Determinants of serum zinc concentrations in a population of French middle-age subjects (SU.VI.MAX cohort)

Lipophilic Group-Modified Manganese(II)-Based Contrast Agents for Vascular and Hepatobiliary Magnetic Resonance Imaging

Effective vascular and hepatic enhancement and better safety are the key drivers for exploring gadolinium-free hepatobiliary contrast agents. Herein, a facile strategy proposes that the high lipophilicity may be favorable to enhancing sequentially vascular and hepatobiliary signal intensity based on the structure-activity relationship that both hepatic uptake and interaction with serum albumins partly depend on lipophilicity. Therefore, 11 newly synthesized derivatives of manganese o-phenylenediamine-N,N,N',N'-tetraacetic acid (MnLs) were evaluated as vascular and hepatobiliary agents. The maximum signal intensities of the heart, liver, and kidneys were strongly correlated with log P, a key indicator of lipophilicity. The most lipophilic agent, MnL6, showed favorable relaxivity when binding with serum albumin, good vascular enhancement, rapid excretion, and reliable hepatobiliary phases comparable to a classic hepatobiliary agent, gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) for in vivo liver tumor imaging. Inhibition experiments confirmed the hepatic targeting of MnL6 is mediated by organic anion-transporting polypeptides.

Enhancing Nutritional Status and Addressing Micronutrient Deficiencies: Evaluating the Impact of Workplace Nutrition Program on Female Workers in Vietnam

This randomized controlled clinical study aimed to assess the effectiveness of a nutrition intervention program for non-pregnant female workers in Vietnam. A total of 500 female workers were randomly assigned to the intervention and control groups. Participants in the intervention group were provided nutrition education, personalized specific dietary, and received oral nutrition supplements (ONS)-which contained multi-minerals and vitamins according to recommendations for adults for a duration of 12 wk, while participants in the control group received only nutrition education. The result shows the percentage of malnutrition by BMI in the control group rose from 15.6% to 21.3% after 12 wk; the figure for counterpart experienced a remain unchanged (p<0.05). Additionally, the mean of serum zinc in the intervention group significantly increased from 49.0±21.2 μg/dL to 53.6±19.5 μg/dL after 12 wk. Moreover, the intervention group demonstrated significant increases in serum iron and total serum calcium levels (p<0.05), with from 13.9±5.6 μmol/L to 15.3±5.8 μmol/L, and from 2.36±0.15 mmol/L to 2.4±0.09 mmol/L, respectively. The participants of the intervention group were more likely to have higher total serum calcium (Coef=0.04, p<0.05), serum iron (Coef=1.99, p<0.05), and serum zinc (Coef=18.9, p<0.05), which presents a reduce micronutrient deficiency. In conclusion, workplace nutrition interventions effectively mitigate micronutrient deficiencies and improve the nutritional status of female workers.

The association between plasma zinc concentrations and markers of glucose metabolism in adults in Cameroon

An abnormal Zn status has been suggested to play a role in the pathogenesis of type 2 diabetes. However, epidemiological studies of the relationship between plasma Zn concentrations and diabetes are sparse and inconclusive. We aimed to investigate the association between plasma Zn concentrations and glycaemic markers (fasting glucose, 2-h glucose and homeostatic model assessment of insulin resistance) in rural and urban Cameroon. We studied 596 healthy adults (63·3 % women) aged 25-55 years in a population-based cross-sectional study. The mean plasma Zn concentration was 13·7 ± 2·7 µmol/L overall, with higher levels in men (14·4 ± 2·9 µmol/l) than in women (13·2 ± 2·6 µmol/l), P-value < 0·0001. There was an inverse relationship between tertiles of plasma Zn and 2-h glucose concentrations (P-value for linear trend = 0·002). The difference in 2-h glucose between those in the highest tertile of plasma Zn compared to the lowest was -0·63 (95 % CI - 1·02, -0·23) mmol/l. This remained significant after adjusting for age, sex, smoking status, alcohol intake, education level, area of residence, adiposity and objectively measured physical activity -0·43(-0·82, -0·04). Similar inverse associations were observed between plasma Zn concentrations and fasting glucose and homeostatic model assessment of insulin resistance when adjusted for socio-demographic and health-related behavioural characteristics. The current findings of an inverse association between plasma Zn concentrations and several markers of glucose homeostasis, together with growing evidence from intervention studies, suggest a role for Zn in glucose metabolism. If supported by further evidence, strategies to improve Zn status in populations may provide a cheap public health prevention approach for diabetes.

Human Serum Supplementation Promotes Streptococcus mitis Growth and Induces Specific Transcriptomic Responses

Streptococcus mitis is a normal member of the human oral microbiota and a leading opportunistic pathogen causing infective endocarditis (IE). Despite the complex interactions between S. mitis and the human host, understanding of S. mitis physiology and its mechanisms of adaptation to host-associated environments is inadequate, especially compared with other IE bacterial pathogens. This study reports the growth-promoting effects of human serum on S. mitis and other pathogenic streptococci, including S. oralis, S. pneumoniae, and S. agalactiae. Using transcriptomic analyses, we identified that, with the addition of human serum, S. mitis downregulates uptake systems for metal ions and sugars, fatty acid biosynthetic genes, and genes involved in stress response and other processes related with growth and replication. S. mitis upregulates uptake systems for amino acids and short peptides in response to human serum. Zinc availability and environmental signals sensed by the induced short peptide binding proteins were not sufficient to confer the growth-promoting effects. More investigation is required to establish the mechanism for growth promotion. Overall, our study contributes to the fundamental understanding of S. mitis physiology under host-associated conditions. IMPORTANCE S. mitis is exposed to human serum components during commensalism in the human mouth and bloodstream pathogenesis. However, the physiological effects of serum components on this bacterium remain unclear. Using transcriptomic analyses, S. mitis biological processes that respond to the presence of human serum were revealed, improving the fundamental understanding of S. mitis physiology in human host conditions.

