Scutellaria baicalensis Induces Cell Apoptosis and Elicits Mesenchymal-Epithelial Transition to Alleviate Metastatic Hepatocellular Carcinoma via Modulating HSP90ß.

Hepatocellular carcinoma is one of the most common malignant tumors in the world and shows strong metastatic potential. Current medicine for hepatocellular carcinoma therapy is invalid, while Scutellaria baicalensis Georgi exhibits the pharmaceutical potential to treat liver diseases and liver cancer. Herein, we verified the inhibitory properties and the pivotal molecules regimented by Scutellaria baicalensis on advanced hepatocellular carcinoma. At first, the viability of SK-Hep-1 cells was significantly reduced under treatment of Scutellaria baicalensis extract in a dose-dependent manner without affecting the growth of normal hepatocyte. Scutellaria baicalensis extract application could remarkably cause apoptosis of SK-Hep-1 cells through p53/cytochrome C/poly-ADP ribose polymerase cascades and arrest the cell cycle at the G1/S phase by downregulating cyclin-dependent kinases. Meanwhile, administration of Scutellaria baicalensis extract remarkably attenuated the migration capability as well as suppressed matrix metalloproteinase activity of advanced hepatocellular carcinoma cells. The proteome profiles and network analysis particularly implied that exposure to Scutellaria baicalensis extract downregulated the expression of HSP90ß, and the clinical stage of hepatocellular carcinoma is also positively correlated with the HSP90ß level. Combined treatment of Scutellaria baicalensis extract and HSP90ß siRNAs could markedly enhance the ubiquitination activity and the degradation of vimentin to subsequently inhibit the metastatic property of SK-Hep-1 cells. Moreover, application of Scutellaria baicalensis extract and HSP90ß siRNAs depleted phosphorylation of AKT, which stimulated the expression of p53 and consecutively triggered cell apoptosis. These findings suggest that HSP90ß may be a prospective target for the effective therapy of advanced hepatocellular carcinoma via accelerating apoptosis of hepatocellular carcinoma cells and eliciting mesenchymal-epithelial transition with the administration of Scutellaria baicalensis extract.

Pd-Catalyzed sequential hydroarylation and olefination reactions of 3-allylchromones.

In this paper, a novel approach to regioselective α- or γ-hydroarylation of 3-allylchromones with electron-rich arenes has been presented. Results of this study indicated that the regioselectivity was dependent on the substituent at the γ-position of the allyl group. Hydrogen or alkyl substitution favored α-hydroarylation, whereas aryl substitution favored γ-hydroarylation. This methodology provides an efficient means to achieve the α- or γ-selective hydroarylation of 3-allylchromones. Application of α-hydroarylation to perform Pd-catalyzed one-pot sequential α-hydroarylation and π-chelation-assisted olefination has also been reported.

Synthesis of 3-(2-Olefinbenzyl)-4H-chromen-4-one through Cyclobenzylation and Catalytic C-H Bond Functionalization Using Palladium(II).

An efficient strategy for synthesizing 3-(2-olefinbenzyl)-4H-chromen-4-one in two steps was developed. The first step is a cyclobenzylation reaction between (E)-3-(dimethylamino)-1-(2-hydroxyphenyl)prop-2-en-1-one and benzyl bromide to produce homoisoflavonoid. The second step involves intermolecular Pd-catalyzed π-chelating-assisted C-H bond olefination. Using the C-2/C-3 double bond of chromone, palladium-catalyzed aryl C-H bond activation can be functionalized to generate ortho-olefination derivatives in moderate to high yields.

Synthesis of (E)-oxindolylidene acetate using tandem palladium-catalyzed Heck and alkoxycarbonylation reactions.

Tandem reactions use consecutive reaction steps to efficiently synthesize compounds of high molecular complexity. This paper presents a tandem Pd-catalyzed Heck and alkoxycarbonylation reaction for the stereoselective synthesis of (E)-oxindolylidene acetates. The mechanism underlying the Pd-catalyzed tandem reaction involves the syn-carbopalladation of ynamides followed by alkoxycarbonylation with CO and alcohol. This method makes it possible to obtain the desired (E)-configuration of oxindolylidene acetates exclusively. We evaluated the scope of the reaction by applying optimal reaction conditions to the facile synthesis of a library of (E)-oxindolylidene acetates. The resulting (E)-oxindolylidene acetates exhibited potent anticancer activities against a variety of human cancer cell lines. The anticancer activities of some (E)-oxindolylidene acetates were even superior to those of known CDK inhibitors indirubin-3'-oxime and roscovitine.

