Plasma Zinc Research Articles

Daily preventive zinc supplementation increases the antibody response against pathogenic Escherichia coli in children with zinc insufficiency: a randomised controlled trial

Zinc deficiency impairs the antibody-mediated immune response and is common in children from lower-income countries. This study aimed to investigate the impact of different zinc supplementation regimens (7, 10 or 20 mg/day elemental zinc)—therapeutic dispersible zinc tablets (TZ), daily multiple micronutrient powder (MNP), daily preventive zinc tablets (PZ) and placebo powder (control)—and compare between baseline and endline antibody production against pathogenic Escherichia coli in Laotian children (aged 6–23 months). Fifty representative plasma samples of each treatment group were randomly selected from 512 children to determine anti-E. coli IgG antibody levels and avidity. Of the 200 children, 78.5% had zinc deficiency (plasma zinc concentration < 65 µg/dL) and 40% had anaemia before receiving zinc supplementation. aAfter receiving the TZ, MNP or PZ regimen, the plasma anti-E. coli IgG levels were significantly increased compared with baseline; the effect on the antibody level was more pronounced in children with zinc deficiency. Interestingly, there was increased anti-E. coli IgG avidity in the control and PZ groups. This study suggests that PZ might be the optimal zinc supplementation regimen to increase both the quantity and quality of antibody responses in children with zinc deficiency. Clinical trial registration: https://clinicaltrials.gov/ct2/show/NCT02428647 (NCT02428647, 29/04/2015).

Effects of Different Concentrations of BSA on In Vitro Corrosion Behavior of Pure Zinc in Artificial Plasma

When medical metallic materials are implanted in the body and come into contact with the body fluid environment, proteins will be rapidly adsorbed on the surface and affect the corrosion process of the material. Currently, there is no uniform understanding of the effect of protein adsorption on the corrosion behavior of materials due to the limitations of the nature of metal materials, protein concentrations, and different media environments. The effect of various bovine serum albumin (BSA) concentrations in artificial plasma (AP) on the corrosion behavior of pure Zn during 14 days of immersion was investigated in this research. The corrosion rate of pure Zn was slowed down by the addition of BSA, and the decelerating effect of lower protein concentration on the corrosion rate of Zn was more significant in the initial stage of immersion. With prolonging the immersion time, the corrosion rate of pure Zn in different media slowed down and stabilized, and the corrosion rates of pure Zn showed a decreasing trend with an increase of BSA concentration. Furthermore, the Langmuir adsorption isotherm model was utilized to study the relationship between the BSA concentration and corrosion behavior of pure Zn and to analyze the role of proteins in the degradation mechanism of pure Zn. This work could be useful for further exploration of potential clinical applications of zinc alloys.

Zinc Fortification: Current Trends and Strategies

Zinc, through its structural and cofactor roles, affects a broad range of critical physiological functions, including growth, metabolism, immune and neurological functions. Zinc deficiency is widespread among populations around the world, and it may, therefore, underlie much of the global burden of malnutrition. Current zinc fortification strategies include biofortification and fortification with zinc salts with a primary focus on staple foods, such as wheat or rice and their products. However, zinc fortification presents unique challenges. Due to the influences of phytate and protein on zinc absorption, successful zinc fortification strategies should consider the impact on zinc bioavailability in the whole diet. When zinc is absorbed with food, shifts in plasma zinc concentrations are minor. However, co-absorbing zinc with food may preferentially direct zinc to cellular compartments where zinc-dependent metabolic processes primarily occur. Although the current lack of sensitive biomarkers of zinc nutritional status reduces the capacity to assess the impact of fortifying foods with zinc, new approaches for assessing zinc utilization are increasing. In this article, we review the tools available for assessing bioavailable zinc, approaches for evaluating the zinc nutritional status of populations consuming zinc fortified foods, and recent trends in fortification strategies to increase zinc absorption.

