Scientists around the world are trying hard to understand brain conditions like autism, schizophrenia, and Alzheimer’s disease. These are not simple problems.
They affect how people think, feel, behave, and interact with others. While some causes like gene changes and protein issues have been found, many things about the brain are still a mystery.
One protein that hasn’t been well studied is called IDO2. This protein plays a role in breaking down tryptophan, which is a part of the food we eat. Tryptophan is an amino acid found in foods like eggs, cheese, and meat.
When the body breaks it down, it creates other substances through a process called the tryptophan–kynurenine pathway. Some of the substances made during this process have been connected to mental health issues. But scientists didn’t really know what IDO2 itself was doing.
To explore this, researchers in Japan led by Associate Professor Yasuko Yamamoto created a group of mice that didn’t have the IDO2 gene. These mice were known as “knock-out” mice because the gene was completely removed. The researchers then watched how these mice acted, compared to normal mice.
The results were surprising. The mice without IDO2 behaved in odd ways. They didn’t like new situations and repeated their grooming actions many times, which was unusual. They also didn’t show much interest in exploring and had trouble learning from other mice. These signs looked very similar to behaviors often seen in people with autism.
To understand what was happening in the brain, the researchers studied brain chemicals. They found that the mice with no IDO2 had changes in how tryptophan was broken down. This led to differences in a brain chemical called dopamine.
Dopamine helps control mood, learning, and motivation. In certain brain areas such as the striatum and amygdala, dopamine levels were not normal in the mice missing IDO2. This might be one reason they acted differently.
Another thing the scientists noticed involved BDNF, a substance that helps brain cells grow and connect. In the IDO2-lacking mice, there were fewer strong brain connections and more weak ones. This could explain some of their learning and behavior problems.
The researchers also looked at microglia, which are tiny cells that protect the brain. Usually, these cells are calm and keep an eye on things. But in the IDO2-deficient mice, the microglia were more active than normal, which might have caused extra problems in the brain.
The best part of the study was that when the scientists put the IDO2 gene back into the knock-out mice, their behavior improved. They started acting more like normal mice. This shows that IDO2 might be very important for healthy brain function and behavior.
The researchers also looked at brain samples from over 300 people with autism. In one case, a teenage girl had a mutation in the IDO2 gene. This doesn’t prove IDO2 causes autism, but it adds more evidence that the protein could be involved.
This study is important because it gives scientists a new direction to explore. If IDO2 really plays a key role in the brain, future treatments could be developed to help fix chemical imbalances that cause learning, emotional, or social problems.
While more research is needed, this discovery gives hope to families and scientists who are looking for better ways to support people with autism and other brain conditions.
If you care about autism, please read studies about food additives and ADHD, and natural fixes for ADHD.
For more health information, please see recent studies about nutrition’s role in managing ADHD, and this type of food may contribute to autism.
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