Extracts of Musa basjoo induce growth inhibition and changes in the protein expression of cell cycle control molecules in human colorectal cancer cell lines.

Musa basjoo (MB) is a species of the banana plant belonging to the genus Musa that has been used as a folk medicine. However, evidence-based biological activities and the molecular mechanism of action of MB are unknown. Thus, the aim of the present study was to examine whether the crude dried leaf extracts of MB inhibit the growth of colorectal (HT29 and HCT116) and other types (HepG2, MCF-7 and PC-3) of human cancer cell lines. Crude extracts of MB inhibited the growth of cells with IC50 values of 136 µg/ml (acetone extract, HT29), 51 µg/ml (acetone extract, HCT116), 45 µg/ml (acetone extract, HepG2), 40 µg/ml (acetone extract, MCF-7), 29 µg/ml (acetone extract, PC-3), 175 µg/ml (methanol extract, HT29), 137 µg/ml (methanol extract, HCT116), 102 µg/ml (methanol extract, HepG2), 85 µg/ml (methanol extract, MCF-7), and 85 µg/ml (methanol extract, PC-3) in colony formation assays, and 126 µg/ml (acetone extract, HT29), 68 µg/ml (acetone extract, HCT116), 260 µg/ml (methanol extract, HT29), and 216 µg/ml (methanol extract, HCT116) in MTT assays. Thin layer chromatography analysis revealed the potential existence of aromatic compounds in the acetone extract of MB. Flow cytometric analysis indicated that the percentage of cells in G1 increased, and this was associated with a concomitant decrease of cells in the S and/or G2-M phases of the cell cycle. When colorectal cancer cells were treated with acetone extract of MB, there was a marked decrease in the levels of expression of the cyclin D1, cyclin E, cdk2 and cdk4 proteins and a marked increase in the levels of the expression of the p21CIP1, p27KIP1, and p53 proteins, but those of apoptosis-associated protein PARP did not change. There was a tendency for acetone extract of MB to inhibit xenograft tumor growth in mice. Collectively, the crude extracts of MB contain active components that exert growth inhibition of human cancer cells. This is the first systematic study of the anticancer activity of MB and may broaden insights into the possible clinical approach of specific herbal medicines.

Palmitoyl piperidinopiperidine, a novel derivative of 10­hydroxy­2­decenoic acid, as a potent and selective anticancer agent against human colon carcinoma cell lines.

The present study, to the best of our knowledge, is the first systematic study of the inhibitory effects of palmitoyl piperidinopiperidine (PPI; Japan Patent no. 5597427), on colon carcinogenesis. PPI exhibited marked growth inhibitory activity in several human colon carcinoma cell lines, with IC50 values of approximately 0.5­2.2 µM. In silico docking analysis indicated that PPI could bind to the SH2 domain of signal transducer and activator of transcription 3 (STAT3). PPI markedly inhibited the transcriptional activity of the SW837 cell line. Flowcytometric analysis demonstrated that PPI induced an increase in the number of cells in the G1 phase of the cell cycle, and induced sub­G1 fractions of cells at a higher concentration level of PPI. In the HT29 and SW837 cells, western blot analyses exhibited that in whole cell lysates, PPI induced a marked decrease in the expression levels of p­STAT3, but not in the levels of STAT3 in these cells. PPI also induced a marked decrease in the expression levels of both STAT3 and p­STAT3 in the chromatin fraction. In addition, PPI affected the protein expression levels of cyclin D1, p53, Bcl­2, Bcl­xL and vascular endothelial growth factor (VEGF). In the HT29 cells, PPI induced a marked and dose­dependent increase in the expression levels of Bax, cleaved caspase­3, cleaved caspase­7, cleaved caspase­8, cleaved caspase­9 and cleaved poly (ADP­ribose) polymerase (PARP). In animal model systems, PPI inhibited the growth of implanted carcinoma cells, and also induced a significant decrease in the multiplicity of colonic aberrant crypt foci. In addition, a marked and dose­dependent inhibition of angiogenesis of the chick chorioallantoic membrane was observed. As regards the possible molecular mechanisms, it is suggested that the inhibition of STAT3 by PPI may affect the function of molecules that are related to apoptosis, angiogenesis and cell cycle progression, eventually contributing to the PPI­induced growth inhibitory effects.

Crude α-Mangostin Suppresses the Development of Atherosclerotic Lesions in Apoe-Deficient Mice by a Possible M2 Macrophage-Mediated Mechanism.

