Protection of prenylated flavonoids from Mori Cortex Radicis (Moraceae) against nitric oxide-induced cell death in neuroblastoma SH-SY5Y cells.

Seven prenylated flavanoids, licoflavone C (1), cyclomulberrin (2), neocyclomorusin (3), sanggenon I (4), morusin (5), kuwanon U (6) and kuwanon E (7), and three 2-arylbenzofurans, moracin P (8), moracin O (9), and mulberrofuran Q (10) were isolated from the MeOH extract of Mori Cortex Radicis. Among these, compounds 2-7 enhanced cell viability in a dose-dependent manner against sodium nitroprusside-induced cell death in neuroblastoma SH-SY5Y cells, which was measured by MTT reduction assay (EC(50) values of 4.4, 5.6, 8.0, 6.4, 8.7, and 11.9 µg/mL, respectively). Among 10 compounds, C-3 prenylated flavones (2, 3, and 5) and prenylated flavanones (4, 6, and 7) showed cell protection. However, compound 1 which lacks the prenyl group at C-3 and three 2-arylbenzofurans (8-10) did not show protective effect. The order of cell protection was as follow: C-3 prenylated flavones (2, 3, and 5) > prenylated flavanones (4, 6, and 7) > 2-arylbenzofurans (8-10) and flavone (1). From this result, we show that some prenylated flavones and flavanones might protect neuronal cells against nitrosative stress-mediated cell death. Even though further evaluations are necessary in vitro and in vivo study, we carefully suggest that some prenylated flavonoids from Mori Cortex Radicis might protect neuronal cells from neurodegenerative diseases.

Inhibitory effect of 2-arylbenzofurans from the Mori Cortex Radicis (Moraceae) on oxygen glucose deprivation (OGD)-induced cell death of SH-SY5Y cells.

Three known 2-arylbenzofurans, moracin P (1), moracin O (2) and mulberrofuran Q (3) were isolated from the MeOH extract of the Mori Cortex Radicis. These compounds 1-3 enhanced cell viability in dose-dependent manner against oxygen-glucose deprivation (OGD)-induced cell death in neuroblastoma SH-SY5Y cells, which was measured by MTT reduction assay. (EC(50) values of 10.4, 12.6, and 15.9 µM, respectively). In addition, the compounds 1-3 were examined for their inhibitory effect on OGD-induced ROS production by FACS analysis. We observed these compounds reduced ROS production in OGD-induced cell death (IC(50) values of 1.9, 0.3 and 12.1 µM, respectively). Consequently, reactive oxygen species (ROS) were overexpressed in OGD-induced cells and all three compounds reduced ROS induced by OGD in dosedependent manner. Taken together, compounds 1-3 might protect neuronal cell death against the oxidative stress induced by OGD, though further studies in vitro and in vivo models are necessary.

Neuroprotective effects of 3α-acetoxyeudesma-1,4(15),11(13)-trien-12,6α-olide against dopamine-induced apoptosis in the human neuroblastoma SH-SY5Y cell line.

Dopamine (DA), as a neurotoxin, can elicit severe Parkinson's disease-like syndrome by elevating intracellular reactive oxygen species (ROS) levels and apoptotic activity. We examined the inhibitory effects of 3α-acetoxyeudesma-1,4(15),11(13)-trien-12,6α-olide (AETO), purified from the leaves of Laurus nobilis L., on DA-induced apoptosis and α-synuclein (α-syn) formation in dopaminergic SH-SY5Y cells. AETO decreased the active form of caspase-3 and the levels of p53, which were accompanied by increased levels of Bcl-2 in a dose-dependent manner. Flow cytometric and Western blot analysis showed that AETO significantly inhibited DA-induced apoptosis along with suppression of intracellular tyrosinase activity, ROS generation, quinoprotein, and α-syn formation (P < 0.01). These results indicate that AETO inhibited DA-induced apoptosis, which is closely related to the suppression of intracellular tyrosinase activity and the formation of α-syn, ROS, and quinoprotein in SH-SY5Y cells.

