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1.
Glycoconj J ; 37(2): 187-200, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31900723

RESUMEN

3'-sialyllactose is one of the abundant components in human milk oligosaccharides (HMOs) that protect infants from various viral infections in early stages of immune system development. 3SL is a combination of lactose and sialic acid. Most sialic acids are widely expressed in animal cells and they bind to siglec proteins. In this study, we demonstrate that 3SL specifically binds to CD33. It induces megakaryocyte differentiation and subsequent apoptosis by targeting cell surface protein siglec-3 (CD33) in human chronic myeloid leukemia K562 cells. The 3SL-bound CD33 was internalized to the cytosol via caveolae-dependent endocytosis. At the molecular level, 3SL-bound CD33 recruits the suppressor of cytokine signaling 3 (SOCS3) and SH2 domain-containing protein tyrosine phosphatase 1 (SHP1). SOCS3 is degraded with CD33 by proteasome degradation, while SHP-1 activates extracellular signal-regulated kinase (ERK) to induce megakaryocytic differentiation and subsequent apoptosis. The present study, therefore, suggests that 3SL is a potential anti-leukemia agent affecting differentiation and apoptosis.


Asunto(s)
Apoptosis , Endocitosis , Megacariocitos/metabolismo , Microdominios de Membrana/metabolismo , Oligosacáridos/metabolismo , Lectina 3 Similar a Ig de Unión al Ácido Siálico/metabolismo , Diferenciación Celular , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Células K562 , Megacariocitos/citología , Unión Proteica , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Proteolisis , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo
2.
Inflammation ; 43(1): 54-65, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31720987

RESUMEN

-20pt?>Mycobacterium tuberculosis (Mtb) is a pathogenic bacterium that causes contagious tuberculosis (TB). Recently, Mtb-secreted proteins have been considered virulence factors and candidates for drugs and vaccines. Among these proteins, 6-kDa early secreted antigenic target (ESAT-6) is known to be able to induce component of matrix metalloproteinase-9 (MMP-9) in epithelial cells, leading to recruitment of macrophages. However, detailed function of ESAT-6 during macrophage recruitment to inflammatory sites remains unknown. Thus, the objective of the present study was to elucidate such function of EAST-6 and mechanism(s) involved. In the present study, we have found that recombinant ESAT-6 purified in the form of ESAT-6 double-connected structure (2E6D) could inhibit lipopolysaccharide (LPS)-induced potential of cell migration and inflammation in murine macrophage cells. Interestingly, 2E6D suppressed LPS-induced MMP-9 expression at both protein and mRNA levels as well as its enzyme activity. Levels of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) enzymes as known upregulators of MMP-9 were significantly decreased when 2E6D has been treated. In addition, nitric oxide (NO) as a second messenger was also significantly decreased by treatment with the purified 2E6D. Furthermore, 2E6D inhibited LPS-induced phosphorylation of IκB and translocation of NF-κB. Moreover, 2E6D suppressed phosphorylation of MAPK signaling proteins. Taken together, these results suggest that ESAT-6 can suppress LPS-induced MMP-9 and inflammation by downregulating COX-2, iNOS, and NO through NF-κB and MAPK signaling.


Asunto(s)
Antiinflamatorios/farmacología , Antígenos Bacterianos/farmacología , Proteínas Bacterianas/farmacología , Inflamación/prevención & control , Lipopolisacáridos/toxicidad , Macrófagos/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Animales , Movimiento Celular/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Inflamación/inducido químicamente , Inflamación/enzimología , Macrófagos/enzimología , Metaloproteinasa 9 de la Matriz/genética , Ratones , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Fosforilación , Células RAW 264.7 , Transducción de Señal
3.
Protein Expr Purif ; 164: 105453, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31299213

RESUMEN

BACKGROUND: Mycobacteria tuberculosis (Mtb), the causative agent of tuberculosis, is a slow-growing bacterium. Expression in Escherichia coli is a widely used method for large-scale production of diagnostic antigenic recombinant proteins. Expression of Mtb antigen in E. coli offers a rapid and, inexpensive alternative to conventional protein synthesis from Mtb. The addition of stabilizing additives during cell lysis or storage of Mtb antigenic protein plays a vital role in enhancing antigen stability. In this study, we evaluated the effects of additives on the stability of Mtb antigens expressed in E. coli. METHODS: Immunodominant Mtb antigens, i.e., CFP-10, Rv3872, TB7.7, and TB9.7, were cloned, and recombinant proteins overexpressed in E. coli were gradually degraded in a time-dependent manner by incubation at 37 °C. Various stabilizing additives during storage or cell lysis before protein purification were investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analysis. RESULTS: CFP-10 and Rv3872 were mainly expressed in soluble form. The degraded form of the expressed protein after incubation at 37 °C was easily observed after 1 week. Increased stability was observed in a solution containing glycine for recombinant CFP-10 and Rv3872. TB9.7 was stable in a solution containing trehalose or mannitol. TB7.7 was stable in a solution containing sucrose, glycine, or polyethylene glycol. CONCLUSION: Recombinant Mtb antigen stabilization using chemical additives inhibited protein degradation, leading to increased antigen stability and purification efficiency.


