Depolarizing γ-aminobutyric acid contributes to glutamatergic network rewiring in epilepsy

Autor: Kourdougli, Nazim, Pellegrino, Christophe, Renko, Juho-Matti, Khirug, Stanislav, Chazal, Geneviève, Kukko-Lukjanov, Tiina-Kaisa, Lauri, Sari, Gaïarsa, Jean-Luc, Zhou, Liang, Peret, Angélique, Castren, Eero, Tuominen, Raimo, Crépel, Valérie, Rivera, Claudio
Přispěvatelé: PRA, Fanny, Institut de Neurobiologie de la Méditerranée [Aix-Marseille Université] (INMED - INSERM U901), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Développement et pathologie du motoneurone, Institut National de la Santé et de la Recherche Médicale (INSERM), Nanjing University of Posts and Telecommunications, Nanjing, China, Neuroscience Center, Developmental Biology Program, University of Helsinki, Epilepsie et ischémie cérébrale, Université de la Méditerranée - Aix-Marseille 2-Institut National de la Santé et de la Recherche Médicale (INSERM), Aix Marseille Université (AMU)
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Annals of Neurology
Annals of Neurology, Wiley, 2017, 81 (2), pp.251-265. ⟨10.1002/ana.24870⟩
ISSN: 0364-5134
1531-8249
Popis: International audience; Objective: Rewiring of excitatory glutamatergic neuronal circuits is a major abnormality in epilepsy. Besides the rewiring of excitatory circuits, an abnormal depolarizing c-aminobutyric acidergic (GABAergic) drive has been hypothesized to participate in the epileptogenic processes. However, a remaining clinically relevant question is whether early post-status epilepti-cus (SE) evoked chloride dysregulation is important for the remodeling of aberrant glutamatergic neuronal circuits. Methods: Osmotic minipumps were used to infuse intracerebrally a specific inhibitor of depolarizing GABAergic transmission as well as a functionally blocking antibody toward the pan-neurotrophin receptor p75 (p75 NTR). The compounds were infused between 2 and 5 days after pilocarpine-induced SE. Immunohistochemistry for NKCC1, KCC2, and ectopic recurrent mossy fiber (rMF) sprouting as well as telemetric electroencephalographic and electro-physiological recordings were performed at day 5 and 2 months post-SE. Results: Blockade of NKCC1 after SE with the specific inhibitor bumetanide restored NKCC1 and KCC2 expression, normalized chloride homeostasis, and significantly reduced the glutamatergic rMF sprouting within the dentate gyrus. This mechanism partially involves p75 NTR signaling, as bumetanide application reduced SE-induced p75 NTR expression and functional blockade of p75 NTR decreased rMF sprouting. The early transient (3 days) post-SE infusion of bumetanide reduced rMF sprouting and recurrent seizures in the chronic epileptic phase. Interpretation: Our findings show that early post-SE abnormal depolarizing GABA and p75 NTR signaling fosters a long-lasting rearrangement of glutamatergic network that contributes to the epileptogenic process. This finding defines promising and novel targets to constrain reactive glutamatergic network rewiring in adult epilepsy.
Databáze: OpenAIRE
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