Comprehensive Cell Biological Investigation of Cytochalasin B Derivatives with Distinct Activities on the Actin Network.

In search of a more comprehensive structure-activity relationship (SAR) regarding the inhibitory effect of cytochalasin B (2) on actin polymerization, a virtual docking of 2 onto monomeric actin was conducted. This led to the identification of potentially important functional groups of 2 (i.e., the NH group of the isoindolone core (N-2) and the hydroxy groups at C-7 and C-20) involved in interactions with the residual amino acids of the binding pocket of actin. Chemical modifications of 2 at positions C-7, N-2, and C-20 led to derivatives 3-6, which were analyzed for their bioactivities. Compounds 3-5 exhibited reduced or no cytotoxicity in murine L929 fibroblasts compared to that of 2. Moreover, short- and long-term treatments of human osteosarcoma cells (U-2OS) with 3-6 affected the actin network to a variable extent, partially accompanied by the induction of multinucleation. Derivatives displaying acetylation at C-20 and N-2 were subjected to slow intracellular conversion to highly cytotoxic 2. Together, this study highlights the importance of the hydroxy group at C-7 and the NH function at N-2 for the potency of 2 on the inhibition of actin polymerization.

Mitochondrial aggregation caused by cytochalasin B compromises the efficiency and safety of three-parent embryo.

It is widely accepted that cytochalasin B (CB) is required in enucleation of the oocyte in order to stabilize the cytoplasm. However, CB treatment results in the uneven distribution of mitochondria, with aggregation towards the nucleus, which might compromise the efficiency and safety of a three-parent embryo. Here, we demonstrated that CB treatment affected mitochondrial dynamics, spindle morphology and mitochondrial DNA carryover in a concentration-dependent manner. Our results showed that mouse oocytes treated with over 1 µg/ml CB exhibited a more aggregated pattern of mitochondria and diminished filamentous actin expression. Abnormal fission of mitochondria together with changes in spindle morphology increased as CB concentration escalated. Based on the results of mouse experiments, we further revealed the practical value of these findings in human oocytes. Chip-based digital PCR and pyrosequencing revealed that the mitochondrial carryover in reconstituted human embryos was significantly reduced by modifying the concentration of CB from the standard 5 µg/ml to 1 µg/ml before spindle transfer and pronuclear transfer. In conclusion, our findings provide an optimal manipulation for improving the efficiency and safety of mitochondrial replacement therapy.

New Cytochalasin Derivatives from Deep-Sea Cold Seep-Derived Endozoic Fungus Curvularia verruculosa CS-129.

Two new antimicrobial cytochalasin derivatives, 6ß,7ß-epoxydeoxaphomin C (1) and 12-hydroxydeoxaphomin C (2), a new natural occurring product 24-nor-cytochalasin B (3), together with two related known analogs (4-5) were isolated and identified from an endozoic fungus Curvularia verruculosa CS-129, isolated from the deep-sea squat lobster Shinkaia crosnieri which was collected in cold seep region of south China sea. The structures of new compounds were elucidated on the basis of detailed spectroscopic analysis and ECD calculation. The spectroscopic data of 24-nor-cytochalasin B (3) were reported for the first time. All compounds were tested for their antibacterial activities against human and aquatic pathogenic bacteria.

Beta Human Papillomavirus 8E6 Attenuates LATS Phosphorylation after Failed Cytokinesis.

