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1.
Mar Drugs ; 20(8)2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-36005485

RESUMEN

Overexpressed EGFR and mutant K-Ras play vital roles in therapeutic resistance in colorectal cancer patients. To search for an effective therapeutic protocol is an urgent task. A secondary metabolite in the sponge Hippospongia sp., Heteronemin, has been shown to induce anti-proliferation in several types of cancers. A thyroxine-deaminated analogue, tetrac, binds to integrin αvß3 to induce anti-proliferation in different cancers. Heteronemin- and in combination with tetrac-induced antiproliferative effects were evaluated. Tetrac enhanced heteronemin-induced anti-proliferation in HT-29 cells (KRAS WT CRC) and HCT-116 cells (KRAS MT CRC). Heteronemin and tetrac arrested cell cycle in different phases. Combined treatment increased the cell accumulation in sub-G1 and S phases. The combined treatment also induced the inactivation of EGFR signaling and downregulated the phosphorylated ERK1/2 protein in both cell lines. Heteronemin and the combination showed the downregulation of the phosphorylated and total PI3K protein in HT-29 cells (KRAS WT CRC). Results by NanoString technology and RT-qPCR revealed that heteronemin and combined treatment suppressed the expression of EGFR and downstream genes in HCT-116 cells (KRAS MT CRC). Heteronemin or combined treatment downregulated genes associated with cancer progression and decreased cell motility. Heteronemin or the combined treatment suppressed PD-L1 expression in both cancer cell lines. However, only tetrac and the combined treatment inhibited PD-L1 protein accumulation in HT-29 cells (KRAS WT CRC) and HCT-116 cells (KRAS MT CRC), respectively. In summary, heteronemin induced anti-proliferation in colorectal cancer cells by blocking the EGFR-dependent signal transduction pathway. The combined treatment further enhanced the anti-proliferative effect via PD-L1 suppression. It can be an alternative strategy to suppress mutant KRAS resistance for anti-EGFR therapy.


Asunto(s)
Neoplasias Colorrectales , Tiroxina , Antígeno B7-H1/metabolismo , Línea Celular Tumoral , Proliferación Celular , Neoplasias Colorrectales/metabolismo , Receptores ErbB/metabolismo , Humanos , Mutación , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/farmacología , Transducción de Señal , Terpenos , Tiroxina/análogos & derivados
2.
J Cell Mol Med ; 22(2): 999-1013, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29214724

RESUMEN

CME-1, a novel water-soluble polysaccharide purified from Ophiocordyceps sinensis mycelia, has anti-oxidative, antithrombotic and antitumour properties. In this study, other major attributes of CME-1, namely anti-inflammatory and immunomodulatory properties, were investigated. Treating lipopolysaccharide (LPS)-stimulated RAW 264.7 cells with CME-1 concentration-dependently suppressed nitric oxide formation and inducible nitric oxide synthase (iNOS) expression. In the CME-1-treated RAW 264.7 cells, LPS-induced IκBα degradation and the phosphorylation of p65, Akt and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38, were reduced. Treatment with a protein phosphatase 2A (PP2A)-specific inhibitor, significantly reversed the CME-1-suppressed iNOS expression; IκBα degradation; and p65, Akt and MAPK phosphorylation. PP2A activity up-regulation and PP2A demethylation reduction were also observed in the cells. Moreover, CME-1-induced PP2A activation and its subsequent suppression of LPS-activated RAW 264.7 cells were diminished by the inhibition of ceramide signals. LPS-induced reactive oxygen species (ROS) and hydroxyl radical formation were eliminated by treating RAW 264.7 cells with CME-1. Furthermore, the role of ceramide signalling pathway and anti-oxidative property were also demonstrated in CME-1-mediated inhibition of LPS-activated primary peritoneal macrophages. In conclusion, CME-1 suppressed iNOS expression by up-regulating ceramide-induced PP2A activation and reducing ROS production in LPS-stimulated macrophages. CME-1 is a potential therapeutic agent for treating inflammatory diseases.


Asunto(s)
Ceramidas/farmacología , Lipopolisacáridos/farmacología , Macrófagos/enzimología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Polisacáridos/farmacología , Proteína Fosfatasa 2/metabolismo , Animales , Antioxidantes/farmacología , Cordyceps/química , Activación Enzimática/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Inhibidor NF-kappaB alfa/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico/biosíntesis , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos
3.
Haematologica ; 98(5): 793-801, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23065519