Inhibitory effects of costunolide isolated from Laurus nobilis on IgE-induced degranulation of mast cell-like RBL-2H3 cells and the growth of Y16 pro-B cells.

This study investigated the inhibitory effects of costunolide isolated from the leaves of Laurus nobilis L. (Lauraceae) on basophil-mediated allergic reactions and interleukin (IL)-5-mediated B cell growth. The effects of costunolide on ß-hexosaminidase (a key parameter of degranulation) release and IL-4 expression in rat basophilic leukemia (RBL-2H3) cells were determined by measuring ß-hexosaminidase activity and by semi-quantitative RT-PCR, respectively. The effects of costunolide on Y16 pro-B cell viability and growth were determined by 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT) assay. Costunolide was found significantly to inhibit ß-hexosaminidase activity (p < 0.01) and IL-4 transcription in RBL-2H3 cells in a dose-dependent manner. Its 50% inhibitory concentration (IC50 ) was 34 µM, while that of the positive control, ketotifen, was 24 µM (IL-4 mRNA transcription). Moreover, costunolide dose-dependently suppressed pro-B cell growth in IL-5-stimulated Y16 cells. These results provide evidence that costunolide stabilizes mast cells by inhibiting IgE-mediated degranulation and inhibits IL-5-stimulated B cell growth.

Spirafolide from bay leaf (Laurus nobilis) prevents dopamine-induced apoptosis by decreasing reactive oxygen species production in human neuroblastoma SH-SY5Y cells.

Reactive oxygen species (ROS) are important mediators in many neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. This study tested the neuroprotective effects of spirafolide, a compound purified from the leaves of Laurus nobilis L. (Lauraceae), against dopamine (DA)-induced apoptosis in human neuroblastoma SH-SY5Y cells. Following a 24-h exposure of cells to DA (final conc., 0.6 mM), we observed a marked increase in apoptosis, increased generation of ROS and decreased cell viability. Pretreatment of the cells for 24 h with spirafolide (0.4, 2, and 10 µM) before exposure to DA notably increased cell survival (p < 0.01) and lowered intracellular ROS levels (p < 0.01). These results indicate that spirafolide has neuroprotective effects against DA toxicity. These effects may contribute to the treatment of neurodegenerative diseases.

Amelioration of oxygen and glucose deprivation-induced neuronal death by chloroform fraction of bay leaves (Laurus nobilis).

The purpose of this study was to determine whether the Laurus nobilis chloroform fraction (LNCF) protects against cerebral ischemia neuronal damage. Human neuroblastoma SH-SY5Y cells and brain slices from rats were subjected to oxygen and glucose deprivation (OGD), followed by reoxgenation with and without LNCF. The viabilities of SH-SY5Y cells and brain slices from the rats were 58.5±4.9% and 79.7±5.9% in the group subjected to OGD, and 80.4±0.4% and 97.2±1.9% at 4 µg/ml of LNCF, respectively. LNCF also significantly inhibited death-associated protein kinase (DAPK) dephosphorylation. Pretreatment with LNCF at 4 mg/kg significantly decreased infarct size by 79% of vehicle control in the middle cerebral artery occlusion (MCAO) in vivo model. LNCF is a neuroprotective drug candidate against cerebral ischemia neuronal damage.

Nuclear factor kappaB-mediated down-regulation of adhesion molecules: possible mechanism for inhibitory activity of bigelovin against inflammatory monocytes adhesion to endothelial cells.

