In a new study, scientists at the University of Copenhagen
show that a specific type of carbohydrate plays an important role in the
intercellular signaling that controls the growth and development of the nervous
system. In particular, defects in that carbohydrate may result in the
uninhibited cell growth that characterizes the genetic disease
neurofibromatosis and certain types of cancer. The results have just been
published in PNAS.
Scientists from The Faculty of Health and Medical Sciences at the University of Copenhagen
have put a special type of fruit fly under the microscope. The new research
results turn the spotlight on a certain group of carbohydrates—the so-called
glycolipids—and their influence on the cells’ complicated communication system.
In the long term, this model study can shine new light on the disease
neurofibromatosis for the benefit of patients the world over.
“The most important thing about our
discovery right now is that we document a new function for carbohydrates in the
communication between cells. We also show how disturbances in the signaling
pathways cause changes in cellular growth. This is knowledge that cancer
researchers can develop,” says Ole Kjærulff, doctor and associate
professor at the Department of Neuroscience and Pharmacology, who has conducted
the study together with Katja Dahlgaard, and Hans Wandall, associate professor
at the Copenhagen
Center for Glycomics.
Sugar chains control cell growth
Glycolipids are compounds consisting of fats linked to
long chains of sugar molecules. They are located in the cell membrane, where
they serve various functions, such as protecting the cell or making it recognizable
to the immune system.
“In the fruit fly model, if we prevent
the sugar chains from lengthening, we can show that carbohydrate plays an
important role in controlling the growth of normal cells. When the sugar chains
are shortened, the tissue grows dramatically on account of increased cell
division. In particular, it appears that the nervous system’s support cells—the
glia cells—are influenced,” explains Hans Wandall, associate professor.
Neurofibromatosis can cause deformity
The new results also influence our understanding of
neurofibromatosis. This is a heritable disorder that results in unsightly tumors—so-called
neurofibromas—in the nerves and skin. The disease affects approximately 20 people
out of 100,000 and varies from mild to severe cases with decided deformities.
The condition also affects the bones and often causes learning problems: “When
you get closer to an understanding of the mechanisms that result in a certain
disease, naturally it is easier to influence the disease process in the form of
drug development in the longer term. Neurofibromatosis is not a terminal
disease, but it very much affects the life quality of the people who have it
because the symptoms are so noticeable,” explains Ole Kjærulff. Hans
Wandall adds that the disease is also associated with certain types of cancer,
particularly in the brain.
