Zinc status is associated with inflammation, oxidative stress, lipid, and glucose metabolism

Proteomics analysis in rats reveals convergent mechanisms between major depressive disorder and dietary zinc deficiency

BACKGROUND

Preclinical and clinical studies have shown that dietary zinc deficiency can lead to symptoms similar to those observed in major depressive disorder (MDD). However, the underlying molecular mechanisms remain unclear. To investigate these mechanisms, we examined proteomic changes in the prefrontal cortex (PFC) and hippocampus (HP) of rats, two critical brain regions implicated in the pathophysiology of depression.

METHODS

Rats were fed diets either adequate in zinc (ZnA, 50 mg Zn/kg) or deficient in zinc (ZnD, <3 mg/kg) for four weeks. High-throughput proteomic analysis was used to detect changes in protein expression, supplemented by enzyme activity assay for mitochondrial complexes I and IV, examining their functional impacts.

RESULTS

ZnD led to significant alterations in protein expression related to zinc transport and mitochondrial function. Proteomic analysis revealed changes in zinc transporter family members such as Slc30a1 (6.64 log2FC), Slc30a3 (-2.32 log2FC), Slc30a4 (2.87 log2FC), Slc30a5 (5.90 log2FC), Slc30a6 (1.50 log2FC), and Slc30a7 (2.17 log2FC) in the PFC, and Slc30a3 (-1.02 log2FC), Slc30a5 (-1.04 log2FC), and Slc30a7 (1.08 log2FC) in the HP of rats subjected to ZnD. Furthermore, ZnD significantly affected essential mitochondrial activity proteins, including Atp5pb (3.25 log2FC), Cox2 (2.28 log2FC), Atp5me (2.04 log2FC), Cyc1 (2.30 log2FC), Cox4i1 (1.23 log2FC), Cox7c (1.63 log2FC), and Cisd1 (1.55 log2FC), with a pronounced decrease in complex I activity in the PFC.

CONCLUSIONS

Our study demonstrates that ZnD leads to significant proteomic changes in the PFC and HP of rats. Specifically, ZnD alters the expression of zinc transporter proteins and proteins critical for mitochondrial function. The significant decrease in complex I activity in the PFC further underscores the impact of ZnD on mitochondrial function. These results highlight the molecular mechanisms by which ZnD can influence brain function and contribute to symptoms similar to those observed in depression.

Selective binding and fluorescence sensing of Zn(II)/Cd(II) using macrocyclic tetra-amines with different fluorophores: insights into the design of selective chemosensors for transition metals

Selective binding and optical sensing of Zn(II) and Cd(II) by L1, HL2, L3, H2L4 and H2L5 receptors were analysed in aqueous solutions by coupling potentiometric, UV-vis absorption and fluorescence emission measurements, with the aim to determine the effect of complex stability on selective signalling of metals with similar electronic configurations. All receptors share the same cyclic tetra-amine binding unit attached to a single quinoline (Q) or 8-hydroxyquinoline (8-OHQ) unit (L1 and HL2, respectively), two Q or 8-OHQ moieties (L3 and H2L4, respectively), and, finally, two Q and two acetate groups (H2L5). The crystal structures of the Cd(II) and Zn(II) complexes show that L3 and H2L4 feature a cavity in which the larger Cd(II) complex is better fitted than the Zn(II) complex, leading to the formation of more stable Cd(II) complexes. In turn, Zn(II) forms more stable complexes with L1 and HL2, owing to its high tendency to give 5-coordinated complexes. Considering optical selectivity, Zn(II) gives the most emissive complex with L3, while the corresponding Cd(II) complex is basically quenched. The gathered structure of the Zn(II) complex, in which the two Q units are associated with one another-a structural motif not observed in the [CdL3]2+ complex-leads to poor solvation of the Q units, favouring complex emission. Among 8-OHQ-containing receptors, the most emissive complex is formed by Cd(II) with HL2, containing a single 8-OHQ moiety. H2L4 forms non-emissive complexes: the presence of two coordinating 8-OHQ moieties weakens metal interactions with the tetra-amine unit, favouring PET to the excited fluorophore that quench the emission.

Highly Efficient Dual-Probe Strategy toward Single-Cell Metabolite Analysis

As cancer progresses, detached cancer cells metastasize through the circulatory system, followed by intricate metabolic rewiring for adaptation and propagation. The dynamic process of metastasis, despite being responsible for the majority of cancer-related deaths, still remains inadequately comprehended. Here, we proposed a microfluidic platform combining the dual-probe strategy for the detection of metastasize-related metabolic levels at single-cell resolution. Unique design facilitates intracellular and extracellular detection within the same cell captured at individual chambers, promoting the understanding of single-cell correlation metabolites analyses. Metabolite profiling of the model cells verified the positive correlation between upregulated intracellular NAD(P)H and the increased secretion of matrix metalloproteinases (MMPs). Furthermore, Zn2+-mediated metabolite analysis demonstrated the correlation in single cells, which could be utilized as a reference for the development of zinc-based antitumor therapies. The strategy provides valuable evidence of a relatively higher risk of metastasis for malignancies through unraveling the intricate metabolic heterogeneities arising from both intrinsic and extrinsic factors within individual cells.

Age-dependent interaction between serum zinc and triglyceride-glucose index among American adults: National Health and Nutrition Examination Survey

Introduction

Zinc plays a crucial role in glucose metabolism. The association between serum zinc and insulin resistance has recently been investigated as well, but the findings are inconsistent. The triglyceride-glucose index (TyG) is frequently utilized in epidemiological research to assess insulin resistance. The association between serum zinc levels and TyG has not yet been explored. Therefore, we designed this cross-sectional study to assess the relationship between serum zinc and TyG in adults using data from the National Health and Nutrition Examination Survey (NHANES).

Methods

A cross-sectional analysis was performed on 1,610 adults aged ≥20 years who participated in the National Health and Nutrition Examination Survey (NHANES) 2011-2016. The participants were stratified by age, and the differences in log-transformed serum zinc quartiles and TyG were further evaluated in age groups <60 years and ≥60 years using multivariable linear regression with an interaction test. Additionally, a restricted cubic spline (RCS) model was employed to examine the dose-response relationships between log-transformed serum zinc and TyG.

Results

In this cross-sectional study, a significant interaction was observed between log-transformed serum zinc and TyG in individuals aged <60 years and those aged ≥60 years when log-transformed serum zinc was transformed into a categorical variable (P-value for the likelihood ratio test for the interaction was P = 0.017). Additionally, in the fully adjusted analyses, the association between log-transformed serum zinc and TyG in the age <60 years group demonstrated a J-shaped nonlinear pattern (P for nonlinearity = 0.014), with an inflection point at ~1.94 μg/dL. While in the age ≥60 years group, it exhibited an inverted-L shaped nonlinear pattern (P for nonlinearity < 0.001***).

Conclusion

There is a significant relationship between log-transformed serum zinc and TyG in adults in the United States, with age potentially influencing this association. Further prospective studies are needed to offer additional evidence and insights into these findings.

The Presence of Food Addiction in Patients with Binge Eating Disorder Was Associated with Higher Weight, Poor Body Composition Outcomes, Lower Serum Level of Magnesium and Higher Ferritin 2 Years Post-LSG Surgery

BACKGROUND

This study examined the presence of food addiction (FA) in patients with binge eating disorder (BED) 2 years after laparoscopic sleeve gastrectomy (LSG) and explored its association with some minerals, ferritin, weight loss and, body composition outcomes.

MATERIALS AND METHODS

In this study, 120 patients with BED who had undergone LSG 2 years prior to participation were enrolled. BED was assessed using Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria and presence of FA was assessed using the Yale Food Addiction Scale (YFAS). The collected data included general characteristic, food intake, physical activity, weight loss percentage, body composition measurements such as fat mass (FM) and fat-free mass (FFM), as well as serum level of magnesium, zinc, iron, and ferritin.

RESULTS

Fifty individuals with BED met the criteria for FA disorder (41.66%). BED patients who had FA had significantly higher weight (P = 0.01) compared to those without FA. Regarding body composition changes, the finding reveals that patients with BED + FA (vs. only-BED) had a significantly lower FM loss percentage (p = 0.04) and higher FFM loss percentage (p = 0.04). The BED patients with FA had significantly lower levels of magnesium (p = 0.02) and a higher level of ferritin (p = 0.04) compared to those without FA at second year after LSG.

CONCLUSION

The presence of FA in patients with BED was associated with higher weight, poor body composition outcomes, lower serum level of magnesium, and higher ferritin two years post-LSG surgery.

