DOCSLIB.ORG

On the Mode of Action of Selenium Sulfide

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
On the Mode of Action of Selenium Sulfide View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector PRELIMINARY AND SHORT REPORTS ON THE MODE OF ACTION OF SELENIUM SIJLFIDE* PETER FLE5CE, M.D., PH.D. Although selenium sulfide shampoo (Selsun®) is widely used in the treatment of dan- druff and seborrhea, the mode of action of selenium sulfide is unknown. The literature on this subject is contradictory. The fact has been stressed that locally applied selenium sulfide in Selsun has no toxic effect. In support of this assumption it has been pointed out that after use of the shampoo the urinary selenium levels were in the normal range (1). This argument does not carry much weight, because in well-established cases of selenium poi- soning the urinary selenium levels were often normal (2, 3). It has been also claimed that the action of selenium was related to that of sulfur on account of its proximity to this element in the periodic table (1, 4). However, the pharmacologic actions of selenium re- semble more closely those of arsenic (5). Finally, the possibility has been also suggested that the effect of selenium sulfide was essentially due to the sulfur released from this combination (6). One definitely established fact about selenium compounds in general is their ability to inactivate free sulfhydryl groups and compounds through mercaptide formation, in the same way as arsenic. This sulfhydryl inactivating effect has been demonstrated in vitro with sulfhydryl compounds (7) and enzymes (8, 9), and in vivo by protecting animals poi- soned with selenium salts by the administration of glutathione (10) or BAL (11). In order to test whether or not selenium sulfide had a similar sulfhydryl inhibitory effect as other selenium salts, various tissues were incubated with selenium sulfide suspensions and their sulfhydryl content determined. EXPERIMENTAL The following tissues were used for in vitro studies: 1. Powdered epidermal keratin from scales of a patient with psoriatic exfoliative dermatitis. 2. Ten per cent aqueous mouse liver homogenates. 3. Ten per cent aqueous homogenates of human epidermis, separated with the stretch method (12). The selenium sulfide suspensions and the controls employed were as follows: 1. Selsun® (2.5% selenium disulfide shampoo) and a Selsun placebot which presumably had the same composition as Selsun, except for a lower selenium sulfide content (0.1%), both diluted 5timeswith water. 2. Two per cent Duponol C (sodium lauryl sulfate) with 0.5% selenium disulfide suspended and 2% Duponol as control. 3. An aqueous suspen- sion of selenium disulfide with water as control. Incubation ranged from 10 to 60 minutes and was carried out at room temperature, 40°C and (in the case of keratin) in a boiling water bath. Sulfhydryl was determined with Bennett's reagent (13). REsULTS There was a significant and consistent inhibition of free sulfhydryl groups when mouse liver and human epidermis were incubated with the selenium disulfide-detergent suspen- sions (Table I). No consistent effect on epidermal keratin was found. *Fromthe Department of Dermatology (Donald M. Pillsbury, M.D., Director) Uni- versity of Pennsylvania School of Medicine. This study was supported by U.S.P.H.S. Grant G-36O1. Received for publication July 13, 1953. f Obtained through courtesy of Abbott Laboratories. 233 234 THE JOURNAL OF INVESTIGATIVE DERMATOLOGY DISCUSSION These experiments bring proof that selenium sulfide has a definite chemical action. The finding that under our experimental conditions Selsun had relatively little inhibitory effect on the sulfhydryl groups of human epidermis does not necessarily mean that this shampoo is relatively inert, because the placebo which served as its control also contained selenium sulfide, although in a 25 times smaller concentration. The actual concentrations, however, give no information about the amounts of ionized (active) selenium in solution. Therefore, the truly significant experiment is the one in which Duponol, containing selenium sulfide, was compared with Duponol itself. In this experiment it was conclusively shown that