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1.
Life Sci ; 235: 116837, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31493481

RESUMO

AIMS: This study aimed to evaluate the effects of the sigma-1 receptor (S1R) on atrial fibrillation (AF) susceptibility in rats. MAIN METHODS: Rats were randomly assigned into three groups for intraperitoneal treatment with saline (CTL group), BD1047 (an antagonist of the S1R, BD group) or BD1047 plus fluvoxamine (an agonist of the S1R, BD + F group) for 4 weeks. The heart rate variability (HRV) and atrial electrophysiological parameters were measured via the PowerLab system and analyzed by LabChart 8.0 software. Atrial histology was determined with Masson staining. The protein levels of connexin (Cx) 40, Cav1.2, S1R, eNOS, p-eNOS, and p-AKT were detected by western blot assays. KEY FINDINGS: Our results showed that BD1047 significantly shortened the atrial effective refractory period (ERP) and action potential duration (APD), increased AF inducibility and duration, augmented sympathetic activity, depressed parasympathetic activity, and reduced heart rate variability (HRV) compared with the CTL group. Masson staining also showed a significant increase in atrial fibrosis in the BD group. Furthermore, the expressions of S1R, Cx40, Cav1.2, p-eNOS, and p-AKT were dramatically reduced in the BD group compared with the CTL group (all P < 0.01). However, fluvoxamine administration mitigated most of the abovementioned alterations. SIGNIFICANCE: Our findings indicated that S1R inhibition contributed to atrial electrical remodeling, cardiac autonomic remodeling and atrial fibrosis, which could be attenuated by fluvoxamine, thus providing new insights into the relationship between the S1R and AF.


Assuntos
Fibrilação Atrial/fisiopatologia , Remodelamento Atrial/fisiologia , Receptores sigma/antagonistas & inibidores , Receptores sigma/fisiologia , Potenciais de Ação , Animais , Fibrilação Atrial/patologia , Canais de Cálcio Tipo L , Conexinas/metabolismo , Etilenodiaminas/farmacologia , Fluvoxamina/farmacologia , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Frequência Cardíaca/efeitos dos fármacos , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Proteína Oncogênica v-akt/metabolismo , Ratos , Receptores sigma/agonistas , Receptores sigma/metabolismo
2.
Nucleic Acids Res ; 47(10): 5038-5048, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-30916320

RESUMO

PRMT5 is an arginine methyltransferase that accounts for the vast majority of the symmetric methylation in cells. PRMT5 exerts its function when complexed with MEP50/WDR77. This activity is often elevated in cancer cells and correlates with poor prognosis, making PRMT5 a therapeutic target. To investigate the PRMT5 signaling pathway and to identify genes whose loss-of-function sensitizes cancer cells to PRMT5 inhibition, we performed a CRISPR/Cas9 genetic screen in the presence of a PRMT5 inhibitor. We identified known components of the PRMT5 writer/reader pathway including PRMT5 itself, MEP50/WDR77, PPP4C, SMNDC1 and SRSF3. Interestingly, loss of PRMT1, the major asymmetric arginine methyltransferase, also sensitizes cells to PRMT5 inhibition. We investigated the interplay between PRMT5 and PRMT1, and found that combinatorial inhibitor treatment of small cell lung cancer and pancreatic cancer cell models have a synergistic effect. Furthermore, MTAP-deleted cells, which harbor an attenuated PRMT5-MEP50 signaling pathway, are generally more sensitive to PRMT1 inhibition. Together, these findings demonstrate that there is a degree of redundancy between the PRMT5 and PRMT1 pathways, even though these two enzymes deposit different types of arginine methylation marks. Targeting this redundancy provides a vulnerability for tumors carrying a co-deletion of MTAP and the adjacent CDKN2A tumor suppressor gene.


Assuntos
Deleção de Genes , Neoplasias/enzimologia , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo , Células A549 , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Etilenodiaminas/farmacologia , Humanos , Isoquinolinas/farmacologia , Células MCF-7 , Camundongos Knockout , Neoplasias/genética , Neoplasias/patologia , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Proteína-Arginina N-Metiltransferases/genética , Pirimidinas/farmacologia , Pirróis/farmacologia , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
3.
Am J Physiol Renal Physiol ; 316(4): F646-F653, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30649891

