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Testosterone synthesis

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https://www.readbyqxmd.com/read/28212445/long-term-effects-of-fetal-undernutrition-on-rat-heart-role-of-hypertension-and-oxidative-stress
#1
Pilar Rodríguez-Rodríguez, Angel L López de Pablo, Concha F García-Prieto, Beatriz Somoza, Begoña Quintana-Villamandos, José J Gómez de Diego, Perla Y Gutierrez-Arzapalo, David Ramiro-Cortijo, M Carmen González, Silvia M Arribas
BACKGROUND AND AIMS: Fetal undernutrition is a risk factor for heart disease in both genders, despite the protection of women against hypertension development. Using a rat model of maternal undernutrition (MUN) we aimed to assess possible sex differences in the development of cardiac alterations and the implication of hypertension and cardiac oxidative stress. METHODS: Male and female offspring from rats fed ad libitum (control) or with 50% of the normal daily intake during the second half of gestation (MUN) were used...
2017: PloS One
https://www.readbyqxmd.com/read/28193709/testosterone-represses-estrogen-signaling-by-upregulating-mir-22-a-mechanism-for-imbalanced-steroid-hormone-production-in-preeclampsia
#2
Xuan Shao, Yanlei Liu, Ming Liu, Yongqing Wang, Liying Yan, Hao Wang, Liyang Ma, Yu-Xia Li, Yangyu Zhao, Yan-Ling Wang
Preeclampsia, a multisystem syndrome occurring during mid- to late gestation in humans, is a leading cause of maternal and perinatal morbidity and mortality. Patients usually present with high circulating testosterone and reduced estradiol production, but the mechanisms remain unclear. Revealing the mechanism that modulating the imbalance of testosterone and estradiol in preeclampsia is of great value in understanding the cause of the disease. The placenta is the predominant source of steroid hormone production during gestation, and we observed markedly increased 17β-HSD3 (17β-hydroxysteroid dehydrogenase 3) levels and downregulated aromatase expression, the key enzymes responsible for synthesis of testosterone and estradiol, respectively, in preeclamptic placentas compared with controls...
February 13, 2017: Hypertension
https://www.readbyqxmd.com/read/28182747/investigation-of-the-in-vitro-and-in-vivo-efficiency-of-rm-532-105-a-17%C3%AE-hydroxysteroid-dehydrogenase-type-3-inhibitor-in-lapc-4-prostate-cancer-cell-and-tumor-models
#3
Lucie Carolle Kenmogne, Jenny Roy, René Maltais, Mélanie Rouleau, Bertrand Neveu, Frédéric Pouliot, Donald Poirier
In the fight against androgen-sensitive prostate cancer, the enzyme 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) is an attractive therapeutic target considering its key role in the formation of androgenic steroids. In this study, we attempted to assess the in vivo efficacy of the compound RM-532-105, an androsterone derivative developed as an inhibitor of 17β-HSD3, in the prostate cancer model of androgen-sensitive LAPC-4 cells xenografted in nude mice. RM-532-105 did not inhibit the tumor growth induced by 4-androstene-3,17-dione (4-dione); rather, the levels of the androgens testosterone (T) and dihydrotestosterone (DHT) increased within the tumors...
2017: PloS One
https://www.readbyqxmd.com/read/28179152/the-six-most-widely-used-selective-serotonin-reuptake-inhibitors-decrease-androgens-and-increase-estrogens-in-the-h295r-cell-line
#4
Cecilie Hurup Hansen, Lizette Weber Larsen, Amalie Møller Sørensen, Bent Halling-Sørensen, Bjarne Styrishave
Selective serotonin reuptake inhibitors (SSRIs) used as first line of treatment in major depressive disorder (MDD) are known to exert negative effects on the endocrine system and fertility. The aim of the present study was to investigate the possible endocrine disrupting effect of six SSRIs, fluoxetine, paroxetine, citalopram and its active enantiomer escitalopram, sertraline and fluvoxamine using the OECD standardized and validated human in vitro adrenocortical H295R cell assay. All the major steroids, including progestagens, corticoids, androgens and estrogens were analysed using a fully validated LC-MS/MS method...
