(1) Arkansas Children’s Hospital Research Institute, Little Rock, AR, USA
(2) Rossignol Medical Center, Irvine, CA, USA
* Corresponding author Email: REFrye@uams.edu
Recent studies have suggested that mitochondrial dysfunction is relatively common in many children with autism spectrum disorder (ASD) and appears to be the most prevalent metabolic disorder associated with ASD. However, the exact prevalence of mitochondrial disease in ASD is not clear as the classic criteria for diagnosing mitochondrial disease in ASD appear to underestimate the true prevalence. Indeed, the prevalence of biomarkers of mitochondrial dysfunction and abnormal electron transport chain function appears to be high in ASD. In addition, recent studies have uncovered novel forms of mitochondrial dysfunction in ASD that may not be readily recognized by classic diagnostic criteria. This critical review provides a brief overview of mitochondrial function and its influence on other cellular systems in the context of ASD. The mitochondria’s role in producing energy is complex and linked to other metabolic systems. Mitochondrial energy production is a result of the tricarboxylic acid cycle, fatty-acid oxidation and the electron transport chain working in concert. The unique architecture of the mitochondria facilitates the function of these systems. The function and architecture of the mitochondria for producing energy with a special reference to the source of biomarkers of mitochondrial dysfunction is reviewed. Non-energy functions of the mitochondria including calcium buffering, heat production and apoptosis are outlined. Interactions with other systems, including the porphyrin pathway, urea cycle and glutathione metabolism, are also outlined, followed by a discussion of mitochondrial control and regulation. Finally, the recommended algorithm for the diagnosis of mitochondrial disorders in children with ASD is discussed.
The mitochondrial is critically important in understanding the physiological abnormalities associated with ASD. By providing details regarding mitochondrial function, this critical review aims to provide a better understanding of the importance of mitochondria as it is related to ASD.