BACKGROUND Saponins have been shown to possess many pharmacological properties, including altered fat metabolism. The black sea cucumber, Holothuria leucospilota, is a marine animal that contains a specialized organ called a Cuvierian tubule that produces and secrete the bioactive saponins into the tubules and body wall. Therefore, the aims of this study are to investigate the anti‐obesity effect of saponins extracted from body wall and Cuvierian tubules of H. leucospilota. RESULTS The butanol extracts of H. leucospilota body wall and Cuvierian tubules containing high amounts of saponins significantly reduced fat deposition and triglyceride levels in Caenorhabditis elegans fed with 50 mmol L−1 glucose. Moreover, the saponin‐enriched extracts of H. leucospilota significantly restored the lifespan of 2% glucose‐fed worms (18.71%). Green fluorescence protein‐labeled sbp‐1 gene expression and nuclear translocation of daf‐16 were also significantly decreased in H. leucospilota treatment. The saponin‐enriched extracts downregulated the messenger RNA expressions of genes involved in fat storage and metabolism, including sbp‐1, cebp, and daf‐16 but upregulated the expression of nhr‐49 gene. CONCLUSION Our results suggest that H. leucospilota‐derived saponins may mediate the reduction of glucose‐induced fat accumulation through sbp‐1, cebp, daf‐16 and nhr‐9 pathways. Therefore, the H. leucospilota extracts could be used as nutraceuticals for anti‐obesity prevention. © 2019 Society of Chemical Industry

Extracts from a sea cucumber, Holothuria scabra, have been shown to exhibit various pharmacological properties including anti-oxidation, anti-aging, anti-cancer, and anti-neurodegeneration. Furthermore, certain purified compounds from H. scabra displayed neuroprotective effects against Parkinson’s and Alzheimer’s diseases. Therefore, in the present study, we further examined the anti-aging activity of purified H. scabra compounds in a Caenorhabditis elegans model. Five compounds were isolated from ethyl acetate and butanol fractions of the body wall of H. scabra and characterized as diterpene glycosides (holothuria A and B), palmitic acid, bis (2-ethylhexyl) phthalate (DEHP), and 2-butoxytetrahydrofuran (2-BTHF). Longevity assays revealed that 2-BTHF and palmitic acid could significantly extend lifespan of wild type C. elegans. Moreover, 2-BTHF and palmitic acid were able to enhance resistance to paraquat-induced oxidative stress and thermal stress. By testing the compounds’ effects on longevity pathways, it was shown that 2-BTHF and palmitic acid could not extend lifespans of daf-16, age-1, sir-2.1, jnk-1, and skn-1 mutant worms, indicating that these compounds exerted their actions through these genes in extending the lifespan of C. elegans. These compounds induced DAF-16::GFP nuclear translocation and upregulated the expressions of daf-16, hsp-16.2, sod-3 mRNA and SOD-3::GFP. Moreover, they also elevated protein and mRNA expressions of GST-4, which is a downstream target of the SKN-1 transcription factor. Taken together, the study demonstrated the anti-aging activities of 2-BTHF and palmitic acid from H. scabra were mediated via DAF-16/FOXO insulin/IGF and SKN-1/NRF2 signaling pathways.

This study aimed to evaluate the bioactivity and phytochemical investigation in red algae Halymenia durvillei. The polarity based solvent partition (hexane, ethyl acetate, butanol and water) of H. durvillei ethanolic crude were used for characterization. The present results of the ethyl acetate extract of red alga H. durvillei generated a 3-(hydroxyacetyl)indole (1), indole-3-carboxylic acid (2) as well as two fatty acids viz. palmitic acid (3) and α-linoleic acid (4). The viability against lung cancer cells of compounds 1 and 2 showed moderate activities against the A549 cell line with inhibition percentages of 12.97% and 25.81%, respectively. Analysis of the dose response of C. elegans anti-aging assay indicated that the survival rate of compound 1 was 12.62% while it was 11.04% for compound 2. Furthermore, H. durvillei isolation was used as an antioxidant, anti-cancer cell and anti-aging resource.