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1.
Inorg Chem ; 60(11): 7937-7951, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34015217

RESUMO

On the basis of the lanthanide metalloligand [Ln(ODA)3]3- (H2ODA = oxydiacetic acid), three new Na-Ln heterometallic coordination polymers, [Ln(ODA)3Na2]n [Ln = Eu (1) and Gd (2)] and [Tb(ODA)3Na3(H2O)2]n (3), had been assembled by adjusting the concentration of Na+ ions in the reaction system. The investigations of fluorescence sensing showed that 1 could be a ratiometric probe to detect tetracycline (TC) and oxytetracycline (OTC) with high sensitivity and low detection limits, 71.92 ppb for the former and 45.54 ppb for the latter, and 3 could selectively sense 4-(phenylazo)aniline through the turn-off pathway with 14.59 ppb of detection limits. Moreover, the competing and circulating experiments indicated that both 1 and 3 had satisfactory antiinterference and recyclability for the corresponding analytes. All of these results implied that 1 and 3 should be potential fluorescent sensors for the detection of TC/OTC and 4-(phenylazo)aniline, and the possible sensing mechanism had also been discussed in depth.


Assuntos
Compostos de Anilina/análise , Antibacterianos/análise , Complexos de Coordenação/química , Elementos da Série dos Lantanídeos/química , Polímeros/química , Sódio/química , Tetraciclina/análise , Complexos de Coordenação/síntese química , Modelos Moleculares , Estrutura Molecular
2.
Inorg Chem ; 56(12): 7145-7150, 2017 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-28581288

RESUMO

A novel pillar-layer porous lanthanide metal-organic framework [Tb3(ODA)3(BPDC)3Na2]n·Gx (UTSA-222, G = guest molecules) was constructed from an organic ligand [1,1'-biphenyl]-4,4'-dicarboxylate (BPDC2-) and a lanthanide metalloligand [Tb(ODA)]+ (H2ODA = oxydiacetic acid). The UTSA-222 contains two-dimensional intersecting channels with the Brunauer-Emmett-Teller surface area and pore volume of 703 m2 g-1 and 0.344 cm3 g-1, respectively, for the activated sample. It shows moderately high adsorption selectivity for C2H2/CO2 and C2H2/CH4 separations at 1 atm and room temperature.

3.
Inorg Chem ; 53(12): 5922-30, 2014 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-24884167

RESUMO

On the basis of lanthanide metalloligands, [Ln(ODA)3](3-) (H2ODA = oxydiacetic acid), three series of d-f heterometallic metal-organic frameworks, {[Co(H2O)6]·[Ln2(ODA)6Co2]·6H2O}n [1; Ln = Gd (1a), Dy (1b), and Er (1c)], {[Ln2(ODA)6Cd3(H2O)6]·mH2O}n [2; Ln = Pr (2a), Nd (2b), Sm (2c), Eu (2d), and Dy (2e), m = 9, 6, or 3], and {[Cd(H2O)6]·[Ln2(ODA)6Cd2]·mH2O}n [3; Ln = Dy (3a), Ho (3b), Er (3c), Tm (3d), and Lu (3e), m = 6 or 12], were designed and synthesized by a solvent volatilization and hydrothermal method. Magnetic investigation of 1 reveals the ferromagnetic interactions between the metal ions. In 2, Ln(III) ions occupied the inversion centers, which are confirmed by the fact that the emission intensity ratio of (5)D0 → (7)F1 to (5)D0 → (7)F2 of the Eu(III) ion is much more than 3 in 2d. It is worth noting that, in 2d, the intensity ratio I((5)D0→(7)F1)/I((5)D0→(7)F2) could decrease significantly upon the introduction of different hydrophilic guest molecules, which implies that the luminescent properties of 2d have a strong dependence on the geometry of the first coordination sphere of the Eu(III) ion.

