Doses Of Zinc Research Articles

Sublethal Doses of Zinc Protect Rat Neural Stem Cells Against Hypoxia Through Activation of the PI3K Pathway.

Cerebral infarction is one of the major causes of severe morbidity and mortality, and thus, research has focused on developing treatment options for this condition. Zinc (Zn) is an essential element in the central nervous system and has several neuroprotective effects in the brain. In this study, we examined the neuroprotective effects of Zn on neural stem cells (NSCs) exposed to hypoxia. After treatment with several concentrations of Zn, the viability of NSCs under hypoxic conditions was measured by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Trypan blue staining, and a lactate dehydrogenase assay. To evaluate the effect of Zn on the proliferation of NSCs, bromodeoxyuridine/5-bromo-2'-deoxyuridine (BrdU) labeling and colony formation assays were performed. Apoptosis was also examined in NSCs exposed to hypoxia with and without Zn treatment. In addition, a western blot analysis was performed to evaluate the effect of Zn on intracellular signaling proteins. NSC viability and proliferation were decreased under hypoxic conditions, but treatment with sublethal doses of Zn restored viability and proliferation. Sublethal doses of Zn reduced apoptosis caused by hypoxia, increased the expression levels of proteins related to the phosphatidylinositol-3 kinase (PI3K) pathway, and decreased the expression levels of proteins associated with neuronal cell death. These findings confirm that in vivo, sublethal doses of Zn protect NSCs against hypoxia through the activation of the PI3K pathway. Thus, Zn could be employed as a therapeutic option to protect NSCs in ischemic stroke.

Preferential mode of zinc and adherence to treatment: zinc syrup or zinc tablet

Background: Diarrhoea has evident itself among the leading causes of under-five childhood mortality globally as well as in India. Although the benefits of zinc supplementation in diarrhoea management have been established, there remain many barriers to the widespread implementation of this treatment strategy. In India, a very small proportion of children in need, 20 per cent in urban and merely 5 per cent in rural, have access to zinc supplementation. The study aimed to assess zinc adherence in the community and find out the preferential mode of zinc as tablet or syrup, to stick to the scheduled adherence.Methods: The proposed method of study is a simple household survey complimented by secondary research around the preference and usage of zinc and ORS among under five children, suffered from diarrhoea in the last 14 days preceding the survey date.Results: The study revealed that 95 per cent of the respondents preferred zinc syrup over zinc tablet for treatment of diarrhoea due to its ease to administer and palatable taste to children. Eighty nine per cent of the total urban and 62 per cent of total rural respondents received zinc in syrup form, indicating the preferred mode of zinc by service providers over tablets.Conclusions: It has been observed that the caregivers tend to give the complete dosage of zinc if it is available in the syrup form. However, it is important to generate evidence to understand the preferential mode of zinc; tablet or syrup in terms of administration of drug, its usage and its cost.

Zinc Supplementation for Promoting Growth in Children Under 5 years of age in Low- and Middle-income Countries: A Systematic Review

