Enhanced zinc consumption prevents cadmium-induced alterations in lipid metabolism in male rats

Effects of Zinc Supplementation on Inflammatory Status and Nonalcoholic Steatohepatitis in Overweight or Obese Children: a Randomized Clinical Trial

The purpose of the present clinical trial was to determine the impact of zinc supplementation on serum liver enzymes, steatosis severity, lipid profile, and inflammatory status in overweight or obese children with nonalcoholic steatohepatitis (NASH). This randomized controlled trial was conducted by enrolling 60 children with NASH, aged 10-18 years old. The participants were randomly assigned to two groups that received either 30 mg/day of elemental zinc or placebo for 16 weeks. The severity of liver steatosis was evaluated using liver ultrasonography. Fasting blood samples were collected from each patient at the beginning and after 16 weeks of intervention to measure biochemical parameters. Following a 16-week intervention, zinc supplementation compared with placebo significantly decreased serum alanine aminotransferase (ALT) concentrations and high-sensitivity C-reactive protein and considerably enhanced HDL-cholesterol values. However, zinc intake had no considerable impact on aspartate aminotransferase, the severity of liver steatosis, anthropometric parameters, and other lipid indices versus the placebo group. Overall, zinc supplementation showed a promising impact on serum ALT, HDL-cholesterol, and inflammatory status in overweight or obese children suffering from NASH. Zinc supplementation may be a new strategy for the amelioration of NASH in overweight or obese children. This trial has been registered on the Iranian website for registration of clinical trials with the special ID of IRCT20200531047614N1 ( https://www.irct.ir/trial/48543 ).

Associations of urinary zinc exposure with blood lipid profiles and dyslipidemia: Mediating effect of serum uric acid

The relationship between zinc (Zn) exposure and abnormal blood lipids including dyslipidemia is contentious. Serum uric acid (SUA) has been reported to be correlated to both Zn exposure and dyslipidemia. The underlying mechanisms of Zn exposure associated with blood lipids and the mediating effects of SUA remain unclear. Therefore, this study analyzed the data from Chinese 2110 adults (mean age: 59.0 years old) in rural areas across China to explore the associations of Zn exposure with blood lipid profiles and dyslipidemia, and to further estimate the mediating effects of SUA in these relationships. The study data showed that urinary Zn was associated with increased levels of blood lipid components triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C). Moreover, an increased risk of dyslipidemia was observed in the study participants who had higher urinary Zn levels. Compared with the first quartile, the fourth quartile of urinary Zn concentration corresponded to the increase of TG (β = 0.20, 95 % CI: 0.12, 0.28), LDL-C (β = 0.06, 95 % CI: 0.01, 0.10) and dyslipidemia risk (OR = 2.16, 95 % CI: 1.50, 3.10), respectively. Elevated urinary Zn was also associated with higher levels of SUA and hyperuricemia risk. The SUA levels were positively related to total cholesterol (TC), TG, LDL-C levels and dyslipidemia risk. Mediation analyses revealed that SUA mediated 31.75 %, 46.16 % and 19.25 % of the associations of urinary Zn with TG, LDL-C levels and dyslipidemia risk, respectively. The subgroup and sensitivity analyses confirmed the positive associations between urinary Zn and blood lipid profiles and the mediating effect of SUA. The national population-based study further enhanced our understanding of the associations between Zn exposure and blood lipid profiles and mediating effect of SUA among generally healthy, middle-aged, and elderly individuals.

Epigenome-wide perspective of cadmium-associated DNA methylation and its mediation role in the associations of cadmium with lipid levels and dyslipidemia risk

BACKGROUND

Studies demonstrated the associations of cadmium (Cd) with lipid levels and dyslipidemia risk, but the mechanisms involved need further exploration.

OBJECTIVES

We aimed to explore the role of DNA methylation (DNAM) in the relationship of Cd with lipid levels and dyslipidemia risk.

METHODS

Urinary cadmium levels (UCd) were measured by inductively coupled plasma mass spectrometry, serum high-density lipoprotein (HDL), total cholesterol, triglyceride, and low-density lipoprotein were measured with kits, and DNAM was measured using the Infinium MethylationEPIC BeadChip. Robust linear regressions were conducted for epigenome-wide association study. Multivariate linear and logistic regressions were performed to explore the associations of UCd with lipid levels and dyslipidemia risk, respectively. Mediation analyses were conducted to explore potential mediating role of DNAM in the associations of Cd with lipid levels and dyslipidemia risk.

RESULTS

UCd was negatively associated with HDL levels (p = 0.01) and positively associated with dyslipidemia (p < 0.01). There were 92/11 DMPs/DMRs (FDR<0.05) associated with UCd. Cd-associated DNAM and pathways were connected with cardiometabolic diseases and immunity. Cg07829377 (LINC01060) mediated 42.05%/22.88% of the UCd-HDL/UCd-dyslipidemia associations (p = 0.02 and 0.01, respectively).

CONCLUSIONS

Cadmium caused site-specific DNAM alterations and the associations of UCd with lipid levels and dyslipidemia risk may be partially mediated by DNAM.

Associations of cadmium exposure with risk of metabolic syndrome and its individual components: a meta-analysis

Data directly associating cadmium (Cd) with metabolic syndrome (MetS) are sparse and inconsistent. We aimed to quantitatively assess the association of Cd exposure with risk of MetS and its individual components. Literature searching was performed in PubMed, EMBASE, and MEDLINE-OVID through September, 2021. Weighted odds ratios (ORs) for MetS and its components were pooled by comparing the highest to the lowest category of Cd exposure using random-effects models. Eleven (10 from Asia and 1 from the US) cross-sectional studies (33,887 participants and 7176 cases) were identified. Overall, Cd exposure was not associated with risk of MetS [OR: 1.08, 95% confidence interval (CI): 0.92, 1.28]. However, the association became significant when pooling Asian studies (OR: 1.18, 95% CI: 1.02, 1.35), and it was more pronounced with Cd measured in blood (OR: 1.24, 95% CI: 1.05, 1.45). Additionally, Cd exposure was significantly associated with reduced HDL-cholesterol (OR: 1.27, 95% CI: 1.05, 1.54) and elevated triglyceride (OR: 1.17, 95% CI: 1.05, 1.30), but not other components. This meta-analysis indicates that Cd exposure is associated with risk of MetS among Asian populations, which is mainly explained by Cd's association with dyslipidemia. Further studies are needed to better understand the mechanism of action.

Contaminant Metals and Cardiovascular Health

A growing body of research has begun to link exposure to environmental contaminants, such as heavy metals, with a variety of negative health outcomes. In this paper, we sought to review the current research describing the impact of certain common contaminant metals on cardiovascular (CV) health. We reviewed ten metals: lead, barium, nickel, chromium, cadmium, arsenic, mercury, selenium, zinc, and copper. After a literature review, we briefly summarized the routes of environmental exposure, pathophysiological mechanisms, CV health impacts, and exposure prevention and/or mitigation strategies for each metal. The resulting article discloses a broad spectrum of pathological significance, from relatively benign substances with little to no described effects on CV health, such as chromium and selenium, to substances with a wide-ranging and relatively severe spectrum of CV pathologies, such as arsenic, cadmium, and lead. It is our hope that this article will provide clinicians with a practical overview of the impact of these common environmental contaminants on CV health as well as highlight areas that require further investigation to better understand how these metals impact the incidence and progression of CV diseases.

Do blood metals influence lipid profiles? Findings of a cross-sectional population-based survey

Dyslipidemia, an imbalance of lipids and a major risk factor for cardiovascular disease, has been associated with elevated blood and urine levels of several heavy metals. Using data from a Canadian Health Measures Survey (CHMS), we tested associations between blood levels of cadmium, copper, mercury, lead, manganese, molybdenum, nickel, selenium, and zinc, and the lipids triglycerides (TG), total cholesterol (TC), low density lipoproteins (LDL), high density lipoproteins (HDL) and apolipoproteins A1 (APO A1), and B (APO B). All adjusted associations between single metals and lipids were positive and significant, except for APO A1 and HDL. The joint effect of an interquartile range increase in heavy metals was positively associated with percentage increases of TC, LDL and APO B of 8.82% (95%CI: 7.06, 10.57), 7.01% (95%CI: 2.51, 11.51) and 7.15% (95%CI: 0.51, 13.78), respectively. Future studies are warranted to determine if reducing environmental exposure to heavy metals favorably influences lipid profiles and the risk of cardiovascular disease.

