Exosomes protect the brain from epilepsy
Researchers at the Texas A&M University College of Medicine, working under the guidance of Professor Ashok K. Shetty and Professor Darwin J. Prockop, demonstrated in animal models that intranasal administration of exosomes of mesenchymal stem cells (MSCs) reduces the severity of brain damage associated with epileptic status.
An epileptic status is one epileptic seizure lasting more than 30 minutes or a series of seizures between which the patient does not regain consciousness. In the absence of rapid intervention, even one such episode can cause serious brain damage, impaired cognitive function and memory loss.
To relieve the epileptic status, benzodiazepine class tranquilizers are used, as well as the anticonvulsant drug gidantoin. However, very often these drugs are not available, especially if the patient has not been diagnosed with epilepsy before, which is typical for 75% of cases. Moreover, in 30% of cases, these drugs are ineffective. To date, there are no non-invasive methods that would stop the inflammatory cascade and the formation of abnormal interneuronal connections, or epileptogenesis that develops after a convulsive episode.
The authors have developed an alternative completely non-invasive approach to solving this problem, which consists in the use of a nasal spray containing exosomes or extracellular vesicles with anti-inflammatory properties isolated from mesenchymal stem cells of the bone marrow.
As part of the study, mice with simulated epileptic status were injected intranasally twice within 24 hours with a spray containing exosomes of mesenchymal stem cells labeled with a red fluorescent membrane dye. The first injection of the spray was carried out 2 hours after the onset of the convulsive episode. Six hours after the first injection, the labeled exosomes were registered in the hippocampus, the region of the brain responsible for memorization.
The action of exosomes weakened the manifestations of neuronal inflammation and stopped abnormal neurogenesis in the hippocampus. Their neuroprotective effect was sufficient to prevent the development of cognitive and memory disorders, as well as the development of chronic epilepsy, into which the epileptic status often passes without timely medical intervention.
Despite the promising results, the researchers caution that it is still very early to talk about the introduction of a new approach into clinical practice and there is still a lot of work to be done before clinical trials are conducted. However, it should be remembered that the inflammation of the brain caused by seizures is similar to the inflammation observed in the late stages of other diseases, including Alzheimer's disease, Parkinsonism, multiple sclerosis and traumatic injuries. Therefore, the potential scope of the new approach is very extensive.
Article by Qianfa Long et al. Intranasal MSC-derived A1-exosomes ease inflammation, and prevent abnormal neurogenesis and memory dysfunction after status epilepticus is published in the journal Proceedings of the National Academy of Sciences.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Texas A&M College of Medicine: Preventing seizure-caused damage to the brain.
18.04.2017