Multiple origins of two Ochrosia (Apocynaceae) species endemic to the Bonin (Ogasawara) Islands.

The genus, Ochrosia, is widely distributed from the West Indian Ocean throughout tropical Asia to the Middle Southern Pacific region. Ochrosia comprises many island-endemic species, suggesting that long-distance dispersal and isolation after migration are key factors for clarifying the diversification process. However, the phylogeny and biogeography of endemic Ochrosia species have not been evaluated well due to the difficulty of adequate sampling from the entire distribution range of the genus. In this study, we focused on two Ochrosia species endemic to the Bonin (Ogasawara) Islands in the northwest Pacific. The Bonin Islands are of volcanic origins and consist of two islands groups, the Ogasawara and Volcano Islands groups, approximately 300 km apart. Ochrosia nakaiana is endemic to the Ogasawara Islands group, whereas O. hexandra is endemic to the Volcano Islands group. To elucidate the phylogenetic positions of these two endemic Ochrosia species, we conducted molecular phylogenetic studies with dating and biogeographic analyses including other Ochrosia species. The phylogenetic trees showed that the two endemic species had distinct origins; O. nakaiana was closely related to O. oppositifolia and O. iwasakiana, whereas O. hexandra was related to O. mariannensis. Based on the chloroplast DNA phylogeny, the genus, Ochrosia, divided into two major lineages 36.6 million years ago. Further, the two endemic species of the Bonin Islands were independently derived approximately 1-2 million years ago. Ochrosia nakaiana originated from the Southeast Asia, New Caledonia, or other Pacific Islands, while O. hexandra derived from O. mariannensis in Micronesia. We demonstrated different origins of the two endemic Ochrosia species on the Bonin Islands. This study provided an excellent example of the complex origins and speciation of flora in the oceanic islands.

Identification of an IKKß inhibitor for inhibition of inflammation in vivo and in vitro.

Targeting on the IKKß to discover anti-inflammatory drugs has been launched for ten years, due to its predominant role in canonical NF-κB signaling. In the current study, we identified a novel IKKß inhibitor, ellipticine (ELL), an alkaloid isolated from Ochrosia elliptica and Rauvolfia sandwicensis. We found that ELL reduced the secretion and mRNA expression of TNF-α and IL-6 and decreased the protein expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in bone marrow derived macrophages (BMDMs) stimulated with LPS. In coincided with the results, ELL suppressed PGE2 and NO production in BMDMs. Underlying mechanistic study showed that ELL inhibited IκBα phosphorylation and degradation as well as NF-κB nuclear translocation, which was attributed to suppression of IKKα/ß activation. Furthermore, kinase assay and binding assay results indicated that ELL inhibited IKKß activity via directly binding to IKKß and in turn resulted in suppression of NF-κB signaling. To identify the binding sites of ELL on IKKß, IKKßC46A plasmid was prepared and the kinase assay was performed. The results demonstrated that the inhibitory effect of ELL on IKKß activity was impaired in the mutation, implying that anti-inflammatory effect of ELL was partially attributed to binding on cysteine 46. Furthermore, ELL up-regulated LC3 II expression and reduced p62 expression, suggesting that autophagy induction contributed to the anti-inflammatory effect of ELL as well. In coincided with the in vitro results, ELL increased the survival and antagonized the hypothermia in the mice with LPS-induced septic shock. Consistently, ELL reduced TNF-α and IL-6 production in the serum of the mice treated with LPS. Collectively, our study provides evidence that ELL is an IKKß inhibitor and has potential to be developed as a lead compound for treatment inflammatory diseases in the future.

Pyridocarbazole alkaloids from Ochrosia borbonica: lipid-lowering agents inhibit the cell proliferation and adipogenesis of 3T3-L1 adipocyte via intercalating into supercoiled DNA.

Bioassay-guided fractionation of an ethanolic extract of Ochrosia borbonica led to the isolation of two known pyridocarbazole alkaloids, ellipticine (1) and 9-methoxyellipticine (2), and six known monoterpenoid indole alkaloids (3-8). Lipid-lowering assay in 3T3-L1 cell model revealed that 1 and 2 could significantly inhibit the lipid droplet formation (EC50 = 0.41 and 0.92 µmol·L-1, respectively) and lower triglyceride levels by 50%-60% at the concentration of 1 µmol·L-1, being more potent than the positive drug luteolin (EC50 = 2.63 µmol·L-1). A mechanistic study indicated that 1 and 2 could intercalate into supercoiled DNA, which consequently inhibited the mitotic clonal expansion of 3T3-L1 cells at the early differentiation phase, leading to the retardance of following adipogenesis and lipogenesis. These findings suggest that 1 and 2 may serve as promising leads for further development of anti-obesity drugs.

Two new monoterpenoid indole alkaloids from the leaves and twigs of Ochrosia borbonica.

Two new monoterpenoid indole alkaloids, ochrobonines A (1) and B (2), together with five known compounds (3-7), were isolated from the leaves and twigs of Ochrosia borbonica. Their structures were determined by spectroscopic method, and the absolute configuration of compound 3 was first established by single-crystal X-ray diffraction. Compounds 1 and 2 represent a rare class of monoterpenoid indole alkaloids that with a 2-[1-(3-ethylpiperidin-4-yl)vinyl]-3-methyl-1H-indole skeleton.

A new monoterpenoid indole alkaloid from Ochrosia elliptica.

A new monoterpenoid indole alkaloid, 10-methoxyakuammidine (1), together with four known alkaloids (2-5), were isolated from the stems and leaves of Ochrosia elliptica. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. New compound 1 was evaluated for its cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. 1 exhibited inhibitory effects with IC50 values comparable to those of cisplatin.

Ochroborbone, A New Cytotoxic Indole Alkaloid from Ochrosia borbonica.