Beta genus human papillomaviruses (ß-HPVs) cause cutaneous squamous cell carcinomas (cSCCs) in a subset of immunocompromised patients. However, ß-HPVs are not necessary for tumor maintenance in the general population. Instead, they may destabilize the genome in the early stages of cancer development. Supporting this idea, ß-HPV's 8E6 protein attenuates p53 accumulation after failed cytokinesis. This paper offers mechanistic insight into how ß-HPV E6 causes this change in cell signaling. An in silico screen and characterization of HCT 116 cells lacking p300 suggested that the histone acetyltransferase is a negative regulator of Hippo pathway (HP) gene expression. HP activation restricts growth in response to stimuli, including failed cytokinesis. Loss of p300 resulted in increased HP gene expression, including proproliferative genes associated with HP inactivation. ß-HPV 8E6 expression recapitulates some of these phenotypes. We used a chemical inhibitor of cytokinesis (dihydrocytochalasin B [H2CB]) to induce failed cytokinesis. This system allowed us to show that ß-HPV 8E6 reduced activation of large tumor suppressor kinase (LATS), an HP kinase. LATS is required for p53 accumulation following failed cytokinesis. These phenotypes were dependent on ß-HPV 8E6 destabilizing p300 and did not completely attenuate the HP. It did not alter H2CB-induced nuclear exclusion of the transcription factor YAP. ß-HPV 8E6 also did not decrease HP activation in cells grown to a high density. Although our group and others have previously described inhibition of DNA repair, to the best of our knowledge, this marks the first time that a ß-HPV E6 protein has been shown to hinder HP signaling.IMPORTANCE ß-HPVs contribute to cSCC development in immunocompromised populations. However, it is unclear if these common cutaneous viruses are tumorigenic in the general population. Thus, a more thorough investigation of ß-HPV biology is warranted. If ß-HPV infections do promote cSCCs, they are hypothesized to destabilize the cellular genome. In vitro data support this idea by demonstrating the ability of the ß-HPV E6 protein to disrupt DNA repair signaling events following UV exposure. We show that ß-HPV E6 more broadly impairs cellular signaling, indicating that the viral protein dysregulates the HP. The HP protects genome fidelity by regulating cell growth and apoptosis in response to a myriad of deleterious stimuli, including failed cytokinesis. After failed cytokinesis, ß-HPV 8E6 attenuates phosphorylation of the HP kinase (LATS). This decreases some, but not all, HP signaling events. Notably, ß-HPV 8E6 does not limit senescence associated with failed cytokinesis.

Characterizing Different Probiotic-Derived Extracellular Vesicles as a Novel Adjuvant for Immunotherapy.

Extracellular vesicles (EVs) secreted from probiotics, defined as live microorganisms with beneficial effects on the host, are expected to be new nanomaterials for EV-based therapy. To clarify the usability of probiotic-derived EVs in terms of EV-based therapy, we systematically evaluated their characteristics, including the yield, physicochemical properties, the cellular uptake mechanism, and biological functions, using three different types of probiotics: Bifidobacterium longum, Clostridium butyricum, and Lactobacillus plantarum WCFS1. C. butyricum secreted the largest amounts of EVs, whereas all the EVs showed comparable particle sizes and zeta potentials, ranging from 100 to 150 nm and -8 to -10 mV, respectively. The silkworm larvae plasma assay indicated that these EVs contain peptidoglycan that activates the host's immune response. Moreover, a cellular uptake study of probiotic-derived EVs in RAW264.7 cells (mouse macrophage-like cells) and DC2.4 cells (mouse dendritic cells) in the presence of inhibitors (cytochalasin B, chlorpromazine, and methyl-ß-cyclodextrin) revealed that probiotic-derived EVs were mainly taken up by these immune cells via clathrin-mediated endocytosis and macropinocytosis. Furthermore, all the probiotic-derived EVs stimulated the innate immune system through the production of inflammatory cytokines (TNF-α and IL-6) from these immune cells, clarifying their utility as a novel adjuvant formulation. These findings on probiotic-derived EVs are valuable for understanding the biological significance of probiotic-derived EVs and the development of EV-based immunotherapy.

Cherbonolides M and N from a Formosan Soft Coral Sarcophyton cherbonnieri.

