system. Northern analysis revealed a distinct pattern of expression for each homeobox gene. Interestingly, the PCR-derived clones do not represent a complete sampling of the beta-cell library because no inserts encoding cdx3 or lmx1 protein were obtained. Beta cells probably express additional homeobox genes. The abundance and diversity of homeodomain proteins found in beta cells illustrate the remarkable complexity and redundancy of the machinery controlling beta-cell development and differentiation. Images PMID:7991607

  18. Vitamin H-regulated transgene expression in mammalian cells.

    PubMed

    Weber, Wilfried; Bacchus, William; Daoud-El Baba, Marie; Fussenegger, Martin

    2007-01-01

    Although adjustable transgene expression systems are considered essential for future therapeutic and biopharmaceutical manufacturing applications, the currently available transcription control modalities all require side-effect-prone inducers such as immunosupressants, hormones and antibiotics for fine-tuning. We have designed a novel mammalian transcription-control system, which is reversibly fine-tuned by non-toxic vitamin H (also referred to as biotin). Ligation of vitamin H, by engineered Escherichia coli biotin ligase (BirA), to a synthetic biotinylation signal fused to the tetracycline-dependent transactivator (tTA), enables heterodimerization of tTA to a streptavidin-linked transrepressor domain (KRAB), thereby abolishing tTA-mediated transactivation of specific target promoters. As heterodimerization of tTA to KRAB is ultimately conditional upon the presence of vitamin H, the system is vitamin H responsive. Transgenic Chinese hamster ovary cells, engineered for vitamin H-responsive gene expression, showed high-level, adjustable and reversible production of a human model glycoprotein in bench-scale culture systems, bioreactor-based biopharmaceutical manufacturing scenarios, and after implantation into mice. The vitamin H-responsive expression systems showed unique band pass filter-like regulation features characterized by high-level expression at low (0-2 nM biotin), maximum repression at intermediate (100-1000 nM biotin), and high-level expression at increased (>100 000 nM biotin) biotin concentrations. Sequential ON-to-OFF-to-ON, ON-to-OFF and OFF-to-ON expression profiles with graded expression transitions can all be achieved by simply increasing the level of a single inducer molecule without exchanging the culture medium. These novel expression characteristics mediated by an FDA-licensed inducer may foster advances in therapeutic cell engineering and manufacturing of difficult-to-produce protein therapeutics. PMID:17827215

  19. Human vascular smooth muscle cells express a urate transporter.

    PubMed

    Price, Karen L; Sautin, Yuri Y; Long, David A; Zhang, Li; Miyazaki, Hiroki; Mu, Wei; Endou, Hitoshi; Johnson, Richard J

    2006-07-01

    An elevated serum uric acid is associated with the development of hypertension and renal disease. Renal regulation of urate excretion is largely controlled by URAT1 (SLC22A12), a member of the organic anion transporter superfamily. This study reports the specific expression of URAT1 on human aortic vascular smooth muscle cells, as assessed by reverse transcription-PCR and Western blot analysis. Expression of URAT1 was localized to the cell membrane. Evidence that the URAT1 transporter was functional was provided by the finding that uptake of 14C-urate was significantly inhibited in the presence of probenecid, an organic anion transporter inhibitor. It is proposed that URAT1 may provide a mechanism by which uric acid enters the human vascular smooth muscle cell, a finding that may be relevant to the role of uric acid in cardiovascular disease. PMID:16775029

  20. Stem Cell-Associated Marker Expression in Canine Hair Follicles.

    PubMed

    Gerhards, Nora M; Sayar, Beyza S; Origgi, Francesco C; Galichet, Arnaud; Müller, Eliane J; Welle, Monika M; Wiener, Dominique J

    2016-03-01

    Functional hair follicle (HF) stem cells (SCs) are crucial to maintain the constant recurring growth of hair. In mice and humans, SC subpopulations with different biomarker expression profiles have been identified in discrete anatomic compartments of the HF. The rare studies investigating canine HF SCs have shown similarities in biomarker expression profiles to that of mouse and human SCs. The aim of our study was to broaden the current repertoire of SC-associated markers and their expression patterns in the dog. We combined analyses on the expression levels of CD34, K15, Sox9, CD200, Nestin, LGR5 and LGR6 in canine skin using RT-qPCR, the corresponding proteins in dog skin lysates, and their expression patterns in canine HFs using immunohistochemistry. Using validated antibodies, we were able to define the location of CD34, Sox9, Keratin15, LGR5 and Nestin in canine HFs and confirm that all tested biomarkers are expressed in canine skin. Our results show similarities between the expression profile of canine, human and mouse HF SC markers. This repertoire of biomarkers will allow us to conduct functional studies and investigate alterations in the canine SC compartment of different diseases, like alopecia or skin cancer with the possibility to extend relevant findings to human patients. PMID:26739040

  1. Expression of cell cycle regulator cdk2ap1 suppresses tumor cell phenotype by non-cell autonomous mechanisms

    PubMed Central

    Zolochevska, Olga; Figueiredo, Marxa L.

