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1.
Small ; : e2400824, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38764257

RESUMO

Halide perovskite, renowned for its multifunctional properties, shows considerable promise for realizing self-charging power systems. In this study, a lead-free methylammonium bismuth iodide (MA3Bi2I9) perovskite is used to create a self-charging power unit (SPU). This involves constructing a hybrid piezoelectric-triboelectric nanogenerator (Hybrid-TENG) and utilizing MA3Bi2I9 for energy storage as an anode in a lithium-ion battery (LIB). Initially, MA3Bi2I9 nanorods are synthesized and composited with a polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene polymer. The dielectric and mechanical properties of composite films having perovskite loading content are investigated. The optimized Hybrid-TENG exhibits superior performance, generating a voltage of 537 V, current density of 13.2 µA cm- 2, and maximum power density of 3.04 mW cm-2, which can be attributed to the high piezoelectric coefficient of MA3Bi2I9 nanorods (≈20.6 pm V-1). A MA3Bi2I9 thin film, serving as an electrode in LIB, demonstrates a high specific capacity of 2378.9 mAh cm-3 (578.8 mAh g-1) with a capacity retention of ≈87.5% over 100 cycles, underscoring its stable performance. Furthermore, a Hybrid-TENG is employed to charge the MA3Bi2I9-based LIB, thus realizing an SPU for driving portable electronics. This study highlights the promising potential of perovskites for developing efficient nanogenerators and LIBs, paving the way for sustainable energy solutions in small-scale electronics.

2.
Acta Histochem ; 124(7): 151941, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35963117

RESUMO

As a major excitatory neurotransmitter in the cephalopod visual system, glutamate signaling is facilitated by ionotropic receptors, such as α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (AMPAR). In cephalopods with large and well-developed brains, the optic lobes (OL) mainly process visual inputs and are involved in learning and memory. Although the presence of AMPAR in squid OL has been reported, the organization of specific AMPAR-containing neurons remains unknown. This study aimed to investigate the immunocytochemical localization of the AMPA glutamate receptor subtype 2/3-immunoreactive (GluR2/3-IR) neurons in the OL of Pacific flying squid (Tordarodes pacificus). Morphologically diverse GluR2/3-IR neurons were predominantly located in the tangential zone of the medulla. Medium-to-large GluR2/3-IR neurons were also detected. The distribution patterns and cell morphologies of calcium-binding protein (CBP)-IR neurons, specifically calbindin-D28K (CB)-, calretinin (CR)-, and parvalbumin (PV)-IR neurons, were similar to those of GluR2/3-IR neurons. However, two-color immunofluorescence revealed that GluR2/3-IR neurons did not colocalize with the CBP-IR neurons. Furthermore, the specific localizations and diverse types of GluR2/3-IR neurons that do not express CB, CR, or PV in squid OL were determined. These findings further contribute to the existing data on glutamatergic visual systems and provide new insights for understanding the visual processing mechanisms in cephalopods.


Assuntos
Decapodiformes , Parvalbuminas , Animais , Calbindina 1 , Calbindina 2 , Decapodiformes/metabolismo , Glutamatos , Imuno-Histoquímica , Parvalbuminas/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico
3.
Biomedicines ; 10(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35052772

RESUMO

Somatostatin (SST) is widely expressed in the brain and plays various, vital roles involved in neuromodulation. The purpose of this study is to characterize the organization of SST neurons in the Mongolian gerbil visual cortex (VC) using immunocytochemistry, quantitative analysis, and confocal microscopy. As a diurnal animal, the Mongolian gerbil provides us with a different perspective to other commonly used nocturnal rodent models. In this study, SST neurons were located in all layers of the VC except in layer I; they were most common in layer V. Most SST neurons were multipolar round/oval or stellate cells. No pyramidal neurons were found. Moreover, 2-color immunofluorescence revealed that only 33.50%, 24.05%, 16.73%, 0%, and 64.57% of SST neurons contained gamma-aminobutyric acid, calbindin-D28K, calretinin, parvalbumin, and calcium/calmodulin-dependent protein kinase II, respectively. In contrast, neuropeptide Y and nitric oxide synthase were abundantly expressed, with 80.07% and 75.41% in SST neurons, respectively. Our immunocytochemical analyses of SST with D1 and D2 dopamine receptors and choline acetyltransferase, α7 and ß2 nicotinic acetylcholine receptors suggest that dopaminergic and cholinergic fibers contact some SST neurons. The results showed some distinguishable features of SST neurons and provided some insight into their afferent circuitry in the gerbil VC. These findings may support future studies investigating the role of SST neurons in visual processing.