Two new isosarcophine derivatives, cherbonolides M (1) and N (2), were further isolated from a Formosan soft coral Sarcophyton cherbonnieri. The planar structure and relative configuration of both compounds were established by the detailed analysis of the IR, MS, and 1D and 2D NMR data. Further, the absolute configuration of both compounds was determined by the comparison of CD spectra with that of isosarcophine (3). Notably, cherbonolide N (2) possesses the unique cembranoidal scaffold of tetrahydrooxepane with the 12,17-ether linkage fusing with a γ-lactone. In addition, the assay for cytotoxicity of both new compounds revealed that they showed to be noncytotoxic toward the proliferation of A549, DLD-1, and HuCCT-1 cell lines. Moreover, the anti-inflammatory activities of both metabolites were carried out by measuring the N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLF/CB)-induced generation of superoxide anion and elastase release in the primary human neutrophils. Cherbonolide N (2) was found to reduce the generation of superoxide anion (20.6 ± 6.8%) and the elastase release (30.1 ± 3.3%) in the fMLF/CB-induced human neutrophils at a concentration of 30 µM.

Suitability of the In Vitro Cytokinesis-Block Micronucleus Test for Genotoxicity Assessment of TiO2 Nanoparticles on SH-SY5Y Cells.

Standard toxicity tests might not be fully adequate for evaluating nanomaterials since their unique features are also responsible for unexpected interactions. The in vitro cytokinesis-block micronucleus (CBMN) test is recommended for genotoxicity testing, but cytochalasin-B (Cyt-B) may interfere with nanoparticles (NP), leading to inaccurate results. Our objective was to determine whether Cyt-B could interfere with MN induction by TiO2 NP in human SH-SY5Y cells, as assessed by CBMN test. Cells were treated for 6 or 24 h, according to three treatment options: co-treatment with Cyt-B, post-treatment, and delayed co-treatment. Influence of Cyt-B on TiO2 NP cellular uptake and MN induction as evaluated by flow cytometry (FCMN) were also assessed. TiO2 NP were significantly internalized by cells, both in the absence and presence of Cyt-B, indicating that this chemical does not interfere with NP uptake. Dose-dependent increases in MN rates were observed in CBMN test after co-treatment. However, FCMN assay only showed a positive response when Cyt-B was added simultaneously with TiO2 NP, suggesting that Cyt-B might alter CBMN assay results. No differences were observed in the comparisons between the treatment options assessed, suggesting they are not adequate alternatives to avoid Cyt-B interference in the specific conditions tested.

Tracking Fenestrae Dynamics in Live Murine Liver Sinusoidal Endothelial Cells.

The fenestrae of liver sinusoidal endothelial cells (LSECs) allow passive transport of solutes, macromolecules, and particulate material between the sinusoidal lumen and the liver parenchymal cells. Until recently, fenestrae and fenestrae-associated structures were mainly investigated using electron microscopy on chemically fixed LSECs. Hence, the knowledge about their dynamic properties has remained to date largely elusive. Recent progress in atomic force microscopy (AFM) has allowed the study of live cells in three dimensions (X, Y, and Z) over a prolonged time (t) and this at unprecedented speeds and resolving power. Hence, we employed the latest advances in AFM imaging on living LSECs. As a result, we were able to monitor the position, size, and number of fenestrae and sieve plates using four-dimensional AFM (X, Y, Z, and t) on intact LSECs in vitro. During these time-lapse experiments, dynamic data were collected on the origin and morphofunctional properties of the filtration apparatus of LSECs. We present structural evidence on single laying and grouped fenestrae, thereby elucidating their dynamic nature from formation to disappearance. We also collected data on the life span of fenestrae. More especially, the formation and closing of entire sieve plates were observed, and how the continuous rearrangement of sieve plates affects the structure of fenestrae within them was recorded. We observed also the dawn and rise of fenestrae-forming centers and defenestration centers in LSECs under different experimental conditions. Conclusion: Utilizing a multimodal biomedical high-resolution imaging technique we collected fine structural information on the life span, formation, and disappearance of LSEC fenestrae; by doing so, we also gathered evidence on three different pathways implemented in the loss of fenestrae that result in defenestrated LSECs.

