Role of metal ions


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  • Part of the male reproductive tract
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  • Role of metal ions

    1. 1. THE ROLE OF METAL IONS IN MALEREPRODUCTIONByFalana Benedict AbiolaB.Sc.(Hons), Ilorin 2002; M.Sc. Ile-Ife 2009Matric Number: 109091016Department of Anatomy, College ofMedicine of the University of Lagos.Nigeria.Practice Seminar II
    2. 2. OUTLINEIntroductionTransport/storage problemsMechanism of membrane transportClassificationBioavailability of ionsLiterature reviewConclusionReferences
    3. 3. INTRODUCTIONA metal atom that has either lostor gained an electronA metal ion is thus a metal atomwith a charge.
    4. 4. INTRODUCTIONExert a wide variety of adverseeffects on reproduction anddevelopment( Apostoli and Catalini 2011).
    5. 5. INTRODUCTION Metalloenzymeshydrolytic enzymescatalyze addition or removal of water in asubstratee.g. carbonic anhydrase catalyzes CO2 + H2O →H2CO3redox enzymescatalyze oxidation/reduction of substratee.g. oxidation of hydrocarbons to alcohol by cyt-P450 (Fe-porphyin)e.g. nitrogenase: reduces N2 to NH3 (6 electron
    6. 6. INTRODUCTIONSpecific Metal Ions.Calcium - ZincChromium -PhosphorusPotassium -ManganeseSelenium - Other heavy metals like Cd, Pb
    7. 7. Part of the male reproductive tract .Pastor-Soler N et al. Physiology 2005;20:417-428©2005 by American Physiological Society
    8. 8. ION TRANSPORTCapture of Trace Ions from the EnvironmentControl of Concentration is essential for lifeBulk ions present in high concentrationTrace ions must be actively accumulatedSelectivity of Ion Uptake is EssentialToxic ions must be excludedBeneficial ions must be accumulated
    9. 9. ION TRANSPORTCharged Ions must pass through aHydrophobic MembraneNeutral gases (O2, CO2) and low chargedensity ions (anions) can move directlythrough the membraneHigh charge density cations require helpOnce
    10. 10. MECHANISMS FOR MEMBRANETRANSPORTIonophores: special carrier molecules thatwrap around metal ions so they can passthrough the membrane by diffusion.Ion Channels: large, membrane-spanningmolecule that form a hydrophilic path fordiffusionIon Pumps: molecules using energy totransport ions in one direction through amembrane
    11. 11. MECHANISMS FOR MEMBRANETRANSPORTPassive Transport: moves ions down theconcentration gradient, requiring no energysourceActive Transport: moves ions against theconcentration gradient, requiring energy fromATP hydrolysis
    12. 12. CLASSIFICATION OF MINERALSMacro or MajormineralsSodium,potassium,magnesium,calcium,phosphorus,sulfur,chloride. Micro or Traceminerals (bodyneeds relativelyless)Chromium,manganese, iron,cobalt,molybdenum,copper, zinc,fluoride, iodine,selenium,silicon, tin,arsenic, nickel.
    13. 13. CALCIUM Developing and maintaininghealthy bones and teeth, Blood clotting, musclecontraction and nervetransmission, oxygen transport,cellular secretion of fluids andenzyme activity, optimal intakehelps reduce the risk ofosteoporosis.
    14. 14. CHROMIUMAids in glucose metabolismPotentiates insulin and serves as acomponent of glucose tolerancefactor.
    15. 15. POTASSIUMRegulates heartbeatmaintains fluid balance helps muscle contract.
    16. 16. SELENIUM Component of glutathione peroxidasecatalyzes removal of hydrogen peroxide Component of iodothyronine-5’- deiodinaseConverts T4 to T3 Improves killing ability of neutrophilsGSH = reduced glutathioneGSSG = oxidized glutathioneGSH + H2O2 GSSG + H2O
    17. 17. PHOSPHORUSWorks with calcium to develop andmaintain strong bones and teeth Enhances use of other nutrients Plays a key role in cell membraneintegrity and intercellularcommunication critical for properenergy processing in the body.
    18. 18. MANGANESEKey component of enzymesystem including oxygen handlingenzymes, supports brain functionand reproduction.Required for blood sugarformation and part of bonestructure.
