Zinc and smoking habits in the setting of hypertension in a Spanish populations

Plasma metallomics reveals potential biomarkers and insights into the ambivalent associations of elements with acute myocardial infarction

Acute myocardial infarction (AMI) is a leading cause of mortality and morbidity worldwide. Using a validated and efficient ICP-MS/MS-based workflow, a total of 30 metallomic features were profiled in a study comprising 101 AMI patients and 66 age-matched healthy controls. The metallomic features include 12 essential elements (Ca, Co, Cu, Fe, K, Mg, Mn, Na, P, S, Se, Zn), 8 non-essential/toxic elements (Al, As, Ba, Cd, Cr, Ni, Rb, Sr, U, V), and 10 clinically relevant element-pair product/ratios (Ca/Mg, Ca×P, Cu/Se, Cu/Zn, Fe/Cu, P/Mg, Na/K, Zn/Se). Preliminary linear regression with feature selection confirmed smoking status as a predominant determinant for the non-essential/toxic elements, and revealed potential routes of action. Univariate assessments with adjustments for covariates revealed insights into the ambivalent relationships of Cu, Fe, and P with AMI, while also confirming cardioprotective associations of Se. Also, beyond their roles as risk factors, Cu and Se may be involved in the response mechanism in AMI onset/intervention, as demonstrated via longitudinal data analysis with 2 additional time-points (1-/6-month follow-up). Finally, based on both univariate tests and multivariate classification modelling, potentially more sensitive markers measured as element-pair ratios were identified (e.g., Cu/Se, Fe/Cu). Overall, metallomics-based biomarkers may have utility for AMI prediction.

Smoking is associated with altered serum and hair essential metal and metalloid levels in women

The objective of the study was to evaluate the association between smoking and essential metal (Co, Cr, Cu, Fe, Mn, V, Zn) and metalloid (Se) levels in hair and serum of adult women using inductively coupled plasma-mass spectrometry (ICP-MS). In this cross-sectional study, a total of 344 women 20-70 years old including 199 smokers and 145 non-smoking women were enrolled. Serum Cu, Fe, and Zn levels in smoking women were found to be 6%, 8%, and 3% lower of levels in non-smokers, respectively. In contrast, circulating Mn, V, and especially Cr concentrations in smoking women exceeded the respective values in non-smoking women by 5%, 14%, and 54%. Hair Fe and Se levels in smoking women were 17% and 23% lower as compared to non-smoking controls, respectively. In multiple regression models, smoking severity was inversely associated with serum and hair Se concentrations, whereas the relationship to serum and hair Cr was positive. In addition, serum Zn and hair Fe levels were found to be inversely associated with the number of cigarettes per day. These findings hypothesize that health hazards of smoking may be at least in part be mediated by alteration in essential metal and metalloid metabolism.

On-line determination of soluble Zn content and size of the residual fraction in PM2.5 incubated in various aqueous media

Transition metals in airborne particulate matter, especially those with aerodynamic diameters no more than 2.5 μm (PM_2.5), have attracted considerable attention due to their potential environmental and human health risks. However, determination of these potential risks requires comprehensive knowledge of their dissolution behavior and residual size in aqueous media. Herein, we describe an analytical method for on-line determination of the soluble fraction of Zn as a model transition metal and the size of residual PM_2.5 using hollow fiber flow field-flow fractionation (HF5) coupled with UV-vis absorption spectroscopy and inductively coupled plasma optical emission spectroscopy. HF5 was directly applied on the incubated samples in pure water (PW), simulated natural water (SNW), and simulated lung fluid (SLF) due to its efficient in-line filtration and excellent fractionation resolution. Firstly, the potential of the proposed method (under optimized conditions) for size characterization was assessed against commercial silica microparticles, and results in good agreement with manufacturer and scanning electron microscopy values were obtained. The accuracy of quantification of soluble Zn in various media was then validated using a standard reference material in terms of satisfactory recoveries compared with the reference values. For the real PM_2.5 samples collected from different sites in Beijing, China, the soluble Zn percentages in PW, SNW, and SLF were within 15.4-16.7%, 10.6-12.7%, and 43.1-46.9%, respectively, with the amount of particles smaller than ~10 nm released from PM_2.5 increasing in the order of SNW < PW < SLF. The proposed HF5-based method provides a powerful and efficient tool for the quantification of soluble transition metal fractions and size characterization of residual particles with reduced analysis times, thus possessing great promise in real-time tracking of the transformation of PM_2.5 in environmental and physiological media and in risk assessment.

The association of serum zinc and copper with hypertension: A meta-analysis

OBJECTIVE

The association of serum zinc (Zn), copper (Cu) with the risk of hypertension (HT) remains controversial. Therefore, we conducted a meta-analysis to explore the relationships.

METHODS

We searched relevant literatures on PubMed and Web of Science up to September 2018. Pooled standard mean difference (SMD) with corresponding 95% confidence interval (CI) was calculated by random effects model.I² was used to evaluate heterogeneity among studies.