To study the effect of zinc supplementation in children under 5 years of age rom low- and middle-income countries (LMICs) on anthropometry and prevalence of malnutrition. Systematic review of randomized controlled trials and cluster randomized trials. Low- and middle-income countries. 63 trials with zinc supplementation, incorporating data on 27372 children. Trials conducted exclusively in specifically diseased participants and in children with severe acute malnutrition were excluded. Zinc supplementation, provided either as medicinal supplementation or through food fortification. (i) Anthropometry: weight, height, weight-for-height, mid-arm circumference, head circumference; (ii) Prevalence of malnutrition. There was no evidence of effect on height-for-age Z score at the end of supplementation period (25 trials; 9165 participants; MD= 0.00 Z; 95% CI -0.07, 0.07; P=0.98; moderate quality evidence) with significant heterogeneity (I² = 57%; P<0.001) related to dose and duration of zinc between trials. There was little or no effect on change in height-for-age Z score (13 trials; 8852 participants; MD= 0.11 Z; 95% CI -0.00, 0.21; P=0.05), but the heterogeneity was considerable (I²=94%; P<0.001). There was no evidence of effect on length (6303 participants; MD= 1.18 cm; 95% CI -0.63, 2.99 cm, P=0.20; moderate quality evidence; considerable heterogeneity, I²=99%) but a little positive effect on change in length (19 trials; 10783 participants; MD= 0.43 cm; 95% CI 0.16, 0.70, P=0.002; moderate quality evidence; considerable heterogeneity, I²=93%). There was no evidence of effect on weight-for-age Z score or change in weight-for-age Z score but a little positive effect on weight (19 trials; 8851 study participants; MD= 0.23 kg; 95% CI 0.03, 0.42; P=0.02; considerable heterogeneity, I²=91%) and change in weight (kg) (23 trials; 10143 study participants; MD= 0.11 kg; 95% CI 0.05, 0.17, P<0.001, substantial heterogeneity, I²=80%). There was no evidence of effect on weight-for-height Z score, and mid upper arm circumference at the end of supplementation period, but there was a little positive effect on change in MUAC from baseline (8 trials; 1724 participants; MD = 0.09 cm; 95% CI 0.01, 0.16; P=0.03; no heterogeneity, I²=0%). Head circumference in zinc supplemented group was marginally higher compared to control (2966 study participants; MD= 0.39 cm; 95% CI 0.03, 0.75; P=0.03; substantial heterogeneity, I²=67%). There was no evidence of benefit in stunting (10 trials; 11838 study participants; RR= 1.0; 95% CI 0.95, 1.06; P=0.89; Moderate Quality Evidence; no significant heterogeneity, I²=11%), wasting (7 trials; 8988 study participants; RR= 0.94; 95% CI 0.82, 1.06; P=0.31; Moderate Quality Evidence; no significant heterogeneity, I²=13%) or underweight (7 trials; 8677 study participants; RR= 1.08; 95% CI 0.96, 1.21; P=0.19; Moderate Quality Evidence; substantial heterogeneity, I²=73%). Available evidence suggests that zinc supplementation probably leads to little or no improvement in anthropometric indices and malnutrition (stunting, underweight and wasting) in children under five years of age in LMICs. Advocating zinc supplementation as a public health measure to improve growth, therefore appears unjustified in these settings with scarce resources.

Zinc supply methods and doses for corn

Deficiency of the micronutrient Zinc (Zn) is a limiting factor for corn productivity and its lack is a notorious factor in the Brazilian savannah. Current research, analyzing the best method and dose to be supplied to corn in the region, was performed on the experimental field of the Instituto Federal de Mato Grosso, campus Campo Novo do Parecis MT Brazil. Sowing occurred on the 11th March 2017, with corn variety NS90, and harvest on the 24th July 2017. Design consisted of randomized blocks, with a 2 x 5 factorial scheme, with 4 replications, or rather, 2 supply forms (application to soil and to leaves, at vegetative stage 4 – fourth leaf) and 5 doses of Zn (0; 0.25; 0.50; 0.75; 1.0 kg ha-1). Corn´s vegetative and reproductive characteristics were evaluated. Analysis of variance (F-test) and regression test were undertaken (p<0.05). Zn provided via leaf increased stalk diameter, insertion height and spike length. Reduction in the mass of one thousand grains and grain productivity occurred for increasing Zn doses. Zn is highly relevant for the development of corn and its supply provides significant responses to the above-mentioned variables.

