RESUMEN
Chlordane is a worldwide banned organochlorine insecticide because of its hazard to animal and human health. It is also a persistent organic pollutant, which can affect either the soil or the aquatic life. The same applies to other chlorinated cyclodiene insecticides, such as dieldrin and aldrin. In turn, organofluorine compounds have a widespread use in agriculture. Therefore, density functional calculations and docking studies showed that the bioisosteric replacement of chlorines in the above-mentioned compounds by fluorines improves some physicochemical parameters used to estimate the toxicity and environmental risk of these compounds, as well as the ligand-enzyme (GABAA receptor-chloride channel complex) interactions related to their insecticidal activity. This work is an effort to provide an improved new class of organofluorine pesticides.
Asunto(s)
Hidrocarburos Clorados/química , Hidrocarburos Fluorados/química , Modelos Teóricos , Plaguicidas/química , Receptores de GABA-A/química , Animales , Fenómenos Químicos , Halogenación , Humanos , Hidrocarburos Clorados/farmacología , Hidrocarburos Clorados/toxicidad , Hidrocarburos Fluorados/farmacología , Hidrocarburos Fluorados/toxicidad , Simulación del Acoplamiento Molecular , Plaguicidas/farmacología , Plaguicidas/toxicidadRESUMEN
Malaria represents a significant health issue, and novel effective drugs are needed to address parasite resistance that has emerged to the current drug arsenal. The most popular antimalarial drugs are focused on the 7-chloro-4-aminoquinoline [e.g., chloroquine (CQ), amodiaquine (AQ), isoquine (IQ), and tebuquine (TBQ)], artemisinin, and atovaquone systems. Recently, endochin has been used as a platform to design a variety of novel potent and safe antimalarial agents named endochin-like quinolones (ELQs). Also, antimalarial quinolones have been constructed from other quinolones drugs such as ICI-56780 and floxacrine. Trifluoromethyl substitution has provided a significant increase in the antimalarial response of many of the designed ELQs against Plasmodium-resistant strains and for in vivo models. In particular, attachment of a substituted trifluoromethoxy (or trifluoromethyl in some cases) biaryl side chain at 2-, 3-, 4-, or 6-position of the quinolone core has shown to be crucially important to generate selective and potent novel ELQs. Furthermore, 6-chloro and 7-methoxy moieties on the quinolone core have been identified as essential pharmacophores when the trifluoromethoxy biaryl side chain is placed at 2- or 3-position of the quinolone core. Methyl or ethyl ester attached at 3-position is essential when the trifluoromethoxy aryl side chain is attached at 6- or 7-position of the quinolone core. Some promising ELQs are currently under clinical trials, representing an excellent platform for the design of new potent, selective, effective, and safe antimalarial drugs against emergent resistance malarial models.
Asunto(s)
Antimaláricos/síntesis química , Diseño de Fármacos , Hidrocarburos Fluorados/química , Quinolonas/síntesis química , Antimaláricos/química , Antimaláricos/farmacología , Hidrocarburos Fluorados/farmacología , Malaria Falciparum/tratamiento farmacológico , Pruebas de Sensibilidad Parasitaria , Plasmodium falciparum/efectos de los fármacos , Quinolonas/química , Quinolonas/farmacologíaRESUMEN
Liver X receptors (LXR) are important transcription factors involved in the regulation of carbohydrate and lipid metabolism. Recently, we described LXR receptors expression in the hypothalamus but their function in this brain area remains unknown. Here, we evaluated the function of LXR on the expression of factors produced in the hypothalamus in vitro and in vivo by Western blotting and immunocytochemistry. More precisely we studied the expression of GnRH and GHRH, αMSH and NPY in male Sprague-Dawley rats. The effects of two synthetic LXR agonists, T0901317 and GW3965, were first tested in vitro. Hypothalamic explants were treated with either T0901317 or GW3965 (10µM) for 2, 4, 6 and 8h. As a positive control the cholesterol ABCA1 and glucose GLUT2 transporters were used. No changes were observed in the expression of the factors evaluated in vitro. The effects of the LXR agonists were then tested in vivo. Rats were injected ICV into the third ventricle with either T0901317 or GW3965 (2.5µg/5µL ICV) and after 3.5h or 24h the hypothalami were dissected out and rapidly frozen for analysis. αMSH and GnRH expression was significantly increased after 3.5h of T0901317 treatment. Anterior/posterior hypothalamic ratio increases for αMSH expression and decreases for GnRH expression after 24h of LXR activation. Altogether these results show that LXR activation affects the expression of GnRH and αMSH, suggesting that LXR in the hypothalamus is capable of modulating hypothalamic responses related to appetite, sexual behavior and reproductive functions.