Disturbed Ratios between Essential and Toxic Trace Elements as Potential Biomarkers of Acute Ischemic Stroke

Background: Cadmium (Cd) and lead (Pb) are known to be two of the metal contaminants that pose the greatest potential threat to human health. The purpose of this research study was to compare the levels of toxic metals (Cd, Pb) in patients with acute ischemic stroke (AIS), with a control group in Podlaskie Voivodeship, Poland. The study also aimed to assess the correlations between toxic metals and clinical data in AIS patients, and to assess the potential effect of smoking. Materials and methods: The levels of mineral components in the collected blood samples were assessed by means of atomic absorption spectrometry (AAS). Results: The Cd blood concentration was significantly higher in AIS patients as compared to the control group. We found that the molar ratios of Cd/Zn and Cd/Pb were significantly higher (p < 0.001; p < 0.001, respectively), when the molar ratios of Se/Pb, Se/Cd, and Cu/Cd were significantly lower (p = 0.01; p < 0.001; p < 0.001, respectively), in AIS patients as compared to control subjects. However, there were no considerable fluctuations in relation to the blood Pb concentration or molar ratios of Zn/Pb and Cu/Pb between our AIS patients and the control group. We also found that patients with internal carotid artery (ICA) atherosclerosis, particularly those with 20–50% ICA stenosis, had higher concentrations of Cd and Cd/Zn, but lower Cu/Cd and Se/Cd molar ratios. In the course of our analysis, we observed that current smokers among AIS patients had significantly higher blood-Cd concentrations, Cd/Zn and Cd/Pb molar ratios, and hemoglobin levels, but significantly lower HDL-C concentrations, Se/Cd, and Cu/Cd molar ratios. Conclusions: Our research has shown that the disruption of the metal balance plays a crucial role in the pathogenesis of AIS. Furthermore, our results broaden those of previous studies on the exposure to Cd and Pb as risk factors for AIS. Further investigations are necessary to examine the probable mechanisms of Cd and Pb in the onset of ischemic stroke. The Cd/Zn molar ratio may be a useful biomarker of atherosclerosis in AIS patients. An accurate assessment of changes in the molar ratios of essential and toxic trace elements could serve as a valuable indicator of the nutritional status and levels of oxidative stress in AIS patients. It is critical to investigate the potential role of exposure to metal mixtures in AIS, due to its public health implications.

Oligochaeta ramosa (Roxb.) Extract Regulates Lipid Metabolism and Exerts Hepatoprotective Effects in Cadmium-Induced Hepatic Injury in Rats

Environmental pollutants present a potential source of toxicity when exposed to humans. The study was aimed at investigating the potential of Oligochaeta ramosa (Roxb.) as a hepatoprotective agent in cadmium-induced hepatotoxicity causing lipid profile disturbance. The aqueous methanolic (30 : 70 v/v) extract of O. ramosa Roxb. (AME.Or) was subjected to preliminary phytochemical analysis, whereas the antioxidant activity of its constituents was investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The hepatoprotective and antihyperlipidemic effects of AME.Or was investigated by dividing animals into five groups (A-E). Animals were either treated with normal saline or CdCl₂ (6.5 mg/kg, intraperitoneally) followed by treatment with silymarin (100 mg/kg), or AME.Or (200 mg/kg) and AME.Or (400 mg/kg) for consecutive three weeks. Blood samples were collected, and the serum lipid profile was assessed on the 11^th and 21^st day of treatment. Histopathological analysis was performed after euthanization. In vitro analysis of AME.Or revealed 64% inhibition as free radicals scavenging potential during DPPH, total phenolic content (TPC) (79.92 mgGAE/g), and total flavonoids content (TFC) (38.75 mgRE/g). The group intoxicated with CdCl₂ showed significantly high (p ≤ 0.05) levels of the liver function indicators and lipid profile than in the control group. The higher dose of AME.Or (400 mg/kg) significantly decreased the aspartate aminotransferase (AST), alanine transferase (ALT), alkaline phosphatase (ALP), total bilirubin (p ≤ 0.001), decreased total cholesterol and triglycerides (p ≤ 0.01) while significantly increased high density lipoprotein (HDL; p ≤ 0.01) as compared to the intoxicated group. The histopathological analysis of the liver revealed signs of necrosis in the intoxicated group, while AME.Or treated groups showed marked improvement. The findings accentuate the therapeutic importance of O. ramosa (Roxb.) as a hepatoprotective remedy.

The Beneficial Impact of Zinc Supplementation on the Vascular Tissue of the Abdominal Aorta under Repeated Intoxication with Cadmium: A Study in an In Vivo Experimental Model

In an in vivo rat model of human exposure to cadmium (Cd; 5 and 50 mg/L, 6 months), whether the supplementation with zinc (Zn; 30 and 60 mg/L, increasing its daily intake by 79% and 151%, respectively) protects against the unfavourable impact of this xenobiotic on the vascular tissue of the abdominal aorta was investigated. The treatment with Cd led to oxidative stress and increased the concentrations of pro-inflammatory interleukin 1β (IL-1β), total cholesterol (TC), triglycerides (TG), and endothelial nitric oxide synthase (eNOS) and decreased the concentration of anti-inflammatory interleukin 10 (IL-10) in the vascular tissue. Cd decreased the expression of intercellular adhesion molecule-1 (ICAM-1), platelet endothelial cell adhesion molecule-1 (PECAM-1), and L-selectin on the endothelial cells. The administration of Zn prevented most of the Cd-induced alterations or at least weakened them (except for the expression of adhesive molecules). In conclusion, Zn supplementation may protect from the toxic impact of Cd on the blood vessels and thus exert a beneficial influence on the cardiovascular system. The increase in the intake of Zn by 79% may be sufficient to provide this protection and the effect is related to the antioxidative, anti-inflammatory, and antiatherogenic properties of this essential element.

Misuse of Cardiac Lipid upon Exposure to Toxic Trace Elements-A Focused Review

Heavy metals and metalloids like cadmium, arsenic, mercury, and lead are frequently found in the soil, water, food, and atmosphere; trace amounts can cause serious health issues to the human organism. These toxic trace elements (TTE) affect almost all the organs, mainly the heart, kidney, liver, lungs, and the nervous system, through increased free radical formation, DNA damage, lipid peroxidation, and protein sulfhydryl depletion. This work aims to advance our understanding of the mechanisms behind lipid accumulation via increased free fatty acid levels in circulation due to TTEs. The increased lipid level in the myocardium worsens the heart function. This dysregulation of the lipid metabolism leads to damage in the structure of the myocardium, inclusive fibrosis in cardiac tissue, myocyte apoptosis, and decreased contractility due to mitochondrial dysfunction. Additionally, it is discussed herein how exposure to cadmium decreases the heart rate, contractile tension, the conductivity of the atrioventricular node, and coronary flow rate. Arsenic may induce atherosclerosis by increasing platelet aggregation and reducing fibrinolysis, as exposure interferes with apolipoprotein (Apo) levels, resulting in the rise of the Apo-B/Apo-A1 ratio and an elevated risk of acute cardiovascular events. Concerning mercury and lead, these toxicants can cause hypertension, myocardial infarction, and carotid atherosclerosis, in association with the generation of free radicals and oxidative stress. This review offers a complete overview of the critical factors and biomarkers of lipid and TTE-induced cardiotoxicity useful for developing future protective interventions.

