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1.
JACS Au ; 1(8): 1198-1207, 2021 Aug 23.
Article in English | MEDLINE | ID: mdl-34467358

ABSTRACT

Metal-organic frameworks (MOFs) are a class of microporous materials that have been highlighted with fast and selective sorption of gas molecules; however, they are at least partially unstable in the scale-up process. Here, we report a rational shaping of MOFs in a scalable architecture of fiber sorbent. The long-standing stability challenge of MOFs was resolved by using stable metal oxide precursors that are subject to controlled surface oxide dissolution-growth chemistry during the Mg-based MOF synthesis. Highly uniform MOF crystals are synthesized along with the open-porous fiber sorbents networks, showing unprecedented cyclic CO2 capacities in both flue gas and direct air capture (DAC) conditions. The same chemistry enables an in situ flow synthesis of Mg-MOF fiber sorbents, providing a scalable pathway for MOF synthesis in an inert condition with minimal handling steps. This modular approach can serve both as a reaction stage for enhanced MOF fiber sorbent synthesis and as a "process-ready" separation device.

2.
Cancer Sci ; 111(9): 3292-3302, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32644283

ABSTRACT

EphA10 (erythropoietin-producing hepatocellular carcinoma receptor A10) is a catalytically defective receptor protein tyrosine kinase in the ephrin receptor family. Although EphA10 is involved in the malignancy of some types of cancer, its role as an oncogene has not been extensively studied. Here, we investigated the influence of EphA10 on the tumorigenic potential of pancreatic cancer cells. Analysis of expression profiles from The Cancer Genome Atlas confirmed that EphA10 was elevated and higher in tumor tissues than in normal tissues in some cancer types, including pancreatic cancer. EphA10 silencing reduced the proliferation, migration, and adhesion of MIA PaCa-2 and AsPC-1 pancreatic cancer cells. These effects were reversed by overexpression of EphA10 in MIA PaCa-2 cells. Importantly, overexpression and silencing of EphA10 respectively increased and decreased the weight, volume, and number of Ki-67-positive proliferating cells in MIA PaCa-2 xenograft tumors. Further, EphA10 expression was positively correlated with invasion and gelatin degradation in MIA PaCa-2 cells. Moreover, overexpression of EphA10 enhanced the expression and secretion of MMP-9 in MIA PaCa-2 cells and increased the expression of MMP-9 and the vascular density in xenograft tumors. Finally, expression of EphA10 increased the phosphorylation of ERK, JNK, AKT, FAK, and NF-κB, which are important for cell proliferation, survival, adhesion, migration, and invasion. Therefore, we suggest that EphA10 plays a pivotal role in the tumorigenesis of pancreatic epithelial cells and is a novel therapeutic target for pancreatic cancer.


Subject(s)
Carcinogenesis/genetics , Carcinogenesis/metabolism , Disease Susceptibility , Pancreatic Neoplasms/etiology , Pancreatic Neoplasms/metabolism , Receptors, Eph Family/genetics , Receptors, Eph Family/metabolism , Animals , Cell Adhesion , Cell Line, Tumor , Cell Movement , Cell Proliferation , Disease Models, Animal , Gene Knockdown Techniques , Heterografts , Humans , Matrix Metalloproteinase 9/metabolism , Mice , Pancreatic Neoplasms/pathology , Signal Transduction
3.
Materials (Basel) ; 12(16)2019 Aug 14.
Article in English | MEDLINE | ID: mdl-31416249

ABSTRACT

This research objective was to determine the significant parameters for effective plasma assisted machining (PAM) of Ti-6Al-4V and to derive optimal processing conditions. PAM parameters such as feed rate, spindle speed, and depth of cut have significant effects on its machining characteristic. In this study, the design of experiments (DOE) was used to select optimal machining conditions for PAM. The signal-to-noise (S/N) ratio was analyzed using the Taguchi method and the contributions of the factors were determined using analysis of variance (ANOVA). Finally, the optimal PAM machining conditions were selected using response optimization. In addition, the energy efficiency of conventional machining (CM) and the PAM were compared. The energy efficiency was analyzed by specific cutting energy. The cutting force and surface roughness of PAM decreased by 60.2% and 70.5%, respectively, in optimal PAM machining conditions.

