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1.
Acta Pharmacol Sin ; 44(8): 1612-1624, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36747104

RESUMO

Suprachiasmatic nucleus (SCN) in mammals functions as the master circadian pacemaker that coordinates temporal organization of physiological processes with the environmental light/dark cycles. But the causative links between SCN and cardiovascular diseases, specifically the reparative responses after myocardial infarction (MI), remain largely unknown. In this study we disrupted mouse SCN function to investigate the role of SCN in cardiac dysfunction post-MI. Bilateral ablation of the SCN (SCNx) was generated in mice by electrical lesion; myocardial infarction was induced via ligation of the mid-left anterior descending artery (LAD); cardiac function was assessed using echocardiography. We showed that SCN ablation significantly alleviated MI-induced cardiac dysfunction and cardiac fibrosis, and promoted angiogenesis. RNA sequencing revealed differentially expressed genes in the heart of SCNx mice from D0 to D3 post-MI, which were functionally associated with the inflammatory response and cytokine-cytokine receptor interaction. Notably, the expression levels of insulin-like growth factor 2 (Igf2) in the heart and serum IGF2 concentration were significantly elevated in SCNx mice on D3 post-MI. Stimulation of murine peritoneal macrophages in vitro with serum isolated from SCNx mice on D3 post-MI accelerated the transition of anti-inflammatory macrophages, while antibody-mediated neutralization of IGF2 receptor blocked the macrophage transition toward the anti-inflammatory phenotype in vitro as well as the corresponding cardioprotective effects observed in SCNx mice post-MI. In addition, disruption of mouse SCN function by exposure to a desynchronizing condition (constant light) caused similar protective effects accompanied by elevated IGF2 expression on D3 post-MI. Finally, mice deficient in the circadian core clock genes (Ckm-cre; Bmal1f/f mice or Per1/2 double knockout) did not lead to increased serum IGF2 concentration and showed no protective roles in post-MI, suggesting that the cardioprotective effect observed in this study was mediated particularly by the SCN itself, but not by self-sustained molecular clock. Together, we demonstrate that inhibition of SCN function promotes Igf2 expression, which leads to macrophage transition and improves cardiac repair post-MI.


Assuntos
Ritmo Circadiano , Infarto do Miocárdio , Animais , Camundongos , Ritmo Circadiano/genética , Macrófagos , Mamíferos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/metabolismo , Núcleo Supraquiasmático/metabolismo
2.
Molecules ; 23(6)2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29799496

RESUMO

A novel 36-metallacrown-6 complex [CuL(N(CN)2)(PF6)]6∙0.5H2O 1 was achieved using a tridendate ligand, 1,4,7-triisopropyl-1,4,7-triazacyclononane (L), and a flexible ligand, dicyanamide in MeOH. The µ1,5 bridging models of the dicyanamide ligand linked the macrocycle to form in a specific size with the chair conformation. The anion was important to form this 36-metallacrown-6 complex, as change was obtained with the larger anion BPh4-, binuclear copper compound 2. The magnetic property indicates that slightly ferromagnetic interactions resulted from a superexchange mechanism. DNA binding properties were also studied. UV and fluorescence spectra showed that complex 1 could bind with DNA.


Assuntos
Cobre/química , Cianetos/química , DNA/química , Compostos Heterocíclicos/química , Compostos Organometálicos/química , Sítios de Ligação , Cristalografia por Raios X , Cianetos/síntese química , Compostos Heterocíclicos/síntese química , Campos Magnéticos , Conformação Molecular , Compostos Organometálicos/síntese química
3.
Inorg Chem ; 50(9): 4006-15, 2011 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-21443177

RESUMO

Two novel complexes, [{Mn(salen)}(2){Mn(salen)(CH(3)OH)}{Cr(CN)(6)}](n)·2nCH(3)CN·nCH(3)OH (1) and [Mn(5-Clsalmen)(CH(3)OH)(H(2)O)](2n)[{Mn(5-Clsalmen)(µ-CN)}Cr(CN)(5)](n)·5.5nH(2)O (2) (salen(2-) = N,N'-ethylene-bis(salicylideneiminato) dianion; 5-Clsalmen(2-) = N,N'-(1-methylethylene)-bis(5-chlorosalicylideneiminato) dianion), were synthesized and structurally characterized by X-ray single-crystal diffraction. The structural analyses show that complex 1 consists of one-dimensional (1D) alternating chains formed by the [{Cr(CN)(6)}{Mn(salen)}(4){Mn(salen)(CH(3)OH)}(2)](3+) heptanuclear cations and [Cr(CN)(6)](3-) anions. While in complex 2, the hexacyanochromate(III) anion acts as a bis-monodentate ligand through two trans-cyano groups to bridge two [Mn(5-Clsalmen)](+) cations to form a straight chain. The magnetic analysis indicates that complex 1 shows three-dimensional (3D) antiferromagnetic ordering with the Néel temperature of 5.0 K, and it is a metamagnet displaying antiferromagnetic to ferromagnetic transition at a critical field of about 2.6 kOe at 2 K. Complex 2 behaves as a molecular magnet with Tc = 3.0 K.

