Marginal copper deficiency and atherosclerosis

Linking Metallic Micronutrients and Toxic Xenobiotics to Atherosclerosis and Fatty Liver Disease-Postmortem ICP-MS Analysis of Selected Human Tissues

Dyslipidaemia is a disorder of the lipid metabolism, caused mainly by poor eating habits. The most severe consequence of an inappropriate diet is the development of atherosclerosis and hepatic steatosis. It is generally believed that a change in nutrition, and increased physical activity can eliminate these health problems. The contemporary research and therapies used to treat dyslipidemia mainly focus on lowering the triglyceride and cholesterol levels. However, disturbances in trace element homeostasis or the accumulation of toxic elements can also affect physiological processes, and be involved in the development of metabolically mediated diseases. The present study aimed to determine the mineral profiles of liver and brain tissues collected at autopsy (n = 39) in groups of people with hepatic steatosis (n = 5), atherosclerosis (n = 9), hepatic steatosis, and atherosclerosis (n = 16), and others without the selected disorders (n = 9). Concentrations of 51 elements were analysed via inductively coupled plasma mass spectrometry (ICP-MS) after the initial wet mineralisation of the samples with nitric acid. The results obtained allow us to conclude that the hepatic steatosis group suffers from a deficiency of important trace elements, such as copper, zinc, and molybdenum (p < 0.05), whereas the group with atherosclerosis is characterised by elevated levels of cadmium in the liver tissue (p = 0.01). Analysing the mean values of the element concentrations measured in 11 brain areas, statistically significant higher levels of calcium and copper (p < 0.001) were found in the atherosclerosis group, compared to the hepatic steatosis group, confirming the involvement of these elements in the pathogenesis of atherosclerosis. In addition, an accumulation of cadmium, lead, titanium, and strontium in the brain tissue was observed in the atherosclerosis group. While the accumulation of individual elements differs in different parts of the brain, the differences in the cadmium content (p < 0.05) between the study groups apply to the whole brain, except for the nucleus accumbens septi area, where a statistically significant titanium accumulation occurs in the atherosclerosis and steatosis groups, compared to the others (p < 0.05). In addition, the disruption of elemental homeostasis in the brain of a single case with bipolar disorder, and a case with hip replacement was observed. Our results confirm the involvement of chemical elements in the pathogenesis of selected metabolic diseases, and the need for further studies in larger populations.

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.

Serum copper, ceruloplasmin, and their relations to metabolic factors in nonalcoholic fatty liver disease: a cross-sectional study

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) characterized by excessive intrahepatic fat accumulation is increasing worldwide. This study aimed to investigate serum copper (Cu) and ceruloplasmin (Cer) levels and their relations to metabolic factors in NAFLD.

METHODS

This cross-sectional study was conducted on 141 subjects with NAFLD diagnosed using abdominal ultrasonography. Personal information, anthropometric measures, glucose and lipid profile, and serum levels of liver enzymes were assessed. Fasting serum levels of Cu and Cer were determined using colorimetry and nephelometry assay, respectively. Odds ratios (ORs) were used to examine the associations of serum Cu and Cer levels with NAFLD risk.

RESULTS

The results on 85 patients with NAFLD and 56 apparently healthy participants showed that all NAFLD cases and 53.6% of the healthy subjects were overweight or obese. More than half of the patients (58.8%) showed mild NAFLD. Age, weight, BMI, lipid profile, uric acid, and ferritin were significantly higher in NAFLD patients than the healthy cases. No significant differences were found in the concentrations of Cu and Cer between the groups. Only 7.4% of the healthy subjects and 2.4% of the patients were Cu deficient (<70 µg/dl). No association was found between the risk of NAFLD and serum Cu [OR: 0.994; 95% confidence interval (CI): 0.981-1.006] and Cer levels (OR: 0.414; 95% CI: 0.001-123.604) after adjusting for the confounders.

CONCLUSION

Our findings revealed no association between Cu deficiency and NAFLD risk. Further human studies with larger sample sizes are required to investigate how Cu and Cer status may affect NAFLD.

Dietary Cholesterol Supplements Disturb Copper Homeostasis in Multiple Organs in Rabbits: Aorta Copper Concentrations Negatively Correlate with the Severity of Atherosclerotic Lesions

Dietary cholesterol causes atherosclerosis along with a reduction of copper concentrations in the atherosclerosis wall. This study was to determine the relationship between aorta copper concentrations and the severity of atherosclerotic lesions as well as copper homeostasis in multiple organs in cholesterol-fed rabbits. Male New Zealand white rabbits, 10-week-old and averaged 2.0 kg, were fed a diet containing 1% (w/w) cholesterol or the same diet without cholesterol as controls. Twelve weeks after the feeding, aortic atherosclerotic lesions, serum cholesterol, and multiple organ copper concentrations were measured. Compared to controls, rabbits fed cholesterol-supplemented diet displayed higher serum cholesterol levels and developed atherosclerosis. Copper concentrations in the cholesterol-fed rabbits were increased in the serum and kidney but decreased in the atherosclerosis wall and multiple organs, including heart, liver, spleen, and lung. Furthermore, aorta copper concentrations negatively correlated, respectively, with the severity of the atherosclerotic lesion (r = - 0.64, p = 0.01), the microscope atherosclerotic lesion area (r = - 0.60, p = 0.02), and the stenosis of the lumen (r = - 0.54, p = 0.04). Dietary cholesterol not only causes atherosclerosis but also disturbs copper homeostasis in multiple organ systems. The negative correlation between aorta copper concentrations and the severity of atherosclerotic lesions suggests a vicious cycle between copper reduction and the pathogenesis of atherosclerosis. These changes in copper homeostasis would be additive to atherosclerosis as a risk factor for cardiovascular disease in humans.