    19. 19. MINERALSEssential minerals Essential trace andmineralsNon essentialcontaminantmineralsCalcium Chromium AluminumChloride Copper Arsenic (in abundance)Magnesium Cobalt BariumPhosphorus Fluorine BerylliumPotassium Iodine CadmiumSodium Iron LeadSulphur Manganese LithiumMolybdenum MercurySelenium RubidiumVanadium StrontiumZinc REFERENCE: NFM 38,NFM Nutrition ScienceNews; December 2005
    20. 20. MINERALSMineral Contaminate body partaffectedProtective nutrientAluminum Stomach bone brain Possibly magnesiumArsenic Cells (cellular metabolism) Selenium, iodine, calciumzinc, vitamin C, sulphuramino acids)Cadmium Renal cortex of the kidney,Heart, blood vessels to thebrain appetite and smellcentre, every known processin the development ofCancerZinc, Calcium, Vitamin CSulphur ammo acidsLead Bone, Liver, Kidney,Testes,Pancreas Heart,Brain, Nervous systemZinc, Iron Calcium, VitamC, Vitamin E, Sulphur,Amino acidsMercury Nervous system, appetiteand pain centre of the brain,Immune system CellmembranesREFERENCE: NFM 38,NFM Nutrition ScienceNews; December 2005
    21. 21. NON ESSENTIAL MINERALSHumans are exposed toenvironmentally andoccupationally to metal aerosolsincluding lead and cadmium (Benoffet al., 2000;Akinloye et al 2006 ).These toxicant accumulate inmale reproductive organs (Benoff etal., 2000).
    22. 22. CA+ AND K+ CHANELLSMultiple Ca2+ and K+ Channelshave been identified in human testesand spermatozoa These channels are involved in earlyevents of acrosome reactions, thesechannels offer entry paths for metallictoxicants into mature spermatozoa.(Benoff et al., 2000)
    23. 23. REPRODUCTIVETOXICANTS2,5 hexanedione ( Sertoli celltoxicant),Ethylene glycol monomethyl etherEGME; (Spermatocytes toxicant),Cyclophosphamide(Spermatogoonia toxicant), andSulphalazin. Fukushima et al., (2005)
    24. 24. BIOAVAILABILITYBioavailabilityInfluenced by genetics, aging,nutritional status & other foodcompoundsAbsorptionSmall intestine & large intestineRegulationKidneys & small intestine
    26. 26. WHY ARE CERTAIN METAL IONSINVOLVED?A. Rule of Abundancewhen a process can be accomplished usingany of several metal ions, then the moleculewill “pick” the most abundant ione.g. Ca+2and Sr+2carbonate/phosphatecompounds equally insoluble. Why aren’tbones made from Sr? (Ca is much moreabundant)e.g. Zn enzymes can use Co+2effectively, but“chose” Zn because it is much more abundant
    27. 27. WHY ARE CERTAIN METAL IONSINVOLVED?B. Rule of Efficiencyan organism will utilize the most efficient ion iftwo are in equal abundancee.g. two electron carriers:flavodoxins (-0.185V potential) with no metalionferridoxins (-0.420V) Fe-S metalloenzymeboth are similar in function, but the ferridoxins aremuch more efficient and powerful than theflavodoxins and are therefore employed more
    28. 28. WHY ARE CERTAIN METAL IONSINVOLVED?C. Rule of Basic Fitness (MostImportant!)no matter how abundant an ionis, if it can’t do the job it isn’tgoing to be used.the ion has to function in anaqueous solution at neutral pHand ~25oC, so most “jobs” canonly be performed by a limitednumber of ions.
    29. 29. LITERATURE REVIEWMetal ions act as matchmakersfor proteins. Yi Lu ( 2009).Match makers for single domainproteins. Salgado et al (2010).
    30. 30. METAL IONS ANDREPRODUCTIONMercury intoxication has beenassociated with male reproductivetoxicity in the experimentalanimals.( Rao and Sharma 2001).