RESUMEN

Thrombin activates platelets mainly through protease-activated receptor (PAR)1 and PAR4. However, downstream platelet signaling between PAR1 and PAR4 is not yet well understood. This study investigated the relationship between nSMase/ceramide and the NF-κB signaling pathway in PARs-mediated human platelet activation. The LC-MS/MS, aggregometry, flow cytometry, immunoprecipitation, and mesenteric microvessels of mice were used in this study. Human platelets stimulated by thrombin, 3-OMS (a neutral sphingomyelinase [nSMase] inhibitor) and Bay11-7082 (an NF-κB inhibitor) significantly inhibited platelet activation such as P-selectin expression. Thrombin also activated IκB kinase (IKK)ß and IκBα phosphorylation; such phosphorylation was inhibited by 3-OMS and SB203580 (a p38 MAPK inhibitor). Moreover, 3-OMS abolished platelet aggregation, IKKß, and p38 MAPK phosphorylation stimulated by PAR4-AP (a PAR4 agonist) but not by PAR1-AP (a PAR1 agonist). Immunoprecipitation revealed that nSMase was directly associated with PAR4 but not PAR1 in resting platelets. In human platelets, C24:0-ceramide is the predominant form of ceramides in the LC/MS-MS assay; C24:0-ceramide increases after stimulation by thrombin or PAR4-AP, but not after stimulation by PAR1-AP. We also found that C2-ceramide (a cell-permeable ceramide analog) activated p38 MAPK and IKKß phosphorylation in platelets and markedly shortened the occlusion time of platelet plug formation in vivo. This study demonstrated that thrombin activated nSMase by binding to PAR4, but not to PAR1, to increase the C24:0-ceramide level, followed by the activation of p38 MAPK-NF-κB signaling. Our results showed a novel physiological significance of PAR4-nSMase/ceramide-p38 MAPK-NF-κB cascade in platelet activation.


Asunto(s)
Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Ceramidas/metabolismo , FN-kappa B/metabolismo , Receptores de Trombina/metabolismo , Esfingomielina Fosfodiesterasa/metabolismo , Trombina/farmacología , Humanos , Activación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria , Unión Proteica , Transducción de Señal/efectos de los fármacos , Esfingosina/análogos & derivados , Esfingosina/farmacología , Espectrometría de Masas en Tándem , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
4.
Biomater Sci ; 11(13): 4522-4536, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37158091

RESUMEN

Aging involves tissue and cell potential dysfunction characterized by stem cell senescence and extracellular matrix microenvironment (ECM) alteration. Chondroitin sulfate (CS), found in the ECM of normal cells and tissues, aids in maintaining tissue homeostasis. Here, CS-derived biomaterial (CSDB) from sturgeon is extracted to investigate its antiaging effect in senescence-accelerated mouse prone-8 (SAMP8) mice and elucidate the underlying mechanism of its action. Although CSDB has been widely extracted from different sources and used as a scaffold, hydrogel, or drug carrier for the treatment of various pathological diseases, CSDB has not yet been used as a biomaterial for the amelioration of senescence and aging features. In this study, the extracted sturgeon CSDB showed a low molecular weight and comprised 59% 4-sulfated CS and 23% 6-sulfated CS. In an in vitro study, sturgeon CSDB promoted cell proliferation and reduced oxidative stress to inhibit stem cell senescence. In an ex vivo study, after oral CSDB treatment of SAMP8 mice, the stem cells were extracted to analyze the p16Ink4a and p19Arf gene-related pathways, which were inhibited and then SIRT-1 gene expression was upregulated to reprogram stem cells from a senescence state for retarding aging. In an in vivo study, CSDB also restored the aging-phenotype-related bone mineral density and skin morphology to prolong longevity. Thus, sturgeon CSDB may be useful for prolonging healthy longevity as an anti-aging drug.


Asunto(s)
Antioxidantes , Longevidad , Ratones , Animales , Sulfatos de Condroitina/farmacología , Envejecimiento/genética , Senescencia Celular , Peces/genética , Células Madre , Expresión Génica
5.
FASEB J ; 25(10): 3661-73, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21705667

RESUMEN

Inactivation of glycogen synthase kinase (GSK)-3 has been implicated in cancer progression. Previously, we showed an abundance of inactive GSK-3 in the human chronic myeloid leukemia (CML) cell line. CML is a hematopoietic malignancy caused by an oncogenic Bcr-Abl tyrosine kinase. In Bcr-Abl signaling, the role of GSK-3 is not well defined. Here, we report that enforced expression of constitutively active GSK-3 reduced proliferation and increased Bcr-Abl inhibition-induced apoptosis by nearly 1-fold. Bcr-Abl inhibition activated GSK-3 and GSK-3-dependent apoptosis. Inactivation of GSK-3 by Bcr-Abl activity is, therefore, confirmed. To reactivate GSK-3, we used glucosylceramide synthase (GCS) inhibitor PDMP to accumulate endogenous ceramide, a tumor-suppressor sphingolipid and a potent GSK-3 activator. We found that either PDMP or silence of GCS increased Bcr-Abl inhibition-induced GSK-3 activation and apoptosis. Furthermore, PDMP sensitized the most clinical problematic drug-resistant CML T315I mutant to Bcr-Abl inhibitor GNF-2-, imatinib-, or nilotinib-induced apoptosis by >5-fold. Combining PDMP and GNF-2 eliminated transplanted-CML-T315I-mutants in vivo and dose dependently sensitized primary cells from CML T315I patients to GNF-2-induced proliferation inhibition and apoptosis. The synergistic efficacy was Bcr-Abl restricted and correlated to increased intracellular ceramide levels and acted through GSK-3-mediated apoptosis. This study suggests a feasible novel anti-CML strategy by accumulating endogenous ceramide to reactivate GSK-3 and abrogate drug resistance.


