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1.
Carbohydr Polym ; 224: 115140, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472853

RESUMO

A new source of pectin with a cytotoxic effect on glioblastoma cells is presented. A homogeneous GWP-FP-S fraction (Mw of 29,170 g mol-1) was obtained by fractionating the crude pectin extract (GW) from Campomanesia xanthocarpa pulp. According to the monosaccharide composition, the GWP-FP-S was composed of galacturonic acid (58.8%), arabinose (28.5%), galactose (11.3%) and rhamnose (1.1%), comprising 57.7% of homogalacturonans (HG) and 42.0% of type I rhamnogalacturonans (RG-I). These structures were characterized by chromatographic and spectroscopic methods; GW and GWP-FP-S fractions were evaluated by MTT and crystal violet assays for their cytotoxic effects. Both fractions induced cytotoxicity (15.55-37.65%) with concomitant increase in the cellular ROS levels in human glioblastoma cells at 25-400 µg mL-1, after 48 h of treatment, whereas no cytotoxicity was observed for normal NIH 3T3 cells. This is the first report of in vitro bioactivity and the first investigation of the antitumor potential of gabiroba pectins.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Glioblastoma/patologia , Pectinas/química , Pectinas/farmacologia , Pimenta/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Monossacarídeos/análise , Pectinas/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo
2.
Radiat Res ; 192(4): 422-430, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31390309

RESUMO

Photodynamic therapy (PDT) uses a combination of photosensitizers with visible light to generate reactive species and selectively kill tumor or unwanted tissue. Znln2S4 nanoparticles are widely implemented in photovoltaic device materials and photolysis water catalysts owing to their unique photoelectric properties. Whether Znln2S4 itself can be used as an effective dye in PDT is still unknown. To determine the effects and potential mechanism of Znln2S4PDT on HepG2 cell apoptosis, electron microscopic analysis was performed to monitor the apoptotic morphology of HepG2 cells upon exposure to Znln2S4-PDT. Flow cytometry was performed to measure the apoptosis rate and intracellular ROS production. Western blot and ELISA were performed to reveal the expression changes in Bax, caspase-3 and caspase-9. Data from this work suggested that cells exhibited the typical apoptotic morphology in response to Znln2S4-PDT, with high apoptotic rate. The intracellular ROS production after Znln2S4-PDT occurred in a dose-dependent manner. Moreover, Znln2S4-PDT augmented the expression levels of pro-apoptosis factors, especially, Bax, caspase-3 and caspase-9. Taken together, our novel findings, Znln2S4-PDT elicited HepG2 cell apoptosis, suggesting Znln2S4 as a promising photosensitizer candidate for cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Índio/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Compostos de Zinco/farmacologia , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo
3.
Artif Cells Nanomed Biotechnol ; 47(1): 3548-3558, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31456420

RESUMO

The extensive relevance of nanoparticles arouses the requirement for manufacturing although the predictable technique are frequently perilous and energy saving. In the current study, zinc oxide nanoparticles manufactured from Allium cepa avert UVB radiation interceded irritation in human epidermal keratinocytes (HaCaT cells). In the current study, the zinc oxide nanoparticles (ZnO-NPs) was synthesized from the extract of A. cepa. The optimized ZnO-NPs hence attained and was enumerated and exemplified by UV visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscope (SEM) and EDAX impending analysis. In addition, amalgamated ZnO-NPs were experienced for cell viability (MTT), formation of reactive oxygen species (ROS), apoptosis, and antioxidant and lipid peroxidation (TBARS) levels. Also, we explored the effect of A. cepa ZnO-NPs in molecular level by evaluating the inflammatory and apoptotic markers, in which ZnO-NPs reinstated the interleukins 6, 10 and related signaling molecules like iNOS, COX-2 levels. Ultimately, ZnO-NPs induce apoptotic markers (Bax, Bcl-2) and also recommended that ZnO-NPs might aggravate cancer cell apoptosis in HaCaT cells.


