Assessment of trace element and mineral levels in students from Turkmenistan in comparison to Iran and Russia.

THE OBJECTIVE: Of the present study was to assess essential trace element and mineral levels in serum, hair, and urine of healthy first-year students from Turkmenistan (n = 73) in comparison to students from Iran (n = 78) or Russia (n = 95). MATERIALS AND METHODS: Examination of foreign students was performed within two days after arrival to Russia during medical examination prior admission to RUDN University. Serum, hair, and urine trace element and mineral levels were assessed with inductively coupled plasma-mass spectrometry (ICP-MS). RESULTS: The data demonstrate that the levels of trace elements and minerals in students from Turkmenistan share high similarity to elemental profiles of students from Iran. In comparison to students from Russia, subjects originating from Iran and Turkmenistan are characterized by lower serum cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), molybdenum (Mo), selenium (Se), vanadium (V), zinc (Zn) levels, higher urinary Cr, Cu, Fe, Mn, V, and Zn, lower urinary Co and hair Mo, Se, and Zn content. Concomitantly, students from Turkmenistan were characterized by lower urinary Cr and Cu, serum Cu and V levels, higher circulating Zn concentration, as well as the lower hair Cr, Cu, iodine (I) and magnesium (Mg) content in comparison to Iranian subjects. The discriminant analysis demonstrated that hair, serum, and urinary trace element and mineral levels contributed to complete discrimination between the groups of students from different countries. CONCLUSIONS: The high similarity of trace element and mineral status of students from Turkmenistan and Iran is expected to be mediated by similar geochemical conditions in the bordering countries.

Hair and Serum Trace Element and Mineral Levels Profiles in Women with Premenopausal and Postmenopausal Osteoporosis.

The objective of the present study was to evaluate serum and hair trace element and mineral levels in women with osteoporosis, as well as to estimate the impact of menopausal status on the profile of trace element and mineral status in women with osteoporosis. 207 women with diagnosed osteoporosis 22-85 years-of-age, and 197 healthy women of the respective age participated in the present study. Analysis of the levels of mineral and trace element in hair and serum samples was performed by inductively-coupled plasma mass-spectrometry (ICP-MS). Women with osteoporosis were characterized by significantly lower hair Ca, Mg, Co, I, Li, and Mn levels, as well as serum Ca, Mg, Co, Fe, V, and Zn concentrations compared to women in the control group. After additional grouping according to menopausal status, the lowest hair Ca and Mg content was observed in postmenopausal osteoporotic women, whereas serum Ca and Mg concentrations were the lowest in premenopausal osteoporotic women. Hair Co, Mn, and Zn levels in postmenopausal osteoporotic women were lower than in healthy postmenopausal women. The lowest circulating Zn levels were observed in osteoporotic postmenopausal women. Taken together, decreased hair and serum levels in osteoporotic women are indicative of increased risk of Ca, Mg, Co, and Zn deficiency in women with osteoporosis. In turn, alterations in hair trace element and mineral levels in osteoporosis are more profound in postmenopausal women. Hypothetically, improvement in trace element and mineral metabolism especially in postmenopausal women may be considered as a potential strategy for mitigating osteoporosis.

Alterations in serum amino acid profiles in children with attention deficit/hyperactivity disorder.

