New Evidence against Chromium as an Essential Trace Element

Comparative assessment of chromate bioremediation potential of Pantoea conspicua and Aspergillus niger

The recent work aims at the use of Pantoea conspicua (MT5) and Aspergillus niger (CRS3) to assess their bioremediation potential and growth restoration of Helianthus annuus L. under chromate (Cr⁺⁶) stress. The growth of the P. conspicua and A. niger was tested in Cr⁺⁶ supplemented media. The strains can withstand up to 1200 and 900 ppm respectively in the media and effectively bio-transform it to nontoxic form. Supplemented metal's levels significantly decreased the growth attribute of H. annuus (p< 0.05). On the other hand, P. conspicua and A. niger rescued the host plant by establishing higher colonization frequency with the host roots. Moreover, MT5 bio-transformed the toxic Cr⁺⁶ to non-toxic Cr⁺³ form in the rhizosphere. It also enhanced the host plant growth by producing phytohormones and ceasing Cr uptake and accumulation. Contrarily, CRS3 tends to accumulate and bio-transform metal in their hyphae. Nonetheless, both of the microbes tend to modulate phytohormones production and strengthening antioxidant system of the host. Improvement in the antioxidant system enabled the host plant to produce higher phenolics and flavonoids, and lower peroxidase. The associated plant species also exhibited higher ROS scavenging and lower ROS accumulation. Besides, the strains were able to produce higher amounts of phytohormones, including IAA, GA, and SA. Such activities rendered them as excellent phytostimulants, that can be used as biofertilizers in chromium polluted soils.

Development of Solid Phase Extraction Method Based on Ion Imprinted Polymer for Determination of Cr(III) Ions by ETAAS in Waters

In this work, a new solid phase extraction method for the determination of chromium species in water samples by electrothermal atomic absorption spectrometry was developed. For selective separation of Cr(III) ions under dynamic conditions, two ion imprinted polymers containing Cr(III)-1,10-phenanthroline complex (Cr(III)-phen) were prepared with the use of one (styrene, ST) or two (styrene and 4-vinylpyridine, ST-4VP) functional monomers. The physicochemical properties of those solid sorbents towards Cr(III) ions were studied and compared. It was found that Cr(III) ions were retained on the Cr(III)-phen-ST and Cr(III)-phen-ST-4VP polymers with high efficiency and repeatability (91.6% and 92.9%, RSD < 2%) from solutions at pH 4.5. The quantitative recovery of the analyte (91.7% and 93.9%, RSD < 4%) was obtained with 0.1 mol/L EDTA solution. The introduction of 4VP, an additional functional monomer, improved selectivity of the Cr(III)-phen-ST-4VP polymer towards Cr(III) ions in the presence of Cu(II), Mn(II) and Fe(III) ions, and slightly decreased the sorption capacity and stability of that polymer. The accuracy of procedures based on both polymeric sorbents was proved by analyzing the standard reference material of surface water SRM 1643e. The method using the Cr(III)-phen-ST polymer was applied for determining of Cr(III) ions in tap water and infusion of a green tea.

The effect of chromium intake on oxidative stress parameters: A systematic review and meta-analysis

BACKGROUND

Trivalent chromium is a trace element thought to have a beneficial effect on oxidative stress (OS) parameters and inflammation. This review aimed to investigate the dose-response of chromium and summarize the effects of chromium supplementation on OS parameters in the literature.

METHODS

MEDLINE, Scopus, Web of Science and Cochrane CENTRAL databases were searched for RCTs published from inception to January 2021 evaluating the effect of chromium supplementation on OS parameters, namely MDA, TBARS, SOD, TAS, CAT, GPx, and GSH. A random-effects model was used to pool data and calculated standard mean difference and 95 % confidence intervals. Quantified heterogeneity among studies was assessed through Cochrane's I² values.

RESULTS

Nine studies enrolling 550 participants met the inclusion criteria. The obtained results indicate that chromium supplementation significantly increases TAC (SMD: 0.46; 95 % CI: 0.08, 0.84; I² = 00.0 % n = 2) and significantly decreases MDA levels (SMD: -0.46; 95 % CI: -0.86, -0.07; I² = 52.4 % n = 5). Supplementation did not significantly change CAT, GPx, GSH, SOD, TAS, and TBARS.

CONCLUSION

Chromium supplementation may improve OS parameters, however, due to high heterogeneity observed in the included studies, these findings should be interpreted with caution. Large RCTs on various patient groups evaluating the impact of chromium supplementation are needed to allow an adequate generalization of the benefits of chromium on human health.

Urea Gel Electrophoresis in Studies of Conformational Changes of Transferrin on Binding and Transport of Non-Ferric Metal Ions

Transferrin (Tf) is a crucial transporter protein for Fe(III), but its biological role in binding other metal ions and their delivery into cells remain highly controversial. The first systematic exploration of the effect of non-Fe(III) metal ion binding on Tf conformation has been performed by urea-polyacrylamide gel electrophoresis (urea-PAGE), which is commonly used for nucleic acids but rarely for proteins. Closed Tf conformation, similar to that caused by Fe(III)-Tf binding, was formed for In(III), V(III) or Cr(III) binding to Tf. In all these cases, metal distribution between Tf lobes and/or the rate of metal release under acidic conditions differed from that of Fe(III)-Tf. By contrast, Ga(III) and V(IV) did not form closed Tf conformation under urea-PAGE conditions. Apart from Fe(III), only In(III) was able to increase the proportion of closed Tf conformation in whole serum. These results suggest that Tf is unlikely to act as a natural carrier of any metal ion, except Fe(III), into cells but can reduce toxicity of exogenous metal ions by binding them in serum and preventing their entry into cells.

Nutritional therapy can reduce the burden of depression management in low income countries: A review

Depression is a serious mental and mood disorder with global health and economic burden. This burden may be overwhelming in low income countries, although there are insufficient data. Most antidepressant formulations are predicated on the monoamine, neuroendocrine and neuro-inflammation hypotheses, with little or no cognizance to other neurochemicals altered in depression. A nutritional strategy with or without conventional antidepressants is recommended, as nutrition plays vital roles in the onset, severity and duration of depression, with poor nutrition contributing to its pathogenesis. This review discusses nutritional potentials of utilizing omega-3 fatty acids, proteins, vitamins, minerals and herbs or their phytochemicals in the management of depression with the aim of reducing depression burden. Literature search of empirical data in books and journals in data bases including but not limited to PubMed, Scopus, Science Direct, Web of Science and Google Scholar that might contain discussions of sampling were sought, their full text obtained, and searched for relevant content to determine eligibility. Omega-3 fatty and amino acids had significant positive anti-depression outcomes, while vitamins and minerals although essential, enhanced omega-3 fatty and amino acids activities. Some herbs either as whole extracts or their phytochemicals/metabolites had significant positive anti-depression efficacy. Nutrition through the application of necessary food classes or herbs as well as their phytochemicals, may go a long way to effectively manage depression. This therefore will provide inexpensive, natural, and non-invasive therapeutic means with reduced adverse effects that can also be applied alongside clinical management. This nutritional strategy should be given more attention in research, assessment and treatment for those with depression and other mental illness in low income countries, especially in Africa.

Phytohormones Producing Acinetobacter bouvetii P1 Mitigates Chromate Stress in Sunflower by Provoking Host Antioxidant Response

Different physical and chemical techniques are used for the decontamination of Cr+6 contaminated sites. The techniques are expensive, laborious, and time-consuming. However, remediation of Cr+6 by microbes is viable, efficient, and cost-effective. In this context, plant growth-promoting rhizobacteria Acinetobacter bouvetii P1 isolated from the industrial zone was tested for its role in relieving Cr+6 induced oxidative stress in sunflower. At the elevated Cr+6 levels and in the absence of P1, the growth of the sunflower plants was inhibited. In contrast, the selected strain P1 restored the sunflower growth under Cr+6 through plant growth-promoting interactions. Specifically, P1 biotransformed the Cr+6 into a stable and less toxic Cr+3 form, thus avoiding the possibility of phytotoxicity. On the one hand, the P1 strengthened the host antioxidant system by triggering higher production of enzymatic antioxidants, including catalases, ascorbate peroxidase, superoxide dismutase, and peroxidase. Similarly, P1 also promoted higher production of nonenzymatic antioxidants, such as flavonoids, phenolics, proline, and glutathione. Apart from the bioremediation, P1 solubilized phosphate and produced indole acetic acid, gibberellic acid, and salicylic acid. The production of phytohormones not only helped the host plant growth but also mitigated the harsh condition posed by the elevated levels of Cr+6. The findings mentioned above suggest that P1 may serve as an excellent phyto-stimulant and bio-remediator in a heavy metal-contaminated environment.

