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1.
Molecules ; 29(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38930989

RESUMO

The crystal structures of two newly synthesized nitrilotriacetate oxidovanadium(IV) salts, namely [QH][VO(nta)(H2O)](H2O)2 (I) and [(acr)H][VO(nta)(H2O)](H2O)2 (II), were determined. Additionally, the cytotoxic effects of four N-heterocyclic nitrilotriacetate oxidovanadium(IV) salts-1,10-phenanthrolinium, [(phen)H][VO(nta)(H2O)](H2O)0.5 (III), 2,2'-bipyridinium [(bpy)H][VO(nta)(H2O)](H2O) (IV), and two newly synthesized compounds (I) and (II)-were evaluated against prostate cancer (PC3) and breast cancer (MCF-7) cells. All the compounds exhibited strong cytotoxic effects on cancer cells and normal cells (HaCaT human keratinocytes). The structure-activity relationship analysis revealed that the number and arrangement of conjugated aromatic rings in the counterion had an impact on the antitumor effect. The compound (III), the 1,10-phenanthrolinium analogue, exhibited the greatest activity, whereas the acridinium salt (II), with a different arrangement of three conjugated aromatic rings, showed the lowest toxicity. The increased concentrations of the compounds resulted in alterations to the cell cycle distribution with different effects in MCF-7 and PC3 cells. In MCF-7 cells, compounds I and II were observed to block the G2/M phase, while compounds III and IV were found to arrest the cell cycle in the G0/G1 phase. In PC3 cells, all compounds increased the rates of cells in the G0/G1 phase.


Assuntos
Antineoplásicos , Neoplasias da Mama , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Masculino , Feminino , Células MCF-7 , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Ácido Nitrilotriacético/química , Ácido Nitrilotriacético/análogos & derivados , Relação Estrutura-Atividade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/síntese química , Vanádio/química , Vanádio/farmacologia , Células PC-3 , Ciclo Celular/efeitos dos fármacos , Estrutura Molecular , Sais/química , Sais/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos
2.
J Oleo Sci ; 71(10): 1481-1492, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36089399

RESUMO

Renal tissue plays a crucial function in maintaining homeostasis, making it vulnerable to xenobiotic toxicity. Pueraria montana has more beneficial potential against the various diseases and has long history used as a traditional Chinese medicine. But its effect against the renal cancer not scrutinize. The goal of this study is to see if Pueraria montana can protect rats from developing kidney tumors caused by diethylnitrosamine (DEN) and ferric nitrite (Fe-NTA). Wistar rats was selected for the current study and DEN (use as an inducer) and Fe-NTA (promoter) for induction the renal cancer. For 22 weeks, the rats were given orally Pueraria montana (12.5, 25, and 50 mg/kg) treatment. At regular intervals, the body weight and food intake were calculated. The rats were macroscopically evaluated for identification of cancer in the renal tissue. The renal tumor makers, renal parameters, antioxidant enzymes, phase I and II enzymes, inflammatory cytokines and mediators were estimated at end of the experimental study. Pueraria montana treated rats displayed the suppression of renal tumors, incidence of the tumors along with suppression of tumor percentage. Pueraria montana treated rats significantly (p < 0.001) increased body weight and suppressed the renal weight and food intake. It also reduced the level of renal tumor marker ornithine decarboxylase (ODC) and [3H] thymidine incorporation along with suppression of renal parameter such as uric acid, blood urea nitrogen (BUN), urea and creatinine. Pueraria montana treatment significantly (p < 0.001) altered the level of phase enzymes and antioxidant. Pueraria montana treatment significantly (p < 0.001) repressed the level of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and improved the level of interleukin-10 (IL-10). Pueraria montana treatment suppressed the level of prostaglandin (PGE2), cyclooxygenase-2 (COX-2), nuclear kappa B factor (NF-κB) and transforming growth factor beta 1 (TGF-ß1). Pueraria montana suppressed the inflammatory necrosis, size the bowman capsules in the renal histopathology. Pueraria montana exhibited the chemoprotective effect via dual mechanism such as suppression of inflammatory reaction and oxidative stress.


Assuntos
Neoplasias Renais , Pueraria , Animais , Antioxidantes/farmacologia , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/farmacologia , Peso Corporal , Creatinina/farmacologia , Ciclo-Oxigenase 2/metabolismo , Dietilnitrosamina/farmacologia , Compostos Férricos , Inflamação/tratamento farmacológico , Interleucina-10 , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/metabolismo , NF-kappa B/metabolismo , Ácido Nitrilotriacético/análogos & derivados , Nitritos/farmacologia , Ornitina Descarboxilase/metabolismo , Ornitina Descarboxilase/farmacologia , Estresse Oxidativo , Prostaglandinas , Prostaglandinas E/metabolismo , Prostaglandinas E/farmacologia , Pueraria/metabolismo , Ratos , Ratos Wistar , Timidina/metabolismo , Timidina/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Ureia , Ácido Úrico/farmacologia , Xenobióticos/farmacologia
3.
Cancer Sci ; 113(1): 65-78, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34699654