4.
Inorg Chem ; 49(5): 2047-56, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20067273

RESUMO

Three complexes, [Mn(salphen)(H(2)O)](2)[Fe(CN)(5)(NO)] x 2 CH(3)OH (1) (salphen = N,N'-phenylenebis(salicylideneiminato) dianion), [Mn(naphtmen)(CH(3)OH)](2)[Fe(CN)(5)(NO)] (2) (naphtmen = N,N'-(1,1,2,2-tetramethylethylene)bis(naphthylideneiminato) dianion), and {[Mn(salen)](2)[Fe(CN)(5)(NO)] x H(2)O}(n) (3) (salen = N,N'-ethylene-bis(salicylideneiminato) dianion), were synthesized and structurally characterized by X-ray single-crystal diffraction. The structural analyses show that complexes 1 and 2 consist of the discrete linear trinuclear [Mn(SB)](2)[Fe(CN)(5)(NO)] units (SB = salphen for 1, naphtmen for 2); in complex 3, the nitroprusside anion coordinates to the axial sites of the four [Mn(salen)](+) entities through its four cyano nitrogen atoms, providing a two-dimensional network. The magnetic analysis indicates that the nitroprusside bridging ligand propagates a very weak antiferromagnetic exchange and single-ion anisotropy (D) plays an important role in the overall magnetic properties. Different from complexes 2 and 3, complex 1 shows a typical spin-flop transition with a critical field of 20 kOe.

5.
Inorg Chem ; 49(5): 2525-9, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20131809

RESUMO

A 3D nickel-organic framework formulated as {[Ni(2)(fum)(2)(bpt)(2)(H(2)O)] x 3 H(2)O}(n) (1), built from a mixed fumaric ion (fum), 1H-3,5-bis(4-pyridyl)-1,2,4-triazole (bpt), and nickel salt, has been hydrothermally synthesized and characterized. Compound 1, having a Ni-fum chain structure in which the chains are pillared by the bpt spacers in a 3D "brick-wall"-like architecture, exhibits canted antiferromagnetism at 5.0 K. Below this temperature, slow relaxation is observed from the alternating-current susceptibility measurements corresponding to the spin-glass-like behavior.

6.
Chem Commun (Camb) ; (21): 3113-5, 2009 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-19462104

RESUMO

The first porous 3D [Ln-Fe] heterometal-organic frameworks incorporating high-spin Fe(ii) ions were structurally characterized with fascinating 1D channels and higher thermal stability: the robust frameworks still keep intact on removing free H(2)O or adsorbing C(2)H(5)OH, and the luminescence of [Eu-Fe] complex displays selective detection of Mg(2+).

7.
Inorg Chem ; 48(18): 8890-6, 2009 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-19691302

RESUMO

Five new complexes based on rare-earth-radical [Ln(hfac)(3)(NIT-5-Br-3py)](2) (Ln = Pr (1), Sm (2), Eu (3), Tb (4), Tm (5); hfac = hexafluoroacetylacetonate; NIT-5-Br-3py = 2-(4,4,5,5-tetramethyl-3-oxylimidazoline-1-oxide)-5-bromo-3-pyridine) have been synthesized and characterized by X-ray crystal diffraction. The single-crystal structures show that these complexes have similar structures, in which a NIT-5-Br-3py molecule acts as a bridging ligand linking two Ln(III) ions through the oxygen atom of the N-O group and nitrogen atom from the pyridine ring to form a four-spin system. Both static and dynamic magnetic properties were measured for complex 4, which exhibits single-molecule magnetism behavior.

8.
Chem Commun (Camb) ; (47): 6414-6, 2008 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-19048173

RESUMO

A novel octanuclear hydroxonickel(II) complex possessing a unprecedented cube molecular structure with eight Ni(II) ions at each vertex, six micro4-OH- groups closing each face and twelve exo-bidentate pyrazolate ligands (micro2-pz) spanning each edge, has been synthesized and its magnetic properties investigated.


