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Steroid Recognition and Regulation of Hormone Action: Crystal
Research Article 799 Steroid recognition and regulation of hormone action: crystal structure of testosterone and NADP+ bound to 3a-hydroxysteroid/ dihydrodiol dehydrogenase Melanie J Bennett1†, Ross H Albert1, Joseph M Jez1, Haiching Ma2, Trevor M Penning2 and Mitchell Lewis1* Background: Mammalian 3a-hydroxysteroid dehydrogenases (3a-HSDs) Addresses: 1Department of Biochemistry and modulate the activities of steroid hormones by reversibly reducing their C3 Biophysics, The Johnson Research Foundation, 37th and Hamilton Walk, Philadelphia, PA 19104- ketone groups. In steroid target tissues, 3a-HSDs act on 5a-dihydrotestosterone, 6059, USA and 2Department of Pharmacology, a potent male sex hormone (androgen) implicated in benign prostate hyperplasia University of Pennsylvania School of Medicine, 37th and prostate cancer. Rat liver 3a-HSD belongs to the aldo-keto reductase (AKR) and Hamilton Walk, Philadelphia, PA 19104-6084, superfamily and provides a model for mammalian 3a-, 17b- and 20a-HSDs, USA. which share > 65% sequence identity. The determination of the structure of 3a- †Present address: Division of Biology, California + HSD in complex with NADP and testosterone (a competitive inhibitor) will help Institute of Technology, 1200 E California Blvd., to further our understanding of steroid recognition and hormone regulation by Pasadena, CA 91125, USA. mammalian HSDs. *Corresponding author. E-mail: [email protected] Results: We have determined the 2.5 Å resolution crystal structure of recombinant rat liver 3a-HSD complexed with NADP+ and testosterone. The Key words: aldo-keto reductase, crystal structure, structure provides the first picture of an HSD ternary complex in the AKR 3a-hydroxysteroid/dihydrodiol dehydrogenase, superfamily, and is the only structure to date of testosterone bound to a protein. -
Dehydroepiandrosterone – Is the Fountain of Youth Drying Out?
Physiol. Res. 52: 397-407, 2003 MINIREVIEW Dehydroepiandrosterone – Is the Fountain of Youth Drying Out? P. CELEC 1,2, L. STÁRKA3 1Faculty of Medicine, 2Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia and 3Institute of Endocrinology, Prague, Czech Republic Received September 15, 2002 Accepted October 7, 2002 Summary Dehydroepiandrosterone (DHEA) and its sulphate-bound form (DHEAS) are important steroids mainly of adrenal origin. Their physiological and pathophysiological functions are not yet fully identified, although a number of various possible features have been hypothesized. Most popular is the description of the “hormone of youth” as the long-term dynamics of DHEA levels are characterized by a sharp age-related decline in the late adulthood and later. Low levels of DHEA are, however, associated not only with the ageing process but also with diabetes mellitus, cardiovascular diseases and some neurological or immunological entities. In the past decade, a number of brief studies have concentrated on these relationships and also on the role of exogenous DHEA in health, disease and human well-being. This article tries to summarize some of the most important facts achieved recently. Key words Dehydroepiandrosterone • Intracrinology • Hormone replacement therapy • Steroids Introduction functions: 1) DHEA is an endogenous metabolite that cannot be patented so that pharmaceutical companies are In 1934 Butenandt and Dannenbaum isolated not interested in supporting research in this field. dehydroepiandrosterone (DHEA) from urine and in 1944 2) DHEA can be described as a “human molecule” Munson and colleagues identified its 3β-sulphate because other investigated species have much lower (DHEAS). Even now, nearly 70 years later, we still do concentrations. -