RESUMO

Cancer susceptibility is a critical factor in the understanding of carcinogenesis. Intraperitoneal (i.p.) injection of an iron chelate, ferric nitrilotriacetate (Fe-NTA), produces hydroxyl radicals via Fenton reaction to induce ferroptosis in renal proximal tubules. Rats or mice subjected to repeated i.p. injections of Fe-NTA develop renal cell carcinoma (RCC). To elucidate the molecular mechanisms that cause susceptibility to renal carcinogenesis, we first established an inter-strain difference in the susceptibility to Fe-NTA-induced renal carcinogenesis in mice. Based on a previous observation of a low incidence of RCC with this model in C57BL/6J strain mice, we investigated A/J strain mice here, which demonstrated significantly higher susceptibility to Fe-NTA-induced renal carcinogenesis. Homozygous deletion of the Cdkn2a/2b tumor suppressor locus was detected for the first time in A/J strain mice. Focusing on ferroptosis and iron metabolism, we explored the mechanisms involved that lead to the difference in RCC development. We compared the protective responses in the kidney of A/J and C57BL/6J strains after Fe-NTA treatment. After 3-week Fe-NTA treatment, A/J mice maintained higher levels of expression of glutathione peroxidase 4 and xCT (SLC7A11), leading to a lower level of lipid peroxidation. Simultaneously, A/J mice had decreased expression of transferrin receptor and increased expression of ferritin to greater degrees than C57BL/6 mice. After a single Fe-NTA injection, higher levels of oxidative cell damage and cytosolic catalytic Fe(II) were observed in C57BL/6J mice, accompanied by a greater increase in lipocalin-2. Lipocalin-2 deficiency significantly decreased oxidative renal damage. Our results suggest that a genetic trait favoring ferroptosis resistance contributes to high susceptibility to Fe-NTA-induced RCC in A/J strain.


Assuntos
Carcinoma de Células Renais/patologia , Compostos Férricos/efeitos adversos , Redes Reguladoras de Genes , Neoplasias Renais/patologia , Ácido Nitrilotriacético/análogos & derivados , Deleção de Sequência , Animais , Carcinoma de Células Renais/induzido quimicamente , Carcinoma de Células Renais/genética , Transportador 1 de Aminoácidos Catiônicos/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Ferritinas/genética , Ferroptose , Regulação Neoplásica da Expressão Gênica , Homozigoto , Injeções Intraperitoneais , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/genética , Peroxidação de Lipídeos , Lipocalina-2/genética , Masculino , Camundongos , Neoplasias Experimentais , Ácido Nitrilotriacético/efeitos adversos , Estresse Oxidativo , Receptores da Transferrina/genética , Especificidade da Espécie , Regulação para Cima
4.
Biomed Pharmacother ; 139: 111636, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33957566

RESUMO

This study was designed to reveal the protective effects of dietary supplementation of curcumin against renal cell tumours and oxidative stress induced by renal carcinogen iron nitrilotriacetate (Fe-NTA) in ddY male mice. The results showed that mice treated with a renal carcinogen, Fe-NTA, a 35% renal cell tumour incidence was noticed, whereas renal cell tumour occurrence was elevated to 80% in Fe-NTA promoted and N-diethylnitrosamine (DEN)-initiated mice as compared with saline- treated mice. No incidence of tumours has been observed in DEN-initiated non-promoted mice. Diet complemented with 0.5% and 1.0% curcumin fed prior to, during and after treatment with Fe-NTA in DEN-initiated animals, tumour incidence was reduced dose-dependently to about 45% and 30% respectively. Immunohistochemical studies also revealed the increased formation of 4-hydroxy-2-nonenal (HNE)-modified protein adducts and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in kidney tissue of mice treated with an intraperitoneal injection of Fe-NTA (6.0 mg Fe/kg body weight.). Furthermore, Fe-NTA treatment of mice also resulted in significant elevation of malondialdehyde (MDA), serum urea, and creatinine and decreases renal glutathione. However, the changes in most of these parameters were attenuated dose-dependently by prophylactic treatment of animals with 0.5% and 1% curcumin diet, this may be due to its antioxidative impact of curcumin. These results suggest that intake of curcumin is beneficial for the prevention of renal cell tumours and oxidative stress damage mediated by renal carcinogen, Fe-NTA.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Antioxidantes/uso terapêutico , Carcinoma de Células Renais/induzido quimicamente , Carcinoma de Células Renais/tratamento farmacológico , Curcumina/uso terapêutico , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina , Aldeídos , Animais , Anticarcinógenos/farmacologia , Nitrogênio da Ureia Sanguínea , Carcinógenos , Creatinina/sangue , Dieta , Dietilnitrosamina , Relação Dose-Resposta a Droga , Compostos Férricos , Masculino , Camundongos , Ácido Nitrilotriacético/análogos & derivados
5.
Langmuir ; 35(6): 2047-2054, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30605338