Immunomodulatory Effects of Vitamin D and Zinc on Viral Infection

Several nutrients are crucial in enhancing the immune system and preserving the structural integrity of bodily tissue barriers. Vitamin D (VD) and zinc (Zn) have received considerable interest due to their immunomodulatory properties and ability to enhance the body's immune defenses. Due to their antiviral, anti-inflammatory, antioxidative, and immunomodulatory properties, the two nutritional powerhouses VD and Zn are crucial for innate and adaptive immunity. As observed with COVID-19, deficiencies in these micronutrients impair immune responses, increasing susceptibility to viral infections and severe disease. Ensuring an adequate intake of VD and Zn emerges as a promising strategy for fortifying the immune system. Ongoing clinical trials are actively investigating their potential therapeutic advantages. Beyond the immediate context of the pandemic, these micronutrients offer valuable tools for enhancing immunity and overall well-being, especially in the face of future viral threats. This analysis emphasizes the enduring significance of VD and Zn as both treatment and preventive measures against potential viral challenges beyond the current health crisis. The overview delves into the immunomodulatory potential of VD and Zn in combating viral infections, with particular attention to their effects on animals. It provides a comprehensive summary of current research findings regarding their individual and synergistic impacts on immune function, underlining their potential in treating and preventing viral infections. Overall, this overview underscores the need for further research to understand how VD and Zn can modulate the immune response in combatting viral diseases in animals.

Enhancing broiler growth and carcass quality: impact of diets enriched with Moringa oleifera leaf powder conjugated with zinc nanoparticles

This study evaluated the effects of Moringa oleifera leaf powder extract stabilized with zinc nanoparticles (ZnNPs-MLPE) as a natural growth promoter in broiler diets. Randomly assigned 264 one-day-old Ross 308 chicks to four different feeding treatments, with each group being subdivided into six replicates, each comprising 11 unsexed chicks. The control group was fed a basic diet without additives, while the experimental groups were supplemented with 1.0, 2.0, or 3.0 cm³ of ZnNPs-MLPE/L of diet. The findings demonstrated that 2.0 and 3.0 cm³/L ZnNPs-MLPE supplementation significantly enhanced live body weight (LBW) and weight gain (BWG). Feed intake (FI) and feed conversion ratio (FCR) did not show significant differences between the treated groups and the control, indicating that the additive did not negatively affect feed efficiency. However, an increase in abdominal fat was noted in the ZnNPs-MLPE treatments relative to the control. Blood analysis revealed that the ZnNPs-MLPE groups had significantly lower levels of "total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), and alanine transaminase (ALT) compared to the control group. In contrast, total protein (TP), albumin, and the albumin/globulin (A/G) ratio" were higher in the ZnNPs-MLPE groups. Immunoglobulins IgY and IgM, as well as superoxide dismutase (SOD) levels, were elevated. Malondialdehyde (MDA) levels were reduced, indicating improved antioxidant capacity and immune function in the ZnNPs-MLPE-treated groups. In conclusion, supplementation with ZnNPs-MLPE at 2.0 and 3.0 cm³/L positively impacted broiler growth efficiency, antioxidant capacity, and immunological functionality. These findings support the potential of ZnNPs-MLPE as an effective natural growth enhancer for producing healthier poultry products.

Multi-Omics Assessment of Puff Volume-Mediated Salivary Biomarkers of Metal Exposure and Oxidative Injury Associated with Electronic Nicotine Delivery Systems

BACKGROUND

Since their inception, electronic nicotine delivery systems (ENDS) have gained increasing popularity, sparking a vaping epidemic among adolescents in the US and globally. Several ENDS safety concerns have emerged as device features and formats that contribute to heavy metal exposure and toxicity continue to evolve and outpace regulatory efforts.

OBJECTIVES

Our objective was to integrate ENDS emission profiles with salivary proteome and metabolome data to characterize exposure factors that may influence adverse vaping-mediated health outcomes.

METHODS

A total of 56 participants (38 exclusive ENDS users and 18 non-ENDS users) were recruited. A subset of 15 exclusive ENDS users completed puffing topography assessments to obtain individual vaping behavior patterns using each participant's ENDS device. Inductively coupled plasma mass spectrometry was used to determine the metal content of emissions (12 ENDS devices) generated using a programmable ENDS aerosol generation system and saliva (15 exclusive ENDS users and 5 non-ENDS users). Saliva samples from 10 exclusive ENDS users and 5 non-ENDS users were analyzed for proteomic, metabolomic, inflammatory, and oxidative stress/damage biomarkers.

RESULTS

A linear puff volume-dependent increase in particle emissions and heavy metals was observed in ENDS aerosols and saliva of exclusive ENDS users. Elevated puff volume-dependent levels of salivary cytokines, including tumor necrosis factor-alpha (TNFα ), interleukin-1 beta (IL-1β ), and IL-6, were observed alongside the oxidative damage indicators malondialdehyde (MDA), superoxide dismutase (SOD), and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Proteome-metabolome network analysis showed a higher risk of potentially developing neurological and respiratory diseases in ENDS users compared with non-ENDS users. Integrated salivary proteome-metabolome-metallome network analysis further demonstrated that heavy metals were associated with proteomic and metabolomic perturbations, with notable alterations in inflammatory response, immune function, and disease-related pathways.

DISCUSSION

A significant correlation between heavy metals, cytokines, and oxidative stress markers reveals a potential role of vaping behavior in exposure to metals and changes in markers associated with DNA damage and inflammation. Our study demonstrates the importance of characterizing vaping behavior and puffing topography when examining the human health implications of ENDS use. https://doi.org/10.1289/EHP14321.

Effect of Cashew Nut Consumption on Biomarkers of Copper and Zinc Status in Adolescents with Obesity: A Randomized Controlled Trial

BACKGROUND

Children and adolescents with obesity have altered serum copper (Cu) and zinc (Zn) levels, which are associated with oxidative stress, inflammation, and health outcomes. The inclusion of cashew nuts in an adequate diet may provide health benefits and help improve the mineral status of individuals with obesity.

OBJECTIVE

To evaluate the effects of cashew nut consumption on biomarkers of Cu and Zn status in adolescents with obesity.

METHODS

This was a randomized controlled trial conducted in adolescents. The participants were divided into a control group (CON) and a cashew nut group (CASN). The CASN group received 30 g/day of roasted cashew nuts for 12 weeks, and both groups received nutritional counseling during the study. Anthropometric, dietary, and biochemical parameters (Zn, Cu, and superoxide dismutase (SOD)) were assessed at the baseline and at the end of the study. Association tests, within-group and between-group mean comparisons, and analyses of variation between study periods (Δ T12-T0) were performed.

RESULTS

The sample consisted of 81 adolescents who completed the intervention period, resulting in 54 in the CASN group and 27 in the CON group. After the intervention, the CASN group presented a decrease in plasma Cu (p = 0.004) and an increase in SOD (p = 0.030). Both groups showed an increase in plasma Zn (p < 0.050) and a decrease in the Cu/Zn ratio (p < 0.001). CASN had a negative effect on the Cu concentration, which was significantly different from that of CON (p = 0.004).

CONCLUSIONS

The consumption of cashew nuts for 12 weeks reduced plasma Cu levels in adolescents with obesity. Nutritional counseling may have contributed to the increase in plasma Zn levels in all the study participants.

Importance of trace elements in the immunometabolic health of people living with HIV/AIDS: a literature review

Trace elements (TEs) are essential for human health and for maintaining immune responses against potentially aggressive pathogens, such as the human immunodeficiency virus (HIV). During the infectious process, the body needs greater amounts of TEs in order to coordinate an efficient immune response to combat the invading agent, a condition that reflects in lymphocyte proliferation and activation of the antioxidant defense system of neutrophils and macrophages. Thus, during the progression phase of a viral infection, immunomodulation of TEs such as iron, zinc, chromium, magnesium, selenium, copper, calcium, and manganese occurs, can lead to immunosuppression and increased oxidative stress. Furthermore, the adverse effects caused by the use of antiretroviral therapy (ART) trigger nutritional disorders and metabolic alterations that contribute to deficiencies in TEs, associated with compromised immune function. Therefore, this narrative literature review aims to contribute as a teaching tool on the TEs involved in the pathogenesis of HIV, by reviewing the role of TEs in the immunometabolic health of people living with HIV/AIDS.