Excess dietary zinc drives a Cushing's-like syndrome in ovariectomized mice – Implications for postmenopausal obesity

Postmenopausal women have an increased risk of obesity, but the underlying cause is not clear. We unexpectedly found that excess dietary zinc induced severe obesity and a Cushing's-like syndrome without increased food intake in ovariectomized (Ovx) but not in sham-operated mice. Zinc accumulated in the adrenal glands and inhibited adrenal 17,20-lyase activity and steroid synthesis. As adrenal steroids are the only source of estrogen in Ovx mice, estrogen deficiency induced adrenal hyperplasia, glucocorticoid overproduction, and consequent development of a Cushing's-like syndrome. Adrenal steroid supplementation prevented the effects of zinc. Plasma zinc was positively correlated with cortisol level and negatively correlated with the levels of adrenal steroids and estrogen in obese postmenopausal women. The finding of a link between dietary zinc, estrogen deficiency, and postmenopausal obesity, implies that postmenopausal obesity might be prevented by supplementation with a adrenal steroid and avoiding excess dietary zinc.

Metabolic linkages between zinc exposure and lung cancer risk: A nested case-control study.

Epidemiologic studies have suggested that elevated concentrations of zinc are associated with a decreased risk of lung cancer, but the underlying mechanisms remain to be investigated. The metabolites are highly sensitive to environmental stress, which will help to reveal the linkages between zinc exposure and lung cancer risk. We designed a nested case-control study including 101 incident lung cancer cases and 1:2 age- and sex-frequency-matched 202 healthy controls from the Dongfeng-Tongji (DFTJ) cohort. Their plasma level of zinc was determined by using inductively coupled plasma-mass spectrometry (ICP-MS) and plasma profiles of metabolites were detected by using an untargeted metabolomics approach. The generalized linear models (GLM) were applied to assess the associations of plasma zinc with metabolites, and the mediation effects of zinc-related metabolites on zinc-lung cancer association were further testified. The concentrations of 55 metabolites had linear dose-response relationships with plasma zinc at a false discovery rate (FDR) < 0.05, among which L-proline, phosphatidylcholine (PC, 34:2), phosphatidylethanolamine (PE, O-36:5), L-altrose, and sphingomyelin (SM, 40:3) showed different levels between lung cancer cases and healthy controls (fold change = 0.92, 0.95, 1.07, 0.90, and 1.08, respectively, and all P < 0.05). The plasma concentration of SM(40:3) was negatively associated with incident risk of lung cancer [OR(95%CI) = 0.71(0.55, 0.91), P = 0.007] and could mediate 41.7% of the association between zinc and lung cancer risk (P = 0.004). Moreover, compared to the traditional factors, addition of SM(40:3) exerted improved prediction performance for incident risk of lung cancer [AUC(95%CIs) = 0.714(0.654, 0.775) vs. 0.663(0.600, 0.727), P = 0.030]. Our findings revealed metabolic profiles with zinc exposure and provide new insight into the alternations of metabolites underpinning the links between zinc exposure and lung cancer development.

Investigating hypozincemia and validity of plasma zinc measurements in infected patients

Hypozincemia is a well-known phenomenon in patients with infection caused by the activation of the acute phase response (APR). Zn status is still based upon plasma Zn levels in venous blood samples. Recent trials have questioned the validity of this measurement in infected patients. The aim of this study was to assess plasma levels of Zn, albumin and Zinc-binding capacity in patients during and following infection. Furthermore, to assess if an assay for albumin-corrected Zn could potentially replace or add knowledge to existing tools for assessment of Zinc-status. A prospective clinical observational trial was conducted. Associations between P-Zn, -Albumin, -Albumin-corrected Zn and Zn binding capacity were analyzed. Analyzes were based upon two venous blood samples drawn during and following infection, respectively. Twenty-three patients admitted to a medical ward showing paraclinical signs of infection were included in the study. Significantly lower levels of Zn and albumin were found during infection compared with the levels post-infection. These findings corresponded to the changes found in Zn binding capacity. About 52% of patients were deemed Zn deficient by plasma Zn levels during infection but after applying the correction for P-Albumin, all patients were found to be within normal ranges of Zn levels. Furthermore, we found no statistically significant difference between albumin-corrected Zn during infection and P-Zn post-infection. The new assay was found to accurately estimate the ‘true’ Zn levels in infected patients. Based on our findings, we propose albumin-corrected P-Zn as a promising new tool, which may result in more precise diagnostics and treatment.