RESUMO

Herein, we report the self-assembly of a synthetic vanilloid receptor (VR) peptide that selectively binds capsaicin. We synthesized a 26-mer peptide-YSEILFFVQS-HHHHHH-LAMGWTNMLY (S3HS4)-comprising two chemoreceptor domains of transient receptor potential channel (TRPV1) linked by a hexahistidine sequence. High-speed atomic force microscopy (AFM) imaging in water revealed that the peptide structures alternated rapidly between wedge shape and linear forms. Circular dichroism spectroscopy showed that 65% of the amide units in the peptide chain adopted an α-helix structure, which was ascribed to the chemoreceptor domains. S3HS4 developed well-packed monolayers at the Ni-treated thiolated nitrilotriacetic acid self-assembled monolayers by chelation of the hexahistidine segment, as characterized by infrared spectroscopy and AFM, which exhibited statistically constant specific height. Therefore, S3HS4 was expected to fold spontaneously upon chelation, and the resulting helix-turn-helix conformers developed films while uniformly oriented: the tilt angle was 69° from the surface normal to the substrate. According to microgravimetric analysis using a quartz crystal microbalance (QCM), the adsorption was 84 ± 47 pmol cm-2 ( n = 3), which was almost consistent with the saturation adsorption of an α-helix unit. We also used a QCM to investigate the host-guest reactions of S3HS4 and found that the S3HS4-attached QCM-chip-bound capsaicin with an apparent binding constant of (4.2 ± 3.6) × 104 M-1 ( n = 4), whereas there was no evidence of binding to vanillin or acetophenone. Two controls-a blank chip without S3HS4 and a chip modified with a single helical peptide (LAMGWTNMLY-HHHHHH)-produced no capsaicin response. To the best of our knowledge, S3HS4 is the first example of a synthetic VR mimic peptide. We believe that the present surface-directed structure-based design can be used to exploit the α-helix bundle in hexahistidine-linked bishelical peptides.


Assuntos
Capsaicina/metabolismo , Ácido Nitrilotriacético/análogos & derivados , Compostos Organometálicos/química , Fragmentos de Peptídeos/metabolismo , Canais de Cátion TRPV/metabolismo , Sequência de Aminoácidos , Capsaicina/química , Dicroísmo Circular , Membranas Artificiais , Microscopia de Força Atômica , Ácido Nitrilotriacético/química , Fragmentos de Peptídeos/química , Ligação Proteica , Conformação Proteica em alfa-Hélice , Domínios Proteicos , Engenharia de Proteínas , Técnicas de Microbalança de Cristal de Quartzo , Canais de Cátion TRPV/química
6.
J Biotechnol ; 289: 88-92, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30496775

RESUMO

The phage display technique is a combinatorial technology in which random peptides are displayed on the surface of the phage; it is widely used to identify high-affinity peptides that bind to a target protein. However, this technique presents several problems due to non-specific binding of the phages and steric hindrance caused by blocking agents. To overcome these problems, we tested two modified methods and compared their screening performance with that of the conventional method. We used poly-His-tagged human epidermal growth factor receptor 2 (HER2) as a target protein and silica-coated magnetic particles (MPs) with an immobilized nickel-nitrilotriacetic acid ligand as a solid matrix. Modified method #1 (#M1) included two negative selection steps against a blocking agent (bovine serum albumin) and nude Ni-NTA MPs, after the positive selection step using immobilized HER2 on MPs in the absence of BSA. Modified method #2 (#M2) allowed the binding of phages and HER2 in solution prior to immobilizing HER2 on the MP surface. The negative selection procedure was the same between them. The binding affinity of the phages screened by #M1 and #M2 was evaluated by phage ELISA. Two phages from #M2 (#M2-4 and 5) showed the highest binding, and between them #M2-5 was selected for affinity maturation by inserting a hairpin-structured peptide between the two #M2-5 peptides. SPR study showed the HER2-binding affinity was indeed improved by ca. 2000-fold to become comparable with that of the intact antibody (trastuzumab). The modified biopanning methods combined with the dimerization maturation can be an effective way to develop antibody-mimicking peptides for affinity binding.


Assuntos
Técnicas de Visualização da Superfície Celular , Peptídeos , Receptor ErbB-2/metabolismo , Bacteriófagos , Ensaio de Imunoadsorção Enzimática , Escherichia coli/virologia , Ácido Nitrilotriacético/análogos & derivados , Compostos Organometálicos , Ligação Proteica , Dióxido de Silício
7.
Anal Chem ; 90(23): 13876-13881, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30395435

RESUMO

A basic but critical step in targeted proteomics by mass spectrometry is the separation of the targeted proteins from the complex mixture of the whole proteome by affinity purification. The bait protein is usually immobilized on the surface of a solid support to enable affinity-based purification of the targeted proteome. Here, we developed a site-specific covalent immobilization of the bait protein through affinity-guided covalent coupling (AGCC) of a single cysteine residue of an SH2 domain (utilized as an affinity tag for the protein target) with an engineered ligand peptide. Site-specific covalent immobilization of a methyllysine-binding protein HP1ß chromodomain on the agarose resin was used to purify the methyllysine proteome from the whole-protein mixture. This new bait immobilization led to a notably low background in the affinity purification step, markedly outperforming the conventional (His)6 tag-nickel nitrilotriacetic acid (Ni-NTA) immobilization method. Subsequent analysis of the purified proteome identified 275 lysine methylated sites and 184 methylated proteins from 332 HP1ß CD-binding proteins, including 30 novel methylated proteins. This work demonstrates that a robust site-specific covalent protein immobilization method is well-suited for proteomic analysis of low-abundance proteins. This method also enables the identification of new methylated proteins and methylation sites in the methyllysine proteome.