Association of urinary levels of trace metals with type 2 diabetes and obesity in postmenopausal women in Korea: A community-based cohort study

Several toxic metals have been associated with metabolic diseases like obesity and diabetes mellitus (DM) in humans. However, knowledge regarding the influence of many trace elements, especially in combination with essential elements is limited. This study aims to address this research gap by investigating the associations of both non-essential and essential inorganic trace elements in urine with DM and obesity, employing a group of postmenopausal women (n = 851) from the Korean Genome and Epidemiology Study (KoGES) cohort. Urine samples were collected during 2017-2018, and were analyzed for 19 trace elements using inductively coupled plasma-mass spectrometry and an automatic mercury analyzer. Outcomes of interest were metabolic diseases (DM and obesity) and DM-related traits (insulin resistance and β-cell function). After adjustment of covariates, such as age, alcohol consumption, smoking status, educational level, and daily energy intake, urinary Zn, Ni, Tl, and U levels were associated with the prevalence of DM and homeostatic model assessment (HOMA) for insulin resistance (IR) in the postmenopausal women. In the whole mixture model, however, no significant association was observed for the prevalence of DM. Urinary levels of Zn were negatively associated with HOMA of β-cell function (HOMA-β), positively correlated with HbA1c levels, HOMA-IR, and prevalent DM. In addition, urinary Zn, Co, Tl, and Cs were positively associated with obesity (body mass index ≥25 kg/m2). The present observation shows that several individual elements and their mixtures may be associated with the prevalence of DM, IR, or obesity.

The Effect of Zeolite Zinc on Memory Performance and Hippocampal Cell Death in a Rat Model of Alzheimer's-like Disease Induced by Aβ1-42

Alzheimer's disease (AD) is one of the most common neurodegenerative disorders, characterized by the slow and progressive loss of brain structure and function, primarily affecting older individuals. Evidence has shown that disruption of zinc homeostasis in the brain contributes to synaptic dysfunction, as well as impairments in learning and memory. In this study, we evaluated the effect of zeolite zinc on memory performance and hippocampal cell death in a rat model of Alzheimer's disease (AD) induced by intracerebroventricular administration of Aβ1-42. We employed the Morris water maze, shuttle box, and open field tests to assess spatial memory, passive avoidance memory, and anxiety-like behavior, respectively. P-Tau and the amyloid precursor protein (APP) expression, along with hippocampal cell death, were also evaluated. Both Aβ1-42 and zeolite zinc were injected intracerebroventricularly. The results showed that zeolite zinc partially reversed Aβ1-42-induced impairments in memory performance and mitigated the effects of Aβ1-42 on locomotor activity, although it did not fully restore baseline levels. In addition, Aβ1-42 increased the expression of APP and P-Tau, as well as the number of dead cells, whereas zeolite zinc reduced these effects. In conclusion, our findings suggest that while zeolite zinc plays a role in modulating the pathophysiology of AD, its therapeutic effects only partially reverse the progression or symptoms of AD, indicating the need for further investigation into optimal dosing or combination therapies.

The role and mechanism of various trace elements in atherosclerosis

Atherosclerosis is a slow and complex disease that involves various factors, including lipid metabolism disorders, oxygen-free radical production, inflammatory cell infiltration, platelet adhesion and aggregation, and local thrombosis. Trace elements play a crucial role in human health. Many trace elements, especially metallic ones, not only maintain the normal functions of organs but also participate in basic metabolic processes. The latest studies have revealed a close correlation between trace elements and the occurrence and progression of atherosclerosis. The imbalance of these trace elements can induce atherosclerosis or accelerate its progression through various mechanisms, which poses a significant threat to human health. Therefore, exploring the specific mechanism of trace elements on atherosclerosis is highly significant. In this review, we summarized the roles and mechanisms of iron, copper, zinc, magnesium, and selenium homeostasis and imbalance in atherosclerosis development, in order to identify novel targets and therapeutic strategies for treating atherosclerosis.

Genetic insights into the effect of trace elements on cardiovascular diseases: multi-omics Mendelian randomization combined with linkage disequilibrium score regression analysis

Objective

Epidemiological evidence indicates that trace elements are significantly associated with cardiovascular health. However, its causality and underlying mechanisms remain unclear. Therefore, this study aimed to investigate the causal relationship between trace elements and cardiovascular disease, as well as their potential mechanism of action.

Method

Two-sample Mendelian randomization (MR) analyses along with mediated and multivariate MR analyses were employed. These analyses utilized 13 trace elements as exposure variables and 20 cardiovascular diseases as outcome variables, with 4907 circulating plasma proteins, 1400 serum metabolites, 731 immune cell phenotypes, and 473 intestinal flora as potential mediators. The Bayesian weighted MR method was used to validate the MR results, and linkage disequilibrium score regression (LDSC) was applied to explore the genetic correlation between trace elements and cardiovascular disease.

Result

Our findings indicated a positive or negative causal relationship between genetically predicted trace elements and cardiovascular disease. An analysis using the Bayesian weighted MR method demonstrated that our causal inference results were reliable. The results of the mediated MR analyses indicate that potassium may reduce the risk of ischemic heart disease by influencing the expression of the plasma proteins BDH2 and C1R. Vitamin B12 may increase the risk of coronary atherosclerosis and cardiovascular death by reducing the levels of VPS29 and PSME1 proteins, while vitamin C may mitigate the risk of cardiac arrest by inhibiting the expression of the TPST2 protein. In addition, potassium can reduce the risk of ischemic heart disease by lowering 4-methoxyphenyl sulfate levels. None of the instrumental variables exhibited pleiotropy in the MR analysis. A sensitivity analysis using the leave-one-out method further confirmed the robustness of our findings. LDSC results indicated a genetic correlation between multiple trace elements and various cardiovascular diseases.

Conclusion

This study uncovered the true causal relationship between trace elements and cardiovascular disease risk using genetic methods, and revealed the significant mediating role of specific plasma proteins and metabolites in this relationship.

Association of multiple urinary metals/metalloids with obesity defined by body fat percentage: A cross-sectional study among Guangxi Zhuang ethnic in China

BACKGROUND

Previous studies confirmed a link between urinary metals/metalloids and obesity; however, the majority of these studies defined obesity using body mass index (BMI) or waist circumference (WC), and their results were not constantly consistent. Studies defining obesity based on body fat percentage (BFP) is less reported.

METHODS

A total of 5405 participants aged 35-74 from Guangxi Zhuang ethnic group in China were included in the analysis. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect the concentrations of 22 metals/metalloids in urine. Using a binary logistic regression model, the impact of individual metal/metalloid on the risk of BFP/obesity was analyzed, and the LASSO regression model was employed to choose metals/metalloids independently related with BFP/obesity to construct a multiple-metal models. The quantile g-computation model was used to evaluate the combined impacts of metals/metalloids on BFP/obesity.

RESULTS

In multiple-metal models, compared with the lowest quartile, the highest quartile of urinary concentrations of Mg, Cd, and Ti was significantly associated with a reduced risk of BFP/obesity (Mg: OR=0.66, 95 %CI: 0.51, 0.85; Cd: OR=0.63, 95 %CI: 0.49, 0.82; Ti: OR=0.73, 95 %CI: 0.57, 0.93). Conversely, the highest quartiles of urinary concentrations of Zn, V, and Sb was significantly associated with an increased risk of BFP/obesity (Zn: OR=1.75, 95 %CI: 1.39, 2.22; V: OR=1.63, 95 %CI: 1.25, 2.14; Sb: OR=1.38, 95 %CI: 1.06, 1.79). In quantile g-computation analysis, Mg, Cd, and Sn were the main contributors to negative effects, while Zn, V, and Sb were the main contributors to positive effect, although no significant relationship was observed between the multiple metal/metalloid mixtures and BFP/obesity.

CONCLUSIONS

According to our study, urinary Mg, Cd, and Ti levels were negatively associated with BFP/obesity risk, and Zn, V, and Sb levels were positively associated with BFP/obesity risk. However, these associations need to be further verified by longitudinal studies, and the molecular mechanisms need to be further explored by animal and cell experiments.

Effects of Zinc Compounds on the Enzymatic Activities of Lysozyme and Peroxidase and Their Antifungal Activities

This study aimed to investigate the effects of zinc compounds on the enzymatic activities of lysozyme, peroxidase, and the glucose oxidase-mediated peroxidase (GO-PO) system and their antifungal activities. Four different zinc compounds (zinc chloride, gluconate, lactate, and sulfate) were incubated with hen egg-white lysozyme (HEWL), bovine lactoperoxidase (bLPO), the GO-PO system, and human unstimulated whole saliva in solution and on a hydroxyapatite surface. Enzymatic activities of lysozyme, peroxidase, and the GO-PO system were measured through the hydrolysis of Micrococcus lysodeikticus, oxidation of fluorogenic 2',7'-dichlorofluorescin, and glucose assay, respectively. Interactions between zinc and enzymes were analyzed by surface plasmon resonance (SPR). The minimum inhibitory concentration (MIC) and candidacidal activities of zinc compounds were examined against three Candida albicans strains. Zinc gluconate and sulfate significantly increased the enzymatic activities of salivary lysozyme in the solution assay and of HEWL and salivary lysozyme on the hydroxyapatite surface. However, all examined zinc compounds significantly decreased the enzymatic activities of bLPO and salivary peroxidase in solution and on the surface. SPR analyses revealed binding of zinc to lysozyme and peroxidase, with affinity differing according to the zinc compounds. The MIC of zinc compounds against C. albicans was 1.0-2.4 mM. Candidacidal activities were 17.7-38.8% and 23.7-47.0% at 1.0 and 10 mM concentrations, respectively. In conclusion, zinc compounds enhanced lysozyme activity but inhibited peroxidase activity. Zinc compounds exhibited concentration-dependent candidacidal activity against C. albicans. Zinc compounds are potential therapeutic agents for oral health, especially for geriatric patients.