4.
Folia Histochem Cytobiol ; 58(2): 61-72, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32490536

RESUMO

INTRODUCTION: In order to enhance our understanding of bat vision, we investigated tyrosine hydroxylase (TH)-immunoreactive (IR) fibers in the visual cortex of the microbat. MATERIAL AND METHODS: The study was conducted on 12 freshly-caught adult bats (Rhinolophus ferrumequinum, both sexes, weighing 15-20 g). We used standard immunocytochemistry and confocal microscopy. RESULTS: TH-IR fibers were distributed throughout all layers of the visual cortex, with the highest density in layer I. Two types of TH-IR fibers were observed: small and large varicose fibers. TH-IR cells were not found in the microbat visual cortex. The microbat substantia nigra and ventral tegmental areas, previously identified sources of TH-IR fibers in the mammalian visual cortex, all contained strongly labeled TH-IR cells. The average diameters of TH-IR cells in the substantia nigra and the ventral tegmental areas were 14.39 ± 0.13 µm (mean ± SEM) and 11.85 ± 0.13 µm, respectively. CONCLUSIONS: Our results suggest that the microbat has a well-constructed neurochemical organization of THIR fibers. This observation should provide fundamental insights into a better understanding of the nocturnal, echolocating bat visual system.


Assuntos
Tirosina 3-Mono-Oxigenase/metabolismo , Córtex Visual/ultraestrutura , Animais , Quirópteros , Feminino , Masculino , Neurônios/metabolismo , Córtex Visual/química
5.
Nutr Res Pract ; 13(4): 323-332, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31388409

RESUMO

BACKGROUND/OBJECTIVES: The aim of this study was to analyze specific foods influencing absolute nutrient intake and between-person variations of nutrient intake among Korean preschoolers. SUBJECTS/METHODS: This study included 2,766 participants aged 1-5 years in the 2009-2013 Korea National Health and Nutrition Examination Surveys. Dietary data were obtained from a 24-h dietary recall method. Major food sources of absolute nutrient intake were evaluated based on percent contribution of each food. To assess the contribution of specific foods to between-person variations in nutrient intake, stepwise multiple regressions were performed and cumulative R2 was used. RESULTS: White rice and milk were main food sources of energy, protein, carbohydrate, phosphorus, iron, potassium, thiamin, riboflavin, and niacin. The percentage of fat contributed by milk was 21.3% which was the highest, followed by pork, soybean oil, and egg. White rice accounted for 25% and 40% of total variability in total energy and carbohydrate intakes, respectively. About 39% of variation in calcium intake was explained by milk while 40% of variation in phosphorous intake was explained by cheese. The top 10 foods contributing to between-person variations in nutrient intakes were similar with food items that mainly contributed to absolute nutrient intakes. The number of foods explaining 90% of absolute amounts of nutrient intakes varied from 28 for vitamin A to 80 for iron. CONCLUSIONS: This study identified specific foods that contributed to absolute nutrient intakes and between-person variations in nutrient intakes among Korean preschoolers. Our findings can be used to develop dietary assessment tools and establish food-based dietary guidelines for young children.

6.
J Cell Biochem ; 120(6): 9810-9819, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30525244

RESUMO

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.


Assuntos
Movimento Celular/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 9 da Matriz/biossíntese , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Ácido Oleanólico/análogos & derivados , Saponinas/farmacologia , Animais , Neoplasias do Colo , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ácido Oleanólico/farmacologia
7.
J Cell Biochem ; 119(1): 1173-1182, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28708322

RESUMO

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.


Assuntos
Anti-Inflamatórios/farmacologia , Gangliosídeo G(M3)/farmacologia , Lipopolissacarídeos/efeitos adversos , Macrófagos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Macrófagos/química , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Fosforilação/efeitos dos fármacos , Células RAW 264.7 , Fator de Transcrição AP-1/metabolismo
8.
Oncotarget ; 8(42): 72205-72219, 2017 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-29069780

RESUMO

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.

9.
Int J Biol Sci ; 13(3): 265-275, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367091

RESUMO

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.


Assuntos
Gangliosídeos/farmacologia , Molécula 1 de Adesão Intercelular/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Sialiltransferases/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
PLoS One ; 12(2): e0171322, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28207754

RESUMO

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.


