Dentate gyrus molecular layer interneurons (MML cells) are a critical component of the hippocampal circuitry that modulates information flow through the dentate gyrus. These inhibitory neurons are located in the molecular layer of the dentate gyrus and play essential roles in regulating synaptic plasticity, memory encoding, and pattern separation. In Alzheimer's disease (AD), molecular layer interneurons are affected early in the disease process, contributing to hippocampal dysfunction and memory deficits. Understanding the function of these neurons provides insight into the neural circuits underlying learning and memory and how they degenerate in neurodegenerative diseases. [1]
The dentate gyrus molecular layer contains various types of inhibitory interneurons that modulate the input from the entorhinal cortex (perforant path) to the dentate granule cells. Molecular layer interneurons (MML cells) are characterized by their horizontal dendritic orientation and their location in the outer molecular layer. These neurons receive input from the lateral entorhinal cortex and provide feedforward inhibition to granule cells and other interneurons, shaping the excitatory signals that drive hippocampal encoding. [2]
| Taxonomy | ID | Name / Label |
|---|---|---|
| Cell Ontology (CL) | CL:4023062 | dentate gyrus neuron |
| Database | ID | Name | Confidence | [3]
|----------|----|------|------------| [4]
| Cell Ontology | CL:4023062 | dentate gyrus neuron | Medium | [5]
Molecular layer interneurons are among the first hippocampal neurons affected in AD: [6]
The study of Dentate Gyrus Molecular Layer Interneurons 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.
Freund TF, Buzsáki G. Interneurons of the hippocampus. Hippocampus. 1996. 1996. ↩︎
Amaral DG, Scharfman HE, Lavenex P. The dentate gyrus: fundamental neuroanatomical organization. Prog Brain Res. 2007. 2007. ↩︎
Hyman BT, Van Hoesen GW, Damasio AR, Barnes CL. Alzheimer's disease: cell-specific pathology isolates the hippocampal formation. Science. 1984. 1984. ↩︎
Kelley CM, Powers BE, Velazquez R, et al. Medial septal nucleus, diagonal band of Broca, and basalis prosencephalon in Alzheimer's disease. J Neuropathol Exp Neurol. 2020. 2020. ↩︎
Scharfman HE. The dentate gyrus as a filter for new memories. Prog Brain Res. 2007. 2007. ↩︎
Yassa MA, Stark CE. Pattern separation in the hippocampus. Trends Neurosci. 2011. 2011. ↩︎