Zinc levels of patients with a moderate to severe COVID-19 infection at hospital admission and after 4th days of ward hospitalization and their clinical outcome

BACKGROUND

Previous studies associate the disturbance of the Zinc (Zn) status with the severity of the disease and the inflammatory process in the critically ill patient. This decrease in Zn concentrations is an indicator of poor prognosis. Our aim was to evaluate Zn levels at admission and after four days, and to study if lower Zn levels at those days were related to a worse clinical outcome.

MATERIAL AND METHODS

Observational cohort study at a tertiary Hospital. Recruitment period: 09/04/2020-04/24/2021. Clinical information on hypertension, diabetes mellitus (DM), chronic obstructive pulmonary disease (COPD), or bronchial asthma was collected. Obesity was defined as BMI ≥ 30 Kg/m2. Blood extraction was performed at admission and after 4 days. Zn was measured by atomic absorption using a flame method. Worse clinical outcome was defined as death during admission, intensive critical care unit admission or receiving supplemental oxygen through noninvasive or invasive ventilator care.

RESULTS

129 subjects were invited to participate but only 100 subjects completed the survey. According to ROC curve [AUC= 0.63 (95% CI 0.60-0.66)], Zn < 79 μg/dL showed the best performance to detect a worse outcome (Sn=0.85; Sp=0.36). Patients with Zn < 79 μg/dL were older (70 vs 61 y; p = 0.002) with no differences by sex. Most patients presented with fever, dysthermic symptoms and cough, without differences between groups. Pre-existing comorbid conditions did not differ significantly between groups. Less obese subjects were found in the Zn < 79 μg/dL group (21.4 vs 43.3%, p = 0.025). In the univariate analysis, Zn < 79 μg/dL at hospital admission was related to a worse outcome (p = 0.044), but after adjusting for age, C-reactive protein, and obesity there was no difference, but a tendency towards a worse prognosis [OR 2.20 (0.63-7.70), p = 0.215]. Zn levels increased in both groups after 4 days (66.6 vs 73.1 μg/dL at admission, and 72.2 vs 80.5 μg/dL at 4th day), with ns. difference (p = 0.214).

CONCLUSION

Zn < 79 μg/dL at admission for a moderate to severe COVID-19 infection could be related to a worse outcome, although after adjustment for age, C-reactive protein levels and obesity, this Zn level threshold did not show statistically significant difference in the composite end point, but a tendency towards a worse prognosis. In addition, patients with the best clinical evolution showed higher serum Zn levels at 4th day after hospital admission than the patients with a worse prognosis.

Zinc Status of Horses and Ponies: Relevance of Health, Horse Type, Sex, Age, and Test Material

Little is known about the animal- and diet-related factors that could interfere with the plasma zinc (Zn) concentrations of equines. Additionally, the adequacy of plasma to reflect changes in the Zn intake is unclear. In the first part of this study, the plasma Zn concentrations of hospitalized horses and ponies (n = 538) were measured and evaluated for the impact of the age, sex, horse type, and internal diseases of the animals. In the second part, the effects of increasing dietary Zn chloride hydroxide and Zn methionine supplementations were assessed on the plasma and mane hair Zn concentrations of healthy horses (n = 2) and ponies (n = 8). Part 1: The age, sex, and horse type did not influence the plasma Zn concentrations. No effect of internal diseases was observed, with the exception of higher plasma Zn concentrations in animals with metabolic disorders compared to the control group (p < 0.05). Part 2: Both Zn supplements dose-dependently increased the Zn concentrations in the mane hair (p = 0.003), but not in the plasma of the horses and ponies. In conclusion, the plasma Zn concentrations were widely unaffected by nutritional and non-nutritional factors in equines, while mane hair samples better reflected the dietary Zn supply.

Hypozincemia in the early stage of COVID-19 is associated with an increased risk of severe COVID-19

BACKGROUND & AIMS

Nutritional predisposition to severe coronavirus disease 2019 (COVID-19) remains unclear. Zinc deficiency could be critical since it is associated with a higher susceptibility to infections. We evaluated the prevalence of hypozincemia in the early stage of COVID-19, its association with risk factors for severe COVID-19 and its prognostic value for hospitalization for respiratory complications within 10 days.

METHODS

For 152 COVID-19 patients and 88 non-COVID-19 patients admitted to COVID-19 screening centers, national early warning score for COVID-19 (NEWS) and laboratory analyses were performed to identify the risk for severe COVID-19. Multivariable logistic regression analysis assessed whether hypozincemia was an independent predictor of hospitalization for respiratory complications within 10 days (primary judgment criterion). The secondary judgment criteria were high NEWS score (≥7), comorbidities and biomarkers associated with severe COVID-19.

RESULTS

Hypozincemia was more frequent in COVID-19 patients compared to non-COVID-19 patients (27.6% vs 11.4%; p = 0.003). Older patients (≥65 years) and medically assisted nursing home residents were at higher risk of hypozincemia (p < 0.01). Hypozincemia was associated with a worse NEWS score (p < 0.01) and lymphopenia (p < 0.001). Hypozincemia was independently associated with hospitalization for respiratory complications within 10 days (OR = 10.9, 95% CI = 2.3-51.6, p = 0.002).

CONCLUSIONS

In the early stage of COVID-19, the prevalence of hypozincemia exceeded 20%. Hypozincemia was an independent predictor of hospitalization for respiratory complications within 10 days. This may suggest the importance of early detection and treatment of zinc deficiency in the nutritional management of COVID-19, especially in older people. Therefore, intervention and adjuvant treatment trials are strongly needed.

