RELN-expressing neuron density in layer I of the superior temporal lobe is similar in human brains with autism and in age-matched controls.

Abstract

Reelin protein (RELN) level is reduced in the cerebral cortex and cerebellum of subjects with autism. RELN is synthesized and secreted by a subpopulation of neurons in the developing cerebral cortex termed Cajal-Retzius (CR) cells. These cells are abundant in the marginal zone during cortical development, many die after development is complete, but a small population persists into adulthood. In adult brains, RELN is secreted by the surviving CR cells, by a subset of GABAergic interneurons in layer I, and by pyramidal cells and GABAergic interneurons in deeper cortical layers. It is widely believed that decreased RELN in layer I of the cerebral cortex of subjects with autism may result from a decrease in the density of RELN expressing neurons in layer I; however, this hypothesis has not been tested. We examined RELN expression in layer I of the adult human cortex and found that 70% of cells express RELN in both control and autistic subjects. We quantified the density of neurons in layer I of the superior temporal cortex of subjects with autism and age-matched control subjects. Our data show that there is no change in the density of neurons in layer I of the cortex of subjects with autism, and therefore suggest that reduced RELN expression in the cerebral cortex of subjects with autism is not a consequence of decreased numbers of RELN-expressing neurons in layer I. Instead reduced RELN may result from abnormal RELN processing, or a decrease in the number of other RELN-expressing neuronal cell types.

• Authors: Jasmin Camacho, Ehsan Ejaz, Jeanelle Ariza, Stephen C Noctor, Verónica Martínez-Cerdeño
• Journal: Neuroscience letters (Neurosci Lett) Vol. 579 Pg. 163-7 (Sep 05 2014) ISSN: 1872-7972 [Electronic] Ireland
• PMID: 25067827 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Chemical References

• Cell Adhesion Molecules, Neuronal
• Extracellular Matrix Proteins
• Nerve Tissue Proteins
• Reelin Protein
• RELN protein, human
• Serine Endopeptidases

Topics

• Adolescent
• Adult
• Autistic Disorder (metabolism, pathology)
• Cell Adhesion Molecules, Neuronal (biosynthesis)
• Cell Count
• Cerebral Cortex (metabolism, pathology)
• Extracellular Matrix Proteins (biosynthesis)
• Humans
• Middle Aged
• Nerve Tissue Proteins (biosynthesis)
• Neurons (metabolism, pathology)
• Pyramidal Cells (metabolism)
• Reelin Protein
• Serine Endopeptidases (biosynthesis)
• Temporal Lobe (metabolism, pathology)
• Young Adult