Lifestyle choices play a significant role in the etiology of atherosclerosis. Male Apoe-/- mice that develop spontaneous atherosclerotic lesions were fed 0%, 0.3%, and 0.4% mangosteen extracts, composed largely of α-mangostin (MG), for 17 weeks. Body weight gains were significantly decreased in both MG-treated groups compared to the control, but the general condition remained good throughout the study. The levels of total cholesterol (decreased very-low-density lipoprotein in lipoprotein profile) and triglycerides decreased significantly in the MG-treated mice in conjunction with decreased hepatic HMG-CoA synthase and Fatty acid transporter. Additionally, increased serum lipoprotein lipase activity and histopathology further showed a significant reduction in atherosclerotic lesions at both levels of MG exposure. Real-time PCR analysis for macrophage indicators showed a significant elevation in the levels of Cd163, an M2 macrophage marker, in the lesions of mice receiving 0.4% MG. However, the levels of Nos2, associated with M1 macrophages, showed no change. In addition, quantitative immunohistochemical analysis of macrophage subtypes showed a tendency for increased M2 populations (CD68⁺/CD163⁺) in the lesions of mice given 0.4% MG. In further analysis of the cytokine-polarizing macrophage subtypes, the levels of Interleukin13 (Il13), associated with M2 polarization, were significantly elevated in lesions exposed to 0.4% MG. Thus, MG could suppress the development of atherosclerosis in Apoe-/- mice, possibly through an M2 macrophage-mediated mechanism.

Synthetic α-mangostin dilaurate strongly suppresses wide-spectrum organ metastasis in a mouse model of mammary cancer.

We previously reported that, in a mouse model of mammary cancer, α-mangostin alone exhibits anti-metastatic properties. To enhance this anti-metastatic effect, we examined the efficacy of synthetic α-mangostin dilaurate (MGD), prepared by adding lauric acid to α-mangostin, in the same experimental system wherein mice bearing mammary tumors are exposed to dietary MGD at 0, 2000 and 4000 ppm. Lauric acid has a high propensity for lymphatic absorption, which is the most common pathway of initial dissemination of many solid malignancies. Both mammary tumor volumes and wide-spectrum organ metastasis were markedly reduced at 2000 and 4000 ppm: furthermore, survival in the 4000-ppm group was significantly greater than in control mice. Apoptosis in mammary carcinomas was also significantly increased in the 4000-ppm group, whereas blood microvessel density and lymphatic vessel invasion were markedly reduced. In real-time PCR analyses of tumor samples, increased p21 and decreased Pcna expression were observed with 4000 ppm but values were not statistically significant when compared to expression in control tumors. However, exposure to 4000 ppm significantly decreased expression of phospho-Akt (Ser473/Thr308) as compared to the control, indicating a role in the anti-tumorigenic effects of MGD. These findings suggest that MGD may be useful for adjuvant therapy and chemoprevention and that conjugated medium-chain fatty acids may enhance the efficacy of certain chemotherapeutic agents.

Ikarisoside A inhibits acetylcholine-induced catecholamine secretion and synthesis by suppressing nicotinic acetylcholine receptor-ion channels in cultured bovine adrenal medullary cells.

Ikarisoside A is a natural flavonol glycoside derived from plants of the genus Epimedium, which have been used in Traditional Chinese Medicine as tonics, antirheumatics, and aphrodisiacs. Here, we report the effects of ikarisoside A and three other flavonol glycosides on catecholamine secretion and synthesis in cultured bovine adrenal medullary cells. We found that ikarisoside A (1-100 µM), but not icariin, epimedin C, or epimedoside A, concentration-dependently inhibited the secretion of catecholamines induced by acetylcholine, a physiological secretagogue and agonist of nicotinic acetylcholine receptors. Ikarisoside A had little effect on catecholamine secretion induced by veratridine and 56 mM K(+). Ikarisoside A (1-100 µM) also inhibited (22)Na(+) influx and (45)Ca(2+) influx induced by acetylcholine in a concentration-dependent manner similar to that of catecholamine secretion. In Xenopus oocytes expressing α3ß4 nicotinic acetylcholine receptors, ikarisoside A (0.1-100 µM) directly inhibited the current evoked by acetylcholine. It also suppressed (14)C-catecholamine synthesis and tyrosine hydroxylase activity induced by acetylcholine at 1-100 µM and 10-100 µM, respectively. The present findings suggest that ikarisoside A inhibits acetylcholine-induced catecholamine secretion and synthesis by suppression of nicotinic acetylcholine receptor-ion channels in bovine adrenal medullary cells.