Effects of exogenous sulfate on the chromium(VI) metabolism of chromium(VI)-resistant engineered strains

OBJECTIVE

To explore the effects of exogenous sulfate on the efficiency of chromium(VI) metabolism of three chromium(VI)-resistant Escherichia coli strains (eChrA / eChrB / eChrAB) by adding chromium(VI)-resistance genes chrA and/or chrB, for better understanding and further application of these Cr(VI)-resistant strains in environmental and industrial chromium removal.

METHODS

Based on three engineered Cr(VI)-resistant strains exposed to different concentrations of sulfate: i) Evaluation of Cr(VI) metabolism characteristics, including the growth rate, the Cr(VI) tolerance, the removal, absorption and efflux capacity of Cr(VI); ii) Detection the expressions of Cr(VI) resistance-related genes (chrA and chrB), and sulfate channel protein-related genes (sbp, cysA, cysU and cysW genes) by RT-qPCR.

RESULTS

Exogenous sulfate enhanced the Cr(VI) tolerance and the removal rate of these three engineered Cr(VI)-resistant strains, and promoted their growth rate under Cr(VI) stress, while suppressed their absorption and efflux capacity. Under a certain sulfate concentration, the Cr(VI) tolerance, removal ability and efflux capacity of these three strains were ranked as follow: eChrAB > eChrA > eChrB, while ranked as eChrB > eChrA > eChrAB for the Cr(VI) absorption rate, respectively. Opposite to the Cr(VI) treatment, exogenous sulfate suppressed the transcription levels of the Cr(VI) resistance-related genes (chrA and chrB) with gradually increased concentrations, and reduced those of sulfate channel protein related genes (sbp,cysA, cysU and cysW) under the medium and high concentrations.

CONCLUSION

Sulfate can enhance the Cr(VI) tolerance and growth of Cr(VI)-resistant strains, via inhibiting the Cr(VI) absorption and efflux in a concentration-dependent manner. The underlying mode of action might be the competition of transport channels between sulfate and Cr(VI), and the suppression of sulfate channel protein related genes expressions by exogenous sulfate. Our results demonstrated an appropriate supplication of exogenous sulfate could contribute to the Cr(VI) pollution management by genes chrA/chrB related Cr(VI)-resistant strains. Additionally, the engineered E. coli strain eChrAB showed more potential for the actual Cr(VI) pollution application than strain eChrA and eChrB.

The Association Between Trace Elements and Osmolality in Plasma and Aqueous Humor Fluid in Diabetic Rabbits

Trace element metabolism plays an important role in the formation of diabetes and complications of diabetes. Although trace elements changes in lenses in diabetic cataract and glaucoma formation have been investigated, there were few studies evaluating trace elements levels in plasma and aqueous humor fluid in diabetic and non-diabetic conditions. Therefore, we aimed to investigate zinc (Zn), copper (Cu), and chromium (Cr) levels in plasma and aqueous humor fluids of rabbits in the diabetic rabbit model. New Zealand male rabbits were divided into two groups as control (n = 8), and diabetes (n = 8) induced by alloxane. At the end of the experimental period, the osmolality in blood, plasma, and aqueous humor fluids from rabbits were measured by osmometer and Zn, Cu, and Cr levels in plasma and aqueous humor fluid were measured by inductively coupled plasma-optical emission spectrophotometer (ICP-OES). The osmolality in blood, plasma, and aqueous humor fluid of the diabetic group was significantly increased compared to the control group (respectively p < 0.01, p < 0.001, p < 0.001). It was analyzed that plasma Zn and Cu levels of diabetic rabbits increased significantly (respectively, p < 0.01; p < 0.001), whereas Cr level significantly decreased according to the control group (p < 0.01). It was observed that Cr and Zn levels in aqueous humor fluid in diabetes group decreased (respectively p < 0.001 and p < 0.01), and a significantly increased in Cu level (p < 0.001) compared to the control group. Related with these changes that may occur in the eye due to the measured parameters, we consider that comparative studies of these types of diabetic animal models would be useful in the evaluation of diabetes and its complications.

Genotoxicity of chromium (III) and cobalt (II) and interactions between them

Introduction. Chromium and cobalt are essential trace elements that are required only in a small amount, otherwise their excess can cause toxic effects.

Aim. The aim of this study was to determine the effects of chromium (III) and cobalt (II) and their combinations on genotoxicity in human fibroblasts cells (BJ).

Material and methods. In this work, comet and micronucleus assays were used. The BJ cells were exposed to chromium chloride and cobalt chloride at concentration ranges from 100 to 1400 µM. Mixtures of these elements were prepared so as to examine interactions between them.

Results. The present study shows the genotoxic effects of chromium (III) and cobalt (II) and their mixtures on BJ cells. In the comet assay, no comets were observed at the lowest concentrations; in the higher, a significant increase in their percentage was observed. In the other assay (formation of micronuclei), a statistically significant increase in the number of cells with micronuclei was observed in the BJ cells spiked with cobalt chloride and chromium chloride. In the case of simultaneous incubation of chromium chloride at 200 µM and cobalt chloride at 1000 µM in the BJ line, antagonism was observed. However, the interaction of chromium chloride at the 1000 µM and cobalt chloride at 200 µM leads to synergism between the studied elements.

Conclusions. Cobalt (II) and chromium (III) show genotoxic properties, they induce breaks in double and single-stranded DNA and they cause formation of AP-sites that do not have purine or pyrimidine bases.

Chromium picolinate balances the metabolic and clinical markers in nonalcoholic fatty liver disease: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) is a complicated disease and is considered as a severe global health problem affecting 30% of adults worldwide. The present study aimed to evaluate changes in oxidative stress, adipokines, liver enzyme, and body composition following treatment with chromium picolinate (CrPic) among patients with NAFLD.

PARTICIPANTS AND METHODS

The current randomized, double-blind, placebo-controlled study was conducted on 46 NAFLD patients with the age range of 20-65 years. Patients were randomly classified into two groups, receiving either 400 µg CrPic tablets in two divided doses of 200 µg (23 patients) or placebo (23 patients) daily for 12 weeks. The participants' body composition and biochemical parameters were evaluated at the baseline and after 12 weeks.

RESULTS

Serum levels of liver enzymes reduced significantly only in the CrPic group (P < 0.05 for all), but not between the groups after the intervention. Besides, there were significant differences between the study groups regarding body weight and body fat mass, total antioxidant capacity, superoxide dismutase, malondialdehyde, leptin, and adiponectin post-intervention (P = 0.017, P = 0.032, P = 0.003, P = 0.023, P = 0.012, P = 0.003, and P = 0.042, respectively). However, glutathione peroxidase and resistin levels did not differ significantly between groups (P = 0.127 and P = 0.688, respectively).

DISCUSSION AND CONCLUSION

This study showed that consuming 400 µg/day of CrPic for 12 weeks in patients with NAFLD causes a significant change in leptin, adiponectin, oxidative stress (expect glutathione peroxidase), and body weight, compared to baseline. Nevertheless, it does not affect liver enzymes. Therefore, the CrPic supplementation may improve adipokines, some anthropometric indices, and oxidative stress in patients with NAFLD.

In Vitro Element Bioavailability Studies of Some Underutilized Seeds in Southeast Nigeria

Elemental and antinutritional compositions of three underutilized seeds (Mucuna sloanei, Brachystegia eurycoma and Detarium microcarpum) were analysed to elucidate their safety and wholesomeness as human food supplements or condiments using standard analytical methods. Results showed that there were significant differences in the concentration levels of the elements and the antinutrient contents of the seeds. The toxic element concentration levels clearly indicated that they exhibited acceptable values when compared with the recommended standards. There existed correlation between the contents of potassium, manganese, selenium and lead of the samples; calcium had inverse relationship with the oxalate contents, while lead and manganese had perfect association in all the samples. The results of elemental ratios showed synergistic interactions with exception of iron to zinc ratio in all the seeds. Element bioavailability in the presence of oxalate and phytate were all in tandem with the standard values. The results further revealed that zinc in all the seeds and selenium in Mucuna sloanei and Brachystegia eurycoma were overloaded in the samples, while the elemental safety index values for the other elements indicated that the seeds were safe. Overall, the findings of this study have strongly confirmed the nutritional potentials of these seeds and its safety and wholesomeness as human food condiments.

