Genome-wide association and Mendelian randomization study of blood copper levels and 213 deep phenotypes in humans

Metal elements are present in the human body, and their levels in the blood have important impacts on health. In this study, 2488 Chinese individuals were included in a genome-wide association study of 21 serum metal levels, with approximately 179,000 East Asian individuals in a bidirectional two-sample Mendelian randomization (MR) analysis, and 628,000 Europeans in a two-sample MR analysis. We identified two single nucleotide polymorphisms (SNPs) rs35691438 and rs671 that were significantly associated with serum copper levels (SCLs). The bidirectional two-sample MR analysis in the East Asian population showed that gamma-glutamyl transpeptidase levels have a causal effect on SCLs. SCLs have causal effects on six outcomes, namely risks of esophageal varix, glaucoma, sleep apnea syndrome, and systemic lupus erythematosus, white blood cell count, and usage of drugs affecting bone structure and mineralization. The two-sample MR analyses in the European population showed causal effects of erythrocyte copper levels on risks of carpal tunnel syndrome and compression fracture. Our results provide original insights into the causal relationship between blood metal levels and multiple human phenotypes.

A genome-wide association study in a Chinese population identifies SNPs associated with serum copper levels. Mendelian randomization analysis reveals causal effects on multiple human phenotypes in East Asian and European populations.

Copper and Copper/Zn Ratio in a Series of Children with Chronic Diseases: A Cross-Sectional Study

Copper is an essential micronutrient for humans. A cross-sectional and comparative study was done to assess serum Cu levels and serum copper/zinc (Cu/Zn) ratio and its association with nutritional indicators in a series of children and adolescents with chronic diseases. Anthropometric, biochemical, dietary, body composition, and bone densitometry assessments were carried out. Serum Cu and Zn were measured by atomic absorption spectrophotometry. Seventy-eight patients (55% women) participated. The mean serum Cu in the entire series and by nutritional status through body mass index (BMI) was normal. Serum Cu decreased significantly with age and was meaningfully higher in children than in adolescents. The risk of finding altered Cu levels in children and men was higher than in adolescents and women, respectively. Twenty-two per cent of patients had abnormal serum copper levels, 13 had hypercupremia, and four had hypocupremia. The Cu/Zn ratio was greater than 1.00 for 87% of the patients, which is an indicator of an inflammatory state. All patients with hypozincemia and hypocupremia had deficient Zn intake, but only 65% of the patients with hypercupremia had dietary Zn deficiency. Consequently, the Cu/Zn ratio could indicate an inflammatory state and a high risk of zinc deficiency in this specific child population.

Major and trace elements changes of female methamphetamine addicts during six months' compulsory treatment: Biomarkers discovery

BACKGROUND

The concentration levels of major and trace elements are significantly correlated with human health. However, studies profiling major and trace elements among female using methamphetamine are rare. This study aims to investigate the major and trace elements changes and discover elemental biomarkers in plasma of female methamphetamine (METH) addicts in six months' compulsory treatment.

METHODS

A total of 60 female METH addicts selected from drug rehabilitation center were randomly divided into three equal groups: (1) Detoxification for one month; (2) Detoxification for three months; (3) Detoxification for six months. Twenty healthy women, without drug abuse history were selected as control group. Four major elements including Na, Mg, K, Ca and twelve trace elements including V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Sn, Pb were determined using inductively coupled plasma mass spectrometry (ICP-MS). The results were analyzed using One-way Analysis of Variance (ANOVA) and Student-Newman-Keuls (SNK test). Elemental biomarkers were discovered based on orthogonal partial least squares discriminant analysis (OPLS-DA).

RESULTS

The four groups used in the study were divided into four significant sections according to scatter plots. The total elemental concentrations of three METH withdrawal groups were increased compared to the control group. Over six months, element contents of the withdrawal groups gradually equaled element contents of the control group in compulsory treatment. The variable importance in the projection values (VIP > 1) of OPLS-DA model and SNK test (p < 0.05) revealed Fe, Cu, Cr and Se as elemental biomarkers.

CONCLUSION

Major and trace elements demonstrated significant differences between control group and three METH withdrawal groups. Fe, Cu, Cr and Se are potential elemental biomarkers among METH-abused female groups. Metabolic disorders of major and trace elements exist in the female methamphetamine addicts.

