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https://www.readbyqxmd.com/read/28814452/medical-ovariectomy-in-menopausal-breast-cancer-patients-with-high-testosterone-levels
#1
Giorgio Secreto, Paola Muti, Milena Sant, Elisabetta Meneghini, Vittorio Krogh
Five years of adjuvant therapy with anti-estrogens reduce the incidence of disease progression by about 50% in estrogen receptor-positive breast cancer patients, but late relapse can still occur after that anti-estrogens have been discontinued. In these patients, excessive androgen production may account for renewed excessive estrogen formation and increased risk of late relapse. In the 50% of patients who do not benefit with anti-estrogens, the effect of therapy is limited by de novo or acquired resistance to treatment...
August 16, 2017: Endocrine-related Cancer
https://www.readbyqxmd.com/read/28811197/seasonal-changes-in-plasma-testosterone-and-cortisol-suggest-an-androgen-mediated-regulation-of-the-pituitary-adrenal-axis-in-the-tarabul-s-gerbil-gerbillus-tarabuli-thomas-1902
#2
Yamina Zatra, Naouel Aknoun-Sail, Arezki Kheddache, Abdelouafi Benmouloud, Salima Charallah, Elara N Moudilou, Jean-Marie Exbrayat, Farida Khammar, Zaina Amirat
In the desert gerbil Gerbillus tarabuli (Thomas, 1902), cortisol is the main glucocorticosteroid produced by the adrenal glands. Plasma cortisol concentrations show highest values when testosterone is reduced and lowest values during the breeding season which occurs from early winter to late spring. In order to specify the implication of testicular androgens in these corticosteroid seasonal variations we investigated the effects induced by gonadectomy performed during the breeding season on the pituitary adrenal axis...
August 12, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28797804/a-game-of-two-gene-expression-analysis-of-brain-cyp19a1b-and-gonadal-cyp19a1a-aromatase-in-females-of-a-neotropical-cichlid-fish-through-the-parental-care-period-and-removal-of-the-offspring
#3
Martín R Ramallo, Renato M Honji, Agustina Birba, Leonel Morandini, María L Varela, Griselda Genovese, Renata G Moreira, Gustavo M Somoza, Matías Pandolfi
For many species parental behavior is essential for the survival of the offspring. While the ultimate causes of teleost parental behavior have been widely studied, comparatively little is known about its proximate causes. The aim of this study was to analyze the yet unexplored, potential dual role of brain and gonadal aromatases, the enzymes responsible for the conversion of androgens to estrogens in the brains and gonads of teleosts, respectively, on the different stages of the maternal care period of the biparental cichlid Cichlasoma dimerus, locally known as chanchita...
August 7, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28796631/endocrine-disruption-in-human-fetal-testis-explants-by-individual-and-combined-exposures-to-selected-pharmaceuticals-pesticides-and-environmental-pollutants
#4
Pierre Gaudriault, Séverine Mazaud-Guittot, Vincent Lavoué, Isabelle Coiffec, Laurianne Lesné, Nathalie Dejucq-Rainsford, Martin Scholze, Andreas Kortenkamp, Bernard Jégou
BACKGROUND: Numerous chemicals are capable of disrupting androgen production, but the possibility that they might act together to produce effects greater than those of the most effective component in the mixture has not been studied directly in human tissues. Suppression of androgen synthesis in fetal life has been associated with testis maldescent, malformations of the genitalia at birth, and poor semen quality later in life. OBJECTIVES: Our aim was to investigate whether chemicals can act together to disrupt androgen production in human fetal testis explants and to evaluate the importance of mixture effects when characterizing the hazard of individual chemicals...
August 4, 2017: Environmental Health Perspectives
https://www.readbyqxmd.com/read/28789926/commentary-on-redirecting-abiraterone-metabolism-to-fine-tune-prostate-cancer-anti-androgen-therapy-li-z-alyamani-m-li-j-rogacki-k-abazeed-m-upadhyay-sk-balk-sp-taplin-me-auchus-rj-sharifi-n-nature-2016-may-25-533-7604-547-51
#5
Byron H Lee
Abiraterone blocks androgen synthesis and prolongs survival in patients with castration-resistant prostate cancer, which is otherwise driven by intratumoral androgen synthesis. Abiraterone is metabolized in patients to Δ(4)-abiraterone (D4A), which has even greater antitumour activity and is structurally similar to endogenous steroidal 5α-reductase substrates, such as testosterone. Here, we show that D4A is converted to at least three 5α-reduced and three 5β-reduced metabolites in human serum. The initial 5α-reduced metabolite, 3-keto-5α-abiraterone, is present at higher concentrations than D4A in patients with prostate cancer taking abiraterone, and is an androgen receptor agonist, which promotes prostate cancer progression...