Asunto(s)
Hormona Liberadora de Gonadotropina/biosíntesis , Hipotálamo/metabolismo , Receptores X del Hígado/metabolismo , alfa-MSH/biosíntesis , Animales , Expresión Génica , Hormona Liberadora de Gonadotropina/genética , Hidrocarburos Fluorados/farmacología , Hipotálamo/efectos de los fármacos , Receptores X del Hígado/agonistas , Masculino , Ratas , Ratas Sprague-Dawley , Sulfonamidas/farmacología , alfa-MSH/genéticaRESUMEN
OBJECTIVES: Activators of soluble guanylyl cyclase (sGC) act preferentially in conditions of enzyme oxidation or haem group removal. This study was designed to investigate the effects of the sGC activator BAY 60-2770 in murine airways inflammation and human eosinophil chemotaxis. METHODS: C57Bl/6 mice treated or not with BAY 60-2770 (1 mg/kg/day, 14 days) were intranasally challenged with ovalbumin (OVA). At 48 h, bronchoalveolar lavage fluid (BALF) was performed, and circulating blood, bone marrow and lungs were obtained. Human eosinophils purified from peripheral blood were used to evaluate the cell chemotaxis. RESULTS: OVA-challenge promoted marked increases in eosinophil number in BAL, lung tissue, circulating blood and bone marrow, all of which were significantly reduced by BAY 60-2770. The IL-4 and IL-5 levels in BALF were significantly reduced by BAY 60-2770. Increased protein expression of iNOS, along with decreases of expression of sGC (α1 and ß1 subunits) and cGMP levels were detected in lung tissue of OVA-challenged mice. BAY 60-2770 fully restored to baseline the iNOS and sGC subunit expressions, and cGMP levels. In human isolated eosinophils, BAY 60-2770 (1-5 µM) had no effects on the cGMP levels and eotaxin-induced chemotaxis; however, prior incubation with ODQ (10 µM) markedly elevated the BAY 60-2770-induced cyclic GMP production, further inhibiting the eosinophil chemotaxis. CONCLUSIONS: BAY 60-2770 reduces airway eosinophilic inflammation and rescue the sGC levels. In human eosinophils under oxidized conditions, BAY 60-2770 elevates the cGMP levels causing cell chemotaxis inhibition. BAY 60-2770 may reveal a novel therapeutic target for asthma treatment.
