Enzyme and graft combo restores lung function after spinal injury
Until the last few decades, it was generally thought that damage to the spinal cord was permanent, as the nerves within our vertebrae stubbornly resist regrowing severed connections after injuries. But a number of studies have helped us understand why exactly it is that the nerves refuse to grow, raising the prospect that we could use this knowledge to intervene and help repair damage to the spine. In the latest indication that progress is being made in these efforts, researchers have used a combination of enzyme treatments and grafts to restore breathing activity in rats that had had their spinal connections completely severed.
Although spinal injuries can kill nerve cells at the site of damage, the bigger problem is that they sever the connections among nerves that are needed to relay messages within the spinal column and send them on to the brain. Once severed, these connections (formed by cellular structures called axons), tend not to regrow—at least not in the spine. But that’s not because axons are fundamentally opposed to regrowing, since they do re-establish connections in the periphery of the body, allowing feeling to return to skin that has been deadened by surgery, for example.