Total synthesis of the active resveratrol dimer dehydro-δ-viniferin

A new approach for the total synthesis of the active stilbene dimer dehydro-δ-viniferin has been achieved in 9 steps with methyl 4-hydroxybenzoate and 3,5-dihydroxyacetophenone as starting materials. The key feature of the method is the amberlyst 15-mediated cyclodehydration of α-aryloxyketone. [Formula: see text].

Discovery of a semi-synthesized cyclolignan as a potent HIV-1 non-nucleoside reverse transcriptase inhibitor

Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are essential components of highly active antiretroviral therapy (HAART) for human immunodeficiency virus type 1 (HIV-1) infection. In this study, we identified (+)-(7'S,8S,8'S)-3',4,4',5,5'-pentamethoxy-2,7'-cyclolignan (SG-1), a cyclolignan semi-synthesized from Machilus robusta and M. wangchiana extracts, as a potent NNRTI. SG-1 displayed anti-HIV-1 activity with an IC₅₀ of 0.77 μmol/L by inhibiting reverse transcriptase (RT) RNA-dependent DNA polymerase activity through a direct binding. It had synergistic effects when combined with tenofovir/lamivudine or zidovudine/lamivudine. The pharmacodynamics properties of SG-1 render it a valuable lead for the development of novel NNRTIs.

Naturally active oligostilbenes

Many naturally occurring oligostilbenes have drawn considerable attention because of their intricate structures and diverse biological activities. In recent years, oligostilbene bioactivities have become a popular research topic worldwide. Although these bioactivities are known to be extensive and several summaries on the activities of the compounds have been published, a comprehensive and systematic summary on active oligostilbenes is unavailable. From January 2005 to December 2013, a large number of active oligostilbenes and corresponding new bioactivities were reported in the literature. This review mainly focuses on the diverse bioactivities of oligostilbenes with various backbones.

Cyanogenetic glycosides and simple glycosides from the linseed meal

Three new cyanogenetic triglycosides linustatins A-C (1-3), and two new simple glycosides linustatins D and E (4 and 5) were isolated from the 70% ethanol extract of flaxseed meal (Linum usitatissimum L.). Their structures were elucidated on the basis of spectroscopic analysis and chemical evidence. All of the isolates showed moderate activities against aldose reductase and weak activities against α-glucosidase, DPP-IV, and FBPase at the same concentrations as the positive control drugs.

Biomimetic synthesis of active isorhapontigenin dimers

Synthetic isorhapontigenin was treated with several kinds of inorganic reagents and peroxidase so as to prepare active stilbene dimers. Among them, silver acetate in methanol gave two new isorhapontigenin dimers 4 and 5, together with four known natural stilbene dimers 2, 3, 6, and 7. Their structures and relative configurations were determined on the basis of spectral analysis, and their possible formation mechanisms were discussed, respectively. Compounds 2, 6, and 7 were artificially synthesized for the first time. All the products were evaluated for anti-inflammatory activities.

[Effects of Vam3 on sodium nitroprusside-induced apoptosis and SIRT1 and p53 expression in rat articular chondrocytes]

This study is to investigate the effect of Vam3, a dimeric derivative of resveratrol, on SNP-induced apoptosis and its potential mechanism in rat articular chondrocytes. Isolated rat articular chondrocytes were treated with sodium nitroprusside (SNP), a NO donor, to induce apoptosis. Apoptosis percentage was evaluated by Annexin V-PI and nucleus fracture was examined by DAPI staining. Level of intracellular reactive oxygen species (ROS) was detected using 2, 7'-dichlorofluorescin diacetate (DCFH-DA) as a fluorescence probe by fluorescence microplate reader. The change in mitochondrial membrane potential was detected by TMRE staining. Expressions of SIRT1, acetylated p53 (ac-p53), cleaved caspase 9 and cleaved caspase 3 were determined by Western blotting. It showed that Vam3 up to 10 micromol x L(-1) could significantly reduce SNP-induced rat articular chondrocytes apoptosis (P < 0.01) and nucleus fracture, inhibit the increase of intracellular ROS level (P < 0.01) and reverse the decrease in mitochondrial membrane potential (P < 0.01). Simultaneously, Vam3 could upregulate the expression of SIRT1, deacetylate p53, and inhibit the cleavage of caspase 9 and caspase 3 (P < 0.01) of rat articular chondrocytes exposed to SNP. This study indicates Vam3 could protect rat articular chondrocytes against SNP-induced apoptosis, perhaps through the upregulation of SIRT1 and deacetylation of p53.

