RESUMO
Seven novel norcycloartane glycosides, maryloside A-G (1-7), were isolated from the leaves of Cymbidium Great Flower 'Marylaurencin', along with a known norcycloartane glycoside, cymbidoside (8). These structures were determined on the basis of mainly NMR experiments as well as chemical degradation and X-ray crystallographic analysis. The isolated compounds (1-6 and 8) were evaluated for the inhibitory activity on lipopolysaccharide (LPS) and interferon-γ (IFN-γ)-stimulated nitric oxide (NO) production in RAW 264.7 cells. Consequently, 1 and 3 exhibited moderate activity.
Assuntos
Flores/química , Glicosídeos/química , Orchidaceae/química , Folhas de Planta/química , Sobrevivência Celular , Flores/metabolismo , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Óxido Nítrico/biossíntese , Orchidaceae/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/metabolismoRESUMO
Obesity is a major public health problem. An in-depth knowledge of the molecular mechanisms of oro-sensory detection of dietary lipids may help fight it. Humans and rodents can detect fatty acids via lipido-receptors, such as CD36 and GPR120. We studied the implication of the MAPK pathways, in particular, ERK1/2, in the gustatory detection of fatty acids. Linoleic acid, a dietary fatty acid, induced via CD36 the phosphorylation of MEK1/2-ERK1/2-ETS-like transcription factor-1 cascade, which requires Fyn-Src kinase and lipid rafts in human taste bud cells (TBCs). ERK1/2 cascade was activated by Ca2+ signaling via opening of the calcium-homeostasis modulator-1 (CALHM1) channel. Furthermore, fatty acid-evoked Ca2+ signaling and ERK1/2 phosphorylation were decreased in both human TBCs after small interfering RNA knockdown of CALHM1 channel and in TBCs from Calhm1-/- mice. Targeted knockdown of ERK1/2 by small interfering RNA or PD0325901 (MEK1/2 inhibitor) in the tongue and genetic ablation of Erk1 or Calhm1 genes impaired preference for dietary fat in mice. Lingual inhibition of ERK1/2 in healthy volunteers also decreased orogustatory sensitivity for linoleic acid. Our data demonstrate that ERK1/2-MAPK cascade is regulated by the opening of CALHM1 Ca2+ channel in TBCs to modulate orogustatory detection of dietary lipids in mice and humans.-Subramaniam, S., Ozdener, M. H., Abdoul-Azize, S., Saito, K., Malik, B., Maquart, G., Hashimoto, T., Marambaud, P., Aribi, M., Tordoff, M. G., Besnard, P., Khan, N. A. ERK1/2 activation in human taste bud cells regulates fatty acid signaling and gustatory perception of fat in mice and humans.
Assuntos
Ácidos Graxos/genética , Sistema de Sinalização das MAP Quinases , Papilas Gustativas/efeitos dos fármacos , Paladar/efeitos dos fármacos , Animais , Benzamidas/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Gorduras na Dieta/metabolismo , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Ácidos Graxos/metabolismo , Preferências Alimentares/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Camundongos Knockout , MicroRNAs/genética , Obesidade/metabolismo , Paladar/fisiologia , Percepção Gustatória/efeitos dos fármacos , Percepção Gustatória/genéticaRESUMO
During the search for new antitrypanosomal drug leads, four antitrypanosomal compounds, of three depsipeptides and one nortriterpenoid, were isolated from cultures of the mutant strain IU-3 of the insect pathogenic fungus Ophiocordyceps coccidiicola NBRC 100683. Their structures were identified by the analysis of high resolution-electron ionization (HR-EI)-MS and HR-FAB-MS, and (1)H- and (13)C-NMR spectra, including extensive two dimensional (2D)-heteronuclear NMR experiments, and comparison with literature data for destruxin A (1), destruxin B (2), destruxin E chlorohydrin (3) and helvolic acid (4). Compounds 1-4 showed in vitro antitrypanosomal activity against Trypanosoma brucei brucei GUTat3.1 with IC50 values of 0.33, 0.16, 0.061 and 5.08 µg/mL, respectively.