4.
Adv Sci (Weinh) ; : e2403539, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923305

RESUMO

A stable crystalline organic porous salt (CPOSs-NXU-1) with 1D apertures has been assembled by the solvothermal method, which shows high-sensitivity "turn-on" fluorescence detection and large-capacity adsorption of As(III) ions in water. The detection limits, saturated adsorption capacity, and removal rate of CPOSs-NXU-1 for As(III) ions in an aqueous solution can reach 74.34 nm (5.57 ppb), 451.01 mg g-1, and 99.6%, respectively, at pH = 7 and room temperature. With the aid of XPS, IR, Raman, and DFT theoretical calculations, it is determined that CPOSs-NXU-1 adsorbed As(III) ions in the form of H2AsO3 - and H3AsO3 through hydrogen bonding between the host and guest. The mechanism for fluorescence sensitization of As(III) ions to CPOSs-NXU-1 is mainly to increase the energy level difference between the ground state and excited state investigated by UV-vis absorption spectra, UV-vis diffuse reflectance spectra, and theoretical calculations. By constructing fluorescent CPOSs, an integrated solution has been achieved to treating As(III) contamination in the water that is equipped with detection and removal. These results blaze a promising path for addressing trivalent arsenic contamination in water efficiently, rapidly, and economically.

5.
Chin J Integr Med ; 30(3): 213-221, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37688744

RESUMO

OBJECTIVE: To investigate the effect and possible mechanism of hydroxysafflor yellow A (HSYA) on human immortalized keratinocyte cell proliferation and migration. METHODS: HaCaT cells were treated with HSYA. Cell proliferation was detected by the cell counting kit-8 assay, and cell migration was measured using wound healing assay and Transwell migration assay. The mRNA and protein expression levels of heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF), EGF receptor (EGFR), phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), mammalian target of rapamycin (mTOR), and hypoxia-inducible factor-1α (HIF-1α) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. Circ_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with HSYA. The expression of circ_0084443 was detected by qRT-PCR. RESULTS: HSYA (800 µmol/L) significantly promoted HaCaT cell proliferation and migration (P<0.05 or P<0.01). It also increased the mRNA and protein expression levels of HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α, and increased the phosphorylation levels of PI3K and AKT (P<0.05 or P<0.01). Furthermore, HSYA promoted HaCaT cell proliferation and migration via the HBEGF/EGFR and PI3K/AKT/mTOR signaling pathways (P<0.01). Circ_0084443 attenuated the mRNA expression levels of HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α (P<0.05). HSYA inhibited the circ_0084443 expression, further antagonized the inhibition of circ_0084443 on HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α, and promoted the proliferation of circ_0084443-overexpressing HaCaT cells (P<0.05 or P<0.01). However, HSYA could not influence the inhibitory effect of circ_0084443 on HaCaT cell migration (P>0.05). CONCLUSION: HSYA played an accelerative role in HaCaT cell proliferation and migration, which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways, and had a particular inhibitory effect on the keratinocyte negative regulator circ_0084443.


Assuntos
Chalcona/análogos & derivados , Fosfatidilinositol 3-Quinase , Proteínas Proto-Oncogênicas c-akt , Quinonas , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptores ErbB/genética , Serina-Treonina Quinases TOR/metabolismo , Proliferação de Células , RNA Mensageiro/genética , Movimento Celular , Linhagem Celular Tumoral
6.
Chemistry ; 19(11): 3590-5, 2013 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-23417845

RESUMO

Framework-isomeric three-dimensional (3D) Cd-Ln heterometallic metal-organic frameworks (HMOFs), {[Ln2 (ODA)6 Cd3 (H2 O)6 ]⋅6 H2 O}n (Ln=Gd (1 a) and Tb (1 b), ODA=oxydiacetic acid) and {[Cd(H2 O)6 ]⋅[Ln2 (ODA)6 Cd2 ]⋅H2 O}n (Ln=Gd (2 a), Tb (2 b)), with neutral and anionic pores, respectively, were designed based on a lanthanide metalloligand strategy and synthesized by using a stepwise assembly and a hydrothermal method. Luminescence studies revealed that 1 b and 2 b can act as luminescent metal-organic frameworks and their light-emitting properties can be modulated by small guest molecules and the manganese counterion, respectively.


