An acidic fibroblast growth factor-like factor secreted into the brain cell culture medium upregulates apoE synthesis, HDL secretion and cholesterol metabolism in rat astrocytes.
Production and release of apolipoprotein (apo) E and cholesterol were highly upregulated in the astrocytes prepared by 1-week secondary culture after 1-month primary culture of rat fetal brain cells (M/W cells) in comparison to the cells prepared by a conventional method of 1-week primary and 1-week secondary culture (W/W cells). Both cell preparations were mostly composed of astrocytes with small population of other glial cells, except that type-2 astrocyte-like cells accounted for 5-15% of M/W cells indicating more activated and/or matured status. The conditioned medium of the 1-month primary culture stimulated W/W cells to increase the release of apoE and cholesterol into the medium. The treatment of W/W cells by acidic fibroblast growth factor (aFGF) similarly upregulated biosyntheses and release of apoE and cholesterol. The effect of the conditioned medium was completely inhibited by pretreatment with an anti-aFGF antibody. The increase of the aFGF message was demonstrated in the brain cells after 1-month primary culture. The findings suggested that an aFGF-like trophic factor upregulates biosynthesis and secretion of apoE-high density lipoprotein (HDL) in astrocytes probably by autocrine stimulation in this culture system. Since this cytokine is highly expressed in the development or post-injury period of the brain, it putatively activates intercellular cholesterol transport to support construction or recovery of the brain.
Ueno
Sachiko
S
Psychiatry and Cognitive-Behavioral Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi 1, Mizuho-cho, Japan.
Ito
Jin-ichi
J
Nagayasu
Yuko
Y
Furukawa
Toshiaki
T
Yokoyama
Shinji
S
D000818:Animals; D001057:Apolipoproteins E / Q000096:biosynthesis*; D001253:Astrocytes / Q000378:metabolism*; D015153:Blotting, Western; D002478:Cells, Cultured; D008076:Cholesterol, HDL / Q000096:biosynthesis*; D003470:Culture Media; D017077:Culture Media, Conditioned; D016220:Fibroblast Growth Factor 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051381:Rats; D015854:Up-Regulation
D001057:Apolipoproteins E; D008076:Cholesterol, HDL; D003470:Culture Media; D017077:Culture Media, Conditioned; D016220:Fibroblast Growth Factor 1