RESULTS

25 articles of serum Zn and 22 articles of serum Cu were included in meta-analysis. HT patients had lower serum Zn [SMD (95%CI): -0.612(-0.951, -0.274), z = 3.54, P_{for z} <0.001; I² = 97.0%, P_forI² <0.001], whereas no significant difference of serum Cu was shown between HT patients and controls [SMD (95%CI): 0.153(-0.101, 0.407)]. Also, male HT patients had lower serum Zn [SMD (95%CI): -1.443(-2.868, -0.017), z = 1.98, P_{for z} = 0.047; I² = 98.8%, P_forI² <0.001]. In subgroup analysis, a lower serum Zn was observed in HT patients in studies conducted in Europe [-1.066(-1.759, -0.374)], in case-control studies [-0.718(-1.294, -0.142)], in matched case-control studies [-0.939(-1.646, -0.233)] and studies involving treated patients [-1.416(-2.195, -0.638)]. Meanwhile, a higher serum Cu was found in HT patients in studies conducted in Africa [1.96(1.402, 2.518)], and in matched case-control studies [0.655(0.204, 1.107)].

CONCLUSION

The present meta-analysis indicates that serum Zn level in HT patients was significantly lower than that in controls, while no significantly different serum Cu level was found between HT patients and controls. Future studies are needed to confirm these results in future research.

Associations Between Copper and Zinc and Risk of Hypertension in US Adults

Evidence linking copper and zinc to hypertension are limited and conflicting. Data from the National Health and Nutrition Examination Survey (NHANES) 2007-2014 were used. Zinc and copper intake from diet and supplements was assessed with 24-h dietary recall. Hypertension was defined as systolic blood pressure (SBP) ≥ 140 mmHg/diastolic blood pressure (DBP) ≥ 90 mmHg/treatment with hypertensive medications. In a sensitivity analysis, according to the 2017 American College of Cardiology and American Heart Association guideline, hypertension was also defined as SBP ≥ 130 mmHg/DBP ≥ 80 mmHg/treatment with hypertensive medications. A total of 17,811 adults (8430 men and 9381 women) were included. After adjustment for age, gender, body mass index (BMI), race, educational level, smoking status, family income, and total daily energy intake, the OR of hypertension for highest vs. lowest quartile intake of copper, zinc, and copper/zinc ratio was 1.11 (0.90-1.37), 1.11 (0.90-1.35), and 0.95 (0.81-1.11), respectively. In stratified analysis by BMI (< 25 kg/m², 25-30 kg/m², > 30 kg/m²), no significant association was found between hypertension and intakes of copper, zinc, and copper/zinc ratio (highest vs. lowest quartile) in multivariate analysis. In multivariate analysis, the OR of hypertension for highest vs. lowest quartile levels of serum copper, zinc, and copper/zinc ratio was 1.11 (0.61-2.04), 1.43 (0.84-2.44), and 0.68 (0.34-1.33), respectively. Similar results were found in the sensitivity analysis. Zinc and copper might be not independently associated with hypertension in US adults.

Plasma and saliva levels of three metals in waterpipe smokers: a case control study

In this case-control study, the influence of waterpipe tobacco smoking on the plasma and saliva levels of cadmium, lead and zinc was examined in participants who were waterpipe tobacco smokers (WS) or never-smokers (NS). The concentration of metals was higher in WS relative to NS. The mean (SEM) cadmium concentration in plasma was 3.3 (0.18) µg/dL in WS versus 0.82 (0.09) µg/L in NS (p < .001) and in saliva was 5.1 (0.36) µg/L in WS versus 0.64 (0.2) µg/L in NS (p < .001). The mean (SEM) lead concentration in plasma was 5.2 (0.25) µg/dL in WS versus 3.4 (0.41) µg/dL in NS (p < .01) and in saliva was 4.8 (0.58) µg/L in WS versus 2.8 (0.27) µg/L in NS (p < .05). Similarly, a significant difference in zinc concentration was observed, with a mean of 2.0 (0.17) µg/mL in WS plasma versus 1.49 (0.16) µg/mL in NS (p < .05) and a mean 0.94 (0.07) µg/mL in WS saliva versus 0.45 (0.06) µg/mL in NS (p < .01). In conclusion, waterpipe tobacco smoking is associated with elevated levels of metals in body fluids. These results provide another demonstration of how waterpipe tobacco smoking exposes smokers to harmful toxicants.

