The Impact of Serum Zinc Levels on Abdominal Fat Mass in Hemodialysis Patients

Association of Plasma Zinc and Copper with Body Composition, Lipids and Inflammation in a Cross-Sectional General Population Sample from Germany

We aimed to relate circulating plasma zinc and copper to a broad spectrum of adiposity-related traits in a cross-sectional Northern German study (n = 841, 42% female, age: 61 ± 12 years). Zinc and copper were measured by inductively coupled plasma-mass spectrometry. Subcutaneous (SAT) and visceral (VAT) adipose tissue and liver fat were derived from 534 and 538 participants, respectively, via magnet resonance imaging. Associations were assessed using multivariable-adjusted linear regression analysis. An increase per one standard deviation (SD) in zinc was associated with direct linear increases in body mass index (BMI) (1.17%; 95% confidence interval (95%CI) 0.15-2.20%), waist circumference (0.85%; 95%CI 0.04-1.67%) and waist-to-hip ratio (0.64%; 95%CI 0.18-1.09%). A 1-SD increment in copper was directly associated with BMI (1.64%; 0.41-2.88%) and waist circumference (1.22%; 95%CI 0.25-2.20%) but not waist-to-hip ratio. Independent of fat intake, zinc displayed associations with VAT (5.73%; 95%CI 2.04-9.56%) and with liver fat (3.84%; 95%CI 1.49-6.25%), the latter association being also independent of BMI. Copper was directly associated with SAT (4.64%; 95%CI 0.31-9.15%) before accounting for BMI, but showed no association with VAT or liver fat. Observed associations suggest a possible relevance of zinc and copper to adiposity. Particularly zinc displayed associations with traits of abdominal adiposity and liver fat.

Clinical Significance of Trace Element Zinc in Patients with Chronic Kidney Disease

The trace element zinc is essential for diverse physiological processes in humans. Zinc deficiency can impair growth, skin reproduction, immune function, maintenance of taste, glucose metabolism, and neurological function. Patients with chronic kidney disease (CKD) are susceptible to zinc deficiency, which is associated with erythropoiesis-stimulating agent (ESA) hypo-responsive anemia, nutritional problems, and cardiovascular diseases as well as non-specific symptoms such as dermatitis, prolonged wound healing, taste disturbance, appetite loss, or cognitive decline. Thus, zinc supplementation may be useful for the treatment of its deficiency, although it often causes copper deficiency, which is characterized by several severe disorders including cytopenia and myelopathy. In this review article, we mainly discuss the significant roles of zinc and the association between zinc deficiency and the pathogenesis of complications in patients with CKD.

Evaluation of visceral adiposity index with cardiovascular risk factors, biomarkers in postmenopausal women to predict cardiovascular disease: A 10 year study

BACKGROUND AND AIM

Visceral adiposity index (VAI) is reportedly beneficial in predicting cardiovascular disease (CVD) and metabolic syndrome (MetS). However, long-term studies analyzing the efficacy of VAI in the prediction of CVD risk are limited. The relationship between VAI and electrolytes is unclear. This study aimed to determine if VAI can be used as a predictor of CVD and provide early diagnosis possibility for future CVD patients. Moreover, the impact of biomarkers and electrolytes on VAI therefore indirect relation to CVD was analyzed.

METHODS

Postmenopausal women (aged >40 years) admitted to our hospital in 2011 were included and categorized into two groups according to their VAI scores: mild/moderate and severe. Groups were compared with insulin resistance, biochemical parameters, and anthropometric measurements. Patients have been reached out after 10 years and questioned for additional disease and cardiovascular risk. Statistical Package for Social Sciences (SPSSv22.0) was used for data analysis. The p < 0.05 value was considered significant.

RESULTS

Mean VAI score of patients with MetS (7.30 ± 4.75) was significantly higher than without MetS (2.95 ± 1.05) (p < 0.01). Serum magnesium level was found significantly lower in the severe group. Serum zinc (Zn) and hsCRP levels were higher in the severe group. Correlation analysis showed significant positive correlations between VAI scores and total cholesterol (r = 0.289, p < 0.05), Zn (r = 0.397, p < 0.01), fasting insulin (r = 0.455, p < 0.01) and no significant association with the 10-year CVD incidence (OR: 1.034 (0.888-1.203); p = 0.668).

CONCLUSION

Previous VAI results cannot assist in predicting the 10-year CVD risk. Additionally, including measurements of serum Zn, total cholesterol, fasting insulin, and FBG levels are reasonable approach for managing postmenopausal women with unfavorable CVD risk profiles.

Association between zinc and body composition: An integrative review

BACKGROUND

Zinc deficiency is related to lean body mass reduction, fat deposition, and obesity. Zinc acts in catalytic, structural, and regulatory functions, being an essential micronutrient to humans. It is crucial for maintaining lean body mass, synthesizing nucleic acids and proteins, and forming new tissues. Pre-existing zinc deficiency may contribute to obesity due to its relationship with fat deposition associated with short stature. This integrative review aims to analyze the association between zinc and body composition, hitherto very poorly established in previous studies.

