Gukulenins A and B, cytotoxic tetraterpenoids from the marine sponge Phorbas gukulensis

Gukulenins A (1) and B (2), both having an unprecedented skeleton with a bis-tropolone moiety, were isolated from the Korean marine sponge Phorbas gukulensis. They exhibited significant cytotoxicity against human pharynx, stomach, colon, and renal cancer cell lines in the range 0.05-0.80 microM.

Scalarane sesterterpenes from a marine sponge of the genus Spongia and their FXR antagonistic activity

Three new scalarane-based sesterterpenes, 1- 3, were isolated from a marine sponge of the genus Spongia, and their chemical structures were elucidated by analysis of HRMS and 2-D NMR spectra. The isolated compounds 1 and 3 showed inhibition against the farnesoid X-activated receptor (FXR) with IC50 values of 2.4 and 24 microM, respectively. In particular, compound 3 directly inhibited the interaction between FXR and a coactivator peptide (SRC-1) as determined by surface plasmon resonance (SPR) spectroscopy.

Histopathologic changes of acellularized xenogenic carotid vascular grafts implanted in a pig-to-goat model

INTRODUCTION

The present study was designed to determine the in vivo patency and recellularization pattern of acellularized small-diameter xenogenic arterial grafts. We implanted acellularized porcine carotid arteries in bilateral carotid arteries of goats and microscopically analyzed the recellularization pattern of these grafts with the recipient's cells over time.

MATERIAL AND METHODS

Carotid arteries of pigs weighing 30-40 kg were harvested and decellularized with hypertonic saline followed by sodium dodecyl sulfate. Acellularized porcine carotid vascular xenografts (0.4-0.5 cm in diameter) were prepared into 4 cm-long segments and implanted bilaterally in the carotid arteries of 10 black-haired goats. The in vivo patency of the implanted acellularized xenogenic grafts was evaluated at regular intervals by color Doppler ultrasonography. The goats were sacrificed at predetermined intervals (1 week, 1 month, 3 months, 6 months, 12 months after implantation), two animals at each interval. Upon retrieval, visual inspections and histopathologic examinations of the grafts were performed. To identify smooth muscle cells and functioning endothelial cells, immunohistochemical staining for alpha-smooth muscle actin and von Willebrand factor were also performed.

RESULTS AND CONCLUSIONS

All experimental animals survived the observation period. Nineteen out of 20 implanted grafts showed patency with no thrombi. Microscopic analysis revealed that the grafts were completely covered with the hosts' endothelial cells, beginning from anastomotic sites. The grafts were gradually recellularized with recipients'cells including fibroblasts, myofibroblasts and smooth muscle cells. In conclusion, this study suggested that acellularized xenogenic vascular grafts can be a good alternative for the small-diameter vascular graft.

Two new monogalactosyl diacylglycerols from brown alga Sargassum thunbergii

Two new monogalactosyl diacylglycerols (MGDGs) along with two known glycolipids were isolated from the moderate polar fraction of the methanolic extract of the brown alga Sargassum thunbergii by using reversed silica flash chromatography. Two new MGDGs were identified as (2S)-1-O-(5Z,8Z,11Z,14Z,17Z-eicosapentaenoyl)-2-O-(9Z,12Z,15Z-octadecatrienoyl)-3-O-beta-D-galactopyranosyl-sn-glycerol (1) and (2S)-1-O-(9Z,12Z,15Z-octadecatrienoyl)-2-O-(6Z,9Z,12Z,15Z-octadecatetraenoyl)-3-O-beta-D-galactopyranosyl-sn-glycerol (2) by FAB tandem mass spectrometry, NMR techniques, and specific enzyme-catalyzed hydrolysis of the sn-1 fatty acyl linkage. The regiochemical attachment of the acyl chains in the glycerol moiety was established by 2D NMR correlations and confirmed by enzymatic hydrolysis.