Nutrition and Metabolism of Minerals in Fish

Simple Summary

Our aim is to introduce the mineral nutrition of fish and explain the complexity of determining requirements for these elements, which are absorbed and excreted by the fish into the surrounding water. To date, only the requirements for nine minerals have been investigated. The review is focused on the absorption and the dietary factors that reduce their absorption from feed ingredients of plant and animal origin. Some diseases, such as cataracts, anemia and bone deformity, have been linked to dietary deficiency of minerals.

Abstract

Aquatic animals have unique physiological mechanisms to absorb and retain minerals from their diets and water. Research and development in the area of mineral nutrition of farmed fish and crustaceans have been relatively slow and major gaps exist in the knowledge of trace element requirements, physiological functions and bioavailability from feed ingredients. Quantitative dietary requirements have been reported for three macroelements (calcium, phosphorus and magnesium) and six trace minerals (zinc, iron, copper, manganese, iodine and selenium) for selected fish species. Mineral deficiency signs in fish include reduced bone mineralization, anorexia, lens cataracts (zinc), skeletal deformities (phosphorus, magnesium, zinc), fin erosion (copper, zinc), nephrocalcinosis (magnesium deficiency, selenium toxicity), thyroid hyperplasia (iodine), muscular dystrophy (selenium) and hypochromic microcytic anemia (iron). An excessive intake of minerals from either diet or gill uptake causes toxicity and therefore a fine balance between mineral deficiency and toxicity is vital for aquatic organisms to maintain their homeostasis, either through increased absorption or excretion. Release of minerals from uneaten or undigested feed and from urinary excretion can cause eutrophication of natural waters, which requires additional consideration in feed formulation. The current knowledge in mineral nutrition of fish is briefly reviewed.

Impact of Environmental and Lifestyle Use of Chromium on Male Fertility: Focus on Antioxidant Activity and Oxidative Stress

Male reproductive tissues are strongly susceptible to several environmental and lifestyle stressors. In general, male reproductive health is highly sensitive to oxidative stress, which results in reversible and/or irreversible changes in testosterone-producing cells, spermatogenesis, and sperm quality. Chromium compounds are widely used in the +3 and +6 valence states, as food supplements, and in the industrial field, respectively. Chromium (III) compounds, i.e., Cr(III)-tris-picolinate, [Cr(pic)₃], known as chromium picolinate, are used as nutritional supplements for the control of diabetes, body weight, and muscular growth. However, previous studies showed that animal models exposed to chromium picolinate experienced degenerative changes in spermatogenesis. Contradictory results are documented in the literature and deserve discussion. Furthermore, the long-term effects of chromium picolinate on the antioxidant system of treated subjects have not been properly studied. Comprehensive studies on the role of this compound will help to establish the safe and useful use of chromium supplementation. On the other hand, chromium (VI) compounds are widely used in several industries, despite being well-known environmental pollutants (i.e., welding fumes). Chromium (VI) is known for its deleterious effects on male reproductive health as toxic, carcinogenic, and mutagenic. Previous studies have demonstrated severe lesions to mouse spermatogenesis after exposure to chromium (VI). However, workers worldwide are still exposed to hexavalent chromium, particularly in electronics and military industries. Data from the literature pinpoints mechanisms of oxidative stress induced by chromium compounds in somatic and germ cells that lead to apoptosis, thus underlining the impairment of fertility potential. In this review, we analyze the benefits and risks of chromium compounds on male fertility, as well as the mechanisms underlying (in)fertility outcomes. Although supplements with antioxidant properties may maximize male fertility, adverse effects need to be investigated and discussed.

The Impact of Chromium Supplementation on Blood Pressure: A Systematic Review and Dose-Response Meta‑Analysis of Randomized‑Controlled Trials

INTRODUCTION

Potential effects of chromium supplementation on blood pressure (BP) have been examined in several interventional studies. Nevertheless, findings in this context are controversial.

AIM

Therefore, the current systematic review and meta-analysis aimed to comprehensively assess the impact of chromium supplementation on BP.

METHODS

Five online databases including Web of Science, Scopus, Embase, Google Scholar, and PubMed were systematically searched from inception to March 2020. We included all randomized clinical trials (RCTs) evaluating the effects of chromium supplementation on systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) in humans.

RESULTS

The random-effects meta-analysis of 11 eligible RCTs with 637 participants demonstrated the significant decline in both SBP (WMD - 2.51 mmHg; 95% CI - 4.97 to - 0.05, p = 0.04) and DBP (WMD - 1.04 mmHg; 95% CI - 1.96 to - 0.12, p = 0.026) following supplementation with chromium. In subgroup analysis, studies that were administered chromium yeast and brewer's yeast, showed greater decrease in SBP. Also, in stratification based on participants' health status, significant reduction in SBP only was seen in diabetic patients with chronic heart disease (CHD). Nonlinear dose-response analysis revealed a significant influence of chromium dosage on SBP changes.

CONCLUSION

The current meta-analysis, indicated that supplementation with chromium significantly decrease SBP and DBP. In subgroup analysis, administration of chromium yeast and brewer's yeast resulted in greater reduction in SBP. Further large-scale RCTs with better design are needed to confirm these findings.

Effect of trivalent chromium on erythropoietin production and the prevention of insulin resistance in HepG2 cells

In erythropoietin (EPO)-producing HepG2 cells, we investigated the effect of trivalent chromium (Cr) on the promotion of EPO production and the induction of insulin resistance. Cr increased hypoxia-inducible factor (HIF)-1α protein, EPO mRNA expression and EPO protein levels in HepG2 cells. The effect of Cr on EPO production was inhibited by inhibition of proliferator-activated receptor γ (PPARγ). Insulin resistance was induced by culturing with insulin resistance induction medium supplemented with palmitic acid for 24 h. When Cr was added to the medium, the increase in glucose-6-phosphatase and phosphoenolpyruvate carboxykinase 1 mRNA expression levels and the decrease in the ratio of phosphorylated Akt to Akt protein were suppressed, and the induction of insulin resistance prevented. When a PPARγ inhibitor or siPPARγ was added together with Cr, the inhibitory effect of Cr on the induction of insulin resistance disappeared. In addition, pretreatment with siEPO suppressed the increase in EPO mRNA expression, and the inhibitory effect on the induction of insulin resistance due to the addition of Cr was significantly reduced. These results suggest that the inhibition of insulin resistance induction by Cr in HepG2 cells involves the promotion of EPO production mediated by PPARγ, in addition to other PPARγ-mediated activities.

Ni and Cr impurities profile in Valeriana officinalis L., radix-based herbal medicinal product available in polish pharmacies due to ICH Q3D guideline

Elemental impurities (EIs) profiling in final pharmaceutical products is often not adequately treated, however it is crucial problem in pharmaceutical analysis by reason of the various regulatory authorities (like ICH Q3D guideline). EIs in pharmaceuticals may arise from numerous sources of which the herbal ingredients are not a frequent subject of pharmaceutical analyses. However, based on number of traditional use registrations per year for herbal medicinal products (HMPs) in the EU, it can be stated that monocomponent HMPs are still very popular for use. Due to the high frequency of use, exposure to EIs from HMPs may be high during long-term use. The aim of our article was Ni and Cr impurities profiling of Valeriana officinalis L., radix (Valerian root) as an example of the HMP available in Polish pharmacies for the relief of mild nervous tension and sleep disorders. The choice of metals was justified by: (1) a single dose of Ni administered via oral route can induce dermatitis in nickel-sensitised individuals; (2) Cr is a very problematic element from toxicological point of view. Our results indicate that the standards of the ICH Q3D guideline are met for all EIs.

Effects of supplementing different chromium histidinate complexes on glucose and lipid metabolism and related protein expressions in rats fed a high-fat diet

BACKGROUND

The objective of this study was to investigate the effects of different chromium histidinate (CrHis) complexes added to the diet of rats fed a high-fat diet (HFD) on body weight changes, glucose and lipid metabolism parameters, and changes in biomarkers such as PPAR-γ, IRS-1, GLUTs, and NF-κB proteins.

METHODS

Forty-two Sprague-Dawley rats were divided equally into six groups and fed either a control, an HFD, or an HFD supplemented with either CrHis1, CrHis2, CrHis3, or a combination of the CrHis complexes as CrHisM.

RESULTS

Feeding an HFD to rats increased body weights, HOMA-IR values, fasting serum glucose, insulin, leptin, free fatty acid, total cholesterol, low-density lipoprotein cholesterol, and MDA concentrations as well as AST activities, and decreased serum and brain serotonin concentrations compared with rats fed a control diet (P <  0.0001). The levels of the PPAR-γ, IRS-1, and GLUTs in the liver and brain decreased, while NF-κB level increased, with feeding an HFD (P <  0.05). Although all the CrHis supplements reversed the negative effects of feeding an HFD (P <  0.05), the CrHis1 complex was most effective in changing the protein levels, while CrHisM was most effective in influencing certain parameters such as body weight and serum metabolites.