Nonpharmacological Interventions for the Management of Testosterone and Sperm Parameters: A Scoping Review

PURPOSE

Testosterone replacement and associated pharmacologic agents are effective strategies to treat male hypogonadism; however, nutraceutical agents and lifestyle modification approaches have gained medical interest. The purpose of this scoping review is to highlight the evidence (or lack thereof) of nutraceuticals and lifestyle modification approaches in the management of testosterone levels and sperm parameters.

METHODS

A scoping review of nonpharmacologic interventions (supplements, herbal medicines, diets, sleep, and exercise) with the potential to improve male health was undertaken to elucidate changes in testosterone levels and sperm parameters in men with hypogonadism or infertility compared with healthy patients.

FINDINGS

A multitude of nutraceuticals and functional nutrients are purported to stimulate testosterone production; however, only a select few have had promising results, such as zinc, vitamin D (in case of hypovitaminosis D), l-arginine, mucuna, and ashwagandha, based on well-controlled randomized clinical trials of men with low testosterone levels and related problems. Except for l-arginine, these natural agents, as well as tribulus and ω3 fatty acids, can improve some degree of sperm parameters in infertile men. Before implementing these nutraceutical agents, adequate sleep, exercise, and weight loss in patients with obesity are imperative. The effects of nonpharmacologic interventions on testosterone levels are modest and hence do not directly translate into clinical benefits. Correspondingly, androgen receptor content, but not endogenous androgens, has been regarded as the principal factor in muscle hypertrophy.

IMPLICATIONS

A limited number of supplements and herbal medicines can be considered as adjunctive approaches in the management of testosterone levels and sperm parameters, primarily in men with low testosterone levels and infertility, whereas most nonpharmacologic supplements appear to lack evidence. Although proper physical exercise, sleep, and diet are indisputable approaches because of the general benefits to health, the use of nutraceuticals, if considered, must be personalized by physicians and/or registered dietitians.

Gustatory and Saliva Secretory Dysfunctions in COVID-19 Patients with Zinc Deficiency

Given the ever-progressing studies on coronavirus disease 2019 (COVID-19), it is critical to update our knowledge about COVID-19 symptomatology and pathophysiology. In the present narrative review, oral symptoms were overviewed using the latest data and their pathogenesis was hypothetically speculated. PubMed, LitCovid, ProQuest, and Google Scholar were searched for relevant studies from 1 April 2021 with a cutoff date of 31 January 2022. The literature search indicated that gustatory dysfunction and saliva secretory dysfunction are prevalent in COVID-19 patients and both dysfunctions persist after recovery from the disease, suggesting the pathogenic mechanism common to these cooccurring symptoms. COVID-19 patients are characterized by hypozincemia, in which zinc is possibly redistributed from blood to the liver at the expense of zinc in other tissues. If COVID-19 induces intracellular zinc deficiency, the activity of zinc-metalloenzyme carbonic anhydrase localized in taste buds and salivary glands may be influenced to adversely affect gustatory and saliva secretory functions. Zinc-binding metallothioneins and zinc transporters, which cooperatively control cellular zinc homeostasis, are expressed in oral tissues participating in taste and saliva secretion. Their expression dysregulation associated with COVID-19-induced zinc deficiency may have some effect on oral functions. Zinc supplementation is expected to improve oral symptoms in COVID-19 patients.

Maternal Serum Zinc Level and Pre-eclampsia Risk in African Women: a Systematic Review and Meta-analysis

Some studies have reported the association between maternal serum zinc (Zn) levels and pre-eclampsia. However, many studies have reported controversial results. Hence, this systematic review and meta-analysis was planned to generate summarized evidence on the association between maternal serum Zn levels and pre-eclampsia in African women. Four electronic databases such as PubMed, Hinari, Google Scholar, and African Journals Online were searched for studies published in English. Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument, and Newcastle-Ottawa Scale were used for data extraction and quality assessment of the included studies. The meta-regression analysis was performed by the Stata 14 software. The standardized mean difference (SMD) values of lipid profiles were computed to assess their association with pre-eclampsia at 95% CI. A total of 12 observational studies were included. The mean values of serum Zn level were significantly lower in pre-eclamptic women as compared with normotensive pregnant women (Zn = 59.40 ± 22.80 μg/dL and 80.24 ± 16.04 μg/dL), respectively. The pooled SMD of Zn was significantly reduced in pre-eclamptic women as compared with normotensive pregnant women with the SMD of -1.45 (95% CI -2.26, -0.65) at 95% CI. In this review, we found that the maternal Zn serum level was significantly reduced in pre-eclamptic women than normotensive pregnant women. This suggests that Zn could be involved in the etio-pathogenesis of pre-eclampsia. However, the specific functions of Zn in pre-eclampsia pathogenesis should be proved in large-scale clinical trial studies.

Zn-Mg and Zn-Cu alloys for stenting applications: From nanoscale mechanical characterization to in vitro degradation and biocompatibility

In the recent decades, zinc (Zn) and its alloys have been drawing attention as promising candidates for bioresorbable cardiovascular stents due to its degradation rate more suitable than magnesium (Mg) and iron (Fe) alloys. However, its mechanical properties need to be improved in order to meet the criteria for vascular stents. This work investigates the mechanical properties, biodegradability and biocompatibility of Zn-Mg and Zn-Cu alloys in order to determine a proper alloy composition for optimal stent performance. Nanoindentation measurements are performed to characterize the mechanical properties at the nanoscale as a function of the Zn microstructure variations induced by alloying. The biodegradation mechanisms are discussed and correlated to microstructure, mechanical performance and bacterial/cell response. Addition of Mg or Cu alloying elements refined the microstructure of Zn and enhanced yield strength (YS) and ultimate tensile strength (UTS) proportional to the volume fraction of secondary phases. Zn-1Mg showed the higher YS and UTS and better performance in terms of degradation stability in Hanks' solution. Zn-Cu alloys presented an antibacterial effect for S. aureus controlled by diffusion mechanisms and by contact. Biocompatibility was dependent on the degradation rate and the nature of the corrosion products.

