What are Trace Elements? - 日本医師会

1 JMAJ, August 2004 Vol. 47, No. 8351 This article is a revised English version of a paper originally published inthe Journal of the Japan Medical Association (Vol. 129, No. 5, 2003, pages 607 612).What are Trace Elements? The human body is composed of elementswhich can be roughly divided into abundantelements and Trace elements. Abundant ele-ments consist of the major elements that areinvolved in the formation of covalent bondsWhat are Trace Elements? Their deficiency and excess states JMAJ 47(8): 351 358, 2004 Osamu WADAP rofessor Emeritus, University of TokyoAbstract:Elements which are detected in small but not precisely known amountsin the living body were called Trace elements in the past.

2 Recent advances inanalytical technologies, such as the development of atomic absorption spectrom-etry, have made it possible to measure these elements precisely and to determinetheir functions and the characteristics of their deficiency and excess so-called vitamin boom has passed, and it now appears to be boom-time fortrace elements. Nowadays, cases with Trace element deficiencies are oftenencountered clinically, especially during high-calorie parenteral therapy or enteralnutrition, and congenital abnormalities of Trace element metabolism have beenclarified successively.

3 Thus, knowledge of the clinical aspects of Trace elements isbecoming indispensable for front-line ) Meanwhile, epidemiologicalsurveys and animal studies have suggested the possibility that some Trace elementdeficiencies are associated with a reduced anti-oxidant potential in organisms(which is believed to possibly underlie the onset of cancer and atherosclerosis),accelerated aging, developmental retardation in children, and an increased inci-dence of abnormal pregnancies, immunological abnormalities, and lifestyle-relateddiseases.

4 Thus, from the viewpoint of prophylactic medicine, study, survey, andprophylaxis of Trace elements are also attracting close words: Trace element; Trace element deficiency; Excess of Trace elements;Congenital abnormality in Trace element metabolismand are important constituents of tissues(oxygen, carbon, hydrogen, nitrogen, etc.), andsemi-major elements, which often exist in theionic state, and are involved in functions of theliving body through maintenance of osmoticpressure and membrane potentials (potassium,sodium, etc.)

5 Major elements account for 96% Trace Elements352 JMAJ, August 2004 Vol. 47, No. 8 Table 1 Functions of Trace Elements and Symptoms of Their Deficiency and Excess StatesTraceEnzymes containingelementthe elements andPhysiological functionsSymptoms of deficiency stateSymptoms of excess stateactive formsCarbonic anhydraseProtein metabolismMajor symptoms:Acute:PeptidaseLipid metabolismGradually exacerbatingRelative Fe-Cu deficiency,Alcohol dehydrogenaseCarbohydrate metabolismeruptions, first affectingnausea, vomiting,Alkaline phosphataseBone metabolismthe face and perineumabdominal pain, melena,PolymeraseAssociated symptoms.

6 Hyperamylasemia,Zinc fingerStomatitis, glossitis, alopecia,somnolence, hypotension, changes, abdominallung edema, diarrhea,symptoms (diarrhea, vomiting),jaundice, oliguriafeverChronic:Delayed wound healing, dwarfismReduced reproductiveGrowth retardation, negativefunction, dwarfism,N balance,taste disorder, hyposmia,Immunosuppression,anemiaMental symptoms (depression),Taste disorder, anorexiaCeruloplasminHemopoiesisAnemiaNa usea, vomiting,Monoamine oxidaseBone metabolismLeukopeniaheartburn, diarrhea,Cytochrome oxidaseConnective tissueNeutropeniajaundice, hemoglobinuria,Ascorbic acid oxidasemetabolismDisturbed maturation ofhematuria, oliguria,CopperDopamine -hydroxylasemyeloleukocytesanuria, hypotension, coma,Superoxide dismutaseBone changes (children)

7 Osseous age,irregular/spurring metaphysis,bone radiolucency,bone cortex thinningGlucose tolerance factorCarbohydrate metabolismAbnormal glucose toleranceNausea, vomiting,Cholesterol metabolismReduced respiratory quotientpeptic ulcer, CNS disorder,Connective tissueWeight lossLiver/kidney dysfunction,ChromiummetabolismPeripheral neuropathygrowth retardationProtein metabolismIncreased serum free fatty acidsAbnormal nitrogen balanceMetabolic consciousnessdisturbanceGlutathione peroxidaseAntioxidant actionMyalgia (lower extremities)Selenosis (alopecia, nail(GSH-Px)T4 T3 conversionCardiomyopathydetachment, CNS disorder)Selenium5 -deiodinase (type I)Reduced carcinogenicity(myocardial cell collapse,Various selenoproteinsactionfibrosis)Nail bed whiteningArginaseBone metabolismReduced serum cholesterolParkinsonian syndromePyruvate carboxylaseCarbohydrate metabolismReduced coagulationEarly chronic.

8 Superoxide dismutaseLipid metabolismHair reddeningImpotence, loss of vigor,ManganeseGlycosyltransferaseReprod uctionDermatitis (miliaria crystallina)somnolence, anorexia,ImmunityGrowth retardationedema, myalgia, headache,Increased radiolucency at theexcitation, fatigueepiphyses of long bonesAdvanced stage:Extrapyramidal disorderXanthine oxidaseAmino acid metabolismTachycardiaHyperuricemia, goutXanthine dehydrogenaseUric acid metabolismPolypneaAldehyde oxidaseSulfuric acid/sulfurousNight blindnessMolybdenumNitrous acid oxidaseacid metabolismScotomaIrritabilitySomnolenceD isorientationComaCobaltVitamin B12 HemopoiesisPernicious anemiaCobalt poisoningMethylmalonic acidemiaIodineThyroid hormoneTissue metabolismGoiter, hypothyroidismGoiter, hypothyroidism(Summary of many reports) , August 2004 Vol.

9 47, No. 8353of the total body weight, and the semi-majorelements account for 3 to 4% of the total bodyweight. Deficiency of major elements can leadto nutritional disorders, and their presence inexcess can cause obesity. Deficiencies or excessstates of semi-major elements often result inwater and electrolyte Trace elements of the human bodyinclude zinc (Zn), copper (Cu), selenium (Se),chromium (Cr), cobalt (Co), iodine (I), manga-nese (Mn), and molybdenum (Mo). Althoughthese elements account for only of thetotal body weight, they play significant roles, , as active centers of enzymes or as tracebioactive substances.

10 A major outcome of traceelement deficiencies is reduced activity of theconcerned enzymes. However, since each traceelement is related to so many enzymes, defi-ciency of a single Trace element is often notassociated with any specific clinical manifesta-tions, but rather manifests as a combination ofvarious symptoms. Because of the presence oftrace elements in very small amounts and theabsence of specific clinical features associatedwith their deficiency, it is often difficult forclinicians to identify deficiencies of some par-ticular Trace 1 lists the enzymes containing traceelements, and summarizes the physiologicalfunctions of Trace elements and the character-istics of their deficiency and excess Elements as Nutrients orMedicines2)Like vitamins, Trace elements were alsooriginally viewed as nutrients.