Dykellic acid inhibits phorbol myristate acetate-induced matrix metalloproteinase-9 expression by inhibiting nuclear factor kappa B transcriptional activity.

Proteolytic degradation of the extracellular matrix and tumor metastasis correlate with expression of endopeptidases known as matrix metalloproteinases (MMPs). Expression of MMPs is regulated by cytokines and signal transduction pathways, including those activated by phorbol myristate acetate. We found that dykellic acid, a fungal metabolite, significantly inhibits the phorbol myristate acetate-induced increase in MMP-9 expression and activity. These effects of dykellic acid are time- and dose-dependent, and correlate with decreased MMP-9 promoter activity and mRNA expression. Whereas this compound does not affect DNA binding activity of nuclear factor kappa B (NF kappa B), dykellic acid does inhibit transactivation of NF kappa B. These data demonstrate a role for NF kappa B in the regulation of MMP-9 expression and the ability of dykellic acid to suppress this action of NF kappa B.

Tungtungmadic acid, a novel antioxidant, from Salicornia herbacea.

Tungtungmadic acid (3-caffeoyl-4-dihydrocaffeoyl quinic acid) is a new chlorogenic acid derivative that was isolated from the Salicornia herbacea. The structure of tungtungmadic acid was determined using chemical and spectral analysis. The antioxidant activity of tungtungmadic acid was evaluated using various antioxidant assays, including free radical scavenging, lipid peroxidation and hydroxyl radical-induced DNA strand breaks assays. Tungtungmadic acid (IC50 = 5.1 microM and 9.3 microM) was found to have higher antioxidant activity in the DPPH scavenging assay as well as in the iron-induced liver microsomal lipid peroxidation system. In addition, the tungtungmadic acid was also effective in protecting the plasmid DNA against strand breakage induced by hydroxyl radicals.

The coffee diterpene kahweol suppress the inducible nitric oxide synthase expression in macrophages.

Excessive nitric oxide production by inducible nitric oxide synthase (iNOS) in stimulated inflammatory cells is thought to be a causative factor of cellular injury in cases of inflammation. In recent studies, it has been shown that kahweol, coffee-specific diterpene, exhibit chemoprotective effects. In this study, we investigated the effects of kahweol on the production of and the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. The nitrite production induced by LPS was markedly reduced in a dose-dependent manner. In addition, kahweol suppressed the expression of iNOS protein and iNOS mRNA. Since iNOS transcription has been shown to be under the control of the transcription factor, NF-kappaB, the effects of kahweol on NF-kappaB activation were examined. Transient transfection experiments showed that kahweol inhibited NF-kappaB-dependent transcriptional activity. Moreover, electrophoretic mobility shift assay experiments indicated that kahweol blocked the LPS-induced activation of NF-kappaB. The results of these studies suggest that the suppression of the transcriptional activation of iNOS by kahweol might be mediated through the inhibition of NF-kappaB activation. Taken together, the results of our study provide evidence that kahweol possess an anti-inflammatory potential, which constitutes a previously unrecognized biologic activity, and which may provide new insights into the inflammatory process.

Dykellic acid inhibits cell migration and tube formation by RhoA-GTP expression.

Dykellic acid, a novel factor initially identified from the culture broth of Westerdykella multispora F50733, has been shown to inhibit matrix metalloprotease 9 activity, caspase-3 activity, B cell proliferation and LPS-induced IgM production, suggesting that this factor may have anti-cancer effects. In an effort to further address the possible anti-tumoral effects of dykellic acid, we used wound healing, invasion and RhoA-GTP assays to examine the effects of dykellic acid on cell migration, invasion and angiogenesis. Our results revealed that dykellic acid dose-dependently inhibits B16 cell migration and motility, and inhibits HUVEC tube formation. Western blot analysis of the active form of RhoA (RhoA-GTP) showed that dykellic acid treatment decreased the levels of RhoA-GTP. These findings collectively suggest that dykellic acid may have both anti-metastatic and anti-angiogenic acitivites, and provides the first evidence for the involvement of RhoA in dykellic acid-induced effects.

Gelastatins and their hydroxamates as dual functional inhibitors for TNF-alpha converting enzyme and matrix metalloproteinases: synthesis, biological evaluation, and mechanism studies.