Assuntos
Lisina/análogos & derivados , Lisina/isolamento & purificação , Proteoma/química , Proteoma/isolamento & purificação , Homólogo 5 da Proteína Cromobox , Humanos , Lisina/química , Células MCF-7 , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/química , Compostos Organometálicos/química , Peptídeos/química , Domínios de Homologia de src
8.
Environ Toxicol ; 33(10): 1069-1077, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30098279

RESUMO

The present study was designed to evaluate the protective effects of hesperidin, a flavonoid on DEN initiated and Fe-NTA promoted renal carcinogenesis in Wistar rats. Renal cancer was initiated by a single i.p. injection of DEN (200 mg/kg b.wt.) and promoted with Fe-NTA (9 mg Fe/kg b.wt. i.p.) twice a week for 16 weeks. Rats were simultaneously administered with hesperidin (100 and 200 mg/kg b.wt.) for 16 consecutive weeks. The chemopreventive effect of hesperidin was assessed in terms of antioxidant activities, renal function, PGE2 level, and the expressions of COX-2 and VEGF. Hesperidin decreased the DEN and Fe-NTA induced lipid peroxidation, improved the renal function (by decreasing the levels of BUN, creatinine, and KIM-1) and restored the renal antioxidant armory (GSH, GPx, GR, SOD, and catalase). Hesperidin was also found to decrease the level of PGE2 and downregulate the expressions of COX-2 and VEGF. Histological findings further revealed the protective effects of hesperidin against DEN and Fe-NTA induced kidney damage. The result of our present findings suggest that hesperidin may be a promising modulator in preventing renal cancer possibly by virtue of its ability to alleviate oxidative stress and inhibit COX-2/PGE2 pathway.


Assuntos
Anticarcinógenos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Hesperidina/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Animais , Anticarcinógenos/farmacologia , Antioxidantes/metabolismo , Carcinogênese/induzido quimicamente , Carcinogênese/efeitos dos fármacos , Carcinoma de Células Renais/induzido quimicamente , Carcinoma de Células Renais/metabolismo , Proliferação de Células/efeitos dos fármacos , Dietilnitrosamina , Compostos Férricos , Hesperidina/farmacologia , Rim/metabolismo , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/metabolismo , Peroxidação de Lipídeos , Masculino , Ácido Nitrilotriacético/análogos & derivados , Estresse Oxidativo , Extratos Vegetais/farmacologia , Ratos Wistar
9.
J Med Chem ; 61(2): 576-582, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28460164

RESUMO

In recent years, the induction of target-protein degradation via the ubiquitin-proteasome system (UPS) mediated by small molecules has attracted attention, and this approach has applications in pharmaceutical development. However, this technique requires a ligand for the target protein that can be incorporated into tailor-made molecules, and there are many proteins for which such ligands have not been found. In this study, we developed a protein-knockdown method that recognizes a His-tag fused to a protein of interest. This strategy theoretically allows comprehensive targeting of proteins of interest by a particular molecule recognizing the tag. As expected, our hybrid molecule 10 [SNIPER(CH6)] efficiently degraded His-tagged CRABP-II and Smad2 in cells. This system provides an easy method to determine the susceptibility of proteins of interest to UPS-mediated degradation. Furthermore, we hope that this method will become an efficient tool to analyze the function of the UPS.


Assuntos
Proteólise/efeitos dos fármacos , Proteínas Recombinantes de Fusão/metabolismo , Biotina/química , Linhagem Celular , Cisteína/metabolismo , Histidina/química , Histidina/genética , Humanos , Leupeptinas/farmacologia , Maleimidas/química , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/química , Compostos Organometálicos/química , Inibidores de Proteassoma/farmacologia , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteína Smad2/genética , Proteína Smad2/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
10.
Pathol Int ; 67(11): 564-574, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29027306

RESUMO

Oxidative stress including iron excess has been associated with carcinogenesis. The level of 8-oxoguanine, a major oxidatively modified base in DNA, is maintained very low by three distinct enzymes, encoded by OGG1, MUTYH and MTH1. Germline biallelic inactivation of MUTYH represents a familial cancer syndrome called MUTYH-associated polyposis. Here, we used Mutyh-deficient mice to evaluate renal carcinogenesis induced by ferric nitrilotriacetate (Fe-NTA). Although the C57BL/6 background is cancer-resistant, a repeated intraperitoneal administration of Fe-NTA induced a high incidence of renal cell carcinoma (RCC; 26.7%) in Mutyh-deficient mice in comparison to wild-type mice (7.1%). Fe-NTA treatment also induced renal malignant lymphoma, which did not occur without the Fe-NTA treatment in both the genotypes. Renal tumor-free survival after Fe-NTA treatment was marginally different (P = 0.157) between the two genotypes. Array-based comparative genome hybridization analyses revealed, in RCC, the loss of heterozygosity in chromosomes 4 and 12 without p16INKA inactivation; these results were confirmed by a methylation analysis and showed no significant difference between the genotypes. Lymphomas showed a preference for genomic amplifications. Dlk1 inactivation by promoter methylation may be involved in carcinogenesis in both tumors. Fe-NTA-induced murine RCCs revealed significantly less genomic aberrations than those in rats, demonstrating a marked species difference.


