Structural analysis of epolactaene derivatives as DNA polymerase inhibitors and anti-inflammatory compounds
- Authors: Yoshiyuki Mizushina, Kouji Kuramochi, Hiroshi Ikawa, Isoko Kuriyama, Noriko Shimazaki, Masaharu Takemura, Masahiko Oshige, Hiromi Yoshida, Osamu Koiwai, Fumio Sugawara, Susumu Kobayashi, Kengo Sakaguchi
Published on: 01 May 2005
- Pages: 785-793
Epolactaene (compound 1), a neuritogenic compound found in human neuroblastoma cells, was found to show anti-inflammatory activity in vivo in this study. DNA polymerases and DNA topoisomerase II (topo II) were some of the major molecular targets of compound 1. Since the agent seems to be a potential pharmaceutical medicine, we synthesized derivatives chemically and obtained seven compounds, 1 to 7 to screen clinically more efficient epolactaene derivatives. A comparison of its structural derivatives revealed that the long alkyl side chain seemed to have an important role in the inhibitory effect. Notably, C18-alkyl chain conjugated epolactaene (compound 5) was the strongest inhibitor of DNA polymerase α, β, λ (pol α, β, λ) and topo II, with IC50 values of 13, 135, 4.4 and 5 µM, respectively, and 500 µg of compound 5 caused a marked reduction in TPA (12-O-tetradecanoylphorbol-13-acetate)-induced inflammation (inhibitory effect, 65.0%). Compound 5 did not influence the activities of plant or prokaryotic DNA polymerases, or of other DNA metabolic enzymes such as telomerase, RNA polymerase and deoxyribonuclease I. Based on these results, the relationship among the three-dimensional structure of epolactaene derivatives and the inhibition of poly-merases and topo II, and anti-inflammation is discussed.