Assuntos
Magnetismo , Níquel/química , Hidroxilação , Ligantes , Modelos Moleculares , Estrutura Molecular , Pirazóis/química , Estereoisomerismo
9.
Inorg Chem ; 47(19): 8748-56, 2008 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-18722421

RESUMO

Lanthanide coordination polymers were synthesized from Pr(III), Nd(III), and Gd(III) salts; 2-hydroxynicotinic acid (Hnica); and MnSO 4.H 2O under hydrothermal conditions. In the absence of (CH 3) 3CCOONa, 1D polymers with an infinite Ln(III)-O-Ln(III) chain structure, [Pr(Hnica)(H 2O) 2SO 4] n ( 1), [Nd(Hnica)(H 2O) 2SO 4] n ( 2), and [Gd(Hnica)(H 2O) 2SO 4] n ( 3), were generated. When (CH 3) 3CCOONa was added to the synthetic systems, 2D coordination polymers {[Pr 3(Hnica) 6(H 2O) 9].3H 2O.SO 4.NO 3} n ( 4), {[Nd 3(Hnica) 6(H 2O) 9].3H 2O.SO 4.NO 3} n ( 5), and {[Gd(Hnica) 2(H 2O) 2]ClO 4.H 2O} n ( 6) were obtained. Complexes 4 and 5 both exhibit Kagome lattice structure, while 6 displays a rhombic grid structure. All complexes were characterized by elemental analysis, IR spectra, UV-vis spectra, and X-ray single-crystal diffraction. The variable-temperature magnetic susceptibility studies reveal ferromagnetic interactions between gadolinium(III) ions in 3 and 6 and antiferromagnetic interactions in 1, 2, 4, and 5.

10.
Inorg Chem ; 47(23): 11057-61, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18959373

RESUMO

Four new heterometallic coordination polymers have been successfully synthesized, namely, {[Ho(2)(HCAM)(6)Mn(3)(H(2)O)(12)].17.5H(2)O}(n) (1), {[Er(2)(HCAM)(6)Mn(3)(H(2)O)(12)].17.5H(2)O}(n) (2), {[Ho(2)(HCAM)(6)Zn(3)(H(2)O)(12)].26H(2)O}(n) (3), and {[Er(2)(HCAM)(6)Zn(3)(H(2)O)(12)].26H(2)O}(n) (4) (H(3)CAM = chelidamic acid). X-ray crystallographic studies reveal that coordination polymers 1-4 are isostructural and crystallized in the rhombohedral crystal system, space group R3. These compounds comprise a 2D honeycomb-type framework. A 2D water sheet is first found in 3 and 4, which exhibits a novel topological motif. The magnetic results for 1-4 show that ferromagnetic interactions take place between the Ho(3+)/Er(3+) and Mn(2+) ions within 1 and 2.

12.
J Inorg Biochem ; 101(2): 196-202, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17140667

RESUMO

One new binuclear Co(II) complex of N,N,N',N'-tetrakis(2-benzimidazolylmethyl)-2-hydroxyl-1,3-diaminopropane (HL), [Co(2)L(mu(2)-Cl)](ClO(4))(2) x 3CH(3)CN x C(2)H(5)OC(2)H(5) (1), has been synthesized and its crystal structure and magnetic properties are shown. In 1, each Co(II) atom has a distorted trigonal bipyramidal geometry with a N(3)OCl donor set. The central two Co(II) atoms are bridged by one alkoxo-O atom and one Cl atom with the Co1-Co2 separation of 3.239 A. Susceptibility data of 1 indicate strong intramolecular antiferromagnetic coupling of the high-spin Co(II) atoms. In this paper, the interaction with calf thymus DNA was investigated by UV absorption and fluorescent spectroscopy. Results show the complex binds to ct-DNA with a intercalative mode. The interaction between complex 1 and pBR322 DNA has also been investigated by submarine gel electrophoresis, noticeably, the complex exhibits effective DNA cleavage activity in the absence of any external agents.


