Science pic: What can these mushroom-like structures tell us about brain disease?

Mushroom-like “spines” on a CA1 pyramidal neuron in the hippocampus, the brain region that is primarily involved with learning and memory. Image: Ivan Galimberti/Novartis

These might seem like stubby, green mushrooms sprouting from a tree root. But they’re actually structures on neurons called spines that are critical for learning and memory.

Spines play an important role in communication between cells in the brain. They’re sprinkled along dendrites— long and spindly extensions that reach out from the bodies of neurons, seeking electrical signals. Spines are where the signals are received and where synapses form with other neurons. They’re constantly being produced, strengthened and eliminated as we process conversations and other life experiences.

Scientists at the Novartis Institutes for BioMedical Research (NIBR) are studying how spines are affected by neurodevelopmental diseases such as autism and schizophrenia.

“In certain disease states we see a reduction in the total number of dendritic spines, which is a sign of synaptic immaturity,” explains Ivan Galimberti, an investigator leading these studies in NIBR’s Developmental & Molecular Pathways group.

The shape of the spines is also important. Researchers use words like “stubby” and “filipodial” to describe them. In this image, two stubby spines grow from the top of the dendrite, indicating mature synapses. In contrast, a few small, thin spines grow from the bottom. These filipodial formations are synaptically immature. A healthy dendrite contains an even mix of stubby and filipodial projections.

DMP researchers use fluorescent microscopy imaging to monitor the quantity and shape of dendritic spines in the context of brain disease. Researchers can evaluate potential treatments based on their ability to restore dendritic spines to a healthy state. Counting green “mushrooms” is aiding efforts to discover new medicines for neurodevelopmental diseases.