Leptin and zinc relation: In regulation of food intake and immunity

Elemental comparative analysis of 18 elements reveal distinct patterns in benign and malignant thyroid tissues

This study aims to compare variations in 18 trace elements (Al, Na, K, Mg, Ca, Ti, Ba, Sn, Cr, Mn, Fe, Cu, Zn, Se, Mo, Cd, Sr, and Tl) between benign and malignant thyroid tissues. Post-operative thyroid tissue samples were collected from 106 patients (34 benign, 72 malignant), and elemental concentrations were quantified using inductively coupled plasma mass spectrometry. Spearman's correlation analysis revealed positive correlations among these trace elements. Notably, the malignant group exhibited significantly higher concentrations in eight elements (Mg, Al, Fe, Cr, Ti, Sr, Sn, and Ba) compared to the benign group, while levels of six elements (Na, Mn, Cu, Zn, Cd, and Mo) were significantly lower. Orthogonal partial least squares discriminant analysis distinguished three elements (Al, Ti, Sn) for the malignant group and six elements (Na, Mn, Cu, Zn, Cd, and Mo) for the benign group. Multivariate logistic regression further revealed associations between thyroid cancer and levels of Al, Cr, Ti, Sr, Sn, Ba, Mn, Cu, Zn, and Cd. Considering with each elemental biological funcions, these findings suggest that Cu, Mn, and particularly Zn may act as essential antitumor elements with synergistic effects, whereas elevated Ba, Cr, and Al levels are closely related to thyroid malignancies. However deficiencies and excesses of elements may be the consequences of malignant tissues. In conclusion, benign and malignant thyroid tumors exhibit different trace-element profiles.

Dietary zinc status is associated with ZnT3 (SLC30A3), IL-6 gene expressions and spinal cord tissue damage in spinal cord tissue in a cuprizone-induced rat Multiple Sclerosis model

The aim of this study was to investigate the effects of dietary zinc status on spinal cord tissue damage and ZnT3, IL-6 gene expressions in a cuprizone-induced rat Multiple Sclerosis (MS) model. The study was carried out on 46 adult male rats of the genus Wistar. The animals used in the study were divided into 5 groups (G) (Control 6, other groups 10). G1, Control. G2, Sham-MS: Carboxy-methyl-cellulose (KMS) solution in which Cuprizon was dissolved was given to rats by gavage daily for 8 weeks at the rate of 1 % of daily feed consumption. MS was formed by giving 1 % of the daily feed consumption cuprizon in KMS solution by gavage to the animals in G3, 4 and 5 for 8 weeks. G4 was fed with a zinc deficient (50 µg/kg zinc) diet. G5 was given intraperitoneal (ip) zinc sulfate (5 mg/kg/day) supplementation. MS formation in animals was determined by Rotarod tests and Myelin Basic Protein (MBP) gene expression analysis. ZNT3 and IL-6 gene expression levels in spinal cord tissue samples of animals by Real-Time-PCR method; MDA and GSH levels were determined by ELISA method. The highest spinal cord MDA and IL-6 levels were obtained in G3 and G4 (P<0.05). Zinc supplementation in G5 prevented the increase in the mentioned parameters and turned them into control values (P<0.05). The spinal cord GSH and ZnT3 levels of G3 and G4 were lower than all other groups (P<0.05). Zinc supplementation prevented suppression in the same parameters in G5 and reached the control values (P<0.05). The findings of the current study suggest that zinc supplementation in addition to treatment for MS may be beneficial in reducing the severity of the disease.

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.

Effect of Zinc Supplementation on Lipid Profile and Body Composition in Patients with Type 2 Diabetes Mellitus: A GRADE-Assessed Systematic Review and Dose-Response Meta-analysis

The aim of this systematic review and meta-analysis of randomized controlled trials (RCTs) is to investigate the overall effects of zinc supplementation on lipid profile and body composition such as body weight (BW), body mass index (BMI), triglycerides (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) in patients with type 2 diabetes mellitus (T2DM). Scopus, Web of Science, PubMed, and Embase databases were searched from inception through October, 2023. The I2 and Cochran's Q tests were used to assess heterogeneity between studies. Nineteen RCTs (n = 1357 participants) were included in the meta-analysis. Zinc supplementation significantly reduced TG (WMD = - 17.41 mg/dL; 95% CI: - 22.60, - 12.22; P < 0.001), TC (WMD: - 19.60 mg/dL; 95% CI: - 28.46, - 10.73, P < 0.001), LDL-C (WMD = - 8.80 mg/dL; 95% CI: - 14.80, - 2.81; P = 0.004), and BMI (WMD = - 0.53 kg/m2; 95% CI: - 1.05, - 0.01; P = 0.046) but not BW (WMD: - 0.51 kg, 95 % CI: - 1.99, 0.97, P = 0.498). Moreover, zinc supplementation increased HDL-C (WMD = 4.82 mg/dL; 95% CI: 0.88, 8.76; P = 0.016) in patients with T2DM. Our results propose that zinc supplementation may be an effective strategy for improving lipid profile and body composition in patients with T2DM.

Neuronutrition and Its Impact on Post-Stroke Neurorehabilitation: Modulating Plasticity Through Diet

The recovery of neurological deficits after ischemic stroke largely depends on the brain's ability to reorganize its undamaged neuronal circuits and neuronal plasticity phenomena. The consolidated evidence highlights the involvement of the patient's impaired nutritional conditions in post-stroke recovery and unsatisfying rehabilitative outcomes. Standardized nutritional protocols usually applied in hospitalized patients in a rehabilitation setting aim mainly to improve the general health conditions of patients, do not consider the high inter-individual variability in neurorehabilitation outcomes, and are not sufficiently modifiable to provide neuroprotective and restorative dietary patterns that could promote neuronal plasticity and functional recovery during neurorehabilitation. Neuronutrition, an emergent scientific field of neuroscience, represents a valid model of a personalized nutritional approach, assuring, for each patient, nutrients having antioxidant and anti-inflammatory properties, ensuring a balanced microbiota composition, and providing adequate neurotrophic support, essential for improving neuronal plasticity, brain functional recovery, and rehabilitative outcomes. In the present narrative review, we provide an overview of the current knowledge on neuronutrition as an adjuvant strategy of a personalized nutritional approach potentially effective in improving post-stroke neuroplasticity and neurorehabilitation by counteracting or at least limiting post-stroke oxidative/nitrosative stress, neuroinflammation, and gut-brain axis disturbance.