CONCLUSION

The results of the present work suggest that the CrHis1 complex is most potent for alleviating the negative effects of feeding an HFD. The efficacy of CrHisM is likely due to the presence of the CrHis1 complex.

Potential Ameliorative Effects of Chromium Supplementation on Glucose Metabolism, Obesity, and Genomic Stability in Prediabetic Rat Model

Chromium (III) (Cr(III)) effect on improving glucose, body mass loss, and genomic stability has been extensively studied in models of type 2 diabetes. However, there is a lack of studies evaluating its effect on prediabetes. Thus, this study evaluates the effects of Cr(III) as dietetic supplementation on glucose metabolism, obesity, and genomic stability on prediabetic rat model using high-invert sugar. Male Wistar rats were divided randomly into four treatment groups: (1) control, receiving standard diet (control); (2) prediabetic (PD), receiving a 32% of invert sugar; (3) Cr(III), receiving chromium (III) chloride (CrCl₃•6H₂O) (58.4 mg/L); and (4) Cr(III) + PD, receiving CrCl₃•6H₂O in combination with high-invert sugar. Cr(III) supplementation significantly reduced blood glucose (123.00 ± 8.29 mg/dL vs. 115.30 ± 9.31 mg/dL, p = 0.015) and partially reduced area under the 120-min blood glucose response curve (AUC) in PD rats (p = 0.227). Moreover, Cr(III) attenuated weight gain (187.29 ± 38.56 g vs. 167.22 ± 29.30 g, p = 0.004), significantly reducing body mass index (0.68 ± 0.04 g/cm² vs. 0.63 ± 0.04 g/cm², p < 0.001), Lee index (0.30 ± 0.01 vs. 0.28 ± 0.01, p < 0.001), and peritoneal fat (p < 0.001). Regarding genomic stability, high-invert sugar, Cr(III), or the combination of both did not produce changes in oxidative stress, DNA damage in pancreas, or cytotoxicity markers. These data suggest that Cr(III) supplementation improved partially glucose metabolism and reduced obesity in rat model PD due to high-invert sugar without influence in genomic stability.

Toxic Mechanisms of Five Heavy Metals: Mercury, Lead, Chromium, Cadmium, and Arsenic

The industrial activities of the last century have caused massive increases in human exposure to heavy metals. Mercury, lead, chromium, cadmium, and arsenic have been the most common heavy metals that induced human poisonings. Here, we reviewed the mechanistic action of these heavy metals according to the available animal and human studies. Acute or chronic poisonings may occur following exposure through water, air, and food. Bioaccumulation of these heavy metals leads to a diversity of toxic effects on a variety of body tissues and organs. Heavy metals disrupt cellular events including growth, proliferation, differentiation, damage-repairing processes, and apoptosis. Comparison of the mechanisms of action reveals similar pathways for these metals to induce toxicity including ROS generation, weakening of the antioxidant defense, enzyme inactivation, and oxidative stress. On the other hand, some of them have selective binding to specific macromolecules. The interaction of lead with aminolevulinic acid dehydratase and ferrochelatase is within this context. Reactions of other heavy metals with certain proteins were discussed as well. Some toxic metals including chromium, cadmium, and arsenic cause genomic instability. Defects in DNA repair following the induction of oxidative stress and DNA damage by the three metals have been considered as the cause of their carcinogenicity. Even with the current knowledge of hazards of heavy metals, the incidence of poisoning remains considerable and requires preventive and effective treatment. The application of chelation therapy for the management of metal poisoning could be another aspect of heavy metals to be reviewed in the future.

Exposure to metal mixtures in relation to blood pressure among children 5-7 years old: An observational study in Bangladesh

Hypertension in later life, a significant risk factor for cardiovascular disease, has been linked to elevated blood pressure in early life. Exposure to metals may influence childhood blood pressure; however, previous research is limited and has mainly focused on evaluating the toxicity of single metal exposures. This study evaluates the associations between exposure to metal mixtures and blood pressure among Bangladeshi children age 5-7 years.

METHODS

We investigated the associations of 17 toenail metal concentrations with blood pressure using linear regression models. Principal component analysis (PCA), weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) were conducted as secondary analyses.

RESULTS

Associations were observed for selenium with diastolic blood pressure (per doubling of exposure β = 2.91, 95% confidence interval [CI] = 1.08, 4.75), molybdenum with systolic (β = 0.33, 95% CI = 0.05, 0.61) and diastolic blood pressure (β = 0.39, 95% CI = 0.12, 0.66), tin with systolic blood pressure (β = -0.33, 95% CI = -0.60, -0.06), and mercury with systolic (β = -0.83, 95% CI = -1.49, -0.17) and diastolic blood pressure (β = -0.89, 95% CI = -1.53, -0.26). Chromium was associated with diastolic blood pressure among boys only (β = 1.10, 95% CI = 0.28, 1.92, P for interaction = 0.02), and copper was associated with diastolic blood pressure among girls only (β = -1.97, 95% CI = -3.63, -0.32, P for interaction = 0.01). These findings were largely robust to the secondary analyses that utilized mixture modeling approaches (PCA, WQS, and BKMR).

CONCLUSIONS

Future prospective studies are needed to investigate further the impact of early life exposure to metal mixtures on children's blood pressure trajectories and cardiovascular disease risk later in life.

Multi-elemental Analysis, Pattern Recognition Techniques of Wild and Cultivated Rosehips from Serbia, and Nutritional Aspect

Twenty-six major and trace elements, in the seed and the mesocarp of wild and cultivated rosehips from different locations in Serbia, were quantified by means of inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The cultivated rosehip was investigated for the first time. In both wild and cultivated rosehips, the most abundant elements were K and Ca. Among trace elements, Mn (in both seed and mesocarp); Fe (in seeds); and B, Ba, and Sr (in mesocarp) were quantified in the highest concentrations. The higher content of Cu, K, Mn, P, and S in the seed of cultivated rosehip, as well as Ca, Mg, and Sr in the mesocarp of wild rosehip, was observed, both significant at p < 0.05. Additionally, differences between the seed and the mesocarp of studied rosehip were noticed in the content of B, Cu, Fe, K, Ni, P, S, Sr, and Ti (p < 0.05). Nutritional assessment revealed that both wild and cultivated rosehips are a valuable source of essential elements (Ca, Cu, K, Mg, Mn, and P). The absence of toxic and potentially toxic elements additionally contributes to the quality of studied Serbian rosehip. A high impact of factors such as variety, location, as well as their interaction on the content of elements in cultivated rosehip mesocarp and seed was observed. Pattern recognition techniques, principal component analysis (PCA), and hierarchical cluster analysis (HCA) were applied in order to provide insight into similarities among the analyzed samples.

Urinary trace elements in association with disease severity and outcome in patients with COVID-19

BACKGROUND

The dynamics of urinary trace elements in patients with COVID-19 still remains to be investigated.

METHODS

A retrospective study was performed on a cohort of 138 confirmed COVID-19 patients for their urinary levels of essential and/or toxic metals including chromium, manganese, copper, arsenic, selenium, cadmium, mercury, thallium and lead according to the different disease severity (severe or non-severe) and outcome (recovered or deceased).

RESULTS

Urinary concentrations of chromium, manganese, copper, selenium, cadmium, mercury and lead after creatinine adjustment were found to be higher in severe patients than the non-severe cases with COVID-19. And among the severe cases, these elements were also higher in the deceased group than the recovered group. When the weeks of the post-symptom onset were taken in account, the changes of these urinary elements were existed across the clinical course since the disease onset. These urinary elements were found to be mostly positively inter-correlated, and further positively correlated with other laboratory inflammatory parameters including serum cytokines (IL-1B, IL2R, IL6, IL8, IL10, TNFα), ferritin, and neutrophil count and white blood cell count. As a independently predictive factor, urinary creatinine-adjusted copper of ≥25.57 μg/g and ≥99.32 μg/g were associated with significantly increased risk of severe illness and fatal outcome in COVID-19, respectively.

CONCLUSIONS

These results suggest abnormities in urinary levels of the trace metals were tightly associated with the severe illness and fatal outcome of COVID-19.

Human biomonitoring of 73 elements in blood, serum, erythrocytes and urine

BACKGROUND

Human biomonitoring studies of trace elements in biological fluids are mostly limited to a certain number of elements or biological materials. In this study, we describe the significant extension of a biomonitoring to 73 elements being present in concentration ranges from ng/L to g/L in clinically relevant specimens such as blood, serum, erythrocytes and urine.

