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1.
Nine species of Lantana, Lippia, Aloysia and Phyla have been examined for iridoids. Six of the species contain iridoid glucosides including pulchelloside I, mussaenoside, lamiide, durantoside I, geniposide and theviridoside as well as the sodium salts of geniposidic acid and theveside. A quinol glucoside, cornoside, has been isolated from Phyla nodiflora. The distribution of iridoids and cornoside shows a good correlation with the classification proposed by El-Gazzar and Watson.  相似文献   

2.
Cells from mice immune against soluble antigens were tested for their in vitro cytotoxicity against chicken red blood cells (CRBC) coated with these antigens. In parallel, cells from mice immune against allogeneic P815 mastocytoma cells were tested for their in -vitro cytotoxicity against P815 cells. Before the cytotoxicity test, the immune cell populations were fractionated, using four different types of techniques, to check the impact of the removal of given subpopulations of cells on cytotoxic activity.Fractionation on anti-immunoglobulin coated columns did not affect the anti P815 cytotoxicity, but markedly decreased the cytotoxicity against antigen-coated CRBC. The same results were obtained by incubation on a plastic surface and/or an “ironplus-magnet” technique. Preincubation of the cytotoxic cell populations with homologous anti-θ or heterologous anti-T antiserum, plus complement, abolished both types of cytotoxicity. However, preincubation with anti-θ or anti-T antiserum alone, without complement, also blocked the cytotoxicity against antigen-coated CRBC, but not the anti P815 cytotoxicity. In vivo injection of heterologous anti-lymphocyte gammaglobulin completely abolished the anti P815 cytotoxicity, but not the cytotoxicity against antigen-coated CRBC.These results confirm that T cells (thymus-processed lymphocytes) can kill autonomously in the anti P815 system. They also suggest that, in the cytotoxicity against antigen-coated CRBC, as effector cells, (1) non-T cells are involved, (2) T cells might not be involved.  相似文献   

3.
As a part of ongoing studies in developing novel anticancer agents, a series of modified 2,4-diaryl-5H-indeno[1,2-b]pyridines were designed, and synthesized by introducing hydroxyl and chlorine moieties. They were evaluated for topoisomerase inhibitory activity and cytotoxicity against HCT15, T47D, and HeLa cancer cell lines. This modification allowed us to demonstrate structure–activity relationship (SAR) study with respect to the non-substituted 2,4-diaryl-5H-indeno[1,2-b]pyridines. Compounds (2, 3, 4, 5, 8, and 9) with meta or para hydroxyl group on 2 or 4-phenyl ring have enhanced topo I and II inhibitory activity and cytotoxicity. However, additional substitution of chlorine group on furyl or thienyl ring (11, 12, 14, 16–18) generally reduced topo I and II inhibitory activity but improved cytotoxicity. The observation of cytotoxic properties and SAR study according to the position of hydroxyl and chlorine group will provide valuable insight for further study of development of novel anticancer agents with related scaffolds.  相似文献   

4.
A new series of 2,4-diphenyl-6-aryl pyridines containing hydroxyl group(s) at the ortho, meta, or para position of the phenyl ring were synthesized, and evaluated for topoisomerase I and II inhibitory activity and cytotoxicity against several human cancer cell lines for the development of novel anticancer agents. Structure–activity relationship study revealed that the substitution of hydroxyl group(s) increased topoisomerase I and II inhibitory activity in the order of meta > para > ortho position. Substitution of hydroxyl group on the para position showed better cytotoxicity.  相似文献   

5.
The subcutaneous fat tissue mass gradually decreases with age, and its regulation is a strategy to develop anti-aging compounds to ameliorate the photo-aging of human skin. The adipogenesis of human adipose tissue-mesenchymal stem cells (hAT-MSCs) can be used as a model to discover novel anti-aging compounds. Cinnamomum cassia methanol extracts were identified as adipogenesis-promoting agents by natural product library screening. Cinnamates, the major chemical components of Cinnamomum cassia extracts, promoted adipogenesis in hAT-MSCs. We synthesized kojyl cinnamate ester derivatives to improve the pharmacological activity of cinnamates. Structure–activity studies of kojyl cinnamate derivatives showed that both the α,β-unsaturated carbonyl ester group and the kojic acid moiety play core roles in promoting adiponectin production during adipogenesis in hAT-MSCs. We conclude that kojyl cinnamate ester derivatives provide novel pharmacophores that can regulate adipogenesis in hAT-MSCs.  相似文献   