    31. 31. METAL IONS AND REPRODUCTIONSelenium and zinc administrationwas reported to attenuate leadreproductive toxicity in male SD-rats ( Falana and Oyeyipo 2012)
    32. 32. METAL IONS ANDREPRODUCTIONMercury may induce oxidativedamages in rat tissues asevidenced by increase in MDAlevels and depleted GSHcontent. (Sener et al., 2003)
    33. 33. METAL IONS ANDREPRODUCTIONMercury produces asignificant reduction inepididymal sperm viabilityand motility in murines (Rao and Sharma 2001)
    34. 34. METAL IONS AND REPRODUCTIONZinc is an essential trace elementfor spermatogenesis (Yamaguchi etal., 2009)Co administration of zinc withfolic acid has been shown to boostpenile enlargement. (Yamaguchi etal., 2009)
    35. 35. METAL IONS ANDREPRODUCTION Zinc plays an important role in DNA replication,transcription and protein synthesis influencing celldivision and differentiation (Anderson and Desmic 1999) Zinc is a critical element in male reproductive systemfor proper hormonal metabolism, sperm formation andmotility, zinc deficiency has been associated withimpotence and reduced sexual performance (ModupeOgunlesi 2009)
    36. 36. METAL IONS AND REPRODUCTIONOccupational and environmentalexposures to toxic pollutantscontributes significantly todeclining sperm concentrationsand male infertility (Carlsen et al.,1992, Agar et al., 1995,, Adamopoulous et al.,1996, Bcker and berhane 1997)
    37. 37. METAL IONS AND REPRODUCTIONThese study was criticizedbecause it fails to consider thatsperm counts clearly differ bygeographic location (Fisch andGolubuff 1996; Paulsen et al 1996; Carlsen et al., 1992)
    38. 38. METAL IONS AND REPRODUCTIONNonethe less geographicvariations in semen quality (Fisch andGoluboff 1996; becker and Behane 1997) may stillbe inluencd by environmentalfactors ( Fisch and Goluboff 1996) whichexhibit considerable variationbetween climatic seasons (Sram et al1996)
    39. 39. METAL IONS AND REPRODUCTIONMore importantly, environmentalfactors differ between areas ( Fribergand Vahter 1983., Svenson et al 1987; Buchancova et al.,1994; Sram et al.,1996) with higher amountof pollutants closer to sources ofindustrialisation (Benin et al., 1999)
    40. 40. METAL IONS AND REPRODUCTIONPb2+ and Cd2+ prefentiallyaccumulate in male reproductiveorgans ( Danielson et al., 1984; Oldereid et al.,1993; jackson et al 1995)An increase in Pb2+ and Cd2+often occur simultaneously ( Stachelet al., 1989)
    41. 41. METAL IONS AND REPRODUCTIONSeveral death pathways will be activatedfollowing lead toxicity .(Kumari et al.,2013)Mitochondrial pathway which involvesthe inhibition of the heme a3-cuBetabinuclear centre of Ccox: an enzymeconcerned with the conversion ofmolecular oxygen into water at complexV of the ETC.
    42. 42. METAL IONS AND REPRODUCTIONPrevious studies have shown thatheavy metals like Mercury,cadmium and lead are capable ofinducing wide range toxicity inthe germinal epithelium (Xiao et al.,2010)
    43. 43. METAL IONS IN REPRODUCTIONMorphometric studies reveals lowcell count, distorted lumen andcell death in general;Other physiological changesinclude male infertility andtumorigenesis (Xiao et al., 2012)
    44. 44. SUMMARY AND CONCLUSIONTerminating the cause(s)Nanoparticles awarenessGovernment policiesOccupational and environmentalproblems revisited.
    45. 45. THANKSThanks for listening.