Asunto(s)
Apoptosis/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Genes abl , Glucosiltransferasas/antagonistas & inhibidores , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Morfolinas/farmacología , 1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/farmacología , Animales , Apoptosis/fisiología , Línea Celular Tumoral , Ceramidas/metabolismo , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos , Femenino , Genes abl/efectos de los fármacos , Genes abl/fisiología , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Inmunoglobulina G , Melfalán , Ratones , Ratones SCID , Mutación , Neoplasias Experimentales , Pirimidinas , Trasplante Heterólogo
6.
J Biomed Biotechnol ; 2012: 673764, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22187536

RESUMEN

The major cell wall constituent of Ganoderma lucidum (G. lucidum) is ß-1,3-glucan. This study examined the polysaccharide from the residues of alkaline-extracted fruiting bodies using high-performance anion-exchange chromatography (HPAEC), and it employed nuclear magnetic resonance (NMR) and mass spectrometry (MS) to confirm the structures. We have successfully isolated low-molecular-weight ß-1,3-glucan (LMG), in high yields, from the waste residue of extracted fruiting bodies of G. lucidum. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay evaluated the capability of LMG to suppress H2O2-induced cell death in RAW264.7 cells, identifying that LMG protected cells from H2O2-induced damage. LMG treatment decreased H2O2-induced intracellular reactive oxygen species (ROS) production. LMG also influenced sphingomyelinase (SMase) activity, stimulated by cell death to induce ceramide formation, and then increase cell ROS production. Estimation of the activities of neutral and acid SMases in vitro showed that LMG suppressed the activities of both neutral and acid SMases in a concentration-dependent manner. These results suggest that LMG, a water-soluble ß-1,3-glucan recycled from extracted residue of G. lucidum, possesses antioxidant capability against H2O2-induced cell death by attenuating intracellular ROS and inhibiting SMase activity.


Asunto(s)
Antioxidantes/química , Antioxidantes/farmacología , Frutas/química , Reishi/química , beta-Glucanos/química , beta-Glucanos/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Peróxido de Hidrógeno/antagonistas & inhibidores , Peróxido de Hidrógeno/toxicidad , Ratones , Peso Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/metabolismo , Esfingomielina Fosfodiesterasa/metabolismo
7.
Molecules ; 17(6): 7387-400, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-22706370

RESUMEN

Neutral and acidic monosaccharide components in Ganoderma lucidum polysaccharide are readily labeled with 2,3-naphthalenediamine, and the resulting saccharide-naphthimidazole (NAIM) derivatives are quantified by capillary electrophoresis (CE) in borate buffer. Using sulfated-α-cyclodextrin as the chiral selector, enantiomers of monosaccharide-NAIMs are resolved on CE in phosphate buffer, allowing a simultaneous determination of the absolute configuration and sugar composition in the mucilage polysaccharide of a medicinal herb Dendrobium huoshanense. Together with the specific enzymatic reactions of various glycoside hydrolases on the NAIM derivatives of glycans, the structures of natural glycans can be deduced from the digestion products identified by CE analysis. Though heparin dissachrides could be successfully derived with the NAIM-labeling method, the heparin derivatives with the same degree of sulfation could not be separated by CE.


Asunto(s)
2-Naftilamina/análogos & derivados , Carbohidratos/química , 2-Naftilamina/química , Dendrobium/química , Electroforesis Capilar , Heparina/química , Polisacáridos/química , Reishi/química , Coloración y Etiquetado
8.
Molecules ; 17(5): 4950-61, 2012 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-22547317

RESUMEN

MALDI-TOF MS provides rapid and sensitive analyses of larger biomolecules. However, MS analyses of polysaccharide have been reported to have lower sensitivity compared to peptides and proteins. Here, we investigated some polysaccharides chemically derivatized by permethylation and ortho-phenylene diamine (OPD) tagging. Methylated glycan is obviously able to improve the sensitivity for mass spectrometry detection. Oxidative condensation by UV-activation tagging to saccharides by OPD and peptide-OPD also improve the sensitivity of MALDI-TOF MS analyses. Polysaccharides including dextran, glucomannan, arabinoxylan, arabinogalactan and beta-1,3-glucan, isolated from nutritional supplements of Ganoderma lucidum and Saccharomyces pastorianus were measured using MALDI-TOF MS with 2,5-dihydroxybenzoic acid (2,5-DHB) as the matrix. These glycans were also derivatized to methylated and benzimidazole-tagged glycans by chemical transformation for molecular weight analysis. The derivatized polysaccharides showed excellent MALDI-TOF MS signal enhancement in the molecular weight range from 1 to 5 kDa. Here, we demonstrate an efficient method to give glycan-benzimidazole (glycan-BIM) derivatives for polysaccharide determination in MALDI-TOF MS. Therefore, permethylated or benzimidazole-derivatized polysaccharides provide a new option for polysaccharide analysis using MALDI-TOF MS.