Cadmium Accumulation in the Goat Liver and Kidney Is Partially Promoted by the Upregulation of Metal Transporter Genes

Metal transporters, including divalent metal-ion transporter-1 (DMT1), Zrt-/Irt-like protein 8 and 14 (ZIP8 and ZIP14), and ferroportin-1 (FPN1), reportedly participate in cellular cadmium (Cd) uptake, but those in farm animals remain unclarified. This study aimed to examine the growth, plasma biochemical indices, Cd accumulation, and expression of metal transporter genes in the liver, kidney, and muscle of goats exposed to rice paddies contaminated with different levels of Cd. Twenty-four goats were randomly assigned across three dietary treatments: 0.23, 0.63, and 1.07 mg of Cd/kg of dry matter (DM) for 60 days. The results showed that dietary Cd exposure increased (p < 0.05) both Cd accumulation and the mRNA expressions of metal transporter genes (DMT1, ZIP, and FPN1) in the liver and kidney but not in the muscle, suggesting dietary Cd exhibited different deposition rates between goat liver, kidney, and muscle. These outcomes suggest that high levels of dietary Cd stimulated the expression of metal transporter genes and thereby enhanced the uptake and accumulation of Cd in the goat liver and kidney. As such, higher Cd concentrations in the liver and kidney observed with Cd diets could be partly explained by upregulation of metal transport genes expression.

Protective Role of the Essential Trace Elements in the Obviation of Cadmium Toxicity: Glimpses of Mechanisms

Cadmium (Cd) is toxic non-essential heavy metal that precipitates adverse health effects in humans and animals. Chelation therapy, the typical treatment for cadmium toxicity, has certain safety and efficacy issues to treat long term cadmium toxicity, in particular. Recent studies have shown that essential trace elements can play important roles in obviating experimental Cd toxicity. This study organizes and reviews the prototypical evidences of the protective effects of essential trace elements against Cd toxicity in animals and attempts to point out the underlying mechanisms. Zinc, selenium, iron, and combinations thereof are reported to be active. The major mechanisms elucidated inter alia are-induction of metallothionein (MT) synthesis and Cd-MT binding (for zinc), modulation of oxidative stress and apoptosis, interference in cadmium absorption and accumulation from body-thereby maintenance of essential metal homeostasis and cytoprotection. Based on the findings, essential trace elements can be recommended for the susceptible population. The application of these trace elements appears beneficial for both the prevention and remediation of long-term Cd toxicity operative via multiple mechanisms with no or minimal adverse effects as compared to the conventional chelation therapy.

An exploratory identification of biological markers of chronic musculoskeletal pain in the low back, neck, and shoulders

Objectives

This study was an in-depth exploration of unique data from a nationally representative sample of adults living in the United States to identify biomarkers associated with musculoskeletal pain.

Methods

We performed secondary analyses of 2003–2004 NHANES data. After a first screening of 187 markers, analyses of 31 biomarkers were conducted on participants aged ≥20 years identified in all counties using the 2000 Census Bureau data (n = 4,742). To assess the association of each biomarker with each pain outcome (acute, subacute and chronic low back, neck, and shoulder pain), analyses were carried out using multivariable logistic regression with adjustments for sex, age and body mass index. Biomarkers were considered as continuous variables and categorized at the median of their distributions.

Results

Pain at any site for ≥24 hours during the past month was reported by 1,214 participants. Of these, 779 mentioned that the pain had lasted for ≥3 months (“chronic pain”). α-carotene, ascorbic acid, β-carotene, mercury and total protein had a statistically significant, inverse association with ≥2 chronic pain sites. Acrylamide, alkaline phosphatase, cadmium, cotinine, glycidamide, homocysteine, retinol, triglycerides and white blood cell count were positively associated with ≥2 chronic pain sites. Few biological markers were associated with acute and subacute pain.

Conclusions

This study identified some biomarkers that were strongly and consistently associated with musculoskeletal pain. These results raise new hypotheses and could have tremendous implications for advancing knowledge in the field. Research on musculoskeletal pain needs to put more effort on the biological dimension of the biopsychosocial model of pain.

Review of cadmium exposure and smoking-independent effects on atherosclerotic cardiovascular disease in the general population

BACKGROUND

Exposure to cadmium (Cd) via food and smoking is associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD). Blood and urine levels of Cd are established biomarkers of exposure.

OBJECTIVES

To review (1) the smoking-independent associations between Cd exposure and ASCVD, including the possible presence of a nonlinear dose-response relationship with Cd exposure and (2) the causal effects of Cd exposure on different stages of atherosclerosis.

METHODS

Narrative review.

RESULTS

Cd confers increased risk of ASCVD and asymptomatic atherosclerosis in the carotid and coronary arteries above B-Cd >0.5 μg/L or U-Cd >0.5 μg/g creatinine, but it has not been shown below a threshold of these exposure levels. Adjustment for smoking does not exclude the possibility of residual confounding, but several studies in never-smoking cohorts have shown associations between Cd and ASCVD, and experimental studies have demonstrated pro-atherosclerotic effects of Cd. Cd accumulates in arterial walls and atherosclerotic plaques, reaching levels shown to have proatherosclerotic effects. Suggested early effects are increased subendothelial retention of atherogenic lipoproteins, which become oxidized, and endothelial dysfunction and damage with increased permeability for monocytes, which in the intima turn to macrophages and then to foam cells. Later, Cd may contribute to plaque rupture and erosion by endothelial apoptosis and degradation of the fibrous cap. Finally, by having prothrombotic and antifibrinolytic effects, the CVD risk may be further increased.

CONCLUSIONS

There is strong evidence that Cd causes ASCVD above a suggested exposure level via mechanisms in early as well as the late stages of atherosclerotic disease.

Immunomodulation by heavy metals as a contributing factor to inflammatory diseases and autoimmune reactions: Cadmium as an example

Cadmium (Cd) represents a unique hazard because of the long biological half-life in humans (20-30 years). This metal accumulates in organs causing a continuum of responses, with organ disease/failure as extreme outcome. Some of the cellular and molecular alterations in target tissues can be related to immune-modulating potential of Cd. This metal may cause adverse responses in which components of the immune system function as both mediators and effectors of Cd tissue toxicity, which, in combination with Cd-induced alterations in homeostatic reparative activities may contribute to tissue dysfunction. In this work, current knowledge concerning inflammatory/autoimmune disease manifestations found to be related with cadmium exposure are summarized. Along with epidemiological evidence, animal and in vitro data are presented, with focus on cellular and molecular immune mechanisms potentially relevant for the disease susceptibility, disease promotion, or facilitating development of pre-existing pathologies.

Gallic acid attenuates cadmium mediated cardiac hypertrophic remodelling through upregulation of Nrf2 and PECAM-1signalling in rats

Gallic acid (GA) is an abundant natural polyphenolic compound found in vegetable and fruits that reduces the cardiac disease risk factor. This study aims to evaluate GA's role on cadmium (Cd) induced cardiac remodelling in experimental rats. Male Wistar rats were exposed to Cd (15 ppm) in drinking water and administered with GA orally (15 mg/kg/d) for 60 days. The results showed that GA regulated the lipid profile and reduced the LDL to 57 % compared with Cd treated rats. GA inhibited cardiac marker enzymes activity of CK-NAC (to 72.7 %) and CK-MB (to 100.3 %). Moreover, GA attenuated lipid peroxidation and enhanced the cardiac glutathione S transferase (GST) activity (89.2 %), glutathione peroxidase (GPx) (87 %), superoxide dismutase (SOD) (88.4 %) and catalase (CAT) activity (86.5 %). Histopathological examination showed that GA impaired the ventricular hypertrophy and fibrotic proliferation induced by Cd in rats. The combination of GA + Cd, decreased the gene expression of ANP (1-fold), BNP (0.5-fold) and β- MHC (0.9-fold). Furthermore, GA significantly reduced the expression of profibrotic (TGF-β) and proinflammatory (MCP-1) gene in Cd intoxicated rats. GA upregulated the expression of Nrf2 (2-fold), HO-1 (3-fold), and PECAM-1 (0.6-fold), which augments the detoxifying enzyme activity and cellular immunity in Cd intoxicated rats. The increased protein expression of Nrf2, PECAM-1 and decreased AKT-1 levels confirmed the mechanical action of GA during the hypertrophic condition. Thus, our results suggest that GA could act as a potential therapeutic agent regulating Nrf2 and PECAM-1 signalling pathways, thereby ameliorating Cd-induced pathological cardiac remodelling.

