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The effects of sedative peptide alkaloids from Zizyphus species on calmodulin- dependent protein kinase II were investigated. Protein kinase II activity was assayed on the basis of its ability to activate tryptophan 5-monooxygenase as its substrate in the presence of calmodulin. All thirteen alkaloids tested were stronger inhibitors than chlorpromazine (IC50, 98 microM) on calmodulin-dependent protein kinase II. Among them, the most potent inhibitor was daechuine S27 (IC50 2.95 microM), which was stronger than pimozide (IC50, 15.0 microM).

A new neolignan, named simplidin was isolated from the the n-butanol extract of stem of Firmiana simplex, together with six known compounds, scopoletin (1), syrigaresinol (2), aquillochin (3), nitidanin (4), tamarixetin 3-rhamnoside (6), and quercitrin (7). On the basis of spectral and chemical evidence, simplidin (5) was determined to be rel-(7R,8R)-4,5,9,9'-tetrahydroxy-3,3'-dimethoxy-7-O-5',8-O-4'-neolignan. All the six compounds were also isolated for the first time from this plant.

Tissue factor (TF, tissue thromboplastin) is a membrane bound glycoprotein, which accelerates the blood clotting, activating both the intrinsic and the extrinsic pathways to serve as a cofactor for activated factor VII (VIIa). The TF-factor VIIa complex (TF/VIIa) proteolytically activates factors IX and X, which leads to the generation of thrombin and fibrin clots. In order to isolate TF inhibitors, by means of a bioassay-directed chromatographic separation technique, from the leaves of Eriobotrya japonica Lindley (Rosaceae), a known sesquiterpene glycoside (2) and ferulic acid (3) were isolated as inhibitors that were evaluated using a single-clotting assay method for determining TF activity. Another sesquiterpene glycoside (1) was also isolated but was inactive in the assay system. Compound 3 was yielded by alkaline hydrolysis of compound 2. The structures of compounds 1, 2, and 3 were identified by means of spectral analysis as 3-O-alpha-L-rhamnopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->6)]-beta-D-glucopyranosyl nerolidol (1), 3-O-alpha-L-rhamnopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-(4-trans-feruloyl)-rhamnopyranosyl-(1-->6)]-beta-D-glucopyranosyl nerolidol (2) and ferulic acid (3), respectively. Compounds 2 and 3 inhibited 50% of the TF activity at concentrations of 2 and 369 microM/TF units, respectively.

Tissue factor (TF, tissue thromboplastin or coagulation factor III) accelerates the blood clotting, activating both the intrinsic and the extrinsic pathways to serve as a cofactor. In order to isolate TF inhibitors from the fruits of Chaenomeles sinensis, an activity-guided purification utilizing a bio-assay method of prothrombin time prolongation, was carried out to yield five active flavoniods such as hovetrichoside C (1) (IC50 = 14.0 microg), luteolin-7-O-beta-D-glucuronide (3) (IC50 = 31.9 microg), hyperin (4) (IC50 = 20.8 microg), avicularin (6) (IC50 = 54.8 microg) and quercitrin (10) (IC50 = 135.7 microg), along with other inactive compounds such as (+/-)-(2E,4E-O-beta-D-glucopyranosyl-4'-hydroxy-beta-ionylideneacetic acid ester (2), genistein-7-O-beta-D-glucopyranoside (5), luteolin-3'-methoxy-4'-O-beta-D-glucopyranoside (7), luteolin-7-O-beta-D-glucuronide methyl ester (8), tricetin-3'-methoxy-4'-O-beta-D-glucopyranoside (selagin-4'-O-beta-D-glucopyranoside) (9), (-)-epicatechin (11), luteolin-4'-O-beta-D-glucopyranoside (12) and apigenin-7-O-beta-D-glucuronide methyl ester (13). The structures of the isolated compounds were elucidated through spectral analysis. Among them, compounds 1 to 9,12 and 13 were isolated for the first time from the fruits of this plant and the compound 9 is a new flavonoid.

Hepatic lipid peroxide contents were examined in bromobenzene-treated rats firstly after the oral administration of MeOH extract of Kalopanax pictus stem barks, its n-BuOH fraction, EtOAc fraction and an alkaline hydrolysate of the n-BuOH fraction, and secondly after the intraperitoneal administration of hederagenin monodesmosides and bisdesmosides. Two hederagenin monodesmosides, kalopanaxsaponin A (KPS-A) and sapindoside C, exhibited significant anti-lipid peroxidation effects after intraperitoneal administration at doses of 10-30 micromole/kg, whereas their bisdesmosides did not exhibit any significant activity. These results suggest that it is the hederagenin monodesmosides that are responsible for anti-lipid peroxidation in vivo. The activity of KPS-A was established by the observation of decreased aminopyrine N-demethylase activity and increased epoxide hydrolase activity.