Biomarkers of Zinc and Copper Status and Associated Factors in Outpatients with Ischemic and Non-Ischemic Heart Failure

Background: Few studies have explored the impact of ischemic and non-ischemic etiologies of heart failure and other factors associated with heart failure on zinc and copper status. This study examined zinc and copper status in 80 outpatients with ischemic (n = 36) and non-ischemic (n = 44) heart failure and associations with biodemographic, clinical, biochemical, and nutritional parameters.Materials: Biomarkers of plasma zinc and copper, copper-zinc ratio, 24-h urinary zinc excretion, ceruloplasmin, and dietary intake of zinc and copper were assessed. Plasma zinc and copper and urinary zinc were measured by inductively coupled plasma mass spectrometry (ICP-MS).Results: Patients with ischemic heart failure showed lower dietary zinc intake and higher dietary copper intake (both p = 0.02). Zinc and copper in plasma, copper-zinc ratio, ceruloplasmin, and 24-h urinary zinc excretion showed no statistical differences between the groups (all p ≥ 0.05). An inverse association was found between age (β =-0.001; p = 0.005) and the use of diuretics (β = -0.047; p = 0.013) and plasma zinc. Copper levels in plasma (β = 0.001; p < 0.001), and albumin (β = 0.090; p<0.001) were directly associated with plasma zinc. A positive association was found between ceruloplasmin (β = 0.011; p < 0.001), gamma-glutamyl transferase (β = 0.001; p < 0.001), albumin (β = 0.077; p = 0.001), and high-sensitivity c-reactive protein (β = 0.001; p = 0.024) and plasma copper.Conclusion: Zinc and copper biomarkers in clinically stable patients with heart failure did not seem to be responsive to the differences in zinc and copper intake observed in this study, regardless of heart failure etiology. The predictors of plasma zinc and copper levels related to oxidative stress and inflammation should be monitored in heart failure clinical practice.

Liver functions in combined models of the gentamicin induced nephrotoxicity and metabolic syndrome induced by high fat or fructose diets: a comparative study

Metabolic syndrome is one of the major risk factors that lead to various serious complications like cardiovascular abnormalities, hyperlipidemia and diabetes. Its co-incidence with other organs dysfunction results in further deterioration of the condition or precipitation of other dysfunctions. This study aimed at studying the changes in the hepatic functions after the co-incidence of the high fat or fructose diets induced metabolic syndrome along with the gentamicin induced nephrotoxicity. Briefly, six groups of male Sprague Daley rats (n = 10-12) were fed with different feeding protocols; viz; standard rodent's chow, an experimental high fat or high fructose diets feedings. For each, two groups were allocated that one of them was injected with normal saline and the other with 80 mg/kg/day I.P gentamicin during the last 24 days of the feeding period. The rats were monitored for changes in the metabolic data, glycemic control, lipid profile, renal and hepatic functions, oxidative stress and the inflammatory response. The study revealed stronger hepatic changes in the renal failure groups fed with the high fat diet rather than that in the groups fed with the high fructose diet. Although, the latter experienced a stronger deterioration in the glycemic control. The study suggests that the incidence of the hepatic changes is more linked to the incidence of the deterioration in the lipids profile that was observed after the high fat diet feeding. Overall, the co-incidence of the high fat diet induced metabolic syndrome along with the renal failure constitutes a risk factor for the hepatic dysfunction.

Associations between serum bilirubin levels and essential trace elements status in an adult population

Objective

This paper aims to evaluate the relations between serum bilirubin and essential trace elements in an adult population.

Results

Demographic and clinical data were stratified according to the median of serum bilirubin concentrations (50th percentiles). There were statistical differences in regarding with age, body mass index, white blood count, hemoglobin, mean corpuscular hemoglobin, alanine aminotransferase, creatinine, high-sensitivity C-reactive protein, iron, zinc and copper. Studying the correlation of serum bilirubin levels with iron, zinc, copper and high-sensitivity C-reactive protein, we found positive correlations for iron and zinc, and negative correlations for high-sensitivity C-reactive protein and copper in whole participants. Similar results of correlation analysis were repeated when the further analyses were performed separately for subjects with high and low serum bilirubin concentrations. Similar results were also observed in gender-based stratified analysis. Multiple linear regression analysis revealed that serum bilirubin levels were independently correlated with serum iron, zinc and copper.

Materials and Methods

The cross-sectional study involved 264 healthy subjects.

Conclusions

The current study demonstrated that serum bilirubin within the reference range is correlated with iron, zinc and copper in an adult population, regardless of potential confounders.