4.
Int J Mol Sci ; 20(11)2019 Jun 04.
Article in English | MEDLINE | ID: mdl-31167359

ABSTRACT

Skullcapflavone II is a flavonoid derived from the root of Scutellaria baicalensis, a herbal medicine used for anti-inflammatory and anti-cancer therapies. We analyzed the effect of skullcapflavone II on the expression of matrix metalloproteinase-1 (MMP-1) and integrity of type I collagen in foreskin fibroblasts. Skullcapflavone II did not affect the secretion of type I collagen but reduced the secretion of MMP-1 in a dose- and time-dependent manner. Real-time reverse transcription-PCR and reporter gene assays showed that skullcapflavone II reduced MMP-1 expression at the transcriptional level. Skullcapflavone II inhibited the serum-induced activation of the extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) signaling pathways required for MMP-1 transactivation. Skullcapflavone II also reduced tumor necrosis factor (TNF)-α-induced nuclear factor kappa light chain enhancer of activated B cells (NF-κB) activation and subsequent MMP-1 expression. In three-dimensional culture of fibroblasts, skullcapflavone II down-regulated TNF-α-induced MMP-1 secretion and reduced breakdown of type I collagen. These results indicate that skullcapflavone II is a novel biomolecule that down-regulates MMP-1 expression in foreskin fibroblasts and therefore could be useful in therapies for maintaining the integrity of extracellular matrix.


Subject(s)
Collagen Type I/metabolism , Fibroblasts/drug effects , Fibroblasts/metabolism , Flavonoids/pharmacology , Matrix Metalloproteinase 1/genetics , Transcription, Genetic/drug effects , Biomarkers , Cells, Cultured , Humans , Matrix Metalloproteinase 1/metabolism , NF-kappa B/metabolism , Proteolysis/drug effects , Skin , Transcription Factor AP-1/metabolism , Tumor Necrosis Factor-alpha/metabolism
5.
J Nanosci Nanotechnol ; 19(3): 1609-1614, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30469231

ABSTRACT

In this study, we prepared cobalt-manganese (oxy) hydroxide nanosheets assembled structure covered of reduced graphene oxide hybrid structure (Co-Mn (O)OH NAS@rGO HS) via reduction and hydroxylation of Mn1.5Co1.5[Co(CN)6]2@graphene oxide (GO). Obtained precursors were optimized at 15 mg GO, and these are hybrid structures in which nanocubes 200-400 nm in size were fully covered by multi-layered GO. The functional group (-COOH, -OH, C-O-C) of GO was removed through reduction by L-ascorbic acid. We obtained MnCOOH, Co(OH)2, and Co-Mn LDH synthesized by hydroxylation of Mn1.5Co1.5[Co(CN)6]2@GO via ion exchange between the CN group and OH-. The hybrid nanostructure between transition-metal oxide/hydroxide and reduced graphene oxide could be used in various fields, including lithium ion batteries, supercapacitors, and electrocatalyst for water splitting.

6.
Biochem J ; 474(22): 3719-3732, 2017 11 01.
Article in English | MEDLINE | ID: mdl-28972070

ABSTRACT

Syndecans (SDCs) are transmembrane proteoglycans that are involved in cell adhesion and cell communication. Specifically, SDC2 plays a key role in tumorigenesis, metastasis, and angiogenesis. Previously, we found that rat SDC2 is shed by matrix metalloproteinase-7 (MMP-7) in colon cancer cells. Here, we analyzed the susceptibility of rat SDC2 to various MMPs. We found that the rat SDC2 ectodomain (ECD) fused to the C-terminal Fc region, which was expressed in mammalian cells, was cleaved more efficiently by MMP-14 than MMP-7. Likewise, when anchored on the surface of HeLa cells, rat SDC2 was cleaved more efficiently by the treatment of MMP-14 than MMP-7 and was shed more readily by membrane-anchored MMP-14 than soluble MMP-14. Furthermore, MMP-14 cleaved recombinant SDC2-ECD expressed in Escherichia coli into multiple fragments. Using N-terminal amino acid sequencing and the top-down proteomics approach, we determined that the major cleavage sites were S88↓L89, T98↓M99, T100↓L101, D132↓P133, and N148↓L149 for rat SDC2-ECD and S55↓G56, S65↓P66, P75↓K76, N92↓I93 D122↓P123, and S138↓L139 for human SDC2-ECD. Finally, the rat and human SDC2-ECD lost the ability to suppress vascular endothelial growth factor-induced formation of capillary-like tubes by human umbilical vein endothelial cells following cleavage by MMP-14, but its major cleavage-site mutant of rat SDC2-ECD did not. These results suggest that MMP-14 is a novel enzyme responsible for degrading SDC2 and impairing its physiological roles including angiogenesis.


