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19 nor testosterone derivatives

Mayel Chirinos, Marta Durand, María Elena González-González, Gabriela Hernández-Silva, Israel Maldonado-Rosas, Pablo Lopez, Fernando Larrea
Levonorgestrel (LNG), a synthetic 19 nor-testosterone derivative, is widely used for emergency contraception. It is well known that LNG prevents ovulation only when given prior to the surge of serum luteinizing hormone (LH) during the periovulatory phase of the menstrual cycle. This observation suggests that LNG, given its contraceptive efficacy, has additional effects other than those affecting ovulation. In this study, we have evaluated the effects on human sperm functionality of uterine flushings (UF) obtained from women at day LH+1 of a control cycle (CTR-LH+1) and after receiving LNG (LNG-LH+1) two days before the surge of LH...
September 8, 2017: Reproduction: the Official Journal of the Society for the Study of Fertility
Francesco P Busardò, Paola Frati, Mariantonia Di Sanzo, Simona Napoletano, Enrica Pinchi, Simona Zaami, Vittorio Fineschi
Nandrolone is included in the class II of anabolic androgenic steroids (AAS) which is composed of 19-nor-testosterone-derivates. In general, AAS is a broad and rapidly increasing group of synthetic androgens used both clinically and illicitly. AAS in general and nandrolone decanoate (ND) in particular have been associated with several behavioral disorders. The purpose of this review is to summarize the literature concerning studies dealing with ND exposure on animal models, mostly rats that mimic human abuse systems (i...
January 2015: Current Neuropharmacology
Z H Mohamed, Nawal A El-Koussi, Nadia M Mahfouz, Adel F Youssef, Gehad A Abdel Jaleel, Samia A Shouman
The progestational potency and selectivity of synthetic steroidal agonists can be enhanced by even larger chemical moieties at 17α-position of the steroid backbones. Hereby a series 5a-c and 6a-c of novel 17α-[1-(substituted phenyl)-1,2,3-triazol-4-yl]-19-nortestosterone-17β-yl acetates were designed and synthesized using click chemistry approach searching progestogenic derivatives with potential anticancer activity. Compounds 5a,b and 6a,c have affected to different extents the three histopatho-logical parameters considered for evaluation of their progestational activity...
June 5, 2015: European Journal of Medicinal Chemistry
Qian Cheng, Christal D Sohl, Francis K Yoshimoto, F Peter Guengerich
Dihydrotestosterone is a more potent androgen than testosterone and plays an important role in endocrine function. We demonstrated that, like testosterone, dihydrotestosterone can be oxidized by human cytochrome P450 (P450) 19A1, the steroid aromatase. The products identified include the 19-hydroxy- and 19-oxo derivatives and the resulting Δ(1,10)-, Δ(5,10)-, and Δ(9,10)-dehydro 19-norsteroid products (loss of 19-methyl group). The overall catalytic efficiency of oxidation was ~10-fold higher than reported for 3α-reduction by 3α-hydroxysteroid dehydrogenase, the major enzyme known to deactivate dihydrotestosterone...
August 24, 2012: Journal of Biological Chemistry
Rocío García-Becerra, David Ordaz-Rosado, Gabriela Noé, Bertha Chávez, Austin J Cooney, Fernando Larrea
7α-methyl-19-nortestosterone (MENT) is an androgen with potent gonadotropin inhibitory activity and prostate-sparing effects. These attributes give MENT advantages over testosterone as a male contraceptive, but, as in the case of testosterone, a partial dose-dependent suppression of spermatogenesis has been observed. Combination of testosterone or MENT with synthetic progestins improves the rate of azoospermia; however, it is unknown whether these combinations affect hormone androgenicity or exert synergistic effects via progestational or androgenic interaction...
February 2012: Reproduction: the Official Journal of the Society for the Study of Fertility
Yoanna María Alvarez-Ginarte, Luis Alberto Montero-Cabrera, José Manuel García de la Vega, Pedro Noheda-Marín, Yovani Marrero-Ponce, José Alberto Ruíz-García
Quantitative structure-activity relationship (QSAR) study of 19-nor-testosterone steroids family was performed using quantum and physicochemical molecular descriptors. The quantum-chemical descriptors were calculated using semiempirical calculations. The descriptor values were statistically correlated using multi-linear regression analysis. The QSAR study indicated that the electronic properties of these derivatives have significant relationship with observed biological activities. The found QSAR equations explain that the energy difference between the LUMO and HOMO, the total dipole moment, the chemical potential and the value of the net charge of different carbon atoms in the steroid nucleus showed key interaction of these steroids with their anabolic-androgenic receptor binding site...