Significant association between lower pulse pressure and increasing levels of a novel type of phospholipid

The aim of this study was to analyze the association between pulse pressure and a novel type of phospholipid with solubility similar to that of lysophosphatidic acid (LPA), designated as AP, which was reported to be elevated during ischemia. In this cross-sectional study, 416 hypertensive patients and 252 controls aged between 35 and 70 years were enrolled consecutively. Fasting blood samples were extracted for assays of phospholipids and other biomarkers. Compared to controls, the hypertensive patients had higher levels of both LPA [odds ratio (OR) = 3.83] and AP (OR = 4.30). Changes in blood pressure did not affect the levels of LPA or AP. However AP, but not LPA, levels were significantly higher in patients with lower or higher pulse pressure (Pearson χ(2) = 11.239, P = 0.001). For patients whose pulse pressure was ≤60 mmHg, plasma levels of AP were significantly negatively correlated with pulse pressure. However, this was not observed for LPA and nine other biomarkers, including lipoproteins. Plasma levels of AP increased in hypertensive patients with higher or lower pulse pressure. Thus, attention should be paid to the possibility of cerebral ischemia in hypertensive patients when they have abnormal pulse pressure, especially for those with relatively low pulse pressure.

[Chemical constituents from the linseed meal]

Ten compounds were isolated from the 70% ethanol extract of linseed meal (Linum usitatissimum L) through a combination of various chromatographic techniques, including silica gel, macroporous adsorbent resin, Sephadex LH-20, and preparative HPLC. On the basis of spectroscopic data analysis, they were elucidated as 1-methylethyl-2-O-beta-D-glucopyranosyl-(1" --> 6')-beta-D-glucopyanoside (1), linustatin (2), neolinustatin (3), lotaustralin (4), linamarin (5), deoxyguanosine (6), deoxyadenosine (7), (+)-pinoresinol-4'-O-beta-D-glucopyranoside (8), 4-O-beta-D-glucopyranosylvanillyl alcohol (9) and tachioside (10), separately. Among them, compound 1 is a new compound, and compounds 6, 8 and 10 were isolated from the linseed meal for the first time.

A new stilbene dimer from Vitis amurensis

One new stilbene dimer named amurensin O (1), together with one known resveratrol trimer melapinol B (2), was isolated from Vitis amurensis, and their structures were identified on the basis of spectral analysis, especially 2D NMR spectral analysis.

A new resveratrol trimer derivative from Gnetum brunonianum

A new resveratrol trimer derivative, named as gnetubrunol A (1), together with five known stilbene derivatives, shegansu B (2), resveratrol (3), isorhapontigenin (4), gnetifolin E (5), and isorhapontigenin-11-O-β-d-glucopyranoside (6) were isolated from the lianas of Gnetum brunonianum Griff. Their structures were elucidated on the basis of spectral analysis (UV, IR, MS, (1)H NMR, (13)C NMR, and 2D NMR). The anti-inflammatory activities of 1, 5, and 6 have also been assayed.

A new triglucosylated naphthalene glycoside from Aloe vera L

A new triglucosylated naphthalene derivative, named aloveroside A (1), together with two known anthraquinone dimers and two 6-phenyl-2-pyrone derivatives, was isolated from the Aloe vera ethanolic extracts. The structure of 1 was established as 1-(((4-(1-O-beta-D-glucopyranosyl -(1-->4)-beta-D-xylopyranoside)-hydroxymethyl)-1-hydroxy-8-O-alpha-L-rhamnopyranoside)naphthalene-2-yl)-ethanone by means of spectroscopic evidences and chemical methods. All these compounds were tested for their BACE inhibitory activity but no significant activities were found.

