RESUMO
Breast cancer is one of the leading causes of death in the female population because of the resistance of cancer cells to many anticancer drugs used. Curcumin has cytotoxic activities against breast cancer cells, although it has limited use due to its poor bioavailability and rapid metabolic elimination. The synthesis of metal complexes of curcumin and curcuminoids is a relevant topic in the search for more active and selective derivatives of these molecular scaffolds. However, solubility and bioavailability are concomitant disadvantages of these types of molecules. To overcome such drawbacks, the preparation of inclusion complexes offers a chemical and pharmacologically safe option for improving the aqueous solubility of organic molecules. Herein, we describe the preparation of the inclusion complex of dimethoxycurcumin magnesium complex (DiMeOC-Mg, (4)) with beta-cyclodextrin (DiMeOC-Mg-BCD, (5)) in the stoichiometric relationship 1:1. This new inclusion complex's solubility in aqueous media phosphate buffer saline (PBS) was improved by a factor of 6x over the free metal complex (4). Furthermore, 5 affects cell metabolic rate, cell morphology, cell migration, induced apoptosis, and downregulation of the matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), and signal transducer and activator of transcription-3 (STAT3) expression levels on MD Anderson metastasis breast-231 cancer (MDA-MB-231) cell lines. Results of an antitumor assay in an in ovo model showed up to 30% inhibition of tumor growth for breast cancer (MDA-MB-231) when using (5) (0.650 mg/kg dose) and 17.29% inhibition with the free homoleptic metal complex (1.5 mg/kg dose, (4)). While the formulation of inclusion complexes from metal complexes of curcuminoids demonstrates its usefulness in improving the solubility and bioavailability of these metallodrugs, the new compound (5) exhibits excellent potential for use as a therapeutic agent in the battle against breast cancer.
Assuntos
Antineoplásicos , Curcumina , Curcumina/análogos & derivados , Magnésio , beta-Ciclodextrinas , beta-Ciclodextrinas/química , Curcumina/farmacologia , Curcumina/química , Curcumina/farmacocinética , Humanos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/química , Magnésio/química , Apoptose/efeitos dos fármacos , Feminino , Linhagem Celular Tumoral , Fator de Transcrição STAT3/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Movimento Celular/efeitos dos fármacos , Solubilidade , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Embrião de Galinha , Metaloproteinase 9 da Matriz/metabolismoRESUMO
The crystal structure determination of metal complexes of curcuminoids is a relevant topic to assess their unequivocal molecular structure. We report herein the first two X-ray crystal structures of homoleptic metal complexes of a curcuminoid, namely Dimethoxycurcumin (DiMeOC), with gallium and indium. Such successful achievement can be attributed to the suppression of interactions from the phenolic groups, which favor an appropriate molecular setup, rendering Dimethoxycurcumin gallium ((DiMeOC)2-Ga) and Dimethoxycurcumin indium ((DiMeOC)3-In) crystals. Surprisingly, the conformation of ligands in the crystal structures shows differences in each metal complex. Thus, the ligands in the (DiMeOC)2-Ga complex show two different conformers in the two molecules of the asymmetric unit. However, the ligands in the (DiMeOC)3-In complex exhibit three different conformations within the same molecule of the asymmetric unit, constituting the first such case described for an ML3 complex. The cytotoxic activity of the (DiMeOC)2-Ga complex is 4-fold higher than cisplatin against the K562 cell line and has comparable activity towards U251 and PC-3 cell lines. Interestingly, this complex exhibit three times lesser toxicity than cisplatin and even slightly lesser cytotoxicity than curcumin itself.