selenium sulfide inactivated the sulfhydryl groups of human epidermal homogenates under experimental conditions (10 minutes at 40°C) similar to those encountered during the actual therapeutic use of Selsun Shampoo. The combination of a detergent with a sulfhydryl inhibitor gives rise to an interesting chain of reactions. Detergents, as recently shown by Van Scott and Lyon, increase the amount of reactive sulfhydryl groups in epidermal keratins, presumably by exposing formerly masked sulfhydryl groups (14). By such a process of denaturation, detergents TABLE I Inactivation of free sulfhydryl with selenium sulfide-detergent suspensions INCUBATION TISSV PREPARATION nmtarrioN Mouse liver (10 mg) 0.5% SeS2 in Duponol (0.5 ml) 1 hour 80% 10 mm. 51% Selsun 5X diluted (0.5 nil) 1 hour 69% 10 mm. 44% Human epidermis 0.5% SeS2 in Duponol (0.5 ml) 10 mm. 21% (10 mg) Selsun 5X diluted (0.5 ml) 10 mm. 5% similarly affect other proteins (15), including those of the epidermis (16). Thus the effect of a selenium sulfide shampoo is twofold: on the one hand, the detergent releases previously non-reactive sulfhydryl groups and the selenium compounds then inactivate some of these groups. On the basis of the present study, it is not permissible to speculate whether or not this double action is responsible for the therapeutic effect of Selsun. It is of interest to point out that selenium-containing waters have been used by Napoleon for the treatment of "diseases of keratinization" among his troops (17). Disorganized and inhibited processes of keratinization are also prominent symptoms of selenium poisoning in cattle (7, 17, 18). SUMMARY Selenium clisulfide in vitro inactivates the free sulfhydryl groups of human epidermis and mouse liver. The effect of Selsun shampoo is twofold: due to its detergent action it makes available previously non-reactive sulfhydryl groups, some of which then are in- activated by selenium disulfide. REFERENCES 1. SLINGER, W. N. AND HUBBARD, D. M.: Treatment of seborrheic dermatitis with a shampoo containing selenium disulfide. Arch. Dermat. & Syph., 64: 41—48, 1951. 2. HALTER, K.: Die Selenvergiftung unter besonderer Berücksichtigung der dabei beo- bacliteten Hautveranderungen in Verbindung mit sekundärer Porphyrie. Arch. f. Dermat. u. Syph., 178: 340—57, 1938. ACTION OF SELENIUM SULFIDE 235 3.LEMLEY, R. E.: Selenium poisoning in the human. J. Lancet, 60: 528—31, 1940. 4. SLEPYAN, A. H.: Selenium disulfide suspension in treatment of seborrheic dermatitis of the scalp. Arch. Dermat. & Syph., 65: 228—29, 1952. 5. SOLLMANN, T.: A manual of pharmacology. 7th Edition. W. B. Saunders Co., Phil- adelphia, 1948. 6. Personal communication to the author. 7. Moxor., A. L. AND RHIAN, M.: Selenium poisoning. Physiol. Rev., 23:305—37,1943. 8. SMITH, M. I.: Chronic endemic selenium poisoning. A review of the more recent field and laboratory studies. J.A.M.A., 116: 512-6, 1941. 9. BAREON, E. S. €1. AND KALNITSKY, G.: Inhibition of succinic oxidase by heavy metals and its reactivation with dithiols. Biochem. J., 41: 346—51, 1947. 10. PAINTER, E. P.: The chemistry and toxicity of selenium compounds with special refer- ence to the selenium problem. Chem. Rev., 28: 169—213, 1941. 11. Bmooisy, J. B. AND SLAUGHTER, D.: Administration of BAL in selenium poisoning. Proc. Soc. Exper. Biol. & Med., 72: 196—8, 1949. 12. VAN SCOTT, E. J.: Mechanical separation of the epidermis from the corium. J. Invest. Dermat., 18: 377—9, 1952. 13. FLESCH, P. AND KUN, E.: A colorimetric method for determination of sulfhydryl groups in tissue homogenates by 1-(4 chloromercuriphenylazo)-naphthol-2. Proc. Soc. Exper. Biol. & Med., 74: 249—51, 1950. 14. VAN SCOTT, E. J. AND LYON, J. B.: A chemical measure of the effect of soaps and deter- gents on the skin. To be published. 15. AN80N, M. L.: The sulfhydryl groups of egg albumin. J. Gen. Physiol., 24: 399—421, 1941. 16. VAN ScoUr, E. J. AND FLE5CE, P.: To be published. 17. TABOURY, F.: Toxicologie du sélénium et de ses composes chez les animaux et les vege- taux. Bull. Soc. chim. biol., 27: 157—63, 1945. 18. SMITH, M. I.: Studies in chronic selenosis. I. The chronic toxicity of naturally occurring food selenium. Nat. Inst. Health Bull., 174: 1—13, 1940..