DHEA: Dehydroepiandrosterone
DHEA: Dehydroepiandrosterone Joseph Pepping, Pharm.D. [Am J Health-Syst Pharm 57(22):2048-2056, 2000. © 2000 ASHP, Inc.] Introduction Dehydroepiandrosterone (DHEA) and its active metabolite, DHEA sulfate (DHEAS), are endogenous hormones synthesized and excreted primarily by the zona reticularis of the adrenal cortex in response to adrenocorticotropic hormone. The exact mechanism of action and clinical role, if any, of DHEA and DHEAS remain unclear. Epidemiological data indicate an inverse relationship between serum DHEA and DHEAS levels and the frequency of cancer, cardiovascular disease (in men only), Alzheimer's disease and other age-related disorders, immune function, and progression of HIV infection. [1] Animal (primarily rodent) studies have suggested many beneficial effects of DHEA, including improved immune function and memory and prevention of atherosclerosis, cancer, diabetes, and obesity. Many of the benefits seen in animal studies have yet to be shown in humans. [1-3] Uses Clinically substantiated (yet still controversial) uses of DHEA include replacement therapy in patients with low serum DHEA levels secondary to chronic disease, adrenal exhaustion, or corticosteroid therapy; treating systemic lupus erythematosus (SLE), improving bone density in postmenopausal women; improving symptoms of severe depression; improving depressed mood and fatigue in patients with HIV infection; and increasing the rate of reepithelialization in patients undergoing autologous skin grafting for burns. [1,4-8] Other possible uses (with some supporting clinical studies) include enhancing the immune response and sense of well-being in the elderly, decreasing certain cardiovascular risk factors, and treating male erectile dysfunction. [4,8-12] Use of DHEA to slow or reverse the aging process, improve cognitive function, promote weight loss, increase lean muscle mass, or slow the progression of Parkinson's disease and Alzheimer's disease is clinically unsubstantiated. -
California Proposition 65 Toxicity List
STATE OF CALIFORNIA ENVIRONMENTAL PROTECTION AGENCY OFFICE OF ENVIRONMENTAL HEALTH HAZARD ASSESSMENT SAFE DRINKING WATER AND TOXIC ENFORCEMENT ACT OF 1986 CHEMICALS KNOWN TO THE STATE TO CAUSE CANCER OR REPRODUCTIVE TOXICITY 4-Mar-05 The Safe Drinking Water and Toxic Enforcement Act of 1986 requires that the Governor revise and Chemical Type of Toxicity CAS No. Date Listed A-alpha-C (2-Amino-9H-pyrido[2,3-b]indole) cancer 26148685 1-Jan-90 Acetaldehyde cancer 75070 1-Apr-88 Acetamide cancer 60355 1-Jan-90 Acetazolamide developmental 59665 20-Aug-99 Acetochlor cancer 34256821 1-Jan-89 Acetohydroxamic acid developmental 546883 1-Apr-90 2-Acetylaminofluorene cancer 53963 1-Jul-87 Acifluorfen cancer 62476599 1-Jan-90 Acrylamide cancer 79061 1-Jan-90 Acrylonitrile cancer 107131 1-Jul-87 Actinomycin D cancer 50760 1-Oct-89 Actinomycin D developmental 50760 1-Oct-92 Adriamycin (Doxorubicin hydrochloride) cancer 23214928 1-Jul-87 AF-2;[2-(2-furyl)-3-(5-nitro-2-furyl)]acrylamide cancer 3688537 1-Jul-87 Aflatoxins cancer --- 1-Jan-88 Alachlor cancer 15972608 1-Jan-89 Alcoholic beverages, when associated with alcohol abuse cancer --- 1-Jul-88 Aldrin cancer 309002 1-Jul-88 All-trans retinoic acid developmental 302794 1-Jan-89 Allyl chloride Delisted October 29, 1999 cancer 107051 1-Jan-90 Alprazolam developmental 28981977 1-Jul-90 Altretamine developmental, male 645056 20-Aug-99 Amantadine hydrochloride developmental 665667 27-Feb-01 Amikacin sulfate developmental 39831555 1-Jul-90 2-Aminoanthraquinone cancer 117793 1-Oct-89 p -Aminoazobenzene cancer -
