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and Interleukin 1
Enhance the
Cortisone/Cortisol Shuttle
By
From the Division of Nephrology, University Hospital of Berne, 3010 Berne, Switzerland
Endogenously released or exogenously administered glucocorticosteroids are relevant hormones for controlling inflammation. Only 11
-hydroxy glucocorticosteroids, but not 11-keto
glucocorticosteroids, activate glucocorticoid receptors. Since we found that glomerular mesangial cells (GMC) express 11
-hydroxysteroid dehydrogenase 1 (11
-OHSD1), which interconverts 11-keto glucocorticosteroids into 11
-hydroxy glucocorticosteroids (cortisone/cortisol
shuttle), we explored whether 11
-OHSD1 determines the antiinflammatory effect of glucocorticosteroids. GMC exposed to interleukin (IL)-1
or tumor necrosis factor
(TNF-
) release group II phospholipase A2 (PLA2), a key enzyme producing inflammatory mediators.
11
-hydroxy glucocorticosteroids inhibited cytokine-induced transcription and release of
PLA2 through a glucocorticoid receptor-dependent mechanism. This inhibition was enhanced
by inhibiting 11
-OHSD1. Interestingly, 11-keto glucocorticosteroids decreased cytokine-induced PLA2 release as well, a finding abrogated by inhibiting 11
-OHSD1. Stimulating
GMC with IL-1
or TNF-
increased expression and reductase activity of 11
-OHSD1. Similarly, this IL-1
- and TNF-
-induced formation of active 11
-hydroxy glucocorticosteroids
from inert 11-keto glucocorticosteroids by the 11
-OHSD1 was shown in the Kiki cell line
that expresses the stably transfected bacterial
-galactosidase gene under the control of a glucocorticosteroids response element. Thus, we conclude that 11
-OHSD1 controls access of 11
-hydroxy glucocorticosteroids and 11-keto glucocorticosteroids to glucocorticoid receptors and
thus determines the anti-inflammatory effect of glucocorticosteroids. IL-1
and TNF-
upregulate specifically the reductase activity of 11
-OHSD1 and counterbalance by that mechanism
their own proinflammatory effect.
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