Saturday, 28 November 2020

Metallothionein: a Potential Link in the Regulation of Zinc in Nutritional Immunity

Biological Trace Element Research March 2018, Volume 182, Issue 1, pp 1-13
Mohammad Tariqur Rahman, et al.

(AA) Nutritional immunity describes mechanisms for withholding essential transition metals as well as directing the toxicity of these metals against infectious agents. Zinc is one of these transition elements that are essential for both humans and microbial pathogens. At the same time, Zn can be toxic both for man and microbes if its concentration is higher than the tolerance limit. Therefore a "delicate" balance of Zn must be maintained to keep the immune cells surveilling while making the level of Zn either to starve or to intoxicate the pathogens. On the other hand, the invading pathogens will exploit the host Zn pool for its survival and replication. Apparently, different sets of protein in human and bacteria are involved to maintain their Zn need. Metallothionein (MT)-a group of low molecular weight proteins, is well known for its Zn-binding ability and is expected to play an important role in that Zn balance at the time of active infection. However, the differences in structural, functional, and molecular control of biosynthesis between human and bacterial MT might play an important role to determine the proper use of Zn and the winning side. The current review explains the possible involvement of human and bacterial MT at the time of infection to control and exploit Zn for their need. 
Magnesium-Zinc-Calcium-Vitamin D Co-supplementation Improves Hormonal Profiles, Biomarkers of Inflammation and Oxidative Stress in Women with Polycystic Ovary Syndrome: a Randomized, Double-Blind, Placebo-Controlled Trial

Biological Trace Element Research March 2018, Volume 182, Issue 1, pp 21-28
Maryam Maktabi, et al.

(AA) Data on the effects of magnesium-zinc-calcium-vitamin D co-supplementation on hormonal profiles, biomarkers of inflammation, and oxidative stress among women with polycystic ovary syndrome (PCOS) are scarce. The objective of this study was to assess the effects of magnesium-zinc-calcium-vitamin D co-supplementation on hormonal profiles, biomarkers of inflammation, and oxidative stress in women with PCOS. Sixty PCOS women were randomized into two groups and treated with 100 mg magnesium, 4 mg zinc, 400 mg calcium plus 200 IU vitamin D supplements (n = 30), or placebo (n = 30) twice a day for 12 weeks. Hormonal profiles, biomarkers of inflammation, and oxidative stress were assessed at baseline and at end-of-treatment. After the 12-week intervention, compared with the placebo, magnesium-zinc-calcium-vitamin D co-supplementation resulted in significant reductions in hirsutism (−2.4 ± 1.2 vs. −0.1 ± 0.4, P < 0.001), serum high sensitivity C-reactive protein (−0.7 ± 0.8 vs. +0.2 ± 1.8 mg/L, P < 0.001), and plasma malondialdehyde (−0.4 ± 0.3 vs. +0.2 ± 1.0 μmol/L, P = 0.01), and a significant increase in plasma total antioxidant capacity concentrations (+46.6 ± 66.5 vs. −7.7 ± 130.1 mmol/L, P = 0.04). We failed to find any significant effect of magnesium-zinc-calcium-vitamin D co-supplementation on free androgen index, and other biomarkers of inflammation and oxidative stress. Overall, magnesium-zinc-calcium-vitamin D co-supplementation for 12 weeks among PCOS women had beneficial effects on hormonal profiles, biomarkers of inflammation, and oxidative stress.
Prevalence of inadequate micronutrient intakes of Canadian long-term care residents
Heather H. Keller, et al.

(AA) This study determines the prevalence of inadequate micronutrient intakes consumed by long-term care (LTC) residents. This cross-sectional study was completed in thirty-two LTC homes in four Canadian provinces. Weighed and estimated food and beverage intake were collected over 3 non-consecutive days from 632 randomly selected residents. Nutrient intakes were adjusted for intra-individual variation and compared with the Dietary Reference Intakes. Proportion of participants, stratified by sex and use of modified (MTF) or regular texture foods, with intakes below the Estimated Average Requirement (EAR) or Adequate Intake (AI), were identified. Numbers of participants that met these adequacy values with use of micronutrient supplements was determined. Mean age of males (n 197) was 85·2 (sd 7·6) years and females (n 435) was 87·4 (sd 7·8) years. In all, 33 % consumed MTF; 78·2 % (males) and 76·1 % (females) took at least one micronutrient pill. Participants on a MTF had lower intake for some nutrients (males=4; females=8), but also consumed a few nutrients in larger amounts than regular texture consumers (males=4; females =1). More than 50 % of participants in both sexes and texture groups consumed inadequate amounts of folate, vitamins B6, Ca, Mg and Zn (males only), with >90 % consuming amounts below the EAR/AI for vitamin D, E, K, Mg (males only) and K. Vitamin D supplements resolved inadequate intakes for 50-70 % of participants. High proportions of LTC residents have intakes for nine of twenty nutrients examined below the EAR or AI. Strategies to improve intake specific to these nutrients are needed.