Possible zinc deficiency in the Serbian population: examination of body fluids, whole blood and solid tissues

Studies indicate that the soil, water and consequently foodstuffs in Serbia are significantly poor in zinc (Zn), and thus, it is likely that there is a Zn deficiency in the Serbian population. This study examined the Zn status in multiple clinical samples, including body fluids (serum, cerebrospinal fluid), whole blood and Zn-rich solid tissues (thyroid and brain tissue). Differences between sex and age were also considered, and comparative analysis of Zn status with other world populations was performed. Serum samples from a large number of Serbian adults approximately had twofold lower Zn amounts when compared to other populations. A similar trend was obtained for whole blood. Males had significantly higher amounts of Zn in serum, whole blood and thyroid tissue samples than females. Higher amounts of Zn were observed in the group older than 50 years. Importantly, in thyroid and brain tissues, Zn was 10- and 20-fold lower, respectively, than reported in the literature. Our results indicate that the population in Serbia could be considered Zn deficient. Therefore, adequate oral Zn supplementation and/or foodstuff fortification should be considered to prevent the deleterious effects caused by Zn deficiency.

Therapeutic supplementation with zinc in the management of COVID-19-related diarrhea and ageusia/dysgeusia: mechanisms and clues for a personalized dosage regimen

Zinc supplementation is indicated for diarrhea and taste disorders, which are both features of COVID-19. Nevertheless, this strategy has not been tested for the treatment of these secondary complications in the current pandemic. Through an updated review, a practical appraisal was considered as a means of providing a medical nexus of therapeutic zinc regimens as an adjunct in the management of COVID-19–related diarrhea and ageusia/dysgeusia. While diarrhea and taste disorders are consequences of COVID-19, zinc supplementation is useful for non–COVID-19 patients with these clinical problems. The overwhelming evidence for supplementing with zinc in diarrhea and pneumonia is associated with the treatment of children, while for taste disorders the use of supplementing with zinc is more examined in adults. Whereas COVID-19 is more prevalent in adults, precautions should be exercised not to translate the zinc dosage used for children with diarrhea and taste disorders into the current pandemic. Therapeutic doses of zinc used for adults (∼50–150 mg/day of elemental zinc) could be included in the treatment strategies for COVID-19, but this proposal should be examined through randomized studies.

Trade-Offs between Antibacterial Resistance and Fitness Cost in the Production of Metallo-β-Lactamases by Enteric Bacteria Manifest as Sporadic Emergence of Carbapenem Resistance in a Clinical Setting

Meropenem is a clinically important antibacterial reserved for treatment of multiresistant infections. In meropenem-resistant bacteria of the family Enterobacterales, NDM-1 is considerably more common than IMP-1, despite both metallo-β-lactamases (MBLs) hydrolyzing meropenem with almost identical kinetics. We show that bla_NDM-1 consistently confers meropenem resistance in wild-type Enterobacterales, but bla_IMP-1 does not. The reason is higher bla_NDM-1 expression because of its stronger promoter. However, the cost of meropenem resistance is reduced fitness of bla_NDM-1-positive Enterobacterales. In parallel, from a clinical case, we identified multiple Enterobacter spp. isolates carrying a plasmid-encoded bla_NDM-1 having a modified promoter region. This modification lowered MBL production to a level associated with zero fitness cost, but, consequently, the isolates were not meropenem resistant. However, we identified a Klebsiella pneumoniae isolate from this same clinical case carrying the same bla_NDM-1 plasmid. This isolate was meropenem resistant despite low-level NDM-1 production because of a ramR mutation reducing envelope permeability. Overall, therefore, we show how the resistance/fitness trade-off for MBL carriage can be resolved. The result is sporadic emergence of meropenem resistance in a clinical setting.

Age, sex and BMI influence on copper, zinc and their major serum carrier proteins in a large European population including Nonagenarian Offspring from MARK-AGE study

The analysis of copper (Cu) and zinc (Zn) along with their major serum carriers, albumin (Alb) and ceruloplasmin (Cp), could provide information on the capacity of humans to maintain homeostasis of metals (metallostasis). However, their relationship with aging, sex, BMI, as well as with nutritional and inflammatory markers was never investigated in a large-scale study. Here, we report results from the European large-scale cross-sectional study MARK-AGE in which Cu, Zn, Alb, Cp as well as nutritional and inflammatory parameters were determined in 2424 age-stratified subjects (35-75 years) including the general population (RASIG), nonagenarian offspring (GO), a well-studied genetic model of longevity, and spouses of GO (SGO). In RASIG, Cu to Zn ratio and Cp to Alb ratio were higher in women than in men. Both ratios increased with aging because Cu and Cp increased and Alb and Zn decreased. Cu, Zn, Alb and Cp were found associated with several inflammatory as well as nutritional biomarkers.GO showed higher Zn levels and higher Zn to Alb ratio compared to RASIG, but we did not observe significant differences with SGO, likely as a consequence of the low sample size of SGO and the shared environment. Our results show that aging, sex, BMI and GO status are characterized by different levels of Cu, Zn and their serum carrier proteins. These data and their relationship with inflammatory biomarkers support the concept that loss of metallostasis is a characteristic of inflammaging.