6.
To better understand alkylating agent-induced cytotoxicity and the base lesion DNA repair process in Saccharomyces cerevisiae, we replaced the RAD27FEN1 open reading frame (ORF) with the ORF of the bifunctional human repair enzyme DNA polymerase (Pol) β. The aim was to probe the effect of removal of the incised abasic site 5′-sugar phosphate group (i.e., 5′-deoxyribose phosphate or 5′-dRP) in protection against methyl methanesulfonate (MMS)-induced cytotoxicity. In S. cerevisiae, Rad27Fen1 was suggested to protect against MMS-induced cytotoxicity by excising multinucleotide flaps generated during repair. However, we proposed that the repair intermediate with a blocked 5′-end, i.e., 5′-dRP group, is the actual cytotoxic lesion. In providing a 5′-dRP group removal function mediated by dRP lyase activity of Pol β, the effects of the 5′-dRP group were separated from those of the multinucleotide flap itself. Human Pol β was expressed in S. cerevisiae, and this partially rescued the MMS hypersensitivity observed with rad27fen1-null cells. To explore this rescue effect, altered forms of Pol β with site-directed eliminations of either the 5′-dRP lyase or polymerase activity were expressed in rad27fen1-null cells. The 5′-dRP lyase, but not the polymerase activity, conferred the resistance to MMS. These results suggest that after MMS exposure, the 5′-dRP group in the repair intermediate is cytotoxic and that Rad27Fen1 protection against MMS in wild-type cells is due to elimination of the 5′-dRP group.  相似文献   

7.
The chemical structures of nine cucurbitane-type triterpenoids from the branches and leaves of Elaeocarpus sylvestris (Elaeocarpaceae), including undescribed 29-hydroxymogroside I E2, epimogroside I E2, epimogroside I E1, 24-oxomogroside I E1, and 11-O-acetylmogroside I E1, were determined using mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy. The absolute configuration of 29-hydroxymogroside I E2 was confirmed by performing an X-ray diffraction analysis. Cucurbitacin D and 11-O-acetylmogroside I E1 showed cytotoxicity toward human leukemia HL-60, human lung adenocarcinoma A549, human hepatoma SMMC-7721, human breast cancer MCF-7, and human colon cancer SW480 cell lines. The presence of a 11-O-acetyl group might increase the cytotoxicity of this type of triterpenoids.  相似文献   

8.
1. Nocardia salmonicolor grew on a variety of alkanes, 1-phenylalkanes and 1-cyclo-hexylalkanes as sole carbon and energy sources. 2. Growth on 1-phenyldodecane in batch culture was diauxic. Isocitrate lyase activity was induced during lag phase, reaching a maximum activity in the first growth phase, during which both the aromatic ring and the side chain were degraded. However, 4-phenylbutyrate, 4-phenylbut-3-enoate, 4-phenylbut-2-enoate, 3-phenylpropionate, cinnamate and phenylacetate accumulated in the growth medium. These compounds disappeared at the onset of diauxic lag and four hydroxylated compounds accumulated; one was 4-(o-hydroxyphenyl)but-3-enoate and another was identified as 4-(o-hydroxyphenyl)butyrate. These compounds were utilized during the second growth phase. 3. Washed 1-phenyldodecane-grown cells oxidized acetate, cinnamate, 3,4-dihydroxyphenylacetate, homogentisate, o-, m- and p-hydroxyphenylacetate, phenylacetate, and 4-phenylbutyrate rapidly without lag. 4. Extracts of such cells rapidly oxidized homogentisate,3,4-dihydroxyphenylacetate, catechol and protocatechuate. 5. The organism grew readily on 4-phenylbutyrate, phenylacetate, o-hydroxyphenylacetate, homogentisate and 3,4-dihydroxyphenylacetate as sole carbon energy sources, but growth was slow on cinnamate and 4-phenylbut-3-enoate. 6. When cinnamate and phenylacetate were sole carbon sources for growth, phenylacetate and o-hydroxyphenylacetate respectively were detected in culture supernatants. 4-Phenylbut-3-enoate and 4-phenylbutyrate both yielded a mixture of cinnamate and phenylacetate. 7. It is proposed that 1-phenyldodecane is catabolized by ω-oxidation of the terminal methyl group, side-chain β-oxidation to 4-phenylbutyrate, both β- and α-oxidation to phenylacetic acid, hydroxylation to homogentisate via o-hydroxyphenylacetate and ring cleavage to maleylacetoacetate. Catabolism via 3,4-dihydroxyphenylacetate may also occur. 8. Growth on 1-phenylnonane was also diauxic and cinnamic acid, phenylpropionic acid, benzoic acid and hydroxyphenylpentanoic acid accumulated in the medium. Respirometric data and ring-cleavage enzyme activities showed similar patterns to those obtained after growth on 1-phenyldodecane. The results suggest that the main catabolic routes for 1-phenyldodecane and 1-phenylnonane may converge at cinnamate. 9. Possible reasons for diauxie are discussed.  相似文献   