Asunto(s)
Benzoatos/farmacología , Compuestos de Bifenilo/farmacología , Eosinófilos/efectos de los fármacos , Hidrocarburos Fluorados/farmacología , Inflamación/tratamiento farmacológico , Guanilil Ciclasa Soluble/efectos de los fármacos , Animales , Antiasmáticos/farmacología , Asma/tratamiento farmacológico , Asma/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Quimiotaxis/efectos de los fármacos , GMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Eosinófilos/metabolismo , Humanos , Inflamación/inmunología , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ovalbúmina/inmunología , Guanilil Ciclasa Soluble/metabolismoRESUMEN
OBJECTIVE: To evaluate the inhibitory effect of soluble guanylate cyclase (sGC) stimulator, BAY 41-2272 (5-cyclopropyl-2-[1-(2-fluorobenzyl)- 1H-pyrazolo[3,4-b]pyridine-3-yl]pyrimidin-4-ylamine) or activator, BAY 60-2770 (4-({(4- carboxybutyl) [2- (5-fluoro-2-{[40-(trifluoromethyl) biphenyl- 4-yl]methoxy}phenyl)ethyl] amino}methyl)benzoic acid), in human and rabbit prostate smooth muscle contractility. MATERIALS AND METHODS: In rabbit or human prostate, contractions induced by electrical field stimulation or phenylephrine (PE) were carried out in the presence of sGC stimulator, BAY 41-2272, or sGC activator, BAY 60-2770. The potency (pEC50) and maximal response (Emax) values were determined. Immunohistochemistry analysis for sGC α1-subunit and quantification of intracellular levels of cyclic guanosine monophosphate (cGMP) were also performed. RESULTS: In rabbit prostate, BAY 60-2770 (30 and 300 nM) inhibited the contractions induced by PE and electrical field stimulation. The coincubation with sGC inhibitor, ODQ, produced greater inhibitions on PE-induced contractions in comparison with BAY 60-2770 alone, mainly due to greater cGMP accumulation (70- and 5.7-fold, respectively). BAY 41-2272 (300 nM) increased and decreased, respectively, cGMP levels and PE-induced contractions, but in the presence of ODQ these effects were reversed. In human prostate, immunohistochemistry analysis revealed the presence of sGC α1-subunit on the transition zone. BAY 60-2770 (300 nM) reduced significantly Emax induced by PE in human prostate. CONCLUSION: sGC activator seems to be a promising alternative to treat benign prostatic hyperplasia because it increases cGMP levels even when sGC is oxidized.
Asunto(s)
Benzoatos/farmacología , Compuestos de Bifenilo/farmacología , Hidrocarburos Fluorados/farmacología , Contracción Muscular/efectos de los fármacos , Próstata/efectos de los fármacos , Próstata/fisiología , Pirazoles/farmacología , Piridinas/farmacología , Animales , Humanos , Masculino , ConejosRESUMEN
Although the anticonvulsant activity of 3-hydroxy-3-ethyl-3-phenylproionamide (HEPP) is well-known, its use is limited by the pharmacotoxicological profile. We herein tested its fluorinated and chlorinated derivatives (F-HEPP and Cl-HEPP) with two seizure models, maximal electroshock seizures (MES), and intraperitoneal pentylenetetrazole (PTZ) administration. Neurotoxicity was examined via the rotarod test. With in silico methods, binding was probed on possible protein targets-GABAA receptors and the sodium channel Nav1.2. The median effective doses (ED50) of HEPP, F-HEPP, and Cl-HEPP in the MES seizure model were 129.6, 87.1, and 62.0 mg/kg, respectively, and 66.4, 43.5, and in the PTZ seizure model 43.5 mg/kg. The HEPP-induced neurotoxic effect, which occurred at twice the ED50 against MES (p < 0.05), did not occur with F-HEPP or Cl-HEPP. Docking studies revealed that all tested ligands bound to GABAA receptors on a site near to the benzodiazepine binding site. However, on the sodium channel open pore Nav1.2, R-HEPP had interactions similar to those reported for phenytoin, while its enantiomer and the ligands F-HEPP and Cl-HEPP reached a site that could disrupt the passage of sodium. Our results show that, as anticonvulsant agents, parahalogen substituted compounds have an advantageous pharmacotoxicological profile compared to their precursor.
