Metallothionein expression is increased in monocytes and erythrocytes of young men during zinc supplementation

• Published in: The Journal of nutrition Vol. 128; no. 4; pp. 707 - 713
• Main Authors: Sullivan, V.K. (University of North Florida, Jacksonville, FL.), Burnett, F.R, Cousins, R.J
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Nutritional Sciences 01.04.1998; American Institute of Nutrition
• Subjects: Adult; ADULTE; ADULTOS; ADULTS; ARN MENSAJERO; ARN MESSAGER; Biological and medical sciences; blood; BLOOD PLASMA; CINC; COBRE; COMPLEMENT ALIMENTAIRE; COPPER; Copper - blood; CUIVRE; dietary mineral supplements; Dietary Supplements; duration; Enzyme-Linked Immunosorbent Assay; ERITROCITOS; ERYTHROCYTE; ERYTHROCYTES; Erythrocytes - metabolism; EXPRESION GENICA; EXPRESSION DES GENES; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; GENE EXPRESSION; genetics; HOMBRES; HOMME; Humans; Male; MEN; MESSENGER RNA; metabolism; METALLOPROTEINE; METALLOPROTEINS; metallothionein; Metallothionein - genetics; Metallothionein - metabolism; METALPROTEINAS; MINERAL NUTRIENTS; MONOCITOS; MONOCYTE; MONOCYTES; Monocytes - metabolism; NUTRIENTES MINERALES; pharmacology; PLASMA SANGUIN; PLASMA SANGUINEO; Polymerase Chain Reaction; Proteins; RNA, Messenger; RNA, Messenger - metabolism; SUBSTANCE NUTRITIVE MINERALE; SUPLEMENTOS; SUPPLEMENTS; TEMPS; THIONEINE; THIONEINS; TIEMPO; TIME; Time Factors; TIONEINA; Transcription, Genetic; Vertebrates: anatomy and physiology, studies on body, several organs or systems; YOUNG ADULTS; ZINC; Zinc - blood; Zinc - pharmacology; Micronutrient; Human; Blood cell; Monocyte; Red blood cell; Biological marker; Trace element (nutrient); Supplementation; Gene expression; Nutritional status; Metallothionein; Zinc
• ISSN: 0022-3166; 1541-6100
• DOI: 10.1093/jn/128.4.707

The metallothionein gene is transcriptionally regulated by zinc. Consequently, metallothionein has potential for serving as an index of dietary zinc status in humans. To examine this possibility, an enzyme-linked immunoassay (ELISA) based on a sandwich approach that utilizes monoclonal and chicken egg yolk antibodies was used to compare the response of erythrocyte metallothionein protein levels with the response of monocyte metallothionein mRNA levels as measured by competitive reverse transcriptase-polymerase chain reaction (CRT-PCR) during zinc supplementation. Young male subjects participated in an 18-d supplementation study in which zinc was provided at 50 mg/d. Control subjects received a placebo. The zinc supplement resulted in significantly greater erythrocyte metallothionein levels by d 8 of supplementation compared with controls. Monocyte metallothionein mRNA levels were significantly greater than those of controls by d 2 of supplementation. Both remained elevated through d 18. They returned to base line by 8 and 4 d after supplementation, respectively. The plasma zinc concentration was significantly greater than in controls by d 6 and had returned to control levels by d 22 of supplementation. The results presented here show that both monocyte metallothionein mRNA and erythrocyte metallothionein protein concentrations change in human subjects in response to elevated dietary zinc intake and that monocyte metallothionein mRNA responds more rapidly to elevation of dietary zinc status than erythrocyte metallothionein protein. Consequently, both erythrocyte metallothionein and monocyte metallothionein mRNA may prove to be measures useful for assessment of either zinc depletion or the bioavailability of zinc supplements