Assuntos
Antiprotozoários/farmacologia , Ascomicetos/química , Trypanosoma brucei brucei/efeitos dos fármacos , Antiprotozoários/química , Antiprotozoários/metabolismo , Ascomicetos/metabolismo , Relação Dose-Resposta a Droga , Conformação Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-AtividadeRESUMO
Implication of the long-chain fatty acid (LCFA) receptor GPR120, also termed free fatty acid receptor 4, in the taste-guided preference for lipids is a matter of debate. To further unravel the role of GPR120 in the "taste of fat", the present study was conducted on GPR120-null mice and their wild-type littermates. Using a combination of morphological [i.e., immunohistochemical staining of circumvallate papillae (CVP)], behavioral (i.e., two-bottle preference tests, licking tests and conditioned taste aversion) and functional studies [i.e., calcium imaging in freshly isolated taste bud cells (TBCs)], we show that absence of GPR120 in the oral cavity was not associated with changes in i) gross anatomy of CVP, ii) LCFA-mediated increases in intracellular calcium levels ([Ca(2+)]i), iii) preference for oily and LCFA solutions and iv) conditioned avoidance of LCFA solutions. In contrast, the rise in [Ca(2+)]i triggered by grifolic acid, a specific GPR120 agonist, was dramatically curtailed when the GPR120 gene was lacking. Taken together, these data demonstrate that activation of lingual GPR120 and preference for fat are not connected, suggesting that GPR120 expressed in TBCs is not absolutely required for oral fat detection in mice.
Assuntos
Gorduras na Dieta/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Papilas Gustativas/metabolismo , Animais , Cálcio/metabolismo , Preferências Alimentares/efeitos dos fármacos , Preferências Alimentares/fisiologia , Imuno-Histoquímica , Masculino , Camundongos , Receptores Acoplados a Proteínas G/agonistas , Papilas Gustativas/citologia , Papilas Gustativas/efeitos dos fármacosRESUMO
BACKGROUND & AIMS: It is important to increase our understanding of gustatory detection of dietary fat and its contribution to fat preference. We studied the roles of the fat taste receptors CD36 and GPR120 and their interactions via Ca(2+) signaling in fungiform taste bud cells (TBC). METHODS: We measured Ca(2+) signaling in human TBC, transfected with small interfering RNAs against messenger RNAs encoding CD36 and GPR120 (or control small interfering RNAs). We also studied Ca(2+) signaling in TBC from CD36(-/-) mice and from wild-type lean and obese mice. Additional studies were conducted with mouse enteroendocrine cell line STC-1 that express GPR120 and stably transfected with human CD36. We measured release of serotonin and glucagon-like peptide-1 from human and mice TBC in response to CD36 and GPR120 activation. RESULTS: High concentrations of linoleic acid induced Ca(2+) signaling via CD36 and GPR120 in human and mice TBC, as well as in STC-1 cells, and low concentrations induced Ca(2+) signaling via only CD36. Incubation of human and mice fungiform TBC with lineoleic acid down-regulated CD36 and up-regulated GPR120 in membrane lipid rafts. Obese mice had decreased spontaneous preference for fat. Fungiform TBC from obese mice had reduced Ca(2+) and serotonin responses, but increased release of glucagon-like peptide-1, along with reduced levels of CD36 and increased levels of GPR120 in lipid rafts. CONCLUSIONS: CD36 and GPR120 have nonoverlapping roles in TBC signaling during orogustatory perception of dietary lipids; these are differentially regulated by obesity.
Assuntos
Antígenos CD36/metabolismo , Sinalização do Cálcio , Ácido Linoleico/metabolismo , Obesidade/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Papilas Gustativas/metabolismo , Paladar , Animais , Comportamento Animal , Antígenos CD36/deficiência , Antígenos CD36/genética , Linhagem Celular , Dieta Hiperlipídica , Modelos Animais de Doenças , Preferências Alimentares , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Microdomínios da Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Obesidade/psicologia , Interferência de RNA , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/genética , Serotonina/metabolismo , Percepção Gustatória , TransfecçãoRESUMO
One new phenolic compound, sapnol A (1), and two new aromatic sophorosides, named saposides A (2) and B (3) were isolated from sugar maple sap. In addition, seven known phenolic compounds 4-10 were isolated. These structures were determined on the basis of NMR experiments as well as chemical evidence. Furthermore, all the isolated compounds 1-10 were tested for antioxidative activity by the superoxide dismutase (SOD)-like assay.