Asunto(s)
Antígenos Bacterianos/genética , Escherichia coli/genética , Mycobacterium tuberculosis/genética , Antígenos Bacterianos/química , Clonación Molecular/métodos , Excipientes/química , Expresión Génica , Humanos , Mycobacterium tuberculosis/química , Estabilidad Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Solubilidad , Tuberculosis/microbiología
4.
Front Pharmacol ; 10: 304, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31001118

RESUMEN

Toll-like receptor 4 (TLR4) and matrix metalloproteinase-9 (MMP-9) are known to play important roles in inflammatory diseases such as arteriosclerosis and plaque instability. The purpose of this study was to perform the effect of 4-O-carboxymethylascochlorin (AS-6) on MMP-9 expression in lipopolysaccharide (LPS)-induced murine macrophages and signaling pathway involved in its anti-inflammatory effect. Effect of AS-6 on MAPK/NF-κB/TLR4 signaling pathway in LPS-activated murine macrophages was examined using ELISA, Western blotting, reverse transcription polymerase chain reaction (RT-PCR) and fluorescence immunoassay. MMP-9 enzyme activity was examined by gelatin zymography. AS-6 significantly suppressed MMP-9 and MAPK/NF-κB expression levels in LPS-stimulated murine macrophages. Expression levels of inducible nitric oxide synthase (iNOS), COX2, MMP-9, JNK, ERK, p38 phosphorylation, and NF-κB stimulated by LPS were also decreased by AS-6. Moreover, AS-6 suppressed TLR4 expression and dysregulated LPS-induced activators of transcription signaling pathway. The results of this study showed that AS-6 can inhibit LPS-stimulated inflammatory response by suppressing TLR4/MAPK/NF-κB signals, suggesting that AS-6 can be used to induce the stability of atherosclerotic plaque and prevent inflammatory diseases in an in vitro model.

5.
Sci Rep ; 9(1): 4292, 2019 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-30862964

RESUMEN

N-glycolylneuraminic acid (Neu5Gc), a generic form of sialic acid, is enzymatically synthesized by cytidine-5'-monophospho-N-acetylneuraminic acid hydroxylase (CMAH). Although expression of pig CMAH gene pcmah encoding CMAH has been reported to be regulated by pathogenic infection and developmental processes, little is known about the mechanisms underlying the regulation of pcmah gene expression. The objective of this study was to determine mechanism(s) involved in intestine specific regulation of pcmah gene by identifying several cis-acting elements and nuclear transcription factors that could directly interact with these cis-acting elements. We identified intestine specific promoter region (Pi) of pcmah gene located at upstream regions of the 5'flanking region of exon 1a and found that the promoter region is responsible for the transcriptional regulation of 5'pcmah-1. Based on reporter assays using serially constructed luciferase genes with each deleted promoter, we demonstrated that the Pi promoter activity was more active in intestinal IPI-2I cells than that in kidney PK15 cells, corresponding to both mRNA expression patterns in the two cell lines. In addition, we found that Sp1 transcription factor was necessary for basal activity of Pi promoter and that Ets-1 contributed to intestine-specific activity of Pi promoter. This study helps us understand transcriptional regulation of pcmah in the intestine of pig tissues. It also allows us to consider potential roles of Neu5Gc in interaction with environmental factors present in the intestinal tissue during pathogenic infection and developmental process.