The strengths and weaknesses of viscoelastic testing compared to traditional coagulation testing.

Optimized acute bleeding management requires timely and reliable laboratory testing to detect and diagnose coagulopathies and guide transfusion therapy. Conventional coagulation tests (CCT) are inexpensive with minimal labor requirements, but CCTs may have delayed turnaround times. In addition, abnormal CCT values may not reflect in vivo coagulopathies that require treatment and may lead to overtransfusion. The use of viscoelastic testing (VET) has been rapidly expanding and is recommended by several recent bleeding guidelines. This review is intended to compare CCT to VET, review the strengths and weaknesses of both approaches, and evaluate and summarize the clinical studies that compared CCT-based and VET-based transfusion algorithms. Most studies of CCT vs VET transfusion algorithms favor the use of VET in the management of massively bleeding patients due to reductions in blood product utilization, bleeding, costs, and lengths of stay.

Cytoskeleton-disrupting agent cytochalasin B reduces oxidative stress caused by high glucose in the human arterial smooth muscle.

The role of cytoskeleton dynamics in the oxidative stress toward human vasculature has been unclear. The current study examined whether the cytoskeleton-disrupting agent cytochalasin B reduces oxidative stress caused by high glucose in the human arterial smooth muscle. All experiments in the human omental arteries without endothelium or the cultured human coronary artery smooth muscle cells were performed in d-glucose (5.5 mmol/L). The exposure toward d-glucose (20 mmol/L) for 60 min reduced the relaxation or hyperpolarization to an ATP sensitive K+ channel (KATP) opener levcromakalim (10-8 to 3 × 10-6 mol/L and 3 × 10-6 mol/L, respectively). Cytochalasin B and a superoxide inhibitor Tiron, restored them similarly. Cytochalasin B reduced the NADPH oxidase activity, leading to a decrease in superoxide levels of the arteries treated with high d-glucose. Also, cytochalasin B impaired the F-actin constitution and the membrane translocation of an NADPH oxidase subunit p47phox in artery smooth muscle cells treated with high d-glucose. A clinical concentration of cytochalasin B prevented human vascular smooth muscle malfunction via the oxidative stress caused by high glucose. Regulation of the cytoskeleton may be essential to keep the normal vascular function in patients with hyperglycemia.

Comparative analysis of cell-free DNA content in culture medium and mitochondrial DNA copy number in porcine parthenogenetically activated embryos.

We examined the effect of ploidy on mitochondrial DNA (mtDNA) copy number in embryos and the amount of cell-free mitochondrial and nucleic DNA content (cf-mtDNA and cf-nDNA) in spent culture medium (SCM). Oocytes collected from the ovaries were matured, activated, incubated in medium containing cycloheximide (CHX) or CHX and cytochalasin B (CB) for 4.5 h to produce haploid or diploid embryos (H-group and D-group embryos). These embryos were cultured for 7 days, and the blastocysts and SCM were examined. The amount of mtDNA and nDNA was determined by real-time PCR. The rate of development to the blastocyst stage was higher for the D-group than for the H-group. Moreover, D-group blastocysts had less mtDNA compared to the H-group blastocysts. After activation, the mitochondrial content was constant before the blastocyst stage in D-group embryos, but increased earlier in H-group embryos. The amount of cf-mtDNA in the SCM of D-group blastocysts was greater than that of H-group blastocysts. However, when the cf-mtDNA in the SCM of 2 cell-stage embryos (day 2 post-activation) was examined, the amount of cf-mtDNA was greater in the H-group than in the D-group embryos. When D-group embryos were cultured for 7 days, a significant correlation was observed between the total cell number of blastocysts and cf-nDNA content in the SCM. Hence, although careful consideration is needed regarding the time point for evaluating mtDNA content in the embryos and SCM, this study demonstrates that mtDNA in the embryos and SCM was affected by the ploidy of the embryos.