Assuntos
Antineoplásicos , Complexos de Coordenação , Gálio , Gálio/farmacologia , Gálio/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Cisplatino , Índio/química , Diarileptanoides , Linhagem Celular Tumoral , Ligantes , Antineoplásicos/farmacologiaRESUMO
The first single crystal structure of the homoleptic copper (II) ML2 complex (M=Cu (II), L = curcumin) was obtained and its structure was elucidated by X-ray diffraction showing a square planar geometry, also confirmed by EPR. The supramolecular arrangement is supported by C-H···O interactions and the solvent (MeOH) plays an important role in stabilizing the crystal packing Crystallinity was additionally assessed by XRD patterns. The log P value of the complex (2.3 ± 0.15) was determined showing the improvement in water solubility. The cytotoxic activity of the complex against six cancer cell lines substantially surpasses that of curcumin itself, and it is particularly selective against leukemia (K562) and human glioblastoma (U251) cell lines, with similar antioxidant activity to BHT. This constitutes the first crystal structure of pristine curcumin complexed with a metal ion.
RESUMO
To our previously reported first crystal structure of a homoleptic zinc curcuminoid complex with square pyramidal geometry, we add herein three new geometries of homoleptic type complexes i.e. octahedral, trigonal-pyramidal, and trigonal-bipyramidal. Octahedral geometry was observed in the new pseudo-polymorph of the DAC-Zn complex resulting from crystallization in DMF, while square-pyramidal geometry was obtained in DMSO. Improving crystallinity involved suppressing the phenolic interactions by etherification and esterification. The complete characterization of these complexes was carried out using SCXRD, IR, MS, EA, liquid, and solid-state NMR. Moreover, the cytotoxic activity of all complexes was evaluated. The IC50 values for the DiMeOC-Zn (7) complex were 8 or 22 times higher than for cisplatin in the U251 and HCT-15 cell lines, indicating a high antiproliferative and therapeutic potential.
RESUMO
We report herein the synthesis and characterization of three heterocyclic curcuminoid ligands and their homoleptic metal complexes with magnesium and copper. Thus, N-methyl-2-pyrrolecarboxaldehyde, Furan-2-carboxaldehyde, and 2-Thiophenecarboxaldehyde were condensed with 2,4-pentanedione-boron trioxide complex. The first N-methyl-2-pyrrole curcuminoid and its Mg(II) complex are reported. All curcuminoid ligands and their corresponding metal complexes were characterized by infrared spectroscopy (IR), liquid state nuclear magnetic resonance (LSNMR), electron paramagnetic resonance (EPR), mass spectrometry (MS) and single crystal X-ray diffraction (SCXRD). The ThiopheneCurc-Cu (9) constitutes the first case of a "conformationally-heteroleptic" complex. The unique six-peaks star arrangement for the ThiopheneCurc ligand derived from the supramolecular description is reported. The metal complexes of FuranCurc-Mg (5) and ThiopheneCurc-Cu (9) have a good antioxidant effect (IC50 = 11.26 ± 1.73 and 10.30 ± 0.59 µM), three and two times higher than their free ligands respectively. Additionally, (5) shows remarkable cytotoxicity against colon cancer adenocarcinoma cell line HCT-15, comparable to that of cisplatin, with a negligible toxic effect in vitro towards a healthy monkey kidney cell line (COS-7).
Assuntos
Antineoplásicos , Complexos de Coordenação , Diarileptanoides , Complexos de Coordenação/química , Cisplatino , Antioxidantes/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Cobre/química , Cristalografia por Raios X , Ligantes , Antineoplásicos/químicaRESUMO
Fluorination of pharmaceutical agents has afforded crucial modifications to their pharmacological profiles, leading to important advances in medicinal chemistry. On the other hand, metallodrugs are considered to be valuable candidates in the treatment of several diseases, albeit with the caveat that they may exhibit pharmacological disadvantages, such as poor water solubility, low bioavailability and short circulating time. To surmount these limitations, two approaches have been developed: one based on the design of novel metallodrug-delivering carriers and the other based on optimizing the structure of the ligands bound to the metal center. In this context, fluorination of the ligands may bring beneficial changes (physicochemical and biological) that can help to elude the aforementioned drawbacks. Thus, in this review, we discuss the use of fluorinated ligands in the design of metallodrugs that may exhibit potential anticancer activity.