Asunto(s)
Citidina/metabolismo , Oxigenasas de Función Mixta/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Animales , Línea Celular , Citidina/química , Ácido N-Acetilneuramínico/química , Ácidos Neuramínicos/química , Ácidos Neuramínicos/metabolismo , Regiones Promotoras Genéticas/genética , Porcinos
6.
Int Immunopharmacol ; 68: 156-163, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30639961

RESUMEN

Natural compound esculentoside B (EsB), (2S,4aR,6aR,6aS,6bR,8aR,9R,10R,11S,12aR,14bS)-11-hydroxy-9-(hydroxymethyl)-2 methoxycarbonyl-2,6a,6b,9,12a-pentamethyl-10-[(2S,3R,4S,5R)-3,4,5-trihydroxyoxan-2-yl]oxy-1,3,4,5,6,6a,7,8,8a,10,11,12,13,14b-tetradecahydropicene-4a-carboxylic acid with molecular weight of 664.833, isolated from roots of Phytolacca acinosa Roxb has been widely used as a constituent of traditional Chinese medicine (TCM). However, the anti-inflammatory capacity of EsB has not been reported yet. Therefore, the objective of this study was to investigate anti-inflammatory activities of EsB in LPS-treated macrophage RAW 264.7 cells. EsB could inhibit nitric oxide (NO) production. EsB also suppressed gene and protein expression levels of inducible isoform of NO synthase (NOS) and cyclooxygenase-2 in a dose-dependent manner. In addition, EsB decreased gene expression and protein secretion levels of pro-inflammatory cytokines such as IL-1ß, TNF-α, and IL-6. EsB remarkably suppressed nuclear translocation of nuclear factor kappa-B (NF-κB) from cytosolic space. Phosphorylation of IκB was also inhibited by EsB. Moreover, EsB specifically down-regulated phospho-c-Jun N-terminal kinase (p-JNK), but not p-p38 or phospho-extracellular signal-regulated kinase 1/2 (p-ERK1/2). Taken together, these results suggest that EsB has inhibitory effect on inflammatory response by inactivating NF-κB and p-JNK. It could be used as a new modulatory drug for effective treatment of inflammation-related diseases.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Saponinas/química , Terpenos/química , Animales , Antiinflamatorios no Esteroideos/farmacología , Supervivencia Celular/efectos de los fármacos , Citocinas/genética , Citocinas/metabolismo , Lipopolisacáridos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Óxido Nítrico/metabolismo , Células RAW 264.7 , Saponinas/farmacología , Transducción de Señal/efectos de los fármacos , Terpenos/farmacología
7.
J Cell Biochem ; 120(2): 1742-1753, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30324762

RESUMEN

In our previous studies, structurally similar compounds of ascochlorin and ascofuranone exhibited anti-inflammatory activity. Neural inflammation plays a significant role in the commence and advancement of neurodegenerative diseases. It is not known whether 4-O-carboxymethylascochlorin (AS-6) regulates the initial stage of inflammatory responses at the cellular level in BV2 microglia cells. We here investigated the anti-inflammatory effects of AS-6 treatment in microglia cells with the microglial protection in neurons. We found that the lipopolysaccharide (LPS)-stimulated production of nitric oxide, a main regulator of inflammation, is suppressed by AS-6 in BV2 microglial cells. In addition, AS-6 dose-dependently suppressed the increase in COX-2 protein and messenger RNA levels in LPS-stimulated BV2 cells. Moreover, AS-6 inhibited the expression and secretion of proinflammatory cytokines in BV2 microglial cells. At the intracellular level, AS-6 inhibited LPS-activated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in BV2 microglial cells. AS-6 negatively affected mitogen-activated protein kinases (MAPK) and Akt phosphorylation: Phosphorylated forms of ERK, JNK, p38, and Akt decreased. To check whether AS-6 protects against inflammatory inducer-mediated neurotoxicity, neuronal SH-SY5Y cells were coincubated with BV2 cells in conditioned medium. AS-6 exerted a neuroprotective effect by suppressing microglial activation by LPS or amyloid-ß peptide. AS-6 is a promising suppressor of inflammatory responses in LPS-induced BV2 cells by attenuating NF-κB and MAPKs signaling. AS-6 protected against microglial-mediated neurotoxicity in SH-SY5Y and BV2 cocultured cells from LPS-induced neuroinflammation and death via inhibiting MAPK, NF-κB, and Akt pathways.

