A novel study on amyloid β peptide 40, 42 and 40/42 ratio in Saudi autistics

Concentrations of human Aβ (1-42), Aβ (1-40), and Aβ (40/42) in the plasma of 52 autistic children (aged 3-16 years) and 36 age-matched control subjects were determined by using the ELISA technique and were compared.Compared to control subjects, autistic children exhibited significantly lower concentrations of both Aβ (1-40) and Aβ (1-42) and lower Aβ (40/42) concentration ratio. Receiver operating characteristics curve (ROC) analysis showed that these measurements of Aβ peptides showed high specificity and sensitivity in distinguishing autistic children from control subjects.Lower concentrations of Aβ (1-42) and Aβ (1-40) were attributed to loss of Aβ equilibrium between the brain and blood, an imbalance that may lead to failure to draw Aβ from the brain and/or impairment of β- and γ- secretase's concentration or kinetics as enzymes involving in Aβ production.Autism and other related autism spectrum disorders (ASDs) are behavioral syndromes that include various degrees of verbal, nonverbal, and social impairment, as well as restricted or stereotyped interests and activities. The disorders are characterized by early onset (before 36 months of age) [1,2] and by long-lasting social or cognitive handicaps. With an overall prevalence of approximately 0.6% [3], ASDs are an important public health problem worldwide. Although international consensus considers these syndromes to be phenotypic expressions of impairments affecting the development of the central nervous system (CNS), numerous questions concerning their etiopathology are still unanswered.Children with autism generally find it difficult to ignore irrelevant information and are easily distracted by other stimuli. Therefore, we can assume that these children may have a selective attention deficit. In humans, prenatal stress is linked to an increased vulnerability to various psychosocial problems of childhood and adulthood. In children, stress is associated with cognitive, behavioral, physical, and emotional proble