Shang-Kwei Wang

Antiviral and Anti-inflammatory Metabolites from the Soft Coral Sinularia capillosa

Chemical investigations of the soft coral Sinularia capillosa resulted in the isolation of one new tetraprenylbenzoquinone, capilloquinone (1), two new furanobenzosesquiterpenoids, capillobenzopyranol (2) and capillobenzofuranol (3), one new furanosesquiterpenoid, capillofuranocarboxylate (4), and five previously characterized metabolites, comprising (E)-5-(2,6-dimethylocta-5,7-dienyl)furan-3-carboxylic acid (5), 2-[(2E,6E)-3,7-dimethyl-8-(4-methylfuran-2-yl)octa-2,6-dienyl]-5-methylcyclohexa-2,5-diene-1,4-dione (6), 2-[(2E,6E)-3,7-dimethyl-8-(4-methylfuran-2-yl)octa-2,6-dienyl]-5-methylbenzene-1,4-diol (7), (-)-loliolide (8), and 3,4,11-trimethyl-7-methylenebicyclo[6.3.0]undec-2-en-11alpha-ol (9). The structures of 1-4 were elucidated through extensive spectroscopic analysis. The cytotoxicity, anti-HCMV (human cytomegalovirus) activity, antibacterial activity, and anti-inflammatory effects of 1-9 were evaluated in vitro.

Bioactive norditerpenoids from the soft coral Sinularia gyrosa.

Chemical investigations of the soft coral Sinularia gyrosa resulted in the isolation of six new norcembranolides, gyrosanolides A-F (1-6), a new norcembrane, gyrosanin A (7), and 11 known norditerpenoids 8-18. The structures of the isolated compounds were elucidated through extensive spectroscopic data and by comparison with reported data in the literature. Compounds 1-3, 7-9, 12, and 13 at concentration of 10microM did not inhibit the COX-2 protein expression, but significantly reduced the levels of the iNOS protein (55.2+/-14.6%, 18.6+/-6.7%, 10.6+/-4.6%, 66.9+/-5.2%, 10.2+/-5.1%, 17.4+/-7.2%, 47.2+/-11.9%, and 56.3+/-5.1%, respectively) by LPS stimulation. Compound 8 showed significant antiviral activity against HCMV (human cytomegalovirus) cells with an IC(50) of 1.9microg/mL.

Cembranoids from the octocoral Sarcophyton ehrenbergi.

Chemical investigation of the octocoral Sarcophyton ehrenbergi led to the isolation of six new cembranoids, (+)-12-carboxy-11Z-sarcophytoxide (1), (+)-12-methoxycarbonyl-11Z-sarcophine (3), ehrenberoxides A-C (4-6), and lobophynin C (2), along with two known compounds, (+)-sarcophytoxide (7) and (+)-sarcophine (8). The structures of these isolated metabolites were elucidated through extensive spectroscopic analyses, while the relative configuration of 1 was confirmed by X-ray diffraction analyses. The chemical evidence combined with spectroscopic and physical data suggested that the locations of the epoxide and the methyl carboxylate for lobophynin C should be exchanged. Moreover, metabolites 1-6 were evaluated in vitro for their cytotoxicity against selected cancer and normal cells lines, antiviral activity against human cytomegalovirus, and antibacterial activity against Salmonella enteritidis.

A novel cytotoxic norditerpenoid from the Formosan soft coral Sinularia inelegans

Abstract A novel cytotoxic norditerpenoid, ineleganolide (1), has been isolated from the soft coral Sinularia inelegans. The structure of 1 (novel carbon skeleton) was determined by spectral and X-ray diffraction analysis.

Human cytomegalovirus UL76 induces chromosome aberrations

BackgroundHuman cytomegalovirus (HCMV) is known to induce chromosome aberrations in infected cells, which can lead to congenital abnormalities in infected fetuses. HCMV UL76 belongs to a conserved protein family from herpesviruses. Some reported roles among UL76 family members include involvement in virulence determination, lytic replication, reactivation of latent virus, modulation of gene expression, induction of apoptosis, and perturbation of cell cycle progression, as well as potential nuclease activity. Previously, we have shown that stable expression of UL76 inhibits HCMV replication in glioblastoma cells.MethodsTo examine chromosomal integrity and the DNA damage signal γ-H2AX in cells constitutively expressing UL76, immunofluorescent cell staining and Western blotting were performed. The comet assay was employed to assess DNA breaks in cells transiently expressing UL76.ResultsWe report that stably transfected cells expressing UL76 developed chromosome aberrations including micronuclei and misaligned chromosomes, lagging and bridging. In mitotic cells expressing UL76, aberrant spindles were increased compared to control cells. However, cells with supernumerary centrosomes were marginally increased in UL76-expressing cells relative to control cells. We further demonstrated that UL76-expressing cells activated the DNA damage signal γ-H2AX and caused foci formation in nuclei. In addition, the number of cells with DNA breaks increased in proportion to UL76 protein levels.ConclusionOur findings suggest that the virus-associated protein UL76 induces DNA damage and the accumulation of chromosome aberrations.