February 5, 2017: Toxicology in Vitro: An International Journal Published in Association with BIBRA
https://www.readbyqxmd.com/read/28167972/cryptotanshinone-regulates-androgen-synthesis-through-the-erk-c-fos-cyp17-pathway-in-porcine-granulosa-cells
#5
Danfeng Ye, Meifang Li, Yuehui Zhang, Xinhua Wang, Hua Liu, Wanting Wu, Wanying Ma, Kewei Quan, Ernest H Y Ng, Xiaoke Wu, Maohua Lai, Hongxia Ma
The aim of the study is to investigate the molecular mechanism behind androgen reduction in porcine granulosa cells (pGCs) with Salvia miltiorrhiza Bunge extract cryptotanshinone. PGCs were isolated from porcine ovaries and identified. Androgen excess model of the pGCs was induced with the MAPK inhibitor PD98059 and then treated with cryptotanshinone. The testosterone level was measured by radioimmunoassay in the culture media. The protein levels of P-ERK1/2, c-Fos, and CYP17 in the cells were measured by western blot...
2017: Evidence-based Complementary and Alternative Medicine: ECAM
https://www.readbyqxmd.com/read/28146428/hypoxia-reduces-testosterone-synthesis-in-mouse-leydig-cells-by-inhibiting-nrf1-activated-star-expression
#6
Xueting Wang, Longlu Pan, Zhiran Zou, Dan Wang, Yapeng Lu, Zhangji Dong, Li Zhu
Male fertility disorders play a key role in half of all infertility cases. Reduction in testosterone induced by hypoxia might cause diseases in reproductive system and other organs. Hypoxic exposure caused a significant decrease of NRF1. Software analysis reported that the promoter region of steroidogenic acute regulatory protein (StAR) contained NRF1 binding sites, indicating NRF1 promoted testicular steroidogenesis. The purpose of this study is to determine NRF1 is involved in testosterone synthesis; and under hypoxia, the decrease of testosterone synthesis is caused by lower expression of NRF1...
January 27, 2017: Oncotarget
https://www.readbyqxmd.com/read/28142121/the-role-of-dietary-polyphenols-in-the-management-of-erectile-dysfunction-mechanisms-of-action
#7
REVIEW
Chinedum Eleazu, Nwite Obianuju, Kate Eleazu, Winner Kalu
The incidence of erectile dysfunction (ED) is on the increase and it is estimated that it will affect about 322 million men globally by the year 2025 if adequate measures are not taken to curb it. Natural polyphenols in plant based diets have gained public interest in recent times due to their roles in the prevention of various disease that implicate free radicals/reactive oxygen species and recently on ED. However, the role of polyphenols in the management of ED has not been explored due perhaps to limited data available...
January 28, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28122810/testosterone-prevents-protein-loss-via-the-hepatic-urea-cycle-in-human
#8
Teresa Lam, Anne Poljak, Mark McLean, Neha Bahl, Ken K Y Ho, Vita Birzniece
CONTEXT: The urea cycle is a rate limiting step for amino acid nitrogen elimination. The rate of urea synthesis is a true indicator of whole body protein catabolism. Testosterone reduces protein and nitrogen loss. The effect of testosterone on hepatic urea synthesis in humans has not been studied. OBJECTIVE: To determine whether testosterone reduces hepatic urea production. DESIGN: an open label study Patients and Intervention: Eight hypogonadal men were studied at baseline, and after two weeks of transdermal testosterone replacement (Testogel, 100 mg/day)...
