Autism Spectrum Disorder

Context:

Autism spectrum disorder (ASD) is the term for a group of neurodevelopmental disorders. Researchers are yet to fully understand the causes of ASD.

Relevance:

GS II: Health

Dimensions of the Article:

1. Autism spectrum disorder
2. Exploring the Connection between Gut Microbiome and Autism Spectrum Disorder (ASD)
3. Ongoing Research on the Gut Microbiome and Autism Spectrum Disorder (ASD)

Autism spectrum disorder

Autism Spectrum Disorder (ASD) refers to a group of neurodevelopmental disorders that impact social interaction, communication skills, and behavior.

• Researchers have yet to fully understand the causes of ASD, but a disorder in the gut-brain axis may have a prominent role.

Prevalence and Characteristics of ASD

• According to the WHO, ASD affects one in 100 children, and it can have a significant impact on cognitive abilities and quality of life.
• Children with ASD may exhibit impaired social interactions, lack of verbal and nonverbal communication skills, and restricted and repetitive behaviors.

Gastrointestinal Problems Associated with ASD

• Some children with ASD experience gastrointestinal problems, such as constipation, diarrhea, flatulence, and bloating, among others.
• Limited research findings and anecdotal evidence suggest that there is a link between gastrointestinal problems and ASD, but this area remains relatively under-researched.

Pathophysiology and Current Treatment for ASD

• Although several theories have been proposed to explain the aetiology of ASD, the pathophysiology of the disorder remains largely unknown.
• There are currently no known cures or therapeutic interventions available to treat or reverse ASD, highlighting the need for continued research in this area.

Note:

• Aetiology is the study of factors that cause a condition or disease.
• Pathophysiology is the study of a condition’s impact on biological processes.

Exploring the Connection between Gut Microbiome and Autism Spectrum Disorder (ASD)

The Impact of Gut Microbiome on Human Health

• Advances in gene-sequencing technologies and bioinformatic analysis have helped researchers to explore the connections between human health, diseases, and microbiomes.
• The gut microbiome has been found to have a significant impact on immune modulation and metabolic activities in the human body.

Potential Connections between Gut Microbiome and ASD Symptoms

• Investigating the dynamic cross-talk between the gut microbiome and the host environment has revealed potential connections to ASD symptoms.
• Aberrant antigen trafficking through an impaired intestinal barrier could allow antigens to pass through the barrier surrounding the brain, triggering a chain of events that worsen ASD symptoms.

The Role of Gut Microbiome in the Pathophysiology of ASD

• Some scientists have disputed the significance of the gut microbiome in the pathophysiology of ASD, arguing that it cannot cause ASD.
• However, research has shown that abnormalities in the gut microbiome can challenge a person with toxic metabolites, hindering the synthesis of neurotransmitters involved in cognition, behavior, mood, and sleep.
• Fixing the gut microbiome in ASD can reduce the toxic burden and/or help complete necessary neurotransmitter synthesis pathways, potentially improving symptoms.

Ongoing Research on the Gut Microbiome and Autism Spectrum Disorder (ASD)

Dysbiosis in the Gut Microbiome of Children with ASD

• In their research, the authors have explored the gut microbiome in children with and without ASD and have reported several interesting microbial biomarkers in children with ASD.
• Dysbiosis, an imbalance in the gut microbiome, was observed in children with ASD. They had a higher abundance of lactobacillaceae, bifidobacteriaceae, and veillonellaceae bacteria, and the fraction of bacteria of the phylum firmicutes was found to be significantly higher in their guts.

Short-Chain Fatty Acids and the Gut-Brain Axis

• The authors found an underrepresentation of certain microbes that produce short-chain fatty acids (SCFA) in children with ASD, such as faecalibacterium and roseburia.
• This supports the hypothesis that a lower level of SCFAs in ASD could lead to an imbalance in brain function and behavior.
• Some proposals suggest introducing these strains of bacteria as a probiotic for children with ASD to help alleviate common gastrointestinal problems and positively influence cognitive and behavioral functions.

Emerging Areas of Study and Future Consensus

• Since these are emerging areas of study, there are pockets of agreement as well as disagreement in the scientific community.
• The consensus on the role of the gut microbiome in ASD lies in the future as further research is conducted.

-Source: The Hindu