Assuntos
Anti-Inflamatórios/farmacologia , Mediadores da Inflamação/metabolismo , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
J Cell Biochem ; 118(8): 2168-2181, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28019668

RESUMO

Some sialic acid-containing glycolipids are known to regulate development of atherosclerosis with accumulated plasma apolipoprotein B-100 (Apo-B)-containing lipoproteins, because Apo-B as an atherogenic apolipoprotein is assembled mainly in VLDL and LDL. Previously, we have elucidated that disialyl GD3 promotes the microsomal triglyceride transfer protein (MTP) gene expression and secretion of triglyceride (TG)-assembled ApoB, claiming the GD3 role in ApoB lipoprotein secretion in liver cells. In the synthetic pathway of gangliosides, GD3 is synthesized by addition of a sialic acid residue to GM3. Thus, there should be some regulatory links between GM3 and GD3. In this study, exogenous and endogenous monosialyl GM3 has been examined how GM3 plays a role in ApoB secretion in Chang liver cells in a view point of MTP and ApoB degradation in the same cells. The level of GM3 ganglioside in the GM3 synthase gene-transfected cells was increased in the cell extract, but not in the medium. In addition, GM3 synthase gene-transfected cells showed a diminished secretion of TG-enriched ApoB with a lower content of TG in the medium. Exogenous GM3 treatment for 24 h exerted a dose dependent inhibitory effect on ApoB secretion together with TG, while a liver-specific albumin was unchanged, indicating that GM3 effect is limited to ApoB secretion. GM3 decreased the mRNA level of MTP gene, too. ApoB protein assembly dysregulated by GM3 indicates the impaired ApoB secretion is caused by a proteasome-dependent pathway. Treatment with small interfering RNAs (siRNAs) decreased ApoB secretion, but GM3-specific antibody did not. These results indicate that plasma membrane associated GM3 inhibits ApoB secretion, lowers development of atherosclerosis by decreasing the secretion of TG-enriched ApoB containing lipoproteins, suggesting that GM3 is an inhibitor of ApoB and TG secretion in liver cells. J. Cell. Biochem. 118: 2168-2181, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Apolipoproteína B-100/metabolismo , Gangliosídeo G(M3)/metabolismo , Fígado/metabolismo , Apolipoproteína B-100/genética , Western Blotting , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular , Colesterol/química , Gangliosídeo G(M3)/farmacologia , Gangliosídeos/metabolismo , Gangliosídeos/farmacologia , Células Hep G2 , Humanos , Imunoprecipitação , Fígado/efeitos dos fármacos , Ácido N-Acetilneuramínico/química , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sialiltransferases/genética , Sialiltransferases/metabolismo , Triglicerídeos/química
12.
Int J Mol Sci ; 17(5)2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27144558

RESUMO

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.


Assuntos
Apoptose/efeitos dos fármacos , Gangliosídeos/toxicidade , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caspase 7/metabolismo , Caspase 8/metabolismo , Inibidores de Caspase/farmacologia , Feminino , Galactosiltransferases/genética , Galactosiltransferases/metabolismo , Gangliosídeos/biossíntese , Humanos , Células MCF-7 , Microscopia de Fluorescência , Oligopeptídeos/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
13.
Enzyme Microb Technol ; 86: 117-26, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26992800

RESUMO

The family B DNA polymerase gene from the euryarchaeon Thermococcus barophilus Ch5 (Tba5) contains an open reading frame of 6198 base pairs that encodes 2065 amino acid residues. The gene is split by three inteins that must be spliced out to form the mature DNA polymerase. A Tba5 DNA polymerase gene without inteins (genetically intein-spliced) was expressed under the control of the pET-28b(+)T7lac promoter in E. coli Rosetta 2(DE3)pLysS cells. The molecular mass of the purified Tba5 DNA polymerase was about 90kDa consistent with the 90,470Da molecular mass calculated based on the 776 amino acid sequence. The optimal pH for Tba5 DNA polymerase activity was 7.5 and the optimal temperature was 70-75°C. The enzyme possessed 3'→5' exonuclease activity and was activated by magnesium ions. PCR amplification using Tba5 DNA polymerase enables high-yield for 1- to 6-kb target DNA products, while 8- to 10-kb target DNA products were amplified at low or inefficient levels. To simultaneously improve product yield and amplification fidelity, Tba5 plus DNA polymerase mixtures were constituted with various amounts of Tba5 DNA polymerase mixed with Taq DNA polymerase. The Tba5 plus DNA polymerase mixtures robustly amplified up to 25-kb λ DNA fragments. In addition, the PCR error rate of Tba5 plus3 and Tba5 plus4 mixtures were much lower than those of wild-type Tba5 DNA polymerase, Pfu DNA polymerase, Taq DNA polymerase, and Pfu plus DNA polymerase.


