APOLIPOPROTEIN-E GENE-EXPRESSION IN ASTROCYTES - DEVELOPMENTAL PATTERN AND REGULATION

APOLIPOPROTEIN E (APoE) is involved in brain development and repair. I n order to investigate the contribution of astrocytes to ApoE gene exp ression, we investigated ApoE mRNA levels in mouse brain and in astrog lial primary cultures during postnatal development and in two differen t trauma models. A biphasic developmental pattern was observed consist ing in an increased expression during the first 2 weeks and a decrease in the later stages. A similar pattern was obtained in highly enriche d primary cultures, suggesting ApoE mRNA location in the astroglial po pulation and an important role for ApoE in astroglial development and/ or function. ApoE gene expression could be modulated in culture by adm inistration of lipopolysaccharides (LPS) which mimics a bacterial infe ction, or in reactive astrocytes consequent to a chemically induced le sion, suggesting that ApoE might be involved in the inflammatory event s consequent to both situations. These results underline the importanc e of astrocytes in regenerative processes.