Assuntos
Epiderme/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Cebolas/metabolismo , Raios Ultravioleta/efeitos adversos , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Animais , Linhagem Celular , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Queratinócitos/citologia , Queratinócitos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Protetores contra Radiação/química , Protetores contra Radiação/metabolismo , Protetores contra Radiação/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Óxido de Zinco/metabolismo
4.
Biosci Biotechnol Biochem ; 83(11): 2016-2026, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31272310

RESUMO

Exposure of PC12 cells to 10 mM glutamate caused significant viability loss, cell apoptosis, decreased activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) as well as increased levels of malondialdehyde (MDA). In parallel, glutamate significantly increased the intracellular levels of ROS and intracellular calcium. However, pretreatment of the cells with acteoside and isoacteoside significantly suppressed glutamate-induced cellular events. Moreover, acteoside and isoacteoside reduced the glutamate-induced increase of caspase-3 activity and also ameliorated the glutamate-induced Bcl-2/Bax ratio reduction in PC12 cells. Furthermore, acteoside and isoacteoside significantly inhibited glutamate-induced DNA damage. In the mouse model, acteoside significantly attenuated cognitive deficits in the Y maze test and attenuated neuronal damage of the hippocampal CA1 regions induced by glutamate. These data indicated that acteoside and isoacteoside play neuroprotective effects through anti-oxidative stress, anti-apoptosis, and maintenance of steady intracellular calcium.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Ácido Glutâmico/toxicidade , Glicosídeos/química , Glicosídeos/farmacologia , Neurotoxinas/toxicidade , Álcool Feniletílico/química , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Malondialdeído/metabolismo , Memória/efeitos dos fármacos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo
5.
Dalton Trans ; 48(30): 11469-11479, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31290881

RESUMO

Two rhodium complexes Rh1 and Rh2 with isoquinoline derivatives were synthesized and characterized. Both complexes displayed strong anticancer activity against various cancer cells and low cytotoxicity against non-cancer cells. These complexes triggered apoptosis via mitochondrial dysfunction that increased the levels of ROS and Ca2+ and released cytochrome C which ultimately activated caspases and the apoptosis pathway. The different biological activities of Rh1 and Rh2 could be associated with the presence of methoxy substituents on the ligands. In vivo studies showed that Rh1 effectively inhibited tumor growth in a T-24 xenograft mouse model with a less adverse effect than cisplatin. Overall, Rh1 and Rh2 induced apoptosis via mitochondrial pathways and could be developed as effective anticancer agents.


Assuntos
Antineoplásicos/química , Isoquinolinas/química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Ródio/química , Animais , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Transporte Biológico , Cálcio/metabolismo , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Modelos Moleculares , Conformação Molecular , Compostos Organometálicos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Int J Biol Macromol ; 137: 657-665, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31276719

RESUMO

To characterize the immuno-stimulating ingredient from the Korean citrus, Cheongkyool, a crude polysaccharide (CCE-0) was isolated from the pectinase digests of Cheongkyool peels, from which the complex polysaccharide CCE-I was purified to homogeneity by gel filtration. CCE-I highly enhanced the production of IL-6, TNF-α, and NO in RAW 264.7 cell lines. It augmented the mRNA expression of IL-6, TNF-α, and iNOS in a dose-dependent manner. Moreover, CCE-I dose-dependently induced phosphorylation of MAPKs and NF-κB related proteins and led to the nuclear translocation of p65. The effect of CCE-I on NO and IL-6 production was suppressed by treatment with specific antibodies for TLR2, TLR4, and scavenger receptors. Conversely, the primary structure of CCE-I that exhibited potent immunostimulatory activity was characterized by sugar composition, linkage analysis, and oligosaccharide analysis after ß-elimination. The results suggested that CCE-I may be a rhamnogalacturonan-I type, highly branched polysaccharide with short arabinan and galactan side chains.


Assuntos
Citrus/química , Ativação de Macrófagos/efeitos dos fármacos , Pectinas/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-6/genética , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Metilação , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Óxido Nítrico/metabolismo , Fosforilação/efeitos dos fármacos , Células RAW 264.7 , Fator de Necrose Tumoral alfa/genética
7.
IET Syst Biol ; 13(4): 169-179, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31318334

