An additive found in hundreds of foods may help further research on debilitating brain disorders, a study suggests.
Neuroscientists and engineers have long built three-dimensional brain-like structures called organoids from human stem cells for scientific research.
These are meant to mimic the composition and function of a real brain, allowing scientists to study brain disorders like epilepsy and autism, as well as rare conditions.
The stem calls form structures that resemble parts of an early-life developing brain. However, organoids naturally stick together and fuse during the processing, making them quickly unusable, and it is difficult to grow multiple batches for large-scale testing.
This poses a challenge as scientists generally need thousands of organoids to properly study the brain.
Researchers at Stanford University sought to find materials that could keep brain organoids separate during growth, allowing them to be used for longer and produced at a faster rate.
In a new study, the team tested 23 materials on the organoids and found one solution that worked to keep the organoids separate: xanthan gum, which is used to thicken or stabilize foods.
The researchers said the findings would give them significantly more organoids to use for crucial testing on chronic conditions like epilepsy and autism and the safety of potent medications on vulnerable groups like pregnant women and children.
Stanford University researchers discovered the food additive xanthan gum may prevent brain models called organoids from separating, helping them study neurological disorders (stock image)
Xanthan gum is found in hundreds of foods from salad dressings to baked foods to ice cream, as well as personal care products like toothpaste, lotion and shampoo.
In foods, xanthan gum has been linked to digestive side effects like increased bowel movements, diarrhea and gas, and emerging research also suggests the additive could be linked to colorectal cancer, as it may alter gut bacteria and induce inflammation, which damages cell DNA and encourages the formation of cancer cells.
But in the lab, Stanford researchers believe it will help them create thousands more organoids to study chronic brain conditions.
And it comes amid a dire time, as the team said they previously had so few that it severely limited their research.
Sergiu Pasca, lead study author and professor of psychiatry at Stanford’s School of Medicine, said: ‘We can easily make 10,000 of them now.
‘This, as with all of our methods, is open and feely accessible. There are already numerous labs that have implemented this technique.’
The team is planning to use the organoids to research conditions that occur in the brain during early life like autism and Timothy syndrome, a rare disorder caused by mutations in the CACNA1C gene.
Timothy syndrome affects fewer than 100 people around the world and leads to heart conditions like long QT syndrome and tachycardia (when the heart beats too quickly), developmental delays, infections and seizures.
The team’s ability to focus on autism may also provide clues into the rise of the condition, which affects one in 31 children in the US.
The new study, published in June in the journal Nature Biomedical Engineering, tested the effects of 23 different materials on keeping organoids separated.
Sarah Heilshorn, study author and Rickey/Nielsen Professor in the School of Engineering at Stanford, said: ‘We selected materials that were already considered biocompatible and that would be relatively economical and simple to use, so that our methods could be adopted easily by other scientists.’
The researchers grew organoids in a nutrient-rich liquid for six days and then added one of the test materials. They then measured the number of remaining organoids 25 days later.
They found that even in small amounts, xanthan gum was the only material that kept the organoids from fusing together.
Xanthan gum is an emulsifier, which is used in foods like salad dressing to help thicken and stabilize them (stock image)
To demonstrate how the technique could be used by other scientists, co-lead study author Genta Narazaki grew 2,400 organoids in batches and added one of 298 FDA-approved drugs to each patch to see if any of them caused growth defects.
They found several of the drugs stunted growth of the organoids, suggesting they could be harmful to brain development.
The findings mean having a greater batch of organoids would allow scientists to thoroughly research the effects of medications on fetal brains, which would help guide safety recommendations for medications pregnant women should and should not take.
Pasca said: ‘One single experimenter produced thousands of cortical organoids on their own and tested almost 300 drugs.’
The team plans to use the method to make more organoids and use them to evaluate the causes and progression of neuropsychiatric disorders like autism, epilepsy and schizophrenia.
Pasca said: ‘Addressing those diseases is really important, but unless you scale up, there’s no way to make a dent.
‘That’s the goal right now.’