August 5, 2017: Urologic Oncology
https://www.readbyqxmd.com/read/28771887/acsl3-promotes-intratumoral-steroidogenesis-in-prostate-cancer-cells
#6
Toshiro Migita, Ken-Ichi Takayama, Tomohiko Urano, Daisuke Obinata, Kazutaka Ikeda, Tomoyoshi Soga, Satoru Takahashi, Satoshi Inoue
Long-chain acyl-coenzyme A (CoA) synthetase 3 (ACSL3) is an androgen-responsive gene involved in the generation of fatty acyl-CoA esters. ACSL3 is expressed in both androgen-sensitive and castration-resistant prostate cancer (CRPC). However, its role in prostate cancer remains elusive. We overexpressed ACSL3 in androgen-dependent LNCaP cells and examined the downstream effectors of ACSL3. Furthermore, we examined the role of ACSL3 in the androgen metabolism of prostate cancer. ACSL3 overexpression led to upregulation of several genes such as aldo-keto reductase 1C3 (AKR1C3) involved in steroidogenesis, which utilizes adrenal androgen dehydroepiandrosterone sulfate (DHEAS) as substrate, and downregulated androgen-inactivating enzyme UDP-glucuronosyltransferase 2 (UGT2B)...
August 3, 2017: Cancer Science
https://www.readbyqxmd.com/read/28770686/body-composition-changes-with-testosterone-replacement-therapy-following-spinal-cord-injury-and-aging-a-mini-review
#7
Tom E Nightingale, Pamela Moore, Joshua Harman, Refka Khalil, Ranjodh S Gill, Teodoro Castillo, Robert A Adler, Ashraf S Gorgey
Context Hypogonadism is a male clinical condition in which the body does not produce enough testosterone. Testosterone plays a key role in maintaining body composition, bone mineral density, sexual function, mood, erythropoiesis, cognition and quality of life. Hypogonadism can occur due to several underlying pathologies during aging and in men with physical disabilities, such as spinal cord injury (SCI). This condition is often under diagnosed and as a result, symptoms undertreated. Methods In this mini-review, we propose that testosterone replacement therapy (TRT) may be a viable strategy to improve lean body mass (LBM) and fat mass (FM) in men with SCI...
August 3, 2017: Journal of Spinal Cord Medicine
https://www.readbyqxmd.com/read/28752572/effect-of-paracetamol-on-semen-quality
#8
REVIEW
S A Banihani
Several published studies, both direct and indirect, have connected paracetamol, also named acetaminophen, a commonly used over-the-counter analgesic and antipyretic medication, with semen quality and male infertility, although as yet this connection is unclear. This review addresses the effect of paracetamol on semen quality and hence on male factor infertility. We searched the MEDLINE database from January 1980 through January 2017 for English-language articles using the key words "paracetamol" and "acetaminophen" versus "sperm...
July 28, 2017: Andrologia
https://www.readbyqxmd.com/read/28739284/-%C3%A2-%C3%A2-%C3%A2-role-of-5%C3%AE-dihydrotestosterone-in-testicular-development-of-gilthead-seabream-following-finasteride-administration
#9
M García-García, M Sánchez-Hernández, M P García-Hernández, A García-Ayala, E Chaves-Pozo
In teleosts, spermatogenesis is regulated by pituitary gonadotropins and sex steroids. 5α-dihydrotestosterone (DHT), derived from testosterone (T) through the action of 5α-reductase, has recently been suggested to play a physiologically important role in some fish species. In this study, gilthead seabream, Sparus aurata L., males received an implant of 1μgT/g body mass (bm) or vehicle alone and, 7days later, 1mg finasteride (FIN, an inhibitor of 5α-reductase)/kg bm or vehicle. Serum levels of T, 11-ketotestosterone (11KT), DHT and 17β-estradiol (E2), and the mRNA levels of the main enzymes involved in their synthesis, were analysed...
July 21, 2017: Journal of Steroid Biochemistry and Molecular Biology
https://www.readbyqxmd.com/read/28708508/developmental-changes-in-the-histological-structure-of-the-testes-and-testosterone-profiles-in-male-guinea-fowls-numida-meleagris
#10
Iddriss I Abdul-Rahman, Frederick Y Obese, Ian A Jeffcoate
Owing to the paucity of information on the reproductive biology of guinea fowls, a study involving a total of 66 males was conducted, and documented the developmental changes in histological structure of the testes of guinea cocks from hatching until adulthood. Changes in testosterone synthesis during sexual development were also determined. Age-related changes were analysed using univariate analysis for completely randomised design and means separated using Tukey's test/Kruskal-Wallis test and medians separated by Mann-Whitney U test...