RESUMO

Developing a model for a signalling pathway requires several iterations of experimentation and model refinement to obtain an accurate model. However, the implementation of such an approach to model a signalling pathway induced by a poorly-known stimulus can become labour intensive because only limited information on the pathway is available beforehand to formulate an initial model. Therefore, a large number of iterations are required since the initial model is likely to be erroneous. In this work, a numerical scheme is proposed to construct a time-varying model for a signalling pathway induced by a poorly-known stimulus when its nominal model is available in the literature. Here, the nominal model refers to one that describes the signalling dynamics under a well-characterised stimulus. First, global sensitivity analysis is implemented on the nominal model to identify the most important parameters, which are assumed to be piecewise constants. Second, measurement data are clustered to determine temporal subdomains where the parameters take different values. Finally, a least-squares problem is solved to estimate the parameter values in each temporal subdomain. The effectiveness of this approach is illustrated by developing a time-varying model for NF-[inline-formula removed]B signalling dynamics induced by lipopolysaccharide in the presence of brefeldin A.


Assuntos
Brefeldina A/farmacologia , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Lipopolissacarídeos/farmacologia , Modelos Biológicos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Análise por Conglomerados , Interações de Medicamentos , Fatores de Tempo
8.
PLoS Biol ; 17(7): e3000376, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31318858

RESUMO

Apicomplexan parasites possess a plastid organelle called the apicoplast. Inhibitors that selectively target apicoplast housekeeping functions, including DNA replication and protein translation, are lethal for the parasite, and several (doxycycline, clindamycin, and azithromycin) are in clinical use as antimalarials. A major limitation of such drugs is that treated parasites only arrest one intraerythrocytic development cycle (approximately 48 hours) after treatment commences, a phenotype known as the 'delayed death' effect. The molecular basis of delayed death is a long-standing mystery in parasitology, and establishing the mechanism would aid rational clinical implementation of apicoplast-targeted drugs. Parasites undergoing delayed death transmit defective apicoplasts to their daughter cells and cannot produce the sole, blood-stage essential metabolic product of the apicoplast: the isoprenoid precursor isopentenyl-pyrophosphate. How the isoprenoid precursor depletion kills the parasite remains unknown. We investigated the requirements for the range of isoprenoids in the human malaria parasite Plasmodium falciparum and characterised the molecular and morphological phenotype of parasites experiencing delayed death. Metabolomic profiling reveals disruption of digestive vacuole function in the absence of apicoplast derived isoprenoids. Three-dimensional electron microscopy reveals digestive vacuole fragmentation and the accumulation of cytostomal invaginations, characteristics common in digestive vacuole disruption. We show that digestive vacuole disruption results from a defect in the trafficking of vesicles to the digestive vacuole. The loss of prenylation of vesicular trafficking proteins abrogates their membrane attachment and function and prevents the parasite from feeding. Our data show that the proximate cause of delayed death is an interruption of protein prenylation and consequent cellular trafficking defects.


Assuntos
Apicoplastos/metabolismo , Espaço Intracelular/metabolismo , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Animais , Antimaláricos/farmacologia , Morte Celular/efeitos dos fármacos , Hemiterpenos/metabolismo , Hemiterpenos/farmacologia , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/parasitologia , Malária Falciparum/parasitologia , Metabolômica/métodos , Compostos Organofosforados/metabolismo , Compostos Organofosforados/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/fisiologia , Prenilação de Proteína/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo , Vacúolos/parasitologia
9.
Eur J Pharmacol ; 859: 172542, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31319070

RESUMO

Nicorandil is an adenosine triphosphate-sensitive potassium channel opener with additional antioxidant properties. Doxorubicin (DOX) is an anticancer drug that exerts oxidation-mediated adverse cardiovascular effects. This study examined the effects of nicorandil on DOX-induced cytotoxicity in human umbilical vein endothelial cells (HUVECs) and underlying intracellular signaling mechanisms. Cultured HUVECs were pretreated with nicorandil (0.1, 0.3, 1, 3, and 10 µM) for 12 h and then treated with DOX (1 µM) for 24 h. Cell viability and cytotoxicity were measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays, respectively. Cell apoptosis was examined using a caspase-3 activity assay, and DNA fragmentation was detected through TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) staining. Western blot analysis was conducted to determine the related protein expression. DOX markedly increased reactive oxygen species production, p53 expression, caspase-3 activity, cleaved caspase-3 levels, and TUNEL-positive cell numbers but reduced Bcl-2 expression and intracellular antioxidant enzyme levels; these effects were effectively antagonized through nicorandil (3 µM, 12 h) pretreatment, which resulted in HUVECs being protected from DOX-induced apoptosis. Activating transcription factor 3 (ATF3), a stress-induced transcription factor, was induced by nicorandil (3 µM). Furthermore, nicorandil (3 µM) enhanced nuclear factor erythroid 2-related factor 2 (Nrf2) translocation and heme oxygenase-1 (HO-1) expression. ATF3 short interfering RNA significantly attenuated nicorandil-mediated Nrf2 translocation, HO-1 expression, and inhibitory effects on DOX-stimulated reactive oxygen species production and cell apoptosis. In summary, nicorandil may protect HUVECs from DOX-induced apoptosis, in part through ATF3-mediated Nrf2/HO-1 signaling pathways, which potentially protect the vessels from severe DOX toxicity.