BACE1 (beta-secretase) inhibitory chromone glycosides from Aloe vera and Aloe nobilis

Four new chromone glycosides allo-aloeresin D (2) , C-2'-decoumaroyl-aloeresin G (8), 2'-O-coumaroyl-(S)-aloesinol (9), 2'-O-[ P-methoxy-(E)-cinnamoyl]-(S)-aloesinol (10) and nine known chromone glycosides ( 1, 3 - 7, 11 - 13) were isolated from two Aloe spp. plants, A. vera and A. nobilis. Among them, 1 and 8 showed significant inhibitory activity against BACE1 (beta-secretase) with IC (50) values of 39.0 and 20.5 x 10 (-6) M, as well as inhibition of Abeta (1-42) production by 7.4 and 12.3 %, respectively, in B103 neuroblastoma cells at 30 ppm. The preliminary structure-activity relationships of ALOE chromone glucosides were also discussed.

[Active constituents from Aloe arborescens as BACE inhibitors]

AIM

To seek for new components as BACE inhibitors from Aloe arborescens.

METHODS

The chemical constituents were isolated by chromatographic methods and their structures were elucidated on the basis of spectral analysis.

RESULTS

Eight compounds were isolated and their structures identified as 6'-O-isobutyryl aloenin A (1), aloenin A (2), aloe-emodin (3), (E)-2-acetonyl-8-(2'-O-feruloxyl)-beta-D-glucopyranosyl-7-methoxy-5-methyl-chromone (4), 7-O-methylaloeresin A (5), babarloin A (6), elgonica-dimer A (7), and elgonica-dimer B (8), separately.

CONCLUSION

Compound 1 is a new compound, and compound 4 was isolated from A. arborescens for the first time. Pharmacological tests indicated that 2, 4, 5 and 6 have moderate inhibitory active on BACE.

Isolation and biomimetic synthesis of anti-inflammatory stilbenolignans from Gnetum cleistostachyum

One new stilbenolignan, gnetucleistol F (1), and four known stilbenolignans, gnetofuran A (2), lehmbachol D (3), gnetifolin F (4) and gnetumontanin C (5) were isolated from the lianas of Gnetum cleistostachyum C. Y. CHENG (Gnetaceae). Their structures and relative configurations were determined by means of spectroscopic evidence. Compounds 1, 2, 3 and 4 were synthesized for the first time on the basis of their biogenetic pathway, and their possible biomimetical synthetic mechanisms were discussed. The pharmacological activities of all stilbenolignans have been tested. Among them, 1, 2, 3, 4 and 5 showed moderate inhibitory activities on TNF-alpha and 1 also showed potent inhibitory activity on malondialdehyde.

Bioactive stilbene dimers from Gnetum cleistostachyum

Two new stilbene dimers, named bisisorhapontigenin A (1) and cis shegansu B (2), together with gnetuhainin P (3) and gnetulin (4), were isolated from the lianas of Gnetum cleistostachyum C. Y. Cheng. Their structures were elucidated by means of spectroscopic evidences, including UV, IR, MS, 1H NMR, 13C NMR, NOE and 2D NMR, respectively. The pharmacological activities of compounds 1, 2 and 3 also have been tested.

Anti-inflammatory effect of amurensin H on asthma-like reaction induced by allergen in sensitized mice

AIM

To explore the anti-inflammatory effects of amurensin H on asthma-like reaction induced by allergen in sensitized mice.

METHODS

BALB/c mice were sensitized by ovalbumin (OVA, ip) on d 0 and d 14 and challenged with 1% OVA on d 18 to 22. Mice developed airway eosinophilia, mucus hypersecretion, and elevation in cytokine levels. Mice were administered amurensin H orally at the doses of 49, 70, or 100 mg/kg once every day from d 15 to the last day. Bronchoalveolar lavage fluid (BALF) were collected at 24 h and 48 h after the last OVA challenge. Levels of tumor necrosis factor-alpha (TNF-alpha), interleukin 4 (IL-4), interleukin 5 (IL-5), and interleukin 13 (IL-13) in BALF were measured using ELISA method. Differential cell counts of macrophages, lymphocytes, neutrophils and eosinophils were performed in 200 cells per slide (one slide per animal). Lung tissue sections of 6-mum thickness were stained with Mayer's hematoxylin and eosin for assessment of cell infiltration, mucus production, and tissue damage.