Changes in Zinc Concentration as Influenced by Sesquioxide Under Different Moisture Regimes in Acidic Rice Soils of Eastern India

The availability of zinc (Zn) in soils is influenced by pH, organic matter content, clay particles and sesquioxides. We conducted laboratory incubation experiments on a rice-growing soil (Alfisol) to determine the effect of sesquioxide on zinc availability under different moisture regimes. Three different graded doses of zinc (0, 5 and 10 mg Zn/kg) were applied to soil containing sesquioxide and without sesquioxide under saturated and waterlogged conditions. The extractable zinc under 0.1 N HCl and 0.005 M DTPA was highest in the soil without sesquioxide and followed the order as: 0.1 N HCl-extractable Zn > 0.005 M DTPA. During the 35 days of incubation, highest values of 0.1 N HCl-extractable Zn and 0.005 M DTPA-extractable Zn were recorded in soil maintained at saturated compared with waterlogged conditions. The zinc availability in soil was reduced by 53 and 20% in sesquioxide-free soil and sesquioxide-containing soil, respectively, irrespective of zinc extractants. Higher dose of applied Zn resulted in a greater reduction in the Zn availability and indicated for split application of Zn to enhance the Zn supplying power of soil to greater extent.

Growth and yield response of cauliflower in different doses of zinc

Growth and yield response of cauliflower in different doses of zinc

Induction of lactation: an economic study of tool for dairy heifers with successive reproductive failures

ABSTRACT: The aim of this study was to evaluate the economic viability of the use of a lactation induction protocol in Holstein heifers. Were collected data of nutritional, reproductive and sanitary management pre and post-lactation period from 30 induction heifers (IG) and 30 pregnant heifers (CG). All animals were inseminated around 14 months of age and started lactation at 23±4 months. The animals of IG were heifers do not pregnant after two inseminations and natural service e were induced to lactation according to protocol: from the 1st to the 8th day, 30 mg of estradiol benzoate were administered daily, together with 300 mg of progesterone. From the 9th until the 14th, animals only received daily doses of 20 mg estradiol benzoate. On 16th day, 0.56 mg of sodium cloprostenol was administered and injections of 40 mg of dexamethasone sodium phosphate were administered daily from the 19th to the 21st day. On the 1st, 8th, 15th and 22nd day, the animals received a dose of sometribove zinc. The animals of CG were managed according to the farm routine. The costs of the CG during pre and post lactation (nutrition, sanitary, reproduction management) e were higher than the IG, however, when evaluating the economic viability due to lower milk production, the induced group did not leave profit in the first year of use. When comparing the lactation induction with the sale of animals that did not conceive and purchase of animals for replacement, this last scenario showed itself as a better alternative.

Induction of Cell Proliferation and Cell Death in Human Follicle Dermal Papilla Cells by Zinc Chloride

In the present investigation, the effects of zinc on the growth of human follicle dermal papilla cells were determined. A higher dose of zinc was found to significantly increase the proliferation of human follicle dermal papilla cells and the expression levels of cell cycle regulatory proteins. However, cell death, an increase in the apoptotic protein Bax, and caspase-3 activation were also observed in zinc-treated human follicle dermal papilla cells. The results from our present study suggest that the regulation of human follicle dermal papilla cells proliferation or death by zinc might be directly involved in hair regrowth in a narrow dose range.

Zinc Absorption from Micronutrient Powders Is Low in Bangladeshi Toddlers at Risk of Environmental Enteric Dysfunction and May Increase Dietary Zinc Requirements