RESUMO

Zn2+ deficiency (ZnD) is a common comorbidity of many chronic diseases. In these settings, ZnD exacerbates hypertension. Whether ZnD alone is sufficient to alter blood pressure (BP) is unknown. To explore the role of Zn2+ in BP regulation, adult mice were fed a Zn2+-adequate (ZnA) or a Zn2+-deficient (ZnD) diet. A subset of ZnD mice were either returned to the ZnA diet or treated with hydrochlorothiazide (HCTZ), a Na+-Cl- cotransporter (NCC) inhibitor. To reduce intracellular Zn2+ in vitro, mouse distal convoluted tubule cells were cultured in N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN, a Zn2+ chelator)- or vehicle (DMSO)-containing medium. To replete intracellular Zn2+, TPEN-exposed cells were then cultured in Zn2+-supplemented medium. ZnD promoted a biphasic BP response, characterized by episodes of high BP. BP increases were accompanied by reduced renal Na+ excretion and NCC upregulation. These effects were reversed in Zn2+-replete mice. Likewise, HCTZ stimulated natriuresis and reversed BP increases. In vitro, Zn2+ depletion increased NCC expression. Furthermore, TPEN promoted NCC surface localization and Na+ uptake activity. Zn2+ repletion reversed TPEN effects on NCC. These data indicate that 1) Zn2+ contributes to BP regulation via modulation of renal Na+ transport, 2) renal NCC mediates ZnD-induced hypertension, and 3) NCC is a Zn2+-regulated transporter that is upregulated with ZnD. This study links dysregulated renal Na+ handling to ZnD-induced hypertension. Furthermore, NCC is identified as a novel mechanism by which Zn2+ regulates BP. Understanding the mechanisms of ZnD-induced BP dysregulation may have an important therapeutic impact on hypertension.


Assuntos
Hipertensão/metabolismo , Rim/metabolismo , Sódio/metabolismo , Zinco/deficiência , Animais , Pressão Sanguínea/efeitos dos fármacos , Células Cultivadas , Quelantes/farmacologia , Dieta , Etilenodiaminas/farmacologia , Hidroclorotiazida/farmacologia , Hipertensão/etiologia , Túbulos Renais Distais/efeitos dos fármacos , Túbulos Renais Distais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Natriurese/efeitos dos fármacos , Inibidores de Simportadores de Cloreto de Sódio/farmacologia
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 206: 421-429, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30172238

RESUMO

The coumarin-orthoaminophenol derivative was prepared under mild conditions. Based on crystallographic structure, IR and Raman, 1H and 13C NMR spectra the most applicable theoretical method was determined to be B3LYP-D3BJ. The stability and reactivity parameters were calculated, in the framework of NBO, QTAIM and Fukui functions, form the optimized structure. This reactivity was then probed in biological systems. The antimicrobial activity towards four bacteria and three fungi species was examined and activity was proven. In vitro cytotoxic effects, against human epithelial colorectal carcinoma HCT-116 and human healthy lung MRC-5 cell lines, of the investigated substance are also tested. Compound showed significant cytotoxic effects on HCT-116 cells, while on MRC-5 cells showed no cytotoxic effects. The effect of hydroxy group in ortho-position on the overall reactivity of molecule was examined through molecular docking with Glutathione-S-transferases.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Cumarínicos/química , Etilenodiaminas/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cumarínicos/farmacologia , Etilenodiaminas/farmacologia , Células HCT116 , Humanos , Espectroscopia de Ressonância Magnética , Viabilidade Microbiana/efeitos dos fármacos , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Drug Chem Toxicol ; 42(4): 430-435, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30203682

RESUMO

Biphenyl is found both in natural and anthropogenic sources and is used as a fungistat in the packaging of citrus fruits. Acute exposure to high levels of biphenyl has been observed to cause skin irritation and toxic effects on the liver and kidneys. However, the mechanisms of cytotoxicity induced by biphenyl are not yet well understood. In the present study, the cytotoxicity of biphenyl was studied by flow cytometry with fluorescent probes. Biphenyl at 100 µM significantly increased cell lethality after 3 h in rat thymocytes. In addition, biphenyl at 100 µM or more elevated intracellular Zn2+ levels. N,N,N',N'-Tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), an intracellular and extracellular Zn2+ chelator, but not diethylenetriamine-N,N,N',N″,N″-pentaacetic acid (DTPA), a membrane-impermeable Zn2+ chelator, attenuated the biphenyl-induced increase in intracellular Zn2+ levels and cell death. These results suggested that biphenyl-induced cytotoxicity caused an increase in intracellular Zn2+ levels, which was dependent on internal Zn2+. Moreover, biphenyl led to an increase in sensitivity to oxidative stress, while TPEN inhibited this biphenyl-induced increase. Our findings revealed that biphenyl caused an increase in the intracellular free Zn2+ concentration, inducing cytotoxicity, cell death, and an increase in sensitivity to oxidative stress.