METHODS

The samples were collected from 102 occupationally non-exposed inhabitants of northern Germany. The elements were determined either by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) in the low concentration range or by inductively coupled plasma optical emission spectrometry (ICP-OES) for essential trace elements and electrolytes.

RESULTS

Mean values and selected percentiles of element concentrations are presented for all sample materials. From the results, we calculated the distribution of elements between plasma and blood cells. Application of ICP-MS/MS improves selectivity and accuracy in the determination of elements that are strongly spectrally interfered, such as Cr, Ge, Pd or Ti in blood samples.

CONCLUSIONS

This publication provides very valuable information for occupational or environmental hygienists, toxicologists and clinical chemists due to the particularly high number of determined elements and presented concentration ranges.

Profile of calories and nutrients intake in a Brazilian multicenter study of nulliparous women

Objective

To assess the calorie intake and nutritional content of the maternal diet in regions with different culinary traditions and typical foods, and to understand the nutritional profile so as to provide information about the consumption of this population and promote maternal and perinatal health.

Methods

From a cohort of 1145 pregnant women with diverse socio‐backgrounds we analyzed the dietary characteristics profile according to three guidelines and compared the differences between regions of Brazil.

Results

Women from the northeast had the lowest level of income, occupation, education, and age (P < 0.001). Intakes of unprocessed/minimally processed foods and processed foods were more prevalent in women from the northeast than in southern/southeastern women (P < 0.001). The consumption of dairy products and vegetables was less than the recommended intake, with lower intake in southern/southeastern women (P < 0.001). This study showed a lower consumption of dairy and vegetables, with a shortfall of vitamins K and D, iron, calcium, folate, magnesium, and chromium from natural and fortified foods. We observed a greater consumption of unprocessed or minimally processed food in women from the northeast of Brazil.

Conclusion

Our findings indicate the importance of differentiating the source of calorie intake between regional nutritional guidance and the diversity of local cuisine.

Data from 1145 maternal diets show adequate intake of calories but poor consumption of dairy, vegetables, and micronutrients from natural and fortified food.

An Analysis for Adulteration and Contamination of Over-the-Counter Weight-Loss Products

Six Australian and five overseas complementary medicines (CM) and meal replacement shake products were analysed for potential adulteration with two common active pharmaceutical ingredients, caffeine and sibutramine, using thin-layer chromatography and mass spectrometry. The declared amount of caffeine in each product was also reviewed. Finally, the products were examined for heavy metal contamination using inductively coupled plasma-mass spectrometry. The results showed that there was no detected adulteration of either caffeine (for those products that did not list caffeine as an ingredient) or sibutramine in the 11 products; however, based on the product labels, one Australian and one overseas (two in total) CM product contained more than the maximum daily safety limit (400 mg) of caffeine. Potentially excessive lead and/or chromium was detected in six products, including four Australian products and two products purchased online. One Australian CM product appeared to contain these heavy metals at concentrations at, or exceeding, the safety limits specified in the United States Pharmacopeia or set by the World Health Organization. The overconsumption of caffeine and heavy metals has the potential of causing significant health effects in consumers.

Selenium, Zinc, Chromium, and Vanadium Levels in Serum, Hair, and Urine Samples of Obese Adults Assessed by Inductively Coupled Plasma Mass Spectrometry

The objective of this study was to investigate of selenium (Se), zinc (Zn), chromium (Cr), and vanadium (V) levels in blood serum, hair, and urine of adult obese patients. A total of 199 lean and 196 obese subjects were enrolled in the study. Serum, hair, and urinary metal and metalloid analysis were performed by inductively coupled plasma mass spectrometry at NexION 300D (PerkinElmer Inc., USA). The results established that obese subjects were characterized by 47% and 30% lower serum Cr and V levels compared with controls, respectively, whereas serum Se levels exceeded control values by 9%. In contrast, hair Cr, Se, and V content in obese subjects exceeded the control values by 51%, 21%, and 50%, respectively. In turn, hair Zn levels were found to be significantly lower by 11% compared with the lean control values. In urine, the levels of V and Zn were found to be 30% and 18% higher in obese patients. Prevalence of hypertension in obese subjects was associated with a trend for impaired Se and Zn levels. In a regression model adjusted for age, gender, hypertension, atherosclerosis, and glucose intolerance, serum Cr, V, and hair Zn were inversely associated with body mass index (BMI), whereas hair Se was considered as the positive predictor. Our data allow proposing that the observed alterations may at least partially contribute to metabolic disturbances in obesity. In turn, monitoring of Se exposure in a well-nourished adult population is required to reduce its potential contribution to obesity.

The Double Face of Metals: The Intriguing Case of Chromium

Chromium (Cr) is a common element in the Earth’s crust. It may exist in different oxidation states, Cr(0), Cr(III) and Cr(VI), with Cr(III) and Cr(VI) being relatively stable and largely predominant. Chromium’s peculiarity is that its behavior relies on its valence state. Cr(III) is a trace element in humans and plays a major role in glucose and fat metabolism. The beneficial effects of Cr(III) in obesity and types 2 diabetes are known. It has been long considered an essential element, but now it has been reclassified as a nutritional supplement. On the other hand, Cr(VI) is a human carcinogen and exposure to it occurs both in occupational and environmental contexts. It induces also epigenetic effects on DNA, histone tails and microRNA; its toxicity seems to be related to its higher mobility in soil and swifter penetration through cell membranes than Cr(III). The microorganisms Acinetobacter sp. Cr1 and Pseudomonas sp. Cr13 have been suggested as a promising agent for bioremediation of Cr(VI). This review intends to underline the important role of Cr(III) for human health and the dangerousness of Cr(VI) as a toxic element. The dual and opposing roles of this metal make it particularly interesting. An overview of the recent literature is reported in support.

Biomonitoring of Heavy Metals: The Unexplored Role of Marine Sessile Taxa

Coastal areas are known to receive significant anthropogenic inputs, mainly deriving from metropolitan areas, industries, and activities related to tourism. Among these inputs, some trace elements are listed as priority pollutants in the European Water Framework Directive, due to their ability to bioaccumulate in organisms. Many studies have been conducted on heavy metals (HMs) accumulation and on their possible effects on different edible marine species. While the most studied sessile organisms are bivalves, in the current review, we focus our attention on other sessile taxa (sponges, cnidarians, bryozoans, polychaetes, cirripeds, and tunicates), proposed as bioindicators in coastal shallow waters. Although their potential as bioindicator tools has been repeatedly highlighted in the literature, these organisms are still poorly investigated and considered for monitoring. In this context, we analyze the available literature about this topic, in order to summarize the current knowledge and identify possible applications of these organisms in a bioremediation scenario.

Dietary chromium-methionine supplementation and broiler (22–43 days) responses during heat stress. 1. Growth performance and carcass yield, metabolisable energy and serum biochemistry

Context Chromium (Cr) is considered a beneficial trace element. It has been reported that supplementation with Cr in the diet promotes improvements in the productive variables of broilers reared under heat stress (HS). Aim The study aimed to evaluate dose response of Cr as chromium-methionine (CrMet) supplementation on metabolisable energy, serum biochemistry, growth performance and carcass yield of broilers. Methods Three hundred and thirty-six 22-day-old male broiler chickens were randomly assigned to four blocks, six treatments (0, 0.10, 0.20, 0.40, 0.80 and 1.20 mg/kg dry matter (DM) Cr as CrMet), eight repetitions with seven birds per experimental unit, subjected to HS (33°C for 12h/day) from 22 to 43 days. The supplemented CrMet level for each variable studied was estimated using linear and quadratic regressions. Key results The bodyweight was quadratically affected at 35 and 43 days (P &lt; 0.01), as well as bodyweight gain (P = 0.02) and feed conversion ratio (P = 0.01) from 22 to 43 days. A linear improvement (P = 0.03) was observed in the feed conversion ratio from 22 to 28 days and bodyweight gain for 22 to 35 days (P = 0.02). The nitrogen-corrected apparent metabolisable energy and the coefficient of metabolisation of energy were quadratically affected (P &lt; 0.01 and P &lt; 0.01, respectively) by CrMet levels in the diet. A quadratic response was observed on total serum cholesterol (P &lt; 0.01), serum glucose (P = 0.07) and triacylglycerol (P &lt; 0.01). The abdominal fat deposition was quadratically affected (P &lt; 0.01) by CrMet levels in the diet. Conclusions The supplementation of 0.77 mg/kg DM Cr as CrMet improves performance, carcass characteristics and serum biochemistry parameters of broiler chickens reared under heat stress. Implications The results indicate that CrMet can be supplemented in the diet for broilers reared under heat stress to improve productivity of broiler chickens.