Assuntos
Acer/química , Lignanas/química , Fenóis/química , Antioxidantes/administração & dosagem , Antioxidantes/química , Canadá , Humanos , Lignanas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fenóis/isolamento & purificaçãoRESUMO
Yellow pigments, fomitellanols A (1a) and B (2a), and drimane-type sesquiterpenoid ethers of isocitric acid, cryptoporic acids P (3) and Q (4), have been isolated from the fruiting bodies of Fomitella fraxinea (Polyporaceae). Their structures were established by a combination of extensive NMR spectroscopy and/or X-ray crystallographic analyses, and their biological activity against COX-1, COX-2, and 5-LO was investigated.
Assuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Inibidores de Lipoxigenase/farmacologia , Polyporaceae/metabolismo , Sesquiterpenos/farmacologia , Cristalografia por Raios X , Inibidores de Ciclo-Oxigenase/química , Inibidores de Lipoxigenase/química , Espectroscopia de Ressonância Magnética , Sesquiterpenos Policíclicos , Sesquiterpenos/químicaRESUMO
A new phenanthrendione, ephemeranthoquinone B (1), two phenanthrenes, marylaurencinols A (2) and B (3), and a phenanthrene glucoside, marylaurencinoside A (4), were isolated from the roots of Cymbidium Great Flower Marie Laurencin, along with six known phenanthrenes, 5-10. The structures of these compounds were established by a combination of extensive NMR spectroscopy and/or X-ray crystallographic analysis and chemical degradation. The compounds were tested for antibacterial activities against Bacillus subtilis and Klebsiella pneumoniae and for cytotoxic activity against the human promyelocytic leukemia (HL-60) cell line. Compounds 1, 3, and 6 showed antibacterial activities with minimum inhibitory concentration (MIC) values in the range of 4.88 to 65.10 µM. Notably, ephemeranthoquinone B (1) had a strong antibacterial effect on B. subtilis. Furthermore, 1 exhibited moderate cytotoxic activity (IC(50) 2.8 µM) against HL-60 cells. Compounds 4-9 also showed weak cytotoxic activity against the HL-60 cell line with IC(50) values of 19.3-52.4 µM.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Orchidaceae/química , Fenantrenos/isolamento & purificação , Fenantrenos/farmacologia , Antineoplásicos Fitogênicos/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Concentração Inibidora 50 , Japão , Conformação Molecular , Estrutura Molecular , Fenantrenos/química , Raízes de Plantas/químicaRESUMO
Monocytes give rise to macrophages, osteoclasts (OCs), and dendritic cells (DCs). Macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor-kappaB (RANK) ligand induce OC differentiation from monocytes, whereas granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) trigger monocytic differentiation into DCs. However, regulatory mechanisms for the polarization of monocytic differentiation are still unclear. The present study was undertaken to clarify the mechanism of triggering the deflection of OC and DC differentiation from monocytes. GM-CSF and IL-4 abolished monocytic differentiation into OCs while inducing DC differentiation even in the presence of M-CSF and RANK ligand. GM-CSF and IL-4 in combination potently up-regulate tumor necrosis factor-alpha (TNF-alpha) converting enzyme (TACE) and activity in monocytes, causing ectodomain shedding of M-CSF receptor, resulting in the disruption of its phosphorylation by M-CSF as well as the induction of osteoclastogenesis from monocytes by M-CSF and RANK ligand. Interestingly, TACE inhibition robustly causes the resumption of the surface expression of M-CSF receptor on monocytes, facilitating M-CSF-mediated phosphorylation of M-CSF receptor and macrophage/OC differentiation while impairing GM-CSF- and IL-4-mediated DC differentiation from monocytes. These results reveal a novel proteolytic regulation of M-CSF receptor expression in monocytes to control M-CSF signaling and monocytic differentiation into macrophage/OC-lineage cells or DCs.
Assuntos
Proteínas ADAM/metabolismo , Diferenciação Celular/fisiologia , Células Dendríticas/citologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-4/metabolismo , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Proteína ADAM17 , Western Blotting , Células Dendríticas/metabolismo , Imunofluorescência , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Monócitos/citologia , Monócitos/metabolismo , Osteoclastos/citologia , Osteoclastos/metabolismo , Ligante RANK/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para CimaRESUMO
We report the synthesis and properties of two new seminaphthorhodafluor (SNARF) derivatives, SNARF-F and SNARF-Cl. Both these derivatives exhibit typical red shifts of absorption and fluorescence, and higher cell permeability as compared to traditional SNARF, while the pH-dependent dual-emission characteristics are well retained. In particular, the lower pK(a) (7.38) of SNARF-F makes it more suitable than traditional SNARF derivatives for intracellular applications.
