Poster Topical Area: Vitamins and Minerals

Location: Hall D

Poster Board Number: 485

P26-024 - Effects of extracellular zinc on mRNA expression of zinc transporters and metallothioneins in peripheral blood mononuclear cells

Sunday, Jun 10
8:00 AM – 6:00 PM

Background: Zinc is an essential nutrient for humans; however, a sensitive biomarker to assess zinc status has not been identified. Objective: To determine the sensitivity of zinc transporter and metallothionein (MT) mRNA in peripheral blood mononuclear cells (PBMCs) to extracellular zinc. Design: Human PBMCs were cultured in medium alone (control) or medium with 10 or 50 μM ZnSO4 or 50 μM ZnSO4 and 5 μM TPEN (n=5/treatment) for 24 h. Cells were collected and mRNA expression of SLC30A1-10, SLC39A1-14, MT1 subtypes (A, B, E, F, G, H, L, M, and X), MT2A, MT3, and MT4 was determined by real-time qRT-PCR.
Results: The most highly expressed genes were: control, SLC30A1 > SLC30A7 > SLC30A5 > SLC39A1 > and SLC39A8; 10 μM, SLC30A1 > MT1X > SLC30A7 > SLC39A1 > and SLC39A8; 50 μM, MT1L > MT1X > MT1M > SLC30A1 > and MT1A; TPEN, SLC30A1 > SLC30A7 > MT1X > SLC39A8 > and SLC30A5. MT4, SLC30A8, and SLC30A10 were below detection levels in all treatment groups and SLC30A2, SLC30A3, and SLC39A12 were expressed at low levels in response to extracellular zinc. MT1A (fold change +/- SD compared to control: 10 μM, 2.7 +/- 0.4; 50 μM, 518.7 +/- 189.6; TPEN, 2.0 +/- 1.1), MT1E (10 μM, 8.2 +/- 1.5; 50 μM, 133.2 +/- 13.4; TPEN, 5.2 +/- 1.3), MT1F (10 μM, 17.3 +/- 7.5; 50 μM, 172.9 +/- 43.2; TPEN, 9.9 +/- 4.6), MT1G (10 μM, 14.7 +/- 5.8; 50 μM, 352.0 +/- 55.5; TPEN, 7.3 +/- 3.8), MT1H (10 μM, 25.4 +/- 11.8; 50 μM, 792.0 +/- 164.1; TPEN, 11.7 +/- 4.5), MT1L (10 μM, 54.4 +/- 22.6; 50 μM, 3780.9 +/- 1088.2; TPEN, 34.7 +/- 30.2), MT1M (10 μM, 112.9 +/- 50.1; 50 μM, 3466.8 +/- 731.0; TPEN, 36.7 +/- 10.6), MT1X (10 μM, 15.2 +/- 4.6; 50 μM, 199.2 +/- 32.2; TPEN, 8.3 +/- 2.5), MT2A (10 μM, 7.4 +/- 2.2; 50 μM, 64.4 +/- 5.8; TPEN, 3.4 +/- 0.7), SLC30A1 (10 μM, 2.6 +/- 0.6; 50 μM, 6.6 +/- 0.7; TPEN, 1.8 +/- 0.5), and SLC39A8 (10 μM, 2.4 +/- 0.4; 50 μM, 5.1 +/- 1.7; TPEN, 1.9 +/- 0.4) increased (P<0.05) with increasing levels of zinc and declined (P<0.05) with the addition of TPEN. All other genes were not affected by zinc.
Conclusions: Findings elucidate the mRNA expression of all zinc transporters and MTs in PBMCs and their responsiveness to extracellular zinc. Controlled-feeding studies in humans are required to determine whether the identified zinc transporters and MTs respond to short- and long-term changes in dietary zinc intake.




Funding Source:

Views expressed herein are those of the authors and do not reflect the official policy of the Army, Department of Defense, or the US Government. U.S. Army Medical Research and Material Command and appointment to the U.S. Army Research Institute of Environmental Medicine administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and the U.S. Army Medical Research and Material Command.

CoAuthors: Alyssa Kelley, BS – U.S. Army Research Institute of Environmental Medicine; Bradley Anderson, MS, RD – U.S. Army Research Institute of Environmental Medicine; James McClung, PhD – U.S. Army Research Institute of Environmental Medicine

Stephen R. Hennigar

U.S. Army Research Institute of Environmental Medicine
Natick, Massachusetts