Effects of zinc supplementation on inflammatory biomarkers and oxidative stress in adults: A systematic review and meta-analysis of randomized controlled trials

Anti-inflammatory effects of 64Zn-aspartate is accompanied by cognitive improvements in rats with Aβ1-40-induced alzheimer disease

Alzheimer disease (AD) is a debilitating progressive dementia, whose pathophysiology is not fully understood. Chronic inflammation is now widely accepted as one of the key features of AD pathogenesis. Because of this, anti-inflammatory preparations are considered as putative disease modifying agents. A new compound of zinc aspartate with enriched light atoms 64Zn (64Zn-asp) was evaluated as a possible anti-AD agent using Aβ1-40-induced AD model. Intrahippocampal Aβ1-40 injection resulted in pronounced neuroinflammation, as was evidenced by increased phagocytic activity, augmented reactive oxygen species generation, and up-regulated CD86 and CD206 expression by microglia. In rats with Aβ1-40-induced AD, persistent systemic inflammation was also registered, as was ascertained by significantly increased white blood cell-based inflammatory indices and development of anemia of inflammation. Neuro- and systemic inflammation in rats was accompanied by hippocampal dopamine neuron loss, as well as by impairment of short-term and remote spatial memory and cognitive flexibility. Intravenous 64Zn-asp administration rats with AD was associated with returning all microglia indicators to normal range. All aforementioned features of systemic inflammation were not observed in these animals. Anti-inflammatory 64Zn-asp effect was strongly correlated with improvement of short-term spatial memory and cognitive flexibility, and moderately-with betterment of remote spatial memory. These results demonstrated that i.v. 64Zn-asp administration could reverse the inflammatory and, as a result, cognitive effects of intra-hippocampal Aβ1-40 in rats. Therefore, its use may be a viable approach in the complex therapeutic strategy for AD.

Interaction between dietary selenium intake and age on severe headache or migraine in the United States: a population-based study

Background

Studies have shown that an antioxidant diet is a protective factor against migraine. However, the association between selenium, an important antioxidant consumed from the diet, and migraine has received little attention. The aim of this study was to explore the relationship between dietary selenium intake with migraine, with particular interest in age differences.

Methods

This study based on cross-sectional data from people who took part in the National Health and Nutrition Examination Survey (NHANES) between 1999 and 2004. The multiple logistic regression model was applied to examine the association between selenium intake and migraine, and subgroup analyses were performed. Non-linear associations were explored with restricted cubic spline (RCS) models.

Results

The study included a total of 9,849 adults aged 20 years and older. Compared with individuals with lowest selenium intake Q1 (≤59.4 ug/day), the adjusted OR values for selenium intake and migraine in Q2 (59.41-82.70 ug/day), Q3 (82.71-106 ug/day), Q4 (106.01-143.16 ug/day), and Q5 (≥143.17 ug/day) were 0.82 (95% CI: 0.64-1.05), 0.99 (95% CI: 0.77-1.26), 0.74 (95% CI: 0.54-0.99), and 0.68 (95% CI: 0.48-0.97), respectively. Sensitivity analyses showed a robust association between them. Our findings also suggested an interaction between age and selenium intake (p for interaction = 0.04). Additionally, the relationship between selenium intake and migraine in adults with 20-50 years was L-shaped. The OR of developing migraine was 0.97 (95% CI: 0.94-0.98) in individuals with selenium intake ≥101.9 ug/day in adults with 20-50 years.

Conclusion

A higher dietary selenium intake is significantly associated with a decreased prevalence of migraine, and age can modify the association between them. Therefore, the present study indicate that an appropriate intake of selenium-rich foods in adults aged 20-50 years may prevent migraines.

Elevated Serum Copper, Zinc, Selenium, and Lowered α-Klotho Associations: Findings from NHANES 2011-2016 Dataset