MATERIAL AND METHODS

The electronic databases utilized in this review were PubMed and Web of Science. We identified titles and abstracts from 1178 articles relating to zinc and body composition that were published in the last ten years. After duplicates were removed, the reference lists of relevant reviews were checked, and 47 articles were obtained by manual search.

MAIN FINDINGS AND CONCLUSIONS

The articles were transversal or longitudinal studies, clinical trials, randomized controlled trials, reviews, systematic reviews, and meta-analysis. Although there was heterogeneity among the methodologies, the existence of an association between zinc and body composition was predominant among the studies. All articles concluded that zinc had positive effects on proteogenesis. Moreover, zinc metabolism is dysregulated in obese individuals, whose mechanisms remain controversial.

Zinc Deficiency, Plasma Fatty Acid Profile and Desaturase Activities in Hemodialysis Patients: Is Supplementation Necessary?

Background: Desaturation and elongation are critical processes in endogenous metabolic fatty acid pathways. Zinc (Zn) is a cofactor for desaturases and elongases enzymes. There is limited evidence regarding the relationships between biomarkers of Zn status, nutritional intake, plasma phospholipid fatty acid profile and clinical outcomes among patients undergoing hemodialysis (HD). Objective: To examine the relationships between dietary and serum levels of Zn and Cu/Zn ratio and to explore associations of these micronutrients with PUFA profile and estimated desaturase and elongase enzyme activities in serum phospholipids among HD patients. Methods: This study included 40 adult patients undergoing hemodialysis treatment. Repeated 24-h recalls were applied for dietary intake assessment. Serum concentration of Zn and Cu were determined using inductively coupled plasma mass spectrometry and fatty acid composition by gas-liquid chromatography. Desaturase and elongase activities were calculated from product-precursor fatty acid ratios. Results: Inadequate dietary Zn intake was found in 55% of HD patients. They all had serum Zn concentration below the reference value of 60 μg/dL (mean 38.8 ± 7.72 μg/dL). Adequate zinc intake was accompanied with significantly higher intake of energy, total fats, SFA, MUFA and proteins. There was no correlation between Zn serum status and Zn intake estimates. Serum Cu/Zn ratio was high, (2.76 ± 0.68), directly and significantly associated with HD period, CRP, BMI, VFA, and inversely with Kt/V, albumin, iron, and iPTH. The n-6/n-3 ratio in plasma phospholipids was elevated (12.25 ± 3.45) and patients with inadequate Zn intake had lower n-3 PUFA intake and status compared to those with adequate intake. Serum Zn concentrations were inversely correlated with linoleic/dihomo-γ-linolenic acid ratio (LA/DGLA) (p = 0.037), related to D6-desaturase activity (p = 0.033) and directly with DGLA relative abundances (p = 0.024). Cu status was inversely associated with EPA level (p = 0.03) and estimates of elongase activity (p = 0.001). Furthermore, positive relationship was found between the Cu/Zn ratio and determined elongase value (p = 0.01). Conclusion: Findings of this study underpin the high prevalence of Zn deficiency and inadequate n-3 PUFA intake and status among subjects undergoing HD. The results obtained indicate that the assessment of Zn status should be a standard parameter of nutritional status screening in HD patients while emphasizing the importance of Cu/Zn determination. Although further research is warranted, Zn and-n-3 PUFA supplementation in HD patients might be beneficial for the prevention and attenuation of adverse health outcomes.

Association between Serum Zinc Levels and Clinical Index or the Body Composition in Incident Hemodialysis Patients

Background: The relationships between serum zinc levels and body composition or clinical outcomes of incident hemodialysis (HD) patients remain unclear. Methods: This prospective observational study examined the relationships between serum zinc levels and clinical indexes, including body composition, in 142 incident HD patients using a bioelectrical impedance analysis. Patients were divided into three groups according to baseline serum zinc levels: tertile, <45, 45–59, and ≥60 µg/dL. The reference group was set as ≥60 µg/dL. Cox’s regression analysis was performed to investigate the relationships between serum zinc categories and cardiovascular events and all-cause mortality after adjustments for potential confounders. Results: Serum zinc levels positively correlated with the nutritional index and negatively correlated with fluid volume markers. In a mean follow-up of 2.5 years, there were 20 cases of cardiovascular events and 15 of all-cause mortality. In the Cox’s regression analysis for cardiovascular events and all-cause mortality, the hazard ratio increased with a decrease in serum zinc levels, but was not significant. Conclusion: Serum zinc levels were associated with nutritional and fluid volume markers in incident HD patients. To clarify the relationship between serum zinc levels and cardiovascular events or mortality, further studies with a larger number of cases will be necessary.