Assuntos
Aberrações Cromossômicas/induzido quimicamente , DNA Glicosilases/deficiência , Compostos Férricos/toxicidade , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/genética , Ácido Nitrilotriacético/análogos & derivados , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ácido Nitrilotriacético/toxicidade , Estresse Oxidativo/fisiologia , Ratos , Especificidade da Espécie
11.
J Alzheimers Dis ; 60(2): 451-460, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28854504

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease characterized by a progressive cognitive impairment of patients, affecting around 12% of people older than 65 years old. WHO estimated that over 48.6 million all over the world suffer this disease. On the basis of cumulative results on our research, we have postulated the neuroimmunomodulation hypothesis that appears to provide a reasonable explanation of both the preclinical and clinical observations. In this context, the long-term activation of the innate immune system triggers an anomalous cascade of molecular signals, finally leading to tau oligomerization in the pathway to neuronal degeneration. In the present scenario of the failure of many anti-AD drugs, nutraceutical compounds provide an avenue for AD prevention and possibly as coadjuvants in the treatment of this disease. Recent discoveries point to the relevance of curcumin, a natural anti-inflammatory agent, in controlling oxidative stress and improving cholinergic function in the brain, even though the mechanisms underlying these actions are unknown. We investigated the effects of curcumin in cultures of neuronal cells. For this study, we exposed cells to prooxidant conditions, both in the presence and absence of curcumin. Our data reveal that curcumin exert a strong neuroprotective effect in N2a cells, thus preventing toxicity by oxidative agents H2O2 and Fe+3. This is supported by results that indicate that curcumin control the neurodegenerative effects of both oxidative agents, relieving cells from the loss of neuritogenic processes induced by prooxidants. In addition, curcumin was able to slow down the tau aggregation curve and disassemble tau pathological oligomeric structures. Data suggest that curcumin could be a potential compound for prevention of cognitive disorders associated with AD.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Curcumina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Curcumina/química , Relação Dose-Resposta a Droga , Compostos Férricos/toxicidade , Células HEK293 , Humanos , Peróxido de Hidrogênio/toxicidade , Camundongos , Microscopia Confocal , Microscopia Eletrônica , Neuroblastoma/patologia , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/toxicidade , Agregados Proteicos/efeitos dos fármacos , Fatores de Tempo , Proteínas tau/metabolismo , Proteínas tau/ultraestrutura
12.
Biometals ; 30(5): 699-708, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28801864

RESUMO

Iron overload disorders may be treated by chelation therapy. This study describes a novel method for isolating iron chelators from complex mixtures including plant extracts. We demonstrate the one-step isolation of curcuminoids from turmeric, the medicinal food spice derived from Curcuma longa. The method uses iron-nitrilotriacetic acid (NTA)-agarose, to which curcumin binds rapidly, specifically, and reversibly. Curcumin, demethoxycurcumin, and bisdemethoxycurcumin each bound iron-NTA-agarose with comparable affinities and a stoichiometry near 1. Analyses of binding efficiencies and purity demonstrated that curcuminoids comprise the primary iron binding compounds recovered from a crude turmeric extract. Competition of curcuminoid binding to the iron resin was used to characterize the metal binding site on curcumin and to detect iron binding by added chelators. Curcumin-Iron-NTA-agarose binding was inhibited by other metals with relative potency: (>90% inhibition) Cu2+ ~ Al3+ > Zn2+ ≥ Ca2+ ~ Mg2+ ~ Mn2+ (<20% inhibition). Binding was also inhibited by pharmaceutical iron chelators (desferoxamine or EDTA) or by higher concentrations of weak iron chelators (citrate or silibinin). Investigation of the physiological effects of iron binding by curcumin revealed that curcumin uptake by cultured cells was reduced >80% by addition of iron to the media; uptake was completely restored by desferoxamine. Ranking of metals by relative potencies for blocking curcumin uptake agreed with their relative potencies in blocking curcumin binding to iron-NTA-agarose. We conclude that curcumin can selectively bind toxic metals including iron in a physiological setting, and propose inhibition of curcumin binding to iron-NTA-agarose for iron chelator screening.


Assuntos
Curcuma/química , Curcumina/análogos & derivados , Curcumina/isolamento & purificação , Quelantes de Ferro/isolamento & purificação , Ferro/metabolismo , Alumínio/metabolismo , Alumínio/farmacologia , Animais , Ligação Competitiva , Cálcio/metabolismo , Cálcio/farmacologia , Linhagem Celular , Cromatografia de Afinidade/métodos , Cobre/metabolismo , Cobre/farmacologia , Curcumina/metabolismo , Curcumina/farmacologia , Desferroxamina/metabolismo , Desferroxamina/farmacologia , Diarileptanoides , Ácido Edético/metabolismo , Ácido Edético/farmacologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Compostos Férricos/química , Quelantes de Ferro/metabolismo , Quelantes de Ferro/farmacologia , Cinética , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Magnésio/metabolismo , Magnésio/farmacologia , Manganês/metabolismo , Manganês/farmacologia , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/química , Extratos Vegetais/química , Ratos , Zinco/metabolismo , Zinco/farmacologia
13.
J Inorg Biochem ; 177: 291-299, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28709620