The immunologically active oligosaccharides isolated from wheatgrass modulate monocytes via Toll-like receptor-2 signaling.

Wheatgrass is one of the most widely used health foods, but its functional components and mechanisms remain unexplored. Herein, wheatgrass-derived oligosaccharides (WG-PS3) were isolated and found to induce CD69 and Th1 cytokine expression in human peripheral blood mononuclear cells. In particular, WG-PS3 directly activated the purified monocytes by inducing the expression of CD69, CD80, CD86, IL-12, and TNF-α but affected NK and T cells only in the presence of monocytes. After further purification and structural analysis, maltoheptaose was identified from WG-PS3 as an immunomodulator. Maltoheptaose activated monocytes via Toll-like receptor 2 (TLR-2) signaling, as discovered by pretreatment of blocking antibodies against Toll-like receptors (TLRs) and also determined by click chemistry. This study is the first to reveal the immunostimulatory component of wheatgrass with well defined molecular structures and mechanisms.

BPR0C305, an orally active microtubule-disrupting anticancer agent.

BPR0C305 is a novel N-substituted indolyl glyoxylamide previously reported with in-vitro cytotoxic activity against a panel of human cancer cells including P-gp-expressing multiple drug-resistant cell sublines. The present study further examined the underlying molecular mechanism of anticancer action and evaluated the in-vivo antitumor activities of BPR0C305. BPR0C305 is a novel synthetic small indole derivative that demonstrates in-vitro activities against human cancer cell growth by inhibiting tubulin polymerization, disrupting cellular microtubule assembly, and causing cell cycle arrest at the G2/M phase. It is also orally active against leukemia and solid tumor growths in mouse models. Findings of these pharmacological and pharmacokinetic studies suggest that BPR0C305 is a promising lead compound for further preclinical developments.

Palladium-Catalyzed Cascade Endo-dig Cycloisomerization and Olefination with Alkenes to Access Fused Oxatricyclic Compounds.

A novel cascade Pd(II)-catalyzed endo-dig cycloisomerization and olefination reaction of 2-benzyl-3-alkynyl chromones with activated/unactivated alkenes has been developed for the synthesis of fused oxatricyclic compounds. This concise one-pot synthetic approach was applied to the difunctionalization of unbiased alkynes based on 2-benzyl-3-(alkynyl)-4H-chromen-4-one via O-attack endo-dig cycloisomerization, followed by olefination with both activated and unactivated alkenes.

Synthesis and biological evaluation of 2-amino-1-thiazolyl imidazoles as orally active anticancer agents.

Designed from a high throughput screened hit compound, novel 2-amino-1-thiazolyl imidazoles were synthesized and demonstrated cytotoxicity against human cancer cells. 1-(4-Phenylthiazol-2-yl)-4-(thiophen-2-yl)-1H-imidazol-2-amine (compound 2), a 2-amino-1-thiazolyl imidazole, inhibited tubulin polymerization, interacted with the colchicine-binding sites of tubulins, and caused cell cycle arrest at the G(2)/M phase in human gastric cancer cells. Disruption of the microtubule structure in cancer cells by compound 2 was also observed. Compound 2 concentration-dependently inhibited the proliferation of cancer cells in histocultured human gastric and colorectal tumors. Given orally, compound 2 prolonged the lifespans of leukemia mice intraperitoneally inoculated with the murine P388 leukemic cells. We report 2-amino-1-thiazolyl imidazoles as a novel class of orally active microtubule-destabilizing anticancer agents.

Palladium-Catalyzed Chemo- and Regiocontrolled Tandem Cyclization/Cross-Coupling of 2-Benzyl-3-alkynyl Chromones with Aryl Iodides for the Synthesis of 4H-Furo[3,2-c]chromenes and Xanthones.

A novel Pd-catalyzed chemo- and regiocontrolled tandem cyclization/cross-coupling reaction of 3-alkynyl chromone with aryl iodide was developed for the synthesis of 4H-furo[3,2-c]chromenes and xanthones. The difunctionalization of alkynes through O-attack/5-exo-dig and C-attack/6-endo-dig cyclization was reported by this rare approach, which was selectively controlled by the addition of KF or a bidentate phosphine ligand. A one-pot tandem process was demonstrated directly from γ-alkynyl-1,3-diketone for this method.