Assuntos
Compostos de Bifenilo/toxicidade , Fungicidas Industriais/toxicidade , Timócitos/efeitos dos fármacos , Zinco/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Etilenodiaminas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Timócitos/metabolismo
6.
Stroke ; 49(9): 2200-2210, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30354980

RESUMO

Background and Purpose- Although intracellular zinc accumulation has been shown to contribute to neuronal death after cerebral ischemia, the mechanism by which zinc keeps on accumulating to cause severe brain damage remains unclear. Herein the dynamic cause-effect relationships between zinc accumulation and reactive oxygen species (ROS) production during cerebral ischemia/reperfusion are investigated. Methods- Rats were treated with zinc chelator, ROS scavenger, mitochondria-targeted ROS inhibitor, or NADPH oxidase inhibitor during a 90-minute middle cerebral artery occlusion. Cytosolic labile zinc, ROS level, cerebral infarct volume, and neurological functions were assessed after ischemia/reperfusion. Results- Zinc and ROS were colocalized in neurons, leading to neuronal apoptotic death. Chelating zinc reduced ROS production at 6 and 24 hours after reperfusion, whereas eliminating ROS reduced zinc accumulation only at 24 hours. Furthermore, suppression of mitochondrial ROS production reduced the total ROS level and brain damage at 6 hours after reperfusion but did not change zinc accumulation, indicating that ROS is produced mainly from mitochondria during early reperfusion and the initial zinc release is upstream of ROS generation after ischemia. Suppression of NADPH oxidase decreased ROS generation, zinc accumulation, and brain damage only at 24 hours after reperfusion, indicating that the majority of ROS is produced by NADPH oxidase at later reperfusion time. Conclusions- This study provides the direct evidence that there exists a positive feedback loop between zinc accumulation and NADPH oxidase-induced ROS production, which greatly amplifies the damaging effects of both. These findings reveal that different ROS-generating source contributes to ischemia-generated ROS at different time, underscoring the critical importance of spatial and temporal factors in the interaction between ROS and zinc accumulation, and the consequent brain injury, after cerebral ischemia/reperfusion.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Quelantes/farmacologia , Infarto da Artéria Cerebral Média/metabolismo , Neurônios/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Zinco/metabolismo , Animais , Compostos de Bifenilo/farmacologia , Encéfalo/metabolismo , Isquemia Encefálica/metabolismo , Etilenodiaminas/farmacologia , NADPH Oxidases/antagonistas & inibidores , Neurônios/metabolismo , Oniocompostos/farmacologia , Compostos Organometálicos/farmacologia , Pramipexol/farmacologia , Ratos , Salicilatos/farmacologia
7.
Molecules ; 23(10)2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297604

RESUMO

Two easily accessible, natural occurring triterpenoids, betulinic and ursolic acid, were used as starting materials for the synthesis of novel cytotoxic agents. A set of 28 ethylenediamine-spacered carboxamides was prepared holding an additional substituent connected to the ethylenediamine group. The compounds were screened in SRB assays to evaluate their cytotoxic activity employing several human tumor cell lines. Betulinic acid-derived carboxamides 17⁻30 showed significantly higher cytotoxicity than their ursolic acid analogs 3⁻16. In particular, compounds 25 and 26 were highly cytotoxic, as indicated by EC50 values lower than 1 µM.


Assuntos
Proliferação de Células/efeitos dos fármacos , Citotoxinas/química , Etilenodiaminas/química , Relação Estrutura-Atividade , Citotoxinas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Etilenodiaminas/farmacologia , Células HT29 , Humanos , Estrutura Molecular , Triterpenos/química
8.
ACS Appl Mater Interfaces ; 10(40): 33803-33813, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30221925

RESUMO

Synthetic anion transporters have been recognized as one of the potential therapeutic agents for the treatment of diseases including cystic fibrosis, myotonia, and epilepsy that originate due to the malfunctioning of natural Cl- ion transport systems. Recent studies showed that the synthetic Cl- ion transporters can also disrupt cellular ion-homeostasis and induce apoptosis in cancer cell lines, leading to a revived attention for synthetic Cl- ion transporters. Herein, we report the development of conformationally controlled 1,2-diphenylethylenediamine-based bis(thiourea) derivatives as a new class of selective Cl- ion carrier. The strong Cl- ion binding properties ( Kd = 3.87-6.66 mM) of the bis(thiourea) derivatives of diamine-based compounds correlate well with their transmembrane anion transport activities (EC50 = 2.09-4.15 nM). The transport of Cl- ions via Cl-/NO3- antiport mechanism was confirmed for the most active molecule. Perturbation of Cl- ion homeostasis by this anion carrier induces cell death by promoting the caspase-mediated intrinsic pathway of apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Canais de Cloreto/metabolismo , Etilenodiaminas , Ionóforos , Etilenodiaminas/síntese química , Etilenodiaminas/química , Etilenodiaminas/farmacologia , Células HeLa , Humanos , Transporte de Íons/efeitos dos fármacos , Ionóforos/síntese química , Ionóforos/química , Ionóforos/farmacologia
9.
J Biol Chem ; 293(38): 14669-14677, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30082314