Assuntos
Apoptose/efeitos dos fármacos , Doxorrubicina/efeitos adversos , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Nicorandil/farmacologia , Fator 3 Ativador da Transcrição/metabolismo , Antioxidantes/metabolismo , Citoproteção/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
10.
Nat Commun ; 10(1): 3241, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324777

RESUMO

Pharmacological strategies that boost intracellular NAD+ are highly coveted for their therapeutic potential. One approach is activation of nicotinamide phosphoribosyltransferase (NAMPT) to increase production of nicotinamide mononucleotide (NMN), the predominant NAD+ precursor in mammalian cells. A high-throughput screen for NAMPT activators and hit-to-lead campaign yielded SBI-797812, a compound that is structurally similar to active-site directed NAMPT inhibitors and blocks binding of these inhibitors to NAMPT. SBI-797812 shifts the NAMPT reaction equilibrium towards NMN formation, increases NAMPT affinity for ATP, stabilizes phosphorylated NAMPT at His247, promotes consumption of the pyrophosphate by-product, and blunts feedback inhibition by NAD+. These effects of SBI-797812 turn NAMPT into a "super catalyst" that more efficiently generates NMN. Treatment of cultured cells with SBI-797812 increases intracellular NMN and NAD+. Dosing of mice with SBI-797812 elevates liver NAD+. Small molecule NAMPT activators such as SBI-797812 are a pioneering approach to raise intracellular NAD+ and realize its associated salutary effects.


Assuntos
Ativadores de Enzimas/farmacologia , NAD/metabolismo , Mononucleotídeo de Nicotinamida/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Células A549 , Animais , Biocatálise/efeitos dos fármacos , Ativadores de Enzimas/administração & dosagem , Ativadores de Enzimas/química , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Estrutura Molecular , Fosforilação/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/química
11.
Int J Biol Macromol ; 138: 29-36, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31302123

RESUMO

In this study, we employed multiple spectroscopic methods to analyze the effects of carbon nanoparticles (CNPs) on structure of cytochrome c (Cyt c) and mitochondrial function in plant cells. The tertiary structures of aromatic amino acid in Cyt c were not changed after addition of CNPs. Cyt c was found to be absorbed on the surfaces of CNPs in a non-linear manner and only bound Cyt c can be reduced. In addition, the binding of Cyt c was found to increase the diameter of CNPs at lower concentrations. The redox potential of Cyt c was almost not affected after treatment with CNPs. There were no obvious differences in cellular ATP after exposure to CNPs, and the mitochondrial membrane potential (MMP) was significantly decreased once the CNPs concentration exceeded 31.25 µg/mL. The levels of reactive oxygen species (ROS) also were increased in BY-2 cells. Taken together, these findings provide basis for the interactions between CNPs and Cyt c, as well as the effect of CNPs treatment on the mitochondria function in plant cells.


Assuntos
Carbono/química , Carbono/farmacologia , Citocromos c/química , Citocromos c/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nanopartículas , Trifosfato de Adenosina/metabolismo , Carbono/metabolismo , Linhagem Celular , Eletroquímica , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Análise Espectral
12.
Eur J Pharmacol ; 858: 172514, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31265841