RESULTS

Oral administration of amurensin H significantly inhibited OVA-induced increases in total cell counts, eosinophil counts, and TNF- alpha, IL-4, IL-5 and IL-13 levels in BALF. In addition, amuresin H dramatically decreased OVA-induced lung tissue damage and mucus production.

CONCLUSION

Amurensin H may have therapeutic potential for the treatment of allergic airway inflammation.

Stilbene derivatives from Gnetum cleistostachyum

Three new stilbene derivatives, named gnetucleistol A (1), B (2) and C (3), together with four known compounds, gnetifolin A (4), p-hydroxycinnamic acid (5), piceatannol (6) and resveratrol (7), were isolated from Gnetum cleistostachyum C.Y. Cheng (Gnetaceae). Their structures were elucidated on the basis of spectroscopic evidence (EI-MS, UV, IR, NOE, 1H, 13C and 2D NMR).

Preparation on Oligostilbenes of Isorhapontigenin by Oxidative Coupling Reaction

Four new compounds 1-4 were obtained from an oxidative coupling reaction of (E)-isorhapontigenin using FeCl(3) as oxidant. Their structures and stereochemistry were determined on the basis of spectroscopic evidence [UV, IR, MS, (1)H-, (13)C-NMR, NOE and 2D NMR], and their possible formation mechanisms were also discussed, respectively.

Synthesis and central nervous system depressant effects of N3-substituted 2',3'-O-isopropylideneuridines

N3-Substituted derivatives of 2',3'-O-isopropylideneuridine (1) were synthesized and their pharmacological effects on the central nervous system (CNS) examined using mice. Methyl (2), ethyl (3), propyl (4), butyl (5), allyl (6), benzyl (7), o-, m-, p-xylyls (8, 9, 10), and alpha-phenylethyl (11) derivatives of 1 were administered to mice by intracerebroventricular (i.c.v.) injection for evaluating hypnotic activity, pentobarbital-induced sleep prolongation, and spontaneous activity as indices. Only 3 possessed hypnotic activity by i.c.v. injection at the dose of 2.0 mumol/mouse. Compounds 3, 4, and 10 significantly showed synergism with a barbiturate, indicating that the derivatives have some CNS depressant effects. Moreover, 3 and 4 caused decrease in the spontaneous activity of mice, even at low doses. The present study indicated that substitution by ethyl, propyl, and p-xylyl groups at the N3-position of 2',3'-O-isopropylideneuridine imparted the CNS depressant effects.

Activation of epileptogenic activities by etomidate in electrocorticoencephalography (ECoG) during operation for epilepsy

Epileptic surgery is a radical and ablative treatment for medically refractory epilepsy. Electrocorticoencephalography (ECoG) obtained by subdural strip electrodes should always be used during operation for precise localization of epileptic focus and mapping the extent of its involvement. But difficulties and ambiguities exist when the patient's ECoG is suppressed, either owing to the anticonvulsant used, being at the stage of posterictal period, or the effects of anesthetics during operation. Then, intentional activation of epileptogenic activity should be performed to locate the pathological focus in order to accomplish a successful surgical treatment. Etomidate has been considered as an abnormal electroencephalogram (EEG) activator and its use is not recommended in patients with epilepsy. But lesser dose of etomidate as an activator for ECoG has not been investigated. The study reported here established that etomidate as an hypnotic has not only anesthetic properties but, paradoxically, also activates epileptogenic activity. With the latter pharmacologic characteristic, etomidate can be used to deliberately activate the spikes of the potentially epileptogenic tissue, the delineation and localization of which may help the surgeon determine to what extent the pathological cortex be resected in surgical treatment of a refractory epilepsy. The current recommended dosage of etomidate at veterans General Hospital-Taipei for ECoG in epileptic surgery is 0.1-0.15 mg/kg/iv.

Invasive papillomatosis and squamous carcinoma complicating juvenile laryngeal papillomatosis

Juvenile laryngeal papillomatosis (JLP), usually a benign, self-limited disease, occasionally has a highly aggressive course characterized by extension of neoplastic cells into the tracheobronchial tree, lung, and soft tissues. Less frequently, squamous carcinoma has arisen in JLP, most commonly following radiation therapy. Rarely, carcinoma has occurred without previous irradiation, but distant metastases do not generally occur. We describe a 14-year-old boy, with a particularly aggressive form of JLP, who developed invasion of the lungs, intrapulmonary lymph nodes, and arteries by cytologically benign neoplastic tissue. He also developed a metastasizing squamous carcinoma of the lung and humoral hypercalcemia of malignancy. A discussion of the implications of the case and a review of the current literature are provided.

