Oxidative stress indices in ASD children in Sub-Sahara Africa

Ishiaq Olayinka Omotosho,Ikeoluwa Abiola Lagunju,Adekunbi Olufunke Akinade,Momoh A Yakubu

doi:10.1186/s11689-021-09379-w

Ishiaq Olayinka Omotosho, Ikeoluwa Abiola Lagunju + Show 2 more

Open Access

https://doi.org/10.1186/s11689-021-09379-w

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Abstract

BackgroundThe pathogenesis of autism spectrum disorder (ASD) remains a medical challenge even in the developed world. Although genetics and epigenetic factors have been variously indicted as major causes of the disorder, development of oxidative stress especially in the formative years of children has equally gained prominence as an etiological basis of the disorder. Oxidative stress is characterized by the production of excessive amounts of free radicals, decreased levels of antioxidants with the attendant imbalance in oxidant/antioxidant ratio. This study was designed to determine the levels of essential metals [magnesium (Mg), zinc (Zn), and copper (Cu)] and toxic metal, lead (Pb), and generation of oxidative stress by their abnormal interaction.MethodTwenty-five children clinically diagnosed for ASD according to DSM-IV-TR and 25 neuro-typical (NT) children (controls), (aged 5.96 ± 1.40 years and 6.18 ± 2.59 years respectively) were recruited for this study. Essential and toxic metals were analyzed using induction-coupled plasma-mass spectrometry (ICP-MS); oxidative stress markers [malondialdehyde (MDA), total plasma peroxidase (TPP), and total antioxidant capacity (TAC)] were determined using appropriate biochemical methods. Oxidative stress index (OSI) was calculated.ResultsThe levels of TPP and TAC were significantly reduced while MDA was higher in ASD compared to NT. Although OSI was higher in ASD, the difference was not significant. Pb (lead) concentration was significantly increased while Mg, Zn, and Cu levels were reduced significantly in ASD compared to NT. A significant negative correlation between Mg and OSI (r = − 0.438; p = 0.029) was observed in NT.ConclusionReduction in Zn and Mg levels with a concurrent increase in Pb in children with ASD in this study may be the basis of inadequate TAC manifesting as increased MDA and reduced TPP levels. The attendant imbalance in oxidant/antioxidant ratio may result in abnormality in neuronal transduction leading to the abnormal cognitive and speech functions characteristic of ASD.

Highlights

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is becoming increasingly prevalent
The levels of total plasma peroxidase (TPP) and total antioxidant capacity (TAC) were significantly reduced while MDA was higher in autism spectrum disorder (ASD) compared to NT
Oxidative stress index (OSI) was higher in ASD, the difference was not significant

Summary

Introduction

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is becoming increasingly prevalent. That the pathophysiology of ASD involve oxidative stress resulting from exposure to heavy metals as environmental pro-oxidants has been reported [6]; there are limited or no information on this aspect of the disorder in sub-Sahara Africa. This write-up, examines the impact of exposure to some toxic and essential metals on levels of oxidative stress markers/indices in the development of ASD using black African children as a model. Genetics and epigenetic factors have been variously indicted as major causes of the disorder, development of oxidative stress especially in the formative years of children has gained prominence as an etiological basis of the disorder. This study was designed to determine the levels of essential metals [magnesium (Mg), zinc (Zn), and copper (Cu)] and toxic metal, lead (Pb), and generation of oxidative stress by their abnormal interaction

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