Paternal zinc deficiency alters offspring metabolic status in Drosophila melanogaster

BACKGROUND

This study delves into the understudied yet potentially crucial role of paternal zinc deficiency in programming offspring metabolic outcomes. By examining paternal zinc deficiency, we aim to shed light on a previously unexplored avenue with the potential to significantly impact future generations. We investigated the intergenerational effects of paternal zinc deficiency on metabolic parameters in Drosophila melanogaster.

METHODS

Dietary zinc deficiency was induced by supplementing the diet of Drosophila F0 male flies with TPEN (N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine) from egg stage. The F0 male flies after eclosion were mated with age-matched virgin female flies from the control group, resulting in the F1 offspring generation. The F1 generation were then cultured on a standard diet for subsequent metabolic analyses, including assessments of body weight, locomotion, and levels of glucose, trehalose, glycogen, and triglycerides as well as the expression of related genes.

RESULTS

We observed an increase (p<0.05) in body weight in male parent flies and female offspring. Negative geotaxis performance was also impaired in the female offspring. Paternal zinc deficiency exerted distinct effects on carbohydrate and lipid metabolism, as evidenced by a significant (p<0.05) increase in trehalose and triglyceride levels in both parent and offspring. Additionally, zinc deficiency led to alterations in the expression of key metabolic genes, including significant (p<0.05) increase in DILP2 mRNA levels, highlighting potential links to insulin signaling. Also, there were reduced mRNA levels of SOD1 and CAT in both parental and offspring generations. Parental zinc deficiency also increased the expression of Eiger and UPD2 mRNA in the offspring, suggesting potential perturbations in the immune response system.

CONCLUSION

These findings underscore the link between zinc status and various physiological and molecular processes, revealing both immediate and intergenerational impacts on metabolic, antioxidant, and inflammatory pathways and providing valuable insights on the implications of paternal zinc deficiency in Drosophila melanogaster.

Vitamin D3 and zinc supplements augment the antimanic efficacy of lithium and olanzapine treatments in an animal model of mania

Objective: Bipolar disorder (BD) is a challenging psychiatric disorder and a complex disease. The associated reduction in serum vitamin D3 (VitD3) levels in BD patients and the contribution of zinc (Zn) to the treatment, along with the severe side effects of lithium (Li) treatment, were encouraging to assess the efficacy of different correlated combinations of therapeutic/nutraceutical treatments such as olanzapine (Oln), VitD3, and Zn against Li. Methods: Mania was induced in C57BL/6 mice by administering methylphenidate (MPH) for 14 consecutive days. On the 8th day of MPH injection, different treatment regimens were administered, Li, Oln, VitD3/Zn, VitD3/Zn/Oln, VitD3 + Zn + Oln + Li50mg/kg (C50), and VitD3 + Zn + Oln + Li100mg/kg (C100). Both VitD3 (850 IU/kg) and Zn (180 mg/kg) were supplied with food for 2 weeks before starting the induction of mania, which continued until the end of MPH administration. Behavioral, brain oxidative stress, thyroid hormones, VitD3, Zn, GsK-3β, and Bcl2 levels, as well as brain histopathological alterations, were assessed. Results: Manic mice exhibited alterations in all tested parameters, and the histopathological examination of the cortex and hippocampus confirmed these results. The VitD3/Zn/Oln, C50, and C100 treatment regimens reversed most of the behavioral and pathophysiological alterations; however, the C50 treatment regimen was the most efficient. Conclusions: This study emphasizes the importance of combining different antimanic medications like Li and Oln with nutraceutical supplements to increase their antimanic efficacy, reduce their adverse effects, and, ideally, improve the BD patient's quality of life.

Exploring potential mechanisms for zinc deficiency to impact in autism spectrum disorder: a narrative review

Autism spectrum disorder (ASD) is a heterogeneous and complex group of life-long neurodevelopmental disorders. How this clinical condition impacts an individual's intellectual, social and emotional capacities, contributing to alterations in the proprioceptive and sensory systems and increasing their selective attitude towards food, is well described in the literature. This complex condition or status exposes individuals with ASD to an increased risk of developing overweight, obesity and non-communicable diseases compared with the neurotypical population. Moreover, individuals with ASD are characterised by higher levels of inflammation, oxidative stress markers and intestinal dysbiosis. All these clinical features may also appear in zinc deficiency (ZD) condition. In fact, zinc is an essential micronutrient for human health, serving as a structural, catalytic and regulatory component in numerous physiological processes. The aim of this narrative review is to explore role of ZD in ASD. Factors affecting zinc absorption, excretion and dietary intake in this vulnerable population are taken into consideration. Starting from this manuscript, the authors encourage future research to investigate the role of ZD in ASD. The perspective is to potentially find another missing piece in the 'ASD clinical puzzle picture' to improve the health status of these individuals.

Dietary supplementation of poly-dihydromyricetin-fused zinc nanoparticles alleviates fatty liver hemorrhagic syndrome by improving antioxidant capacity, intestinal health and lipid metabolism of laying hens

Fatty liver hemorrhagic syndrome is the main cause of noninfectious death of laying hens and results in substantial economic losses to the poultry industry. This study focused on evaluating the effects of Poly-dihydromyricetin-fused zinc nanoparticles (PDMY-Zn NPs) on antioxidant capacity, liver lipid metabolism, and intestinal health in laying hens. A total of 288 Jingfen laying hens (52 wk old) with similar body weights were randomly divided into 4 dietary groups with 6 replicates in each group for 8 wk. The control group received a basal diet, while the treatment groups were supplemented with PDMY-Zn NPs at levels of 200, 400, and 600 mg/kg, respectively. The results indicate that PDMY-Zn NPs supplementation can enhance antioxidant parameters (P < 0.05) in the blood and liver of laying hens. Simultaneously, it can mitigate vacuolar degeneration and inflammatory necrosis in hepatocytes, improve the relative expression level of related parameters associated with liver lipid metabolism and key regulatory genes (P < 0.05). Furthermore, it has been observed to reshape the composition and diversity of cecum microbes by increasing beneficial probiotics such as Lactobacillus and Prevotella, while also enhancing villi height and villi/crypt ratio in the duodenum and ileum (P < 0.05). Additionally, it elevates liver bile acid content along with the relative expression of key genes involved in liver synthesis (P < 0.05). In summary, PDMY-Zn NPs showed potential to alleviate fatty liver hemorrhagic syndrome by enhancing antioxidant capacity, regulating liver lipid metabolism, and maintaining intestinal health.

Association of Zinc Intake, Tobacco Smoke Exposure, With Metabolic Syndrome: Evidence from NHANES 2007-2018

The objective was to explore the effect modification of zinc (Zn) intake levels on the relationship of tobacco smoke exposure and risk of metabolic syndrome (MetS) in children and adolescents. We used data from 2007-2018 National Health and Nutrition Examination Survey (N = 3701). MetS was considered as main endpoint. Weighted multivariable logistic regression models showed that high cotinine level (≥ 0.05 ng/mL) was associated with increased odds of MetS [odds ratio = 1.54, 95% confidence interval: 1.01, 2.36], and the association between Zn intake levels and MetS did not demonstrate statistical significance. Importantly, the multiplicative interaction term between low Zn intake (≤ 4.89 mg/1000 kcal) and high cotinine level was related to higher odds of MetS (p-value for interaction 0.018). For the group with low Zn intake, high cotinine level was associated with increased odds of MetS. However, there was no significant relationship between cotinine levels and MetS risk in the group with high Zn intake. The effect modification by Zn intake on the relationship of tobacco smoke exposure and risk of MetS is significant in individuals who had a sedentary time of ≥ 6 h, identified as non-Hispanic White, or resided in households with smokers. In short, low Zn intake may potentiate the association of tobacco smoke exposure and MetS risk in children and adolescents.

