Nerve cell findings may aid understanding of movement disorders

Professor Tom Gillingwater (Centre for Discovery Brain Sciences, University of Edinburgh) and colleagues, along with researchers the University of Exeter, have made fresh insights into the links between nerve and muscle cells which could transform our understanding of the human nervous system and conditions relating to impaired movement. They studied Neuromuscular Junctions (NMJ) - a type of cell connection that allows electrical and chemical messages to flow from nerve to muscle cells, enabling motion.

The team collected healthy tissue frm 20 donors undergoing surgical amputation. They were then able to use cutting-edge imaging to study 3000 of cell connections called Neuromuscular Junctions (NMJ). The study compared the cellular and molecular architecture of these human NMJs  with animal models. They were able to highlight differences in the structure and make up of human NMJs compared with those of mice and rats, which are routinely used in studying neuromuscular diseases. Details of the anatomy of human NMJs that had not been seen before were revealed in this study, and it was found that human NMJs were much smaller and frailer than those found in other mammals.

The results shed light into conditions where these connections break down, such as motor neurone disease, which can lead to severe problems with walking and reflexes. The research team also found that age had no effect on the health of NMJs - a finding that could help doctors understand disease-related changes in the nervous system that affect older adults.

Tom Gillingwater (Professor of Anatomy, University of Edinburgh’s Centre for Discovery Brain Sciences), who co-led the study, said: “Together our findings provide unique insights into the structure of the human nervous system, identifying features that set us apart from other mammals. Our next steps will be to use these vital insights to understand how the NMJ breaks down in human patients with neuromuscular conditions such as motor neurone disease.”

Christian Soeller (Professor of Physical Cell Biology, University of Exeter’s Physics department and Living Systems Institute), who co-led the study, said: “The age-old adage of ‘seeing is believing’ is particularly fitting for this study. The human nerve connections that we saw – using new microscopy methods crucial for this study – were very different from what was previously thought.”