Load more

Recommended publications
  • Differential Effects of Tranylcypromine and Imidazole on Mammary Carcinogenesis in Rats Fed Low and High Fat Diets1
    [CANCER RESEARCH 49, 3168-3172, June 15, 1989] Differential Effects of Tranylcypromine and Imidazole on Mammary Carcinogenesis in Rats Fed Low and High Fat Diets1 David L. McCormick,2 Ann M. Spicer, and Jacqueline L. Hollister Life Sciences Department, IIT Research Institute, Chicago, Illinois 60616 ABSTRACT studies with this class of compounds used inhibitors of the cyclooxygenase pathway of arachidonic acid catabolism; exper Neoplastic development in the rat mammary gland can be suppressed iments performed in our laboratory and by Ip and coworkers by inhibition of the activity of several enzymes involved in eicosanoid biosynthesis. In order to investigate the potential utility of prostacyclin demonstrated that the postcarcinogen phase of rat mammary and thromboxane synthetases as targets for mammary cancer chemopre- carcinogenesis can be suppressed by dietary administration of vention, experiments were conducted to determine the influence of tran- indomethacin (7, 8) or flurbiprofen (9). However, although the ylcypromine (TCP), an inhibitor of prostacyclin synthetase, and ¡mida/ole anticarcinogenic activity of indomethacin is similar to that of (IMI), an inhibitor of thromboxane synthetase, on mammary carcinogen- more widely studied inhibitors of mammary carcinogenesis such esis induced in rats by 7V-methyl-/V-nitrosourea. Fifty-day-old female as retinyl acetate (10) and selenium (11), the dose levels of Sprague-Dawley |Hsd:SD(BR)l rats received a single s.c. dose of 0 or 40 indomethacin required for chemopreventive efficacy in rats are mg of .V-mcth>l-.Y-nitrosoiirea per kg of body weight. Beginning 7 days close to the threshold of lethal toxicity (12). For this reason, after carcinogen administration, groups of rats were fed isoenergetic, studies are ongoing to identify additional modifiers of arachi casein-based diets containing 3 or 20% corn oil (w/w), supplemented with donic acid metabolism whose administration provides an effec (per kg of diet) 10 mg of TCP, 1000 mg of IMI, or sucrose carrier only.
    [Show full text]
  • Curative Effect of Selenium Against Indomethacin-Induced Gastric Ulcers in Rats
    J. Microbiol. Biotechnol. (2011), 21(4), 400–404 doi: 10.4014/jmb.1012.12019 First published online 19 January 2011 Curative Effect of Selenium Against Indomethacin-Induced Gastric Ulcers in Rats Kim, Jeong-Hwan1, Byung-Woo Kim1,3,4, Hyun-Ju Kwon1,3,4, and Soo-Wan Nam1,2,4* 1Department of Biomaterial Control, 2Department of Biotechnology and Bioengineering, 3Department of Life Science and Biotechnology, and 4Blue-Bio Industry RIC, Dong-Eui University, Busan 614-714, Korea Received: December 16, 2010 / Revised: December 30, 2010 / Accepted: December 31, 2010 Indomethacin is a nonsteroid anti-inflammatory agent erosions, ulcerative lesions, and petechial bleeding in the that is known to induce severe gastric mucosal lesions. In mucosa of stomach as serious side effects [10, 18]. According this study, we investigated the effect of selenium on gastric to previous reports, the oral administration of indomethacin in mucosal lesions in rats. To confirm the curative effect of rats causes ulcerative lesions in the gastric mucosa [7, 13]. selenium against indomethacin-induced gastric ulcers, Furthermore, the development of the gastric mucosal lesions gastric ulcers were induced by oral administration of induced by indomethacin is mainly mediated through 25 mg/kg indomethacin, and then different doses (10, 50, generation of oxygen free radicals and lipid peroxidation and 100 µg/kg of body weight) of selenium or vehicle were [6, 22, 25, 26, 28, 29]. treated by oral gavage for 3 days. Oral administration of Selenium is an essential nutrient of fundamental importance indomethacin clearly increased the gastric ulcer area in to human biology. It has important metabolic functions in the stomach, whereas selenium applied for 3 days significantly animals, including protection of membrane lipids and decreased the gastric ulcer area in a dose-dependent macromolecules from oxidative damage produced by peroxides manner.