Asunto(s)
Bencimidazoles/química , Fenilendiaminas/química , Polisacáridos/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Gentisatos/química , Metilación , Peso Molecular , Oxidación-Reducción , Péptidos/química , Reishi/química , Saccharomyces/química , Sensibilidad y Especificidad , Rayos Ultravioleta
9.
Front Cell Dev Biol ; 10: 829788, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35237605

RESUMEN

Doxycycline, an antibiotic, displays the inhibition of different signal transduction pathways, such as anti-inflammation and anti-proliferation, in different types of cancers. However, the anti-cancer mechanisms of doxycycline via integrin αvß3 are incompletely understood. Integrin αvß3 is a cell-surface anchor protein. It is the target for estrogen, androgen, and thyroid hormone and plays a pivotal role in the proliferation, migration, and angiogenic process in cancer cells. In our previous study, thyroxine hormones can interact with integrin αvß3 to activate the extracellular signal-regulated kinase 1/2 (ERK1/2), and upregulate programmed death-ligand 1 (PD-L1) expression. In the current study, we investigated the inhibitory effects of doxycycline on proliferation in two breast cancer cell lines, MCF-7 and MDA-MB-231 cells. Doxycycline induces concentration-dependent anti-proliferation in both breast cancer cell lines. It regulates gene expressions involved in proliferation, pro-apoptosis, and angiogenesis. Doxycycline suppresses cell cyclin D1 (CCND1) and c-Myc which play crucial roles in proliferation. It also inhibits PD-L1 gene expression. Our findings show that modulation on integrin αvß3 binding activities changed both thyroxine- and doxycycline-induced signal transductions by an integrin αvß3 inhibitor (HSDVHK-NH2). Doxycycline activates phosphorylation of focal adhesion kinase (FAK), a downstream of integrin, but inhibits the ERK1/2 phosphorylation. Regardless, doxycycline-induced FAK phosphorylation is blocked by HSDVHK-NH2. In addition, the specific mechanism of action associated with pERK1/2 inhibition via integrin αvß3 is unknown for doxycycline treatment. On the other hand, our findings indicated that inhibiting ERK1/2 activation leads to suppression of PD-L1 expression by doxycycline treatment. Furthermore, doxycycline-induced gene expressions are disturbed by a specific integrin αvß3 inhibitor (HSDVHK-NH2) or a mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinases (ERK) kinase (MAPK/ERK, MEK) inhibitor (PD98059). The results imply that doxycycline may interact with integrin αvß3 and inhibits ERK1/2 activation, thereby regulating cell proliferation and downregulating PD-L1 gene expression in estrogen receptor (ER)-negative breast cancer MDA-MB-231 cells.

10.
J Lipid Res ; 52(3): 471-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21217100

RESUMEN

A novel water-soluble polysaccharide fraction, CME-1, with a molecular mass of 27.6 kDa and containing mannose and galactose in a respective ratio of 4:6, was prepared from Cordyceps sinensis mycelia and identified by NMR and GC-MS. In the current study, we examined whether CME-1 has anti-inflammatory effects in RAW264.7 cells. The ability of CME-1 to inhibit H(2)O(2)-induced cell death in RAW264.7 cells was assessed by using an MTT assay and annexin V/propidium iodide double staining; we found that CME-1 protected cells against H(2)O(2)-induced injury. H(2)O(2)-induced intracellular oxidative stress and mitochondrial membrane depolarization were also diminished with CME-1 treatment. We evaluated the hydroxyl radical scavenging ability of CME-1 by using the DMPO-electron spin resonance technique, which indicated that CME-1 acts as an intracellular antioxidant in a concentration-dependent manner through a mechanism other than its scavenging activity. Activities of both neutral and acid sphingomyelinases (SMases) were assessed in vitro, and results showed that the CME-1 inhibited activities of both neutral and acid SMases in a concentration-dependent manner. CME-1 reduced H(2)O(2) treatment-elevated C16- and C18-ceramide levels measured by LC/MS/MS in RAW264.7 cells. Results suggest that CME-1 protects RAW264.7 cells against oxidative stress through inhibition of SMase activity and reduction of C16- and C18-ceramide levels.