Therapeutic efficacy of Scutellaria baicalensis Georgi against psoriasis-like lesions via regulating the responses of keratinocyte and macrophage.

Psoriasis is a chronic and recurrent skin problem that affects 3% of the global population. Nowadays, most medicines may not promise a complete cure for patients with psoriasis because of the development of pharmacoresistance and the side effects of drugs due to the microenvironment impact in the context of skin imbalance. Herein, we attempt to explore the pharmaceutical efficacy of Scutellaria baicalensis (S. baicalensis) in modulating the microenvironment created by macrophages and keratinocytes in psoriasis. The results indicated that treatment of S. baicalensis extract significantly reduced the thickness of epidermis and attenuated psoriatic lesions. Moreover, S. baicalensis extract obviously inhibited the activation and infiltration of macrophages by alleviating inflammatory factors such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and cyclooxygenase-2 (COX-2). The administration of S. baicalensis extract also remarkably abolished oxidative damage upon DNA and proteins, which attributed to the activation of nuclear factor erythroid 2-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1). The network analysis of redox proteomics and cytokine profiles suggested that S. baicalensis administration regulated the specific pathways associated with oxidative stress, inflammation and cytokine signaling cascades to ameliorate the macrophage-targeted responses and subsequently arrest proliferation of keratinocytes. Collectively, our findings highlighted the importance of S. baicalensis application in reprogramming microenvironment to provide an alternative and complementary intervention for long-term psoriatic therapy.

BPR0C261 is a novel orally active antitumor agent with antimitotic and anti-angiogenic activities.

BPR0C261 is a synthetic small molecule compound cytotoxic against human cancer cells and active prolonging the lifespan of leukemia mice. In the present study, we further investigated the mechanisms of its anticancer action and found that BPR0C261 inhibited microtubule polymerization through interacting with the colchicine binding sites on tubulins, disrupted microtubule arrangement and caused cell cycle arrest at G(2)/M phase in cancer cells. BPR0C261 also inhibited the clonogenic growths of cancer cells and showed cytotoxicity against human cervical cancer cells of multidrug-resistant phenotype. In addition, BPR0C261 concentration-dependently inhibited the proliferation and migration of HUVECs and disrupted the endothelial capillary-like tube formations in HUVEC and rat aorta ring cultures. Given orally, BPR0C261 inhibited angiogenesis in s.c. implanted Matrigel plugs in mice. Notably, its IC(50) values against the endothelial cell growths were approximately 10-fold lower than those against the cancer cells. It was found orally absorbable in mice and showed a good oral bioavailability (43%) in dogs. BPR0C261 permeated through the human intestinal Caco-2 cell monolayer, suggesting oral availability in humans. Orally absorbed BPR0C261 distributed readily into the s.c. xenografted tumors in nude mice in which the tumor tissue levels of BPR0C261 were found oral dose-dependent. BPR0C261 showed in vivo activities against human colorectal, gastric, and nasopharyngeal tumors in nude mice. Most interestingly, the combination of BPR0C261 plus cisplatin synergistically prolonged the lifespans of mice inoculated with murine leukemia cells. Thus, BPR0C261 is a novel orally active tubulin-binding antitumor agent with antimitotic, apoptosis-inducing, and vasculature disrupting activities.

Pd-Catalyzed and ligand-enabled alkene difunctionalization via unactivated C-H bond functionalization.

Palladium-catalyzed and ligand-enabled C-H functionalization methods have emerged as a powerful approach for the preparation of therapeutically important motifs and complex natural products. Olefins, owing to their natural abundance, have been extensively employed for the formation of C-C and C-X bonds and the generation of various heterocycles. Traditionally, activated as well as starting materials with preinstalled functional groups, and also halide substrates under transition metal catalysis, have been employed for olefin difunctionalization. However, strategies for employing unactivated C-H bond functionalization to achieve alkene difunctionalization have rarely been explored. A possible solution to this challenge is the application of bulky ligands which enhances the reductive elimination pathway and inhibits ß-hydride elimination to selectively yield difunctionalized alkene products. This feature article summarizes the utilization of unreactive C-H bonds in the Pd-catalyzed and ligand-enabled difunctionalization of alkenes.

Influence of Chymosin on Physicochemical and Hydrolysis Characteristics of Casein Micelles and Individual Caseins.