Zinc supplementation combined with antidepressant drugs for treatment of patients with depression: a systematic review and meta-analysis

CONTEXT

Zinc is an essential trace mineral required for the function of brain and neural structures. The role of zinc supplementation in the prevention and treatment of depression has been suggested in clinical studies that reported a reduction in depressive symptoms.

OBJECTIVE

The aim of this review was to determine whether zinc supplementation vs placebo can prevent or improve depressive symptoms in children, adolescents, or adults.

DATA SOURCES

Five electronic databases were searched, and studies published until September 2019 were included without language restriction.

STUDY SELECTION

Randomized, controlled, crossover trials that evaluated the effect of zinc supplementation vs a comparator for prevention or improvement of depressive symptoms in children, adolescents, or adults were eligible for inclusion.

DATA EXTRACTION

Two authors independently performed data extraction and risk-of-bias assessment.

RESULTS

The initial search identified 12 322 studies, 5 of which were eligible for meta-analysis. The standardized mean difference (SMD) showed an average reduction of 0.36 point (95%CI, -0.67 to -0.04) in the intervention group compared with the placebo group. Forstudies in which the mean age of participants was ≥ 40 years, the SMD was reduced by 0.61 point (95%CI, -1.12 to -0.09) in the intervention group vs the placebo group. The meta-analysis by sample size (< 60 individuals and  ≥ 60 individuals) did not show an effect of zinc supplementation in reducing depressive symptoms (SMD -0.28; 95%CI, -0.67 to -0.10; and SMD -0.52; 95%CI, -1.10 to 0.06).

CONCLUSION

Zinc supplementation may reduce depressive symptoms in individuals treated with antidepressant drugs for clinical depression.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42018081691.

Zinc deficiency is highly prevalent and spatially dependent over short distances in Ethiopia

Zinc (Zn) is an essential nutrient for human health. In Ethiopia, a high prevalence of Zn deficiency has been reported. To explore demographic variation and spatial dependencies in the Zn status of the Ethiopian population, we analyzed archived serum samples (n = 3373) from the 2015 Ethiopian National Micronutrient Survey (ENMS), a cross-sectional survey of young children, school-age children, women of reproductive age (WRA) and men conducted in all 9 regions and two city administration of Ethiopia. Serum Zn concentrations, measured using inductively coupled plasma-mass spectrometry (ICPMS), were compared to thresholds based on age, sex, fasting status, and time of blood collection, after adjusting for inflammation status. Median serum Zn concentration of the population was 57.5 μg dL^-1. Overall, it is estimated that 72% of the population was Zn deficient, with high prevalence in all demographic groups. Spatial statistical analysis showed that there was spatial dependence in Zn status of WRA at distances of up to 45 km. Zinc deficiency is spatially dependent over short distances. Although WRA in most areas are likely to be Zn deficient, prevalence of deficiency varies at regional scale and between rural and urban inhabitants, suggesting there is scope to explore drivers of this variation, prioritize nutritional interventions, and to design more representative surveillance programs.

Relationship of zinc status with depression and anxiety among elderly population

BACKGROUND & AIMS

Population aging is a global challenge. Old populations are prone to zinc deficiency. This study aimed to determine the association of zinc status with depression and anxiety among men and women aged 60+ years old.

METHODS

In this cross-sectional study, 297 elderly participants (144 males and 153 females) were studied. The dietary and serum zinc were assessed using a three-day dietary record and an auto-analyzer, respectively. Depression and anxiety were measured using Geriatric Depression Scale and Hamilton Anxiety Rating Scale, respectively. Chi-squared test was used to compare qualitative variables. Multiple logistic regression analysis was conducted to assess relationship between zinc status and depression/anxiety.

RESULTS

The total zinc deficiency based on serum values was 23.2%. Dietary intake of zinc in 72.4%of participants was less than of the Estimated Average Requirement (EAR). The total depression prevalence was 42.2%. Moreover, 52.5% of the participants suffered from anxiety. The odds of depression among participants in the third tertile of serum zinc concentration was 51% lower than those in the first tertile (OR = 0.49, CI = 0.25-0.96, p = 0.03). No significant relationship was found between zinc intake and depression. Furthermore, serum or dietary zinc levels were not related to anxiety.

CONCLUSIONS

This study showed a considerable zinc deficiency and depression/anxiety in the old population. A significant relation was found between serum zinc concentration and depression. Further surveys, especially cohort studies and clinical trials are needed to confirm these results.

Counter-intuitive plasma vitamin D and zinc status in HIV-1-infected adults with persistent low-level viraemia after treatment initiation: a pilot case-control study

Determinants of persistent low-level viraemia [PLLV, a viral load (VL) of between 50 and 500 copies/mL] have not been elucidated. In a case-control study, we evaluated the influence of micronutrients on PLLV in a population of 454 HIV-1 adults having initiated antiretroviral therapy (ART) between January 2007 and December 2011. Plasma levels of retinol (vitamin A), 25-OH vitamin D₂ + D₃, vitamin E and zinc were measured at ART initiation in cases (PLLV after 6 months of ART) and in controls (VL <50 copies/mL after 6 months). Cases and controls were matched for the CD4 cell count (±50/mm³) and ethnic origin. Intergroup differences in demographic, biological and treatment parameters and sunshine intensity at ART initiation were adjusted using a propensity score. A receiver operating characteristic (ROC) curve was used to assess intergroup differences in plasma micronutrient levels. Thirty-three of the 454 patients (7.3%) displayed PLLV (median VL: 92 copies/mL). Patients were predominantly male (89%), Caucasian (64%) and CDC stage C (25%). The median age was 38 years, the median initial VL was 5.2 log₁₀ copies/mL and the median CD4 count was 74/mm³. The 22 cases and matched controls were balanced in these respects, and had similar vitamin A/E levels. Two cases (9%) and 9 controls (41%) had a vitamin D level <10.3 ng/mL (p = 0.0015), and 2 cases (9%) and 10 controls (48%) had a zinc level <74.6 μg/dL (p = 0.04). Our results support in vitro studies suggesting that vitamin D favours HIV-1 replication and that HIV-1 is zinc-dependent. Wide-scale, prospective studies are required.