RESUMO

Recently, we reported the role of coixol (6-methoxy-2(3H)-benzoxazolone), an alkaloid from Scoparia dulcis, in glucose-dependent insulin secretion; however, its insulin secretory mechanism(s) remained unknown. Here, we explored the insulinotropic mechanism(s) of coixol in vitro and in vivo. Mice islets were batch incubated, perifused with coixol in the presence of agonists/antagonists, and insulin secretion was measured by ELISA. Intracellular cAMP levels were measured using enzyme immunoassay. K+- and Ca2+-currents were recorded in MIN6 cells using whole-cell patch-clamp technique. The in vivo glucose tolerance and the insulinogenic index were evaluated in diabetic rats treated with coixol at 25 and 50 mg/kg, respectively. Coixol, unlike sulfonylurea, enhanced insulin secretion in batch incubated and perifused islets at high glucose, with no effect at basal glucose concentrations. Coixol showed no pronounced effect on the inward rectifying K+- and Ca2+-currents in whole-cell patch recordings. Moreover, coixol-induced insulin secretion was further amplified in the depolarized islets. Coixol showed an additive effect with forskolin (10 µM)-induced cAMP level, and in insulin secretion; however, no additive effect was observed with isobutylmethylxanthine (IBMX, 100 µM)-induced cAMP level, nor in insulin secretion. The PKA inhibitor H-89 (50 µM), and Epac2 inhibitor MAY0132 (50 µM) significantly inhibited the coixol-induced insulin secretion (P < 0.01). Furthermore, insulin secretory kinetics revealed that coixol potentiates insulin secretion in both early and late phases of insulin secretion. In diabetic animals, coixol showed significant improvement in glucose tolerance and on fasting blood glucose levels. These data suggest that coixol amplifies glucose-stimulated insulin secretion by cAMP-mediated signaling pathways.


Assuntos
Benzoxazóis/farmacologia , AMP Cíclico/metabolismo , Glucose/farmacologia , Secreção de Insulina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Glicemia/metabolismo , Canais de Cálcio/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Potássio/metabolismo , Ratos
13.
Eur J Pharmacol ; 858: 172447, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31228454

RESUMO

Mirabegron is the first ß3-adrenoceptor agonist approved on the market and may offer beneficial pharmacological action in patients with overactive bladder and erectile dysfunction. Here, we further investigate the mechanisms by which mirabegron induces rat corpus cavernosum (CC) relaxation. Adult male Wistar rats were used. The CC were isolated for in vitro functional assays and ß-adrenoceptors subtypes mRNA expression evaluation. Animals were treated orally with mirabegron (30 mg/kg, 3 h), tadalafil (10 mg/kg, 3 h) or both for intracavernous pressure (ICP). Intracellular levels of cAMP and cGMP were also determined. The ß1-, ß2- and ß3-adrenoceptors subtypes were expressed in rat CC. Mirabegron produced concentration-dependent CC relaxations that were unaffected by the ß1-, ß2- or ß3-adrenoceptor antagonists atenolol (1 µM), ICI-118,551 (1 µM) and L748,337 (10 µM), respectively. Mirabegron-induced relaxations were not affected by the phosphodiesterase type 4 inhibitor, rolipram, or the adenylyl cyclase selective inhibitor, SQ 22,536. Potassium channel- or calcium influx-blockade are not involved in mirabegron-induced relaxations. In contrast, mirabegron produced rightward shifts in the contractile response induced by the α1-adrenoceptor agonist, phenylephrine. Finally, cavernous nerve stimulation caused frequency-dependent ICP increases, which were significantly increased in rats treated with mirabegron in a similar degree of tadalafil-treated rat, without promoting a significant cAMP or cGMP accumulation. Together, our results demonstrate that mirabegron induced CC relaxation through α1-adrenoceptor blockade. Care should be taken to translate the effect of mirabegron into the clinic, especially when using rat as an animal model of erectile dysfunction.


Assuntos
Acetanilidas/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Ereção Peniana/efeitos dos fármacos , Pênis/efeitos dos fármacos , Pênis/fisiologia , Tiazóis/farmacologia , Animais , Pressão Arterial/efeitos dos fármacos , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Masculino , Contração Muscular/efeitos dos fármacos , Pênis/citologia , Pênis/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores Adrenérgicos beta/genética
14.
Eur J Pharmacol ; 859: 172488, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31233746