Asunto(s)
Anticonvulsivantes , Hidrocarburos Clorados , Hidrocarburos Fluorados , Fenilpropionatos , Convulsiones/tratamiento farmacológico , Animales , Anticonvulsivantes/efectos adversos , Anticonvulsivantes/química , Anticonvulsivantes/farmacología , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Electrochoque , Hidrocarburos Clorados/efectos adversos , Hidrocarburos Clorados/farmacología , Hidrocarburos Fluorados/efectos adversos , Hidrocarburos Fluorados/química , Hidrocarburos Fluorados/farmacología , Masculino , Ratones , Simulación del Acoplamiento Molecular , Canal de Sodio Activado por Voltaje NAV1.2/metabolismo , Fenilpropionatos/efectos adversos , Fenilpropionatos/química , Fenilpropionatos/farmacología , Receptores de GABA-A/química , Receptores de GABA-A/metabolismo , Convulsiones/metabolismoRESUMEN
OBJECTIVES: Many natural antioxidants have poor pharmacokinetic properties that impair their therapeutic use. For hydroxycinnamic acids (HCAs) and other phenolic antioxidants, their major drawback is their low lipophilicity and a rapid metabolism. The difluoromethyl group may be considered as a 'lipophilic hydroxyl' due to its hydrogen bond donor and acceptor properties; this prompted us to assess it as a bioisosteric replacement of a phenolic hydroxyl for increasing the lipophilicity of HCAs. METHODS: Six difluoromethyl-substituted methyl cinnamates (4a-c, 5a-c) related to caffeic acid were synthesized and their antioxidant activity evaluated by chemical (FRAP, DPPH scavenging, inhibition of ß-carotene bleaching, at 1-200 µm), electrochemical (differential pulse voltammetry, cyclic voltammetry) and cell-based (inhibition of lipid peroxidation in erythrocytes, at 1 and 50 µm) assays. KEY FNDINGS: Analogues 4a-c and 5a-c were inactive in FRAP and DPPH assays and only those containing a free phenolic hydroxyl (4a and 5a) exhibited electrochemical activity although with high redox potentials. Compounds 4a,b and 5a,b were active in the inhibition of ß-carotene bleaching assay and all analogues inhibited lipid peroxidation in the human erythrocytes assay. CONCLUSIONS: Lipophilic difluoromethyl-substituted cinnamic esters retain radical scavenging capabilities that prove useful to confer antioxidant properties in a non-polar environment.
Asunto(s)
Antioxidantes/síntesis química , Antioxidantes/farmacología , Ácidos Cumáricos/síntesis química , Ácidos Cumáricos/farmacología , Hidrocarburos Fluorados/síntesis química , Hidrocarburos Fluorados/farmacología , Antioxidantes/química , Compuestos de Bifenilo/química , Células Cultivadas , Ácidos Cumáricos/química , Electroquímica , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Ferricianuros/química , Radicales Libres/química , Humanos , Hidrocarburos Fluorados/química , Peroxidación de Lípido/efectos de los fármacos , Estructura Molecular , Oxidación-Reducción , Picratos/química , beta Caroteno/químicaRESUMEN
This study reports a facile and controllable synthetic method for the preparation of both 1,3- and 1,5-isomers of 4-(3(5)-aryl-3(5)-(trifluoromethyl)-1H-pyrazol-1-yl)benzenesulfonamides, as well as a new series of 4-(3-aryl-5-hydroxy-5-(trifluoromethyl)-4,5-dihydropyrazol-1-yl)benzenesulfonamides, from the cyclocondensation reaction of 4-aryl-1,1,1-trifluoro-4-methoxybut-3-en-2-ones or 1-aryl-4,4,4-trifluoro-butane-1,3-diones or their enolic forms with 4-hydrazinylbenzenesulfonamide. All compounds of the new series of 3-substituted 1-(4-benzenesulfonamide)-5-hydroxy-5-(trifluoromethyl)-4,5-dihydropyrazoles were tested for their effect on a pathological pain model in mice. The compounds 3a, 3b, 3c, 3e, and 3f presented anti-hyperalgesic action, while the compounds 3a, 3c, 3d, 3f, and 3g exhibited anti-edematogenic effects, without causing locomotive disorders in animals, thus making them comparable to Celecoxib in an arthritic pain model.