January 25, 2017: European Journal of Endocrinology
https://www.readbyqxmd.com/read/28103392/a-peroxygenase-from-chaetomium-globosum-catalyzes-the-selective-oxygenation-of-testosterone
#9
Jan Kiebist, Kai-Uwe Schmidtke, Jörg Zimmermann, Harald Kellner, Nico Jehmlich, René Ullrich, Daniel Zänder, Martin Hofrichter, Katrin Scheibner
Unspecific peroxygenases (UPO, EC 1.11.2.1) secreted by fungi open an efficient way to selectively oxyfunctionalize diverse organic substrates including less activated hydrocarbons by transferring peroxide-borne oxygen. Herein, we investigated a cell-free approach to incorporate epoxy and hydroxyl functionalities directly into the bulky molecule of testosterone by a novel unspecific peroxygenase that was produced by the ascomycetous fungus Chaetomium globosum in a complex medium rich in carbon and nitrogen...
January 19, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/28065637/the-steroid-metabolite-16-%C3%AE-oh-androstenedione-generated-by-cyp21a2-serves-as-a-substrate-for-cyp19a1
#10
J Neunzig, M Milhim, L Schiffer, Y Khatri, J Zapp, A Sánchez-Guijo, M F Hartmann, S A Wudy, R Bernhardt
The 21-hydroxylase (CYP21A2) is a steroidogenic enzyme crucial for the synthesis of mineralo- and glucocorticoids. It is described to convert progesterone as well as 17-OH-progesterone, through a hydroxylation at position C21, into 11-deoxycorticosterone (DOC) and 11-deoxycortisol (RSS), respectively. In this study we unraveled CYP21A2 to have a broader steroid substrate spectrum than assumed. Utilizing a reconstituted in vitro system, consisting of purified human CYP21A2 and human cytochrome P450 reductase (CPR) we demonstrated that CYP21A2 is capable to metabolize DOC, RSS, androstenedione (A4) and testosterone (T)...
March 2017: Journal of Steroid Biochemistry and Molecular Biology
https://www.readbyqxmd.com/read/28056997/human-lh-and-hcg-stimulate-differently-the-early-signalling-pathways-but-result-in-equal-testosterone-synthesis-in-mouse-leydig-cells-in-vitro
#11
Laura Riccetti, Francesco De Pascali, Lisa Gilioli, Francesco Potì, Lavinia Beatrice Giva, Marco Marino, Simonetta Tagliavini, Tommaso Trenti, Flaminia Fanelli, Marco Mezzullo, Uberto Pagotto, Manuela Simoni, Livio Casarini
BACKGROUND: Human luteinizing hormone (LH) and chorionic gonadotropin (hCG) are glycoprotein hormones regulating development and reproductive functions by acting on the same receptor (LHCGR). We compared the LH and hCG activity in gonadal cells from male mouse in vitro, i.e. primary Leydig cells, which is a common tool used for gonadotropin bioassay. Murine Leydig cells are naturally expressing the murine LH receptor (mLhr), which binds human LH/hCG. METHODS: Cultured Leydig cells were treated by increasing doses of recombinant LH and hCG, and cell signaling, gene expression and steroid synthesis were evaluated...
January 5, 2017: Reproductive Biology and Endocrinology: RB&E
https://www.readbyqxmd.com/read/28041654/effects-of-dietary-soybean-isoflavones-si-on-reproduction-in-the-young-breeder-rooster
#12
Dai Heng, Tao Zhang, Ye Tian, Shangyu Yu, Wenbo Liu, Kaili Xu, Juan Liu, Yu Ding, Baochang Zhu, Yanzhou Yang, Cheng Zhang
Soybean isoflavones (SIs) are phytoestrogens that competitive with estrogens in body. Although SIs play an important role in reproduction, their role in testicular development in roosters is unknown. This study was conducted to investigate the effect of SIs on testicular development and serum reproductive hormone profiles in young breeder roosters (70-133days old). Gene expression of steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD), which are related to testosterone synthesis, in rooster testis were also evaluated after treatment with different SI doses...