RESUMO

Vanadium compounds are promising anti-diabetic agents. However, reducing the metal toxicity while keeping/improving the hypoglycemic effect is still a big challenge towards the success of anti-diabetic vanadium drugs. To improve the therapeutic potency using the anti-oxidative strategy, we synthesized new N,N-dimethylphenylenediamine (DMPD)-derivatized nitrilotriacetic acid vanadyl complexes ([VO(dmada)]). The in vitro biological evaluations revealed that the DMPD-derivatized complexes showed improved antioxidant capacity and lowered cytotoxicity on HK-2 cells than bis(maltolato)oxidovanadium (IV) (BMOV). In type II diabetic mice, [VO(p-dmada)] (0.15mmolkg-1/day) exhibited better hypoglycemic effects than BMOV especially on improving glucose tolerance and alleviating the hyperglycemia-induced liver damage. These insulin enhancement effects were associated with increased expression of peroxisome proliferator-activated receptor α and γ (PPARα/γ) in fat, activation of Akt (v-Akt murine thymoma viral oncogene)/PKB (protein kinase-B) in fat and liver, and inactivation of c-Jun NH2-terminal protein kinases (JNK) in liver. Moreover, [VO(p-dmada)] showed no tissue toxicity at the therapeutic dose in diabetic mice and the oral acute toxicity (LD50) was determined to be 1640mgkg-1. Overall, the experimental results indicated that [VO(p-dmada)] can be a potent insulin enhancement agent with improved efficacy-over- toxicity index for further drug development. In addition, the results on brain Tau phosphorylation suggested necessary investigation on the effects of vanadyl complexes on the pathology of the Alzheimer's disease in the future.


Assuntos
Complexos de Coordenação/farmacologia , Hipoglicemiantes/farmacologia , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/farmacologia , Fenilenodiaminas/farmacologia , Vanádio/química , Animais , Antioxidantes/síntese química , Antioxidantes/farmacologia , Antioxidantes/toxicidade , Glicemia/análise , Encéfalo/metabolismo , Linhagem Celular , Complexos de Coordenação/síntese química , Complexos de Coordenação/toxicidade , Intolerância à Glucose/prevenção & controle , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/toxicidade , Ligantes , Fígado/metabolismo , Masculino , Camundongos Endogâmicos ICR , Ácido Nitrilotriacético/síntese química , Ácido Nitrilotriacético/toxicidade , PPAR alfa/metabolismo , PPAR gama/metabolismo , Fenilenodiaminas/síntese química , Fenilenodiaminas/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas tau/metabolismo
14.
Chem Phys Lipids ; 205: 55-64, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28476462

RESUMO

The heterodimeric phloroglucinyl pyrone arzanol (Arz) has raised considerable interest because of its antiviral, anti-inflammatory, and antioxidant activity. We have investigated the effect of methylation of the pyrone moiety on the antioxidant activity and cytotoxicity of Arz. This manoeuvre, that left the polyphenolic moiety unscathed, was nevertheless detrimental for antioxidant activity in both the cholesterol thermal degradation- and the Cu2+-induced liposome oxidation assays, providing evidence of structure-activity relationships that go beyond the preservation of the polyphenolic pharmacophore. The antioxidant activity of Arz was retained also in the Fe-NTA model of in vivo oxidative stress, with protective effect on the oxidative degradation of plasmatic lipids, unsaturated fatty acids and cholesterol. Both Arz and methylarzanol (Me-Arz) were devoid of toxic effect on colonic differentiated Caco-2 cells up to 100µM, but significantly reduced cancer Caco-2 cell viability at lower dosages. Arz could also selectively reduce viability of other cancer cell lines, [murine melanoma cells (B16F10 cells), human cervical carcinoma cells (HeLa cells)], suggesting that it can act as a selective modulator of cell processes typical of cancer cells. Taken together, our results qualify Arz as a lead structure for further in vivo investigation of its pharmacological potential.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Floroglucinol/análogos & derivados , Pironas/química , Pironas/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Descoberta de Drogas , Compostos Férricos/química , Helichrysum/química , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Metilação , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/química , Oxirredução , Estresse Oxidativo , Floroglucinol/química , Floroglucinol/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Relação Estrutura-Atividade
15.
Biometals ; 30(2): 261-275, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28204978

RESUMO

The use of protonated N-heterocyclic compound, i.e. 2,2'-bipyridinium cation, [bpyH+], enabled to obtain the new nitrilotriacetate oxidovanadium(IV) salt of the stoichiometry [bpyH][VO(nta)(H2O)]H2O. The X-ray measurements have revealed that the compound comprises the discrete mononuclear [VO(nta)(H2O)]- coordination ion that can be rarely found among other known compounds containing nitrilotriacetate oxidovanadium(IV) moieties. The antitumor activity of [bpyH][VO(nta)(H2O)]H2O and its phenanthroline analogue, [phenH][VO(nta)(H2O)](H2O)0.5, towards human osteosarcoma cell lines (MG-63 and HOS) has been assessed (the LDH and BrdU tests) and referred to cis-Pt(NH3)2Cl2 (used as a positive control). The compounds exert a stronger cytotoxic effect on MG-63 and HOS cells than in untransformed human osteoblast cell line. Thus, the [VO(nta)(H2O)]- containing coordination compounds can be considered as possible antitumor agents in the osteosarcoma model of bone-related cells in culture.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Ácido Nitrilotriacético/farmacologia , Osteoblastos/efeitos dos fármacos , Compostos de Vanádio/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Relação Dose-Resposta a Droga , Humanos , Ácido Nitrilotriacético/análogos & derivados , Osteoblastos/patologia , Potenciometria , Compostos de Vanádio/química
16.
J Complement Integr Med ; 14(1)2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28214348

