Hair magnesium, but not serum magnesium, is associated with left ventricular wall thickness in hemodialysis patients

External interference from ambient air pollution on using hair metal(loid)s for biomarker-based exposure assessment

Hair metal(loid)s are often measured as biomarkers to evaluate population internal exposure, however, hair samples could be easily contaminated by ambient particulate matter (PM) pollution. Here, we evaluated the potential external interference from ambient PM pollution on using hair metal(loid)s for population biomarker-based exposure assessment. The raw hair samples were strictly washed and placed under various indoor and outdoor scenarios for ~6 months at sites with high PM pollution. The contaminated hair was then washed using the same method. A total of 33 hair elements were quantified by inductively coupled plasma-mass spectrometry. The surface residual PM on hair after washing was observed by scanning electron microscopy. In addition, we chose a practical exposure scenario including 77 housewives in Shanxi Province, China for validation. The results for the hair exposure experiment revealed that external contamination of some elements that had relatively high concentrations in hair was generally mild in both indoor and outdoor exposure scenarios (i.e., Zn, Mg, Se, Fe, Sr, Ti, Mn, Sn, Ge, U, Co, Mo, and As). A relatively higher external contamination of other elements (e.g., Al, Cr, Pb, Cd, Li, and most rare earth elements (REEs)) was observed, especially for those elements with relatively low hair concentrations (e.g., Cd, and REEs) in the outdoor environment. This finding was due mainly to some small ambient PM not being fully removed by the current washing strategy when the hair sample was heavily contaminated. However, results from practical exposure scenario of the housewives showed that there were overall no significant differences of hair metal(loid)s between the housewives using coal and clean energy for cooking. We concluded that the external interference on hair internal metal(loid) analysis could be negligible when hair was efficiently washed, especially for population with relatively longer indoor activities. It is therefore promising to use hair analysis for their population exposure assessment.

The Association between Mineral and Trace Element Concentrations in Hair and the 10-Year Risk of Atherosclerotic Cardiovascular Disease in Healthy Community-Dwelling Elderly Individuals

This cross-sectional analysis included 137 Korean subjects aged 60⁻79 years. All subjects underwent anthropometric measurements and laboratory tests. Scalp hair samples were obtained from each individual, the concentrations of 36 minerals and trace elements were analyzed, and 16 ratios of elements were calculated. ASCVD risk was estimated using pooled cohort ASCVD risk assessment equations for 10-year risk profiles. The 137 subjects were divided into three risk groups: low (<5%, n = 28), intermediate (5% to <7.5%, n = 21), and high (≥7.5%, n = 88) risk groups. After adjusting for obesity (BMI ≥ 25 kg/m²) and sex, Na concentration (mg%) in hair was significantly lower in the low-risk (13.91 ± 7.02) than in the intermediate-risk (47.18 ± 8.08) and high-risk (36.76 ± 3.95) groups (p for trend = 0.024). The concentration of K (mg%) in hair was also positively associated with the severity of ASCVD risk (10.50 ± 8.37, 23.62 ± 9.63, 33.31 ± 4.71, respectively; p for trend = 0.017), but their differences were not statistically significant (p = 0.059). By contrast, the levels of Co, U, and Hg, and the Ca/P and Ca/Mg ratios, were negatively correlated with the severity of ASCVD risk (p for trend < 0.05). Mean Na concentration in hair was significantly lower in the low-risk than in the other risk groups. By contrast, Co, U, and Hg concentrations showed significant negative associations with risk severity. Further studies are needed to assess whether dietary modification for trace elements could lower the risk of ASCVD.

Dietary intervention with a specific micronutrient combination for the treatment of patients with cardiac arrhythmias: the impact on insulin resistance and left ventricular function

Background

Cardiac arrhythmias (CA) are very common and may occur with or without heart disease. Causes of these disturbances can be components of the metabolic syndrome (MetS) or deficits of micronutrients especially magnesium, potassium, B vitamins and coenzyme Q10. Both causes may also influence each other. Insulin resistance (IR) is a risk factor for diastolic dysfunction. One exploratory outcome of the present pilot study was to assess the impact of a dietary intervention with specific micronutrients on the lowering of IR levels in patients with CA with the goal to improve the left ventricular (LV) function.

Methods

This was a post hoc analysis of the randomized double blind, placebo-controlled pilot study in patients with CA (VPBs, SVPBs, SV tachycardia), which were recruited using data from patients who were 18–75 years of age in an Outpatient Practice of Cardiology. These arrhythmias were assessed by Holter ECG and LV function by standard echocardiography. Glucose metabolism was measured by fasting glucose, fasting insulin level and the Homeostasis Model Assessment of IR (HOMA-IR) at baseline and after 6 weeks of dietary supplementation.

Results

A total of 54 randomized patients with CA received either a specific micronutrient combination or placebo. Dietary intervention led to a significant decrease in fasting insulin ≥58 pmol/l (p = 0.020), and HOMA-IR (p = 0.053) in the verum group after 6 weeks. At the same time, parameters of LV diastolic function were improved after intervention in the verum group: significant reduction of LV mass index (p = 0.003), and in tendency both a decrease of interventricular septal thickness (p = 0.053) as well as an increase of E/A ratio (p = 0.051). On the other hand, the premature beats (PBs) were unchanged under verum.