Zinc and Ferritin Levels and Their Associations with Functional Disorders and/or Thyroid Autoimmunity: A Population-Based Case-Control Study

Population zinc and iron status appear to be associated with an increased risk of thyroid function abnormalities and thyroid autoimmunity (AITD). In the present study, we aimed to determine whether zinc and/or iron levels (assessed by ferritin levels) were associated with the presence of AITD and with alterations in thyroid function. A population-based case-control study (n = 1048) was conducted (cases: n = 524; controls: n = 524). Participants were measured for blood concentrations of zinc and ferritin, TSH, FT4, FT3, and thyroid autoantibodies. No significant differences were found in relation to ferritin levels between cases and controls. Among cases, the prevalence of low zinc levels in those with hypothyroidism (both subclinical and overt) was 49.1% [odds ratio (OR) of low zinc levels: 5.926; 95% CI: 3.756-9.351]. The prevalence of low zinc levels in participants with hyperthyroidism (both subclinical and overt) was 37.5% [OR of low zinc levels: 3.683; 95% CI: 1.628-8.33]. The zinc value that best discriminated the highest frequency of AITD was 70.4 µg/dL [sensitivity: 0.947, 1-specificity: 0.655, specificity: 0.345]. The highest frequency of AITD was calculated based on a zinc value <70 µg/dL (relative to a normal value), with this frequency being significantly higher in cases than in controls [OR: 9.3; 95% CI: 6.1-14.3 (p = 0.001)]. In conclusion, the results of our study suggest that zinc deficiency is associated with an increased frequency of functional thyroid disorders and thyroid autoimmunity.

The role of zinc on nutritional status, sarcopenia, and frailty in older adults: a scoping review

BACKGROUND

Zinc (Zn) deficiency, malnutrition, sarcopenia, and frailty are prevalent among older adults and are prominent factors contributing to disability and mortality.

OBJECTIVE

This scoping review was conducted to aid understanding of the extent and types of research addressing the role of Zn in nutritional status, sarcopenia, and frailty, among older individuals.

METHOD

A systematic search was performed in August 2022 of 3 electronic databases (PubMed, Web of Science, and ProQuest) using predefined search terms. The review was conducted referring to the Arksey and O'Malley framework and PRISMA-ScR.

RESULTS

The search retrieved 16 018 records, and a total of 49 studies were included in this review after the screening. Of those, 30 were based on dietary Zn intake, 18 on tissue Zn levels, and 1 on both. Most studies were based on cross-sectional data from community-dwelling older adults. Studies addressing the associations between Zn status and individual anthropometric and sarcopenia-related variables reported inconsistent results. However, most studies reported inverse associations between malnutrition, frailty, and Zn status.

CONCLUSION

There was more consistent evidence of the relationship of Zn status with malnutrition, sarcopenia, and frailty rather than with individual nutritional parameters. Validated screening and assessment tools and criteria and prospective studies are required to elucidate the relationship of Zn with sarcopenia and frailty in the older population.

Intergenerational Impact of Parental Zinc Deficiency on Metabolic and Redox Outcomes in Drosophila melanogaster

Zinc deficiency is a common nutritional disorder with detrimental health consequences. Whether parental zinc deficiency induces intergenerational effects remains largely unknown. We investigated the effects of a combined maternal and paternal zinc deficiency on offspring's metabolic outcomes and gene expression changes in Drosophila melanogaster. The parent flies were raised on zinc-deficient diets throughout development, and their progeny were assessed. Offspring from zinc-deprived parents exhibited a significant (p < 0.05) increase in body weight and whole-body zinc levels. They also displayed disrupted glucose metabolism, altered lipid homeostasis, and diminished activity of antioxidant enzymes. Gene expression analysis revealed significant (p < 0.05) alterations in zinc transport genes, with increases in mRNA levels of dZIP1 and dZnT1 for female and male offspring, respectively. Both sexes exhibited reduced dZnT35C mRNA levels and significant (p < 0.05) increases in the mRNA levels of DILP2 and proinflammatory markers, Eiger and UPD2. Overall, female offspring showed higher sensitivity to parental zinc deficiency. Our findings underscore zinc's crucial role in maintaining health and the gender-specific responses to zinc deficiency. There is the need for further exploration of the underlying mechanisms behind these intergenerational effects.

Impact of resveratrol and zinc on biomarkers of oxidative stress induced by Trichinella spiralis infection

Trichinellosis is a re-emerging worldwide foodborne zoonosis. Oxidative stress is one of the most common detrimental effects caused by trichinellosis. In addition, Trichinella infection poses an infinite and major challenge to the host's immune system. Resistance and side effects limit the efficiency of the existing anti-trichinella medication. Given that concern, this work aimed to investigate the anti-helminthic, antioxidant, anti-inflammatory and immunomodulatory effects of resveratrol and zinc during both phases of Trichinella spiralis infection. Sixty-four Swiss albino mice were divided into four equal groups: non-infected control, infected control, infected and treated with resveratrol, and infected and treated with zinc. Animals were sacrificed on the 7th and 35th days post-infection for intestinal and muscular phase assessments. Drug efficacy was assessed by biochemical, parasitological, histopathological, immunological, and immunohistochemical assays. Resveratrol and zinc can be promising antiparasitic, antioxidant, anti-inflammatory, and immunomodulatory agents, as evidenced by the significant decrease in parasite burden, the significant improvement of liver and kidney function parameters, the increase in total antioxidant capacity (TAC), the reduction of malondialdehyde (MDA) level, the increase in nuclear factor (erythroid-derived 2)-like-2 factor expression, and the improvement in histopathological findings. Moreover, both drugs enhanced the immune system and restored the disturbed immune balance by increasing the interleukin 12 (IL-12) level. In conclusion, resveratrol and zinc provide protection for the host against oxidative harm and the detrimental effects produced by the host's defense response during Trichinella spiralis infection, making them promising natural alternatives for the treatment of trichinellosis.

