Dexamethasone induces an increase in intracellular and membrane-associated lipocortin-1 (annexin-1) in rat astrocyte primary cultures
Abstract
1. The antiinflammatory actions of glucocorticoid steroids are thought to occur through induction of the protein lipocortin-1 (LC-1; annexin-1). The purpose of the current study was to investigate whether astrocytic LC-1 content was increased in the presence of a synthetic glucocorticoid, dexamethasone. 2. Steroid-induced changes in cellular levels of LC-1 in astrocytes were determined by electrotransfer and immunoblotting techniques. Separate cell fractions were investigated to study the influence of dexamethasone on astroglial LC-1 content. The effect of culture state on LC-1 expression was also examined. 3. Intracellular LC-1 content was found to decrease after initiation of culture, with a substantial rise in both cell proliferation and LC-1 expression occurring after the replenishment of medium containing steroid-free serum. A further increase in intracellular LC-1 occurred upon incubation with dexamethasone. The glucocorticoid-induced change in intracellular LC-1 was a time-dependent event and coincided with an increase in membrane-associated LC-1. 4. The findings in this study indicate that astrocytic LC-1 content is influenced by cell culture conditions and, in the presence of glucocorticoid steroids, the cellular local...Continue Reading
References
Citations
Related Concepts
Related Feeds
Astrocytes
Astrocytes are glial cells that support the blood-brain barrier, facilitate neurotransmission, provide nutrients to neurons, and help repair damaged nervous tissues. Here is the latest research.