Asunto(s)
Hidrocarburos Fluorados/síntesis química , Hiperalgesia/tratamiento farmacológico , Sulfonamidas/síntesis química , Sulfonamidas/uso terapéutico , Animales , Celecoxib , Modelos Animales de Enfermedad , Edema/tratamiento farmacológico , Edema/patología , Hidrocarburos Fluorados/química , Hidrocarburos Fluorados/farmacología , Hiperalgesia/patología , Masculino , Ratones , Estructura Molecular , Actividad Motora/efectos de los fármacos , Estereoisomerismo , Sulfonamidas/química , Sulfonamidas/farmacologíaRESUMEN
OBJECTIVE: To characterise the relaxation induced by the soluble guanylate cyclase (sGC) activator, BAY 60-2770 (4-({(4-carboxybutyl) [2- (5-fluoro-2-{[4'-(trifluoromethyl) biphenyl-4-yl]methoxy}phenyl)ethyl] amino}methyl)benzoic acid) in rabbit corpus cavernosum (CC). MATERIAL AND METHODS: The penis from male New Zealand rabbits was removed and fours strips of CC were obtained. Concentration-response curves to BAY 60-2770 were constructed in the absence and presence of inhibitors of nitric oxide synthase, N (G)-nitro-L- arginine methyl ester (L-NAME, 100 µm), sGC, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 10 µm) and phosphodiesterase type 5 (PDE-5), tadalafil (0.1 µm). The potency (pEC50 ) and maximal response (Emax ) values were determined. Then, electrical-field stimulation (EFS)-induced contraction or relaxation was tested in the absence and presence of BAY 60-2770 (0.1 or 1 µm) alone or combined with ODQ (10 µm). For EFS-induced relaxation two protocols were used: (i) ODQ (10 µm) was first incubated for 20 min and then BAY 60-2770 (1 µm) was added for another 20 min (ODQ + BAY 60-2770); (ii) in different CC strips, BAY 60-2770 was incubated for 20 min followed by another 20 min with ODQ (BAY 60-2770 + ODQ). The intracellular levels of cyclic guanosine monophosphate (cGMP) were also determined. RESULTS: BAY 60-2770 potently relaxed rabbit CC with mean (sem) pEC50 and Emax values of 7.58 (0.19) and 81 (4)%, respectively. The inhibitors ODQ (n = 7) or tadalafil (n = 7) produced 4.2- and 6.3-leftward shifts, respectively in BAY 60-2770-induced relaxation without interfering with the Emax values. The intracellular levels of cGMP were augmented after stimulation with BAY 60-2770 (1 µm) alone, whereas its co-incubation with ODQ produced even higher levels of cGMP. The EFS-induced contraction was reduced in the presence of BAY 60-2770 (1 µm) and this inhibition was even greater when BAY 60-2770 was co-incubated with ODQ. The nitrergic stimulation induced CC relaxation, which was abolished in the presence of ODQ. BAY 60-2770 alone increased the amplitude of relaxation. Co-incubation of ODQ and BAY 60-2770 did not alter the relaxation in comparison with ODQ alone. Interestingly, when BAY 60-2770 was incubated before ODQ, EFS-induced relaxation was partly restored in comparison with ODQ alone or ODQ + BAY 60-2770. CONCLUSIONS: The relaxation induced by the sGC activator, BAY 60-2770 was increased after sGC oxidation and unaltered in the absence of nitric oxide. Thus, this class of substances may have advantages over sGC stimulators or PDE-5 inhibitors for treating patients with erectile dysfunction and extensive endothelial damage.