Atherosclerotic lesion-specific copper delivery suppresses atherosclerosis in high-cholesterol-fed rabbits

Dietary cholesterol supplements cause hypercholesterolemia and atherosclerosis along with a reduction of copper concentrations in the atherosclerotic wall in animal models. This study was to determine if target-specific copper delivery to the copper-deficient atherosclerotic wall can block the pathogenesis of atherosclerosis. Male New Zealand white rabbits, 10-weeks-old and averaged 2.0 kg, were fed a diet containing 1% (w/w) cholesterol or the same diet without cholesterol as control. Twelve weeks after the feeding, the animals were injected with copper-albumin microbubbles and subjected to ultrasound sonication specifically directed at the atherosclerotic lesions (Cu-MB-US) for target-specific copper delivery, twice a week for four weeks. This regiment was repeated 3 times with a gap of two weeks in between. Two weeks after the last treatment, the animals were harvested for analyses of serum and aortic pathological changes. Compared to controls, rabbits fed cholesterol-rich diet developed atherosclerotic lesion with a reduction in copper concentrations in the lesion tissue. Cu-MB-US treatment significantly increased copper concentrations in the lesion, and reduced the size of the lesion. Furthermore, copper repletion reduced the number of apoptotic cells as well as the content of cholesterol and phospholipids in the atherosclerotic lesion without a disturbance of the stability of the lesion. The results thus demonstrate that target-specific copper supplementation suppresses the progression of atherosclerosis at least in part through preventing endothelial cell death, thus reducing lipid infiltration in the atherosclerotic lesion.

The Study of the Aorta Metallomics in the Context of Atherosclerosis

Atherosclerosis is a multifactorial disease, for which the etiology is so complex that we are currently unable to prevent it and effectively lower the statistics on mortality from cardiovascular diseases. Parallel to modern analyses in molecular biology and biochemistry, we want to carry out analyses at the level of micro- and macroelements in order to discover the interdependencies between elements during atherogenesis. In this work, we used the Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) to determine the content of calcium, magnesium, iron, copper, chromium, zinc, manganese, cadmium, lead, and zinc in the aorta sections of people who died a sudden death. We also estimated the content of metalloenzymes MMP-9, NOS-3, and SOD-2 using the immunohistochemical method. It was observed that with the age of the patient, the calcium content of the artery increased, while the content of copper and iron decreased. Very high correlations (correlation coefficient above 0.8) were observed for pairs of parameters in women: Mn–Ca, Fe–Cu, and Ca–Cd, and in men: Mn–Zn. The degree of atherosclerosis negatively correlated with magnesium and with cadmium. Chromium inhibited absorption of essential trace elements such as Cu and Fe due to its content being above the quantification threshold only if Cu and Fe were lower. Moreover, we discussed how to design research for the future in order to learn more about the pathomechanism of atherosclerosis and the effect of taking dietary supplements on the prevalence of cardiovascular diseases.

Copper Preserves Vasculature Structure and Function by Protecting Endothelial Cells from Apoptosis in Ischemic Myocardium

The present study was undertaken to investigate whether Cu protects vasculatures from ischemic injury in the heart. C57/B6 mice were introduced to myocardial ischemia (MI) by permanent ligation of the left anterior descending (LAD) coronary artery. Two hours post-LAD ligation, mice were intravenously injected with a Cu-albumin (Cu-alb) solution, or saline as control. At 1, 4, or 7 days post-MI, hearts were collected for further analysis. A dramatic decrease in CD31-positive endothelial cells concomitantly with abundant apoptosis, along with obstruction of blood flow, was observed in ischemic myocardium 1 day post-MI. The early Cu-alb treatment protected CD31-positive cells from apoptosis, along with a preservation of micro-vessels and a decrease in infarct size. This early vasculature preservation ensured myocardial blood perfusion and protected cardiac contractile function until 28 days post-MI. This strategy of Cu-alb treatment immediately following MI would help develop a therapeutic approach for acute heart attack patients in a clinical setting.

Trace element, immune and opioid biomarkers of unstable angina, increased atherogenicity and insulin resistance: Results of machine learning

BACKGROUND

Aberrations in endothelial cells, immune and oxidative pathways are associated with atherosclerosis (ATS) and unstable angina (UA). The role of trace elements, minerals, and the endogenous opioid system (EOS) in UA are less well established.

METHODS

We measured lipid, insulin resistance (IR), and immune, trace element (copper and zinc), mineral (magnesium, calcium), EOS (β-endorphin and mu-opioid receptor (MOR)) and antioxidant (vitamin D3) biomarkers in patients with ATS (n = 60) and UA (n = 60) and healthy controls (n = 58).

RESULTS

ATS patients showed increased atherogenic and IR indices, IL-6, IL-10, β-endorphin, copper and magnesium, and lower zinc than healthy controls. Logistic regression showed that UA was significantly discriminated from ATS without UA with an accuracy of 85.5 % using calcium, IL-10, β-endorphin, MOR, triglycerides, IR (all positively), and copper and vitamin D3 (inversely). Neural networks showed that UA was discriminated from ATS without UA with an area under the ROC curve of 0.942 using MOR, β-endorphin, calcium, insulin resistance, vitamin D3 and copper as input variables. We found that 50.0 % of the variance in IR was explained by the regression on copper, IL-10, IL-6 (all positively), and zinc (inversely), while 32.9 % of the variance in the atherogenic index of plasma was explained by copper, IL-10 (both positively), and magnesium (inversely).

CONCLUSION

UA is not only mediated by insulin resistance, atherogenicity, and immune disorders, but also by aberrations in the endogenous opioid system and trace elements as well as lowered antioxidant levels. Copper appears to play a key role in IR and atherogenicity.