The National Drugs List
^ ^ ^ ^ ^[ ^ The National Drugs List Of Syrian Arab Republic Sexth Edition 2006 ! " # "$ % &'() " # * +$, -. / & 0 /+12 3 4" 5 "$ . "$ 67"5,) 0 " /! !2 4? @ % 88 9 3: " # "$ ;+<=2 – G# H H2 I) – 6( – 65 : A B C "5 : , D )* . J!* HK"3 H"$ T ) 4 B K<) +$ LMA N O 3 4P<B &Q / RS ) H< C4VH /430 / 1988 V W* < C A GQ ") 4V / 1000 / C4VH /820 / 2001 V XX K<# C ,V /500 / 1992 V "!X V /946 / 2004 V Z < C V /914 / 2003 V ) < ] +$, [2 / ,) @# @ S%Q2 J"= [ &<\ @ +$ LMA 1 O \ . S X '( ^ & M_ `AB @ &' 3 4" + @ V= 4 )\ " : N " # "$ 6 ) G" 3Q + a C G /<"B d3: C K7 e , fM 4 Q b"$ " < $\ c"7: 5) G . HHH3Q J # Hg ' V"h 6< G* H5 !" # $%" & $' ,* ( )* + 2 ا اوا ادو +% 5 j 2 i1 6 B J' 6<X " 6"[ i2 "$ "< * i3 10 6 i4 11 6! ^ i5 13 6<X "!# * i6 15 7 G!, 6 - k 24"$d dl ?K V *4V h 63[46 ' i8 19 Adl 20 "( 2 i9 20 G Q) 6 i10 20 a 6 m[, 6 i11 21 ?K V $n i12 21 "% * i13 23 b+ 6 i14 23 oe C * i15 24 !, 2 6\ i16 25 C V pq * i17 26 ( S 6) 1, ++ &"r i19 3 +% 27 G 6 ""% i19 28 ^ Ks 2 i20 31 % Ks 2 i21 32 s * i22 35 " " * i23 37 "$ * i24 38 6" i25 39 V t h Gu* v!* 2 i26 39 ( 2 i27 40 B w< Ks 2 i28 40 d C &"r i29 42 "' 6 i30 42 " * i31 42 ":< * i32 5 ./ 0" -33 4 : ANAESTHETICS $ 1 2 -1 :GENERAL ANAESTHETICS AND OXYGEN 4 $1 2 2- ATRACURIUM BESYLATE DROPERIDOL ETHER FENTANYL HALOTHANE ISOFLURANE KETAMINE HCL NITROUS OXIDE OXYGEN PROPOFOL REMIFENTANIL SEVOFLURANE SUFENTANIL THIOPENTAL :LOCAL ANAESTHETICS !67$1 2 -5 AMYLEINE HCL=AMYLOCAINE ARTICAINE BENZOCAINE BUPIVACAINE CINCHOCAINE LIDOCAINE MEPIVACAINE OXETHAZAINE PRAMOXINE PRILOCAINE PREOPERATIVE MEDICATION & SEDATION FOR 9*: ;< " 2 -8 : : SHORT -TERM PROCEDURES ATROPINE DIAZEPAM INJ. -
Al Exposure Increases Proline Levels by Different Pathways in An
www.nature.com/scientificreports OPEN Al exposure increases proline levels by diferent pathways in an Al‑sensitive and an Al‑tolerant rye genotype Alexandra de Sousa1,2, Hamada AbdElgawad2,4, Fernanda Fidalgo1, Jorge Teixeira1, Manuela Matos3, Badreldin A. Hamed4, Samy Selim5, Wael N. Hozzein6, Gerrit T. S. Beemster2 & Han Asard2* Aluminium (Al) toxicity limits crop productivity, particularly at low soil pH. Proline (Pro) plays a role in protecting plants against various abiotic stresses. Using the relatively Al‑tolerant cereal rye (Secale cereale L.), we evaluated Pro metabolism in roots and shoots of two genotypes difering in Al tolerance, var. RioDeva (sensitive) and var. Beira (tolerant). Most enzyme activities and metabolites of Pro biosynthesis were analysed. Al induced increases in Pro levels in each genotype, but the mechanisms were diferent and were also diferent between roots and shoots. The Al‑tolerant genotype accumulated highest Pro levels and this stronger increase was ascribed to simultaneous activation of the ornithine (Orn)‑biosynthetic pathway and decrease in Pro oxidation. The Orn pathway was particularly enhanced in roots. Nitrate reductase (NR) activity, N levels, and N/C ratios demonstrate that N‑metabolism is less inhibited in the Al‑tolerant line. The correlation between Pro changes and diferences in Al‑sensitivity between these two genotypes, supports a role for Pro in Al tolerance. Our results suggest that diferential responses in Pro biosynthesis may be linked to N‑availability. Understanding the role of Pro in diferences between genotypes in stress responses, could be valuable in plant selection and breeding for Al resistance. Proline (Pro) is involved in a wide range of plant physiological and developmental processes1. -
