Manganese and selenium concentrations in cerebrospinal fluid of seriously ill children

Blood-cerebrospinal fluid barrier permeability of metals/metalloids and its determinants in pediatric patients

Concerns regarding adverse effects of metal/metalloids exposure on brain development and neurological disorders among children are increasing. However, the transport patterns of metals/metalloids across the blood-cerebrospinal fluid barrier (BCSFB) need to be clarified in children. A total of 99 Chinese pediatric patients were enrolled from February 2020 to August 2021, with a median age of 6.76 months. We detected 16 metal/metalloid levels in matched serum and cerebrospinal fluid (CSF) samples using inductively coupled plasma mass spectrometry. The BCSFB permeability of metals/metalloids were estimated and the potential effects of biomedical parameters were explored. Most metals/metalloids were detectable among > 80.0% of CSF samples. Significant correlations were observed between strontium (Sr, r = 0.46), molybdenum (Mo, r = 0.50), and cadmium (Cd, r = 0.24) concentrations in serum and CSF (P < 0.05). Ratios of metal/metalloid levels in CSF to serum (Rmetal) ranged from 0.02 to 0.74, and hazardous metals/metalloids including arsenic (As), Cd, lead (Pb), thallium (Tl), and manganese (Mn) showed high transfer efficiencies across the BCSFB (Rmetals > 0.5). With the adjustment of age and sex, albumin, β2-microglobulin, and total protein levels in CSF were positively associated with copper (Cu) permeability (FDR-adjusted P < 0.05), while glucose in CSF was negatively correlated with calcium (Ca), Cu, Sr, and Mo BCSFB permeability (FDR-adjusted P < 0.05). Q-Alb promoted Cu permeability across the BCSFB (FDR-adjusted P < 0.001), while C-reactive protein levels in serum were positively associated with selenium (Se) permeability (FDR-adjusted P = 0.046). For the first time, our findings provided data for the BCSFB permeability of 16 metals/metalloids in children, and indicated that some biomedical parameters could influence the transformation of metals/metalloids from serum to CSF. Metals/metalloids with strong BCSFB permeability warrant attention for their potential neurotoxicity.

The Use of Trace and Essential Elements in Common Clinical Disorders: Roles in Assessment of Health and Oxidative Stress Status

During the early life, the diet of infants is mainly dominated by milk. Milk is a natural food rich in trace elements focus on essential elements. These elements are very necessary for human metabolism and since they cannot be synthesized by the body, the only source available for the humans to obtain them is by ingestion of natural food. This mini-review aims at updating the knowledge on trace elements, outlining their natural food sources, and their possible implications in common clinical disorders in early and adult life. However, it was found that consumption of food with micronutrients and trace elements may release intracellular compounds and offer oxidative protection or exacerbate oxidative damage to metabolically compromised cells.

Association between peripheral manganese levels and attention-deficit/hyperactivity disorder: a preliminary meta-analysis

Evidence has suggested that dysregulation of the dopaminergic system may play a significant role in the pathogenesis of attention-deficit/hyperactivity disorder (ADHD) in children. Manganese, a neurotoxicant, has been reported to exert its neurotoxicity by affecting the dopaminergic system. However, the association between peripheral manganese levels and ADHD has not been comprehensively reviewed. This study aimed to investigate the association between peripheral manganese levels and ADHD in children. An electronic search was performed on databases including PubMed, ProQuest, ClinicalKey, Cochrane Library, ClinicalTrials.gov, Embase, Web of Science, and ScienceDirect with last search on March 25th, 2018. As per the inclusion criteria, human observational studies investigating peripheral manganese levels in children with ADHD and controls were included. The meta-analysis was performed using a random-effects model, and possible confounders were examined by subgroup analysis. In total, four articles with 175 ADHD children and 999 controls were recruited. The manganese levels were significantly higher in ADHD children than in controls (p=0.033), when studies investigating blood levels and those investigating hair levels were included. However, when only studies investigating blood levels were included, there was no significant difference between ADHD children and controls (p=0.076). Our results support higher peripheral manganese levels in children diagnosed with ADHD than those in controls. Further primary studies are needed to clarify this association.

SLC39A8 deficiency: biochemical correction and major clinical improvement by manganese therapy

PurposeSLC39A8 deficiency is a severe inborn error of metabolism that is caused by impaired function of manganese metabolism in humans. Mutations in SLC39A8 lead to impaired function of the manganese transporter ZIP8 and thus manganese deficiency. Due to the important role of Mn²⁺ as a cofactor for a variety of enzymes, the resulting phenotype is complex and severe. The manganese-dependence of β-1,4-galactosyltransferases leads to secondary hypoglycosylation, making SLC39A8 deficiency both a disorder of trace element metabolism and a congenital disorder of glycosylation. Some hypoglycosylation disorders have previously been treated with galactose administration. The development of an effective treatment of the disorder by high-dose manganese substitution aims at correcting biochemical, and hopefully, clinical abnormalities.MethodsTwo SCL39A8 deficient patients were treated with 15 and 20 mg MnSO₄/kg bodyweight per day. Glycosylation and blood manganese were monitored closely. In addition, magnetic resonance imaging was performed to detect potential toxic effects of manganese.ResultsAll measured enzyme dysfunctions resolved completely and considerable clinical improvement regarding motor abilities, hearing, and other neurological manifestations was observed.ConclusionHigh-dose manganese substitution was effective in two patients with SLC39A8 deficiency. Close therapy monitoring by glycosylation assays and blood manganese measurements is necessary to prevent manganese toxicity.

Manganese and selenium concentrations in cerebrospinal fluid of seriously ill children

BACKGROUND

The homeostasis of essential trace elements such as selenium and manganese may be altered in patients with severe diseases of various etiologies (trauma brain injuries, tumors, leukemias, lymphomas, neurological diseases).

METHODS

Concentration of manganese and selenium were determined in cerebrospinal fluid by electrothermal atomic absorption spectrometry in 50 hospitalized children with various clinical ethiologies including oncological, neurological, and brain related diseases.

RESULTS

The concentrations of manganese in cerebrospinal fluid of children were 0.97±0.67 μg/L. The concentrations of selenium were 13.3±3.5 μg/L. The concentrations were similar as published in adults. The values did not correlated with the age, gender and severity of the disease.

CONCLUSION

We evaluated values of selenium and manganese in cerebrospinal fluid of seriously diseased children.