Anti-Androgenic Activity of Icarisid II from Epimedium Herb in Prostate Cancer LNCaP Cells.

Anti-androgens are regarded as potential therapeutic agents for the treatment of prostate cancer. We determined that an epimedium herb (EH) extract exhibited anti-androgenic activity in a luciferase assay using androgen receptor-positive prostate cancer LNCaP cells. Nine EH-derived flavonoids were examined. The results identified icarisid II as a very potent anti-androgenic EH-derived flavonoid. A quantitative RT-PCR analysis confirmed that the flavonol suppressed the expression of the androgen-responsive KLK3 gene.

A novel 2-decenoic acid thioester ameliorates corticosterone-induced depression- and anxiety-like behaviors and normalizes reduced hippocampal signal transduction in treated mice.

We characterized mice administered corticosterone (CORT) at a dose of 20 mg/kg for 3 weeks to determine their suitability as a model of mood disorders and found that the time immobilized in the tail suspension test was longer and the time spent in the open arms of the elevated plus-maze test was shorter than those of the vehicle-treated group, findings demonstrating that chronic CORT induced both depression-like and anxiety-like behaviors. Furthermore, the levels of phosphorylated extracellular signal-regulated kinase (pERK) 1/2 in the hippocampus and cerebral cortex were reduced in the CORT-treated group. Using this model, we investigated the protective effect of the ester, thioester, and amide compounds of 2-decenoic acid derivatives (termed compounds A, B, and C, respectively). The potency of the protective activity against the CORT-induced depression-like or anxiety-like behaviors and the reduction in pERK1/2 level were found to be in the following order: compound B > compound C > compound A. Therefore, we further investigated the therapeutic activity of only compound B, and its effect on depression-like behavior was observed after oral administration for 1 or 2 weeks, and its effect on anxiety-like behavior was observed after oral administration for 3 weeks. The ratios of phosphorylated ERK1/2, Akt, and cAMP-response element-binding protein to their respective nonphosphorylated forms were smaller in the CORT-treated group than in the vehicle-treated group; however, subsequent treatment with compound B at either 0.3 or 1.5 mg/kg significantly ameliorated this reduction. Compound B appeared to elicit intracellular signaling, similar to that elicited by brain-derived neurotrophic factor, and its mode of action was shown to be novel and different from that of fluvoxamine, a currently prescribed drug for mood disorders.

Anti-androgenic activity of hydroxyxanthones in prostate cancer LNCaP cells.

Anti-androgens are used to treat prostate cancer. Here, we report that hydroxyxanthones from a plant extract act as anti-androgens in androgen receptor (AR)-positive prostate cancer LNCaP cells. Anti-androgenic activity of the ethanol extract from Garcinia subelliptica was observed in a luciferase assay using LNCaP/MMTV cells with a stably integrated mouse mammary tumor virus (MMTV) promoter. HPLC-based activity profiling followed by a chemical library-based assay strategy enabled the rapid identification of several active principles bearing a xanthone core substituted with hydroxyl and isoprenyl groups. Among the active compounds, 2-(1,1-dimethyl-allyl)-1,4,5,6-tetrahydroxyxanthone (subelliptenone F) was identified as a potent inhibitor of AR transcriptional activity. The structure-activity relationship of some substituents on the xanthone core was also determined using the chemical library-based bioassay. A quantitative RT-PCR analysis revealed that treatment with the compound resulted in a significant reduction in AR-induced gene (KLK3) expression. Hydroxyxanthone may be a possible candidate for the development of a new anti-androgenic molecule.

γ-Mangostin from Garcinia mangostana pericarps as a dual agonist that activates Both PPARα and PPARδ.

We tested the peroxisome proliferator-activated receptor (PPAR)δ agonistic activity of a Garcinia mangostana pericarp extract to develop a treatment for the metabolic syndrome, and demonstrated γ-mangostin to be an active compound on the basis of a luciferase reporter gene assay. γ-Mangostin induced the expression of the uncoupling protein-3 (UCP-3) gene which is related to energy expenditure and fat metabolism in L6 cells. We showed that γ-mangostin is a dual agonist that activates both PPARδ and PPARα. γ-Mangostin also induced the expression of acyl-CoA synthase and carnitine palmitoyl-transferase 1A genes in HepG2 cells. These results suggest the potential of γ-mangostin as a preventive agent of the metabolic syndrome.