Asunto(s)
Cordyceps/química , Citoprotección/efectos de los fármacos , Macrófagos/efectos de los fármacos , Micelio/química , Estrés Oxidativo/efectos de los fármacos , Polisacáridos/farmacología , Esfingomielina Fosfodiesterasa/antagonistas & inhibidores , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Ceramidas/metabolismo , Cordyceps/crecimiento & desarrollo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/farmacología , Peróxido de Hidrógeno/farmacología , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Macrófagos/citología , Macrófagos/metabolismo , Ratones , Membranas Mitocondriales/efectos de los fármacos , Micelio/crecimiento & desarrollo , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Solubilidad , Agua/química
11.
Phytochemistry ; 187: 112776, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33933828

RESUMEN

Transformation of 15-ene steviol (ent-13-hydroxy-kaur-15-en-19-oic acid) by growth cultures of Aspergillus niger BCRC 32720, Cunninghamella bainieri ATCC 9244, and Mortierella isabellina ATCC 38063 was conducted to generate various derivatives for the development of bioactive compounds. Four previously undescribed compounds along with six known compounds were obtained. The newly identified isolates were characterized using 1D and 2D NMR, IR, and HRESIMS, and three compounds were further confirmed by X-ray crystallographic analyses. Subsequently, the effects of 15-ene steviol and its derivatives on lipopolysaccharide (LPS)-induced cytokine production by THP-1 cells were examined, with dexamethasone used as a positive control. Results indicated that most of the tested compounds showed lower inhibitory effects than those detected in the dexamethasone-treated group, except that 15-ene steviol showed better effects than dexamethasone on the reduction of LPS-induced monocyte chemoattractant protein (MCP)-1, -2, and -3 release. Three specialized products similarly showed better effects than dexamethasone on the inhibition of LPS-induced secretion of regulated on activation, normal T cell expressed and secreted (RANTES). Moreover, none of the tested compounds showed any cytotoxicity or triggered cell apoptosis, and none affected the protein integrity of toll-like receptor 4 (TLR4) or MyD88, suggesting that these compounds may exert the anti-inflammatory activity downstream of membrane-associated TLR4 and MyD88 molecules.


Asunto(s)
Cunninghamella , Aspergillus niger , Diterpenos de Tipo Kaurano , Hongos
12.
Int J Nanomedicine ; 16: 3789-3802, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34103915

RESUMEN

INTRODUCTION: It has been reported that low-molecular-weight hyaluronic acid (LMWHA) exhibits a potentially beneficial effect on cancer therapy through targeting of CD44 receptors on tumor cell surfaces. However, its applicability towards tumor detection is still unclear. In this regard, LMWHA-conjugated iron (Fe3O4) nanoparticles (LMWHA-IONPs) were prepared in order to evaluate its application for enhancing the T2* weighted MRI imaging sensitivity for tumor detection. METHODS: LMWHA and Fe3O4 NPs were produced using γ-ray irradiation and chemical co-precipitation methods, respectively. First, LMWHA-conjugated FITC was prepared to confirm the ability of LMWHA to target U87MG cells using fluorescence microscopy. The hydrodynamic size distribution and dispersion of the IONPs and prepared LMWHA-IONPs were analyzed using dynamic light scattering (DLS). In addition, cell viability assays were performed to examine the biocompatibility of LMWHA and LMWHA-IONPs toward U87MG human glioblastoma and NIH3T3 fibroblast cell lines. The ability of LMWHA-IONPs to target tumor cells was confirmed by detecting iron (Fe) ion content using the thiocyanate method. Finally, time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging and in vitro magnetic resonance imaging (MRI) were performed to confirm the contrast enhancement effect of LMWHA-IONPs. RESULTS: Florescence analysis results showed that LMWHA-FITC successfully targeted the surfaces of both tested cell types. The ability of LMWHA to target U87MG cells was higher than for NIH3T3 cells. Cell viability experiments showed that the fabricated LMWHA-IONPs possessed good biocompatibility for both cell lines. After co-culturing test cells with the LMWHA-IONPs, detected Fe ion content in the U87MG cells was much higher than that of the NIH3T3 cells in both thiocyanate assays and TOF-SIMs images. Finally, the addition of LMWHA-IONPs to the U87MG cells resulted in an obvious improvement in T2* weighted MR image contrast compared to control NIH3T3 cells. DISCUSSION: Overall, the present results suggest that LMWHA-IONPs fabricated in this study provide an effective MRI contrast agent for improving the diagnosis of early stage glioblastoma in MRI examinations.