Assuntos
Benzopiranos/síntese química , Corantes Fluorescentes/síntese química , Concentração de Íons de Hidrogênio , Fotoquímica , Benzopiranos/química , Corantes Fluorescentes/química , Espectrometria de FluorescênciaRESUMO
Vasorelaxant effects of a series of bis(bibenzyls) from liverworts such as Marchantia polymorpha and Marchantia paleacea on rat aorta demonstrated that they relaxed phenylephrine (PE)-induced contractions, which may be mediated through the increased release of NO from endothelial cells as well as opening of K(+) channels, and inhibition of Ca(2+) influx through voltage-dependent Ca(2+) channels (VDCs) and/or receptor-operated Ca(2+) channels (ROCs). Structure-activity relationship based on their structures was discussed. The presence of two aromatic rings which can be connected through two atoms bridge spacer may play an important role for vasorelaxant effect.
Assuntos
Bibenzilas/química , Hepatófitas/química , Compostos Macrocíclicos/química , Vasodilatadores/química , Animais , Aorta/citologia , Canais de Cálcio/química , Canais de Cálcio/metabolismo , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Compostos Macrocíclicos/isolamento & purificação , Compostos Macrocíclicos/farmacologia , Masculino , Óxido Nítrico/metabolismo , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Vasodilatadores/isolamento & purificação , Vasodilatadores/farmacologiaRESUMO
Fuscoporia torulosa (Pers.) (Hymenochaetaceae) is a mushroom forming woody fruiting body on living or dead trees. Two curious pentacyclic triterpenoids, fuscotorunones A and B, each of which has a unique ε-caprolactone in ring E, were isolated from the fruiting bodies of F. torulosa. The structures of fuscotorunones A and B were elucidated using MS analyses, IR spectrum and extensive 2D-homo and heteronuclear NMR data interpretation. Furthermore, a predicted biosynthetic pathway from 2,3-oxidosqualene to fuscotorunones A and B in F. torulosa is proposed.
Assuntos
Basidiomycota , Triterpenos , Caproatos , Lactonas , Estrutura MolecularRESUMO
Four new resin glycosides, namely, ipomotaosides A-D (1-4), were isolated from the dried aerial parts of Ipomoea batatas. The structures of 1-4 were elucidated by analysis of their spectroscopic data and by chemical derivatization and were tested for their anti-inflammatory activity against cyclooxygenase (COX)-1 and -2.
Assuntos
Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Inibidores de Ciclo-Oxigenase/isolamento & purificação , Inibidores de Ciclo-Oxigenase/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Ipomoea batatas/química , Plantas Medicinais/química , Anti-Inflamatórios não Esteroides/química , Ciclo-Oxigenase 1/efeitos dos fármacos , Ciclo-Oxigenase 2/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/química , Glicosídeos/química , Japão , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Resinas Vegetais/químicaRESUMO
Sparassis crispa (SC), known as Hanabiratake in Japanese, is an edible mushroom with various medicinal properties. We isolated 3 novel phthalides, designated hanabiratakelide A (1), B (2), and C (3), from the SC fruit body. In this investigation, 3 known phthalides (4-6), ubiquinone-9, and 2 known unsaturated fatty acids were also isolated. Their structures were elucidated primarily through extensive NMR experiments. The isolated compounds 1-6 were tested for their anti-oxidant activity. The in vitro superoxide dismutase-like activity of the 3 hanabiratakelides was stronger than that of vitamin C. The compounds also exerted inhibitory effects on lipopolysaccharide-stimulated nitric oxide and prostaglandin E2 production by a murine macrophage cell line, RAW264. In addition, the growth of the colon cancer cell lines Caco-2 and colon-26 was significantly inhibited by treatment with the 3 hanabiratakelides. In vivo, the frequency of azoxymethane-induced aberrant crypt foci was reduced in SC-fed F344/N rats compared to rats fed a standard diet. In conclusion, 3 novel phthalides, hanabiratakelides, derived from SC were shown to possess anti-oxidant, anti-inflammatory, and anti-tumor activity.