RESUMO

Hypoxia-inducible factor 1α (HIF-1α) is a transcription factor that regulates cellular responses to hypoxia. It controls the expression of both BCL2/adenovirus E1B 19-kDa protein-interacting protein 3 (BNIP3) and insulin-like growth factor 2 (IGF2). Previous studies have demonstrated that in hypoxia, copper is required for the expression of BNIP3 but not for that of IGF2 Here, using ChIP assays, computational analyses, luciferase reporter assays, and real-time quantitative RT-PCR, we sought to better understand how copper regulates the differential target gene selectivity of HIF-1α. Human umbilical vein endothelial cells (HUVECs) were exposed to CoCl2 or hypoxia conditions to increase HIF-1α accumulation. The binding of HIF-1α to hypoxia-responsive element (HRE) sites in the BNIP3 or IGF2 gene promoter in high- or low-copper conditions was examined. Our analyses revealed three and two potential HRE sites in the BNIP3 and IGF2 promoters, respectively. We identified that HRE (-412/-404) in the BNIP3 promoter and HRE (-354/-347) in the IGF2 promoter are the critical binding sites of HIF-1α. Tetraethelenepentamine (TEPA)-mediated reduction in copper concentration did not affect hypoxia- or CoCl2-induced HIF-1α accumulation. However, the copper reduction did suppress the binding of HIF-1α to the HRE (-412/-404) in BNIP3 but not the binding of HIF-1α to the HRE (-354/-347) in IGF2 In summary, our findings uncovered the mechanistic basis for differential HIF-1α-mediated regulation of BNIP3 and IGF2, indicating that copper regulates target gene selectivity of HIF-1α at least in part by affecting HIF-1α binding to its cognate HRE in the promoters of these two genes.


Assuntos
Hipóxia Celular/genética , Cobre/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fator de Crescimento Insulin-Like II/genética , Proteínas de Membrana/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/genética , Imunoprecipitação da Cromatina , Cobalto/farmacologia , Etilenodiaminas/farmacologia , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Oxigênio/metabolismo , Ligação Proteica
10.
Ann Clin Lab Sci ; 48(4): 446-452, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30143485

RESUMO

OBJECTIVES: Previous studies have demonstrated that the inhibition of autophagy could reduce traumatic brain injury (TBI)-induced cell injury and attenuate behavioural outcomes. Meanwhile, synaptically released zinc translocation is found in the hippocampus of rats, and excessive release of chelatable zinc from excitatory synaptic vesicles is involved in the pathophysiological processes of TBI. We speculated that the release of zinc is closely connected with autophagy and that treatment with the zinc chelator N,N,N',N'-tetrakis-(2-pyridylmethyl) ethylenediamine (TPEN) could attenuate autophagy and thus improve histologic outcomes after TBI in rats. METHODS: Rats were randomly divided into three groups: sham group, CCI+vehicle group and CCI+TPEN group. TPEN (20 mg/kg/12 h, i.p) or vehicle (DMSO) was injected into the rats immediately after TBI, then given twice a day until the animals were sacrificed. Morphological changes associated with autophagy were tested by TEM. Zinc autometallography staining was used to evaluate chelatable zinc accumulation. Western blot analysis was used to detect protein expression. RESULTS: In our study, we found that treatment with TPEN reduced zinc translocation, reduced excitotoxicity and also partially reduced levels of LC3-II, Beclin1 and the ratio of Beclin-1/Bcl-2 in injured hippocampal neurons of rats, partially improving histologic outcomes after TBI. CONCLUSION: These data show that the zinc chelator TPEN plays a protective role in TBI, suggesting the possible involvement of autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/patologia , Etilenodiaminas/uso terapêutico , Neurônios/patologia , Sinapses/patologia , Zinco/uso terapêutico , Animais , Proteína Beclina-1/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Quelantes/farmacologia , Quelantes/uso terapêutico , Doença Crônica , Constrição Patológica , Etilenodiaminas/farmacologia , Hipocampo/patologia , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/ultraestrutura , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Sinapses/ultraestrutura , Resultado do Tratamento
11.
Colloids Surf B Biointerfaces ; 170: 463-469, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29960214

RESUMO

Selenium (Se) incorporated into organic frameworks has demonstrated anticancer activity against several cancer types. One of the drawbacks of most of these constructs is their poor solubility and bioavailability, which can be overcome with the use of suitable nanocarriers. We have synthesized a series of 5-substituted amide selenodiazoles, based on the parent structure of ebselen, an organoselenium drug with proven cytoprotective activity, and solubilized them in polymeric micelles of poloxamines, poly(ethylene oxide)-poly(propylene oxide) X-shaped tetrablock-copolymers. Scattering methods (SANS and DLS) were employed to characterize the micellar nanocarriers. MTT biological evaluation highlights the selectivity of the Se-compounds towards cancer cells, with MCF-7 standing as the most responsive line. The alkylation of the heterocycle with a 12-carbon hydrophobic tail displays the highest activity, showing a 100-fold increase with respect to ebselen. This compound also exhibits the greatest increase in solubility in poloxamine micelles, overall resulting in a one-fold increase in activity with respect to the non-formulated form, making it a hit compound for further optimization.


