ABSTRACT
Ebosin is a novel exopolysaccharide produced by Streptomyces sp.139 with remarkable activity against rheumatic arthritis in vivo. In this paper, we reported effects of Ebosin on the inflammatory cytokines including interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNFalpha) in THP-1 cells. With the special fluorogenic peptide as substrates, the enzymatic activities of interleukin-1beta converting enzyme (ICE) and TNFalpha-converting enzyme (TACE) were inhibited by Ebosin separately. Using the real-time reverse transcription polymerase chain reaction (real-time PCR), the mRNA synthesis of the three cytokines were identified decline separately by Ebosin. The secretion quantum of three cytokines in THP-1 cells with Ebosin was lower than that of normal THP-1 cells determined by ELISA assay and Western blotting. All of these results showed that Ebosin has remarkably suppressed synthesis of the three cytokines in THP-1 cells through different pathways. The primary study of Ebosin on anti-inflammation mechanism was promoted developing the new drugs treating rheumatic arthritis.
ABSTRACT
With IL-6R as target, a new compound 2460A was identified from fungus using HTS screening model. The taxonomics of the produced strain was confirmed to be Trichoderma hazianum rifai after sequencing analysis of rDNA-ITS (internal transcribed spacer). Results showed that this compound has a binding activity on IL-6R competed with IL-6, thus it is a new ligand of IL-6R originating from microbe. With MTT assay, the anti-tumor activities of 2460A were demonstrated on CM126 and HT-29 cell lines separately, the IC50 are 2.17 x 10(-5) mol x L(-1) and 1.8 x 10(-5) mol x L(-1) respectively. The compound affected lightly the HT-29 cell cycle at S phase. Studies for the anti-tumor activity of 2460A in vivo are in progress in our lab.