The objective of the present study was to evaluate the circulating serum amino acid levels in children with attention deficit/hyperactivity disorder (ADHD). A total of 71 children with untreated ADHD and 31 neurotypical controls aged 7-14 years old were examined. Serum amino acid levels were evaluated using high-performance liquid chromatography (HPLC) with UV-detection. Laboratory quality control was performed with reference materials of human plasma amino acid levels. The obtained data demonstrated that children with ADHD were characterized by 29, 10 and 20% lower serum histidine (His), glutamine (Gln) and proline (Pro) levels compared with neurotypical children, respectively. In contrast, circulating aspartate (Asp), glutamate (Glu) and hydroxyproline (Hypro) levels exceeded the respective control values by 7, 7 and 42%. Correspondingly, the Gln-to-Glu and Pro-to-Hypro ratios were 28% and 49%, respectively, lower in ADHD cases compared with the controls. Total Gln/Glu levels were also significantly lower in ADHD patients. No significant group differences were observed between the groups in the other amino acids analyzed, including phenylalanine. Multiple linear regression analysis revealed significant associations between circulating serum Gln, lysine (Lys) (both negative) and Glu (positive) levels with total ADHD Rating Scale-IV scores. The observed alterations in Pro/Hypro and Gln/Glu levels and ratios are likely associated with the coexisting connective tissue pathology and alterations in glutamatergic neurotransmission in ADHD, respectively. Altered circulating levels of His, Lys and Asp may also be implicated in ADHD pathogenesis. However, further in vivo and in vitro studies are required in order to investigate the detailed mechanisms linking amino acid metabolism with ADHD pathogenesis.

Magnesium Status in Children with Attention-Deficit/Hyperactivity Disorder and/or Autism Spectrum Disorder.

OBJECTIVE: The objective of this study was to assess serum, hair, and urinary magnesium (Mg) levels in children with attention-deficit/ hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and both ASD and ADHD to reveal potential interactive effects. METHODS: A total of 148 boys aged 4-9 years old were enrolled in this study, including 44 children with ADHD, 40 pediatric patients with ASD, 32 patients with both ADHD and ASD, as well as 32 healthy neurotypical children. Hair, serum, and urinary Mg levels were assessed using inductively-coupled plasma mass spectrometry (ICP-MS). Laboratory quality control was performed using certified reference materials of human hair, plasma, and urine. RESULTS: No significant group difference in serum Mg levels was observed. Mg content in hair was found to be reduced in children with ADHD and ADHD+ASD compared to that in healthy controls by 11% and 15%, respectively. Urinary Mg levels in children with ADHD+ASD exceeded the control, ADHD, and ASD values by 51, 76, and 65%, respectively. Factorial analysis revealed significant contribution of ADHD to hair and urinary Mg levels. Multiple regression analysis demonstrated that hair and urinary Mg levels were considered as significant predictors of neurodevelopmental disorder complexity. CONCLUSION: We propose that impaired Mg status may provide a link between ADHD and ASD.

Arsenic, cadmium, mercury, and lead levels in hair and urine in first-year RUDN University students of different geographic origins.

The objective of the present study was to assess the markers of arsenic, cadmium, mercury, and lead exposure in first-year RUDN University students of different geographic origins. A total of 274 first-year students of the RUDN University originating from Russia (n = 65), Asia (n = 57), Middle East (n = 84), Africa (n = 40), and Latin America (n = 28) were enrolled in the present study. Evaluation of As, Cd, Hg, and Pb levels in urine and hair was performed using inductively coupled plasma-mass spectrometry. The obtained data demonstrate that hair As levels in foreign students exceed that in Russian examinees. The highest Cd and Pb levels were detected in subjects from Africa and Latin America, whereas hair Hg content was significantly higher in Latin America students. Urinary Cd levels in foreign students exceeded those in Russian counterparts. In turn, the highest Hg concentration in urine was revealed in students originating from Middle East and especially Latin America. Urinary Pb levels were found to be the highest in students from Africa. Multiple regression analysis demonstrated that Asian, African, and Latin American origins were considered as a significant predictor of hair Hg content. Higher urinary Hg levels were associated with Asia, Middle East, and Latin American origins. Prior habitation in Africa and Asia was considered as predictor of higher hair Pb and urinary Cd levels. The observed difference may be indicative of geographic difference in toxic metal exposure patterns.

Hair trace element concentrations in autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD).