Assuntos
Cádmio/química , Elementos da Série dos Lantanídeos/química , Luminescência , Compostos Organometálicos/síntese química , Ânions/química , Cristalografia por Raios X , Medições Luminescentes , Modelos Moleculares , Compostos Organometálicos/química , Estereoisomerismo
7.
Neuropathology ; 33(1): 7-16, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22537175

RESUMO

Medulloblastoma is a primitive neuroectodermal tumor, which originates in the cerebellum, presumably due to the alterations of some neurogenetic elements. Sirtuin 1 (SIRT1), a class III histone deacetylase (HDAC), regulates differentiation of neuronal stem cells but its status in medulloblastomas remains largely unknown. The current study aimed to address this issue by checking SIRT1 expression in noncancerous cerebellar tissues, medulloblastoma tissues and established cell lines. The roles of SIRT1 in proliferation and survival of UW228-3 medulloblastoma cells were analyzed by SIRT1 small interfering RNA (siRNA) transfection and SIRT1 inhibitor nicotinamide treatment. The results revealed that the frequency of SIRT1 expression in medulloblastoma tissues was 64.17% (77/120), while only one out of seven tumor-surrounding noncancerous cerebellar tissues showed restricted SIRT1 expression in the cells within the granule layer. Of the three morphological subtypes, the rates of SIRT1 detection in the large cell/anaplastic cell (79.07%; 34/43) and the classic medulloblastomas (60.29%; 41/68) are higher than that (22.22%; 2/9) in nodular/desmoplastic medulloblastomas (P<0.01 and P<0.05, respectively). Heterogeneous SIRT1 expression was commonly observed in classic medulloblastoma. Inhibition of SIRT1 expression by siRNA arrested 64.96% of UW228-3 medulloblastoma cells in the gap 1 (G1) phase and induced 14.53% of cells to apoptosis at the 48-h time point. Similarly, inhibition of SIRT1 enzymatic activity with nicotinamide brought about G1 arrest and apoptosis in a dose-related fashion. Our data thus indicate: (i) that SIRT1 may act as a G1-phase promoter and a survival factor in medulloblastoma cells; and (ii) that SIRT1 expression is correlated with the formation and prognosis of human medulloblastomas. In this context, SIRT1 would be a potential therapeutic target of medulloblastomas.


Assuntos
Ciclo Celular/genética , Neoplasias Cerebelares/genética , Cerebelo/metabolismo , Meduloblastoma/genética , Sirtuína 1/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Cerebelo/efeitos dos fármacos , Cerebelo/patologia , Humanos , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Niacinamida/farmacologia , Sirtuína 1/metabolismo
8.
Medicine (Baltimore) ; 99(25): e20538, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32569174

RESUMO

OBJECTIVE: We undertook a meta-analysis to compare the efficacy and safety of single versus double door posterior cervical laminoplasty for cervical spondylotic myelopathy. METHODS: PubMed, Embase, and Cochrane Central Register of controlled trials were searched for randomized controlled trials investigating single and double door posterior cervical laminoplasty for cervical spondylotic myelopathy. The Mantel-Haenszel method with the fixed-effects or random-effects model was used to calculate relative risks and 95% confidence intervals (CIs). RESULTS: Seven studies with 224 patients met the eligibility criteria and were included. There was a significant difference in Japanese Orthopedic Association score (MD = 0.79, 95%CI [0.09, 1.49], P = .03; P for heterogeneity = .09, I = 45%), and adverse events (OR = 0.32, 95%CI [0.11, 0.95], P = .04; P for heterogeneity = 1.00, I = 0%) between the double door posterior cervical laminoplasty group and the single door posterior cervical laminoplasty group. There was no significance in operative time (MD = 0.56, 95%CI [-11.86, 12.98], P = .93; P for heterogeneity = 0.001, I = 73%) and length of hospital stay (OR = -0.75, 95%CI [-1.78, 0.27], P = .15; P for heterogeneity = 1.00, I = 0%) between the 2 groups. CONCLUSION: Double door posterior cervical laminoplasty is more effective and safer than single door laminoplasty in the treatment of cervical spondylotic myelopathy.