A new monoterpenoid indole alkaloid, ochroborbone (1), along with five known alkaloids (2-6), were isolated from the stems and leaves of Ochrosia borbonica. Among them, ochroborbone (1) is a rare C17-nor monoterpenoid indole alkaloid, and the known compounds (2-6) were isolated from Ochrosia for the first time. These structures were established on the basis of extensive spectroscopic methods. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1 and 2 exhibited inhibitory effects with IC50 values comparable with those of cisplatin.

Ochroborbone, A New Cytotoxic Indole Alkaloid from Ochrosia borbonica.

A new monoterpenoid indole alkaloid, ochroborbone (1), along with five known alkaloids (2-6), were isolated from the stems and leaves of Ochrosia borbonica. Among them, ochroborbone (1) is a rare C17-nor monoterpenoid indole alkaloid, and the known compounds (2-6) were isolated from Ochrosia for the first time-These structures were established on the basis of extensive spectroscopic methods. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1 and 2 exhibited inhibitory effects with IC50 values comparable with those of cisplatin.

Time-Resolved Detection of Light-Induced Dimerization of Monomeric Aureochrome-1 and Change in Affinity for DNA.

Aureochrome (Aureo) is a recently discovered blue light sensor protein initially from Vaucheria frigida, in which it controls blue light-dependent branch formation and/or development of a sex organ by a light-dependent change in the affinity for DNA. Although photochemical reactions of Aureo-LOV (LOV is a C-terminal light-oxygen-voltage domain) and the N-terminal truncated construct containing a bZIP (N-terminal basic leucine zipper domain) and a LOV domain have previously been reported, the reaction kinetics of the change in affinity for DNA have never been elucidated. The reactions of Aureo where the cysteines are replaced by serines (AureoCS) as well as the kinetics of the change in affinity for a target DNA are investigated in the time-domain. The dimerization rate constant is obtained as 2.8 × 10(4) M(-1) s(-1), which suggests that the photoinduced dimerization occurs in the LOV domain and the bZIP domain dimerizes using the interaction with DNA. Surprisingly, binding with the target DNA is completed very quickly, 7.7 × 10(4) M(-1) s(-1), which is faster than the protein dimerization rate. It is proposed that the nonspecific electrostatic interaction, which is observed as a weak binding with DNA, may play a role in the efficient searching for the target sequence within the DNA.

[Studies on non-alkaloid constituents from Ochrosia elliptica].

The chemical consituents from Ochrosia elliptica were separated and purified by column chromatographies on silica gel, Sephadex LH-20, ODS and RP-HPLC. The structures of the isolated compounds were identified on the basis of physicochemical properties and spectroscopic analysis, as well as comparisons with the data in the literature. 18 compounds were isolated and elucidated as (+) -pinoresinol(1), (+) -medioresinol (2), (+) -lariciresinol (3), (+) -5'-methoxy lariciresinol(4), (+) -isolariciresinol (5), syringaresinol(6), episyringaresinol (7), ciwujiatone (8), zhebeiresinol (9), 7-hydroxycoumarin (10), 7-methoxycoumarin (11), scopoletin(12), isofraxidin(13), caffeic acid ethyl ester (14), ferulic acid (15), p-hydroxybenzaldehyde (16), vanillin (17), and vanillic acid(18). All compounds were isolated from the genus Ochrosia for the first time.

Studies on non-alkaloid constituents from Ochrosia elliptica / 中国中药杂志

The chemical consituents from Ochrosia elliptica were separated and purified by column chromatographies on silica gel, Sephadex LH-20, ODS and RP-HPLC. The structures of the isolated compounds were identified on the basis of physicochemical properties and spectroscopic analysis, as well as comparisons with the data in the literature. 18 compounds were isolated and elucidated as (+) -pinoresinol(1), (+) -medioresinol (2), (+) -lariciresinol (3), (+) -5'-methoxy lariciresinol(4), (+) -isolariciresinol (5), syringaresinol(6), episyringaresinol (7), ciwujiatone (8), zhebeiresinol (9), 7-hydroxycoumarin (10), 7-methoxycoumarin (11), scopoletin(12), isofraxidin(13), caffeic acid ethyl ester (14), ferulic acid (15), p-hydroxybenzaldehyde (16), vanillin (17), and vanillic acid(18). All compounds were isolated from the genus Ochrosia for the first time.

Alkaloids from the Australian rainforest tree Ochrosia moorei.

High-throughput screening of a plant and marine invertebrate extract library to find natural products that down-regulate expression of pro-inflammatory genes associated with the glucocorticoid receptor ligand complex led to the identification of bioactive CH2Cl 2 extracts from stems and leaves of the Queensland tree Ochrosia moorei. Bioassay-guided purification of the stem extract enabled the isolation of four alkaloids including two new compounds, ochrosamines A (1) and B (2), and the known compounds ellipticine (3) and 9-methoxyellipticine (4). The leaf extract also afforded 3 and 4 as well as apparicine (5) and desoxycordifoline (6). The structures of the two new compounds were assigned from interpretation of 2D NMR and high-resolution ESIMS data. Ellipticine and 9-methoxyellipticine were the most active components, and both displayed IC 50 values of 90 microM. Apparicine and desoxycordifoline were only very weakly active, and ochrosamines A and B were inactive.

New indole alkaloids from the roots of Ochrosia acuminata.

Two new indole alkaloids, polyneuridine-N-oxide (1) and 17-hydroxy-10-methoxy-yohimbane (2), together with seven known alkaloids were isolated from the roots of Ochrosia acuminata collected in Savu, Indonesia. 9-Methoxyellipticine (3) and ellipticine (4) were responsible for the antitumor activities of the extract. The structures of all compounds were elucidated using MS and NMR methods.