Therapeutic effect of trace elements on multiple myeloma and mechanisms of cancer process

In the human body, trace elements and other micronutrients play a vital role in growth, health and immune system function. The trace elements are Iron, Manganese, Copper, Iodine, Zinc, Cobalt, Fluoride, and Selenium. Estimating the serum levels of trace elements in hematologic malignancy patients can determine the severity of the tumor. Multiple myeloma (MM) is a hematopoietic malignancy and is characterized by plasma cell clonal expansion in bone marrow. Despite the advances in treatment methods, myeloma remains largely incurable. In addition to conventional medicine, treatment is moving toward less expensive noninvasive alternatives. One of the alternative treatments is the use of dietary supplements. In this review, we focused on the effect of three trace elements including iron, zinc and selenium on important mechanisms such as the immune system, oxidative and antioxidant factors and cell cycle. Using some trace minerals in combination with approved drugs can increase patients' recovery speed. Trace elements can be used as not only a preventive but also a therapeutic tool, especially in reducing inflammation in hematological cancers such as multiple myeloma. We hope that the prospect of the correct use of trace element supplements in the future could be promising for the treatment of diseases.

The causal effect of serum micronutrients on malignant kidney neoplasm in European descent

Purpose

Observational studies have revealed that serum minerals and vitamins are associated with cancer. However, the causal relationships between serum minerals and vitamins and renal malignancies remain unclear.

Methods

Mendelian randomization (MR) was used for causal estimation. Single nucleotide polymorphisms (SNPs) for serum minerals and vitamins were obtained from published genome-wide association studies (GWAS). GWAS for malignant kidney neoplasm was obtained from the FinnGen consortium. Methods of inverse variance weighted (IVW), MR-Egger, and weighted median were carried out for causal inference. F-statistic was calculated to ensure a robust instrumental variable. Cochran's Q statistics was applied to calculate heterogeneity. MR-Egger regression, MR-pleiotropy residual sum and outlier methods (MR-PRESSO) methods were used to perform pleiotropy analysis. Meanwhile, confounding factors were considered to determine whether causal inference would be biased.

Results

Eight different micronutrients were included (zinc, iron, magnesium, calcium, copper, selenium, phosphate, and vitamin B12). After MR analysis, we found a protective effect of serum zinc against malignant kidney neoplasm (IVW: odds ratios (ORs), 0.86; 95% confidence interval (95% CI), 0.78-0.94; p, 0.0016; MR-Egger: OR, 0.80; 95% CI, 0.64-0.97; p, 0.052; weighted median: OR, 0.85; 95% CI, 0.75-0.96; p, 0.011). Causal relationships between other micronutrients and malignant kidney neoplasm were not obtained. No heterogeneity and pleiotropy were detected, while causality was not biased by confounding factors.

Conclusion

We considered that serum zinc exerted a protective effect against malignant kidney neoplasm. In clinical practice, for people with high malignant kidney neoplasm risk, an oral zinc supplementation might play a role in a potential therapeutic target.

Childhood Obesity and Essential Micronutrients: Insights from India's Comprehensive National Nutrition Survey (2016-18)

INTRODUCTION

Based on the long-term impact of childhood obesity, there is a compelling need to assess the burden of obesity and micronutrient deficiency and the interactions between the two. Thus, the aims of the study were to estimate the prevalence of overweight and obese children and adolescents to compare micro-nutrient levels in these children with normal and underweight categories and explore the factors affecting overweight and obesity in the presence of micronutrient deficiencies.

METHODS

Secondary data analysis of the Comprehensive National Nutrition Survey-India (2017-2018) was done. The survey recorded information from 112,245 preschool children (6-60 months), school age children (5-9 years), and adolescents (10-19 years). Half of these participants were invited for biochemical testing and were included in our analysis. The presence of overweight or obesity and micronutrient (serum erythrocyte folate; vitamin B12, A, and D; ferritin; zinc; and urinary iodine) deficiencies were the primary outcomes. The secondary outcome included the mean serum levels and predictors of overweight and obesity in the presence of micronutrient deficiencies.

RESULTS

Of the 38,060, 38,355, and 35,830 preschool, school-age, and adolescent study participants, about 2.69, 4.18, and 4.99% were overweight or obese. We observed significant variations in the mean folate and vitamin B12 levels among the overweight and obese preschool and school-age children compared to the normal weight group. School-age children exhibited significant differences in all micronutrient levels. In contrast, adolescents only showed substantial differences in vitamin D and A and serum ferritin levels. The predictors of overweight and obesity included geographical locations, wealth quintiles, and societal castes. Iron, folate, vitamin D, and zinc levels significantly affect the odds of developing childhood overweight and obesity.

CONCLUSIONS

It is vital to halt the growing burden of childhood overweight and obesity. Addressing micronutrient deficiencies can help us bring a sustainable and feasible approach to managing this menace.

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.

Novel ketamine and zinc treatment for anorexia nervosa and the potential beneficial interactions with the gut microbiome

Anorexia nervosa (AN) is a severe illness with diverse aetiological and maintaining contributors including neurobiological, metabolic, psychological, and social determining factors. In addition to nutritional recovery, multiple psychological and pharmacological therapies and brain-based stimulations have been explored; however, existing treatments have limited efficacy. This paper outlines a neurobiological model of glutamatergic and γ-aminobutyric acid (GABA)-ergic dysfunction, exacerbated by chronic gut microbiome dysbiosis and zinc depletion at a brain and gut level. The gut microbiome is established early in development, and early exposure to stress and adversity contribute to gut microbial disturbance in AN, early dysregulation to glutamatergic and GABAergic networks, interoceptive impairment, and inhibited caloric harvest from food (e.g., zinc malabsorption, competition for zinc ions between gut bacteria and host). Zinc is a key part of glutamatergic and GABAergic networks, and also affects leptin and gut microbial function; systems dysregulated in AN. Low doses of ketamine in conjunction with zinc, could provide an efficacious combination to act on NMDA receptors and normalise glutamatergic, GABAergic and gut function in AN.

