Cajal-Retzius cell loss and amyloidosis in Alzheimer’s disease
Cajal-Retzius cells are reelin-secreting neurons in the marginal zone of the neocortex and hippocampus. However, the relationship between Cajal-Retzius cells and Alzheimer’s disease is unknown. Dr. Jinbo Deng and team from Henan University in China revealed that the number of Cajal-Retzius cells markedly reduced with age in both wild type and in mice over-expressing the Swedish double mutant form of amyloid precursor protein 695 (transgenic (Tg) 2576 mice).
The decline in Cajal-Retzius cells in Tg2576 mice was found to occur concomitantly with the onset of Alzheimer’s disease amyloid pathology and related behavioral defcits. Overall, these data, published in the Neural Regeneration Research (Vol. 9, No. 4, 2014), indicated that Cajal-Retzius cell loss occurred with the onset and development of Alzheimer’s disease.
Article: ” Characterization of hippocampal Cajal-Retzius cells during development in a mouse model of Alzheimer’s disease (Tg2576),” by Dongming Yu1, Wenjuan Fan2, Ping Wu1, Jiexin Deng1, Jing Liu1, Yanli Niu1, Mingshan Li1, Jinbo Deng1 (1 Institute of Neurobiology, School of Life Science, Henan University, Kaifeng, Henan Province, China; 2 Laboratory of Molecular Medicine, Luohe Medical College, Luohe, Henan Province, China)
Yu DM, Fan WJ, Wu P, Deng JX, Liu J, Niu YL, Li MS, Deng JB. Characterization of hippocampal Cajal-Retzius cells during development in a mouse model of Alzheimer’s disease (Tg2576). Neural Regen Res. 2014;9(4):394-401.
Cajal -Retzius cell
From Wikipedia, the free encyclopedia
The term Cajal – Retzius cells (CR cells) has nowadays been used to identify an heterogeneous population of morphologically and molecularly distinct reelin-producing cell types in the marginal zone/layer I of the developmental cerebral cortex and in the immature hippocampus of different species and at different times during embryogenesis and postnatal life.
These cells were discovered by two scientists, Cajal and Retzius, at two different times and in different species. They are originated in the developing brain in multiple sites within the neocortex and hippocampus. From there, CR cells experience migration through the marginal zone, originating the layer I of the cortex.
As these cells are involved in the correct organization of the developing brain, there are several studies implicating CR cells in neurodevelopmental disorders, especially Alzheimer’s, schizophrenia, bipolar disorder, autism, lissencephaly and temporal lobe epilepsy.
Called also: horizontal cells of Cajal-Retzius (Sievers and Raedler, 1981). This term pertains to a class of neurons of the embryonic marginal zone (prospective layer I) of the neocortex and hippocampus of all amniotes. These cells possess radial ascending processes that contact the pial surface, and a horizontal axon plexus located in the deep marginal zone. Cajal-Retzius cells are generated in several focal sites at the borders of the developing pallium and are redistributed by tangential migration (Bielle et al, 2005; Hevner et al, 2003). The migration process has been shown to involve the chemokine CXCL12 and its receptor CXCR4 (Paredes et al, 2006; Borrell and Marin, 2006).
Cells that have been described as Cajal-Retzius cells differ in their morphologies and connections, and it not clear whether these cells are all identical (for a study of gene expression patterns in Cajal-Retzius cells see also Yamazaki et al, 2004). Some of these cells have been described as Cajal cells, others as Retzius cells (Meyer et al, 1999). The term Cajal-Retzius cells is used now for cells in the marginal zone that secrete Reelin, the product of the reeler gene (Ogawa et al, 1995; D’Arcangelo et al, 1995, 1997; Ikeda and Terashima, 1997; Meyer and Goffinet, 1998; Meyer et al, 1998, 1999).
The exact functional role of Cajal-Retzius cells in the developing brain still remains to be elucidated (Sarnat and Flores-Sarnat, 2002; Soriano and Del Rio, 2005). Cajal-Retzius cells show excitability and express a variety of neurotransmitter receptors, implying that they are integrated in the neonatal cortical network (Mienville, 1999). These cells have been described to act as pioneer neurons of layer I of the cortex and are involved in neuronal migration and synaptogenesis. Soriano et al (1997) have shown that Cajal-Retzius cells regulate the radial glial cell phenotype in the adult and developing cerebellum and alter granule cell migration. Cajal-Retzius cells and reelin have been shown to be essential for the formation of layer-specific hippocampal connections. Yoshida et al (2006) have reported that massive loss of Cajal-Retzius cells does not disrupt neocortical layer order. Cell ablation of Cajal-Retzius cells in organotypic slice cultures of hippocampus have been shown to prevent the ingrowth of entorhinal but not of commissural afferent neurons. Inhibition of Reelin expression and the analysis of reeler mutant mice shows dramatic abnormalities in the development of entorhinal afferents (Del Rio et al, 1997). Super et al (2000) have demonstrated that Cajal-Retzius cell cell ablation arrests migration of late-generated neurons destined to cortical layers II-III, dramatically decreases the number of radial glial apical processes, and increases the number of maturing astrocytes.
Yamazaki et al (2004) have reported a genome-wide expression profile of cortical Cajal-Retzius cells at embryonic and postnatal periods.
Cajal-Retzius cells have been shown to possess the capacity to express the proteins listed below. Please note the following general observations, which practically apply to all cell types: expression may be influenced by tissue localization, may occur only in discrete subpopulations of cells, may vary between established cell lines, primary cells, embryonic cells, mature cells, fully differentiated cells, activated cells, non-activated cells or growth conditions (confluent vs. sparse cultures), may be influenced by various disease states (including cancer environment), and may differ between species.
Note also: expression profile information lists entities only for which there is an entry in COPE or one of its subdictionaries.
Neural Regeneration Research