Exerts Anxiolytic-Like Effects Through GABAA Receptors in a Surgical Menopause Model in Rats
Biomedicine & Pharmacotherapy 109 (2019) 2387–2395 Contents lists available at ScienceDirect Biomedicine & Pharmacotherapy journal homepage: www.elsevier.com/locate/biopha Original article Chrysin (5,7-dihydroxyflavone) exerts anxiolytic-like effects through GABAA receptors in a surgical menopause model in rats T ⁎ Juan Francisco Rodríguez-Landaa,b, , Fabiola Hernández-Lópezc, Jonathan Cueto-Escobedoa, Emma Virginia Herrera-Huertad, Eduardo Rivadeneyra-Domínguezb, Blandina Bernal-Moralesa,b, Elizabeth Romero-Avendañod a Laboratorio de Neurofarmacología, Instituto de Neuroetología, Universidad Veracruzana, Xalapa, Veracruz, Mexico b Facultad de Química Farmacéutica Biológica, Universidad Veracruzana, Xalapa, Veracruz, Mexico c Hospital General de Zona con Medicina Familiar No. 28, Delegación Veracruz Norte, Instituto Mexicano del Seguro Social (H.G.Z. c/mf. No. 28, Delegación Veracruz Norte, IMSS), Martínez de la Torre, Veracruz, Mexico d Facultad de Ciencias Químicas, Universidad Veracruzana, Orizaba, Veracruz, Mexico ARTICLE INFO ABSTRACT Keywords: The present study investigated the effects of the flavonoid chrysin (5,7-dihydroxyflavone) on anxiety-like be- Anxiolytics havior in rats in a model of surgical menopause and evaluated the participation of γ-aminobutyric acid-A Chrysin (GABAA) receptors in these actions. At 12 weeks post-ovariectomy, the effects of different doses of chrysin (0.5, GABAA 1, 2, and 4 mg/kg) were evaluated in the elevated plus maze, light/dark test, and locomotor activity test, and Oophorectomy comparisons were made with the clinically effective anxiolytic diazepam. The participation of GABA receptors Ovariectomy A in the actions of chrysin was explored by pretreating the rats with the noncompetitive GABA chloride ion Surgical menopause A channel antagonist picrotoxin (1 mg/kg). The results showed that chrysin (2 and 4 mg/kg) reduced anxiety-like behavior in both the elevated plus maze and light/dark test, and these effects were similar to diazepam. -
COMBINED LIST of Particularly Hazardous Substances
COMBINED LIST of Particularly Hazardous Substances revised 2/4/2021 IARC list 1 are Carcinogenic to humans list compiled by Hector Acuna, UCSB IARC list Group 2A Probably carcinogenic to humans IARC list Group 2B Possibly carcinogenic to humans If any of the chemicals listed below are used in your research then complete a Standard Operating Procedure (SOP) for the product as described in the Chemical Hygiene Plan. Prop 65 known to cause cancer or reproductive toxicity Material(s) not on the list does not preclude one from completing an SOP. Other extremely toxic chemicals KNOWN Carcinogens from National Toxicology Program (NTP) or other high hazards will require the development of an SOP. Red= added in 2020 or status change Reasonably Anticipated NTP EPA Haz list COMBINED LIST of Particularly Hazardous Substances CAS Source from where the material is listed. 6,9-Methano-2,4,3-benzodioxathiepin, 6,7,8,9,10,10- hexachloro-1,5,5a,6,9,9a-hexahydro-, 3-oxide Acutely Toxic Methanimidamide, N,N-dimethyl-N'-[2-methyl-4-[[(methylamino)carbonyl]oxy]phenyl]- Acutely Toxic 1-(2-Chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (Methyl-CCNU) Prop 65 KNOWN Carcinogens NTP 1-(2-Chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) IARC list Group 2A Reasonably Anticipated NTP 1-(2-Chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) (Lomustine) Prop 65 1-(o-Chlorophenyl)thiourea Acutely Toxic 1,1,1,2-Tetrachloroethane IARC list Group 2B 1,1,2,2-Tetrachloroethane Prop 65 IARC list Group 2B 1,1-Dichloro-2,2-bis(p -chloropheny)ethylene (DDE) Prop 65 1,1-Dichloroethane -