Subject(s)
Human Umbilical Vein Endothelial Cells/physiology , Matrix Metalloproteinase 14/metabolism , Matrix Metalloproteinase 14/pharmacology , Syndecan-2/biosynthesis , Vascular Endothelial Growth Factor A/pharmacology , Animals , COS Cells , Chlorocebus aethiops , Dose-Response Relationship, Drug , HeLa Cells , Human Umbilical Vein Endothelial Cells/drug effects , Humans , Insecta , Rats
7.
J Biol Chem ; 292(39): 16321-16332, 2017 09 29.
Article in English | MEDLINE | ID: mdl-28821612

ABSTRACT

The syndecan family of heparan sulfate proteoglycans contributes to cell adhesion and communication by serving as co-receptors for cell signaling and extracellular matrix molecules. Syndecan-2 is located at the cell surface, and we previously reported that it induces matrix metalloproteinase-7 (MMP-7) expression in colon cancer cells. However, the underlying regulatory mechanisms are unknown. Here, we report that overexpression of syndecan-2 in HT-29 colon cancer cells increases the phosphorylation of focal adhesion kinase (FAK) and ERK in parallel with up-regulated MMP-7 expression, but a syndecan-2 mutant lacking the cytoplasmic domain showed significant reductions in these effects. Consistent with this observation, FAK inhibition via FAK-related non-kinase expression or inhibition of ERK with the ERK1/2 inhibitor SCH772984 diminished the syndecan-2-mediated up-regulation of MMP-7. Activation of PKC enhanced syndecan-2-mediated MMP-7 expression, whereas inhibition of PKC had the opposite effect. Of note, the exogenous expression of syndecan-2 triggered localization of PKCγ to the membrane. Expression of syndecan-2 harboring a phosphomimetic (S198E) mutation of the variable region of the cytoplasmic domain enhanced MMP-7 expression and FAK phosphorylation. Finally, experimental suppression of shedding of the syndecan-2 extracellular domain did not significantly affect the syndecan-2-mediated up-regulation of MMP-7 in the early period after syndecan-2 overexpression. Taken together, these findings suggest that syndecan-2's cytoplasmic domain up-regulates MMP-7 expression in colon cancer cells via PKCγ-mediated activation of FAK/ERK signaling.


Subject(s)
Carcinoma/metabolism , Colonic Neoplasms/metabolism , Focal Adhesion Kinase 1/metabolism , MAP Kinase Signaling System , Protein Kinase C/metabolism , Protein Processing, Post-Translational , Syndecan-2/metabolism , Amino Acid Substitution , Animals , Carcinoma/drug therapy , Carcinoma/enzymology , Colonic Neoplasms/drug therapy , Colonic Neoplasms/enzymology , Enzyme Induction/drug effects , Focal Adhesion Kinase 1/chemistry , Focal Adhesion Kinase 1/genetics , Humans , MAP Kinase Signaling System/drug effects , Matrix Metalloproteinase 7/genetics , Matrix Metalloproteinase 7/metabolism , Mutation , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/chemistry , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/chemistry , Peptide Fragments/genetics , Peptide Fragments/metabolism , Phosphorylation/drug effects , Protein Interaction Domains and Motifs , Protein Kinase Inhibitors/pharmacology , Protein Processing, Post-Translational/drug effects , RNA Interference , Rats , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Syndecan-2/antagonists & inhibitors , Syndecan-2/chemistry , Syndecan-2/genetics
8.
J Cell Biochem ; 118(9): 2887-2895, 2017 09.
Article in English | MEDLINE | ID: mdl-28214294