Assuntos
Cobalto/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Animais , Bovinos , Cristalografia por Raios X , DNA/efeitos dos fármacos , DNA/metabolismo , Desoxirribonucleases/metabolismo , Hidrólise , Técnicas In Vitro , Magnetismo , Estrutura Molecular , Compostos Organometálicos/farmacologia , Espectrometria de Fluorescência , Espectrofotometria , Espectrofotometria Ultravioleta
14.
Eur J Med Chem ; 114: 244-56, 2016 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-26994692

RESUMO

Four copper(II) complexes with chiral Schiff-base ligands, [Cu(R-L(1))2]·EtOAc (1) and [Cu(S-L(1))2]·EtOAc (2), [Cu(R-L(2))2]·EtOAc (3) and [Cu(S-L(2))2]·EtOAc (4), (R/S-HL(1) = (R/S)-(1-naththyl)-salicylaldimine, R/S-HL(2) = (R/S)-(1-naththyl)-3-methoxysalicylaldimine, EtOAc = ethyl acetate) were synthesized to serve as artificial nucleases and anticancer drugs. All complexes and R/S-HL(1) ligands were structurally characterized by X-ray crystallography. The interaction of these complexes with CT-DNA was researched via several spectroscopy methods, which indicates that complexes bind to CT-DNA by moderate intercalation binding mode. Moreover, DNA cleavage experiments revealed that the complexes exhibited remarkable DNA cleavage activities in the presence of H2O2via the generation of hydroxyl radical. Particularly, complex 4 also could nick DNA with the production of (1)O2. And all complexes exhibited excellent cytotoxicity to MDA-MB-231, A549 and Hela human cancer cells in micromole magnitude. Furthermore, complex 4 exhibited comparable cytotoxic effect to cisplatin against the proliferation of MDA-MB-231 and A549 cancer cells, as well as showed better anticancer ability to the three cancer cells than the other complexes. The results of cell cycle analysis indicated that complexes 3-4 could induce G2/M phase cell cycle arrest. Furthermore, MDA-MB-231 cells treated with 3 and 4 were subjected to apoptosis and death by generation of ROS and the activation of caspase-3. Interestingly, the chiral complexes 3 and 4 may induce cell apoptosis through extrinsic and mitochondrial intrinsic pathway, respectively.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cobre/farmacologia , DNA/química , Compostos Organometálicos/farmacologia , Bases de Schiff/química , Soroalbumina Bovina/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Sítios de Ligação/efeitos dos fármacos , Bovinos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cobre/química , Cristalografia por Raios X , Clivagem do DNA , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Bases de Schiff/síntese química , Bases de Schiff/farmacologia , Relação Estrutura-Atividade
15.
Dalton Trans ; 45(25): 10233-48, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27230103

RESUMO

A series of Ni(II), Co(II), Zn(II) and Cd(II) complexes with polytopic Schiff base ligands have been synthesized. The single-crystal X-ray crystallography results show that tetranuclear complexes have common face-shared defective dicubane cores, whereas trinuclear Cd(II) complexes are almost linear entities. Synthesis methods (solvent evaporation and hydrothermal synthesis), reaction conditions (pH, solvents and dosage) and coligands (azide, methanol, chloride and acetate) play vital roles in determining the final structure of the complexes and therefore their magnetic properties. In complexes , the terminal and central M(2+) ions are connected through mixed bridges, µ-phenoxido/µ1,1,1-X and µ-Oalphatic/µ1,1,1-X, while central two M(2+) ions are linked by double bridges, µ1,1,1-X (X = azido and methoxido groups for and respectively). For complex , two central Ni(II) ions are connected through two µ1,1,1-N3(-) which is relatively less reported. For complexes , there are two kinds of Cd(II), the centre Cd(II) ions are eight-coordinated with triangle dodecahedral geometries, while the two side Cd(II) ions are six-coordinated with trigonal prism geometries using chlorides or acetates as terminal ligands. Magnetic susceptibility measurements (χM) for compounds have been performed, and they reveal predominant ferromagnetic exchange interactions in Co(II) and Ni(II) tetramers. The photoluminescence studies show that the Zn(II) complex and three Cd(II) complexes have strong fluorescence, and the lifetimes are measured to be in the 10(2) nanosecond timescale.

16.
Chem Commun (Camb) ; (39): 4979-81, 2005 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-16205820

RESUMO

A new Prussian-blue type molecular magnet containing a paramagnetic [Cr(CN)5(NO)]3- building block has been synthesized and characterized; the observed magnetic behavior displays the nature of a ferrimagnet.