Route to Rheumatoid Arthritis by Macrophage-Derived Microvesicle-Coated Nanoparticles.

The targeted delivery of therapeutics to sites of rheumatoid arthritis (RA) has been a long-standing challenge. Inspired by the intrinsic inflammation-targeting capacity of macrophages, a macrophage-derived microvesicle (MMV)-coated nanoparticle (MNP) was developed for targeting RA. The MMV was efficiently produced through a novel method. Cytochalasin B (CB) was applied to relax the interaction between the cytoskeleton and membrane of macrophages, thus stimulating MMV secretion. The proteomic profile of the MMV was analyzed by iTRAQ (isobaric tags for relative and absolute quantitation). The MMV membrane proteins were similar to those of macrophages, indicating that the MMV could exhibit bioactivity similar to that of RA-targeting macrophages. A poly(lactic- co-glycolic acid) (PLGA) nanoparticle was subsequently coated with MMV, and the inflammation-mediated targeting capacity of the MNP was evaluated both in vitro and in vivo. The in vitro binding of MNP to inflamed HUVECs was significantly stronger than that of the red blood cell membrane-coated nanoparticle (RNP). Compared with bare NP and RNP, MNP showed a significantly enhanced targeting effect in vivo in a collagen-induced arthritis (CIA) mouse model. The targeting mechanism was subsequently revealed according to the proteomic analysis, indicating that Mac-1 and CD44 contributed to the outstanding targeting effect of the MNP. A model drug, tacrolimus, was encapsulated in MNP (T-RNP) and significantly suppressed the progression of RA in mice. The present study demonstrates MMV as a promising and rich material, with which to mimic macrophages, and demonstrates that MNP is an efficient biomimetic vehicle for RA targeting and treatment.

Secoiridoid Glucosides and Anti-Inflammatory Constituents from the Stem Bark of Fraxinus chinensis.

Qin Pi (Fraxinus chinensis Roxb.) is commercially used in healthcare products for the improvement of intestinal function and gouty arthritis in many countries. Three new secoiridoid glucosides, (8E)-4''-O-methylligstroside (1), (8E)-4''-O-methyldemethylligstroside (2), and 3'',4''-di-O-methyl-demethyloleuropein (3), have been isolated from the stem bark of Fraxinus chinensis, together with 23 known compounds (4-26). The structures of the new compounds were established by spectroscopic analyses (1D, 2D NMR, IR, UV, and HRESIMS). Among the isolated compounds, (8E)-4''-O-methylligstroside (1), (8E)-4''-O-methyldemethylligstroside (2), 3'',4''-di-O-methyldemethyloleuropein (3), oleuropein (6), aesculetin (9), isoscopoletin (11), aesculetin dimethyl ester (12), fraxetin (14), tyrosol (21), 4-hydroxyphenethyl acetate (22), and (+)-pinoresinol (24) exhibited inhibition (IC50 ≤ 7.65 µg/mL) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leuckyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 1, 9, 11, 14, 21, and 22 inhibited fMLP/CB-induced elastase release with IC50 ≤ 3.23 µg/mL. In addition, compounds 2, 9, 11, 14, and 21 showed potent inhibition with IC50 values ≤ 27.11 µM, against lipopolysaccharide (LPS)-induced nitric oxide (NO) generation. The well-known proinflammatory cytokines, tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6), were also inhibited by compounds 1, 9, and 14. Compounds 1, 9, and 14 displayed an anti-inflammatory effect against NO, TNF-α, and IL-6 through the inhibition of activation of MAPKs and IκBα in LPS-activated macrophages. In addition, compounds 1, 9, and 14 stimulated anti-inflammatory M2 phenotype by elevating the expression of arginase 1 and Krüppel-like factor 4 (KLF4). The above results suggested that compounds 1, 9, and 14 could be considered as potential compounds for further development of NO production-targeted anti-inflammatory agents.