8.
J Cell Biochem ; 120(6): 9810-9819, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30525244

RESUMEN

A water-soluble saponin, Esculentoside H (EsH), 3-O-(O-ß-d-glucopyranosyl-(1→4)-ß-d-xylopyranosyl)-28-ß-d-glucopyranosylphytolaccagenin has been isolated and purified from the root extract of perennial plant Phytolacca esculenta. EsH is known to be an anticancer compound, having a capacity for TNF-α release. However, the effects of EsH on migration and growth in tumor cells have not yet been reported. In the current study, the suppressive effects of EsH on phorbol 12-myristate 13-acetate (PMA)-induced cell migration were examined in murine colon cancer CT26 cells and human colon cancer HCT116 cells. Interestingly, the transwell assay and wound healing show that EsH suppresses the PMA-induced migration and growth potential of HCT116 and CT26 colon cancer cells, respectively. EsH dose-dependently suppressed matrix metalloproteinases-9 (MMP-9) expression that was upregulated upon PMA treatment in messenger RNA levels and protein secretion. Since the expression of MMP-9 is correlated with nuclear factor-κB (NF-κB) signaling, it has been examined whether EsH inhibits PMA-induced IκB phosphorylation that leads to the suppression of NK-κB nuclear translocation. EsH repressed the phosphorylation level of JNK, but not extracellular signal-regulated kinase and p38 signaling when the cells were treated with PMA. Overall, these results demonstrated that EsH could suppress cancer migration through blockage of the JNK1/2 and NF-κB signaling-mediated MMP-9 expression.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/biosíntesis , FN-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Ácido Oleanólico/análogos & derivados , Saponinas/farmacología , Animales , Neoplasias del Colon , Células HCT116 , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ácido Oleanólico/farmacología
9.
Nanoscale ; 10(11): 5105-5113, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29446415

RESUMEN

Highly stretchable strain sensors that are capable of collecting complex multi-axial, multidimensional strain information in real time are crucial in practical applications for human motion detection. Here we present a highly sensitive and selective multidimensional resistive strain sensor based on a monolithic integration of a stiffness-variant stretchable substrate and sensing film comprising a cross-shaped silver nanowire percolation network in a single device. The multidimensional strain sensor efficiently distinguishes strains in various directions with a large gauge factor (GF) of >20 and a wide strain-detectable range of up to 60%. The sensor also features a maximum difference in GF between the x- and y-axes of >20 and long-term performance stability for up to 500 strain cycles. The practicality of the sensor as a human motion detector is demonstrated by attaching it directly to a part of the human body and measuring the multidimensional strains that occur during motions in real time.

10.
J Cell Biochem ; 119(1): 1173-1182, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28708322

RESUMEN

Gangliosides are known to specifically inhibit vascular leukocyte recruitment and consequent interaction with the injured endothelium, the basic inflammatory process. In this study, we have found that the production of nitric oxide (NO), a main regulator of inflammation, is suppressed by GM3 on murine macrophage RAW 264.7 cells, when induced by LPS. In addition, GM3 attenuated the increase in cyclooxyenase-2 (COX-2) protein and mRNA levels in lipopolysaccharide (LPS)-activated RAW 264.7 cells in a dose-dependent manner. Moreover, GM3 inhibited the expression and release of pro-inflammatory cytokines of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) in RAW 264.7 macrophages. At the intracellular level, GM3 inhibited LPS-induced nuclear translocation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and activator protein (AP)-1 in RAW 264.7 macrophages. We, therefore, investigated whether GM3 affects mitogen-activated protein kinase (MAPK) phosphorylation, a process known as the upstream signaling regulator. GM3 dramatically reduced the expression levels of the phosphorylated forms of ERK, JNK, and p38 in LPS-activated RAW 264.7 cells. These results indicate that GM3 is a promising suppressor of the vascular inflammatory responses and ganglioside GM3 suppresses the LPS-induced inflammatory response in RAW 264.7 macrophages by suppression of NF-κB, AP-1, and MAPKs signaling. Accordingly, GM3 is suggested as a beneficial agent for the treatment of diseases that are associated with inflammation.


Asunto(s)
Antiinflamatorios/farmacología , Gangliósido G(M3)/farmacología , Lipopolisacáridos/efectos adversos , Macrófagos/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Citocinas , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica , Macrófagos/química , Ratones , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Fosforilación/efectos de los fármacos , Células RAW 264.7 , Factor de Transcripción AP-1/metabolismo
11.
Oncotarget ; 8(42): 72205-72219, 2017 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-29069780