Elements in trace amount with a significant role in human physiology: a tumor pathophysiological and diagnostic aspects

Cancer has a devastating impact globally regardless of gender, age, and community, which continues its severity to the population due to the lack of efficient strategy for the cancer diagnosis and treatment. According to the World Health Organisation report, one out of six people dies due to this deadly cancer and we need effective strategies to regulate it. In this context, trace element has a very hidden and unexplored role and require more attention from investigators. The variation in concentration of trace elements was observed during comparative studies on a cancer patient and a healthy person making them an effective target for cancer regulation. The percentage of trace elements present in the human body depends on environmental exposure, food habits, and habitats and could be instrumental in the early diagnosis of cancer. In this review, we have conducted inclusive analytics on trace elements associated with the various types of cancers and explored the several methods involved in their analysis. Further, intricacies in the correlation of trace elements with prominent cancers like prostate cancer, breast cancer, and leukaemia are represented in this review. This comprehensive information on trace elements proposes their role during cancer and as biomarkers in cancer diagnosis.

Effect of Zinc on Blood Biochemical and mTOR Gene Expression in Rats with Polycystic Ovarian

Zinc (Zn) is a significant element of the reproductive system and is associated with several enzymes that regulate different metabolic pathways. Organic Zn can significantly affect polycystic ovarian syndrome (PCOS) pathogenesis. Insulin resistance (IR) is a common complication of PCOS. Mammalian target of rapamycin (mTOR), which controls crucial cell functions, is regulated by insulin and nutrients. It has two complexes, namely, mTORC1 and mTORC2. mTOR associates with its binding partner's regulatory associated protein of mTOR (Raptor) and rapamycin-insensitive companion of mTOR (Rictor), which form these distinct complexes, respectively, and is activated in PCOS. This research aimed to evaluate the effect of Zn on the expression of mTOR signaling genes (Raptor and Rictor) and IR in PCOS model rats. Different Zn supplements, including standard diet (SD): (control - or + , SD without supplementation), Zn25, Zn75, and Zn175 (daily given three levels of 25, 75, and 175 mg Zn methionine (ZnMet)/kg for 6 weeks, respectively), were applied to the control and PCOS groups. Fasting glucose (FG), fasting insulin (FI), IR indices, and Raptor and Rictor expression levels were measured in both groups. The results showed that PCOS induction dramatically increased FG, FI, IR indices, and mTOR-related gene expression; however, different Zn supplementation concentrations, especially at 75 mg/kg, reduced the effects of PCOS induction. Organic Zn collectively exerted positive effects on Estradiol Valerate (EV)-induced PCOS rats by reducing IR and mTOR signaling gene (i.e., Raptor and Rictor) expression. Moreover, this study revealed a correlation between Zn and IR. Therefore, Zn supplementation could be a valuable therapeutic method for treating PCOS.

Increasing sustainability and reproducibility of in vitro toxicology applications: serum-free cultivation of HepG2 cells

Fetal Bovine Serum (FBS) is an important ingredient in cell culture media and the current standard for most cells in vitro. However, the use of FBS is controversial for several reasons, including ethical concerns, political, and societal pressure, as well as scientific problems due to the undefined and variable nature of FBS. Nevertheless, scientists hesitate to change the paradigm without solid data de-risking the switch of their assays to alternatives. In this study, HepG2 cells, a human hepatoblastoma cell line commonly used to study drug hepatotoxicity, were adapted to serum-free conditions by using different commercially available media and FBS replacements. After transition to these new culture conditions, the success of adaptation was determined based on cell morphology and growth characteristics. Long-term culturing capacity for each medium was defined as the number of passages HepG2 cells could be cultured without any alterations in morphology or growth behavior. Two media (Advanced DMEM/F12 from ThermoFisher and TCM® Serum Replacement from MP Biomedicals) showed a long-term cultivation capacity comparable to media containing FBS and were selected for further analysis. Both media can be characterized as serum-free, however still contain animal-derived components: bovine serum albumin (both media) and bovine transferrin (only TCM® serum replacement). To assess the functionality of the cells cultivated in either of the two media, HepG2 cells were treated with reference compounds, specifically selected for their known hepatotoxicity characteristics in man. Different toxicological assays focusing on viability, mitochondrial toxicity, oxidative stress, and intracellular drug response were performed. Throughout the different assays, response to reference compounds was comparable, with a slightly higher sensitivity of serum-free cultivated HepG2 cells when assessing viability/cell death and a lower sensitivity towards oxidative stress. Taken together, the two selected media were shown to support growth, morphology, and function of serum-free cultivated HepG2 cells in the early preclinical safety space. Therefore, these results can serve as a starting point to further optimize culture conditions with the goal to remove any remaining animal-derived components.

Preparation of antibacterial composite film based on arginine-modified chitosan and its application in the preservation of ready-to-eat sea cucumber

An edible composite film was developed and applied for ready-to-eat sea cucumber storage to improve the product quality. The PAC film base is first prepared by mixing 0.5 % glycerin (GL) with 4 % polyvinyl alcohol (PVA) and 1 % arginine-modified chitosan (Arg-CTS) in the same volume. After the addition of nano-ZnO (ZnO) and thymol (Thy) to the PAC film base, the mechanical properties and functions were tested. Compared to the PAC film, the PAC-ZnO-ThyH composite film showed a 1.34-fold increase in the DPPH scavenging rate and a 2.19-fold increase in the ABTS scavenging rate. Contrary to the PAC film, the inhibition zone diameter of Escherichia coli and Staphylococcus aureus significantly increased by 2.35 and 4.08 folds in the PAC-Zno-ThyH film, respectively. After applying the PAC-ZnO-ThyH film to store ready-to-eat sea cucumber for 10 days, there was a significant reduction in weight loss, total volatile basic nitrogen (TVB-N), and lipid oxidation levels to 1.47 and 1.26 folds to the Ctrl group. After preservation, the hardness and chewiness of ready-to-eat sea cucumber were maintained at 1079.62 ± 138.86 N and 913.73 ± 175.79 N, respectively. The novel PAC-ZnO-ThyH composite film can be used as an active food packaging for promising seafood applications.

Micronutrients and Androgenetic Alopecia: A Systematic Review

SCOPE

Hair loss is a common problem that can negatively impact individuals' psychological well-being. Androgenetic alopecia (AGA) is one of the most prevalent types of nonscarring hair loss. This review summarizes the existing evidence on the relationship between AGA and various micronutrients, including vitamin B, vitamin D, vitamin A, vitamin C, iron, selenium, zinc, manganese, and copper.

METHODS

A literature search was conducted to identify relevant articles published between 1993 and 2023. The search identified 49 relevant articles.

RESULTS

The findings suggest that deficiencies or imbalances in these micronutrients may contribute to the pathogenesis of AGA and represent modifiable risk factors for hair loss prevention and treatment. Vitamin B, vitamin D, iron, and zinc appear to play critical roles in hair growth and maintenance. Deficiencies in these micronutrients have been associated with increased risk of AGA, while supplementation with these nutrients has shown potential benefits in improving hair growth and preventing hair loss. However, the current evidence is not entirely consistent, with some studies reporting no significant associations.

CONCLUSION

Deficiencies or imbalances in specific vitamins and minerals, especially vitamin B, vitamin D, Fe, Se, and Zn are involved in the pathogenesis of AGA and may represent modifiable risk factors for the treatment and prevention of this condition.

Effects of deep-sea water on training efficiency, locomotor function and respiratory metabolism in young and aged mice

Deep sea water (DSW) contains many trace minerals, and its applications, which include its use as drinking water, have gradually been expanding. Generally, humans tend to be lacking in mineral intake and deficiencies of trace minerals may increase the risk of several health problems. In recent years, the lack of exercise among the elderly has become an issue, leading to the onset of frailty and sarcopenia, which in turn increases the risk of dementia. Therefore, we investigated whether the daily intake of DSW-extract-added water (DSW; hardness 300 mg/L) impacted the training effect in aged mice. Treatment with DSW significantly induced a training effect in aged mice subjected to treadmill exercise. Locomotor function and metabolic capacity were also significantly increased in aged mice after DSW treatment. The results indicate that daily intake of DSW may enhance the training effect of exercise and affect locomotor performance.

Association between dietary antioxidant levels and diabetes: a cross-sectional study

Background

The onset and progression of diabetes mellitus (DM) is strongly linked to oxidative stress. Previous studies have highlighted the protective effects of individual dietary antioxidants against diabetes. However, the relationship between a comprehensive combination of dietary antioxidants and diabetes has rarely been examined. Therefore, this study assessed the association between various dietary antioxidant intake levels and diabetes among US adults and further investigated potential associations using the Composite Dietary Antioxidant Index (CDAI).

Methods

The study employed data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2011 and 2018 for cross-sectional analysis. Dietary information was obtained from two 24-h dietary recall interviews. The CDAI was calculated using intakes of six dietary antioxidants from the dietary information. Multifactorial logistic regression models were employed to investigate the association of different dietary antioxidants and CDAI with DM. The relationship between CDAI and DM was further explored using subgroup analyses and restricted cubic spline curves.