Conclusions

In this pilot study, dietary intervention with specific micronutrient combination as add-on to concomitant cardiovascular drug treatment seems to improve cardio metabolic health in patients with CA. Further studies are required.

Study registration

The study was approved by the Freiburg Ethics Commission International and was retrospectively registered with the U.S. National Institutes of Health Clinical Trials gov ID NCT 02652338 on 16 December 2015.

Clinical aspects of magnesium physiology in patients on dialysis

Magnesium balance is infrequently discussed in the dialysis population, and the clinical consequences of derangements in magnesium homeostasis are incompletely understood. There is an association between hypomagnesemia and adverse outcomes including increases in cardiovascular disease and mortality, while elevated magnesium levels have also been linked with complications such as osteomalacia. In this review, we discuss the features of magnesium physiology relevant to dialysis patients and provide an updated summary of the literature linking magnesium derangements with bone disease, cardiovascular disease, sudden cardiac death, and mortality.

Magnesium Status in Alzheimer's Disease: A Systematic Review

The interest in poor magnesium (Mg) status as risk factor for Alzheimer's disease (AD) is increasing due to its antioxidant and neuroprotective properties. A systematic PubMed literature search of studies investigating Mg status was undertaken comparing AD to healthy controls (HCs) or patients with medical illness (medical controls [MCs]). Standardized mean differences (SMDs) ± 95% confidence intervals (CIs) were calculated for all outcomes. Of 192 potentially eligible studies, 13 were included (559 patients with AD, 381 HCs, and 126 MCs). Compared to HCs, patients with AD had significantly lower Mg in cerebrospinal fluid (2 studies; SMD = -0.35;P= .02) and in hair (2 studies; SMD = -0.75;P= .0001). No differences between AD and controls were evident for serum Mg. In conclusion, AD seems to be associated with a lower Mg status when compared to HCs, while the scarcity of studies limited the findings about MCs.

Serum β2-microglobulin correlates positively with left ventricular hypertrophy in long-term hemodialysis patients

BACKGROUND/AIMS

β2-Microglobulin (β2-MG) is a major protein component of dialysis-related amyloidosis. In long-term hemodialysis (HD) patients, β2-MG amyloid deposits not only in osteoarticular tissues, but also in systemic tissues, including the heart. The purpose of this study was to investigate the relationship between serum β2-MG concentrations and echocardiographic parameters in long-term HD patients in a cross-sectional study.

METHODS

Measurement of serum β2-MG concentrations and echocardiography were performed in 251 patients who had undergone HD therapy for more than 10 years.

RESULTS

The left ventricular mass index (LVMI) of the higher serum β2-MG (≥30 mg/l) group was significantly higher than that of the lower serum β2-MG (<30 mg/l) group (151.5 ± 45.7 vs. 137.0 ± 44.5 g/m(2), p = 0.020). In simple regression analyses, serum β2-MG concentrations correlated significantly and positively with interventricular septum thickness (IVST) (r = 0.215, p < 0.001), posterior left ventricular wall thickness (PWT) (r = 0.249, p < 0.001), left ventricular wall thickness (LVWT) (r = 0.252, p < 0.001), relative wall thickness (RWT) (r = 0.153, p = 0.015) and LVMI (r = 0.171, p = 0.007). Multiple regression analyses revealed that serum β2-MG concentrations correlated significantly and positively with IVST, PWT, LVWT and RWT.

CONCLUSION

Serum β2-MG concentrations correlated significantly and positively with the echocardiographic parameters of left ventricular hypertrophy (LVH) in long-term HD patients. Thus, deposition of β2-MG amyloid in the heart may be associated with LVH progression.

Assessment of infantile mineral imbalances in autism spectrum disorders (ASDs)

The interactions between genes and the environment are now regarded as the most probable explanation for autism. In this review, we summarize the results of a metallomics study in which scalp hair concentrations of 26 trace elements were examined for 1,967 autistic children (1,553 males and 414 females aged 0-15 years-old), and discuss recent advances in our understanding of epigenetic roles of infantile mineral imbalances in the pathogenesis of autism. In the 1,967 subjects, 584 (29.7%) and 347 (17.6%) were found deficient in zinc and magnesium, respectively, and the incidence rate of zinc deficiency was estimated at 43.5% in male and 52.5% in female infantile subjects aged 0-3 years-old. In contrast, 339 (17.2%), 168 (8.5%) and 94 (4.8%) individuals were found to suffer from high burdens of aluminum, cadmium and lead, respectively, and 2.8% or less from mercury and arsenic. High toxic metal burdens were more frequently observed in the infants aged 0-3 years-old, whose incidence rates were 20.6%, 12.1%, 7.5%, 3.2% and 2.3% for aluminum, cadmium, lead, arsenic and mercury, respectively. These findings suggest that infantile zinc- and magnesium-deficiency and/or toxic metal burdens may be critical and induce epigenetic alterations in the genes and genetic regulation mechanisms of neurodevelopment in the autistic children, and demonstrate that a time factor "infantile window" is also critical for neurodevelopment and probably for therapy. Thus, early metallomics analysis may lead to early screening/estimation and treatment/prevention for the autistic neurodevelopment disorders.