RESUMO

Cardiac arrhythmias are among the most important pathologies that lead to sudden death. The discovery of new therapeutic options against arrhythmias with low adverse effects is of paramount importance. Farnesol is found in essential oils with antioxidant, anti-inflammatory and cardioprotective properties. The aim of this work was to investigate the effects of farnesol on the contractile and electrophysiological properties in rat heart and evaluate its antiarrhythmic action. It was evaluated farnesol effects on the left ventricular developed pressure, ECG, potassium (Ik) and L-type Ca2+ currents (ICa,L), action potential, intracellular Ca2+ transient, Ca2+ sparks and waves and reactive oxygen species production. Antiarrhythmic activity of farnesol was determined in vivo and ex vivo. The results showed that 50 µM farnesol did not alter left ventricular developed pressure, heart rate, ECG parameters and intracellular Ca2+ transient but reduced ICa,L. Farnesol reduced action potential duration at 90% repolarization. Notably, farnesol improved arrhythmia score and the incidence of the most severe arrhythmias. Farnesol attenuated the generation of reactive oxygen species, Ca2+ sparks and waves in isolated cardiomyocytes submitted to Ca2+ overload. In conclusion, farnesol has antiarrhythmic effect mediated by reducing of ICa,L and IK along with a decrease of reactive oxygen species production and normalized Ca2+ sparks and waves.


Assuntos
Antiarrítmicos/farmacologia , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Cálcio/metabolismo , Farneseno Álcool/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/patologia , Arritmias Cardíacas/fisiopatologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Canais de Cálcio Tipo L/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Eletrocardiografia/efeitos dos fármacos , Farneseno Álcool/uso terapêutico , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Masculino , Contração Miocárdica/efeitos dos fármacos , Oxigênio/metabolismo , Potássio/metabolismo , Ratos , Ratos Wistar , Disfunção Ventricular Esquerda/tratamento farmacológico
15.
Biomater Sci ; 7(8): 3287-3296, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31187805

RESUMO

Two novel porphyrin-core systems were prepared by Sonogashira cross-coupling of the terminal alkyne groups of meso-tetra(4-ethynylphenyl)porphyrin-Zn(ii) (P-1) with halogenated Ru(ii)- or Ir(iii)-phenanthroline complexes. The resulting compounds (P-Ru and P-Ir) were spectroscopically characterised and their photophysical properties were investigated (λem 625, 665 nm; τT 339.6 µs (P-Ru) and λem 530, 612, 664 nm; τT 396.6 µs (P-Ir)). Nanosecond time-resolved transient absorption studies were used to explore the 3MLCT nature of the triplet excited states, and the singlet oxygen quantum yields were determined (ΦΔ 44.8 (P-Ru), 33.2 (P-Ir)%). The subcellular uptake of P-Ru and P-Ir and their application as photosensitisers (PS) in photodynamic therapy (PDT) were explored due to their solution photophysics and absence of dark toxicity. Upon irradiation (λexc = 620-630 nm; 10 min; 33 J cm-2), both P-Ru and P-Ir killed 90% of SKBR-3 cells at 1 µM. Notably P-Ru induced a 77% decrease in cell viability at only 0.25 µM.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Irídio/química , Fotoquimioterapia/métodos , Porfirinas/química , Rutênio/química , Transporte Biológico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Complexos de Coordenação/metabolismo , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Oxigênio Singlete/metabolismo
16.
Int J Biol Macromol ; 136: 143-153, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31199976

RESUMO

The gliomas treatment is challenging due to the limits imposed by blood-brain barrier to the distribution of the drugs in the brain. Therefore, we designed a brain glioma targeting redox-sensitive hyaluronic acid (HA)-ss-curcumin (CUR) micelles. HA was conjugated to CUR through a disulfide bond, which could form micelles independently in aqueous solution. And we further increased the drug loading by loading free CUR. Brain penetration was achieved with Tween 80, whereas glioma-targeting was inclined by CD44-mediated endocytosis. Compared to the disulfide-free group, the redox-sensitive micelles exhibited rapid in vitro drug release under high glutathione conditions, significantly enhanced cell apoptosis and cellular uptake in G422 glioma cells. Redox-sensitive micelles displayed about 4.70-fold higher area under the curve in rats after intravenous injection in comparison to the free CUR and effectively accumulated in the brain. These findings suggest that redox-sensitive micelles could be a promising candidate to achieve brain targeted CUR delivery.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Curcumina/química , Glioma/tratamento farmacológico , Ácido Hialurônico/química , Ácido Hialurônico/metabolismo , Micelas , Animais , Transporte Biológico , Linhagem Celular Tumoral , Curcumina/farmacologia , Curcumina/uso terapêutico , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/farmacocinética , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Camundongos , Oxirredução , Distribuição Tecidual
17.
Biomolecules ; 9(6)2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151226