ABSTRACT

Protein tyrosine kinase 6 (PTK6; also known as Brk) is closely related to the Src family kinases, but lacks a membrane-targeting myristoylation signal. Sublocalization of PTK6 at the plasma membrane enhances its oncogenic potential. To understand the mechanism(s) underlying the oncogenic property of plasma---membrane-associated PTK6, proteins phosphorylated by membrane-targeted myristoylated PTK6 (Myr-PTK6) were enriched and analyzed using a proteomics approach. Eps8 which was identified by this method is phosphorylated by Myr-PTK6 in HEK293 cells. Mouse Eps8 expressed in HEK293 cells is phosphorylated by Myr-PTK6 at residues Tyr497, Tyr524, and Tyr534. Compared to wild-type Eps8 (Eps8 WT), the phosphorylation-defective 3YF mutant (Eps8 3YF) reverts the increased proliferation, migration, and phosphorylation of ERK and FAK mediated by Eps8 WT in HEK293 cells overexpressing PTK6. PTK6 knockdown in T-47D breast cancer cells decreased EGF-induced phosphorylation of Eps8. Endogenous PTK6 phosphorylates ectopically expressed Eps8 WT, but not Eps8 3YF mutant, in EGF-stimulated T-47D cells. The EGF-induced Eps8 phosphorylation enhances activation of ERK and FAK, cell adhesion, and anchorage-independent colony formation in T-47D cells, but not in the PTK6-knokdown T-47D cells. These results indicate that plasma-membrane-associated PTK6 phosphorylates Eps8, which promotes cell proliferation, adhesion, and migration and, thus, tumorigenesis. J. Cell. Biochem. 118: 2887-2895, 2017. © 2017 Wiley Periodicals, Inc.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Cell Membrane/metabolism , Cell Movement , Cell Proliferation , Mutation, Missense , Neoplasm Proteins/metabolism , Protein-Tyrosine Kinases/metabolism , Adaptor Proteins, Signal Transducing/genetics , Amino Acid Substitution , Cell Line, Tumor , Cell Membrane/genetics , Female , HEK293 Cells , Humans , Neoplasm Proteins/genetics , Phosphorylation/genetics , Protein-Tyrosine Kinases/genetics
9.
Biomol Ther (Seoul) ; 25(2): 122-129, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28173643

ABSTRACT

A diversity of synthetic cathinones has flooded the recreational drug marketplace worldwide. This variety is often a response to legal control actions for one specific compound (e.g. methcathinone) which has resulted in the emergence of closely related replacement. Based on recent trends, the nitrogen atom is one of the sites in the cathinone molecule being explored by designer type modifications. In this study, we designed and synthesized two new synthetic cathinones, (1) α-piperidinopropiophenone (PIPP) and (2) α-piperidinopentiothiophenone (PIVT), which have piperidine ring substituent on their nitrogen atom. Thereafter, we evaluated whether these two compounds have an abuse potential through the conditioned place preference (CPP) in mice and self-administration (SA) in rats. We also investigated whether the substances can induce locomotor sensitization in mice following 7 days daily injection and challenge. qRT-PCR analyses were conducted to determine their effects on dopamine-related genes in the striatum. PIPP (10 and 30 mg/kg) induced CPP in mice, but not PIVT. However, both synthetic cathinones were not self-administered by the rats and did not induce locomotor sensitization in mice. qRT-PCR analyses showed that PIPP, but not PIVT, reduced dopamine transporter gene expression in the striatum. These data indicate that PIPP, but not PIVT, has rewarding effects, which may be attributed to its ability to affect dopamine transporter gene expression. Altogether, this study suggests that PIPP may have abuse potential. Careful monitoring of this type of cathinone and related drugs are advocated.

10.
Pharmacol Biochem Behav ; 153: 160-167, 2017 02.
Article in English | MEDLINE | ID: mdl-28063946

ABSTRACT

The recreational use of synthetic cathinones has dramatically increased in recent years, which is partly due to easy accessibility and ability of synthetic cathinones to exert rewarding effects similar to cocaine and methamphetamine. Many synthetic cathinones have already been scheduled in several countries; however, novel and diverse synthetic cathinones are emerging at an unprecedented rate, often outpacing regulatory processes. Recently, designer modifications of the basic cathinone molecule are usually performed on the alpha-carbon position. In this study, we designed and synthesized two novel synthetic cathinones with substituents on alpha-carbon position, [1] 2-cyclohexyl-2-(methylamino)-1-phenylethanone (MACHP), and [2] 2-(methylamino)-1-phenyloctan-1-one (MAOP). Then, we evaluated their rewarding and reinforcing effects through the conditioned place preference (CPP) in mice and self-administration (SA) test in rats. Locomotor activity was also assessed in mice during daily MACHP or MAOP treatment for 7days and drug challenge. qRT-PCR analyses were conducted to determine their effects on dopamine-related genes in the striatum. MACHP and MAOP produced CPP at 10 and 30mg/kg. In the SA test, MACHP (1mg/kg/infusion), but not MAOP, was self-administered. Both MACHP and MAOP induced locomotor sensitization in mice. qRT-PCR analyses showed that MACHP and MAOP reduced dopamine transporter gene expression in the striatum. These data indicate that MACHP and MAOP may have rewarding properties, which might be attributed to their ability to affect the dopaminergic activity. These findings may be useful in predicting the abuse potential and hasten the regulation of future cathinone entities with similar modifications.


