Elemental analysis of blood of Nigerian hypertensive subjects

Causal Effect of Genetically Determined Blood Copper Concentrations on Multiple Diseases: A Mendelian Randomization and Phenome-Wide Association Study

Exposures to copper have become a health concern. We aim to explore the broad clinical effects of blood copper concentrations. A total of 376,346 Caucasian subjects were enrolled. We performed a Mendelian randomization and phenome-wide association study (MR-PheWAS) to evaluate the causal association between copper and a wide range of outcomes in UK Biobank, and we constructed a protein-protein interaction network. We found association between blood copper concentrations and five diseases in the overall population and nine diseases in male. MR analysis implicated a causal role of blood copper in five diseases (overall population), including prostate cancer (OR = 0.87, 95% CI 0.77-0.98), malignant and unknown neoplasms of the brain and nervous system (OR = 0.58, 95% CI 0.38-0.89), and hypertension (OR = 0.94, 95% CI 0.90-0.98), essential hypertension (OR = 0.94, 95% CI 0.90-0.98) and cancer of brain and nervous system (OR = 0.63, 95% CI 0.41-0.98). For male, except for dysphagia being newly associated with blood copper (OR = 1.39, 95% CI 1.18-1.63), other MR results were consistent with the overall population. In addition, the PPI network showed possible relationship between blood copper and four outcomes, namely brain cancer, prostate cancer, hypertension, and dysphagia. Blood copper may have causal association with prostate cancer, malignant and unknown neoplasms of the brain and nervous system, hypertension, and dysphagia. Considering that copper is modifiable, exploring whether regulation of copper levels can be used to optimize health outcomes might have public health importance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43657-022-00052-3.

Cross-sectional study: Relationship between serum trace elements and hypertension

BACKGROUND

A balanced intake of trace elements is beneficial for chronic diseases such as hypertension. However, the available information regarding trace elements that may be independently associated with hypertension is limited, and the relationship between this disorder and element ratios also remains unclear.

METHODS

A total of 6,754 subjects from rural China were selected, after exclusion of patients who were under 18, had incomplete data or had additional related disorders, by multi-stage simple random and cluster sampling (participation rate: 95.22 %). Subjects were divided into a hypertensive (H) and a control (C) group. Data were collected on blood pressure and 12 serum trace elements were measured by flame atomic absorption spectrometry and inductively coupled plasma-mass spectrometry. Other basic information was collated from questionnaires and biochemical indicators were measured via kits.

RESULTS

Differences in serum levels of magnesium (Mg(mg/l): H: 27.43 ± 12.72; C: 26.33 ± 12.16), iron (Fe(mg/l): H: 1.99 ± 1.24; C: 1.84 ± 1.16), copper (Cu(mg/l): H: 1.19 ± 0.37; C: 1.10 ± 0.36), boron (B(μg/l): H: 50.00 ± 25.21; C: 47.57 ± 26.25), selenium (Se(μg/l): H: 125.12 ± 32.81; C: 118.80 ± 29.72) and chromium (Cr(μg/l): H: 8.77 ± 10.12; C: 10.12 ± 10.72) between the hypertensive and control groups were found. There were no differences in serum contents of calcium (Ca(mg/l): H: 112.43 ± 58.25; C: 111.00 ± 59.49), zinc (Zn(mg/l): H: 1.50 ± 1.97; C: 1.44 ± 1.88), arsenic (As(μg/l): H: 4.17 ± 3.94; C: 4.10 ± 4.00), manganese (Mn(μg/l): H: 4.15 ± 4.03; C: 4.07 ± 4.05), cadmium (Cd(μg/l): H: 1.14 ± 1.11; C: 1.18 ± 1.12) or lead (Pb(μg/l): H: 4.22 ± 8.90; C: 4.26 ± 10.25). The serum Cr and Cd concentrations of hypertensive men were lower than that of male controls while Mg, Cu, Ca and Se concentrations in male controls were lower. Further differences were apparent and Fe, B, Se, Mg and Cu all showed higher levels in hypertensive females whereas Cr concentrations were higher in female controls. Serum Zn and B levels showed age-related variations among hypertensive patients and concentrations of serum Cu, Zn, Se and B showed age-related variations among control subjects. For hypertensive patients, the odds ratio (OR) and 95 % confidence interval (CI) for the association of serum Cu, Se and Cr levels with hypertension were Cu: 1.36 (1.12-1.66); Se: 1.03 (1.01-1.05); Cr: 0.89 (0.83-0.96). Moreover, when the participants in the grouping with the highest copper/zinc (Cu/Zn) and magnesium/manganese (Mg/Mn) ratios were compared with the reference group, the OR and 95 % CI for hypertension were 1.22 (1.04-1.44) and 1.20 (1.01-1.42), respectively.

CONCLUSIONS

Levels of serum trace elements showed age- and sex-related differences in a group of rural Chinese adults with hypertension and healthy participants. Serum concentrations of Cu, Se and Cr may be independently associated with hypertension. Higher serum ratios of Cu:Zn and Mg:Mn may also be associated with hypertension. Further randomized trials are necessary to elucidate the true relationship between levels of Cu, Se, Cr, Cu:Zn, Mg:Mn and hypertension.

The association between serum copper concentrations and elevated blood pressure in US children and adolescents: National Health and Nutrition Examination Survey 2011-2016

BACKGROUND

Copper is an essential trace metal with potential interest for cardiovascular effects. Few studies have explored the association between copper and blood pressure in children and adolescents.