Assuntos
Proteínas Arqueais/química , Proteínas Arqueais/metabolismo , DNA Polimerase Dirigida por DNA/química , DNA Polimerase Dirigida por DNA/metabolismo , Reação em Cadeia da Polimerase/métodos , Thermococcus/enzimologia , Proteínas Arqueais/genética , Clonagem Molecular , DNA Polimerase Dirigida por DNA/genética , Genes Arqueais , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Thermococcus/genética
14.
Mar Drugs ; 13(6): 3936-49, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-26090845

RESUMO

For innate immune defense, lower animals such as fish and amphibian are covered with skin mucus, which acts as both a mechanical and biochemical barrier. Although several mucus sources have been isolated and studied for their biochemical and immunological functions, the precise mechanism(s) of action remains unknown. In the present study, we additionally found the eel skin mucus (ESM) to be a promising candidate for use in anti-tumor therapy. Our results showed that the viability of K562 cells was decreased in a dose-dependent manner by treatment with the isolated ESM. The cleaved forms of caspase-9, caspase-3 and poly adenosine diphosphate-ribose polymerase were increased by ESM. The levels of Bax expression and released cytochrome C were also increased after treatment with ESM. Furthermore, during the ESM mediated-apoptosis, phosphorylation levels of ERK1/2 and p38 but not JNK were increased and cell viabilities of the co-treated cells with ESM and inhibitors of ERK 1/2 or p38 were also increased. In addition, treatment with lactose rescued the ESM-mediated decrease in cell viability, indicating lactose-containing glycans in the leukemia cells acted as a counterpart of the ESM for interaction. Taken together, these results suggest that ESM could induce mitochondria-mediated apoptosis through membrane interaction of the K562 human leukemia cells. To the best of our knowledge, this is the first observation that ESM has anti-tumor activity in human cells.


Assuntos
Anguilla/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Muco/metabolismo , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Células K562 , Lactose/metabolismo , Leucemia/tratamento farmacológico , Leucemia/patologia , Mitocôndrias/metabolismo , Polissacarídeos/metabolismo , Pele/metabolismo
15.
Biochem J ; 449(1): 241-51, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23050851

RESUMO

TGF-ß (transforming growth factor-ß)-induced EMT (epithelial-mesenchymal transition) induces the proliferation and migration of the HLE (human lens epithelial) cells. Ganglioside GM3, simple sialic-acid-containing glycosphingolipids on mammalian cell membranes, regulates various pathological phenomena such as insulin resistance and tumour progression. However, the relationship between ganglioside GM3 and TGF-ß-induced EMT in the HLE B-3 cells is poorly understood. In the present study we demonstrated that ganglioside GM3 was involved in TGF-ß1-induced EMT in HLE B-3 cells. Our results indicated that the expression of ganglioside GM3 and GM3 synthase mRNA were significantly increased in TGF-ß1-induced HLE B-3 cells. Reporter gene analysis also demonstrated that transcriptional activation of the GM3 synthase gene was regulated by Sp1 (specificity protein 1) in HLE B-3 cells upon TGF-ß1 stimulation. Interestingly, the inhibition of ganglioside GM3 expression by d-PDMP [d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol] and GM3 synthase shRNA (short hairpin RNA) resulted significantly in the suppression of cell migration and EMT-related signalling in HLE B-3 cells stimulated by TGF-ß. Furthermore, exogenous treatment of ganglioside GM3 rescued the expression of EMT molecules and cell migration suppressed by the depletion of ganglioside GM3 in TGF-ß1-induced HLE B-3 cells. We also found that ganglioside GM3 interacted with TGFßRs (TGF-ß receptors) in TGF-ß1-induced HLE B-3 cells. Taken together, these results suggest that ganglioside GM3 induced by TGF-ß1 regulates EMT by potential interaction with TGFßRs.