Investigation of Biomarkers in Sub-Acute Hepatorenal Toxicity against Bulk and Zinc Oxide Nanoparticles Exposed Mice

Zinc oxide nanoparticles have been utilized and produced at a very large scale due to their wide range of applications. Nevertheless, its toxicity is one of the concerns addressed by various researchers. Widely used methods of measuring plasma zinc have poor sensitivity and impaired specificity. Currently, there is no specific biomarker for determination of excess zinc inside our body is explored well. Furthermore, it is vital to know the toxic effects of zinc oxide nanoparticles and their bulk counterparts at early exposure level on human health due to day to day increased use of zinc oxide nanoparticles in various applications. In current study we investigate the kidney and liver as the primary target organs for toxicity and their oxidative stress parameters. Twenty-four male mice were divided into three groups(n=8). Control (group I) served as vehicle control; group II:50mg/kg ZnO (bulk) and group III:ZnO NPs (50mg/kg nano). The mice were sacrificed after 14 days exposure, liver and kidney tissue toxicity biomarkers were performed. Our results demonstrate increased levels of GPx, metallothionein, GST, and decrease level of ceruloplasmin, GSH:GSSG ratio in bulk ZnO administered animals. The acute kidney toxicity was further confirmed by increased levels of their biomarkers i.e. Kim-1 and Clusterin. The levels of serum cytokines and caspase were also analyzed. Hence, this study investigated the comparative effect of early exposure of zinc oxide nanoparticles (nZnO) and its bulk form and we conclude that at 50mg/kg b.wt dose, ZnO NPs is comparatively safe to bulk ZnO.

Relationship between zinc-related nutritional status and the progression of multiple sclerosis

BackgroundMultiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system. ObjectiveTo investigate plasma and erythrocyte zinc status and its relationship to MS. MethodsCross-sectional study, including 98 participants, distributed in groups: case (MS, n = 49), diagnosed with MS and control (n = 49), matched by age and sex with the case group. Zinc was analyzed by flame atomic absorption spectrophotometry, and superoxide dismutase (SOD) activity by spectrophotometry. ResultsMean plasma zinc was 94.6 (22.1) μg/dL for MS patients and 81.5 (31.3) μg/dL for control group, with statistical difference (p = 0.023). The mean erythrocyte zinc was 83.6 (41.6) µg/gHb for case group and 72.6 (31.5) µg/gHb for control. Erythrocyte SOD activity was above reference values, significantly different for MS patients (p = 0.003). There was a significant direct correlation between erythrocyte zinc and SOD (r = 0.835; p < 0.001). SOD showed inverse correlation with MS outbreaks (r = -0.317; p = 0.027). ConclusionPatients with MS have normal plasma and elevated erythrocyte zinc. Erythrocyte zinc showed positive correlation with SOD, which correlated inversely to outbreaks.

Association of SNPs in zinc transporter genes on seminal plasma zinc levels in humans.

This study is to examine the effects of single nucleotide polymorphisms (SNPs) of SLC30A and SLC39A on seminal plasma zinc concentration. Blood and seminal plasma samples were collected from outpatients. SNPs of zinc transporters were analyzed by next Generation sequencing technology, and seminal plasma zinc concentration were determined by inductively coupled plasma optical emission spectrometry. Our date showed nine SNPs (SLC30A8 rs2466295, rs2466294, SLC30A10 c.-160C>G, SLC39A8 rs9331, rs9705, rs151392, rs151393, SLC39A11 rs9912126, SLC39A14 rs1051708) were significantly associated with seminal plasma zinc concentration, and 14 SNPs (SLC30A8 rs2466295, rs2466294, SLC30A10 c.-160C>G, SLC39A6 rs148550301, SLC39A8 rs9331, rs9705, rs151392, rs151393, SLC39A11 rs9912126, rs61736066, rs36041371 and SLC39A14 rs1051708, rs76963096, rs17060854) were found to be significantly associated with total zinc per ejaculate. The seminal plasma zinc concentrations and total zinc per ejaculate were associated with the number of SNPs, and decreased significantly when five SNPs (SLC39A8 rs9331, rs9705, rs151392, rs151393 and SLC39A14 rs1051708) were a combination of homozygous genotype. Our findings suggest that different zinc transporter SNPs may significantly affect seminal plasma zinc levels.

Possible relationship between poor skin disorders prognosis and serum zinc level: A narrative review.