Subject(s)
Alkaloids/pharmacology , Dopaminergic Neurons/drug effects , Substance-Related Disorders , Animals , Conditioning, Psychological/drug effects , Dopamine Plasma Membrane Transport Proteins/genetics , Male , Mice , Mice, Inbred ICR , Motor Activity/drug effects , Rats , Rats, Sprague-Dawley , Reward , Self Administration
11.
J Food Sci ; 82(2): 341-349, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28099767

ABSTRACT

Strawberry (Fragaria ananassa Duch.) possesses good antioxidant properties. Phenolic compounds in strawberries, such as anthocyanins and ellagic acid, mainly act as antioxidants. This study aimed to compare the phenolic content and expression patterns of genes involved in flavonoid biosynthesis between summer and winter strawberry cultivars affected by seasonal variation, degree of ripeness, and genotype. Antioxidant activity and the total content of phenols and flavonoids decreased with fruit ripening. Most notably, summer strawberry cultivars showed higher antioxidant activity than winter cultivars. The expression patterns of flavonoid biosynthetic genes tested were cultivar-dependent and were also affected by ripening. These results help us understand the nutritional and physiological characteristics of selected cultivars and provide a range of information for strawberry consumption.


Subject(s)
Antioxidants/metabolism , Flavonoids/biosynthesis , Fragaria/metabolism , Phenols/metabolism , Plant Proteins/genetics , Antioxidants/analysis , Flavonoids/analysis , Fragaria/chemistry , Fragaria/classification , Fragaria/genetics , Fruit/chemistry , Gene Expression Regulation, Plant , Genotype , Phenols/analysis , Plant Proteins/metabolism , Seasons
12.
Behav Brain Res ; 317: 494-501, 2017 01 15.
Article in English | MEDLINE | ID: mdl-27737791

ABSTRACT

The recreational use of synthetic cathinones has grown rapidly which prompted concerns from legal authorities and health care providers. However, in response to legislative regulations, synthesis of novel synthetic cathinones by introducing substituents in cathinone molecule has dramatically increased the diversity of these substances. Based on current trends, the aromatic ring is one of the popular sites in cathinone molecule being explored by designer-type modifications. In this study, we designed and synthesized a novel synthetic cathinone, 2-(methylamino)-1-(naphthalen-2-yl) propan-1-one (BMAPN), which has a naphthalene substituent on the aromatic ring. Thereafter, we determined whether BMAPN has rewarding and reinforcing effects through the conditioned place preference (CPP) test in mice and self-administration (SA) paradigm in rats. Locomotor sensitization was also assessed in mice during daily BMAPN treatment for 7days and drug challenge. Furthermore, we investigated the effects on BMAPN on dopamine-related genes in the striatum of mice using quantitative real-time polymerase chain reaction (qRT-PCR). BMAPN induced CPP at 10 and 30mg/kg and was modestly self-administered at 0.3mg/kg/infusion. Repeated BMAPN (30mg/kg) administration also produced locomotor sensitization. qRT-PCR analyses revealed decreased dopamine transporter and increased dopamine receptor D2 gene expression in the striatum of the BMAPN-treated mice. These data indicate that BMAPN has rewarding and reinforcing properties, which might be due to its effects on dopamine-related genes. The present study suggests that these findings may be useful in predicting abuse potential of future cathinone entities with aromatic ring substitutions.


Subject(s)
Alkaloids/pharmacology , Conditioning, Operant/drug effects , Corpus Striatum/drug effects , Dopamine/metabolism , Reward , Alkaloids/chemistry , Animals , Dopamine/genetics , Dopamine Agents/pharmacology , Dose-Response Relationship, Drug , Locomotion/drug effects , Magnetic Resonance Imaging , Male , Methamphetamine/pharmacology , Mice , Mice, Inbred ICR , Rats , Rats, Sprague-Dawley , Receptors, Dopamine/genetics , Receptors, Dopamine/metabolism , Self Administration , Tritium , Tyrosine 3-Monooxygenase/genetics , Tyrosine 3-Monooxygenase/metabolism
13.
Neurochem Int ; 100: 146-158, 2016 11.
Article in English | MEDLINE | ID: mdl-27623093