Assuntos
Movimento Celular/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Cristalino/citologia , Cristalino/metabolismo , Sialiltransferases/química , Fator de Crescimento Transformador beta1/fisiologia , Sequência de Bases , Linhagem Celular , Células Epiteliais/metabolismo , Humanos , Mesoderma/metabolismo , Dados de Sequência Molecular , Sialiltransferases/fisiologia , Fator de Crescimento Transformador beta1/química
16.
Biol Pharm Bull ; 35(6): 938-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22687535

RESUMO

Citreorosein (CIT), an anthraquinone component of Polygoni cuspidati (P. cuspidati) radix, suppressed gene expression of proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß in mouse bone marrow-derived mast cells (BMMCs) stimulated with phorbol 12-myristate 13-acetate (PMA) plus the calcium ionophore A23187. To investigate the molecular mechanisms underlying CIT inhibition of the pro-inflammatory cytokine production, its effects on the activation of both nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) were assessed. CIT attenuated phosphorylation of the MAPKs including extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAP kinase and c-Jun NH(2)-terminal kinase (JNK). Furthermore, CIT strongly inhibited DNA binding activity of NF-κB through the inhibition of phosphorylation and degradation of inhibitor of kappaB (IκB) as well as activator protein-1 (AP)-1 through the reduction of phosphorylation of c-Jun. These results demonstrate that CIT inhibits proinflammatory cytokines production through the inhibition of both MAPKs and AKT-mediated IκB kinase (IKK) phosphorylation and subsequent inhibition of transcription factor NF-κB activation, thereby attenuating the production of proinflammatory cytokines.


Assuntos
Antraquinonas/farmacologia , Anti-Inflamatórios/farmacologia , Citocinas/antagonistas & inibidores , Mastócitos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Animais , Células da Medula Óssea/citologia , Células Cultivadas , Citocinas/metabolismo , Masculino , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fator de Transcrição AP-1/antagonistas & inibidores , Fator de Transcrição AP-1/metabolismo
17.
Inflammation ; 35(2): 736-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21845471

RESUMO

Extracellular matrix-degrading protease, matrix metalloproteinase-9 (MMP-9), is known to be involved in vascular smooth muscle cell (SMC)'s aberrant proliferation and movement in atherosclerotic lesions. During screening of the MMP-9-inhibitory compounds from marine animal resources, we have found that the ethyl acetate extract from Cliona celata (ECC) effectively inhibits the SMC-derived MMP-9 enzyme activity and gene expression. In addition, the ECC effectively repressed the migration potential of the tumor necrosis factor-α (TNF-α)-stimulated human aortic smooth muscle cell (HASMC). As assessed by Western blot analysis, the produced MMP-9 protein levels in the TNF-α-induced HASMC were significantly decreased by the concomitant treatment of ECC at the 50- to 300-µg/mL concentration ranges. In addition, in the RT-PCR experiment, the expressed MMP-9 mRNA levels in the TNF-α-induced HASMC were seemingly decreased by ECC treatment at the same concentration ranges (50-300 µg/mL). For the action mechanism(s) of ECC to the phenotype changes in HASMC, we have further evaluated the ECC's pharmacological activities on the signal molecules which are importantly linked in the MMP-9 expression and cell migration potential of HASMC. We have found that extracellular signal-regulated kinase 1 and 2 (ERK1/2) phosphorylation as a target point is suppressed by the ECC treatment in the TNF-α-treated HASMC. Using electrophoretic mobility shift assay, the nuclear extracts purified from ECC-treated HASMCs were shown to decrease the binding potentials on the labeled nuclear factor-kappaB (NF-κB) and activator protein 1 probes. NF-κB p65 and phosphorylated c-Jun contents were also decreased in the purified nuclear extracts from the ECC-treated HASMC, as confirmed by Western blot analysis. Finally, it was shown that the ECC-treated HASMCs were less migrated when compared to the TNF-α-treated cells, as confirmed by HASMC migration assays using the 8-µm pore transwell membranes. From these results, it was proposed that ECC has a potentially applicable anti-atherosclerotic activity.


Assuntos
Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Poríferos , Fator de Transcrição AP-1/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Regulação para Baixo , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Int Immunopharmacol ; 12(1): 175-81, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22155103

RESUMO

Saucerneol F (SF), a new tetrahydrofuran-type sesquilignan isolated from Saururus chinensis, dose-dependently inhibited nitric oxide (NO) production, with concomitant reduction of inducible nitric oxide synthase (iNOS) protein and mRNA expression in lipopolysaccharide (LPS)-stimulated murine macrophage RAW264.7 cells. To elucidate the molecular mechanism underlying the inhibition of iNOS expression by SF, we assessed the effects of SF on nuclear factor-κB (NF-κB) DNA-binding activity, NF-κB-dependent reporter gene activity, inhibitory factor-κB (IκB) phosphorylation and degradation, and p65 nuclear translocation. Treatment with SF decreased the luciferase activities of NF-κB reporter promoters in a dose-dependent manner and translocation of NF-κB p65. In addition, pretreatment of SF reduced LPS-stimulated activation of mitogen-activated protein kinases (MAPKs) including extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAPK, and c-Jun NH(2)-terminal kinase (JNK). Furthermore, SF attenuated the luciferase activities of AP-1 reporter promoters and the DNA-binding capacity of AP-1. Taken together, the present results indicate that SF attenuates NO production and iNOS expression by blocking LPS-induced activation of NF-κB, MAPKs, and AP-1, suggesting that SF is potentially applicable as an anti-inflammatory drug.