The α-Klotho is crucial for human health and longevity. However, the relationship between trace elements and α-Klotho levels needs further investigation. We aimed to explore the relationship between serum levels of selenium (Se), copper (Cu), and zinc (Zn), and serum α-Klotho levels. We analyzed 2138 samples from the 2011-2016 National Health and Nutrition Examination Survey, and the weighted linear regression, WQS, and qgcomp models were utilized to evaluate the effects of these elements on serum α-Klotho levels, individually and combined. A negative correlation was observed between serum Cu concentration and serum α-Klotho levels (β =  - 0.128, 95% CI - 0.196, - 0.059), with each increase in Cu concentration grade showing a gradual decrease in serum α-Klotho levels (Ptrend = 0.002). The WQS model exhibited a negative correlation between the combined effect of Se, Cu, and Zn and serum α-Klotho levels (β =  - 0.035, 95%CI - 0.060, - 0.010), consistently in males (β =  - 0.038 (- 0.059, - 0.017)) and in the 40-49 age group (β =  - 0.059, 95% CI - 0.119, - 0.012). The qgcomp model mirrored these findings, showing a negative correlation in the combined effect index of Se, Cu, and Zn with serum α-Klotho levels (β =  - 0.027, 95% CI - 0.047, - 0.006), consistent in females (β =  - 0.032, 95% CI - 0.061, - 0.004) and in individuals with BMI ≥ 25 (β =  - 0.030, 95% CI - 0.054, - 0.006), and in the 40-49 age group (β =  - 0.047, 95% CI - 0.088, - 0.006). Elevated serum Cu levels may be associated with lower serum α-Klotho levels. The combined effect of serum Se, Cu, and Zn shows a negative correlation with serum α-Klotho levels, with Cu contributing the most. Our findings provide significant insights into assessing the role of trace nutrients in maintaining human health.

Trace elements and metal nanoparticles: mechanistic approaches to mitigating chemotherapy-induced toxicity-a review of literature evidence

Anticancer chemotherapy (ACT) remains a cornerstone in cancer treatment, despite significant advances in pharmacology over recent decades. However, its associated side effect toxicity continues to pose a major concern for both oncology clinicians and patients, significantly impacting treatment protocols and patient quality of life. Current clinical strategies to mitigate ACT-induced toxicity have proven largely unsatisfactory, leaving a critical unmet need to block toxicity mechanisms without diminishing ACT's therapeutic efficacy. This review aims to document the molecular mechanisms underlying ACT toxicity and highlight research efforts exploring the protective effects of trace elements (TEs) and their nanoparticles (NPs) against these mechanisms. Our literature review reveals that the primary driver of ACT toxicity is redox imbalance, which triggers oxidative inflammation, apoptosis, endoplasmic reticulum stress, mitochondrial dysfunction, autophagy, and dysregulation of signaling pathways such as PI3K/mTOR/Akt. Studies suggest that TEs, including zinc, selenium, boron, manganese, and molybdenum, and their NPs, can potentially counteract ACT-induced toxicity by inhibiting oxidative stress-mediated pathways, including NF-κB/TLR4/MAPK/NLRP3, STAT-3/NLRP3, Bcl-2/Bid/p53/caspases, and LC3/Beclin-1/CHOP/ATG6, while also upregulating protective signaling pathways like Sirt1/PPAR-γ/PGC-1α/FOXO-3 and Nrf2/HO-1/ARE. However, evidence regarding the roles of lncRNA and the Wnt/β-catenin pathway in ACT toxicity remains inconsistent, and the impact of TEs and NPs on ACT efficacy is not fully understood. Further research is needed to confirm the protective effects of TEs and their NPs against ACT toxicity in cancer patients. In summary, TEs and their NPs present a promising avenue as adjuvant agents for preventing non-target organ toxicity induced by ACT.

Appraising the Role of Circulating Concentrations of Micronutrients in Hypertension: A Two-sample, Multivariable Mendelian Randomization Study

Background

Hypertension poses a significant global health challenge, warranting exploration of novel preventive measures. This study aimed to investigate the role of circulating concentrations of various micronutrients in hypertension using a Mendelian randomization (MR) approach.

Methods

Data on hypertension were obtained from FinnGen, comprising 55,917 cases and 162,837 controls of European ancestry. Fifteen micronutrients were evaluated and selected based on genome-wide association studies (GWAS) data. Instrumental single nucleotide polymorphisms (SNPs) were chosen according to strict criteria. Univariable Mendelian randomization (UVMR) analysis was conducted using the inverse variance weighted (IVW) method, supplemented by sensitivity analyses. Multivariate Mendelian randomization (MVMR) analysis was performed to assess interactions between micronutrients.

Results

In UVMR analysis, the IVW method revealed a potential influence of copper (OR = 1.052, 95% CI: 1.006-1.099, P = 0.025) and zinc (OR = 1.083, 95% CI: 1.007-1.165, P = 0.031) on hypertension. Sensitivity analyses supported these findings. MVMR analysis confirmed a direct positive effect of zinc on hypertension (OR = 1.087, 95% CI: 1.026-1.151, P = 0.005), while adjusting for zinc attenuated the effect of copper on hypertension (OR = 1.026, 95% CI: 0.987-1.066, P = 0.193).