ABSTRACTBackgroundEnvironmental enteric dysfunction (EED), a chronic inflammatory disorder of the small bowel, is suspected to impair absorption of micronutrients, including zinc.ObjectiveThe objective of this study was to compare zinc absorption from micronutrient powder (MNP) over a range of zinc doses in young children screened for EED with use of the lactulose:mannitol ratio (L:M).MethodsBangladeshi children aged 18–24 mo, grouped according to high and low L:M (≥0.09 and <0.09, respectively), were randomly assigned to MNP with 0, 5, 10, or 15 mg Zn/sachet (10 subjects per dose per L:M group). Over a day, fractional absorption of zinc was measured from an MNP-fortified meal and from unfortified meals with stable isotope tracers; total daily absorbed zinc (TAZ, milligrams per day) was determined as the primary outcome. Secondary outcomes included investigation of relations of TAZ to intake, to physiologic requirement, and to other variables, including biomarkers of systemic and intestinal inflammation, using nonlinear models. TAZ was also compared with published data on child zinc absorption.ResultsIn 74 subjects who completed the study, zinc absorption did not differ by L:M grouping. Most biomarkers of intestinal inflammation were elevated in both L:M groups. For combined L:M groups, mean ± SD TAZ for each MNP dose (0, 5, 10, and 15 mg/sachet) was 0.57 ± 0.30, 0.68 ± 0.31, 0.90 ± 0.43, and 1.0 ± 0.39 mg/d, respectively (P = 0.002), and exceeded the estimated physiologic requirement only for the 10- and 15-mg MNP doses. Zinc absorption was notably lower at all intake levels compared with published data (P < 0.0001) and was inversely related to serum α-1 acid glycoprotein and to fecal Entamoeba histolytica (P = 0.02).ConclusionResults indicate impaired absorption of zinc, which may predispose to zinc deficiency in young children with evidence of enteropathy. These findings suggest that current doses of zinc in MNP may be insufficient to yield zinc-related preventative benefits in similar settings. This study is registered at clinicaltrials.gov as NCT02758444.

Sustainability of Agro-Gray Soil to Pollution and Acidification, and its Biodiagnostics

The aim of investigations is to study the resistance of agro-gray heavy loamy soil to heavy metal pollution and acidification on the basis of determining corresponding parameters of buffering, as well as microbiological activity, as a biological diagnosis of fertility potential under stress conditions.The object of investigations is the agro-gray soil of different cultivation degrees: fertile and infertile. In fertile soil, the humus content in barren soil was 2.2-2.5 % and that in fertile soil was 5.4 %.A model of soil resistance to heavy metals and acidification has been developed. The low level of stability of the agro-gray soil appears when the maximum Langmuir adsorption value is less than 91 mM / kg for zinc, less than 104 mM / kg for copper, less than 93 mM / kg for lead, and less than 61 mM / kg for cadmium. The average level of stability is provided for zinc, copper and lead in the range from 91 to 143 mM / kg, 104 - 130 mM / kg and 61 - 132 mM / kg, respectively. A high level of soil stability is guaranteed if the maximum adsorption value exceeds 93 - 143 mM / kg. Bio diagnostics included a series of experiments with imitation of pollution and acidification. Soil pollution was modeled by adding 200 and 600 mg / kg of copper to it (experiment 1). In experiment 2, soil was polluted by cadmium at the rate of 10, 30 and 100 MAC. The exposition was 1, 10, 35 and 57 days.Acidification of the soil was simulated by adding dilute sulfuric acid at a rate of 0.018, 0.044, and 0.120 mM / l (experiment 3).In experiment 4, the effect of zinc on the activity of azotobacter in barren and fertile soil was studied. The dose of zinc was 50 and 100 mg / kg.It was established that when the content of humus is not less than 5 %, the average decrease in activity for all groups of microorganisms was not more than 20 % as compared with clean samples. When the humus content was below 3 %, the microbiological activity decreased by more than 30 %.

Preparation and Characterization of Sustained Released Zinc Citrate Encapsulated in Whey Protein Nanoparticles.

The use of milk proteins for drug delivery is a new trend in functional foods and pharmaceutical. Recently, researchers have focused on the utilization of whey proteins in the preparation of nanoparticle and carrier for drugs and micronutrients. The objectives of this paper were to use whey proteins isolate (WPI) nanoparticles for the encapsulation of zinc citrate micronutrients and characterization of the prepared nanoparticles. Nanoparticles were prepared from WPI with pH cycling and used for the encapsulation and sustained release of zinc citrate with three ratios (7, 14 and 28 mM) of zinc citrate per gram WPI. The particle size of the prepared nanoparticles was characterization and examined by transmission electron microscopy. The release of Zinc from the prepared nanoparticles was carried out using simulated gastric fluid at pH 1.2 using dialysis membranes, the amount of zinc citrate loaded whey protein (14.36 mg Zinc in 1 g WPI) within range of daily dose of zinc for healthy adults. The WPI nanoparticles were able to encapsulate efficiently zinc, with encapsulation efficiency that ranged between 99.79 and 96.31%. Zinc was highly released from the prepared nanoparticles in acidic media (pH 1.2). It can be concluded that WPI can be used as an effective vehicle for the protection and sustained release of zinc in food and pharmaceutical preparations.