BACKGROUND: The existing data demonstrate that alteration of trace element and mineral status in children with neurodevelopmental disorders including ASD and ADHD. However, comparative analysis of the specific patterns of trace element and mineral metabolism in children with ASD and ADHD was not performed. Therefore, the primary objective of the present study was to assess hair trace element and mineral levels in boys with ADHD, ASD, as well as ADHD with ASD. METHODS: Boys with ADHD (n = 52), ASD (n = 53), both ADHD and ASD (n = 52), as well as neurotypical controls (n = 52) were examined. Hair analysis was performed using inductively-coupled plasma mass-spectrometry. RESULTS: The obtained data demonstrate that hair Co, Mg, Mn, and V levels were significantly reduced in children with ADHD and ASD, and especially in boys with ADHD + ASD. Hair Zn was found to be reduced by 20% (p = 0.009) only in children with ADHD + ASD as compared to healthy controls. Factor analysis demonstrated that ASD was associated with significant alteration of hair Co, Fe, Mg, Mn, and V levels, whereas impaired hair Mg, Mn, and Zn content was also significantly associated with ADHD. In regression models hair Zn and Mg were negatively associated with severity of neurodevelopmental disorders. The revealed similarity of trace element and mineral disturbances in ASD and ADHD may be indicative of certain similar pathogenetic features. CONCLUSION: The obtained data support the hypothesis that trace elements and minerals, namely Mg, Mn, and Zn, may play a significant role in development of both ADHD and ASD. Improvement of Mg, Mn, and Zn status in children with ASD and ADHD may be considered as a nutritional strategy for improvement of neurodevelopmental disturbances, although clinical trials and experimental studies are highly required to support this hypothesis.

ICP-MS Assessment of Hair Essential Trace Elements and Minerals in Russian Preschool and Primary School Children with Attention-Deficit/Hyperactivity Disorder (ADHD).

The objective of the present study was to investigate the relationship between hair essential trace element and mineral content and ADHD in preschool (4-6 years old) and primary school children (6-10 years old) in relation to age and gender. Hair essential trace element and mineral content in 90 Russian children with ADHD and 90 age- and gender-matched neurotypical controls were assessed using inductively coupled plasma mass-spectrometry after microwave digestion. The obtained data demonstrate that hair Co, Cu, Mn, Si, and Zn contents in ADHD children was significantly reduced by 18%, 10%, 27%, 16%, and 19% as compared to the control values, respectively. The most significant decrease in children with ADHD was observed for hair Mg levels, being 29% lower than those in neurotypical children. After adjustment for age and gender, the observed difference in hair element content was more characteristic for preschool children and girls, respectively. Multiple linear regression analysis demonstrated that in a crude model (hair element levels as predictors), only hair Zn content was significantly inversely associated with ADHD (ß = - 0.169; p = 0.025). Adjustment for anthropometric parameters (model 2) did not increase the predictive ability of the model, although it improved the association between hair Zn and ADHD in children (ß = - 0.194; p = 0.014). Hypothetically, the observed alterations may at least partially contribute to neurobehavioral disturbances in children with ADHD. Moreover, the results of the present study raise the question about the potential benefits of Zn and Mg supplementation in children with ADHD. However, further detailed studies are required to investigate micronutrient deficiencies in ADHD.

Serum zinc, copper, zinc-to-copper ratio, and other essential elements and minerals in children with attention deficit/hyperactivity disorder (ADHD).

