Clot-Targeted Micellar Formulation Improves Anticoagulation Efficacy of Bivalirudin

Application of anticoagulants remains the primary strategy for prevention and treatment of thrombosis. However, high rate of bleeding complications limits their use. The peptide anticoagulant bivalirudin has been reported to exhibit a lower rate of bleeding complications than heparin, and it also has the advantage of not causing thrombocytopenia, which is a problem with heparin. Nonetheless, hemorrhage is the most common complication of bivalirudin therapy, and there is no effective antidote. Here we use a thrombus-binding peptide, CR(<i>N</i>Me)EKA, to accomplish selective delivery of the bivalirudin-carrying micellar nanocarrier to sites of thrombosis. Bivalirudin and CR(<i>N</i>Me)EKA, each with a PEG-lipid tail, spontaneously assembled into 30 nm micelles, which almost completely retained the anticoagulant activity of bivalirudin. The micellar formulations exhibited high stability both <i>in vitro</i> and <i>in vivo</i>. In a thromboplastin-induced mouse thrombosis model, the targeted micelles accumulated in lung thrombi 10-fold more than nontargeted micelles. Moreover, the micellar formulation significantly prolonged the half-life and thereby increased the bioavailability of bivalirudin. The micellar bivalirudin had significantly higher anticoagulant activity than free bivalirudin in both the lung thrombosis model and a ferric chloride-induced carotid artery thrombosis model. The specific targeting of thrombi demonstrated here makes it possible to increase the efficacy of bivalirudin as an anticoagulant. Alternatively, the dose could be reduced without loss of efficacy to lower the systemic exposure and improve safety

Anti-Respiratory Syncytial Virus Prenylated Dihydroquinolone Derivatives from the Gorgonian-Derived Fungus <i>Aspergillus</i> sp. XS-20090B15

Two new prenylated dihydroquinolone derivatives, 22-<i>O</i>-(<i>N</i>-Me-l-valyl)­aflaquinolone B (<b>1</b>) and 22-<i>O</i>-(<i>N</i>-Me-l-valyl)-21-<i>epi</i>-aflaquinolone B (<b>2</b>), and two known analogues, aflaquinolones A (<b>3</b>) and D (or a diastereomer of D, <b>4</b>), were isolated from the mycelia of a gorgonian-derived <i>Aspergillus</i> sp. fungus. The structures of the new compounds were elucidated by spectroscopic methods, ECD spectra, Marfey’s method, and chemical conversion. Compounds <b>1</b> and <b>2</b> display an unusual esterification of <i>N</i>-Me-l-Val to the side-chain prenyl group. Compound <b>2</b> exhibited outstanding anti-RSV activity with an IC₅₀ value of 42 nM, approximately 500-fold stronger than that of the positive control ribavirin (IC₅₀ = 20 μM), and showed a comparatively higher therapeutic ratio (TC₅₀/IC₅₀ = 520)

Structure and Absolute Configuration of Fumiquinazoline L, an Alkaloid from a Gorgonian-Derived <i>Scopulariopsis</i> sp. Fungus

Fumiquinazoline L (<b>1</b>), an alkaloid with a heptacyclic skeleton formed via a bridging hemiaminal linkage, was isolated from a gorgonian-derived <i>Scopulariopsis</i> sp. fungus. The structure and absolute configuration of the new compound were identified by comprehensive spectroscopic data and X-ray diffraction analysis. During acid hydrolysis of <b>1</b>, the isomerization of the valine residue was observed and also studied in different conditions. Fumiquinazoline L (<b>1</b>) showed no cytotoxic or antibacterial activities

Structure and Absolute Configuration of Fumiquinazoline L, an Alkaloid from a Gorgonian-Derived <i>Scopulariopsis</i> sp. Fungus

Fumiquinazoline L (<b>1</b>), an alkaloid with a heptacyclic skeleton formed via a bridging hemiaminal linkage, was isolated from a gorgonian-derived <i>Scopulariopsis</i> sp. fungus. The structure and absolute configuration of the new compound were identified by comprehensive spectroscopic data and X-ray diffraction analysis. During acid hydrolysis of <b>1</b>, the isomerization of the valine residue was observed and also studied in different conditions. Fumiquinazoline L (<b>1</b>) showed no cytotoxic or antibacterial activities

Lumazine Peptides Penilumamides B–D and the Cyclic Pentapeptide Asperpeptide A from a Gorgonian-Derived <i>Aspergillus</i> sp. Fungus

Three new lumazine peptides, penilumamides B–D (<b>2</b>–<b>4</b>), and one known analogue, penilumamide (<b>1</b>), together with a new cyclic pentapeptide, asperpeptide A (<b>5</b>), were isolated from the gorgonian-derived fungus <i>Aspergillus</i> sp. XS-20090B15. Among them, <b>2</b> was obtained from the feeding culture with l-methionine of this strain. All structures were elucidated by spectroscopic methods and chemical derivatization. Compounds <b>1</b>–<b>4</b> are rare lumazine peptides, of which <b>1</b> and <b>3</b> are formed from <b>2</b> by oxidation of the l-methionine residue

Metabolic and Cold Challenge Testing in Wild-type and NG2 Null Mice.