The influence of food consumption and socio-economic factors on the relationship between zinc and iron intake and status in a healthy population

OBJECTIVE

To examine Zn and Fe nutritional status of a healthy population by means of anthropometric, dietary and biochemical measurements and to investigate the relationship of usual Zn and Fe dietary intakes to Zn and Fe status. In addition, to examine the impact of food choices and socio-economic factors on Fe and Zn dietary intakes and status with the aim to identify groups at risk of dietary deficiency and suggest factors that may influence the status of these nutrients.

DESIGN

Food consumption was assessed by 24 h recall questionnaires. Twenty biochemical parameters were measured, of which Hb, haematocrit, erythrocyte count and plasma concentrations of Fe and Zn were directly related to Fe and Zn nutrition. The prevalence of study participants with inadequate micronutrient intakes was calculated using the Estimated Average Requirement cut-point method.

SETTING

Serbia, Europe.

SUBJECTS

Apparently healthy adults (25-65 years of age).

RESULTS

Mean daily Zn and Fe intakes were 9·1 mg and 11·6 mg for males and 7·3 mg and 9·4 mg for females, respectively. Five per cent of the study population had inadequate dietary Fe intake and 15-25 % had inadequate Zn intake. Lower Hb concentrations were measured in women with lower Zn intakes. No differences in Fe and Zn intakes and status among various socio-economic groups were observed, except for Fe intake between the low-income and affluent groups.

CONCLUSIONS

Regular follow-ups are needed to ensure that potential deficiencies of Zn and Fe do get recognized and addressed in a timely manner.

Maternal zinc deficiency and congenital anomalies in newborns

BACKGROUND

Zinc deficiency in pregnant women is common, especially in the third trimester of pregnancy. The available data, however, on the association between zinc deficiency and congenital malformations in the Iranian population are insufficient. The aim of this study was therefore to determine whether maternal serum zinc deficiency is associated with major congenital malformations in newborns.

METHODS

This descriptive, case-control study involved mothers of 80 neonates with congenital anomalies (study group) admitted to the Mofid Children's Hospital, Tehran, Iran. During the same period (2014 and 2015), serum zinc was measured in 80 mothers who had delivered normal newborns without congenital malformations (control group).

RESULTS

Mothers with serum zinc deficiency had a more than sevenfold risk of malformations in the fetus compared with mothers with normal serum zinc (OR, 7.013; 95%CI: 2.716-18.110). Newborns with malformation weighing ≤2500 g were associated with lower maternal serum zinc compared with the control group (P = 0.006).

CONCLUSIONS

There is an association between congenital malformation in newborns and maternal zinc deficiency.

Gene expression of the zinc transporter ZIP14 (SLC39a14) is affected by weight loss and metabolic status and associates with PPARγ in human adipose tissue and 3T3-L1 pre-adipocytes

Background

The expansion and function of adipose tissue are important during the development of insulin resistance and inflammation in obesity. Zinc dyshomeostasis is common in obese individuals. In the liver, zinc influx transporter ZIP14, affects proliferation and glucose metabolism but the role of ZIP14 in adipose tissue is still unknown. This study investigates ZIP14 gene expression in human adipose tissue before and after weight loss as well as the regulation of ZIP14 during early adipogenesis.

Methods

Fourteen obese individuals were investigated before and after a 10 week weight loss intervention and compared to 14 non-obese controls. Gene expressions of ZIP14 and peroxisome proliferator-activated receptor γ (PPARγ) were measured in subcutaneous adipose tissue and correlated with metabolic and inflammatory markers. Further, we investigated gene expression of ZIP14 and PPARγ during early adipogenesis of 3T3-L1 pre-adipocytes, together with an in silico analysis of PPARγ binding motifs in the promoter sequence of ZIP14.

Results

ZIP14 was down-regulated in obese individuals compared to non-obese controls (p = 0.0007) and was up-regulated after weight loss (p = 0.0005). Several metabolic markers of clinical importance, including body mass index, triglyceride, and insulin resistance, were inversely correlated with ZIP14. During early adipogensis an up-regulation of ZIP14 gene expression was found. PPARγ gene expression was positively correlated with the ZIP14 gene expression in both adipose tissue and during adipogenesis. However, in silico analysis revealed that the ZIP14 promoter does not contain PPARγ-binding motifs.

Conclusions

We hypothesize that ZIP14-mediated zinc influx might directly influence PPARγ activity and that ZIP14 may regulate expansion and function of adipose tissue and serve as a potential biomarker for metabolic stress.

Electronic supplementary material

The online version of this article (doi:10.1186/s40608-015-0076-y) contains supplementary material, which is available to authorized users.

Zinc involvement in opioid addiction and analgesia--should zinc supplementation be recommended for opioid-treated persons?

INTRODUCTION

Zinc chelators were shown to facilitate some opioid-withdrawal signs in animals. Zinc deficiency, which affects more than 15% the world's population, is also common among opioid consumers and opioid-treated animals exhibit misbalances of zinc distribution.

AIM

The present study focuses on how zinc ions interfere with opioid dependence/addiction and analgesia, trying to preliminary discuss if zinc supplementation in opioid-users should be recommended in order to reduce the risk of addiction.

METHODS

All relevant literature was searched up to April 2015. The search was performed using the term "zinc" plus combinations of following terms: "opioid receptors", "opioid" or representatives of this class, "addiction", "dependence", "analgesia", and "pain". Human, animal, in vitro studies and reviews were including.