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Anticarcinógenos/farmacologia , Antioxidantes/farmacologia , Benzofuranos/farmacologia , Neoplasias do Colo/prevenção & controle , Polyporales/química , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anticarcinógenos/isolamento & purificação , Anticarcinógenos/uso terapêutico , Antioxidantes/isolamento & purificação , Azoximetano , Benzofuranos/química , Benzofuranos/isolamento & purificação , Benzofuranos/uso terapêutico , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Dinoprostona/biossíntese , Relação Dose-Resposta a Droga , Feminino , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Ratos , Ratos Endogâmicos F344 , Superóxido Dismutase/metabolismoRESUMO
We used functional magnetic resonance imaging (fMRI) to identify brain areas involved in auditory rhythm perception. Participants listened to three rhythm sequences that varied in temporal predictability. The most predictable sequence was an isochronous rhythm sequence of a single interval (ISO). The other two sequences had nine intervals with unequal durations. One of these had interval durations of integer ratios relative to the shortest interval (METRIC). The other had interval durations of non-integer ratios relative to the shortest interval (NON-METRIC), and was thus perceptually more complex than the other two. In addition, we presented unpredictable sequences with randomly distributed intervals (RAN). We tested two hypotheses. Firstly, that areas involved in motor timing control would also process the temporal predictability of sensory cues. Therefore, there was no active task included in the experiment that could influence the participant perception or induce motor preparation. We found that dorsal premotor cortex (PMD), SMA, preSMA, and lateral cerebellum were more active when participants listen to rhythm sequences compared to random sequences. The activity pattern in supplementary motor area (SMA) and preSMA suggested a modulation dependent on sequence predictability, strongly suggesting a role in temporal sensory prediction. Secondly, we hypothesized that the more complex the rhythm sequence, the more it would engage short-term memory processes of the prefrontal cortex. We found that the superior prefrontal cortex was more active when listening to METRIC and NON-METRIC compared to ISO. We argue that the complexity of rhythm sequences is an important factor in modulating activity in many of the rhythm areas. However, the difference in complexity of our stimuli should be regarded as continuous.
Assuntos
Córtex Motor/fisiologia , Música/psicologia , Córtex Pré-Frontal/fisiologia , Estimulação Acústica , Adulto , Percepção Auditiva/fisiologia , Interpretação Estatística de Dados , Eletromiografia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Músculo Esquelético/fisiologia , Adulto JovemRESUMO
Two bis(bibenzyls), isoplagiochins A (1) and B (2) have been isolated by the guidance of inhibitory effect of tubulin polymerization from the liverwort Plagiochila fruticosa (Plagiochilaceae). Isoplagiochins A and B inhibited the polymerization of tubulin at IC(50) 50 and 25muM, respectively. Furthermore structure-activity relationship based on their conformations was discussed. The presence of two aromatic rings which can be connected through two atoms bridge spacer of double bond may serve to maintain the backbone conformation.
Assuntos
Hepatófitas/química , Compostos Macrocíclicos/farmacologia , Mitose/efeitos dos fármacos , Ligação de Hidrogênio , Compostos Macrocíclicos/química , Espectroscopia de Ressonância Magnética , Relação Estrutura-AtividadeRESUMO
Riccardin C, a nuclear receptor LXRalpha selective agonist, is an 18-membered macrocyclic bisbibenzyl isolated from several liverworts. Synthesis of riccardin C and its seven O-methylated derivatives was accomplished. The synthetic sequence highlights an intramolecular Suzuki-Miyaura coupling in the formation of the 18-membered biaryl linkage present in riccardin C. The structure-activity relationship of these compounds suggests that all of the phenolic hydroxy groups present in riccardin C are essential for the activation of LXRalpha.
