Metachromin C was first isolated from the marine sponge and has been reported to possess potent cytotoxicity against leukemia cells. However, its antitumor activity and possible mechanisms in pancreatic cancer remain unclear. The effects of Metachromin C on cell viability were estimated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay.
View Article and Find Full Text PDFNaturally occurring 6-pentyl-2H-pyran-2-one and its synthetic analogues greatly inhibit the settlement of Amphibalanus amphitrite cyprids and the growth and biofilm formation of marine bacteria. To optimize the antifouling activities of pyrone derivatives, this study designed pyrone analogues by modifying functional groups, such as the benzyl group, cyclopentane, and halides, substituted on both sides of a pyrone. The antifouling effects of the synthesized pyrone derivatives were subsequently evaluated against five marine biofilm-forming bacteria, Loktanella hongkongensis, Staphylococcus cohnii, S.
View Article and Find Full Text PDFLung cancer is the leading cause of cancer-related death worldwide, and the survival rate of metastatic lung cancer is exceedingly low. Helminthostatchys Zeylanica (H. Zeylanica) is a Chinese herbal medicine renowned for its anti-inflammatory, immunomodulatory, and anti-cancer activities in various cellular and animal studies.
View Article and Find Full Text PDFBone loss is a major issue for patients with osteoporosis, arthritis, periodontitis, and bone metastasis; however, anti-resorption drugs used to treat bone loss have been linked to a variety of adverse effects. Helminthostachys zeylanica (L.) Hook, belonging to the family Ophioglossaceae, is commonly used in traditional Chinese medicine to treat inflammation and liver problems.
View Article and Find Full Text PDFSeven previously undescribed diterpenoids, tinocrisposides A-D (-) and borapetic acids A (), B (), and C (), together with 16 known compounds, were isolated from the stem of (Menispermaceae). The structures of the new isolates were elucidated by spectroscopic and chemical methods. The β-cell protective effect of the tested compounds was examined on insulin-secreting BRIN-BD11 cells under dexamethasone treatment.
View Article and Find Full Text PDFA specific α-oxoamine synthase () and an oxidoreductase () identified from marine sp. QWI-06 were involved in the decarboxylative condensation of l-tyrosine to lauroyl-CoA following the reduction of the ketone group to form vitroprocine-type compound . The intermediates and products were characterized through HR-MS and their MS/MS fragmentations.
View Article and Find Full Text PDFPhytochemicals that interrupt adipocyte lifecycle can provide anti-obesity effects. 1,2,3,4,6-penta-O-galloyl-d-glucose (PGG) is a tannin with two isomers that occurs widely in plants and exhibits various pharmacological activities. The aim of the investigation is to comprehensively examine effects of PGG isomer(s) on adipocyte lifecycle and diet-induced obesity.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
February 2022
Pyridoxal phosphate (PLP)-dependent α-oxoamine synthases are generally believed to be responsible for offloading and elongating polyketides or catalyzing the condensation of amino acids and acyl-CoA thioester substrates, such as serine into sphingolipids and cysteate into sulfonolipids. Previously, we discovered vitroprocines, which are tyrosine- and phenylalanine-polyketide derivatives, as potential new antibiotics from the genus Vibrio. Using bioinformatics analysis, we identified putative genes of PLP-dependent enzyme from marine Vibrio sp.
View Article and Find Full Text PDFBiofouling is a widespread phenomenon in oceans worldwide. With increasing human development and activities in open and coastal waters, and due to the environmental impact of AF organotins and copper-based paint, the demand for nontoxic antifouling (AF) paints is increasing. Various bioassays for antimicrobial activity, anti-biofilm formation and anti-barnacle settlement were established to evaluate the possibility of using marine natural products as AF agents.
View Article and Find Full Text PDFBy an ESI-LC/MS analytical method, a racemate 1 consisting of a pair of unprecedented phloroglucinol enantiomers with a 5/6/5/5/6 fused ring system, (-)-garcinielliptone HG [((-)-1a] and (+)-garcinielliptone HH [(+)-1b], was obtained from the isolates of a CHCl extract of Garcinia subelliptica (heartwood). The gross structure of 1 was elucidated by spectroscopic methods and X-ray single-crystal diffraction data. The absolute configurations of 1a and 1b were unequivocally assigned by analysis on the calculated and experimental circular dichroism spectra and X-ray single-crystal diffraction data.
View Article and Find Full Text PDFBackground: Dengue virus (DENV), a common and widely spread arbovirus, causes life-threatening diseases, such as dengue hemorrhagic fever or dengue shock syndrome. There is currently no effective therapeutic or preventive treatment for DENV infection.
Methods: Next-generation sequencing analysis revealed that prostasin expression was decreased upon DENV infection.
Hepatitis C virus (HCV) chronically infects 2-3% people of the global population, which leads to liver cirrhosis and hepatocellular carcinoma. Drug resistance remains a serious problem that limits the effectiveness of US Food and Drug Administration (FDA)-approved direct-acting antiviral (DAA) drugs against HCV proteins. The objective of our study was to discover new antivirals from natural products to supplement current therapeutics.
View Article and Find Full Text PDFXylaria nigripes, also known as Wu Ling Shen, is popular for treating insomnia and trauma in traditional Chinese medicine. This study aimed to examine the anti-inflammatory activity and bioactive constituents of cultivated X. nigripes fruiting bodies in lipopolysaccharide (LPS)-treated RAW 264.
