Article

Apolipoprotein D expression in human brain reactive astrocytes.

Departamento de Morfología y Biología Celular, Facultad de Biología y Medicina, Universidad de Oviedo, España.
Journal of Histochemistry and Cytochemistry (Impact Factor: 2.26). 11/2003; 51(10):1285-90. DOI: 10.1177/002215540305101005
Source: PubMed

ABSTRACT Astrocytosis is a hallmark of damage that frequently occurs during aging in human brain. Astrocytes proliferate in elderly subjects, becoming hypertrophic and highly immunoreactive for glial fibrillary acidic protein (GFAP). These cells are one type that actively responds in the repair and reorganization of damage to the neural parenchyma and are a source of several peptides and growth factors. One of these biomolecules is apolipoprotein D (apo D), a member of the lipocalin family implicated in the transport of small hydrophobic molecules. Although the role of apo D is unknown, increments in brain apo D expression have been observed in association with aging and with some types of neuropathology. We have found an overexpression of apo D mRNA in reactive astrocytes by in situ hybridization in combination with immunohistochemistry for apo D in normal aged human brains. The number of double-labeled cells varied according to the cerebral area and the gliosis grade. The possible significance of this increased synthesis of apo D in reactive astrocytes is discussed in relation to the role of apo D in aging and in glial function.

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