    [Show full text]
  • Potential Adverse Effects of Resveratrol: a Literature Review
    International Journal of Molecular Sciences Review Potential Adverse Effects of Resveratrol: A Literature Review Abdullah Shaito 1 , Anna Maria Posadino 2, Nadin Younes 3, Hiba Hasan 4 , Sarah Halabi 5, Dalal Alhababi 3, Anjud Al-Mohannadi 3, Wael M Abdel-Rahman 6 , Ali H. Eid 7,*, Gheyath K. Nasrallah 3,* and Gianfranco Pintus 6,2,* 1 Department of Biological and Chemical Sciences, Lebanese International University, 1105 Beirut, Lebanon; [email protected] 2 Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; [email protected] 3 Department of Biomedical Science, College of Health Sciences, and Biomedical Research Center Qatar University, P.O Box 2713 Doha, Qatar; [email protected] (N.Y.); [email protected] (D.A.); [email protected] (A.A.-M.) 4 Institute of Anatomy and Cell Biology, Justus-Liebig-University Giessen, 35392 Giessen, Germany; [email protected] 5 Biology Department, Faculty of Arts and Sciences, American University of Beirut, 1105 Beirut, Lebanon; [email protected] 6 Department of Medical Laboratory Sciences, College of Health Sciences and Sharjah Institute for Medical Research, University of Sharjah, Sharjah P.O Box: 27272, United Arab Emirates; [email protected] 7 Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236 Beirut, Lebanon * Correspondence: [email protected] (A.H.E.); [email protected] (G.K.N.); [email protected] (G.P.) Received: 13 December 2019; Accepted: 15 March 2020; Published: 18 March 2020 Abstract: Due to its health benefits, resveratrol (RE) is one of the most researched natural polyphenols.
    [Show full text]
  • Common Name: SELENIUM SULFIDE HAZARD SUMMARY
    Common Name: SELENIUM SULFIDE CAS Number: 7446-34-6 RTK Substance number: 1653 DOT Number: UN 2657 Date: October 1995 Revision: October 2001 ------------------------------------------------------------------------- ------------------------------------------------------------------------- HAZARD SUMMARY * Selenium Sulfide can affect you when breathed in and by * If you think you are experiencing any work-related health passing through your skin. problems, see a doctor trained to recognize occupational * Selenium Sulfide should be handled as a CARCINOGEN- diseases. Take this Fact Sheet with you. -WITH EXTREME CAUTION. * Contact can irritate the eyes with possible eye damage. WORKPLACE EXPOSURE LIMITS * Breathing Selenium Sulfide can irritate the nose and The following exposure limits are for Selenium compounds throat. (measured as Selenium): * High exposure may cause headache, nausea, vomiting, garlic odor of the breath, metallic taste and coated tongue. OSHA: The legal airborne permissible exposure limit * Repeated exposure can cause pallor, nervousness and (PEL) is 0.2 mg/m3 averaged over an 8-hour mood changes. workshift. * Selenium Sulfide may damage the liver and kidneys. NIOSH: The recommended airborne exposure limit is IDENTIFICATION 0.2 mg/m3 averaged over a 10-hour workshift. Selenium Sulfide is a bright orange powder. It is used in medicated shampoos. ACGIH: The recommended airborne exposure limit is 3 0.2 mg/m averaged over an 8-hour workshift. REASON FOR CITATION * Selenium Sulfide is on the Hazardous Substance List * Selenium Sulfide may be a CARCINOGEN in humans. because it is regulated by OSHA and cited by ACGIH, There may be no safe level of exposure to a carcinogen, so DOT, NIOSH, NTP, DEP, HHAG and EPA. all contact should be reduced to the lowest possible level.
    [Show full text]
  • Role of Selenium in HIV Infection
    Role of selenium in HIV infection The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Stone, Cosby A, Kosuke Kawai, Roland Kupka, and Wafaie W Fawzi. 2010. “Role of Selenium in HIV Infection.” Nutrition Reviews 68 (11) (October 20): 671–681. doi:10.1111/j.1753-4887.2010.00337.x. Published Version doi:10.1111/j.1753-4887.2010.00337.x Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:26951080 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA NIH Public Access Author Manuscript Nutr Rev. Author manuscript; available in PMC 2011 November 1. NIH-PA Author ManuscriptPublished NIH-PA Author Manuscript in final edited NIH-PA Author Manuscript form as: Nutr Rev. 2010 November ; 68(11): 671±681. doi:10.1111/j.1753-4887.2010.00337.x. The Role of Selenium in HIV Infection Cosby A Stone, Kosuke Kawai, Roland Kupka, Wafaie W Fawzi Harvard School of Public Health Cosby A Stone, School of Public Health and School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA Kosuke Kawai, Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA Roland Kupka, and Department of Nutrition, Harvard School of Public Health, Boston, MA, USA and United Nations Children’s Fund, Regional Office for West and Central Africa, Dakar, Senegal Wafaie W.