Cadmium induces triglyceride levels via microsomal triglyceride transfer protein (MTTP) accumulation caused by lysosomal deacidification regulated by endoplasmic reticulum (ER) Ca2+ homeostasis

Cadmium (Cd) exposure induced lipid metabolic disorder with changes in lipid composition, as well as triglyceride (TG) levels. Liver is the main organ maintaining body TG level and previous studies suggested that Cd exposure might increase TG synthesis but reduce TG uptake in liver. However, the effects of Cd exposure on TG secretion from liver and underlying mechanism are still unclear. In the present study, the data revealed that Cd exposure increased TG levels in the HepG2 cells and the cultured medium by increasing the expression of microsomal triglyceride transfer protein (MTTP), which was abrogated by siRNA knockdown of MTTP. MTTP was synergistically accumulated after Cd exposure or treated with proteasome inhibitor MG132 and lysosome inhibitor chloroquine (CQ), which suggested the Cd increased MTTP protein stability by inhibiting both the proteasome and the lysosomal protein degradation pathways. In addition, our results demonstrated that Cd exposure inhibited the lysosomal acidic degradation pathway through disrupting endoplastic reticulum (ER) Ca²⁺ homeostasis. Cd-induced MTTP protein and TG levels were significantly reduced by pretreatments of BAPTA/AM chelation of intracellular Ca²⁺, 2-APB inhibition of ER Ca²⁺ release channel inositol 1,4,5-trisphosphate receptor (IP3R) and CDN1163 activation of ER Ca²⁺ reuptake pump sarcoplasmic reticulum Ca²⁺-ATPase (SERCA). These results suggest that Cd-induced ER Ca²⁺ release impaired the lysosomal acidity, which associated with MTTP protein accumulation and contributed to increased TG levels.

Effects of excessive dietary zinc or zinc/cadmium and tapeworm infection on the biochemical parameters in rats

The main objective of this study was to determine which biochemical blood parameters can serve as indicators of Zn or Zn/Cd burden and tapeworm infection. This study was performed on 44 Wistar male rats during a 6-week period, when rats were or were not fed a zinc/cadmium rich diet and were or were not infected with tapeworms (Hymenolepis diminuta). Total protein, albumin, urea, glucose, triacylglycerols, non-esterified fatty acids, cholesterol, alkaline phosphatase, aspartate aminotransferase, uric acid, Mg, Ca, P and Zn levels were analysed. Control rats with tapeworm infection had significantly higher (p ≤ 0.05) total protein, urea and phosphorus concentrations than did rats unaffected by any experimental factor. Rats given overdoses of zinc lactate exhibited significantly lower glucose levels than did the other rats, especially those infected with tapeworms. Low glucose level in uninfected rats indicate a Zn overdose; high doses of zinc lactate likely decrease levels of glucose via cortisol, which is released during stress. Rats fed the Zn/Cd hyperaccumulating plant Arabidopsis halleri and infected with tapeworms had significantly higher (p ≤ 0.01) cholesterol and urea levels but lower zinc, triacylglycerol, and alkaline phosphatase levels than did rats fed the same diet but free of tapeworms. The increase of alkaline phosphatase level in uninfected rats may indicate both Zn/Cd burden and rat liver damage. Overall, this study not only supports the theory that H. diminuta can serve as a promising model for helminth therapy of the host mammal but also confirmed that this tapeworm is capable to protect somehow the host organism from the harmful effects of heavy metals.

Protective effects of selenium and zinc against potassium dichromate-induced thyroid disruption, oxidative stress, and DNA damage in pregnant Wistar rats

Hexavalent chromium (CrVI) is an environmental pollutant and an endocrine-disrupting metal. Se and Zn are essential trace elements, known to play a crucial role in thyroid homeostasis. However, there is a lack of data reporting thyrotoxicity during gestation. In this study, we investigated the protective effects of selenium and zinc against potassium dichromate-induced thyrotoxicity in pregnant Wistar rats. Thirty pregnant Wistar rats were divided into control and four treated groups receiving subcutaneously (s.c) on the 3rd day of pregnancy, K2Cr2O7 (10 mg/kg, s.c) alone, or in association with Se (0.3 mg/kg, s.c), ZnCl2 (20 mg/kg, s.c), or both of them simultaneously. The hormonal profile, oxidative stress biomarkers, DNA damage, and histological modifications were evaluated. Our main findings showed that K2Cr2O7 promoted hypothyroidism, oxidative stress, genotoxicity, and histological alterations in the thyroid gland. The co-treatment with Se or ZnCl2 has mitigated K2Cr2O7-induced thyrotoxicity in pregnant Wistar rats by exhibiting antioxidant and genoprotective effects. However, the combined co-treatment of both of them was less thyroprotective, and therefore, further investigations on the synergetic interaction of Se and Zn against CrVI toxicity using different doses and exposure routes are required.

Zinc as a countermeasure for cadmium toxicity

Cadmium (Cd) is an important environmental pollutant and long-term Cd exposure is closely related to autoimmune diseases, cancer, cardiovascular diseases (CVD), and hepatic dysfunction. Zinc (Zn) is an essential metal that plays key roles in protein structure, catalysis, and regulation of their function. Numerous studies have shown that Zn can reduce Cd toxicity; however, the underlying mechanisms have not been extensively explored. Preclinical studies have revealed direct competition for sarcolemmal uptake between these two metals. Multiple sarcolemmal transporters participate in Cd uptake, including Zn transporters, calcium channels, and DMT1 (divalent metal transporter 1). Zn also induces several protective mechanisms, including MT (metallothionein) induction and favorable redox homeostasis. This review summarizes current knowledge related to the role of Zn and metal transporters in reducing Cd toxicity and discusses potential future directions of related research.

Association of multiple metals with lipid markers against different exposure profiles: A population-based cross-sectional study in China

We sought to evaluate whether essential and toxic metals are cross-sectionally related to blood lipid levels using data among adults from Shimen (n = 564) and Huayuan (n = 637), two counties with different exposure profiles in Hunan province of China. Traditional and grouped weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were performed to assess association between exposure to a mixture of 22 metals measured in urine or plasma, and lipid markers. Most of the exposure levels of metals were significantly higher in Shimen area than those in Huayuan area (all P-values < 0.001). Traditional WQS regression analyses revealed that the WQS index were both significantly associated with lipid markers in two areas, except for the HDL-C. Grouped WQS revealed that essential metals group showed significantly positive associations with lipid markers except for HDL-C in Huayuan area, while toxic metals group showed significantly negative associations except for HDL-C and LDL-C in Huayuan area. There were no significant joint effects, but potential non-linear relationships between metals mixture and TC or LDL-C levels were observed in BKMR analyses. Although consistent significantly associations of zinc and titanium with TG levels were found in both areas, the metals closely related to other lipid markers were varied by sites. Additionally, the BKMR analyses revealed an inverse U shaped association of iron with LDL-C levels and interaction effects of zinc and cadmium on LDL-C in Huayuan area. The relationship between metal exposure and blood lipid were not identical against different exposure profiles.

Enhanced Zinc Intake Protects against Oxidative Stress and Its Consequences in the Brain: A Study in an In Vivo Rat Model of Cadmium Exposure

We examined, in a rat model of moderate environmental human exposure to cadmium (Cd), whether the enhanced intake of zinc (Zn) may protect against Cd-caused destroying the oxidative/antioxidative balance and its consequences in the brain. The intoxication with Cd (5 mg/L, 6 months) weakened the enzymatic (superoxide dismutase, glutathione peroxidase, catalase) and non-enzymatic (total thiol groups, reduced glutathione) antioxidative barrier decreasing the total antioxidative status and increased the concentrations of pro-oxidants (hydrogen peroxide, myeloperoxidase) in this organ and its total oxidative status. These resulted in the development of oxidative stress and oxidative modifications of lipids and proteins. The co-administration of Zn (30 and 60 mg/L enhancing this element intake by 79% and 151%, respectively) importantly protected against Cd accumulation in the brain tissue and this xenobiotic-induced development of oxidative stress and oxidative damage to lipids and proteins. Moreover, this bioelement also prevented Cd-mediated oxidative stress evaluated in the serum. The favorable effect of Zn was caused by its independent action and interaction with Cd. Concluding, the enhancement of Zn intake under oral exposure to Cd may prevent the oxidative/antioxidative imbalance and oxidative stress in the brain and thus protect against injury of cellular macromolecules in the nervous system.

