Oxidative stress indices in ASD children in Sub-Sahara Africa

Abstract

Background The 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. Method Twenty-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. Results The 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. Conclusion Reduction 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.

Measuring Some Oxidative Stress Biomarkers in Autistic Syrian Children and Their Siblings: A Case-Control Study

“…However, higher MDA and AOPP levels were observed in children with ASD in comparison with non-related control ( P = .0001), these results were similar to the results of Meguid et al, 18 Omotosho et al, 19 and Altun et al 20 studies, which found significantly higher levels of MDA in children with ASD when compared with control with no ASD ( P < .0001). Furthermore, our findings corresponded with the results of Ahmad et al study, 21 which found higher levels of AOPP (+120.6%) in children with autism spectrum disorder when compared with the control ( P ⩽ .05), denoting the relation between oxidative stress and ASD.…”

Mitochondrial Oxidative Stress—A Causative Factor and Therapeutic Target in Many Diseases

“…In the case of autism mitochondrial abnormality, augmented oxidative stress and decreased antioxidant capacity have been reported in autistic persons, all of which may be responsible for neuroinflammation and autism pathology [76,77]. Recent analysis of blood samples from children with autism spectrum disorders revealed reduced total plasma peroxidase and total antioxidant capacity, resulting in an imbalance in the oxidant/antioxidant ratio and abnormalities in neuronal transduction [78]. Zawadzka et al [79] showed that impaired brain development is a consequence of inflammatory processes inducing oxidative stress and mitochondrial damage, which in turn exacerbate oxidative stress, triggering further cellular damage.…”

Does Lead Have a Connection to Autism? A Systematic Review and Meta-Analysis

“…The characteristics of the studies included in the meta-analysis are shown in Table 1 . The meta-analysis of Pb levels in hair included 17 studies [ 19 , 32 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 ], 13 studies in whole blood [ 20 , 31 , 34 , 44 , 58 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 ], and 8 studies in urine [ 24 , 34 , 36 , 58 , 70 , 71 , 72 , 73 , 74 ].…”