Asunto(s)
Rayos gamma , Glioblastoma/diagnóstico por imagen , Ácido Hialurónico/química , Hierro/química , Imagen por Resonancia Magnética , Nanopartículas del Metal/química , Animales , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular/efectos de los fármacos , Glioblastoma/patología , Humanos , Ácido Hialurónico/ultraestructura , Nanopartículas del Metal/ultraestructura , Ratones , Peso Molecular , Células 3T3 NIH , Ácido Oléico/química , Tamaño de la Partícula
13.
Polymers (Basel) ; 13(11)2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34073693

RESUMEN

Osteoconduction is an important consideration for fabricating bio-active materials for bone regeneration. For years, hydroxyapatite and ß-calcium triphosphate (ß-TCP) have been used to develop bone grafts for treating bone defects. However, this material can be difficult to handle due to filling material sagging. High molecular weight hyaluronic acid (H-HA) can be used as a carrier to address this problem and improve operability. However, the effect of H-HA on bone formation is still controversial. In this study, low molecular weight hyaluronic acid (L-HA) was fabricated using gamma-ray irradiation. The viscoelastic properties and chemical structure of the fabricated hybrids were evaluated by a rheological analysis nuclear magnetic resonance (NMR) spectrum. The L-MH was mixed with H-HA to produce H-HA/L-HA hybrids at ratios of 80:20, 50:50 and 20:80 (w/w). These HA hybrids were then combined with hydroxyapatite and ß-TCP to create a novel bone graft composite. For animal study, artificial bone defects were prepared in rabbit femurs. After 12 weeks of healing, the rabbits were scarified, and the healing statuses were observed and evaluated through micro-computer tomography (CT) and tissue histological images. Our viscoelastic analysis showed that an HA hybrid consisting 20% H-HA is sufficient to maintain elasticity; however, the addition of L-HA dramatically decreases the dynamic viscosity of the HA hybrid. Micro-CT images showed that the new bone formations in the rabbit femur defect model treated with 50% and 80% L-HA were 1.47 (p < 0.05) and 2.26 (p < 0.01) times higher than samples filled with HA free bone graft. In addition, a similar tendency was observed in the results of HE staining. These results lead us to suggest that the material with an H-HA/L-HA ratio of 50:50 exhibited acceptable viscosity and significant new bone formation. Thus, it is reasonable to suggest that it may be a potential candidate to serve as a supporting system for improving the operability of granular bone grafts and enhancing new bone formations.

14.
Cells ; 9(8)2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32756527

RESUMEN

The property of drug-resistance may attenuate clinical therapy in cancer cells, such as chemoresistance to gefitinib in colon cancer cells. In previous studies, overexpression of PD-L1 causes proliferation and metastasis in cancer cells; therefore, the PD-L1 pathway allows tumor cells to exert an adaptive resistance mechanism in vivo. Nano-diamino-tetrac (NDAT) has been shown to enhance the anti-proliferative effect induced by first-line chemotherapy in various types of cancer, including colorectal cancer (CRC). In this work, we attempted to explore whether NDAT could enhance the anti-proliferative effect of gefitinib in CRC and clarified the mechanism of their interaction. The MTT assay was utilized to detect a reduction in cell proliferation in four primary culture tumor cells treated with gefitinib or NDAT. The gene expression of PD-L1 and other tumor growth-related molecules were quantified by quantitative polymerase chain reaction (qPCR). Furthermore, the identification of PI3K and PD-L1 in treated CRC cells were detected by western blotting analysis. PD-L1 presentation in HCT116 xenograft tumors was characterized by specialized immunohistochemistry (IHC) and the hematoxylin and eosin stain (H&E stain). The correlations between the change in PD-L1 expression and tumorigenic characteristics were also analyzed. (3) The PD-L1 was highly expressed in Colo_160224 rather than in the other three primary CRC cells and HCT-116 cells. Moreover, the PD-L1 expression was decreased by gefitinib (1 µM and 10 µM) in two cells (Colo_150624 and 160426), but 10 µM gefitinib stimulated PD-L1 expression in gefitinib-resistant primary CRC Colo_160224 cells. Inactivated PI3K reduced PD-L1 expression and proliferation in CRC Colo_160224 cells. Gefitinib didn't inhibit PD-L1 expression and PI3K activation in gefitinib-resistant Colo_160224 cells. However, NDAT inhibited PI3K activation as well as PD-L1 accumulation in gefitinib-resistant Colo_160224 cells. The combined treatment of NDAT and gefitinib inhibited pPI3K and PD-L1 expression and cell proliferation. Additionally, NDAT reduced PD-L1 accumulation and tumor growth in the HCT116 (K-RAS mutant) xenograft experiment. (4) Gefitinib might suppress PD-L1 expression but did not inhibit proliferation through PI3K in gefitinib-resistant primary CRC cells. However, NDAT not only down-regulated PD-L1 expression via blocking PI3K activation but also inhibited cell proliferation in gefitinib-resistant CRCs.


