Revisiting an Old Antimicrobial Drug: Amphotericin B Induces Interleukin-1–Converting Enzyme as the Main Factor for Inducible Nitric-Oxide Synthase Expression in Activated Endothelia
- Christoph Viktor Suschek1,
- Eckhard Bonmann3,
- Anna Kapsokefalou1,
- Karsten Hemmrich1,
- Hartmut Kleinert4,
- Ulrich Förstermann4,
- Klaus-Dietrich Kröncke1,
- Csaba Mahotka2 and
- Victoria Kolb-Bachofen1
- 1Research Group Immunobiology (C.V.S., A.K., K.H., K.-D.K., V.K.-B.) and 2Institute of Pathology (C.M.), Heinrich-Heine-University of Düsseldorf, Düsseldorf, Germany; 3Neurologische Klinik der Ruprecht-Karls-Universität, Heidelberg, Germany (E.B.); and4Department of Pharmacology, Johannes Gutenberg University, Mainz, Germany (H.K., U.F.)
- Dr. Christoph V. Suschek, Research Group Immunobiology, Heinrich-Heine-University, P.O. Box 101007, D-40001 Düsseldorf, Germany. E-mail:suschek{at}uni-duesseldorf.de
Abstract
We have investigated the impact of the widely used antifungal agent Amphotericin B (AmB) on cytokine activated aortic endothelial cells (AEC) and their inflammatory response as monitored by cytokine and inducible nitric-oxide synthase (iNOS) expression as well as high-output nitric oxide synthesis. Because both blood-borne infections and systemically administered drugs will first encounter vessel lining endothelial cells, this cell type represents an important participant in innate immune reactions against xenobiotics. Culturing cytokine-activated AEC in the presence of 1.25 μg/ml AmB, a concentration equivalent to serum levels during patient treatment, we find increases in iNOS promoter activity up to 120%, in iNOS mRNA or protein expressions by factors of up to 3.5 ± 1.1, and in iNOS activity of up to 180% compared with cells with cytokines only. In parallel, a strong increase in endothelial interleukin (IL)-1β–converting enzyme (ICE) and IL-1β expression and activity was observed. Specific inhibition of ICE activity or IL-1β functionality significantly reduces expression and activity of the iNOS to control values. Because ICE activity is essential for the endogenous synthesis of active IL-1β, ICE overexpression represents the key signal in the AmB-induced and IL-1β–mediated effects on iNOS activity. In summary, in endothelial cells, AmB strongly augments cytokine-induced iNOS expression and activity by increasing the expression and activity of the ICE. This adjuvant activity for augmented endogenous cytokine processing adds to the efficacy of the antimycotic activity of AmB. Furthermore, our data underline the relevance of the endothelial iNOS as a potent effector of the innate immune system.
Footnotes
-
This work was supported by grant SFB503 A3 from the Deutsche Forschungsgemeinschaft (to V.K.-B.).
- Abbreviations:
- AmB
- amphotericin B
- TNF
- tumor necrosis factor
- IL
- interleukin
- iNOS
- inducible nitric-oxide synthase
- ICE
- interleukin-1β–converting enzyme
- IFN
- interferon
- ELISA
- enzyme-linked immunosorbent assay
- LPS
- lipopolysaccharide
- eNOS
- endothelial nitric-oxide synthase
- FCS
- fetal calf serum
- RPMI
- Roswell Park Memorial Institute
- IEC
- islet endothelial cells
- AEC
- aorta endothelial cells
- DOC
- desoxycholate
- PBS
- phosphate-buffered saline
- PCR
- polymerase chain reaction
- GAPDH
- glyceraldehyde-3-phosphate dehydrogenase
- MOPS
- 3-(N-morpholino)propanesulfonic acid
- EPR
- electron paramagnetic resonance
- kb
- kilobase(s)
- RT
- reverse transcription
- NMA
- NG-monomethyl-l-arginine
- YVAD
- N-acetyl-Tyr-Val-Ala-Asp-aldehyde, an ICE inhibitor
- ZVAD
- N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone pan-caspase inhibitor
-
- Received April 15, 2002.
- Accepted July 12, 2002.
- The American Society for Pharmacology and Experimental Therapeutics