9.
Responder spleen cells primed to alloantigens in vivo could generate high degree of cytotoxicity against low- or nonimmunogenic stimulators such as thymocytes or uv light-treated spleen cells in vitro. However, a removal of adherent cells from primed responder cells remarkably reduced the cytotoxicity after stimulation with such low-immunogenic stimulators. Adding a small number of peritoneal adherent cells (PACs) also suppressed the cytotoxic activity of unseparated responders against low-immunogenic stimulators. These suppressive effects by PACs were blocked by indomethacin. By adding prostaglandin E2, cytotoxic T lymphocyte (CTL) generation of primed unseparated responders against low-immunogenic stimulators was suppressed; however, cytotoxic activity against mitomycin C-treated stimulators was not suppressed. These results suggested that prostaglandins released from PACs selectively inhibited the function of splenic adherent cells that were required for CTL generation of primed responder spleen cells against low-immunogenic stimulators in vitro.  相似文献   

10.
Porcine liver carboxylesterase (carboxylic-ester hydrolase, EC 3.1.1.1) hydrolyses trans isomers of three different methyl 3-arylacrylates approximately one order of magnitude faster than the corresponding cis isomers. This phenomenon can be used for preparative production of cis esters from their trans counterparts as exemplified by methyl cinnamate. A solution of commercial, predominantly trans methyl cinnamate was irradiated by ultraviolet light and the resultant mixture of trans and cis esters was passed through a column packed with immobilized esterase. The effluent contained mainly trans cinnamic acid and cis methyl cinnamate. The latter was then extracted with methylene chloride, and the cis ester was isolated by evaporating the solvent. By esterifying the co-produced trans acid, the process can be made continuous.  相似文献   

11.
The plant alkaloid lycobetaine has potent topoisomerase-targeting properties and shows anticancer activity. Based on these findings, several lycobetaine analogs were synthesized mainly differing in their substituents at 2, 8 and 9 position and their biological activities were evaluated. The topoisomerase-targeting properties and cytotoxicity of these structural analogs were assessed in the human gastric carcinoma cell line GXF251L. Performing a plasmid relaxation assay, an increased inhibition of topoisomerase I was found with N-methylphenanthridinium chlorides bearing a 8,9-methylenedioxy moiety or a methoxy group in 2-position. Furthermore, quaternized phenanthridinium derivatives bearing either a 2-methoxy or a 8,9-methylenedioxy moiety in conjunction with a 2-hydroxy or 2-methoxy group display potent topoisomerase II inhibition as shown by decatenation of kinetoplast DNA. In general, the N-methylphenanthridinium chlorides possess more potency in inhibiting topoisomerase I than topoisomerase II. All quaternized derivatives also exhibited potent inhibition of tumor cell growth in the low micromolar concentration range. Hence, N-methylphenanthridinium compounds were found to represent a promising class of compounds, potently inhibiting both, topoisomerases I and II, and may be further developed into clinically useful topoisomerase inhibitors.  相似文献   