RESUMO

Background The present study focused on the antioxidant, phenolic profile and free radical scavenging-mediated protective effect of leaves extracts of Syzygium guineense var. macrocarpum against ferric nitriloacetate-induced stress in the liver, heart, kidney and brain tissues of Wistar rats homogenates. Methods Spectrophotometric standardized methods were used to determine the free radical scavenging potential, antioxidant and protective properties of plant extracts on rat homogenates. Results All the extracts showed a concentration-dependent free radical quenching potential, and the ability to protect all the tested organs by inhibiting the lipid peroxidation and potentiating or restoring the activity of enzymatic and non enzymatic markers. The polyphenolic profile revealed the presence of at least one simple phenolic acid (gallic, caffeic, para-coumaric acid) although the majority (6 out of 14) of the compounds used as standard are present in the aqueous and aqueous-ethanol extracts. Conclusions Ethanolic extract of leaves of S. guineense var macrocarpum (SGETOH) exhibited the highest phenol content and appeared as the best extract taking into consideration the antioxidant and organo-protective activities tested.


Assuntos
Antioxidantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Syzygium/química , Animais , Encéfalo/efeitos dos fármacos , Compostos Férricos , Coração/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Ácido Nitrilotriacético/análogos & derivados , Fenóis/análise , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/análise , Polifenóis/farmacologia , Substâncias Protetoras/análise , Substâncias Protetoras/farmacologia , Ratos Wistar
17.
Inflammopharmacology ; 24(5): 233-251, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27628241

RESUMO

Melastoma malabathricum Linn (MM) has high valued for its commercial significance. Indian market (northeast) has great demand for the plants, which extended, its use as a traditional home remedy due to its anti-inflammatory effects. In this study, we scrutinize the therapeutic and protective effect of MM against diethylnitrosamine (DEN) and ferric nitrilotriacetate (Fe-NTA)-induced renal carcinogenesis, renal hyperproliferation, and oxidative stress in rats. Liquid chromatography mass spectroscopy (LC-MS) was used for identification of phytoconstituents. Administration of DEN confirmed the initiation the renal carcinogenesis via enhancing the expansion of tumor incidence. Intraperitoneally, administration of Fe-NTA boost the antioxidant enzymes (phase I), viz., superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and phase II, viz., quinone reductase (QR) and glutathione-S-transferase (GST). It also increased the content of renal lipid peroxidation (LPO), hydrogen peroxidase (H2O2) with decrease content in glutathione content (GSH). It also increased the renal biochemical and non-biochemical parameter. It also confirmed the augment the level of thymidine [3H] incorporation into renal DNA, ornithine decarboxylase (ODC) activity and increased the generation of proinflammatory (TNF-α, IL-6 and IL-ß) and inflammatory mediator (PGE2). We also analyzed the macroscopic and histologic of renal tissue. In addition, the effect of phytoconstituent of MM extract was evaluated in silico and free radical scavenging activity against the DPPH and ABTS free radicals. LC-MS confirmed the presence of quercetin >gallic acid in MM extract. Renal carcinogenesis rats treated with MM (100, 250, and 500 mg/kg) confirmed the significantly (P < 0.001) protective effect via reduction the antioxidant (phase I and phase II) enzymes, biochemical parameter and restore the proinflammatory and inflammatory mediator at dose dependent manner. MM altered the ODC and thymidine activity in renal DNA. The chemoprotective effect of MM was confirmed via decreased the renal tumor incidence, which was confirmed by the macroscopic and histopathological observation. Consequently, our result suggests that MM is a potent chemoprotective agent and suppresses DEN+ Fe-NTA-induced renal carcinogenesis, inflammatory reaction, and oxidative stress injury in Wister rats.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/metabolismo , Melastomataceae , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Compostos Férricos/toxicidade , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Neoplasias Renais/induzido quimicamente , Masculino , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/toxicidade , Estresse Oxidativo/fisiologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Distribuição Aleatória , Ratos , Ratos Wistar , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/fisiologia
18.
BMC Complement Altern Med ; 16(1): 315, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27561333

RESUMO

BACKGROUND: Overconsumption of oxygen in mammalian cells often lead to the production of reactive oxygen species (ROS) resulting from different mechanisms. Escape of scavenging enzymes/components or nutritional failure are the most important origins. Plant-derived molecules may protect biological molecules either by quenching free radicals, delaying or preventing the ROS formation or by restoring antioxidant enzymes activities. The present study assessed the antioxidant, phenolic profile and protective effect of barks extracts of Syzyguim guineense var macrocarpum against ferric nitriloacetate-induced stress in the liver, heart kidney and brain tissues of wistar rat homogenates. METHODS: Three extracts (aqueous, ethanol and aqueous-ethanol) from the barks of S. guineense var macrocarpum were used in this study. The spectrophotometric standardized methods were used to determine the free radical scavenging and antioxidant potential of the extracts. The protective properties of these plant extracts were also investigated as well as the quantification of secondary metabolites content (total phenolic, flavonoids and flavonols content). The HPLC method helped for characterizing phenolic compounds present in these extracts. RESULTS AND DISCUSSION: All the extracts exhibited a free radical scavenging potential in a concentration dependent manner which varied from 15.18 ± 0.80 to 97.15 ± 0.71 % depending to the type of extract and the method used. The ethanol extract had the higher phenolic content (432.85 mg QE/g extract), including total flavonoids (961.66 mg QE/g extract) and flavonols content (25.12 mg QE/g extract) and higher total antioxidant capacity. Among the phenolic compounds present in the extracts, the HLPC profile revealed the presence of syringic acid and apigenin in all the extracts. The extracts demonstrated their protective effect mostly in liver and brain homogenates by delaying or preventing lipid peroxidation, restoring enzymatic activities and enhancing glutathione levels. CONCLUSION: The overall results demonstrated that the extracts exhibited significant antioxidant and protective effects in liver and brain liver homogenates.


