Evaluation of whole blood zinc and copper levels in children with autism spectrum disorder

Abstract

Zinc (Zn) and copper (Cu) are important trace elements for cognitive development and normal neurological functioning. Autism spectrum disorder (ASD) is a common neurological disorder, which has previously been associated with the levels of some trace elements in the blood. However, clinical data regarding the potential implication of Zn and Cu in patients with ASD are still insufficient. Therefore, the aim of the present study was to investigate the whole blood levels of Zn and Cu in a cohort of 28 children with ASD and 28 age- and gender-matched healthy controls. Whole blood Zn and Cu levels were assessed using inductively-coupled plasma-sector field mass spectrometry. Both in the control and in the ASD group, the values of whole blood Cu and Zn were characterized by a Gaussian distribution. The results indicate that the ASD children were characterized by ~10 % (p = 0.005) and ~12 % (p = 0.015) lower levels of whole blood Zn and Zn/Cu ratio, respectively, in comparison to controls. No significant difference in whole blood Cu was observed. However, Cu/Zn ratio was ~15 % (p = 0.008) higher in ASD children than that in the control ones. The results of the present study may be indicative of Zn deficiency in ASD children. Taking into account Zn-mediated up-regulation of metallothionein (MT) gene expression, these findings suggest a possible alteration in the functioning of the neuroprotective MT system. However, further investigations are required to test this hypothesis.

The Correlation between Early Stages of Life Exposed to Chinese Famine and Cognitive Decline in Adulthood: Nutrition of Adulthood Plays an Important Role in the Link?

“…Numerous people-based study suggested iron, zinc, iodine, folates and B vitamins might improve cognitive performance ( Nyaradi et al, 2015 ; Shah-Kulkarni et al, 2016 ; Portbury et al, 2017 ). In contrary, zinc and copper were believed to result in β-amyloid peptides aggregation which is one of the major pathological markers in the brain of AD patients ( ElAli et al, 2013 ; Crăciun et al, 2016 ). The reason of this inconsistent might be inappropriate analysis methods, different selection of sample and matching controls ( Modgil et al, 2014 ).…”

Immune dysfunction and neuroinflammation in autism spectrum disorder

“…A recent study suggests that increased levels of BPb in some children with ASD may trigger the production of serum anti-ribosomal P antibodies (Mostafa et al 2016b). It has been reported that ASD children often have a lower zinc (Zn)-to-copper (Cu) ratio in blood compared to healthy controls (Faber et al 2009, Li et al 2014, Crăciun et al 2016) and children with other neurological disorders (Macedoni-Lukšič et al 2015). It has been suggested that metallothionein (MT) dysfunction may occur as a cause of Hg accumulation in children with ASD, and the same dysfunction may also lead to Zn deficiency (Bjørklund 2013).…”

Physiological Roles of Metallothioneins in Central Nervous System Diseases

“…There is no detailed report on the action mechanisms related to psychological disorders and PSD95-3MT; therefore functional analysis in future studies might also be beneficial. In addition, there are some reports on psychological stress-induced zinc accumulation and MT upregulation in the liver, 93) and MT gene expression mediated by zinc was upregulated in children with autism spectrum disorder. 94) Furthermore, our laboratory reported that reduction of MT-3 might be induced by abnormal behaviors such as psychiatric disorders using MT-3 KO mice.…”