RESUMEN

The disialic acid-containing glycosphingolipid GD3 recruited membrane transglutaminase 2 (TG2) as a signaling molecule for erythroid differentiation in human chronic myelogenous leukemia (CML) K562 cells. The α1-adrenergic receptor (α1-AR)/TG2-mediated signaling pathway regulated GD3 functions, including gene expression and production, to differentiate CML K562 cells into erythroid lineage cells. Epinephrine, an AR agonist, increased membrane recruitment as well as GTP-photoaffinity of TG2, inducing GD3 synthase gene expression. Epinephrine activated PI3K/Akt signaling and GTPase downstream of TG2 activated Akt. The coupling of TG2 and GD3 production was specifically suppressed by prazosin (α1-AR antagonist), but not by propranolol (ß-AR antagonist) or rauwolscine (α2-AR antagonist), indicating α1-AR specificity. Small interfering RNA (siRNA) experiment results indicated that the α1-AR/TG2-mediated signaling pathway activated PKCs α and δ to induce GD3 synthase gene expression. Transcription factors CREB, AP-1, and NF-κB regulated GD3 synthase gene expression during α1-AR-induced differentiation in CML K562 cells. In addition, GD3 synthase gene expression was upregulated in TG2-transfected cells via α1-AR with expression of erythroid lineage markers and benzidine-positive staining. α1-AR/TG2 signaling pathway-directed GD3 production is a crucial step in erythroid differentiation of K562 cells and GD3 interacts with α1-AR/TG2, inducing GD3/α1-AR/TG2-mediated erythroid differentiation. These results suggest that GD3, which acts as a membrane mediator of erythroid differentiation in CML cells, provides a therapeutic avenue for leukemia treatment.

12.
Oncotarget ; 8(35): 58152-58162, 2017 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-28938544

RESUMEN

The oligosaccharides in human milk have various biological functions. However, the molecular mechanism(s) underlying the anti-angiogenic action of sialylated human milk oligosaccharides (HMOs) are still unclear. Here, we show that siallylactose (SL) found in human milk can inhibit the activation of vascular endothelial growth factor (VEGF)-mediated VEGF receptor-2 (VEGFR-2) by binding to its VEGF binding site (second and third IgG-like domains), thus blocking downstream signal activation. SL also inhibits growth of VEGF-stimulated endothelial cells. In endothelial cells treated with VEGF, SL diminished tube formation, migration, and the arrangement of actin filament. In addition, SL clearly suppressed VEGF-induced neovascularization in an in vivo Matrigel plug assay. Notably, SL prevented the growth of tumor cells, and angiogenesis on tumor tissues in in vivo mice models allotransplanted with Lewis lung carcinoma, melanoma, and colon carcinoma cells. Taken together, we have demonstrated that the sialylated milk oligosaccharide sialyllactose functions as an inhibitor of angiogenesis through suppression of VEGF-mediated VEGFR-2 activation in endothelial cells, Accordingly, it could be a novel candidate for the development of anti-angiogenic drugs without any side effects.

14.
Int J Biol Sci ; 13(3): 265-275, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28367091

RESUMEN

The disialoganglioside GD3 has been considered to be involved in tumor progression or suppression in various tumor cells. However, the significance of the biological functions of GD3 in breast cancer cells is still controversial. This prompted us to study the possible relationship(s) between GD3 expression and the metastatic potential of a breast cancer MDA-MB231 cells as an estrogen receptor negative (ER-) type. The human GD3 synthase cDNA was transfected into MDA-MB231 cells, and G-418 bulk selection was used to select cells stably overexpressing the GD3 synthase. In vitro invasion potentials of the GD3 synthase over-expressing cells (pc3-GD3s) were significantly suppressed when compared with control cells. Expression of intercellular adhesion molecule-1 (ICAM-1; CD54) was down-regulated in the pc3-GD3s cells and the decrease in ICAM-I expression is directly related to the decrease in invasiveness of the pc3-GD3s cells. Another type of ER negative SK-BR3 cells exhibited the similar level of ICAM-1 expression as MDA-MB231 cells, while the ER positive MCF-7 cells (ER+) showed the increased expression level of ICAM-1. Then, we investigated signaling pathways known to control ICAM-1 expression. No difference was observed in the phosphorylation of ERK and p38 between the pc3-GD3s and control cells (pc3), but the activation of AKT was inhibited in pc3-GD3s, and not in the control (pc3). In addition, the composition of total gangliosides was changed between control (pc3) and pc3-GD3s cells, as confirmed by HPTLC. The pc3-GD3s cells had an accumulation of the GD2 instead of the GD3. RT-PCR results showed that not only GD3 synthase, but also GM2/GD2 synthase (ß4-GalNc T) expression was increased in pc3-GD3s cells. Overexpression of GD3 synthase suppresses the invasive potential of human breast cancer MDA-MB-231 cells through down-regulation of ICAM-1 and the crucial pathway to allow the apoptotic effect has been attributed to accumulation of the GD2 ganglioside. ER has been linked to the ICAM-1 expression with GD3 to GD2 conversion in human breast cancer cells. This is the first finding of the endogenous sialyltransferase functions in tumor cells.