RESUMO
The worldwide known and employed spice of Asian origin, turmeric, receives significant attention due to its numerous purported medicinal properties. Herein, we report an optimized synthesis of curcumin and symmetric curcuminoids of aromatic (bisdemethoxycurcumin) and heterocyclic type, with yields going from good to excellent using the cyclic difluoro-boronate derivative of acetylacetone prepared by reaction of 2,4-pentanedione with boron trifluoride in THF (ca. 95%). The subsequent cleavage of the BF2 group is of significant importance for achieving a high overall yield in this two-step procedure. Such cleavage occurs by treatment with hydrated alumina (Al2O3) or silica (SiO2) oxides, thus allowing the target heptanoids obtained in high yields as an amorphous powder to be filtered off directly from the reaction media. Furthermore, crystallization instead of chromatographic procedures provides a straightforward purification step. The ease and efficiency with which the present methodology can be applied to synthesizing the title compounds earns the terms "click" and "unclick" applied to describe particularly straightforward, efficient reactions. Furthermore, the methodology offers a simple, versatile, fast, and economical synthetic alternative for the obtention of curcumin (85% yield), bis-demethoxycurcumin (78% yield), and the symmetrical heterocyclic curcuminoids (80-92% yield), in pure form and excellent yields.
Assuntos
Curcumina , Curcumina/química , Diarileptanoides , Dióxido de Silício , Curcuma/química , Extratos Vegetais/químicaRESUMO
Dehydroleucodine is a bioactive sesquiterpene lactone. Herein, four dehydroleucodine amino derivatives were synthesized using the amines proline, piperidine, morpholine, and tyramine, and spectroscopic methods and single-crystal X-ray diffraction unambiguously established their structures. The cytotoxic activity of these compounds was evaluated against eight acute myeloid leukemia cell lines, and their toxicity to peripheral blood mononuclear cells was also determined. The proline adduct was the most active compound, it showed anti-leukemic activity, upregulated heme oxygenase 1 (HMOX1) and the primary stress-inducible isoform of the heath shock 70 kDa protein 1 (HSPA1A), and downregulated NFkB1 transcription, it was also found to be about 270 times more water soluble than dehydroleucodine.
Assuntos
Proliferação de Células/efeitos dos fármacos , Lactonas/química , Leucemia Mieloide Aguda/tratamento farmacológico , Leucócitos Mononucleares/efeitos dos fármacos , Sesquiterpenos/química , Linhagem Celular Tumoral , Cristalografia por Raios X , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/genética , Heme Oxigenase-1/genética , Humanos , Lactonas/síntese química , Lactonas/farmacologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Morfolinas/química , Subunidade p50 de NF-kappa B/genética , Piperidinas/química , Sesquiterpenos/síntese química , Sesquiterpenos/farmacologia , Tiramina/químicaRESUMO
Curcumin, the most important secondary metabolite isolated from Curcuma longa, is known for its numerous purported therapeutic properties and as a natural dye. Herein, based on curcumin's intrinsic fluorescence, a search for improved curcumin-based fluorophores was conducted. Within the set of semi-synthetic curcumin derivatives i.e. mono (1), di (2), tri (3), tetra (4) benzylated and dibenzyl-fluoroborate (5), the fluorescence properties of 2 and 5 in solution outstood with a two-fold quantum yield compared to curcumin. Furthermore, all benzylated derivatives showed a favorable minimal cytotoxic activity upon screening at 25 µM against human cancer and non-tumoral COS-7 cell lines, with a reduction of its cytotoxic effect related to the degree of substitution. Fluorophores 2 and 5 are versatile bioimaging tools, as revealed by Confocal Fluorescence Microscopy (CFM), and showed permeation of living cell membranes of astrocytes and astrocytomas. When 2 is excited with a 405- (blue) or 543-nm (green) laser, it is possible to exclusively and intensively visualize the nucleus. However, the fluorescence emission fades as the laser wavelength moves towards the red region. In comparison, 5 allows selective visualization of cytoplasm when a 560-nm laser is used, showing emission in the NIR region, while it is possible to exclusively observe the nucleus at the blue region with a 405-nm laser.