Assuntos
Vértebras Cervicais/cirurgia , Laminoplastia/métodos , Espondilose/cirurgia , Adulto , Idoso , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
9.
Inorg Chem ; 48(14): 6326-8, 2009 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-19534547

RESUMO

A novel 3D heteropolymetallic coordination polymer, {[Na(5)Cu(8)Sm(4)(NTA)(8)(ClO(4))(8)(H(2)O)(22)] x ClO(4) x 8 H(2)O}(n) (H(3)NTA = nitrilotriacetic acid), based on the metalloligand [Cu(NTA)](-), has been prepared and characterized by X-ray crystal diffraction. The single-crystal structure shows that the complex forms a 3D framework with interpenetrating 1D channels along the a and b axes, respectively. These channels construct 2D "tube net" layers in the ab plane. The temperature-dependent magnetic properties have been studied and showed the presence of antiferromagnetic couplings between Cu(II) ions. The investigation of ion exchange reveals that the uncoordinated perchlorate anions that filled in the channels can be exchanged by anions of tetrafluoroborate.

10.
Cancer Lett ; 240(2): 253-60, 2006 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-16337337

RESUMO

The frequency of cancer-associated m2m2- (C-) genotype of CYP1A1 and the factors contributing to the increased CYP1A1 expression in gastric cancers (GCs) are largely unknown. To address theses issues, PCR-restriction fragment length polymorphism (PCR-RFLP) was performed to elucidate the MspI polymorphism in 60 GC cases and 57 normal donor samples. The frequencies of m1m1-, m1m2- and m2m2-genotype were 43.3, 45 and 11.7% among GC patients and 45.6, 49.1 and 5.3% among the normal donors respectively, demonstrating no significant difference of them between cancer and control groups (chi(2)=0.343, P=0.558). The correlation of Aryl hydrocarbon receptor (AhR) with the frequent CYP1A1 expression in stepwise gastrocarcinogenesis was determined by RT-PCR, immunohistochemical staining (IHC) and Western blotting, using GC samples as well as their pre-malignant and non-cancerous counterparts. RT-PCR revealed that the AhR detection rates were 100, 94.12 and 85.17% in GC, pre-malignant and non-cancerous mucosa (P>0.05) respectively but the level of AhR expression in GCs was much higher than that of non-cancerous tissues. IHC showed that the frequencies of AhR detection were 94.87% (37/39) in GCs, 94.12% (16/17) in pre-malignant lesions and 50% (3/6) in non-cancerous mucosa, revealing significant difference in frequencies of AhR detection and levels of AhR expression between GC or pre-malignant group and non-cancerous one (P<0.05). The frequency of AhR nucleus translocation was significantly high in GCs (94.87%; 37/39) than that in pre-malignant (70.59%; 12/17) and especially in non-cancerous group (16.67%; 1/6). Co-existence of AhR nuclear translocation and CYP1A1 expressions were found in 82.70% (43/52) of GCs (r(s)=0.437, P<0.01). Our results suggest (1) that CYP1A1 MspI polymorphism may not contribute to the high gastric cancer risk in Dalian region and (2) that enhanced AhR expression and especially its nuclear translocation may be a favorable factor for GC formation presumably via up-regulating CYP1A1 expression.


Assuntos
Citocromo P-450 CYP1A1/genética , Desoxirribonuclease HpaII/metabolismo , Polimorfismo Genético , Lesões Pré-Cancerosas/genética , Receptores de Hidrocarboneto Arílico/genética , Neoplasias Gástricas/genética , Estudos de Casos e Controles , Núcleo Celular/metabolismo , China/epidemiologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Regulação Neoplásica da Expressão Gênica , Genótipo , Humanos , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/patologia , Transporte Proteico , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/patologia , Transcrição Gênica
11.
Neurosci Lett ; 384(1-2): 33-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15893423