<p>(A and B) Volume of O₂ consumption (A) and CO₂ production (B) by 3-month old wild-type and NG2 null mice over 48 hours (Two light/dark cycles, n = 15). Data were normalized to body weights of individual mice. (C) Cold challenge testing of 3-month old male wild-type and NG2 null mice (n = 5). (D) Three month old male wild-type and NG2 null mice were put on HFD for 10 weeks and body temperatures were measured. As a control, body temperatures of five month old male wild-type and NG2 null mice on regular chow were measured (n = 6–7). (E) Levels of mRNA for brown fat-related genes in IBAT of wild-type and NG2 null mice maintained at room temperature or at 4°C for 6 hours (n = 3). *, P<0.05; **, P<0.01.</p

NG2 Null Mice are obese.

<p>(A and B) Body weight gain in wild-type and NG2 null mice. (C) Body weight and epididymal fat weight (grams) of 16-week old male wild-type and NG2 null mice (n = 6–10). (D) Body weight and weight of gonadal fat deposits in 16 week female mice (n = 7–9). (E) Dissected epididymal fat pads from 16-week old male wild-type and NG2 null mice. Fat pads are shown in 35-mm dishes. (F) Sizes of white fat cells in sections of epididymal fat pads from 16-week old male wild-type and NG2 null mice. Bar = 50 µm. (G) Numbers of fat cells per mm² (n = 5). (H) Expression of NG2 (Red), PDGFRα(Green) and CD31 (Blue) in sections through the ventromedial hypothalamic nucleus in both wild-type and OPC-NG2 Knockout mice. Note that yellow color in WT is due to red/green overlap. NG2 is not expressed by OPCs in the OPC-NG2 null mouse. Bar = 50 µm. (I) Body weight and epididymal fat weight in 16-week old wild-type and OPC-NG2 null mice (n = 8–9). (J and K) GTT (at 16 weeks) in male and Female wild-type and NG2 null mice (n = 5). (L) ITT (at 25 weeks) in male wild-type and NG2 null mice (n = 5). *, p<0.05; **, p<0.01.</p

Brown Fat Development in Wild-type and NG2 Null Mice.

<p>(A–C) Oil Red O staining of IBAT from P5 wild-type (A) and NG2 null (B) mice and quantification of Oil Red O staining intensity (C, n = 6). Bar = 50 µm. D. mRNA levels for brown fat-related genes in IBAT from P5 wild-type and NG2 null mice (n = 3). (E–H) Oil Red O staining of primary wild-type (E) and NG2 null (F) as well as immortalized wild-type (G) and NG2 null (H) pre-brown fat cells after 5 days of differentiation. Bar = 50 µm. (I–L) Immuno-fluorescence to detect NG2 and PDGFRβ in immortalized wild-type brown pre-adipocytes (I and K) and NG2 null brown pre-adipocytes (J and L). Bar = 100 µm. (M) Messenger RNA levels of PRDM16 and PGC1-α in immortalized pre-brown fat cells from wild-type and NG2 null mice (n = 3). *, P<0.05; **, P<0.01.</p

MEF Adipogenesis and Expression of NG2 in Adipocytes.

<p>(A and B) Oil red O staining to visualize differentiated adipocytes from wild-type (A) and NG2 null (B) MEFs. (C) Percentages of Oil red O stained cells <i>vs</i> total cells were determined in 10 randomly-selected high power fields. Results are quantified as Mean ± SEM. **, P<0.01. (D) Western blot analysis of NG2 protein in extracts of epididymal fat tissue from 3 month old wild-type and NG2 null mice. (E and F) Immunofluorescence labeling of NG2 in 20 µm-thick cryosections of epididymal fat tissue from 3-month old wild-type and NG2 null mice. (G and H) Immunofluorescence labeling of NG2 in 10 µm-thick cryosections of interscapular brown fat tissue from postnatal day 5 wild-type and NG2 null mice. Bar = 50 µm.</p

Bioactive Indole Alkaloids and Phenyl Ether Derivatives from a Marine-Derived <i>Aspergillus</i> sp. Fungus

Two new prenylated indole alkaloids, 17-<i>epi</i>-notoamides Q and M (<b>1</b> and <b>2</b>), and two new phenyl ether derivatives, cordyols D and E (<b>9</b> and <b>13</b>), together with 10 known compounds (<b>3</b>–<b>8</b>, <b>10</b>–<b>12</b>, <b>14</b>) were isolated from a marine-derived <i>Aspergillus</i> sp. fungus. Among them, <b>1</b>/<b>5</b> and <b>2</b>/<b>4</b> were pairs of epimers. The planar structures and absolute configurations of the new compounds were determined by extensive NMR spectroscopic data as well as CD spectra. The absolute configuration of <b>3</b> was confirmed by single-crystal X-ray diffraction analysis for the first time. All isolated metabolites (<b>1</b>–<b>14</b>) and eight synthetic phenyl ether derivatives (<b>12a</b>, <b>14a</b>–<b>14g</b>) were evaluated for their antibacterial activities <i>in vitro</i>. The polybromide phenyl ether <b>14g</b> showed pronounced antibacterial activity against <i>Staphylococcus epidermidis</i> with an MIC value of 0.556 μM, stronger than that of the positive control ciprofloxacin (MIC = 3.13 μM)