Asunto(s)
Antígeno B7-H1/genética , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/patología , Resistencia a Antineoplásicos/efectos de los fármacos , Gefitinib/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Poliglactina 910/farmacología , Tiroxina/análogos & derivados , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antígeno B7-H1/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Resistencia a Antineoplásicos/genética , Gefitinib/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Células HT29 , Humanos , Ratones , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/uso terapéutico , Poliglactina 910/uso terapéutico , Tiroxina/farmacología , Tiroxina/uso terapéutico , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Planta Med ; 75(11): 1237-40, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19330765

RESUMEN

Caffeic acid is a xanthine oxidase (XO) inhibitor that binds to the molybdopterin region of its active site. Caffeic acid phenethyl ester (CAPE) has higher hydrophobicity and exhibits stronger inhibition potency toward XO. Chlorogenic acid is a quinyl ester of caffeic acid that has increased hydrophilicity and also shows stronger XO inhibitory activity compared with caffeic acid. Caffeic acid and CAPE showed competitive inhibition against XO, whereas chlorogenic acid displayed mixed-type inhibition, implying that it binds to sites other than the active site. Structure-based molecular modeling was performed to account for the different binding characteristics of the hydrophobic and hydrophilic esters of caffeic acid. Chlorogenic acid showed weak binding to the molybdopterin region of XO, while it more strongly bound the flavin adenine dinucleotide region than it did the molybdopterin region. These results provide the basis for interactions of caffeic acid analogues with XO via various binding domains.


Asunto(s)
Ácidos Cafeicos/metabolismo , Ácido Clorogénico/metabolismo , Inhibidores Enzimáticos/metabolismo , Xantina Oxidasa/metabolismo , Sitios de Unión , Ácidos Cafeicos/química , Ácido Clorogénico/química , Inhibidores Enzimáticos/química , Esterificación , Modelos Moleculares , Estructura Terciaria de Proteína , Xantina Oxidasa/antagonistas & inhibidores , Xantina Oxidasa/química
16.
Food Chem Toxicol ; 132: 110693, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31336132

RESUMEN

Thyroid hormone, L-thyroxine (T4), induces inflammatory genes expressions and promotes cancer growth. It also induces expression of the checkpoint programmed death-ligand 1 (PD-L1), which plays a vital role in cancer progression. On the other hand, resveratrol inhibits inflammatory genes expressions. Moreover, resveratrol increases nuclear inducible cyclooxygenase (COX)-2 accumulation, complexes with p53, and induces p53-dependent anti-proliferation. In this study, we investigated the effect of T4 on resveratrol-induced anti-proliferation in oral cancer. T4 increased the expression and cytoplasmic accumulation of PD-L1. Increased expressions of pro-inflammatory genes, interleukin (IL)-1ß and transforming growth factor (TGF)-ß1, were shown to stimulate PD-L1 expression. T4 stimulated pro-inflammatory and proliferative genes expressions, and oral cancer cells proliferation. In contrast, resveratrol inhibited those genes and activated anti-proliferative genes. T4 retained resveratrol-induced COX-2 in cytoplasm and prevented COX-2 nuclear accumulation when resveratrol treated cancer cells. A specific signal transducer and activator of transcription 3 (STAT3) inhibitor, S31-201, blocked T4-induced inhibition and restored resveratrol-induced nuclear COX-2 accumulation. By inhibiting the T4-activated STAT3 signal transduction axis with S31-201, resveratrol was able to sequentially reestablish COX-2/p53-dependent gene expressions and anti-proliferation. These findings provide a novel understanding of the inhibitory effects of T4 on resveratrol-induced anticancer properties via the sequential expression of PD-L1 and inflammatory genes.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Citocinas/genética , Expresión Génica/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Neoplasias de la Boca/patología , Resveratrol/farmacología , Tiroxina/farmacología , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/enzimología , Ciclooxigenasa 2/metabolismo , Humanos , Neoplasias de la Boca/metabolismo , Factor de Transcripción STAT3/metabolismo
17.
Food Chem Toxicol ; 133: 110808, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31499123

RESUMEN

The obesity-regulated gene, leptin, is essential for diet. Leptin resistance causes obesity and related diseases. Certain types of diet are able to decrease leptin resistance. However, leptin has been shown to be correlated with inflammation and stimulate proliferation of various cancers. Two synthetic leptin derivatives (mimetics), OB3 and [D-Leu-4]-OB3, show more effective than leptin in reducing obesity and diabetes in mouse models. OB3 inhibits leptin-induced proliferation in ovarian cancer cells. However, effects of these mimetics in hepatocellular carcinoma (HCC) have not been investigated. In the present study, we examined the effects of OB3 and [D-Leu-4]-OB3 on cell proliferation and gene expressions in human HCC cell cultures. In contrast to what was reported for leptin, OB3 and [D-Leu-4]-OB3 reduced cell proliferation in hepatomas. Both OB3 and [D-Leu-4]-OB3 stimulated expression of pro-apoptotic genes. Both compounds also inhibited expressions of pro-inflammatory, proliferative and metastatic genes and PD-L1 expression. In combination with leptin, OB3 inhibited leptin-induced cell proliferation and expressions of pro-inflammation-, and proliferation-related genes. Furthermore, the OB3 peptide inhibited phosphoinositide 3-kinase (PI3K) activation which is essential for leptin-induced proliferation in HCC. These results indicate that OB3 and [D-Leu-4]-OB3 may have the potential to reduce leptin-related inflammation and proliferation in HCC cells.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Leptina/farmacología , Fragmentos de Péptidos/farmacología , Transducción de Señal/efectos de los fármacos , Línea Celular Tumoral , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Fosfatidilinositol 3-Quinasa/metabolismo , Inhibidores de Proteínas Quinasas/farmacología
18.
Molecules ; 13(8): 1538-50, 2008 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-18794771