RESULTS

Both human and animal studies revealed decreased serum zinc under opioid-administration conditions, attributed mainly to increased urinary elimination (humans) or redistribution (animals). Moreover, animal studies revealed decreased brain zinc levels in morphine-treated animals, with increased zinc hepatic levels, but also an enhancement of endogenous opioid system activity and a possible reduction of morphine withdrawal by zinc. In vitro studies revealed reduction of opioid ligands binding to receptors by zinc. However, the very few in vivo animal studies on opioid analgesia revealed controversial results, as zinc demonstrated clear analgesic effect, but zinc associated to opioids doesn't result in a potentiation of the analgesic effect.

CONCLUSION

Zinc dietary supplementation in patients treated with opioids for cancer-related chronic pain should be considered, due to the high incidence of zinc deficiency, also well-documented in opioid consumers. The low toxicity of orally-administered zinc also pleads for this idea. The main contra-argument to zinc administration in opioid-treated persons is related to the way zinc influences opioid-induced analgesia.

Maternal zinc deficiency during pregnancy elevates the risks of fetal growth restriction: a population-based birth cohort study

We investigated the association between maternal zinc level during pregnancy and the risks of low birth weight (LBW) and small for gestational age (SGA) infants in a large population-based birth cohort study. In this study, 3187 pregnant women were recruited. For serum zinc level, 2940 pregnant women were sufficient (≥56 μg/dL) and 247 deficient (<56 μg/dL). Of interest, 7.3% newborns were with LBW among subjects with low zinc level (RR: 3.48; 95% CI: 2.03, 5.96; P < 0.001). Adjusted RR for LBW was 3.41 (95% CI: 1.97, 5.91; P < 0.001) among subjects with low zinc level. Moreover, 15.0% newborns were with SGA among subjects with low zinc level (RR: 1.98; 95% CI: 1.36, 2.88; P < 0.001). Adjusted RR for SGA was 1.93 (95% CI: 1.32, 2.82; P < 0.001) among subjects with low zinc level. A nested case-control study within above cohort showed that maternal serum zinc level was lower in SGA cases as compared with controls. By contrast, maternal serum C-reactive protein, TNF-α and IL-8 levels were significantly higher in SGA cases than that of controls. Moreover, nuclear NF-κB p65 was significantly up-regulated in placentas of SGA cases as compared with controls. Taken together, maternal zinc deficiency during pregnancy elevates the risks of LBW and SGA infants.

SLC30A3 and SEP15 gene polymorphisms influence the serum concentrations of zinc and selenium in mature adults

Because of their numerous roles in several biological processes, zinc and selenium are the most commonly studied micronutrients in the elderly. Therefore, we hypothesized that the polymorphisms in the genes that are responsible for the transport of zinc and selenium may have a genotype-dependent effect on the serum concentration of these micronutrients. The objective of this study was to determine the effects of solute carrier family 30 member 3 (SLC30A3) and 15-kd selenoprotein (SEP15) polymorphisms on zinc and selenium concentrations, respectively, in the serum. This cross-sectional study included 110 individuals who were aged 50 years or older. Serum micronutrient concentrations were determined by flame atomic absorption spectrophotometry (for zinc) and by atomic absorption spectrophotometry with a graphite furnace (for selenium). The single-nucleotide polymorphisms, rs73924411 and rs11126936 of the SLC30A3 gene and rs5859, rs5854, and rs561104 of the SEP15 gene, were examined by real-time polymerase chain reaction. Regarding rs11126936, the serum zinc concentration was lower in CC homozygotes (0.75 ± 0.31 mg/L) than in A carriers (0.89 ± 0.28 mg/L, P = .016). Concerning rs561104, the serum selenium concentration was higher in CC homozygotes (5.65 ± 1.11 μg/dL) compared with T carriers (4.88 ± 1.25 μg/dL, P = .044). Our results demonstrate the influence of SLC30A3 and SEP15 gene polymorphisms on the serum concentrations of zinc and selenium, respectively. The effects of these associations should be further investigated to help elucidate the modes of action of trace elements and to identify biomarkers, which could ultimately define the optimal intake of these micronutrients at the molecular level. More research must be performed before the roles of these polymorphisms in the serum concentrations of zinc and selenium can be fully understood.

Socio-economic determinants of micronutrient intake and status in Europe: a systematic review

OBJECTIVE

To provide the evidence base for targeted nutrition policies to reduce the risk of micronutrient/diet-related diseases among disadvantaged populations in Europe, by focusing on: folate, vitamin B12, Fe, Zn and iodine for intake and status; and vitamin C, vitamin D, Ca, Se and Cu for intake.

DESIGN

MEDLINE and Embase databases were searched to collect original studies that: (i) were published from 1990 to 2011; (ii) involved >100 subjects; (iii) had assessed dietary intake at the individual level; and/or (iv) included best practice biomarkers reflecting micronutrient status. We estimated relative differences in mean micronutrient intake and/or status between the lowest and highest socio-economic groups to: (i) evaluate variation in intake and status between socio-economic groups; and (ii) report on data availability.

SETTING

Europe.

SUBJECTS

Children, adults and elderly.

RESULTS

Data from eighteen publications originating primarily from Western Europe showed that there is a positive association between indicators of socio-economic status and micronutrient intake and/or status. The largest differences were observed for intake of vitamin C in eleven out of twelve studies (5-47 %) and for vitamin D in total of four studies (4-31 %).

CONCLUSIONS

The positive association observed between micronutrient intake and socio-economic status should complement existing evidence on socio-economic inequalities in diet-related diseases among disadvantaged populations in Europe. These findings could provide clues for further research and have implications for public health policy aimed at improving the intake of micronutrients and diet-related diseases.