Conclusion

Circulating zinc levels may be a potential risk factor for hypertension, while the association with other micronutrients remains inconclusive. These findings suggest that reducing zinc intake within a healthy range may help lower hypertension risk. Future research should further explore the role of zinc and nonlinear associations for a more comprehensive understanding.

The Association of Dietary Micronutrient Intake and Systemic Inflammation among Patients with Type 2 Diabetes: A Cross-Sectional Study

Inflammation contributes to the pathogenesis of type 2 diabetes (T2DM). This study sought to document how the systemic biomarkers of inflammation varied based on food choices among patients with T2DM. This cross-sectional study enrolled ambulatory patients with T2DM. Demographic and clinical information was collected. Five drops of fingerstick blood were collected using an absorbent paper device (HemaSpot HFR). C-reactive protein (CRP), serum amyloid A protein (SAA), and fibrinogen were measured using a Luminex assay. Patient-generated 7-day food diaries were analyzed using a validated food processor software. Data were analyzed by Pearson's correlation tests, linear regression and logistic regression with the significance level set at 0.05. Among the 71 participants, 43 (60.6%) were females. The average age and duration of T2DM were 64.1 ± 10.3 and 15.8 ± 9.1 years, respectively. In a simple linear regression run with selected micronutrients, iron [F (1, 53) = 5.319, p < 0.05, adj. R2 = 0.074] significantly predicted plasma CRP. This significance was lost with multiple linear regressions including age, gender, BMI, T2DM duration, T2DM complications, glycohemoglobin A1c (HbA1c) and other micronutrients. The average intake of most micronutrients by the participants was below the recommended daily intake. A higher intake of iron-rich foods was associated with higher levels of systemic inflammation in a simple linear regression model, but the association was not present after adjusting for patient factors like age, gender, BMI and T2DM-related variables. This relationship needs to be explored further given the key role of inflammation in the pathogenesis of T2DM and its associated complications.

Zinc Supplementation in Individuals with Prediabetes and type 2 Diabetes: a GRADE-Assessed Systematic Review and Dose-Response Meta-analysis

Zinc supplementation has therapeutic effects on cardiovascular disease (CVD) risk factors, including dyslipidemia, hyperglycemia, and inflammation as the main contributors to CVD pathogenesis. Since CVD is a major cause of mortality among people with type 2 diabetes mellitus (T2DM), this study aimed to overview the potential effects of zinc supplementation on CVD risk factors in T2DM patients. To determine appropriate randomized clinical trials (RCTs) investigating the effects of zinc supplementation on CVD risk factors, electronic sources including PubMed, Web of Science, and Scopus were systematically searched until January 2023. The heterogeneity of trials was checked using the I2 statistic. According to the heterogeneity tests, random-effects models were estimated, and pooled data were defined as the weighted mean difference (WMD) with a 95% confidence interval (CI). Of the 4004 initial records, 23 studies that met inclusion criteria were analyzed in this meta-analysis. The pooled findings indicated the significant lowering effects of zinc supplementation on triglycerides (TG), total cholesterol (TC), fasting blood glucose (FBG), hemoglobin A1C (HbA1C), and C-reactive protein (CRP), while high-density cholesterol (HDL) concentrations showed an elevation after zinc supplementation. In addition to statistical significance, the effect of zinc supplementation on most of the variables was clinically significant; however, the quality of evidence in the included studies is regarded as low or very low for most variables. Our study demonstrated that zinc supplementation has beneficial effects on glycemic control markers, lipid profile, and CRP levels as a classic marker of inflammation in T2DM. Due to the high degree of heterogeneity between studies and the low rate of quality in them, further well-designed studies are necessitated to strengthen our findings.

