Item Type: | Article |
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Title: | Neuroprotective role of bradykinin because of the attenuation of pro-inflammatory cytokine release from activated microglia |
Creators Name: | Noda, M., Kariura, Y., Pannasch, U., Nishikawa, C., Wang, L., Seike, T., Ifuku, M., Kosai, Y., Wang, B., Nolte, C., Aoki, S., Kettenmann, H. and Wada, K. |
Abstract: | Bradykinin (BK) has been reported to be a mediator of brain damage in acute insults. Receptors for BK have been identified on microglia, the pathologic sensors of the brain. Here, we report that BK attenuated lipopolysaccharide (LPS)-induced release of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta from microglial cells, thus acting as an anti-inflammatory mediator in the brain. This effect was mimicked by raising intracellular cAMP or stimulating the prostanoid receptors EP2 and EP4, while it was abolished by a cAMP antagonist, a prostanoid receptor antagonist, or by an inhibitor of the inducible cyclooxygenase (cyclooxygenase-2). BK also enhanced formation of prostaglandin E2 and expression of microsomal prostaglandin E synthase. Expression of BK receptors and EP2/EP4 receptors were also enhanced. Using physiological techniques, we identified functional BK receptors not only in culture, but also in microglia from acute brain slices. BK reduced LPS-induced neuronal death in neuronmicroglia co-cultures. This was probably mediated via microglia as it did not affect TNF-alpha-induced neuronal death in pure neuronal cultures. Our data imply that BK has anti-inflammatory and neuroprotective effects in the central nervous system by modulating microglial function. |
Keywords: | Bradykinin, Lipopolysaccharide, Microglia, Prostaglandin, Tumor necrosis factor-alpha, Animals, Mice, Rats |
Source: | Journal of Neurochemistry |
ISSN: | 0022-3042 |
Publisher: | Blackwell Publishing |
Volume: | 101 |
Number: | 2 |
Page Range: | 397-410 |
Date: | April 2007 |
Official Publication: | https://doi.org/10.1111/j.1471-4159.2006.04339.x |
PubMed: | View item in PubMed |
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