Pulsed laser technique application to liquid and gaseous flows and the scattering power of seed materials

Mie scattering computations have been performed for light scattered by small particles from a pulsed sheet of laser illumination and collected and imaged by a camera lens. From these computations the smallest particles that can be photographed in various fluid measurement situations, including air and water, have been determined in terms of system parameters such as laser power, light sheet geometry, f/No., and photographic film properties. The particle scattering requirements of the individual particle image mode and the speckle mode are compared.

Estrogen induces different responses in dermal and lung fibroblasts: special reference to collagen

Fibroblast-like cells derived from dorsal skin and lung of AKR strain mouse embryos were cultured with estrogen for 4 days. The labeled hydroxyproline content was measured as newly synthesized collagenous protein in the cell layer and media. Although collagen synthesis by both cell lines was increased in both fractions under the influence of beta-estradiol-3-benzoate, at physiological concentrations of 10(-3)-10(-1) microgram/ml, the rate of increase differed. Fibroblasts derived from skin showed increased collagen synthesis of approximately 76%, while those from lung showed an increase of approximately 25%. Total protein synthesis by both cell lines also increased. In lung fibroblast cultures the synthesis of total protein was increased more than the synthesis of collagens; on the other hand in skin fibroblast cultures the synthesis of collagen was increased more than the synthesis of total protein. DNA synthesis by both cell lines was not affected by estrogen at the concentrations used. These findings suggest that fibroblasts develop in a different manner in each organ.

Investigation of the human macrophage. II. The in vitro cytotoxicity of macrophages

Macrophage-mediated cytotoxicity in vitro was studied by a tritiated thymidine incorporation inhibition assay as well as by microscopic examination and optical transmitance determination. It was found that macrophages from patients with malignant diseases showed cytotoxic effects on two malignant human cell lines. The cytotoxic activity was more marked in patients who were clinically tumor-free. Some patients with benign diseases and normal subjects also exhibited cytotoxic macrophages. Macrophage-mediated cytotoxicity (MMC) was thus nonspecific in nature. Cell-free exudate from cancer patients did not influence MMC appreciably. The experimental methods and the possible significance of MMC are discussed.

Investigation of the human macrophage. I. Collection and in vitro cultivation

By means of blister formation produced by cantharidin, a certain number of human macrophages could be readily obtained from the blister exudate. In the presence of 50% cell-free exudate, these cells were found to proliferate in vitro. The proliferating cells possessed the morphology and functional characteristics of macrophages.

Studies of factors influencing alveolar lining layer formation in lung homogenate: further isolation and identification of interfering materials

Materials which inhibit the formation of stable alveolar lining layer by lung surfactant were investigated with the pig lung homogenate. The inhibitory activity was assessed by the bubble stability test on the bubbles formed by mechanical agitation of a mixture of surface active fraction from lung homogenate and inhibitory materials. The most active inhibitory material was identified as free cholesterol. Free fatty acids had a remarkable inhibitory activity. By modified Wilhelmy balance, it was demonstrated that the addition of free cholesterol to the surface active fraction delayed the formation of the stable surface membrane and at a larger dosage it inhibited the lowering the surface tension at the minimum surface area. The significance of this phenomenon in pathological lungs was briefly discussed.

Experimental studies on the effect of aging and endocrine control on collagen formation in various organs

Physiological changes with advancing age of collagen content, fiber and fibril sizes in some connective tissues, the morphological profiles and enzyme histochemical activities of fibroblasts in different organs. and the effect of gonadectomy, adrenalectomy, hypophysectomy and their hormone replacement on the collagen and fibroblasts were studied using DDD, C57BL/6J, A/Jax, DW/J mice and Wistar rats. It was suggested that connective tissue in these organs was under the specific control of endocrine organs such as gonads, adrenals and the pituitary and that these controls might be effected through their hormonal effects on the specifically differentiated fibroblast localized in different organs and tissue.