Asunto(s)
Gangliósidos/farmacología , Molécula 1 de Adhesión Intercelular/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Células MCF-7 , Fosforilación/efectos de los fármacos , Fosforilación/genética , Sialiltransferasas/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
15.
PLoS One ; 12(2): e0171322, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28207754

RESUMEN

The natural fungal compound ascofuranone (5-chloro-3-[(2E,6E)-7-[(2S)-5,5-dimethyl-4-oxo-tetrahydrofuran-2-yl]-3-methyl-octa-2,6-dienyl]-2,4-dihydroxy-6-methyl-benzaldehyde, MW 420.93) (AF) isolated from Ascochyta viciae has been known to promote cell cycle arrest and inhibit invasion of tumor cells. We have previously studied a structurally similar compound ascochlorin (ASC; MW 404.93) with regard to its anti-inflammatory activity in LPS- stimulated RAW 264.7 macrophages. In order to examine the relationship between the anti-inflammatory activities and the molecular differences between AF and ASC, the activity of AF is herein studied, because ASC has a unique trimethyl oxocyclohexyl structure, while AF has a unique dimethyl-oxo-tetrahydrofuran structure. AF dose-dependently inhibited the production of NO and iNOS and the COX-2 mRNA and protein levels in RAW 264.7 cells. In addition, AF suppressed mRNA expression levels of inflammatory cytokines such as TNF-α, IL-6, and IL-1ß, as assessed by RT-PCR. AF (30-50 µg/ml) treatment clearly inhibited the nuclear translocation of NF-κB, AP-1 (p-c-Jun) from the cytosolic space. Phosphorylation of IκB, which functions to maintain the activity of NF-κB, was decreased by AF treatment. Moreover, AF suppressed the binding of NF-κB (p65). Inhibition of IkBa phosphorylation and degradation inhibits nuclear translocation of p65. Immunofluorescence confocal microscopy analysis also revealed that translocation of NF-κB and AP-1 (p-c-Jun) was decreased upon AF treatment. AF specifically decreased the expression level of p-ERK, but not the expression level of p-p38 or p-JNK. Given these results, we suggest that AF suppresses the inflammatory response by targeting p-ERK. This indicates that AF is a negative regulator of LPS-stimulated nuclear translocation of NF-κB and AP-1 (p-c-Jun) in RAW 264.7 macrophages, and specifically it targets p-ERK. Therefore, AF and ASC exert their effects in different ways, most probably because their structural differences allow for specific recognition and inhibition of their target MAPKs. Our results further suggest that AF could be a natural bioactive compound useful for treating inflammation-mediated pathological diseases.


Asunto(s)
Antiinflamatorios/farmacología , Mediadores de Inflamación/metabolismo , Inflamación/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Sesquiterpenos/farmacología , Animales , Células Cultivadas , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Inflamación/inducido químicamente , Inflamación/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/toxicidad , Macrófagos/citología , Macrófagos/metabolismo , Ratones , FN-kappa B/metabolismo , Fosforilación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Factor de Transcripción AP-1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
16.
PeerJ ; 5: e2895, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28133573

RESUMEN

Jellyfish species are widely distributed in the world's oceans, and their population is rapidly increasing. Jellyfish extracts have several biological functions, such as cytotoxic, anti-microbial, and antioxidant activities in cells and organisms. However, the anti-cancer effect of Jellyfish extract has not yet been examined. We used chronic myelogenous leukemia K562 cells to evaluate the mechanisms of anti-cancer activity of hexane extracts from Nomura's jellyfish in vitro. In this study, jellyfish are subjected to hexane extraction, and the extract is shown to have an anticancer effect on chronic myelogenous leukemia K562 cells. Interestingly, the present results show that jellyfish hexane extract (Jellyfish-HE) induces apoptosis in a dose- and time-dependent manner. To identify the mechanism(s) underlying Jellyfish-HE-induced apoptosis in K562 cells, we examined the effects of Jellyfish-HE on activation of caspase and mitogen-activated protein kinases (MAPKs), which are responsible for cell cycle progression. Induction of apoptosis by Jellyfish-HE occurred through the activation of caspases-3,-8 and -9 and phosphorylation of p38. Jellyfish-HE-induced apoptosis was blocked by a caspase inhibitor, Z-VAD. Moreover, during apoptosis in K562 cells, p38 MAPK was inhibited by pretreatment with SB203580, an inhibitor of p38. SB203580 blocked jellyfish-HE-induced apoptosis. Additionally, Jellyfish-HE markedly arrests the cell cycle in the G0/G1 phase. Therefore, taken together, the results imply that the anti-cancer activity of Jellyfish-HE may be mediated apoptosis by induction of caspases and activation of MAPK, especially phosphorylation of p38, and cell cycle arrest at the Go/G1 phase in K562 cells.