Effect of Prepubertal Exposure to CdCl2 on the Liver, Hematological, and Biochemical Parameters in Female Rats; an Experimental Study

The examination chemical factors including industrial toxins and heavy metals seem to be crucial during the prepubertal period. In order to investigate the effects of prepubertal exposure to toxic doses of Cd on liver, hematological, and biochemical parameters in the serum, 16 female rats weaned on postnatal day (PND) 21 were randomly divided into four groups with four rats in each (n = 4). The treatments were as follows: control (0.5 mL distilled water), 25, 50, and 75 mg/kg/day received cadmium chloride (CdCl2). The CdCl2 were administered orally from PND 21 days until observed first vaginal opening (VO). The result showed that the treatment of 75 mg/kg CdCl2 dramatically increased the serum level of LDL (P < 0.0001) and LDL/HDL ratio (P = 0.0004). Conversely, treatment of 75 mg/kg CdCl2 considerably decreased the serum level of HDL in comparison with control group (P = 0.0002). Nevertheless, the rats that received different doses of CdCl2 showed no significant differences in Glu, TG, and TC compared to control group. Number of RBC and Hb of rats treated with 75 mg/kg CdCl2 were significantly less than the other groups (P < 0.0001), whereas a number of WBCs in rats treated with 75 mg/kg CdCl2 (5.27 ± 0.13 10³/μL) showed significant difference (P < 0.0001) compared to control group (4.23 ± 0.09 10³/μL). Histopathological exams showed nodular accumulation of lymphocytes in the liver (lymphocytic hepatitis) of rats, treated with 75 mg/kg CdCl2. These results showed that CdCl2 could cause change in serum lipidome and hematological parameters. What is more, exposure to Cd triggers liver injury and cardiovascular disease during the prepubertal period.

Association of urinary cadmium, circulating fatty acids, and risk of gestational diabetes mellitus: A nested case-control study in China

BACKGROUND

Previous studies have observed that cadmium (Cd) exposure of pregnant women was associated with increased risk of gestational diabetes mellitus (GDM). However, the potential mechanism still remains unclear. In addition, various animal studies have suggested that Cd exposure could affect fatty acids (FAs) metabolism, but data on humans are scant.

OBJECTIVES

We conducted a nested case-control study to investigate the associations of urinary Cd concentrations with levels of circulating FAs and risk of GDM in pregnant women, and further to examine the role of FAs in mediating the relationship between Cd exposure and risk of GDM.

METHODS

A total of 305 GDM cases were matched to 305 controls on pregnant women's age (±2 years) and infant's gender from a birth cohort study conducted in Wuhan, China. Urinary Cd concentrations and levels of plasma FAs between 10 and 16 gestational weeks were measured using inductively coupled plasma mass spectrometry and gas chromatography-mass spectrometry, respectively. Conditional logistic regressions models were used to estimate the associations of Cd concentrations and levels of FAs with the risk of GDM. Multiple linear regression models were applied to estimate the associations between Cd concentrations and levels of FAs. Mediation analysis was used to assess the mediating role of FAs in the association of Cd with the risk of GDM.

RESULTS

Urinary concentrations of Cd in cases (median: 0.69 μg/L) were significantly higher than controls (median: 0.59 μg/L, P < 0.05). Cd concentrations were positively associated with the risk of GDM (P_trend = 0.003). Compared to the first tertile of Cd, the adjusted odds ratios (95% confidence intervals) of GDM risk were 2.08 (1.29, 3.36) for the second tertile and 2.09 (1.32, 3.33) for the third tertile. Cd concentrations were positively correlated with levels of eicosadienoic acid and arachidonic acid/eicosapentaenoic acid ratio, but negatively correlated with levels of stearic acid, eicosapentaenoic acid, total odd-chain saturated fatty acids, total n-3 polyunsaturated fatty acids (PUFAs), and n-3 PUFAs/n-6 PUFAs ratio. We did not observe evidence that the association of Cd exposure and risk of GDM was mediated through FAs.

CONCLUSIONS

Our findings confirmed the association of higher Cd exposure with increased risk of GDM in pregnant women, and provided forceful epidemiological evidence for the relation of Cd concentrations and levels of FAs.

Gut microbiota and lipid metabolism alterations in mice induced by oral cadmium telluride quantum dots

The potential toxicity of cadmium-containing quantum dots (QDs) has received much attention because of increasing biomedical applications. However, little has been known about how cadmium telluride (CdTe) QDs influence the gut microbiota and lipid metabolism. In this study, mice were exposed orally to CdTe QDs (200 μL of 0.2, 2, 20 or 200 μm; twice per week) for 4 weeks. The oral experiments showed CdTe QD exposure led to a decrease of the Firmicutes/Bacteroidetes (F/B) ratio of gut microbiota, which highly negatively correlated with the low-density lipoprotein (LDL), triglyceride (TG) and total cholesterol (TC) levels in serum. In addition, the low-dose (0.2 and 2 μm) CdTe QDs significantly increased the diversity of gut microbiota, and did not elevate the LDL, TG and TC levels in serum. The medium dose (20 μm) of CdTe QDs caused the biggest decrease of the F/B ratio, so it significantly increased the LDL, TG and TC levels compared with the control. Furthermore, high-dose (200 μm) CdTe QDs caused various toxicities in the histopathology of liver and intestine, liver function and intestinal immunity, but did not significantly lead to changes of the LDL, TG and TC levels in serum. This study demonstrates that high-dose oral CdTe QDs mainly lead to tissue damage of the liver and intestine, while the medium and low doses of oral CdTe QDs induce shifts of gut microbiota structure, which are associated with blood lipid levels.

Chronic cadmium exposure and cardiovascular disease in adults

Chronic cadmium exposure and its effect on cardiovascular-related markers were explored in the cross-sectional study of U.S. adults using the National Health and Nutrition Examination Survey (NHANES) 2007-2010 data. Cardiovascular-related markers, such as LDL cholesterol mg/dL (LDL-C), non-HDL cholesterol mg/dL (non-HDL-C), triglycerides mg/dL (TG), c-reactive protein mg/dL (CRP), and gamma-glutamyl transferase U/L (GGT) were explored in relation to urine cadmium level µg/L (UCL). The variables and their relation to UCL µg/L were explored both as continuous and categorical variables using linear and logistic regression models and basic descriptive statistics. Geometric Mean values of the markers of interest were statistically significantly more elevated in middle-aged adults (45-65 years) as compared to younger adults (18-44 years). In linear regression analysis, CRP mg/dL, LDL-C mg/dL, non-HDL-C mg/dL, and GGT U/L levels were significantly associated with UCLs mg/dL after adjusting for confounding variables. In binary logistic regression models, young and middle-aged adults chronically exposed to cadmium were significantly more likely to have elevated CRP mg/dL levels. This study suggests that chronic exposure to cadmium alters cardiovascular-related markers in middle-aged adults more so than younger adults, which calls for early public health intervention to limit cadmium exposure in the U.S.

Effect of cadmium on essential metals and their impact on lipid metabolism in Saccharomyces cerevisiae

Cadmium (Cd) is a toxic heavy metal that induces irregularity in numerous lipid metabolic pathways. Saccharomyces cerevisiae, a model to study lipid metabolism, has been used to establish the molecular basis of cellular responses to Cd toxicity in relation to essential minerals and lipid homeostasis. Multiple pathways sense these environmental stresses and trigger the mineral imbalances specifically calcium (Ca) and zinc (Zn). This review is aimed to elucidate the role of Cd toxicity in yeast, in three different perspectives: (1) elucidate stress response and its adaptation to Cd, (2) understand the physiological role of a macromolecule such as lipids, and (3) study the stress rescue mechanism. Here, we explored the impact of Cd interference on the essential minerals such as Zn and Ca and their influence on endoplasmic reticulum stress and lipid metabolism. Cd toxicity contributes to lipid droplet synthesis by activating OLE1 that is essential to alleviate lipotoxicity. In this review, we expanded our current findings about the effect of Cd on lipid metabolism of budding yeast.