RESUMO

BACKGROUND: Dietary intake of natural antioxidants is thought to impart protection against oxidative-associated cardiovascular diseases. Despite many in vivo studies and clinical trials, this issue has not been conclusively resolved. Resveratrol (RES) is one of the most extensively studied dietary polyphenolic antioxidants. Paradoxically, we have previously demonstrated that high RES concentrations exert a pro-oxidant effect eventually elevating ROS levels leading to cell death. Here, we further elucidate the molecular determinants underpinning RES-induced oxidative cell death. METHODS: Using human umbilical vein endothelial cells (HUVECs), the effect of increasing concentrations of RES on DNA synthesis and apoptosis was studied. In addition, mRNA and protein levels of cell survival or apoptosis genes, as well as protein kinase C (PKC) activity were determined. RESULTS: While high concentrations of RES reduce PKC activity, inhibit DNA synthesis and induce apoptosis, low RES concentrations elicit an opposite effect. This biphasic concentration-dependent effect (BCDE) of RES on PKC activity is mirrored at the molecular level. Indeed, high RES concentrations upregulate the proapoptotic Bax, while downregulating the antiapoptotic Bcl-2, at both mRNA and protein levels. Similarly, high RES concentrations downregulate the cell cycle progression genes, c-myc, ornithine decarboxylase (ODC) and cyclin D1 protein levels, while low RES concentrations display an increasing trend. The BCDE of RES on PKC activity is abrogated by the ROS scavenger Tempol, indicating that this enzyme acts downstream of the RES-elicited ROS signaling. The RES-induced BCDE on HUVEC cell cycle machinery was also blunted by the flavin inhibitor diphenyleneiodonium (DPI), implicating flavin oxidase-generated ROS as the mechanistic link in the cellular response to different RES concentrations. Finally, PKC inhibition abrogates the BCDE elicited by RES on both cell cycle progression and pro-apoptotic gene expression in HUVECs, mechanistically implicating PKC in the cellular response to different RES concentrations. CONCLUSIONS: Our results provide new molecular insight into the impact of RES on endothelial function/dysfunction, further confirming that obtaining an optimal benefit of RES is concentration-dependent. Importantly, the BCDE of RES could explain why other studies failed to establish the cardio-protective effects mediated by natural antioxidants, thus providing a guide for future investigation looking at cardio-protection by natural antioxidants.


Assuntos
Dinitrocresóis/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Oxirredutases/metabolismo , Proteína Quinase C/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Resveratrol/farmacologia , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Oxirredução/efeitos dos fármacos
18.
BMC Complement Altern Med ; 19(1): 108, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117999

RESUMO

BACKGROUND: Tuberculosis is a deadly disease caused by Mycobacterium species. The use of medicinal plants is an ancient global practice for the treatment and prevention of diverse ailments including tuberculosis. The aim of this study was to isolate and characterize antimycobacterial compounds by bioassay-guided fractionation of the acetone leaf extract of Oxyanthus speciosus. METHODS: A two-fold serial microdilution method was used to determine the minimum inhibitory concentration (MIC) against mycobacteria. Cytotoxicity and nitric oxide inhibitory activity of the isolated compounds was determined to evaluate in vitro safety and potential anti-inflammatory activity. Intracellular efficacy of the crude extract against Mycobacterium-infected macrophages was also determined. RESULTS: Two compounds were isolated and identified as lutein (1) and rotundic acid (2). These had good antimycobacterial activity against the four mycobacteria tested with MIC values ranging from 0.013 to 0.1 mg/mL. Rotundic acid had some cytotoxicity against C3A human liver cells. Lutein was not cytotoxic at the highest tested concentration (200 µg/mL) and inhibited nitric oxide production in RAW 264.7 macrophages by 94% at a concentration of 25 µg/mL. The acetone crude extract (120 µg/mL) of O. speciosus had intracellular antimycobacterial activity, reducing colony forming units by more than 90%, displaying bactericidal efficacy in a dose and time-dependent manner. CONCLUSION: This study provides good proof of the presence of synergism between different compounds in extracts and fractions. It is also the first report of the antimycobacterial activity of lutein and rotundic acid isolated from Oxyanthus speciosus. The promising activity of the crude extract of O. speciosus both in vitro and intracellularly in an in vitro macrophage model suggests its potential for development as an anti- tuberculosis (TB) herbal medicine.


