RESUMEN
A series of 1-(3-substituted-phenyl)-5-phenyl-N(3),N(4)-bis(5-sulfamoyl-1,3,4-thiadiazol-2-yl)-1H-pyrazole-3,4-dicarboxamides (4-15) were synthesized. The structures of these pyrazole-sulfonamides were confirmed by FT-IR, (1)H NMR, (13)C NMR and elemental analysis methods. Human cytosolic carbonic anhydrase (CA, EC 4.2.1.1) isozymes (hCA I and II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of newly synthesized derivatives (4-15) were investigated in vitro on esterase activities of these isozymes. The Ki values were determined as 0.119-3.999µM for hCA I and 0.084-0.878µM for hCA II. The results showed that the compound 6 for hCA I and the compound 11 for hCA II had the highest inhibitory effect. Beside that, the compound 8 had the lowest inhibition effect on both isozymes.
Asunto(s)
Anhidrasa Carbónica II/antagonistas & inhibidores , Anhidrasa Carbónica I/antagonistas & inhibidores , Inhibidores de Anhidrasa Carbónica/farmacología , Citosol/efectos de los fármacos , Pirazoles/farmacología , Sulfonamidas/farmacología , Tiadiazoles/farmacología , Anhidrasa Carbónica I/metabolismo , Anhidrasa Carbónica II/metabolismo , Inhibidores de Anhidrasa Carbónica/síntesis química , Inhibidores de Anhidrasa Carbónica/química , Citosol/enzimología , Relación Dosis-Respuesta a Droga , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/metabolismo , Estructura Molecular , Pirazoles/síntesis química , Pirazoles/química , Relación Estructura-Actividad , Sulfonamidas/química , Tiadiazoles/químicaRESUMEN
Carbonic anhydrase (CA) is a widely distributed enzyme and has a crucial role in the cells, tissues and organs of living organisms. It is found that CA-II is one of the most abundant CA isoenzymes in the gastrointestinal system. It plays an important role in the gastric acid secretion in stomach. In this study, we purified CA-II isoenzyme from sheep stomach with a 615.2 purification fold, 78% purification yield and 5562.02 specific activity. Moreover, the in vitro effects of some commonly used pesticides including chlorpyrifos, cypermethrin, dichlorvos, glyphosate isopropylamine and lambda cyhalomethrin on the enzyme activity were investigated. Of these compounds, glyphosate isopropylamine and dichlorvos showed an inhibition on CA-II esterase activity. They have IC50 values of 0.155 µM and 2.690 µM and Ki values of 0.329 µM and 3.654 µM, respectively. Both glyphosate isopropylamine and dichlorvos inhibited CA-II isoenzyme in a noncompetitive manner.
Asunto(s)
Anhidrasa Carbónica II/metabolismo , Plaguicidas/toxicidad , Estómago/efectos de los fármacos , Animales , Anhidrasa Carbónica II/antagonistas & inhibidores , Inhibidores de Anhidrasa Carbónica/toxicidad , Cloropirifos/toxicidad , Diclorvos/toxicidad , Piretrinas/toxicidad , Ovinos , Estómago/enzimologíaRESUMEN
The synthesis, characterization and biological evaluation of novel pyrazole carboxamide derivatives (2-9) are presented. (1)H and (13)C NMR have been used for the structure description, possible tautomeric structures determination and hydrogen bonding observation. FT-IR results have confirmed the synthesis of the pyrazole derivatives while thermal gravimetric analysis has confirmed thermal stability up to 300°C. The melting temperatures are strongly dependent on their crystal structure as confirmed by differential scanning calorimetry and X-ray diffraction measurements. Impacts of 2-9 as possible antiglaucoma agents were investigated on carbonic anhydrase I and II (CA-I and II) isozymes purified from human erythrocytes in vitro. Compounds 3 and 9 had the highest inhibitory effect while compounds 6 and 8 showed the lowest inhibition.
Asunto(s)
Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/metabolismo , Pirazoles/farmacología , Inhibidores de Anhidrasa Carbónica/síntesis química , Inhibidores de Anhidrasa Carbónica/química , Anhidrasas Carbónicas/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Eritrocitos/enzimología , Humanos , Estructura Molecular , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/aislamiento & purificación , Isoformas de Proteínas/metabolismo , Pirazoles/síntesis química , Pirazoles/química , Relación Estructura-ActividadRESUMEN
Harel et al. (2004) report that atherosclerosis is the underlying cause for 50% of the mortality in Western societies, and organophosphates in nature constitute an important risk as well as a terrorist threat for all living things. Since paraoxonase enzyme (PON) is a bioscavenger against both atherosclerosis and organophosphate toxicity, studies on paraoxonase enzyme (PON) occupy an important place in the scientific world. In this study, we purified PON1 enzyme from human serum by using a simple three-step purification method: ammonium sulfate precipitation, ion-exchange chromatography and gel filtration chromatography. In addition, we investigated the effects of certain cardiovascular drugs on human serum paraoxonase enzyme activity. IC(50) values and K(i) constants were calculated for digoxin, metoprolol tartrate, verapamil, diltiazem, amiodarone, dobutamine, and methylprednisolone, which show inhibitory effects. IC(50) values were determined to be 0.012 microM, 0.621 microM, 0.672 microM, 1.462 microM, 3.255 microM, 4.495 microM and 47.803 microM, respectively, and K(i) constants were calculated to be 0.035+/-0.01273 microM, 1.115+/-0.27003 microM, 1.188+/-0.11529 microM, 3.104+/-1.00478 microM, 5.427+/-1.34063 microM, 10.7+/-3.14572 microM and 109+/-17.47875 microM, respectively. A comparison of the IC(50) and K(i) values of the drugs revealed that digoxin has the maximum inhibition rate. Furthermore, methylprednisolone and amiodarone were found to be competitive inhibitors, verapamil and dobutamine were uncompetitive inhibitors, while others inhibited the enzyme in noncompetitive manner.