Trace elements differences in the depression sensitive and resilient rat models.

The etiology and pathophysiology of depressive disorders remain unclear. Increasing evidences have demonstrated that trace elements such as zinc, magnesium, iron, calcium, selenium, manganese and chromium play vital roles in depressive symptoms. We used a Chronic Unpredictable Mild Stress (CUMS) model to simulate social pressure in rat model and compared the levels of trace elements in the plasma and brain. The concentrations trace elements were evaluated using inductively coupled plasma mass spectrometry or inductively coupled plasma-atomic emission spectrometry. In the CUMS model, 57% (12/21) of rats showed no significant decrease in sucrose preference and were grouped as CUMS-resilient; otherwise, CUMS-sensitive. The resilient group had higher levels of iron, sodium, sulfur, manganese and cobalt than the sensitive group in the brain samples (P < 0.05). The sensitive group had lower levels of calcium, potassium, sulfur, selenium and cobalt than the resilient groups, in the plasma samples. The higher levels of iron, calcium, selenium, manganese and cobalt in the resilient group indicated these trace elements might be protective against the development of depressive symptoms in response to stress.

Chinese children with autism: A multiple chemical elements profile in erythrocytes.

Several lines of evidence suggested that abnormal levels of certain chemical elements may contribute to the development of autism spectrum disorders (ASD). The present work aimed to investigate the multiple chemical elements profile in the erythrocytes of autistic versus typically developing children (TDC) of China. Analyses were carried out to explore the possible association between levels of elements and the risk as well as the severity of ASD. Erythrocyte levels of 11 elements (32%) among 34 detected elements in autistic group were significantly different from those in the TDC group. To our knowledge, this is the first study which compared the levels of rare earth elements in erythrocytes between children with or without ASD. Five elements including Pb, Na, Ca, Sb, and La are associated with the Childhood Autism Rating Scale (CARS) total score. Also, a series of tendencies were found in this research which was believed to affect auditory response, taste, smell, and touch, as well as fear or nervousness. It can be concluded that Chinese autistic children suffer from multi-chemical element imbalances which involves a complex combination of genetic and environmental factors. The results showed a significant correlation between abnormal levels of several chemical elements and the severity of the autistic syndrome. LAY SUMMARY: It is suggested that abnormal levels of some chemical elements may contribute to the development of autism spectrum disorders (ASD). In this work, the impact of element imbalances on the risk and severity of ASD was investigated, focusing on the analysis of abnormal levels of the multi-chemical elements profile in erythrocytes compared with typically developing children. Furthermore, the results showed a significant correlation between abnormal levels of several chemical elements and the severity of the autistic syndrome. Autism Res 2018, 11: 834-845. © 2018 International Society for Autism Research, Wiley Periodicals, Inc.

[Measurement and analysis of oxidative stress-related elements in blood components of chronic unpredictable mild stress rats].

OBJECTIVE: To study the effects of chronic unpredictable mild stress (CUMS) on the concentrations and distribution of elements related to oxidative stress in plasma and erythrocyte. METHODS: The rats were randomly divided into two groups, CUMS group and the control. The CUMS group received 28 days stress. Then 17 kinds of elements in plasma and erythrocyte were detected and the correlation ships between elements were analysed, then make comparison between two groups. RESULTS: The concentrations of Mo and B in plasma and Se in erythrocyte were higher in CUMS group than control (P <0. 05). The levels of Sn, Cr, Th and T1 in plasma as well as Mn and Pb in erythrocyte were lower in CUMS group (P < 0. 05). The strength and direction of correlation ships between elements were changed in CUMS group. There had a negative correlation with Fe in plasma in control (r = - 0. 581, P = 0. 018), but a positive correlation in CUMS (r = 0. 473, P = 0. 035), the same with Th-Mg (control: r = - 0. 610, P = 0. 012; CUMS: r = 0. 596, P = 0. 006). CONCLUSION: Concentrations and distribution of elements related to oxidative stress are changedby CUMS, most of the elements increased are related to anti-oxidative stress, while the reduced elements are prooxidative stress.

Manifestation of the Se, Cd and Mo levels in different components of the peripheral blood of Sprague-Dawley rats poisoned via the respiratory tract.

This study aimed to explore the effects of exogenous element exposure via the respiratory tract on the Se, Cd and Mo concentrations in different components of the peripheral blood in rats as well as to determine the correlations of the three trace elements concentrations among the components. The Sprague-Dawley rats were randomly divided into a control group and several experimental groups treated with different doses. The rats were exposed to a mixed trace element solution through 10 days of intratracheal instillation. The whole blood of all rats was collected and separated into three parts with Percoll density gradient centrifugation. The Se, Cd and Mo levels in whole blood, plasma, red blood cells (RBCs) and peripheral blood mononuclear cells (PBMCs) were determined by inductively coupled plasma mass spectrometry. The concentrations of the three trace elements increased together with the increase of the given doses (P<0.05), except Cd and Mo in the PBMCs. The three trace elements lacked linearity with the exposure doses in the PBMCs (r, 0.249-0.508), while the opposite was the case for the other components of the peripheral blood (r, 0.806-0.934). The correlation coefficients were higher (0.842-0.962) among the whole blood, plasma and RBCs than between PBMCs and other components, such as Se (0.376-0.529), Cd (0.495-0.604) and, especially, Mo (0.160-0.257). In conclusion, PBMCs might provide information about endogenous factors, and whole blood could more accurately reflect the effects of exogenous factors compared to other blood components.