A pilot study of the effects of chromium picolinate supplementation on serum fetuin-A, metabolic and inflammatory factors in patients with nonalcoholic fatty liver disease: A double-blind, placebo-controlled trial

BACKGROUND

Evaluating the impact of chromium picolinate supplementation on glycemic status, lipid profile, inflammatory markers and fetuin-A in patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

In present research, participants (N = 46) were randomized to (400 mcg/day, n = 23) chromium picolinate and placebo (n = 23) for 3 months.

RESULTS

Glucose indices, and lipid profiles, inflammatory biomarker and fetuin-A were measured before and after the intervention. Chromium reduced triglyceride (TG), atherogenic index of plasma (AIP), very-low-density lipoprotein (VLDL), insulin, homeostatic model assessment for insulin resistance (HOMA-IR), high-sensitivity C-reactive protein (hs-CRP), interleukin (IL) -6, tumor necrosis factor-alpha (TNF-α) and fetuin-A significantly compared to placebo group (p < 0.05). Furthermore, chromium significantly increased the quantitative insulin sensitivity check index (QUICKI). There were no significant differences in total cholesterol (TC), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), fasting blood sugar (FBS), Hemoglobin A1c (HbA1C), interleukin (IL)-17 between the two groups (p < 0.05).

CONCLUSION

Chromium picolinate significantly decreased TG, insulin, HOMA-IR, fetuin-A, the number of inflammatory factors, and increased QUICKI without changing FBS, HbA1C, TC, LDL, HDL, IL-17 levels and liver steatosis intensity in patients with NAFLD. Further studies by examining the effect of different doses of chromium and mechanisms of cellular action, would help further clarify the subject.

Contribution of Major Groups of Food Products to the Daily Intake of Selected Elements-Results from Analytical Determinations Supported by Chemometric Analysis

Food is a major source of minerals for humans. The main objective of this study was to determine the intake level of 10 essential macro- (Na, K, Ca, and Mg) and trace elements (Cu, Zn, Mn, Fe, Cr, and Se) with major food groups among young adults. Dietary intake of elements was evaluated using the 24-h dietary recall technique in combination with F-AAS and ICP-OES methods. A very high intake of sodium and a very low intake of calcium, combined with inappropriate sodium/potassium ratio, may be harmful to the health of the population. Dietary intake of trace elements was within the range of reference values in the subjects, with cereals being the major source of a majority of those elements, while meat (38% for Na), vegetables (25% for K), and milk products (75% for Ca) were the main contributors to the daily dietary intake of macroelements. PCA revealed several visible trends in the datasetAmong men, the intake of Zn, Cr Na and K was significantly correlated with the consumption of meat and vegetables, whereas Mg, Se, Fe and Cu with cereals and water and beverages. Among women, the intake of Mg was significantly correlated with the consumption of meat and vegetables.

Selective and sensitive fluorescent nanoprobe based on AgInS2-ZnS quantum dots for the rapid detection of Cr (III) ions in the midst of interfering ions

We herein report a novel eco-friendly method for the fluorescent sensing of Cr (III) ions using green synthesized glutathione (GSH) capped water soluble AgInS₂-ZnS (AIS-ZnS) quantum dots (QDs). The as-synthesized AIS-ZnS QDs were speherical in shape with average diameter of ∼2.9 nm and exhibited bright yellow emission. The fluorimetric analyses showed that, compared to Cr (VI) ions and other 20 metal ions across the periodic table, AIS-ZnS QDs selectively detected Cr (III) ions via fluorescent quenching. In addition, AIS-ZnS QDs fluorescent nanoprobes exhibited selective detection of Cr (III) ions in the mixture of interfering divalent metal ions such as Cu (II), Pb (II), Hg (II), Ni (II). The mechanism of Cr (III) sensing investigated using HRTEM and FTIR revealed that the binding of Cr (III) ions with the GSH capping group resulted in the aggregation of QDs followed by fluorescence quenching. The limit of detection of Cr (III) ions was calculated to be 0.51 nM. The present method uses cadmium free QDs and paves a greener way for selective determination of Cr (III) ions in the midst of other ions in aqueous solutions.

Regulations for chromium emissions to the aquatic environment in Europe and elsewhere

Chromium is a controversial element, since it has been classified as essential trace element, to chemically and biologically inert compound, to potent intoxicator. Concerns have been risen for chromium effects on human and aquatic life because chromium has been accused for genotoxicity and carcinogenesis. Metals and their ions or complexes (and thus chromium substances) are included in the indicative list of main pollutants (Annex VIII of the Water Framework Directive (2000/60/EC)). Biological effects of chromium are strongly depended on chromium speciation. No universal Cr^III or Cr^VI discharge limits to the aquatic environment have been suggested by the EU. International bodies within the EU, such as the Helsinki Commission and the Oslo-Paris Convention, have issued recommendations on chromium discharge levels. National Cr^VI and Cr^III discharge limits vary in each EU Member State with respect to the receiving water body (marine water, lake, river, sewer system). The maximum discharge limit to the aquatic environment in EU is 1 and 5 mg L^-1 for Cr^VI and Cr^total, respectively. The present work summarizes EU legislation, with respect to the discharge limits to the aquatic environment for Cr^VI and Cr^III. EU national limits that are currently effective are presented and compared to the limits in other parts of the world, such as Australia, Asia, USA, Latin America and South Africa. It is wise that future perspective of chromium policy should differentiate between Cr^III and Cr^VI discharge limits to the aquatic environment, as analytical techniques become more sensitive and chromium speciation specific, and environmental awareness rises.

Analysis of Density Changes of Selected Brain Receptors After a 14-Day Supply of Chromium(III) and Evaluation of Chromium(III) Affinity to Selected Receptors and Transporters

Chromium(III) is one of the most controversial biometals. Although, it is no longer on the list of minerals necessary for the proper functioning of the human body, and its pharmacological effect is still under discussion. One of the purposes of Cr(III) administration is to use it in patients with mood disorders and it is strictly related to its pharmacological, not dietary effect. This is because its high doses are necessary to obtain the results and additionally, no deficiencies in human population have been noted. In this study, the affinity of chromium(III) to selected receptors and transporters in the rat brain was evaluated, and the effect of the 14-day administration of this metal was assessed on the density of selected receptors. All analyses were performed in vitro using radioligand binding assays, and the results indicated lack of affinity to β₁ and α₁ receptors and serotonin transporter (SERT), furthermore very weak affinity to the 5-HT_1A receptor (30% inhibition at 10^-4 and 10^-5 M). Analysis of the α₁ and β₁ adrenergic receptor density indicated lack of any adaptive effects after 14 days of Cr(III) administration through intraperitoneal injections (doses 6 and 12 mg/kg). The antidepressant activity of chromium(III) indicated in clinical trials concerned patients with atypical, seasonal, or dystonic symptoms. This effect, as it seems based on the presented results, does not depend on direct affinity to serotonin receptors and transporter nor is the result of adaptive changes in the adrenoreceptor system.

Incidence risk of bronchopneumonia in newborn calves associated with intrauterine diselementosis

Background and Aim

Macro- and micro-elements are required to ensure the normal course of biochemical processes in the development of an animal's body. Any excess, deficiency, or imbalance in chemical elements in an animal's body can cause the development of various latent or clinically expressed pathological conditions. Diselementosis in pregnant cows may lead to impaired embryo and fetal development, as well as reduced neonatal viability. The aim of this study was to analyze the content of macroelements and microelements in the blood serum of both calving cows and their calves to evaluate the relationship between indicators of mineral metabolism in the mother and newborn and to establish what role separate chemical elements play in making newborn calves more prone to bronchopneumonia.

Materials and Methods

The content of potassium (K), sodium (Na), iron (Fe), Copper (Cu), Zinc (Zn), Strontium (Sr), arsenic (As), nickel (Ni), cobalt (Co), chromium (Cr), molybdenum (Mo), and selenium (Se) in the blood serum of 33 pregnant cows between 239 and 262 days of gestation and their 33 1-day old calves was determined using the Shimadzu AA6300 (Japan) atomic adsorption spectrophotometer. Calcium (Ca) and magnesium (Mg) content was determined using ion-selective electrodes from the Olympus-400 analyzer (Beckman Coulter, USA). During the 1^st month of life, all calves in the sample set had some sort of respiratory diseases and seven of the calves had bronchopneumonia. Retrospectively, the samples of adult and newborn animals were divided into two groups each: Dams I - cows whose calves had uncomplicated bronchitis (n=26); Dams II - cows whose calves got bronchopneumonia (n=7); and Newborns I - calves with uncomplicated bronchitis (n=26); Newborns II - calves with bronchopneumonia (n=7).