RESUMEN

A novel method that uses matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to analyze molecular weight and sequencing of glucan in Ganoderma lucidum is presented. Thus, beta-glucan, which was isolated from fruiting bodies of G. lucidum, was measured in a direct and fast way using MALDI mass spectrometry. In addition, tandem mass spectrometry of permethylated glucans of G. lucidum, dextran, curdlan and maltohexaose were also pursued and different fragment patterns were obtained. The G. lucidum glucan structure was determined and this method for linkage analysis of permethylated glucan has been proven feasible.


Asunto(s)
Glucanos/química , Reishi/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Secuencia de Carbohidratos , Cuerpos Fructíferos de los Hongos/química , Metilación , Peso Molecular
19.
Sci Rep ; 8(1): 14587, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30275489

RESUMEN

Chronic kidney disease is a worldwide problem, and Pb contamination is a potential risk factor. Since current biomarkers are not sensitive for the diagnosis of Pb-induced nephrotoxicity, novel biomarkers are needed. Metformin has both hypoglycaemic effects and reno-protection ability. However, its mechanism of action is unknown. We aimed to discover the early biomarkers for the diagnosis of low-level Pb-induced nephrotoxicity and understand the mechanism of reno-protection of metformin. Male Wistar rats were randomly divided into control, Pb, Pb + ML, Pb + MH and MH groups. Pb (250 ppm) was given daily via drinking water. Metformin (50 or 100 mg/kg/d) was orally administered. Urine was analysed by nuclear magnetic resonance (NMR)-based metabolomics coupled with multivariate statistical analysis, and potential biomarkers were subsequently quantified. The results showed that Pb-induced nephrotoxicity was closely correlated with the elevation of 5-aminolevulinic acid, D-lactate and guanidinoacetic acid in urine. After co-treatment with metformin, 5-aminolevulinic acid and D-lactate were decreased. This is the first demonstration that urinary 5-aminolevulinic acid, D-lactate and guanidinoacetic acid could be early biomarkers of low-level Pb-induced nephrotoxicity in rats. The reno-protection of metformin might be attributable to the reduction of D-lactate excretion.


Asunto(s)
Factores Biológicos/orina , Intoxicación por Plomo/complicaciones , Metaboloma , Metformina/administración & dosificación , Sustancias Protectoras/administración & dosificación , Insuficiencia Renal/inducido químicamente , Insuficiencia Renal/prevención & control , Administración Oral , Animales , Modelos Animales de Enfermedad , Contaminantes Ambientales/toxicidad , Plomo/toxicidad , Espectroscopía de Resonancia Magnética , Masculino , Ratas Wistar , Resultado del Tratamiento , Urinálisis
20.
Horm Cancer ; 9(6): 420-432, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30187356

RESUMEN

Drug resistance complicates the clinical use of gefitinib. Tetraiodothyroacetic acid (tetrac) and nano-diamino-tetrac (NDAT) have been shown in vitro and in xenografts to have antiproliferative/angiogenic properties and to potentiate antiproliferative activity of other anticancer agents. In the current study, we investigated the effects of NDAT on the anticancer activities of gefitinib in human colorectal cancer cells. ß-Galactoside α-2,6-sialyltransferase 1 (ST6Gal1) catalyzes EGFR sialylation that is associated with gefitinib resistance in colorectal cancers, and this was also investigated. Gefitinib inhibited cell proliferation of HT-29 cells (K-ras wild-type), and NDAT significantly enhanced the antiproliferative action of gefitinib. Gefitinib inhibited cell proliferation of HCT116 cells (K-ras mutant) only in high concentration, and this was further enhanced by NDAT. NDAT enhancedd gefitinib-induced antiproliferation in gefitinib-resistant colorectal cancer cells by inhibiting ST6Gal1 activity and PI3K activation. Furthermore, NDAT enhanced gefitinib-induced anticancer activity additively in colorectal cancer HCT116 cell xenograft-bearing nude mice. Results suggest that NDAT may have an application with gefitinib as combination colorectal cancer therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Neoplasias Colorrectales/patología , Gefitinib/farmacología , Poliglactina 910/farmacología , Tiroxina/análogos & derivados , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Receptores ErbB/efectos de los fármacos , Receptores ErbB/metabolismo , Células HCT116 , Células HT29 , Humanos , Ratones , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Tiroxina/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
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