Zinc supplementation decreased ZIP4 mRNA abundance in peripheral blood mononuclear cells of rural women in south Ethiopia (1043.4)

Abstract

Understanding the control of zinc homeostasis as a result of chronic deficiency is hampered due to a lack of effective measures to assess Zn status. This randomized placebo‐controlled Zn supplementation trial in apparently healthy women evaluated effects of 20 mg Zn as Zn sulfate for 23 d on Zn transporter and metallothionein (MT) mRNA abundance and plasma Zn concentration. Non‐pregnant, non‐lactating women from rural southern Ethiopia with body mass index of 18.5‐24.9 were participants. PBMC collected from fasting blood at baseline and endpoint were stored in RNAlater. RNA was extracted from PBMC, reverse‐transcribed, and used for gene expression analyses. The mRNA abundance of Zn transporters (ZnT1/ZIP3/ZIP4) and MT1 was determined by qPCR. Plasma Zn was measured by inductively coupled plasma mass spectrometry. Abundance of ZIP4 decreased following Zn supplementation (p =0.04), though ZnT1, ZIP3 and MT1 abundance was unchanged. Despite these differences in expression, ZnT1 and ZIP4 abundance were correlated following Zn supplementation (r = 0. 934; p = 0.002). The mean (±SD) plasma Zn at baseline was 680±105 µg/L for the Zn group and 741±92 µg/L for the placebo group. At endpoint, plasma Zn in the Zn group increased to 735±79 µg/L (p<0.01) while the placebo group (717±103 µg/L) did not change from baseline (p = 0.31). Plasma Zn was not significantly related to abundance of mRNA for any Zn transporter or for MT. The observed change in ZIP4 mRNA abundance with Zn supplementation merits further investigation.Grant Funding Source: Supported by Oklahoma Agricultural Experiment Station