Assuntos
Núcleo Celular , Citoplasma , Diarileptanoides/química , Diarileptanoides/farmacologia , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Imagem Molecular , Núcleo Celular/metabolismo , Curcumina/química , Curcumina/farmacologia , Citoplasma/metabolismo , Modelos Moleculares , Conformação Molecular , Imagem Molecular/métodos , Estrutura MolecularRESUMO
The present study aims to evaluate the antiarthritic activity of diacetylcurcumin (DAC), a synthetic derivative where the free phenolic groups of curcumin are derivatized by acetylation, thereby conferring greater lipophilicity to the parent molecule and partially overcoming the limited systemic bioavailability of curcumin. Antiarthritic activity was evaluated on a Freund's complete adjuvant (FCA)-induced murine model of arthritis. Oral administration of DAC (60 and 120 mg/kg) resulted in a significant inhibition of inflammation in the acute and chronic phases, respectively, demonstrating an improved and sustained anti-inflammatory effect, comparable to that of curcumin (150 mg/kg) in the chronic stage at a lower dose. Phenylbutazone (80 mg/kg) was used as a reference drug. The pharmacological consequence of DAC or curcumin treatment is the prevention of secondary lesions commonly associated with this biological model.
Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Curcumina/análogos & derivados , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/etiologia , Artrite Experimental/patologia , Cromatografia Líquida de Alta Pressão , Curcumina/química , Curcumina/farmacologia , Modelos Animais de Doenças , Adjuvante de Freund/efeitos adversos , Espectroscopia de Ressonância Magnética , Camundongos , Ratos , Resultado do TratamentoRESUMO
At the present time, scientists place a great deal of effort worldwide trying to improve the therapeutic potential of metal complexes of curcumin and curcuminoids. Herein, the synthesis of four homoleptic metal complexes with diacetylcurcumin (DAC), using a ligand designed to prevent the interaction of phenolic groups, rendering metal complexes through the ß-diketone functionality, is reported. Due to their physiological relevance, we used bivalent magnesium, zinc, copper, and manganese for complexation with DAC. The resulting products were characterized by ultraviolet-visible (UV-Vis), fluorescence spectroscopy, infrared spectroscopy (IR), liquid and solid-state nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), magnetic moment, mass spectrometry (MS), single crystal, and powder X-ray diffraction (SCXRD and PXRD). Crystallization was achieved in dimethylsulfoxide (DMSO) or N,N-dimethylformamide (DMF) as triclinic systems with space group P-1, showing the metal bound to the ß-diketone function, while the 1H-NMR confirmed the preference of the enolic form of the ligand. Single crystal data demonstrated a 1:2 metal:ligand ratio. The inhibition of lipid peroxidation was evaluated using the thiobarbituric acid reactive substance assay (TBARS). All four metal complexes (Mg, Zn, Cu, and Mn) exhibited good antioxidant effect (IC50 = 2.03 ± 0.27, 1.58 ± 0.07, 1.58 ± 0.15 and 1.24 ± 0.10 µM respectively) compared with butylated hydroxytoluene (BHT) and α-tocopherol. The cytotoxic activity in human cancer cell lines against colon adenocarcinoma (HCT-15), mammary adenocarcinoma (MCF-7), and lung adenocarcinoma (SKLU-1) was found comparable ((DAC)2Mg), or ca. 2-fold higher ((DAC)2Zn) than cisplatin. The acute toxicity assays indicate class 5 toxicity, according to the Organization for Economic Co-operation and Development (OECD) guidelines at doses of 3 g/kg for all complexes. No mortality or changes in the behavior of animals in any of the treated groups was observed. A therapeutic potential can be envisaged from the relevant cytotoxic activity upon human cancer cell lines in vitro and the undetected in vivo acute toxicity of these compounds.