12.
We examined the effect of carrageenan on in vitro antibody-dependent cell-mediated cytolysis (ADCC) and spontaneous cell-mediated cytolysis (SCMC) in cultures of human peripheral blood mononuclear cells (PBL). Carrageenan, when present in the assay, nonspecifically reduced ADCC and SCMC against both Chang and chicken erythrocyte (CRBC) target cells. This reduction in cytotoxicity could not be attributed entirely to the macrophage toxic and complement-inhibitory properties of carrageenan because neither removal of complement nor macrophage depletion prevented the dose-dependent inhibition. In contrast, pretreatment of effector PBL, with carrageenan followed by removal of Carrageenan by washing did not alter ADCC or SCMC against Chang cells, which are mediated by nonphagocytic cells, but reduced both ADCC and SCMC activity against CRBC targets, which are mediated in part by macrophages. Thus, Carrageenan, when present in in vitro cell-mediated cytotoxicity assays, causes a nonspecific impairment of cytotoxicity that is independent of its anticomplement or macrophage-toxic properties.  相似文献   

13.
Sweet basil (Ocimum basilicum L.), one of the most popular aromatic plants, shows great variation in both morphology and essential oil components. In this study, the composition of 18 Turkish basil essential oils was investigated by GC and GC–MS. Variation of essential oils in the landraces was subjected to cluster analysis, and seven different chemotypes were identified. They were (1) linalool, (2) methyl cinnamate, (3) methyl cinnamate/linalool, (4) methyl eugenol, (5) citral, (6) methyl chavicol (estragol), and (7) methyl chavicol/citral. Methyl chavicol with high citral contents (methyl chavicol/citral) can be considered as a “new chemotype” in the Turkish basils. Because methyl eugenol and methyl chavicol have structural resemblance to carcinogenic phenylpropanoids, chemotypes having high linalool, methyl cinnamate or citral contents and a mixture of these is suitable to cultivate for use in industry.  相似文献   

14.
The nematicidal activity of two cassia, Cinnamomum cassia, oils (Especial and true), four cinnamon, Cinnamomum zey-lanicum, oils (technical, #500, bark and green leaf), and their compounds (e.g., trans-cinnamaldehyde and trans-cinnamic acid) toward adult Bursaphelenchus xylophilus was examined by a direct contact bioassay. Results were compared with those of 34 related compounds. As judged by 24-hour LC50 values, two cassia oils (0.084–0.085 mg/ml) and four cinnamon oils (0.064–0.113 mg/ml) were toxic toward adult B. xylophilus. Of 45 test compounds, trans-cinnamaldehyde (0.061 mg/ml) was the most active nematicide, followed by ethyl cinnamate, α-methyl-trans-cinnamaldehyde, methyl cinnamate and allyl cinnamate (0.114–0.195 mg/ml). Potent nematicidal activity was also observed with 4-methoxycinnamonitrile, trans-4-methoxycinnamaldehyde, trans-2-methoxy-cinnamaldehyde, ethyl α-cyanocinnamate, cinnamonitrile and cinnamyl bromide (0.224–0.502 mg/ml). Structure-activity relationships indicate that structural characteristics, such as types of functional groups, saturation and carbon skeleton, appear to play a role in determining the toxicities to adult B. xylophilus. Cassia and cinnamon oils and test compounds described merit further study as potential nematicides or leads for the control of pine wilt disease caused by B. xylophilus.  相似文献   