Assuntos
Antineoplásicos/farmacologia , Azóis/farmacologia , Etilenodiaminas/farmacologia , Micelas , Compostos de Selênio/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Azóis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Etilenodiaminas/química , Humanos , Estrutura Molecular , Tamanho da Partícula , Compostos de Selênio/síntese química , Compostos de Selênio/química , Relação Estrutura-Atividade , Propriedades de Superfície
12.
FEBS J ; 285(16): 3077-3096, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29943906

RESUMO

Malaria is a deadly disease killing worldwide hundreds of thousands people each year and the responsible parasite has acquired resistance to the available drug combinations. The four vacuolar plasmepsins (PMs) in Plasmodium falciparum involved in hemoglobin (Hb) catabolism represent promising targets to combat drug resistance. High antimalarial activities can be achieved by developing a single drug that would simultaneously target all the vacuolar PMs. We have demonstrated for the first time the use of soluble recombinant plasmepsin II (PMII) for structure-guided drug discovery with KNI inhibitors. Compounds used in this study (KNI-10742, 10743, 10395, 10333, and 10343) exhibit nanomolar inhibition against PMII and are also effective in blocking the activities of PMI and PMIV with the low nanomolar Ki values. The high-resolution crystal structures of PMII-KNI inhibitor complexes reveal interesting features modulating their differential potency. Important individual characteristics of the inhibitors and their importance for potency have been established. The alkylamino analog, KNI-10743, shows intrinsic flexibility at the P2 position that potentiates its interactions with Asp132, Leu133, and Ser134. The phenylacetyl tripeptides, KNI-10333 and KNI-10343, accommodate different ρ-substituents at the P3 phenylacetyl ring that determine the orientation of the ring, thus creating novel hydrogen-bonding contacts. KNI-10743 and KNI-10333 possess significant antimalarial activity, block Hb degradation inside the food vacuole, and show no cytotoxicity on human cells; thus, they can be considered as promising candidates for further optimization. Based on our structural data, novel KNI derivatives with improved antimalarial activity could be designed for potential clinical use. DATABASE: Structural data are available in the PDB under the accession numbers 5YIE, 5YIB, 5YID, 5YIC, and 5YIA.


Assuntos
Ácido Aspártico Endopeptidases/antagonistas & inibidores , Ácido Aspártico Endopeptidases/metabolismo , Etilenodiaminas/química , Isoquinolinas/química , Peptidomiméticos/farmacologia , Tiazóis/química , Antimaláricos/química , Antimaláricos/farmacologia , Ácido Aspártico Endopeptidases/química , Ácido Aspártico Endopeptidases/genética , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos/métodos , Etilenodiaminas/farmacologia , Hemoglobinas/metabolismo , Humanos , Isoquinolinas/farmacologia , Terapia de Alvo Molecular/métodos , Peptidomiméticos/química , Plasmodium falciparum/efeitos dos fármacos , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Conformação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Tiazóis/farmacologia
13.
Int J Biochem Cell Biol ; 101: 54-63, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29800726

RESUMO

Sodium fluorescein ('fluorescein') staining of the ocular surface is frequently an indicator of compromised ocular health, and increases in the presence of certain contact lens multi-purpose solutions (MPS), a phenomenon known as solution induced corneal staining (SICS). The mechanism(s) underpinning fluorescein hyperfluorescence are uncertain, though may reflect increased cellular uptake of fluorescein by corneal epithelial cells. We have developed an in vitro model to study fluorescein uptake in both 'generic' mammalian cells (murine fibroblasts) and human corneal cells. Fluorescein hyperfluorescence increased after treatment with two MPS associated with clinical corneal fluorescein staining, yet there was no cellular hyperfluorescence for two MPS that do not cause this staining. Increased fluorescein uptake did not correlate with presence of a necrotic or an apoptotic marker (propidium iodide and caspase-3 respectively). Incubation of MPS-treated cells with dynasore (an inhibitor of dynamin, implicated in endocytic pathways) reduced fluorescein uptake irrespective of MPS treatment. The non-ionic surfactant Tetronic 1107 (present in both MPS associated with corneal fluorescein staining) increased uptake of fluorescein for both cell types, whereas an unrelated surfactant (Triton X-100) did not. We conclude that the clinical hyperfluorescence profile observed after exposure to four MPS can be reproduced using a simple model of cellular fluorescein uptake, suggesting this is the biological basis for SICS. Fluorescein entry does not correlate with necrosis or apoptosis, but instead involves a dynamin-dependent active process. Moreover the surfactant Tetronic 1107 appears to be a key MPS constituent triggering increased fluorescein entry, and may be the major factor responsible for SICS.


