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https://www.readbyqxmd.com/read/28337175/effects-of-chronic-acth-excess-on-human-adrenal-cortex
#1
REVIEW
Xavier Bertagna
Chronic ACTH excess leads to chronic cortisol excess, without escape phenomenon, resulting in Cushing's syndrome. Excess adrenal androgens also occur: in females, they will overcompensate the gonadotrophic loss, inducing high testosterone; in males, they will not compensate it, inducing low testosterone. Chronic ACTH excess leads to chronic adrenal mineralocorticoid excess and low aldosterone levels: after an acute rise, aldosterone plasma levels resume low values after a few days when ACTH is prolonged. Two other mineralocorticoids in man, cortisol and 11 deoxycorticosterone (DOC), at the zona fasciculata, will not escape the long-term effect of chronic ACTH excess and their secretion rates will remain elevated in parallel...
2017: Frontiers in Endocrinology
https://www.readbyqxmd.com/read/28333286/high-prevalence-of-moderate-and-severe-depressive-and-anxiety-symptoms-in-polycystic-ovary-syndrome-a-systematic-review-and-meta-analysis
#2
Laura G Cooney, Iris Lee, Mary D Sammel, Anuja Dokras
Study question: Do women with polycystic ovary syndrome (PCOS) have an increased prevalence of moderate and severe depressive and anxiety symptoms compared with control women, and do these symptoms correlate with age, BMI, testosterone, hirsutism or insulin resistance (IR)? Summary answer: Women with PCOS have significantly increased odds of moderate and severe depressive and anxiety symptoms, independent of obesity, and the symptoms are weakly associated with age, BMI, elevated testosterone, hirsutism and IR...
March 9, 2017: Human Reproduction
https://www.readbyqxmd.com/read/28324044/inverse-regulation-of-dht-synthesis-enzymes-5%C3%AE-reductase-types-1-and-2-by-the-androgen-receptor-in-prostate-cancer
#3
Étienne Audet-Walsh, Tracey Yee, Ingrid S Tam, Vincent Giguère
5α-reductase types 1 and 2, encoded by SRD5A1 and SRD5A2, are the two enzymes that can catalyze the conversion of testosterone to dihydrotestosterone, the most potent androgen receptor (AR) agonist in prostate cells. 5α-reductase type 2 is the predominant isoform expressed in the normal prostate. However, its expression decreases during prostate cancer (PCa) progression, while SRD5A1 increases and the mechanism underlying this transcriptional regulatory switch is still unknown. Interrogation of SRD5A mRNA expression in three publicly available datasets confirmed that SRD5A1 is increased in primary and metastatic PCa compared to non-tumoral prostate tissues, while SRD5A2 is decreased...
January 23, 2017: Endocrinology
https://www.readbyqxmd.com/read/28323036/targeting-androgen-receptor-versus-targeting-androgens-to-suppress-castration-resistant-prostate-cancer
#4
Changcheng Guo, Shuyuan Yeh, Yuanjie Niu, Gonghui Li, Junhua Zheng, Lei Li, Chawnshang Chang
Prostate cancer (PCa) is the 2nd leading cause of cancer-related death among men in the United States and its progression is tightly associated with the androgen/androgen receptor (AR) signals. Men castrated before puberty (eunuchs) or men with inherited deficiency of type II 5α-reductase (with failure to convert testosterone to the more potent dihydrotestosterone) (DHT) do not develop PCa. To date, androgen deprivation therapy (ADT) with anti-androgen treatments to reduce or prevent androgens from binding to the AR remains the main therapeutic option for advanced PCa since its discovery by Huggins and Hodges in 1941...
March 18, 2017: Cancer Letters
https://www.readbyqxmd.com/read/28280794/the-putative-effects-of-d-aspartic-acid-on-blood-testosterone-levels-a-systematic-review
#5
REVIEW
Farzad Roshanzamir, Seyyed Morteza Safavi
BACKGROUND: D-Aspartic acid (D-Asp) is in invertebrate and vertebrate neuroendocrine tissues, where it carries out important physiological functions. Recently, it has been reported that D-Asp is involved in the synthesis and release of testosterone and is assumed can be used as a testosterone booster for infertile men, and by athletes to increase muscle mass and strength. OBJECTIVE: The aim of this review is to summarize available evidence related to the effects of D-Asp on serum testosterone levels...
January 2017: International Journal of Reproductive Biomedicine (Yazd, Iran)
https://www.readbyqxmd.com/read/28274349/sex-hormones-and-acne
#6
Qiang Ju, Tao Tao, Tingting Hu, Ayşe Serap Karadağ, Safaa Al-Khuzaei, WenChieh Chen
The skin is an endocrine organ with the expression of metabolizing enzymes and hormone receptors for diverse hormones. The sebaceous gland is the main site of hormone biosynthesis, especially for androgens, and acne is the classical androgen-mediated dermatosis. In sebocytes, conversion of 17-hydroxyprogesterone directly to dihydrotestosterone bypassing testosterone has been demonstrated, while type II 17β-hydroxysteroid dehydrogenase can inactivate the action of testosterone and dihydrotestosterone. The androgen receptor-dependent genomic effect of dihydrotestosterone on sebocytes is confirmed...