    [Show full text]
  • Hepatotoxicity-Induced by the Therapeutic Dose of Acetaminophen and the Ameliorative Effect of Oral Co-Administration of Selenium/ Tribulus Terrestris Extract in Rats
    Int. J. Morphol., 38(5):1444-1454, 2020. Hepatotoxicity-Induced by the Therapeutic Dose of Acetaminophen and the Ameliorative Effect of Oral Co-administration of Selenium/ Tribulus terrestris Extract in Rats Hepatotoxicidad Inducida por la Dosis Terapéutica de Acetaminofén y el Efecto de Mejora de la Administración Conjunta de Extracto de Selenio Tribulus terrestris en Ratas Amin A. Al-Doaiss1,2 AL-DOAISS, A. A. Hepatotoxicity-induced by the therapeutic dose of acetaminophen and the ameliorative effect of oral co-administration of selenium / Tribulus terrestris extract in rats. Int. J. Morphol., 38(5):1444-1454, 2020. SUMMARY: Over dose or long-term clinical use of therapeutic doses of acetaminophen (APAP) causes hepatotoxicity. Various strategies attempted to ameliorate APAP-hepatotoxicity have been found to be unsuitable for clinical practice. This study was aimed to illustrate the histopathological changes induced by therapeutic dose of APAP and investigate the hepatoprotective role of oral co- administration of selenium/ Tribulus terrestris (TT) extract concurrently against hepatotoxicity induced by APAP in rats. Fifty-four healthy male albino Wistar rats were randomized into nine groups (G1–G9) of six rats each, and administered with APAP and TT orally for 30 days as follows: Control (2ml normal saline), APAP (470 mg/kg), APAP (470 mg/kg) + selenium (2 mg/kg), APAP (470 mg/kg) + TT (98 mg/kg), APAP (470 mg/kg) + selenium (2mg/kg) + TT (98 mg/kg), APAP (470 mg/kg) + silymarin (200 mg/kg), selenium (2 mg/ kg), TT (98 mg/kg) and silymarin (200 mg/kg) groups. The results demonstrated that exposure of rats to therapeutic dose of APAP for 30 days caused significant histopathological changes parallel to elevated blood chemistry parameters.
    [Show full text]
  • HYPERFORIN PROMOTES MITOCHONDRIAL FUNCTION and DEVELOPMENT of OLIGODENDROCYTES a Thesis Submitted to the College of Graduate
    HYPERFORIN PROMOTES MITOCHONDRIAL FUNCTION AND DEVELOPMENT OF OLIGODENDROCYTES A Thesis Submitted to the College of Graduate Studies and Research in Partial Fulfillment of the Requirements for a Master’s Degree in the Department of Psychiatry University of Saskatchewan Saskatoon By Yanlin Wang © Copyright Yanlin Wang, December 2009. All rights reserved. PERMISSION TO USE In presenting this thesis in partial fulfillment of the requirements for a Master’s degree from the University of Saskatchewan, I agree that the Libraries of this University may make it freely available for inspection. I further agree that permission for copying of this thesis in any manner, in whole or in part, for scholarly purposes may be granted by the professor or professors who supervised my thesis work or, in their absence, by the Head of the Department or the Dean of the College in which my thesis work was done. It is understood that any copying or publication or use of this thesis or parts thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of Saskatchewan in any scholarly use which may be made of any material in my thesis. Requests for permission to copy or to make other use of material in this thesis in whole or part should be addressed to: Head, the Department of Psychiatry University of Saskatchewan Saskatoon, Saskatchewan Canada, S7N 5E4 i ABSTRACT Major depressive disorder is a common severe psychiatric disorder with unknown etiology. Recent studies show that the loss and malfunction of oligodendrocytes are closely related to the neuropathological changes in depression, which can be reversed by antidepressant treatment.