Bioactive Capnosanes and Cembranes from the Soft Coral Klyxum flaccidum.

Two new capnosane-based diterpenoids, flaccidenol A (1) and 7-epi-pavidolide D (2), two new cembranoids, flaccidodioxide (3) and flaccidodiol (4), and three known compounds 5 to 7 were characterized from the marine soft coral Klyxum flaccidum, collected off the coast of the island of Pratas. The structures of the new compounds were determined by extensive spectroscopic analyses, including 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, and spectroscopic data comparison with related structures. The rare capnosane diterpenoids were isolated herein from the genus Klyxum for the first time. The cytotoxicity of compounds 1 to 7 against the proliferation of a limited panel of cancer cell lines was assayed. The isolated diterpenoids also exhibited anti-inflammatory activity through suppression of superoxide anion generation and elastase release in the N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLF/CB)-stimulated human neutrophils. Furthermore, 1 and 7 also exhibited cytotoxicity toward the tested cancer cells, and 7 could effectively inhibit elastase release. It is worth noting that the biological activities of 7 are reported for the first time in this paper.

Chemical Constituents of Vigna luteola and Their Anti-inflammatory Bioactivity.

Seventy-three compounds were identified from the methanol extract of V. luteola, and among these, three new (1⁻3) were characterized by spectroscopic and mass spectrometric analyses. The isolated constituents were assessed for anti-inflammatory potential evaluation, and several purified principles exhibited significant superoxide anion and elastase inhibitory effects.

Disassembly of Subplasmalemmal Actin Filaments Induces Cytosolic Ca2+ Increases in Astropecten aranciacus Eggs.

BACKGROUND/AIMS: Eggs of all animal species display intense cytoplasmic Ca2+ increases at fertilization. Previously, we reported that unfertilized eggs of Astropecten aranciacus exposed to an actin drug latrunculin A (LAT-A) exhibit similar Ca2+ waves and cortical flashes after 5-10 min time lag. Here, we have explored the molecular mechanisms underlying this unique phenomenon. METHODS: Starfish eggs were pretreated with various agents such as other actin drugs or inhibitors of phospholipase C (PLC), and the changes of the intracellular Ca2+ levels were monitored by use of Calcium Green in the presence or absence of LAT-A. The concomitant changes of the actin cytoskeleton were visualized with fluorescent F-actin probes in confocal microscopy. RESULTS: We have shown that the LAT-A-induced Ca2+ increases are related to the disassembly of actin flaments: i) not only LAT-A but also other agents depolymerizing F-actin (i.e. cytochalasin B and mycalolide B) induced similar Ca2+ increases, albeit with slightly lower efficiency; ii) drugs stabilizing F-actin (i.e. phalloidin and jasplakinolide) either blocked or significantly delayed the LAT-A-induced Ca2+ increases. Further studies utilizing pharmacological inhibitors of PLC (U-73122 and neomycin), dominant negative mutant of PLC-É£, specific sequestration of PIP2 (RFP-PH), InsP3 uncaging, and quantitation of endogenous InsP3 all indicated that LAT-A induces Ca2+ increases by stimulating PLC rather than sensitizing InsP3 receptors. In support of the idea, it bears emphasis that LAT-A timely increased intracellular contents of InsP3 with concomitant decrease of PIP2 levels in the plasma membrane. CONCLUSION: Taken together, our results suggest that suboolemmal actin filaments may serve as a scaffold for cell signaling and modulate the activity of the key enzyme involved in intracellular Ca2+ signaling.

Kinetic Basis of Cis- and Trans-Allostery in GLUT1-Mediated Sugar Transport.