15.
Four bacteria isolated from peat biofilters, Thiobacillus thioparus DW44, Thiobacillus sp. HA43, Xanthomonas sp. DY44 and Hyphomicrobium sp. I55, were selected to enhance the removal ratios of hydrogen sulfide (H2S), methanethiol (MT) and dimethyl sulfide (DMS) in a mixed gas system. Two bacteria, DW44 and I55, which degrade H2S, MT, DMS and dimethyl disulfide (DMDS), were mixed with DY44 or HA43 which degrade only H2S and MT. Although DMS removal was significantly inhibited by the presence of H2S and MT in a peat biofilter inoculated with the single bacterium, enhanced removability of H2S, MT and DMS was observed by mixing Hyphomicrobium sp. I55 either with Thiobacillus sp. HA43 or Xanthomonas sp. DY44. The removal rate (g-S-kg-dry peat−1·d−1) by I55 after 8 d was 0.664 in total sulfur load, 0.827 g-S·kg-dry g-S·-kg-dry peat−1·d−1, but the rates by the mixed cultures of I55 plus HA43, and I55 plus DY44 were 0.760 and 0.801, respectively. In particular, DMS removability in mixed gases by a mixed culture of I55 and DY44 was almost equivalent to that by I55 when only DMS was supplied, suggesting that removal of H2S and MT, which inhibited DMS removal, was preferentially conducted by DY44 and led to improved DMS removability by I55.  相似文献   

16.
17.
Autophagy, a lysosomal pathway to maintain cellular homeostasis, is mediated via the mammalian target of rapamycin (mTOR)-dependent pathways. Hepatic stellate cells (HSCs), previously termed fat- or vitamin A-storing cells, can transdifferentiate into myofibroblast-like cells and are the most relevant cell type for overproduction of extracellular matrix (ECM) and development of liver fibrosis during injury. However, the role of autophagy in fat metabolism of HSCs remains unclear. This study investigates the regulatory effect of natural compounds on fatty acid-induced autophagy pathways of nonchemical-induced HSC (NHSC) and thioacetamide-induced HSC. Oleic acid (OA) and palmitic acid (PA) have shown a significant effect on cell proliferation with oil red O staining and Western blot confirming that OA and PA induce fat storage ability and autophagy protein expression in NHSC. Natural compounds rutin, curcumin, antroquinonol and benzyl cinnamate treatment have shown no effect on the autophagy protein expression. Nevertheless, cells pretreated with OA and PA then treated with rutin, curcumin, antroquinonol and benzyl cinnamate could significantly induce the light chain I/II (LC3 I/II) protein expression. In mTOR-dependent pathway, the PI3K-Class I, Akt, and p-mTOR proteins were decreased with PA treatment. However, there were no significant changes in PI3K-Class III and Beclin-1 protein expressions found to imply that this autophagy is unrelated to the mTOR-independent pathway. Taken together, the present study unveils rutin and curcumin as a possible effective stimulation for fatty acid-induced autophagy via mTOR-dependent pathways in NHSC. We further suggest the benefits of these natural compounds for alleviating liver fibrosis.  相似文献   

18.
As an extended study on development of anti-Alzheimer’s disease agent, we newly synthesized various dihydrofuran-fused perhydrophenanthrenes via o-quinodimethane chemistry. This study revealed that the introduction of carbon side-chain on 8-position or removal of the acetal moiety on 3-position arose a cytotoxicity on rat cortical neurons. On the other hand, the ethereal or thio-ethereal substituent on 8-position enhanced the elongation effect on Aβ-damaged neurons. The necessity of the cyano group on 10b position was also proved in this structure–activity-relationship study.  相似文献   

19.
Observations of the coral reef fish Anthias squamipinnis (Peters) suggest that the behavioural control of female-to-male sex reversal is more complex than a simple dependence on the presence or absence of a male or on simple aspects of aggression or aggressive dominance. When the behavioural interactions of all group members of small, bisexual social groups of this fish were examined before and after male removal, two behavioural features were identified as possible factors controlling the initiation of sex change: the profile for behaviours received from, and the percentage of rushes given to other group members. Males and females each showed characteristic profiles both for behaviours given and for behaviours received. On the basis of the behaviour-given profile I identified two types of female. Both types were capable of changing sex following the removal of the male. Two to four weeks were required by sex-reversing fish for the profiles for behaviour given to change to a completely male form. After male removal, the remaining females began to treat the sex-reversing fish as though she the behavioural and coloration changes of sex reversal in a female.  相似文献   

20.
Isolation of the cinnamate of grandifloric acid from Mikania oblongifolia is reported.  相似文献   

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