Zinc is a trace nutrient essential for the normal growth and development of human body. The main aim was to evaluate the significant association between measured zinc status in relation to different skin disorders and their severity. PubMed®, Google® Scholar™ and Cochrane© Reviews databases were searched for studies from January 2017 to June 2021, using the terms; zinc serum levels, zinc plasma levels and different dermatosis in the review, only human studies in English language were reviewed and the studies designs were controlled, cross sectional, observational and analytic types. A total of forty-eight research studies were included in this review. All studies have evaluated serum zinc in skin diseases including psoriasis, atopic dermatitis, pityriasis alba, androgenetic alopecia areata, telogen effluvium, vitiligo, melasma, acne, seborrheic dermatitis and hidradenitis suppuritiva. It was found that 33 studies had validated statistically significant differences in serum zinc levels between patients and controls. There is a predominance of low serum zinc levels in all the dermatoses reviewed. The clinical significance of this finding highlights the possible value, and need to investigate, the use of Zinc supplementation as an adjuvant therapy in the management of chronic inflammatory and autoimmune skin diseases proven to manifest altered zinc levels.

Assessment of Joint Impact of Iodine, Selenium, and Zinc Status on Women's Third-Trimester Plasma Thyroid Hormone Concentrations

ABSTRACTBackgroundIodine is essential for synthesizing thyroid hormones, but other micronutrients are also required for optimal thyroid function. However, there is a lack of data on combined micronutrient status in relation to thyroid hormones in pregnancy.ObjectivesWe aimed to assess the joint associations of iodine, selenium, and zinc status with plasma concentrations of thyroid hormones and thyroid-stimulating hormone (TSH) in pregnancy.MethodsWe included 531 pregnant women (aged 22–40 y) participating in a Swedish birth cohort who provided blood and spot urine samples in gestational weeks 27–33 (mean: 29). Associations of urinary iodine concentration (UIC), plasma selenium concentration, and plasma zinc concentration (measured by inductively coupled plasma mass spectrometry) with plasma hormone concentrations [total and free thyroxine (tT4, fT4), total and free triiodothyronine (tT3, fT3), and TSH] were explored with Bayesian kernel machine regression (BKMR; n = 516; outliers excluded) and multivariable-adjusted linear regression (n = 531; splined for nonlinear associations).ResultsMedian (IQR) micronutrient concentrations were 112 μg/L (80–156 μg/L) for UIC, 67 μg/L (58–76 μg/L) for plasma selenium, and 973 μg/L (842–1127 μg/L) for plasma zinc; the former 2 median values were below recommended concentrations (150 μg/L and 70 μg/L, respectively). Mean ± SD TSH concentration was 1.7 ± 0.87 mIU/L, with 98% < 4 mIU/L. BKMR showed a positive trend of joint micronutrient concentrations in relation to TSH. Plasma zinc was most influential for all hormones but tT3, for which plasma selenium was most influential. In adjusted linear regression models, zinc was positively associated with tT4, tT3, and TSH, and <1200 μg/L also with fT4 and fT3. Selenium was inversely associated with fT3, and <85 μg/L with tT3.ConclusionsPregnant women's plasma TSH concentrations in the early third trimester increased with increasing joint status of iodine, selenium, and zinc. Zinc and selenium were more influential than iodine for the hormone concentrations. Multiple micronutrients need consideration in future studies of thyroid hormone status.

Relationship between indicators of oxidative stress and idiopathic infertility in men

Male infertility is a major health problem worldwide. According to a study of the WHO and the European Association of Urologists, the incidence of infertility is increasing worldwide. The male factor causes up to 50% of all cases of infertility in married couples and approximately 7% of men worldwide suffer from infertility. No cause can be found in approximately 30% of infertile men, and these cases are called idiopathic infertility. In many such cases, oxidative stress is believed to be the main causative factor. Oxidative stress, which is characterized by an imbalance between the production of reactive oxygen species and the antioxidant defense system, which is responsible for their neutralization, leads to damage to many cellular structures, especially phospholipids of cell membranes. The study is aimed at studying the adverse effect of lipid peroxidation on spermatogenesis in idiopathic male infertility. The study was conducted on the sperm of 56 men with normozoospermia and 30 men with oligoasthenozoospermia. The levels of malondialdehyde, zinc, fructose, NO-synthase activity and glutathione peroxidase (GP) in seminal plasma were correlated with sperm count and motility. Ejaculate malondialdehyde and NO-synthase activity were significantly higher, while zinc, fructose and GP were significantly lower in oligoasthenospermic than in normospermic men (p&lt;0.001). A 1.8-fold decrease in the level of fructose in the spermogram of patients of group oligoasthenospermia, compared to the data of normozoospermic men correlated with processes of impaired motility and viability of spermatozoa. This was confirmed by the data obtained in the scientific work, in the form of a statistically significant difference in the average indicator of the quantitative content of fructose in the studied groups of patients. In particular, we found a positive correlation between the fructose content in the ejaculate and sperm motility (r=0.69), as well as a positive correlation between fructose content and the number of spermatozoa in the ejaculate (r=0.53). There was a significant negative correlation between malondialdehyde and NO-synthase with sperm count and motility in oligoasthenospermia. Elevated levels of malondialdehyde, NO-synthase in sperm, and decreased levels of zinc and GP in oligoasthenospermia may be responsible for impaired sperm membrane integrity and play a role in sperm DNA damage. The positive correlation of zinc with sperm count and sperm motility indicates an important role of zinc in spermatogenesis. Thus, these parameters may be useful in determining the fertilization potential of sperm in the diagnosis, prognosis and treatment of male infertility, especially idiopathic infertility. Keywords: sperm plasma, malondialdehyde, glutathione peroxidase, NO-synthase, zinc, fructose.