ABSTRACT

Para-methoxymethamphetamine (PMMA) is a para-ring-substituted amphetamine derivative sold worldwide as an illegal psychotropic drug. Although PMMA use has been reported to lead to severe intoxication and even death, little is known about the mechanism(s) by which PMMA exerts its neurotoxic effects. Here we found that PMMA treatment resulted in phosphorylation of protein kinase Cδ (PKCδ) and subsequent mitochondrial translocation of cleaved PKCδ. PMMA-induced oxidative stress was more pronounced in mitochondria than in the cytosol. Moreover, treatment with PMMA consistently resulted in significant reductions in mitochondrial membrane potential, mitochondrial complex I activity, and mitochondrial Mn superoxide dismutase-immunoreactivity. In contrast, PMMA treatment led to a significant increase in intramitochondrial Ca2+ level. Treatment with PMMA also significantly increased ionized calcium binding adaptor molecule 1 (Iba-1)-labeled microglial activation and upregulated tumor necrosis factor alpha (TNF-α) gene expression. PKCδ knockout attenuated these mitochondrial effects and dampened the neurotoxic effects of PMMA. Importantly, TNF-α knockout mice were significantly protected from PMMA-induced increases in phospho-PKCδ expression, mitochondrial translocation of cleaved PKCδ, and Iba-1-labeled microgliosis. Both rottlerin, a pharmacological inhibitor of PKCδ, and etanercept, a pharmacological inhibitor of TNF-α, significantly protected against PMMA-mediated induction of apoptosis, as assessed by terminal deoxynucleotidyl transferase dUDP nick end labeling (TUNEL) assays. In addition, PKCδ knockout and TNF-α knockout both resulted in decreased PMMA-mediated induction of dopaminergic loss. Therefore, our results suggest that PKCδ mediates PMMA-induced neurotoxicity by facilitating oxidative stress (mitochondria > cytosol), mitochondrial dysfunction, microglial activation, and pro-apoptotic signaling. Our results also indicate that PMMA-induced PKCδ activation requires the proinflammatory cytokine TNF-α.


Subject(s)
Corpus Striatum/drug effects , Methamphetamine/pharmacology , Mitochondria/drug effects , Protein Kinase C-delta/metabolism , Stress, Physiological/drug effects , Animals , Apoptosis/drug effects , Corpus Striatum/metabolism , Cytosol/metabolism , Dopamine/metabolism , Membrane Potential, Mitochondrial/drug effects , Mice, Knockout , Mitochondria/metabolism , Neurotoxicity Syndromes/metabolism , Protein Kinase C-delta/deficiency
14.
Bioorg Med Chem Lett ; 26(17): 4170-3, 2016 09 01.
Article in English | MEDLINE | ID: mdl-27503682

ABSTRACT

Baicalein is a well-known flavone derivative that possesses diverse biological properties, such as anticancer, antioxidant and anti-inflammatory activities. Numerous baicalein derivatives, including 5,6,7-trimethoxyflavone, have been synthesized with the aim of enhancing its inherent biological activities. In the present work, new flavones, possessing an N-aroylamine-substituent on the B-ring, were synthesized to improve the cytotoxicity of baicalein and 5,6,7-trimethoxyflavone against human cancer cell lines. The majority of the flavones synthesized exhibited greater cytotoxicity than baicalein and 5,6,7-trimethoxyflavone against HepG2 and MCF-7 cells. Among them, compounds 5n, possessing a 3-methoxybenzoylamino group, exhibited great cytotoxic effects on HepG2 (GI50=7.06µM) and MCF-7 (GI50=7.67µM) cells. In contrast, N-aroylamine-substituted 5-hydroxy-6,7-dimethoxyflavone derivatives showed greater cytotoxicity against MCF-7 than HepG2 cells, indicating that the replacement of a 5-methoxy group on the A-ring with a 5-hydroxy group has a marked influence on the cytotoxicity profile.


Subject(s)
Antineoplastic Agents/chemical synthesis , Benzamides/chemistry , Flavones/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/toxicity , Cell Survival/drug effects , Flavanones/chemistry , Flavones/chemical synthesis , Flavones/toxicity , Flavonoids/chemistry , Flavonoids/toxicity , Hep G2 Cells , Humans , MCF-7 Cells , Neoplasms , Structure-Activity Relationship
15.
Behav Brain Res ; 311: 403-407, 2016 09 15.
Article in English | MEDLINE | ID: mdl-27265782

