Topic: Neuroscience

Researchers at the University of Cambridge created tiny lab-grown brain and spinal cord systems to study nerve damage. They found that damaged axons can regrow under certain conditions, offering new hope for people with paralysis or neurological diseases.

Scientists have long believed that nerve damage is permanent once it occurs. However, a team at the University of Cambridge has made a groundbreaking discovery that challenges this notion. Using miniature human brain and spinal cord models, they found that damaged axons can regrow under certain conditions.

As our bodies develop from embryos to infants, neurons form complex networks between the brain and spinal cord. These signals travel through long nerve fibers called axons, allowing us to control muscle movement. However, over time, the central nervous system loses its ability to regrow damaged axons, leading to permanent disabilities like paralysis.

The University of Cambridge team created miniature human brain models using stem cells taken from patients in 2021. These pea-sized 'brain organoids' resembled parts of the cerebral cortex and allowed researchers to study molecular changes linked to motor neurone disease and explore ways to prevent them. In a new study, they expanded on this work by building a miniature version of the connected human brain and spinal cord system.

The team observed axons from the brain tissue growing across the gap and connecting with the spinal cord tissue, creating a functional neural circuit that triggered contractions in tiny clusters of muscle cells. They found that until about day 150 of development, roughly corresponding to the middle stage of pregnancy, damaged axons could still regrow.

However, after this point, the neurons showed a major decline in their ability to regenerate. The team analyzed gene activity in neurons that connect the brain and spinal cord and discovered a network of genes that acts like a biological switch, limiting axon growth as neurons mature and form synapses.

Why It Matters

This breakthrough discovery has significant implications for people with paralysis or neurological diseases. It offers new hope for regaining control over damaged nerve fibers and improving the quality of life for those affected.

Key Facts

• Scientists at the University of Cambridge created miniature human brain and spinal cord models to study nerve damage.
• The team found that damaged axons can regrow under certain conditions, challenging the notion that nerve damage is permanent.
• The study revealed a network of genes that acts like a biological switch, limiting axon growth as neurons mature and form synapses.

Key Terms

Axons

Long nerve fibers that allow neurons to send messages and control muscle movement

Implications

This breakthrough discovery has significant implications for people with paralysis or neurological diseases. It offers new hope for regaining control over damaged nerve fibers and improving the quality of life for those affected.