August 2011: Journal of Steroid Biochemistry and Molecular Biology
U Gaspard, A Pintiaux, F Kridelka
In combined oral contraception (OC), a drastic reduction of both ethinylestradiol and androgenic progestins mostly derived from 19 NOR testosterone, allowed to moderately reduce the adverse impact of classical combined pills on metabolism and circulation (both arterial and venous). However, the marked hepatic action of ethinylestradiol, even in small dosages, lessens the expected risk reduction. For the first time, an OC has been developed, which contains estradiol valerate (with reduced hepatic action because of lack of a 17alpha ethinyl group) with dienogest, a 19 NOR testosterone-derived nonandrogenic progestin, which powerfully inhibits endometrial proliferation...
December 2010: Revue Médicale de Liège
Kjersti Bakken, Agnès Fournier, Eiliv Lund, Marit Waaseth, Vanessa Dumeaux, Françoise Clavel-Chapelon, Alban Fabre, Bertrand Hémon, Sabina Rinaldi, Véronique Chajes, Nadia Slimani, Naomi E Allen, Gillian K Reeves, Sheila Bingham, Kay-Tee Khaw, Anja Olsen, Anne Tjønneland, Laudina Rodriguez, Maria-José Sánchez, Pilar Amiano Etxezarreta, Eva Ardanaz, Maria-José Tormo, Petra H Peeters, Carla H van Gils, Annika Steffen, Mandy Schulz, Jenny Chang-Claude, Rudolf Kaaks, Rosario Tumino, Valentina Gallo, Teresa Norat, Elio Riboli, Salvatore Panico, Giovanna Masala, Carlos A González, Franco Berrino
Menopausal hormone therapy (MHT) is characterized by use of different constituents, regimens and routes of administration. We investigated the association between the use of different types of MHT and breast cancer risk in the EPIC cohort study. The analysis is based on data from 133,744 postmenopausal women. Approximately 133,744 postmenopausal women contributed to this analysis. Information on MHT was derived from country-specific self-administered questionnaires with a single baseline assessment. Incident breast cancers were identified through population cancer registries or by active follow-up (mean: 8...
January 1, 2011: International Journal of Cancer. Journal International du Cancer
Sergio A Moreno, Anita Shyam, Abraham Morgentaler
INTRODUCTION: The most widely used method for measuring free testosterone (FT) is by analog immunoassay (aFT); however, this assay has been criticized as unreliable based on laboratory studies in small groups of men. Calculated FT (cFT), derived from total testosterone (TT) and sex-hormone binding globulin (SHBG) values has been recommended in its place. There are limited data comparing aFT and cFT in clinical populations. AIM: The purpose of this study was to compare aFT with cFT in a population of ambulatory men in a clinical setting...
May 2010: Journal of Sexual Medicine
Valeri V Mossine, Pankaj Chopra, Thomas P Mawhinney
Prior investigations on the beneficial effect of dietary processed tomato products and lycopene on prostate cancer risk suggested that lycopene may require the presence of other constituents to exert its chemopreventive potential. We investigated whether ketosamines, a group of carbohydrate derivatives present in dehydrated tomato products, may interact with lycopene against prostate tumorigenesis. One ketosamine, FruHis, strongly synergized with lycopene against proliferation of the highly metastatic rat prostate adenocarcinoma MAT-LyLu cell line in vitro...
June 1, 2008: Cancer Research
J Isenberg, A Prokop, E Skouras
Derivatives of testosterone or of 19-nor-testosterone are used as anabolics for the purpose of improving performance although the effect of anabolics is known still to be under discussion. The use of anabolic steroids continues among competitive athletes despite increased controls and increasingly frequent dramatic incidents connected with them. Whereas metabolic dysfunction during anabolic use is well documented, ruptures of the large tendons are rarely reported. Within 18 months, a 29-year-old professional footballer needed surgery for rupture of the patellar tendon and of both Achilles tendons...
January 2008: Der Unfallchirurg
J Shields-Botella, I Duc, E Duranti, F Puccio, P Bonnet, R Delansorne, J Paris
The specific pharmacological profile of the 19-norprogestin nomegestrol acetate (NOMAC) is, at least in part, defined by its pattern of binding affinities to the different steroid hormone receptors. In the present study, its affinity to the progesterone receptor (PgR), the androgen receptor (AR) and the estrogen receptor (ER) was re-evaluated and compared to those obtained for progesterone (P) and several progestins. The characteristics of binding to the PgR in rat uterus were determined and Ki were found to be roughly similar with 22...