    [Show full text]
  • Expression of Enzymes Associated with Prostaglandin Synthesis in Equine Conceptuses
    animals Article Expression of Enzymes Associated with Prostaglandin Synthesis in Equine Conceptuses Sven Budik 1,*, Ingrid Walter 2,3, Marie-Christine Leitner 1, Reinhard Ertl 3 and Christine Aurich 1 1 Platform for Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; [email protected] (M.-C.L.); [email protected] (C.A.) 2 Department of Pathobiology, Institute of Anatomy, Histology and Embryology, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; [email protected] 3 VetCore Facility for Research, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; [email protected] * Correspondence: [email protected]; Tel.: +43-125-077-6403 Simple Summary: The mobile preimplantative phase of equine gestation, taking place between day 9 and 16 after ovulation, is characterized by peristaltic contractions of the uterus caused by secretion of prostaglandins by the spheric equine conceptus. This mobility is necessary for maternal recognition of pregnancy in equids, taking place around day 14 after ovulation. The presented study investigated the spatial and temporal abundance of prostaglandin synthesis enzymes of the equine conceptus, elucidating a basal and an inducible system for prostaglandin E2. Prostaglandin F2α synthesis is restricted to the “periembryonic”pole area and relies on enzymatic conversion of prostaglandin E2. This scenario led to a model able to explain the embryonic forward motion driven by the peristaltic contractions of the uterus. In vitro incubation of primary trophoblast cell cultures with oxytocin showed no influence of this hormone on prostaglandin synthesis. Citation: Budik, S.; Walter, I.; Leitner, M.-C.; Ertl, R.; Aurich, C.
    [Show full text]
  • Alteration of Prostaglandin Production and Agonist Responsiveness by N-6 Polyunsaturated Fatty Acids in Endometrial Cells from Late-Gestation Ewes
    249 Alteration of prostaglandin production and agonist responsiveness by n-6 polyunsaturated fatty acids in endometrial cells from late-gestation ewes Z Cheng, M Elmes, S E Kirkup,DREAbayasekara and D C Wathes Reproduction and Development Group, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herts AL9 7TA, UK (Requests for offprints should be addressed to D C Wathes; Email [email protected]) Abstract We investigated the effect of n-6 polyunsaturated fatty alterations in responsiveness as a result of PUFA treatment. acids (PUFAs) on prostaglandin (PG) production by In the cells supplemented with 100 µM AA, there was no the uterus. A mixed population of endometrial cells further increase in PGF2 output in the presence of OT or (epthelium and stroma) from late-gestation ewes were LPS and when 100 µM GLA was present neither LPS nor cultured in defined medium containing linoleic acid OT stimulated PGE2 significantly. When LPS was given (LA, 18:2, n-6), -linolenic acid (GLA, 18:3, n-6) or to AA-supplemented cells, the E:F ratio was increased. arachidonic acid (AA, 20:4, n-6) in concentrations of 0 DEX did not change PGE2 production in control or (control), 20 or 100 µM. After 45 h in test medium with or LA-treated cells, but the cells produced significantly less without added PUFAs, cells were challenged with control PGF2, so the E:F ratio was increased. In contrast, in medium (CM), oxytocin (OT, 250 nM), lipopolysaccha- GLA- and AA-treated cells, DEX reduced the production ride (LPS, 0·1 µg/ml) or dexamethasone (DEX, 5 µM) for of both PGF2 and PGE2, so the E:F ratio was unaltered.
    [Show full text]
  • Antioxidant Properties
    David Fernandes Farinha Licenciado em Química Aplicada Selenium-containing polyphenols: antioxidant properties Dissertação para obtenção do Grau de Mestre em Química Bioorgânica Orientador: Dra. Alexandra M. M. Antunes, CQE-IST-UL Co-orientador: Dr. João Paulo Telo, CQE-IST-UL Júri: Presidente: Prof. Doutora Paula Cristina de Sério Branco Arguente(s): Prof. Doutora Luísa Pinto Ferreira Outubro 2016 Selenium-containing polyphenols: antioxidant properties. Copyright David Fernandes Farinha A Faculdade de Ciências e Tecnologia e a Universidade Nova de Lisboa têm o direito, perpétuo e sem limites geográficos, de arquivar e publicar esta dissertação através de exemplares impressos reproduzidos em papel ou de forma digital, ou por qualquer outro meio conhecido ou que venha a ser inventado, e de a divulgar através de repositórios científicos e de admitir a sua cópia e distribuição com objectivos educacionais ou de investigação, não comerciais, desde que seja dado crédito ao autor e editor. 2 Resumo Apesar de não ser recente, o interesse em compostos orgânicos contendo selénio na sua composição tem vindo a ser cada vez maior, em grande parte devido ao seu potencial antioxidante e anticarcinogénico. Nesse sentido, a introdução de um átomo de selénio em moléculas onde este não existe inicialmente é vista como uma técnica promissora na busca de antioxidantes mais potentes e versáteis para possíveis fins biomédicos. Este trabalho teve como objectivo a introdução de um átomo de selénio em diferentes estruturas moleculares, de forma a obter um painel de compostos que pudessem ser testados pela sua potencial actividade antioxidante. Para tal, foi inicialmente testado um método de síntese de purinas selenadas com recurso a microondas.