Antioxidant Minerals Modified the Association between Iron and Type 2 Diabetes in a Chinese Population

Inconsistent findings exist regarding the relationship between heme iron intake and type 2 diabetes (T2D) among Western and Eastern populations. Easterners tend to consume a plant-based diet which is abundant in antioxidant minerals. To examine the hypothesis that antioxidant mineral may modify the relationship between iron and T2D, we performed a case-control study by measuring the serum mineral levels in 2198 Chinese subjects. A total of 2113 T2D patients and 2458 controls were invited; 502 T2D patients and 1696 controls were finally analyzed. In the total population, high serum iron showed a positive association with T2D odds (odds ratio [OR] = 1.27 [1.04, 1.55]); high magnesium (OR = 0.18 [0.14, 0.22]), copper (OR = 0.27 [0.21, 0.33]), zinc (OR = 0.37 [0.30, 0.46]), chromium (OR = 0.61 [0.50, 0.74]), or selenium concentrations (OR = 0.39 [0.31, 0.48]) were inversely associated with T2D odds. In contrast, in individuals with higher magnesium (>2673.2 µg/dL), zinc (>136.7 µg/dL), copper (>132.1 µg/dL), chromium (>14.0 µg/dL), or selenium concentrations (>16.8 µg/dL), serum iron displayed no association with T2D (p > 0.05). Serum copper and magnesium were significant modifiers of the association between iron and T2D in individuals with different physiological status (p < 0.05). Our findings support the idea that consuming a diet rich in antioxidant minerals is an effective approach for preventing T2D.

Mitochondrial Glutathione in Cellular Redox Homeostasis and Disease Manifestation

Mitochondria are critical for providing energy to maintain cell viability. Oxidative phosphorylation involves the transfer of electrons from energy substrates to oxygen to produce adenosine triphosphate. Mitochondria also regulate cell proliferation, metastasis, and deterioration. The flow of electrons in the mitochondrial respiratory chain generates reactive oxygen species (ROS), which are harmful to cells at high levels. Oxidative stress caused by ROS accumulation has been associated with an increased risk of cancer, and cardiovascular and liver diseases. Glutathione (GSH) is an abundant cellular antioxidant that is primarily synthesized in the cytoplasm and delivered to the mitochondria. Mitochondrial glutathione (mGSH) metabolizes hydrogen peroxide within the mitochondria. A long-term imbalance in the ratio of mitochondrial ROS to mGSH can cause cell dysfunction, apoptosis, necroptosis, and ferroptosis, which may lead to disease. This study aimed to review the physiological functions, anabolism, variations in organ tissue accumulation, and delivery of GSH to the mitochondria and the relationships between mGSH levels, the GSH/GSH disulfide (GSSG) ratio, programmed cell death, and ferroptosis. We also discuss diseases caused by mGSH deficiency and related therapeutics.

The Role of Zinc Supplementation in Alleviating Inflammatory Biomarkers in Patients Undergoing Hemodialysis: A Randomized Placebo Controlled, Crossover Trial

Background

Chronic kidney disease (CKD), which progresses to end-stage renal disease (ESRD) and requires maintenance hemodialysis (MHD), is a global health issue. Inflammation in MHD patients is associated with increased mortality and cardiovascular events. Zinc, essential for immune function and possessing anti-inflammatory properties, is frequently deficient in these patients and could potentially help mitigate inflammation.

Objectives

This study aims to assess the impact of zinc supplementation on inflammatory biomarkers, specifically (CRP) and the neutrophil-to-lymphocyte ratio (NLR), in MHD patients.

Methods

In a double-blind, randomized controlled crossover trial conducted at Labafinejad Hospital, Tehran, MHD patients with zinc deficiency were initially allocated to either a zinc supplementation group or a placebo group. After 30 days, the groups were crossed over, with patients initially receiving zinc now receiving a placebo and vice versa. The primary outcome was changes in serum zinc levels, while secondary outcomes focused on CRP and NLR levels.

Results

Significant changes in serum zinc levels were observed in both groups from baseline to Month 2 (drug-placebo group: Mean change -15.9±10.33 µg/dL, P < 0.05; placebo-drug group: Mean change -14.70 ± 12.58 µg/dL, P < 0.05). A significant initial reduction in CRP levels at Month 1 (P = 0.045) was not sustained at Month 2 (P = 0.812). No statistically significant changes in NLR were noted. Improvements in quality of life, including reductions in muscle pain and skin dryness, were significant in the drug-placebo group (P < 0.05).

Conclusions

Zinc supplementation in MHD patients significantly improved serum zinc levels and initially reduced CRP levels, highlighting its potential role in managing inflammation. Although the impact on NLR was not significant, overall patient outcomes and quality of life showed promising improvements.