BACKGROUND: Essential trace elements and minerals play a significant role in neurodevelopment. Although certain studies demonstrated impaired essential trace element and mineral status in children with ADHD, the existing data are insufficient. The objective of the present study was to assess serum trace element and mineral levels in children with ADHD. METHODS: Serum trace element and mineral levels in 68 children with ADHD and 68 neurotypical controls were assessed using ICP-MS at NexION 300D (PerkinElmer Inc., USA) equipped with ESI SC-2 DX4 autosampler (Elemental Scientific Inc., USA). RESULTS: Serum Cr, Mg, and Zn levels in children with ADHD were 21 % (p = 0.010), 4 % (p = 0.005), and 7 % (p = 0. 001) lower as compared to the healthy controls, respectively. In turn, serum Cu/Zn values were 11 % higher than those in the control group. Age and gender had a significant impact on serum element levels in ADHD. Particularly, preschool children were characterized by significantly increased Cu (+8 %; p = 0.034), and Cu/Zn (+19 %; p < 0.001) values, whereas serum Zn (-9 %; p = 0.004) level was decreased. In primary school-aged children only 6 % (p = 0.007) lower Mg levels were observed. Both boys and girls with ADHD were characterized by 8 % (p = 0.016) lower serum Zn levels and 10 % (p = 0.049) higher Cu/Zn values when compared to neurotypical girls. Boys with ADHD also had significantly higher Cu/Zn, exceeding the respective control values by 12 % (p = 0.021), predominantly due to a 7 % (p = 0.035) decrease in serum Zn. Serum Mg levels were also found to be significantly lower than those in neurotypical children by 5 % (p = 0.007). In adjusted regression models serum Cr (ß=-0.234; p = 0.009) and Cu/Zn (ß = 0.245; p = 0.029) values were significantly associated with ADHD, respectively. Two-way ANOVA revealed a significant impact of ADHD on Cr, Mg, Zn, and Cu/Zn, whereas age was associated with Cu, I, Mg, Mo, and Cu/Zn, whereas gender accounted only for variability in serum Mn levels. Principal component analysis (PCA) also revealed significant contributions of Mg, Zn, and Cu/Zn values to ADHD variability. CONCLUSIONS: Hypothetically, the observed decrease of essential trace elements, namely Mg and Zn, and elevation of Cu/Zn may significantly contribute to the risk of ADHD or its severity and/or comorbidity.

The efficiency of Governmental and WFP UN Programs for improvement of nutritional status in Tajik schoolchildren as assessed by dietary intake and hair trace element content.

BACKGROUND: The objective of the study was to assess hair trace element and mineral content in children undergoing WFP UN and the governmental programs of school nutrition in Tajikistan. METHODS: WFP program included provision or wheat flour fortified with micronutrients including Fe and Zn, and iodized salt, whereas within the governmental program hot meals were provided. A total of 202 children studying in schools that were not (Type 1, n = 100) or were involved in dietary intervention programs (Type 2, n = 102). Food and hair trace element content was assessed using ICP-MS. RESULTS: Daily intake of Fe, I, Zn, B, Co, Mg, Si, and Sr in Type 2 schools was more than 2.5, 12, 4, 2.9, 2.6, 2, 3, and 2-fold higher than that in Type 1 schools. Correspondingly, anthropometric parameters in children from Type 2 schools exceeded the control values. Surprisingly, no significant difference in hair iodine levels was detected. Hair analysis demonstrated a significant increase in hair Ca, Mg, Na, Co, Cr, Cu, Fe, Li, Mn, Se, V, Zn content. Certain toxic elements including Al, As, and Be were also characterized by an increase in Type 2 schools. At the same time, nutritional intervention was associated with a significant decrease in hair B, Hg, and Sn levels. CONCLUSIONS: Nutritional intervention within WFP and the governmental program was effective in increasing essential trace element supply in Tajik schoolchildren. However, further studies including a detailed assessment of nutritional and health status with a special focus on iodine and thyroid functioning are required.

Cobalt in athletes: hypoxia and doping - new crossroads.

Cobalt is an essential trace element that is known to mimic hypoxia and hypoxic training. Inorganic Co compounds are capable of Hypoxia-inducible factor-1 (HIF-1) activation, resulting in up-regulation of gene expression including erythropoietin (Epo). Experimental studies have demonstrated that Co treatment may increase hypoxic tolerance of different tissues, improve muscle metabolism and exercise performance. Other mechanisms may also involve modulation of steroid hormone and iron metabolism. Based on these experimental studies, in 2017 inorganic cobalt compounds were added into the World Anti-Doping Agency (WADA) prohibited list as doping agents. However, the existing data on beneficial effects of cobalt on exercise performance in athletes are scarce. Similarly, only experimental studies demonstrated exercise-induced decrease in tissue Co levels, whereas human data are inconsistent. In addition, multiple studies have demonstrated that excessive Co intake may be toxic due to prooxidant, proinflammatory, and proapoptotic activity. Therefore, monitoring of Co deficiency and overload is required to prevent potential health hazards in athletes. At the same time, modulation of Co status should be performed through supplementation avoiding excessive doses of inorganic cobalt that are used for doping and are accompanied by adverse health effects of metal toxicity.