DISTINCT PHENOTYPE OF NON-ALCOHOLIC FATTY LIVER DISEASE IN PATIENTS WITH LOW LEVELS OF FREE COPPER AND OF CERULOPLASMIN

BACKGROUND

Copper deficiency has been linked to alterations in lipid metabolism and hepatic steatosis. Oxidative stress plays a role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). One of the enzymes that neutralize oxidative stress is Cu/Zn superoxide dismutase, which depends on the availability of adequate amounts of copper.

OBJECTIVE

Correlate the levels of ceruloplasmin and of non-ceruloplasmin-bound copper (NCBC) with clinical, biochemical and histological parameters of non-alcoholic fatty liver disease (NAFLD) patients.

METHODS

Data from 95 consecutively admitted NAFLD patients who underwent liver biopsy composed the groups based on ceruloplasmin levels lower than 25 mg/dL and on negative NCBC. The risk factors for NAFLD in each group were compared.

RESULTS

Body mass index was lower in patients with ceruloplasmin <25 mg/dL (29.1±3.47 vs 32.8±6.24 kg/m2; P=0.005) as were the levels of LDL, HDL and total cholesterol, when compared with their counterparts with ceruloplasmin >25 mg/dL (101±38 vs 116±35 mg/dL, P=0.05; 43±9 vs 51±16 mg/dL, P=0.01; 174±43 vs 197±39 mg/dL, P=0.01, respectively). Mean serum ferritin levels were higher in the ceruloplasmin <25 mg/dL group (343±327 vs 197±190 ng/mL; P=0.02). Otherwise, patients with negative NCBC had higher HOMA-IR (8.2±14.7 vs 4.6±3.7; P=0.03). Age, gender, hypertension and diabetes showed no statistical difference.

CONCLUSION

Patients with NAFLD had different clinical and biochemical markers according to the levels of NCBC and ceruloplasmin.

Dataset of the analyzing trace elements and minerals via ICP-MS: Method validation for the mammalian tissue and serum samples

Minerals and trace elements play vital role in the biological functions for all organisms including human and other mammals. Therefore, imbalance in the mineral and/or trace element levels may cause formation of several diseases including cancer, diabetes, cardiovascular diseases, and neurological disorders. ICP-MS (inductively coupled plasma - mass spectrometry) is described as the most sensitive and accurate method. Here we reported an effective and fast protocol as method validation to evaluate trace element and minerals via ICP-MS in the mammalian tissue and serum samples. Our data showed that minimum relative standard deviation (RSD) values with the ICP-MS were observed when we used microwave digestion with the SUPRAPUR® grade nitric acid at the lower dilution rates. Our protocol validation may help researchers to measure trace elements and minerals in the mammalian samples fast, easily and accurately. EMSURE® grade HNO3 caused cross contamination in the serum and tissue samples. Our protocol validation may help researchers to measure trace elements and minerals in the mammalian samples fast, easily and accurately.

Physiological role of Prion Protein in Copper homeostasis and angiogenic mechanisms of endothelial cells

The Prion Protein (PrP) is mostly known for its role in prion diseases, where its misfolding and aggregation can cause fatal neurodegenerative conditions such as the bovine spongiform encephalopathy and human Creutzfeldt–Jakob disease. Physiologically, PrP is involved in several processes including adhesion, proliferation, differentiation and angiogenesis, but the molecular mechanisms behind its role remain unclear. PrP, due to its well-described structure, is known to be able to regulate copper homeostasis; however, copper dyshomeostasis can lead to developmental defects. We investigated PrP-dependent regulation of copper homeostasis in human endothelial cells (HUVEC) using an RNA-interference protocol. PrP knockdown did not influence cell viability in silenced HUVEC (PrPKD) compared to control cells, but significantly increased PrPKD HUVEC cells sensitivity to cytotoxic copper concentrations. A reduction of PrPKD cells reductase activity and copper ions transport capacity was observed. Furthermore, PrPKD-derived spheroids exhibited altered morphogenesis and their derived cells showed a decreased vitality 24 and 48 hours after seeding. PrPKD spheroid-derived cells also showed disrupted tubulogenesis in terms of decreased coverage area, tubule length and total nodes number on matrigel, preserving unaltered VEGF receptors expression levels. Our results highlight PrP physiological role in cellular copper homeostasis and in the angiogenesis of endothelial cells.

Prediction of carotid intima-media thickness in obese patients with low prevalence of comorbidities by serum copper bioavailability

BACKGROUND AND AIM

Western societies, with growing prevalence, suffer from various metabolic diseases like obesity and hepatic steatosis, better defined as non-alcoholic fatty liver disease, or cardiovascular (CV) diseases that are strictly linked to each other. The association of their occurrence with the altered homeostasis of metals is an intriguing issue. Copper in particular was identified as key player in various metabolic derangements. On these bases, we aimed at investigating the possible association of serum copper levels with an indicator of early CV risk as the intima-media thickness (IMT) of carotid artery and its predictive value in a selected population of obese patients.

METHODS

We performed a cross-sectional study recruiting 100 obese patients characterized by a low prevalence of comorbidities. Ultrasound investigation for hepatic steatosis and IMT evaluation were performed. Serum samples were collected and then analyzed through atomic absorption spectrometry to evaluate their copper content. Possible correlations between copper bioavailability and biochemical, clinical, and anthropometric characteristics of patients were sought.

RESULTS

Age negatively predicted copper serum levels of patients (P = 0.009). However, the most interesting finding is the negative prediction of IMT by the copper serum levels (t = -2.23, P = 0.028, least absolute deviations regression). Factor analysis confirmed the aforementioned inverse correlation and highlighted the strong inverse correlation between smoking and copper serum levels.

CONCLUSION

Our data show that an altered copper bioavailability predicts early atherosclerosis as main CV risk in obese patients with hepatic steatosis detected by ultrasound, shedding some light in this pathological scenario.