17.
Eur J Gastroenterol Hepatol ; 27(3): 335-43, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25563138

RESUMO

BACKGROUND: Although the therapy of varices in liver cirrhosis has improved, the mortality during a variceal hemorrhage episode remains high. Patients with hepatic venous pressure gradient (HVPG) greater than 12 mmHg have been identified as being at a higher risk for the first hemorrhage episode. AIMS: The aim of this study was to find an accurate method to predict HVPG greater than 12 mmHg. METHODS: A total of 150 hepatitis B patients with liver cirrhosis were enrolled and analyzed retrospectively. The patients were randomly divided into the experiment group and the validation group. The experiment group was used to construct a model to predict HVPG greater than 12 mmHg. The validation group was used to verify the predictive equation. RESULTS: The predictive model combined with the liver/spleen volume ratio and classification of varices was constructed to predict HVPG greater than 12 mmHg. The area under the curve of this predictive equation was 0.919. The values of sensitivity, specificity, positive predictive value, and negative predictive value were 92.9, 87.0, 89.7, and 90.9%, respectively. The following equation was used to calculate the HVPG score: HVPG score = 13.651 - 6.187×ln (liver/spleen volume)+2.755×[classification of varices score (classification of varices : small, 1; large; 2]. CONCLUSION: The new model combining the liver/spleen volume ratio and classification of varices can accurately predict HVPG in hepatitis B patients with cirrhosis.


Assuntos
Varizes Esofágicas e Gástricas/fisiopatologia , Veias Hepáticas/fisiopatologia , Hepatite B Crônica/complicações , Cirrose Hepática/fisiopatologia , Fígado/patologia , Baço/patologia , Adulto , Distribuição por Idade , Idoso , Varizes Esofágicas e Gástricas/patologia , Varizes Esofágicas e Gástricas/virologia , Feminino , Hemorragia Gastrointestinal/patologia , Hemorragia Gastrointestinal/fisiopatologia , Hemorragia Gastrointestinal/virologia , Hepatite B Crônica/patologia , Hepatite B Crônica/fisiopatologia , Humanos , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Valor Preditivo dos Testes , Estudos Retrospectivos , Pressão Venosa/fisiologia
18.
Eur J Gastroenterol Hepatol ; 27(8): 914-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25856686

RESUMO

BACKGROUND: Patients with cirrhosis have a high incidence of portal vein thrombosis (PVT), and optimal management of PVT in cirrhotic patients remains unclear. Currently, there is no paper on optimal doses of enoxaparin for the management of PVT with cirrhosis. AIMS: To evaluate the efficacy and safety of anticoagulation therapy with different doses of enoxaparin for PVT in cirrhotic patients with hepatitis B. MATERIALS AND METHODS: Sixty-five patients with hepatitis B-related cirrhosis and acute PVT were treated by different doses of enoxaparin. All the patients were assigned randomly to two groups: one group received enoxaparin 1 mg/kg subcutaneously every 12 h and the other group received enoxaparin 1.5 mg/kg subcutaneously every 24 h. Clinical, biochemical evaluation, Doppler ultrasound, and contrast-enhanced computed tomography were performed during the anticoagulation treatment. RESULTS: Of the 65 patients, 51 patients (78.5%) achieved complete/partial recanalization of PVT after 6 months of anticoagulation therapy. Child-Pugh scores were lower in the 51 patients who achieved complete/partial recanalization than those of the 14 nonresponders (P<0.01). No patients showed variceal bleeding during anticoagulation therapy in the two groups. The rates of nonvariceal bleeding with the use of 1.5 mg/kg every 24 h (23.5%) were higher than those with the use of 1 mg/kg every 12 h (6.4%). CONCLUSION: Anticoagulation therapy with different doses of enoxaparin for PVT in hepatitis B patients with cirrhosis is efficient and safe, and 1 mg/kg enoxaparin subcutaneously every 12 h is a better anticoagulation regimen in the treatment of PVT in cirrhotic patients.


Assuntos
Enoxaparina/administração & dosagem , Fibrinolíticos/administração & dosagem , Hepatite B/complicações , Cirrose Hepática/virologia , Veia Porta , Trombose Venosa/tratamento farmacológico , Adulto , China , Esquema de Medicação , Enoxaparina/efeitos adversos , Feminino , Fibrinolíticos/efeitos adversos , Hemorragia/induzido quimicamente , Hepatite B/diagnóstico , Humanos , Injeções Subcutâneas , Cirrose Hepática/diagnóstico , Masculino , Pessoa de Meia-Idade , Flebografia/métodos , Veia Porta/diagnóstico por imagem , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia Doppler , Trombose Venosa/diagnóstico , Trombose Venosa/virologia
19.
Dalton Trans ; 44(20): 9516-27, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25919814