Assuntos
Compostos Férricos/toxicidade , Ácido Nitrilotriacético/análogos & derivados , Estresse Oxidativo/efeitos dos fármacos , Casca de Planta/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Syzygium/química , Animais , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Ácido Nitrilotriacético/toxicidade , Extratos Vegetais/química , Substâncias Protetoras/química , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
19.
Arch Biochem Biophys ; 606: 1-9, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27403965

RESUMO

Chrysin (CH) is natural, biologically active compound, belongs to flavoniod family and possesses diverse pharmacological activities as anti-inflammatory, anti-oxidant and anti-cancer. It is found in many plants, honey and propolis. In the present study, we investigated the chemopreventive efficacy of CH against N-nitrosodiethylamine (DEN) initiated and Fe-NTA induced precancerous lesions and its role in regulating oxidative injury, hyperproliferation, tumor incidences, histopathological alterations, inflammation, and apoptosis in the kidneys of Wistar rats. Renal cancer was initiated by single intraperitoneal (i.p.) injection of DEN (200 mg/kg bw) and promoted by twice weekly injection of ferric nitrilotriacetate (Fe-NTA) 9 mg Fe/kg bw for 16 weeks. CH attenuated Fe-NTA enhanced renal lipid peroxidation, serum toxicity markers and restored renal anti oxidant armory significantly. CH supplementation suppressed the development of precancerous lesions via down regulation of cell proliferation marker like PCNA; inflammatory mediators like TNF-α, IL-6, NFkB, COX-2, iNOS; tumor incidences. CH up regulated intrinsic apoptotic pathway proteins like bax, caspase-9 and caspase-3 along with down regulation of Bcl-2 triggering apoptosis. Histopathological and ultra structural alterations further confirmed biochemical and immunohistochemical results. These results provide powerful evidence for the chemopreventive efficacy of CH against chemically induced renal carcinogenesis possibly by modulation of multiple molecular pathways.


Assuntos
Flavonoides/química , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/prevenção & controle , Lesões Pré-Cancerosas/fisiopatologia , Animais , Anticarcinógenos/química , Antioxidantes/química , Apoptose , Carcinogênese , Proliferação de Células , Compostos Férricos , Inflamação , Rim/patologia , Neoplasias Renais/fisiopatologia , Peroxidação de Lipídeos , Masculino , Ácido Nitrilotriacético/análogos & derivados , Estresse Oxidativo , Lesões Pré-Cancerosas/induzido quimicamente , Ratos , Ratos Wistar , Regulação para Cima
20.
Proc Natl Acad Sci U S A ; 113(12): E1645-54, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-26929326

RESUMO

The surface of a living cell provides a platform for receptor signaling, protein sorting, transport, and endocytosis, whose regulation requires the local control of membrane organization. Previous work has revealed a role for dynamic actomyosin in membrane protein and lipid organization, suggesting that the cell surface behaves as an active composite composed of a fluid bilayer and a thin film of active actomyosin. We reconstitute an analogous system in vitro that consists of a fluid lipid bilayer coupled via membrane-associated actin-binding proteins to dynamic actin filaments and myosin motors. Upon complete consumption of ATP, this system settles into distinct phases of actin organization, namely bundled filaments, linked apolar asters, and a lattice of polar asters. These depend on actin concentration, filament length, and actin/myosin ratio. During formation of the polar aster phase, advection of the self-organizing actomyosin network drives transient clustering of actin-associated membrane components. Regeneration of ATP supports a constitutively remodeling actomyosin state, which in turn drives active fluctuations of coupled membrane components, resembling those observed at the cell surface. In a multicomponent membrane bilayer, this remodeling actomyosin layer contributes to changes in the extent and dynamics of phase-segregating domains. These results show how local membrane composition can be driven by active processes arising from actomyosin, highlighting the fundamental basis of the active composite model of the cell surface, and indicate its relevance to the study of membrane organization.


Assuntos
Citoesqueleto de Actina/metabolismo , Actomiosina/metabolismo , Membrana Celular/metabolismo , Proteínas de Membrana/metabolismo , Citoesqueleto de Actina/ultraestrutura , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Bactérias/genética , Polaridade Celular , Quelantes , Galinhas , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Técnicas In Vitro , Bicamadas Lipídicas , Proteínas Luminescentes/genética , Microscopia Eletrônica , Modelos Biológicos , Níquel , Ácido Nitrilotriacético/análogos & derivados , Fosfatidilcolinas , Fosfatidiletanolaminas , Ligação Proteica , Proteínas Recombinantes de Fusão/metabolismo , Propriedades de Superfície
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