A growing body of evidence demonstrates that GLUT1-mediated erythrocyte sugar transport is more complex than widely assumed and that contemporary interpretations of emergent GLUT1 structural data are incompatible with the available transport and biochemical data. This study examines the kinetic basis of one such incompatibility-transport allostery-and in doing so suggests how the results of studies examining GLUT1 structure and function may be reconciled. Three types of allostery are observed in GLUT1-mediated, human erythrocyte sugar transport: (1) exofacial cis-allostery in which low concentrations of extracellular inhibitors stimulate sugar uptake while high concentrations inhibit transport; (2) endofacial cis-allostery in which low concentrations of intracellular inhibitors enhance cytochalasin B binding to GLUT1 while high concentrations inhibit binding, and (3) trans-allostery in which low concentrations of ligands acting at one cell surface stimulate ligand binding at or sugar transport from the other surface while high concentrations inhibit these processes. We consider several kinetic models to account for these phenomena. Our results show that an inhibitor can only stimulate then inhibit sugar uptake if (1) the transporter binds two or more molecules of inhibitor; (2) high-affinity binding to the first site stimulates transport, and (3) low-affinity binding to the second site inhibits transport. Reviewing the available structural, transport, and ligand binding data, we propose that exofacial cis-allostery results from cross-talk between multiple, co-existent ligand interaction sites present in the exofacial cavity of each GLUT1 protein, whereas trans-allostery and endofacial cis-allostery require ligand-induced subunit-subunit interactions.

Label-free imaging of epidermal growth factor receptor-induced response in single living cells.

Epidermal growth factor receptor (EGFR), which belongs to the second-largest protein family for cell signal transduction, plays crucial roles in homeostasis, cellular organized patterns and most human cancers. In EGFR-activated signaling networks, the detection of the spatial and temporal dynamics of cascades that encode the many cell fates is still a challenge. Here, we report real-time imaging of epidermal growth factor (EGF)-induced EGFR activation and its signaling cascade in single A431 cells using surface plasmon resonance (SPR) microscopy. A two-phase SPR response pattern was observed within 30 min after EGF treatment, including a positive SPR response that was related to the EGFR-activated mass redistribution in the first 600 s, and a subsequent negative SPR signal caused by the morphological change of the cells. Furthermore, the inhibitor analysis verified that AG1478 inhibited the response from the whole the cell, whereas cytochalasin B strongly inhibited the response from the cell edge region.

Anti-Inflammatory Polyoxygenated Steroids from the Soft Coral Lobophytum michaelae.

Three new polyoxygenated steroids, michosterols A-C (1-3), and four known compounds (4-7) were isolated from the ethyl acetate (EtOAc) extract of the soft coral Lobophytum michaelae, collected off the coast of Taitung. The structures of the new compounds were elucidated on the basis of spectroscopic analyses and comparison of the nuclear magnetic resonance (NMR) data with related steroids. The cytotoxicity of compounds 1-3 against the proliferation of a limited panel of cancer cell lines was assayed. Compound 1 was found to display moderate cytotoxicity against adenocarcinomic human alveolar basal epithelial (A549) cancer cells. It also exhibited potent anti-inflammatory activity by suppressing superoxide anion generation and elastase release in N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLP/CB)-stimulated human neutrophils. Furthermore, 3 could effectively inhibit elastase release, as well.

New Cembranoids and a Biscembranoid Peroxide from the Soft Coral Sarcophyton cherbonnieri.

Six new cembranoids, cherbonolides A-E (1⁻5) and bischerbolide peroxide (6), along with one known cembranoid, isosarcophine (7), were isolated from the Formosan soft coral Sarcophyton cherbonnieri. The structures of these compounds were elucidated by detailed spectroscopic analysis and chemical methods. Compound 6 was discovered to be the first example of a molecular skeleton formed from two cembranoids connected by a peroxide group. Compounds 1⁻7 were shown to have the ability of inhibiting the production of superoxide anions and elastase release in N-formyl-methionyl-leucyl-phenyl-alanine/cytochalasin B (fMLF/CB)-induced human neutrophils.