AHFS Pharmacologic-Therapeutic Classification System
AHFS Pharmacologic-Therapeutic Classification System Abacavir 48:24 - Mucolytic Agents - 382638 8:18.08.20 - HIV Nucleoside and Nucleotide Reverse Acitretin 84:92 - Skin and Mucous Membrane Agents, Abaloparatide 68:24.08 - Parathyroid Agents - 317036 Aclidinium Abatacept 12:08.08 - Antimuscarinics/Antispasmodics - 313022 92:36 - Disease-modifying Antirheumatic Drugs - Acrivastine 92:20 - Immunomodulatory Agents - 306003 4:08 - Second Generation Antihistamines - 394040 Abciximab 48:04.08 - Second Generation Antihistamines - 394040 20:12.18 - Platelet-aggregation Inhibitors - 395014 Acyclovir Abemaciclib 8:18.32 - Nucleosides and Nucleotides - 381045 10:00 - Antineoplastic Agents - 317058 84:04.06 - Antivirals - 381036 Abiraterone Adalimumab; -adaz 10:00 - Antineoplastic Agents - 311027 92:36 - Disease-modifying Antirheumatic Drugs - AbobotulinumtoxinA 56:92 - GI Drugs, Miscellaneous - 302046 92:20 - Immunomodulatory Agents - 302046 92:92 - Other Miscellaneous Therapeutic Agents - 12:20.92 - Skeletal Muscle Relaxants, Miscellaneous - Adapalene 84:92 - Skin and Mucous Membrane Agents, Acalabrutinib 10:00 - Antineoplastic Agents - 317059 Adefovir Acamprosate 8:18.32 - Nucleosides and Nucleotides - 302036 28:92 - Central Nervous System Agents, Adenosine 24:04.04.24 - Class IV Antiarrhythmics - 304010 Acarbose Adenovirus Vaccine Live Oral 68:20.02 - alpha-Glucosidase Inhibitors - 396015 80:12 - Vaccines - 315016 Acebutolol Ado-Trastuzumab 24:24 - beta-Adrenergic Blocking Agents - 387003 10:00 - Antineoplastic Agents - 313041 12:16.08.08 - Selective -
Triclosan Disrupts Thyroid Hormones: Mode-Of-Action, Developmental Susceptibility, and Determination of Human Relevance
Triclosan Disrupts Thyroid Hormones: Mode-of-Action, Developmental Susceptibility, and Determination of Human Relevance Katie Beth Paul “A dissertation submitted to the faculty of the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Curriculum of Toxicology.” Chapel Hill 2011 Approved by: Kim L. R. Brouwer, Pharm.D., Ph.D. Kevin M. Crofton, Ph.D. Michael J. DeVito, Ph.D. Philip C. Smith, Ph.D James A. Swenberg, D.V.M., Ph.D. ©2011 Katie Beth Paul ALL RIGHTS RESERVED ii Abstract Katie Beth Paul Triclosan Disrupts Thyroid Hormones: Mode-of-Action, Developmental Susceptibility, and Determination of Human Relevance (Under the direction of Kevin M. Crofton, Ph.D.) Preliminary study demonstrated that triclosan (TCS), a bacteriostat in myriad consumer products, decreases serum thyroxine (T4) in rats. Adverse neurodevelopmental consequences result from thyroid hormone (TH) disruption; therefore determination of whether TCS disrupts THs during development, its mode-of-action (MOA), and the human relevance is critical. This research tested the hypothesis that TCS disrupts THs via activation of pregnane X and constitutive androstane receptors (PXR, CAR), mediating Phase I-II enzyme and hepatic transporter expression and protein changes, thereby increasing catabolism and elimination of THs, resulting in decreased TH concentrations. For Aim One, the hypothesized MOA was assessed using weanling female Long-Evans rats orally exposed to TCS (0-1000 mg/kg/day) for four days. Serum T4 decreased 35% at 300 mg/kg/day. Activity and expression of markers of Phase I (Cyp2b, Cyp3a1) and Phase II (Ugt1a1, Sult1c1) metabolism were moderately induced, consistent with PXR and/or CAR activation and increased hepatic catabolism. -