Impact of maternal low-level cadmium exposure on glucose and lipid metabolism of the litter at different ages after weaning

Cadmium (Cd) is a metal which may participate in the development of type II diabetes even if Cd exposure levels are mild. However, experimental studies focusing on daily environmentally relevant doses are scarce, particularly for glucose metabolism of the offspring of chronically exposed mothers. The aim is to measure the impact of maternal low level Cd exposure on glucose and lipid metabolism of offspring. Female rats were exposed to 0, 50 or 500 μg.kg^-1.d^-1 of CdCl₂, 21 days before mating and during 21 days of gestation and 21 days of lactation. Pups exposure was organized in 3 groups (control, Cd1, Cd2) according to renal dams' Cd burden. Parameters of glucose and lipid metabolisms were measured for the pups on post-natal day 21, 26 and 60. Maternal Cd exposure led to significant amounts of Cd in the liver and kidney of pups. At weaning, insulin secretion upon glucose stimulation was unchanged, but the removal of circulating glucose was slower for pups born from the lowest impregnated dams (Cd1). Five days after, glucose tolerance of all groups was identical. Thus, this loss of insulin sensitivity was reversed, in part by increased adiponectin secretion for the Cd1 group. Furthermore, pups from dams accumulating the highest levels of Cd (Cd2) exhibited a compensatory increased insulin pancreatic secretion, together with increased circulating non-esterified fatty acids, indicating the establishment of insulin resistance, 2 months after birth. This study has demonstrated the influence of maternal exposure to low levels of Cd on glucose homeostasis in the offspring that might increase the risk of developing type II diabetes later in life.

Selenium and zinc protections against metal-(loids)-induced toxicity and disease manifestations: A review

Metals are ubiquitous in the environment due to huge industrial applications in the form of different chemicals and from extensive mining activities. The frequent exposures to metals and metalloids are crucial for the human health. Trace metals are beneficial for health whereas non-essential metals are dangerous for the health and some are proven etiological factors for diseases including cancers and neurological disorders. The interactions of essential trace metals such as selenium (Se) and zinc (Zn) with non-essential metals viz. lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in biological system are very critical and complex. A huge number of studies report the protective role of Se and Zn against metal toxicity, both in animal and cellular levels, and also explain the numerous mechanisms involved. However, it has been considered that a tiny dyshomeostasis in the metals/trace metals status in biological system could induce severe deleterious effects that can manifest to numerous diseases. Thus, in this particular review, we have demonstrated the critical protection mechanism/s of Se and Zn against Cd, Pb, As and Hg toxicity in a one by one manner to clarify the up-to-date findings and perspectives. Furthermore, biomolecular consequences are comprehensively presented in light of particular cellular/biomolecular events which are somehow linked to a subsequent disease. The analyzed reports support significant protection potential of Se and Zn, either alone or in combination with other agents, against each of the abovementioned non-essential metals. However, Se and Zn are still not being used as detoxifying agents due to some unexplained reasons. We hypothesized that Se could be a potential candidate for detoxifying As and Hg regardless of their chemical speciations, but requires intensive clinical trials. However, particularly Zn-Hg interaction warrants more investigations both in animal and cellular level.

Urinary cadmium concentration and the risk of ischemic stroke

OBJECTIVES

To examine the association between urinary cadmium levels and the incidence of ischemic stroke and to explore possible effect modifications.

METHODS

A case-cohort study was designed nested in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, including 680 adjudicated incident cases of ischemic stroke and 2,540 participants in a randomly selected subcohort. Urinary creatinine-corrected cadmium concentration was measured at baseline. Multivariable-adjusted hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were estimated with the Barlow weighting method for the Cox proportional hazards regression model.

RESULTS

The median urinary cadmium concentration was 0.42 (interquartile range 0.27-0.68) μg/g creatinine. After adjustment for potential confounders, urinary cadmium was associated with increased incidence of ischemic stroke (quintile 5 vs quintile 1: HR 1.50, 95% CI 1.01-2.22, p for trend = 0.02). The observed association was more pronounced among participants in the lowest serum zinc tertile (tertile 3 vs tertile 1: HR 1.82, 95% CI 1.06-3.11, p for trend = 0.004, p for interaction = 0.05) but was attenuated and became nonsignificant among never smokers (tertile 3 vs tertile 1: never smokers: HR 1.27, 95% CI 0.80-2.03, p for trend = 0.29; ever smokers: HR 1.60, 95% CI 1.06-2.43, p for trend = 0.07, p for interaction = 0.51).

CONCLUSIONS

Findings from this study suggest that cadmium exposure may be an independent risk factor for ischemic stroke in the US general population. Never smoking and maintaining a high serum zinc level may ameliorate the potential adverse effects of cadmium exposure.

The effect of zinc and vitamin E cosupplementation on metabolic status and its related gene expression in patients with gestational diabetes

Objective: The aim of this study was to determine the effects of zinc and vitamin E cosupplementation on metabolic status and gene expression related to insulin and lipid metabolism in women with gestational diabetes mellitus (GDM).Methods: Fifty-four women, in the age range of 18-40 years, diagnosed with GDM were recruited for this randomized, double-blinded, placebo-controlled trial. Subjects were randomly allocated into two intervention groups to either taking 233 mg/day Zinc Gluconate plus 400-IU/day vitamin E supplements or placebo (n = 27 each group) for 6 weeks. Gene expression related to insulin and lipid metabolism was evaluated in peripheral blood mononuclear cells (PBMCs) of women with GDM using RT-PCR method.Results: Participants who received zinc plus vitamin E supplements had significantly lower serum insulin levels (β = -3.81; 95% CI, -5.90, -1.72; p = .001), homeostasis model of assessment-insulin resistance (β = -0.96; 95% CI, -1.54, -0.38; p = .002), serum total-cholesterol (β = -8.56; 95% CI, -16.69, -0.43; p = .03) and low density lipoprotein-cholesterol (LDL)-cholesterol (β = -8.72; 95% CI, -15.27, -2.16; p = .01), and higher quantitative insulin sensitivity check index (β = 0.01; 95% CI, 0.005, 0.02; p = .007) compared with the placebo. Moreover, zinc and vitamin E cosupplementation upregulated gene expression of peroxisome proliferator-activated receptor gamma (PPAR-γ; p = .03) and low-density lipoprotein receptor (LDLR; p = .04) compared with the placebo. Though, zinc and vitamin E combination did not affect other metabolic parameters.Conclusions: Overall, zinc and vitamin E cosupplementation for 6 weeks in women with GDM significantly improved insulin metabolism, lipid profile, and the gene expression levels of PPAR-γ and LDLR.

Cadmium and atherosclerosis: A review of toxicological mechanisms and a meta-analysis of epidemiologic studies

Cadmium has been proposed to be the one of the factors of atherosclerosis development, although the existing data are still controversial. The primary objective of the present study is the review and the meta-analysis of studies demonstrating the association between Cd exposure and atherosclerosis as well as review of the potential mechanisms of such association. We performed a systematic search in the PubMed-Medline database using the MeSH terms cadmium, cardiovascular disease, atherosclerosis, coronary artery disease, myocardial infarction, stroke, mortality and humans up through December 20, 2017. Elevated urinary Cd levels were associated with increased mortality for cardiovascular disease (HR = 1.34, 95% CI: 1.07-1.67) as well as elevated blood Cd levels (HR = 1.78, 95% CI: 1.24-2.56). Analysis restricted to never smokers showed similar, though more imprecise, results. Consistently, we also observed an association between Cd exposure markers (blood and urine) and coronary heart disease, stroke, and peripheral artery disease. Moreover, Cd exposure was associated with atherogenic changes in lipid profile. High Cd exposure was associated with higher TC levels (OR = 1.48, 95% CI: 1.10-2.01), higher LDL-C levels (OR = 1.31, 95% CI 0.99-1.73) and lower HDL-C levels (OR = 1.96, 95% CI: 1.09-3.55). The mechanisms of atherogenic effect of cadmium may involve oxidative stress, inflammation, endothelial dysfunction, enhanced lipid synthesis, up-regulation of adhesion molecules, prostanoid dysbalance, as well as altered glycosaminoglycan synthesis.

