Neurotransmitters are brain chemicals that support and govern development. Many neurotransmitters are needed to create the environment needed for optimal language, social and cognitive development.
Serotonin is a key brain chemical that is been identified in the physiological abnormalities in ASD. Serotonin is made from tryptophan with the help of co-factors including vitamin C, folate, iron, calcium, magnesium and B6. Tryptophan is an amino acid, which is a building block that makes up protein protein. Children with developmental disorders often show amino acid deficiency including tryptophan. They also have an inability to effectively convert B6 to its active form P5P. Digestive problems in autism reduce the levels of necessary components needed in the production of brain chemicals, like serotonin and eighty to ninety percent of serotonin resides in the gut cells where it helps to regulate intestinal movements (see constipation and picky eating for more information). Abnormal levels of serotonin have been found in autism and serotonin receptors in different areas of the brain may explain some autistic behaviours and delays.
Serotonin is responsible for regulating:
- Sensory Perception
- Noise sensitivity
Dopamine is needed for fundamental brain function. Dopamine receptors have abnormal form in children with developmental delays. The methylation cycle provides the primary fuel for dopamine receptors in the brain. Children with autism and ADHD often have dysregulation in their dopamine system. Low dopamine levels impair attention and focus. High dopamine levels cause the mind to race and increase sensory perception which causes an overload on the brain’s ability to process. Dopamine is produced from the amino acid tyrosine with the help of iron, vitamin C, folate, vitamin B6 and tetrahydrobiopterin (which requires dihydrafolate from green leafy vegetables). Mothers who have a different form of the gene COMT are seven times more likely to have a child diagnosed with autism. COMT converts dopamine to norepinephrine and mutations in the COMT enzyme result in dopamine creating oxidative stress in the brain. The COMT enzyme is extremely sensitive to lead and benefits from reducing body burden of lead and other harmful toxins. COMT V158M decreases the activity of the enzyme by 300 percent and children with this SNP benefit from supplementation with magnesium, curcumin and inositol. In practice, we see a correlation between COMT SNPs and PANDAS and tic disorders like Tourette syndrome.
Dopamine is responsible for regulating:
- Sensitivity and processing of information
- Perception of change
- Relaying information
- Fundamental brain function – cognition
- Emotional Responses
- Attention and Focus
GABA and Glutamate
GABA is a calming neurotransmitter that impacts up to 40% of brain synapses. It is created from glutamate (via the Kreb’s cycle from alpha-keto-glutarate) with the help of B6 in its activated form P5P, zinc, n-acetyl-cysteine and taurine. Research into the autistic brain has identified an imbalance in glutamate to GABA receptors. Deficient levels of GABA or problems with GABA receptors are thought to play a role in the excitatory elements of autism, ADHD and seizures. Identifying and addressing problems with neurotransmitter systems is a key component to biomedical treatment of autism and other developmental delays.
There are a lot of brain chemicals or neurotransmitters that are needed to regulate brain function. Glutamate is the most abundant neurotransmitter in the brain. It is essential for the development and function of the brain. It is also strictly regulate because in high amounts, it can change the way to brain functions and even cause damage. Glutamate is stimulated by the glia (the immune cells in the brain) in response to threat like chemicals, metals or microbes. The glia work to control the threat and repair damage to the brain. The brain requires adequate levels of glutathione to manage glutamate.
Glutathione is the master antioxidant in the body and brain. It helps to protect cells from damage and is needed to “mop” up excess glutamate. Glutathione is the rate limiting step in development. Developmental speed depends on glutathione produced by the methylation cycle. Glutathione helps to detoxify many harmful toxicants including metals and chemicals. Depletion of glutathione, results in higher levels of glutamate in the brain triggering a cascade of events that cause disruption of typical brain function and damage. This cascade is a proposed central mechanism of autism described by renowned neurologist, Dr. Russell Blaylock, MD, who coined the term immunoexcitotoxicity.