    [Show full text]
  • Selenium Enhances the Efficacy of Radachlorin Mediated- Photodynamic Therapy in TC-1 Tumor Development
    576 ONCOLOGY REPORTS 28: 576-584, 2012 Selenium enhances the efficacy of Radachlorin mediated- photodynamic therapy in TC-1 tumor development YONG-WAN KIM1, SU MI BAE1, HAI-BO LIU1, IN-WOOK KIM1, HEUNG-JAE CHUN2 and WOONG SHICK AHN3 1Catholic Research Institutes of Medical Science, 2Institute of Cell and Tissue Engineering and 3Department of Obstetrics and Gynecology, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea Received January 17, 2012; Accepted March 9, 2012 DOI: 10.3892/or.2012.1820 Abstract. Selenium, an essential trace element possessing anti- tive photodynamic destruction of tumor cells. The evident carcinogenic properties, can induce apoptosis in cancer cells. advantage of PDT over other conventional cancer treatments Our goal was to investigate the enhanced antitumor effects of such as chemotherapy and radiotherapy is its minimal invasive- photodynamic therapy (PDT) plus selenium in TC-1 tumor cells ness, selective targeting, and reduced toxicity, which allows and implanted mice. Cell viability was evaluated at various time for repeated treatment (1). Currently, PDT is being success- intervals after PDT treatment and/or selenium by methyl thia- fully used for the treatment of early lung cancers (2,3) and in zolyl tetrazolium (MTT) assay. When only PDT treatment was dermatology for the treatment of non-melanoma skin cancers administered to TC-1 tumor cells, TC-1 cell growth recovered and precancerous diseases (4). PDT has also been successfully over time. On the other hand, co-treatment of PDT and selenium employed to treat early carcinomas of the oral cavity and larynx extended the inhibition time of tumor cell growth.
    [Show full text]
  • Molecular Targets for Nutrients Involved with Cancer Prevention
    NUTRITION AND CANCER, 41(1&2), 1–16 REVIEWS Molecular Targets for Nutrients Involved With Cancer Prevention John A. Milner, Sharon S. McDonald, Darrell E. Anderson, and Peter Greenwald Abstract: Dietary nutrients can influence cancer risk by in- foods and their bioactive components represents a nonin- hibiting or enhancing carcinogenesis through diverse mech- vasive and cost-effective strategy for reducing risk. The anisms of action. The identification and elucidation of their melding of information from epidemiological, preclinical, sites of action have been a focus of nutrition and cancer re- and clinical studies has provided fundamental insights about search for more than four decades. Transforming nutrition the dynamic relationships among nutrients, defined here as and cancer research from a predominantly observational to any substance in the diet that brings about a physiological ef- a molecular approach offers exciting opportunities for truly fect, and cancer. Unfortunately, far too often, data across identifying those who will and will not benefit from dietary studies are inconclusive or even diametrically opposed. De- intervention strategies. The emerging field of nutritional veloping a better understanding of nutrient interactions at genomics, defined here as the study of any genetic or epige- the molecular level offers one avenue for traversing this co- netic interaction with a nutrient, will be key to this evolution. nundrum, although significant challenges, both scientific Unraveling which genetic upregulation or downregulation and technological, must be overcome before realistic appli- leads to subsequent phenotype changes will not be easy. cations for cancer prevention can be realized (1). DellaPenna There is evidence that genetic polymorphisms can influence (2) coined the term nutritional genomics to describe work at the dynamics between nutrients and molecular targets and, the interface of plant biochemistry, genomics, and human thus, contribute to variation in response among individuals.
    [Show full text]