    46. 46. REFERENCES Apostoli P and Catalini, S (2011). Metal ions Affecting Reproduction andDevelopment. Met ions life sci.8: 263-303 Adamopoulos DA., Pappa A, Nicopoulou, S. et al., (1996). Seminal volumeand total sperm number trends in men attending sub-fertility clinics in thegreater Athens area during the period 1977-1993. Reprod.,9, 1936-1941 Atar D, Backx,PH, Appel MM. et al .,(1995). Excitation-Transcriptioncoupling mediated by zinc influx through voltage-dependent calciumchanels.J.Biol.Chem, 270,2473-2477 Becker, S. and Berhane, K (1997) A met-analysis of 61 sperm count studiesrevisited. Fertil.steril., 67,1103-1108 Bennof, S, Jabbob, A and Hurley, R (2000).Male fertility and environmentalexposure to lead and cadmium. Human reproduction update (6) 2:107-121 Jenny.P. glusker, Amy K. Kats and Charles W. Bock (1999).Metal ions inbiological system .The Rigaku Journal 16(2):1-10
    47. 47. REFERENCES Benin AL, Sargent JD., DaltonM, et al., (1999).High Concentrations ofHeavy metals in Neighborhoods near Ore smelters in NorthernMexico.Environ.Health Perspect.,107,279-284 Buchancova, J.,Knizkova, M.,Hyllova, al (1994) Content of selectedtrace elements (Al, As,Cd,Cu,Fe,Hg,Mn,Ni,Pb,Zn) in blood urine, hair ofblood donors without occupational exposure to theses metals.CentEur.J.Public health,2,82-87 Carlsen, E.,Giwercman, A.,Keiding,Net al (1992). Evidence for decreasingquality of semen during the past 50 years.Br.Med.J.305, 609-613 Falana, B.A and Oyeyipo, I.P (2012). Selenium and Zinc Attenuate Lead-induced reroductive toxicity in male Sprague-Dawley Rats. ResearchJournal of Medical Sciences 6(2):66-70 Fisch, H and Goluboff E.T (1996).Geographic Variations in Sperm Counts:A Potential Cause o Bias in Studies of Semen Quality. Fertil.Steril.65,1044-1046
    48. 48. REFERENCES Fukushima et al., (2005). Effects of Male ReproductiveToxicant on Gene Expression in Rat Testes.J.Toxicol.Sci.30(3):195-206 Hidiroglou M, and Knipfel J.E (1984). Zinc in MammalianSperm: A Review.J.Diary. Sc.i 67:1147-1156 Glusker, JP, Kats AK, and Bock C.W (1999).Metal ions inBiological Systems. The Rigaku Journal 16(2):1-10 Matzui MM, and Lamb DJ. Genetic Dissection of MammalianFertility 8 suppl:533-540 Markku Saaranen (1990). Glutathione Peroxidase and SomeMetal ions in Male Reproductive System 69,(5): 453-454 Merker HJ and Gunther T.(1997). Testis Damage Induced byZinc deficiency in Rat. J.Trace element 11:19-22
    49. 49. REFERENCES Miura T, Ando A, Miura C, Yamauchi K .(2002). Comparative StudiesBetween Invivo and Invitro Spermatogenesis of Japanesse Eel(Anguinajaponica). Proc Natl Acad Sci USA 88:5774-5778 Miura T, Higuchi M, Ozaki Y, Ohta ,T and Miura C.(2006) .Progestin is anessential factor for the initiation of meiosis in spermatogenic cell of theeel.Proc. Natl .Acad.Sci .USA 103:7333-7338 Miura T, Yamauchi K, Takahashi H, and Nagahama, Y (1991) HormonalInduction of all the Stages of Spermatogenesis invitro in the Male JapaneseEel (Anguilla japonica) Proc. Natl .Acad .Sci. USA ,88:5774-5778 Morisawa M, and Mohri H. (1972).Heavy Metals and SpermatozoonMotility. I. distribution of iron, zinc, and copper in sea urchin spermatozoa.Exp.Cell.Res.70:311-316 Salgado, E.N et al.,(2010) Metal Templated design of protein interfaces.Proc.Natl. Acad .Sci .USA ,107:1827-1832
    50. 50. REFERENCES Ogunlesi Modupe(2009) Determination of theconcentration of zinc and vitamin c in oyster and somemedicinal plants used to correct male factor fertility.Journal of Natural Product 2:89-97. Yamamoto et al.,(2005). Protein expression analysis ofrat testes induced testicular toxicity with severalreproductive toxicants. The Journal of ToxicologicalSciences 30(2):111-126 Yi Lu (2009). Metal ions as matchmakers for protein.Current Issue 107(5):234-239. Xiao X, Mruk DD, Cheng FL, Cheng CY (2012). C-Srcand C-Yes are two unlikely partners ofspermatogenesis and their roles in blood-testes barrierdynamics. Adv Exp Med Biol. 763: 295-317.