Anti-inflammatory cembranolides from the soft coral Lobophytum durum.

Chemical investigation of the soft coral Lobophytum durum resulted in the isolation of seven new cembranolides, durumolides F-L (1-7), as well as one previously characterized cembranolides, sinularolide D (8). The molecular structures of these isolated metabolites were determined mainly through NMR techniques and HRESIMS analysis. Moreover, the absolute configurations of 1 and 5 were established by application of modified Moshers method. The antibacterial activities, anti-inflammatory effects, and anti-HCMV (Human cytomegalovirus) endonuclease activity of metabolites 1-8 were also evaluated in vitro. Anti-inflammatory activity of metabolites 1 and 6 (10 microM) significantly reduced the levels of the iNOS protein to 0.8+/-0.6% and 5.7+/-2.2%, respectively, and COX-2 protein to 47.8+/-9.0% and 71.6+/-5.8%, respectively. Metabolites 1-8 (100 microg/disk) exhibited weak antibacterial activity against Salmonella enteritidis.

Antiviral and anti-inflammatory diterpenoids from the soft coral Sinularia gyrosa.

Chemical investigation of the soft coral Sinularia gyrosa led to the purification of three new diterpenoids, designated as gyrosanols A-C (1-3). The structures of 1-3 were elucidated through extensive spectroscopic analyses. Compounds 1 and 2 exhibited antiviral activity against HCMV with IC(50)s of 2.6 and 3.7 microM, respectively. In addition, compounds 1 and 2 showed significant anti-inflammatory activity by reducing the levels of the COX-2 protein (19.6 + or - 3.9% and 29.1 + or - 9.6%, respectively) in RAW 264.7 macrophages.

Human Cytomegalovirus UL76 Encodes a Novel Virion-Associated Protein That Is Able To Inhibit Viral Replication

ABSTRACT The human cytomegalovirus (HCMV) UL76 gene encodes a highly conserved herpesvirus protein, pUL76, which is able to modulate gene expression in either activation or repression. In this study, two specific transcripts were found to contain the reading frame of UL76, one a 4.5-kb and the other a 5.5-kb tricistronic mRNA encoding the UL76, UL77, and UL78 open reading frames. Both transcripts were expressed with true late kinetics, as revealed by data showing inhibition of production in the presence of phosphonoformic acid. Immediately after viral infection, pUL76 was found in the nuclear fraction and was detected in cells in the presence of the protein synthesis inhibitor cycloheximide. Subsequent virus particle purification and Western blot analysis revealed that two forms of pUL76 are associated within mature virions. The high-molecular-mass protein (H-pUL76) was verified as originating from a free form of pUL76 by cross-linking with an unknown protein(s). By performing a biochemical fractionation experiment with purified virions, we provide evidence that pUL76 and H-pUL76 are associated with the detergent-soluble (envelope) and -insoluble (tegument/capsid) fractions, respectively. Both results were consistent with the images exhibited by immunoelectron microscopy, which showed that the distribution of gold particles labeled by the anti-pUL76 antibody juxtaposed the compartments of the envelope and the tegument/capsid of the virion. Evidence indicated that expression of pUL76 at the immediate-early phase of the viral replication cycle leads to the inhibition of HCMV production. The viral constituent pUL76, with a dominant-negative effect on replication, may provide a novel mechanism for HCMVs resumption of latency.

New Cytotoxic Cembranolides from the Soft Coral Lobophytum michaelae

Six new cembranolides, michaolides L–Q (1–6), and a known cembranolide, lobomichaolide (7) were isolated from the CH2Cl2 extract of the soft coral Lobophytum michaelae. Their structures were established by extensive spectral analysis. The anti-HCMV (human cytomegalovirus) activity of 1–7 and their cytotoxicity against selected cell lines were evaluated.

Lobocrasol, a New Diterpenoid from the Soft Coral Lobophytum crassum

Lobocrasol (1), possessing an unprecedented diterpenoid skeleton, was isolated from the soft coral Lobophytum crassum. The structure of lobocrasol was established by extensive analysis of spectroscopic data.