Dentate Granule Cells In Temporal Lobe Epilepsy is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
DGCs show aberrant sprouting in TLE.
| Property | Value |
|---|---|
| Category | Hippocampus |
| Location | Dentate gyrus |
| Cell Type | Granule cells |
| Projection | Mossy fibers to CA3 |
| Taxonomy | ID | Name / Label |
|---|---|---|
| Cell Ontology (CL) | CL:0000120 | granule cell |
The study of Dentate Granule Cells In Temporal Lobe Epilepsy has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Aberrant mossy fiber sprouting creates recurrent excitatory circuits that lead to excessive glutamate signaling through AMPA receptors[1]. This chronic excitation triggers downstream calcium overload and oxidative stress, accelerating neuronal dysfunction in the dentate gyrus[2].
Elevated intracellular calcium activates calcium-dependent proteases, kinases, and phosphatases that alter synaptic plasticity and promote epileptogenesis. The loss of calcium buffering via calbindin (CALB1) and calretinin (CALB2) in DGCs correlates with hyperexcitability[3].
Seizure activity induces mitochondrial permeability transition, ATP depletion, and reactive oxygen species (ROS) generation in dentate granule cells. This energy crisis impairs the sodium-potassium pump and disrupts neuronal homeostasis[4].
IL-1β, TNF-α, and IL-6 released from activated microglia create a pro-inflammatory milieu that lowers seizure threshold. Astrocyte reactivity also disrupts potassium buffering and glutamate uptake[5].
DGCs are generated throughout life in the subgranular zone. Chronic epilepsy reduces neurogenesis while promoting abnormal integration of new neurons into hippocampal circuits[6].
| Gene/Protein | Role in DGCs | Association |
|---|---|---|
| BDNF | Neurotrophic support, synaptic plasticity | Elevated in seizures, promotes sprouting |
| CREB1 | Transcription factor, memory formation | Dysregulated in chronic TLE |
| NPAS3 | Transcription factor, neurodevelopment | Risk gene for TLE |
| CALB1 | Calcium buffering | Protective; reduced in epileptic DGCs |
| CALB2 (Calretinin) | Calcium buffering | Marker for immature DGCs |
| GSK3B | Kinase, tau phosphorylation | Hyperactive during seizures |
| AMPA Receptors | Fast excitatory neurotransmission | Elevated subunit expression in sprouting |
Sutula TP, Golarai G. Axonal sprouting and epileptogenesis. Epilepsy Res Suppl. 1992. ↩︎
Sharma AA. Altered AMPA receptor subunit expression in temporal lobe epilepsy. Ann Neurol. 2007. ↩︎
Freiman TM. Calcium binding proteins in hippocampal sclerosis. Brain Pathol. 2011. ↩︎
Kudin AP. Mitochondrial dysfunction in epileptic hippocampus. J Neurosci Res. 2002. ↩︎
Vezzani A, French J. The role of neuroinflammation in temporal lobe epilepsy. Nat Rev Neurol. 2013. ↩︎
Parent JM. Aberrant neurogenesis in temporal lobe epilepsy. Brain Res. 2013. ↩︎