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Complexos de Coordenação/farmacologia , Cobre/química , Curcumina/análogos & derivados , Magnésio/química , Manganês/química , Zinco/química , Animais , Antineoplásicos Fitogênicos/síntese química , Antioxidantes/síntese química , Hidroxitolueno Butilado/farmacologia , Cátions Bivalentes , Linhagem Celular Tumoral , Cisplatino/farmacologia , Complexos de Coordenação/síntese química , Cristalografia por Raios X , Curcumina/química , Células Epiteliais , Humanos , Concentração Inibidora 50 , Ligantes , Peroxidação de Lipídeos/efeitos dos fármacos , Células MCF-7 , Masculino , Camundongos , Modelos Moleculares , Testes de Toxicidade Aguda , alfa-Tocoferol/farmacologiaRESUMO
We report herein the synthesis and crystal structures of five new homoleptic copper complexes of curcuminoids. The scarcity of reports of homoleptic complex structures of curcuminoids is attributed to the lack of crystallinity of such derivatives, and therefore, their characterization by single crystal X-ray diffraction is rare. The ligand design suppressing the phenolic interaction by esterification or etherification has afforded a significant increase in the number of known crystal structures of homoleptic metal complexes of curcuminoids revealing more favorable crystallinity. The crystal structures of the present new copper complexes show four-fold coordination with a square planar geometry. Two polymorphs were found for DiBncOC-Cu when crystallized from DMF. The characterization of these new complexes was carried out using infrared radiation (IR), nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), and single crystal X-ray diffraction (SCXRD) and the antioxidant and cytotoxic activity of the obtained complexes was evaluated.
Assuntos
Complexos de Coordenação/química , Cobre/química , Animais , Antioxidantes/síntese química , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Relação Dose-Resposta a Droga , Ligantes , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Ratos , Análise EspectralRESUMO
Curcumin (1) and ten derivatives (2-11) were synthesized and evaluated as cytotoxic and antioxidant agents. The results of primary screening by Sulforhodamine B assay against five human cancer cell lines (U-251 MG, glioblastoma; PC-3, human prostatic; HCT-15, human colorectal; K562, human chronic myelogenous leukemia; and SKLU-1, non-small cell lung cancer) allowed us to calculate the half maximal inhibitory concentration (IC50) values for the more active compounds against HCT-15 and K562 cell lines. Compounds 2 and 10 were the most active against both cell lines and were more active than curcumin itself. Thiobarbituric acid reactive substances (TBARS) assay showed that 7 has potent activity; even stronger than curcumin, α-tocopherol, and quercetin.
Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antioxidantes/síntese química , Antioxidantes/farmacologia , Curcumina/síntese química , Curcumina/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Curcumina/análogos & derivados , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , RatosRESUMO
ABSTRACT This study assesses the anti-arthritic effect of the affinin-enriched (spilanthol, main alkamide) hexane extract from the roots of Heliopsis longipes (A. Gray) S.F. Blake, Asteraceae, on a Freund adjuvant-induced arthritis model in rodents. The extract was orally administered at a dose of 2, 6.6, or 20 mg/kg; a significant edema-inhibitory activity in the acute and chronic phases was observed with a dose of 2 and 20 mg/kg, respectively. The extract showed higher anti-inflammatory and anti-arthritic effects than the reference drug phenylbutazone (80 mg/kg). Moreover, the extract prevented the occurrence of secondary lesions associated to this pharmacological model.