Anxiolytic-like effect of trans-2-decenoic acid ethyl ester in stress-induced anxiety-like model mice.

Brain-derived neurotrophic factor (BDNF) is considered to be involved in the etiology and treatment of stress-related mood disorders including anxiety. However, application of BDNF itself has many technical and pharmacological problems such as instability and/or a lack of appropriate delivery systems. To overcome these, we developed trans-2-decenoic acid ethyl ester (DAEE) as a stable and small molecule with BDNF-like activities. In the present study, we tested the activities of DAEE on a stress-induced anxiety-like mouse model. Mice were kept in cages and subjected to 3 sets of sequential leaning, drenching, and rotation as chronic mild stresses applied for 1-2 days over a 3-week period; and the anxiety-like symptom (reduced time spent in open arm of the maze) was evaluated by use of the elevated plus-maze test. A daily intraperitoneal administration of DAEE competed against the expression of the anxiety-like symptom when administered during the stress-loading period, and became therapeutic when administered after the stress-loading. This activity was accompanied by amelioration of the stress-induced reduction in the levels of BDNF and neurotrophin-3 mRNAs and phosphorylated extracellular signal-regulated kinases (ERK) 1/2 in the hippocampus. These results demonstrated that DAEE behaved like an anxiolytic and ameliorated this characteristic anxiety-like symptom, suggesting that DAEE may be a promising candidate for a novel anxiolytic with a new mechanism of action.

Characterization of a glycyrrhizin-deficient strain of Glycyrrhiza uralensis.

A triterpene saponin, glucoglycyrrhizin, was isolated from a glycyrrhizin-deficient strain 83-555 of Glycyrrhiza uralensis (Leguminosae), and the structure was determined by chemical and spectral data to be 3-O-[ß-D-glucopyranosyl-(1→2)-ß-D-glucuronopyranosyl]-glycyrrhetinic acid. Since this saponin has a 2'-O-ß-D-glucopyranosyl moiety instead of the 2'-O-ß-D-glucuronopyranosyl moiety of glycyrrhizin, the glucuronidation of 3-O-ß-D-glucuronopyranosyl-glycyrrhetinic acid leading to glycyrrhizin is inhibited in this strain. All 4 offspring of the 83-555 strain produced glucoglycyrrhizin. Interestingly, 2 of the offspring produced both glycyrrhizin and glucoglycyrrhizin, and sequence analysis of the pkr gene suggested that these 2 offspring were hybrids of 83-555 strain and glycyrrhizin-producing strains.

Isolation of six isoprenylated biflavonoids from the leaves of Garcinia subelliptica.

The acetone-soluble parts of Garcinia subelliptica leaves were analyzed and six new biflavonoids were isolated, i.e., garciniaflavones A-F (1-6), as well as the five known biflavonoids amentoflavone (7), podocarpusflavone A (8), (+)-morelloflavone (9), (+)-morelloflavone-7"-O-ß-glucopyranoside (10), and (+)-4'''-O-methylmorelloflavone (11) and the three triterpenoids oleanan-3-one, ß-amyrin, and cycloartenol. The structures of the isolates were established based on spectroscopic analyses, including a detailed NMR spectroscopic investigation. The new biflavonoids are rare mono-isoprenylated derivatives that have a flavone-(3'-8")-flavone core (1-4: amentoflavone type) and a flavanone-(3-8")-flavone core (5, 6: morelloflavone type). The absolute configurations of the morelloflavone-type biflavonoids (5, 6) were confirmed by circular dichroism to be 2R,3S. The biflavonoids with an isoprenyloxy group (1) and a 2-hydroxy-3-methyl-3-butenyl group (2), and the morelloflavone-type biflavonoids with a C(5) unit are the first examples in nature. We found that 7, one of the major biflavonoids, strongly inhibited hypoxia-inducible factor-1 in human embryonic kidney 293 cells under hypoxic conditions.

A kavalactone derivative inhibits lipopolysaccharide-stimulated iNOS induction and NO production through activation of Nrf2 signaling in BV2 microglial cells.