The flowers of Inula britannica L. var. chinensis (Rupr.) Reg. (Compositae) are used in traditional medicine to treat asthma, chronic bronchitis, and acute pleurisy in China and Korea. However, the pharmacological actions of Inula britannica L. var. chinensis on endothelial cells and inflammatory monocytes are not clear. In this study, we investigated whether bigelovin, a sesquiterpene lactone isolated from the flowers of Inula britannica L. var. chinensis, inhibits monocyte adhesion and adhesion molecule expression in brain endothelial cells. We measured tumor necrosis factor-alpha (TNF-alpha)-enhanced Raw264.7 monocyte binding to brain endothelial cells and the levels of cell adhesion molecules, including vascular adhesion molecule-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM-1), and endothelial-selectin (E-selectin) on the surface of brain endothelial cells. Bigelovin significantly inhibited these in a dose-dependent manner without affecting cell viability. Furthermore, bigelovin suppressed the nuclear factor kappaB (NF-kappaB) promoter-driven luciferase activity, NF-kappaB activation, and degradation of NF-kappaB inhibitor protein alpha (IkappaBalpha). These results indicate that bigelovin inhibits inflammatory monocyte adhesion to endothelial cells and the expression of VCAM-1, ICAM-1, and E-selectin by blocking IkappaBalpha degradation and NF-kappaB activation.

Enantioseparation of N-fluorenylmethoxycarbonyl alpha-amino acids on polysaccharide-derived chiral stationary phases by reverse mode liquid chromatography.

The enantioseparation of N-protected fluorenylmethoxycarbonyl (N-FMOC) alpha-amino acids was carried out on three polysaccharide-derived chiral stationary phases, such as cellulose tris(3,5-dimethylphenylcarbamate) (Chiralcel OD), amylose tris(3,5-dimethyl-phenylcarbamate) (Chiralpak AD) and cellulose tris(4-methylbenzoate) (Chiralcel OJ), and the influence of acetonitrile composition and pH of the eluents on the enantioseparation in reverse mode chromatography was examined. The best separation of the enantiomers was achieved with 40% acetonitrile in 50mM phosphate buffer at pH 2. However, increasing the composition of acetonitrile to 50% on Chiralcel OD yielded a considerable decrease of retention time with minimum loss of resolution. The elution order of N-FMOC alpha-amino acid enantiomers on Chiralcel OD and OJ were quite different, indicating that both phases could be used in a complementary manner for the separation of the enantiomers of N-FMOC alpha-amino acids. The positive relationship between the capacity factor of N-FMOC alpha-amino acids and the hydrophobicity of amino acids indicated that hydrophobicity plays an important role on the retention of the N-FMOC alpha-amino acids in the reverse mode.

Distribution of (-)-yatein in Cupressaceae family analysed by high performance liquid chromatography.

The method for the chiral analysis of (-)-yatein was developed and the distribution of this component in the plants of three genera like Juniperus, Thuja and Chamaecyparis belonging to Cupressaceae family was examined. The chiral analysis of (-)-yatein from the plants was carried out by high performance liquid chromatography on (R,R)-Whelk-O1 column using 81 v/v% methanol as mobile phase. The yatein content in the leaves of Juniperus was the highest in compare with that of the other two genera, providing the possibility of the chemical discrimination of the plants in Juniperus from the other plants in the Cupressaceae family. In general, the yatein content in the leaves was much higher than that in the twigs. This method could be applied for the quality control of (-)-yatein in the plants belonging to Cupressaceae family.

Inhibitors of 5alpha -reductase type I in LNCaP cells from the roots of Angelica koreana.

A prenylated coumarin, osthenol (1) and a sesquiterpene, bisabolangelone (2) have been isolated as active principles with 5alpha-reductase type I inhibitory effects in LNCaP cells from the roots of Angelica koreana Max. by bioassay-guided chromatographic fractionation. Osthenol exhibited a highly potent inhibitory activity on 5alpha-reductase type I in LNCaP cells with an IC50 value of 0.1 microg/ml, which is about 200 times more potent than the positive control, finasteride (IC50 = 19.8 microg/ml). Bisabolangelone also inhibited the activity of 5alpha-reductase type I in LNCaP cells (IC50 = 11.6 microg/ml), indicating that these compounds are possible candidates for the development of new drugs to treat human endocrine disorders associated with overproduction of DHT by 5 alpha-reductase type I. In addition, four compounds isooxypeucedanin, oxypeucedanin hydrate, oxypeucedanin and isoimperatorin were also isolated and found to be inactive in the 5alpha-reductase assay systems used in the present study.