Association of Zinc Concentration in Seminal Plasma and Blood with Several Parameters of Semen in Infertile Males

Objective: To evaluate the concentration of zinc inthe blood and seminal plasma with semen parameters between fertile and infertile males Methodology: This prospective study was carried out in the Department of Biochemistry, Hayatabad medical complex, Peshawar. Fifty (50)infertile males, not receiving any treatment and had regularintercourse for 1 yearaged 25-45 years were selected from HMC. They were divided into 35oligospermia and 15 azoospermic. 35 fertile males were nominatedamongthe overallresidents and were taken as the control group after their semen analysis was taken as normozoospermic. According to WHO criteria semen is analyzed. With the help of 5br Serum and seminal plasma zinc were estimated. Result: There was a significant difference found in serum and seminal levels of zinc in normozoospermic, oligospermia (p less than 0.05), and azoospermic (p-value less than 0.05) individuals. The correlation of seminal plasma zinc with sperm counts showed a positive association with the count of sperm and a negative association with motility of sperm in normozoospermic/oligospermia and a negative association of concentration with pH, and volume, WBC in all groups. No association was found with the morphology of sperm. Conclusion: It has been concluded that zinc interfered with fertility by having a considerable impact on many semen parameters. It suggests that measuring seminal plasma zinc could be useful for diagnosing and treating male infertility.

Alterations in metal homeostasis occur prior to canonical markers in Huntington disease

The importance of metal biology in neurodegenerative diseases such as Huntingtin Disease is well documented with evidence of direct interactions between metals such as copper, zinc, iron and manganese and mutant Huntingtin pathobiology. To date, it is unclear whether these interactions are observed in humans, how this impacts other metals, and how mutant Huntington alters homeostatic mechanisms governing levels of copper, zinc, iron and manganese in cerebrospinal fluid and blood in HD patients. Plasma and cerebrospinal fluid from control, pre-manifest, manifest and late manifest HD participants were collected as part of HD-Clarity. Levels of cerebrospinal fluid and plasma copper, zinc, iron and manganese were measured as well as levels of mutant Huntingtin and neurofilament in a sub-set of cerebrospinal fluid samples. We find that elevations in cerebrospinal fluid copper, manganese and zinc levels are altered early in disease prior to alterations in canonical biomarkers of HD although these changes are not present in plasma. We also evidence that CSF iron is elevated in manifest patients. The relationships between plasma and cerebrospinal fluid metal are altered based on disease stage. These findings demonstrate that there are alterations in metal biology selectively in the CSF which occur prior to changes in known canonical biomarkers of disease. Our work indicates that there are pathological changes related to alterations in metal biology in individuals without elevations in neurofilament and mutant Huntingtin.

EFFECT OF SUSTAINED-RELEASE TRACE ELEMENT RUMINAL BOLUS ON PLASMA TRACE MINERAL PROFILES IN CAPTIVE BLESBOK ANTELOPES (DAMALISCUS PYGARGUS PHILLIPSI).