RESUMO

Six novel copper(ii) complexes of [CuCl]ClO4 (), [Cu(acac)]PF6 (), [CuCl]2(PF6)2 (), [CuCl]2(PF6)2 (), [Cu(acac)]PF6 () and [Cu(acac)]PF6 (), ( = 1-naphthyl-N,N-[bis(2-pyridyl)methyl]amine, = R/S-1-naphthyl-N,N-[bis(2-pyridyl)methyl]ethanamine, acac = diacetone) were synthesized to serve as artificial nucleases. All complexes were structurally characterized using X-ray crystallography. The crystal structures showed the presence of distorted square-planar CuLCl (, and ) and distorted tetragonal-pyramidal CuL(acac) (, and ) geometry. The interaction of these complexes with calf thymus DNA (CT-DNA) was researched by means of several spectroscopy methods, which indicated that the complexes were bound to CT-DNA by an intercalation binding mode. DNA cleavage experiments revealed that the complexes exhibited remarkable DNA cleavage activities in the presence of H2O2, and single oxygen ((1)O2) or hydroxyl radicals may serve as the major cleavage active species. In particular, the in vitro cytotoxicity of the complexes on four human cancer cell lines (HeLa, MCF-7, Bel-7404 and HepG-2) demonstrated that the six compounds had broad-spectrum anti-cancer activity with low IC50 values. The stronger cytotoxicity and DNA cleavage activity of the chiral enantiomers compared with chiral analogues verified the influence of chirality on the antitumor activity of complexes. Meanwhile, the protein binding ability was revealed by quenching of tryptophan emission with the addition of complexes using BSA as a model protein. The results indicated that the quenching mechanism of BSA by the complexes was a static process.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Cobre/química , DNA/metabolismo , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Soroalbumina Bovina/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Bovinos , Linhagem Celular Tumoral , Técnicas de Química Sintética , DNA/química , Clivagem do DNA/efeitos dos fármacos , Humanos , Modelos Moleculares , Conformação Molecular , Compostos Organometálicos/química , Compostos Organometálicos/metabolismo , Estereoisomerismo
20.
J Inorg Biochem ; 145: 19-29, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25597488

RESUMO

Three new Co(II) complexes, [Co4(L)2(µ3-CrO4)2](ClO4)2·2CH3CN (1), [Co2(L)(µ2-na)(H2O)](ClO4)2 (2) and [Co2(L)(µ2-ba)](ClO4)2·0.5CH3CN (3) (Hna=nicotinic acid, Hba=benzoic acid, HL=N,N,N',N'-tetrakis (2-quinolylmethyl)-1,3-diaminopropan-2-ol), have been synthesized and characterized by various physicochemical techniques. The Co(II) centers are connected by endogenous alkoxy bridge from L(-) and various extrinsic auxiliary linkers, some of which display coordination number asymmetry (5, 6-coordinated for 1 and 2; 5, 5-coordinated for 3). It is worth mentioning that complex 1 contains two rare reported µ3-η(1), η(1), η(1)-CrO4(2-) moieties. Susceptibility data of three complexes indicated intramolecular antiferromagnetic coupling of high-spin Co(II) atoms with exchange integral values (J) -14.94 cm(-1), -11.26 cm(-1) and -13.66 cm(-1) for 1, 2 and 3, respectively. Interaction of compounds with calf thymus DNA (CT-DNA) have been investigated by absorption spectral titration, ethidium bromide (EB) displacement assay and viscosity measurement, which revealed that compounds bound to CT-DNA with a moderate intercalative mode, accompanied the affinities order: 1>2≈3. Three complexes exhibit oxidative cleavage of pBR322 plasmid DNA including a reliance on H2O2 as the activator. Compound 1 demonstrates an increased DNA cleavage activity as compared with 2 and 3, which could degrade super coiled DNA (SC DNA) into nicked coiled DNA (NC DNA) in lower concentration (5 µM). Moreover, all compounds could quench the intrinsic fluorescence of bovine serum albumin (BSA) in a static quenching process. Complex 1 also shows higher anticancer activity than cisplatin with lower IC50 value of incubation for both 24 h and 48 h.


Assuntos
Cobalto/química , Quinolinas/química , Animais , Bovinos , Cristalografia por Raios X , DNA/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Ligantes , Magnetismo , Polímeros/química , Ligação Proteica , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade
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