Health hazards of child labor in the leather products and surgical instrument manufacturing industries of Sialkot, Pakistan

Child labor is a major challenge in the developing countries and comprehensive health hazard identification studies on this issue are still lacking. Therefore, the current study is an effort to highlight the health concerns of child labor exposed in the key small scale industries of Sialkot, Pakistan. Our findings revealed jolting levels of heavy metals in the urine, blood, serum, saliva, and hair samples collected from the exposed children. For example, in the urine samples, Cd, Cr, Ni, and Pb were measured at the respective concentrations of 39.17, 62.02, 11.94 and 10.53 μg/L in the surgical industries, and 2.10, 4.41, 1.04 and 5.35 μg/L in the leather industries. In addition, source apportionment revealed polishing, cutting, and welding sections in the surgical industries and surface coating, crusting, and stitching sections in the leather industries were the highest contributors of heavy metals in the bio-matrices of the exposed children, implying the dusty, unhygienic, and unhealthy indoor working conditions. Further, among all the bio-matrices, the hair samples expressed the highest bioaccumulation factor for heavy metals. In accordance with the heavy metal levels reported in the exposed children, higher oxidative stress was found in the children working in the surgical industries than those from the leather industries. Moreover, among heavy metals' exposure pathways, inhalation of industrial dust was identified as the primary route of exposure followed by the ingestion and dermal contact. Consequently, chemical daily intake (CDI), carcinogenic and non-carcinogenic hazard quotients (HQs) of heavy metals were also reported higher in the exposed children and were also alarmingly higher than the corresponding US EPA threshold limits. Taken all together, children were facing serious health implications in these industries and need immediate protective measures to remediate the current situation.

Neointima Formation in the Rat Carotid Artery is Exacerbated by Dietary Copper Deficiency

Dietary copper is an essential trace element with roles in both functional and structural aspects of the cardiovascular system. In particular, the vascular response to inflammatory stimuli is known to be significantly augmented in copper-deficient rats. The current study was designed to quantify the extent of injury-induced neointimal proliferation and stenosis in rats fed diets either adequate or deficient in copper. Male, weanling Sprague-Dawley rats were fed purified diets that were either adequate (CuA; 5.6 μg Cu/g) or deficient (CuD; 0.3 μg Cu/g) in copper for 4 weeks. Balloon injury was induced in the left external carotid arteries. Fourteen days after injury, histomorphometric analysis of cross-sections from carotid arteries showed increased neointimal formation in the CuD group compared with the CuA controls (neointima/media ratio: 4.55 ± 0.93 vs 1.45 ± 0.2, respectively). These results correspond with data indicating that the activity of Cu/Zn-superoxide dismutase (SOD) is depressed in rats fed this CuD diet. Because superoxide anion and redox status are known to play a key role in the extent of neointimal formation in response to injury, we propose that the exaggerated neointimal proliferation seen in the CuD group is the result of the diminished Cu/Zn-SOD activity.

Hair elements and healthy aging: a cross-sectional study in Hainan Island, China

Healthy aging is considered as the core issue of aging population. Centenarians are a symbol of healthy aging. Concentration of elements in hair is an indicator of micronutrient status, which can affect the human health. In the present study, we investigated element concentrations in the scalp hair of 255 healthy centenarians from Hainan Island, China. The pattern of intergenerational transmission of elements and the effects of confounders such as sex, age, education level, smoking habits, alcohol intake, and frequency of hospitalization on hair element concentrations were assessed. For most elements, the load in hair increased significantly through intergenerational transmission (i.e., centenarians < children < grandchildren). Our results also demonstrated that female centenarians had significantly higher concentrations of Ca, Mg, Mn, Se, and Sr but lower levels of Cr and P. The Mn level was statistically significantly lower in the primary studies group. Alcohol intake was positively associated with Cd and Na levels, whereas smoking habits showed no significant effect on all the elements. Furthermore, the frequency of hospitalization was significantly positively associated with Cd, Cu, and Pb concentration. Moreover, our analysis suggested that adequate concentrations of Fe and Se might increase the life span of centenarians, whereas excessive concentrations of P and Pb were harmful to health and reduced life span. These results imply that element concentrations could be manipulated as a therapeutic modality in geriatric disease. They might also provide reference values for diseased subjects, allowing improved diagnoses and more effective therapies, which might support effective policies on health and aging.

Association between Longevity and Element Levels in Food and Drinking Water of Typical Chinese Longevity Area

OBJECTIVES

To carrying out an integrated analysis on regional environment and human health in China and to detect the association between longevity and daily element intake from food and drinking water.

DESIGN

Cross-sectional study.

SETTING

All the 18 cities and counties in Hainan Province.

MEASUREMENTS

The distribution of elderly population and longevity indexes at a county level in Hainan Province were investigated. Quality of food and drinking water in Hainan was evaluated by comparing the chemical elements with National Standards. In addition, the association between element concentrations in food and water and longevity was examined using spearman's rank correlation.

RESULTS

The proportion of elderly people is higher in the northern part of the province compared with southern counties. Food contributes a greater proportion of daily element intake than drinking water. Compared with the National Standards, reaching rates for elements were over 85% for both food and drinking water. There was a positive correlation between daily intake of Cu, Se, and Zn from food and water and aging and longevity indexes, and a negative correlation between Pb intake and these indexes.

CONCLUSION

The quality of food and water in Hainan Province are good and that, compared with water, food is a more important source of trace elements. An appropriate supply of Cu, Se, and Zn is important, whereas excessive intake of Pb should be avoided. The findings also provide basic data to support further studies on regional variations in longevity and their relationship to diet and drinking water.