Assuntos
Anti-Inflamatórios/farmacologia , Lignanas/farmacologia , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Animais , Linhagem Celular , Quinase I-kappa B/metabolismo , Lipopolissacarídeos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , RNA Mensageiro/metabolismo , Saururaceae , Fator de Transcrição AP-1/metabolismo
19.
J Womens Health (Larchmt) ; 20(6): 963-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21671781

RESUMO

UNLABELLED: Abstract Background: Chronic inflammation and oxidative stress are associated with the development of metabolic syndrome (MetS). Bilirubin is an antioxidant and has a protective effect against cardiovascular disease (CVD). The purpose of this study was to examine the association between total bilirubin levels and the prevalence of MetS in rural Korean women. METHODS: This cross-sectional study included 5,266 women (>40 years) enrolled in the Korean Genomic Rural Cohort (KGRC). MetS was defined using the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) guidelines. Total bilirubin levels were categorized into quartiles. RESULTS: Subjects in the upper quartiles of total bilirubin were younger and had lower waist circumferences, systolic blood pressure, and triglyceride levels and higher high-density lipoprotein cholesterol (HDL-C) concentrations. The overall prevalence of MetS was 39.0%. When the participants were categorized into quartiles by total bilirubin level, the prevalence of MetS according to increasing total bilirubin quartiles was 47.9%, 41.2%, 34.3%, and 32.7%, respectively. By comparison to the lowest quartile of total bilirubin (<0.61 mg/dL), the odds ratio (OR) (95% confidence interval [CI]) for MetS in the highest quartile of total bilirubin (≥0.94 mg/dL) was 0.63 (0.52-0.77) after adjusting for menopausal status, C-reactive protein (CRP) levels, insulin resistance, and other covariates. CONCLUSIONS: Total bilirubin level appears to be inversely associated with the prevalence of MetS in rural Korean women >40 years of age in the KGRC, even after adjusting for risk factors of MetS, including body mass index (BMI), menopausal status, CRP levels, and homeostasis model assessment of insulin resistance (HOMA-IR).


Assuntos
Bilirrubina/sangue , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Adulto , Idoso , Análise de Variância , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Fatores de Risco , População Rural
20.
Toxicol In Vitro ; 25(4): 767-73, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21276846

RESUMO

Atherosclerosis is accompanied by the proliferation of human aortic smooth muscle cells (HASMC) and their movement into the intima. Many reports have indicated the involvement of gelatinases (MMP-9 and MMP-2) in this pathogenesis. The ethylacetate fraction from starfish, Asterias amurensis (EFA), harvested from the Korean seaside has an inhibitory effect on MMP-9 and MMP-2 activities, as well as on the expression of MMP-9 in TNF-α induced HASMC in a dose-dependent manner. Also, EFA inhibits the migration of TNF-α induced HASMC in transwells containing gelatin coated plugs. EFA was not cytotoxic to HASMC over the range 0-1mg/ml. By Western-blot analysis, it was revealed that the phosphorylation of extracellular signal regulated kinase (ERK) in TNF-α induced cells was inhibited and nuclear factor kappa B (NF-κB) p65 levels in nuclear extracts were decreased by EFA treatment. In addition, ERK inhibitor (U0126) treated cells exhibited decreased MMP-9 activity in the zymographic assay. From these results, it was found that the gelatinolytic activity was regulated (1) by enzymatic inhibition of both MMP-9 and MMP-2, as well as (2) by the decreased production of MMP-9 via ERK pathways in EFA treated HASMCs. Taken together, it has been shown that EFA has a putative anti-atherosclerotic effect.


Assuntos
Asterias/química , Inibidores de Metaloproteinases de Matriz , Miócitos de Músculo Liso/efeitos dos fármacos , Acetatos/química , Animais , Aorta/citologia , Aorta/efeitos dos fármacos , Aorta/metabolismo , Western Blotting , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Coreia (Geográfico) , Miócitos de Músculo Liso/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
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