Assuntos
Soluções para Lentes de Contato/farmacologia , Dinaminas/antagonistas & inibidores , Endocitose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Etilenodiaminas/farmacologia , Animais , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular , Soluções para Lentes de Contato/química , Córnea/citologia , Córnea/efeitos dos fármacos , Córnea/metabolismo , Dinaminas/genética , Dinaminas/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fluoresceína/metabolismo , Fluorescência , Corantes Fluorescentes/metabolismo , Expressão Gênica , Humanos , Hidrazonas/farmacologia , Camundongos , Microscopia de Fluorescência , Propídio/química , Coloração e Rotulagem/métodos
14.
Dalton Trans ; 47(21): 7178-7189, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29651471

RESUMO

A series of neutral pseudo-octahedral RuII sulfonamidoethylenediamine complexes [(η6-p-cym)Ru(N,N')Cl] where N,N' is N-(2-(R1,R2-amino)ethyl)-4-toluenesulfonamide (TsEn(R1,R2)) R1,R2 = Me,H (1); Me,Me (2); Et,H (3); benzyl,H (Bz, 4); 4-fluorobenzyl,H (4-F-Bz, 5) or naphthalen-2-ylmethyl,H (Naph, 6), were synthesised and characterised including the X-ray crystal structure of 3. These complexes catalyse the reduction of NAD+ regioselectively to 1,4-NADH by using formate as the hydride source. The catalytic efficiency depends markedly on the steric and electronic effects of the N-substitutent, with turnover frequencies (TOFs) increasing in the order: 1 < 2 < 3, 6 < 4, 5, achieving a TOF of 7.7 h-1 for 4 with a 95% yield of 1,4-NADH. The reduction rate was highest between pH* (deuterated solvent) 6 and 7.5 and improved with an increase in formate concentration (TOF of 18.8 h-1, 140 mM formate). The calculations suggested initial substitution of an aqua ligand by formate, followed by hydride transfer to RuII and then to NAD+, and indicated specific interactions between the aqua complex and both NAD+ and NADH, the former allowing a preorganisation involving interaction between the aqua ligand, formate anion and the pyridine ring of NAD+. The complexes exhibited antiproliferative activity towards A2780 human ovarian cancer cells with IC50 values ranging from 1 to 31 µM, the most potent complex, [(η6-p-cym)Ru(TsEn(Bz,H))Cl] (4, IC50 = 1.0 ± 0.1 µM), having a potency similar to the anticancer drug cisplatin. Co-administration with sodium formate (2 mM), increased the potency of all complexes towards A2780 cells by 20-36%, with the greatest effect seen for complex 6.


Assuntos
Antineoplásicos/farmacologia , Coenzimas/metabolismo , Formiatos/metabolismo , NAD/metabolismo , Compostos Organometálicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Biocatálise , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Etilenodiaminas/química , Etilenodiaminas/farmacologia , Formiatos/química , Humanos , Concentração de Íons de Hidrogênio , Hidrogenação/efeitos dos fármacos , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Teoria Quântica , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Rutênio/química , Rutênio/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia
15.
J Mol Cell Cardiol ; 118: 169-182, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29605530

RESUMO

Serine 727 (Ser727) phosphorylation of STAT3 plays a role in the regulation of mitochondrial respiration. This study aimed to test if zinc could regulate mitochondrial respiration through phosphorylation of STAT3 at Ser727 in the setting of ischemia/reperfusion in the heart. Under normoxic conditions, treatment of isolated rat hearts with ZnCl2 increased cytosolic STAT3 phosphorylation at Ser727 followed by phospho-STAT3 translocation to mitochondria. In isolated rat hearts subjected to 30 min regional ischemia followed by 20 min of reperfusion, ZnCl2 given 5 min before the onset of reperfusion also increased mitochondrial phospho-STAT3. ZnCl2 enhanced ERK phosphorylation and PD98059 reversed the effect of ZnCl2 on STAT3 phosphorylation. ZnCl2 improved the mitochondrial oxidative phosphorylation at reperfusion. This effect was abolished by STAT3S727A, a mutant in which Ser727 is replaced with alanine, in H9c2 cells subjected to hypoxia/reoxygenation. In addition, ZnCl2 increased the mRNA level of the complex I subunit ND6, which was also reversed by STAT3S727A. Moreover, ZnCl2 attenuated mitochondrial ROS generation and dissipation of mitochondrial membrane potential (ΔΨm) at reoxygenation through Ser727 phosphorylation. Finally, ZnCl2 suppression of succinate dehydrogenase (SDH) activity upon the onset of reperfusion was nullified by the Ser727 mutation. In conclusion, zinc improves cardiac oxidative phosphorylation and inhibits mitochondrial ROS generation at reperfusion by increasing mitochondrial STAT3 phosphorylation at Ser727 via ERK. The preservation of ND6 mtDNA and the inhibition of SDH activity may account for the role of STAT3 in the beneficial action of zinc on the mitochondrial oxidative phosphorylation and ROS generation at reperfusion.


