benzofurans and 6-6--bieckol

Brown algae have been used for their nutritional value as well as a source of bioactive compounds with antioxidant, anti-inflammatory, antimicrobial and anti-obesity effects. Obesity is an important condition implicated in various diseases, including diabetes, hypertension, dyslipidemia and coronary heart disease. However, anti-obesity effects of Eisenia bicyclis remain unknown.. We investigated the anti-obesity effects of 6,6'-bieckol, 6,8'-bieckol, 8,8'-bieckol, dieckol and phlorofucofuroeckol A isolated from E. bicyclis. Anti-obesity activity was evaluated by examining the inhibition of differentiation of 3T3-L1 adipocytes and the expression of peroxisome proliferator-activated receptor γ (PPARγ), CCATT/enhancer-binding protein α (C/EBPα) and sterol regulatory element binding protein-1c (SREBP-1c) at the mRNA and protein level. Differentiated 3T3-L1 cells were treated with the purified phlorotannins at concentrations of 10, 25 and 50 µg mL(-1) for 8 days. The results indicated that the purified phlorotannins suppressed the differentiation of 3T3-L1 adipocytes in a dose-dependent manner, without toxic effects. Among the five compounds, 6,6'-bieckol markedly decreased lipid accumulation and expression levels of PPARγ, C/EBPα, SREBP-1c (mRNA and protein), and fatty acid synthase and acyl-coA carboxylase (mRNA).. These findings suggest that E. bicyclis suppressed differentiation of 3T3-L1 adipocyte through downregulation of adipogenesis and lipogenesis.

Topics: 3T3-L1 Cells; Adipogenesis; Animals; Anti-Obesity Agents; Benzofurans; Carbon-Carbon Ligases; Cell Survival; Dioxins; Down-Regulation; Fatty Acid Synthase, Type I; Lipid Metabolism; Mice; Molecular Structure; Pacific Ocean; Phaeophyceae; PPAR gamma; Republic of Korea; Seaweed; Stereoisomerism

We investigated the effect of Ecklonia cava (E. cava)-derived dieckol on movement behavior and the expression of migration-related genes in MCF-7 human breast cancer cell. Phlorotannins (e.g., dieckol, 6,6'-biecko, and 2,7″-phloroglucinol-6,6'-bieckol) were purified from E. cava by using centrifugal partition chromatography. Among the phlorotannins, we found that dieckol inhibited breast cancer cell the most and was selected for further study. Radius™-well was used to assess cell migration, and dieckol (1-100 µM) was found to suppress breast cancer cell movement. Metastasis-related gene expressions were evaluated by RT-PCR and Western blot analysis. In addition, dieckol inhibited the expression of migration-related genes such as matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF). On the other hand, it stimulated the expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. These results suggest that dieckol exerts anti-breast cancer activity via the regulation of the expressions of metastasis-related genes, and this is the first report on the anti-breast cancer effect of dieckol.

Topics: Antineoplastic Agents; Benzofurans; Breast Neoplasms; Cell Movement; Cell Survival; Dioxanes; Dioxins; Drug Discovery; Female; Gene Expression Regulation, Neoplastic; Humans; Matrix Metalloproteinase 9; MCF-7 Cells; Neoplasm Proteins; Pacific Ocean; Phaeophyceae; Phloroglucinol; Republic of Korea; Seaweed; Tannins; Tissue Inhibitor of Metalloproteinase-1; Tissue Inhibitor of Metalloproteinase-2; Vascular Endothelial Growth Factor A

Chronic exposure of the skin to ultraviolet B (UVB) radiation induces oxidative stress, which plays a crucial role in the induction of skin cancer. In this study, the effect of dietary feeding and topical application of brown algae polyphenols on UVB radiation-induced skin carcinogenesis in SKH-1 mice was investigated. SKH-1 hairless mice were randomly divided into 9 groups, including control, UVB control and treatment groups. They were treated orally (0.1% and 0.5% with AIN-76 diet, w/w) and topically (3 and 6 mg/0.2 ml of vehicle) with brown algae polyphenols and irradiated with UVB for 26 weeks. Dietary feeding (0.1% and 0.5%) of brown algae polyphenols significantly reduced tumor multiplicity (45% and 56%) and tumor volume (54% and 65%), and topical administration (3 and 6 mg) significantly decreased tumor multiplicity (60% and 46%) and tumor volume (66% and 57%), respectively, per tumor-bearing mouse. Dietary feeding and topical administration of the polyphenols also inhibited tumor incidence by 6% and 21%, respectively, but the results were not significant. Dietary and topical administration of the polyphenols markedly inhibited cyclooxygenase-2 activity and cell proliferation. These observations show that brown algae polyphenols have an antiphotocarcinogenic effect which may be associated with the prevention of UVB-induced oxidative stress, inflammation, and cell proliferation in the skin.

Topics: Administration, Cutaneous; Administration, Oral; Animals; Benzofurans; Blotting, Western; Cell Proliferation; Cyclooxygenase 2; Dinoprostone; Dioxins; Epidermis; Female; Flavonoids; Gene Expression; Immunohistochemistry; Mice; Molecular Structure; Neoplasms, Radiation-Induced; Phaeophyceae; Phenols; Polyphenols; Proliferating Cell Nuclear Antigen; Random Allocation; Reverse Transcriptase Polymerase Chain Reaction; Skin; Skin Neoplasms; Ultraviolet Rays