17.
J Ethnopharmacol ; 195: 309-317, 2017 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-27876502

RESUMEN

ETHNOPHARMACOLOGY RELEVANCE: Oldenlandia diffusa (OD) has long been known as an apoptotic inducer in breast tumors in ethnomedicine. AIM OF THE STUDY: To scientifically confirm the anti-breast cancer effects of water, methanol (MeOH) and butanol (BuOH) extracts of O. diffusa on cell apoptosis, matrix metalloproteinases (MMPs), intercellular adhesion molecule (ICAM)-1 and intracellular signaling in MCF-7 breast cancer cells. MATERIALS AND METHODS: MeOH extracts (MOD) and BuOH extracts (BOD) were prepared and examined for their ability to inhibit phorbol myristate acetate (PMA)-induced matrix metalloproteinase (MMP)-9 and intercellular adhesion molecule (ICAM)-1 expressions in MCF-7 human breast cancer cells. Additionally, transwell migration, invasion and transcriptional activity were assessed. Results of immunofluorescence confocal microscopy for translocation of NF-κB and p-ERK and p-p38 were also checked. Finally, apoptotic signals including processed caspase-8, caspase-7, poly ADP-ribose polymerase, Bax and Bcl-2 were examined. RESULTS: MOD and BOD specifically inhibited PMA-induced MMP-9 expression as well as invasive and migration potential via ICAM-1. The inhibitory activity was also based on the suppressed transcriptional activity in MCF-7 breast cancer cells. Results of immunofluorescence confocal microscopy showed that translocation of NF-κB decreased upon BOD and MOD treatments, with a decreased level of p-ERK and p-p38 phosphorylation. In addition, treatment of MCF-7 cells with MOD and BOD activated apoptosis-linked proteins including enzymatically active forms of processed caspase-8, caspase-7 and poly ADP-ribose polymerase, together with increased expression of mitochondrial apoptotic protein, Bax and decreased expression of Bcl-2. CONCLUSION: The results indicate that OD as an anti-metastatic agent suppresses the metastatic response by targeting p-ERK, p-38 and NF-κB, thus reducing the invasion capacity of MCF-7 breast cancer cells through inhibition of MMP-9 and ICAM-1 expression and plays an important role in the regulation of breast cancer cell apoptosis.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Molécula 1 de Adhesión Intercelular/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Oldenlandia/química , Extractos Vegetales/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Antineoplásicos Fitogénicos/aislamiento & purificación , Proteínas Reguladoras de la Apoptosis/metabolismo , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Butanoles/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Activación Enzimática , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Molécula 1 de Adhesión Intercelular/genética , Células MCF-7 , Metanol/química , FN-kappa B/metabolismo , Invasividad Neoplásica , Metástasis de la Neoplasia , Fosforilación , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Transducción de Señal/efectos de los fármacos , Transcripción Genética/efectos de los fármacos , Transfección , Agua/química
18.
Glycoconj J ; 33(5): 779-88, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27188588

RESUMEN

In the present study, we isolated pCMAH house-keeping promoter regions (Ph), which are responsible for transcriptional regulation and which are located upstream of the alternative transcript pcmah-2. Luciferase reporter assays using serial construction of each deleted promoter demonstrated that the Ph promoter was highly active in pig-derived kidney PK15. Ph promoter of pcmah lacked a TATA box, but contained three putative Sp1 binding sites. Mutations of these Sp1 binding sites always resulted in the reduction of luciferase activities in Ph-334. In addition, treatment with mithramycin A (25-100 nM) decreased the luciferase activities of the Ph promoters and NeuGc expression in a dose-dependent manner. Electrophoretic mobility shift assay analysis revealed that the probes containing each Sp1 binding site bound to Sp1. Taken together, the results indicate that Sp1 bind to their putative binding sites on the Ph promoter regions of pcmah and positively regulate the promoter activity in pig kidney cells. Interspecies comparison of 5'UTRs and 5'flanking regions shows high homology between pig and cattle, and Sp1 binding sites existing in genomic regions corresponding Ph region are evolutionally conserved.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Genes Esenciales/fisiología , Oxigenasas de Función Mixta/biosíntesis , Ácidos Neuramínicos/metabolismo , Elementos de Respuesta/fisiología , Animales , Línea Celular , Plicamicina/farmacología , Porcinos
19.
Int J Mol Sci ; 17(5)2016 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-27144558