Nutritional deficiencies in mineral metabolism have been described or suspected in managed and wild ungulate populations. In blesboks (Damaliscus pygargus phillipsi), clinical signs of copper deficiencies have been described in the wild as well as in captivity. Plasma concentrations of cobalt (Co), copper (Cu), iodine (I), manganese (Mn), selenium (Se), and zinc (Zn) were measured over a 6-mon period by inductively coupled plasma mass spectrometry in two groups of five apparently healthy blesboks from a single zoological collection. The control group did not receive any treatment, whereas animals from the treatment group were given an oral drench in October with two sustained-release trace element ruminal boluses (Oligovet ovin-caprin 6 g bolus, Vetalis, 16100 Château Bernard, France). Plasma samples were obtained prior to the start of treatment (October) and in November, February, and April following treatment. No significant differences were found between treatment and control groups for any of the measured minerals over the course of the study. The plasma concentrations of Co, Cu, Se, and Zn were significantly different (P < 0.05) over time for all individuals, but this effect could not be linked to a change in the diet or husbandry. Copper plasma values fluctuated between deficient and normal ranges for cattle. Zinc plasma values were within a range consistent with deficiency in cattle. The great variability of these results should prompt caution in the interpretation of the efficacy of oral trace mineral intake or the expected effect of a dietary modification on trace mineral status based on plasma values.

The Impact of Zinc Supplementation on Critically Ill Patients With Acute Kidney Injury: A Propensity Score Matching Analysis.

BackgroundZinc is an essential trace element involved in multiple metabolic processes. Acute kidney injury (AKI) is associated with low plasma zinc, but outcomes with zinc supplementation in critically ill patients with AKI remain unknown. Our objective was to investigate the effectiveness of zinc supplementation in this patient population.MethodsCritically ill patients with AKI were identified from the Medical Informative Mart for Intensive Care IV database. Prosperity score matching (PSM) was applied to match patients receiving zinc treatment to those without zinc treatment. The association between zinc sulfate use and in-hospital mortality and 30-day mortality, need for renal replacement therapy (RRT), and length of stay was determined by logistic regression and Cox proportional hazards modeling.ResultsA total of 9,811 AKI patients were included in the study. PSM yielded 222 pairs of patients who received zinc treatment and those who did not. Zinc supplementation was associated with reduced in-hospital mortality (HR = 0.48 (95% CI: 0.28, 0.83) P = 0.009) and 30-day mortality (HR = 0.51 (95% CI, 0.30, 0.86) P = 0.012). In the subgroup analysis, zinc use was associated with reduced in-hospital mortality in patients with stage 1 AKI and those with sepsis.ConclusionsZinc supplementation was associated with improved survival in critically ill patients with AKI. The supplementation was especially effective in those with stage 1 AKI and sepsis. These results need to be verified in randomized controlled trials.

Epigenome–wide DNA methylation signature of plasma zinc and their mediation roles in the association of zinc with lung cancer risk

Essential trace element zinc is associated with decreased lung cancer risk, but underlying mechanisms remain unclear. This study aimed to investigate role of DNA methylation in zinc-lung cancer association. We conducted a case-cohort study within prospective Dongfeng-Tongji cohort, including 359 incident lung cancer cases and a randomly selected sub–cohort of 1399 participants. Epigenome-wide association study (EWAS) was used to examine association of plasma zinc with DNA methylation in peripheral blood. For the zinc-related CpGs, their mediation effects on zinc-lung cancer association were assessed; their diagnostic performance for lung cancer was testified in the case-cohort study and further validated in another 126 pairs of lung cancer case-control study. We identified 28 CpGs associated with plasma zinc at P < 1.0 × 10−5 and seven of them (cg07077080, cg01077808, cg17749033, cg15554270, cg26125625, cg10669424, and cg15409013 annotated to GSR, CALR3, SLC16A3, PHLPP2, SLC12A8, VGLL4, and ADAMTS16, respectively) were associated with incident risk of lung cancer. Moreover, the above seven CpGs were differently methylated between 126 pairs of lung cancer and adjacent normal lung tissues and had the same directions with EWAS of zinc. They could mediate a separate 7.05%∼22.65% and a joint 29.42% of zinc-lung cancer association. Compared to using traditional factors, addition of methylation risk score exerted improved discriminations for lung cancer both in case-cohort study [area under the curve (AUC) = 0.818 vs. 0.738] and in case-control study (AUC = 0.816 vs. 0.646). Our results provide new insights for the biological role of DNA methylation in the inverse association of zinc with incident lung cancer.