The hydroxamic acid analogues (2) of the natural product gelastatins (1) were prepared by 1 step conversion reaction. The synthetic analogues (2) showed potent enzymatic inhibitory activities against MMP-2, MMP-9, and TACE IC50's of 6, 23, and 28 nM, respectively. In addition, 2 were able to inhibit TNF-alpha production effectively in mice as well as in a macrophage cell line, RAW 264.7. The protective effect of 2 also was examined on LPS-induced acute septic shock model. The mechanism of TNF-alpha inhibition was examined by RT-PCR and Western blot analyses. The relation of TACE and alpha-secretase was examined using cellular alpha-secretase assays on IMR-32 and SH-SY5Y cell lines. The docking mode of 2 with the catalytic domain of TACE was illustrated to analyze the binding mode for the further analogue design.

Cytotoxic triterpenoids from the fruits of Zizyphus jujuba.

The following eleven triterpenoic acids were isolated from the fruits of Zizyphus jujuba (Rhamnaceae): colubrinic acid, alphitolic acid, 3-O-cis-p-coumaroylalphitolic acid (3), 3-O-trans-p-coumaroylalphitolic acid (4), 3-O-cis-p-coumaroylmaslinic acid, 3-O-trans-p-coumaroylmaslinic acid, betulinic acid (7), oleanolic acid, betulonic acid (9), oleanonic acid and zizyberenalic acid. The in vitro cytotoxicities of the triterpenoic acids against K562, B16(F-10), SK-MEL-2, PC-3, LOX-IMVI, and A549 tumor cell lines were investigated by the sulforhodamin B (SRB) method. Among these compounds, the lupane-type triterpenes, such as compounds 3, 4, 7, and 9, showed high cytotoxic activities. In particular, the cytotoxic activities of 3-O-p-coumaroylalphitolic acids (compounds 3 and 4) were better than those of non-coumaroic triterpenenoids (compounds 7 and 9). These results suggest that the coumaroyl moiety at the C-3 position of the lupane-type triterpene may play an important role in enhancing cytotoxic activity.

Dykellic acid inhibits drug-induced caspase-3-like protease activation.

Dykellic acid is a novel microbial metabolite isolated from the broth of Westerdykella multispora F50733. Investigations on the molecular function of dykellic acid revealed that this compound partially inhibits calcium influx, resulting in a decrease in Ca(2+)-dependent endonuclease activation and DNA fragmentation induced by camptothecin. In our experiments, active caspase-3-like protease cleavage of procaspase-3, PARP, and cytosolic cytochrome c was inhibited by dykellic acid in a concentration-dependent manner when the apoptosis was induced by camptothecin as well as doxorubicin. We confirmed that dykellic acid did not bind to camptothecin using surface plasmon resonance analysis. These results suggest that dykellic acid inhibits drug-induced apoptosis via a caspase-3-like protease-suppressing mechanism. Our data provide important information on the mechanism of action of dykellic acid and indicate that this compound may be employed in the treatment of specific caspase-3-like protease-mediated diseases.

New guaianolides from leaves and stems of Chrysanthemum boreale.

The 8-acetoxy-2-methoxy-10-hydroxy-3,11(13)-guaiaden-12,6-olide 1 and 8,10-diacetoxy-2-methoxy-3,11(13)-guaiadiene-12,6-olide 2 were isolated from Chrysanthemum boreale Makino. Compound 1 inhibited the etoposide-induced apoptosis in U 937 cells with an IC50 value 8.6 microg/mL.

Paenibacillus chinjuensis sp. nov., a novel exopolysaccharide-producing bacterium.

A novel exopolysaccharide-producing bacterium (WN9T) was isolated from Chinju, Korea, and was identified as a member of the genus Paenibacillus on the basis of phenotypic characteristics and phylogenetic inference based on 16S rDNA sequence. This organism is a facultatively anaerobic, endospore-forming rod. The diamino acid found in the peptidoglycan is meso-diaminopimelic acid. The predominant menaquinone is MK-7. The major cellular fatty acid is anteiso-C15:0. The G+C content is 53 mol%. The phylogenetic tree shows that strain WN9T falls within the radiation of a cluster comprising the Paenibacillus species. The levels of 16S rDNA similarity between strain WN9T and the type strains of validly described Paenibacillus species are 92.1-95.8%. Strain WN9T is clearly distinguishable from some phylogenetically related Paenibacillus species on the basis of DNA-DNA relatedness data and phenotypic characters. Therefore, on the basis of these data, a novel species of the genus Paenibacillus, Paenibacillus chinjuensis sp. nov., is proposed. The type strain is strain WN9T (= KCTC 8951PT = JCM 10939T).

