Adult hippocampal neurogenesis and sudden unexpected death in epilepsy: reality or just an attractive history?

Neurogenesis persists throughout life in the adult mammalian dentate gyrus and is regulated by several environmental, physiological, and molecular factors. Seizure activity also influences dentate granule cell neurogenesis. In these lines, studies of neurogenesis have demonstrated the presence of hilar-ectopic dentate granule cells after status epilepticus induced experimentally and that these cells are migrate aberrantly, abnormally integrated and hyperexcitable, contributing with this to seizure generation and/or propagation. As we know, epilepsy is the most common serious neurological condition and sudden unexpected death in epilepsy (SUDEP) is the most important direct epilepsy-related cause of death. Information concerning risk factors for SUDEP is conflicting, but high seizure frequency is a potential risk factor. Additionally, potential pathomechanisms for SUDEP are unknown, but it is very probable that cardiac arrhythmias during and between seizures or transmission of epileptic activity to the heart via the autonomic nervous system potentially play a role. Based on these facts, in this paper we postulate that aberrant neurogenesis could influence negatively the cardiovascular system of the patient with epilepsy leading to cardiac abnormalities and hence SUDEP.