Neuroinflammation and oxidative stress are involved in the pathogenesis of neurodegenerative diseases such as Alzheimer's diseases and Parkinson's disease. Naturally derived kavalactones isolated from Piper methysticum (Piperaceae) have been shown to exhibit neuroprotective effects. We have previously reported that a chemically synthesized kavalactone derivative, 2',6'-dichloro-5-methoxymethyl-5,6-dehydrokawain (compound 1) protects against oxidative stress-induced neuronal cell death through activation of Nrf2 signaling. In the present study, we examined the effect of compound 1 on neuroinflammation. In BV2 microglial cells, compound 1 strongly inhibited LPS-stimulated iNOS induction and NO production, but did not affect LPS-stimulated induction of COX2. At 6h after LPS challenge, when iNOS induction was not clearly seen, treatment with LPS or compound 1 alone increased expression of heme oxygenase 1 (HO-1) whose transcription is regulated by Nrf2. When treated with both, compound 1 enhanced LPS-stimulated HO-1 induction, which was more evident at 24h after LPS treatment. Furthermore, LPS-stimulated activation of Nrf2 signaling and nuclear translocation of Nrf2 were potentiated by compound 1. The mechanism by which compound 1 activated Nrf2 signaling was supposed to be a covalent modification of the sulfhydryl groups of Keap1 by an α,ß-unsaturated carbonyl group present in the compound 1. Treatment with hemin, a HO-1 inducer, and with [Ru(CO)3Cl2]2, a CO donor, decreased LPS-stimulated iNOS induction and NO production. In contrast, siRNA-mediated knockdown of HO-1 expression reduced the inhibitory effect of compound 1 on LPS-stimulated iNOS induction and NO production. The compound 1 inhibited LPS-stimulated ERK phosphorylation after LPS treatment. Finally, compound 1 suppressed LPS/IFN-γ-stimulated NO production in primary microglial cells. These results suggest that compound 1 is capable of inhibiting LPS-stimulated iNOS induction and NO production via activation of Nrf2 signaling and HO-1 induction in microglial cells. Taken together, compound 1 has a potential to reduce neuroinflammation as well as oxidative stress in neurodegenerative diseases through activation of Nrf2 signaling.

Anti-degranulating activity in rat basophil leukemia RBL-2H3 cells of flavanone glycosides and their aglycones in citrus fruits.

The anti-degranulating activity of flavonoids present in Citrus fruits was comprehensively evaluated. Among these, hesperetin and naringenin, respectively aglycones of hesperidin and narirutin, showed significant activity. The targets of hesperetin and naringenin were found: hesperetin inhibited phosphorylation of Syk and Akt, while naringenin suppressed the expression of Lyn and inhibited the phosphorylation of Akt. These results suggest that hesperetin and naringenin inhibit degranulation by suppression of pathway signals and reduce the symptoms of allergy by inhibiting phosphorylation of Akt, which leads to the suppression of cytokines. In addition, hesperetin showed inhibitory activity against the degranulation induced by calcium ionophores, indicating that hesperetin exerts its inhibitory activity by stabilizing the membrane structure.

New glycosides of acetophenone derivatives and phenylpropanoids from Juniperus occidentalis.

New glycosides of seven acetophenone derivatives (1-7) and two phenylpropanoids (8, 9), named juniperosides III-XI, have been isolated from the MeOH extract of the leaves and stems of Juniperus occidentalis Hook. (Cupressaceae), together with eleven other known compounds. The structures of these compounds have been successfully elucidated using a variety of spectroscopic techniques.

Characterization of rabbit morphine 6-dehydrogenase and two NAD(+)-dependent 3α(17ß)-hydroxysteroid dehydrogenases.

Mammalian morphine 6-dehydrogenase (M6DH)(1) converts morphine into a reactive electrophile, morphinone. M6DH belongs to the aldo-keto reductase (AKR) superfamily, but its endogenous substrates and entire amino acid sequence remain unknown. A recent rabbit genomic sequencing predicts three genes for novel AKRs (1C26, 1C27 and 1C28) that share >87% amino acid sequence identity and are similar to the partial sequence of rabbit liver M6DH. We isolated cDNAs for the three AKRs, and compared the properties of their recombinant enzymes. Like M6DH, only AKR1C26 that shares the highest sequence identity with hepatic M6DH oxidized morphine. The three AKRs showed NAD(+)-dependent dehydrogenase activity towards other non-steroidal alicyclic alcohols and 3α/17ß-hydroxy-C(18)/C(19)/C(21)-steroids, and their mRNAs were ubiquitously expressed in rabbit tissues. The kinetic constants for the substrates suggest that at least AKR1C26 and AKR1C28 act as NAD(+)-dependent 3α/17ß-hydroxysteroid dehydrogenases. AKR1C27 differed from AKR1C28 in its high K(m) values for the substrates and low sensitivity towards competitive inhibitors (ikarisoside A, hinokitiol, hexestrol and zearalenone), despite their 95% sequence identity. The site-directed mutagenesis of Tyr118 and Phe310 in AKR1C27 to the corresponding residues (Phe and Ile, respectively) in AKR1C28 produced an enzyme that was similar to AKR1C28, suggesting their key roles in ligand binding.