Trace elements in the wall of abdominal aortic aneurysms with and without coexisting iliac artery aneurysms

Iliac artery aneurysms (IAA) and abdominal aortic aneurysms (AAA) frequently coexist. It remains unknown whether the content of trace elements in AAA walls depends on the coexistence of IAAs. The aim of this study was to compare the content of selected trace elements in AAA walls depending on the coexistence of IAAs. The content of trace elements was assessed in samples of AAA walls harvested intraoperatively in 19 consecutive patients. In the studied group, coexisting IAAs were diagnosed in 11 out of the 19 patients with AAA. The coexistence of IAAs was associated with a slightly lower content of nickel (0.28 (0.15-0.40) vs. 0.32 (0-0.85) mg/g; p = 0.09) and a significantly higher content of cadmium (0.71 (0.26-1.17) vs. 0.25 (0.20-0.31) mg/g; p = 0.04) in AAA walls. The levels of the remaining studied elements, copper, zinc, manganese, magnesium and calcium, were comparable. The elevated levels of cadmium in the walls of AAA coexisting with IAAs may suggest an impact of the accumulation of this trace element on the greater damage of the iliac artery wall.

PM10 size distribution of metals and environmental-sanitary risk analysis in the city of Torino

The mechanisms responsible for negative biological effects due to airborne particulate matter (PM) exposure are still being studied, however the interactions between metals and biologic systems seem to be of primary importance. The aim of the study was to estimate a healthy risk linked to exposure to airborne PM10 metals by means of an environmental-sanitary risk assessment. Metals PM10 size distribution analysis was carried out in a central site of Torino city - Italy, then the Target Hazard Quotient (THQ) and the Cancer Risk (CR) were applied, according to standard EPA methods. All sampled metals were present on the different PM10 fractions, however some metals were distributed in some specific fractions: ANOVA test shows Cr, Cu, Mo and Pb as differently distributed among the eight fractions, rising the hypothesis of potential effects in specific tracts of respiratory system. Regarding the risk assessment, in general the CR was higher for an adult than for a child, conversely the THQ resulted higher for a child. While the concentrations of all the sampled metals appeared to be under control, their presence in the different PM10 fractions and their THQ and CR provided indications related to the body districts potentially in contact with these substances.

Trace elements in fingernails of healthy Chinese centenarians

Trace element concentrations in body tissues of healthy centenarians have not been widely analyzed, yet they can be used as reference data leading to improved assessment of the aging process and monitoring of the micronutrient status of this age group. The present study sought to assess trace element concentrations and behaviors in the fingernails of healthy Chinese centenarians. The effects of gender on element concentrations, which also play an important role in determining the lifespan, were also investigated. Trace elements (Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Se, Sr, and Zn) in the fingernails of 78 healthy Chinese centenarians were determined by inductively coupled plasma mass spectrometry. The overall reference values obtained in milligram per kilogram are as follows: Ba, 5.10; Cd, 0.031; Co, 0.101; Cr, 0.82; Cu, 3.71; Fe, 154.35; Li, 0.31; Mn, 3.09; Mo, 0.040; Ni, 0.95; Pb, 1.86; Se, 0.44; Sr, 6.20; and Zn, 147.96. Data analysis showed that only Cr and Se concentrations show a normal distribution, and no significant difference between male and female groups was found for any element except Cr. Result also revealed that sufficient Se, Co, and Zn as well as lower or lack of exposure to Cr contribute positively to the lifespan of centenarians. The results suggest that regulating in vivo contents of trace elements, especially Se, Co, and Zn, is reasonable to intervene with geriatric diseases.

Trace element concentrations in hair of healthy Chinese centenarians

Trace element concentrations, as indicators of micronutrient status of healthy centenarians, have not been widely analyzed. This study aimed to assess trace element concentrations in the hair of healthy centenarians. The effects of gender and age on element concentrations were also investigated. Eleven trace elements (Al, Ba, Cd, Cr, Cu, Fe, Mo, Pb, Se, Sr and Zn) in the scalp hair of 107 healthy Chinese centenarians were examined. The overall reference values (RVs) in mg/kg for the hair concentrations of trace elements in centenarians were as follows: Al, 14.95; Ba, 2.68; Cd, 0.06; Cr, 0.59; Cu, 6.21); Fe, 19.37; Mo, 0.50; Pb, 4.64; Se, 0.37; Sr, 4.84; and Zn, 154.37. Data analysis found that only Cu and Zn concentrations show a normal distribution, and there is no significant difference between males and females in any element except Zn. However, the levels of Al, Cd, Cr, Fe, Mo, Pb decrease and the levels of Ba, Cu, Se, Sr, Zn increase with age in the centenarian cohort. Results also revealed that sufficient Zn and Se concentrations as well as low exposure to heavy metals pollution contribute to the longevity of centenarians. The results imply the possibility of manipulating trace element concentrations, especially Zn and Se concentrations in tissues, as a means for therapeutic modality in geriatric disease.

Normolipidemic effect of antioxidants in low cholesterol-modified poultry eggPsi on Zn-induced dyslipidemia and liver pathology in Wistar rats

A low cholesterol (CH)-modified poultry egg (ME Psi) containing more vitamin E, lenolenic acid, and minerals Cu and Mg but low total lipid (TL) and Zn contents than the conventional egg evaluated to reduce the severity of dyslipidemia induced by excessive Zn in the diet. The experimental data was recorded on male rats fed on normolipidemic (NL) semi-synthetic basal diet containing 20 mg Zn/kg diet in control group I, Zn supplemented dyslipidemic diet-A (Zn-DL-A) and B (Zn-DL-B) containing 40 and 80 mg Zn/kg diet in groups II and III, and ME Psi-mixed Test diet-A (Zn-DL-A + 4 ME Psi) and Test diet-B (Zn-DL-B + 4 ME Psi) in groups IIEM and IIIEM, respectively, for 180 and 90 days. Data recorded on liver and blood lipid profiles showed reduction in the concentration of TL, CH, triglycerides, and glycogen (GG) in liver consequently leading to their rise in blood serum including rise in VLDL-c and LDL-c but fall in HDL-c in groups II and III rats that reversed after ME Psi treatment resulting in rise of their levels in the liver and fall in the blood of groups IIEM and IIIEM rats, respectively. Mineral status in the liver showed a rise in Zn but fall in Cu and Mg levels in groups II and III that was reversed after ME Psi treatment resulting in fall in Zn and rise in Cu and Mg concentration in the liver of groups IIEM and IIIEM rats. Hepatopathogical studies showed reduction in the dilatation of long citernal profile of endoplasmic reticulum and increase in GG and TL granules in the cytoplasm of hepatocytes of groups IIEM and IIIEM after ME Psi treatment than those of groups II and III rats. It was concluded that the inclusion of ME Psi would be helpful in reducing dyslipidemia by correcting the ionic imbalance generated by excessive Zn intake in rats or by drugs, even in chronic diseased conditions without aggravating risk factors for heart diseases in humans that need further studies.