Results

A total of 7,982 subjects (mean age 47.32 ± 16.77 years; 48.50% male and 51.50% female) were included in this study. In the multivariate-adjusted single antioxidant model, vitamin C intake was significantly and negatively associated with diabetes prevalence (P for trend = 0.047), while zinc intake demonstrated a potential trend toward reduced diabetes risk (P for trend = 0.088). This association was similarly observed in the multivariate-adjusted model for the Composite Dietary Antioxidant Index (CDAI) in the female population (p = 0.046).

Conclusion

Intake of vitamin C was negatively associated with DM prevalence. Additionally, CDAI was found to reduce the risk of DM in the female population.

Fluoride Ingestion Induces Formation of Unusual Macromolecular Complexes in Gut Lumen Which Retard Absorption of Essential Minerals and Trace Elements by Chelation

This study investigates the impact of chronic fluoride exposure on the absorption of essential minerals in the gut and explores the mechanisms underlying mineral deficiencies due to fluoride ingestion. Male Wistar rats were randomly assigned to three groups: group 1 (G-1) served as the control (non-fluoride exposed), while group 2 (G-2) and group 3 (G-3) received human equivalent doses (HED) of fluoride (50 and 100 ppm ad libitum, corresponding to 5 and 10 ppm in humans, respectively) for 75 days. Serum fluoride concentrations were measured, and the levels of essential minerals and trace elements in blood and stool were analyzed using ICP-MS. X-ray diffraction (XRD) analysis was performed on stool samples to identify chemical compounds. The chemical compounds and macromolecular complexes containing fluoride and essential minerals were identified and quantified using Match3 software. Results indicated that the blood concentrations of essential minerals were significantly lower (p ≤ 0.05) in the fluoride-exposed groups compared to the control, while excretion of essential elements in stool was significantly higher (p ≤ 0.05) in the fluoride-administered groups. XRD analysis revealed the formation of unusual macromolecular chemical complexes in the stool of fluoride-treated groups, with the types and concentrations of these compounds increasing with higher fluoride doses. The study concludes that fluoride in the stomach chelates minerals, reducing their absorption, and induces the formation of unusual high molecular weight macromolecular chelation complexes, which alter the chemical species in the gut and further impair the absorption of essential minerals.

The interplay between oxidative stress, zinc, and metabolic dysfunction in polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is a functional endocrine disorder characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovarian morphology that has been associated with chronic disease and comorbidities including adverse metabolic and cardiac disorders. This review aims to evaluate the role of oxidative stress and zinc in the metabolic dysfunction observed in PCOS, with a focus on insulin resistance. Recent studies indicate that oxidative stress markers are elevated in PCOS and correlate with hyperandrogenemia, obesity, and insulin resistance. Zinc, an essential trace element, is crucial for metabolic processes, particularly in the pancreas for beta-cell function and glucagon secretion. Insufficient zinc levels have been linked to diabetes, obesity, and lipid metabolism disorders. This review aims to highlight the interplay between oxidative stress, zinc, and metabolic dysfunction in PCOS, suggesting that zinc supplementation could mitigate some metabolic and endocrine manifestations of PCOS.

Zinc: a potential star for regulating peritoneal fibrosis

Peritoneal dialysis (PD) is a commonly used renal replacement therapy for patients with end-stage renal disease (ESRD). During PD, the peritoneum (PM), a semi-permeable membrane, is exposed to nonbiocompatible PD solutions. Peritonitis can occur, leading to structural and functional PM disorders, resulting in peritoneal fibrosis and ultrafiltration failure, which are important reasons for patients with ESRD to discontinue PD. Increasing evidence suggests that oxidative stress (OS) plays a key role in the pathogenesis of peritoneal fibrosis. Furthermore, zinc deficiency is often present to a certain extent in patients undergoing PD. As an essential trace element, zinc is also an antioxidant, potentially playing an anti-OS role and slowing down peritoneal fibrosis progression. This study summarises and analyses recent research conducted by domestic and foreign scholars on the possible mechanisms through which zinc prevents peritoneal fibrosis.

Zinc Supplementation Reduces the Formation of Neutrophil Extracellular Traps by Decreasing the Expression of Peptidyl Arginine Deiminase 4

SCOPE

Neutrophils play a decisive role during the immediate defense against infections. However, as observed during rheumatoid arthritis, activated neutrophils can also cause tissue damage. Previous studies indicate that zinc supplementation may alter certain neutrophil functions. However, precise underlying mechanisms and possible effects of zinc deficiency remain incompletely understood. The objective of this study is to investigate the effects of changes in zinc status on formation of neutrophil extracellular traps (NETs) and other fundamental neutrophil functions.

METHODS AND RESULTS

Interleukin (IL)-17 and tumor necrosis factor (TNF)-α are used to simulate the inflammatory environment observed in autoimmune diseases. The study analyzes the impact of the zinc status on NETs release, using a fluorescence plate reader, and on the expression of peptidylarginine deiminase 4 (PAD4), S100A8/A9, and certain cytokines by PCR and western blot. These results show that zinc supplementation significantly reduces NETs formation and downregulates PAD4 protein expression. Zinc supplementation results in increased protein expression of interleukin-1 receptor antagonist (IL-1RA) and IL-8 in stimulated cells.

CONCLUSION

The results suggest that changes in extracellular zinc availability may influence the functions of neutrophils. Therefore, maintaining an appropriate zinc level is advisable for preserving innate immunity and to prevent hyper-activation of neutrophils.

Associations between multiple urinary metals and metabolic syndrome: Exploring the mediating role of liver function in Chinese community-dwelling elderly

BACKGROUND

Multiple metals exposure has been revealed to be related to metabolic syndrome (MetS). However, the associations and interactions between multiple metals exposure and MetS are remains controversial, and the potential mechanism of the above-mentioned is still unclear.

METHODS

The associations between urinary metals and the MetS were analyzed by multivariable logistic regression model and restricted cubic spline (RCS). Bayesian kernel machine regression (BKMR) model and quantile-based g-computation (qgcomp) were applied to explore the mixed exposure and interaction effect of metals. Mediation analysis was used to explore the role of liver function.

RESULTS

In the single metal model, multiple metals were significantly associated with MetS. RCS analysis further verified the associations between 8 metals and MetS. BKMR model and qgcomp showed that zinc (Zn), iron (Fe), and tellurium (Te) were the main factors affecting the overall effect. In addition, mediation analysis indicated that serum alanine aminotransferase (ALT) mediated 21.54% and 13.29% in the associations of vanadium (V) and Zn with the risk of MetS, respectively.

CONCLUSIONS

Elevated urinary concentration of Zn, V, Te, copper (Cu), molybdenum (Mo), and thallium (Tl) were related to the increased risk of MetS. Conversely, Fe and selenium (Se) may be protective factors for MetS in mixed exposure. Liver function may play a key role in the association of V and Zn exposure with MetS.

Synergistic impact of Chlorella vulgaris, zinc oxide- and/or selenium nanoparticles dietary supplementation on broiler's growth performance, antioxidant and blood biochemistry

The current study explored the influence of dietary supplementation of Chlorella vulgaris dried powder (CV) with zinc-oxide-nanoparticles (ZnO-NPs), and/or selenium-nanoparticles (Se-NPs) on broilers' growth, antioxidant capacity, immune status, histological responses, and gene expression of some related genes. Several 200 one-day-old Cobb-500 male chicks were distributed into 5 groups with four replicates each. In the 1st group, birds were fed the basal diet (BD). In the 2nd, 3rd, 4th, and 5th groups, birds received the BD supplemented with CV only, CV + ZnO-NPs, CV + Se-NPs, and CV + ZnO-NPs + Se-NPs, respectively. The CV dried powder, ZnO-NPs, and Se-NPs were added to the BD at a rate of 1 g, 40 mg, and 0.3 mg/kg diet, respectively. After 6 weeks of feeding, increases in final body weights (P < 0.05), body weight gain (P < 0.05), and feed intake (P < 0.05) were linked with improvements in FCR (P < 0.05) and intestinal morphometric indices (P < 0.05), and marked up-regulations of MYOS (P < 0.05), GHR (P < 0.05), and IGF (P < 0.05) genes were established. Additionally, distinct increases in antioxidant enzyme activities of SOD (P < 0.05), and GPX (P < 0.05) with increases in the mRNA copies of their genes were measured. Moreover, slight improvement in immunity indices, WBCs count (P > 0.05), and phagocytic and lysozyme activities (P > 0.05) were found. However, distinct increases in phagocytic index (P < 0.05) and up-regulations of IL-1β and TNF, and down-regulation of IL-10 mRNA levels were reported (P < 0.05). These findings were prominent in the case of the separate supplementation of CV with ZnO-NPs or Se-NPs confirming the synergistic mechanisms of CV with ZnO-NPs or Se-NPs. Thus, the synergetic supplementation of CV with ZnO-NPs, or Se-NPs in the broiler's diet could augment their growth and antioxidant response.