November 2003: Journal of Steroid Biochemistry and Molecular Biology
1. The University of California Medical Center at San Francisco is participating in a nationwide cooperative study attempting to improve hormonal therapy of disseminated breast cancer. A prospective protocol is followed in which the antitumor efficacy of an investigational compound is compared with that of a reference standard of known efficacy. Known variables (menopausal age and site of most significant metastasis) are randomized to distribute similar patients into experimental and control groups. Assignment of the therapeutic agent is made at random to avoid bias, and where feasible, neither patient nor investigator knows which compound is given...
April 1963: California Medicine
Rocio García-Becerra, Elizabeth Borja-Cacho, Austin J Cooney, Kathy J Jackson, Ana E Lemus, Gregorio Pérez-Palacios, Fernando Larrea
Levonorgestrel (LNG), a 19-nor-testosterone derivative, is widely used in contraceptive formulations. This compound does not bind to the estrogen receptor (ER), but it shows estrogen-like effects under in vivo and in vitro conditions. The estrogenicity of LNG may be attributed to its bio-transformation into non-phenolic metabolites. In this study, the ability of A-ring reduced LNG metabolites to activate transcription via an estrogenic mechanism of action, including differences between ER alpha and ER beta subtypes, were investigated...
November 2002: Journal of Steroid Biochemistry and Molecular Biology
I S Fraser
Progestogens may have profound effects on lipid metabolism. Effects are generally dose-related and are more pronounced with 19-nor testosterone derivatives. Progestogens suppress circulating levels of high-density lipoprotein cholesterol (HDL-C) and increase circulating low-density lipoprotein cholesterol. Therefore, over a long period of time, the risk of atherosclerosis may increase. Although contraceptive use of depot medroxyprogesterone acetate (DMPA) reduced HDL-C levels by 15-20%, the levels generally remain within the normal range...
January 1983: Contraceptive Delivery Systems
R A Lobo
There are multiple metabolic pathways for progesterone. Progestogens are metabolized differently as compared with the fate of endogenous progesterone, and the metabolites are significantly dependent upon the route of administration and the physiologic and pathologic state of the patient. Marked variations between patients have also been observed. Many organs metabolize progestogens, each in its own way. In turn, the metabolites each have different biologic potencies, which include major effects on the central nervous system...
February 1999: Journal of Reproductive Medicine
C Campagnoli, N Biglia, C Cantamessa, L Lesca, P Sismondi
Epidemiological and biological data on HRT and breast cancer risk are reviewed. Some aspects deserve consideration. (1) The majority of epidemiological data have been gathered from populations where high estrogen doses (> or = 1.25 mg daily of conjugated estrogens) were used as first line therapy. (2) HRT does not increase the risk in overweight women, even in the series in which a risk increase (in longterm users) is found. This could be as a result of the fact that oral estrogens, through their metabolic and hepatocellular effects, reverse some biological features of obesity (e...
December 15, 1999: Maturitas
C A Mendoza-Rodríguez, I Camacho-Arroyo, G A García, M A Cerbón
It has been suggested that some contraceptive derivatives of 19-nor-testosterone possess estrogenic activity that may facilitate the development of breast cancer. The aim of this work was to investigate the estrogenic properties of norethisterone (NET) and its A-ring-reduced derivatives by determining progesterone receptor (PR) and c-fos mRNA content of two estrogen-regulated genes in the uterus of ovariectomized rats. mRNA content was evaluated by Northern blot 1-6 h after 17 beta-estradiol administration...
May 1999: Contraception
V P Uralets, P A Gillette
Since the appearance of 4-androsten-3,17-dione (I) as a nutritional supplement in early 1997, we have frequently observed a characteristic deterioration of endogenous steroid profiles in athletes' urine in routine anabolic steroid testing in which concentrations of major endogenous urinary steroids and testosterone exceed normal. Human excretion studies are performed with I and newer, over-the-counter "supplements" 4-androsten-3beta,17beta-diol (II) and 19-nor-4-androsten-3,17-dione (III). Endogenous urinary steroids affected by I and II are androsterone, etiocholanolone, their hydroxylated derivatives 5alpha- and 5beta-androstan-3alpha,17beta-diols, testosterone, and epitestosterone...
September 1999: Journal of Analytical Toxicology
R Palatsi, A Ruokonen, A Oikarinen
Isotretinoin, used to treat severe acne, has been shown to induce hormonal changes, especially to reduce 5 alpha-reductase in the production of the tissue-derived dihydrotestosterone (DHT) metabolite 3 alpha-Adiol G. However, the effects of isotretinoin on other pituitary, adrenal or gonadal hormones have not been thoroughly elucidated. In the present study, isotretinoin administered at a dose of 0.5 mg/kg/day for 4 weeks caused no marked changes in the serum levels of pituitary, adrenal or gonadal hormones or 3 alpha-Adiol G in patients with severe papulopustulotic acne (n = 19)...
September 1997: Acta Dermato-venereologica
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