Extraction Of Biological Activity Of Microorganisms In Fermented 04-9179 Study On Isolation And Structure Identification And Raised Cla-1 Activities

Coronary heart disease is one of the most common diseases that damage human health, while atherosclerosis is the key factor for the disease. Although the mechanism of AS formation is not totally clear till now, recent researches showed that the elevated level of HDL-C is very important for protecting against atherogenesis. The scavenger receptor class B type I (SR-BI) was reported as the first molecularly well-defined and functionally active cell-surface HDL receptor (HDL-R) which can mediate the selective uptake of HDL-CE by cells through taking part in reverse cholesterol transport (RCT). The establishment of high-throughput screening model of SR-BI up-regulators has been reported and new compounds which can elevate SR-BI expression level might be good candidates for the leading compounds of new anti-atherosclerosis drugs. A large scale high-throughput screening work on the second metabolites of microorganisms (fermentation broth and crude extracts) has been launched using our established screening model to search for up-regulators of human HDL receptor CLA-1. Several positive strains have been found which can produce active metabolites in up-regulating CLA-1 expression.Within this work, we tried to identify the active compound(s) produced by the positive strains 04-9179. After cultivating the strain 04-9179, its fermentation broth was isolated and one positive compound 9179A and two other positive components 9179B, 9179C were purified. The structure of compound 9179A was identified and the results showed that 9179A is an known compound named 7-[4-(Dimethylamino)phenyl]-N-hydroxy-4,6-dimethyl-7-oxo-2,4-heptadienamide. The effect of 9179A on up-regualting the expression of human HDL receptor CLA-1 on HepG2 cells was confirmed on mRNA level and protein level by semiquantitative RT-PCR and Western blot. Furthermore, flow cytometry assay also showed that the DiI-HDL binding and uptake by HepG2 cells were increased after being treated with 9179A. 9179A has also been subjected to PPAR agonist screening model and gave a positive result. This may imply that PPAR is one of the factors that are involved in the process of CLA-1 expression regulated by 9179A.