    2009-01-01

    We evaluated the effect of expressing the cell cycle regulator cdk2ap1 in epithelial or stromal cell compartments to reduce SCC growth in vitro and in vivo. Cell autonomous and/or non-cell autonomous expression of cdk2ap1 reduced tumor growth and invasion and altered cell cycle, adhesion, invasion, angiogenesis, and apoptotic gene expression, as assessed by several in vitro phenotype assays, quantitative real time PCR, and in vivo molecular imaging using a novel three-way xenograft animal model. Our findings suggest that the interactions between cancer cells and fibroblasts that promote abnormal growth can be minimized by expressing cdk2ap1, supporting a novel concept by which tumor/growth suppressor genes can impact tumorigenesis phenotypes from non-cell autonomous interactions within the tumor microenvironment. PMID:19515604

  2. Characterization of TLX Expression in Neural Stem Cells and Progenitor Cells in Adult Brains

    PubMed Central

    Li, Shengxiu; Sun, Guoqiang; Murai, Kiyohito; Ye, Peng; Shi, Yanhong

    2012-01-01

    TLX has been shown to play an important role in regulating the self-renewal and proliferation of neural stem cells in adult brains. However, the cellular distribution of endogenous TLX protein in adult brains remains to be elucidated. In this study, we used immunostaining with a TLX-specific antibody to show that TLX is expressed in both neural stem cells and transit-amplifying neural progenitor cells in the subventricular zone (SVZ) of adult mouse brains. Then, using a double thymidine analog labeling approach, we showed that almost all of the self-renewing neural stem cells expressed TLX. Interestingly, most of the TLX-positive cells in the SVZ represented the thymidine analog-negative, relatively quiescent neural stem cell population. Using cell type markers and short-term BrdU labeling, we demonstrated that TLX was also expressed in the Mash1+ rapidly dividing type C cells. Furthermore, loss of TLX expression dramatically reduced BrdU label-retaining neural stem cells and the actively dividing neural progenitor cells in the SVZ, but substantially increased GFAP staining and extended GFAP processes. These results suggest that TLX is essential to maintain the self-renewing neural stem cells in the SVZ and that the GFAP+ cells in the SVZ lose neural stem cell property upon loss of TLX expression.Understanding the cellular distribution of TLX and its function in specific cell types may provide insights into the development of therapeutic tools for neurodegenerative diseases by targeting TLX in neural stem/progenitors cells. PMID:22952666

  3. Expression of TIA-1 and TIA-2 in T cell malignancies and T cell lymphocytosis.

    PubMed Central

    Matutes, E; Coelho, E; Aguado, M J; Morilla, R; Crawford, A; Owusu-Ankomah, K; Catovsky, D

    1996-01-01

    OBJECTIVE: To investigate the reactivity with TIA-1 and TIA-2, two monoclonal antibodies that recognise, respectively, granular structures in T lymphocytes and the T cell receptor chain in cells from a variety of T cell disorders. METHODS: Cytoplasmic staining with TIA-1 and TIA-2 was carried out by the immunoalkaline phosphatase anti-alkaline phosphatase technique in 67 cases with a T cell disorder: 31 large granular lymphocyte (LGL) leukaemia, nine T-prolymphocytic leukaemia (T-PLL), five Sezary syndrome, four peripheral T cell lymphoma (PTCL), 13 T cell lymphocytosis, and five T-acute lymphoblastic leukaemia (T-ALL). All had over 75% abnormal T cells which were CD2+, CD3+, CD5+, CD7+, and negative with B cell markers. RESULTS: TIA-1 was positive in 77% cases of LGL leukaemia and half of the PTCL and T-ALL, whereas it was negative in all Sezary syndrome and most T-PLL (8/9) and reactive T-lymphocytosis (10/13). In LGL leukaemia, TIA-1 was positive irrespective of the membrane phenotype, whether CD8+, CD4- or CD4+, CD8-, and was more often positive in cases where cells were CD16+, CD56+, or CD57+. TIA-2 was positive in 60% of cases encompassing all diagnostic types of T cell disorder. There was no correlation between TIA-2 expression and that of other T cell markers, activation antigens, and natural killer markers. CONCLUSIONS: The pattern of TIA-1 expression in T cell malignancies may help in the differential diagnosis among LGL leukaemia (high expression), T cell lymphocytosis and other T cell diseases (low expression). As TIA-2 is expressed in over 95% mature T lymphocytes and thymic cells, its assessment may be useful to demonstrate aberrant phenotypes which can be exploited for detecting minimal residual disease. Images PMID:8655683

  4. [The expression and significance of hnRNPD in esophageal squamous cell carcinoma cells].