Assuntos
Antituberculosos , Espaço Intracelular , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais , Rubiaceae/química , Animais , Antituberculosos/química , Antituberculosos/farmacologia , Linhagem Celular , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/microbiologia , Luteína/química , Luteína/farmacologia , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7 , Triterpenos/química , Triterpenos/farmacologia
19.
Appl Biochem Biotechnol ; 189(3): 729-744, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31111375

RESUMO

Vina-ginsenoside R7 (R7) has been exhibited to engage in multiple pharmacological activities, such as antioxidant and anti-inflammatory activities. However, no photoaging-related studies have been performed on R7. Research is being conducted with the aim of assessing whether treatment with R7 has a protective effect on UVB-induced photoaging skin. Our results show that UVB exposure directly reduces matrix metalloproteinase (MMP) secretion through R7 by restraining the AP-1/MAPK pathway and blocks extracellular matrix (ECM) expression degradation. In addition, R7 improves the expression of transforming growth factor beta 1 (TGF-ß1), and type I procollagen also facilitates the synthesis of collagen by the TGF-ß/Smad signal transduction pathway. Finally, R7 valid blocks nuclear factor-κB (NF-κB) activation and enhances antioxidative stress capacity through activated nuclear factor (erythroid derived 2)-like 2 (Nrf2). In particular, the application of R7 restrains pro-inflammatory cytokines (TNF-α, IL-6, iNOS), which trigger ECM, degrade enzyme production, and suppress vascular endothelial growth factor (VEGF) secretion. In conclusion, R7 may constitute a promising cosmetic ingredient that can protect against skin photodamage resulting from detrimental UVB irradiation.


Assuntos
Anti-Inflamatórios/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Ginsenosídeos/farmacologia , Proteínas Luminescentes/farmacologia , Pele/citologia , Raios Ultravioleta/efeitos adversos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Colágeno Tipo I/metabolismo , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/efeitos da radiação , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Humanos , Interleucina-6/metabolismo , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Proteólise/efeitos dos fármacos , Proteólise/efeitos da radiação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese
20.
Int J Biol Macromol ; 134: 344-353, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31075333

RESUMO

High glucose can lead to toxicity on islet ß cells. The protective effects of a novel Lentinus edodes mycelia polysaccharide (LMP) on INS-1 cells damaged by glucose were investigated. Cell viability, lactate dehydrogenase (LDH) release, cell apoptosis, intracellular reactive oxygen species (ROS), superoxide dismutase (SOD) activity, and malondialdehyde (MDA) content were detected. P38 MAPK, JNKand NF-κB pathways were analyzed to reveal the inhibitory mechanism of LMP on glucose-induced INS-1 cells toxicity. The results showed that LMP could decrease cellular oxidative stress, reduce intracellular ROS levels, decrease MDA content and increase SOD activity. Furthermore, the glucose-induced cell apoptosis in cells were inhibited by regulating the expression of Bax, Bcl-2, cleaved caspase­3 and cleaved caspase­1. Cell signaling pathway analysis revealed that LMP could inhibit the activation of p38 MAPK, JNK, NF-κB pathways and activate Nrf2 pathway. To further explore the possible transportation mechanism of LMP with human serum albumin (HSA), ultraviolet-visible absorption spectroscopy and fluorescence spectroscopy were used to evaluate the interaction between LMP and HSA. The results showed that LMP-HSA complex was formed, which would be helpful for explaining the transportation mechanism in vivo. These results suggested that LMP might be a new therapeutic candidate to alleviate the high glucose toxicity.


Assuntos
Glucose/farmacologia , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Albumina Sérica Humana/metabolismo , Cogumelos Shiitake/química , Apoptose/efeitos dos fármacos , Transporte Biológico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , L-Lactato Desidrogenase/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Malondialdeído/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Conformação Proteica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Albumina Sérica Humana/química , Superóxido Dismutase/metabolismo
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