RESUMO
Six new partially acylated resin glycosides were isolated from convolvulin of Ipomoea purga, Ipomoea stans, and Ipomoea murucoides (Convolvulaceae). The structures of compounds 1-6 were elucidated by a combination of NMR spectroscopy and mass spectrometry. The structure of jalapinoside B (1) consists of a hexasaccharide core bonded to an 11-hydroxytetradecanoic (convolvulinic) acid forming a macrolactone acylated by a 2-methylbutanoyl, a 3-hydroxy-2-methylbutanoyl, and a quamoclinic acid B units. Purginoic acid A (2) contains a hexasaccharide core bonded to a convolvulinic acid acylated by a 3-hydroxy-2-methylbutanoyl unit. Stansin A (4) is an ester-type heterodimer, and consists of two stansoic acid A (3) units, acylated by 2-methylbutanoic and 3-hydroxy-2-methylbutanoic acids. The site of lactonization was located at C-3 of Rhamnose, and the position for the ester linkage of the monomeric unit B on the macrolactone unit A was established as C-4 of the terminal rhamnose. Compounds 5 and 6 are glycosidic acids. Murucinic acid II (5) is composed of a pentasaccharide core bonded to an 11-hydroxyhexadecanoic (jalapinolic) acid, acylated by an acetyl unit. Stansinic acid I (6) is a tetrasaccharide core bonded to a jalapinolic acid, acylated by 2-methylbutanoyl and 3-hydroxy-2-methylbutanoyl units. Preliminary testing showed the cytotoxicity of compounds 1-6 toward OVCAR and UISO-SQC-1 cancer cell lines. In addition, compound 1 showed an antiproliferative activity on glioma C6 and RG2 tumor cell lines. Copyright © 2016 John Wiley & Sons, Ltd.
Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Glicosídeos/farmacologia , Ipomoea/química , Oligossacarídeos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glioma , Glicosídeos/química , Glicosídeos/isolamento & purificação , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Extratos Vegetais/química , Relação Estrutura-AtividadeRESUMO
The effect of the stereochemistry of the sulfur atom on 1 H chemical shifts of the diasteromeric pair of cyclic sulfites of 4-[methoxy(4-nitrophenyl)methyl]-5-phenyl-1,3,2-dioxathiolan-2-oxide was investigated. The complete 1 H and 13 C NMR spectral assignment was achieved by the use of one-dimensional and two-dimensional NMR techniques in combination with X-ray data. A correlation of experimental data with theoretical calculations of chemical shift tensors using density functional theory and topological theory of atoms in molecules was made. Copyright © 2016 John Wiley & Sons, Ltd.
RESUMO
Curcuma is a natural compound that has shown neuroprotective properties, and has been reported to prevent aging and improve memory. While the mechanism(s) underlying these effects are unclear, they may be related to increases in neural plasticity. Morphological changes have been reported in neuronal dendrites in the limbic system in animals and elderly humans with cognitive impairment. In this regard, there is a need to use alternative therapies that delay the onset of morphologies and behavioral characteristics of aging. Therefore, the objective of this study was to evaluate the effect of curcuma on cognitive processes and dendritic morphology of neurons in the prefrontal cortex (PFC), the CA1 and CA3 regions of the dorsal hippocampus, the dentate gyrus, and the basolateral amygdala (BLA) of aged rats. 18-month-old rats were administered curcuma (100 mg/kg) daily for 60 days. After treatment, recognition memory was assessed using the novel object recognition test. Curcuma-treated rats showed a significant increase in the exploration quotient. Dendritic morphology was assessed by Golgi-Cox staining and followed by Sholl analysis. Curcuma-treated rats showed a significant increase in dendritic spine density and dendritic length in pyramidal neurons of the PFC, the CA1 and CA3, and the BLA. The preservation of dendritic morphology was positively correlated with cognitive improvements. Our results suggest that curcuma induces modification of dendritic morphology in the aforementioned regions. These changes may explain how curcuma slows the aging process that has already begun in these animals, preventing deterioration in neuronal morphology of the limbic system and recognition memory.