ABSTRACT

Methiopropamine (MPA) is a structural analog to methamphetamine and is categorized as a novel psychoactive substance that needs to be controlled. However, no study has been performed to determine whether MPA actually develops an addiction-like behavior similar to those arising from other psychomotor stimulants. Thus, we attempted to determine whether MPA produces locomotor sensitization in a manner similar to amphetamine. In the first experiment, rats were pre-exposed to either saline or one of three different doses of MPA (0.2, 1.0, or 5.0mg/kg, IP) with a total of four injections, respectively. After a 2-week withdrawal period, when they were challenged with the same dose of MPA, only the group that was pre-exposed to high dose of MPA (5.0mg/kg) showed sensitized locomotor activity. In the second experiment, all rats were pre-exposed to MPA (5.0mg/kg) only. Interestingly, the expression of MPA-induced locomotor sensitization was inhibited by a pre-injection of a dopamine D2 receptor antagonist, eticlopride (0.05mg/kg, IP), though not by a dopamine D1 receptor antagonist, SCH23390 (0.01mg/kg, IP). These results suggest that repeated injection of MPA in the rat provokes certain neuronal changes involving specific, likely D2, dopamine receptor-mediated pathways that contribute to the expression of MPA-induced locomotor sensitization.


Subject(s)
Central Nervous System Stimulants/pharmacology , Dopamine Agents/pharmacology , Methamphetamine/analogs & derivatives , Motor Activity/drug effects , Receptors, Dopamine D1/metabolism , Receptors, Dopamine D2/metabolism , Thiophenes/pharmacology , Animals , Benzazepines/pharmacology , Dose-Response Relationship, Drug , Male , Methamphetamine/pharmacology , Motor Activity/physiology , Rats, Sprague-Dawley , Salicylamides/pharmacology
16.
Bioorg Med Chem ; 24(12): 2843-51, 2016 06 15.
Article in English | MEDLINE | ID: mdl-27157007

ABSTRACT

Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor which is strongly associated with tumor survival, progression, and therapeutic resistance. Accordingly, it has been suggested that the inhibition of the HIF-1 pathway can suppress tumor, and it has become an important therapeutic target. In present study, oltipraz, its metabolite M2, and their derivatives were synthesized and evaluated as HIF-1α inhibitors. Among the synthesized, benzyl-substituted pyrrolo[1,2-a]pyrazine 2g most potently inhibited HIF-1α protein accumulation (81% at 10µM) and VEGF, GLUT-1 transcription (77% and 92% at 10µM, respectively).


Subject(s)
Hypoxia-Inducible Factor 1, alpha Subunit/antagonists & inhibitors , Pyrazines/chemistry , Pyrazines/pharmacology , Thiones/chemistry , Thiones/pharmacology , Thiophenes/chemistry , Thiophenes/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Glucose Transporter Type 1/genetics , HCT116 Cells , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Insulin/metabolism , Pyrazines/chemical synthesis , Thiones/chemical synthesis , Thiophenes/chemical synthesis , Transcriptional Activation/drug effects , Vascular Endothelial Growth Factor A/genetics
17.
J Biol Chem ; 291(5): 2319-30, 2016 Jan 29.
Article in English | MEDLINE | ID: mdl-26627827

ABSTRACT

Epiregulin (EPR) is a ligand of the epidermal growth factor (EGF) family that upon binding to its epidermal growth factor receptor (EGFR) stimulates proliferative signaling, especially in colon cancer cells. Here, we describe the three-dimensional structure of the EPR antibody (the 9E5(Fab) fragment) in the presence and absence of EPR. Among the six complementarity-determining regions (CDRs), CDR1-3 in the light chain and CDR2 in the heavy chain predominantly recognize EPR. In particular, CDR3 in the heavy chain dramatically moves with cis-trans isomerization of Pro(103). A molecular dynamics simulation and mutational analyses revealed that Arg(40) in EPR is a key residue for the specific binding of 9E5 IgG. From isothermal titration calorimetry analysis, the dissociation constant was determined to be 6.5 nm. Surface plasmon resonance analysis revealed that the dissociation rate of 9E5 IgG is extremely slow. The superimposed structure of 9E5(Fab)·EPR on the known complex structure of EGF·EGFR showed that the 9E5(Fab) paratope overlaps with Domains I and III on the EGFR, which reveals that the 9E5(Fab)·EPR complex could not bind to the EGFR. The 9E5 antibody will also be useful in medicine as a neutralizing antibody specific for colon cancer.