Influence of Oxidative Stress and Inflammation on Nutritional Status and Neural Plasticity: New Perspectives on Post-Stroke Neurorehabilitative Outcome

Beyond brain deficits caused by strokes, the effectiveness of neurorehabilitation is strongly influenced by the baseline clinical features of stroke patients, including a patient's current nutritional status. Malnutrition, either as a pre-stroke existing condition or occurring because of ischemic injury, predisposes patients to poor rehabilitation outcomes. On the other hand, a proper nutritional status compliant with the specific needs required by the process of brain recovery plays a key role in post-stroke rehabilitative outcome favoring neuroplasticity mechanisms. Oxidative stress and inflammation play a role in stroke-associated malnutrition, as well as in the cascade of ischemic events in the brain area, where ischemic damage leads to neuronal death and brain infarction, and, via cell-to-cell signaling, the alteration of neuroplasticity processes underlying functional recovery induced by multidisciplinary rehabilitative treatment. Nutrition strategies based on food components with oxidative and anti-inflammatory properties may help to reverse or stop malnutrition and may be a prerequisite for supporting the ability of neuronal plasticity to result in satisfactory rehabilitative outcome in stroke patients. To expand nutritional recommendations for functional rehabilitation recovery, studies considering the evolution of nutritional status changes in post-stroke patients over time are required. The assessment of nutritional status must be included as a routine tool in rehabilitation settings for the integrated care of stroke-patients.

Depletion of Zinc Causes Osteoblast Apoptosis with Elevation of Leptin Secretion and Phosphorylation of JAK2/STAT3

Zinc (Zn) has been reported to mediate leptin secretion, and thus leptin can be an important candidate molecule linking Zn with bone formation. The present study investigated whether zinc deficiency induces leptin secretion by activating a JAK2/STAT3 signaling pathway and leads to osteoblastic apoptosis. MC3T3-E1 cells were incubated for 24 h in normal osteogenic differentiation medium (OSM) or OSM treated with either 1 μM (Low Zn) or 15 μM (High Zn) of ZnCl₂ containing 5 μM TPEN (Zn chelator). Our results demonstrated that low Zn stimulated extracellular leptin secretion and increased mRNA and protein expression of leptin in osteoblastic MC3T3-E1 cells. The OB-Rb (long isoform of leptin receptor) expressions were also elevated in osteoblasts under depletion of Zn. Leptin-signaling proteins, JAK2 and p-JAK2 in the cytosol of low Zn osteoblast conveyed leptin signaling, which ultimately induced higher p-STAT3 expression in the nucleus. Apoptotic effects of JAK2/STAT3 pathway were shown by increased caspase-3 in low Zn osteoblasts as well as apoptotic morphological features observed by TEM. Together, these data suggest that low Zn modulates leptin secretion by activating JAK2/STAT3 signaling pathway and induces apoptosis of osteoblastic MC3T3-E1 cells.

The Association between Index of Nutritional Quality (INQ) and Obesity: Baseline Data of Kharameh Cohort

Obesity is an increasing problem that can lead to noncommunicable diseases. The role of dietary factors on one's obesity is confirmed in many studies. One nutritional approach that can be used for assessment of the foods and diets is the Index of Nutritional Quality (INQ). Our study is aimed at exploring the association between INQ and obesity. Our hypothesis is that enriched and high-quality diets reduce the risk of overweight or obesity. This study was carried out on 6248 overweight and obese participants, from whom 4356 (69.7%) and 1892 (30.3%) were overweight and obese, respectively. To assess the dietary intake for the participants, a valid food frequency questionnaire (FFQ) with 130 food items was utilized. The analysis revealed an inverse association between the overweight and the INQ of iron, thiamin, riboflavin, B6, folate, zinc, magnesium, calcium, and vitamin C and E. For the obese group, this inverse association was found for iron, B6, folate, zinc, magnesium, calcium, and vitamin C and E. These results approved our hypothesis that a rich nutrition diet may lead to a lower risk of obesity.

Beneficial effects of Se/Zn co-supplementation on body weight and adipose tissue inflammation in high-fat diet-induced obese rats

This research investigated the effect of co-supplementation of selenium with zinc on weight control and the inflammatory and oxidative status in relation to obesity. Male Wistar rats (N = 32) were randomly divided into four groups after induction of obesity model: 1) "Zn" was supplemented with zinc sulfate (15 mg/kg BW), 2) "Se" supplemented with selenium as sodium selenate (0.5 mg/kg BW), 3) "Zn + Se" which received Zn (15 mg/kg BW) + Se (0.5 mg/kg BW), and 4) "HFD" as the control group. The intervention was done for eight weeks. At the end of treatment, serum and tissue level of Zn, Se, SOD, GSH-Px, MDA, leptin, TNF-α, and IL-6 was evaluated. Weight and food intake were significantly reduced in the Se group(p < .001), while in the Zn group, weight gain due to obesity was prevented compared to the control group (p = .48). There was a significant and stronger increase in SOD, GSH-Px levels and a remarkable decrease in MDA, leptin, TNF-α, and IL-6 in the group receiving the combination of two supplements than either alone(p < .001). Leptin had a positive correlation with inflammatory factors and lipid peroxidation marker and showed an inverse relationship with Zn and Se levels and anti-oxidative enzymes(p < .05). The analysis showed the mediating role of leptin in the effects of zinc. Co-supplementation of selenium and zinc may have a synergistic effect in reduction of oxidative and inflammatory markers. Regarding the effect of zinc on inflammatory factors and lipid peroxidation, leptin can play a mediating role.

Effect of zinc supplementation on mortality in under 5-year children: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Several clinical trials evaluated the effect of zinc supplementation on mortality in children, but the results were inconsistent. We aimed to conduct a systematic review and meta-analysis on the impact of zinc supplementation on mortality in under 5-year children.

METHODS

A comprehensive search was conducted using the electronic (PubMed, Scopus, Web of Science) databases, and Google Scholar, up to June 2020. Randomized clinical trials (RCTs) that reported the effect of zinc supplementation on death incidence in under 5-year children were included in the analysis. Screening was performed based on title/abstract and full-text. A random effects model was applied to calculate the summary relative risk (SRR). Risk of Bias 2.0 tool was used to rate the quality of trials. The body of evidence was assessed by the GRADE approach.