View Article and Find Full Text PDFNeointimal hyperplasia (or restenosis) is primarily attributed to excessive proliferation and migration of vascular smooth muscle cells (VSMCs). In this study, we investigated the inhibitory effects and mechanisms of ugonin J on VSMC proliferation and migration as well as neointimal formation. Cell viability and the cell-cycle distribution were, respectively, analyzed using an MTT assay and flow cytometry.
View Article and Find Full Text PDFontinuing chemical investigation of the ethyl acetate (EtOAc) extract of a reef soft coral , which was cultured in a tank, afforded four new steroids with methyl ester groups, sinubrasones A-D (1-4) for the first time. In particular, 1 possesses a β-D-xylopyranose. The structures of the new compounds were elucidated on the basis of spectroscopic analyses.
View Article and Find Full Text PDFObjective: Pancreatic cancer is one of the most lethal types of cancer with a 5-year survival rate of ~5%. Histone deacetylases (HDACs) participate in many cellular processes, including carcinogenesis, and pharmacological inhibition of HDACs has emerged as a potential therapeutic strategy. In this study, we explored antitumor activity of the novel HDAC inhibitor AR-42 in pancreatic cancer.
View Article and Find Full Text PDFWe previously reported that the soft coral-derived bioactive substance, sinuleptolide, can inhibit the proliferation of oral cancer cells in association with oxidative stress. The functional role of oxidative stress in the cell-killing effect of sinuleptolide on oral cancer cells was not investigated as yet. To address this question, we introduced the reactive oxygen species (ROS) scavenger (-acetylcysteine [NAC]) in a pretreatment to evaluate the sinuleptolide-induced changes to cell viability, morphology, intracellular ROS, mitochondrial superoxide, apoptosis, and DNA damage of oral cancer cells (Ca9-22).
View Article and Find Full Text PDFFive new isoprenoids, 3,4,8,16-tetra--lobocrasol (), 1,15β-epoxy-deoxysarcophine (), 3,4-dihydro-4α,7β,8α-trihydroxy-Δ²-sarcophine (3), -sarcophyolide E (4), and 16-deacetyl- halicrasterol B (5) and ten known compounds 6‒, were characterized from the marine soft coral , collected off Taitung coastline. Their structures were defined by analyzing spectra data, especially 2D NMR and electronic circular dichroism (ECD). The structure of the known compound lobocrasol () was revised.
View Article and Find Full Text PDFContinuing study of the ethyl acetate (EtOAc) extract of the cultured soft coral Sinularia brassica afforded five new withanolides, sinubrasolides H-L (1-5). The structures of the new compounds were elucidated on the basis of spectroscopic analysis. The cytotoxicities of new compounds 1-5 and a known compound sinubrasolide A (6) against the proliferation of a limited panel of cancer cell lines were assayed.
View Article and Find Full Text PDFSoft corals-derived natural product, sinularin, was antiproliferative against some cancers but its effect and detailed mechanism on oral cancer cells remain unclear. The subject of this study is to examine the antioral cancer effects and underlying detailed mechanisms in terms of cell viability, oxidative stress, cell cycle analysis, and apoptosis analyses. In MTS assay, sinularin dose-responsively decreased cell viability of three oral cancer cells (Ca9-22, HSC-3, and CAL 27) but only little damage to oral normal cells (HGF-1).
View Article and Find Full Text PDFCyclooxygenase-2 (COX-2) is one of the important mediators of inflammation in response to viral infection, and it contributes to viral replication, for example, cytomegalovirus or hepatitis C virus replication. The role of COX-2 in dengue virus (DENV) replication remains unclear. In the present study, we observed an increased level of COX-2 in patients with dengue fever compared with healthy donors.
View Article and Find Full Text PDFThe NOD-like receptor pyrin domain 3 (NLRP3) inflammasome contains Nod-like receptors, a subclass of pattern recognition receptors, suggesting that this complex has a prominent role in host defenses. Various structurally diverse stimulators activate the NLRP3 inflammasome through different signaling pathways. We previously reported that ugonin U (UgU), a natural flavonoid isolated from Helminthostachys zeylanica (L) Hook, directly stimulates phospholipase C (PLC) and triggers superoxide release in human neutrophils.
View Article and Find Full Text PDFPhytochemical investigation of the ethanolic extract of Grangea maderaspatana led to isolation of gramaderins A-D, together with thirteen known compounds. All isolates were assayed for their anti-inflammatory activities. Consequently, 5,7-dihydroxy-3,6,3',4',5'-pentamethoxyflavone and 5,3'-dihydroxy-3,6,7,4',5'-pentamethoxyflavone showed significant bioactivities by inhibiting superoxide anion generation.
View Article and Find Full Text PDFTwo new compounds, 4,10-dihydroxy-11-methyl-dodec-2-en-1,4-olide () (butyrolactone-type) and cyclo-(4--6-dihydroxy-proline-D-leucine) () (diketopiperazine-type), as well as one known 4,10-dihydroxy-10-methyl-dodec-2-en-1,4-olide () and three known diketopiperazines, cyclo-(L-proline-L-leucine) (), cyclo-(4--hydroxy-L-proline-L-leucine) (), and cyclo-(4--hydroxy-L-proline-L-phenylalanine) (), were isolated from the ethyl acetate extracts of GT and C-03. Compounds , and exhibited a significant reduction effect on dengue virus type 2 replication with EC values of 21.2, 16.
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