Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders, with a population prevalence of approximately 0.5-1.5%. ASDs are more common in males than in females, with a gender ratio of approximately 4:1. Autism comprises a heterogeneous group of neuro-developmental disorders known as autism spectrum disorders (ASDs) characterized by deficits in verbal and non-verbal communication, social interaction, restricted interests, and stereotyped behavior.
Glutamate and GABA are the main excitatory and inhibitory neurotransmitters in the human brain. There is an imbalance between excitation and inhibition in local circuits that involved in sensory, mnemonic, social and emotional processes in ASDs. ASDs share overlapping symptoms, indicating common deficits in some neuro-developmental pathways. There are two facts of GABA dysfunctioning (Reduction of GABA & alteration of GABAergic circuit). Besides, abnormally enhanced glutamatergic signaling may contribute to epilepsy in the autistic population.
Studies from animal models of ASDs indicate that a dysfunction in GABAergic signaling within particular neurons cause most of the clinical symptoms found in autistic patients. Studies showed that the GABA concentration in the frontal lobe and auditory cortex of persons with ASD and unaffected siblings of persons with ASD is lower compared to normal population.
People deficient in GABA are prone to neurological issues of over-excitability: seizures, agitation, irritability, and anxiety. All of these issues are common in ASD patients. Symptoms of acute agitation, anxiety, and self-harm in individuals without ASD are often treated with anxiolytic drugs like benzodiazepines, which increase the concentration of GABA in the synaptic cleft of neurons. The subsequent inhibition of neurotransmission transiently calms the patient. This means that supplementation with GABA could provide a similar effect, potentially addressing the same symptoms of excitation in ASD without the risks inherent to benzodiazepines.
In conclusion, GABA can be considered to address multiple symptoms of autism spectrum disorder. As GABA may help with ASDs condition but it may not be a main treatment for autism as some patients with autism may have neuronal defects that prevent them from effectively using additional GABA.
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