Eucosterol oligoglycosides isolated from Scilla scilloides and their anti-tumor activity.

Two new eucosterol oligoglycosides, 15-deoxo-30-hydroxyeucosterol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[(beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside (scillanoside L-1, 1) and 3beta,31-dihydroxy-17alpha,23-epoxy-5alpha-lanost-8-en-23,26-olactone 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside (scillanoside L-2, 2), were isolated from the bulbs of Scilla scilloides, together with four that were known (3-6), have been isolated from the bulbs of Scilla scilloides. The structures of the new compounds were determined on the basis of spectroscopic and chromatographic methods, and some chemical transformations were discussed. Amongst the isolated compounds, 3 showed the most significant cytotoxicity against tumor cells tested several types with ED(50) value of 1.53-3.06 nM. In vivo experiments, 3 apparently increased the life span of mice bearing Sarcoma 180 tumor cell with T/C value of 239% at dose of 3 mg/kg.

Halomonas alimentaria sp. nov., isolated from jeotgal, a traditional Korean fermented seafood.

A gram-negative, moderately halophilic bacterial strain, YKJ-16T, which was isolated from jeotgal, a traditional Korean food, was considered to be a member of the genus Halomonas. Cells of strain YKJ-16T are non-motile and cocci or short rods, unlike most Halomonas species. However, chemotaxonomic and phylogenetic analyses demonstrated that strain YKJ-16T belongs to the genus Halomonas. The predominant isoprenoid quinone is ubiquinone-9. The major fatty acids are C18.1omega7c, C16:0, C19:0 cyclo omega8c and C16:1omega7c and/or iso C15:0 20H. The phylogenetic tree showed that strain YKJ-16T forms a distinct evolutionary lineage within the radiation comprising Halomonas species and forms a coherent cluster with Halomonas halodenitrificans, Halomonas cupida and Halomonas pacifica. Levels of 16S rDNA similarity between strain YKJ-16T and the type strains of other Halomonas species are 93.0-96.3%. Levels of DNA-DNA relatedness indicate a taxonomic status of strain YKJ-16T as a species different from the three species that form the coherent cluster mentioned above. Morphologically, strain YKJ-16T is also clearly differentiated from the type strains of H. cupida and H. pacifica. Accordingly, on the basis of the phenotypic characteristics, 16S rDNA sequence analysis and DNA relatedness data, strain YKJ-16T should be placed in the genus Halomonas as a novel species. The name Halomonas alimentaria sp. nov. is proposed with strain YKJ-16T (= KCCM 41042T = JCM 10888T) as the type strain.

Enhancement of tyrosinase inhibition of the extract of Veratrum patulum using cellulase.

Inhibitors of melanin biosynthesis were screened by using three different methods. The extract of Veratrum patulum contains hydroxystilbene compounds that are potent tyrosinase inhibitors. We evaluated the enzyme inhibitory property on the mushroom tyrosinase of hydroxystilbene compounds including resveratrol, oxyresveratrol, and their analogs. Biotransformation using cellulase of the whole extract brought about an increase in the inhibitory activity of the products on mushroom tyrosinase. The enhancement of tyrosinase inhibition is supposed to increase the concentration of aglycon, which has superior inhibitory activity to its glycoside. Eventually, melanin biosynthesis was inhibited by the enhanced tyrosinase inhibitory activity of the extract. This result indicated that deglycosylation of stilbene compounds has exerted more effective inhibition on the enzyme than that of the unprocessed plant extract.

Biological effects of G1 phase arrest compound, sesquicillin, in human breast cancer cell lines.

Sesquicillin, isolated from fungal fermentation broth, strongly induced G1 phase arrest in human breast cancer cells. During G1 phase arrest, the expression level of cyclin D1, cyclin A, and cyclin E was decreased, and the expression of CDK (cyclin-dependent-kinase) inhibitor, protein p21(Waf1/Cip1), was increased in a time-dependent manner in a breast cancer cell MCF-7. Interestingly, the G1 phase arrest induced by sesquicillin also occurred independently of the tumor suppressor protein, p53. Sesquicillin inhibits the proliferation of MCF-7 via G1 phase arrest in association with the induction of CDK inhibitor protein, p21(Waf1/Cip1), and the reduction of G1 phase related-cyclin proteins.