June 23, 2017: Theriogenology
https://www.readbyqxmd.com/read/28705778/maternal-linuron-exposure-alters-testicular-development-in-male-offspring-rats-at-the-whole-genome-level
#11
Jianwei Bai, Hua Han, Feng Wang, Liyu Su, Hongwei Ding, Xiyin Hu, Binli Hu, Hong Li, Wei Zheng, Yan Li
Linuron is a widely used herbicide; its toxicity on the male reproductive system has been recognized. The current study was designed to explore the molecular mechanism underlying linuron-induced reproductive toxicity. Pregnant rats received daily oral gavage of linuron at the dose of 120mg/kg/d from gestation day (GD)12 to GD17. Tissues from male offspring rats were collected for pathological examination and microarray gene expression profiling. Changes in gene expression were further verified by quantitative real-time RT-PCR...
July 11, 2017: Toxicology
https://www.readbyqxmd.com/read/28704441/a-comparison-of-sex-steroid-concentration-levels-in-the-vitreous-and-serum-of-patients-with-vitreoretinal-diseases
#12
Yuko Nishikawa, Seita Morishita, Taeko Horie, Masanori Fukumoto, Takaki Sato, Teruyo Kida, Hidehiro Oku, Jun Sugasawa, Tsunehiko Ikeda, Kimitoshi Nakamura
The purpose of this study was to compare steroid hormone concentration levels in the vitreous and serum of vitreoretinal disease patients to elucidate the possibility of neurosteroid production in the retina. Serum and vitreous samples were collected from vitrectomy patients, and estradiol (E2) and testosterone (T) concentrations were measured using electro-chemiluminescence immunoassay. We measured E2 in epiretinal membrane (ERM, n = 14), macular hole (MH, n = 18), proliferative diabetic retinopathy (PDR, n = 20), and retinal detachment (RD, n = 19) cases, and T in ERM (n = 14), MH (n = 17), PDR (n = 13), and RD (n = 17) cases...
2017: PloS One
https://www.readbyqxmd.com/read/28703914/hsd3b2-associated-in-modulating-steroid-hormone-synthesis-pathway-regulates-the-differentiation-of-chicken-embryonic-stem-cells-into-spermatogonial-stem-cells
#13
Chen Zhang, Man Wang, Nana He, Mahmoud F Ahmed, Yilin Wang, Ruifeng Zhao, Xinjian Yu, Jing Jin, Jiuzhou Song, Qisheng Zuo, Yani Zhang, Bichun Li
Steroid hormones regulate differentiation of various types of cell during embryogenesis. Testosterone is one of the androgens that bind to receptors to regulate gene expression and promote spermatogenesis. Our results showed that testosterone, as a product of steroid hormones synthesis pathway, could facilitate the differentiation of embryonic stem cells (ESCs) into spermatogonial stem cells (SSCs). The analysis of the steroid hormones synthesis pathway demonstrated that 3beta-hydroxysteroid dehydrogenase2 (Hsd3b2) plays a major role in the synthesis of testosterone...
July 13, 2017: Journal of Cellular Biochemistry
https://www.readbyqxmd.com/read/28700985/genes-involved-in-long-term-memory-are-expressed-in-testis-of-cryptorchid-boys-and-respond-to-gnrha-treatment
#14
Faruk Hadziselimovic, Katharina Gegenschatz-Schmid, Gilvydas Verkauskas, Philippe Demougin, Vytautas Bilius, Darius Dasevicius, Michael B Stadler
It has been known for many years that boys with unilateral or bilateral undescended testis (cryptorchidism) tend to have a low IQ, and those who belong to the high infertility risk (HIR) group perform less well at school than low infertility risk (LIR) patients. However, the molecular biological processes underlying this phenomenon are not understood. In this study, we report the outcome of testicular RNA profiling for genes involved in long-term memory formation. We analyzed the histology and the transcriptome of testicular biopsies from bilateral HIR cryptorchid boys, comparing those who received GnRHa treatment for 6 months after the first surgery with those who did not receive GnRHa before the second surgery...
2017: Cytogenetic and Genome Research
https://www.readbyqxmd.com/read/28686079/experimental-manipulation-of-corticosterone-does-not-influence-the-clearance-rate-of-plasma-testosterone-in-birds
#15
Pierre Deviche, Stève Desaivre, Mathieu Giraudeau
In vertebrates, exposure to acute stressors stimulates the secretion of adrenal glucocorticoids such as corticosterone, and in some situations this hormone plays an important role in orchestrating the trade-off that exists between reproduction and self-maintenance. Stressful conditions often lead to a decrease in plasma levels of sex steroids such as testosterone in males, and it has been hypothesized that corticosterone contributes to this decrease. Generally supporting this proposition, glucocorticoids can inhibit the reproductive axis activity at multiple levels, including direct effects on testicular endocrine function...