Asunto(s)
Benzoatos/farmacología , Compuestos de Bifenilo/farmacología , Hidrocarburos Fluorados/farmacología , Relajación Muscular/efectos de los fármacos , Pene/efectos de los fármacos , Receptores Citoplasmáticos y Nucleares/agonistas , Animales , GMP Cíclico/análisis , Disfunción Eréctil , Guanilato Ciclasa , Masculino , Contracción Muscular/efectos de los fármacos , Pene/fisiología , Conejos , Guanilil Ciclasa SolubleRESUMEN
PURPOSE: Congenital diaphragmatic hernia (CDH) is associated with pulmonary hypertension which is often difficult to manage, and a significant cause of morbidity and mortality. In this study, we have used a rabbit model of CDH to evaluate the effects of BAY 60-2770 on the in vitro reactivity of left pulmonary artery. METHODS: CDH was performed in New Zealand rabbit fetuses (n = 10 per group) and compared to controls. Measurements of body, total and left lung weights (BW, TLW, LLW) were done. Pulmonary artery rings were pre-contracted with phenylephrine (10 µM), after which cumulative concentration-response curves to glyceryl trinitrate (GTN; NO donor), tadalafil (PDE5 inhibitor) and BAY 60-2770 (sGC activator) were obtained as well as the levels of NO (NO3/NO2). RESULTS: LLW, TLW and LBR were decreased in CDH (p < 0.05). In left pulmonary artery, the potency (pEC50) for GTN was markedly lower in CDH (8.25 ± 0.02 versus 9.27 ± 0.03; p < 0.01). In contrast, the potency for BAY 60-2770 was markedly greater in CDH (11.7 ± 0.03 versus 10.5 ± 0.06; p < 0.01). The NO2/NO3 levels were 62 % higher in CDH (p < 0.05). CONCLUSION: BAY 60-2770 exhibits a greater potency to relax the pulmonary artery in CDH, indicating a potential use for pulmonary hypertension in this disease.
Asunto(s)
Benzoatos/farmacología , Compuestos de Bifenilo/farmacología , Hernias Diafragmáticas Congénitas , Hidrocarburos Fluorados/farmacología , Arteria Pulmonar/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Femenino , Embarazo , ConejosRESUMEN
PURPOSE: Activators of soluble guanylyl cyclase are of potential interest as treatment for cardiovascular diseases but to our knowledge they have never been proposed to treat overactive bladder. We evaluated the effects of the soluble guanylyl cyclase activator BAY 60-2270 on voiding dysfunction and detrusor overactivity in a mouse model of obesity associated overactive bladder. MATERIALS AND METHODS: C57BL/6 male mice fed for 10 weeks with standard chow or a high fat diet were treated with 1 mg/kg BAY 60-2770 per day for 2 weeks via gavage. Cystometric evaluations were done and responses to contractile agents in isolated bladders were determined. RESULTS: Obese mice showed an irregular micturition pattern characterized by significant increases in voiding and nonvoiding contractions, which were normalized by BAY 60-2770. Carbachol, KCl and CaCl2 produced concentration dependent contractions in isolated bladder strips, which were markedly greater in obese than in lean mice. BAY 60-2770 normalized bladder contractions in the obese group. A 78% increase in reactive oxygen species generation in the bladder tissue of obese mice was observed, which was unaffected by BAY 60-2770. Treatment with BAY 60-2770 generated a tenfold increase in cyclic guanosine monophosphate in the bladders of obese mice without affecting the nucleotide level in the lean group. Protein expression of the soluble guanylyl cyclase α1 and ß1 subunits was decreased 40% in the bladder tissue of obese mice but restored by BAY 60-2770. CONCLUSIONS: Two-week BAY 60-2770 therapy increased cyclic guanosine monophosphate and rescued expression of the soluble guanylyl cyclase α1 and ß1 subunits in bladder tissue, resulting in great amelioration of bladder dysfunction.