ATF6alpha promotes astroglial activation and neuronal survival in a chronic mouse model of Parkinson's disease.

Accumulating evidence suggests a crucial role for the unfolded protein response (UPR) in Parkinson's disease (PD). In this study, we investigated the relevance of the UPR in a mouse model of chronic MPTP/probenecid (MPTP/P) injection, which causes severe and persistent degeneration of dopaminergic neurons. Enhanced activation of the UPR branches, including ATF6α and PERK/eIF2α/ATF4, was observed after MPTP/P injections into mice. Deletion of the ATF6α gene accelerated neuronal degeneration and ubiquitin accumulation relatively early in the MPTP/P injection course. Surprisingly, astroglial activation was strongly suppressed, and production of the brain-derived neurotrophic factor (BDNF) and anti-oxidative genes, such as heme oxygenase-1 (HO-1) and xCT, in astrocytes were reduced in ATF6α -/- mice after MPTP/P injections. Decreased BDNF expression in ATF6α -/- mice was associated with decreased expression of GRP78, an ATF6α-dependent molecular chaperone in the ER. Decreased HO-1 and xCT levels were associated with decreased expression of the ATF4-dependent pro-apoptotic gene CHOP. Consistent with these results, administration of the UPR-activating reagent tangeretin (5,6,7,8,4'-pentamethoxyflavone; IN19) into mice enhanced the expression of UPR-target genes in both dopaminergic neurons and astrocytes, and promoted neuronal survival after MPTP/P injections. These results suggest that the UPR is activated in a mouse model of chronic MPTP/P injection, and contributes to the survival of nigrostriatal dopaminergic neurons, in part, through activated astrocytes.

Inhibition of human aldose reductase-like protein (AKR1B10) by α- and γ-mangostins, major components of pericarps of mangosteen.

A human member of the aldo-keto reductase (AKR) superfamily, AKR1B10, was recently identified as both diagnostic marker and therapeutic target in the treatment of several types of cancer. In this study, we have examined AKR1B10 inhibition by five xanthone derivatives, components of pericarps of mangosteen, of which α- and γ-mangostins show potential anti-cancer properties. Among the five xanthones, γ-mangostin was found to be the most potent competitive inhibitor (inhibition constant, 5.6 nM), but its 7-methoxy derivative, α-mangostin, was the second potent inhibitor (inhibition constant, 80 nM). Molecular docking of the two mangostins in AKR1B10 and site-directed mutagenesis of the putative binding residues revealed that Phe123, Trp220, Val301 and Gln303 are important for the tight binding of γ-mangostin, and suggested that the 7-methoxy group of α-mangostin impairs the inhibitory potency by altering the orientation of the inhibitor molecule in the substrate-binding site of the enzyme.

Novel zierane- and guaiane-type sesquiterpenes from the root of Melicope denhamii.

Two novel zierane-type sesquiterpenes, named melicodenones A and B (1 and 2, resp.), and three new guaiane-type sesquiterpenes, named melicodenones C-E (3-5), were isolated from the root of Melicope denhamii (Seem.) T. G. Hartley together with zierone (6). Their structures were established by extensive NMR-spectroscopic analyses. Compounds 1-6 were tested for cytotoxicity using human colon cancer DLD-1 cells, and melicodenone A (1) was found to exhibit moderate activity.

Sesquiterpenes from the aerial part of Chloranthus japonicus and their cytotoxicities.

Four new sesquiterpenes, chlorajapolides F-I (1-4), along with nine known terpenoids (5-13) were isolated from the aerial part of Chloranthus japonicus. Their structures were elucidated on the basis of spectroscopic analysis, and a lindenane sesquiterpene, named 9-hydroxy-heterogorgiolide, previously isolated from the C. japonicus, was revised as its 8-epimer (1a). Moreover, methanol extract (ME), EtOAc fraction (EF), water fraction (WF), and all isolates (1a, 1-13) were evaluated for their cytotoxicities using two human cancer cell lines.