A new intranasal spray could prevent damage caused by status epilepticus, according to research published in the Proceedings of the National Academy of Sciences (PNAS).
Status epilepticus (SE) is a prolonged seizure (lasting more than five minutes) that requires urgent treatment and hospital admission. If not ended quickly, just one episode can lead to neuronal death, cognitive impairment and memory loss, and it also renders a person more susceptible to developing epilepsy if they don’t already have it.
Tranquilizing drugs such as benzodiazepines are the usual treatment for SE, but they are ineffective approximately 30% of the time. Researchers in Texas have now developed an intranasal spray that is made up of tiny sacs (vesicles) secreted by a specific type of stem cell obtained from the bone marrow. These vesicles have anti-inflammatory properties. In the current study, the researchers aimed to investigate the effects of the new treatment on SE-induced damage.
To do this the team induced SE in young rodents for 2 h, and then administered them with either the new treatment or a type of placebo twice over 24 h (both intranasally). Looking closely at the brains of the animals at different time points post-SE, the researchers found that those receiving the active treatment had decreased loss of neurons and greatly reduced inflammation in the hippocampus (an important memory structure) compared with the placebo-treated animals. They noticed that this effect was long-lasting, and that the generation of new neurons in the hippocampus was sustained (whereas in the placebo-treated animals this was abnormal). Behavioural tests showed that memory and cognitive functions were preserved in the animals that received the treatment, but not in those that received the placebo. The new treatment also appeared to protect animals from developing chronic epilepsy.
Professor Ashok Shetty, Co-Senior Author on the paper comments:
“What is remarkable is that the animal models were rescued from long-term effects of the seizure-induced brain injury by a nasal spray.”
“In fact, the vesicles were able to move to the hippocampus in six hours, and their neuroprotection was enough to prevent loss of normal cognitive and memory function as well as abnormal neurogenesis, one of the substrates involved in formation of new memories.”
“There really hasn’t been anything non-invasive like this to stop the cascade of inflammation and abnormal neuronal wiring or epileptogenesis that occurs after a status epilepticus even.”
These results are very promising, and they could have implications for a number of neurological conditions, not just epilepsy. However, the authors urge caution because a lot more research is needed before the new treatment reaches clinical trials. We look forward to receiving further updates from them in the future.