RESULTS

Combining 30 RRs from 28 RCTs including 237,068 participants revealed that zinc supplementation has significantly reduced the risk of all-causes mortality by 16% in children (SRR: 0.84, 95% CI: 0.74, 0.96). A follow-up duration of less than 1 year after supplementation resulted in 54% reduced risk of mortality (0.46; 0.33, 0.63) with no heterogeneity between investigations. Subgroup analysis by zinc dosage showed that assigning ≥ 10 mg/d zinc to under five children and duration of less than 11 months of intervention decreased the risk of all-cause mortality by 44% (0.56; 0.42, 0.75) and 48% (0.52; 0.38, 0.72), respectively. In low birth weight (LBW) infants, zinc supplementation was reduced all-cause mortality by 52% (0.48; 0.23, 1.00). Zinc supplementation significantly reduced the risk of death from pneumonia (0.70: 0.64, 0.98) and infection (0.54; 0.39, 0.76), also changed the risk of mortality from diarrhea by 15% (0.85; 0.70, 1.03) and sepsis by 57% (0.43; 0.18, 1.02).

CONCLUSION

This meta-analysis on RCTs revealed that zinc supplementation in under 5-year children has significantly reduced the risk of all-cause mortality. Notable decreases were found in trials with a dose of 10 mg/d or more zinc supplementation, a maximum of 11 months of supplementation, a follow-up less than one year and especially in LBW infants.

Index of Nutritional Quality (INQ) and the Risk of Obesity in Male Adolescents: a Case-Control Study

Dietary factors may play a key role in the etiology of obesity. The Index of Nutritional Quality (INQ) provides a comprehensive overview of the nutrients content of the diet. This study aimed to investigate the association between INQ and obesity in male adolescents. We hypothesize that receiving a high-quality diet reduces the risk of overweight or obese. This study was carried out on 214 obese/overweight as the case group and 321 normal-weight male adolescents as the control group. Dietary intakes of the participants were collected using a food frequency questionnaire (FFQ). The FFQ-derived dietary data were used to calculate the INQ scores. After adjustments for age and height, an inverse association was found between obesity and INQ of iron, vitamin B6, and magnesium, and a positive association was found between obesity and INQ of zinc (all P < 0.05). After further adjustments for nutritional knowledge and calorie intake, an inverse association was observed between obesity and INQ of vitamin C, iron, vitamin B6, pantothenic acid, selenium, and magnesium (all P < 0.05). The positive association of obesity and INQ of zinc remained significant after adjustments. A higher intake of vitamin C, iron, vitamin B6, pantothenic acid, selenium, and magnesium and a lower intake of zinc may be protective against adolescent obesity. More longitudinal studies are required to investigate the relationship between these nutrients and obesity.

Zinc Supplementation Might Not Affect Serum Leptin and Adiponectin Levels in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials

Background:

Zinc as one of the important trace elements in human health has been suggested to be a supplement for modifying the level of adipokines, whereas findings from studies have been inconsistent. This study aimed to systematically review the evidence provided by randomized controlled trials (RCTs) regarding the effect of zinc supplementation on serum adipokines levels.

Methods:

PubMed, Google Scholar, Web of Science, and Scopus were systematically searched up to June 2019. The mean differences and their corresponding standard deviations (SDs) of changes in serum adipokines levels were used as effect size.

Results:

Eight eligible RCTs (leptin n=6, adiponectin n=3) were included in the current study. There were no significant changes in serum leptin levels [weighted mean difference (WMD) =0.60 ng/ml, 95% confidence interval (CI): −1.78, 2.99; I-squared (I²) = 64.3%] and adiponectin levels (WMD = 1.09 ng/ml, 95% CI: −0.76, 3.18, I² = 78.8%) following zinc supplementation compared to placebo group. These findings did not change after considering several subgroups including gender, study duration, health status, body weight and the type of zinc used for supplementation.

Conclusion:

No evidence was found to support the efficacy of dietary zinc supplements on serum levels of adipokines. Further, high-quality, long-term controlled clinical trials are warranted to confirm these findings.

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

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

Association of Serum Zinc Levels in Overweight and Obesity

Low levels of zinc (Zn) have adverse effects on physiological and metabolic functions in humans, especially in processes linked with obesity. In this work, serum Zn levels and their associations with biochemical parameters (glucose, triglycerides, and total cholesterol), sex, and body mass index (BMI) were determined. The distribution of the study sample by sex was homogeneous: 52.6% were women and 47.4% were men. Women had higher BMI and Zn levels (normal weight and obesity) than men, but the differences in BMI and serum Zn levels by sex were not significant (p > 0.05). Nevertheless, the results obtained showed a decrease in serum Zn levels in overweight and obese individuals (p < 0.05) and a negative correlation between BMI and serum Zn levels (r = - 0.663 and p < 0.001); additionally, a significant correlation was identified between cholesterol and triglyceride values (r = 0.493 and p < 0.001). In conclusion, this study demonstrated decreased serum Zn levels in overweight and obese individuals.

A Search for Similar Patterns in Hair Trace Element and Mineral Content in Children with Down's Syndrome, Obesity, and Growth Delay

The objective of the present study was to perform comparative analysis of hair trace element and mineral levels in children with Down's syndrome, growth delay, and obesity in order to reveal common and specific patterns. Hair Zn (14, 7, and 15%), Ca (38%, 24%, and 47%), and Mg (33%, 31%, and 49%) levels in children with Down's syndrome, obesity, and growth delay were lower than the respective control values. At the same time, patients with Down's syndrome and growth delay were characterized by 27% and 21%, as well as 24% and 20% lower hair Co as well as Cu content than healthy examinees. Certain alterations were found to be disease-specific. Particularly, in Down's syndrome children, hair Cr, Fe, and V levels were significantly lower, whereas hair P content exceeded the control values. Obese children were characterized by significantly increased hair Cr content. At the same time, hair Mn and Si levels in children with growth delay were lower as compared with the controls. In regression models, all three studied diseases were considered as negative predictors of hair Cu content. Down's syndrome and growth delay, but not obesity, were inversely associated with hair Co content. Both Down's syndrome and obesity were inversely associated with hair Zn content. Based on the revealed similarities in altered hair element, content it is proposed that deficiency of essential elements may predispose Down's syndrome patients to certain syndrome comorbidities including growth delay and obesity, although further detailed studies are required.