Asunto(s)
Benzoatos/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Activadores de Enzimas/uso terapéutico , Guanilato Ciclasa/efectos de los fármacos , Hidrocarburos Fluorados/uso terapéutico , Obesidad/epidemiología , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Animales , Benzoatos/farmacología , Compuestos de Bifenilo/farmacología , Western Blotting , Hidrocarburos Fluorados/farmacología , Síntomas del Sistema Urinario Inferior/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno , Vejiga Urinaria Hiperactiva/epidemiología , Vejiga Urinaria Hiperactiva/prevención & controlRESUMEN
Cytotoxicity and subcutaneous tissue reaction of innovative blends composed by polyvinylidene fluoride and polyvinylidene fluoride-trifluoroethylene associated with natural polymers (natural rubber and native starch) forming membranes were evaluated, aiming its applications associated with bone regeneration. Cytotoxicity was evaluated in mouse fibroblasts culture cells (NIH3T3) using trypan blue staining. Tissue response was in vivo evaluated by subcutaneous implantation of materials in rats, taking into account the presence of necrosis and connective tissue capsule around implanted materials after 7, 14, 21, 28, 35, 60, and 100 days of surgery. The pattern of inflammation was evaluated by histomorphometry of the inflammatory cells. Chemical and morphological changes of implanted materials after 60 and 100 days were evaluated by Fourier transform infrared (FTIR) absorption spectroscopy and scanning electron microscopy (SEM) images. Cytotoxicity tests indicated a good tolerance of the cells to the biomaterial. The in vivo tissue response of all studied materials showed normal inflammatory pattern, characterized by a reduction of polymorphonuclear leukocytes and an increase in mononuclear leukocytes over the time (p < 0.05 Kruskal-Wallis). On day 60, microscopic analysis showed regression of the chronic inflammatory process around all materials. FTIR showed no changes in chemical composition of materials due to implantation, whereas SEM demonstrated the delivery of starch in the medium. Therefore, the results of the tests performed in vitro and in vivo show that the innovative blends can further be used as biomaterials.
Asunto(s)
Fibroblastos/metabolismo , Hidrocarburos Fluorados/farmacología , Leucocitos Mononucleares/metabolismo , Ensayo de Materiales , Polivinilos/farmacología , Almidón/farmacología , Compuestos de Vinilo/farmacología , Animales , Regeneración Ósea/efectos de los fármacos , Fibroblastos/patología , Hidrocarburos Fluorados/efectos adversos , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Leucocitos Mononucleares/patología , Masculino , Ratones , Células 3T3 NIH , Polivinilos/efectos adversos , Ratas , Ratas Wistar , Almidón/efectos adversos , Compuestos de Vinilo/efectos adversosRESUMEN
BACKGROUND AND AIMS: Nitric oxide-independent soluble guanylyl cyclase (sGC) activators reactivate the haem-oxidized enzyme in vascular diseases. This study was undertaken to investigate the anti-platelet mechanisms of the haem-independent sGC activator BAY 60-2770 in human washed platelets. The hypothesis that sGC oxidation potentiates the anti-platelet activities of BAY 60-2770 has been tested. METHODS: Human washed platelet aggregation and adhesion assays, as well as flow cytometry for α(IIb)ß(3) integrin activation and Western blot for α1 and ß1 sGC subunits were performed. Intracellular calcium levels were monitored in platelets loaded with a fluorogenic calcium-binding dye (FluoForte). RESULTS: BAY 60-2770 (0.001-10 µM) produced significant inhibition of collagen (2 µg/ml)- and thrombin (0.1 U/ml)-induced platelet aggregation that was markedly potentiated by the sGC inhibitor ODQ (10 µM). In fibrinogen-coated plates, BAY 60-2770 significantly inhibited platelet adhesion, an effect potentiated by ODQ. BAY 60-2770 increased the cGMP levels and reduced the intracellular Ca(2+) levels, both of which were potentiated by ODQ. The cell-permeable cGMP analogue 8-Br-cGMP (100 µM) inhibited platelet aggregation and Ca(2+) levels in an ODQ-insensitive manner. The cAMP levels remained unchanged by BAY 60-2770. Collagen- and thrombin-induced α(IIb)ß(3) activation was markedly inhibited by BAY 60-2770 that was further inhibited by ODQ. The effects of sodium nitroprusside (3 µM) were all prevented by ODQ. Incubation with ODQ (10 µM) significantly reduced the protein levels of α1 and ß1 sGC subunits, which were prevented by BAY 60-2770. CONCLUSION: The inhibitory effects of BAY 60-2770 on aggregation, adhesion, intracellular Ca(2+) levels and α(IIb)ß(3) activation are all potentiated in haem-oxidizing conditions. BAY 60-2770 prevents ODQ-induced decrease in sGC protein levels. BAY 60-2770 could be of therapeutic interest in cardiovascular diseases associated with thrombotic complications.