RESUMO

Resveratrol induces apoptosis and regulates CYP1A1 and CYP1B1 expression in human medulloblastoma cells. To elucidate the potential correlation of their expressions with the anti-medulloblastoma effects of resveratrol, human medulloblastoma cells, UW228-3, were treated with CYP1A1 selective inhibitor (alpha-naphthoflavone, alpha-NF), selective CYP1A1/1A2 inducer (beta-naphthoflavone, beta-NF) and their combination with resveratrol, respectively. The influences of those treatments on the expressions of CYP1A1, 1A2 and 1B1 as well as the cell growth, differentiation and death were analyzed. It was found that neither alpha-NF nor beta-NF had any effect on cell growth. alpha-NF inhibited resveratrol-induced CYP1A1 expression without interfering cell differentiation and apoptosis. beta-NF could up-regulate resveratrol-induced CYP1A1 expression but not enhance the anti-cancer effects of resveratrol. CYP1A2 was undetectable in the cells irrespective to the treatments. Aryl hydrocarbon receptor (AhR) was absent in UW228-3 cells under normal culture and treated with resveratrol but induced by both alpha- and beta-NF. Immunohistochemical examination performed on 11 pairs of human medulloblastoma and noncancerous cerebellar tissues revealed that AhR was undetectable in either of them, whereas CYP1A1 was expressed in cerebellum but down-regulated or diminished in their malignant counterparts. Our data suggest for the first time that CYP1A1 and 1B1 expressions in human medulloblastoma cells are AhR-independent and have no direct links with resveratrol-induced differentiation and apoptosis. Appearance of CYP1A1 expression may reflect a more maturated status and a better prognosis of medulloblastomas.


Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Estilbenos/farmacologia , Apoptose/efeitos dos fármacos , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Encéfalo/citologia , Encéfalo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP1A1/antagonistas & inibidores , Citocromo P-450 CYP1B1 , Combinação de Medicamentos , Interações Medicamentosas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Imuno-Histoquímica/métodos , Meduloblastoma , Resveratrol , Sinaptofisina/metabolismo
12.
Oncol Rep ; 12(6): 1335-40, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15547760

RESUMO

CYP1A1 expression in various tissues of 43 gastric cancer cases was analyzed with frozen tissue array-based immunohistochemical staining (IHC), RT-PCR, Western blot analysis and EROD (7-ethoxyresourfin-O-deethylase) assay. CYP1A1 was detected immunohistochemically in 86% (37/43) of gastric cancers, in both 57% (4/7) of atrophic gastritis and intestinal metaplasia and in 7.7% (1/13) of non-cancerous mucosa. RT-PCR and Western blot analysis revealed coincident results with that of IHC and ruled out possible concurrent CYP1A2 expression. EROD assay showed increased CYP1A1/1B1 activity in either cancer or premalignant tissues but not in non-cancerous ones. The frequencies of CYP1A1 expression are significantly different between non-cancerous and premalignant (P<0.025) or cancer groups (P<0.005), suggesting that CYP1A1 is expressed at relatively early stage of gastrocarcinogenesis and exerts its effects throughout the stepwise oncogenic processes.


Assuntos
Biomarcadores Tumorais/análise , Citocromo P-450 CYP1A1/biossíntese , Lesões Pré-Cancerosas/metabolismo , Neoplasias Gástricas/metabolismo , Western Blotting , Feminino , Humanos , Imuno-Histoquímica , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Mol Oncol ; 6(1): 48-61, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22153617