Effects of Zinc Supplementation on Inflammatory and Cognitive Parameters in Middle-Aged Women with Overweight or Obesity

Obesity has been linked to cognitive decline and adverse effects on brain health. Zinc (Zn) is a mineral with important metabolic functions that can modulate obesity-related neurological impairment. Thus, the present study aimed to evaluate the effects of 12 weeks of Zn supplementation on the inflammatory profile, cognitive function, and mood of overweight or obese women through a double-blind, placebo-controlled study. The study included 42 women aged between 40 and 60, randomly divided into two groups: Zn supplementation (30 mg/day) or placebo for 12 weeks. Data regarding sociodemographic, anthropometric, dietary, and physical activity were collected. Mini-mental state examination (MMSE), verbal fluency test, clock drawing test, and Stroop test were performed. Anxiety and depression symptoms were assessed using the Beck anxiety inventory and the BDI-II, respectively. Saliva samples were collected to evaluate IL-1β, IL-6, TNF-α, insulin, nitrite, and Zn levels. Of the 42 participants (mean age 49.58 ± 6.46 years), 32 were included in the study analyses. Changes in body weight and macronutrient consumption were not different between placebo and Zn supplementation groups. Cognitive scores on the MMSE and Stroop tests were higher in the Zn supplementation group than in the placebo group. Salivary levels of IL-1b and Zn increased in the Zn group compared to placebo. There was no significant change in the adjusted means of the BDI-II and BECK scores between the zinc vs. placebo groups. Twelve weeks of Zn supplementation was able to partially improve the cognitive scores assessed in overweight or obese women, regardless of weight loss. These findings suggest that Zn supplementation can be considered an adjunct strategy to enhance cognitive health in overweight or obese women.

Zinc supplementation and cardiovascular disease risk factors: A GRADE-assessed systematic review and dose-response meta-analysis

BACKGROUND AND OBJECTIVE

A deficit in zinc has been related to a higher probability of developing cardiovascular diseases (CVDs). The anti-inflammatory and anti-oxidative capabilities of zinc may have a wide range of therapeutic impacts on CVDs. We conducted a comprehensive systematic review and meta-analysis of the possible impacts that zinc supplementation may have on the risk factors associated with CVDs.

METHODS

To identify eligible randomized clinical trials (RCTs) evaluating the effects of zinc supplementation on CVDs risk factors, electronic databases including PubMed, Web of Science, and Scopus were systematically searched up to January 2023. The heterogeneity of trials was checked using the I² statistic. According to the heterogeneity tests, random effects models were estimated and pooled data were defined as the weighted mean difference (WMD) with a 95% confidence interval (CI).

RESULTS

Of 23165 initial records, 75 studies that met inclusion criteria were analyzed in this meta-analysis. The pooled findings indicated the significant lowering effects of zinc supplementation on triglycerides (TG), total cholesterol (TC), fasting blood glucose (FBG), Hemoglobin A1C (HbA1C), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), C-reactive protein (CRP), interleukin-6 (IL-6), Tumor necrosis factor-α (TNF-α), nitric oxide (NO), malondialdehyde (MDA), total antioxidant capacity (TAC), and glutathione (GSH), with no noticeable effects on low-density lipoprotein (LDL), high-density lipoprotein (HDL), insulin, systolic blood pressure (SBP), diastolic blood pressure (DBP), aspartate transaminase (AST), and Alanine aminotransferase (ALT).

CONCLUSION

Overall, zinc supplementation may boost recognized coronary risk factors that contribute to the development of CVDs. Future research should be conducted to bolster our results.

Effects of Zinc on the Right Cardiovascular Circuit in Long-Term Hypobaric Hypoxia in Wistar Rats

Hypobaric hypoxia under chromic conditions triggers hypoxic pulmonary vasoconstriction (HPV) and right ventricular hypertrophy (RVH). The role of zinc (Zn) under hypoxia is controversial and remains unclear. We evaluated the effect of Zn supplementation in prolonged hypobaric hypoxia on HIF2α/MTF-1/MT/ZIP12/PKCε pathway in the lung and RVH. Wistar rats were exposed to hypobaric hypoxia for 30 days and randomly allocated into three groups: chronic hypoxia (CH); intermittent hypoxia (2 days hypoxia/2 days normoxia; CIH); and normoxia (sea level control; NX). Each group was subdivided (n = 8) to receive either 1% Zn sulfate solution (z) or saline (s) intraperitoneally. Body weight, hemoglobin, and RVH were measured. Zn levels were evaluated in plasma and lung tissue. Additionally, the lipid peroxidation levels, HIF2α/MTF-1/MT/ZIP12/PKCε protein expression and pulmonary artery remodeling were measured in the lung. The CIH and CH groups showed decreased plasma Zn and body weight and increased hemoglobin, RVH, and vascular remodeling; the CH group also showed increased lipid peroxidation. Zn administration under hypobaric hypoxia upregulated the HIF2α/MTF-1/MT/ZIP12/PKCε pathway and increased RVH in the intermittent zinc group. Under intermittent hypobaric hypoxia, Zn dysregulation could participate in RVH development through alterations in the pulmonary HIF2α/MTF1/MT/ZIP12/PKCε pathway.