Results

The content of Ca, Mg, K, Na, Mo, and Se in dams in both groups of cows was within the reference range; the concentrations of Fe and Ni were higher than the reference range; and the concentrations of Cu, Zn, As, Co, and Cr were lower than the reference range. There were no significant differences in elemental status between the Dams I and Dams II groups. In newborn calves, the concentration of Ca and Mo corresponded to the reference range; the concentrations of Mg, Fe, Co, and Ni in both groups exceeded the reference range; and the concentrations of Cu, Zn, As, Cr, and Se were lower than the reference range. Results highlighted that there was a tendency to decrease concentration of Fe, Mo, and Se and a significant increase in the Ni concentration in calves of the Newborns II group compared with calves of the Newborns I group. It was also found that Zn, Co, Cr, and Mo actively accumulated in the body of newborn animals while the transplacental transfer of Cu, As, and Sr was limited; and transfer of Se and Ni was regulated by concentration ratios in the blood of the mother and the fetus. The excessive concentrations of Ni and Fe in the blood serum of cows and calves and the imbalance in the ratio of elements Fe-Cu-Zn, Fe-Cu-Co negatively affected erythropoiesis, formation of the immune system, and antioxidant status of the fetus and newborn. These changes were considered to be risk factors for the development of bronchopneumonia in calves.

Conclusion

An excess of serum Fe and Ni and deficiency of Cu, Zn, As, Co, and Cr in cows during the gestation period can lead to similar impairments of the mineral status in newborn calves. At the systemic level, dyslementosis in combination with the influence of other adverse factors, can lead to an increased load on the respiratory and hematopoietic systems of calves during postnatal adaptation and can subsequently cause a decrease in the natural resistance of calves and development of bronchopneumonia.

Renal bioaccumulation of trace elements in urban and rural Sri Lankan populations: A preliminary study based on post mortem tissue analysis

INTRODUCTION

Environmental pollution, especially by toxic trace elements, is a global health concern. Heavy metals such as Cadmium (Cd), Arsenic (As) and Lead (Pb) are associated with numerous disorders and are considered by some as an aetiological factor for the Chronic Kidney Disease (CKDu1) epidemic in Sri Lanka. This study explores patterns of bioaccumulation of six trace elements in kidneys obtained during forensic autopsies from urban and rural regions in Sri Lanka.

METHODS

Kidney samples obtained from one urban district (n = 13) and three rural districts (n = 18) were lyophilized, microwave digested and profiled by ICP-MS techniques.

RESULTS AND DISCUSSION

The mean age of the sampled population was 47.9 ± 11.3 yrs. Median (IQR) for Cd, As, Pb, Cr, Zn and Se were, 14.67(8.04-22.47) μg/g, 0.44(0.29-0.56) μg/g, 0.11(0.07-0.30) μg/g, 0.15(0.1096-0.3274), 25.55(17.24-39.35) μg/g and 0.52(0.37-0.84) μg/g, respectively. Cd, Zn and Se levels were significantly higher (p < 0.05) among the urban samples compared to that of the rural group. Zn and Se levels were higher among younger age groups. As, Pb and Cr did not show any significant differences between the two cohorts nor any correlations with age.

CONCLUSION

This population-specific baseline study provides an insight into the differences in exposure to toxic trace elements and essential elements between urban and rural populations. Residents in CKDu affected rural districts did not appear to be at risk of toxic heavy metal exposure, however their renal bioaccumulation of nephroprotective essential elements was lower than urban residents.

Potential use of chromium to combat thermal stress in animals: A review

Heat stress (HS) has adverse effects on the body: it decreases body weight, feed efficiency, feed intake, carcass quality, and nutrient digestibility. Chromium (Cr) can prevent lipid peroxidation induced by HS through its strong antioxidant activities, especially when it is added to the poultry diet. It improves the action of insulin and nutrient metabolism (of lipids, proteins, nucleic acid, and carbohydrates) through activation of enzymes associated with such pathways. The results of the studies on Cr added to diets with concentrations of 0.05 mg Cr/kg of Cr-methionine led to improved feed efficiency and DM intake by cows and Holstein dairy calves exposed to high environmental temperatures. Moreover, calves that received Cr at levels of 0.05 mg/kg of body weight tended to have higher serum concentrations of glucose and higher ratios of insulin to glucose. In heat-stressed pigs, Cr addition (200 ppb) increased blood neutrophils by about 37%. Several studies have asserted that Cr can inhibit inflammation in lactating cows by promoting the release of Hsp72, assisting production of IL-10 and inhibiting degradation of IκBα in HS conditions. In addition, Cr supplementation was observed to possibly have positive impacts on both cell-mediated and humeral immunity in heat-stressed buffalo calves. Studies over the last two decades have shown with certainty that chromium supplementation has an impact on many variables in chickens. Moreover, Cr is believed to increase insulin action in insulin-sensitive tissues (i.e., adipose and muscles), resulting in increased farm animal productivity through the improvement of feed intake, growth rate, carcass quality, reproductive parameters and immune functions.

Association of urinary metal concentrations with blood pressure and serum hormones in Spanish male adolescents

OBJECTIVE

To examine the association of urinary concentrations of arsenic (As), cadmium (Cd), mercury (Hg), nickel (Ni), lead (Pb), manganese (Mn), and chromium (Cr) with blood pressure (BP) and serum hormone levels in male adolescents.

METHODS

Participants were selected from the INMA (Environment and Childhood)-Granada cohort at their follow-up visit when aged 15-17 years. Metal concentrations were measured in urine samples using inductively coupled plasma mass spectrometry. Outcomes were BP measurements (systolic, diastolic, and pulse pressure) recorded during the visit and concurrent serum levels of thyroid hormones, sex hormones, and adrenal hormones. Associations were assessed by regression analysis in a sub-sample of 133 boys with available data on urinary metals, outcomes, and relevant covariates.

RESULTS

Models simultaneously adjusted for all metals and other potential confounders showed that urinary As and Cd were both associated with slight elevations in systolic BP (0.70 mmHg, 95%CI = 0.11; 1.29 and 1.47, 95%CI = 0.30; 2.63, respectively, per each 50% increase in metal concentrations), and urinary As was also associated with an increased risk of elevated systolic BP (≥120 mmHg) (OR = 1.28, 95%CI = 1.04; 1.56). The presence of detectable levels of 4 and 5 versus 2-3 non-essential metals (As, Cd, Hg, Ni, Pb) per boy was associated with elevations in systolic BP of 5.84 mmHg (95%CI = 0.40; 11.3) and 7.01 mmHg (95%CI = 1.01; 13.0), respectively (p-trend = 0.05). Significant associations were also found between Hg and increased testosterone and luteinizing hormone (LH) and decreased thyroid-stimulating hormone (TSH); between the combination of As and Hg and increased LH and insulin-like growth factor 1; between Cr and decreased TSH; and between Cd and increased adrenocorticotropic hormone.

CONCLUSIONS

These findings suggest that combined exposure to toxic metals, especially As and Cd, may contribute to BP elevation in male adolescents and that exposure to Hg, As, Cd, and Cr may affect their hormone levels.

Application of nutrient essentiality criteria to dietary carbohydrates

The purpose of the present review is to describe how human physiology at very low carbohydrate intakes relates to the criteria for nutritional essentiality. Although we did not limit ourselves to one particular type or function of carbohydrates, we did primarily focus on glucose utilisation as that function was used to determine the recommended daily allowance. In the general population, the human body is able to endogenously synthesise carbohydrates, and does not show signs of deficiency in the absence of dietary carbohydrates. However, in certain genetic defects, such as glycogen storage disease type I, absence of dietary carbohydrates causes abnormalities that are resolved with dietary supplementation of carbohydrates. Therefore, dietary carbohydrates may be defined as conditionally essential nutrients because they are nutrients that are not required in the diet for the general population but are required for specific subpopulations. Ketosis may be considered a physiological normal state due to its occurrence in infants in addition to at very low carbohydrate intakes. Although sources of dietary carbohydrates can provide beneficial micronutrients, no signs of micronutrient deficiencies have been reported in clinical trials of low-carbohydrate ketogenic diets. Nonetheless, more research is needed on how micronutrient requirements can change depending on the dietary and metabolic context. More research is also needed on the role of dietary fibre during a low-carbohydrate ketogenic diet as the beneficial effects of dietary fibre were determined on a standard diet and several studies have shown beneficial effects of decreasing non-digestible carbohydrates.

