Colabomycin E was isolated and purified from the natural producer Streptomyces aureus SOK1/5-04 by extraction of post-fermentation medias and mycelia with organic solvents and multiple subsequent liquid chromatography purification steps and crystallization. Monocytes/macrophages were cultured in RPMI1640 with 10% fetal calf serum and then stimulated with TNF-α (20ng/ml) under serum free conditions in the presence or absence of colabomycin E. The total mRNA was extracted from cultured monocytes/macrophages with RNAeasy Plus Mini Kit (Qiagen) and quantitative RT-PCR (SABiosciences) was used for the evaluation of 84 different gene expressions in TNF alpha and colabomycin E stimulated cultures and compared to unstimulated cells. The concentrations of cytokines and chemokines in culture supernatants of monocytes and THP-1 cells were measured by ELISA or Luminex.
In THP-1 cells, Colabomycin E inhibited TNF alpha induced mRNA expression of several proinflammatory genes including IL-1β, IL-6, TLR8, and MyD88. The effect was evident after 4h and 8h cultures and in some of the genes persisted for 24h. Furthermore, colabomycin E downregulated TNF alpha induced IL-1β, IL-6 and chemokine CXCL8/IL-8 release in a dose dependent manner from 0.25µM concentration. The secretion of IL-18 from THP-1 cells was only slightly upregulated by TNF alpha and not affected by colabomycin E. Our data suggest that colabomycin E is a potent transcription inhibitor of proinflammatory cytokines in human mononuclear phagocytes.
*Petrickova K et al. ChemBioChem 15:1334-45, 2014
Supported by IGA MZCR grant NT/13012-4 and by MH CZ - DRO („Institute for Clinical and Experimental Medicine – IKEM, IN 00023001“)