February 2017: Animal Reproduction Science
https://www.readbyqxmd.com/read/28017657/direct-reprogramming-of-mouse-fibroblasts-toward-leydig-like-cells-by-defined-factors
#13
Yan Yang, Ziyi Li, Xupeng Wu, Haolin Chen, Wenting Xu, Qi Xiang, Qihao Zhang, Jie Chen, Ren-Shan Ge, Zhijian Su, Yadong Huang
Leydig cells (LCs) play crucial roles in producing testosterone, and their dysfunction leads to male hypogonadism. LC transplantation is a promising alternative therapy for male hypogonadism. However, the source of LCs limits this strategy for clinical applications. Here, we report our success in reprogramming mice fibroblasts into LCs by expressing three transcriptional factors, Dmrt1, Gata4, and Nr5a1. The induced Leydig-like cells (iLCs) expressed steroidogenic genes, had a global gene expression profile similar to that of adult LCs, and acquired androgen synthesis capabilities...
January 10, 2017: Stem Cell Reports
https://www.readbyqxmd.com/read/28008861/delayed-diagnosis-of-a-17-hydroxylase-17-20-lyase-deficient-case-presented-with-46-xy-female-low-normal-potassium-can-alert-clinician
#14
Emine Çamtosun, Zeynep Şıklar, Serdar Ceylaner, Pınar Kocaay, Merih Berberoğlu
17-hydroxylase/17,20-lyase deficiency (17OHD) is a rare autosomal recessive defect in adrenal and gonadal steroidogenesis, causes absence of secondary sexual characteristics frequently associated with hypertension and hyperkalemia. Here we report a 46, XY case, who had normal potassium levels and without hypertension. Here we present a 2,5 years old female admitted with female external genitalia and inguinal swelling. Pathology of biopsy revealed that this gonad is a testis. Karyotype was 46, XY. She had no hypertension and no hypokalemia...
December 23, 2016: Journal of Clinical Research in Pediatric Endocrinology
https://www.readbyqxmd.com/read/28002202/bh4-improves-postprandial-endothelial-function-after-a-high-fat-meal-in-men-and-postmenopausal-women
#15
Yashesh Shah, Leon Bass, Gareth W Davison, Nichole Seigler, Jennifer S Pollock, Jeff Thomas, Ryan A Harris
OBJECTIVE: The timing and duration of menopause is important when evaluating the risk for cardiovascular disease in postmenopausal women, likely related in part to nitric oxide (NO) bioavailability. The flow-mediated dilation (FMD) test is a noninvasive assessment of NO bioavailability in humans, and tetrahydrobiopterin (BH4) is essential for NO synthesis. A high-fat meal (HFM) has been used to increase lipemia and reduce NO bioavailability. Thus, this study sought to determine if menopausal transition has any impact on the postprandial endothelial function response to a HFM, and evaluate the effect of BH4 on postprandial endothelial function in postmenopausal women and men...
December 19, 2016: Menopause: the Journal of the North American Menopause Society
https://www.readbyqxmd.com/read/27993043/mechanisms-of-action-of-compounds-that-enhance-storage-lipid-accumulation-in-daphnia-magna
#16
Rita Jordão, Bruno Campos, Benjamín Piña, Romà Tauler, Amadeu M V M Soares, Carlos Barata
Accumulation of storage lipids in the crustacean Daphnia magna can be altered by a number of exogenous and endogenous compounds, like 20-hydroxyecdysone (natural ligand of the ecdysone receptor, EcR), methyl farnesoate, pyrirproxyfen (agonists of the methyl farnesoate receptor, MfR), and tributyltin (agonist of the retinoid X acid receptor, RXR). This effect, analogous to the obesogenic disruption in mammals, alters Daphnia's growth and reproductive investment. Here we propose that storage lipid accumulation in droplets is regulated in Daphnia by the interaction between the nuclear receptor heterodimer EcR:RXR and MfR...
