KU Leuven: SCIENTISTS ARGUE FOR FURTHER RESEARCH AND MEDICAL ADVICE ON USE
A study led by researchers from Leuven and Spain provides new insights into the potential benefits of using green tea supplements in Down syndrome. One of the main components influences the facial development of children with Down syndrome in the first years of life, as a result of which the characteristic facial features associated with the syndrome are less reflected. Additional experimental research in mice confirms this effect, although it also shows risks when using a high dose. Further research is needed to fully understand the effects of these supplements and therefore use without medical advice is not recommended.
Down syndrome is a birth defect caused by the presence of an extra, third copy of chromosome 21. The genes on this chromosome are overexpressed, leading to physical and mental disabilities. One of these genes, DYRK1A, contributes to the disruption of brain and bone development in Down syndrome. The substance EGCG ( epigallocatechin-3-gallate ), present in green tea extracts, suppresses the activity of DYRK1A. An earlier study in Spain already showed that the substance has a potential beneficial effect on the cognitive skills of young adults with Down syndrome.
New research analyzed the effects of green tea supplements on the facial development of children with Down syndrome. In the experimental part, carried out at KU Leuven, the supplements were tested on mice in different doses. In addition, research institutions in Spain (CRG, EMBL and the University of Barcelona) conducted an observational study in children with and without Down syndrome.
Treatment of the mice was started while the animals were pregnant. Green tea extracts were administered to the pups in the womb through the mother’s drinking water, either in a low or high dose. “A low dose of the extracts had a positive effect on the mice that model Down syndrome,” says Professor Greetje Vande Velde (Department of Imaging and Pathology), one of the lead authors. “Sixty percent had a face shape similar to the control group without the Down syndrome model.”
The high dose, on the other hand, produced more mixed results. In some cases, the facial development in the mice was even disturbed, resulting in further malformation. We found this not only in the model for Down syndrome, but also in other mice. ”
Age-related effects
The observational study enrolled 287 children between the ages of zero and eighteen, including children with Down syndrome who took (13) and not (63) green tea supplements. The children who were given supplements did so on their own initiative and did not follow a predetermined schedule.
The observational study shows that green tea extracts mainly influence facial development in the first years of life.
All participants were photographed from different angles to construct a detailed 3D model of their faces. The researchers used 21 checkpoints and the distances between them to compare the faces.
In the youngest group between the ages of zero and three, they found that these ratios differed 57 percent between the children with Down syndrome and the control group without. In peers with Down syndrome who took green tea supplements, the difference from the control group was much smaller, but 25 percent. The characteristic facial features associated with the syndrome were less evident. So the children with or without Down syndrome looked more alike.
This effect was less clear in the teens and young adults (thirteen to eighteen years old). Even after taking the supplements, the difference was more than fifty percent. So it seems that green tea extracts affect facial development especially in the first years of life, when the face and skull are in full growth.
Need for additional research
“We must interpret these findings, and the potential benefits we have identified for children with Down syndrome, with caution. These are preliminary results, based on an observational study ”, Greetje Vande Velde emphasizes. “Much research is still needed to estimate the effects and correct dosage of supplements containing EGCG. The influence on other organ systems must also be taken into account, now we have only examined the facial development. This requires more basic research in the lab first and then large clinical studies with more participants and controlled administration of these supplements. ”
“Our results indicate that the dosage plays an important role,” says Professor Vande Velde. “Green tea supplements with EGCG are available over the counter and many people use them to promote their general health. It is very important to follow the European instructions for use and to always seek medical advice before use. With our research we show that a low dose has potentially beneficial effects on facial development, but at the same time that a high dose in mice produces unpredictable results. More research in humans is needed to determine the optimal dosage for each age group and to develop the therapeutic potential. ”