Nervous Stress

People with major back injuries may be permanently paralysed because the neurons in the spinal cord can’t regenerate – unlike the peripheral neurons in other parts of the body. The ability of these neurons to self-repair is being studied by scientists, who recently discovered a master gene, called HIF-1α, which triggers growth factors when activated by low oxygen levels in stress conditions. In experiments on mice, damaged neurons started to regrow after oxygen in the animals’ air supply was reduced for short periods. Pictured are sections of sciatic nerve, showing nerve fibres, unstained and stained blue, regenerating to the right of the damaged area (dotted line). The repair process is more advanced in the sections from a normal mouse, pictured at the top, which is evident from higher levels of a neuron growth protein, SCG10 (stained yellow) than those at the bottom, from a mouse genetically engineered to lack HIF-1α.

Written by Mick Warwicker

Mick Warwicker

Writer

A freelance communications consultant and writer, Mick specialises in science and education. A science graduate and award-winning print and broadcast journalist, he was Head of Communications at Newcastle University from 2000–2011.

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• Image adapted from work by Yongcheol Cho and colleagues
• Department of Anatomy and Neurobiology, School of Medicine, Washington University in St. Louis, USA
• Image copyright Elsevier 2015
• Published in Neuron, October 2015