Cadmium Alters the Concentration of Fatty Acids in THP-1 Macrophages

Fatty acid composition of human immune cells influences their function. The aim of this study was to evaluate the effects of known toxicant and immunomodulator, cadmium, at low concentrations on levels of selected fatty acids (FAs) in THP-1 macrophages. The differentiation of THP-1 monocytes into macrophages was achieved by administration of phorbol myristate acetate. Macrophages were incubated with various cadmium chloride (CdCl₂) solutions for 48 h at final concentrations of 5 nM, 20 nM, 200 nM, and 2 μM CdCl₂. Fatty acids were extracted from samples according to the Folch method. The fatty acid levels were determined using gas chromatography. The following fatty acids were analyzed: long-chain saturated fatty acids (SFAs) palmitic acid and stearic acid, very long-chain saturated fatty acid (VLSFA) arachidic acid, monounsaturated fatty acids (MUFAs) palmitoleic acid, oleic acid and vaccenic acid, and n-6 polyunsaturated fatty acids (PUFAs) linoleic acid and arachidonic acid. Treatment of macrophages with very low concentrations of cadmium (5-200 nM) resulted in significant reduction in the levels of arachidic, palmitoleic, oleic, vaccenic, and linoleic acids and significant increase in arachidonic acid levels (following exposure to 5 nM Cd), without significant reduction of palmitic and stearic acid levels. Treatment of macrophages with the highest tested cadmium concentration (2 μM) produced significant reduction in the levels of all examined FAs: SFAs, VLSFA, MUFAs, and PUFAs. In conclusion, cadmium at tested concentrations caused significant alterations in THP-1 macrophage fatty acid levels, disrupting their composition, which might dysregulate fatty acid/lipid metabolism thus affecting macrophage behavior and inflammatory state.

The effect of divalent metal chelators and cadmium on serum phosphotriesterase, lactonase and arylesterase activities of paraoxonase 1

Paraoxonase 1 (PON1) is calcium dependent enzyme involved in many functions in human body. PON1 is synthesized in the liver and secreted to the bloodstream where bounds high-density lipoproteins (HDL). Association of PON1 with HDL increases the enzyme stability and biological activities. PON1 have three different activities: phosphotriesterase, lactonase and arylesterase. Until now there is now commercial available kits to determine these three PON1 activities. Also there is no date about stability of PON1 in serum after storage condition. We have elaborated the optimal conditions for determination of PON1 activities in serum using manual procedure as well as the best storage temperature of human serum for determination of PON1 activities. We have also confirmed that PON1 in serum is associated with HDL. Additionally we have investigated the effect of D-penicillamine, ethylenediaminetetraacetic acid and cadmium chloride on PON1 activities in human serum. D-penicillamine and ethylenediaminetetraacetic acid in therapeutic doses as well as cadmium chloride in toxic doses decrease PON1 activities in human serum when compared to non-treated serum. D-penicillamine as metal chelator inhibits much stronger PON1 activities than ethylenediaminetetraacetic acid.

Magnesium-zinc-calcium-vitamin D co-supplementation improves glycemic control and markers of cardiometabolic risk in gestational diabetes: a randomized, double-blind, placebo-controlled trial

To the best our knowledge, data on the effects of magnesium-zinc-calcium-vitamin D co-supplementation on glycemic control and markers of cardiometabolic risk in gestational diabetes mellitus (GDM) are scarce. The purpose of this study was to establish the effects of magnesium-zinc-calcium-vitamin D co-supplementation on glycemic control and markers of cardiometabolic risk of GDM patients. Sixty patients with GDM, aged 18-40 years, were randomized into 2 groups to intake either magnesium-zinc-calcium-vitamin D co-supplements or placebo (n = 30 each group) for 6 weeks in a randomized, double-blind, placebo-controlled trial. Fasting blood samples were taken at baseline and week 6 to quantify related markers. After the 6-week intervention, compared with the placebo, magnesium-zinc-calcium-vitamin D co-supplementation resulted in significant reductions in fasting plasma glucose (-0.37 ± 0.09 vs. +0.01 ± 0.09 mmol/L, P = 0.003), serum insulin levels (-21.0 ± 4.8 vs. +7.2 ± 4.8 pmol/L, P < 0.001), homeostatic model of assessment for insulin resistance (-1.0 ± 1.1 vs. +0.3 ± 1.3, P < 0.001), and a significant increase in quantitative insulin sensitivity check index (+0.02 ± 0.03 vs. -0.002 ± 0.03, P = 0.003). In addition, magnesium-zinc-calcium-vitamin D co-supplementation significantly decreased serum triglycerides (-0.25 ± 0.10 vs. +0.34 ± 0.10 mmol/L, P = 0.001) and very-low-density-cholesterol concentrations (-0.11 ± 0.04 vs. +0.15 ± 0.04 mmol/L, P = 0.001) compared with the placebo. Overall, the results of this study demonstrated that magnesium-zinc-calcium-vitamin D co-supplementation for 6 weeks among patients with GDM had beneficial effects on glycemic control and few markers of cardiometabolic risk.

Effect of Zinc Supplementation on Maintenance Hemodialysis Patients: A Systematic Review and Meta-Analysis of 15 Randomized Controlled Trials

We aimed to examine the effects of zinc supplementation on nutritional status, lipid profile, and antioxidant and anti-inflammatory therapies in maintenance hemodialysis (MHD) patients. We performed a systematic review and meta-analysis of randomized, controlled clinical trials of zinc supplementation. Metaregression analyses were utilized to determine the cause of discrepancy. Begg and Egger tests were performed to assess publication bias. Subgroup analysis was utilized to investigate the effects of zinc supplementation in certain conditions. In the crude pooled results, we found that zinc supplementation resulted in higher serum zinc levels (weighted mean difference [WMD] = 28.489; P < 0.001), higher dietary protein intake (WMD = 8.012; P < 0.001), higher superoxide dismutase levels (WMD = 357.568; P = 0.001), and lower levels of C-reactive protein (WMD = −8.618; P = 0.015) and malondialdehyde (WMD = −1.275; P < 0.001). The results showed no differences in lipid profile. In the metaregression analysis, we found that serum zinc levels correlated positively with intervention time (β = 0.272; P = 0.042) and varied greatly by ethnicity (P = 0.023). Results from Begg and Egger tests showed that there was no significant bias in our meta-analysis (P > 0.1). Results of subgroup analysis supported the above results. Our analysis shows that zinc supplementation may benefit the nutritional status of MHD patients and show a time-effect relationship.

Effect of an Extract from Aronia melanocarpa L. Berries on the Body Status of Zinc and Copper under Chronic Exposure to Cadmium: An In Vivo Experimental Study

In an experimental model of low-level and moderate environmental human exposure to cadmium (Cd), it was investigated whether the consumption of a polyphenol-rich Aronia melanocarpa L. berries (chokeberries) extract (AE) may influence the body status of zinc (Zn) and copper (Cu). The bioelements' apparent absorption, body retention, serum and tissue concentrations, total pool in internal organs, excretion, and the degree of binding to metallothionein were evaluated in female rats administered 0.1% aqueous AE or/and Cd in their diet (1 and 5 mg/kg) for 3-24 months. The consumption of AE alone had no influence on the body status of Zn and Cu. The extract administration at both levels of Cd treatment significantly (completely or partially) protected against most of the changes in the metabolism of Zn and Cu caused by this xenobiotic; however, it increased or decreased some of the Cd-unchanged indices of their body status. Based on the findings, it seems that rational amounts of chokeberry products may be included in the daily diet without the risk of destroying Zn and Cu metabolisms; however, their potential prophylactic use under exposure to Cd needs further study to exclude any unfavourable impact of these essential elements on the metabolism.

Effects of Nano-zinc on Biochemical Parameters in Cadmium-Exposed Rats

Cadmium (Cd) is a toxic environmental and occupational pollutant with reported toxic effects on the kidneys, liver, lungs, bones, and the immunity system. Based on its physicochemical similarity to cadmium, zinc (Zn) shows protective effects against cadmium toxicity and cadmium accumulation in the body. Nano-zinc and nano-zinc oxide (ZnO), recently used in foods and pharmaceutical products, can release a great amount of Zn²⁺ in their environment. This research was carried out to investigate the more potent properties of the metal zinc among sub-acute cadmium intoxicated rats. Seventy-five male Wistar rats were caged in 15 groups. Cadmium chloride (CdCl₂) was used in drinking water to induce cadmium toxicity. Different sizes (15, 20, and 30 nm) and doses of nano-zinc particles (3, 10, 100 mg/kg body weight [bw]) were administered solely and simultaneously with CdCl₂ (2-5 mg/kg bw) for 28 days. The experimental animals were decapitated, and the biochemical biomarkers (enzymatic and non-enzymatic) were determined in their serum after oral exposure to nano-zinc and cadmium. Statistical analysis was carried out with a one-way ANOVA and t test. P < 0.05 was considered as statistically significant. The haematocrit (HCT) significantly increased and blood coagulation time significantly reduced in the nano-zinc-treated rats. AST, ALT, triglyceride, total cholesterol, LDL, and free fatty acids increased significantly in the cadmium- and nano-zinc-treated rats compared with the controls. However, albumin, total protein, and HDLc significantly decreased in the cadmium- and nano-zinc-treated rats compared with the controls (P < 0.05). It seems that in the oral administration of nano-zinc, the smaller sizes with low doses and the larger sizes with high doses are more toxic than metallic zinc. In a few cases, an inverse dose-dependent relationship was seen as well. This research showed that in spite of larger sizes of zinc, smaller sizes of nano-zinc particles are not suitable for protection against cadmium intoxication.