Zinc Supplementation and Body Weight: A Systematic Review and Dose-Response Meta-analysis of Randomized Controlled Trials

The aim of this study was to determine the effect of zinc supplementation on anthropometric measures. In this systematic review and dose-response meta-analysis, we searched PubMed, Scopus, ISI Web of Science, and the Cochrane Library from database inception to August 2018 for relevant randomized controlled trials. Mean differences and SDs for each outcome were pooled using a random-effects model. Furthermore, a dose-response analysis for zinc dosage was performed using a fractional polynomial model. Quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Twenty-seven trials (n = 1438 participants) were included in the meta-analysis. There were no significant changes in anthropometric measures after zinc supplementation in the overall analysis. However, subgroup analyses revealed that zinc supplementation increased body weight in individuals undergoing hemodialysis (HD) [3 trials, n = 154 participants; weighted mean difference (WMD) = 1.02 kg; 95% CI: 0.38, 1.65 kg; P = 0.002; I2 = 11.4%] and decreased body weight in subjects who are overweight/obese but otherwise healthy (5 trials, n = 245 participants; WMD = -0.55 kg; 95% CI: -1.06, -0.04 kg; P = 0.03; I2 = 31.5%). Dose-response analyses revealed a significant nonlinear effect of supplementation dosage on BMI (P = 0.001). Our data suggest that zinc supplementation increases body weight in patients undergoing HD and decreases body weight in individuals who are overweight/obese but otherwise healthy, although after normalization for study duration, the association observed in subjects who are overweight/obese disappeared. Although more high-quality studies are needed to reach a definitive conclusion, our study supports the view that zinc may be associated with body weight.

Specialized hypocholesterolemic foods: Ingredients, technology, effects

Introduction. Overweight and obesity are leading risk factors for metabolic syndrome (MS). From 20 to 35% of Russian people have this condition, depending on their age. MS is a precursor of cardiovascular disease, diabetes mellitus, diabetic nephropathy, and nonalcoholic steatohepatitis. Specialized foods (SFs) with hypocholesteremic effects are an important component of the diet therapy for MS patients. Creating local SFs to optimize the nutritional status of MS patients and prevent related diseases is a highly promising area of research. The aim of our study was to develop the formulation and technology of SFs and evaluate their effectiveness in MS treatment. Study objects and methods. The objects of the study were food ingredients and SFs. Safety indicators and micronutrient contents were determined by standard methods, whereas nutritional and energy values and amino acid contents were determined by calculation. Results and discussion. Based on medical requirements, we selected functional ingredients and developed a formulation and technology of SFs with an optimized protein, fat, and carbohydrate composition. The formulation included essential micronutrients and biologically active substances with a desirable physiological effect. Clinical trials involved 15 MS patients aged from 27 to 59. For two weeks, they had a low-calorie standard diet with one serving of SFs in the form of a drink instead of a second breakfast. The patients showed a significant improvement in anthropometric indicators. Blood serum tests revealed decreased contents of total cholesterol (by 16.9%), low-density lipoprotein cholesterol (by 15.3%), and triglycerides (by 27.9%). Conclusion. We developed technical specifications and produced a pilot batch of SFs. The trials showed an improvement of lipid metabolism in the MS patients who were taking SFs as part of their diet therapy.

Lowered zinc and copper levels in drug-naïve patients with major depression: Effects of antidepressants, ketoprofen and immune activation

Objectives: The aim of the present work is to examine the effects of treatment with sertraline with and without ketoprofen on serum levels of zinc and copper in association with immune-inflammatory biomarkers in drug-naïve major depressed patients.Methods: We measured serum zinc and copper, interleukin (IL)-1β, IL-4, IL-6, IL-18, interferon-γ, and transforming growth factor-β1 in 40 controls and 133 depressed patients. The clinical efficacy of the treatment was measured using the Beck Depression Inventory-II (BDI-II) at baseline and 8 weeks later.Results: We found significantly reduced serum zinc and copper in association with upregulation of all cytokines, indicating activation of the immune-inflammatory responses system (IRS) and the compensatory immune regulatory system (CIRS). Treatment with sertraline significantly increased zinc and decreased copper. During treatment, there was a significant inverse association between serum zinc and immune activation. The improvement in the BDI-II during treatment was significantly associated with increments in serum zinc coupled with attenuation of the IRS/CIRS.Conclusions: Lower zinc is a hallmark of depression, while increments in serum zinc and attenuation of the immune-inflammatory response during treatment appear to play a role in the clinical efficacy of sertraline.

Zinc supplementation improves body weight management, inflammatory biomarkers and insulin resistance in individuals with obesity: a randomized, placebo-controlled, double-blind trial

BACKGROUND

The present study was designed to determine whether zinc supplementation would increase the effects of restricted calorie diet (RCD) on obesity.

METHODS AND MATERIALS

A randomized, double-blind clinical trial was performed on 40 obese subjects who were randomly assigned to receive zinc supplements (30 mg/day) or placebo for a period of 15-weeks. Both groups were under a restricted calorie diet (~ 300 kcal lower than the estimated energy requirement). Anthropometric measurements, biochemical markers, appetite, and dietary intakes were determined during the study period.

RESULTS

The reductions of body weight, body mass index, waist circumference, and hip circumference were significantly higher in the zinc group compared to the placebo group (P = 0.032, 0.025, 0.003, and 0.0001, respectively). Lower levels of high sensitivity C-reactive protein, apelin, homeostatic model assessment of insulin resistance (HOMA-IR), and appetite score were observed in the zinc group in comparison with the placebo group (P = 0.0001, 0.001, 0.031 and 0.001 respectively).

CONCLUSION

This study indicates that Zn supplementation with a restricted calorie diet has favorable effects in reducing anthropometric measurements, inflammatory markers, insulin resistance and appetite in individuals with obesity, and may play an effective role in the treatment of obesity.Trial registration This clinical trial was registered at clinicaltrials.gov at the U.S. National Library of Medicine (NCT02516475).