    PubMed

    Geng, Yangyang; Zhang, Lulu; Xu, Miaomiao; Sheng, Wenjiong; Dong, Aijing; Cao, Jinming; Cao, Jianping

    2015-12-01

    Objective To investigate the expression of heterogeneous nuclear ribonucleoprotein D (hnRNPD) in esophageal squamous cell carcinoma (ESCC) tissues and the relationship between hnRNPD expression and the clinicopathological features of ESCC, and to study the effect of down-regulated hnRNPD on the proliferation of ESCC cells and explore its potential mechanism. Methods The expression of hnRNPD protein in ESCC tissues and the normal paracancerous tissues were detected by immunohistochemistry. The siRNA-hnRNPD was transfected into ESCC cells and the silence effect was verified by Western blotting. MTT assay and clone formation assay were used to evaluate the proliferation of ESCC cells after down-regulation of hnRNPD genes. Cell apoptosis was examined by annexin V-phycoerythrin/7-aminoactinomycin D (annexin V-PE/7-AAD) staining and flow cytometry. Results The expression of hnRNPD protein in ESCC tissues was significantly higher than that of the normal paracancerous tissues, and the expression was closely related with neoplasm staging. Down-regulation of hnRNPD inhibited the proliferation and clonality of ESCC cells. Compared with the control group, siRNA targeting hnRNPD significantly promoted cell apoptosis. Conclusion Down-regulation of hnRNPD inhibits the proliferation of ESCC cells by promoting cell apoptosis. PMID:26648300

  5. 'Fluorescent Cell Chip' for immunotoxicity testing: Development of the c-fos expression reporter cell lines

    SciTech Connect

    Trzaska, Dominika; Zembek, Patrycja; Olszewski, Maciej; Adamczewska, Violetta; Ulleras, Erik; Dastych, JarosIaw . E-mail: jdastych@cbm.pan.pl

    2005-09-01

    The Fluorescent Cell Chip for in vitro immunotoxicity testing employs cell lines derived from lymphocytes, mast cells, and monocytes-macrophages transfected with various EGFP cytokine reporter gene constructs. While cytokine expression is a valid endpoint for in vitro immunotoxicity screening, additional marker for the immediate-early response gene expression level could be of interest for further development and refinement of the Fluorescent Cell Chip. We have used BW.5147.3 murine thymoma transfected with c-fos reporter constructs to obtain reporter cell lines expressing ECFP under the control of murine c-fos promoter. These cells upon serum withdrawal and readdition and incubation with heavy metal compounds showed paralleled induction of c-Fos expression as evidenced by Real-Time PCR and ECFP fluorescence as evidenced by computer-supported fluorescence microscopy. In conclusion, we developed fluorescent reporter cell lines that could be employed in a simple and time-efficient screening assay for possible action of chemicals on c-Fos expression in lymphocytes. The evaluation of usefulness of these cells for the Fluorescent Cell Chip-based detection of immunotoxicity will require additional testing with a larger number of chemicals.

  6. Epithelial-Mesenchymal Transition Protein Expression in Basal Cell Adenomas and Basal Cell Adenocarcinomas.

    PubMed

    Tesdahl, Brennan A; Wilson, Thomas C; Hoffman, Henry T; Robinson, Robert A

    2016-06-01

    Basal cell adenomas and basal cell adenocarcinomas show marked histomorphologic similarity and are separated microscopically primarily by the invasive characteristics of the adenocarcinomas. We wished to explore potential differences in the expression of epithelial-mesenchymal transition associated proteins in these two tumor types. A tissue microarray was constructed utilizing 29 basal cell adenomas and 16 basal cell adenocarcinomas. Immunohistochemical expression of E-cadherin, beta-catenin, Twist 1 and vimentin were investigated. Both tumors expressed all proteins in a relatively similar manner. Nuclear beta-catenin was essentially limited to the abluminal cell populations in both tumor types. E-cadherin was limited largely to luminal locations but was more prevalent in the adenocarcinomas as compared to the adenomas. Primarily abluminal expression for vimentin was seen, sometimes present in an apical dot-like pattern. Distinct populations of cellular expression of these four markers of epithelial mesenchymal transition were present but were similar in locations in both tumors with no patterns discerned to separate basal cell adenoma from basal cell adenocarcinoma. Given these finding