Assuntos
Química Farmacêutica/métodos , Éteres Cíclicos/síntese química , Éteres Cíclicos/farmacologia , Receptores Nucleares Órfãos/antagonistas & inibidores , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Receptores X do Fígado , Modelos Químicos , Estrutura Molecular , Fenol/química , Espectrofotometria/métodos , Relação Estrutura-AtividadeRESUMO
We have designed and evaluated UTX-12 as a novel fluorescent pH probe for tumor hypoxia imaging. UTX-12 consists of a p-nitro benzyl moiety, which is a latent hypoxia-selective leaving group activated by nitro reduction, directly linked to SNARF. Although UTX-12 itself is colorless and non-fluorescent in aqueous solution, nitro reduction triggers the release of SNARF which has well-characterized long wavelength absorption and fluorescence that is sensitive to pH. The resultant SNARF, released intracellularly by enzymatic reduction of UTX-12, allows measurement of pH by pH-dependent dual emission shifts. UTX-12 showed clear differences in fluorescence behavior between hypoxic and aerobic conditions in liver microsomes and inside V79 cells. These data are confirmation that UTX-12 is biologically reduced inside tumor cells and the released SNARF should monitor intracellular pH of tumor cells selectively with reduced background signal.
Assuntos
Benzopiranos/química , Hipóxia Celular , Diagnóstico por Imagem/métodos , Dinitrobenzenos/química , Corantes Fluorescentes , Neoplasias/metabolismo , Animais , Linhagem Celular , Desenho de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Microssomos Hepáticos , Neoplasias/patologia , OxirreduçãoRESUMO
Cross-linked human leukocyte antigen (HLA) class I molecules have been shown to mediate cell death in neoplastic lymphoid cells. However, clinical application of an anti-HLA class I antibody is limited by possible side effects due to widespread expression of HLA class I molecules in normal tissues. To reduce the unwanted Fc-mediated functions of the therapeutic antibody, we have developed a recombinant single-chain Fv diabody (2D7-DB) specific to the alpha2 domain of HLA-A. Here, we show that 2D7-DB specifically induces multiple myeloma cell death in the bone marrow environment. Both multiple myeloma cell lines and primary multiple myeloma cells expressed HLA-A at higher levels than normal myeloid cells, lymphocytes, or hematopoietic stem cells. 2D7-DB rapidly induced Rho activation and robust actin aggregation that led to caspase-independent death in multiple myeloma cells. This cell death was completely blocked by Rho GTPase inhibitors, suggesting that Rho-induced actin aggregation is crucial for mediating multiple myeloma cell death. Conversely, 2D7-DB neither triggered Rho-mediated actin aggregation nor induced cell death in normal bone marrow cells despite the expression of HLA-A. Treatment with IFNs, melphalan, or bortezomib enhanced multiple myeloma cell death induced by 2D7-DB. Furthermore, administration of 2D7-DB resulted in significant tumor regression in a xenograft model of human multiple myeloma. These results indicate that 2D7-DB acts on multiple myeloma cells differently from other bone marrow cells and thus provide the basis for a novel HLA class I-targeting therapy against multiple myeloma.
Assuntos
Antígenos HLA-A/imunologia , Imunização Passiva/métodos , Fragmentos de Imunoglobulinas/farmacologia , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/terapia , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/patologia , Morte Celular/imunologia , Linhagem Celular Tumoral , Citocinas/farmacologia , Ativação Enzimática , Antígenos HLA-A/biossíntese , Humanos , Células Jurkat , Camundongos , Camundongos SCID , Mieloma Múltiplo/enzimologia , Mieloma Múltiplo/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas rho de Ligação ao GTP/metabolismoRESUMO
16-Phyllocladanol is diterpene isolated form the heartwood of Cryptomeria japonica. We demonstrate that the effect of 16-phyllocladanol on the phenotypic and functional maturation of human monocytes-derived DC in vitro. Human monocytes were exposed to 16-phyllocladanol alone, or in combination with LPS and thereafter co-cultured with naïve T cells. The expression levels of CD83 and HLA-DR on LPS-primed DC were enhanced by 16-phyllocladanol. 16-Phyllocladanol dose-dependently augmented the T cell stimulatory capacity in an allo MLR to LPS-primed DC and the production of IL-12p70 by LPS-primed DC. The cytokine production by 16-phyllocladanol-primed DC was not inhibited by anti-TLR2 and 4 mAbs. IFN-gamma secretion from naïve T cells co-cultured with DC differentiated with LPS was also augmented by 16-phyllocladanol. These results suggest that the enhancement of Th1 cells polarization to LPS-primed DC induced by 16-phyllocladanol via the activation of IL-12p70 and independent on TLR2 or TLR4.