The effects of chymosin on the physicochemical and hydrolysis characteristics of casein micelles and individual caseins were investigated. Adding 0.03 units of chymosin/mL led to the casein micelles in skim milk coagulating after a 3 h incubation period at 30 °C. SDS-PAGE investigation showed that ß-CN, κ-CN, αs-CN, and a portion of ß-lactoglobulin (ß-LG) in the milk supernatant fraction (MSF) were precipitated into the milk pellet fraction (MPF). The mean particle size of the MSF with chymosin decreased from 254.4 nm to 179.2 nm after a 3 h incubation period. Mass spectrometry and SDS-PAGE analysis suggested that chymosin hydrolyzed individual ß-CN, κ-CN, and αs-CN, but not ß-LG. Chymosin hydrolysis led to a decrease in the molecular weights of the hydrolyzed ß-CN, κ-CN, and αs-CN. Particle size analysis indicated that there was no difference in the particle size distribution of hydrolyzed ß-CN and αs-CN. Moreover, our outcomes demonstrated that the hydrolysis of κ-CN by chymosin occurs before that of ß-CN and αs-CN.

Antioxidant properties of red raspberry extract alleviate hepatic fibrosis via inducing apoptosis and transdifferentiation of activated hepatic stellate cells.

Hepatic fibrosis is a wound-healing process caused by prolonged liver damage and often occurs due to hepatic stellate cell activation in response to reactive oxygen species (ROS). Red raspberry has been found to attenuate oxidative stress, mainly because it is rich in bioactive components. In the current study, we investigated the inhibitory effects and associated molecular mechanisms of red raspberry extract (RBE) upon activated hepatic stellate cell (aHSC) in cellular and rat models. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were increased in the dimethylnitrosamine (DMN)-applied samples, whereas treatment of RBE significantly suppressed the activities of these enzymes. In addition, a histopathological analysis demonstrated that RBE could substantially diminish the hepatic collagen content and alpha-smooth muscle actin (α-SMA) expression induced by DMN. Administration of 250 µg/mL RBE could also arrest the growth and enhance the apoptosis of activated HSC-T6 cells, which was accompanied with elevated levels of activated caspases and poly (ADP-ribose) polymerase (PARP) cleavage. Particularly, RBE application remarkably abolished oxidative damage within the cells and reduced the carbonylation of proteins, which was attributed to the upregulation of catalase, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1). Moreover, the knockdown of Nrf2 together with the RBE treatment synergistically abrogated the expression of α-SMA and promoted the level of peroxisome proliferator-activated receptor gamma (PPAR-γ), suggesting that RBE could mitigate the transdifferentiation of HSC in a Nrf2-independent manner. These findings implied that the application of RBE could effectively remove oxidative stress and relieve the activation of HSC via modulating the caspase/PARP, Nrf2/HO-1 and PPAR-γ pathways, which may allow the development of novel therapeutic strategies against chemical-caused liver fibrogenesis.

Characterization of Maltase and Sucrase Inhibitory Constituents from Rhodiola crenulata.

The inhibitory properties of epicatechin-(4ß,8)-epicatechingallate (B2-3'-O-gallate), epicatechin gallate (ECG), and epicatechin (EC) isolated from Rhodiola crenulata toward maltase and sucrase were investigated. The half-maximal inhibitory concentration (IC50) values for maltase were as follows: B2-3'-O-gallate (1.73 ± 1.37 µM), ECG (3.64 ± 2.99 µM), and EC (6.25 ± 1.84 µM). Inhibition kinetic assays revealed the inhibition constants (Ki) of the mixed-competitive inhibitors of maltase, as follows: B2-3'-O-gallate (1.99 ± 0.02 µM), ECG (3.14 ± 0.04 µM), and EC (7.02 ± 0.26 µM). These compounds also showed a strong inhibitory activity toward sucrase, and the IC50 values of B2-3'-O-gallate, ECG, and EC were 6.91 ± 3.41, 18.27 ± 3.99, and 18.91 ± 3.66 µM, respectively. Inhibition kinetic assays revealed the inhibition constants (Ki) of the mixed-competitive inhibitors of sucrase as follows: B2-3'-O-gallate (6.05 ± 0.04 µM), ECG (8.58 ± 0.08 µM), and EC (13.72 ± 0.15 µM). Overall, these results suggest that B2-3'-O-gallate, ECG, and EC are potent maltase and sucrase inhibitors.

Red Raspberry Extract Protects the Skin against UVB-Induced Damage with Antioxidative and Anti-inflammatory Properties.