In a course of obtaining more amount of bioactive costunolide and successive phytochemical isolation from Magnolia sieboldii (Magnoliaceae), a novel acyclic monoterpene 1 named deoxygeraniol [2,6(E)-dimethyl-2,6-octadiene] was isolated along with beta-sitosterol 3-O-linoleate (2), trilinolein (3) and high amount of costunolide (4) in the pure state. The structure of compound 1 was determined on the basis of spectroscopic data. Costunolide was found to induce apoptotic cell death in a dose-dependent manner by nucleosomal DNA ladder and flow cytometric analysis. Immunoblot analysis showed that the level of the anti-apoptotic protein, Bcl-2, was decreased, whereas the cleavage of poly-(ADP-ribose) polymerase was activated. Furthermore, the N-acetyl-L-cysteine antioxidant effectively prevented costunolide-induced cytotoxicity. These results suggest that costunolide-induced cell death is mediated by reactive oxygen species

The effects of various sedative cyclopeptides and peptide alkaloids from the Zizyphus species on calmodulin-dependent Ca2+-ATPase and phosphodiesterase were investigated. Calmodulin-induced activation of Ca2+-ATPase was strongly inhibited by sanjoinine-A dialdehyde (IC0O, 2.3 microM), -Ah1 (IC50, 4.0 microM), -A (IC50, 4.6 microM), and -G2 (IC50, 7.2 microM), while calmodulin-induced activation of phosphodiesterase was strongly inhibited by both deachuine-S10 (IC30, 4.9 microM) and sanjoinine-D (IC50, 9.0 microM). The inhibitory activity of the various cyclopeptides and peptide alkaloids on Ca2+-ATPase was found to correlate well with their sedative activity.

Three varieties of methyl citrate and 1-methyl malate were isolated from the fruits of Opuntia ficus-indica var. saboten Makino through in vitro bioassay-guided isolation for the inhibition on monoamine oxidase(MAO). The IC50 values for MAO-B of 1-monomethyl citrate, 1,3-dimethyl citrate, trimethyl citrate and 1-methyl malate were 0.19, 0.23, 0.61 and 0.25 mM, respectively. However, on MAO-A, their inhibitions showed only marginal activity.

Tissue factor (TF), a principal initiator of the vertebrate coagulation cascade, is expressed in organ tissues, cells and blood. TF is known to be induced in endothelial cells, monocytes and macrophages by inflammatory stimuli and in many pathologic conditions. By using the modified method for in vivo TF activity assay, we found that turpentine oil injection as an inflammatory stimulus also induced the TF activity in lung and brain tissues of rats. And the age-related increase in TF activity was observed in healthy rat brain tissue.

In activated macrophages the inducible form of nitric oxide synthase (i-NOS) generates high amounts of toxic mediator, nitric oxide (NO) which contributes to the circulatory failure associated with septic shock. A sesquiterpene lactone compound (yomogin) isolated from medicinal plant Artemisia princeps Pampan inhibited the production of NO in LPS-activated RAW 264.7 cells by suppressing i-NOS enzyme expression. Thus, yomogin may be a useful candidate for the development of new drugs to treat endotoxemia and inflammation accompanied by the overproduction of NO.

To search for the anti-diabetic principle from the stem bark of Kalopanax pictus, seven kinds of chemical constituents including hedearagenin glycosides and phenolic glycosides were isolated. The anti-diabetic evaluation of these isolates in the streptozotocin-induced diabetic rats exhibited that kalopanaxsaponin A has a potent anti-diabetic activity in contrast to a mild activity of hedearagenin. In addition, significant hypocholesterolemic and hypolipidemic activities of kalopanaxsaponin A and hedearagenin were observed. The structure-activity relationship of kalopanaxsaponin A was also investigated in the present work.

A new celastraceae alkaloid, euojaponine C has been isolated from the methanol extract of the root bark ofEuonymus japonica. With the relative stereochemistry of euojaponine C established by NOESY data, the absolute stereochemistry has been determined by circular dichroism (CD) exciton chirality method. The CD of the 2, 5-bis-phenyl benzoate of triacetonide derived from the LiAlH(4) hydrolysate, euonyminol shows that the configuration of C-2 and C-5 are both R.