Stylopine from Chelidonium majus inhibits LPS-induced inflammatory mediators in RAW 264.7 cells

Stylopine is a major component of the leaf of Chelidonium majus L. (Papaveraceae), which has been used for the removal of warts, papillomas and condylomas, as well as the treatment of liver disease, in oriental countries. Stylopine per se had no cytotoxic effect in unstimulated RAW 264.7 cells, but concentration-dependently reduced nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), and the IL-6 production and cyclooxygenase-2 (COX-2) activity caused by the LPS stimulation. The levels of inducible nitric oxide synthase (iNOS) and COX-2 protein expressions were markedly suppressed by stylopine in a concentration dependent manner. These results suggest that stylopine suppress the NO and PGE2 production in macrophages by inhibiting the iNOS and COX-2 expressions. These biological activities of stylopine may contribute to the anti-inflammatory activity of Chelidonium majus.

New sesterterpenes from the sponge Smenospongia sp

Five new sesterterpenes, three scalarane-type (1-3) and two linear furanosesterterpenes (4, 5), were isolated from the marine sponge Smenospongia sp. collected from Gagu-Do, Korea. The structures of the new compounds, which exhibited moderate cytotoxicity toward the human leukemia cell line K562, were determined from an analysis of spectroscopic data.

New sesterterpenes from the Antarctic sponge Suberites sp

Suberitenones C and D and suberiphenol, three new sesterterpenes of the suberitane class, were isolated from the sponge Suberites sp. collected from Antarctica. The structures of these compounds were determined on the basis of combined spectral and chemical analyses.

New sesterterpene sulfates from the sponge Darwinella australensis

Three new sesterterpene sulfates, halisulfates 8-10 (1-3), were isolated from the Australian sponge Darwinella australensis. The structures of these compounds were determined by combined spectroscopic methods. The stereochemistry of the decalin moiety was assigned on the basis of NMR interpretations. Halisulfates 9 and 10 inhibited cell division of sea urchin eggs in moderate concentration.

A new cyclic peptide from a marine-derived bacterium of the genus Nocardiopsis

A new cyclic tetrapeptide (1) was isolated from the culture broth of an actinomycete of the genus Nocardiopsis collected from the Pacific deep-sea sediment. The structure of this compound was determined to be cyclo-(L-isoleucyl-L-prolyl-L-leucyl-L-prolyl) on the basis of combined chemical and spectral methods.

New acetylenic acids from a sponge of the genus Stelletta

Three new acetylenic metabolites (1-3) were isolated from the sponge Stelletta sp. collected from Gagu-Do, Korea. On the basis of the results of combined spectroscopic analyses, the structures of these compounds were determined to be an acetylenic acid, its 2-methoxy analogue, and corresponding anhydride, respectively. The new compounds exhibited weak cytotoxicity against a human leukemia cell-line (K562).

Hydrazinocurcumin, a novel synthetic curcumin derivative, is a potent inhibitor of endothelial cell proliferation

Curcumin and some of its derivatives were known as in vivo inhibitors of angiogenesis. In present study, a novel curcumin derivative, named hydrazinocurcumin (HC) was synthesized and examined for its biological activities. HC potently inhibited the proliferation of bovine aortic endothelial cells (BAECs) at a nanomolar concentration (IC(50)=520 nM) without cytotoxicity. In vivo and in vitro angiogenesis experiments showed HC as a new candidate for anti-angiogenic agent.

Hydrazinocurcumin, a novel synthetic curcumin derivative, is a potent inhibitor of endothelial cell proliferation

Curcumin and some of its derivatives were known as in vivo inhibitors of angiogenesis. In present study, a novel curcumin derivative, named hydrazinocurcumin (HC) was synthesized and examined for its biological activities. HC potently inhibited the proliferation of bovine aortic endothelial cells (BAECs) at a nanomolar concentration (IC(50)=520 nM) without cytotoxicity. In vivo and in vitro angiogenesis experiments showed HC as a new candidate for anti-angiogenic agent.

New farnesylhydroquinone glycosides from the gorgonian Euplexaura anastomosans

Euplexides F (3) and G (4), novel farnesylhydroquinone glycosides, have been isolated as minor constituents of the gorgonian Euplexaura anastomosans. The structures of these compounds have been determined by combined spectroscopic methods. These compounds exhibited moderate cytotoxicity and inhibitory activity against PLA2.