Assessing the boron nutritional status by analyzing its cummulative frequency distribution in the hair and whole blood.

Boron is a non-essential ubiquitous trace element in the human body. The aim of this study was to assess boron nutritional status by analyzing boron frequency distribution in the long-term biological indicator tissue of hair and the short-term biological indicator of whole blood. Hair samples were analyzed in 727 apparently healthy subjects (263 ♂ and 464 ♀) and the whole blood boron was analyzed in the random subsample of them (80 ♂ and 152 ♀). Samples were analyzed by the ICP-MS at the Center for Biotic Medicine, Moscow, Russia. The adequate reference range for hair boron concentration was (µg∙g-1) 0.771- 6.510 for men and distinctly lower 0.472-3.89 for women; there was no detectable difference in the whole blood boron for the adequate reference range between men (0.020-.078) and women (0019-0.062). Boron may play an essential role in the metabolism of the connective tissue of the biological bone matrix.

Hair concentration of essential trace elements in adult non-exposed Russian population.

Appropriate reference values of hair trace element content are required for correct interpretation of biomonitoring data. The primary objective of the current study was to estimate the reference values of selected essential trace elements in hair of adult Russian population. Involved in current investigation were 7256 occupationally non-exposed adults aged from 20 to 60 years and living in the European part of Russia. Occipital hair essential metal and metalloid (Co, Cr, Cu, Fe, Mn, Se, V, Zn) content was estimated using inductively coupled plasma mass spectrometry. The reference ranges were calculated in accordance with the International Union of Pure and Applied Chemistry (IUPAC) recommendations. Women were characterized by 55, 18, 58, and 7% higher values of hair Co, Cu, Mn, and Zn content as compared to the values observed in men. At the same time, hair Cr, Fe, Se, and V concentration in men significantly exceeded the respective female values by 65, 13, 20, and 56%. Consequently, the reference ranges of essential hair trace elements content should be separately calculated for both men and women. The obtained reference ranges for hair Co, Cr, Cu, Fe, Mn, Se, V, and Zn in men were 0.11-0.67, 0.007-0.045, 10.4-22.6, 11.1-40.5, 0.24-1.05, 0.089-0.480, 0.014-0.083, and 125.7-262.8 µg/g, respectively. The respective values estimated for women were 0.06-0.40, 0.011-0.085, 12.1-44.5, 8.9-25.6, 0.32-2.05, 0.094-0.504, 0.010-0.056, and 140.0-315.1 µg/g. The reference ranges for hair Co (0.07-0.50), Cr (0.009-0.073), Cu (11.8-29.2), Fe (9.6-31.5), Mn (0.29-1.76), Se (0.093-0.482), V (0.011-0.069), and Zn (134.7-301.9) content (µg/g) in the general cohort were also calculated.

Reference values of hair toxic trace elements content in occupationally non-exposed Russian population.

A total of 5908 occupationally non-exposed adults (4384 women and 1524 men) living in Moscow and Moscow region were involved in the current investigation. Hair Al, As, Be, Bi, Cd, Hg, Li, Ni, Pb, Sn, and Sr content was estimated by inductively-coupled plasma mass spectrometry using NexION 300D. Men are characterized by significantly higher hair Al, As, Cd, Hg, Li, and Pb content. At the same time, hair levels of Bi, Ni, Sn, and Sr were significantly higher in women. Consequently, the reference ranges were estimated for male, female, and general cohort as coverage intervals in accordance with IUPAC recommendations.

Effect of short-term zinc supplementation on zinc and selenium tissue distribution and serum antioxidant enzymes.