Metal ions in biomedically relevant macromolecular structures

Understanding the functions of metal ions in biological systems is crucial for many aspects of research, including deciphering their roles in diseases and potential therapeutic use. Structural information about the molecular or atomic details of these interactions, generated by methods like X-ray crystallography, cryo-electron microscopy, or nucleic magnetic resonance, frequently provides details that no other method can. As with any experimental method, they have inherent limitations that sometimes lead to an erroneous interpretation. This manuscript highlights different aspects of structural data available for metal-protein complexes. We examine the quality of modeling metal ion binding sites across different structure determination methods, where different kinds of errors stem from, and how they can impact correct interpretations and conclusions.

Bridging agro-science and human nutrition: zinc nanoparticles and biochar as catalysts for enhanced crop productivity and biofortification

The integration of zinc nanoparticles (Zn NPs) with biochar offers a transformative approach to sustainable agriculture by enhancing plant productivity and human nutrition. This combination improves soil health, optimizes nutrient uptake, and increases resilience to environmental stressors, leading to superior crop performance. Our literature review shows that combining Zn NPs with biochar significantly boosts the crop nutrient composition, including proteins, vitamins, sugars, and secondary metabolites. This enhancement improves the plant tolerance to environmental challenges, crop quality, and shelf life. This technique addresses the global issue of Zn deficiency by biofortifying food crops with increased Zn levels, such as mung beans, lettuce, tomatoes, wheat, maize, rice, citrus, apples, and microgreens. Additionally, Zn NPs and biochar improve soil properties by enhancing water retention, cation exchange capacity (CEC), and microbial activity, making soils more fertile and productive. The porous structure of biochar facilitates the slow and sustained release of Zn, ensuring its bioavailability over extended periods and reducing the need for frequent fertilizer applications. This synergy promotes sustainable agricultural practices and reduces the environmental footprint of the traditional farming methods. However, potential ecological risks such as biomagnification, nanoparticle accumulation, and toxicity require careful consideration. Comprehensive risk assessments and management strategies are essential to ensure that agricultural benefits do not compromise the environmental or human health. Future research should focus on sustainable practices for deploying Zn NPs in agriculture, balancing food security and ecological integrity and positioning this approach as a viable solution for nutrient-efficient and sustainable agriculture.

Foliar applications of zinc oxide nanoparticles and boric acid affect leaf oxidative metabolism and productivity in young pecan trees

Zinc and boron are nutrients that often suffer low bioavailability to pecan trees grown in calcareous soils whereas adequate supplies of these two elements is essential for commercial pecan production. Working with young pecan trees, we evaluated changes in oxidative metabolism, levels of bioactive compounds, yield components and foliar nutrient concentrations in response to foliar sprays (50 or 100 mg L-1) of zinc oxide nanoparticles (ZnO NPs) and boron (H3BO3). Four different treatment solutions were applied in a completely randomised design with six replications per treatment (24 trees in total). Zinc and B treatments were applied before pistil receptivity (3 weeks before anthesis) and at stem elongation stage 31, 39/60; flowering stage 69; fruit stages 7-75 and continued for a total of five applications at 14-day intervals. We evaluated enzyme activities (SOD, H2O2, CAT and GPx), AC, phenols, flavonoids, leaf area, chlorophyll, total anthocyanins and nut yield and quality (nut weight and % kernel). The mineral concentrations in the leaflets were also determined. The mineral concentrations (N, P, K, Ca, Mg, Fe, Cu, Mn, Ni, Zn and B) in the leaflets were also determined. Spraying ZnO NPs and B increased SOD activity, CA, chlorophyll concentration, mineral nutrients (N, K, Ca, Zn and B) and yield. However, reductions were observed for CAT activity, nut quality and concentrations of phenol, flavonoid, anthocyanin and Fe. Boron increased GPx activity and P concentration. These results demonstrate that spraying low doses (50 mg L-1) of ZnO NPs and B can help reduce oxidative stress and increase yield, nut quality and leaf concentrations of Zn and B in young cv. Wichita pecan trees established on a calcareous soil.

Zinc and Diabetes: A Connection between Micronutrient and Metabolism

Diabetes mellitus is a global health problem and a major contributor to mortality and morbidity. The management of this condition typically involves using oral antidiabetic medication, insulin, and appropriate dietary modifications, with a focus on macronutrient intake. However, several human studies have indicated that a deficiency in micronutrients, such as zinc, can be associated with insulin resistance as well as greater glucose intolerance. Zinc serves as a chemical messenger, acts as a cofactor to increase enzyme activity, and is involved in insulin formation, release, and storage. These diverse functions make zinc an important trace element for the regulation of blood glucose levels. Adequate zinc levels have also been shown to reduce the risk of developing diabetic complications. This review article explains the role of zinc in glucose metabolism and the effects of its inadequacy on the development, progression, and complications of diabetes mellitus. Furthermore, it describes the impact of zinc supplementation on preventing diabetes mellitus. The available information suggests that zinc has beneficial effects on the management of diabetic patients. Although additional large-scale randomized clinical trials are needed to establish zinc's clinical utility further, efforts should be made to increase awareness of its potential benefits on human health and disease.

Transgenerational impact of maternal zinc deficiency on offspring metabolic outcomes in Drosophila melanogaster

Maternal zinc deficiency significantly influences fetal development and long-term health outcomes, yet its transgenerational effects remain poorly understood. This study aims to investigate the transgenerational effects of maternal zinc deficiency on metabolic outcomes in Drosophila melanogaster. Zinc deficiency was induced in Drosophila by incorporating TPEN (N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine) into their diet. Offspring (F1 to F3) were maintained on a standard diet for subsequent analyses. Various metabolic markers, including glucose, trehalose, glycogen, and triglyceride levels, were assessed, and gene expression analyses were conducted to examine the molecular responses across generations. Significant reductions in locomotor performance in female F1 flies and increased body weight in the F2 generation were observed. Maternal zinc deficiency exhibited gender- and generation-specific impacts on metabolic markers. Notably, an adaptive response in the F3 generation included increased catalase activity and total antioxidant capacity, along with decreased malondialdehyde levels. Gene expression analyses revealed upregulation of DILP2 mRNA across generations and significant variations in PEPCK, SOD1, CAT, EGR, and UPD2 mRNA levels, demonstrating intricate responses to maternal zinc deficiency. This study provides a holistic understanding of the consequences of maternal zinc deficiency, emphasizing the complex interplay between zinc status and metabolic outcomes across generations in Drosophila. These findings lay the foundation for future research elucidating the underlying molecular mechanisms, with potential implications for humans. The insights gained contribute to informing targeted interventions aimed at optimizing offspring health in the context of maternal zinc deficiency.

Relationship Between Zinc, Selenium, and Magnesium Status and Markers of Metabolically Healthy and Unhealthy Obesity Phenotypes

Our objective was to investigate the relationship between zinc, selenium, and magnesium status and markers of metabolically healthy and unhealthy obesity phenotypes. This was a cross-sectional study with 140 women: metabolically healthy obese women (n = 35), metabolically unhealthy obese women (n = 28), and normal-weight women (n = 77). We have calculated the body mass index, waist-hip ratio, waist-height ratio and some adiposity indices. Additionally, we evaluated endocrine-metabolic parameters and estimated the dietary intake of energy, macronutrients, zinc, selenium, and magnesium. The mineral concentrations in plasma, erythrocytes, and urine were assessed. In obese patients, there was a significant decrease in dietary zinc, selenium, and magnesium intake per kilogram of body weight, as well as lower mineral concentrations in both plasma and erythrocytes. Additionally, these patients exhibited higher urinary mineral levels compared to the control group, regardless of whether they had healthy or unhealthy phenotypes. We observed a significant correlation between deficiencies in zinc, selenium, and magnesium and obesity-associated metabolic disorders, including dyslipidemias and redox status disturbances. This study highlights a connection between deficiencies in zinc, selenium, and magnesium and metabolic disorders linked to obesity, including dyslipidemias, alterations in redox status, and thyroid hormonal dysfunction.