Association between inflammation, oxidative stress, vitamin D, copper and zinc with pre-obesity and obesity in school children from the city of Podgorica, Montenegro

Background Childhood obesity is a serious health condition with increasing rates worldwide. The aim of this study was to investigate the association between inflammation, oxidative stress, vitamin D, copper and zinc in pre-obese and obese children compared to controls. Methods The study involved 202 children aged 7-15 years (63.9% boys), randomly chosen from 10 elementary schools in Podgorica, Montenegro. Participants were divided into three groups according to their nutritional status (International Obesity Task Force [IOTF] criteria): normal-weight (42.1%), pre-obese (40.6%) and obese (17.3%). Serum biochemical analyses were performed (C-reactive protein [CRP], retinol-binding protein [RBP], total antioxidant status [TAS], total vitamin D [VD], copper and zinc). Results Serum TAS and CRP concentrations were higher in pre-obese and obese children compared to controls (p < 0.001). Serum VD concentrations were lower in pre-obese and obese children compared to their normal-weight peers (p = 0.027 and p = 0.054, respectively). Copper, zinc and RBP concentrations did not differ significantly among the groups (p > 0.05). In pre-obese and obese children, a positive correlation was found between CRP and copper (r = 0.305, p = 0.011 and r = 0.440, p = 0.013, respectively), and TAS and RBP (r = 0.528, p < 0.001 and r = 0.434, p = 0.015, respectively). Standard regression analyses showed that CRP and TAS increase (p < 0.001) whereas VD decreases (p = 0.011) with the body mass index (BMI). Conclusions We show that pre-obesity and obesity in childhood are positively associated with oxidative stress and inflammation, and inversely associated with VD status. Copper and zinc concentrations were not associated with excess fat in children.

Role of Zinc in Immune System and Anti-Cancer Defense Mechanisms

The human body cannot store zinc reserves, so a deficiency can arise relatively quickly, e.g., through an improper diet. Severe zinc deficiency is rare, but mild deficiencies are common around the world. Many epidemiological studies have shown a relationship between the zinc content in the diet and the risk of cancer. The anti-cancer effect of zinc is most often associated with its antioxidant properties. However, this is just one of many possibilities, including the influence of zinc on the immune system, transcription factors, cell differentiation and proliferation, DNA and RNA synthesis and repair, enzyme activation or inhibition, the regulation of cellular signaling, and the stabilization of the cell structure and membranes. This study presents selected issues regarding the current knowledge of anti-cancer mechanisms involving this element.

Morphological changes in spleen after dietary zinc deficiency and supplementation in Wistar rats

BACKGROUND

Study was conducted to determine the effect of dietary zinc deficiency and supplementation on the spleen morphology.

METHODS

Pre-pubertal Wistar rats (40-50 g) were divided into two groups with 6 sub-groups each viz. zinc control (ZC, 100 μg/g zinc diet), pair fed (PF, 100 μg/g zinc diet), zinc deficient (ZD, <1 μg/g zinc diet, zinc supplementation control (ZCS), zinc supplementation pair-fed (PFS) and zinc supplementation deficient (ZDS, 100 μg/g zinc control diet). Experiments were set for 2- and 4-weeks followed by 4 weeks of zinc supplementation.

RESULTS

In the present study body weight and BMI decreased significantly along with incidence of splenomegaly as typified by the increased splenic index in deficient groups compared with that of respective control groups. Histopathological changes such as disorganization of red pulp, several infiltered lymphocytes, vacuolization, loss of cellularity, karyolysis, dissolution of matrix, indistinct differentiation between red and white pulp were evident in spleen of 2ZD and 4ZD group animals. Degeneration was more severe after 4 weeks of zinc deficiency as giant cells formation and hypertrophy were also evident.

CONCLUSION

The findings revealed that zinc deficiency causes growth retardation and splenomegaly. Degenerative and atrophic changes in rat spleen suggest reduced cellular defense potential which will have a direct effect on immunity. Zinc supplementation may prove to be beneficial as there were varying degrees of cellular recovery after cessation of zinc deficiency.

Orexigenic action of oral zinc: metabolomic analysis in the rat hypothalamus

We previously reported an orexigenic action of oral zinc administration in male Sprague-Dawley (SD) rats during an early stage of feeding with a zinc-deficient diet, without decreased zinc concentrations in tissues. The overall conclusion was that orally but not intraperitoneally administered zinc stimulates food intake in short-term zinc-deficient-diet fed rats. We here investigate the mechanism of the orexigenic action of zinc using GC-MS/MS-targeted metabolomic analysis in the rat hypothalamus. Four-week-old, male SD/Slc rats were used, and after 2 days of feeding with a zinc-deficient diet, 3 mg of ZnSO₄ in 5 mL saline solution were administered to each rat either orally or intraperitoneally. Three hours after administration, the rats were sacrificed and the hypothalamus were excised and analyzed. We found that the oral administration group showed increased concentrations of 3-aminopropanoic acid (β-alanine), hypotaurine, dopamine, and biotin. In light of metabolomic analysis of these results, we indicate directions for further research.

The effect of zinc and melatonin supplementation on immunity parameters in breast cancer induced by DMBA in rats

OBJECTIVE

The aim of the study was to determine the effects of zinc and melatonin supplements on the immunity parameters of female rats with breast cancer induced by DMBA.

METHODS

Group 1; Control, Group 2; 7,12-dimethylbenz[a]anthracene (DMBA), Group 3; DMBA + zinc, Group 4; DMBA + melatonin, Group 5; DMBA + zinc + melatonin. The rats' breast cancer was induced by DMBA 80 mg/kg. Groups 3-5 received daily 5 mg/kg doses of zinc, melatonin, and zinc + melatonin, respectively. Lymphocyte rates, T-lymphocyte subgroups, B-lymphocyte and natural killer cells (NK), and natural killer T (NKT) were evaluated.

RESULTS

The most significant increase in lymphocyte, T-lymphocyte, and CD4 lymphocyte rates was found in Group 5. The highest NKT cell rates were found in Group 3.

CONCLUSIONS

Findings show that zinc and melatonin supplements have led to an increase in the immunity parameters of rats with breast cancer.