Subject(s)
Antibodies, Monoclonal, Humanized/chemistry , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Epiregulin/chemistry , Animals , Antibodies, Monoclonal, Humanized/immunology , Calorimetry , DNA Mutational Analysis , Electron Spin Resonance Spectroscopy , Humans , Immunoglobulin G/chemistry , Mice , Molecular Dynamics Simulation , Mutagenesis, Site-Directed , Mutation , Protein Binding , Protein Structure, Tertiary , Recombinant Proteins/chemistry , Surface Plasmon Resonance
18.
Bioorg Med Chem ; 23(15): 4970-4979, 2015 Aug 01.
Article in English | MEDLINE | ID: mdl-26068017

ABSTRACT

Reactive oxygen species have been implicated in several diseases, particularly in ischemia-reperfusion injury. Quercetin 3-O-methyl ether has been reported to show potent antioxidant and neuroprotective activity against neuronal damage induced by reactive oxygen species. Several aminoethyl-substituted derivatives of quercetin 3-O-methyl ether have been synthesized to increase water solubility while retaining antioxidant and neuroprotective activity. Among such derivatives, compound 3a shows potent and well-balanced antioxidant activity in three types of cell-free assay systems and has in vivo neuroprotective effects on transient focal ischemic injury induced by the occlusion of the middle cerebral artery in rats.


Subject(s)
Antioxidants/chemical synthesis , Neuroprotective Agents/chemical synthesis , Quercetin/analogs & derivatives , Animals , Antioxidants/pharmacology , Antioxidants/therapeutic use , Brain/metabolism , Brain/pathology , Disease Models, Animal , Infarction, Middle Cerebral Artery/drug therapy , Lipid Peroxidation/drug effects , Male , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Quercetin/chemistry , Quercetin/pharmacology , Quercetin/therapeutic use , Rats , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Structure-Activity Relationship
19.
Bioorg Med Chem ; 23(1): 231-40, 2015 Jan 01.
Article in English | MEDLINE | ID: mdl-25468034

ABSTRACT

Alzheimer's disease (AD), a progressive and neurodegenerative disorder of the brain, is the most common cause of dementia among elderly people. To date, the successful therapeutic strategy to treat AD is maintaining the levels of acetylcholine by inhibiting acetylcholinesterase (AChE). In the present study, aurone derivatives were designed and synthesized as AChE inhibitors based on the lead structure of sulfuretin. Of those synthesized, compound 10d showed ca. 1700-fold and 6-fold higher AChE inhibitory activity than sulfuretin and galantamine, respectively. This compound also ameliorated scopolamine-induced memory deficit in mice when administered orally at the dose of 1 and 2mg/kg.


Subject(s)
Benzofurans/chemical synthesis , Cholinesterase Inhibitors/chemical synthesis , Alzheimer Disease/drug therapy , Animals , Benzofurans/chemistry , Benzofurans/pharmacology , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/pharmacology , Male , Mice
20.
Mol Cells ; 38(2): 151-5, 2015.
Article in English | MEDLINE | ID: mdl-25518925

ABSTRACT

Matrix metalloproteinase (MMP)-9 degrades type IV collagen in the basement membrane and plays crucial roles in several pathological implications, including tumorigenesis and inflammation. In this study, we analyzed the effect of flavonols on MMP-9 expression in phorbol-12-myristate-13-acetate (PMA)-induced human fibrosarcoma HT-1080 cells. Galangin and kaempferol efficiently decreased MMP-9 secretion, whereas fisetin only weakly decreased its secretion. Galangin and kaempferol did not affect cell viability at concentrations up to 30 µM. Luciferase reporter assays showed that galangin and kaempferol decrease transcription of MMP-9 mRNA. Moreover, galangin and kaempferol strongly reduce IκBα phosphorylation and significantly decrease JNK phosphorylation. These results indicate that galangin and kaempferol suppress PMA-induced MMP-9 expression by blocking activation of NF-κB and AP-1. Therefore, these flavonols could be used as chemopreventive agents to lower the risk of diseases involving MMP-9.


Subject(s)
Fibrosarcoma/genetics , Flavonoids/pharmacology , Kaempferols/pharmacology , Matrix Metalloproteinase 9/genetics , Tetradecanoylphorbol Acetate/analogs & derivatives , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Fibrosarcoma/chemically induced , Fibrosarcoma/metabolism , Gene Expression Regulation, Neoplastic , Humans , I-kappa B Proteins/metabolism , Matrix Metalloproteinase 9/metabolism , NF-KappaB Inhibitor alpha , Phosphorylation , Signal Transduction/drug effects , Tetradecanoylphorbol Acetate/toxicity
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