Can zinc supplementation ameliorate cadmium-induced alterations in the bioelement content in rabbits?

The study was designed to investigate the influence of zinc (Zn) supplementation on cadmium-induced alterations in zinc, copper (Cu), and magnesium (Mg) status in rabbits. For this purpose, the concentrations of cadmium (Cd), Zn, Cu, and Mg were estimated in the blood, liver, kidney, and bone. The rabbits were divided in a control group, a Cd group-animals intoxicated orally with Cd (10 mg kg-1 bw, as aqueous solution of Cd-chloride), and a Cd+Zn group-animals intoxicated with the same dose of Cd and co-treated with Zn (20 mg kg-1 bw, as aqueous solution of Zn-sulphate). Solutions were administered orally, every day for 28 days. Sample mineralisation was performed with concentrated nitric acid (HNO3) and perchloric acid (HClO4) (4:1) and metal concentrations were determined by atomic absorption spectrophotometry (AAS). Zinc supplementation improved some of Cd-induced disturbances in bioelement levels in the investigated tissues. Beneficial effects of Zn on Zn and Cu levels were observed in blood, as well as on the Cu kidney level. The calculated values for Cu/Zn, Mg/Zn, and Mg/Cu ratios in blood suggest that Zn co-treatment reduces Cd-induced changes in bioelement ratios in blood.

Evidence of Zinc in Affording Protection Against X-Ray-Induced Brain Injury in Rats

In the present world, X-rays have been regarded as one of the most efficient tools in medicine, industry and research. On the contrary, extensive human exposure to these rays is responsible for causing detrimental effects on physiological system. The aim of the present study was to investigate the role of zinc (Zn), if any, in mitigating the adverse effects induced by fractionated X-irradiation on rat brain. Female Sprague-Dawley rats weighing 170-200 g were divided into four different groups viz.: (a) normal control, (b) X-irradiated (21Gy), (c) zinc treated (227 mg/L in drinking water) and (d) X-irradiated + zinc treated. The skulls of animals belonging to groups (b) and (d) were exposed to X-rays in 30 fractions. Each fraction delivered a radiation dose of 70 rads, and rats were exposed to two fractions every day for 15 days, consecutively. X-ray treatment resulted in significant alterations in the neurobehavior, neurotransmitter levels and neuro-histoarchitecture of rats, whereas zinc co-treatment with X-rays resulted in significant improvement in these parameters. X-ray exposure also caused a significant increase in the levels of lipid peroxidation as well as activities of catalase and superoxide dismutase, which however were decreased upon simultaneous Zn treatment. On the contrary, X-ray treatment down-regulated the glutathione system, which were found to be up-regulated by zinc co-treatment. Further, protein expressions of p53 and NF-ҚB were found to be significantly elevated after X-irradiation, which were reversed following Zn supplementation. Hence, Zn seems to be an effective agent in mitigating the detrimental effects caused by exposure to X-rays.

Cadmium Exposure Is Associated with Monocyte Count and Monocyte to HDL Ratio, a Marker of Inflammation and Future Cardiovascular Disease in the Male Population

Cadmium is a heavy metal that humans can be exposed to the in environment and occupation, and its relationship with cardiovascular diseases has been reported. in various reports. Epidemiological studies have also been associated with various inflammatory markers of cardiovascular diseases. In this study, we examined the relationship between monocyte count and monocyte to high density lipoprotein (HDL) ratio (MHR) and blood cadmium, which are one of the inflammatory markers of cardiovascular diseases. Data from a total of 733 male fire officers who received a health checkup at a hospital for one year in 2016 were analyzed. Populations were classified into 4 groups according to the quartile of blood cadmium and general characteristics were described. The relationship between monocyte count, MHR and cadmium in blood was statistically analyzed by linear regression analysis. In the univariate analysis and multivariate analysis, monocyte count was significantly higher in the second, third and fourth quartile groups than in the first quartile of cadmium, and the linear trend was significant. In univariate and multivariate analysis, MHR was significantly higher in the third and fourth quartile groups than in the first quartile group, and the linear trend was also significant. This study showed the significant relationship between blood cadmium and monocyte count and MHR among male fire officers. This was also statistically significant in the model adjusted for possible confounders and other cardiovascular risk factors and showed a linear trend.

Dyslipdemia induced by chronic low dose co-exposure to lead, cadmium and manganese in rats: the role of oxidative stress

Lead (Pb), cadmium (Cd) and manganese (Mn) have many potential adverse health effects in vitro and in animal models of clinical toxicity. The current study investigated the dyslipidaemic and oxidative stress effects of chronic low-dose oral exposure to Pb, Cd and Mn and the combination (Pb+Cd+Mn) in rats for 15 weeks. Chronic exposure to the metals did not significantly (P>0.05) alter serum lipid profiles. However, the atherogenic index decreased by 32.2% in the Pb+Cd+Mn group, relative to the control. The triglyceride/high-density lipoprotein cholesterol ratio decreased by 39.4% in the Pb+Cd+Mn group, relative to the control, and elevated by 81.8, 94.8 and 20.8%, relative to the Pb, Cd and Mn groups, respectively. While the serum concentrations of malondialdehyde significantly increased in the Mn and Pb+Cd+Mn groups, that of glutathione peroxidase-1 decreased in the Pb+Cd+Mn group, and metallothionein-1 and zinc concentrations markedly decreased in all the metal treatment groups. The results suggest that long-term exposure of rats to Pb+Cd+Mn may result in hypolipidaemia, mediated via oxidative stress and metal interactions. Individuals who are constantly exposed to environmentally relevant levels of the metals may be at risk of hypolipidaemia.

Effects of Subcutaneous Injection MnO2 Micro- and Nanoparticles on Blood Glucose Level and Lipid Profile in Rat

BACKGROUND

The use of nanotechnology has led to rapid growth in various areas. Thus, health and safety issues of nanoparticles (NPs) should be promptly addressed. Manganese oxide (MnO₂) nanoparticles (NPs) are typically used for biomedical and industrial applications. However, characterizing the potential human health effects of MnO₂ NPs is required before fully exploiting these materials. The aim of this study was to investigate the toxicity of MnO₂ micro- and nanoparticles on blood glucose level and lipid profile in male Wistar rats.

METHODS

A total of 105 rats were divided into one control and two experimental groups. Each experimental group received a single subcutaneous injection of MnO₂ micro- and nanoparticles (100 μg/kg), respectively, every two weeks for 14 weeks. Their blood glucose, cholesterol, triglycerides, LDL, and HDL levels were then measured. The data presented as mean±SEM and compared with the repeated measures using the Prism statistical software (version 6.0).

RESULTS

Biochemical assessment in plasma samples showed that MnO₂ micro- and nanoparticles injection significantly (P<0.01) increased the plasma glucose and cholesterol levels in all and few weeks, respectively. MnO₂ nanoparticles significantly (P<0.01) decreased the HDL level in weeks 6, 12, and 14, but MnO₂ microparticles decreased the HDL level only in week 12. In both MnO₂ micro- and nanoparticles groups, LDL alterations were near to the control group, except for week 10. However, the same treatment had no effect on triglycerides concentrations compared to the control group.

CONCLUSION

Our results show that exposure to nanosized particles at subchronic doses caused adverse changes in animal biochemical profiles, especially in glucose level. It seems that the high oxidative power of these particles is the main reason for these disturbances.