High dosage of zinc modulates T-cells in a time-dependent manner within porcine gut-associated lymphatic tissue.

Zn serves as a powerful feed additive to reduce post-weaning diarrhoea in pigs. However, the mechanisms responsible for Zn-associated effects on the adaptive immune responses following feeding of a very high dosage of Zn remain elusive. In this study, we examined the T-cell response in gut-associated lymphatic tissues of seventy-two weaned piglets. Piglets received diets with 57 mg Zn/kg (low Zn concentration, LZn), 164 mg Zn/kg (medium Zn concentration, MZn) or 2425 mg Zn/kg (high Zn concentration, HZn) mg Zn/kg feed for 1, 2 or 4 weeks. We observed that feeding the HZn diet for 1 week increased the level of activated T-helper cells (CD4+ and CD8α dim) compared with feeding MZn and LZn (P<0·05). In addition, we observed higher transcript amounts of interferon γ and T-box 21 (TBET) in the HZn group compared with the MZn and LZn groups (P<0·05). A gene set enrichment analysis revealed an over-representation of genes associated with 'cytokine signalling in immune system'. Remarkably, feeding of a very high Zn dosage led to a switch in the immune response after 2 weeks. We detected higher relative cell counts of CD4+CD25high regulatory T-helper cells (P<0·05) and a higher expression of forkhead box P3 (FOXP3) transcripts (P<0·05). After 4 weeks of feeding a high-dosage Zn diet, the relative CD4+ T-cell count (P<0·05) and the relative CD8β + T-cell count (P<0·1) were reduced compared with the MZn group. We hypothesise that after 1 week the cellular T-helper 1 response is switched on and after 2 weeks it is switched off, leading to decreased numbers of T-cells.

Methodology of Applying Different Doses of Boron and Zinc in the Coating of Perennial Soybean Seeds

Methodology of Applying Different Doses of Boron and Zinc in the Coating of Perennial Soybean Seeds

CRESCIMENTO E TOLERÂNCIA DE MUDAS DE &lt;i&gt;Enterolobium contortisiliquum &lt;/i&gt;Vell. CULTIVADAS EM SOLO CONTAMINADO COM ZINCO

O zinco é um elemento essencial às plantas, mas quando presente em altas concentrações no solo pode se tornar tóxico ao metabolismo vegetal. O trabalho objetivou determinar o crescimento e tolerância de mudas de Enterolobium contortisiliquum Vell. cultivadas em solo contaminado com zinco. O experimento foi conduzido em casa de vegetação, em solo com 81% de argila, no delineamento inteiramente casualizado, com sete tratamentos, constituídos de doses de zinco (0, 100, 200, 300, 400, 500 e 600 mg kg-1) e oito repetições. Avaliou-se a altura de planta, diâmetro de colo, massa seca aérea, massa seca radicular, comprimento da raiz principal, área superficial específica, teor de Zn na parte aérea e radicular, coeficiente do impacto do teor relativo de zinco, índice de translocação e de tolerância. O coeficiente do impacto do teor relativo de zinco indicou tendência de menor translocação de Zn à parte aérea da muda até a dose de 300 mg de Zn kg-1 de solo. Os resultados evidenciaram que doses próximas a 200 mg de zinco kg-1 de solo argiloso estimulam a altura de planta, diâmetro do colo, a massa seca aérea e radicular das mudas de timbaúva. A timbaúva apresenta elevada tolerância ao zinco e por ser uma arbórea nativa adaptada às condições ambientais do Brasil pode ser indicada para revegetação de áreas contaminadas com a aplicação de até 600 mg de zinco kg-1 de solo argiloso.

