Is Mossy Fiber Sprouting a Potential Therapeutic Target for Epilepsy?

  title={Is Mossy Fiber Sprouting a Potential Therapeutic Target for Epilepsy?},
  author={Clarissa Fantin Cavarsan and Jackeline Moraes Malheiros and Clement Hamani and Imad M. Najm and Luciene Covolan},
  journal={Frontiers in Neurology},
Mesial temporal lobe epilepsy (MTLE) caused by hippocampal sclerosis is one of the most frequent focal epilepsies in adults. It is characterized by focal seizures that begin in the hippocampus, sometimes spread to the insulo-perisylvian regions and may progress to secondary generalized seizures. Morphological alterations in hippocampal sclerosis are well defined. Among them, hippocampal sclerosis is characterized by prominent cell loss in the hilus and CA1, and abnormal mossy fiber sprouting… 

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Does mossy fiber sprouting give rise to the epileptic state?

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Findings from stereological electron microscopy and rapamycin-delayed mossy fiber sprouting in rodent models of temporal lobe epilepsy suggest a persistent, homeostatic mechanism exists to maintain a set level of excitatory synaptic input to granule cells.

Different mossy fiber sprouting patterns in ILAE hippocampal sclerosis types

Mossy fiber sprouting in the dentate gyrus

Aberrant sprouting of granule cell axons is a common feature in temporal lobe epilepsy and recent progress in suppressing mossy fiber sprouting might help address its functional consequences.

Rapamycin Suppresses Mossy Fiber Sprouting But Not Seizure Frequency in a Mouse Model of Temporal Lobe Epilepsy

Findings are consistent with the hypotheses that hilar neuron loss and ectopic granule cells might contribute to temporal lobe epileptogenesis and suggest mossy fiber sprouting is neither pro- nor anti-convulsant; however, there are caveats.

Circuit Mechanisms of Seizures in the Pilocarpine Model of Chronic Epilepsy: Cell Loss and Mossy Fiber Sprouting

The pilocarpine model of chronic seizures replicates several of the fea tures of human temporal lobe epilepsy and may be a useful model for studying this human condition, and the results suggest that even though a certain amount of cell loss in specific areas may be essential for chronic seizures to occur, excessive cell loss may hinder epileptogenesis.

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