A Review on Autism Spectrum Disorder: Pathogenesis, Biomarkers, Pharmacological and Non-Pharmacological Interventions

Autistic spectrum disorder (ASD) is a complicated developmental disease characterized by persistent difficulties in social interaction, speech and nonverbal communication, and restricted/ repetitive activities. Our goal is to deliver a step ahead awareness on neurodevelopment in ASD through early behavioral screenings, genetic testing, and detection of various environmental triggers. This would significantly reduce the tally of people with autistic characteristics. As of now, much work is to be done in understanding and treating ASD. Firstly, awareness campaigns must be organized and maintained so that ASD children can be identified and treated feasibly. Secondly, prenatal and prepregnancy environmental risk awareness, including advice against consanguineous marriages, information on optimum mother nutrition, and minimizing pollutants exposure, can be focused. Finally, the extension of genetic screening along with early postnatal monitoring of newborn feeding, nutrition, and eye contact will help in early therapy. People with ASD have strict dietary habits, but they are also more prone to gastrointestinal problems, including diarrhoea, constipation, and sometimes irritable bowel syndrome. Despite significant studies on the symptoms and possible causes of ASD, GI dysfunction is becoming a hot issue of discussion. Dietary strategies can partially help to alleviate both GI and behavioural issues due to the link between gut-microbiota and brain activity. Dietary treatments may be less expensive, easier to administer and have fewer adverse effects than pharmacological interventions. Hence, there is an increasing interest in autistic children's customized diets and supplements. Future studies should look at whether these diets are applicable to diverse people and whether they are practical in various circumstances (areas with fewer resources, lower socioeconomic areas, countries with different dietary restrictions, etc.). The dietary phytochemicals, including curcumin, resveratrol, naringenin, and sulforaphane, have a substantial role as neurotherapeutic agents. These agents can act as an antioxidant, immunomodulator, gut microbiota modulator and Nrf2 activator to provide benefits to ASD patients. Hence an urgent need is to create brain-targeted delivery methods for these dietary phytochemicals and to investigate their therapeutic value in ASD.