A deleterious interaction between copper deficiency and sugar ingestion may be the missing link in heart disease

Copper deficiency plays a vital role in atherogenesis. To the long list of risk factors for atherosclerotic cardiovascular disease should be added the deleterious interaction between copper deficiency and carbohydrate consumption. Here we critically evaluate the role of copper in the diet and its role as a possible etiological factor in the development of cardiovascular disease. A possible mechanism for the development of heart disease due to copper deficiency is proposed. There are many known risk factors for the development of heart disease, including hyperlipidemia and hypertension; however, little emphasis has been placed on the role of copper on heart disease. Over the last couple of decades, dietary copper deficiency has been shown to cause a variety of metabolic changes, including hypercholesterolemia, hypertriglyceridemia, hypertension, and glucose intolerance. Interestingly, these changes are common in the United States population and they are known risk factors for heart disease. Further research in this field is warranted considering the profound implications to people in the United States and around the world who consume processed foods marginally deficient in copper and replete with sugar. The only nutritional condition with signs and symptoms of atherosclerotic cardiovascular disease may be copper deficiency. Improving levels of copper in the diet, by appropriate food selection or by addition of a daily multi-vitamin, is recommended.

The +838 C/G MT2A polymorphism, metals, and the inflammatory/immune response in carotid artery stenosis in elderly people

Carotid artery stenosis (CS) is a well-established risk factor for stroke. Increased proinflammatory chemokines, enhanced metallothionein (MT), and altered metal homeostasis may play roles in atherosclerosis progression and plaque destabilization. MT may sequester zinc during chronic inflammation, provoke zinc deficiency, and modulate NK cell cytotoxicity. A recent investigation of older patients with diabetes and atherosclerosis showed an association between the -209 A/G MT2A polymorphism, CS, and zinc status. In this study, we evaluated the relationship between two MT2A polymorphisms (-209 and + 838 locus), metal status, and inflammatory/immune response in older patients with CS only (the CS1 group) or with CS and previous cerebrovascular episodes (transient ischemic attack or stroke) (the CS2 group). A total of 506 individuals (188 CS1, 100 CS2, and 218 healthy controls) were studied. Atherosclerotic patients (CS1 and CS2) showed increased levels of MT, MCP-1, and RANTES, reduced NK cell cytotoxicity, and altered trace element concentrations (zinc, copper, magnesium, iron). The +838 C/G MT2A polymorphism was differently distributed in CS1 and CS2 patients, who displayed the GG genotype (C-) with significantly higher frequency than elderly controls. C- carriers showed increased MCP-1 and decreased NK cell cytotoxicity, CD56+ cells, and intracellular zinc availability along with decreased zinc, copper, and magnesium content in erythrocytes and increased iron in plasma. C- carriers also showed a major incidence of soft carotid plaques. In conclusion, the +838 C/G MT2A polymorphism seems to influence inflammatory markers, zinc availability, NK cell cytotoxicity, and trace element status, all of which may promote CS development.

How reliable and robust are current biomarkers for copper status?

Cu is an essential nutrient for man, but can be toxic if intakes are too high. In sensitive populations, marginal over- or under-exposure can have detrimental effects. Malnourished children, the elderly, and pregnant or lactating females may be susceptible for Cu deficiency. Cu status and exposure in the population can currently not be easily measured, as neither plasma Cu nor plasma cuproenzymes reflect Cu status precisely. Some blood markers (such as ceruloplasmin) indicate severe Cu depletion, but do not inversely respond to Cu excess, and are not suitable to indicate marginal states. A biomarker of Cu is needed that is sensitive to small changes in Cu status, and that responds to Cu excess as well as deficiency. Such a marker will aid in monitoring Cu status in large populations, and will help to avoid chronic health effects (for example, liver damage in chronic toxicity, osteoporosis, loss of collagen stability, or increased susceptibility to infections in deficiency). The advent of high-throughput technologies has enabled us to screen for potential biomarkers in the whole proteome of a cell, not excluding markers that have no direct link to Cu. Further, this screening allows us to search for a whole group of proteins that, in combination, reflect Cu status. The present review emphasises the need to find sensitive biomarkers for Cu, examines potential markers of Cu status already available, and discusses methods to identify a novel suite of biomarkers.

[Effects of copper supplementation on lipid profiles in elderly patients with copper deficiency]

AIM

The purpose of this study was to examine the effects of copper supplementation on lipid profiles in elderly patients with copper deficiency.

METHODS

Nine long-term bed-ridden, patients (5 men and 4 women, mean age 83.3+/-8.7 years old) with severe copper deficiency, who had a serum copper of 15 microg/dL or less (normal range 70-140 microg/dL), had their diets supplemented with copper sulfate (3 mg/day) over 12 weeks in addition to their diet of only one kind of enteral food with a low concentration of copper. Copper, ceruloplasmin, total cholesterol (TC), triacylglycerides (TG), HDL-cholesterol (HDL-C), c-reactive protein (CRP), creatinine (Cr), zinc (Zn) and albumin (Alb) in the serum were measured before, 4 weeks and 12 weeks after copper supplementation.