Zinc/alogliptin combination attenuates testicular toxicity induced by doxorubicin in rats: Role of oxidative stress, apoptosis and TGF-β1/NF-κB signaling

The aim of this study was to assess the effect of alogliptin and/or zinc on doxorubicin (DOX)-induced testicular toxicity in rats. Sixty male Wistar rats were divided into 6 equal groups: Control; DOX; DOX+Zinc; DOX+Alogliptin; DOX+Carboxymethyl cellulose and DOX+Zinc+Alogliptin. Testis weight, testicular functions, serum testosterone, luteinizing hormone, follicle stimulating hormone and zinc were measured. Also, testicular tissue zinc, 3 β-hydroxysteroid dehydrogenase, 17 β- hydroxysteroid dehydrogenase, antioxidant enzymes, pro-inflammatory cytokines, transforming growth factor beta 1 (TGF-β1), nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and sperm characteristics were assessed. Parts of the testes were subjected to histopathological and immunohistochemical examination. Zinc/alogliptin combination restored the testicular weight and functions, sperm characteristics, serum and tissue zinc levels, hormonal profile and the antioxidant defenses compared to the use of each of these drugs alone. Also, this combination induced significant amelioration of the inflammatory processes, significant increase in tissue Nrf2 content and significant improvement of the histopathological and immunohistochemical picture compared to the use of each of these drugs alone. So, zinc/alogliptin combination might represent a promising therapeutic modality for amelioration of DOX-induced testicular toxicity.

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

A number of studies have reported that zinc plays a substantial role in the development of metabolic syndrome, taking part in the regulation of cytokine expression, suppressing inflammation, and is also required to activate antioxidant enzymes that scavenge reactive oxygen species, reducing oxidative stress. Zinc also plays a role in the correct functioning of lipid and glucose metabolism, regulating and forming the expression of insulin. In numerous studies, zinc supplementation has been found to improve blood pressure, glucose, and LDL cholesterol serum level. Deeper knowledge of zinc's properties may help in treating metabolic syndrome, thus protecting against stroke and angina pectoris, and ultimately against death.

Association between serum zinc and later development of metabolic syndrome in middle aged and older men: The Kuopio Ischaemic Heart Disease Risk Factor Study

OBJECTIVE

The aim of this study was to investigate associations of serum zinc with incident metabolic syndrome and its components in middle-aged and older Finnish men.

METHODS

An 11-y prospective follow-up study conducted among 683 men from the Kuopio Ischaemic Heart Disease Risk Factor Study who were 42 to 60 y old at baseline in 1984 to 1989. The main outcome was incident metabolic syndrome, defined by the National Cholesterol Education Program (NCEP) criteria. Other outcomes were the individual components of the NCEP metabolic syndrome: Fasting blood glucose, serum triacylglycerols, serum high-density lipoprotein (HDL) cholesterol, hypertension, and waist circumference.

RESULTS

During the average follow-up of 11 y, 139 men (20.4%) developed metabolic syndrome. Those in the highest tertile of serum zinc had 84% higher risk (95% confidence interval 12 to 201%, P trend across tertiles = 0.015) to develop metabolic syndrome compared with those in the lowest tertile, after adjustment for several potential confounders. The association between serum zinc and incident metabolic syndrome was attenuated by adjustment for waist circumference, serum HDL cholesterol, or hypertension. Serum zinc was also directly associated with higher waist circumference and hypertension and inversely associated with HDL cholesterol at the 11 y examinations.

CONCLUSIONS

We found a direct association between serum zinc and incidence of metabolic syndrome in middle-aged and older eastern Finnish men. Further studies are warranted to explore the mechanisms.

GPR39 Zn(2+)-sensing receptor: a new target in antidepressant development?

Zinc is a trace element released from glutamatergic terminals, and modulates the pre- and postsynaptic areas, giving a diverse biological response. Zinc is a natural ligand that inhibits the N-methyl-d-aspartate (NMDA) receptor and regulates the excessive release of glutamate. Moreover, zinc exhibits an antidepressant-like profile, as demonstrated in both preclinical and clinical studies. Recent reports indicate that the GPR39 Zn(2+)-sensing receptor is an important target for zinc "transmission" (its activation modulates/induces diverse biochemical pathways involved in neuroprotection). Preclinical studies provide evidence that zinc deficiency leads to depressive-like behavior related to down-regulation of the GPR39 Zn(2+)-sensing receptor. Zinc binds to the GPR39 and triggers signals, leading to CRE-dependent gene transcription, resulting in increases in proteins such as brain-derived neurotrophic factor (BDNF), that plays a pivotal role in antidepressant action. Chronic administration of many antidepressants induces GPR39 up-regulation, which suggests that the Zn(2+)-sensing receptor may be considered as a new target for drug development in the field of depression.

Beverage from Coleus aromaticus reduces leptin levels and improves appetite rating in human volunteers

OBJECTIVE

Coleus aromaticus, commonly called country borage or Indian borage, is a perennial herb grown throughout the Indian subcontinent. Traditionally, the leaves of the plant are used as a cure for cold, cough, and fever as well as to relieve pain from skin irritations. However, the appetite-enhancing potential of the herb was unexplored. Based on the encouraging results of animal studies, this study was taken up to establish the appetite-enhancing potential of Coleus aromaticus in humans by evaluating its ready-to-drink beverage.

METHODS

A homogenous and healthy group of volunteers was selected. Ready-to-drink beverages based on the herb karpurvalli (Coleus aromaticus) containing three different concentrations (12% [sensorily optimized level], 18%, and 24%) of the herb juice and a placebo beverage were evaluated with the volunteers. The fasting and postprandial levels of plasma leptin were measured, and the appetite rating on a structured visual analog scale was obtained.

RESULTS

The study revealed a significant reduction in leptin levels with 12% juice, whereas a significant increase was seen after consumption of the beverage containing 24%. A similar pattern was obtained with the structured ratings.

CONCLUSION

The appetite-enhancing effect of the beverage was best when it contained the sensorily optimized level of karpurvalli juice and confirms the results obtained in animal study. To our knowledge, this is the first study validating the appetite-enhancing potential of the herb.