Zinc-associated phospholipid metabolic alterations and their impacts on ALT levels in workers

Zinc (Zn) is an essential trace element that is required for various biological functions, but excessive exposure to Zn is associated with many disorders and even diseases. However, the health effects and underlying mechanisms of long-term and high concentration exposure of Zn remain to be unclear. In the present study, we investigated the association between occupational exposure to Zn and liver function indicators (like alanine aminotransferase (ALT)) in workers. We found a positive association between Zn exposure and ALT level in workers. Workers having higher blood Zn (7735.65 (1159.15) μg/L) shows a 30.4 % increase in ALT level compared to those with lower blood Zn (5969.30 (989.26) μg/L). Furthermore, we explored the effects of phospholipids (PLs) and their metabolism on ALT level and discovered that Zn exposure in workers was associated with changes in PL levels and metabolism, which had further effects on increased ALT levels in workers. The study provides insights into the relationship between occupational Zn exposure and liver function, highlights the risk of long-term exposure to high concentrations of Zn, and paves the way for understanding the underlying mechanisms of Zn exposure on human health.

High levels of high-density lipoprotein cholesterol may increase the risk of diabetic kidney disease in patients with type 2 diabetes

Studies have indicated that low high-density lipoprotein cholesterol (HDL-C) level is an important risk factor for diabetic kidney disease (DKD) in patients with type 2 diabetes (T2D). However, whether higher HDL-C levels decrease the risk of developing DKD remains unclear. This study aimed to clarify the relationship between HDL-C levels and DKD risk in individuals with T2D in China. In total, 936 patients with T2D were divided into DKD and non-DKD groups. The association between HDL-C levels and DKD risk was evaluated using logistic regression analysis and restricted cubic spline curves adjusted for potential confounders. Threshold effect analysis of HDL-C for DKD risk was also performed. Higher HDL-C levels did not consistently decrease the DKD risk. Furthermore, a nonlinear association with threshold interval effects between HDL-C levels and the incidence of DKD was observed. Patients with HDL-C ≤ 0.94 mmol/L or HDL-C > 1.54 mmol/L had significantly higher DKD risk after adjusting for confounding factors. Interestingly, the association between high HDL-C levels and increased DKD risk was more significant in women. A U-shaped association between HDL-C levels and DKD risk was observed; therefore, low and high HDL-C levels may increase the DKD risk in patients with T2D.

Enhancing Tranexamic Acid Penetration through AQP-3 Protein Triggering via ZIF-8 Encapsulation for Melasma and Rosacea Therapy

The systemic use of tranexamic acid (TA) as an oral drug can bring adverse reactions, while intradermal injection leads to pain and a risk of infection. Moreover, it is difficult for highly hydrophilic TA to penetrate the skin barrier that contains lots of hydrophobic lipid compounds, which poses enormous restrictions on its topical application. Current transdermal TA delivery strategies are suffering from low drug load rates, plus their synthesis complexity, time-consumption, etc. adding to the difficulty of TA topical application in clinical therapeutics. To increase the penetration of TA, a novel approach using TA-loaded ZIF-8 (TA@ZIF-8) is developed. The encapsulation efficiency of TA@ZIF-8 reaches ≈25% through physical adsorption and chemical bonding of TA indicates by theoretical simulation and the improved TA penetration is elevated through activating the aquaporin-3 (AQP-3) protein. Additionally, in vivo and in vitro experiments demonstrate the preponderance of TA@ZIF-8 for penetration ability and the advantages in intracellular uptake, minor cytotoxicity, and inhibition of melanogenesis and inflammatory factors. Moreover, clinical trials demonstrate the safety and efficacy of TA@ZIF-8 in the treatment of melasma and rosacea. This work presents a potential topical application of TA, free from the safety concerns associated with systemic drug administration.

Association Between Circulating Zinc Levels and Risk Factors of Metabolic Syndrome: Insights from a Bi-directional Mendelian Randomization Analysis and Cross-Sectional Study

Previous studies on the relationship between zinc and metabolic syndrome (MetS) have yielded inconsistent results. This comprehensive study aimed to elaborately explore the impact of zinc on MetS risk factors. The bi-directional Mendelian randomization (MR) analyses were performed to estimate the causal relationship between zinc and MetS risk factors. Additionally, a retrospective cross-sectional study incorporated 4389 subjects to provide a broader perspective in conjunction with the MR analyses. In the MR analyses, genetically instrumented zinc was positively associated with five of the MetS components in Europeans, including BMI, FBG, HbA1c, TC, and LDL-c (β (95%CI) = 0.023 (0.019-0.027), 0.019 (0.013-0.025), 0.041 (0.022-0.060), 0.027 (0.013-0.042), and 0.018 (0.010-0.026), respectively). In the cross-sectional study, higher concentration of zinc was strongly associated with increased BMI, LDL-c, and UA (β (95%CI) = 0.040 (0.010-0.085), 0.026 (0.018-0.035), and 1.529 (0.614-2.445), respectively). Moreover, these unfavorable associations were more obvious in women compared to men, with a borderline significant interaction effect for BMI (P=0.051). Our study showed that higher blood concentration of zinc, an essential trace element, was associated with unfavorable changes of the component metabolic risk factors of MetS, especially with BMI and LDL-c. Notably, these associations seemed to be more pronounced in women rather than in men. Further studies are warranted to elucidate the role of zinc status in the underlying mechanisms of MetS.

Association of Blood Trace Elements Levels with Cardiovascular Disease in US Adults: a Cross-Sectional Study from the National Health and Nutrition Examination Survey 2011-2016

We aimed to explore the overall association between trace elements and cardiovascular disease (CVD) and its types in humans. A total of 5101 participants' blood samples from the 2011-2016 National Health and Nutrition Examination Survey were included. Biochemical data were collected from laboratory tests conducted at mobile screening centers. After assessing linearity, weighted logistic regression estimated the association between trace elements and various CVD types. Weighted quantile sum (WQS) regression and quantile-based g-computation (Qgcomp) evaluated the overall relationship between biological trace elements and CVD types. After fully adjusting for confounding factors, the odds ratios of overall CVD morbidity corresponding to the second, third, and fourth quartiles of higher selenium (Se) concentration were 0.711 (95% CI, 0.529-0.956, p = 0.024), 0.734 (95% CI, 0.546-0.987, p = 0.041), and 0.738 (95% CI, 0.554-0.983, p = 0.038), respectively. Moreover, an increase in the concentration of copper (Cu) was associated with an increased risk of stroke (95% CI, 1.012-1.094, p = 0.01), heart failure (95% CI, 1.001-1.095, p = 0.046), and heart attack (95% CI, 1.001-1.083, p = 0.046). As the concentration of trace elements in the body increased, there was a significant positive association between Cu and CVD prevalence. On the other hand, Se and zinc were negatively associated with CVD prevalence. A nonlinear relationship between Se and CVD was found, and an appropriate Se intake may reduce the risk of CVD. Cu levels positively correlated with CVD risk. However, prospective cohort studies are warranted to confirm the causal effects of the micronutrients on CVD and its types.

Assessment of the Impact of Trace Essential Metals on Cancer Development

This study examines the impact of zinc, copper, cobalt, iron, and manganese on cancer development, considering their dual roles as potential promoters or inhibitors within tumorigenesis. A comprehensive analysis of existing literature and experimental data is conducted to elucidate the intricate relationship between these trace elements and cancer progression. The findings highlight the multifaceted effects of zinc, copper, cobalt, iron, and manganese on various aspects of cancer development, including cell proliferation, angiogenesis, and metastasis. Understanding the nuanced interactions between these trace elements and cancer could offer crucial insights into tumorigenesis mechanisms and facilitate the identification of novel biomarkers and therapeutic targets for cancer prevention and treatment strategies. This research underscores the importance of considering the roles of essential trace elements in cancer biology and may ultimately contribute to advancements in precision medicine approaches for combating cancer.

Placental Expression of Glucose and Zinc Transporters in Women with Gestational Diabetes

Background/Objectives: Gestational diabetes (GDM) is a metabolic disorder with altered glucose levels diagnosed in pregnant women. The pathogenesis of GDM is not fully known, but it is thought to be caused by impaired insulin production and insulin resistance induced by diabetogenic factors. The placenta may play an important role in the development of GDM. Glucose transporters (GLUTs) are responsible for the delivery of glucose into the foetal circulation. Placental zinc transporters regulate insulin and glucagon secretion, as well as gluconeogenesis and glycolysis. The aim of this study was to investigate the placental expression of GLUT3, GLUT4, GLUT7 and SLC30A8 in women with GDM. Furthermore, we evaluated whether the expression profiles of these transporters were correlated with clinical parameters. Methods: This study included 26 patients with GDM and 28 patients with normal glucose tolerance (NGT). Results: The placental expression of GLUT3 was significantly reduced in the GDM group, while the placental expression of GLUT4, GLUT7 and SLC30A8 was significantly upregulated in the GDM group. GLUT3 expression correlated significantly with body mass index (BMI) increase during pregnancy and body mass increase during pregnancy, while GLUT4 expression correlated negatively with BMI at birth. Conclusions: These results suggest the involvement of GLUT3 and GLUT4, GLUT7 and SLC30A8 in the pathogenesis of GDM.