RESULTS

Serum copper and ceruloplasmin were significantly increased at 4 weeks after copper supplementation. TG was significantly increased at 4 weeks after copper supplementation, but at 12 weeks the increase of TG was not significant. TC, HDL-C, CRP, Cr, Zn and Alb were not changed by copper supplementation.

CONCLUSION

TG was transiently increased by copper supplementation in elderly patients with copper deficiency. TC and HDL-C were not changed by copper supplementation.

The +838 C/G MT2A polymorphism, metals, and the inflammatory/immune response in carotid artery stenosis in elderly people

Carotid artery stenosis (CS) is a well-established risk factor for stroke. Increased proinflammatory chemokines, enhanced metallothionein (MT), and altered metal homeostasis may play roles in atherosclerosis progression and plaque destabilization. MT may sequester zinc during chronic inflammation, provoke zinc deficiency, and modulate NK cell cytotoxicity. A recent investigation of older patients with diabetes and atherosclerosis showed an association between the -209 A/G MT2A polymorphism, CS, and zinc status. In this study, we evaluated the relationship between two MT2A polymorphisms (-209 and + 838 locus), metal status, and inflammatory/immune response in older patients with CS only (the CS1 group) or with CS and previous cerebrovascular episodes (transient ischemic attack or stroke) (the CS2 group). A total of 506 individuals (188 CS1, 100 CS2, and 218 healthy controls) were studied. Atherosclerotic patients (CS1 and CS2) showed increased levels of MT, MCP-1, and RANTES, reduced NK cell cytotoxicity, and altered trace element concentrations (zinc, copper, magnesium, iron). The +838 C/G MT2A polymorphism was differently distributed in CS1 and CS2 patients, who displayed the GG genotype (C-) with significantly higher frequency than elderly controls. C- carriers showed increased MCP-1 and decreased NK cell cytotoxicity, CD56+ cells, and intracellular zinc availability along with decreased zinc, copper, and magnesium content in erythrocytes and increased iron in plasma. C- carriers also showed a major incidence of soft carotid plaques. In conclusion, the +838 C/G MT2A polymorphism seems to influence inflammatory markers, zinc availability, NK cell cytotoxicity, and trace element status, all of which may promote CS development.

Copper and human health: biochemistry, genetics, and strategies for modeling dose-response relationships

Copper (Cu) and its alloys are used extensively in domestic and industrial applications. Cu is also an essential element in mammalian nutrition. Since both copper deficiency and copper excess produce adverse health effects, the dose-response curve is U-shaped, although the precise form has not yet been well characterized. Many animal and human studies were conducted on copper to provide a rich database from which data suitable for modeling the dose-response relationship for copper may be extracted. Possible dose-response modeling strategies are considered in this review, including those based on the benchmark dose and categorical regression. The usefulness of biologically based dose-response modeling techniques in understanding copper toxicity was difficult to assess at this time since the mechanisms underlying copper-induced toxicity have yet to be fully elucidated. A dose-response modeling strategy for copper toxicity was proposed associated with both deficiency and excess. This modeling strategy was applied to multiple studies of copper-induced toxicity, standardized with respect to severity of adverse health outcomes and selected on the basis of criteria reflecting the quality and relevance of individual studies. The use of a comprehensive database on copper-induced toxicity is essential for dose-response modeling since there is insufficient information in any single study to adequately characterize copper dose-response relationships. The dose-response modeling strategy envisioned here is designed to determine whether the existing toxicity data for copper excess or deficiency may be effectively utilized in defining the limits of the homeostatic range in humans and other species. By considering alternative techniques for determining a point of departure and low-dose extrapolation (including categorical regression, the benchmark dose, and identification of observed no-effect levels) this strategy will identify which techniques are most suitable for this purpose. This analysis also serves to identify areas in which additional data are needed to better define the characteristics of dose-response relationships for copper-induced toxicity in relation to excess or deficiency.

Relevance, essentiality and toxicity of trace elements in human health

The metals Mn, Fe, Cu, and Zn, and the non-metal Se are considered "trace elements" (TE) because of their essentiality and very limited quantity in humans. The biological activities of Cu, Fe, Mn, and Se are strongly associated with the presence of unpaired electrons that allow their participation in redox reactions. In biological systems these metals are mostly bound to proteins, forming metalloproteins. Many of the metals in metalloproteins are part of enzymatic systems, have structural and storage functions, or use the protein to be transported to their target site in the organism. In humans Mn, Fe, Cu, Zn, and Se accomplish decisive functions to maintain human health. Deficiency in any of these TE leads to undesirable pathological conditions that can be prevented or reversed by adequate supplementation. In sufficiently nourished persons, supplementation should be carefully controlled, given the toxic effects ascribed to TE when present in quantities exceeding those required for accomplishing their biological functions. The dietary reference intakes provided by national regulatory agencies are guides to define intake, supplementation and toxicity of Mn, Fe, Cu, Zn, and Se, as well other elements considered micronutrients for humans.

[The content of copper and zinc in human ulcerated carotid plaque]

INTRODUCTION

Copper and zinc have significant antiatherogenic effect influencing activity of antioxidant enzymes (glutathione-peroxidase and superoxide-dismutase), mechanism of apoptosis and other mechanisms. Few studies showed increased copper and zinc concentration in atherosclerotic plaque in comparison to normal vascular tissue.

AIM

The aim of the study was to compare copper and zinc concentrations in carotid artery tissue without significant atherosclerotic changes and human ulcered atherosclerotic plaque.