BACKGROUND: A significant association between Zn and Se homeostasis exists. At the same time, data on the influence of zinc supplementation on selenium distribution in organs and tissues seem to be absent. Therefore, the primary objective of the current study is to investigate the influence of zinc asparaginate supplementation on zinc and selenium distribution and serum superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity in Wistar rats. METHODS: 36 rats were used in the experiment. The duration of the experiment was 7 and 14 days in the first and second series, respectively. The rats in Group I were used as the control ones. Animals in Groups II and III daily obtained zinc asparaginate (ZnA) in the doses of 5 and 15 mg/kg weight, respectively. Zinc and selenium content in liver, kidneys, heart, muscle, serum and hair was assessed using inductively coupled plasma mass spectrometry. Serum SOD and GPx activity was analysed spectrophotometrically using Randox kits. RESULTS: Intragastric administration of zinc asparaginate significantly increased liver, kidney, and serum zinc content without affecting skeletal and cardiac muscle levels. Zinc supplementation also stimulated selenium retention in the rats' organs. Moreover, a significant positive correlation between zinc and selenium content was observed. Finally, zinc asparaginate treatment has been shown to modulate serum GPx but not SOD activity. CONCLUSIONS: The obtained data indicate that zinc-induced increase in GPx activity may be mediated through modulation of selenium status. However, future studies are required to estimate the exact mechanisms of zinc and selenium interplay.

Zinc asparaginate supplementation induces redistribution of toxic trace elements in rat tissues and organs.

The primary objective of the current study was the investigation of the influence of zinc asparaginate supplementation for 7 and 14 days on toxic metal and metalloid content in rat organs and tissues. Rats obtained zinc asparaginate in doses of 5 and 15 mg/kg/day for 7 and 14 days. At the end of the experiment rat tissues and organs (liver, kidney, heart, m. gastrocnemius, serum, and hair) were collected for subsequent analysis. Estimation of Zn, Al, As, Li, Ni, Sn, Sr content in the harvested organs was performed using inductively coupled plasma mass spectrometry at NexION 300D. The obtained data showed that intragastric administration of zinc significantly increased liver, kidney and serum zinc concentrations. Seven-day zinc treatment significantly affected the toxic trace element content in the animals' organs. Zinc supplementation significantly decreased particularly liver aluminium, nickel, and tin content, whereas lead tended to increase. Zinc-induced changes in kidney metal content were characterized by elevated lithium and decreased nickel concentration. Zinc-induced alteration of myocardical toxic element content was multidirectional. Muscle aluminium and lead concentration were reduced in response to zinc supplementation. At the same time, serum and hair toxic element concentrations remained relatively stable after 7-day zinc treatment. Zinc asparaginate treatment of 14 days significantly depressed liver and elevated kidney lithium content, whereas a significant zinc-associated decrease was detected in kidney strontium content. Zinc supplementation for 14 days resulted also in multidirectional changes in the content of heart toxic elements. At the same time, significant zinc-associated decrease in muscle lithium and nickel levels was observed. Fourteen-day zinc treatment resulted in significantly increased serum arsenic and tin concentrations, whereas hair trace element content remained relatively stable. Generally, the obtained data indicate a significant redistribution of toxic metals in the animal organism under zinc supplementation.

The influence of physical activity on hair toxic and essential trace element content in male and female students.

The primary aim of the current study is to estimate the effect of different physical activity levels on hair trace element content in male and female students. A total of 113 students (59 women and 54 men) of P. G. Demidov Yaroslavl State University (Yaroslavl, Russia) took part in the current investigation. According to the level of the physical activity, all students were divided into three groups: high, medium, and low physical activity. Essential and toxic metal content (µg/g) in hair samples was assessed by inductively coupled plasma mass spectrometry using NexION 300D + NWR213 (Perkin-Elmer, USA). The obtained data show that hair iodine, zinc, arsenic, nickel, and tin levels are not related to physical activity in male and female students. At the same time, increased physical activity is associated with decreased hair copper, vanadium, bismuth, and mercury content in comparison to the low physical activity groups. Students with higher physical activity are also characterized by significantly higher hair cobalt, iron, manganese, selenium, cadmium, lithium, and lead concentrations. Finally, statistical analysis has revealed maximal gender differences in hair trace element content in the high physical activity groups, whereas in the low activity groups, the hair metal concentrations were nearly similar in females and males.