Comparative Transcriptome Analysis of Pseudomonas putida KT2440 Revealed Its Response Mechanisms to Elevated Levels of Zinc Stress.

The whole-genome transcriptional response of Pseudomonas putida KT2440 to stress-inducing concentrations of zinc was analyzed in this study by RNA sequencing to thoroughly investigate the bacterial cell response to zinc toxicity. The data revealed that different levels of zinc stress strongly affected the transcription of genes from the following categories: metal transport genes, genes involved in membrane homeostasis, oxidative-stress-responding genes, and genes associated with basic cellular metabolism. At the lowest zinc dose, only several genes associated with metal transport and membrane homeostasis were strongly influenced. At the intermediate zinc dose, transcriptional changes of genes belonging to these two categories were highly pronounced. In addition, the intermediate zinc stress produced high levels of oxidative stress, and influenced amino acid metabolism and respiratory chains of P. putida. At the highest zinc dose, the induction of genes responsible for Fe–S cluster biogenesis was the most remarkable feature. Moreover, upregulation of glyoxylate cycle was observed. In summary, the adaptation of the cell envelope, the maintenance of metal homeostasis and intracellular redox status, and the transcriptional control of metabolism are the main elements of stress response, which facilitates the survival of P. putida KT2440 in zinc-polluted environments.

Uso de reguladores vegetais na propagação via estaquia de umbu-cajazeira

The umbu-cajazeira is one of the most exploited native fruits in the Brazilian semi-arid region, since its fruits are highly sought after. In this sense, the objective was to evaluate the treatment of stock plants with zinc and rooting of umbu-cajazeira cuttings. The experimental design was completely randomized, with four replications. The experiment was conducted in a completely randomized design, with nine treatments, with levels determined by the matrix Central Box Compound for the doses of zinc (0; 5.8; 30; 34.2 and 40 mg L-1) and combinations with AIB doses (0; 872,35; 3.000; 5.127,65 and 6000 mg L-1), and four replicates. Treatment of stock plants with zinc did not affect the percentage of cuttings sprouts, number, length and diameter of shoots, rooting and dry mass production of umbu-cajazeira cuttings; Indolbutyric acid directly influences the rooting of umbu-cajazeira cuttings, and the maximum concentration of 6000 mg L-1 of IBA provides the highest percentages of adventitious rooting, with 43.75% of rooted cuttings.

Importance of Zinc for Arabica Coffee and Its Effects on the Chemical Composition of Raw Grain and Beverage Quality

Zinc is essential for the synthesis of amino acids, carbohydrates, and proteins, which are directly related to the chemical composition of raw coffee (Coffea arabica L.) beans, and it may influence the quality of the beverage. This study aimed at evaluating the influence of Zn doses on the chemical composition of coffee beans and beverage quality. Increased Zn availability in the growth medium maximized attributes related to beverage quality, such as polyphenol oxidase activity, color index, and contents of sucrose, caffeine, and trigonelline, reaching maximum values in plants with Zn leaf contents within the sufficiency range of 8.0 to 12.7 mg kg−1. Zinc doses lower or higher than the one that provided maximum quality (∼2 μmol L−1 in nutrient solution) increased the attributes related to loss of beverage quality, such as content of total phenols, 5‐caffeoylquinic acid, leached K, and electrical conductivity. Zinc supply influences the quality of coffee beans, having a positive effect on polyphenol oxidase activity, color index, and contents of sucrose, caffeine, and trigonelline. Adequate Zn doses reduce total phenol content, 5‐caffeoylquinic acid, leached K, and electrical conductivity. The leaf contents, which related to the minimum or maximum points of the quality attributes studied, varied between 8.0 and 12.7 mg Zn kg−1.