March 2017: Clinics in Dermatology
https://www.readbyqxmd.com/read/28267564/development-of-17%C3%AE-hydroxysteroid-dehydrogenase-type-3-as-a-target-in-hormone-dependent-prostate-cancer-therapy
#7
REVIEW
Xiaohui Ning, Yan Yang, Hong Deng, Qihao Zhang, Yadong Huang, Zhijian Su, Yongmei Fu, Qi Xiang, Shu Zhang
17β-Hydroxysteroid dehydrogenase type 3 (17β-HSD3) is expressed almost exclusively in the testes and specifically converts the weak androgenic androstenedione to active testosterone (T) in the presence of NADPH. Additionally, studies have demonstrated that 17β-HSD3 is over-expressed in hormone-dependent prostate cancer. T, which interacts with the androgen receptor (AR), eventually stimulates the growth of prostate cancer cells. Defects in T synthesis or action impair the development of the male phenotype during embryogenesis and cause the autosomal recessive disorder male pseudohermaphroditism...
March 4, 2017: Steroids
https://www.readbyqxmd.com/read/28262723/developmental-sex-differences-in-the-metabolism-of-cardiolipin-in-mouse-cerebral-cortex-mitochondria
#8
Estefanía Acaz-Fonseca, Ana Ortiz-Rodriguez, Ana B Lopez-Rodriguez, Luis M Garcia-Segura, Mariana Astiz
Cardiolipin (CL) is a mitochondrial-specific phospholipid. CL content and acyl chain composition are crucial for energy production. Given that estradiol induces CL synthesis in neurons, we aimed to assess CL metabolism in the cerebral cortex (CC) of male and female mice during early postnatal life, when sex steroids induce sex-dimorphic maturation of the brain. Despite the fact that total amount of CL was similar, its fatty acid composition differed between males and females at birth. In males, CL was more mature (lower saturation ratio) and the expression of the enzymes involved in synthetic and remodeling pathways was higher, compared to females...
March 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28257863/effects-of-selenium-on-the-proliferation-apoptosis-and-testosterone-production-of-sheep-leydig-cells-in%C3%A2-vitro
#9
Lei Shi, Ruigao Song, Xiaolei Yao, Youshe Ren
The objective of this study was to investigate the effects of selenium (Se) on in vitro proliferation, apoptosis and testosterone production of sheep Leydig cells and its underlying mechanism. Leydig cells were collected from 8-month-old sheep and divided into four treatment groups (0, 2.0, 4.0 and 8.0 μmol/L Se). After treatment with Se for 48 h, the MTT and flow cytometric assay were used to detect cell proliferation and apoptosis. Testosterone level in the culture medium was determined by ELISA. The mRNA expression and protein abundance of cell cycle, apoptosis and testosterone synthesis-related genes were detected using real-time PCR and western blot analysis...
April 15, 2017: Theriogenology
https://www.readbyqxmd.com/read/28240622/oxandrolone-coadministration-does-not-alter-plasma-propranolol-concentrations-in-severely-burned-pediatric-patients
#10
Ashley N Guillory, David N Herndon, Michael B Silva, Clark R Andersen, Oscar E Suman, Celeste C Finnerty
The systemic impact of severe burn injury results in a variety of disorders that require therapeutic intervention. Propranolol, a nonselective β1, β2-adrenergic receptor antagonist, reduces resting heart rate and cardiac work caused by elevated circulating catecholamines. Oxandrolone, a testosterone mimetic, promotes protein synthesis and anabolism to counter muscle wasting. Coadministration of these drugs is expected to synergistically improve patient outcomes. Testosterone administration is known to alter β-adrenergic receptor-mediated signaling...
February 23, 2017: Journal of Burn Care & Research: Official Publication of the American Burn Association
https://www.readbyqxmd.com/read/28212445/long-term-effects-of-fetal-undernutrition-on-rat-heart-role-of-hypertension-and-oxidative-stress
#11
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
#12
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
#13
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
#14
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, corticosteroids, 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
#15
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
#16
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
#17
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...
April 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28122810/testosterone-prevents-protein-loss-via-the-hepatic-urea-cycle-in-human
#18
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)...
April 2017: European Journal of Endocrinology
https://www.readbyqxmd.com/read/28103392/a-peroxygenase-from-chaetomium-globosum-catalyzes-the-selective-oxygenation-of-testosterone
#19
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. We investigated a cell-free approach to incorporate epoxy and hydroxyl functionalities directly into the bulky molecule testosterone by a novel unspecific peroxygenase (UPO) that is produced by the ascomycetous fungus Chaetomium globosum in a complex medium rich in carbon and nitrogen. Purification by fast protein liquid chromatography revealed two enzyme fractions with the same molecular mass (36 kDa) and with specific activity of 4...
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
#20
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
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