Effect of zinc supplementation in the management of type 2 diabetes: A grading of recommendations assessment, development, and evaluation-assessed, dose-response meta-analysis of randomized controlled trials

The question of whether zinc supplementation may improve cardio-metabolic health in patients with type 2 diabetes mellitus (T2DM) remains controversial and require further evaluation. This study aimed to summarize the effectiveness of oral zinc supplementation in improving cardio-metabolic risk markers in people with T2DM. We searched PubMed, Scopus, and Web of Science from inception to April 2023, for randomized controlled trials (RCTs). RCTs of type 2 diabetic adults (aged ≥18 years) comparing zinc supplementation with placebo were included. We excluded studies if not randomized, involved co-supplementation, and were conducted in children or pregnant women. Glycemic indices, lipid profiles, blood pressure, anthropometric measure, c-reactive protein (CRP), creatinine, and serum zinc were extracted. Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methods. We used a random-effect model to perform the dose-response analysis. Effect sizes were presented as mean difference (MD) and 95% confidence interval (CI). 22 studies (n = 1442 participants) were included. The certainty of the evidence was rated as moderate to high. Zinc supplementation significantly reduced glycemic indices: including two-hour postprandial glucose (2hpp) (mean difference (MD): -34.34 mg/dl; 95%CI: -51.61∼ -17.07), fast blood sugar (FBS) (MD: -23.32 mg/dl; 95% CI: -33.81∼ -12.83), and hemoglobin A1c (HbA1c) (MD: -0.47; 95% CI: -0.71∼ -0.23). Zinc had a favorable effect on lipid profiles low-density lipoprotein (LDL) (MD: -10.76 mg/dl; CI: -17.79∼-3.73), triglyceride (TG) (MD: -18.23 mg/dl; CI: -32.81∼-3.65), total cholesterol (TC) (MD: -12.74 mg/dl; CI: -21.68∼-3.80), VLDL (MD: -5.39 mg/dl; CI: -7.35∼-3.43) and high-density lipoprotein (HDL) (MD: 4.04 mg/dl; CI: 0.96 ∼ 7.12). Systolic blood pressure (SBP) (MD): -3.64 mmHg; 95% CI: -6.77∼ -0.52), weight (MD: 1.00 kg; 95% CI: 0.34∼1.66), CRP (MD: -3.37 mg/l, 95% CI: -4.05∼ -2.70), and serum zinc (MD: 15.38 µg/dl; 95% CI: 10.74∼ 20.02) changed to a statistically significant extent with zinc supplementation. There was also a linear association between additional 10 mg/d zinc treatment with FBS, HbA1c, HDL, LDL, TG, TC, and serum zinc. A non-linear dose-response gradient was seen for FBS, HDL, and SBP (p < 0.05). Egger's test showed no substantial publication bias. Our findings strongly suggest a potential beneficial effect of zinc supplementation on type 2 diabetic patients. Further high-quality research is needed to determine the optimal form, dosage, and duration of zinc supplementation for this population.

Quercetin inhibits hepatotoxic effects by reducing trimethylamine-N-oxide formation in C57BL/6J mice fed with a high L-carnitine diet

L-Carnitine can be metabolized to trimethylamine (TMA) by gut microbiota and further converted into trimethylamine N-oxide (TMAO) in the liver, leading to liver damage. This study aimed to investigate the protective effect of quercetin against high L-carnitine-induced liver toxicity in mice. 3% L-carnitine drinking water was used to feed mice in this study. The formation of TMAO in the blood circulation of the tested mice was down-regulated following quercetin treatment. Administration of quercetin could also effectively antagonize the liver injury caused by high L-carnitine intake, which was proved by the decreased serum AST and ALT activities and the reduced levels of inflammatory liver cytokines (IL-1, IL-6, TNF-α, and TNF-β). Moreover, quercetin exhibited a rebalancing effect on dyslipidemia (TC, TG, HDL, and LDL) and antioxidant abilities (SOD, GSH-Px, MDA, and RAHFR) in L-carnitine-treated mice. The results of hepatic H&E and Oil Red O staining further verified the liver injury of high L-carnitine-treated mice and the protective effects of quercetin. These findings suggested that quercetin could attenuate the hepatotoxic effects of the mice fed with a high L-carnitine diet via inhibiting the circulating TMAO formation.