September 2017: Physiological and Biochemical Zoology: PBZ
https://www.readbyqxmd.com/read/28685147/genotyping-the-high-altitude-mestizo-ecuadorian-population-affected-with-prostate-cancer
#16
REVIEW
Andrés López-Cortés, Alejandro Cabrera-Andrade, Carolina Salazar-Ruales, Ana Karina Zambrano, Santiago Guerrero, Patricia Guevara, Paola E Leone, César Paz-Y-Miño
Prostate cancer (PC) is the second most commonly diagnosed type of cancer in males with 1,114,072 new cases in 2015. The MTHFR enzyme acts in the folate metabolism, which is essential in methylation and synthesis of nucleic acids. MTHFR C677T alters homocysteine levels and folate assimilation associated with DNA damage. Androgens play essential roles in prostate growth. The SRD5A2 enzyme metabolizes testosterone and the V89L polymorphism reduces in vivo SRD5A2 activity. The androgen receptor gene codes for a three-domain protein that contains two polymorphic trinucleotide repeats (CAG, GGC)...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28683411/synthesis-of-novel-%C3%AE-cyclodextrin-functionalized-s-n-codoped-carbon-dots-for-selective-detection-of-testosterone
#17
Mai Luo, Yifan Hua, Yiran Liang, Jiajun Han, Donghui Liu, Wenting Zhao, Peng Wang
A novel functionalized carbon dot has been synthesized by covalently linking β-cyclodextrin to the surface of N, S codoped carbon dots (β-CD-CDs). The characterization was confirmed by transmission electron microscopy, X-ray photoelectron spectroscopy, infrared spectra, ultraviolet-visible, and fluorescence emission spectra. On the basis of this carbon dot and (ferrocenylmethyl) trimethylammonium iodide (Fc(+)), a photo-induced electron transfer (PET) fluorescent probe system was developed to determine the concentration of testosterone in water and identify testosterone in cell by fluorescence imaging as a visible biomarker...
June 27, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/28679622/extra-ovarian-gonadotropin-negative-feedback-revealed-by-aromatase-inhibition-in-female-marmoset-monkeys
#18
Marissa Kraynak, Matthew T Flowers, Robert A Shapiro, Amita Kapoor, Jon Levine, David H Abbott
While the ovary produces the majority of estradiol (E2) in mature female primates, extra-ovarian sources contribute to E2 synthesis and action, including brain E2 regulating hypothalamic gonadotropin-releasing hormone (GnRH). In ovary-intact female rodent models, aromatase inhibition (AI) induces a PCOS-like hypergonadotropic hyperandrogenism due to absent E2-mediated negative feedback. In order to examine the role of extra-ovarian E2 on nonhuman primate gonadotropin regulation, the present study employs letrozole to elicit AI in adult female marmoset monkeys...
July 5, 2017: American Journal of Physiology. Endocrinology and Metabolism
https://www.readbyqxmd.com/read/28667465/the-role-of-vitamin-d-in-male-fertility-a-focus-on-the-testis
#19
REVIEW
Cristina de Angelis, Mariano Galdiero, Claudia Pivonello, Francesco Garifalos, Davide Menafra, Federica Cariati, Ciro Salzano, Giacomo Galdiero, Mariangela Piscopo, Alfonso Vece, Annamaria Colao, Rosario Pivonello
In the last decade, vitamin D has emerged as a pleiotropic molecule with a multitude of autocrine, paracrine and endocrine functions, mediated by classical genomic as well as non-classical non-genomic actions, on multiple target organs and systems. The expression of vitamin D receptor and vitamin D metabolizing enzymes in male reproductive system, particularly in the testis, suggests the occurrence of vitamin D synthesis and regulation as well as function in the testis. The role of vitamin D in the modulation of testis functions, including hormone production and spermatogenesis, has been investigated in animals and humans...
September 2017: Reviews in Endocrine & Metabolic Disorders
https://www.readbyqxmd.com/read/28660243/effects-of-selective-deletion-of-tyrosine-hydroxylase-from-kisspeptin-cells-on-puberty-and-reproduction-in-male-and-female-mice
#20
Shannon B Z Stephens, Melvin L Rouse, Kristen P Tolson, Reanna B Liaw, Ruby A Parra, Navi Chahal, Alexander S Kauffman
The neuropeptide kisspeptin, encoded by Kiss1, regulates reproduction by stimulating GnRH secretion. Kiss1-syntheizing neurons reside primarily in the hypothalamic anteroventral periventricular (AVPV/PeN) and arcuate (ARC) nuclei. AVPV/PeN Kiss1 neurons are sexually dimorphic, with females expressing more Kiss1 than males, and participate in estradiol (E2)-induced positive feedback control of GnRH secretion. In mice, most AVPV/PeN Kiss1 cells coexpress tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine synthesis (in this case, dopamine)...
May 2017: ENeuro
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