Assuntos
Mitocôndrias/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Fosfosserina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Zinco/farmacologia , Animais , Linhagem Celular , Respiração Celular/efeitos dos fármacos , Etilenodiaminas/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Masculino , Mitocôndrias/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/patologia , Fosforilação/efeitos dos fármacos , Ratos Wistar , Fator de Transcrição STAT3/metabolismo , Succinato Desidrogenase/metabolismo
16.
Anticancer Agents Med Chem ; 18(11): 1617-1628, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29697031

RESUMO

BACKGROUND: Breast cancer is the second most common cancer worldwide. N, N, N', N'-Tetrakis (2-pyridylmethyl)-ethylenediamine (TPEN) is a lipid-soluble zinc metal chelator that induces apoptosis in cancer cells through oxidative stress (OS). However, the effectiveness and the mechanisms involved in TPENinduced cell death in mammary adenocarcinoma cells in vitro and in vivo are still unclear. OBJECTIVE: This study aimed to evaluate the cytotoxic effect of TPEN in mouse embryonic fibroblasts (MEFs, as normal control cells) and mammary adenocarcinoma cancer cells (TS/A cells) in vitro and in a mammary tumor model in vivo. METHODS: Cells were treated with TPEN (0-3 µM), and changes in nuclear chromatin and DNA, mitochondrial membrane potential (ΔΨm), and intracellular reactive oxygen species (ROS) levels were determined by both fluorescence microscopy and flow cytometry. Cell proliferation and the cell cycle were also analyzed. Cellular markers of apoptosis were evaluated by Western blot. Finally, the effect of TPEN in a mammary adenocarcinoma tumor model in vivo was determined by immunohistological analyses. RESULTS: TPEN induced apoptosis in TS/A cells in a dose-dependent manner, increasing nuclear chromatin condensation, DNA fragmentation, cell cycle arrest and ΔΨm loss. Additionally, TPEN increased dichlorofluorescein fluorescence (DCF+) intensity, indicative of ROS production; increased DJ-1-Cys106-sulfonate expression, a marker of intracellular H2O2 stress; induced p53 and PUMA upregulation; and activated caspase-3. Moreover, TPEN induced mammary cancer cell elimination and tumor size reduction in vivo 48 h after treatment through an OS-induced apoptotic mechanism. CONCLUSION: TPEN selectively induces apoptosis in TS/A cells through an H2O2-mediated signaling pathway. Our findings support the use of TPEN as a potential treatment for breast cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Caspase 3/metabolismo , Etilenodiaminas/farmacologia , Peróxido de Hidrogênio/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Etilenodiaminas/química , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais/efeitos dos fármacos
17.
Biomacromolecules ; 19(4): 1091-1099, 2018 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-29528623

RESUMO

Synthetic hydrogel materials can recapitulate the natural cell microenvironment; however, it is equally necessary that the gels maintain cell viability and phenotype while permitting reisolation without stress, especially for use in the stem cell field. Here, we describe a family of synthetically accessible, squaramide-based tripodal supramolecular monomers consisting of a flexible tris(2-aminoethyl)amine (TREN) core that self-assemble into supramolecular polymers and eventually into self-recovering hydrogels. Spectroscopic measurements revealed that monomer aggregation is mainly driven by a combination of hydrogen bonding and hydrophobicity. The self-recovering hydrogels were used to encapsulate NIH 3T3 fibroblasts as well as human-induced pluripotent stem cells (hiPSCs) and their derivatives in 3D. The materials reported here proved cytocompatible for these cell types with maintenance of hiPSCs in their undifferentiated state essential for their subsequent expansion or differentiation into a given cell type and potential for facile release by dilution due to their supramolecular nature.


Assuntos
Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Polímeros/farmacologia , Quinina/análogos & derivados , Animais , Sobrevivência Celular/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Etilenodiaminas/química , Etilenodiaminas/farmacologia , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Camundongos , Células NIH 3T3 , Polímeros/síntese química , Quinina/síntese química , Quinina/farmacologia
18.
Chem Biodivers ; 15(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29032600

RESUMO

The synthesis, spectroscopic properties, and in vitro cytotoxicity activity of a series of various salen-based triboron complexes have been designed and prepared from hemi-salen (L1 H3  - L4 H3 ) ligands and BF3 ·Et2 O or BPh3 under simple reaction conditions. The hemi-salen (L1 H3  - L4 H3 ) ligands and their BF2 or BPh2 chelating triboron complexes were characterized by means of NMR (1 H, 13 C, 19 F, and 11 B) spectra, FT-IR spectra, UV/VIS spectra, fluorescence spectra, mass spectra, melting point, as well as elemental analysis. The triboron [L(1 - 4) (BF2 )3 ] and [L(1 - 4) (BPh2 )3 ] complexes were investigated for their absorption and emission properties, and these complexes are also good chelates towards boron(III) fragments such as BF2 or BPh2 quantum yield in solution reaching up to 38%. The hemi-salen (L1 H3  - L4 H3 ) ligands and their BF2 or BPh2 chelating triboron complexes were tested for the in vitro anticancer activity against various cancer and normal cells (HeLa, DLD-1, ECC-1, PC-3, PNT-1A, and CRL-4010), and it was found that the cell viability of cancer cells was decreased while most of the healthy cells could still be viable. Also, the cytotoxicity studies showed that anticancer activity of hemi-salen (L1 H3  - L4 H3 ) ligands is higher than that of triboron [L(1 - 4) (BF2 )3 ] and [L(1 - 4) (BPh2 )3 ] complexes. The hemi-salen (L1 H3  - L4 H3 ) ligands showing the strongest cytotoxic effect in PC-3 cells were found to exhibit anticancer activity with apoptosis by increasing the level of ROS in the PC-3 cells.