December 20, 2016: Environmental Science & Technology
https://www.readbyqxmd.com/read/27988506/plasma-concentrations-of-osteocalcin-are-associated-with-the-timing-of-pubertal-progress-in-boys
#17
Michael M Schündeln, Lena Bäder, Cordula Kiewert, Ralf Herrmann, Dagmar Führer, Berthold P Hauffa, Corinna Grasemann
BACKGROUND: Animal models have shown that the skeletal hormone osteocalcin stimulates testicular testosterone synthesis. To assess whether osteocalcin might be a useful marker to detect pubertal development disorders, we examined osteocalcin plasma concentrations in children and adolescents with and without disorders of pubertal development. METHODS: Osteocalcin concentrations were investigated in a total of 244 patients with endocrine disorders (122 males, mean age: 11...
February 1, 2017: Journal of Pediatric Endocrinology & Metabolism: JPEM
https://www.readbyqxmd.com/read/27951541/pubertal-development-in%C3%A2-17beta-hydroxysteroid-dehydrogenase-type-3-deficiency%C3%A2
#18
Olaf Hiort, Louise Marshall, Wiebke Birnbaum, Lutz Wünsch, Paul-Martin Holterhus, Ulla Döhnert, Ralf Werner
BACKGROUND: 17β-hydroxysteroid dehydrogenase (17β-HSD) type 3 deficiency is an autosomal recessive disorder with diminished testosterone synthesis and consequently underandrogenisation. 46,XY patients with 17β-HSD type 3 deficiency are often assigned a female sex at birth but have a high virilisation potential at the time of puberty. METHODS: We studied four 46,XY patients with 17β-HSD type 3 deficiency at puberty with regard to the underlying mutations, the hormone values, and the clinical findings...
December 12, 2016: Hormone Research in Pædiatrics
https://www.readbyqxmd.com/read/27917368/sex-steroid-hormone-single-nucleotide-polymorphisms-pesticide-use-and-the-risk-of-prostate-cancer-a-nested-case-control-study-within-the-agricultural-health-study
#19
Carol H Christensen, Kathryn Hughes Barry, Gabriella Andreotti, Michael C R Alavanja, Michael B Cook, Scott P Kelly, Laurie A Burdett, Meredith Yeager, Laura E Beane Freeman, Sonja I Berndt, Stella Koutros
Experimental and epidemiologic investigations suggest that certain pesticides may alter sex steroid hormone synthesis, metabolism or regulation, and the risk of hormone-related cancers. Here, we evaluated whether single-nucleotide polymorphisms (SNPs) involved in hormone homeostasis alter the effect of pesticide exposure on prostate cancer risk. We evaluated pesticide-SNP interactions between 39 pesticides and SNPs with respect to prostate cancer among 776 cases and 1,444 controls nested in the Agricultural Health Study cohort...
2016: Frontiers in Oncology
https://www.readbyqxmd.com/read/27907900/insulin-resistance-in-polycystic-ovary-syndrome-a-systematic-review-and-meta-analysis-of-euglycaemic-hyperinsulinaemic-clamp-studies
#20
Samantha Cassar, Marie L Misso, William G Hopkins, Christopher S Shaw, Helena J Teede, Nigel K Stepto
STUDY QUESTION: What is the degree of intrinsic insulin resistance (IR) in women with polycystic ovary syndrome (PCOS) and the relative contribution of BMI to overall IR based on meta-analysis of gold standard insulin clamp studies? SUMMARY ANSWER: We report an inherent reduction (-27%) of insulin sensitivity (IS) in PCOS patients, which was independent of BMI. WHAT IS ALREADY KNOWN: PCOS is prevalent, complex and underpinned by IR but controversies surround the degree of intrinsic IR in PCOS, the effect of BMI and the impact of the different diagnostic criteria (NIH versus Rotterdam) in PCOS...
November 2016: Human Reproduction
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