MATERIAL AND METHODS

Study was conducted on 66 patients. Carotid endarterectomy due to the significant carotid atherosclerotic changes with cerebrovascular disorders was performed in 54 patients (81.8%). Control group consisted of 12 patients (18.2%) without carotid atherosclerotic changes operated due to the symptomatic kinking and coiling of carotid artery. Operated group consisted of 38 men (62.96%) and 16 women (37.04%). Control group had the same number of patients: six men (50%) and six women (50%). Preoperatively, all patients were examined by vascular surgeon, neurologist and cardiologist. Duplex sonography of carotid and vertebral arteries was performed by Aloca DSD 630 ultrasound with mechanical and linear transducer 7.7 MHz. Indication for surgical treatment was obtained according to non-invasive diagnostic protocol and neurological symptoms. Copper and zinc concentration in human ulcered atherosclerotic plaque and carotid artery segment were estimated by spectrophotometry (Varian AA-5).

RESULTS

Average age of our patients was 59.8+/-8.1 years. For males average age was 76.1+/-9.8 years. And for females 42.4+/-5.8 years. In group with carotid endarterectomy female patients were significantly younger than male patients (p<0.01). In group with carotid endarterectomy clinically determined neurological disorders were found in 47 patients (87.03%)--35 male (74.47%) and 12 female patients (25.53%). Regarding risk factors for cardiovascular diseases, no significant difference among groups was found for blood pressure and smoking. However, patients with carotid endarterectomy had significantly more diabetes mellitus (p<0.05), obesity (p<0.01) and hypercholesterolemia (p<0.01).

DISCUSSION

Our study showed significantly lower total copper value in the group with human ulcered atherosclerotic plaque in comparison with the control group (p<0.05). We also found significantly lower total zinc value in the group with human ulcered atherosclerotic plaque in comparison with the control group (p<0.05).

CONCLUSION

Our study revealed significant difference in copper and zinc content between human ulcered atherosclerotic plaque and normal carotid tissue. Closer correlation of these oligoelements and endothelial dysfunction will be established in future investigations.

The effects of coadministration of dietary copper and zinc supplements on atherosclerosis, antioxidant enzymes and indices of lipid peroxidation in the cholesterol-fed rabbit

It has previously been shown that dietary copper can modulate the extent of atherosclerosis in the thoracic aorta of cholesterol-fed rabbits. The metabolism of copper and zinc are closely related, and it has been hypothesized that the balance of dietary copper to zinc may be important in determining coronary risk. Hence, we have investigated the interaction between dietary copper and zinc in atherogenesis in the New Zealand White rabbit. Juvenile male rabbits were randomly allocated to eight groups. Four groups were fed a normal chow diet with zinc (0.5%, w/w), copper (0.2%, w/w), copper plus zinc or neither in their drinking water for 12 weeks. Four other groups were fed a diet containing 0.25-1% (w/w) cholesterol plus zinc, copper, both or neither. Serum cholesterol of individual animals was maintained at approximately 20 mmol/l. Integrated plasma cholesterol levels were similar for all groups receiving cholesterol and significantly higher than those in the chow-fed groups (P < 0.001). Aortic copper concentrations were higher in the animals receiving cholesterol diets with copper compared to rabbits receiving normal chow and copper (P < 0.001). Aortic zinc content was significantly higher in cholesterol-fed rabbits supplemented with zinc alone or with copper than in those fed cholesterol alone (P < 0.001). Plasma ceruloplasmin concentrations were significantly higher in groups receiving cholesterol, irrespective of their trace element supplementation (P < 0.001). However, trace element supplementation increased the level significantly (P < 0.05). Trace element supplements did not appear to affect erythrocyte superoxide dismutase in the cholesterol-fed animals; however, zinc supplementation was associated with a significant increase in the enzyme in chow-fed animals (P < 0.05). The activity of the enzyme per mg of protein in aortic tissue was higher in animals receiving copper in the presence of cholesterol (P < 0.05) but not significantly so in its absence. Dietary trace element supplementation in cholesterol-fed animals was associated with a significant reduction in aortic lesion area. Plasma thiobarbituric acid-reactive substances and FOX concentrations were both significantly higher in the cholesterol-fed rabbits compared with the animals that fed on a chow diet (P < 0.001), and these were reduced significantly by dietary copper or zinc supplementation (P < 0.001). Hence, dietary supplements of copper or zinc at the doses used both inhibited aortic atherogenesis in the cholesterol-fed rabbits, although there was no significant additional effect when given in combination.

Role of oxidative modifications in atherosclerosis

This review focuses on the role of oxidative processes in atherosclerosis and its resultant cardiovascular events. There is now a consensus that atherosclerosis represents a state of heightened oxidative stress characterized by lipid and protein oxidation in the vascular wall. The oxidative modification hypothesis of atherosclerosis predicts that low-density lipoprotein (LDL) oxidation is an early event in atherosclerosis and that oxidized LDL contributes to atherogenesis. In support of this hypothesis, oxidized LDL can support foam cell formation in vitro, the lipid in human lesions is substantially oxidized, there is evidence for the presence of oxidized LDL in vivo, oxidized LDL has a number of potentially proatherogenic activities, and several structurally unrelated antioxidants inhibit atherosclerosis in animals. An emerging consensus also underscores the importance in vascular disease of oxidative events in addition to LDL oxidation. These include the production of reactive oxygen and nitrogen species by vascular cells, as well as oxidative modifications contributing to important clinical manifestations of coronary artery disease such as endothelial dysfunction and plaque disruption. Despite these abundant data however, fundamental problems remain with implicating oxidative modification as a (requisite) pathophysiologically important cause for atherosclerosis. These include the poor performance of antioxidant strategies in limiting either atherosclerosis or cardiovascular events from atherosclerosis, and observations in animals that suggest dissociation between atherosclerosis and lipoprotein oxidation. Indeed, it remains to be established that oxidative events are a cause rather than an injurious response to atherogenesis. In this context, inflammation needs to be considered as a primary process of atherosclerosis, and oxidative stress as a secondary event. To address this issue, we have proposed an "oxidative response to inflammation" model as a means of reconciling the response-to-injury and oxidative modification hypotheses of atherosclerosis.