• Natural Product Sciences
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• v.21 no.4
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• pp.240-247
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• 2015

Viridicatol (1) has previously been isolated from the extract of the marine-derived fungus Penicillium sp. SF-5295. In the course of further biological evaluation of this quinolone alkaloid, anti-inflammatory effect of 1 in RAW264.7 and BV2 cells stimulated with lipopolysaccharide (LPS) was observed. In this study, our data indicated that 1 suppressed the expression of well-known pro-inflammatory mediators such as inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and consequently inhibited the production of iNOS-derived nitric oxide (NO) and COX-2-derived prostaglandin E2 ($PGE_2$) in LPS stimulated RAW264.7 and BV2 cells. Compound 1 also reduced mRNA expression of pro-inflammatory cytokines such as $interleukin-1{\beta}$ ($IL-1{\beta}$), interleukin-6 (IL-6), and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$). In the further evaluation of the mechanisms of these anti-inflammatory effects, 1 was shown to inhibit nuclear factor-kappa B ($NF-{\kappa}B$) pathway in LPS-stimulated RAW264.7 and BV2 cells. Compound 1 blocked the phosphorylation and degradation of inhibitor kappa B $(I{\kappa}B)-{\alpha}$ in the cytoplasm, and suppressed the translocation of $NF-{\kappa}B$ p65 and p50 heterodimer in nucleus. In addition, viridicatol (1) attenuated the DNA-binding activity of $NF-{\kappa}B$ in LPS-stimulated RAW264.7 and BV2 cells.

• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1206-1211
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• 2013

The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory fungal metabolites, the organic extracts of several fungal species isolated from marine environments were found to exhibit significant inhibitory effects, and the bioassay-guided investigation of these extracts resulted in the isolation of fructigenine A (1), cyclopenol (2), echinulin (3), flavoglaucin (4), and viridicatol (5). The structures of these compounds were determined mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 10.7, 30.0, 29.4, 13.4, and 64.0 ${\mu}M$, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compounds 1 and 5 suggested that compound 1 inhibited PTP1B activity in a noncompetitive manner, whereas compound 5 inhibited PTP1B activity in a competitive manner.