METHOD

We conducted a cross-sectional analysis of 1242 children and adolescents aged 8-17 years who participated in the 2011 to 2016 National Health and Nutrition Examination Survey. Using 2017 American Academy of Pediatrics guidelines, elevated blood pressure (EBP) was defined as a mean systolic and/or diastolic blood pressure (BP) ≥ 90th percentile for sex, age, and height for children aged 1-12 years and systolic BP ≥ 120 mmHg or diastolic BP ≥ 80 mmHg for adolescent age 13-17 years. Mean serum copper was 114.17 μg/dL.

RESULTS

After multiple adjustments, dose-response analyses revealed that EBP was associated with progressively higher serum copper concentrations in a nonlinear trend. In comparison with the lowest quartile of serum copper concentrations, the adjusted odds of EBP for the highest quartile was 5.26 (95% confidence interval, 2.76-10.03).

CONCLUSION

Our results suggested that high serum copper concentrations were significantly associated with EBP in US children and adolescents.

Traditional Uses, Bioactive Constituents, Biological Functions, and Safety Properties of Oviductus ranae as Functional Foods in China

Oviductus ranae is an animal-based traditional Chinese material widely used as tonics in China for hundreds of years. Various bioactive components are present in OR including proteins, amino acids, steroids, fatty acids, phospholipids, nucleosides, vitamins, hydantoins, and mineral elements. These constituents exert a myriad of biological functions such as immunomodulatory, antioxidant, antifatigue, antiaging, estrogen-like, hepatoprotective, hypolipidemic, antiosteoporotic, antidepressant, antitumor, antitussive, expectorant, anti-inflammatory, and antiasthmatic activities. Unlike other traditional Chinese crude drugs recorded in Chinese Pharmacopoeia, OR is seldom prescribed as medicine but often consumed as nutraceuticals to optimize health. In this review, the traditional uses, bioactive constituents, biological functions, and safety properties of OR as functional foods in China were summarized and discussed. It is expected that this review will provide useful information for anyone who is interested in OR.

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.

Dietary intake and serum and hair concentrations of minerals and their relationship with serum lipids and glucose levels in hypertensive and obese patients with insulin resistance

Inadequate minerals intake, as well as disruption of some metabolic processes in which microelements are cofactors, are suggested to lead to the development of hypertension. The role of minerals in the pathogenesis of hypertension still remains to be explained. In the present study, we sought to determine associations between serum and hair mineral concentrations and serum lipids and glucose levels. Forty obese hypertensive subjects with insulin resistance and 40 healthy volunteers were recruited in the study. Blood pressure, BMI, and insulin resistance were recorded in all subjects. Levels of lipids, glucose, sodium and potassium, iron, copper, zinc, magnesium, and calcium were assessed in serum. Iron, copper, zinc, magnesium, and calcium were assessed in hair. Dietary intake of the analyzed minerals was estimated. We found distinctly higher concentrations of serum iron and serum and hair calcium as well as markedly lower levels of hair zinc in the hypertensive subjects. The study group manifested also significantly lower daily intake of calcium, magnesium, and iron. We observed a relationship between the concentrations of iron, zinc, and copper in serum and hair and high and low range of cholesterol, triglycerides, and glucose serum levels in the studied patients. Moreover, this study demonstrated significant correlation between serum and hair concentrations of selected minerals and their dietary intake and levels of serum lipids and glucose and blood pressure in the study and the control groups. The obtained results seem to indicate the association between lipid and glucose metabolism and iron, copper, zinc, and calcium concentrations in blood and hair of hypertensive and obese patients with insulin resistance.

Trace elemental analysis of normal, benign hypertrophic and cancerous tissues of the prostate gland using the particle-induced X-ray emission technique

Trace elemental analysis was carried out in the tissue samples of normal, benign hypertrophic and carcinoma prostate using the particle-induced X-ray emission technique. A proton beam of 3 MeV energy was used to excite the samples. The elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Se, and Br were identified and their concentrations were estimated. It is observed that in benign tissues the concentrations of Cl, K, Zn, and Se are lower (P<0.05) and those of Cr, Fe, Ni, and Cu are higher (P<0.05 ) than in normal tissues. The concentrations of K, Ca, Zn, Se, and Br are lower (P<0.01) and those of Ti, Cr, Mn, Fe, Ni, and Cu are significantly higher (P<0.0005) in cancerous tissues than in normal tissues. Free radicals generated by elevated levels of Cr, Fe, Ni, and Cu possibly initiate and promote prostate cancer by oxidative DNA damage. The excess Cu levels in cancerous tissues support the fact that Cu promotes cancer through angiogenesis. The higher levels of Fe observed in cancerous tissues might be a consequence of tumor growth through angiogenesis. Significantly higher levels of Ni and Cr observed in carcinoma tissues support the well-established role of Ni and Cr as carcinogens. It is likely that the observed low levels of Zn and Se in cancerous tissues lead to the development of prostate cancer owing to a decrease in antioxidative defense capacity and impaired immune function of cells and also suggest that the inability to retain high levels of Zn and Se may possibly be an important factor in the development and progression of malignant prostate cells. In order to substantiate the observed elevated or deficient levels of trace elements in initiating, promoting, and inhibiting prostate cancer, several cellular and molecular studies are required.