Assuntos
Envelhecimento , Transtornos Cognitivos , Dendritos/efeitos dos fármacos , Sistema Límbico/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Curcuma , Sistema Límbico/patologia , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Curcumin and its derivatives have been extensively studied for their remarkable medicinal properties, and their chemical synthesis has been an important step in the optimization of well-controlled laboratory production. A family of new compounds that mimic the structure of curcumin and curcuminoids, here named retro-curcuminoids (7-14), was synthesized and characterized using 1D ¹H- and 13C-NMR, IR, and mass spectrometry; the X-ray structure of 7, 8, 9, 10, 12, 13, and 14 are reported here for the first time. The main structural feature of these compounds is the reverse linkage of the two aromatic moieties, where the acid chloride moiety is linked to the phenolic group while preserving α, ß-unsaturated ketone functionality. The cytotoxic screening of 7, 8, 9, and 10 at 50 and 10 µg/mL was carried out with human cancer cell lines K562, MCF-7, and SKLU-1. Lipid peroxidation on rat brain was also tested for compounds 7 and 10. Compounds 7, 8, and 10 showed relevant cytotoxic activity against these cancer cell lines, and 10 showed a protective effect against lipid peroxidation. The molecular resemblance to curcuminoids and analogs with ortho substituents suggests a potential source of useful bioactive compounds.
Assuntos
Antineoplásicos , Curcumina/análogos & derivados , Estirenos/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ácidos Cumáricos/química , Cristalografia por Raios X , Humanos , Células MCF-7 , Masculino , Ressonância Magnética Nuclear Biomolecular , Ratos , Ratos WistarRESUMO
The sesquiterpene lactones dehydroleucodine (1) and leucodine (2) were isolated from Gynoxys verrucosa, a species used in traditional medicine in southern Ecuador. The activity of these compounds was determined against eight acute myeloid leukemia (AML) cell lines and compared with their activity against normal peripheral blood mononuclear cells. Compound 1 showed cytotoxic activity against the tested cell lines, with LD50 values between 5.0 and 18.9 µM. Compound 2 was inactive against all of the tested cell lines, demonstrating that the exocyclic methylene in the lactone ring is required for cytotoxic activity. Importantly, compound 1 induced less toxicity to normal blood cells than to AML cell lines and was active against human AML cell samples from five patients, with an average LD50 of 9.4 µM. Mechanistic assays suggest that compound 1 has a similar mechanism of action to parthenolide (3). Although these compounds have significant structural differences, their lipophilic surface signatures show striking similarities.
Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Asteraceae/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Antineoplásicos/química , Western Blotting , Ensaios de Seleção de Medicamentos Antitumorais , Equador , Células HL-60 , Células HeLa , Humanos , Lactonas/química , Leucemia Mieloide Aguda/tratamento farmacológico , Leucócitos Mononucleares/efeitos dos fármacos , Medicina Tradicional , Estrutura Molecular , Sesquiterpenos/químicaRESUMO
The methanol-soluble extract from the root of Ipomoea tyrianthina was studied in order to isolate compounds with activity on the central nervous system and vasorelaxant effects. Chromatographic methods were used to isolate and purify seven new glycolipids (2-8). The structures of compounds 1-8 were elucidated by a combination of NMR spectroscopy and mass spectrometry. Tyrianthinoic acid (1) is a glycosidic acid composed of a linear pentasaccharide core bonded to a 11-hydroxyhexadecanoic acid. The structure of tyrianthinic acids III (2), IV (3), and V (4) consists of a partially acylated tyrianthinoic acid. Tyrianthinic acid VI (8) is a tetrasaccharide core bonded to a jalapinolic acid, acylated by a 2-methyl-3-hydroxybutanoic acid. Tyrianthins C (5), D (6), and E (7) are ester-type heterodimers of scammonic acid A with different acylating residues in the two monomeric units. The macrolactonization site was located at C-3 of the rhamnose unit. The position of the ester linkage for monomeric unit B on the macrocyclic unit A was established at C-4 of the terminal quinovose. Compounds 5-7 increased the sleeping time induced by pentobarbital and the release of gamma-aminobutyric acid in brain cortex. In addition, compounds 5-7 showed significant in vitro relaxant effects on aortic rat rings, in endothelium- and concentration-dependent manners.