RESUMEN

Gangliosides have been known to play a role in the regulation of apoptosis in cancer cells. This study has employed disialyl-ganglioside GD1b to apoptosis in human breast cancer MCF-7 cells using exogenous treatment of the cells with GD1b and endogenous expression of GD1b in MCF-7 cells. First, apoptosis in MCF-7 cells was observed after treatment of GD1b. Treatment of MCF-7 cells with GD1b reduced cell growth rates in a dose and time dependent manner during GD1b treatment, as determined by XTT assay. Among the various gangliosides, GD1b specifically induced apoptosis of the MCF-7 cells. Flow cytometry and immunofluorescence assays showed that GD1b specifically induces apoptosis in the MCF-7 cells with Annexin V binding for apoptotic actions in early stage and propidium iodide (PI) staining the nucleus of the MCF-7 cells. Treatment of MCF-7 cells with GD1b activated apoptotic molecules such as processed forms of caspase-8, -7 and PARP (Poly(ADP-ribose) polymerase), without any change in the expression of mitochondria-mediated apoptosis molecules such as Bax and Bcl-2. Second, to investigate the effect of endogenously produced GD1b on the regulation of cell function, UDP-gal: ß1,3-galactosyltransferase-2 (GD1b synthase, Gal-T2) gene has been transfected into the MCF-7 cells. Using the GD1b synthase-transfectants, apoptosis-related signal proteins linked to phenotype changes were examined. Similar to the exogenous GD1b treatment, the cell growth of the GD1b synthase gene-transfectants was significantly suppressed compared with the vector-transfectant cell lines and transfection activated the apoptotic molecules such as processed forms of caspase-8, -7 and PARP, but not the levels of expression of Bax and Bcl-2. GD1b-induced apoptosis was blocked by caspase inhibitor, Z-VAD. Therefore, taken together, it was concluded that GD1b could play an important role in the regulation of breast cancer apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Gangliósidos/toxicidad , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Caspasa 7/metabolismo , Caspasa 8/metabolismo , Inhibidores de Caspasas/farmacología , Femenino , Galactosiltransferasas/genética , Galactosiltransferasas/metabolismo , Gangliósidos/biosíntesis , Humanos , Células MCF-7 , Microscopía Fluorescente , Oligopéptidos/farmacología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína X Asociada a bcl-2/metabolismo
20.
J Cell Biochem ; 117(4): 978-87, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26399466

RESUMEN

A natural compound C23 H32 O4 Cl, ascochlorin (ASC) isolated from an incomplete fungus, Ascochyta viciae has been known to have several biological activities as an antibiotic, antifungal, anti-cancer, anti-hypolipidemic, and anti-hypertension agent. In this study, anti-inflammatory activity has been investigated in lipopolysaccharide (LPS)-induced murine macrophage RAW 264.7 cells, since ASC has not been observed on the inflammatory events. The present study has clearly shown that ASC (1-50 µM) significantly suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2 ) and decreased the gene expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose-dependent manner. Moreover, ASC inhibited the mRNA expression and the protein secretion of interleukin (IL)-1ß and IL-6 but not tumor necrosis factor (TNF)-α in LPS-stimulated RAW 264.7 macrophage cells. In addition, ASC suppressed nuclear translocation and DNA binding affinity of nuclear factor-κB (NF-κB). Furthermore, ASC down-regulated phospho-extracellular signal-regulated kinase 1/2 (p-ERK1/2) and p-p38. These results demonstrate that ASC exhibits anti-inflammatory effects in RAW 264.7 macrophage cells.


Asunto(s)
Alquenos/farmacología , Antiinflamatorios no Esteroideos/farmacología , Ciclooxigenasa 2/genética , Lipopolisacáridos/antagonistas & inhibidores , Macrófagos/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Fenoles/farmacología , Transducción de Señal/efectos de los fármacos , Alquenos/aislamiento & purificación , Animales , Antiinflamatorios no Esteroideos/aislamiento & purificación , Línea Celular , Ciclooxigenasa 2/metabolismo , Dinoprostona/antagonistas & inhibidores , Dinoprostona/biosíntesis , Regulación de la Expresión Génica , Lipopolisacáridos/farmacología , Activación de Macrófagos/efectos de los fármacos , Macrófagos/citología , Macrófagos/metabolismo , Ratones , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , FN-kappa B/antagonistas & inhibidores , FN-kappa B/genética , FN-kappa B/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Fenoles/aislamiento & purificación , Transporte de Proteínas , Saccharomycetales/química , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
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