[Effects of lead exposure on 18 elements in blood and excretions in rats].

OBJECTIVE: To investigate the effects of lead exposure on lead and other metal elements contents in rats. METHODS: SD rats were randomly divided into control group and several experiment groups of different doses. The rats were exposed to lead acetate through intragastric administration every other day for 5 times. The whole blood, urine and feces of all the rats were collected. The concentrations of lead and 18 metal elements in these samples were determined by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atom emission spectrometry (ICP-AES). RESULTS: No significant difference among the groups was found for body weight and organ-body ratios of the rats after lead exposure (P>0.05). With the increase of exposure dose, lead content in blood, total lead in urine and feces tended to increase, while the total lead in urine no longer increased in the high dose group. Significant differences among the groups (P<0.05) were observed for the sodium, magnesium, potassium, strontium, antimony, thallium and bismuth contents in the whole blood, the potassium, iron and antimony contents in the urine, and the calcium, iron, zinc, copper, thallium, bismuth and rare earth elements contents in the feces. CONCLUSION: The effect of lead on the metabolism of divalent metal ions, namely calcium, magnesium, iron, zinc, copper and strontium ion, may be due to the competition of lead with the ions for common delivery carrier. Lead exposure induces the excretion of light rare earth elements and toxic elements (thallium and bismuth), and changes the antimony, sodium and potassium contents in rats. But there is no effect of lead on molybdenum and cadmium in rats.

Variations in lead isotopic abundances in Sprague-Dawley rat tissues: possible reason of formation.

It has been reported in previous research that the lead isotopic composition of blood, urine and feces samples statistically differed from the given lead sources in Sprague-Dawley (SD) rats. However, the reason for this phenomenon is still unclear. An animal experiment was performed to investigate the lead isotope fractionation in diverse biological samples (i.e., lungs, liver, kidneys, bone) and to explore the possible reasons. SD rats were intratracheally instilled with lead acetate at the concentrations of 0, 0.02, 0.2, and 2 mg/kg body weight. Biological samples were collected for lead isotope analysis using an inductively coupled plasma mass spectrometry (ICP-MS). Significant differences are observed in lead isotope abundances among the diverse biological samples. The lead isotope abundances ((206)Pb, (207)Pb and (208)Pb) in diverse biological samples show different degrees and directions of departure from the given lead source. The results suggest that differences in enrichment or depletion capacity for each lead isotope in the various tissues might lead to the variation in lead isotopic abundances in tissues. Moreover, a nonlinear relationship between the blood lead level and the lead isotope abundances in liver and bone is observed. When the whole-blood level is higher than 50 ng/mL, the lead isotopic compositions of biological samples tend to be the same. Thus, the data support the speculation of a fractionation functional threshold.

[Investigation of the enrichment and separation of lead and lead isotopes in simulated blood matrix].

The enrichment and separation method was used in the present paper to overcome the influence of matrix effect on the determination of lead concentration and isotope ratios. The patented method was used to enrich and separate the lead in simulated blood matrix; the lead concentrations and isotope ratios were determined by ICP-MS before and after enrichment and separation. The recovery rate of Pb is more than 99% through this method while the removal rate of major impurity ions such as Na, K is about 80%. The concentrations of each lead isotope decrease with the matrix concentration increasing (p < 0.001), and lead isotope ratios show no significant differences in the matrix of different concentrations. When the matrix concentration is more than 62.5 microg x mL(-1), the strength will decrease with the determination times increasing. It was concluded that the characteristics of this method are of high recovery rate (> 99%), fast, simple and convenient, and it can raise the accuracy and precision of the concentration determination of lead isotopes and has no significant influence on the accuracy of lead isotope ratios determination.

Biological fractionation of lead isotopes in Sprague-Dawley rats lead poisoned via the respiratory tract.

OBJECTIVES: It was considered that lead isotope ratios did not change during physical, chemical, or biological processes. Thus, lead isotope ratios have been used as fingerprints to identify possible lead sources. However, recent evidence has shown that the lead isotope ratios among different biological samples in human are not always identical from its lead origins in vitro. An animal experiment was conducted to explore the biological fractionation of lead isotopes in biological systems. METHODS: 24 male Sprague-Dawley (SD) rats were divided into groups that received acute lead exposure (0, 0.02, 0.2, or 2 mg/kg body weight of lead acetate) via the respiratory route every day for 5 days. Biological samples (i.e., blood, urine, and feces) were collected for comparison with the lead acetate (test substance) and the low-lead animal feed (diet) administered to the rats. The lead isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: There are significant differences (p<0.05) in lead isotope ratios between blood, urine, and feces. Moreover, a nonlinear relationship between the blood lead concentration and the blood lead isotope ratios was observed. There is also a threshold effect to the fractionation function. Only the blood isotope ratio of (204)Pb/(206)Pb matches the test substance well. As for feces, when (204)Pb/(206)Pb ratio is considered, there is no significant difference between feces-test substance pairs in medium and high dose group. CONCLUSIONS: The biological fractionation of lead isotopes in SD rats was observed. Moreover, there might be a threshold for the biological fractionation of lead isotopes which is depending on whole blood lead level. It is considered to be more reliable that we compared the isotope ratios of potential lead hazards with both blood and feces lead fingerprints especially for (204)Pb/(206)Pb ratio under high-dose exposure.