Sulforaphane attenuates hexavalent chromium-induced cardiotoxicity via the activation of the Sesn2/AMPK/Nrf2 signaling pathway

Hexavalent chromium (Cr(vi)), the most toxic valence state of chromium, is widely present in industrial effluents and wastes. Sulforaphane (SFN), rich in Brassica genus plants, bears multiple biological activity. Wistar rats were used to explore the protective role of SFN against the cardiotoxicity of chronic potassium dichromate (K2Cr2O7) exposure and reveal the potential molecular mechanism. The data showed that SFN alleviated hematological variations, oxidative stress, heart dysfunction and structure disorder, and cardiomyocyte apoptosis induced by K2Cr2O7. Moreover, SFN reduced p53, cleaved caspase-3, Bcl2-associated X protein, nuclear factor kappa-B, and interleukin-1β levels, and increased Sesn2, nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1, NAD(P)H quinone oxidoreductase-1, and phosphorylated adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) levels. This study demonstrates that SFN ameliorates Cr(vi)-induced cardiotoxicity via activation of the Sesn2/AMPK/Nrf2 signaling pathway. SFN may be a protector against Cr(vi)-induced heart injury and a novel therapy for chronic Cr(vi) exposure.

Chromium(III) Glycinate Complex Supplementation Improves the Blood Glucose Level and Attenuates the Tissular Copper to Zinc Ratio in Rats with Mild Hyperglycaemia

The aim of the study was to evaluate the hypoglycaemic potential of supplementary Cr in the form of chromium(III) glycinate (CrGly) in the diabetic model of rats. The experiment was conducted on 40 male Wistar rats, of which 30 were made diabetic by injection of a single dose of streptozotocin (55 mg/kg b.m.), while the remaining 10 rats served as the healthy control. After inducing hyperglycaemia, 2 groups of diabetic rats (10 rats each) were supplemented with Cr either as CrGly or chromium(III) picolinate (CrPic) given orally at a dose of 10 mg/kg diet (about 0.75 mg Cr/kg b.m.) with adequate AIN-93M diet for 7 weeks. At the termination of experiment, all animals were sacrificed to collect blood and internal organs for biochemical assays. Blood biochemical indices and tissular trace element contents (Fe, Zn, Cu, Cr) were measured and compared with the values of the untreated groups. It was found that CrGly significantly decreased blood glucose, total cholesterol, HDL cholesterol and triacylglycerol levels more efficiently than CrPic. Furthermore, both Cr compounds normalized disturbed the serum, renal and cardiac molar Cu/Zn ratio, as well as restored the kidney Zn and Cu levels in rats with hyperglycaemia. Supplementary Cr did not increase the tissular Cr levels in diabetic rats. The study confirmed the hypoglycaemic potential of CrGly in the diabetic model of rats.

Inhibitory effect of metals on animal and plant glutathione transferases

Glutathione transferases (GSTs) represent a widespread enzyme superfamily in eukaryotes and prokaryotes catalyzing different reactions with endogenous and xenobiotic substrates such as organic pollutants. The latter are often found together with metal contamination in the environment. Besides performing of essential functions, GSTs protect cells by conjugation of glutathione with various reactive electrophiles. The interference of toxic metals with this functionality of GSTs may have unpredictable toxicological consequences for the organisms. In this review results from the recent literature are summarized and discussed describing the ability of metals to inhibit intracellular detoxification processes in animals and plants.

Effects of chromium supplementation on body composition, human and animal health, and insulin and glucose metabolism

PURPOSE OF REVIEW

Chromium(III) has been proposed to have a nutritional or pharmacological role in changing body composition and improving symptoms of insulin resistance, type 2 diabetes, and related conditions although the mode of action of Cr(III) at a molecular level has failed to be elucidated. This review details the current status of studies into Cr(III) supplementation.

RECENT FINDINGS

Clinical trials, meta-analyses and systematic reviews have failed to demonstrate clinically significant effects from Cr(III) supplementation on body composition or symptoms of insulin resistance and related conditions in humans and farm animals. Although new Cr(III) supplements continue to appear in the scientific literature, studies have failed to elucidate the mechanism of chromium action at a molecular level. Conflicting results on a role of transferrin in Cr(III) transport and detoxification have appeared.

SUMMARY

Cr(III) supplementation cannot currently be recommended in humans or farm animals. Further studies are required to probe the mechanism of Cr(III) action in increasing insulin sensitivity and glucose uptake in rodent models of insulin resistance and diabetes, with particular attention being turned to a potential role of transferrin in Cr(III) transport and detoxification.

Safety Assessment of the Trace Element Impurities Ni and Cr in Pharmaceutical Herbal Products for Teething from Polish Pharmacies

Control of elemental impurities (EIs) in pharmaceutical herbal products is currently important but not a very popular topic in modern toxicological analysis. The occurrence and concentration of EIs in the pharmaceutical herbal products should be controlled and meet the standards of directive International Conference on Harmonisation's Q3D Guideline on Elemental Impurities. An interesting area of interest is measuring EIs including toxic and allergic metals in pharmaceutical herbal products for teething. The aim of this article was determination of Ni and Cr impurities in pharmaceutical herbal products for teething available in Polish pharmacies. Justifications were (1) herbs as an important source of EIs and (2) infants may be particularly sensitive to the toxic effects of metals because they tend to absorb a higher fraction of an oral dose. The analysis was carried out using microwave-assisted wet digestion with concentrated nitric acid and electrothermal atomisation atomic absorption spectrometry. The safety assessment involved a triple approach: (1) level of Ni and Cr impurities in pharmaceutical samples; (2) level of Ni and Cr impurities including one-time administration of teething gels and (3) daily intake of metals. In all three cases, the results indicate that the standards of directive ICH Q3D are met for Ni and Cr. Overall, it can be concluded that none of the teething gels represents a health hazard to infants.

How Plants Handle Trivalent (+3) Elements

Plant development and fitness largely depend on the adequate availability of mineral elements in the soil. Most essential nutrients are available and can be membrane transported either as mono or divalent cations or as mono- or divalent anions. Trivalent cations are highly toxic to membranes, and plants have evolved different mechanisms to handle +3 elements in a safe way. The essential functional role of a few metal ions, with the possibility to gain a trivalent state, mainly resides in the ion's redox activity; examples are iron (Fe) and manganese. Among the required nutrients, the only element with +3 as a unique oxidation state is the non-metal, boron. However, plants also can take up non-essential trivalent elements that occur in biologically relevant concentrations in soils. Examples are, among others, aluminum (Al), chromium (Cr), arsenic (As), and antimony (Sb). Plants have evolved different mechanisms to take up and tolerate these potentially toxic elements. This review considers recent studies describing the transporters, and specific and unspecific channels in different cell compartments and tissues, thereby providing a global vision of trivalent element homeostasis in plants.

Association of serum chromium levels with malnutrition in hemodialysis patients

BACKGROUND

Chromium is an essential trace metal that reduces oxidative stress and inflammation. In patients undergoing maintenance hemodialysis (MHD), a correlation among chromium exposure, inflammation, and malnutrition remains unclear. This study examined the possible effects of serum chromium levels (SCLs) in MHD patients.

METHODS

Initially, 732 MHD patients in dialysis centers were recruited. A total of 647 patients met the inclusion criteria and were stratified by SCL into four equal-sized groups: first quartile (< 0.29 μg/L), second quartile (0.29-0.56 μg/L), third quartile (0.57-1.06 μg/L), and fourth quartile (> 1.06 μg/L). Demographic, biochemical, and dialysis-related data were obtained for analyses. The analysis included nutritional and inflammatory markers.

RESULTS

As compared with the highest quartile group, more subjects in the lowest quartile group were of an older age; had lower hemoglobin and creatinine levels; had a higher prevalence of DM and malnutrition (serum albumin level < 3.6 g/dL); and higher serum transferrin saturation and ferritin levels. A stepwise multiple linear regression analysis revealed a significant negative correlation between malnutrition and SCL (β coefficient = - 0.129, p = 0.012) and negative associations among body mass index (β coefficient = - 0.010, p = 0.041), ferritin (β coefficient = - 0.107, p = 0.001) and SCL. A multivariate logistic regression analysis also demonstrated a negative correlation between malnutrition and SCL. With a 10-fold increase in SCL, the risk ratio of malnutrition was 0.49 (95% confidence interval: 0.25-0.96; p = 0.039).

CONCLUSIONS

SCL is significantly associated with malnutrition in MHD patients. Further evaluation of the relationship between clinical outcomes (morbidity/mortality) and SCL is necessitated.