Blood zinc levels in nursing women from different regions of the West Bank of Palestine

Pregnant and nursing women are at higher risk of zinc deficiency which can have detrimental consequences on health. We assessed blood zinc levels in 72 nursing women from the West Bank of Palestine and investigated the association between sociodemographic variables and blood zinc levels. Blood samples were analyzed for their zinc contents using graphite furnace atomic absorption spectrophotometry. Blood and data collection were performed between July and December 2016. The median blood zinc level was 4.53 mg/L (interquartile range of 0.38 mg/L). In unadjusted analyses, blood zinc levels were higher in nursing women who lived in cities (p-value <.001), had higher household income (p-value <.001), whose husbands had a white collar job (p-value <.05), were nonsmokers (p-value <.05), did not use hair dyes (p-value <.05), and consumed energy beverages (p-value <.001). Multiple linear analysis showed that living in cities and consuming energy beverages remained significantly associated with higher blood zinc levels (p-value <.05). Blood zinc levels were in the range previously reported for similar non-malnourished populations. Nursing women living in cities and those consuming energy beverages tended to have higher blood zinc levels. Urbanized lifestyle might have enhanced blood zinc levels in nursing women.

The impact of tetrahydrobiopterin administration on endothelial function before and after smoking cessation in chronic smokers

Cardiovascular disease mortality is reduced following smoking cessation but the reversibility of specific atherogenic risk factors such as endothelial dysfunction is less established. We assessed brachial artery flow-mediated dilation (FMD) in 57 chronic smokers and 15 healthy controls, alone and after oral tetrahydrobiopterin (BH4) administration, to assess the extent to which reduced bioactivity of BH4, a cofactor for the endothelial nitric oxide synthase enzyme (eNOS), contributes to smoking-associated reductions in FMD. Thirty-four smokers then ceased cigarette and nicotine use for 1 week, after which FMD (±BH4 administration) was repeated. Brachial artery FMD was calculated as the peak dilatory response observed relative to baseline (%FMD). Endothelium-independent dilation was assessed by measuring the dilatory response to sublingual nitroglycerin (%NTG). Chronic smokers exhibited reduced %FMD relative to controls: (5.6±3.0% vs. 8.1±3.7%; P<0.01) and %NTG was not different between groups (P=0.22). BH4 administration improved FMD in both groups (P=0.03) independent of smoking status (P=0.78) such that FMD was still lower in smokers relative to controls (6.6±3.3% vs. 9.8±3.2%; P<0.01). With smoking cessation, FMD increased significantly (from 5.0±2.9 to 7.8±3.2%;P<0.01); %NTG was not different (P=0.57) and BH4 administration did not further improve FMD (P=0.33). These findings suggest that the blunted FMD observed in chronic smokers, likely due at least in part to reduced BH4 bioactivity and eNOS uncoupling, can be restored with smoking cessation. Post-cessation BH4 administration does not further improve endothelial function in chronic smokers, unlike the effect observed in nonsmokers, indicating a longer-term impact of chronic smoking on vascular function that is not acutely reversible.

Correlation of zinc with oxidative stress biomarkers

Hypertension and smoking are related with oxidative stress (OS), which in turn reports on cellular aging. Zinc is an essential element involved in an individual's physiology. The aim of this study was to evaluate the relation of zinc levels in serum and urine with OS and cellular aging and its effect on the development of hypertension. In a Spanish sample with 1500 individuals, subjects aged 20-59 years were selected, whose zinc intake levels fell within the recommended limits. These individuals were classified according to their smoking habits and hypertensive condition. A positive correlation was found (Pearson's C=0.639; p=0.01) between Zn serum/urine quotient and oxidized glutathione levels (GSSG). Finally, risk of hypertension significantly increased when the GSSG levels exceeded the 75 percentile; OR=2.80 (95%CI=1.09-7.18) and AOR=3.06 (95%CI=0.96-9.71). Low zinc levels in serum were related with OS and cellular aging and were, in turn, to be a risk factor for hypertension.

Hypertension and the fat-soluble vitamins A, D and E

Hypertension affects populations globally and is thus a public health and socio-economic problem. Macronutrient and micronutrient deficiencies are common in the general population, and may be even more prevalent in hypertensive patients. This study aimed to determine a possible association between hypertension and intake of fat-soluble vitamins A, D and E. Participants were from the cross-sectional Hortega nutrition study conducted with a random sample of 1514 people (50.3% women, 49.7% men) and two groups: nonhypertensive controls ≥40 years old (n = 429; 28.3%); unknown untreated hypertension cases ≥40 years old (n = 246; 16.2%). Biochemical and anthropometric measurements were taken. Data on dietary intakes, education, socio-economic status, place of residence, health habits, comorbidities, alcohol consumption and smoking were collected and assessed. A descriptive data study was done and compared by ANOVA and Chi-Square. No p value higher than 0.05 was considered significant. The results showed that vitamin A intake was higher in the hypertensive subpopulation (1732.77 ± 962.27 µg vs. 1655.89 ± 902.81 µg), and vitamin D and E intakes were lower (8.13 ± 9.71 µg vs. 8.25 ± 9.52 µg and 18.79 ± 7.84 mg vs. 18.60 ± 8.20 mg, respectively). No statistically significant differences were found in any adjusted model. This study did not significantly associate intake of vitamins A, D and E with hypertension in people aged over 40. Future studies on this topic and a larger sample are necessary.