The Serum Oxidative Stress Biomarkers and Selenium Levels in a Group of Migraine Patients Compared with Healthy Controls: a Case-Control Study

Migraine is one of the most common neurological disorders associated with recurrent attacks of moderate to severe headache. Oxidative stress may play an important role in migraine pathogenesis. This study aimed to measure and compare the serum levels of Selenium, total antioxidant capacity (TAC), and malondialdehyde) MDA (in migraine patients and healthy individuals. This case-control study was performed on 31 migraine patients and 30 age and gender-matched healthy controls. The severity of headache was assessed with a standard questionnaire, and the serum levels of Selenium (Se), MDA, and TAC were measured via biochemical methods. The odds of migraine were calculated across quartile of Se and oxidative stress biomarkers via binary logistic regression. Migraine patients had a significant lower Se levels (81.06 ± 8.66 vs. 88.94 ± 10.23 μg/L, P = 0.002) and a significant higher MDA levels (3.04 ± 1.74 vs. 2.06 ± 0.59 nmol/ml, P = 0.005) compared to healthy participants. Although serum TAC levels (1.34 ± 0.34 vs.1.37 ± 0.33 mmol/L, P = 0.755) were not significantly different between migraine patients rather than healthy subjects. Individuals in the lowest quartile of Se levels were about eleven times more likely to have migraine than those in the highest quartile (OR: 11.2; 95%CI: 1.57 to 80.2; P-trend: 0.016). Besides, being in the highest quartile of the serum MDA level, the odds of having migraine increases 15.4 times compared to the lowest quartile (OR = 15.4, 95%CI: 1.1 to 221, P = 0.044). No significant association was found between TAC and migraine. The lower Se and MDA levels in migraine patients gives rise to the probability which oxidant status may play an underlying role in migraine pathophysiology.

The Impact of Mineral Supplementation on Polycystic Ovarian Syndrome

Polycystic ovary syndrome (PCOS) is an endocrinopathy that is common among women of reproductive age. It is a heterogeneous disorder with an unknown etiology. Different strategies have been proposed for the treatment of PCOS. Recent studies recommend supplementation with specific minerals for treating various PCOS phenotypes. We searched PubMed, Google Scholar, and SCOPUS databases by using search terms combining PCOS with the supplementation of magnesium, zinc, selenium, or chromium. This review presents a narrative concerning the association between PCOS and magnesium, zinc, selenium, and chromium supplementation. We review findings from various randomized controlled trials and meta-analyses conducted in women of childbearing age with PCOS. Recent reports highlight the beneficial effect of minerals on the clinical and metabolic symptoms of PCOS. Further studies are required to establish the appropriate dosage level of these minerals for ameliorating the pathologies associated with PCOS because of the potential health risks linked with higher doses.

Mechanistic Impact of Zinc Deficiency in Human Development

Zinc (Zn) deficiency in humans is an emerging global health issue affecting approximately two billion people across the globe. The situation prevails due to the intake of Zn deficient grains and vegetables worldwide. Clinical identification of Zn deficiency in humans remains problematic because the symptoms do not appear until impair the vital organs, such as the gastrointestinal track, central nervous system, immune system, skeletal, and nervous system. Lower Zn body levels are also responsible for multiple physiological disorders, such as apoptosis, organs destruction, DNA injuries, and oxidative damage to the cellular components through reactive oxygen species (ROS). The oxidative damage causes chronic inflammation lead toward several chronic diseases, such as heart diseases, cancers, alcohol-related malady, muscular contraction, and neuro-pathogenesis. The present review focused on the physiological and growth-related changes in humans under Zn deficient conditions, mechanisms adopted by the human body under Zn deficiency for the proper functioning of the body systems, and the importance of nutritional and nutraceutical approaches to overcome Zn deficiency in humans and concluded that the biofortified food is the best source of Zn as compared to the chemical supplementation to avoid their negative impacts on human.