Assuntos
Antineoplásicos/farmacologia , Compostos de Boro/farmacologia , Etilenodiaminas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Compostos de Boro/síntese química , Compostos de Boro/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Etilenodiaminas/síntese química , Etilenodiaminas/química , Humanos , Ligantes , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
19.
Carbohydr Polym ; 180: 1-12, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29103484

RESUMO

This work aims to prepare 3,6-O-N-acetylethylenediamine modified chitosan (AEDMCS) and evaluate its potential use as an antimicrobial wound dressing material. UV, FTIR, and 1H NMR results demonstrated N-acetylethylenediamine groups were successfully grafted to C3OH and C6OH on polysaccharide skeletons. TGA, XRD, and solubility tests indicated that as compared with chitosan, AEDMCS had diminished thermostability, decreased crystallinity, and greatly improved solubility. AEDMCS, with degrees of deacetylation and substitution being respectively 90.3% and 0.72, exhibited higher antibacterial activity than chitosan against six bacteria generally causing wound infections. Meanwhile, AEDMCS had permissible hemolysis and cytotoxicity and low BSA adsorption even at a AEDMCS concentration of 25mg/mL. Acute toxicity tests showed AEDMCS was nontoxic. Moreover, the wound healing property was preliminarily evaluated, illustrating that AEDMCS enhanced wound healing rates as expected and had no significant differences as compared with chitosan. These results suggested AEDMCS might be a potential material used as antibacterial wound dressings.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Quitosana/análogos & derivados , Quitosana/farmacologia , Etilenodiaminas/farmacologia , Curativos Oclusivos , Adsorção , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/toxicidade , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Bovinos , Quitosana/síntese química , Quitosana/toxicidade , Etilenodiaminas/síntese química , Etilenodiaminas/química , Etilenodiaminas/toxicidade , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Masculino , Camundongos , Coelhos , Soroalbumina Bovina/química , Solubilidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Água/química , Cicatrização/efeitos dos fármacos
20.
Chem Biol Drug Des ; 91(3): 781-788, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29130625

RESUMO

The biological behavior of 68 Ga-based radiopharmaceuticals can be significantly affected by the chelators' attributes (size, charge, lipophilicity). Thus, this study aimed at examining the influence of three different chelators, DOTAGA, NODAGA, and HBED-CC on the distribution pattern of 68 Ga-labeled NGR peptides targeting CD13 receptors. 68 Ga-DOTAGA-c(NGR), 68 Ga-NODAGA-c(NGR), and 68 Ga-HBED-CC-c(NGR) were observed to be hydrophilic with respective log p values being -3.5 ± 0.2, -3.3 ± 0.08, and -2.8 ± 0.14. The three radiotracers exhibited nearly similar uptake in human fibrosarcoma HT-1080 tumor cells with 86%, 63%, and 33% reduction during blocking studies with unlabeled cNGR peptide for 68 Ga-DOTAGA-c(NGR), 68 Ga-NODAGA-c(NGR), and 68 Ga-HBED-CC-c(NGR), respectively, indicating higher receptor specificity of the first two radiotracers. The neutral radiotracer 68 Ga-NODAGA-c(NGR) demonstrated better target-to-non-target ratios during in vivo studies compared to its negatively charged counterparts, 68 Ga-DOTAGA-c(NGR) and 68 Ga-HBED-CC-c(NGR). The three radiotracers had similar HT-1080 tumor uptake and being hydrophilic exhibited renal excretion with minimal uptake in non-target organs. Significant reduction (p < .005) in HT-1080 tumor uptake of the radiotracers was observed during blocking studies. It may be inferred from these studies that the three radiotracers are promising probes for in vivo imaging of CD13 receptor expressing cancer sites; however, 68 Ga-NODAGA-c(NGR) is a better candidate.


Assuntos
Acetatos , Quelantes , Sistemas de Liberação de Medicamentos/métodos , Etilenodiaminas , Radioisótopos de Gálio , Compostos Heterocíclicos com 1 Anel , Imagem Molecular/métodos , Neoplasias , Oligopeptídeos , Compostos Radiofarmacêuticos , Acetatos/síntese química , Acetatos/química , Acetatos/farmacologia , Linhagem Celular Tumoral , Quelantes/síntese química , Quelantes/química , Quelantes/farmacologia , Etilenodiaminas/síntese química , Etilenodiaminas/química , Etilenodiaminas/farmacologia , Radioisótopos de Gálio/química , Radioisótopos de Gálio/farmacologia , Compostos Heterocíclicos com 1 Anel/síntese química , Compostos Heterocíclicos com 1 Anel/química , Compostos Heterocíclicos com 1 Anel/farmacologia , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Oligopeptídeos/síntese química , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacologia
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