Zinc in depression: a meta-analysis

BACKGROUND

Zinc is an essential micronutrient with diverse biological roles in cell growth, apoptosis and metabolism, and in the regulation of endocrine, immune, and neuronal functions implicated in the pathophysiology of depression. This study sought to quantitatively summarize the clinical data comparing peripheral blood zinc concentrations between depressed and nondepressed subjects.

METHODS

PubMed, Cumulated Index to Nursing and Allied Health Literature, and PsycINFO were searched for original peer-reviewed studies (to June 2012) measuring zinc concentrations in serum or plasma from depressed subjects (identified by either screening or clinical criteria) and nondepressed control subjects. Mean (±SD) zinc concentrations were extracted, combined quantitatively in random-effects meta-analysis, and summarized as a weighted mean difference (WMD).

RESULTS

Seventeen studies, measuring peripheral blood zinc concentrations in 1643 depressed and 804 control subjects, were included. Zinc concentrations were approximately -1.85 µmol/L lower in depressed subjects than control subjects (95% confidence interval: [CI]: -2.51 to -1.19 µmol/L, Z17 = 5.45, p < .00001). Heterogeneity was detected (χ(2)17 = 142.81, p < .00001, I(2) = 88%) and explored; in studies that quantified depressive symptoms, greater depression severity was associated with greater relative zinc deficiency (B = -1.503, t9 = -2.82, p = .026). Effect sizes were numerically larger in studies of inpatients (WMD -2.543, 95% CI: -3.522 to -1.564, Z9 = 5.09, p < .0001) versus community samples (WMD -.943, 95% CI: -1.563 to -.323, Z7 = 2.98, p = .003) and in studies of higher methodological quality (WMD -2.354, 95% CI: -2.901 to -1.807, Z7 = 8.43, p < .0001).

CONCLUSIONS

Depression is associated with a lower concentration of zinc in peripheral blood. The pathophysiological relationships between zinc status and depression, and the potential benefits of zinc supplementation in depressed patients, warrant further investigation.

Potential roles of zinc in the pathophysiology and treatment of major depressive disorder

Incomplete response to monoaminergic antidepressants in major depressive disorder (MDD), and the phenomenon of neuroprogression, suggests a need for additional pathophysiological markers and pharmacological targets. Neuronal zinc is concentrated exclusively within glutamatergic neurons, acting as an allosteric modulator of the N-methyl D-aspartate and other receptors that regulate excitatory neurotransmission and neuroplasticity. Zinc-containing neurons form extensive associational circuitry throughout the cortex, amygdala and hippocampus, which subserve mood regulation and cognitive functions. In animal models of depression, zinc is reduced in these circuits, zinc treatment has antidepressant-like effects and dietary zinc insufficiency induces depressive behaviors. Clinically, serum zinc is lower in MDD, which may constitute a state-marker of illness and a risk factor for treatment-resistance. Marginal zinc deficiency in MDD may relate to multiple putative mechanisms underlying core symptomatology and neuroprogression (e.g. immune dysfunction, monoamine metabolism, stress response dysregulation, oxidative/nitrosative stress, neurotrophic deficits, transcriptional/epigenetic regulation of neural networks). Initial randomized trials suggest a benefit of zinc supplementation. In summary, molecular and animal behavioral data support the clinical significance of zinc in the setting of MDD.

Plasma zinc concentration increases within 2 weeks in healthy Senegalese men given liquid supplemental zinc, but not zinc-fortified wheat bread

The responsiveness of plasma zinc concentration to zinc fortification is uncertain. Our objective in this study was to determine whether plasma zinc concentration changes in response to consuming zinc-fortified foods or liquid zinc supplements. We conducted a 4-wk double-blind, randomized trial among 132 healthy Senegalese men ≥ 18 y. Participants received 1 of 4 interventions: 1) (control) 200 g/d of wheat bread fortified with iron and folic acid, but not zinc, and a liquid multivitamin supplement without zinc between meals; 2) (zinc supplement) the same bread and the same multivitamin supplement with 15 mg zinc as ZnSO(4) added; 3) (moderate zinc fortification) the same bread cofortified with 7.5 mg zinc as ZnO and the same multivitamin supplement without zinc; or 4) (high zinc fortification) the same bread cofortified with 15 mg zinc as ZnO and the same multivitamin supplement without zinc. Fasting blood samples were collected twice at baseline and at d 15 and 29 of the intervention. There was no significant interaction between group and study day (P = 0.11). However, at d 15, the mean change in plasma zinc concentration in the zinc-supplemented group was greater than in the placebo and fortification groups ( 0.72 μmol/L vs. -0.09 to 0.03 μmol/L; P = 0.05). At d 29 there were no significant group-wise differences. Across all time points, the zinc-supplemented group was the only group where plasma zinc concentration increased from baseline (P = 0.006). These results suggest that plasma zinc concentration may not be a sufficiently sensitive indicator to evaluate short-term responses to zinc fortification.

Structural basis for metal sensing by CnrX

CnrX is the metal sensor and signal modulator of the three-protein transmembrane signal transduction complex CnrYXH of Cupriavidus metallidurans CH34 that is involved in the setup of cobalt and nickel resistance. We have determined the atomic structure of the soluble domain of CnrX in its Ni-bound, Co-bound, or Zn-bound form. Ni and Co ions elicit a biological response, while the Zn-bound form is inactive. The structures presented here reveal the topology of intraprotomer and interprotomer interactions and the ability of metal-binding sites to fine-tune the packing of CnrX dimer as a function of the bound metal. These data suggest an allosteric mechanism to explain how the complex is switched on and how the signal is modulated by Ni or Co binding. These results provide clues to propose a model for signal propagation through the membrane in the complex.