Physiological Response of Lamb to Zinc Supplementation during Heat Stress Season

The aim of this research was to evaluate the role of zinc supplementation on the reduction of heat stress in local lambs during hot season. In the current experiment, twenty-seven lambs were housed indoor in individual pens (1.50 × 1.30m). Zinc was added to the fresh drinking water in three different levels namely T1 (0 mg Zn/day), T2 (36 mg Zn/day) and T3 (72 mg Zn/day). Serum zinc (zinc; µmol/L), Alkaline phosphate (ALP; U/I), Alanine amino transferase (ALT; U/I), Aspartate amino transferase (AST; U/I), Creatine kinase (CK; U/I), Blood glucose level (mg/dl), Triiodothyronine hormone (T3; ng/ml), Thyroxin hormone (T4; ng/ml) were measured once per week. Zinc supplementation results show significant decrease in Aspartate amino transferase (AST) in (week 4), and Creatine kinase (CK) at (week 6) in T1group. Also zinc supplementation decreased triiodothyronine hormone (T3), and thyroxin hormone (T4) in (week 4). Whereas serum zinc level and alkaline phosphate (ALP) increased, also blood glucose level increased significantly in T2 (week 5) when the lambs were supplemented with 36 mg / zinc/ day. However, no effect of zinc supplementation was recorded on lamb serum ALT. Zinc supplementation was effective to increase blood plasma zinc concentration, ALP and kept the level of T4 from reduction during heat stress. However, zinc supplementation failed to keep the level of T3 from reduction during heat stress. This could be due to the type of zinc that was supplemented in the current experiment was inorganic which is less bioavailable than organic zinc

Environmental metal exposure, seminal plasma metabolome and semen quality: Evidence from Chinese reproductive-aged men

Environmental metal exposure has been associated with decreasing semen quality, but the effects of multiple metal exposure on seminal plasma metabolome remain obscure. In this study, semen and repeated urine samples from 551 volunteers were collected in Wuhan City. Heavy metals and trace elements were measured using inductively coupled plasma mass spectrometer, and seminal plasma metabolomes were acquired using liquid chromatography coupled with high-resolution mass spectrometry. Weighted gene co-expression network analysis showed more than half of the seminal plasma metals were associated with specific metabolite modules, whereas only a few urine metals presented weak associations, indicating that seminal plasma may be an ideal biological sample for male reproductive biomarker discovery and exposure risk assessment. Seminal plasma zinc (Zn) and selenium (Se) concentrations were significantly associated with 22 metabolites (e.g., glycerophospholipids, acyl-carnitines and amino acid derivatives). Among these metabolites, acyl-carnitines were positively associated with semen quality and sperm concentration. Moreover, acyl-carnitines were associated with both Zn and Se exposure, indicating the potential role of carnitine pathway in their toxicity mechanism. Our findings suggest that seminal plasma metabolome connects Zn and Se exposure and sperm concentrations in Chinese men of reproductive age.

Nitric Oxide Mobilizes Intracellular Zn2+ via the GC/cGMP/PKG Signaling Pathway and Stimulates Adipocyte Differentiation.

Plasma and tissue zinc ion levels are associated with the development of obesity. Previous studies have suggested that zinc ions may regulate adipocyte metabolism and that nitric oxide (NO) plays a pivotal role in the regulation of adipocyte physiology. Our previous study showed that chronic NO deficiency causes a significant decrease in adipose tissue mass in rats. Studies also suggested that zinc ions play an important modulatory role in regulating NO function. This study aims to explore the role of zinc ions in NO-regulated adipocyte differentiation. We hypothesized that NO could increase intracellular Zn2+ level and then stimulate adipocyte differentiation. ZnCl2 and the NO donor, NONOate, were used to explore the effects of Zn2+ and NO on adipocyte differentiation. Regulatory mechanisms of NO on intracellular Zn2+ mobilization were determined by detection. Then, Zn2+-selective chelator TPEN was used to clarify the role of intracellular Zn2+ on NO-regulated adipocyte differentiation. Furthermore, the relationship between adipocyte size, Zn2+ level, and NOS expression in human subcutaneous fat tissue was elucidated. Results showed that both ZnCl2 and NO stimulated adipocyte differentiation in a dose-dependent manner. NO stimulated intracellular Zn2+ mobilization in adipocytes through the guanylate cyclase (GC)/cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) pathway, and NO-stimulated adipocyte differentiation was Zn2+-dependent. In human subcutaneous adipose tissue, adipocyte size was negatively correlated with expression of eNOS. In conclusion, NO treatment stimulates intracellular Zn2+ mobilization through the GC/cGMP/PKG pathway, subsequently stimulating adipocyte differentiation.