RESUMO

Medulloblastoma cells exhibit varied responses to therapy by all-trans retinoic acid (RA). The underlying mechanism for such diverse effects however remains largely unclear. In this study, we attempted to elucidate the molecular basis of RA resistance through the study of RA signaling components in both RA-sensitive (Med-3) and RA-resistant (UW228-2 and UW228-3) medulloblastoma cells. The results revealed that RARα/ß/γ and RXRα/ß/γ were found in the three cell lines. Expression of CRABP-I and CRABP-II was seen in Med-3 cells, up-regulated when treated with RA, but was absent in UW228-2 and UW228-3 cells regardless of RA treatment. Bisulfite sequencing revealed 8 methylated CG sites at the promoter region of CRABP-II in UW228-2 and UW228-3 but not in Med-3 cells. Demethylation by 5-aza-2'-deoxycytidine recovered CRABP-II expression. Upon restoration of CRABP-II expression, both UW228-2 and UW228-3 cells responded to RA treatment by forming neuronal-like differentiation, synaptophysin expression, ß-III tubulin upregulation, and apoptosis. Furthermore, CRABP-II specific siRNA reduced RA sensitivity in Med-3 cells. Tissue microarray-based immunohistochemical staining showed variable CRABP-II expression patterns among 104 medulloblastoma cases, ranging from negative (42.3%), partly positive (14.4%) to positive (43.3%). CRABP-II expression was positively correlated with synaptophysin (rs = 0.317; p = 0.001) but not with CRABP-I expression (p > 0.05). In conclusion, aberrant methylation in CRABP-II reduces the expression of CRABP-II that in turn confers RA resistance in medulloblastoma cells. Determination of CRABP-II expression or methylation status may enable a personalized RA therapy in patients with medulloblastomas and other types of cancers.


Assuntos
Metilação de DNA/efeitos dos fármacos , Meduloblastoma/metabolismo , Receptores do Ácido Retinoico/metabolismo , Tretinoína/farmacologia , Azacitidina/farmacologia , Sequência de Bases , Linhagem Celular Tumoral , Sistema Enzimático do Citocromo P-450 , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Meduloblastoma/genética , Meduloblastoma/patologia , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , RNA Interferente Pequeno/metabolismo , Receptores do Ácido Retinoico/genética , Ácido Retinoico 4 Hidroxilase , Análise de Sequência de DNA , Transdução de Sinais/efeitos dos fármacos , Análise Serial de Tecidos , Transfecção
14.
Biochem Pharmacol ; 79(10): 1516-25, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20105429

RESUMO

Cancer preventive reagent trans-resveratrol is intracellularly biotransformed to different metabolites. However, it is still unclear whether trans-resveratrol exerts its biological effects directly or through its metabolite(s). This issue was addressed here by identifying the metabolic pattern and the bioactive form of resveratrol in a resveratrol-sensitive human medulloblastoma cell line, UW228-3. The cell lysates and condition media of UW228-3 cells with or without 100 microM resveratrol treatment were analyzed by HPLC and LC/MS which revealed (1) that resveratrol was chemically unstable and the spontaneous generation of cis-resveratrol reduced resveratrol's anti-medulloblastoma efficacy and (2) that resveratrol monosulfate was the major metabolite of the cells. To identify the bioactive form of resveratrol, a mixture-containing approximately half fraction of resveratrol monosulfate was prepared by incubating trans-resveratrol with freshly prepared rat brain lysates. Medulloblastoma cells treated by 100 microM of this mixture showed attenuated cell crisis. The overall levels of the three brain-associated sulfotransferases (SULT1A1, 1C2 and 4A1) were low in medulloblastoma cells in vivo and in vitro in comparison with that in human noncancerous and rat normal cerebella; resveratrol could more or less up-regulate the production of these enzymes in UW228-3 cells but their overall level was still lower than that in normal cerebellum tissue. Our study thus demonstrated for the first time that trans-resveratrol is the bioactive form in medulloblastoma cells in which the expression of brain-associated SULTs was down-regulated, resulting in the increased intracellular bioavailability and anti-medulloblastoma efficacy of trans-resveratrol.


Assuntos
Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Neoplasias Cerebelares/tratamento farmacológico , Meduloblastoma/tratamento farmacológico , Estilbenos/farmacocinética , Adolescente , Animais , Biotransformação , Western Blotting , Linhagem Celular Tumoral , Criança , Cromatografia Líquida de Alta Pressão , Humanos , Ratos , Resveratrol , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estilbenos/farmacologia , Sulfotransferases/metabolismo , Adulto Jovem
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