A dynamic model for predicting growth in zinc-deficient stunted infants given supplemental zinc

Zinc deficiency limits infant growth and increases susceptibility to infections, which further compromises growth. Zinc supplementation improves the growth of zinc-deficient stunted infants, but the amount, frequency, and duration of zinc supplementation required to restore growth in an individual child is unknown. A dynamic model of zinc metabolism that predicts changes in weight and length of zinc-deficient, stunted infants with dietary zinc would be useful to define effective zinc supplementation regimens. The aims of this study were to develop a dynamic model for zinc metabolism in stunted, zinc-deficient infants and to use that model to predict the growth response when those infants are given zinc supplements. A model of zinc metabolism was developed using data on zinc kinetics, tissue zinc, and growth requirements for healthy 9-mo-old infants. The kinetic model was converted to a dynamic model by replacing the rate constants for zinc absorption and excretion with functions for these processes that change with zinc intake. Predictions of the dynamic model, parameterized for zinc-deficient, stunted infants, were compared with the results of 5 published zinc intervention trials. The model was then used to predict the results for zinc supplementation regimes that varied in the amount, frequency, and duration of zinc dosing. Model predictions agreed with published changes in plasma zinc after zinc supplementation. Predictions of weight and length agreed with 2 studies, but overpredicted values from a third study in which other nutrient deficiencies may have been growth limiting; the model predicted that zinc absorption was impaired in that study. The model suggests that frequent, smaller doses (5-10 mg Zn/d) are more effective for increasing growth in stunted, zinc-deficient 9-mo-old infants than are larger, less-frequent doses. The dose amount affects the duration of dosing necessary to restore and maintain plasma zinc concentration and growth.

Mineral enrichment in carrot with different sources and doses of zinc

ABSTRACT Zinc (Zn) deficiency in soil and plants and its low nutritional status in the population encourage studies on enrichment of agricultural products. Carrot has potential to enrichment because it is a commonly consumed vegetable. The objective of this study was to evaluate Zn sources (ZnO, ZnSO4, or ZnEDTA) and doses (0, 5, 10, 20, and 30 mg dm-3) applied to the soil to increase the concentration of this mineral in the carrot edible part. Zinc sulfate was the most suitable source for this role because it had a higher accumulation with the increase of treatment dose. The best dose was 19.45 mg dm-3 of ZnSO4, which resulted the highest content of Zn in carrots. Moreover, this treatment increased Zn in the root by seven times compared with the control. The low production cost of Zn enrichment of carrots makes them a potential vegetable for the deficiency reduction of this micronutrient in the population nutrition.

Zinc as a therapy in a rat model of autism prenatally induced by valproic acid

Autism is characterized by numerous behavioral impairments, such as in communication, socialization and cognition. Recent studies have suggested that valproic acid (VPA), an anti-epileptic drug with teratogenic activity, is related to autism. In rodents, VPA exposure during pregnancy induces autistic-like effects. Exposure to VPA may alter zinc metabolism resulting in a transient deficiency of zinc. Therefore, we selected zinc as a prenatal treatment to prevent VPA-induced impairments in a rat model of autism. Wistar female rats received either saline solution or VPA (400 mg/kg, i.p) on gestational day (GD) 12.5. To test the zinc supplementation effect, after 1 h of treatment with saline or VPA, a dose of zinc (2 mg/kg, s.c.) was injected. The offspring were tested for abnormal communication behaviors with an ultrasound vocalization task on postnatal day (PND) 11, repetitive behaviors and cognitive ability with a T-maze task on PND 29, and social interaction with a play behavior task on PND 30. Tyrosine hydroxylase protein (TH) expression was evaluated in the striatum. Prenatal VPA decreased ultrasonic vocalization, induced repetitive/restricted behaviors and cognitive inflexibility, impaired socialization, and reduced striatal TH levels compared with control group. Zinc treatment reduced VPA-induced autistic-like behaviors. However, we found no evidence of an effect of zinc on the VPA-induced reduction in TH expression. The persistence of low TH expression in the VPA-Zn group suggests that Zn-induced behavioral improvement in autistic rats may not depend on TH activity.