Extensive exposure to UVB (280-320 nm) is the major risk responsible for various skin injuries. Numerous reports have shown that natural products could demonstrate photochemopreventive efficacy against UVB damage. We investigated the preventive effects and associated molecular mechanisms of red raspberry extract upon UVB-caused damage in human epidermal keratinocytes and a nude mouse model. The protein profiles and immunohistological study on a nude mouse skin indicated that red raspberry extract could prevent UVB-caused cell death and protect the skin against UVB-exposed injury manifested by wrinkling, scaling, tanning, and water loss as well as epidermal thickening. In addition, red raspberry extract application effectively abolished oxidative damage in DNA and attenuated the carbonylation level of proteins, which attributed to the activation of SOD, Nrf2 and its target genes, and HO-1. Red raspberry extract also altered the cells' apoptotic signaling pathways including caspase-3 as well as the inflammatory cascade such as c-jun and attenuated UVB-induced activation of NF-κB and COX-2. Red raspberry extract could alleviate direct photodamage to the skin caused by UVB exposure through the ROS scavenger and protection against inflammatory responses, which may allow the development of novel strategies in protecting the skin subjected to UVB radiation.

Synthesis of 2-substituted 9-oxa-guanines {5-aminooxazolo[5,4-d]pyrimidin-7(6H)-ones} and 9-oxa-2-thio-xanthines {5-mercaptooxazolo[5,4-d]pyrimidin-7(6H)-ones}.

Oxazolo[5,4-d]pyrimidines can be considered as 9-oxa-purine analogs of naturally occurring nucleic acid bases. Interest in this ring system has increased due to recent reports of biologically active derivatives. In particular, 5-aminooxazolo[5,4-d]pyrimidine-7(6H)-ones (9-oxa-guanines) have been shown to inhibit ricin. The preparation of a series of 2-substituted 5-aminooxazolo[5,4-d]pyrimidin-7(6H)-ones and related 5-thio-oxazolo[5,4-d]pyrimidines is described, including analogs suitable for further elaboration employing "click" chemistry utilizing copper-catalyzed Huisgen 1,3-dipolar cycloadditions. Two of the compounds prepared were found to inhibit ricin with IC(50)ca. 1-3 mM.

Neuroprotective and Antineuroinflammatory Effects of Hydroxyl-Functionalized Stilbenes and 2-Arylbenzo[b]furans.

The drugs currently used to treat Alzheimer's disease (AD) are limited in the benefits they confer, and no medication has been clearly proven to cure or delay the progression of AD. Most candidate AD drugs are meant to reduce the production, aggregation, and toxicity of amyloid ß (Aß) or to promote Aß clearance. Herein, we demonstrate the efficient synthesis of hydroxyl-functionalized stilbene and 2-arylbenzo[b]furan derivatives and report on the neuroprotective and anti-inflammatory effects of these phenolic compounds in vitro and in an animal model. Structure-activity relationships revealed that the presence of an acrylate group on 2-arylbenzo[b]furan confers neuroprotective and anti-inflammatory effects. Furthermore, compounds 11 and 37 in this study showed particular potential for development as disease-modifying anti-Alzheimer's drugs, based on their neuroprotective effects on neuron cells, their antineuroinflammatory effects on glial cells, and the ability to ameliorate nesting behavior in APP/PS1 mice. These results indicate that 2-arylbenzo[b]furans could be candidate compounds for the treatment of AD.

Aggregation of soy protein-isoflavone complexes and gel formation induced by glucono-δ-lactone in soymilk.

This study investigated the glucono-δ-lactone (GDL)-induced aggregation of isoflavones and soy proteins in soymilk. High-performance liquid chromatography (HPLC) analysis indicated that isoflavones mixed with ß-conglycinin (7S) and glycinin (11S) proteins formed 7S-isoflavone and 11S-isoflavone complexes in soymilk supernatant fraction (SSF). Most of the soy protein-isoflavone complexes then precipitated into the soymilk pellet fraction (SPF) following the addition of 4 mM GDL, whereupon the pH value of the soymilk dropped from 6.6 to 5.9. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and HPLC analysis suggest that the addition of 4 mM GDL induced the aggregation of most 7S (α', α and ß subunits), 11S acidic and 11S basic proteins as well as isoflavones, including most aglycones, including daidzein, glycitein, genistein and a portion of glucosides, including daidzin, glycitin, genistin, malonyldaidzin and malonylgenistin. These results provide an important reference pertaining to the effects of GDL on the aggregation of soy protein-isoflavone complexes and could benefit future research regarding the production of tofu from soymilk.