Reproductive DHEA-S
Reproductive DHEA-S Analyte Information - 1 - DHEA-S Introduction DHEA-S, DHEA sulfate or dehydroepiandrosterone sulfate, it is a metabolite of dehydroepiandrosterone (DHEA) resulting from the addition of a sulfate group. It is the sulfate form of aromatic C19 steroid with 10,13-dimethyl, 3-hydroxy group and 17-ketone. Its chemical name is 3β-hydroxy-5-androsten-17-one sulfate, its summary formula is C19H28O5S and its molecular weight (Mr) is 368.5 Da. The structural formula of DHEA-S is shown in (Fig.1). Fig.1: Structural formula of DHEA-S Other names used for DHEA-S include: Dehydroisoandrosterone sulfate, (3beta)-3- (sulfooxy), androst-5-en-17-one, 3beta-hydroxy-androst-5-en-17-one hydrogen sulfate, Prasterone sulfate and so on. As DHEA-S is very closely connected with DHEA, both hormones are mentioned together in the following text. Biosynthesis DHEA-S is the major C19 steroid and is a precursor in testosterone and estrogen biosynthesis. DHEA-S originates almost exclusively in the zona reticularis of the adrenal cortex (Fig.2). Some may be produced by the testes, none is produced by the ovaries. The adrenal gland is the sole source of this steroid in women, whereas in men the testes secrete 5% of DHEA-S and 10 – 20% of DHEA. The production of DHEA-S and DHEA is regulated by adrenocorticotropin (ACTH). Corticotropin-releasing hormone (CRH) and, to a lesser extent, arginine vasopressin (AVP) stimulate the release of adrenocorticotropin (ACTH) from the anterior pituitary gland (Fig.3). In turn, ACTH stimulates the adrenal cortex to secrete DHEA and DHEA-S, in addition to cortisol. -
Prediction of Premature Termination Codon Suppressing Compounds for Treatment of Duchenne Muscular Dystrophy Using Machine Learning
Prediction of Premature Termination Codon Suppressing Compounds for Treatment of Duchenne Muscular Dystrophy using Machine Learning Kate Wang et al. Supplemental Table S1. Drugs selected by Pharmacophore-based, ML-based and DL- based search in the FDA-approved drugs database Pharmacophore WEKA TF 1-Palmitoyl-2-oleoyl-sn-glycero-3- 5-O-phosphono-alpha-D- (phospho-rac-(1-glycerol)) ribofuranosyl diphosphate Acarbose Amikacin Acetylcarnitine Acetarsol Arbutamine Acetylcholine Adenosine Aldehydo-N-Acetyl-D- Benserazide Acyclovir Glucosamine Bisoprolol Adefovir dipivoxil Alendronic acid Brivudine Alfentanil Alginic acid Cefamandole Alitretinoin alpha-Arbutin Cefdinir Azithromycin Amikacin Cefixime Balsalazide Amiloride Cefonicid Bethanechol Arbutin Ceforanide Bicalutamide Ascorbic acid calcium salt Cefotetan Calcium glubionate Auranofin Ceftibuten Cangrelor Azacitidine Ceftolozane Capecitabine Benserazide Cerivastatin Carbamoylcholine Besifloxacin Chlortetracycline Carisoprodol beta-L-fructofuranose Cilastatin Chlorobutanol Bictegravir Citicoline Cidofovir Bismuth subgallate Cladribine Clodronic acid Bleomycin Clarithromycin Colistimethate Bortezomib Clindamycin Cyclandelate Bromotheophylline Clofarabine Dexpanthenol Calcium threonate Cromoglicic acid Edoxudine Capecitabine Demeclocycline Elbasvir Capreomycin Diaminopropanol tetraacetic acid Erdosteine Carbidopa Diazolidinylurea Ethchlorvynol Carbocisteine Dibekacin Ethinamate Carboplatin Dinoprostone Famotidine Cefotetan Dipyridamole Fidaxomicin Chlormerodrin Doripenem Flavin adenine dinucleotide